bluuebunny/crossref_metadata_2025 huggingface dataset:
Proprioception Variables as Determiners of Anticipatory Timing Behavior
Authors: Adams Jack A. , Creamer Lyle R.
Published: January 2017

Anticipatory timing, where the human operator initiates an accurate response before the actual occurrence of the environmental event, is one of the most striking and least studied aspects of skilled motor performance. An experiment was performed on temporal and control system variables that could influence the timing of responses in a tracking task. Verification was sought for a proprioceptive trace hypothesis that holds the time-varying proprioceptive after-effects of movements to be the internal trace that persists in time and cues the occurrence of a future response. Ninety-six subjects participated. A 2×2×2 randomized factorial design used two values each of movement amplitude, spring loading, and signal duration as a means of manipulating proprioceptive stimuli and their time trace. Results supported the hypothesis. Signal duration and spring loading of the control induced significant effects for the number of beneficial anticipations, but movement amplitude had no significant effect. It was concluded that proprioception has a role in response timing, in addition to its traditional one of informative feedback.
Dynamic Vision—The Legibility of Equally Spaced Alphanumeric Symbols
Authors: Lippert S.
Published: January 2017

A. trial study was conducted on the ability of observers to identify moving targets consisting of alphanumeric symbols. The targets, randomly assigned, were regularly spaced on an endless belt which was viewed from a constant distance. The target subtended an angle of 39 min. The space between targets subtended an angle of 51 min. The targets moved vertically from top to bottom in the frontal plane. Six subjects were tested on criteria of zero legibility and 100 per cent legibility when the targets were viewed through apertures 2 in. wide and 2 in., 8 in., and 20 in. high.

Performance was measured in terms of the angular velocity of the targets past the observer's eyes. As aperture height increased both legibility criteria could be met at higher angular velocities of the stimulus materials. The mean angular velocities for the zero legibility criterion were approximately three times as great as for the 100 per cent legibility criterion.
Monitoring of Complex Visual Displays: IV. Training for Vigilance
Authors: Adams Jack A. , Humes John M.
Published: January 2017

An experiment was performed to test the hypothesis that knowledge of results (KR) in a vigilance task can be used as a training technique that will transfer positively to subsequent non-KR sessions where feedback is absent. Three groups, fifteen subjects each, participated in a visual monitoring task for four sessions of three hours each. One group received KR about response proficiency after each response in the first two sessions and a second group received only a neutral remark each time from the experimenter. The final two sessions were standard vigilance tasks without feedback. A third control group had the standard task throughout. The KR group had reliably superior performance on all sessions although within-session vigilance decrement was uninfluenced. The neutral stimulation group did not differ from the control condition. It is suggested that KR administered in a training situation can produce improved vigilance during actual system use where KR is absent.
Increasing Voice Communication Channels Using Man's Binaural Listening Capability
Authors: Rappaport Maurice
Published: January 2017

Sending voice messages over pairs of channels makes available more channels for communication than would be possible if channels were used in a conventional manner and only one message was sent over one channel. Although this means that all channels under the dual channel system must carry several messages simultaneously, it is shown that for subjects wearing earphones, message intelligibility remains remarkably higher than if the same number of messages are sent over a single channel. The superiority of the dual channel method is attributed primarily to the unique capability of the human ear-brain system to perceive diotic signals as being located in the center of the head while all dichotic signals are perceived as being off to the side of the head. Where seven voices are talking simultaneously intelligibility of messages under the dual channel method of transmission is about 94 percent as compared to 11 percent under the single channel method.

Practical implications of these findings for a number of military and civilian communication situations are discussed.
A Rating Scale for Damage Evaluation
Authors: Braunstein Myron L. , Richard T. Been , Piazza Mildred H.
Published: January 2017

An aircraft damage scale was constructed from a set of photographs of accident-involved aircraft by the Method of Equal Appearing Intervals. An experimental evaluation of the scale demonstrated its usefulness in increasing the reliability and accuracy of aircraft damage evaluations made from photographs. Other applications of this scaling technique are discussed.
The KB System: A Modular Control Panel Concept
Authors: Harkins William H.
Published: January 2017

This report describes the design and development of an integrated system of manually operable switch modules and related keyboard and control panel components called the KB System. The size of the basic module was based on the standard center-to-center spacing of keys in a conventional keyboard. The system of components and mounting structure based on this module can be assembled in an unlimited number of arrangements to satisfy widely varying man-machine system control and display requirements.
The Action Office
Authors: Propst Robert L.
Published: January 2017

