Large Weapons Research Articles

Research on General Design of Virtual Maintenance Training Platform for Large Equipment Based on 3D Simulation

The general design of virtual maintenance platform based on 3D simulation is given to solve the difficulty of maintenance training for large equipment. Firstly, primary functions of platform are defined by comparing common platform with application system. Secondly, component structure and interaction structure of platform are designed based on common thinking of subsystem-serverice. Finally, technology systems of platform including common simulation framework and training basing on 3D simulation are also presented to realize simulation software. It will provide beneficial reference for maintenance training simulation of other similar large weapon equipment.

Alpine ibex males grow large horns at no survival cost for most of their lifetime

Large horns or antlers require a high energy allocation to produce and carry both physiological and social reproductive costs. Following the principle of energy allocation that implies trade-offs among fitness components, growing large weapons early in life should thus reduce future growth and survival. Evidence for such costs is ambiguous, however, partly because individual heterogeneity can counterbalance trade-offs. Individuals with larger horns or antlers may be of better quality and thus have a greater capacity to survive. We investigated trade-offs between male early horn growth and future horn growth, baseline mortality, onset of actuarial senescence, and rate of ageing in an Alpine ibex (Capra ibex ibex) population. Horn growth of males in early life was positively correlated to their horn length throughout their entire life. Cohort variation and individual heterogeneity both accounted for among-individual variation in horn length, suggesting both long-lasting effects of early life conditions and individual-specific horn growth trajectories. Early horn growth did not influence annual survival until 12 years of age, indicating that males do not invest in horn growth at survival costs over most of their lifetime. However, males with fast-growing horns early in life tended to have lower survival at very old ages. Individual heterogeneity, along with the particular life-history tactic of male ibex (weak participation to the rut until an old age after which they burn out in high mating investment), are likely to explain why the expected trade-off between horn growth and survival does not show up, at least until very old ages.

Research on Virtual Reality Based Equipment Operation Training Simulation with GL Studio

Aiming at the difficulty of large weapon equipment operation training simulation, GL Studio software tool was adopted based on VR technology. A hierarchy structure was put forward to simulate all kinds of integrating equipment system, single equipment and operation unit. Key technologies including Model database structure optimization, LOD, operation unit motion simulation based on DOF and screen show simulation based on switch are also put forward in detail. Finally, a simulation example of VR based large weapon equipment operation simulation training system was presented to prove its feasibility.

A Case of a Gunshot Wound with 5.7 × 28 mm Ammunition

The 5.7 × 28 mm family of cartridges was designed by Fabrique Nationale in Belgium as a military cartridge designed to penetrate body armor while still being fired from a small personal defense weapon that could be carried by military personnel whose activities precluded carrying larger weapons. To accomplish this, the designers relied upon a projectile with a steel penetrator and extremely high velocities. As hollow point ammunition is forbidden from military use by the Hague Convention, the projectile was designed to deposit its energy within the body by yawing (tumbling) rather than expanding or deforming. Since its introduction, civilian variants of the 5.7 × 28 mm cartridge have been developed, and while the projectiles of these cartridges are not armor piercing, some appear to retain the yawing characteristics of the military projectiles as illustrated in the case of an individual shot with a civilian variant of the 5.7 × 28 mm cartridge where the yaw was evidenced by the rear-first positioning of the projectile when recovered at autopsy.

Coupled Heat Transfer Analysis of Interlayer Active Cooling Barrel of Large Caliber Gun Based on CFX

Large caliber naval gun weapon system in sustained and rapid firing process, produced high temperature and high pressure gas will form pulsed high temperature flow in barrel, causing the barrel being heated and cooled sharply and then being in bad environment, affecting the life of the barrel. The research object of this paper is based on 155mm naval gun, to utilize the theories of fluid mechanics and heat transfer and use ANSYS-CFX software, to simulate the heat response of the gun’s rifling original portion under interlayer active cooling, and to analyse the effects of structure parameters of interlayer cooling system and flowing parameters of cooling liquid on cooling performance using the principle of heat transfer enhancement, providing guidance for the optimization of the structure of the interlayer cooling system.

