Letter Heights Research Articles

Parallel-mounted On-premise Letter Height and Sign Size

Research and common sense attest to the fact that on-premise projecting signs are more detectable and are readable further away and at smaller sizes than wall-mounted signs. The objective of the current study was to conduct a small-scale field validation of earlier research on minimum letter heights for wall signs and to provide associated minimum square footage for these signs. Eight wall signs that varied in letter height and lateral offset were identified for evaluation on two roadways that varied in posted speed limit and cross-section in Nags Head, North Carolina. Using an empirical procedure involving driving and walking toward the signs, the legibility distances for these signs were evaluated and were found to compare favorably to past research that employed an analytical approach. An equation to determine sign size in square feet was also developed. Future research to further these findings is outlined.

Small Text on Product Labels Poses a Special Challenge for Emerging Presbyopes.

Approximately 10% of the lowercase text on nonprescription drug labels is smaller than the 1 mm required by the Food and Drug Administration. The small size, combined with the progressive decline in accommodative amplitude and gain, poses a reading challenge for middle-aged emerging presbyopes. The purpose of this study was to evaluate the impact of progressing presbyopia and near adds on the ability of middle-aged patients to read small text routinely encountered on product labels. Geometrical optics was used to determine the impact of changing viewing distance, accommodation, and pupil size on retinal blur size. We photographed 261 consumer product labels in grocery, personal care, and nonprescription (over-the-counter) drug categories and used character recognition software to identify and size 255,298 printed letters. We computed the impact of viewing distance on the ratio of blur to letter detail and used published blur ratios of ≤4 and ≤2 to identify the conditions that allowed for letter recognition and proficient reading, respectively. Median/mode lowercase letter heights (in millimeters) were 1.39/1.16, 1.29/1.15, and 1.18/1.01, respectively, for groceries, personal care, and over-the-counter drug categories. Despite the increased angular subtense of approaching letters, blur ratios generally increased with reduced viewing distance because of increased defocus. Increased viewing distance decreased blur, but small (e.g., 1 mm) letters became too small to read proficiently (angular size <10 arcminutes) for distances beyond 37 cm. With larger pupils, blur ratios were too large to support proficient reading when accommodative amplitude dropped to ≤3 diopters. An add power sufficient to bring the far point closer than 37 cm was required to proficiently read small text. Product labels, especially nonprescription drug packages, typically use fonts that are too small to be read proficiently by unaided emmetropes with emerging presbyopia. This problem can be ameliorated by correction of presbyopia at an earlier age and with higher add powers.

Layout measures for writer identification in mediaeval documents

Paleography aims to study ancient documents, with the identification of the writer hands being one of the most important problems. Over the years, experienced palaeographers have devised many methodological approaches to writer identification. These methodologies are based on traditional palaeographical tools to measure quantities such as letter heights and widths, distances between characters and angles of inclination. In this paper we present a novel approach in which basic layout measures are used for identifying the writers of a single medieval Latin book. The proposed measures take into account some general properties related to the organization of the whole page (such as margins, distance between columns, etc.), and some specific properties characterizing the ability of the writer to exploit the available space and to distribute the text in each row. The experimental results, performed on a set of digital images from a Latin copy of the whole Bible of the XII century, confirmed the effectiveness of the proposed method. We have also tested our approach on another bible obtaining similar results.

Skylign: a tool for creating informative, interactive logos representing sequence alignments and profile hidden Markov models

BackgroundLogos are commonly used in molecular biology to provide a compact graphical representation of the conservation pattern of a set of sequences. They render the information contained in sequence alignments or profile hidden Markov models by drawing a stack of letters for each position, where the height of the stack corresponds to the conservation at that position, and the height of each letter within a stack depends on the frequency of that letter at that position.ResultsWe present a new tool and web server, called Skylign, which provides a unified framework for creating logos for both sequence alignments and profile hidden Markov models. In addition to static image files, Skylign creates a novel interactive logo plot for inclusion in web pages. These interactive logos enable scrolling, zooming, and inspection of underlying values. Skylign can avoid sampling bias in sequence alignments by down-weighting redundant sequences and by combining observed counts with informed priors. It also simplifies the representation of gap parameters, and can optionally scale letter heights based on alternate calculations of the conservation of a position.ConclusionSkylign is available as a website, a scriptable web service with a RESTful interface, and as a software package for download. Skylign’s interactive logos are easily incorporated into a web page with just a few lines of HTML markup. Skylign may be found at http://skylign.org.

The Variability Measurement of Shape Independent Features to Establish a New Method to Differentiate Genuine Signatures from Simulated Ones

A preliminary step to the examination of signatures is the objective assessment of the variability range that is peculiar to the writer; in document examination it is quite rare to come across standardized procedures allowing an effective discrimination between genuine and simulated signatures. This study took into consideration 104 questioned signatures (coming from 20 real and Judge-ruled cases) that were inspected to evaluate non-shape-related indicators in their ability to assess correctly genuineness or simulation; the research particularly focused on the evaluation of letter heights - with special reference to the positions of the individual letters within the signature - and on the subsequent height ratios between extenders (upper and lower) and the other small letters. The combination of the information gained from the statistical survey, assisted by calculation of confidence intervals, of these height indicators with the observation within the signature of the spots where between-letter pen lifts occur led to an effective discriminating method for medium/long signatures. Data processing also yielded useful indications on the letters that most frequently trigger off height errors in forgery and provided other interesting results, such as the positions within the signature where simulators most frequently fail.

