The low-frequency asynchronous switch design (LF-ASD) was introduced as a direct brain-computer interface (BCI) technology for asynchronous control applications. The LF-ASD operates as an asynchronous brain switch (ABS) which is activated only when a user intends control and maintains an inactive state output when the user is not meaning to control the device (i.e., they may be idle, thinking about a problem, or performing some other action). Results from LF-ASD evaluations have shown promise, although the reported error rates are too high for most practical applications. This paper presents the evaluation of four new LF-ASD designs with data collected from individuals with high-level spinal cord injuries and able-bodied subjects. These new designs incorporated electroencephalographic energy normalization and feature space dimensionality reduction. The error characteristics of the new ABS designs were significantly better than the LF-ASD design with true positive rate increases of approximately 33% for false positive rates in the range of 1%-2%. The results demonstrate that the dimensionality of the LF-ASD feature space can be reduced without performance degradation. The results also confirm previous findings that spinal cord-injured subjects can operate ABS designs to the same ability as able-bodied subjects., Peer-reviewed article, Published. Manuscript received June 30, 2003; revised February 6, 2004.
The Neil Squire Society has developed asynchronous, direct brain switches for self-paced control applications with mean activation rates of 73% and false positive error rates of 2%. This report summarizes our results to date, lessons learned, and current directions, including research into implanted brain interface designs., Peer-reviewed article, Published. Manuscript received July 16, 2005; revised March 15, 2006; March 20, 2006.
Proceedings from Architectural Engineering Conference 2013, April 3-5, 2013 at State College, Pennsylvania, United States. Building performance is governed by physical processes, which are dynamically coupled in time and space, and whose degrees of interactions are often difficult to measure and appreciate. As a result, suboptimal performance and failures often occur. The goal of high-performance buildings is to optimize major aspects such as energy efficiency, life-cycle costs, and lighting, which are tightly coupled by the underlying physical processes. The premise behind this research project is that building integration/optimization can only be achieved when grounded on a shared understanding and communication of the underlying physical principles governing building performance, which can then enable the transformation of these principles into meaningful performance metrics. This paper proposes a methodology for building systems integration through building science principles. At the core of the methodology, a vocabulary of building science concepts, principles, and metrics enables using existing knowledge to increase understanding and gain insights on the systems involved in a particular design (including degrees of coupling, redundancies, and behaviours), which in turn facilitates the creation of new knowledge that may be needed to integrate new systems and technologies. A set of generic building science rules implemented using systems theory will enable such knowledge creation while preserving systems integrity at all times. The goal of this research is not to create a knowledge-base to replace building science professionals but to leverage an explicit vocabulary to increase understanding, learning, and communication of building performance for improved building integration. Furthermore, it is envisioned that the knowledge-base will serve as a bridge between building simulation, decision analysis, and optimization. This paper presents the initial attempt to organize a wealth of building science knowledge into a structured vocabulary. The power of generality and usability of the methodology will be tested with a case study. The expected benefits of the approach are three-fold: 1) to promote a more systematic approach to optimize building systems, 2) to facilitate the integration of new systems and technologies in buildings, and 3) to improve the education and dissemination of building science knowledge for improved building integration., Peer reviewed, Conference proceeding, Published.
The article focuses on the cost-benefit findings for ensuring workplaces are made accessible to disabled employees. Topics discussed include accessibility to workplaces in Canada; determining the financial benefit of built environment accommodations through employee retention; and savings in employee retention and retraining costs., Article, Published.
In the summer of 1988, a joint study was done by the Prosthetics and Orthotics Department at the British Columbia Institute of Technology and the Medical Engineering Resource Unit (MERU) of the University of British Columbia. The study was undertaken to determine the feasibility of applying existing Computer Aided Design-Computer Aided Manufacture (CAD-CAM) techniques to the design and manufacture of spinal orthoses. The orthosis design selected was a TLSO for the treatment of a non-structural curve of the spine. The results of the study were very promising. This paper describes the study and discusses the results., Peer-reviewed article, Published.
With advances in acute care for individuals with spinal cord injury (SCI), chronic conditions are becoming a central focus.1–3 More specifically, impairments in respiratory function are one of the leading causes of morbidity and mortality among individuals with SCI,4 and have significant economic burden. Paresis or paralysis of the respiratory muscles can lead to respiratory insufficiency, which has a major impact on cough effectiveness and susceptibility to infection.5–7 Prior studies have typically focused on breathing mechanics and pneumonia in the acute stages of SCI, but there is a dearth of evidence regarding secondary chronic conditions, such as asthma and chronic obstructive pulmonary disease (COPD), among SCI populations. In the general population, risk factors for the development of asthma and COPD include genetic, sociodemographic, and environmental components.8,9 In addition, traffic pollution and occupational exposures, and indoor exposure to pollutants such as mold, increase susceptibility to both diseases. However, that SCI may be an independent risk factor for COPD and asthma (or vice versa) has not been previously examined. It thus remains unknown whether there is a higher prevalence of chronic respiratory diseases (after adjustment for potential confounders) in individuals with SCI. The current study addresses this knowledge gap by utilizing the national Canadian Community Health Survey, which comprises comprehensive, up-to-date, cross-sectional data. Our aim was to estimate the prevalence of chronic respiratory outcomes in the SCI population, to compare their odds with a non-SCI population, and to investigate this relationship after controlling for confounders., Peer-reviewed article, Published. Received September 18, 2014; Accepted December 09, 2014.
