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Quantum state transition is the core content of quantum control. This paper presents a control scheme of the state evolution path based on feedback control and reverse engineering design. To achieve high-precision state transition, we first adopt a homodyne-based feedback control strategy to form a closed-loop system. Then, based on the idea of reverse engineering design, the state evolution path of the system is planned and designed by considering the influence of environment decoherence on the state evolution. Numerical simulation results show that the control pulse based on planning design can drive the system from any initial state to the desired target state, and the coherence of the system is effectively protected during state transition. [ABSTRACT FROM AUTHOR]

This paper addresses the design of wide-flange steel members subjected to torsional forces as well as axial forces and moments about their strong and weak axes. The current Canadian steel design standard (CSA S16-01) gives no specific guidance on methodology with respect to torsional design. Codes of other countries (American, British, Australian) provide useful insight but are different in format from the Canadian standard and cannot be used directly in conjunction with it. Specialized second-order finite element programs have the capacity for torsional analysis, but are too complicated and costly to use in design practice. There is, therefore, a need for a practical design method that would allow engineers to account for the effects of torsion simply and accurately. This paper, written by a practicing design engineer, suggests a number of approaches that, subject to discussion and approval by experts in the field, could constitute the basis for design of steel members in torsion. [ABSTRACT FROM AUTHOR]

In January 2002, the Intelligent Sensing for Innovative Structures (ISIS) Canada Networks of Centres of Excellence announced its first pedestrian bridge design competition for ISIS students. The bridge is located on the campus of the Université de Sherbrooke to provide a new access to the new east entrance of the Faculty of Engineering Building. The proposed design was required to convey the innovation and ingenuity of the ISIS Canada Research Network through the use of fibre-reinforced-polymer (FRP) materials. Based on these requirements, five graduate students from the Department of Civil Engineering at Queen's University joined forces to produce the winning conceptual design, demonstrating cost-effectiveness, visual stimulation, and innovation. This application paper presents details of the competition and the winning design for the pedestrian bridge as told by the winning design team. The bridge was built during the summer of 2002 at the Université de Sherbrooke. The objective of the paper is to present the student experience from this highly successful competition, and thus to promote similar design competitions for engineering students. [ABSTRACT FROM AUTHOR]

This paper describes the development of the 2004 Canadian Standards Association (CSA) A23.3 shear design provisions for reinforced and prestressed concrete structures. These methods are similar to the 1994 standard in providing a simplified and general shear design method. They differ from previous standards by providing a direct link between these two methods and simple equations for the calculation of β and θ used in the general method rather than providing these values in a table. The paper explains the basic assumptions behind the new shear provisions, provides a derivation of the new equations, and compares designs made with the new equations to designs obtained from previous standards. In general, the new shear provisions require slightly less shear reinforcement than that required by the previous standard. The new general method is significantly easier to use, particularly with spreadsheets. [ABSTRACT FROM AUTHOR]

One of the main factors concerning durability and service life of steel-reinforced bridges is corrosion of steel bars especially when exposed to a harsh environment. The use of glass fibre reinforcing polymer (GFRP) bars as non-corrosive material has emerged as an innovative solution to corrosion related problems, reduce the maintenance cost, and increase the service life of bridge structures. A recent cost-effective design of PL-3 bridge barrier was developed at Ryerson University incorporating high-modulus GFRP bars with headed ends. This paper presents results of full-scale static tests to collapse performed on the developed PL-3 bridge barrier at interior and exterior locations to investigate the ultimate load carrying capacity to be compared with Canadian Highway Bridge Design Code (CHBDC). The experimental ultimate load carrying capacity of the barriers was observed to be far greater than CHBDC factored design transverse load. The failure pattern was initiated by a trapezoidal crack pattern at the front face of the barrier, followed by punching shear failure at the transverse load location. Based on the punching shear failure developed in the barrier wall and comparison with available punching shear equations in the literature, an empirical punching shear equation is proposed to determine the transverse load carrying capacity of PL-3 bridge barrier walls reinforced with GFRP bars. [ABSTRACT FROM AUTHOR]

