Worcester Polytechnic Institute

About: Worcester Polytechnic Institute is a education organization based out in Worcester, Massachusetts, United States. It is known for research contribution in the topics: Computer science & Population. The organization has 6270 authors who have published 12704 publications receiving 332081 citations. The organization is also known as: WPI.

Incorporating Rich Features into Deep Knowledge Tracing

Abstract: Knowledge Tracing aims to model student knowledge by predicting the correctness of each next item as students work through an assignment. Through recent developments in deep learning, Deep Knowledge Tracing (DKT) was explored as a method to improve upon traditional methods. Thus far, the DKT model has only considered the knowledge components and correctness as input, neglecting the other important features collected by computer-based learning platforms. This paper seeks to further improve upon DKT by incorporating more problem-level features. With this higher dimensional input, an adaption to the original DKT model structure is also proposed to convert the input into a low dimensional feature vector. Our results show that this adapted DKT model can effectively improve accuracy.

Verifying cross-cutting features as open systems

Abstract: Feature-oriented software designs capture many interesting notions of cross-cutting, and offer a powerful method for building product-line architectures. Each cross-cutting feature is an independent module that fundamentally yields an open system from a verification perspective. We describe desiderata for verifying such modules through model checking and find that existing work on the verification of open systems fails to address most of the concerns that arise from feature-oriented systems. We therefore provide a new methodology for verifying such systems. To validate this new methodology, we have implemented it and applied it to a suite of modules that exhibit feature interaction problems. Our model checker was able to automatically locate ten problems previously found through a laborious simulation-based effort.

Roadmap for enhanced languages and methods to aid verification

Abstract: This roadmap describes ways that researchers in four areas---specification languages, program generation, correctness by construction, and programming languages---might help further the goal of verified software. It also describes what advances the "verified software" grand challenge might anticipate or demand from work in these areas. That is, the roadmap is intended to help foster collaboration between the grand challenge and these research areas.A common goal for research in these areas is to establish language designs and tool architectures that would allow multiple annotations and tools to be used on a single program. In the long term, researchers could try to unify these annotations and integrate such tools.

Smectic ordering in liquid-crystal-aerosil dispersions. I. X-ray scattering.

Abstract: Comprehensive x-ray scattering studies have characterized the smectic ordering of octylcyanobiphenyl (8CB) confined in the hydrogen-bonded silica gels formed by aerosil dispersions. For all densities of aerosil and all measurement temperatures, the correlations remain short range, demonstrating that the disorder imposed by the gels destroys the nematic (N) to smectic-A (SmA) transition. The smectic correlation function contains two distinct contributions. The first has a form identical to that describing the critical thermal fluctuations in pure 8CB near the N-SmA transition, and this term displays a temperature dependence at high temperatures similar to that of the pure liquid crystal. The second term, which is negligible at high temperatures but dominates at low temperatures, has a shape given by the thermal term squared and describes the static fluctuations due to random fields induced by confinement in the gel. The correlation lengths appearing in the thermal and disorder terms are the same and show a strong variation with gel density at low temperatures. The temperature dependence of the amplitude of the static fluctuations further suggests that nematic susceptibility becomes suppressed with increasing quenched disorder. The results overall are well described by a mapping of the liquid-crystal-aerosil system onto a three-dimensional XY model in a random field with disorder strength varying linearly with the aerosil density.