Layout simulation for keyboards

Abstract

The oldest element on any personal computer is the keyboard: its design (the spatial position of the keys in relation to each other) and its layout (the assignment of letters, numerals, and other signs to keys). The are exactly the same as on the first typewriters of over 100 years ago or are they? The layout has been the topic of improvement for more than 70 years but no real change has materialized. We contribute to the efforts of layout reformers in Pollatschek et al. (1986).

In this paper, we introduce a simple simulation tool for evaluating layout, while in an accompanying communication we advise on a cheap and effective way to convert any given layout to any desired one.     

Random Graphs In A Neural Computation Model

We examine in this work the following graph theory problem that arises in neural computations that involve the learning of boolean expressions by studying the asymptotic connectivity properties of $G_{n\comma 1/\lpar kn\rpar ^{1/2}}$ random graphs, where k is a fixed positive integer. For an undirected graph $G = \lpar V\comma \; E\rpar $ let $N\lpar X\comma \; Y\rpar = \lcub v \in V - \lpar X \cup Y\rpar \!\mid$ $ \exists x \in X\ \hbox{with}\ \lpar v\comma \; x\rpar \in E\rcub $ . For fixed k construct an undirected graph $G = \lpar V\comma \; E\rpar $ such that for all disjoint sets $A\comma \; B \subseteq V$ such that $\vert A \vert = \vert B \vert = k$ , and $C = N\lpar A\comma \; B\rpar \cap N\lpar B\comma \; A\rpar $ , set C is such that $\vert C \vert$ is either exactly k or as close to k as possible. Asymptotic results for large values of k are also presented.     

The customizable keyboard

Abstract

The need for deviations from the widely accepted QWERTY keyboard layout of usual office typewriters or workstations has been discussed in our twin paper (Gilad et al. 1986). In this paper we examine a related issue: How to customize any keyboard to a given application, cheaply and effectively. We here discuss this issue and establish why such customization is necessary and how modern technology and keyboard design solve half the problem.     

Layout simulation for keyboards

The oldest element on any personal computer is the keyboard: its design (the spatial position of the keys in relation to each other) and its layout (the assignment of letters, numerals, and other signs to keys). The are exactly the same as on the first typewriters of over 100 years ago or are they? The layout has been the topic of improvement for more than 70 years but no real change has materialized. We contribute to the efforts of layout reformers in Pollatschek et al. (1986).

In this paper, we introduce a simple simulation tool for evaluating layout, while in an accompanying communication we advise on a cheap and effective way to convert any given layout to any desired one.     

A quantitative assessment of changes in work activities resulting from computer-assisted design

Abstract

In an effort to understand how computer-assisted design (CAD) can be optimized in an organizational setting, perceptions and attitudes of CAD users about their jobs and workplace are compared with those of non-users. Results indicate that the implementation of CAD may not result in the expected benefits if CAD is not appropriately managed. Job unpredictability, job autonomy, and job interdependence are three areas in particular needing management attention if CAD benefits are to be achieved.     

A quantitative assessment of changes in work activities resulting from computer-assisted design

In an effort to understand how computer-assisted design (CAD) can be optimized in an organizational setting, perceptions and attitudes of CAD users about their jobs and workplace are compared with those of non-users. Results indicate that the implementation of CAD may not result in the expected benefits if CAD is not appropriately managed. Job unpredictability, job autonomy, and job interdependence are three areas in particular needing management attention if CAD benefits are to be achieved.     

The customizable keyboard

The need for deviations from the widely accepted QWERTY keyboard layout of usual office typewriters or workstations has been discussed in our twin paper (Gilad et al. 1986). In this paper we examine a related issue: How to customize any keyboard to a given application, cheaply and effectively. We here discuss this issue and establish why such customization is necessary and how modern technology and keyboard design solve half the problem.     

Instability of non-linear time-varying systems: combined conditions on the derivatives

An (L₂-)stability criterion is derived for non-linear time-varying (NLTV) systems with a separable gain (k(t).f(.)) in the feedback-path, where f(.) is monotone, using a simple R-L multiplier (s + β)/(s + α)(α > β) and involving the first and second derivatives of k(t). The criterion seems to be very much relaxed for systems with a slowly time-varying gain k(t).     

Educational aspects of television subtitling in deaf education†

The increasing availability of microcomputers and video technology in schools is opening the way towards local ‘do-it-yourself’ video subtitling facilities. Over the last five years, many teachers of deaf children have begun to recognize the educational benefits of subtitled television, but the means for effective, yet low-cost, subtitling did not exist. Building on our earlier experience with broadcast-teletext subtitling we initiated work, funded by the Mountbatten Memorial Trust, to fulfil this need.

