Notational Techniques for Accommodating User Intention Shifts

Good user interface designs allow for user intention shifts. The asynchronous nature of direct maniulation interfaces inherently demands consideration of user intention shifts during the performance of a task. Maintaining a focus on the primary function of a task while at the same time accommodating user intention shifts is difficult for interface designers when both these aspects are represented at the same design level. The User Action Notation (UAN), a technique for representing asynchronous interfaces, contains a mechanism for specifying points in a task where user intention shifts may occur. A complementary technique, Task Transition Diagrams (TTDs), is used to specify tasks that users can perform to interrupt their current task. The Task Transition Diagram is a notation that allows a designer to map out the set of tasks and intentions of users without having to be concerned with the minutiae of how a user accomplishes those tasks

Computer Analysis of User Interfaces

Interface evaluation is a necessary phase in the production of quality user interfaces. The usual evaluation techniques involve formal experiments or observation, and can be invasive. One non-invasive method that can be used at user sites is to record all user input and system output to a file. This transcript is then algorithmatically analyzed to determine interface problems. A new technique analyzes these transcripts by searching for maximal repeating patterns (MRPs), on the hypothesis that repeating sequences of user actions indicate interesting user behavior, and therefore may show problems in the interface. The technique was tested by using it to evaluate the human-computer interface of a large and complex image processing system in active use. Results show MRPs useful in detecting specific problems within the interface

Task-Oriented Representation of Asynchronous Interfaces

A simple, task-oriented notation for describing user actions in asynchronous user interfaces is introduced. This User Action Notation (UAN) allows the easy association of actions with feedback and system state changes as part of a set of asynchronous interface design techniques, by avoiding the verbosity and potential vagueness of prose. Use within an actual design and implementation project showed the UAN to be expressive, concise, and highly readable because of its simplicity. The task-and user-oriented techniques are naturally asynchronous and a good match for object-oriented implementation. Levels of abstraction are readily applied to allow definition of primitive tasks for sharing and reusability and to allow hiding of details for chunking. The UAN provides a critical articulation point, bridging the gap between the task viewpoint of the behavioral domain and the event-driven nature of the object-oriented implementational domain. The potential for UAN task description analysis may address some of the difficulties in developing asynchronous interfaces

Mechanically Strong, Thermally Stable, and Electrically Conductive Nanocomposite Structure and Method of Fabricating Same

A nanocomposite structure and method of fabricating same are provided. The nanocomposite structure is a polymer in an extruded shape with carbon nanotubes (CNTs) longitudinally disposed and dispersed in the extruded shape along a dimension thereof. The polymer is characteristically defined as having a viscosity of at least approximately 100,000 poise at a temperature of 200 C

Hypervelocity Impact Testing of IM7/977-3 with Micro-Sized Particles

Ground-based hypervelocity imapct testing was conducted on IM7/977-3 quasi-isotropic flat panels at normal incidence using micron-sized particles (i.e. less than or equal to 100 microns) of soda lime glass and olivine. Testing was performed at room temperature (RT) and 175 C with results from the 175 C test compared to those obtained at RT. Between 10 and 30 particles with velocities ranging from 5 to 13 km/s impacted each panel surface for each test temperature. Panels were ultrasonically scanned prior to and after impact testing to assess internal damage. Post-impact analysis included microscopic examination of the surface, determination of particle speed and location, and photomicroscopy for microcrack assessment. Internal damage was observed by ultrasonic inspection on panels impacted at 175 C, whereas damage for the RT impacted panels was confined to surface divets/craters as determined by microscopic analysis

