Fiscal Year 1996

PNNL successfully completed the three tasks: Task 1 - This task provided DISA with an updated set of design checklists that can be used to measure compliance with the Style Guide. These checklists are in Microsoft{reg_sign}Word 6.0 format. Task 2 - This task provided a discussion of two basic models for using the Style Guide and the Design Checklist, as a compliance tool and as a design tool

Second CLIPS Conference Proceedings, volume 1

Topics covered at the 2nd CLIPS Conference held at the Johnson Space Center, September 23-25, 1991 are given. Topics include rule groupings, fault detection using expert systems, decision making using expert systems, knowledge representation, computer aided design and debugging expert systems

SWM - Simple Window Manager

Tato práce se zabývá návrhem a implementací klasického (nedlaždicového) správce oken pro X Window System. Správce oken se stará o rozmístění a vzhled oken jednotlivých aplikací na obrazovce a je tedy klíčovou součástí jakéhokoliv moderního počítače s grafickým rozhraním. Ačkoliv již existuje mnoho správců oken, zejména pro X Window System, chybí zde jednoduchý nedlaždicový. Tato práce se snaží jeden takový vytvořit. Cílem bylo, aby splňoval freedesktop standardy ICCCM a EWMH a držel se UNIXové filozofie dělat jednu věc a dělat ji dobře. Důraz byl také kladen na jednoduchost, čitelný a testovatelný kód, a na to, aby byl správce oken snadno použitelný a rozšiřitelný.This thesis deals with the design and implementation of a stacking window manager for the X Window System. A window manager is the core component of any modern graphical desktop - it is responsible for the placement and appearance of application windows on the screen. While there is a plethora of window managers, especially on the X Window System, most of them are either heavyweight window managers that are part of a desktop environment or lightweight tiling managers. In this thesis, we try to fill the gap by developing a lightweight stackable window manager that complies with the freedesktop standards such as ICCCM and EWMH, and that follows the UNIX philosophy of doing one thing and doing it well. The focus has been on simplicity, code readability, testability, and making it easy to use and extend

A Graphical Environment Supporting the Algebraic Specification of Abstract Data Types

Abstract Data Types (ADTs) are a powerful conceptual and practical device for building high-quality software because of the way they can describe objects whilst hiding the details of how they are represented within a computer. In order to implement ADTs correctly, it is first necessary to precisely describe their properties and behaviour, typically within a mathematical framework such as algebraic specification. These techniques are no longer merely research topics but are now tools used by software practitioners. Unfortunately, the high level of mathematical sophistication required to exploit these methods has made them unattractive to a large portion of their intended audience. This thesis investigates the use of computer graphics as a way of making the formal specification of ADTs more palatable. Computer graphics technology has recently been explored as a way of making computer programs more understandable by revealing aspects of their structure and run-time behaviour that are usually hidden in textual representations. These graphical techniques can also be used to create and edit programs. Although such visualisation techniques have been incorporated into tools supporting several phases of software development, a survey presented in this thesis of existing systems reveals that their application to supporting the formal specification of ADTs has so far been ignored. This thesis describes the development of a prototype tool (called VISAGE) for visualising and visually programming formally-specified ADTs. VISAGE uses a synchronised combination of textual and graphical views to illustrate the various facets of an ADT's structure and behaviour. The graphical views use both static and dynamic representations developed specifically for this domain. VISAGE's visual programming facility has powerful mechanisms for creating and manipulating entire structures (as well as their components) that make it at least comparable with textual methods. In recognition of the importance of examples as a way of illustrating abstract concepts, VISAGE provides a dedicated tool (called the PLAYPEN) that allows the creation of example data by the user. These data can then be transformed by the operations belonging to the ADT with the result shown by means of a dynamic, graphical display. An evaluation of VISAGE was conducted in order to detect any improvement in subjects' performance, confidence and understanding of ADT specifications. The subjects were asked to perform a set of simple specification tasks with some using VISAGE and the others using manual techniques to act as a control. An analysis of the results shows a distinct positive reaction from the VISAGE group that was completely absent in the control group thereby supporting the thesis that the algebraic specification of ADTs can be made more accessible and palatable though the use of computer graphic techniques

Genome visualisation and user studies in biologist-computer interaction

We surveyed a number of genome visualisation tools used in biomedical research. We recognised that none of the tools shows all the relevant data geneticists who look for candidate disease genes would like to see. The biological researchers we collaborate with would like to view integrated data from a variety of sources and be able to see both data overviews and details. In response to this need, we developed a new visualisation tool, VisGenome, which allows the users to add their own data or data downloaded from other sources, such as Ensembl. VisGenome visualises single and comparative representations of the rat, the mouse, and the human chromosomes, and can easily be used for other genomes. In the context of VisGenome development we made the following research contributions. We developed a new algorithm (CartoonPlus) which allows the users to see different kinds of data in cartoon scaling depending on a selected basis. Also, two user studies were conducted: an initial quantitative user study and a mixed paradigm user study. The first study showed that neither Ensembl nor VisGenome fulfil all user requirements and can be regarded as user-friendly, as the users make a significant number of mistakes during data navigation. To help users navigate their data easily, we improved existing visualisation techniques in VisGenome and added a new technique CartoonPlus. To verify if this solution was useful, we conducted a second user study. We saw that the users became more familiar with the tool, and found new ways to use the application on its own and in connection with other tools. They frequently used CartoonPlus, which allowed them to see small regions of their data in a way that was not possible before

