Computer-aided design

This thesis outlines the design philosophy and implementation aspects of a new interactive CAD tool implemented in BASIC language on an IBM PC/AT computer for single input single output (SISO) digital control systems. The direct Digital Control design method presented is classical in nature. The program main features are: (1) The use of Modified z-transform to model the effects of transport delay due to control computation time. (2) The use of windows on a split screen to allow the designer observation of the closed-loop step response while systematically shaping a root locus or synthesizing closed-loop pole/zero patterns. (3) Display of system response in between sampling instants.

This paper describes an Automated Software Development Methodology (ASDM)
that encompasses a formal model for characterizing the specifications of a system
that will ultimately manifest itself in a software system. This paper focuses on the
semantic specification model of ASDM and the architecture of a knowledge-based
expert system (KBES) supporting the semantic model. ASDM is a
knowledge-based expert system, because it provides expertise and assistance m
the construction of formal requirement and design specifications while hiding the
formal specification techniques and semantic model from the user. ASDM is a
knowledge-based system, because the system represents formally characterized
knowledge of the ASDM semantic model, and it represents application domain
specific knowledge of a problem domain. Lastly, this paper introduces the
concept of an Application Domain Communication Model (ADCM), with its
associated characterization and interpretation facilities, for defining a set of user
interface scenarios that represent a cognitive model of an application domain
engineering world.

A method to create 3D-face image using 2D-face images is the objective of this research. The 3D-face image is constructed using a set of 3D-face images of other persons available in a face database. The 3D-face image actually depicts a parameterized form in terms of depth and texture. This concept can be used to facilitate creating a 3D-face image from 2D database. For this purpose, a 3D-face database is first developed. When a 2D-face image is presented to the system, a 3D-face image that starts with an average 3D-face image (derived from the 3D-face database) is projected onto the 2D-image plane, with necessary rotation, translation, scaling and interpolation. The projected image is then compared with the input image; and, an optimization algorithm is applied to minimize an error index by selecting 3D-depth and texture parameters. Hence, the projected image is derived. Once the algorithm converges, the resulting 3D-depth and the texture parameters can be employed to construct a 3D-face image of the subject photographed in the 2D-images. A merit of this method is that only the depth and texture parameters of the compared images are required to be stored in the database. Such data can be used either for the recreation of a 3D-image of the test subject or for any biometric authentication (based on 3D face recognition). Results from an experimental study presented in the thesis illustrate the effectiveness of the proposed approach, which has applications in biometric authentication and 3D computer graphics areas.

The increasing system design complexity is negatively impacting the overall system design productivity by increasing the cost and time of product development. One key to overcoming these challenges is exploiting Component Based Engineering practices. However it is a challenge to select an optimum component from a component library that will satisfy all system functional and non-functional requirements, due to varying performance parameters and quality of service requirements. In this thesis we propose an integrated framework for component selection. The framework is a two phase approach that includes a system modeling and analysis phase and a component selection phase. Three component selection algorithms have been implemented for selecting components for a Network on Chip architecture. Two algorithms are based on a standard greedy method, with one being enhanced to produce more intelligent behavior. The third algorithm is based on simulated annealing. Further, a prototype was developed to evaluate the proposed framework and compare the performance of all the algorithms.

The intent of this thesis is to focus on evocative objects to explore what is lost in the transition from tangible to digital and how personal meaning is altered by digitalization. "We are witnessing the sudden dematerialization of our arts and entertainment, their transfer from unique artifacts to universal on-demand screen availability."1 As we replace objects like photographs, books and music CDs with intangible digital versions, social and physical experiences get reconfigured. With more time being spent on-line, there is a growing emphasis on exchanging digital content and the network of self-projections shared virtually. As we continue towards an increasing digital environment, understanding emerging socio-cultural practices can provide insight into new directions for graphic design.