Nanotubular Toughening Inclusions

Conventional toughening agents are typically rubbery materials or small molecular weight molecules, which mostly sacrifice the intrinsic properties of a matrix such as modulus, strength, and thermal stability as side effects. On the other hand, high modulus inclusions tend to reinforce elastic modulus very efficiently, but not the strength very well. For example, mechanical reinforcement with inorganic inclusions often degrades the composite toughness, encountering a frequent catastrophic brittle failure triggered by minute chips and cracks. Thus, toughening generally conflicts with mechanical reinforcement. Carbon nanotubes have been used as efficient reinforcing agents in various applications due to their combination of extraordinary mechanical, electrical, and thermal properties. Moreover, nanotubes can elongate more than 20% without yielding or breaking, and absorb significant amounts of energy during deformation, which enables them to also be an efficient toughening agent, as well as excellent reinforcing inclusion. Accordingly, an improved toughening method is provided by incorporating nanotubular inclusions into a host matrix, such as thermoset and thermoplastic polymers or ceramics without detrimental effects on the matrix's intrinsic physical properties

Pyroelectric Sandwich Thermal Energy Harvesters

Systems, methods, and devices of the various embodiments provide pyroelectric sandwich thermal energy harvesters. In the various embodiment pyroelectric sandwich thermal energy harvesters, generated electrical energy may be stored in a super-capacitor/battery as soon as it is generated. The various embodiment pyroelectric sandwich thermal energy harvesters may harvest electrical energy from any environment where temperature variations occur. The various embodiment pyroelectric sandwich thermal energy harvesters may be power sources for space equipment and vehicles in space and/or on earth, as well as the for wireless sensor networks, such as health monitoring systems of oil pipes, aircraft, bridges, and buildings

The effect of Low Earth Orbit exposure on some experimental fluorine and silicon-containing polymers

Several experimental fluorine and silicon-containing polymers in film form were exposed to low Earth orbit (LEO) on a Space Shuttle flight experiment (STS-46, Evaluation of Oxygen Interaction with Materials, EOIM-3). The environmental parameters of primary concern were atomic oxygen (AO) and ultraviolet (UV) radiation. The materials were exposed to 2.3 plus or minus 0.1 x 10(exp 20) oxygen atoms/sq cm and 30.6 UV sun hours during the flight. In some cases, the samples were exposed at ambient, 120 C and 200 C. The effects of exposure on these materials were assessed utilizing a variety of characterization techniques including optical, scanning electron (SEM) and scanning tunneling (STM) microscopy, UV-visible (UV-VIS) transmission, diffuse reflectance infrared (DR-FTIR), x-ray photoelectron (XPS) spectroscopy, and in a few cases, gel permeation chromatography (GPC). In addition, weight losses of the films, presumably due to AO erosion, were measured. The fluorine-containing polymers exhibited significant AO erosion and exposed films were diffuse or 'frosted' in appearance and consequently displayed dramatic reductions in optical transmission. The silicon-containing films exhibited minimum AO erosion and the optical transmission of exposed films was essentially unchanged. The silicon near the exposed surface in the films was converted to silicate/silicon oxide upon AO exposure which subsequently provided protection for the underlying material. The silicon-containing epoxies are potentially useful as AO resistant coatings and matrix resins as they are readily processed into carbon fiber reinforced composites and cured via electron radiation

The UAN: A User-Oriented Representation for Direct ManipulationInterface Designs

Almost all existing interface representation techniques, especially those associated with UIMS, are constructional, focused on interface implementation, and therefore do not adequately support a user-centered focus. But it is the behavioral domain of the user that interface designers and evaluators do their work. We are seeking to complement constructional methods by providing a tool supported technique capable of specifying the behavioral aspects of an interactive system -- the tasks and the actions a user performs to accomplish those tasks. In particular, this paper is a practical introduction to use of the User Action Notation (UAN), a task- and User-oriented notation for behavioral representation of asynchronous, direct manipulation interface designs. Interfaces are specified in the UAN as a quasi-hierarchy of asynchronous tasks. At the lower levels, user actions are associated with feedback and system state changes. The notation makes use of visually onomatopoeic symbols, and is simple enough to read without much instruction. The UAN has been used by growing numbers of interface developers and researchers over the past few years. In addition to its design role, current research is investigating how the UAN can support the production and maintenance of code and documentation