Several years of self-directed work experience in his own office resulted in the development and application by the author of a new approach to the design and arrangement of office equipment, and a resulting increase in alertness, productivity, and fluency in his work. These outcomes led to an association with Herman Miller, Inc. in 1960 to conduct research to obtain more definitive and conclusive information on how office elements influence the office worker, and how these elements may be redesigned to improve health and productivity. This effort involved four major aspects-actual experience with prototype offices and equipment, obtaining information from pertinent disciplines, studying office patterns of exceptional performers, and testing and evaluation of office environments. The study results indicated that most prevailing offices and furnishing systems are substantially too restrictive and inflexible, and tend to ignore and stifle prime human capabilities. However, there are indications of an awakening to the importance of new office facility concepts in meeting the growing needs of day-by-day change and modifications of environmental effect.
Packaging for People
Authors: Short Donald , Stovell Robert J.
Published: January 2017

The case histories presented in this paper illustrate the various marketing, technological and human factors requirements which influence the design of a relatively simple everyday artifact, the consumer package. During the past twenty years, package design has grown from modest beginnings to become one of the major areas of industrial design activity. Concerned with the protection, distribution, sales and use of products, the designer of the package must accommodate a number of different human interfaces, placing strong emphasis on the satisfaction of emotional as well as physical needs. Some packaging requirements are amenable to rational design solutions and the application of established human engineering criteria, but despite the growing use of a variety of research techniques, packaging relies, more than most other areas of industrial design, on limited empirical findings and the designer's intuitive interpretation of requirements.
Design of Rapid Transit Equipment for the San Francisco Bay Area Rapid Transit System
Authors: Sundberg Carl W. , Ferar Montgomery
Published: January 2017

Automobile traffic is threatening to overwhelm the cities of the San Francisco Bay Area, and an advanced mass transit system is being built by the Bay Area Rapid Transit District (BARTD) to help alleviate this problem. This article describes the design and development of the passenger vehicle for this system. BARTD system requirements and car design criteria are discussed, and the conceptual design and detailed development of passenger accommodations, environmental control provisions, lighting, ingress/egress, visibility and appearance design featurea are presented. The requirements for and the detailed design of the train attendant's pod are also discussed. A prototype car has been designed with primary emphasis on those human factors considerations that are expected to induce 200,000 commuters to use the system in preference to private automobiles. Public reactions to the prototype vehicle will be employed to refine and improve upon the design prior to its introduction into service in 1971.
Bayesian Aspects of Trouble Shooting Behavior
Authors: Bond Nicholas A. , Rigney Joseph W.
Published: January 2017

Thirty-nine Navy technician trainees filled out a symptom-malfunction matrix on a blocking oscillator circuit. The technicians then attempted to solve six troubleshooting problems in the same oscillator circuit. The particular sequence of checks used by each man on each problem was combined with his symptom-malfunction matrix, via a Bayesian algorithm, to yield computer estimates of failure likelihoods for each component. The computer program predicted actual parts-replacement behaviors in about half of the cases. Those technicians who start out with valid symptom-malfunction matrices are more likely to resemble the Bayesian processor.
The Feasibility of a Helmet-Mounted Sight as a Control Device
Authors: Nicholson Robert M.
Published: January 2017

The purpose of this research was to investigate the practicality of a helmet-mounted sight as an operational element in a quick-reaction bore-sighting system. A three-phase experimental program was conducted to determine the human capabilities with the helmet-mounted sight. In a laboratory environment sighting accuracies were obtained on both static and moving targets. Field test data were obtained during high-speed, low-altitude flights. The series of tests indicated that the accuracy of the sighting process can be expected to vary between a fraction of a degree and four degrees depending on target angular rate and the target sighting angle.
Effects of Display Magnification, Proprioceptive Cues, Control Dynamics and Trajectory Characteristics on Compensatory Tracking Performance
Authors: Smith Russell L. , Garfinkle David R. , Groth Hilde , Lyman John
Published: January 2017

An experiment was performed on the NOTS-UCLA heavy inertia tracking simulator to assess effects of display magnification, proprioceptive cues, displacement aiding, trajectory characteristics and trajectory direction on tracking performance. Particular attention was paid to interactions among these variables. The results showed that: (1) 5x magnification significantly decreased tracking error compared to tracking without magnification; (2) proprioceptive cues related to both azimuth and elevation significantly improved performance; (3) velocity plus displacement-aiding control dynamics (time constant = 0.1 sec) produced significantly lower error scores than unaided velocity control dynamics (time constant = 0.0 sec); (4) since no crossover tendencies were found, the effects of the varables appear to be independent.
Detection and Identification of Colored Smoke
Authors: Weasner M. Harold , Carlock Jack
Published: January 2017

