Learning Weak Constraints in Answer Set Programming

This paper contributes to the area of inductive logic programming by presenting a new learning framework that allows the learning of weak constraints in Answer Set Programming (ASP). The framework, called Learning from Ordered Answer Sets, generalises our previous work on learning ASP programs without weak constraints, by considering a new notion of examples as ordered pairs of partial answer sets that exemplify which answer sets of a learned hypothesis (together with a given background knowledge) are preferred to others. In this new learning task inductive solutions are searched within a hypothesis space of normal rules, choice rules, and hard and weak constraints. We propose a new algorithm, ILASP2, which is sound and complete with respect to our new learning framework. We investigate its applicability to learning preferences in an interview scheduling problem and also demonstrate that when restricted to the task of learning ASP programs without weak constraints, ILASP2 can be much more efficient than our previously proposed system.Comment: To appear in Theory and Practice of Logic Programming (TPLP), Proceedings of ICLP 201

Experimental and analytical assessment of prestressed concrete bridges damaged by overheight vehicle impact

Due to frequent accidental damage to prestressed concrete (P/C) bridges caused by impact from overheight vehicles, a project was initiated to evaluate the strength and load distribution characteristics of damaged P/C bridges. A comprehensive literature review was conducted. It was concluded that only a few references pertain to the assessment and repair of damaged P/C beams;Structural testing of two bridges was conducted in the field. The first bridge tested was the westbound (WB) I-680 bridge in Beebeetown, Iowa. This bridge had significant damage to the first and second beams. The second bridge, the adjacent eastbound (EB) structure, was used as a reference. The testing concluded that load redistribution was occurring in the WB bridge. Subsequent to these tests, the damaged beams in the WB bridge were replaced and the bridge retested. The repaired WB bridge behaved like the undamaged EB bridge indicating that the beam replacement restored the original live load distribution patterns;Four isolated P/C beams were tested, two removed from the Beebeetown bridge and two from a large-scale bridge model tested by others. For the Beebeetown beams, Beam 1W was tested in an as-removed condition and Beam 2W was retrofit with carbon fiber reinforced polymer (CFRP) longitudinal plates and transverse stirrups. Beam 2W was 12% stronger than Beam 1W. Beams 1 and 2 from the bridge model were also tested. Beam 1 was not damaged while Beam 2 was damaged and repaired, again using CFRP plates. The retrofit beam attained a capacity greater than a theoretically undamaged beam prior to plate debonding;Analytical models were created for the undamaged and damaged center spans of the WB bridge; stiffened plate and grillage models were used. Both models were accurate at predicting the deflections in the tested bridges and should be similarly accurate in modeling other P/C bridges. The moment fractions per beam were computed using both models. The damaged model indicates a significant decrease in moment in the damaged beams and a redistribution of load to the adjacent curb and rail as well as to the undamaged beam lines

Quantitative Literacy and High School Mathematics : The Evolution of a Collaboratively Constructed Course and Its Impact on Students\u27 Attitudes and Numeracy

This study describes a practitioner action research project in which I co-constructed a high school mathematics elective course with my students. The focus of the course was on developing students’ quantitative literacy. I examined the impact of the coconstruction process on the evolution of the course, analyzed how the course influenced students’ quantitative literacy and attitudes about mathematics, and reflected on some of the lessons I learned about making mathematics more relevant for my students. This study fills a gap in the literature by describing the impact of a quantitative literacy course at the high school level and by documenting the effect of co-construction on an entire course. In order to answer my research questions, I relied on qualitative data gathered from surveys, questionnaires, classroom assessments, transcriptions of classroom discussions, field notes, and my own research journal. The findings of this study highlight some of the complexities involved in the co-construction process, the impact of coconstruction on students’ interest, and some key themes related to teaching for quantitative literacy

The Tension Between the Need and Exploitation of Migrant Workers: Using MSAWPA\u27s Legislative Intent to Find a Balanced Remedy

This Comment concludes that the recent Maine federal district cases represent an irreconcilable spike in a national and international trend to afford more protection to a vulnerable class whose resources are the object of urgent demand. However, the search for a proper remedial weight in the balance between migrant worker protection and the provision of competitive farm labor is not a new problem

The 2019 European Elections: Something old, something new, something borrowed, and something green

© 2020 Società Italiana di Scienza Politica. In the aftermath of a European Parliament (EP) election, there are normally two prominent aspects that receive attention by scholars and experts: the turnout rate and whether the Second Order Election (SOE) model proposed by Reif and Schmitt (1980) still applies. That model is based on the idea that, because EP elections do not themselves provide enough stimulus as to replace the concernsnormally present at national elections, the outcomes of EP elections in any participating country manifest themselves as a sort of distorted mirror of national (Parliamentary) elections in that country. The mirror is distorted because those national concerns are modified, not so much by the concerns arising from the European context in which EP elections are held as simply by the fact that EP elections are not national elections. In particular, at EP elections, national executive power is not at stake. The same party or parties will rule in each country after an EP election as ruled there before