Using latent-semantic analysis and network analysis for monitoring conceptual development

This paper describes and evaluates CONSPECT (from concept inspection), an application that analyses states in a learner’s conceptual development. It was designed to help online learners and their tutors monitor conceptual development and also to help reduce the workload of tutors monitoring a learner’s conceptual development. CONSPECT combines two technologies - Latent Semantic Analysis (LSA) and Network Analysis (NA) into a technique called Meaningful Interaction Analysis (MIA). LSA analyses the meaning in the textual digital traces left behind by learners in their learning journey; NA provides the analytic instrument to investigate (visually) the semantic structures identified by LSA. This paper describes the validation activities undertaken to show how well LSA matches first year medical students in 1) grouping similar concepts and 2) annotating text

Systematic errors in diffusion coefficients from long-time molecular dynamics simulations at constant pressure

In molecular dynamics simulations under periodic boundary conditions, particle positions are typically wrapped into a reference box. For diffusion coefficient calculations using the Einstein relation, the particle positions need to be unwrapped. Here, we show that a widely used heuristic unwrapping scheme is not suitable for long simulations at constant pressure. Improper accounting for box-volume fluctuations creates, at long times, unphysical trajectories and, in turn, grossly exaggerated diffusion coefficients. We propose an alternative unwrapping scheme that resolves this issue. At each time step, we add the minimal displacement vector according to periodic boundary conditions for the instantaneous box geometry. Here and in a companion paper [J. Chem. Phys. XXX, YYYYY (2020)], we apply the new unwrapping scheme to extensive molecular dynamics and Brownian dynamics simulation data. We provide practitioners with a formula to assess if and by how much earlier results might have been affected by the widely used heuristic unwrapping scheme.Comment: 6 pages, 5 figures. The following article has been accepted for publication at The Journal of Chemical Physic

An exploration of two couples workshop approaches: Getting the Love You Want by Imago Relationships International and The Art and Science of Love by The Gottman Institute

The purpose of this project is to examine, compare, and evaluate two differing approaches to couples’ workshops. Chapter 1 will use one couple’s story to illustrate the epidemic of romantic relationship/marriage dissolution. Chapter 2, the literature review, will introduce two workshop approaches by Harville Hendrix and John Gottman. This chapter presents literature that supports the workshops and highlights couples’ therapy research. Chapter 3 will review each workshop separately with respect to their goals, structure, and how they express underlying ideas. Also, a comparison and evaluation will be provided for both. Chapter 4 will follow with a summative evaluation of my learning experiences as a person, student, and professional. Finally, chapter 5 will discuss the limitations of the workshops and will propose ideas for future analysis

Spherical Diffusion

Data defined on spherical domains occurs in various applications, such as surface modeling, omnidirectional imaging, and the analysis of keypoints in volumetric data. The theory of spherical signals lacks important concepts like the Gaussian function, which is permanently used in planar image processing. We propose a definition of a spherical Gaussian function as the Green\u27s function of the spherical diffusion process. This allows to introduce a linear scale space on the sphere. We apply this new filter to the smoothing of 3D object surfaces

Consistent Phase Estimation for Recovering Depth From Moiré Interferograms

Moiré interferometry is a common tool if depth estimation from a single image frame is desired. It uses the interference of periodic patterns to measure the topology of a given surface. The actual depth estimation relies on the consistent phase estimation from the interferogram. We show that this task can be simplified by estimating the image phase and the local image orientation simultaneously, followed by a processing step called orientation unwrapping which is introduced in this paper. We compare two methods for extracting image phase and orientation and present experimental results

Numerical simulation of destabilizing heterogeneous suspensions at vanishing Reynolds numbers

This work deals with the numerical investigation of destabilizing suspensions, which are governed by two basic processes: Clustering and sedimentation. After laying the foundation to an efficient numerical simulation based on the Stokesian Dynamics method, hydrodynamic clustering and clustering due to non-hydrodynamic interactions are investigated. It is shown that multi-particle simulations need parallelization and an efficient post-processing to yield reliable results within a reasonable time