Soldiers with large weapons in predator-abundant midsummer: phenotypic plasticity in a eusocial aphid

Eusocial aphids produce sterile individuals (“soldiers”) that specialize behaviorally and morphologically to protect their colony from predators, while production of soldiers can negatively affect colony growth because of reproductive allocation and opportunity cost. Hence, a cost-saving soldier production strategy is expected to be favored. Here, we hypothesize that, to save the cost, a eusocial aphid Ceratovacuna japonica produces soldiers with smaller weapon in the season when predators are not abundant. The abundance of two specialist lepidopteran predators (i.e., Taraka hamada and Atkinsonia ignipicta) of C. japonica dramatically increased, and aphid colony size significantly decreased, from July to August. In line with these, the soldiers in August had larger weapons (i.e., frontal horns) than those in June, indicating a correlational increase in weapon size with predation pressure. We predict that a reliable prospective signal indicating the coming of midsummer (environmental temperature) induces mother aphids to produce soldiers with larger weapons. Experiments clarified that soldiers produced at 20 °C (typical temperature of July to August) had larger weapons than those produced at 15 °C (typical temperature of May to July). Such phenotypic plasticity appears to be adaptive to maximize the fitness of C. japonica under a temporally variable but predictable predation environment. These results indicate that C. japonica aphids not merely have distinctive reproductive—and soldier castes, but also produce differentially armed soldiers in a habitat with temporally changing predation risks.

Sperm Traits Negatively Covary with Size and Asymmetry of a Secondary Sexual Trait in a Freshwater Crayfish

In species where females mate promiscuously, the reproductive success of males depends both on their ability to acquire mates (pre-copulatory sexual selection) and ability of their ejaculates to outcompete those of other males (post-copulatory sexual selection). Sperm competition theory predicts a negative relationship between investment in body traits favouring mate acquisition (secondary sexual characters, SSCs) and investment in ejaculate size or quality, due to the inherent costs of sperm production. In contrast, the phenotype-linked fertility hypothesis posits that male fertilizing efficiency is reliably reflected by the phenotypic expression of male SSCs, allowing females to obtain direct benefits by selecting more ornamented males as copulation partners. In this study, we investigated the relationships between male SSCs and size and quality (viability and longevity) of ejaculates allocated to females in mating trials of the freshwater crayfish Austropotamobius italicus. We showed that the relative size of male weapons, the chelae, was negatively related to ejaculate size, and that chelae asymmetry, resulting from regeneration of lost chelipeds, negatively covaried with sperm longevity. Moreover, males allocated more viable sperm to mates from their own rather than different stream of origin. Our findings thus suggest that, according to sperm competition theory, pre-copulatory sexual selection for large weapons used in male fighting may counteract post-copulatory sperm competition in this crayfish species, and that investment in cheliped regeneration may impair ejaculate quality.

Study on the Implementation Method of Data Review for a Certain Weapon System in VxWorks

In the researching and using process of a certain large weapon system, the practical navigation data was the most important and effective way for the system analysis and the fault reoccurrence. Aiming at the characteristics of the weapon launching and control system such as multiple data types, complex data property, and complex data management, the embedded computer system based on VxWorks is used in this article to realize the review of multiple kinds of data by the timer interrupt mode, and through relative experiments, the result showed that the real-time review system of the large-capacity practical navigation data designed in this article was effective and reliable, completely fulfilling the design requirements.

