BCIT Citations Collection | BCIT Institutional Repository

BCIT Citations Collection

Pages

Cyber-Security vulnerabilities: an impediment against further development of Smart Grid
This chapter discusses anomalies which may not be attributed to expected operational deviations and/or mishaps associated with component failure and/or environmental conditions. The question here is: what are known cyber-security vulnerabilities which could be used to aid in the detection of patterns and signatures associated with various types of attacks and intrusions in the system which need to be detected and analyzed using Smart Grid's sensory data, such as Smart meter's and/or PMU's data, to help differentiate between "cyber-attacks in progress" as opposed to "expected system anomalies" due to operational failures of its components?, book chapter, published
Deafferentation and neurotrophin-mediated intraspinal sprouting
Axonal plasticity in the adult spinal cord is governed by intrinsic neuronal growth potential and by extracellular cues. The p75 receptor (p75(NTR)) binds growth-promoting neurotrophins (NTs) as well as the common receptor for growth-inhibiting myelin-derived proteins (the Nogo receptor) and so is well situated to gauge the balance of positive and negative influences on axonal plasticity. Using transgenic mice lacking the extracellular NT-binding domain of p75(NTR) (p75-/- mice), we have examined the influence of p75(NTR) on changes in the density of primary afferent (calcitonin gene-related peptide-expressing) and descending monoaminergic (serotonin- and tyrosine hydroxylase-expressing) projections to the dorsal horn after dorsal rhizotomy, with and without concomitant application of exogenous nerve growth factor and NT-3. We found that, in intact p75-/- mice, the axon density of all populations was equal to or less than that in wild-type mice but that rhizotomy-induced intraspinal sprouting was significantly augmented. Monoaminergic axon sprouting was enhanced in both nerve growth factor- and NT-3-treated p75-/- mice compared with similarly treated wild-type mice. Primary afferent sprouting was particularly robust in NT-3-treated p75-/- mice. These in vivo results illustrate the interactions of p75(NTR) with NTs, with their respective tropomyosin-related kinase receptors and with inhibitory myelin-derived molecules. Our findings illustrate the pivotal role of p75(NTR) in spinal axonal plasticity and identify it as a potential therapeutic target for spinal cord injury., Peer-reviewed article, Published. Received 14 August 2004; Revised 7 October 2004; Accepted 25 October 2004.
Design of a dynamic model of genes with multiple autonomous regulatory modules by evolutionary computations
A new approach to design a dynamic model of genes with multiple autonomous regulatory modules by evolutionary computations is proposed. The approach is based on Genetic Algorithms (GA), with new crossover operators especially designed for these purposes. The new operators use local homology between parental strings to preserve building blocks found by the algorithm. The approach exploits the subbasin-portal architecture of the fitness functions suitable for this kind of evolutionary modeling. This architecture is significant for Royal Road class fitness functions. Two real-life Systems Biology problems with such fitness functions are implemented here: evolution of the bacterial promoter rrnP1 and of the enhancer of the Drosophila even-skipped gene. The effectiveness of the approach compared to standard GA is demonstrated on several benchmark and reallife tasks., Peer-reviewed article, Published.
Detection and classification of sensory information from acute spinal cord recordings
One avenue of research for partial restoration of function following spinal cord injury is the use of neural prostheses, an example of which is functional electrical stimulation (FES) devices for motor functions. Neural prostheses may also be useful for the extraction of sensory information directly from the nervous system. We suggest the spinal cord as a possible site for the detection of peripheral sensory information from neural activity alone. Acute multichannel extracellular recordings were used to extract neural spike activity elicited from peripheral sensations from the spinal cords of rats. To test the recording method and classification potential, eight classes of sensory events were recorded consisting of electrical stimulation of seven locations on rat forepaws, and another class of data during which no stimulus was present. A dual-stage classification scheme using principal component analysis and k-Means clustering was devised to classify the sensory events during single trials. The eight tasks were correctly identified at a mean accuracy of 96%. Thus, we have shown the methodology to detect and classify peripheral sensory information from multichannel recordings of the spinal cord. These methods may be useful, for example, in a closed-loop FES for restoration of hand grasp., Peer-reviewed article, Published. Manuscript received October 24, 2005; revised February 25, 2006.