To gauge the extent of interest in local subtitling, and to gather design data for the project, a national survey of the uses of television and related media in the education of deaf children was undertaken. Existing methods of adapting educational broadcasts to provide access for deaf children were of particular interest in the survey.

As a result of our work, a prototype low-cost subtitling system has been developed, based on video and computer equipment already widely available in schools. Technical details of the system are described in the companion paper. A programme of technical evaluation of the equipment in schools for the deaf and units for hearing impaired children (attached to mainstream and special schools) has just been concluded. A feature of this work has been the close collaboration with teachers of the deaf. As a result of these trials, a commercial system is being produced and guidelines for effective educational subtitling are starting to emerge.     

Internet vs. paper and pencil administration of questionnaires commonly used in panic/agoraphobia research

The aim of this study was to investigate the psychometric properties of Internet administered questionnaires used in panic research. Included were 494 people who had registered for an Internet-based treatment program for panic disorder (PD). Participants were randomly assigned to fill in the questionnaires either on the Internet or the paper-and-pencil versions, and then to fill in the same questionnaires again the next day using the other format. The questionnaires were the body sensations questionnaire [BSQ; Chambless, D. L., Caputo, G. C., Bright, P., & Gallagher, R. (1984). Assessment of fear of fear in agoraphobics: the body sensations questionnaire and the agoraphobic cognitions questionnaire. Journal of Consulting and Clinical Psychology, 52, 1090–1097], agoraphobic cognitions questionnaire [ACQ; Chambless, D. L., Caputo, G. C., Bright, P., & Gallagher, R. (1984). Assessment of fear of fear in agoraphobics: the body sensations questionnaire and the agoraphobic cognitions questionnaire. Journal of Consulting and Clinical Psychology, 52, 1090–1097], mobility inventory [MI; Chambless, D. L., Caputo, G., Jasin, S., Gracely, E. J., & Williams, C. (1985). The mobility inventory for agoraphobia. Behaviour Research and Therapy, 23, 35–44], beck anxiety inventory [BAI; Beck, A. T., Epstein, N., Brown, G., & Steer, R. A. (1988). An inventory for measuring clinical anxiety: psychometric properties. Journal of Consulting and Clinical Psychology, 56, 893–897], beck depression inventory II [Beck, A. T., & Steer, R. A. (1996). Beck Depression Inventory. Manual, Svensk version (Swedish version). Fagernes, Norway: Psykologiförlaget, AB], quality of life inventory [QOLI; Frisch, M. B., Cornell, J., Villanueva, M., & Retzlaff, P. J. (1992). Clinical validation of the quality of life inventory. A measure of life satisfaction for use in treatment planning and outcome assessment. Psychological Assessment, 4, 92–101], and montgomery Åsberg depression rating scale [MADRS; Svanborg, P., & Åsberg, M. (1994). A new self-rating scale for depression and anxiety states based on the comprehensive psychopathological rating scale. ACTA Psychiatrica Scandinavica, 89, 21–28]. Results showed largely equivalent psychometric properties for the two administration formats (Cronbach’s α between 0.79 and 0.95). The results also showed high and significant correlations between the Internet and the paper-and-pencil versions. Analyses of order effects showed an interaction effect for the BSQ and the MI (subscale Accompanied), a main effect was identified for ACQ, MI-Alone, BAI and BDI II. However, in contrast to previous research, the Internet version did not consistently generate higher scores and effect sizes for the differences were generally low. Given the presence of an interaction effect, we recommend that the administration format should be stable in research across measurement points. Finally, the findings suggest that Internet versions of questionnaires used in PD research can be used with confidence.     

Learning to use a word-processing system as a function of training strategy

Three training strategies were evaluated for their effectiveness in teaching naive computer users to use a word-processing system. One hundred and thirty five women ranging in age from 25 years to 70 years participated in the study. Subjects were trained using one of three techniques (instructor, manual, computer( to perform basic word-processing tasks. The effectiveness of the training strategies was assessed by examining performance on basic word-processing tasks such as typing a letter or memo and editing an existing file. Results showed that for all subjects, computer-based training was a less effective teaching method than either instructor- or manual-based training. In general, subjects who were trained using the computer-based method attempted and completed fewer tasks, took longer to perform tasks, and also made more errors. These findings demonstrate the need for directing efforts towards the development of appropriate training methods for computer tasks     

Wrist discomfort levels for combined movements at constant force and repetition rate