Attentional Selection in Object Recognition

A key problem in object recognition is selection, namely, the problem of identifying regions in an image within which to start the recognition process, ideally by isolating regions that are likely to come from a single object. Such a selection mechanism has been found to be crucial in reducing the combinatorial search involved in the matching stage of object recognition. Even though selection is of help in recognition, it has largely remained unsolved because of the difficulty in isolating regions belonging to objects under complex imaging conditions involving occlusions, changing illumination, and object appearances. This thesis presents a novel approach to the selection problem by proposing a computational model of visual attentional selection as a paradigm for selection in recognition. In particular, it proposes two modes of attentional selection, namely, attracted and pay attention modes as being appropriate for data and model-driven selection in recognition. An implementation of this model has led to new ways of extracting color, texture and line group information in images, and their subsequent use in isolating areas of the scene likely to contain the model object. Among the specific results in this thesis are: a method of specifying color by perceptual color categories for fast color region segmentation and color-based localization of objects, and a result showing that the recognition of texture patterns on model objects is possible under changes in orientation and occlusions without detailed segmentation. The thesis also presents an evaluation of the proposed model by integrating with a 3D from 2D object recognition system and recording the improvement in performance. These results indicate that attentional selection can significantly overcome the computational bottleneck in object recognition, both due to a reduction in the number of features, and due to a reduction in the number of matches during recognition using the information derived during selection. Finally, these studies have revealed a surprising use of selection, namely, in the partial solution of the pose of a 3D object

Sonar signal design and evaluation with emphasis on diver detection

Sonar-based underwater surveillance, including the problem of diver detection, is a challenging task. In harbors and coastal areas the environment is often reverberation dominated, due to the numerous backscattering objects and boundaries like ship wrecks, harbor walls, seabed, or the water surface. Reflections from the target and the background are often very similar, except for the fact that the target is typically moving and the background is not. The object movement causes a Doppler e_ect that can be used to improve the separation of moving objects from the quasi-stationary background. Therefore, the ideal active sonar transmit signal would simultaneously provide very good range and Doppler resolution. In this work, existing sonar signal designs are thoroughly analyzed and special emphasis is set to understand the sources of their advantages and disadvantages. Among all the investigated waveforms, frequency modulation (FM) signals have the best properties, but they lack Doppler selectivity that is required to detect small moving targets in reverberation limited environments. This motivates the development of a new design - called cutFM signal. The goal is to create a Doppler selective waveform based on a linear frequency modulated signal. The basic concept is to cut out frequency components from the base signal, in order to obtain a comb like spectrum. The effect of cutting is analyzed in detail and it is shown that the cutting period has to be carefully selected in order to achieve the desired result - a Doppler selective signal. The cutFM signal is compared theoretically and via simulations with corresponding known alternatives. It is characterized by a very good Doppler processing gain and excellent performance in reverberation limited channels. In addition, compared to the known continuous wave (CW) based signals that have equivalent Doppler processing gains, the cutFM signal provides improved range resolution

Playdate game development in C

Playdate is a new handheld console developed by Panic that will be launched in 2021. Its objective is offering a unique and surprising experience for videogame enthusiasts, and for that reason, it presents unconventional characteristics: in addition to the common directional and action buttons, it features a reflective monochromatic screen that draws only in pure black and white, an accelerometer, and a crank on its side that acts as a controller. This Bachelor’s Thesis will explore the videogame design possibilities stemming from such a peculiar hardware through the creation of several prototypes, covering all supported programming languages and evaluating them. In terms of performance, the Playdate falls on the modest side; for that reason, the focus will be in low-level programming to obtain the best performance possible. The knowledge acquired during this first phase will be applied to the development of a full game in C, “TinySeconds”. “TinySeconds” is a 2D platformer game where each level must be completed under 2.5 seconds. In addition to that limit, to progress to the next world the player must complete all the levels of the previous one in succession under an overarching time limit. This makes the game a frenetic experience with great replayability, as it invites the player to practice and improve their completion times. In addition to the time limit, different types of obstacles add variety to the levels making use of characteristics unique to the console, such as the crank. In addition to documenting the development of these projects, a C programming tutorial for Playdate will be included, teaching the basic principles of configuring the programming environment in Windows and developing a sample program. This chapter has the aim of supplying the lack of documentation about C programming for Playdate in a Windows platform, as the official manual is centered around the Lua language in Mac environments