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Command and noise signals expected to operate on specific control systems are often only scantily known at the design stage. This paper considers some of the problems which may arise in choosing a system transfer function when supplied with such inadequate information. A first order linear filter has been considered, and for synthesis purposes both command and noise signals have been represented by flat power spectra. The total power content and bandwidth of both signals have been varied, and the optimum transfer function for the various combinations determined by using the mean square error criterion.
With the above assumptions, it is shown that under the circumstances most likely to be met in practice, and in the absence of more specific information, a time constant of one-quarter of the inverse of the expected command signal bandwidth will yield reasonable mean square error performance. [ABSTRACT FROM AUTHOR]

This paper describes briefly the context in which a portable system for recording certain aspects of drilling performance is being developed. Particular emphasis is placed on a time recording channel in which a sensing element attached to the quill of the machine conveys signals from the translatory feed motion to a sequential-event timer and recorder (SETAR--after the design of N. T. Welford).
Some discussion is devoted to indicating how the reliability of such a system is largely dependent on the method of collecting, transmitting and recording for subsequent analysis the excitation signals. [ABSTRACT FROM AUTHOR]

Analyzes the evolution of signaling systems. Importance of communication in social behavior; Role of deceit in the evolution of social interactions; Definition of function and effect.

The performance of subjects (Ss) receiving contingent feedback in an eyes-closed alpha enhancement setting was contrasted with changes in alpha of Ss receiving random feedback and no feedback. In addition, comparisons were made between: 1) binary and continuous feedback signals; 2) integrated and criterion alpha as dependent variables; and 3) eyes-open and eyes-closed alpha enhancement tasks. It was found that: 1) Increases in emitted occipital alpha under eyes-closed conditions are related to contingent reinforcement. 2) Proportional feedback was most efficient in the rapid development of eyes-closed training. 3) Larger changes in alpha were seen during eyes-open than during eyes-closed training. 4) Binary feedback appeared to be more efficient in increasing eyes-open alpha response. 5) No relationships between the ability to perform the eyes-open and eyes-closed alpha enhancement tasks were found within Ss. [ABSTRACT FROM AUTHOR]

The article focuses on a study carried out in cooperation with British Rail to analyze the problems of railway signaling. British Rail are currently investigating continuous track-to-train communication, in parallel with this, studies are required of the use to which this may be put in connection with control of railway traffic. The traffic flow within a railway network is not amenable to analysis using classical mathematical methods because of the complexity of the network, the number of traffic types, and the random nature of the inevitable traffic disturbances that will occur. In considering the introduction of new signaling regimes and strategies of control of train speed and acceleration, the objectives that may be achieved has been classified under the broad headings outlined in the article. In the case of electrified lines, power demand peaks may be similarly minimized over the area covered by any given supply entry, by scheduling the actual times of acceleration and retardation of trains.

We consider a one-way street that intersects ii one-way (side) streets. Traffic approaching the first street is steady as are the flows on all side streets. Traffic signals are idealized as perfect on-off switches and traffic is treated as a fluid moving with a constant velocity on the main street. Total delay and total number of stops are evaluated for several types of signal coordination schemes. Some conclusions are: 1. For any given common cycle time and given splits at each inter- section, there is a choice of offsets (phases) that simultaneously minimizes both the total delay and stops, but it is not necessarily the one that produces a `through band' of maximum bandwidth. 2. There are signal settings for which some signals operate on half or a third the cycle time of other lights, which give a main Street delay equal to that for the optimal common cycle time setting but give less delay to the side street. 3. Similar models are commonly used to find maximum through bands for two-way traffic, but it is not obvious that this is a suitable objective even for one-way streets. [ABSTRACT FROM AUTHOR]

In order to ascertain whether neighboring intersections can be effectively coupled on the basis of traffic behavior, observational information on vehicular platoons was collected at four sites in London, England. This information is analyzed with particular emphasis on the phasing or synchronization of neighboring inter-sections for minimum delay. At each of the four sites studied, arrival time data was collected at four positions downstream from the signalized intersection from which the vehicular platoons were emerging. This data gives a measure of how platoons diffuse as they move from one intersection to the next. The analysis indicates that the diffusion process can be taken into account in the setting of signals. In particular, total delay in vehicle-hours per hour of green as a function of offset time is calculated, and in turn, the optimal offset time that would minimize delay is shown to be a linear function of the distance from the issuing traffic signal. [ABSTRACT FROM AUTHOR]

