The second data release from ESA's Gaia mission has revealed many ridge-like structures in the velocity distribution of the Milky Way. We show that these can arise naturally from winding transient spiral structure that is commonly seen in N -body simulations of disk galaxies. We construct test particle models of the winding spiral structure, and compare the resulting distribution of orbits with the observed twodimensional velocity distribution in the extended solar neighbourhood and with the distribution of rotational velocities over 8 kpc along the Sun-Galactic-centre-Galactic anti-centre line. We show that the ridges in these observations are well reproduced by the winding spiral model. Additionally, we demonstrate that the transient winding spiral potential can create a Hercules-like feature in the kinematics of the solar neighbourhood, either alone, or in combination with a long-slow bar potential.

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Background: Automated program repair and other bug-fixing approaches are gaining attention in the software engineering community. Automation shows promise in reducing bug fixing costs. However, many developers express reluctance about accepting machinegenerated patches into their codebases. Aims: To contribute to the scientific understanding and the empirical investigation of human trust and perception with regards to automation in software maintenance. Method: We design and conduct an eye-tracking study investigating how developers perceive trust as a function of code provenance (i.e., author or source). We systematically vary provenance while controlling for patch quality. Results: In our study of ten participants, overall visual code scanning and the distribution of attention differed across identical code patches labeled as human-vs. machine-written. Participants looked more at the source code for human-labeled patches and looked more at tests for machine-labeled patches. Participants judged human-labeled patches to have better readability and coding style. However, participants were more comfortable giving a critical task to an automated program repair tool. Conclusion: We find that there are significant differences in code review behavior based on trust as a function of patch provenance. Further, we find that important differences can be revealed by eye tracking. Our results may inform the subsequent design and analysis of automated repair techniques to increase developers' trust and, consequently, their deployment. CCS CONCEPTS • Software and its engineering → Software creation and management.

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Consulting for a startup company is an effective way for Master of Business Administration (MBA) students to learn about management consulting, and the ways and means of a startup company. This paper discusses the experience of an MBA startup project within the context of a core corporate finance course. The project requires the active engagement of several groups of stakeholders—MBA students, the university’s entrepreneurship incubator, a selection of startup companies, and the project’s academic collaborators. In line with the literature, we find that entrepreneurship education through student-startup collaboration contributes to the students’ entrepreneurial learning, and that the offering of an experiential learning course provides students with the opportunities to work with the external business community that yield positive benefits for students, startups, and the university. Our findings add to the experiential learning literature in business education and show that practice-based learning offers an effective learning experience for students whereby all stakeholders are exposed to various communities of practice that facilitate multiple streams of learning. We provide insights on experiential learning from the implementation of a “new” learning pedagogy for MBA students at an Asian institute of higher learning.

The shear localization phenomena during serrated chip formation in high speed orthogonal metal cutting process have been studied by using the explicit finite element analysis. A three dimensional computational model has been developed for analyzing dynamic thermomechanical deformations of a thermally softening viscoplastic workpiece material subjected to various tool cutting speeds and tool rake angles. The shear band characteristics such as temperature contour, effective plastic strain, effective plastic strain rate, propagating speed and orientation are investigated for each cases. Cutting forces can be estimated by this 3D model. The predictions of the finite element analysis are shown that above a critical high cutting speeds the secondary shear of the chip on rake surface appear to be a negligible effect which indicated the chip segments can be separate completely due to extensive shear in the primary shear zone; this phenomena agreed well with the experimental observations. The numerical model presented here can easily applied to study the oblique cutting process.