A field study was conducted to determine the rates of detection, identification, and location of colored smokes by ground and aerial observers. Distances from observers to smoke varied between 500-10,000 meters. Red, yellow, green, violet and white smokes were generated by initiating U.S. Army Standard M8 and M18 smoke grenades. Nine volume-duration combinations of smoke were tested. Volume of smoke was controlled by initiating various numbers of grenades (1, 2, or 3) simultaneously. Duration was controlled by initiating various numbers of grenades in succession so as to give a continuous smoke. The larger volume-duration combinations (e.g., 2-3.and 3-3) yielded the highest rates of detection, identification, and smoke location. In terms of overall effectiveness, the best volume-duration combination was 2-3. The most effective color was white, then red, while violet was the poorest.
Airborne Displays for Flight and Navigation
Authors: Roscoe Stanley N.
Published: January 2017

This paper deals with certain types of airborne displays, specifically, those used in navigating and flying aircraft. Consideration is given to the nature of the crew's flight task, to certain principles of flight display, and to some of the experimental evidence bearing on principles of display.
Prediction of Muscular Endurance (Work Performance) From Individual Differences in Initial and Post Training Increments in Static Strength
Authors: Smith Leon E. , Edwards Donald K.
Published: January 2017

Forty college men were given tests for static strength and strength endurance prior to an isotonic strength training program. Experimental results indicate that individual differences in static strength are a poor criterion in the prediction of muscular endurance. Following an increase in static strength resulting from isotonic strength training pre-training static strength and post-training strength increments are not indicative of an individual's performance in a hand grip endurance activity.
Assessment of the Fidelity of Dynamic Flight Simulators
Authors: Mudd Samuel
Published: January 2017

The evaluation of dynamic flight simulators is considered from the standpoint of the efficiency and validity of the currently used pilot evaluations and assessment techniques. A set of requirements for an ideal fidelity measurement technique is presented, followed by a comparison of the two general approaches to fidelity measurement, the analytic and the empirical, with reference to those requirements. A hybrid method which involves the use of pilot psychomotor responses rather than verbal responses is introduced. This technique retains the subjective characteristic of rating scales, but provides information of an analytic nature that is more amenable to engineering analyses. Problems involved in the development of the technique are considered.
Visual Detection Probability of “Sonar” Targets as a Function of Retinal Position and Brightness Contrast
Authors: Vallerie Leroy L. , Link James M.
Published: January 2017

A study was carried out in the laboratory to determine the detectability of visual sonar targets as a function of retinal position and brightness contrast using a simulated sonar scope. Nine different retinal positions were investigated under photopic conditions of illumination. The target was approximately square and subtended 24 minutes of visual arc on a side. Average peak intensity of the sweep, which formed the target background was 9.12 FL. The results of the study were presented in terms of probability of detection curves. Equations were developed for determining the probability of detection given the target's normalized brightness intensity, expressed in Log ΔI/I, and its angular distance from the point of fixation.
Joystick Dynamics
Authors: Perry Lee Barbour , Birmingham H. P.
Published: January 2017

In the light of the critical importance of considering the dynamic contributions of system elements to total system performance, the dynamic characteristics of joystick controls are discussed. The transfer functions of four common joystick types are derived, and an example illustrates the effect of joystick design on system performance.
The Design for an Optical Rate Display
Authors: Griffin Patricia Anne
Published: January 2017

There is a definite need for optical rate displays, especially in the critical task of landing aircraft. In the course of developing such a display, other unique characteristics evolved that are significant improvements to the information provided by many of the extant position, position error, and rate displays. There are many possible applications and generalizations of the principles utilized for this particular display in this specific problem to other man-machine control problems requiring precise manipulations.
The Prime Technical Information Source—The Local Work Environment
Authors: Hodges J. D. , Angalet B. W.
Published: January 2017

This paper is a report of one of the conclusions of the DOD User-Needs Study, Phase II—Flow of Scientific and Technical Information Within the Defense Industry (Contract DSA-7-16244). This major study conclusion is that the local work environment is an important and necessary source of scientific and technical information. The current trend, however, is toward greater reliance on this information source; and certain aspects of the informal and formal information system experience seem to be reinforcing the local, informal system utilization and lessening the use of formal systems. The understanding of the needs of the user and an organized effort by the formal system to respond to these needs is the course that must be followed if the technical information system and its personnel are to fill a more meaningful position within the scientific and technical information flow process.
Individual Differences and Intra-Individual Variability in Motor Performance under Continuous-Practice Conditions
Authors: Stelmach George E.
Published: January 2017

The effect of practice on individual differences, intra-individual variability, and remoteness was studied in performance during eight minutes of continuous practice on a large muscle motor task. Individual differences (true score variance) revealed a slight increase during the practice session, while the intra-individual variability remained relatively unaffected by massed practice. When the improvement in performance was removed by examining the relative variability, both sources of variance increased. The effects of an increasing number of interpolated trials on the inter-trial correlations revealed that with increasing amounts of remoteness, the inter-trial correlations decreased.
The Effect of Color Coding on Performance of an Alphabetic Filing Task
Authors: Konz Stephan A. , Koe Bruce A.
Published: January 2017

Color coding in filing tasks has often been accepted as superior to no color coding. The purpose of this experiment was to explore the effect of filing names, typical of a telephone directory, color coded on the first letter and on the second letter of the last name. A no-color-code condition was used as a control. Rate of production, number of errors, magnitude of errors, and user preference served as criteria.