Determination of Aloin A and Aloin B in aloe vera raw materials and finished products by high-performance liquid chromatography
A single-laboratory validation (SLV) was conducted on an HPLC method for the detection and quantification of aloin A and aloin B in Aloe vera raw materials and finished products. An extraction procedure using sonication with an acidified solvent was used for solid test materials while liquid test materials only required dilution, if necessary, prior to filtration and analysis. Separation was achieved using a fused core C18 column in 18 min under isocratic elution conditions allowing for a single analyte (aloin A) calibration curve to quantify both aloins. Adequate chromatographic resolution (Rs ≥ 1) was achieved for aloin A and aloin B. The calibration curves for aloin A exhibited coefficients of determination (r(2)) of ≥ 99.9% over the linear range of 0.3-50 μg/mL. The LOD values were 0.092 and 0.087 μg/mL, and LOQ 0.23 and 0.21 μg/mL for aloin A and aloin B, respectively. Repeatability studies were performed on nine test materials on each of 3 separate days, with five of the test materials determined to be above the LOQ having repeatability RSD (RSDr) values ranging from 0.61 to 6.30%. Method accuracy was determined through a spike recovery study on both liquid and solid matrixes at three different levels: low, medium, and high. For both aloins, the recovery in the liquid matrix ranged from 92.7 to 106.3% with an RSDr of 0.15 to 4.30%, while for the solid matrix, the recovery ranged from 84.4 to 108.9% with an RSDr of 0.23 to 3.84%. Based on the results of the SLV study, it is recommended that this method be evaluated for reproducibility through a collaborative study., Peer-reviewed article, Published. Received January 27, 2013; Accepted by AP April 10, 2014.
Determination of indoor humidity profile using a whole-building hygrothermal model
During the design of a new building or retrofitting of an existing one, it is important to reliably assess the indoor humidity levels of the building as it can potentially affect the building envelope durability, occupants? comfort and health risks associated with mould growth. Simplistic assumptions of indoor humidity profiles, which ignore the dynamic coupling of the indoor environment and building enclosure, may lead to inaccurate conclusions about the indoor environment and moisture performance of the building enclosure. In this paper, a whole-building hygrothermal model called HAMFitPlus, which takes into account the dynamic interactions between building envelope components, mechanical systems and indoor heat and moisture generation mechanisms, is used to assess the indoor humidity condition of an existing occupied house. HAMFitPlus is developed on SimuLink development platform and integrates COMSOL multiphysics with MatLab. The basic input parameters of the model are discussed in detail, and its simulation results are presented. In general, the HAMFitPlus simulation results are in good agreement with the measured data., Peer reviewed article, Published article and manuscript
Determination of major phenolic compounds in Echinacea spp. raw materials and finished products by high-performance liquid chromatography with ultraviolet detection
A method previously validated to determine caftaric acid, chlorogenic acid, cynarin, echinacoside, and cichoric acid in echinacea raw materials has been successfully applied to dry extract and liquid tincture products in response to North American consumer needs. Single-laboratory validation was used to assess the repeatability, accuracy, selectivity, LOD, LOQ, analyte stability (ruggedness), and linearity of the method, with emphasis on finished products. Repeatability precision for each phenolic compound was between 1.04 and 5.65% RSD, with HorRat values between 0.30 and 1.39 for raw and dry extract finished products. HorRat values for tinctures were between 0.09 and 1.10. Accuracy of the method was determined through spike recovery studies. Recovery of each compound from raw material negative control (ginseng) was between 90 and 114%, while recovery from the finished product negative control (maltodextrin and magnesium stearate) was between 97 and 103%. A study was conducted to determine if cichoric acid, a major phenolic component of Echinacea purpurea (L.) Moench and E. angustifolia DC, degrades during sample preparation (extraction) and HPLC analysis. No significant degradation was observed over an extended testing period using the validated method., Peer-reviewed article, Published.
Determination of mitragynine in mitragyna speciosa raw materials and finished products by liquid chromatography with UV detection
Mitragyna speciosa (kratom) is a tree indigenous to Southeast Asia, and its leaves are used in herbal formulations because they contain indole alkaloids mitragynine and 7-hydroxy (7-OH) mitragynine. An HPLC method was developed, optimized, and validated using single-laboratory validation guidelines to quantify mitragynine in kratom raw materials and finished products. The method optimization evaluated several extraction parameters including solvent type, solvent volume, time, and extraction method. The separation of the mitragynine alkaloids was achieved in 18 min with a fused-core C18 EVO column using gradient separation with ammonium bicarbonate (pH 9.5) and acetonitrile. The calibration range for mitragynine was 1.0–500 μg/mL with correlation coefficients of ≥99.9% throughout method development and validation. The method detection limit and LOQ were 0.2 and 0.6 μg/mL, respectively for mitragynine. Eight test samples were obtained to evaluate method repeatability. RSDr ranged from 0.4 to 1.0%, whereas intermediate precision ranged from 3.7 to 7.3%, with HorRat values from 0.68 to 1.96. 7-OH mitragynine was below the LOQ for all samples, therefore, spikes repeatability sample RSD values were <1%. The validation data presented meet the Standard Method Performance Requirements as specified by the AOAC INTERNATIONAL Kratom Working Group., Peer-reviewed article, Published. Received July 12, 2016; Accepted by AP September 12, 2016.
