A complete closed-circuit television system

Describes an attempt to improve reading and writing capability of children with severely impaired vision, using a Closed-Circuit Television System, under the supervision of members of clinical staff of the Jerusalem Centre for Counseling and Vision Rehabilitation of Children, and an orientation & mobility instructor.

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Image Enhancement, Micrograph Screening, and Teaching Principles of Contrast with a High Resolution Closed Circuit Television System

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078055 ◽

1977 ◽

Vol 35 ◽

pp. 86-87

Author(s):

Arthur L. Cohen ◽

R.G.E. Steever

Keyword(s):

High Resolution ◽

Light Intensity ◽

Image Enhancement ◽

Closed Circuit ◽

Image Size ◽

Television System ◽

Maximum Information ◽

Closed Circuit Television ◽

Cooling Fan ◽

Teaching Principles

For several years we have been using a closed circuit television system consisting of a high resolution camera (1000 lines), monitor, mount, incident lighting for prints, a light box for negatives with cooling fan and silicon controlled rectifier (SCR) for controlling light intensity. This assembly (Fig. 1) has the following controls: spatial inversion (right-left, top-bottom), image inversion (negative-positive), image height and width, brightness, and contrast. Other image controls (gain, target, pedestal) are infrequently needed. Contrast and tonal range may be widely varied; negatives may be viewed as positives, distortion (as in scanning microscopy) may be corrected, and image size may be adjusted.The system is useful for: (1) Screening negatives for suitability of print ing by displaying them as positives (i.e. simulated prints) thus obtaining an idea of the degree of contrast desired. (2) Extracting the maximum information from a negative.

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Measurement of LEED intensities with a modified closed-circuit television system

Journal of Physics E Scientific Instruments ◽

10.1088/0022-3735/13/3/014 ◽

1980 ◽

Vol 13 (3) ◽

pp. 298-301 ◽

Cited By ~ 10

Author(s):

H Leonhard ◽

A Gutmann ◽

K Hayek

Keyword(s):

Closed Circuit ◽

Television System ◽

Closed Circuit Television

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Cooperative versus Conflictive Problem Solving in Three Telecommunication Modes

Perceptual and Motor Skills ◽

10.2466/pms.1976.42.3.879 ◽

1976 ◽

Vol 42 (3) ◽

pp. 879-917 ◽

Cited By ~ 45

Author(s):

Gerald D. Weeks ◽

Alphonse Chapanis

Keyword(s):

Problem Solving ◽

Closed Circuit ◽

Problem Solution ◽

Visual Channel ◽

Television System ◽

Unique Problem ◽

Closed Circuit Television ◽

Team Members ◽

Face To Face ◽

Class Scheduling

48 two-person teams communicated through channels simulating various modes of telecommunication, teletypewriter, telephone, and closed-circuit television, and, as a control, face-to-face conversation. Each team was required to solve one of four problems. Two cooperative problems, a class scheduling and a geographic orientation problem, required the mutual exchange of factual information to reach the unique problem solution. Two conflictive problems, an issue ranking and a budget negotiation problem, were formulated to engender contention between the two team members. Performance was assessed on three classes of dependent measures: time to solution, behavioral measures of activity, and measures of verbal productivity. Additionally, the protocols and outcomes of the conflictive problem-solving sessions were examined to arrive at a measure of the degree of persuasion exhibited by the two communicators. For both kinds of problem solving, there was a sharp dichotomy in performance, on all three classes of dependent variable, between the teletypewriter mode and the other three modes all of which had a voice channel. Solutions to all problems in the voice modes were much faster but at the same time far more verbose than those in the teletypewriter mode. The addition of a visual channel to a voice mode does not appreciably decrease solution times, nor does it matter whether the visual channel is “live,” that is, face-to-face, or mediated by a closed-circuit television system. For the most part, mode effects were robust and held for all problems. The characteristics of the several modes of communication were largely independent of the kind of task assigned to the teams of subjects.

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