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BCIT Citations Collection

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ABC region
Using a biophysical framework of analysis, this paper investigates the interconnections between the political, economic, social and environmental aspects of the de-industrialization of the ABC Region. Particular focus is given to the automobile sector and the responses of civil society and local government to the regional impacts of de-industrialization brought about by global forces. Questions about the role of social networks and the efficacy of government responses are addressed in the paper’s conclusion., Research paper, Published.
An action description language for iterated belief change
Proceedings of the International Joint Conference on Artificial Intelligence (IJCAI-07), Hyderabad, India, 2007. We are interested in the belief change that occurs due to a sequence of ontic actions and epistemic actions. In order to represent such problems, we extend an existing epistemic action language to allow erroneous initial beliefs. We define a non-Markovian semantics for our action language that explicitly respects the interaction between ontic actions and epistemic actions. Further, we illustrate how to solve epistemic projection problems in our new language by translating action descriptions into extended logic programs. We conclude with some remarks about a prototype implementation of our work., Conference paper, Published.
Active-arm passive-leg exercise improves cardiovascular function in spinal cord injury
In a 43-yr-old male subject with a chronic T3 AIS A spinal cord injury, the acute cardiorespiratory responses to active upper-extremity exercise alone and combined active-arm passive-leg exercise (AAPLE) were investigated, along with the cardiorespiratory, cardiac, vascular, and body composition responses to a 6-wk AAPLE interval training intervention. AAPLE elicited superior acute maximal cardiorespiratory responses compared with upper-extremity exercise alone. In response to a 6-wk interval training regimen, AAPLE caused a 25% increase in peak oxygen uptake, a 10% increase in resting stroke volume, and a 4-fold increase in brachial artery blood flow. Conversely, there were no changes in femoral arterial function, body composition, or bone mineral density in response to training. As a potential clinical intervention, AAPLE may be advantageous over other forms of currently available exercise, owing to the minimal setup time and cost involved and the nonreliance on specialized equipment that is required for other exercise modalities., Case reports, Published.
Adding modal operators to the action language A
Proceedings of the International Workshop on Non-Monotonic Reasoning (NMR-04) in Whistler, BC, 2004. The action language A is a simple high-level language for describing transition systems. In this paper, we extend the action language A by allowing a unary modal operator in the underlying propositional logic. The extended language requires very little new machinery, and it is suitable for describing transitions between Kripke structures. We consider some formal restrictions on action descriptions that preserve natural classes of Kripke structures, and we prove that the modal epistemic extension of A naturally subsumes related approaches to reasoning about knowledge. We conclude with some plans for future work. Introduction The action language A is a simple high-level language for reasoning about the effects of actions (Gelfond & Lifschitz 1993). The basic language is suitable only for simple action domains, but it has been extended several times to address a wide range of problems (Baral & Gelfond 1997; Baral, Gelfond, & Provetti 1997). In this paper, we suggest that it is possible to increase the representational power of A without changing the action language itself. Instead, we look at extending the underlying propositional logic by adding modal operators. We consider the expressive power of the modal extension, and compare the framework with related work on epistemic extensions of A., Conference paper, Published.
Application of a Whole-Building Hygrothermal model in energy, durability, and indoor humidity retrofit design
A building shall be classified as high performance building if it is energy efficient and durable and at the same time provides comfortable and healthy indoor environment for occupants. To achieve this objective, the hygrothermal performance of alternative building designs should be evaluated based on the simultaneous analysis of these three functional requirements rather than separately. In this article, a Whole-Building Hygrothermal model is used for evaluation of various retrofit design parameters that potentially enhance the overall performance of an existing residential house. The retrofit options considered in this study include changes to the reference house’s ventilation rate and operation, windows, insulation level, and various combinations of these options. Energy efficiency, building envelope and moisture management potential, indoor humidity control, and window condensation potentials are considered to be the four performance indicators in searching for a retrofit option that delivers an optimal performance. The hygrothermal simulation results indicate that changing a design parameter to improve one of the design goals may result in less optimal results in the other one or both goals, or even in some cases result in severe negative consequences., Peer reviewed article, Published. Article first published online: February 27, 2014; Issue published: July 1, 2015 .
