Journals at Carleton University
Not a member yet
3434 research outputs found
Sort by
Art galleries and mobile guards: revisiting O\u27Rourke\u27s proof
No full textO\u27Rourke (1983) proved that every -vertex polygon, with , can be guarded by edges or diagonals—a variant of Chvátal\u27s theorem for sufficiency of vertices. We present a short proof for a somewhat stronger result that allows us to impose some constraints on the guards. We prove that for every given subset of vertices, the polygon can be guarded by edges or diagonals that include at least one edge or diagonal incident to every vertex of . This bound is the best achievable given the constraint for . Our proof is by induction and suggests a simple linear-time algorithm after triangulating the polygon. The sufficiency of guards is a special case of the new result where is the empty set
Discrete Fréchet distance oracles
No full textIt is unlikely that the discrete Fréchet distance between two curves of length can be computed in strictly subquadratic time. We thus consider the setting where one of the curves, , is known in advance. In particular, we wish to construct data structures (distance oracles) of near-linear size that support efficient distance queries with respect to in sublinear time. Since there is evidence that this is impossible for query curves of length , for any \alpha > 0, we focus on query curves of (small) constant length, for which we are able to devise distance oracles with the desired bounds.
We extend our tools to handle subcurves of the given curve, and even arbitrary vertex-to-vertex subcurves of a given geometric tree. That is, we construct an oracle that can quickly compute the distance between a short polygonal path (the query) and a path in the preprocessed tree between two query-specified vertices.
Moreover, we define a new family of geometric graphs, -local graphs (which strictly contains the family of geometric spanners with constant stretch), for which a similar oracle exists: we can preprocess a graph in the family, so that, given a query segment and a pair of vertices in , one can quickly compute the smallest discrete Fréchet distance between the segment and any -path in . The answer is exact, if , and approximate if t>1
Assessing Professional Rapport: A Review of Current Measures and Best Practices
No full textBuilding rapport in professional settings, such as police interviews, fosters a non-coerciveenvironment that encourages information disclosure.
There is significant inconsistency in defining and measuring rapport, impacting the effectivenessof training and guidelines.
A reliable and practical measure of professional rapport is crucial for assessing and improvinginterview practices
Интернарративность авторитарного правления: нарративный анализ речей Владимира Путина в 2012–2019 гг.
No full textThis research examines how Russia, with a focus on Putin, shapes its messages by analyzing his interactions with foreign journalists between 2012 and 2019. To understand how these messages work together, the study employs the concept of ‘internarrativity,’ which explores how narratives are interlinked and reinforce one another. The author argues that it is essential to analyze communication narratives as interconnected webs of meaning, rather than independently. The study\u27s findings illustrate how Putin\u27s concept of a ‘Strong hand’ government system is constructed and strengthened by other associated narratives, legitimizing the need for authoritarian control in Russia for both national and international audiences.L’auteur se penche sur la question de l’internarrativité dans les discours de Vladimir Poutine de 2012 à 2019 : il examine, en particulier, comment différentes trames narratives s’y entremêlent pour légitimer la gouvernance autoritaire. À travers une analyse du discours alimentée par le codage qualitatif de 201 allocutions, l’auteur identifie 40 trames narratives qui se coupent et recoupent pour former une véritable « toile de sens », une vision du monde cohérente. Son analyse révèle que le récit central de la « main de fer », c’est-à-dire l’autorité stricte de Poutine essentielle à son régime autoritaire, est constamment renforcé par des