This project proposes teaching-learning coupling as students take different roles during the course, from being learners, teachers, and proponents; finally, students take exams in a collaborative manner – initially, their exam is done individually followed by a team consultation period for the exam completion., Not peer reviewed, report
This paper presents a model of environmental regulation in the presence of measurement costs and asymmetric information. Environmental regulation can be viewed as a form of agency problem where the polluting firms may have better information about the true level of their abatement activities than the regulator. If certain aspects of environmental quality are costly to measure, regulators may resort to proxies to infer information about environmental quality. This may allow firms to circumvent the regulatory constraints by maximizing along those margins that are costly to measure. This problem is especially acute when a single firm produces multiple pollutants., Essay, Published.
Proceedings of the 3rd Building Enclosure Science & Technology (BEST3) Conference, Atlanta, USA, April 2-4, 2012. The thermal performance of two innovative pre-fabricated wood-frame wall systems was evaluated in comparison with a conventional 2x6 wood frame wall through one year’s field monitoring on BCIT’s Building Envelope Test Facility. Prefabricated wall system I has 4” Expanded Polystyrene (EPS) infill in the stud cavity with 1” additional EPS added on the interior side of 2x4 wood stud. Prefabricated wall system II has 4” EPS infill in the stud cavity only. The conventional 2x6 wood frame wall has 5-1/2” fiberglass insulation infill in the stud cavity. The effective thermal efficiency of these test walls is evaluated in terms of heat flux, effective in-situ R-values, and temperature distribution. The heat flux measurements show that, in comparison with the conventional 2x6 wood frame wall, prefabricated wall system I with 4” EPS infill in the stud cavity has 5.1% less heat loss and 16% less heat gain and the prefabricated wall system II with 1" extra EPS has 22.9% less heat loss and 37.5% less heat gain. The improvement of thermal efficiency in the prefabricated wall systems is mainly attributed to the significant improvement over the stud areas. Estimated effective R-values over the winter months from December 2008 to March 2009 show that the R-value over the stud area in prefabricated wall system I is improved by 32.7% while the R-value over the cavity area is reduced by 8.7%, resulting in a net improvement of effective wall R-value by 2.9%; and the R-value over the stud area in prefabricated wall system II is improved by 112.3% with only a 2.6% improvement in the R-value over the cavity area, resulting in a net improvement of effective wall R-value by 26.5%. Temperature measurements show that the interior surface temperatures over the stud area in the conventional wall fluctuate much more and are higher during the summer months and lower during the winter months compared to the prefabricated systems, due to the thermal bridging effect of the stud., Conference paper, Published.
This paper originates from a project done for and with the assistance of the Operations Strategy Branch, E Division, Royal Canadian Mounted Police. The aim of this study was to test a technological solution to two traditional limitations of information sharing between criminal justice agencies: data quality and privacy concerns. Entity Analytics Software (EAS) was tested in two studies with North American criminal justice agencies. In the first test, duplicated cases held in a police record system were successfully identified (4.0%) to a greater extent than the traditionally used software program (1.5%). This resulted in a difference of 11,954 cases that otherwise would not have been identified as duplications. In the second test, entity information held separately by police and border officials was shared anonymously between these two organizations. This resulted in 1,827 alerts regarding entities that appeared in both systems; traditionally, this information could not have been shared, given privacy concerns, and neither criminal justice agency would be aware of the relevant information held by the other. Data duplication resulted in an additional 1,041 alerts, which highlights the need to use technological solutions to improve data quality prior to and during information sharing. While only one potential technological solution (EAS) was tested and organizations must consider the potential expense associated with implementing such technology, the implications resulting from both studies for improved awareness and greater efficiency support and facilitate information sharing between criminal justice organizations., Research paper, Published.
Proceedings of 2012 IEEE Symposium on Computational Intelligence in Bioinformatics and Computational Biology (CIBCB) on 9-12 May 2012 in San Diego, CA, USA. We use in silico evolution to study the generation of gene regulatory structures. A particular area of interest in evolutionary development (evo-devo) is the correspondence between gene regulatory sequences on the DNA (cis-regulatory modules, CRMs) and the spatial expression of the genes. We use computation to investigate the incorporation of new CRMs into the genome. Simulations allow us to characterize different cases of CRM to spatial pattern correspondence. Many of these cases are seen in biological examples; our simulations indicate relative advantages of the different scenarios. We find that, in the absence of specific constraints on the CRM-pattern correspondence, CRMs controlling multiple spatial domains tend to evolve very quickly. Genes constrained to a one-to-one CRM-pattern domain correspondence evolve more slowly. Of these, systems in which pattern domains appear in a particular order in evolution, as in insect segmentation mechanisms, take the longest time in in silico evolutionary searches. For biological cases of this type, it is likely that other selective advantages outweigh the time costs., Conference paper, Published.
