The absence of efficient dual pairs of spanning trees in planar graphs

A spanning tree T in a finite planar connected graph G determines a dual spanning tree T* in the dual graph G such that T and T* do not intersect. We show that it is not always possible to find T in G, such that the diameters of T and T* are both within a uniform multiplicative constant (independent of G) of the diameters of their ambient graphs.Comment: 7 pages, 3 figure

Lockdown Pages: how to write your way through a pandemic

Online creative writing workshop presented for Creative Writing in Practice Symposium, University of Westminster

The Writing Circle: Creative hope in anxious times

Can a writing group make a difference in anxious times? In Autumn 2018 I was a sessional lecturer concerned by the growing number of students who identified as anxious and required learning support plans to help them cope. I wanted to understand the source of this anxiety: did students need writing support to help them feel less anxious – or was it writing that was causing their anxiety? I created a voluntary, non-assessed writing group for first-year students, The Writing Circle, intending it to grow as they did. And it did until 2020 when the pandemic shut campuses and moved us all online. Anxiety ramped up for students – and for me. Could a writing group like ours survive the move? And how could I learn to make a digital space feel intimate as well as inclusive? Through years of writing together on campus and online, through lockdowns and what came after, I’ve used a range of creative prompts and approaches to get us writing about and through feelings, aiming to diffuse anxiety as well as to address and challenge it. Throughout, students have become empowered to find new sources of confidence, to share early work and to write collaboratively, to make and publish work together. As the world is poised again for change, how can we stay nimble and responsive as practitioners, so that our writing groups continue to meet the needs of participants – and also to inspire us, to fulfil our creative hopes

Uncanny intimacies

Uncanny Intimacies discusses human-nonhuman relationships in a time of climate change through the writing of my novel, Seasalter

Innovative Opportunities for Elementary and Middle School Teachers to Maintain Currency in Mathematics and Science: A Community College-School System Partnership

Since 1992 the Manassas Campus of Northern Virginia Community College – in response to requests from local school systems – has developed four innovative methods of assisting elementary, secondary and middle school teachers to enhance their content knowledge in science and mathematics, as well as integrate curriculum units for classroom presentation. These methods are based on the assumptions that: - While teachers at this level have fundamental understanding of math and science, if they wish to incorporate new concepts or technologies from these fields, graduate level content courses are generally beyond their background level. - Community College faculty can often provide a bridge that connects advanced content in science and mathematics with the applications that can be adapted to elementary/middle school curriculum. - Presenting content to a mixed audience of teachers from K-8 allows teachers to see how content can be adapted to grade levels above and below. - Content delivery methods must be interactive and must be responsive to the multiple demands on these teachers’ time. This requires flexibility in scheduling and course requirements

Improving the performance of cascade correlation neural networks on multimodal functions

Intrinsic qualities of the cascade correlation algorithm make it a popular choice for many researchers wishing to utilize neural networks. Problems arise when the outputs required are highly multimodal over the input domain. The mean squared error of the approximation increases significantly as the number of modes increases. By applying ensembling and early stopping, we show that this error can be reduced by a factor of three. We also present a new technique based on subdivision that we call patchworking. When used in combination with early stopping and ensembling the mean improvement in error is over 10 in some cases

Study of space shuttle environmental control and life support problems

Four problem areas were treated: (1) cargo module environmental control and life support systems; (2) space shuttle/space station interfaces; (3) thermal control considerations for payloads; and (4) feasibility of improving system reusability