Twenty-two subjects filed 375 appropriately color-striped IBM cards into a box of IBM cards appropriately coded. The rate of performance and subject preferences indicated that the second-letter code was better than the other two conditions. Based on quantity of errors, the first- and second-letter codes were significantly (α < .05) better than the no-color-code condition. Considering the magnitude of errors, the first-letter code was significantly better than the two other codes. The results of this experiment suggest a color-coded filing system based on a simple first-letter scheme would significantly reduce the magnitude and quantity of high inconvenience cost errors over the conventional no-color-code system …
Desirable Dimensions for Concentric Controls
Authors: Bradley James V.
Published: January 2017

A series of experiments was performed to determine the minimum allowable dimensions of circular, non-detent knobs, mounted on concentric shafts, when frequent inadvertent operation of adjacent coaxial knobs cannot be tolerated. A standard setting was used, and measures were taken of reach time, turning time, and inadvertent touching of adjacent coaxial knobs. Manipulated variables were thickness, diameter, and difference in diameter between the operated knob and the adjacent knobs. It was concluded that if three knobs are to be concentrically ganged and if the middle knob is about 2 in. in diameter, (a) the diameter of the front knob should be at least 1 in. smaller and that of the back knob 1¼ in. greater than that of the middle knob, and (b) the front and middle knobs should each be ¾ in. thick, whereas the back knob may be as thin as ¼ in.
Optimum Knob Crowding
Authors: Bradley James V.
Published: January 2017

Reach time, turning time, and inadvertent touching of adjacent controls (i.e., errors) were measured while a standard setting was made with one of several closely spaced knobs. The variables manipulated were spacing between knobs, knob diameter, and knob configuration.

Performance improved rapidly with increasing distance between knob edges up to an interperipheral distance of 1 in., after which performance continued to improve but at a much slower rate. For equal amounts of panel space consumed by several closely crowded knobs, ¼-in. diameter knobs were more nearly error free than were the larger diameter knobs tested. For equal distances between knob edges, however, performance improved with increasing knob diameter. These results apply only to knobs capable of being operated by moderate torque.

It was found that the frequency with which a crowding knob is inadvertently touched is strongly affected by the angular position which it occupies with respect to the operated knob but is practically independent of the presence of other crowding knobs at the same distance from the operated knob.
The Effects of Ambient Noise on Vigilance Performance
Authors: McCann Patrick H.
Published: January 2017

The effects of continuous noise versus intermittent noise on subjects performing an audiovisual checking task were examined. Although there was no difference between the effects of the two kinds of noise on total errors, intermittent noise produced a larger number of omission errors than did continuous noise. There were no differences in overall vigilance performance between male and female observers. There was a decrement in performance with time-at-work typically found in other vigilance studies.
Effect of Vibration on the Operation of Decimal Input Devices
Authors: Dean Robert D. , Farrell Richard J. , Hitt James D.
Published: January 2017

A series of three experimental studies was conducted to determine the relative effects of mechanical vibration on decimal input performance. Six input panels were used, involving four basic types of controls: push buttons, toggle switches, rotary switches, and thumbwheels. Subjects were engineer/pilots who were given the task of inserting eight-digit decimal numbers. Twelve subjects were used in the first and second studies, ten in the third. The dependent measures were speed, accuracy, preference, and estimated speed and accuracy. The first study was conducted in an office environment. The second study was conducted under a control condition and 0.5 RMSg (2–30 Hz.) random vertical vibration; the third study was conducted under five levels of 2–30 Hz. random vertical vibration (0.0, 0.2, 0.4, 0.6, and 0.8 RMSg). No single device was best in terms of speed, accuracy, and preference. The overall effect of vibration was to degrade performance.
Operational Measures of Aircraft Carrier Landing System Performance
Authors: Brictson Clyde A. , Ciavarelli Anthony P. , Wulfeck Joseph W.
Published: January 2017

Measures of final landing approach performance during day and night aircraft carrier recovery are analyzed and interpreted. Approximately 1,800 recoveries were recorded for experienced and inexperienced pilots across four aircraft carriers, six different types of jet aircraft, and various environmental conditions. The salient features of the findings are reviewed and evaluated for their operational implications, with special emphasis on night carrier recovery. Practical applications of the performance data to visual landing aid design and evaluation, pilot and landing signal officer training, and aviation safety are discussed. Empirical landing performance criteria are developed and used to predict the probability of landing success as a function of deviations in final approach performance.
Life and Death
Authors: Parsons Henry M.
Published: January 2017