The co-evolution of species with their genomic parasites (transposons) is thought to be one of the primary ways of rewiring gene regulatory networks (GRNs). We develop a framework for conducting evolutionary computations (EC) using the transposon mechanism. We find that the selective pressure of transposons can speed evolutionary searches for solutions and lead to outgrowth of GRNs (through co-option of new genes to acquire insensitivity to the attacking transposons). We test the approach by finding GRNs which can solve a fundamental problem in developmental biology: how GRNs in early embryo development can robustly read maternal signaling gradients, despite continued attacks on the genome by transposons. We observed co-evolutionary oscillations in the abundance of particular GRNs and their transposons, reminiscent of predator-prey or host-parasite dynamics., Peer-reviewed article, Published.
Understanding how genetic networks act in embryonic development requires a detailed and statistically significant dataset integrating diverse observational results. The fruit fly (Drosophila melanogaster) is used as a model organism for studying developmental genetics. In recent years, several laboratories have systematically gathered confocal microscopy images of patterns of activity (expression) for genes governing early Drosophila development. Due to both the high variability between fruit fly embryos and diverse sources of observational errors, some new nontrivial procedures for processing and integrating the raw observations are required. Here we describe processing techniques based on genetic algorithms and discuss their efficacy in decreasing observational errors and illuminating the natural variability in gene expression patterns. The specific developmental problem studied is anteroposterior specification of the body plan., Peer-reviewed article, Published.
Proceedings of 8th IAPR International Conference, PRIB 2013, Nice, France, June 17-20, 2013. Early fruit fly embryo development begins with the formation of a chemical blueprint that guides cellular movements and the development of organs and tissues. This blueprint sets the intrinsic spatial coordinates of the embryo. The coordinates are curvilinear from the start, becoming more curvilinear as cells start coherent movements several hours into development. This dynamic aspect of the curvature is an important characteristic of early embryogenesis: characterizing it is crucial for quantitative analysis and dynamic modeling of development. This presents a number of methodological problems for the elastic deformation of 3D and 4D data from confocal microscopy, to standardize images and follow temporal changes. The parameter searches for these deformations present hard optimization problems. Here we describe our evolutionary computation approaches to these problems. We outline some of the immediate applications of these techniques to crucial problems in Drosophila developmental biology., Conference paper, Published.
Precipitation is one of the most common moisture sources on which building designers focus. Water comes from both top down and bottom up. Although foundations are sometimes constructed out of pressure-treated lumber, generally they are constructed from poured concrete. In a wet climate zone, the foundation of a house is often under continuous contact with moisture, which is mainly caused by rundown rainwater, wet soil, a high water table, or a combination of all these factors. This causes rot growth and decay of the wood-frame structure as it sits constantly on the damp foundation concrete. In this research, moisture transfer between concrete and wood is investigated under three different scenarios: a case with direct wood and concrete contact and two cases with different moisture barriers between the two materials. The moisture barrier materials considered in this study are the damp-proofing layer and sill plate gasket. The moisture transfer processes in these three cases are investigated in a field experimental setting using a customized experimental setup for 1 year. The experimental data suggest that using damp proofing and a sill gasket helps restrict moisture transfer., Peer reviewed article, Published. Received: May 29, 2015; Accepted: December 09, 2015; Published online: February 24, 2016.
An experimental investigation of the sound absorption characteristics of vegetated roof substrates and plots has been completed. First, an impedance tube was used to measure the normal-incidence absorption coefficients of substrates and their constituents. Substrates provided significant sound absorption, with coefficients varying from 0.03 at 250 Hz to 0.89 at 2000 Hz. Absorption increased with the percentage of organic matter and decreased with moisture content and compaction. A multi-variable regression model was developed for predicting the absorption of substrates. Secondly, the sound absorption of vegetated roof plots was investigated using the spherical-decoupling method. An optimal method, validated in an anechoic chamber, was used to determine the diffuse-field absorption coefficients of unplanted and planted rooftop test plots. Sound absorption increased with increased substrate depth (without vegetation) and decreased with the addition of vegetation and plant establishment. The mean noise reduction coefficient of established vegetated roof plots, with distinctly different plant communities in substrate depths of 50–200 mm, ranged from 0.20 to 0.63 when evaluated over a two-year period. The results confirm that the sound absorption of vegetated roofs is a function of substrate depth, plant community establishment, and moisture content in the plants and substrate., Peer-reviewed article, Published. Received 4 March 2015, Revised 22 April 2015, Accepted 23 April 2015, Available online 1 May 2015.