Blogging – the Cultural Logic of Communicative Capitalism: Dean’s Blog Theory

Blogging – the Cultural Logic of Communicative Capitalism: Dean’s Blog Theory Mark Andrejevic (bio) Jodi Dean, Blog Theory: Feedback and Capture in the Circuits of Drive Polity Press: 2010. $19.95 (paper) $54.95 (cloth). 140 pages. ISBN-10: 074564970X To appreciate Jodi Dean’s diagnosis of communicative capitalism, we might revisit the Bush administration’s handling of a potentially damaging revelation about its failure to secure a large weapons cache during the 2003 invasion of Iraq. Despite the fact that the International Atomic Energy Agency had repeatedly warned the administration about the weapons at Al Qa’Qaa, calling it, “the greatest explosives bonanza in history” (Glanz, Broad, & Sanger, 2004), no US troops had been tasked with protecting it during the tumult of the initial invasion. When inspectors reached the site, its seal was broken and the explosives looted, perhaps helping to explain where the opposition was getting its seemingly bottomless supply of high-grade explosives for improvised explosive devices and other weapons. Rather than providing a clear and potentially damaging explanation of their failure – and risk embarrassment during the 2004 Presidential campaign – Bush officials created a smokescreen of often contradictory claims. Perhaps the most honest response came early on, when one official confessed to the New York Times, “It's not an excuse … but a lot of things went by the boards” (Glanz, Broad, & Sanger, 2004). Over time, as the damaging import of the revelation became clear, the administration back-tracked, suggesting at various times that the site had been looted before US troops arrived; that Iraqis had smuggled the weapons into Syria before the invasion; and alternatively that the explosives hadn’t disappeared at all, but had been accounted for and disposed of by US troops. Under pressure from reporters, administration officials alternatively claimed that the president had not known about the missing cache until a few days before the story broke and that the White House had initiated an in-depth investigation once the explosives had been reported missing several months earlier. As the days passed, the smoke screen just got thicker – with the administration capitalizing on the impossibility of getting the full story (thanks in part to its own reluctance to release definitive details) as a means of discrediting critics. Demonstrating the success of the administration’s strategy, a reporter for the US News and World Report concluded somewhat forlornly, “there are many more questions than answers regarding this story” (Lou Dobbs Tonight, 2004). Mission accomplished. The administration’s strategy deftly dismantled the promise of the information age that enhanced access to information might help hold authorities accountable and provide citizens with a clearer, shared understanding of their world. It also exemplified an increasingly familiar strategy for information control in the digital era: rather than trying to enforce a dominant narrative, this strategy relies upon multiplying competing narratives that highlight the indeterminacy of any and all accounts as well as the associated inability to adjudicate between them. The intended result is the neutralization of critique via the dilution of compelling counter-narratives and the promulgation of uncertainty. As a Bush administration spokesperson put it, in response to the Kerry campaign’s charge of negligence in the Al Qa’Qaa case: “John Kerry presumes to know something that he could not know: when the material disappeared…Since he does not know whether it was gone before the war began, he can't prove it was there to be secured” (Sanger, 2004). In a breathtaking bit of rhetorical Jiu-Jitsu, this defense turned the administration’s own incompetence (in the form of its admission that it had lost track of the weapons) into a preemptive counter-attack. In the case of Al Qa’Qaa, critique dissipated in the shifting currents of multiple competing narratives. This strategy is in keeping with an internet era of information glut, in which, “Abundant, dispersed, mashed-up messages…displace previous communication strategies focused on direct image control. Even when facts are corrected, fictions remain, repeated and circulated in affective networks” (Dean, p. 100). Faced with the welter of information, citizens are left to pick the narrative that fits best with their own preconceptions and affective investments. Dean describes the resulting impasse of representation...

Detecting buried metallic weapons in a controlled setting using a conductivity meter

Forensic personnel may face a daunting task when searching for buried weapons at crime scenes or potential disposal sites. In particular, it is common to search for a small firearm that was discarded or buried by a perpetrator. When performing forensic searches, it is recommended to first use non-invasive methods such as geophysical instruments to minimize damage to evidence and to the crime scene. Geophysical tools are used to pinpoint small areas of interest across a scene for invasive testing, rather than digging large areas throughout the site. Prior to this project, there was no published research that tested the utility of the conductivity meter to search for metallic weapons such as firearms and blunt and sharp edged weapons. A sample comprised of 32 metallic weapons including firearms, blunt and sharp edged weapons, and scrap metals was buried in a controlled setting to test the applicability of a conductivity meter for forensic searches. Weapons were tested at multiple depths and after data collection was performed for one depth, the weapons were reburied 5 cm deeper until they were no longer detected. Variables such as weapon size, burial depth, transect interval spacing (25 and 50 cm), and metallic composition were tested. All of the controlled variables influenced maximum depth of detection. For example, size was a factor as larger weapons were detected at deeper depths compared to smaller weapons. Metal composition affected maximum depth of detection as the conductivity meter detected items comprised of ferrous metals at deeper depths than non-ferrous metals. Searches for large buried items may incorporate a transect interval spacing of 50 cm but small weapons may be undetected between transects and therefore a transect interval spacing of 25 cm is recommended. Overall, the conductivity meter is a geophysical tool to consider when searching for larger-sized metallic weapons or to use in conjunction with an all-metal detector, particularly when searching for buried metallic evidence in obstructed areas.