Development and evaluation of an affordable lift device to reduce musculo-skeletal injuries among home support workers
Home support workers (HSWs) work in clients’ homes assisting with rehabilitation and activities of daily living. Like all health-care professionals, HSWs are at an increased risk for developing back injuries. Lift devices have been shown to reduce injuries to the worker. Presently, there are few lifting devices for home use that cost under $4000 CDN. Our study involved designing a safe and affordable lift device (retail cost under $2000 CDN) to be used by HSWs in the home and evaluating it in a typical bathroom. Thirty-eight HSWs and three seniors evaluated the BCIT lift, a commercially available lift (BHM Medical Inc.) and the manual method of transfer and lift. Results indicated that the BCIT lift was an improvement over the manual method of transferring, and approximated the more expensive, automatic lift in terms of perceived exertion, ease of use and safety. Feedback provided to the researchers has been incorporated into a new, ergonomically sound and marketable lift device., Peer-reviewed article, Published. Received 1 February 2003, Revised 27 January 2004, Accepted 23 February 2004, Available online 6 May 2004.
Development and evaluation of an interface pressure transducer for biomedical applications
The measurement of the interface pressure between a biomedical device and part of the human body is useful to aid in the design or improve the performance and safety of such devices. Therefore, a need exists for a transducer to measure interface pressure in these applications. The development and evaluation of an interface pressure transducer was the main goal of this research. Surgical retraction, surgical tourniquets and mammography were selected as demonstration applications for the developed transducer. These target applications were selected because they represented a wide spectrum of device and tissue characteristics and properties, and were in common use. A review of the available clinical, commercial and engineering literature identified a wide range of transducers and transducer technologies used for interface pressure measurement. The transducers included pneumatic/hydraulic, fibre-optic, strain based, capacitive and micromachined technologies. No standard method of measuring interface pressure was described and, in many cases, investigators cautioned against comparing-interface pressure measurements obtained using different measurement systems. From this review and an examination of the biomedical applications mentioned, the design criteria and optimal design specifications for an interface pressure transducer were defined. To gain a better understanding of the mechanical response of the interface between a device, transducer, and tissue to an applied loading, a preliminary finite element model was developed and studied. The model demonstrated the potential for shear stresses to develop between the transducer and interface materials. Furthermore a calibration system which simulated interface conditions was developed to evaluate both existing and developed transducers for use as interface pressure transducers. This evaluation demonstrated the lack of a transducer whose output was independent of the compliance of the interface materials. As well, an essential characteristic was identified for an effective interface pressure transducer that could be used in several applications where the interface material compliance was different. Based on the knowledge gained from the finite element analysis and existing transducer evaluation results, a novel interface pressure transducer was developed and evaluated both in the calibration system and via demonstration applications of surgical retraction and tourniquets. Under laboratory conditions in the calibration system, the transducer met many of the desired design specifications. The transducer was tested in the lab under both pneumatic and nonpneumatic tourniquet cuffs. The transducer worked well under the pneumatic cuff but required ] further development for use under the non-pneumatic cuff. The transducer was also integrated into a surgical retractor and evaluated in five clinical trials. It met many of the desired specifications for this application., Thesis, Published.
Development of a lightweight low-carbon footprint concrete containing recycled waste materials
Use of any recycled material helps to maintain a greener environment by keeping waste materials out of the landfills. Recycling practices also can decrease the environmental and economical impact of manufacturing the materials from virgin resources, which reduces the overall carbon footprint of industrial materials and processes. This study examined the use of waste materials such as crushed glass, ground tire rubber, and recycled aggregate in concrete. Compressive strength and elastic modulus were the primary parameters of interest. Results demonstrated that ground tire rubber introduced significant amounts of air into the mix and adversely affected the strength. The introduction of a defoamer was able to successfully remove part of the excess air from the mix, but the proportional strength improvements were not noted implying that air left in the defoamed mixture had undesirable characteristics. Freeze-thaw tests were next performed to understand the nature of air in the defoamed mixtures, and results demonstrated that this air is not helpful in resisting freeze-thaw resistance either. Overall, while lightweight, low-carbon footprint concrete materials seem possible from recycled materials, significant further optimization remains possible., Peer-reviewed article, Published. Received 4 April 2011; Revised 27 July 2011; Accepted 27 July 2011.
Development of an integrated staircase lift for home access
Purpose: Stairways into buildings present a significant environmental barrier for those with mobility impairments. A number of home access solutions that allow users to safely enter and exit the home exist; however, these all have some limitations. The purpose of this work was to develop a novel, inclusive home access solution that integrates a staircase and a lift into one device. Method: We developed an integrated staircase lift following a structured protocol with stakeholders providing feedback at various stages in the design process, consistent with rehabilitation engineering design methods. Results: A novel home access device was developed. The integrated staircase-lift has the following features: inclusivity, by a design that provides an option for either use of stairs or a lift; constant availability, with a lift platform always ready for use on either level; and potential aesthetic advantages when integrating the device into an existing home. The potential also exists for emergency descent during a power outage, and self-powered versions. Conclusions: By engaging stakeholders in a user-centred design process, we were able to gain insight into the limitations of existing home access solutions and get specific feedback on our lift concept. This information strengthened the development of a novel home access device., Peer-reviewed article, Published. Article first published online: July 16, 2015; Issue published: October 26, 2015.

Pages