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The DARPA Polymorphous Computing Architecture (PCA) program is a research initiative aimed at developing new computer architectures with a high degree of flexibility. Unlike current computer architectures that are rigid in nature, PCAs will have the capability to adapt ("morph") to match the problem being solved. This flexibility will allow higher overall system performance in a broad range of applications. MIT Lincoln Laboratory has defined a set of kernel benchmarks for the PCA program. The kernel-level benchmarks have been chosen to stress both computation and communication aspects of the architecture. The particular benchmarks chosen are based on the frequency of their use in current and future applications. They are drawn from the areas of signal and image processing, communication, and information and knowledge processing. Each of these areas imposes different processing requirements on the architecture in terms of operations performed and memory bandwidth required. This document describes a set of measurements of the PCA kernel benchmarks on a prototype PCA chip., Sponsored in part by Defense Advanced Research Projects Agency (DARPA). The original document contains color images.

A routine soil testing procedure for soil N mineralization is needed that is rapid and precise. Not accounting for N mineralization can result in over application of N, especially in soils with a history of manure application. Our objectives were to compare results from a recently proposed rapid lab procedure with i) long-term N mineralization under standard laboratory conditions, ii) actual forage N uptake from soil receiving dairy cattle (Bas taurus) manure in a two-year field study and iii) yields of various crops throughout Texas and Oklahoma. The rapid procedure is based on the quantity of CO2-C evolved for 24 hours under optimum laboratory conditions following the rewetting of dried soil. Results of the one-day CO2 procedure were highly correlated with soil N mineralized from samples collected in March of 1995 and 1996 from a manure study and with forage N uptake both study years. Residual inorganic N in the same soil samples was much more poorly correlated with forage N uptake. Results of the rapid procedure were also highly related to yields of ryegrass, grain sorghum, corn, and wheat in 1996 - 1999.

A high resolution, 20-level, primitive equation (PE) model of the California coastal region is initialized using temperature data acquired during the first California Transition Zone (CTZ) cruise from 6 to 12 July 1988 for the purpose of diagnosing the three-dimensional dynamically balanced flow field for the region. The major feature in the region during the cruise period was a strong meandering jet which flowed equatorward and offshore, oriented in a northeast to southwest direction. The quality of data acquired during cruise CTZR1 is sufficiently high to enable diagnosis of the horizontal (baroclinic) and vertical velocity field using the numerical model. The measured (ADCP) currents showed more details of the flow at deeper depths than the model, which showed a broader baroclinic flow at depth and a level of no motion near 300 m. The maximum surface velocities from model and ADCP cross-sections agreed to within 10 cm/sec except for leg G, in which ADCP velocity was greater than the model velocity by about 30 cm/sec. The sign of vertical velocity agrees very well with independent estimates made from bio-optical data; however, the magnitude calculated by the model is 30 to 60 times larger than that estimated from the bio-optical observations.

The report describes results obtained from applied loading of the wing surfaces of an F-102 aircraft.

The synthesis of threshold logic circuits from several points of view is presented. The first approach is applicable to resistor-transistor networks in which the outputs are tied to a common collector resistor. In general, fewer threshold logic gates than NOR gates connected to a common collector resistor are required. Synthesis techniques based upon the use of Boolean matrices are presented. In this case the goal of the synthesis is a network to realize a specified function such that the failure of any but the output gate can be compensated for by a change in the threshold level (and possibly changes in the weights of the inputs). In general, the ability to compensate for a failure requires the synthesis of a network with more gates than if no compensation were required. The net result is that the synthesis is an involved procedure. A mechanism for changing weights of threshold gates using a photo-diode matrix is presented. The design of the control system for an IBM type 350 disc file is presented as an illustration of the design of a practical system in which threshold logic is employed. The function of the control system is to position the read-write heads over the specified track of a specified disc to read in or to read out data. Less logic circuitry is required if threshold logic rather than NOR logic is used. (Author), See also AD-297 862.

A high resolution, 20-level, primitive equation (PE) model of the California coastal region is initialized using temperature data acquired during the first California Transition Zone (CTZ) cruise from 6 to 12 July 1988 for the purpose of diagnosing the three-dimensional dynamically balanced flow field for the region. The major feature in the region during the cruise period was a strong meandering jet which flowed equatorward and offshore, oriented in a northeast to southwest direction. The quality of data acquired during cruise CTZR1 is sufficiently high to enable diagnosis of the horizontal (baroclinic) and vertical velocity field using the numerical model. The measured (ADCP) currents showed more details of the flow at deeper depths than the model, which showed a broader baroclinic flow at depth and a level of no motion near 300 m. The maximum surface velocities from model and ADCP cross-sections agreed to within 10 cm/sec except for leg G, in which ADCP velocity was greater than the model velocity by about 30 cm/sec. The sign of vertical velocity agrees very well with independent estimates made from bio-optical data; however, the magnitude calculated by the model is 30 to 60 times larger than that estimated from the bio-optical observations., http://archive.org/details/adiagnosticstudy1094510803, Lieutenant Commander, United States Navy, Approved for public release; distribution is unlimited.