Effects of Font Size and Reflective Glare on Text-Based Task Performance and Postural Change Behavior of Presbyopic and Nonpresbyopic Computer Users

Nineteen young (18-35 year-old) and seven older presbyopic (55-65 year-old, wearing bifocal or progressive glasses) subjects with the same average visual acuity at near distance participated in this full-factorial, repeated measures study with two trial factors: font size (capital letter heights of 1.78, 2.23, and 3.56 mm) and reflective glare. The monitor location was fixed, but subjects were allowed to move their bodies and the chair while performing visually demanding tasks. The productivity improved up to 30% when using a large font size (average visual angle 23.4 arcmin) compared to a smaller font size (14.2 or 16.4 arcmin, p &lt; .0001). The relative contributions of torso flexion (78%), head forward (3%), and chair reposition (4%) to changes in the viewing distance remained constant across font size conditions. Reflective glare had no effect on productivity measures but led to reduction of viewing distance ( p &lt; .0001). There were no significant differences between the two age groups.

Schottky Barrier Height of Nickel Silicide Contacts Formed on $\hbox{Si}_{1 - x}\hbox{C}_{x}$ Epitaxial Layers

Embedded Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1 -</sub> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> C <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> source/drain junctions are currently considered to achieve electron mobility enhancement in nMOSFETs by inducing uniaxial tensile strain in the channel region. To utilize the mobility advantage of this technology, it is imperative to form low-resistivity contacts to Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1 -</sub> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> C <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> alloys. In this letter, the electron and hole barrier heights at the NiSi/Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1 -</sub> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> C <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> interface were measured up to a carbon concentration of 1.2%. The results indicate that the NiSi Fermi level moves away from the valence-band edge with increasing carbon concentration such that the hole barrier height increases by 68 meV in spite of the upward movement of the valence band. Within the same carbon concentration range, the electron barrier height decreases by as much as 170 meV, which is significant considering the exponential dependence of contact resistivity on barrier height.

Legibility Distances of Smaller Letters in Changeable Message Signs with Light-Emitting Diodes

This paper presents the results of a legibility study of 9-in. and 10.6-in. letters on changeable message signs (CMSs) with light-emitting diodes. The study, conducted in Dallas, Texas, consisted of 60 subjects, demo-graphically balanced with respect to age, gender, and education. The subjects drove a test vehicle as they approached CMSs with one of the above letter heights. Study administrators recorded the distance from the sign at which the participant could correctly read a three-letter word. Data were recorded for three trials on each of the letter heights for each participant. Data were collected during daylight (sun overhead) and nighttime conditions. The 85th percentile legibility distance for the 9-in. letter height was 228 ft for daytime conditions and 114 ft for nighttime conditions. For the 10.6-in. letter height, the 85th percentile legibility distances were 324 ft for daytime conditions and 203 ft for nighttime conditions, respectively. The 85th percentile legibility distances for each letter height were used to estimate available viewing times under various approach speeds. These available viewing times dictate the units of information that can be presented on a CMS of a particular letter size.

Legibility Distances of Smaller Letters in Changeable Message Signs with Light-Emitting Diodes

This paper presents the results of a legibility study of 9-in. and 10.6-in. letters on changeable message signs (CMSs) with light-emitting diodes. The study, conducted in Dallas, Texas, consisted of 60 subjects, demographically balanced with respect to age, gender, and education. The subjects drove a test vehicle as they approached CMSs with one of the above letter heights. Study administrators recorded the distance from the sign at which the participant could correctly read a three-letter word. Data were recorded for three trials on each of the letter heights for each participant. Data were collected during daylight (sun overhead) and nighttime conditions. The 85th percentile legibility distance for the 9-in. letter height was 228 ft for daytime conditions and 114 ft for nighttime conditions. For the 10.6-in. letter height, the 85th percentile legibility distances were 324 ft for daytime conditions and 203 ft for nighttime conditions, respectively. The 85th percentile legibility distances for each letter height were used to estimate available viewing times under various approach speeds. These available viewing times dictate the units of information that can be presented on a CMS of a particular letter size.

Evaluation of tactile fonts for use by a visually impaired elderly population

Purpose: To study the learning and reading of tactile fonts by seniors. Design: One hundred blindfolded subjects age 65 years and older were taught and studied one of three tactile fonts: a new font named ELIA, the standard Braille font, or a raised Roman font. Methods: ELIA and Roman texts were presented at letter heights of 1.0 cm, 1.1 cm, 1.2 cm, and 1.3 cm, while Braille texts were presented at the standard size (0.7 cm). Training lasted for 30 hours. Test stimuli were presented as single letters in random order or as words in sentences. Results: It was found that ELIA was read with greater speed and letter recognition accuracy than the Roman font and that both the ELIA and Roman fonts were read with greater speed and accuracy than the Braille font. Implications: Most seniors are capable of reading tactile fonts, which can be utilized to achieve greater independence.