A “systems study of mankind” should incorporate analyses of the cost/effectiveness of life and human factors analyses of death. Various methods have been adopted for placing a dollar value on human life. Human factors studies can attempt to prevent loss of life in vehicular accidents, incorporate the number of lives saved as a criterion of the benefits of improvements in defense systems, examine the nature of behavior governed by deterrence, and investigate some of the complexities of population control. Systematic investigation might also be conducted into the parameters of death. An ecological projection suggests that a nuclear war may occur to counteract the disequilibrium of nature resulting from technology, including the population explosion.
The Standardization of Human Factors Data
Authors: Parsons Stuart O. , Lebach John L.
Published: January 2017

Thirty-two human factors data forms used by six organizations participating in the definition of the NASA Apollo Applications Program were analyzed to develop a standard reporting technique compatible with computer data processing methods. The analysis provided a matrix of 17 data and document types by 43 content areas. Six user organizations indicated their information requirements by filling out the matrix sheet. High-frequency data items formed the basis for developing a single format that can be used initially in any manned space task equipment analysis, maintenance analysis, and training requirements analysis.
Is Motion Needed in Flight Simulators Used for Training?
Authors: Cohen Edwin
Published: January 2017

Although flight training curricula demand that pilots learn to disregard bodily sensations of motion, aircraft motion can be an important source of information to pilots, and sometimes can also degrade pilot performance. Considerable evidence is adduced that motion in flight simulators produces significant training benefits, but there is a scarcity of data on the consequences of different degrees or methods of motion simulation. To produce the sensation of miles of aircraft motion with a few feet of simulator motion requires consideration of various aspects of human sensitivity to motion. Some of the complications in obtaining motion-threshold data are discussed, and two illustrations of the utilization of these data in optimizing motion simulation are given.
Attitudes Toward Driving Safety and Their Modification
Authors: Schuster D. H.
Published: January 2017

This paper reviews and discusses the measurement of attitudes toward traffic safety and the attempts to change these attitudes and related driving behavior. Psychological testing of such attitudes and personality characteristics is fairly well developed and there are some instruments of good reliability and useable validity. Efforts to modify driver attitudes and behavior are inconclusive and only mildly encouraging. Considerable research needs to be done before the attitudes and behavior of drivers can be changed to improve traffic safety in the United States.
Determining the Detectability Range of Camouflaged Targets
Authors: Guttmann Henry E. , Webster Robert G.
Published: January 2017

This paper describes a quick economical method for determining the maximum range at which camouflaged targets can be detected. The method produces results which agree within 10% of those obtained by conventional psychophysical methods.
A Biokinematic Model for Workplace Design
Authors: Kilpatrick Kerry E.
Published: January 2017

The spatial relationships between an operator and his working environment must be evaluated early in the design process. To aid the designer in this evaluation, a computerized biokinematic model of the operator has been developed to determine reach feasibility and predict the configuration of aseated operator performing a task sequence. The development, validation, and applications of the model are discussed.
Results of an Ergonomic Investigation of Large-Space Offices
Authors: Nemecek Jan , Grandjean Etienne
Published: January 2017

Ergonomic measurements of noise, lighting and room climate were made in 15 large-space offices in Switzerland. At the same time, 519 employees were given a questionnaire about working in such offices (continuation of work, distractions, disturbances, interpersonal relations, communications, etc.). The correlations among measures indicated the factors that have special influence on the judgments of the large-space office. The results form an objective, usable decision base for the selection and planning of an office building.
Design of Industrial Jobs a Worker Can and Will Do
Authors: Swain Alan D.
Published: January 2017

Ergonomists working in the military area need to modify some of their assumptions about operator (or worker) behavior when they transfer to work in the industrial area. The goal of the ergonomist in the latter area should not be job simplification as it often is in the former area. Job simplification is a frequent outcome of human factors approaches which consider only what a man can do. In the industrial setting, cost-effective attainment of long-range industrial system efficiency and effectiveness cannot be achieved unless consideration is also given to what a man will do. This paper describes some of the factors important to the ergonomist in industrial work and suggests that their consideration is especially important if the ergonomist is to consider himself as a systems designer rather than a “knobs and dials” man.
Establishing the Boundaries of a Paradigm for Decision-Making Research
Authors: CANNON-BOWERS JANIS A. , SALAS EDUARDO , PRUITT JOHN S.
Published: January 2017

