We discuss the fabrication and performance of an all-polymer, flexural plate wave gravimetric sensor using flexible, piezoelectric Polyvinylidene fluoride as the substrate and an inkjet-printed interdigital transducer (IDT) employing conductive poly(3, 4-ethylenedioxythiophene) poly(styrenesulfonate) to excite Lamb waves within the film. Lamb waves are measured both electronically, using a second IDT, and mapped directly using a scanning laser Doppler vibrometer. Pulsed wave excitation is utilized to isolate the weak acoustic signal from the electromagnetic crosstalk, enabling the measurement of relative changes in the resonant frequency, f/ f 0 , in response to added mass, m, to the sensing area. A gravimetric mass sensitivity equivalent to f/( f 0 m) = −153 cm 2 /g is measured by mass loading the sensor with printed polymer layers. It is found that the low stiffness of the substrate contributes significantly to the response of the sensor, yielding a measured overall sensitivity of f/( f 0 m) = −83 cm 2 /g.

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Multi-campus synchronous teaching using teleconferencing involves teaching to a class in-person and remotely, simultaneously. As an approach to postsecondary learning, it can offer students greater variety, access to remote experts, and opportunities to collaborate across regions. There are significant challenges to successfully managing a multi-campus course, where ongoing observation and evaluation of student experience is important in guiding pedagogical practice. Herein we explore learning experiences of students who attended a course taught in a multi-campus format as part of a newdual-campus engineering program offered at the University of British Columbia. We chose a Community of Inquiry (CoI) surveying tool to assess student experience by examining their perceptions on teaching, social, and cognitive presence at both campuses. Data collected and analyzed with a Multivariate Analysis of Variance show a clear disparity between perceptions of Teaching Presence between the two campuses, with significance in both the Design & Organization and Direct Instruction CoI subcategories. The ease of performing a CoI survey and assessing its results renders this approach to continuous improvement feasible for regular evaluation and continuous improvement within the Bahmani and Hjelsvold conceptual framework for multi-campus coursedevelopment. The study was undertaken as part of continuous improvement within the engineering program, with results used to develop and inform multi-campus synchronous teaching best practices in a Canadian engineering context.

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