From Practice to Policy to Practice

Recent molecular dynamics simulation results have increased conceptual understanding of the grazing and the ploughing friction at elevated temperatures, particularly near the substrate's melting point. In this commentary we address a major constraint concerning its experimental verification

Atomistic aspects of ductile responses of cubic silicon carbide during nanometric cutting

Cubic silicon carbide (SiC) is an extremely hard and brittle material having unique blend of material properties which makes it suitable candidate for microelectromechanical systems and nanoelectromechanical systems applications. Although, SiC can be machined in ductile regime at nanoscale through single-point diamond turning process, the root cause of the ductile response of SiC has not been understood yet which impedes significant exploitation of this ceramic material. In this paper, molecular dynamics simulation has been carried out to investigate the atomistic aspects of ductile response of SiC during nanometric cutting process. Simulation results show that cubic SiC undergoes sp3-sp2 order-disorder transition resulting in the formation of SiC-graphene-like substance with a growth rate dependent on the cutting conditions. The disorder transition of SiC causes the ductile response during its nanometric cutting operations. It was further found out that the continuous abrasive action between the diamond tool and SiC causes simultaneous sp3-sp2 order-disorder transition of diamond tool which results in graphitization of diamond and consequent tool wear

An Approach for Minimizing Spurious Errors in Testing ADA Tasking Programs

We propose an approach for detecting deadlocks and race conditions in Ada tasking software. It is based on an extension to Petri net-based techniques, where a concurrent program is modeled as a Petri net and a reachability graph is then derived and analyzed for desired information. In this approach, Predicate-Action subnets representing Ada programming constructs are described, where predicates and actions are attached to transitions. Predicates are those found in decision statements. Actions involve updating the status of the variables that affect the tasking behavior of the program and updating the Read and Write sets of shared variables. The shared variables are those occurring in sections of the program, called concurrency zones, related to the transitions. Modeling of a tasking program is accomplished by using the basic subnets as building blocks in translating only tasking-related statements and connecting them to produce the total Predicate-Action net model augmented with sets of shared variables. An augmented reachability graph is then derived by executing the net model. Deadlocks and race conditions are detected by searching the nodes of this graph. The main advantage offered by this approach is that the Predicate-Action extension of the net leads to pruning infeasible paths in the reachability graph and, thus, reducing the spurious error reports encountered in previous approaches. Also, this approach enables a partial handling of loops in a practical way. Implementation issues are also discussed in the paper

Opinion Change or Differential Turnout: Changing Opinions on the Austin Police Department in a Budget Feedback Process

In 2020 the tragic murder of George Floyd at the hands of law enforcement ignited and intensified nationwide protests, demanding changes in police funding and allocation. This happened during a budgeting feedback exercise where residents of Austin, Texas were invited to share opinions on the budgets of various city service areas, including the Police Department, on an online platform designed by our team. Daily responses increased by a hundredfold and responses registered after the "exogenous shock" overwhelmingly advocated for reducing police funding. This opinion shift far exceeded what we observed in 14 other Participatory Budgeting elections on our Participatory Budgeting Platform, and can't be explained by shifts in the respondent demographics. Analysis of the results from an Austin budgetary feedback exercise in 2021 and a follow-up survey indicates that the opinion shift from 2020 persisted, with the opinion gap on police funding widening. We conclude that there was an actual change of opinion regarding police funding. This study not only sheds light on the enduring impact of the 2020 events and protests on public opinion, but also showcases the value of analysis of clustered opinions as a tool in the evaluation toolkit of survey organizers.Comment: This preprint is an extended version of a previously published conference paper: https://dl.acm.org/doi/10.1145/3551624.355529

Medical informatics in an undergraduate curriculum: a qualitative study

BACKGROUND: There is strong support for educating physicians in medical informatics, and the benefits of such education have been clearly identified. Despite this, North American medical schools do not routinely provide education in medical informatics. METHODS: We conducted a qualitative study to identify issues facing the introduction of medical informatics into an undergraduate medical curriculum. Nine key informants at the University of Toronto medical school were interviewed, and their responses were transcribed and analyzed to identify consistent themes. RESULTS: The field of medical informatics was not clearly understood by participants. There was, however, strong support for medical informatics education, and the benefits of such education were consistently identified. In the curriculum we examined, medical informatics education was delivered informally and inconsistently through mainly optional activities. Issues facing the introduction of medical informatics education included: an unclear understanding of the discipline; faculty and administrative detractors and, the dense nature of the existing undergraduate medical curriculum. CONCLUSIONS: The identified issues may present serious obstacles to the introduction of medical informatics education into an undergraduate medicine curriculum, and we present some possible strategies for addressing these issues

Statistical Modelling of Computer Systems: A Review

This paper briefly reviews the data dependent statistical methods useful for computer systems modelling. The techniques are classified according to their applicability toward comparison, tuning and design of computer systems. A review of publications dealing with statistical modeling of computer systems is presented and a comprehensive bibliography is included to provide a useful source of reference toward the present and potential applications of statistical methods for computer system modelling

Statistical Modelling of Computer Systems: A Survey

This paper briefly surveys the data dependent statistical methods useful for computer systems modelling. The techniques are classified according to their applicability toward comparison, tuning and design of computer systems. A review of papers dealing with statistical modelling of computer systems is presented and a comprehensive bibliography is included to provide a useful source of reference toward the present and potential applications of statistical methods for computer system modelling

STATISTICAL MODELLING OF COMPUTER SYSTEMS: A SURVEY

This paper briefly surveys the data dependent statistical methods useful for computer systems modelling. The techniques are classified according to their applicability toward comparison, tuning and design of computer systems. A review of papers dealing with statistical modelling of computer systems is presented and a comprehensive bibliography is included to provide a useful source of reference toward the present and potential applications of statistical methods for computer system modelling