In recent times the need for educational research dedicated to engineering education has been recognised. This PhD project is a contribution to the development of engineering education scholarship and the growing body of engineering education research. In this project it was recognised that problem solving is a central activity to engineering. However, it was also recognised that the conditions for doing engineering are changing, especially in light of pressing issues of poverty and environmental sustainability that humanity currently faces, and as a consequence, engineering education needs to emphasise problem definition to a greater extent. One mechanism for achieving this, which has been adopted by some engineering educators in recent years, is through courses that explicitly relate engineering to social justice. However, creating this relationship requires critical interdisciplinary thinking that is alien to most engineering students. In this dissertation it is suggested that for engineering students, and more generally, engineers, looking at their practice and profession through a social justice lens might be seen as a threshold that needs to be crossed. By studying the variation present among students in three different courses at three different North American universities, the intention was to understand how students approach and internalise social justice as a perspective on engineering and/or develop their abilities to think critically. A conceptual model to frame the study was developed by combining elements of threshold concept theory and the educational research methodology, phenomenographic variation theory. All three of the courses studied operated on a similar basic pedagogical model, however, the courses were framed differently, with social justice in the foreground or in the background with the focus on, in one case, ethics and in the other, sustainability. All courses studied appeared to be successful in encouraging engineering students to engage in critical thinking and a similar general trend in the development of students’ conceptions of social justice was observed in each of the three courses. However, it does appear that if one is interested in developing an articulated understanding of social justice, with respect to engineering, that an explicit focus on social justice is preferable. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2010-04-07 13:12:29.207

The vascular endothelium is a single layer of cells that lines the interior surface of our blood vessels. The endothelium plays a key role in vasoprotection and vasoregulation and its proper function is therefore essential to the maintenance of vascular health. The endothelial cells respond to the frictional force (shear stress (SS)) that occurs with an increase in blood flow. As a response, vasoactive substances are released, causing the artery to dilate, this is termed flow-mediated dilation (FMD). Endothelial cell function can be assessed by measuring the vasodilatory response to an increase in SS. Currently however, our ability to interpret the results of FMD assessment in order to make accurate judgements regarding arterial health is hindered by an incomplete understanding of the “dose-response” relationship between SS and FMD. The dose-response relationship is characterized by 1) the SS stimulus required to elicit an FMD response (threshold), 2) the magnitude of dilation for a given increase in SS (the slope of the SS-FMD relationship), and 3) the point at which further increases in SS no longer elicit dilation (the ceiling). The primary purpose of the current study was to characterize the magnitude and day-to-day variability of the parameters described above. N=20 males (mean 22-years). Brachial artery diameter (BAD) and blood velocity (BV) were assessed with echo and Doppler ultrasound. SS was estimated as shear rate (SR=BV/BAD). Subjects performed 2 incremental handgrip exercise trials on two separate visits (V1 and V2). CV=co-efficient of variation. The SS-FMD relationship was characterized by a shallow slope followed by an inflection point (threshold (T1)) and a steeper slope (pre vs. post T1 slope p=0.002). There was no difference between V1 vs. V2 in the SR-FMD slope or threshold (p>0.05), but there was considerable within-subject variability in the SR-FMD parameters: pre-T1 slope CV = 47.0 ± 33.1%; post-T1 slope CV = 55.3 ± 40.7%; T1 CV = 25.6 ± 6.3%. In conclusion, %FMD did not plateau with increasing SR, therefore no ceiling was identified. The inflection in slope may indicate the involvement of different or additional vasodilator mechanisms post-threshold. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2011-09-15 20:17:11.582

A numerical study is performed to model the 2-D axisymmetric turbulent flow of supercritical water flowing upward in vertical pipes with constant wall heat fluxes, using ANSYS CFX v14.5. This study was aimed to use CFD in analyzing supercritical flow instability and heat transfer. Two types of flow instabilities are analyzed and results are compared with 1-D non-linear code solutions. Also, conditions for approximating the thresholds of instabilities based on steady-state results are assessed. It is determined that the results of instability thresholds obtained using the k-ɛ and the SST models are similar. Also the results of CFD and 1-D codes are different mainly due to the difference in the pressure drop predictions. Moreover, approximating the flow instability threshold by the conditions proposed holds true for a CFD solution. Results also indicate that Prt does not have a noticeable effect on the instability threshold for the cases examined.

This project is a point of departure for re-thinking one of the major tools of interior design practice - the wall. Ubiquitous in nature, the wall has a seemingly straightforward and simplistic understanding. The focus of this project is to re-examine it’s typical understanding, and re-situate it’s poetic presence within the built environment through a designed intervention. Through investigating theoretical concepts such as boundary, interiority and threshold, along with memory, trace, and void; an evolution of wall into poché begins to ensue. Poché is an alternate term used here to regard the hidden depth and dimensionality of the wall. Through an adaptive reuse methodology, a new use for a derelict industrial building in North St. Boniface has been redesigned into a community center for members of that given neighbourhood. Overall, the study facilitated a fresh understanding of both terms - poché and wall - then subsequently translated those findings into a designed interior.

This project is a point of departure for re-thinking one of the major tools of interior design practice - the wall. Ubiquitous in nature, the wall has a seemingly straightforward and simplistic understanding. The focus of this project is to re-examine it’s typical understanding, and re-situate it’s poetic presence within the built environment through a designed intervention. Through investigating theoretical concepts such as boundary, interiority and threshold, along with memory, trace, and void; an evolution of wall into poché begins to ensue. Poché is an alternate term used here to regard the hidden depth and dimensionality of the wall. Through an adaptive reuse methodology, a new use for a derelict industrial building in North St. Boniface has been redesigned into a community center for members of that given neighbourhood. Overall, the study facilitated a fresh understanding of both terms - poché and wall - then subsequently translated those findings into a designed interior.

Requirements of ultra-low power for many portable devices have drawn increased attention to digital sub-threshold logic design. Major reductions in power consumption and frequency of operation degradation due to the exponential decrease of the drain current in the sub-threshold region has made this logic an excellent choice, particularly for ultra-low power applications where performance is not the primary concern. Examples include RFID, wireless sensor networks and biomedical implantable devices. Along with energy consumption, security is another compelling requirement for these applications. Power analysis attacks, such as Correlation Power Analysis (CPA), are a powerful type of side channel attacks that are capable of performing a non-invasive attack with minimum equipment. As such, they present a serious threat to devices with secret information inside. This research analyzes sub-threshold logics from a previously unexplored perspective, side channel information leakage. Various transistor level and RTL circuits are implemented in the sub-threshold region as well as in the strong inversion region (normally the standard region of operation) using a 65 nm process. Measures, such as Difference of Mean Energies (DME), Normalized Energy Deviation (NED) and Normalized Standard Deviation (NSD) are employed to evaluate the implemented architectures. A CPA attack is also performed on more complex designs and the obtained correlation coefficients are used to compare sub-threshold and strong inversion logics. This research demonstrates that sub-threshold does not only increase the security against side channel attacks, but can also decrease the amount of leaked information. This research also shows that a circuit operating at sub-threshold consumes considerably less energy than the same circuit operating in strong inversion and the level of its instantaneous power consumption is significantly lower. Therefore, the noise power required to cover the secret information decreases and the attack may be dramatically more difficult due to major increase in the number of required power traces and run time. Thus, this research is important for identifying sub-threshold as a future viable technology for secure embedded applications.

No description available.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Thesis (M.Ost.)--Unitec New Zealand, 2006. / Includes bibliographical references (leaves 50-53).

[by] A.K. Susskind, D.R. Haring [and] C.L. Liu. / Includes bibliographies. / "AD 657370."