Sixteen male subjects each performed a repetitive, downwards, non-prehensile wrist exertion task with the arm pronated, at a rate of 15 times per minute and with a force of 10N?±?1N in 49 combinations of flexion/extension and radial/ulnar deviation to 0%, 18%, 38% and 55% of the Range of Motion (ROM) for 5 min each. The dependent measure was discomfort measured on a 100 mm visual analogue scale and for most of the analyses these were standardized by using the min?-?max procedure of <citeref rid="b20">Gescheider (1988)</citeref>. These Standardised Discomfort Levels (SDLs) were fitted to mathematical equations from which iso-discomfort contours were derived relative to the percentages of flexion/extension and radial/ulnar-deviation ROM used. The lowest standardized discomfort was found for the neutral wrist posture, followed by 18% extension with neutral radial/ulmar deviation. The results reveal interesting features of the processes involved and provide useful avenues for further research.     

Underwater movement times with ongoing visual control

Arm movements made in a water environment take longer to perform than in an air environment due to the drag forces experienced by the arm. Movement times for ballistic underwater movements have been accurately modelled by Hoffmann and Gan (1988 Hoffmann, E.R. and Gan, K-C. 1988. Underwater ballistic movements. Ergonomics, 31(9): 1305–1316. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). The present work models the movement time for movements that require ongoing visual control. In these movements, the ‘distance-covering’ phase is carried out at high speeds and will be affected by the fluid characteristics, while the ‘homing-in’ phase, where speeds are low, is less affected. An experiment is reported that models these effects and which indicates that a ballistic component needs to be added to the standard Fitts model in order to account for the drag forces in the distance-covering phase of the movement.

Practitioner Summary: Many tasks, such as maintenance and salvage work, require work to be done underwater. Times for performing underwater tasks are generally longer than on land. This article is one step in modelling the difference in task times for land and underwater movements.     

Quantitative analysis of temperature effect on SOI piezoresistive pressure sensors

Microsystem Technologies - Quantitative analysis of the temperature effect on piezoresistive pressure sensor response for operation at 200 bar, 200 °C was carried out through...     

Information technology and U.S. policy: Strategic options for the eighties

The 1980's can be expected to experience a profound transformation in information technology and information services. These include:

• •a confluence of diverse technology;
• •multi-industry, multinational and multigovernment R & D participation;
• •productivity increases along a broad front;
• •innovation as a self-generating cycle of new products;
• •an acceleration in the innovation process;
• •an increase in product obsolescence;
• •the migration of cheap intelligence to the shop, home, office and store;
• •the proliferation of information networks - regional, national, international;
• •the erosion of traditional market boundary lines and distinctions.

These developments confer a series of critical strategic options upon the public and the private sector in the United States.If public policy anticipates the future, broadens its portfolio, unleashes creative energy, rewards risk taking and abolishes traditional regulation, then the U.S. information economy will at least possess an opportunity to flourish in the decade of the 80's. If, on the other hand, policy continues its jurisdictional creep, stifles entry, regulates risks and penalizes entrepreneurship, then the U.S. economy risks forfeiting its future on the altar of tradition.     

In situ angular measurements of thermal infrared sea surface emissivity—Validation of models

In this paper, sea surface emissivity (SSE) measurements obtained from thermal infrared radiance data are presented. These measurements were carried out from a fixed oilrig under open sea conditions in the Mediterranean Sea during the WInd and Salinity Experiment 2000 (WISE 2000). The SSE retrieval methodology uses quasi-simultaneous measurements of the radiance coming from the sea surface and the downwelling sky radiance, in addition to the sea surface temperature (SST). The radiometric data were acquired by a CIMEL ELECTRONIQUE CE 312 radiometer, with four channels placed in the 8-14 μm region. The sea temperature was measured with high-precision thermal probes located on oceanographic buoys, which is not exactly equal to the required SST. A study of the skin effect during the radiometric measurements used in this work showed that a constant bulk-skin temperature difference of 0.05±0.06 K was present for wind speeds larger than 5 m/s. Our study is limited to these conditions. Thus, SST used as a reference for SSE retrieval was obtained as the temperature measured by the contact thermometers placed on the buoys at 20-cm depth minus this bulk-skin temperature difference.SSE was obtained under several observation angles and surface wind speed conditions, allowing us to study both the angular and the sea surface roughness dependence. Our results were compared with SSE models, showing the validity of the model of Masuda et al. [Masuda, K., Takashima, T., & Takayama, Y. (1988) Emissivity of pure seawaters for the model sea surface in the infrared window regions. Remote Sensing of Environment, 24, 313-329.] for observation angles up to 50°. For larger angles, the effect of double or multiple reflections on the sea surface produces discrepancies between measured and theoretical SSEs, and more complex models should be used to get accurate SSE values, such as the model of Wu and Smith [Wu, X., & Smith, W.L. (1997). Emissivity of rough sea surface for 8-13 μm: modelling and verification. Applied Optics, 36, 2609-2619.].     