Compensatory Growth Limits Opportunities for Artificial Selection in Alpine Chamois

ABSTRACT In ungulates, big males with large weapons typically outcompete other males over access to estrous females. In many species, rapid early growth leads to large adult mass and weapon size. We compared males in one hunted and one protected population of Alpine chamois (Rupicapra rupicapra) to examine the relationship between horn length and body mass. We assessed whether early development and hunter selectivity affected age‐specific patterns of body and horn size and whether sport hunting could be an artificial selection pressure favoring smaller horns. Adult horn length was mostly independent of body mass. For adult males, the coefficient of variation of horn length (0.06) was <50% of that for body mass (0.16), suggesting that horn length presents a lower potential for selection and may be less important for male mating success than is body mass. Surprisingly, early development did not affect adult mass because of apparent compensatory growth. We found few differences in body and horn size between hunted and protected populations, suggesting the absence of strong effects of hunting on male phenotype. If horn length has a limited role in male reproductive success, hunter selectivity for males with longer horns is unlikely to lead to an artificial selective pressure on horn size. These results imply that the potential evolutionary effects of selective hunting depend on how the characteristics selected by hunters affect individual reproductive success.

Understanding Interior Ballistic Processes in a Flash Tube

Abstract Vented flash tubes have often been used in the ignition train of medium and large caliber weapon systems. Despite their long history of ballistic usage, there are undesirable features associated with uneven venting of the combustion products. Pressure measurements at various locations from the flash tube have shown severe variations with time, which is associated with spatially nonuniform mass discharging rate from the vent holes. Measured pressure profiles in the flash tube show counterintuitive, nonmonotonic pressure distributions with the lowest pressure in the middle of the venting section of the flash tube. A model of the flash tube venting process was developed to explain these phenomena using modern, high-order numerical schemes. Source terms accounting for mass addition from the black powder pellets, mass loss through the vent holes, wall friction, differential area changes, and volume changes from surface regression of black powder pellets were fully coupled in the model. The numerical results of this model reproduced the severe pressure variations and nonmonotonic pressure profiles observed in experiments. In general, they are caused by gas dynamic effects from a slowly moving normal shock wave in the middle portion of the venting section of the flash tube. As the driving pressure from the burning black powder pellets changes, the location of the normal shock wave jumps from one vent hole set to another, producing pressure variations observed in experiments. The physical understanding gained from this model solution has provided guidance for achieving more uniform mass discharging rate by varying the vent hole sizes as a function of distance along the flash tube.

Weapon noise exposure of the soldier and its measurement.

On the battlefield a soldier is continuously exposed to various types of noise. Much of this exposure is noise generated by his own weapon or by weapons of close by troops. The exposure levels are between 160-dB peak for small arms and 190-dB peak at the soldier’s ear for some antitank weapons, with A-durations from 0.3 ms (small caliber) to 4 ms for large caliber weapons (e.g., Howitzers). As these parameters feed into the damage risk criteria which are in use by the armed forces of different countries, it is important that the recorded pressure time histories are as precise as possible. The paper will present the acoustic levels to which a soldier may be exposed by different types of weapon and under different circumstances. It also will present measurement techniques to use for reliable results.

Assessing attitudes toward military blast noise.

Existing impact assessment procedures for large weapon noise or blast noise do not fully meet the military’s noise management needs. Military noise impacts currently are assessed in terms of the response metric annoyance as predicted by a long-term average noise level metric. This method has proven to be unsatisfactory for impulsive military noise. As a result, ERDC-CERL and SERDP have launched a series of field studies to enhance the understanding of human response to military blast noise. An overview of the four research protocols employed in this project will be presented, and the most recent findings from a qualitative personal interview study and a complaint and annoyance comparison study will be given. The preliminary results indicate that residents living near military installations adapt to the basic noise environment over time, notice unusually large noise events or events that produce house vibrations, and indicate that those who file complaints are significantly more annoyed on average than their neighbors who were exposed to a similar noise environment. All findings in this project thus far indicate that the number, timing, and level of discrete blast events are important for predicting the human response to blast noise.

Homicide of six family members using multiple methods in Sri Lanka

A family of six members were murdered at their own residence. Four of the family members had been killed with large heavy sharp weapons which produced multiple deep cut injuries predominantly on the neck and face. In these victims, death occurred as a result of haemorrhage. Two family members were killed by ligature strangulation and hanging. The victim, who was hanged, was sexually abused before she was killed. An unusual finding was the presence of an alleged assailant to the murders with multiple blunt weapon trauma to his body, at the scene of crime. The homicides of the family were as a result of personal disputes between the perpetrators who were their neighbours. Three of the alleged assailants were charged for murder and rape. The fourth assailant was charged for rape. No conclusive evidence as to who caused the death of the alleged perpetrator was reached.

