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The identification problem of systems with linear dynamics with state and observation noise is considered. An application to a Flight Control problem is indicated. (Author), Presented at the Southeastern Symposium on System Theory (3rd), held at Georgia Inst. of Tech., Atlanta, on 5-6 Apr 71.

The guide provides description of procedures used in an experimental project of the Air Force to identify, describe an document the problems of technological nature encountered or expected in the development of advanced systems or components. The objective of the project was to develop tools and procedures for improved R and D communications between R and D managers, technology users and the scientists and engineers.

One hundred of the most frequently referenced and historically interesting reports related to the detection of staphylococcal enterotoxins are annotated.

The purpose of the present experiment was to determine the effect of knowledge of results (KR) when introduced separately from any change in motivation. That is, the object was to determine how much of the improvement reported by Shvarts is due to a learning process specific to the stimulus used, and how much is due to a general excitation of cerebral centres, which according to Shvarts, transfers to the discrimination of other stimuli. The following changes in the procedures described by Shvarts were made. First, KR was intruduced some time after the effect of the motivation variable had been measured. These two variables were confounded in Shvarts' study. Secondly, to distinguish training effects from motivation effects, the level of discrimination was determined independently on a Landolt ring before and after the experiment, in which the training stimulus was a letter E. (Author), Reprint from Perceptual and Motor Skills, 18, pp. 505-508, 1964. (Copies not supplied by DDC)

The relative legibility of special symbols constructed from 5 x 7, 5 x 9, 7 x 9 and 7 x 11 dot matrices was determined. The special symbols were shown to one group of operators under nearly optimal viewing conditions. For two other groups of operators, symbol quality was degraded by vertically overprinting one symbol on another. The results indicated that symbol indentification was better for the 7 x 9 matrix than for the 5 x 7 matrix for both good and degraded display conditions. Symbol overprinting greatly impaired the operators' ability to identify special symbols. (Author), See also AD-850 380.

The approaches used in the identification of nonlinear systems from input-output data have normally assumed that the system is almost completely unknown, or that it is completely known with the exception of fixed number of unknown parameters. In this report it is assumed that the input-output relations for the nonlinear dynamical system under study are known with the exception of an unknown function which occurs in this representation. From a finite length of input data and noise corrupted output data techniques are presented which yield a maximum likelihood estimate of an approximation to the unknown function. Computer algorithms based on gradient and Newton-Raphson procedures are developed, and an example is presented. (Author), Doctoral thesis.

This report evaluates the use of the surface dynamics profilometer for measuring runway profiles. This evaluation showed that the surface dynamics profilometer meets all requirements for a system of this type and that for the first time runway profiles can be rapidly and accurately measured without removing the runway from operation for long periods of time. Modern aircraft, due to their large size, structural flexibility and higher take-off and landing speeds, can be excited into a resonant condition by runway roughness. Forces generated by the interaction of the aircraft and the runway can cause damaging stresses both in the aircraft structure and the runway pavement itself. Wavelength components in the runway profile that cause aircraft resonance often are difficult to locate. One method is to use the measured profile of the runway as an input to a computer simulation of the affected aircraft. (Author)

The major objective of the side-looking radar (SLR) Training Study project was to design and develop a programmed instructional course in SLR imagery interpretation that could be used with experienced photointerpreters or interpreter trainees in either a classroom or field setting. The program materials were developed and revised using the 'self-correcting' mechanism. Two major phases of testing were used during the development of each instructional sequence: (1) laboratory and (2) field. (Author)

An iterative procedure is presented which permits the determination of a rational transfer function in the Laplace transform variable s which is optimal with respect to given input and output time-functions. The optimal system of a particular order is defined as the one whose output when subjected to the known input function is nearest in the time integral square sense to the desired output function. The method is thus applicable to a number of problems involving the minimization of an integral square error. (Author)

Trans. from Priroda, 33, 1944.

The need for a device capable of measuring bearing rate is shown. Some specifications for such a device are set forth. Several possible means of obtaining bearing rate from continuous passive sonar bearings are then considered. The feasibility of one of these means is then studied in detail through the development of an initial and than a final prototype. A conclusion is reached that the final device as constructed performs adequately. Several recommendations for improvement of this final device are suggested. (Author)

Suppl. to AD-347 208.

The objective of the study was to evaluate the extent to which an existing electro-optical technique could improve the performance of image interpreters identifying tactical targets from degraded imagery. The interpreter performance of eight subjects using the Image Enhancing Microscope was compared to their performance utilizing conventional image interpretation techniques. Both accuracy and completeness scores were considered. The test imagery consisted of Minuteman missile sites in various stages of construction which was degraded in resolution and contrast. Evaluation of the enhancement technique yielded significantly inferior performance in comparison with conventional techniques. (Author)

The study for the Development of a Method for the Evaluation and Selection of Deep Ocean Load Handling Systems was conducted to assist the U.S. Navy in performing seafloor construction projects through consideration of operations involving equipment and transport of materials for load implantment. The study has accomplished four primary tasks: (1) The assemblage and organization of data; (2) The development of a mathematical model which is descriptive of a generalized total deep ocean implantment mission; (3) Translation of the data and model into a computerized method to enhance utilization; and (4) Validation of the method through application of selected case examples. The method provides the capability to evalute any selected deep ocean load handling system on the basis of critical mission parameters. This volume contains a synopsis of the study scope of the deep ocean load handling mission, analysis which was performed, and significant findings and general results of the study effort. A technical discussion is provided of the mathematical model inclusive of mechanization logic and evaluation factors. Formulation of the computer model defining format and utility subroutines is presented. (Author)

A new approach for a digital adaptive flight control system was developed. This approach consists of an explicit identification of the vehicle transfer function coefficients coupled with a control system parameter optimization to minimize an integral square error type criterion of performance. The investigation included theoretical studies which further developed the identification and parameter adjustment equations and established their effectiveness and the limits within which they are effective. These theoretical studies also established methods for the numerical integration which is needed in the identification and a search technique which is needed in the parameter adjustment process. Working equations which were used in the programming for the digital studies are included. The extensive all-digital and the hybrid simulation set up for this study is described. The all-digital simulation was useful in testing the sensitivity of the identification and parameter adjustment by taking numerous short runs under varying conditions. The hybrid simulation permitted testing the proposed methods in conjunction with realistic airframes in actual closed autopilot loops on realistic trajectories.