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T J Doll

Publications and source records attributed to T J Doll.

5 recordsLinked to original sources
PubMed2001

Identification of cervical neoplasia using a simulation of human vision.

OBJECTIVE: To determine whether a computer simulation of human vision could detect and discriminate cervical cancer precursors and cancer from normal epithelium. METHODS: The Georgia Tech Vision (GTV) system was trained to recognize normal and abnormal cervical features. GTV then assessed a new series of images to determine whether it could detect and diagnose cervical neoplasia without any a priori information about the images. RESULTS: After training on one set and testing on another set of images, GTV demonstrated 100% sensitivity and 98% specificity to detect cervical intraepithelial neoplasia 3 (CIN3). GTV also had 88% sensitivity and 93% specificity to detect cervical cancer following training on one set and testing on another set of digitized cervical colposcopic images. CONCLUSION: This study demonstrated that GTV can detect CIN3 and cancer from digitized cervical colposcopic images. Furthermore, GTV could discriminate cervical cancer precursors and cancer from normal cervical epithelium, including immature metaplasia.

Journal Article↗
PubMed1992

Masking in three-dimensional auditory displays.

The extent to which simultaneous inputs in a three-dimensional (3D) auditory display mask one another was studied in a simulated sonar task. The minimum signal-to-noise ratio (SNR) required to detect an amplitude-modulated 500-Hz tone in a background of broadband noise was measured using a loudspeaker array in a free field. Three aspects of the 3D array were varied: angular separation of the sources, degree of correlation of the background noises, and listener head movement. Masking was substantially reduced when the sources were uncorrelated. The SNR needed for detection decreased with source separation, and the rate of decrease was significantly greater with uncorrelated sources than with partially or fully correlated sources. Head movement had no effect on the SNR required for detection. Implications for the design and application of 3D auditory displays are discussed.

Adolescent↗
PubMed1989

Enhanced detection with bimodal sonar displays.

Signal-to-noise ratios (SNRs) required to detect narrow-band signals in white noise were compared for bimodal and single-modality sonar displays at two levels of signal uncertainty and two degrees of spatial compatibility between the auditory and visual displays. In bimodal test conditions the auditory and visual signals were equated in detectability for each subject. An adaptive, two-alternative, forced-choice procedure was used to maintain a constant percentage of correct responses. The decrement in performance with increased signal uncertainty was significantly greater for visual than for auditory displays, suggesting that auditory displays offer advantages for real-world sonar operations. Bimodal displays produced a reliable advantage in SNR required for detection over single-modality displays. Increased compatibility between the visual and auditory displays did not increase the advantage of bimodal presentation, nor did increased signal uncertainty. It was concluded that bimodal displays enhance operators' perceptual sensitivity. The magnitude of the enhancement was consistent with optimal integration of information in the two modalities.

Adult↗
PubMed1986

Auditory signals in military aircraft: ergonomics principles versus practice.

The complete ensembles of auditory signals in selected USAF aircraft (the F-4D, F-15, two models of the F-16, the C-5, and the C-141) are described and evaluated. Human factors research related to the design of speech and non-speech auditory signals is reviewed. Major findings are: that auditory signals are not well standardised among the aircraft, even between those with similar combat roles; that a relatively large number of non-speech auditory signals are used, which may make it difficult for the aircrew to recall the meanings of all the signals; that some non-speech signals are sufficiently similar that they may be confused, particularly in high workload and stressful conditions; and that the criticality of the warnings is not reliably indicated by any characteristic of the signals. Four problem areas requiring further research are discussed: reduction of signal loudness, enhancement of the distinctiveness and masking resistance of non-speech signals, effects of concurrent warning signals on aircrew performance, and additional uses of auditory information.

Journal Article↗