A number of recent studies have identified and begun to quantify increased susceptibility of the infrastructure to climate change–induced carbonation of reinforced concrete. In this paper, the results of a study are presented which uses an updated empirical model to predict the diffusion coefficient of carbon dioxide (CO2) in concrete and thereafter, predict carbonation depths for a number of urban environments in the United States. Data from newer climate forecasts from the 5th Intergovernmental Panel on Climate Change assessment report are used to generate predictions for carbonation depths in four U.S. cities of varying geographic and climatic conditions (Los Angeles, Houston, Chicago, New York City). Results confirm that carbonation depths will increase in the future because of climate change. The magnitude of the increase is dependent on the climate-change scenario considered and the geographic location of the city. Whether or not the increases will require building code changes to increase concrete cover or improve concrete quality will be dependent on actual construction practices for the city in question., Peer-reviewed article, Published. Received: January 05, 2015; Accepted: July 30, 2015; Published online: October 28, 2015.
There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are effecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures. However, there is a lack of reliable models to predict the depth of carbonation as a function of time. To address this deficiency, a numerical model involving simultaneous solution of the transient diffusion and reaction equations of CO2 and Ca(OH)2 was developed. The model successfully includes the effects of variations in various properties such as porosity, humidity, temperature, atmospheric CO2 concentrations and chemical reaction rates. The applicability of the model was confirmed after calibration using data from accelerated carbonation experiments, and the model is used to evaluate the possible effects of climate change by inputting various future climate scenarios in Part 2., Peer-reviewed article, Published.
In Part1 of this paper, a carbonation model was developed and experimentally veriﬁed which was able to forecast carbonation depth of a concrete specimen considering varying ambient temperature, humidityand CO2 concentrations. Part 2 of the paper applies the carbonation diffusion/reaction model developed in Part 1 to predict the effects of global climate change on the carbonation of concrete. Climate scenarios were formulated and combined with the model for two major Canadian cities, Toronto and Vancouver. Results show that for undamaged and unstressed concrete, climate change will signiﬁcantly affect carbonation progress. The model showed that for unloaded, non-pozzolanic concrete, ultimate carbonation depths in Toronto and Vancouver could be up to 45% higher. For in-service structures under load, the rates of deterioration are likely to be even faster. This is a cause for concern, and much further effort must be devoted to fully understand these phenomena., Peer-reviewed article, Published. Received 18 October 2011; Revised 21 April 2012; Accepted 24 April 2012; Available online 10 May 2012.
There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are affecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures.In this paper, the serviceable life, from construction through to cracking due to carbonation induced corrosion of concrete infrastructure is considered in various cities throughout the world. It was concluded that global climate change will affect the progression and will result in much higher ultimate carbonation depths in the long term., Peer-reviewed article, Published. Received 23 May 2012; Revised 1 October 2012; Accepted 9 November 2012; Available online 25 December 2012.
Over the last decade, there have been marked changes in the trends of morbidity and mortality among individuals with spinal cord injury (SCI). With advances in acute care and in the management of septicemia, renal failure, and pneumonia, cardiovascular complications are now a leading cause of death in those with SCI.1 Moreover, several risk factors for cardiovascular disease (CVD) are amplified in individuals with SCI compared with able-bodied individuals, including physical inactivity, dyslipidemia, blood pressure irregularities, chronic inflammation, and abnormal glycemic control.2–22. While most of the literature with respect to CVD and SCI has shown a higher prevalence of risk factors for CVD,2–22 relatively few studies have examined the prevalence of CVD itself and corresponding risk estimates.23–26 None of these studies has provided direct comparisons of risk estimates for multiple CVD outcomes in the SCI population compared to a non-SCI population, with appropriate adjustment for confounding, in a large representative sample. It thus remains unknown whether there is excess risk of both heart disease and stroke (after adjustment for potential confounders) in individuals with SCI. The current study addresses this knowledge gap by utilizing the national Canadian Community Health Survey (CCHS), which is comprised of comprehensive, up-to-date, cross-sectional data. Our aim was to estimate the prevalence of heart disease and stroke outcomes in the SCI population, to compare their risk with a non-SCI population, and to investigate this relationship after controlling for confounders., Peer-reviewed article, Published. Received December 02, 2012 ; Accepted April 22, 2013.