UIMSs are software components designed to handle the dialogue between user and application, enforcing a separation of application functionality from interface presentation and behaviour, by interpreting user input, pr...
详细信息
UIMSs are software components designed to handle the dialogue between user and application, enforcing a separation of application functionality from interface presentation and behaviour, by interpreting user input, providing feedback, controlling the execution of application actions and (ideally) handling application-generated output. Usually, a specification language is available for specifying the syntax of the user-computer dialogue, which is then linked to application functions and compiled into an executable program or interpreted at run-time. The Chimera UIMS is being developed as part of the Druid Project. The goal of Project Druid is to produce a highly interactive user interface design environment to support the style of design described above. Chimera is implemented in C and runs under Unix and the NeWS distributed window system on Sun 3 workstations. It consists of three parts: Chisl (a specification language), Chip (an interpreter) and Chime (an integrated multi-view editing environment). In various ways, each of these components provides support for the interactive design process.< >
Ray-tracing is an image synthesis method producing some of the most photorealistic images to date. The method is taken from classical optics, where rays of light are traced around a scene inside the computer and resul...
详细信息
Ray-tracing is an image synthesis method producing some of the most photorealistic images to date. The method is taken from classical optics, where rays of light are traced around a scene inside the computer and results are plotted into the resulting image. This simple technique enables refraction, reflection and shadowing to be created in the same algorithm. The drawback, however, is that the method is very computationally expensive, and hence requires accelerating to enable images to be produced in a reasonable time. Most of the time spent in any ray-tracing algorithm is spent in ray-object intersection tests, so techniques to accelerate the ray tracing process have concentrated on this problem. Two acceleration techniques are investigated, those of parallelism and temporal coherence.< >
Most manufacturing oriented simulation languages only offer the facility to model the system in one mode: discrete or continuous. However if a real, single mode system is examined more closely, some characteristics of...
详细信息
Most manufacturing oriented simulation languages only offer the facility to model the system in one mode: discrete or continuous. However if a real, single mode system is examined more closely, some characteristics of the opposing mode can usually be found. It is to what extent that the opposing mode can be neglected that determines in which mode the system can be successfully modelled. For many systems it is not satisfactory to approximate to a single mode system, and a mixed-mode systems simulation language would be required. A genuine mixed-mode simulation language would be able to model both discrete and continuous systems individually, in addition to combined continuous/discrete systems, and would therefore be a more useful general purpose simulation tool. It has been postulated that all systems should be treated as mixed-mode, with those with only discrete characteristics, or those with only continuous characteristics treated only as exceptions instead of the rule.< >
For many novice users the interface to Matlab can appear somewhat daunting. Users brought up on programs with a graphical user interface can find the command line interface presented by Matlab daunting. For average us...
详细信息
For many novice users the interface to Matlab can appear somewhat daunting. Users brought up on programs with a graphical user interface can find the command line interface presented by Matlab daunting. For average users, requiring the ability to perform tasks such as Control System Design and basic Signal Processing operations, numerous calls to Matlab routines need to be learnt to achieve even the simplest of results. In order to alleviate this obstacle and provide an easy to use and intuitive interface a graphical 'front end' employing the freely available Tcl/Tk programming toolkit is utilised to provide a point and click and drag and drop interface in order to enable rapid design and prototyping with minimal knowledge of the underlying computer engine, in this case Matlab.
Java has many powerful attractions as a platform for software development. In this paper, the author explains how developers of embedded systems can exploit its strengths to maximum advantage and describes how realisi...
详细信息
Java has many powerful attractions as a platform for software development. In this paper, the author explains how developers of embedded systems can exploit its strengths to maximum advantage and describes how realising the full benefits of Java technology in embedded applications requires a degree of optimisation.
It has been argued that the use of constraint-based techniques and tools allows the implementation of precise, flexible, efficient and extensible scheduling systems: precise and flexible as the system can take into ac...
