The Terminal Middle Period (3000 to 2000 B.P.) and the Transitional Late Period (2000 B.P. to 1500 B.P.) contain a number of diverse projectile point styles belonging to several cultural complexes. The cultural complexes studied here include: Pelican Lake, Besant, Outlook, Bracken, Sonota and Sandy Creek. The point styles associated with these complexes have been in the past separated on largely visual or subjective bases. Clarifying the projectile point morphologies during this period will allow for better interpretations of archaeological sites on the Northern Plains. To aid in this clarification, twelve projectile point assemblages from nine previously excavated sites on the Saskatchewan and Alberta Plains were studied. These assemblages were subjected to geometric morphometric and discriminate function analysis. Beyond these two avenues of analysis, the assemblages were also subjected to metric testing to determine if the point styles were more consistent with arrow or dart projectiles. During this time period, the technological transition from the atlatl and dart to bow and arrow appears to have occurred. As a result of the arrow/dart testing, a pattern of robustness was seen in the kill site assemblages as compared to the habitation site assemblages. This resulted in larger points being found in communal kill sites in the study suggesting a link between game size and hunting methods. The result from this analysis recommends a reduction in the independent point styles suggested by other researchers. The data trends towards the finding that two major cultural complexes existed in the Terminal Middle / Transitional Late periods in the studied region of Northern Plains, Pelican Lake and Besant. A third minor group morphologicaly between the two major groups.

Airburst projectiles increase the effectiveness of air defense, by forming clouds of small pellets. In this work, in order to evaluate the effectiveness of airburst projectiles, Single Shot Kill Probability (SSKP) is computed at different burst distances by using three lethality functions defined from different measures of effectiveness. These different measures are target coverage, number of sub-projectile hits on the target and kinetic energy of sub-projectiles after burst. Computations are carried out for two different sub-projectile distribution patterns, namely circular and ring patterns. In this work, for the determination of miss distance, a Monte Carlo simulation is implemented, which uses Modified Point Mass Model (MPMM) trajectory equations. According to the results obtained two different distribution patterns are compared in terms of effectiveness and optimum burst distance of each distribution pattern is determined at different ranges.

Short range thrusting projectiles are one of the various threats against armored vehicles and helicopters on the battlefield. Developing a countermeasure for this kind of projectiles is very crucial since they are vast in number and easy to operate on the battlefield. A countermeasure may consist of fire point prediction of the projectile and attack the launcher of it, or it may be the impact point prediction of the projectile and apply a hard-kill counter measure on its way to the ally target. For both of the countermeasure concepts, dynamics and parameters of the projectile must be estimated precisely. In this thesis, dynamic models for thrusting and ballistic flight modes of thrusting projectile are obtained. Three different tracking filters are suggested for precise tracking of the projectiles and their estimation performances are compared. These filters are the Extended Kalman Filter (EKF), the Particle Filter (PF) and the Marginalized Particle Filter (MPF).

GPS is a widely accepted means of navigation, whether it is for civilian or military means. With the implementation of GPS on smart projectiles, these weapons have been able to achieve remarkable accuracy. Even though the improvements in accuracy are impressive, GPS signals are susceptible to jamming and spoofing by a sufficiently motivated enemy. The work reported here examines the viability of constructing a navigation solution using ground based signals of opportunity that provide range and range rate information. Using a generalized sensor model encompassing the key error terms, a variety of physical devices are included in the analysis. For a typical indirect fire trajectory, navigation solutions are computed as a function of the number and density of signal sources, terrain type, and sensor errors. Systematic studies were performed using these parameters in order to better understand the merits and demerits of this type of system to create a useful navigation solution. Based on these studies, results indicate that navigation solutions can be computed with the same accuracy as current GPS systems with a moderate number of signal sources. Generally, more accurate solutions are obtained when the projectile is directly over the signal sources and there is variation of signal source location in all three axes.

Currently, there are few analytical tools within the ballistics community to aid in the design and performance evaluation of aerodynamically asymmetric projectiles. The scope of this thesis is to (1) create analytical tools that are capable of quantifying aerodynamically asymmetric projectile performance, (2) demonstrate the ability of these models to accurately account for aerodynamic asymmetries, and (3) gain insight into the flight mechanics of several aerodynamically asymmetric projectiles. First, a six-degree-of-freedom (6 DOF) flight dynamic model, which uses a point-force lifting-surface aerodynamic model, was developed to replicate flight characteristics observed from measured results of common projectiles. A quasi-linear flight dynamic model was then created using the machinery of Projectile Linear Theory (PLT). From this, flight dynamic stability models were developed for linear time-invariant (LTI) and linear time-periodic (LTP) systems. Dynamic simulation and stability trade studies were then conducted on asymmetric variants of 4-finned, 3-finned, 2-finned, and hybrid projectile configurations. First, stability of symmetric projectiles are validated and show that the classical and extended PLT model yielded identical results. Results show that aerodynamic asymmetries can sometimes cause instabilities and other times cause significant increase in dynamic mode damping and increase/decrease in mode frequency. Partially asymmetric (single plane) configurations were shown to cause epicyclic instabilities as the asymmetries became severe, while fully asymmetric (two plane) can grow unstable in either the epicyclic modes or the roll/yaw mode. Another significant result showed that the LTP stability model is able to capture aerodynamic lifting-surface periodic affects to evaluate dynamic stability requirements for asymmetric projectiles.

