Character Height Research Articles

A kinematic model for the structure of lee‐side deposits

ABSTRACTA kinematic model for the structure of the lee‐side deposit of a dune‐like bedform, Gilbert‐type delta, or similar step is developed, based on the assumptions that initial deposition is entirely by grainfall, that the rate of deposition decreases as a power function of distance downflow from the brink of the slipface, and that the resulting steepening of the slipface is periodically interrupted by avalanching. The parameters used in the model are: (1) the deposition rate at a given distance from the brink, (2) the exponent in the equation relating the deposition rate to distance from the brink, (3) the bedform migration rate, (4) the bedform height, (5) the avalanche speed, (6) the angle of initial yield, and (7) the residual angle after avalanching. From these parameters can be calculated structural characteristics such as the proportions of bottomset and foreset deposits, the proportions of avalanche and grainfall deposits in the foreset deposit, and the spacing of avalanche‐grainfall couplets.The model correctly predicts the trends of changing avalanche activity and changing structural character with changes in flow character, grain size, and bedform height in both air and water. Moreover, the model correctly predicts certain consistent structural differences between aeolian and subaqueous lee‐side deposits. Quantitative evaluation of the model requires more accurate data on the values of the input parameters than are presently available.

Defect groups and character heights in blocks of solvable groups. II

Defect groups and character heights in blocks of solvable groups. II

An Algorithmic Interpretation of the GKS TEXT Primitive

The specification of text output is one of the most complex parts of the GKS standard [1]. The text “geometry” is determined by a wide variety of factors: some, such as character height, are specified directly by the user; others, such as the aspect ratio of a character in a given font, are characteristic of a particular implementation. The GKS document gives a detailed, but informal, description of the way in which these various factors combine to determine the text size and position. The purpose of this paper is to put forward a more formal description of the GKS text geometry: an algorithm is presented that calculates the size and positions of individual character bodies for any text string, under any setting of text attributes, together with the text extent rectangle and concatenation point; a realization of the algorithm as a FORTRAN 77 subroutine is also given. It is hoped that the algorithm will help implementos to interpret the GKS standard more easily.

Defect groups and character heights in blocks of solvable groups

Defect groups and character heights in blocks of solvable groups

An LED numeric display for the aircraft cockpit

This paper describes the construction and performance of an LED numeric display designed specifically for aircraft cockpit applications. The display, using yellow or green LED chips, is a 4-character 7-bar numeric with 4-mm character height mounted in a hermetically sealed package to meet full military device specifications. Legibility studies are reported for this display in ambient illuminations up to 100 000 lux, using different, commercially available contrast-enhancement filters. The results show that the display is completely legible in the highest illumination for a relatively modest power consumption.

On the Heights of Group Characters

For a finite

On the heights of group characters

For a finite p-soluble group G we derive a bound on the heights of the irreducible complex characters of G lying in a p-block B. This bound depends on the prime p and the exponent d of a defect group of B. We show by examples that this bound is of the right order of magnitude.

McKay numbers and heights of characters.

McKay numbers and heights of characters.

Effect of Molybdenum on Cauliflower (Brassica oleracea L. Var Botrytis) in Sand Nutrient Culture

SUMMARYOne ppm molybdenum produced the greatest height, fresh and dry weight per plant; number, fresh and dry weight of leaves; diameter, length, fresh and dry weight of stem; length, fresh and dry weight of roots; yield and yield-attributing characters (height, diameter, fresh and dry weight of curd), and N content of component parts of cauliflower plants (curd, leaf, stem and root). The lowest values for these characters were obtained in the control (nil Mo). Reducing and non-reducing sugars and vitamin C (ascorbic acid) were favourably enhanced (0·5 ppm Mo). The lowest values for sugars and ascorbic acid were observed under 1·0 ppm and nil Mo respectively. The quadratic response curve was drawn in terms of fresh weight of curd and rates of molybdenum application.

Effect of Ambient Illumination on Legibility of Displays of Liquid-Crystals and Light-Emitting Diodes

Two liquid-crystal (LC) and three light-emitting diode (LED) electronic digital displays were evaluated at 1.5, 15, and 45 fc on the display using five criteria: 1) recognition time of single digits, 2) no-error viewing distance, 3) preferred viewing distance, 4) preferred illumination, and 5) subject vote. Recognition time (at a constant viewing angle of 31 min. of arc for the display character height) of the two seven-segment LED displays did not change significantly in the selected range of illumination. For the hexadecimal LED display, recognition time increased significantly from 1.5 to 15 and 45 fc. Recognition time of the reflective LC display decreased significantly from 1.5 to 15 and 45 fc. For the transmissive LC display, recognition time increased significantly from 15 to 45 fc. The no-error viewing distance of the .77″ LED display decreased significantly from 1.5 and 15 to 45 fc but increased significantly from 1.5 to 15 and 45 fc for the reflective LC display. No-error and preferred viewing distances were predicted with multiple regression equations; using just display character height and stroke width/ height gave a multiple R = .91 for no-error viewing distance. The character height viewing angle obtained for no-error viewing distance was 5 min. of arc, but was 17 for preferred viewing distance. Mean preferred illumination was 62 fc for the reflective LC display, 27 for the transmissive LC display, 21 for the .27″, seven-segment LED display, 18 for the .77″, seven-segment LED display, and 10 for the .27″, hexadecimal LED; any difference greater than 9 fc was significant. Preference for the liquid-crystal displays increased at the expense of the light-emitting diode displays as ambient illumination increased from 1.5 to 45 fc.

Character Legibility and Digital Facsimile Resolution

Character legibility was measured as a function of facsimile device parameters (pitch and sampling distance, and scan orientation) and of source document parameters (character height and case). The results indicate (I) very slight average difference in legibility (less than 1%) due to scan direction; (2) a more substantial difference (about 9%) between upper and lower case; and (3) legibility directly proportional to pitch and sampling distances, and to character height. For individual characters in standard typescript or similar material, 97.5% legibility apparently requires resolution on the order of 110 × 110 elements to the inch (scanning aperture nine mils square). Two secondary comparisons established the fact that individual character legibility (a) remained virtually unchanged when continuous scanning (one-mil resolution) was substituted for the best (five-mil) sampling distance, and (b) varied less than 2% when extra test documents were generated to check the repeatability of the experiment.