appels aux thèmes de la résilience historique, de la souveraineté, des menaces extérieures et de la supériorité morale. Ces quatre trames narratives servent à justifier la centralisation du leadership entre les mains d’un seul homme, car elles le présentent comme garant de la stabilité interne de la Russie et de son influence internationale. L’auteur inscrit l’internarrativité dans les domaines des relations internationales, de la diplomatie et de la narratologie, ce qui lui permet de conclure que la nature dynamique des discours politiques participe au façonnement de l’identité nationale et des postures géopolitiques. Il identifie également des lacunes dans l’état de l’art : la recherche pourrait s’intéresser à la résonance socio-culturelle de ces récits et à leur malléabilité dans des contextes politiques changeants. Ce travail représente une avancée dans la compréhension des stratégies discursives des régimes autoritaires.Статья анализирует концепцию интернарративности в речах Владимира Путина в период с 2012 по 2019 годы, обращая внимание на то, как взаимосвязанные нарративы легитимируют авторитарное управление. На основе дискурс-анализа и качественного кодирования 201 речи автор идентифицирует 40 ключевых нарративов и показывает, каким образом их взаимодействие формирует целостную «сеть смыслов». Анализ выявляет, что центральный нарратив «сильной руки» последовательно подкрепляется темами исторической устойчивости, суверенитета, внешних угроз и морального превосходства. В совокупности эти нарративы оправдывают централизованную власть как необходимое условие внутренней стабильности и международного влияния России. Соотнося интернарративность с более широкими темами, такими как международные отношения, публичная дипломатия и теория нарративов, статья подчёркивает динамический характер политического дискурса, формирующего национальную идентичность и геополитическое позиционирование. Также обозначены направления для дальнейших исследований, включая социокультурный резонанс нарративов и их адаптивность в меняющихся политических условиях. Работа способствует углублению понимания нарративных стратегий в авторитарных режимах
Metric and geometric spanners that are resilient to degree-bounded edge faults
No full textLet be an edge-weighted graph, and let be a subgraph of . We say that is an -fault-tolerant -spanner for , if the following is true for any subset of at most edges of : For any two vertices and , the shortest-path distance between and in the graph is at most times the shortest-path distance between and in the graph . The value of is called the stretch factor. Numerous results are known for constructing such spanners, both for general graphs and for complete graphs whose vertex set is a set of points in or in a metric space of bounded doubling dimension.
Bodwin, Haeupler, and Parter [SODA 2024] generalized this notion to the case when can be any set of edges in , as long as the maximum degree of is at most . For example, if , then can be a perfect matching in . They gave constructions for general graphs .
We present three new results for constructing spanners that are resilient to edge faults of maximum degree .
We first consider the case when is a complete graph whose vertex set is an arbitrary metric space. We show that if this metric space contains a -spanner with edges, then it also contains a graph with at most edges, that is resilient to edge faults of maximum degree and has stretch factor . We also give an example for which our construction has stretch factor . If , the graph has at most edges and its stretch factor is at most . For this case, we give an example for which has stretch factor arbitrarily close to .
Next, we consider the case when is a complete graph whose vertex set is a metric space that admits a well-separated pair decomposition. We show that, if the metric space has such a decomposition of size , then it contains a graph with at most edges, that is resilient to edge faults of maximum degree and has stretch factor at most , for any given \varepsilon > 0. For example, if the vertex set is a set of points in ( being a constant) or a set of points in a metric space of bounded doubling dimension, then the spanner has edges.