Influence of sociality on allometric growth and morphological differentiation in sponge-dwelling alpheid shrimp

Eusocial societies are defined by a reproductive division of labour between breeders and nonbreeders that is often accompanied by morphological differentiation. Some eusocial taxa are further characterized by a subdivision of tasks among nonbreeders, often resulting in morphological differentiation among different groups (subcastes) that specialize on different sets of tasks. We investigated the possibility of morphological castes in eusocial shrimp colonies (Zuzalpheus, formerly part of Synalpheus) by comparing growth allometry and body proportions of three eusocial shrimp species with three pair-forming species (species where reproductive females and males occur in equal sex ratios). Allometry of eusocial species differed in several respects from that of pair-forming species in both lineages. First, allometry of fighting claw size among individuals other than female breeders was steeper in eusocial than in pair-forming species. Second, breeding females in eusocial colonies had proportionally smaller weapons (fighting claws) than females in pair-forming species. Finally, claw allometry changed with increasing colony size in eusocial species; large colonies showed a diphasic allometry of fighting claw and finger size, indicating a distinctive group of large individuals possessing relatively larger weapons than other colony members. Shrimp are thus similar to other eusocial animals in the morphological differentiation between breeders and nonbreeders, and in the indication that some larger nonbreeders might contribute more to defence than others. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 527–540.

Large weapon source emission data protocols and results

The U.S. Army needs detailed information about the blast pressure field created by large weapons to avoid negative impacts on testing and training mission capabilities due to noise. The noise software tools BNOISE2™ and RMTK Noise Tool, which the Department of Defense (DoD) uses to predict and assess impacts of large weapon noise, require accurate acoustic source emission models. A free‐field representation of the sound source acoustical emission, containing no waveform signal perturbations due to the ground, other reflecting surfaces, ballistic waves, or propagation anomalies, is required. The measurement protocols have been developed to collect the free‐field source emission data. These protocols are described along with acoustical data and emission source results for the 120 mm M‐1 tank gun, the 105 mm Stryker gun, and various weights of C‐4 explosives. In addition, the measured acoustic data are compared with an idealized Friedlander curve. The overall results demonstrate that the protocols do provide...

Offertradition og religion i ældre jernalder i Sydskandinavien – med særlig henblik på bebyggelsesofringer

Offertradition og religion i ældre jernalder i Sydskandinavien – med særlig henblik på bebyggelsesofringer

Optical communications in the mid-wave IR spectral band

The mid-wave IR (MWIR) spectral band extending from 3 to 5 microns is considered to be a low loss atmospheric window. The MWIR wavelengths are eye safe and are attractive for several free-space applications including remote sensing of chemical and biological species, hard target imaging, range finding, target illumination, and free-space communications. Due to the nature of light-matter interaction characteristics, MWIR wavelength based systems can provide unique advantages over other spectral bands for these applications. The MWIR wavelengths are found to effectively penetrate natural and anthropogenic obscurants. Consequently, MWIR systems offer increased range performance at reduced power levels. Free-space, line-of-sight optical communication links for terrestrial as well as space based platforms using MWIR wavelengths can be designed to operate under low visibility conditions. Combined with high-bandwidth, eye-safe, covert and jam proof features, a MWIR wavelength based optical communication link could play a vital role in hostile environments. A free-space optical communication link basically consists of a transmitter, a receiver and a scheme for directing the beam towards a target. Coherent radiation in the MWIR spectral band can be generated using various types of lasers and nonlinear optical devices. Traditional modulation techniques are applicable to these optical sources. Novel detector and other subcomponent technologies with enhanced characteristics for a MWIR based system are advancing. Depending on the transmitter beam characteristics, atmospheric conditions may adversely influence the beam propagation and thereby increasing the bit error rate. For satisfactory transmission over a given range, the influence of atmosphere on beam propagation has to be analyzed. In this chapter, salient features of atmospheric modeling required for wavelength selection and performance prediction is presented. Potential optical sources and detectors for building a practical MWIR communication link are surveyed. As an illustration, the design configuration and experimental results of a recently demonstrated free-space, obscurant penetrating optical data communication link suitable for battlefield applications is discussed. In this case, the MWIR wavelength was derived using an all solid-state, compact, optical parametric oscillator device. With this device, weapon codes pertaining to small and large weapon platforms were transmitted over a range of 5 km. Furthermore, image transmission through light fog, accomplished using this hardware, is also presented. Advances in source and detector technologies are contributing to the development of cost effective systems compatible with various platforms requirements. In coming years, MWIR wavelengths are anticipated to play a vital role in various human endeavors.

Book Review on Fire

Book Review on Fire