This paper aims to examine capillarity effect on flows in the drainage layer of highway pavement. A two-dimensional (2-D) model based on the Richards equation was used to simulate saturated and unsaturated flows in the drainage layer. For comparison, flows were also simulated using a 1-D Boussinesq equation based model and a 2-D model based on the Laplace equation, both assuming saturated flow only. The drainage layer was modeled with sand and gravel, which possess similar hydraulic properties to those of commonly used filling materials in practice. The results showed that the two saturated flow models agreed well with each other, indicating the dominance of horizontal flow in the drainage layer. However, their predictions differed significantly from those of the variably saturated flow models. The latter model predicted significant flow activities in a relatively large unsaturated zone, especially for a sandy drainage layer. Such unsaturated flow contributes to and enhances the capacity of the drainage layer. With the unsaturated flow neglected, the saturated flow models over-predicted the extent of the saturated zone and hence the groundwater table elevation. As the current engineering design of the drainage layer is typically based on the groundwater table elevation predicted by the saturated flow models, the finding of this study suggests that the design criterion is likely to lead to over-design of the drainage system. Further work is also required to prove the practical significance of the capillary effect and account for other factors. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental investigation into the hydraulic efficiency of a vertically oriented water intake. Under low submergence conditions, the operation of such an intake is affected significantly by the formation of surface vortices, which result in significant flow reduction and the downstream entrainment of air and swirl. The experimental work considered the fact that vortex formation is governed by the geometrical characteristics of the intake, including the diameter, local shape, submergence, surrounding boundary, etc, and the velocity distribution in the approaching flow. Therefore, an experimental study was conducted to investigate the influence that the local shape and the proximity to nearby boundaries have on the hydraulic performance of a vertical water intake. The results of this experimental investigation will hopefully lead to a better understanding of the phenomena governing the flow in such structures and to the elaboration of improved engineering design guidelines. [ABSTRACT FROM AUTHOR]

Residential construction has changed little in decades. In North America, houses are constructed predominantly with cast-in-place (CIP) concrete basement foundations and “custom-built” wood platform - framing structures. To improve the productivity of residential construction, a precast concrete foundation (PCF) system was developed by the University of Alberta and its industrial partners. Although the PCF system can be built much faster and better than conventional CIP foundations, it has not been considered a viable alternative in residential construction due to the belief that it is costly and less flexible. To overcome this perception, special research efforts were made to address issues of manufacturability, constructability, and standardization. This paper proposes an innovative design of the PCF system that satisfies functional requirements, while obtaining a minimum total cost and achieving flexibility. The unique features include a modularized rib structure, external insulation, and simplified bolted connections. A comparative analysis between PCF and traditional CIP concrete foundation systems is also presented. [ABSTRACT FROM AUTHOR]

The novel form of composite walling system consists of two skins of profiled steel sheeting with an infill of concrete. The knowledge of the behaviour of such walling under shear loading is important to use this system as shear elements in a steel framed building. Currently design provisions for this novel form of framed shear walling do not exist. This paper presents the results of tests on one-sixth scale models of the composite wall and its components, manufactured from very thin sheeting and microconcrete. The heavily instrumented small-scale tests provided information on the load–deflection response, strength, stiffness, strain condition, sheet–concrete interaction, and failure modes. Analytical models for the shear strength and stiffness of the wall are derived. The adequacy of design equations is validated through experimental results and finite element modelling. [ABSTRACT FROM AUTHOR]

This paper evaluates the moment equation in the 2000 Canadian highway bridge design code (CHBDC) for soil–metal arch structures. This equation is adopted from Duncan's moment equation (1978), which is based on his finding from finite element analyses that the maximum moment occurs at the quarter point of soil-metal structures. However, finite element analyses carried out for this study demonstrate that the maximum moment in soil–metal arch structures with spans greater than approximately 11 m occurs at the crown point. In this study, the location and magnitude of the maximum moment was examined for soil–metal arch structures having spans of 6–20 m under three construction stages; backfill up to the crown, backfill up to the cover depth, and live loading. Based on the location of the maximum moment, two sets of moment equations dependant on span length were found necessary. Moment coefficients and moment reduction factors in moment equations are proposed from the results of numerous finite element analyses for semi-circular arch and part-arch types of soil–metal structures considering the various design variables, such as span length, structural shapes, section properties, and backfill conditions. The validity of the coefficients and reduction factors in the moment equation of the 2000 CHBDC is investigated by comparison with those proposed in this study. The comparison demonstrates that the moment equation of the 2000 CHBDC is still valid and a little conservative. The effects of design variables on the variations of moments of soil–metal arch structures during construction stages are also examined. [ABSTRACT FROM AUTHOR]

The article presents a discussion of the paper "Making use of brace overstrength to improve the seismic response of multistorey split-X concentrically braced steel frames." The authors point out some inconsistencies present in the paper. They note that the first series of structures studied were designed without inclusion of P-delta effects that were included in the subsequent analyses. In addition, they contend that the lower base shear forces mandated by the 2005 National Building Code of Canada (NBCC) compared with those in the 1990 NBCC make P-delta effects more critical than earlier requirements are not insignificant.