Interaction of screen distances, screen letter heights and source document distances

An experiment was conducted to investigate the main and interaction effects of screen distances (600 mm and 900 mm), screen letter heights (for visual angles of 16, 20, and 30 minutes of arc), and source document distances (same as the screen distance and closer than the screen distance) on visual performance and subjective preference in text proofreading tasks. Thirty subjects in different age groups participated in the experiment. The experimental results revealed that the subjects' performance improved from the letter height of 16 minutes of arc to the letter height of 20 minutes of arc for the 600 mm screen distance, but from 20 minutes of arc to 16 minutes of arc for the 900 mm screen distance. The subjects generally preferred a screen distance slightly higher than 600 mm, a letter height at the 22 minutes of arc, and a small difference between the visual angle of screen letters and the visual angle of source letters.

Measurement of Handwriting Factors

Alston (1988) suggests quantification of handwritings for educational purposes is necessary to assess students' progress. Electronic digital callipers aided by a three-power magnifier lamp give accurate metric measurements so that interrater reliab&ty is greater than 95%. following 17 factors in handwriting are routinely and accurately measured: at which angle lines move across the page, slant of letters, width of letters, between words, between lines, heights of letter aJ heights of letter heights of lower loop of letter g, heights of letter 'IfJ'' widths of letter t crossing, heights of letter t crossing, left margins, right margins, total margins for same paragraph, difference between margins, pressure of writing on the page, and quality of writing on the page. This measurement guide has been used to study the handwritings of college students and their- families. We have reported Pearson product-moment correlations of parentlchild pairings that suggest an inherited influence for space between words (Peeples & Morris, 1985). Subsequent work suggests three more of these measured factors are both inherited and highly correlated among themselves (height of the t-crossing, height of the letter f and height of the letter a). following two paragraphs can be used in collecting uniform samples from large groups of subjects. This sample of my handwriting must have within it all the twenty-six bterr of the English alphabet. Therefore, it is necessary to include something silly, such as The quick red fox jumps over the lozy brown dog. Also, because nrtmbers may be useful in this research program, I will write 1, 2, 3, 4, 5, 6, 7, 8, 9, and 0. If I had my way, I would travel to the /ar ends of the earth. Preferably, I would take the proverbial Slow boat to China and see the sights of all parts of the world at my leisure. If I can't see the whole wide world, I want to begin in Italy before Spring.

Scientific Poster Lettering and Display

Abstract ASHS specifies that minimum heights for poster lettering be 25 mm for the titles, authors, and institutions and 12.5 mm for everything else (ASHS, 1988). A survey of 167 posters in Poster Session 1 at the 1988 Annual Meeting indicated that these required minimum lettering sizes are usually not met (Table 1). One reason why these minimums are rarely met is that the minimum heights are unrealistic. The minimum heights were established for 2.4 × 1.2-m posters and not reduced when poster area was halved to 1.2 by 1.2 m. The 1:1 ratio between title and author/institution letter heights is not proportional because title lettering is nearly always taller than author/institution lettering. For example, HortScience titles are 5 mm tall with author/institution lettering 2.5 mm high. Thus, the smaller lettering for authors/institutions compared to titles on ASHS posters is understandable.

Letter Size and Legibility

The legibility of displayed letters depends upon their size, or more accurately, their subtended visual angle at any viewing distance. Current design standards recommend letter heights in the range from 0.003 to 0.007 rad (10 to 24 mill of arc) for good viewing conditions, with 0.0015 rad (5 min) considered a lower limit based on normal visual acuity. A field study involving some 2000 measures for over 300 printed displays found a mean letter height of 0.0019 rad (7 min) at the limit of legibility, with over 90% legibility at 0.003 rad and virtually 100% at 0.007 radians.

Preparation of Lantern-Slide Copy

The major defects in faulty lantern slides are usually: (1) the scale of lettering on the original copy is too small; and (2) the lines, letters, and figures are overcrowded on the original copy. These defects result in the projected image being illegible on the screen. As mechanical or photographic defects can be eliminated by reliable lantern-slide makers they are not discussed here. A standardized procedure is presented for use in drafting maps, charts, tables, et cetera, for lantern-slide presentation. This procedure consists of a simple formula and a series of charts to illustrate the minimum letter and figure heights that should be used on the original lantern-slide material. The formula is based on the following three factors that control the legibility of lantern slides: (1) maximum size of lecture room, or maximum audience distance, (2) size or width of original lantern-slide copy, and (3) size or width of screen on which lantern slide is to be projected. Illustrations of geological maps, cross sections, and electric logs have been prepared following the recommended formula. The dimensions set forth here for original lantern-slide copy represent a figure and letter size appreciably larger than the minimum size employed for routine drafting work. This discussion of dimensions also supports the general conclusion that most original copy must be redrafted for lantern-slide reproduction in order to provide larger figure and letter sizes, if good results are to be secured.