Solving multi-target haptic problems in menu interaction

While haptic feedback has been shown to enhance user performance and satisfaction in single target interactions in desktop user interfaces, it is not clear whether this will hold for more realistic, multi-target interactions. Here we present an experimental study of haptically enhanced menus. We evaluate a visual condition, a haptic condition and an adjusted haptic condition designed to support menu interactions. We conclude that thoughtful design can create multi-target haptic augmentations that provide performance benefits

Communicating with feeling

Communication between users in shared editors takes place in a deprived environment - distributed users find it difficult to communicate. While many solutions to the problems this causes have been suggested this paper presents a novel one. It describes one possible use of haptics as a channel for communication between users. User's telepointers are considered as haptic avatars and interactions such as haptically pushing and pulling each other are afforded. The use of homing forces to locate other users is also discussed, as is a proximity sensation based on viscosity. Evaluation of this system is currently underway

Caring, sharing widgets: a toolkit of sensitive widgets

Although most of us communicate using multiple sensory modalities in our lives, and many of our computers are similarly capable of multi-modal interaction, most human-computer interaction is predominantly in the visual mode. This paper describes a toolkit of widgets that are capable of presenting themselves in multiple modalities, but further are capapble of adapting their presentation to suit the contexts and environments in which they are used. This is of increasing importance as the use of mobile devices becomes ubiquitous

Haptic perception of virtual roughness

The texture of a virtual surface can both increase the sense of realism of an object as well as convey information about object identity, type, location, function, and so on. It is crucial therefore that interface designers know the range of textural information available through the haptic modality in virtual environments. The current study involves participants making roughness judgments on pairs of haptic textures experienced through a force-feedback device. The effect of texture frequency on roughness perception is analysed. The potential range and resolution of textural information available through force-feedback interaction are discussed

Putting the feel in ’look and feel‘

Haptic devices are now commercially available and thus touch has become a potentially realistic solution to a variety of interaction design challenges. We report on an investigation of the use of touch as a way of reducing visual overload in the conventional desktop. In a two-phase study, we investigated the use of the PHANToM haptic device as a means of interacting with a conventional graphical user interface. The first experiment compared the effects of four different haptic augmentations on usability in a simple targeting task. The second experiment involved a more ecologically-oriented searching and scrolling task. Results indicated that the haptic effects did not improve users performance in terms of task completion time. However, the number of errors made was significantly reduced. Subjective workload measures showed that participants perceived many aspects of workload as significantly less with haptics. The results are described and the implications for the use of haptics in user interface design are discussed

Tungsten Behavior at High Temperature and High Stress

Re­cent­ly re­port­ed re­sults on the tung­sten life­time/fa­tigue tests under con­di­tions ex­pect­ed in the Neu­tri­no Fac­to­ry tar­get have strength­ened the case of solid tar­get op­tion for a Neu­tri­no Fac­to­ry. This paper gives de­scrip­tion of the de­tailed mea­sure­ments of the tung­sten prop­er­ties at high tem­per­a­ture and high stress. We have per­formed ex­ten­sive set of mea­sure­ments of the sur­face dis­place­ment and ve­loc­i­ty of the tung­sten wires that were stressed by pass­ing a fast, high cur­rent pulse through a thin sam­ple. Ra­di­al and lon­gi­tu­di­nal os­cil­la­tions of the wire were mea­sured by a Laser Doppler Vi­brom­e­ter. The wire was op­er­at­ed at tem­per­a­tures of 300-2500 K by ad­just­ing the pulse rep­e­ti­tion rate. In doing so we have tried to sim­u­late the con­di­tions (high stress and tem­per­a­ture) ex­pect­ed at the Neu­tri­no Fac­to­ry. Most im­por­tant re­sult of this study is an ex­per­i­men­tal con­fir­ma­tion that strength of tung­sten re­mains high at high tem­per­a­ture and high stress. The ex­per­i­men­tal re­sults have been found to agree very well with LS-DY­NA mod­elling re­sults

On extracting sediment transport information from measurements of luminescence in river sediment

Accurately quantifying sediment transport rates in rivers remains an important goal for geomorphologists, hydraulic engineers, and environmental scientists. However, current techniques for measuring long-time scale (102–106 years) transport rates are laborious, and formulae to predict transport are notoriously inaccurate. Here we attempt to estimate sediment transport rates by using luminescence, a property of common sedimentary minerals that is used by the geoscience community for geochronology. This method is advantageous because of the ease of measurement on ubiquitous quartz and feldspar sand. We develop a model from first principles by using conservation of energy and sediment mass to explain the downstream pattern of luminescence in river channel sediment. We show that the model can accurately reproduce the luminescence observed in previously published field measurements from two rivers with very different sediment transport styles. The model demonstrates that the downstream pattern of river sand luminescence should show exponential-like decay in the headwaters which asymptotes to a constant value with further downstream distance. The parameters from the model can then be used to estimate the time-averaged virtual velocity, characteristic transport lengthscale, storage time scale, and floodplain exchange rate of fine sand-sized sediment in a fluvial system. The sediment transport values predicted from the luminescence method show a broader range than those reported in the literature, but the results are nonetheless encouraging and suggest that luminescence demonstrates potential as a sediment transport indicator. However, caution is warranted when applying the model as the complex nature of sediment transport can sometimes invalidate underlying simplifications

Land resource assessment of Northern Belize (NRI Bulletin 43, Volume 1 of 2)

The land resource assessment was undertaken from July 1989 to June 1990 by the Natural Resources Institute (NRI) of the Overseas Development Administration (ODA), assisted by Mr. A. C. S. Wright, and Dr. M. Holder of Central Farm. The main object of the survey was to produce an updated land suitability assessment of Orange Walk, Corozal, Belize and Cayo districts which had not already been surveyed by Jenkin et al. (1976) and King et al. (1989). In addition, this survey would provide a land suitability assessment for the Belize Valley based on the soil mapping of )en kin et al. Thus, together with the land resource assessments of Toledo and Stann Creek districts (King et al., 1986, 1989 respectively), a land suitability assessment for the whole of Belize is now available