Application of hygrothermal analyses to optimize exterior wall design
Proceedings of 2nd International Conference on Research in Building Physics: 14 September 2003, Leuven, Belgium. The design of exterior walls in a building envelope for optimum moisture management is a challenging task. Many conventional methods or local practice guidelines are available for this purpose, based primarily on regional traditions and with limited performance assessment records. In recent years, new wall systems and unconventional materials have been introduced in every part of North America for reasons such as aesthetic appeal, cost-effectiveness etc. However, neither the long-term moisture management performance of these new wall systems nor the uses of unconventional materials have been assessed rigorously. The primary reason for this lack of such assessment is the absence of a design-oriented technical routine toperform the task. Recent studies at the Institute for Research in Construction (IRC) / National Research Council (NRC) of Canada, show that such an assessment is possible with the use of an advanced hygrothermal modelling tool, such as hygIRC, developed in-house at IRC. This paper presents results from hygrothermal modelling and discussion on walls with the four different cladding systems: stucco, exterior insulated finish systems (EIFS), masonry and siding. These walls were virtually exposed to several North American climates. Their hygrothermal responses were assessed with a novel indicator, called the RHT index, which is derived from relative humidity and temperature. The results and discussion presented in this paper clearly show the need and usefulness of an integrated design methodology for the moisture management of exterior wall systems that can help to optimise various design considerations., Conference paper, Published. A version of this document is published in: Research in Building Physics, Leuven, Belgium, Sept. 14-18, 2003, pp. 417-426.
Application of hygrothermal modeling tool to assess moisture response of exterior walls
The moisture design of exterior walls in a building envelope is an important task that needs to be carried out systematically to generate a sustainable and healthy built environment. Many conventional methods or practice guidelines are available for this purpose, based primarily on local traditions and with limited performance assessment records. In recent years, with the rapid development of global free trade and economy, new wall systems and unconventional materials have been introduced in every part of the world for reasons such as aesthetic appeal, cost effectiveness and so on. However, neither the long-term moisture management performance of these new wall systems nor the uses of unconventional materials have been assessed in a systematic way. The primary reason for this lack of assessment is the absence of a design-oriented methodology to perform the task. This paper presents selected results from a recently completed research project that demonstrate that it is indeed possible to assess the moisture management performance of exterior walls in a systematic way, using a hygrothermal modeling tool together with key inputs from a limited number of laboratory and field investigations. In this project the hygrothermal responses of exterior walls and their components were assessed with a novel moisture response indicator, called the RHT index, which is derived from relative humidity and temperature data over a time period. The results and discussion presented in this paper clearly show the need and usefulness of the application of hygrothermal simulation tool for the optimum moisture design of exterior wall systems in various geographic locations, when sufficient information is available from laboratory and field experiments., Technical papers, Published. Received February 23, 2005; Accepted May 05, 2006; Published online December 01, 2006.
Application of modeling tool to assess moisture and thermal performance of retrofitted wall assemblies
Proceedings of CIB World Building Congress 2004: 02 May 2004, Toronto, Ontario. As the stock of buildings in Canada ages, it is expected that there will be an increase in building envelope rehabilitation work. Such activities represent an ideal opportunity to add insulation and reduce air leakage to improve energy efficiency and building envelope durability. However, there is very little information available on how to assess the moisture and thermal (i.e. energy) performance of retrofitted building envelope assemblies and select the optimum retrofit options that will maximize the energy efficiency without compromising the long-term moisture performance of the retrofitted building envelopes. This paper depicts selected results from a study that has used a two-dimensional hygrothermal simulation tool, hygIRC-2D, to assess thermal and moisture performance of retrofitted masonry walls used in high-rise construction. The performance analyses of three basic (i.e. base case) masonry wall systems (Brick Veneer - Steel Stud, Brick Veneer - Concrete Masonry, and Precast Concrete Panels - Steel Stud) with four retrofit options, located in the National Capital Region (Ottawa-Gatineau) of Canada, are presented in this paper. The results from the simulations indicate that hygrothermal simulation tools can be used to evaluate the thermal and moisture performance of various wall systems and associated retrofit options. Simulations results also indicate that with specific retrofit options the energy performance of the wall system can be improved significantly without compromising the moisture response of the wall by adding insulation and reducing air-leakage in the wall assembly. However, heat or energy loss through the wall system is directly proportional to the air-leakage characteristics of the wall system. In general, based on the results presented in this paper, it can be concluded that use of a hygrothermal simulation tool can help to identify potentially problematic retrofit strategies while more promising measures can be advanced for additional assessment through full-scale laboratory testing or field demonstration., Conference paper, Published. A version of this document is published in: CIB World Building Congress 2004, Toronto, Ontario, May 2-7, 2004, pp. 1-10.
