Testing asynchronous logic circuits from transistor networks to gate-level designs.

This dissertation is concerned with testing of asynchronous circuits. Asynchronous circuits are attracting increasing interest for future generations of high-speed low-power logic circuits because they facilitate concurrent computation, offer average-case performance and better technology migration potential, and eliminate clock skew. The research reported in this dissertation is a comprehensive study of testing asynchronous circuits using design-for-testability (DFT) techniques and test generation algorithms. In the first part of the study we propose an on-line DFT technique for detecting short defects (or IDDQ faults), which create a low-resistance path between the supply lines. It is shown that I DDQ testing, delay testing, and stuck-open testing are necessary in order to achieve a high defect coverage. The second DFT technique presented in this part is a novel circuit for concurrently detecting delay faults and stuck-open faults. In the proposed DFT techniques, in particular, fault detection in CMOS logic family is investigated. The second half of this study attempts to derive test sequences for sequential circuits. First, initialization phase is studied. Initialization is the process of driving the state signals in the circuit to known states. This dissertation presents an initialization technique for non-initializable asynchronous sequential circuits. Finally, we proceed by generating test sequences for asynchronous sequential circuits. We assume the presence of all multiple faults of all multiplicities. No faulty machines are generated during these procedures and we do not resort to their explicit enumeration.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1999 .R33. Source: Dissertation Abstracts International, Volume: 61-09, Section: B, page: 4897. Adviser: Majid Ahmadi. Thesis (Ph.D.)--University of Windsor (Canada), 1999

An Automatic Image Processing System for Glaucoma Screening

Horizontal and vertical cup to disc ratios are the most crucial parameters used clinically to detect glaucoma or monitor its progress and are manually evaluated from retinal fundus images of the optic nerve head. Due to the rarity of the glaucoma experts as well as the increasing in glaucoma’s population, an automatically calculated horizontal and vertical cup to disc ratios (HCDR and VCDR, resp.) can be useful for glaucoma screening. We report on two algorithms to calculate the HCDR and VCDR. In the algorithms, level set and inpainting techniques were developed for segmenting the disc, while thresholding using Type-II fuzzy approach was developed for segmenting the cup. The results from the algorithms were verified using the manual markings of images from a dataset of glaucomatous images (retinal fundus images for glaucoma analysis (RIGA dataset)) by six ophthalmologists. The algorithm’s accuracy for HCDR and VCDR combined was 74.2%. Only the accuracy of manual markings by one ophthalmologist was higher than the algorithm’s accuracy. The algorithm’s best agreement was with markings by ophthalmologist number 1 in 230 images (41.8%) of the total tested images

Comparison of super-resolution algorithms applied to retinal images

A critical challenge in biomedical imaging is to optimally balance the trade-off among image resolution, signal-to-noise ratio, and acquisition time. Acquiring a high-resolution image is possible; however, it is either expensive or time consuming or both. Resolution is also limited by the physical properties of the imaging device, such as the nature and size of the input source radiation and the optics of the device. Super-resolution (SR), which is an off-line approach for improving the resolution of an image, is free of these trade-offs. Several methodologies, such as interpolation, frequency domain, regularization, and learning-based approaches, have been developed over the past several years for SR of natural images. We review some of these methods and demonstrate the positive impact expected from SR of retinal images and investigate the performance of various SR techniques. We use a fundus image as an example for simulations

Intelligent or smart cities and buildings: a critical exposition and a way forward

In the last decade, there has been an undoubtedly rising interest in the field of intelligent and smart built environments from design and construction to management, operational and governance perspectives. These recent endeavors, observed at both academic and professional levels, can be classified into city, neighborhood and building scales. In this context, understanding what we really mean by the word intelligent and smart is crucially important. This technical note attempts to clarify and further explore how intelligence differs from smartness in this context. Having intelligence as the main umbrella embracing other interrelated smart subsets is one way of thinking as supported by previous debates, while there are also other lines of thinking with more preference on the smartness as the core concept

A Conceptualized Hydrail Powertrain: A Case Study of the Union Pearson Express Route

hydrogen rail (hydrail) powertrain is conceptualized in this study, using drive cycles collected from the trains currently working on the Union Pearson Express (UPE) railroad. The powertrain consists of three preliminary different subsystems: fuel cell, battery, and hydrogen storage systems. A backward design approach is proposed to calculate the time-variable power demand based on a &ldquo route simulation data&rdquo method. The powertrain components are then conceptually sized according to the calculated duty cycle. The results of this study show that 275 kg of hydrogen is sufficient to satisfy the daily power and energy demand of a hydrogen locomotive with drive cycles similar to the ones currently working on the UPE rail route. Document type: Articl