A technique for approximating the best linear predictor of a noise-distorted signal is presented. The technique is applicable when the signal is stationary with a spectrum which is highly concentrated around known or estimated frequencies, or when the signal is an accumulating sequence whose "spectrum" has poles at these frequencies. The noise must be stationary, but its spectrum need only be known or estimated at the above mentioned frequencies. The time parameter is assumed to be discrete. Computer-generated data are then used to obtain an idea of the "robustness" of the technique. [ABSTRACT FROM AUTHOR]

A laboratory-developed analog signal processor, driven by a conventional polygraph recorder and associated signal conditioning devices, provides automatic heart beat-by heart beat preprocessing of various cardiovascular function for input to a laboratory type minicomputer. The technique of preprocessing individual functions, integrated with the minicomputer system which includes an A/D converter and teletype as input output peripherals, provides a low-cost data acquisition and reduction system for the on-line computation and analysis of cardiovascular functions in experimental research applications. Such preprocessing more efficiently uses the minicomputer's memory to handle large amounts of information since the digitized data is in the form of one data sample, per function, per heart beat. Preprocessing analog data provides a low density data format and simplified software programs that are ideally suited for the utilization of a minicomputer in this on-line application. [ABSTRACT FROM AUTHOR]

Fifty-four Ss were divided into three instructional groups. One group was instructed to increase their heart rate (HR) every time a signal was presented; a second group was told to decrease their HR; and a control group was not instructed to change their HR in any direction. Results indicate that Ss can increase or decrease their HR in the absence of externalized feedback. These HR changes do not appear to be mediated by respiration or skin resistance variations. In addition, Ss were divided into groups on the basis of their APQ scores. The group with middle APQ scores displayed more HR control in both directions than Ss with high or Iow APQ scores. The study was replicated with 42 Ss and results support the HR increase but not the HR decrease findings. [ABSTRACT FROM AUTHOR]

The article examines the heart rate component of the orienting reflex to novel and signal the stimuli in nonretarded and retarded individuals on chronological age. The results show that the nonretarded and retarded individuals did not differ in their response to a novel stimulus. However, their response to the signal stimulus differ. The findings support the theory that retarded individuals suffer from a defect in attaching signal value to stimulus events.

This article describes a method of smoking reduction based on the theory that smoking is a learned habit controlled by specific environmental cues. To break the connection between these cues and the smoking response, the method requires the individual to smoke on a new cue, presented at random times by a portable signaling device. The substitute cue is initially set at the smoker's normal rate and then gradually phased out. Results of a study to test the feasibility of the method indicate that people can follow the program and reduce their smoking without other forms of therapy. [ABSTRACT FROM AUTHOR]

The article discusses the role of a controller in managing a system and the mode of communication used to transmit orders. The controller's purpose is met by transmitting a signal to the system instructing that particular operating characteristics should be abandoned in favor of others. For control to be effective, the system must react to the controller's signal. The types of signals used by a controller are listed, including continuous signals, discrete recorded signals, and discrete unrecorded signals. The decision of which type of signal to use is typically determined by the circumstances of the control being utilized. The types of correspondence contribute to definitions of hierarchy that exist between controllers.

3 experiments were conducted with children to determine whether the effectiveness of a verbal event ("right") as an outcome could be influenced by experimentally manipulating its signal function. Each experimental had a parallel condition in which a neutral nonverbal event (light-bell combination) was submitted to identical experimental operations. In accord with earlier studies, both "right" and the nonverbal event were found to be ineffective as outcomes when they occurred without a prior instructional set or as discriminative signals. The results of the experiments were largely consistent with an interpretation of social reinforcer effectiveness which emphasizes the contextual signal properties of these events. Certain implications of the research for the problem of "social satiation" and the nonefficacy of social reinforcement events are discussed. [ABSTRACT FROM AUTHOR]

Focuses on the development of research on binaural hearing. Relation between sound localization and binaural analysis; Anatomical and physiological literature on binaural interaction; Consideration on how one can localize a source in a realistic environment with acoustic reflections, transient signals, head movement and the complication of integrating information sampled at different moments in time.

Presents information on folk gestures and sign languages. Occupations using gestures; Use of signals in sports; Nonvocal communication in military life.

The article critiques on an example cited by professor Steffan Linder related to the declining pleasures of the bed. The example appears in a chapter on the acceleration of consumption, an effect resulting from equilibrium adjustments to the increasing availability of goods. According to the author it rather seems an excellent example of the expenditure of time for purposes of communication, or looked at slightly differently, for the purposes of screening. It is the expenditure of time that is the signal, or slightly more generally, it is the fact that the activity takes time (in the case of the Noh play, a long time) that imparts signaling power to it. It is, of course, important that this time spent not be overwhelmingly enjoyable for everyone. The theme, then, which the author would like to pursue here, is the idea that the expenditure of time in economic and social interaction can function as a signal and that willingness to spend time can be and is used as a screening device.