Arbitrary announcements in propositional belief revision
Proceedings of the International Workshop on Defeasible and Ampliative Reasoning (DARe-15) in Buenos Aires, Argentina, July 27, 2015. Public announcements cause each agent in a group to modify their beliefs to incorporate some new piece of information, while simultaneously being aware that all other agents are doing the same. Given some fixed goal formula, it is natural to ask if there exists an announcement that will make the formula true in a multi-agent context. This problem is known to be undecidable in a general modal setting, where the presence of nested beliefs can lead to complex dynamics. In this paper, we consider not necessarily truthful public announcements in the setting of propositional belief revision. We are given a goal formula for each agent, and we are interested in finding a single announcement that will make each agent believe the corresponding goal following AGM-style belief revision. If the goals are inconsistent, then this can be seen as a form of ampliative reasoning. We prove that determining if there is an arbitrary public announcement in this setting is not only decidable, but that it is simpler than the corresponding problem in the most simplified modal logics. Moreover, we argue that propositional announcements and beliefs are sufficient for modelling many practical problems, including simple robot controllers., Conference paper, Published.
Assessment of building retrofit options using hygrothermal analysis tool
Proceedings of 7th Symposium on Building Physics in the Nordic Countries: 13 June 2005, Reykjavik, Iceland. As the stock of buildings in our society ages, it is expected that there will be an increase in building envelope rehabilitation work. Such activities represent an ideal opportunity to modify the existing wall system to improve building envelope durability and energy efficiency. This could be done by addition of insulation and sealing air leakage paths. However, there is very little information available on how to assess the moisture and energy (i.e. thermal) performance of retrofitted building envelope assemblies and select the optimum retrofit options that will maximize the long-term moisture performance and the energy efficiency of the retrofitted building envelopes together. This paper presents the findings from a study that has used a two-dimensional hygrothermal simulation tool, hygIRC-2D, to assess moisture and energy performance of retrofitted masonry walls used in high-rise construction for both residential and commercial types of buildings at various Canadian locations. The results from the simulations indicate that, if heat, air and moisture transport properties of the materials and the airflow characteristics of the systems can be defined properly a hygrothermal simulation tool can be used to evaluate the moisture and thermal (i.e. energy) performance of various wall systems and associated retrofit options., Published. A version of this document is published in: 7th Symposium on Building Physics in the Nordic Countries, Reykjavik, Iceland, June 13-15, 2005, pp. 1139-1146.
Assessment of natural ventilation effectiveness for an active NetZero energy house
This study was undertaken to investigate the effectiveness of an integrated natural ventilation design for a NetZero energy house in maintaining occupants comfortable solely by passive means. The house was instrumented and monitored during the warmest months of the year. A dynamic thermal model and a computational fluid dynamics (CFD) model were developed to supplement the measurements and help to understand the factors that contribute to the effectiveness of the design. A methodology was developed to validate the models with data and cross-validate them. Adaptive thermal comfort is used as the metric to determine if comfort has been achieved. The study concludes that the house as a whole meets the comfort target. Two technologies were compared through simulations to evaluate their effect on enhancing wind-induced natural ventilation. The technologies did not improve cooling performance in a significant manner. Further work is needed to improve the models through technologies testing in the laboratory and model the uncertainty of the boundary forces to increase confidence in the results., Peer reviewed, Peer reviewed article, Published online: 06 Sep 2016., Adaptive thermal comfort, Natural ventilation, Active house, NetZero energy house
Assessment of thermal comfort during surgical operations
The thermal environment was studied in two operating rooms at the Montreal General Hospital. Thermal comfort of the staff was assessed based on measurements of the environment during surgical operations and on questionnaires given to the staff. Infrared pictures of representative surfaces and people were also taken and, when possible, skin and core temperatures of the patient were also measured. The thermal resistance of clothing and the activity levels for all the people were estimated from published tables and previous research studies. Three thermal zones were studied: zone 1, bounded by the patient, the surgical staff, and the surgical lights; zone 2, the adjacent area; and zone 3, the farthest one. It was found that under the present environmental and personal conditions it is not possible to provide all groups of people with an acceptable thermal environment. In general, surgeons tend to feel from slightly warm to hot (they sweat very often), anesthesia staff and nurses from slightly cool to cold, and the patient from slightly cool to very cold (patients sometimes woke up shivering). In addition to questionnaires, thermal comfort was predicted based on Fanger ' PMV model, which assumes a uniform thermal environment. Based on Fanger's model, the air temperature that could have ensured satisfactory thermal comfort for the surgeon, under the particular conditions studied, was about 66 deg F (19 deg C). However, at that temperature, to remain in good thermal comfort, nurses and anesthetists must be clothed with at least 0.9 clo and the patient covered with at least 1.6 clo. In practice, however, the radiant temperature asymmetry from the surgical lights in zone 1, which ranges between 11 deg F (6 deg C) and 137 (7 deg C) over the operating table and between 18 deg F (1O deg C) and 22F (12 deg C) over the floor (at a level of 1.1 m), causes surgeons' dissatisfaction with the environment at any air temperature. Possible solutions to minimize radiation and its effects on the surgeons are discussed, which would permit ambient temperatures more favorable for the patient and all the staff., Peer reviewed, Conference proceeding, Published: 2001.

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