Finally, for the case when is a complete graph on points in , we show how natural variants of the Yao- and -graphs lead to graphs with edges, that are resilient to edge faults of maximum degree and have stretch factor at most , for any given \varepsilon > 0
Using Specific Primers in PCR to Discern White Footed Mice (Peromyscus leucopus) From Deer Mice (Peromyscus maniculatus)
No full textDeer and white-footed mice have been known to carry illnesses hazardous to human health and other wildlife. Lyme disease and hantavirus pulmonary syndrome pose a threat to human health and have a direct relationship with Peromyscus mice. Warfarin is a common rodenticide used to control these species and reduce disease risk, however genetic resistance to warfarin can occur. The purpose of the study is to use PCR to discriminate white-footed mice (Peromyscus leucopus) from deer mice (Peromyscus maniculatus) for future assessment of mice that have warfarin-resistance. We successfully extracted DNA and tested universal primers on our samples observing white-footed mice at ~159bp. A meadow vole was observed ~220bp, no deer mice were found in the sample set. 52OC was the optimal temperature for primer annealing in this study. Our next step will be to test these primers on a confirmed deer mouse and use these samples for subsequent warfarin-resistance analysis. Through the identification of deer mice and white-footed mice, researchers can optimize current rodent control strategies to ensure proper disease control in the future
CA2 Spine Density in an In-Vivo Model of Autism Spectrum Disorder
No full textAutism spectrum disorder (ASD) is a neurodevelopmental disorder, characterized by a wide range of social and behavioral symptoms. Pathophysiology of ASD in humans is highly variable, however, there are differences seen in spine morphology and density, specifically in the hippocampus, which is involved in social memory. Treatment of ASD is limited, targeting only certain symptoms, through both pharmacological and non-pharmacological methods. Prenatal exposure to valproic acid (VPA) can create an animal model of ASD that shows similarities to the pathophysiology of ASD in humans. Animal models of ASD can provide the framework for developing treatments targeted towards the underlying neurobiology of ASD and a wider range of symptoms. This study used a VPA-induced mouse model of ASD to examine dendritic spine density and morphology within the CA2 region of the hippocampus, a region implicated in social memory. Neuron reconstruction was performed using Neurolucida (MicroBrightField, Williston, VT, USA) at a magnification of 100x. Neurons within the CA2 of the hippocampus were traced, and spines were quantified as thin, mushroom, or stubby. Reconstruction was done with set criteria to ensure consistency across brain slices. There were no significant changes observed in thin and total spine density between treatments, but a significant decrease in thin spine density in females was observed. A significant increase in stubby spine density and decreased mushroom spine density were observed in the VPA treatment groups. Future studies may investigate additional brain regions and spine density after VPA exposure to further the development of viable treatment options
Reflective and Active Learning on Education in Canada Today
No full textDuring my SAPP project, “Reflective and Active Learning on Education in Canada Today” with Dr. Patricia Kmiec , I used my previous experience as a student to redesign eight in-class activities. The activities included individual, small group (3-4 students), and large group (4-7 students) activities. I had completed the course in Winter of 2022 and knew my student perspective would be valuable when completing this project. My three goals for each activity were to develop: 1) clear instructions for students before beginning, 2) questions to consider during the activity, and 3) self-assessment questions to promote reflection and active learning. Thinking back to when I completed the course, I wanted to encourage students to speak up with their thoughts, opinions, and ideas about the course material. Helping students interact with their peers helps to build relationships, critical thinking skills, and the ability to collaborate with groups to reach a similar goal. Throughout my academic career, I have realized the value of smaller group class discussions and how these discussions can positively impact self-confidence in students. It is with our hope that each student that takes SOCI 3300 with Dr. Kmiec leaves with the belief that they can actively contribute, listen, and think about many different topics in all areas of life
A Preliminary Review of the WELL Building Standard
No full textThe natural and built environment can both affect our health and well-being; as nature affects our health, so do buildings – the spaces where we spend most of our time. The WELL Building Standard (or “WELL”) is a voluntary rating system that aims to support, maintain, and promote occupant health and well-being in buildings. The literature indicates increased documentation and evaluation of WELL implementations, but their impact remains unclear. This research aims to study the extent of the effectiveness and impact of WELL implementation in buildings, how it compares to more established rating systems, and directions for future research. A three-step methodology was conducted for this literature review, including (i) an article search, screening, and selection using the Scopus database; (ii) a detailed review of articles evaluating the effectiveness of WELL and comparing WELL to other rating systems; and (iii) a bibliometric analysis of the studies to map and understand how the field has evolved. Preliminary results indicate that WELL-certified buildings generally have higher satisfaction with mental health, well-being, and productivity than non-WELL-certified buildings but do not show improvements in physical health satisfaction. As different subjective satisfaction measures were recorded in each article, a clear conclusion spanning various articles cannot be accurately drawn yet. A meta-analysis of the results of case studies and a more comprehensive and long-term study are needed to determine if WELL upholds its premise and goals and whether it is an effective investment