In recent years a paradigm shift in decision-making research has occurred. Modern decision researchers are more interested in studying decision making as it occurs in the so-called real world under naturalistic conditions. As such, the naturalistic decision-making (NDM) movement has seen growing support in recent years. Our contention is that in order for a new paradigm of NDM to flourish, it is essential to define carefully and completely the nature of decisions that are of interest to investigate. Once this is done, it is then possible to determine the psychological processes and strategies that decision makers use to cope with this subset of naturalistic decisions and to establish acceptable methods of study. Given this need, the purpose of this article is to examine the concept of NDM as it has been treated in past work and to refine and expand this conceptualization.
Attention Distribution and Decision Making in Tactical Air Combat
Authors: ENDSLEY MICA R. , SMITH ROBERT P.
Published: January 2017

Tactical decision making in the air combat environment requires the rapid processing of large amounts of data in a complex and unpredictable environment. To investigate decision making in this domain, we conducted a study in which 10 experienced fighter pilots provided tactical decisions and performed a target replacement task on a tactical situation display showing a wide variety of tactical situations based on the de Groot memory paradigm. Results were analyzed to determine features related to pilot attention distribution in processing tactical situation displays and their correspondence to tactical decision making. Evidence is provided for the effect of target quantity, target location, and overall target density distribution on decision making and attention. In addition, substantial variation in decision making was found between participants. Systematic biases in attention were also discovered which have implications for decision making in combat situations. Evidence of chunking in processing the displays was also explored. Results indicate that although pilots appeared to chunk targets in a manner similar to experts studied in other fields, the criterion used for determining chunking in these studies may not be valid.
Research with Patriot Air Defense Officers: Examining Information Order Effects
Authors: ADELMAN LEONARD , BRESNICK TERRY , BLACK PAUL K. , MARVIN F. FREEMAN , SAK STEVEN G.
Published: January 2017

In an experiment using the Patriot air defense training simulator, we found that the order in which the same information was presented to experienced Patriot officers significantly affected their probability estimates, identification judgments, and engagement decisions. In all cases the results represented a primacy effect, contradicting the recency effect predictions of the Hogarth and Einhorn (1992) model. In the present study we found that early in an aircraft's track history, the order effect is caused by the overweighting of prior information; later in the history, the late order effect is caused by participants reinterpreting the meaning of information based on what preceded it. These findings help to explain the differential effectiveness of a proposed display and the importance of naturalistic research for testing the generality of models of decision making.
Supporting Perception in the Service of Dynamic Decision Making
Authors: KIRLIK ALEX , WALKER NEFF , FISK ARTHUR D. , NAGEL KARIN
Published: January 2017

Skilled performers in complex environments rely heavily on heuristic strategies to cope with the time pressure and complexity of dynamic tasks. We suggest that the use of task simplification strategies based largely on perception and pattern recognition is fundamental to the novice-expert shift in dynamic decision making. We therefore suggest that interface training interventions should support the development of highly effective and robust heuristic strategies, rather than the development of more abstract, cognitively intensive strategies. A pair of empirical studies are presented that investigated the benefits of training interventions aimed at supporting perceptual and pattern-recognitional activities in dynamic environments. Results suggest that the acquisition of skilled performance in dynamic environments can be accelerated by supporting perceptual activities in the service of dynamic decision making. Implications of these results for training, aiding, and interface design are discussed.
Effects of Workload and Structure on Team Processes and Performance: Implications for Complex Team Decision Making
Authors: URBAN JULIE M. , WEAVER JEANNE L. , BOWERS CLINT A. , RHODENIZER LORI
Published: January 2017

Because the naturalistic team decision-making environment is highly complex, there is a need to investigate the performance and process effects of variables that characterize such operational environments. We investigated the effects of team structure and two components of workload (time pressure and resource demand) on team performance and communication over time. Results of the study indicated that time pressure significantly degraded performance relative to resource demand and baseline workload conditions. Although teams exposed to resource demand did not exhibit degraded performance, these teams engaged in fewer statements concerning the availability of team resources than did teams in the other two workload conditions. Results regarding performance and communication changes over time indicated that training interventions might be most effective when imposed during the initial stages of a team's development. We discuss the results in the context of implications for complex decision-making teams.
Alternating Task Modules in Isochronal Distributed Training of Complex Tasks
Authors: GOETTL BARRY P. , YADRICK ROBERT M. , CONNOLLY-GOMEZ CATHERINE , REGIAN J. WESLEY , SHEBILSKE WAYNE L.
Published: January 2017

We compared an alternating task modules (ATM) protocol—which alternated sessions on Space Fortress, Phoenix (video-game-like tasks), and algebra word problems—with a massed protocol, which blocked sessions on the tasks. The protocols were isochronal (equal in duration), each entailing one week of training and testing. ATM gave the men and women an advantage in learning and retention on Space Fortress and algebra word problems; it did not change their performance on Phoenix. Arousal, not confidence or motivation, was implicated in the ATM advantage. The practical implication of demonstrating and describing ATM benefits is that real-world training often requires minimal durations. This pragmatic constraint favors ATM over frequently investigated anisochronal schedules, in which spacing practice over long durations is more effective than massing practice in short durations. Evaluations of retention, arousal, motivation, and confidence began the process of testing theories that might be expanded to explain and enhance ATM benefits.
Real-Time Processing for Rotor-Angle and Rotorspeed Signal Estimation in Noisy Environment
Authors: Ho P. T. , Tso S. K.
Published: January 2017