详细信息
It has been argued that the use of constraint-based techniques and tools allows the implementation of precise, flexible, efficient and extensible scheduling systems: precise and flexible as the system can take into account any constraint expressible in the constraint language; efficient in as much as highly optimized constraint propagation procedures are now available; extensible as the consideration of a new type of constraint may require (especially in an object-oriented framework) only an extension to the constraint propagation system, or the implementation of additional decision-making modules (without needs for modification of the existing code). Yet there are a number of tradeoffs (between precision, flexibility, efficiency and extensibility) to consider when designing a scheduling system. These tradeoffs relate to: the representation of the scheduling problem; the set of control strategies to make available for the resolution of the problem; and the relation between the scheduling system and other information providing systems operating in the environment. Each of these three points suggests a different classification of scheduling problems and association of constraint-based techniques to scheduling problem classes.< >
Describes how we provided a way for transient users of a "virtual trade exhibition" on the Internet to create hypertext documents by acting rather than writing. "TaTTOO'95 On-line" was a set of...
详细信息
Describes how we provided a way for transient users of a "virtual trade exhibition" on the Internet to create hypertext documents by acting rather than writing. "TaTTOO'95 On-line" was a set of Internet-based online events, implemented using two key technologies: the World-Wide Web (WWW) and MOO. MOO (MUD, object-oriented) is a multi-user, text-based virtual world, based on MUD (Multi-User Dungeons or Multi-User Dimension). Users interact with each other by typing text commands in real time and reading the responses of other users from the screen. MOO is more than a simple "chat" system for a number of reasons. Firstly, users are situated in a virtual space, whereas simple chat systems disembody their users in the same way that the telephone does. Secondly, this virtual space may be constructed and customised by the users who inhabit it-the world is built by creating software objects for locations, people, books and so on. In this way, no two MOOs are alike, each developing its own identity and structure according to the needs and wishes of its inhabitants. Since MOO is text-based, we used the WWW to present the online events with additional information such as graphics. The two interfaces, MOO and WWW, were intended to coexist and to provide different ways to experience the events.
A rule based control system, known as 'RUBIC' (rule-based intelligent control), has been implemented in SmallTalk to run on a personal computer. RUBIC uses fuzzy logic to decipher the vaguely defined terms suc...
详细信息
A rule based control system, known as 'RUBIC' (rule-based intelligent control), has been implemented in SmallTalk to run on a personal computer. RUBIC uses fuzzy logic to decipher the vaguely defined terms such as 'high, low, OK', etc which are used in the control rules, e.g. IF (Temp is LOW) THEN (make a MEDIUM increase to fuel rate). A graphical interface tool, which is linked to every instance of a rule-based object, has been developed to make the system easy to use. The graphics make extensive use of the SmallTalk graphics primitives. The graphics tool is used for entering the control-rules and the fuzzy sets associated with ill-defined quantities such as LOW, HIGH, etc. RUBIC has been used to control temperature in a model of an exothermic reactor and level in a model of a spherical vessel. It is planned to use RUBIC for temperature control on an exothermic pilot plant reactor.< >
There has been considerable interest in applying sensor array signal processing techniques to a variety of radar applications. The use of adaptive spatial and temporal filtering techniques has been widely discussed. T...
There has been considerable interest in applying sensor array signal processing techniques to a variety of radar applications. The use of adaptive spatial and temporal filtering techniques has been widely discussed. The relative expense of building hardware and conducting experiments has led to a strong emphasis on simulation as a way of developing new equipment, but there are currently no software tools available that are particularly suited to the problems of simulating sensor array systems. This paper describes the current state of development of an adaptive array processing toolset (AdAPT), which is capable of modelling systems comprising large numbers of sensors. AdAPT encompasses modelling a target environment, design of array hardware, application and design of signal processing algorithms and the display and interaction of data as it flows through the design scenario. We also discuss the graphical user interface to AdAPT.
<正>This paper proposes an approach to the design of distributed parallel computing systems based on the concept of reflective middleware,skeleton parallel programming and object-oriented software *** the approach,t...
详细信息
<正>This paper proposes an approach to the design of distributed parallel computing systems based on the concept of reflective middleware,skeleton parallel programming and object-oriented software *** the approach,the programmer does not need to be bothered by the architectural ***,the approach provides support for the mostly used parallel paradigms,which will ease the onerous work for the programmer to construct the *** offers a method for the user to map the programming design seamlessly to the real environment.
暂无评论