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The Institute for Advanced Technology (IAT) has conducted, and continues to conduct, a broad program to investigate the penetration characteristics and lethality of rod penetrators. The IAT's investigations are experimental, analytical, and numerical and are concerned primarily with slender rods impacting armor steel and ceramic targets at hypervelocity that is, above about two km/s. This report summarizes the results developed in representative examples of these studies that supported the U.S./IiK Project Arrangement. The work accomplished supports items a), b), and c) of the agreed-upon SOW. Each summary is accompanied by a bibliography listing relevant publications generated at the lAT and elsewhere.

The preliminary design of 8.5-inch ID, statically and internally heated hydrogen or helium shock tunnel driver is described. The driver is designed for a maximum performance of 1000 degrees F and 30,000 psi and will provide true temperature and pressure simulation of the air breathing propulsion system corridor. The heat transfer from the heater rods is considered and the results used to calculate the heating cycle and the temperature distribution history of the driver structure. A heating time of from one to two minutes is predicted. A preliminary design of the driver is presented which employs a liquid layer between the potentially embrittleable driver liner and the pressure shell. The temperature distribution predictions are employed to calculate the combined thermal and mechanical stresses in the structure. Finally, the preliminary design of the heater structure, liquid layer, seals, and double diaphragm section is given. (Author)

A study has been performed to determine the optimum, practical high-energy driver technique to be employed with the Air Force Aero Propulsion Laboratory 120-inch shock tunnel. The aerodynamic performance and engineering design and feasibility of several candidate techniques have been investigated. An internally and statically heated, 6-inch ID driver tube, employing hydrogen at a maximum pressure of 30,000 psi and a maximum temperature of 1000 F is recommended as the optimum, practical system. Such a driver will provide true speed, pressure, and temperature simulation along the corridor. Moreover, the engineering design of the heater, seals, diaphragm, and safety system are all within the current state-of-the-art, while the problem of hydrogen embrittlement of the driver tube appears solvable.

Media planning has heretofore been restricted, by and large, only to the consideration of average frequency. A recently developed mathematical model explicitly considers both cumulative duplicating audiences over a variety of time periods and the simultaneous selection and scheduling of media. This model thus required the development of methods for handling such nonlinear concave aspects of audience characteristics within a linear programming model and for generating distribution of frequency data within the computational processes of the model. This is done by means of logarithmic transformations and, for the discrete distributions of frequencies, by log-normal approximating devices. Each of these two techniques is important in its own right as a type of method which may be employed in a wide variety of modelling or computational situations. Thus, because neither of these techniques is restricted to the area of media planning per se, it seemed worthwhile to present them on their own terms. (Author)

A goal programming model for selecting media is presented which alters the objective and extends previous media models by accounting for cumulative duplicating audiences over a variety of time periods. This permits detailed control of the distribution of message frequencies directed at each of numerous marketing targets over a sequence of interrelated periods. This is accomplished via a new logarithmic non-reach device and a continuous lognormal generation of the discrete message frequencies. (Author)