Thesis (M.A.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 16, 2009). Includes bibliographical references (p. 63-70).

The purpose of this project is to demonstrate a technique in producing reproductions of points in acrylic. Based on an article by John R. Rohner in Volume 35 of American Antiquity entitled, "Techniques of Making Plastic Casts of Artifacts 'From Permanent Molds".The project expanded on this idea, and added different steps in order to simplify the procedure. Completed, the finished points will be used as teaching aids.

La maîtrise du comportement en vol d'un projectile est, en partie, conditionnée par la connaissance des coefficients associés à chaque effort aérodynamique. Différents outils sont utilisés dans l'industrie, tels que les codes numériques aérodynamiques ou les essais en soufflerie, afin d'obtenir une première estimation des coefficients en phase d'avant-projet. Il est ensuite nécessaire de vérifier la valeur des coefficients et de valider le comportement du projectile en vol au moyen de tirs instrumentés. Un outil automatisé est donc proposé afin d'identifier les coefficients aérodynamiques d'un projectile à partir des mesures issues d'un vol. La technique d'identification est pensée pour être applicable à une gamme la plus large de projectiles. Elle introduit un problème d'optimisation non linéaire en dimension finie. La fonctionnelle du problème contient deux termes : un terme d'écart entre les paramètres d'état et les mesures, de sorte à s'approcher au mieux des mesures et à les relaxer, et un terme de pénalisation prenant en compte les équations de la mécanique du vol. L'outil proposé est testé, pour un projectile de type flèche, avec des données simulées ou avec des données issues de tirs. Il permet l'identification des coefficients aérodynamiques recherchés. L'algorithme est robuste face au bruit et permet également la reconstruction d'une trajectoire débruitée.

Thesis (M.A.)--Florida State University, 2006. / Advisor: Rochelle A. Marrinan, Florida State University, College of Arts and Sciences, Dept. of Anthropology. Title and description from dissertation home page (viewed June 16, 2006). Document formatted into pages; contains xv, 136 pages. Includes bibliographical references.

abstract: Patterns of social conflict and cooperation among irrigation communities in southern Arizona from the Classic Hohokam through the Historic period (c. 1150 to c. 1900 CE) are analyzed. Archaeological survey of the Gila River Indian Community has yielded data that allow study of populations within the Hohokam core area (the lower Salt and middle Gila valleys). An etic design approach is adopted that analyzes tasks artifacts were intended to perform. This research is predicated on three hypotheses. It is suggested that (1) projectile point mass and performance exhibit directional change over time, and weight can therefore be used as a proxy for relative age within types, (2) stone points were designed differently for hunting and warfare, and (3) obsidian data can be employed to analyze socioeconomic interactions. This research identifies variation in the distribution of points that provides evidence for aspects of warfare, hunting, and the social mechanisms involved in procuring raw materials. Ethnographic observations and archaeological data suggest that flaked-stone points were designed (1) for hunting ungulates, or (2) for use against people. The distribution of points through time and space consequently provides evidence for conflict, and those aspects of subsistence in which they played a role. Points were commonly made from obsidian, a volcanic glass with properties that allow sources to be identified with precision. Patterns in obsidian procurement can therefore be employed to address socioeconomic interactions. By the 18th century, horticulturalists were present in only a few southern Arizona locations. Irrigation communities were more widely distributed during the Classic Period; the causes of the collapse of these communities and relationships between prehistoric and historic indigenes have been debated for centuries. Data presented here suggest that while changes in material culture occurred, multiple lines of evidence for cultural continuity from the prehistoric to Historic periods are present. The O'Odham creation story suggests that the population fluctuated over time, and archaeological evidence supports this observation. It appears that alterations in cultural practices and migrations occurred during intervals of low population density, and these fluctuations forced changes in political, economic, and social relationships along the middle Gila River / Dissertation/Thesis / Ph.D. Anthropology 2010