Knowledge in shared memory systems

Summary We study the relation between knowledge and space. That is, we analyze how much shared memory space is needed in order to learn certain kinds of facts. Such results are useful tools for reasoning about shared memory systems. In addition we generalize a known impossibility result, and show that results about how knowledge can be gained and lost in message passing systems also hold for shared memory systems. Michael Merritt received a B.S. degree in Philosophy and in Computer Science from Yale College in 1978, the M.S. and Ph.D. degrees in Information and Computer Science in 1980 and 1983, respectively, from the Georgia Institute of Technology. Since 1983 he has been a member of technical staff at AT & T Bell Laboratories, and has taught as an adjunct or visiting lecturer at Stevens Institute of Technology, Massachusetts Institute of Technology, and Columbia University. In 1989 he was program chair for the ACM Symposium on Principles of Distributed Computing. His research interests include distributed and concurrent computation, both algorithms and formal methods for verifying their correctness, cryptography, and security. He is an editor for Distributed Computing and for Information and Computation, recently co-authored a book on database concurrency control algorithms, and is a member of the ACM and of Computer Professionals for Social Responsibility. Gadi Taubenfeld received the B.A., M.Sc. and Ph.D. degrees in Computer Science from the Technion (Israel Institute of Technology), in 1982, 1984 and 1988, respectively. From 1988 to 1990 he was a research scientist at Yale University. Since 1991 he has been a member of technical staff at AT & T Bell Laboratories. His primary research interests are in concurrent and distributed computing.A preliminary version of this work appeared in the Proceedings of the Tenth Annual ACM Symposium on Principles of Distributed Computing, pages 189–200, Montreal, Canada, August 1991     

Characterization of the Sonar Signals Benchmark

We study the classification of sonar targets first introduced by Gorman & Sejnowski (1988). We discovered that not only the training set and the test set of this benchmark are both linearly separable, although by different hyperplanes, but that the complete set of patterns, training and test patterns together, is also linearly separable. The distances of the patterns to the separating hyperplane determined by learning with the training set alone, and to the one determined by learning the complete data set, are presented.     

A refinement for the Rayleigh radiance computation with variation of the atmospheric pressure

The Rayleigh scattering radiance at the top of the atmosphere (TOA) depends on the surface atmospheric pressure. In processing the Coastal Zone Color Scanner (CZCS) imagery, Gordon et al. (Applied Optics, 27, 862–871, 1988 Gordon, H. R., Brown, J. W. and Evans, R. H. 1988. Exact Rayleigh scattering calculations for use with the Nimbus‐7 Coastal Zone Color Scanner.. Applied Optics, 27: pp. 862–871. [Crossref] , [Google Scholar]) developed a simple formula to account for the Rayleigh radiance changes with the variation of the surface atmospheric pressure. For the atmospheric pressure changes within ±3%, the accuracy of the Gordon et al. (1988 Gordon, H. R., Brown, J. W. and Evans, R. H. 1988. Exact Rayleigh scattering calculations for use with the Nimbus‐7 Coastal Zone Color Scanner.. Applied Optics, 27: pp. 862–871. [Crossref] , [Google Scholar]) formula in computing the Rayleigh radiance is usually within 0.4%, 0.3%, 0.15% and 0.05% for the wavelengths 412, 443, 555 and 865 nm, respectively. This could result in up to ～3% uncertainty in the derived water‐leaving radiance at the blue wavelengths for very clear atmospheres. To improve the performance, a refinement to the Gordon et al. (1988 Gordon, H. R., Brown, J. W. and Evans, R. H. 1988. Exact Rayleigh scattering calculations for use with the Nimbus‐7 Coastal Zone Color Scanner.. Applied Optics, 27: pp. 862–871. [Crossref] , [Google Scholar]) formula is developed based on the radiative transfer simulations. The refined scheme can produce Rayleigh radiance with an uncertainty within 0.1% (often within 0.05%) at the blue, while uncertainty is within 0.05% for the green to near‐infrared wavelengths. The refined algorithm has been implemented in the Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) data processing system. Results from the SeaWiFS data show the improved ocean colour products in the southern oceans where consistently low atmospheric pressures are usually observed. This could also significantly improve the performance of the Rayleigh radiance computations over the high altitude lakes. In addition, with the refined algorithm, the same Rayleigh radiance tables can be possibly used for the various ocean colour satellite sensors in which there are slightly different sensor spectral band characterizations.