Real-time processing for rotor-angle and rotor-speed signal estimation in noisy environment

The paper discusses the hardware and software designs to improve the precision of transducers for real-time rotor-angle and rotor-speed small-signal measurements under noisy conditions. Advantage is taken of the spare processing power in microprocessor-based digital controllers to achieve design simplicity and economy. The signals are estimated with minimum delay.
Hunting Instability of The Synchronous Motor
Authors: Watson D. B.
Published: January 2017

Hunting instability of the synchronous motor

A simplied analysis of hunting instability of synchronous motors is presented, together with experimental results.
Harmonic Response and Terminal Resonances of High Voltage Transformers
Authors: Qin Jiang , Bodger P. S.
Published: January 2017

Harmonic response and terminal resonances of high voltage transformers

The first terminal resonance of distribution transformers is evaluated to be above a useful harmonic frequency band, whereas a testing transformer exhibits a low order harmonic resonance. A simple formula relating the first terminal resonance of a transformer to its name place is derived.
Lowpass to Bandpass and Bandstop Transformation: Relations of Coefficients and Poles
Authors: Palomera-GarcíA Rogelio
Published: January 2017

Lowpass to bandpass or bandstop transformation: relations of coefficients and poles

This work deals with algebraic formulae that relate coefficients of bandpass (bandstop) functions with those of the prototype lowpass function under frequency transformation, and also the algebraic formulae relating the poles (and zeros) of the original and transformed functions. These formulae are easy to use with programmable calculators. Examples are given.
Linear Modelling of Op-Amps
Authors: Carlosena Alfonso , Martinez Pedro
Published: January 2017

Linear modelling of op-amps

The aim of this paper is to show the importance of using appropriate modelling for the active elements in op-amp based active circuits. It is shown, through the example of a sinusoidal oscillator, how the ideal model is only valid for low frequency operations. A much better approximation can be obtained by using a single pole model.
Analysis and Design of Analogue Electronic Circuits Using DPI Methods—Part 1
Authors: Asamoah F.
Published: January 2017

Analysis and design of analogue electronic circuits using D.P.I. methods—Part 1

A method of calculating voltages and currents in analogue circuits is presented. The procedure shows how the necessary circuit equations may be written by inspection without the use of loop or node analysis. Examples are given to illustrate the method.
Assertive Logic, A Logical Approach or to be High is to be Not Low
Authors: Taschetta Joseph J.
Published: January 2017

Assertive logic, a logical approach

Assertive logic can become a most useful tool by simplifying complex logic circuitry. In assertive logic, all combinational circuitry can be viewed as an AND, OR, or NOT operation and is invaluable when mixing systems of negative and positive logic. This approach has been proven to be a good foundation to understanding logic fundamentals.
An Autonomous Robot Playing the Board Game Checkers
Authors: Zribi M. , Sung E.
Published: January 2017

In this paper, a project completed by a group of second year students during an in-house practical training program is described. The objective of this project is to produce a system in which a robot is capable of autonomously playing the board game, checkers, against a human player.
Velocity of Propagation in Transmission Lines
Authors: Bonatti Ivanil S. , Peres Pedro L. D. , Lopes Amauri
Published: January 2017

This paper discusses the skin effect on lossy transmission lines in the context of undergraduate electrical engineering courses. A new definition for propagation time derived from Parseval's theorem is proposed. In lossless transmission lines the proposed definition produces the conventional results and for lossy lines it matches quite exactly with the time simulation results, as shown by an illustrative example.
Exact Solutions for Rectangular Bidirectional Composites and Sandwich Plates
Authors: Pagano N.J.
Published: January 2017

In a continuing study, three-dimensional elasticity solutions are constructed for rectangular laminates with pinned edges. The lamina tion geometry treated consists of arbitrary numbers of layers which can be isotropic or orthotropic with material symmetry axes parallel to the plate axes. Several specific example problems are solved, in cluding a sandwich plate, and compared to the analogous results in classical laminated plate theory.
Delamination Growth in Composites under Cyclic Loads
Authors: Dahlen Christian , Springer George S.
Published: January 2017

A semi-empirical model was developed for estimating the growth of delaminations inside fiber reinforced organic matrix composites subjected to cyclic loads. At any point on the circumference of the delamination mode I, mode II or mixed mode conditions may exist. The form of the proposed delamination growth model follows Elber's expression for the growth of a mode I crack in an aluminum sheet. By employing dimensional analysis, the parameters were established which are to be included in the model. The expression obtained depends on the material properties (transverse tensile ply strength, transverse tensile ply modulus, longitudinal ply shear strength, critical energy release rates) and on the energy release rate at the location under consideration. Tests were conducted with Fiberite T300/976 and IM7/977-2 graphite epoxy composites under mode I, mode II and mixed mode conditions using double cantilever beam, end notched cantilever beam, and mixed mode bending test coupons subjected to both static and cyclic loads. From these tests, first, the constants needed in the model were determined. Second, data were generated and compared to predictions of the model, and good agreement was found between the measured and predicted delamination growths. Results of the present model were also compared to data reported previously, and the model predictions agreed well with these previous data.
Ultrastructure of Rat Lungs following Exposure to o-Chlorobenzylidene Malononitrile (CS)
Authors: Colgrave H. F. , Creasey J. M.
Published: January 2017

Three groups of 18 rats were exposed respectively to very large doses of o-chlorobenzylidene malononitrile (CS) of 90 000, 60 000 and 30 000 mg min per m3 and then sacrificed at intervals from 15 min to 2 days, after which lungs were examined macroscopically, by electron microscopy and conventional histology.

Distress appeared to be maximal between 18–36 hr after exposure, when a total of 6 deaths occurred; 4 after a dosage of 90 000 mg min per m3 and 2 after a dosage of 60 000 mg min per m3. In animals that died there was severe congestion and areas of alveolar haemorrhage, with some interstitial oedema. Survivors showed less marked pulmonary congestion, haemorrhage and oedema. Electron micrographs revealed changes to the alveolar epithelium and interstitium in the form of accumulation of fluid between the membrane layers and collagen-containing areas of the septum. The presence of fluid was associated with degenerative changes of the epithelium and endothelium leading to rupture or dissolution of the capillary wall, so allowing the extravasation of red blood cells and fluid into the alveolar space.

This study showed that death after exposure to very high concentrations of CS grenade smoke is accompanied by congestion and severe capillary damage giving rise to pulmonary oedema and haemorrhage. Lung appearances of animals which survived the period of maximum distress suggest that the induced damage is transient. Only if the smoke was used in confined spaces or was deployed in wildly unreasonable concentrations, where persons involved were unable to escape, would the conditions of this investigation even begin to be approached.
Survey of Badge Enamelling in Birmingham
Authors: Smith D. L.
Published: January 2017

Lead poisoning amongst badge enamellers was a well-recognized Problem sixty years ago and working conditions have altered little over the years. This survey shows that there is no longer any significant amount of lead absorption occurring amongst enamellers, although some cases of acute absorption have been reported. The results of some lead in air tests are shown indicating, however, that there is still a hazard and the need for continued vigilance is underlined.
Gm and Inv Grouping of Bloodstains
Authors: Khalap S. , Pereira M. , Rand S.
Published: January 2017

This paper reports the detection of Gm(1), Gm(2) and Inv(1) factors in dried bloodstains using an absorption-inhibition method and also discusses some of the problems involved using ‘case’ material. The technique employed is very simple and requires only small quantities of blood.
Early Formation of Adipocere in Temperate Climate
Authors: Simonsen Jørn
Published: January 2017

A case is reported in which marked adipocere formation in the body of an adult person occurred within 22 days of death, undoubtedly as a result of the extraordinarily hot summer of 1975. A short survey of the literature concerning this topic is given. It is pointed out that even in the temperate zone the weather conditions can for some period of time simulate those of the tropical climate and create facilities for very rapid adipocere formation.
The Investigation of Phenobarbitone, Phenytoin and Primidone in the Death of Epileptics
Authors: Bruce A. M. , Smith Hamilton
Published: January 2017

A survey of the levels (and the corresponding dose rates) of phenobarbitone (1.6 mg/100 ml), phenytoin (0.68 mg/100 ml) and primidone (1.1 mg/100 ml) in the blood of epileptic patients is described. These levels are compared with the concentrations found in the post-mortem samples from people, both normal and epileptic, whose deaths involved these drugs. The results show that the death of an epileptic being treated with the above drugs should be investigated carefully before ascribing it to drug overdosage.
Delinquent Girls before the Courts
Authors: May David
Published: January 2017

One hundred and twenty-six delinquent girls are compared with 730 boys drawn from the same population of schoolchildren in terms of the pattern of their delinquency, certain socio-demographic background characteristics and their disposal by the courts. The prevalence, frequency and seriousness of female delinquency is found to be much less than that of the boys. However, in terms of social background and offence behaviour the similarities are more marked than any differences. Sex-related offences form an insignificant part of female delinquency. Courts show a slight tendency to deal more severely with females. Caution in the use of institutional samples for the study of female delinquency is suggested.