Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations

The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was$0.057/km and for the flywheel system was $0.037/km

Mass-energy balance for an S-1C rocket exhaust cloud during static firing

Rocket exhaust cloud mass-energy balance measurements for Saturn S1-C static firin

Keck Imaging of the Globular Cluster Systems in the Early--type Galaxies NGC 1052 and NGC 7332

The presence of two globular cluster subpopulations in early-type galaxies is now the norm rather than the exception. Here we present two more examples for which the host galaxy appears to have undergone a recent merger. Using multi-colour Keck imaging of NGC 1052 and NGC 7332 we find evidence for a bimodal globular cluster colour distribution in both galaxies, with roughly equal numbers of blue and red globular clusters. The blue ones have similar colours to those in the Milky Way halo and are thus probably very old and metal-poor. If the red GC subpopulations are at least solar metallicity, then stellar population models indicate young ages. We discuss the origin of globular clusters within the framework of formation models. We conclude that recent merger events in these two galaxies have had little effect on their overall GC systems. We also derive globular cluster density profiles, global specific frequencies and in the case of NGC 1052, radial colour gradients and azimuthal distribution. In general these globular cluster properties are normal for early-type galaxies.Comment: 11 pages, Latex, 15 figures, 2 tables, accepted by MNRA

“It gave me a much more personal connection”: Student generated podcasting and assessment in teacher education

This paper reports on a qualitative case study of an online initial teacher education class in New Zealand, exploring the potential of student-generated podcasts as a form of interactive formative assessment. Findings from interviews with teaching staff indicate that podcasting was useful for supporting multimodal learning valuing student voice and reflections. Podcasting enhanced the affective and relational connections in the online class, and empowered students to develop technical skills and confidence relevant in their teaching careers. As such, this study positions educators as future makers and as leaders in a climate of change. We suggest implications for student-generated podcasts in similar contexts

Contracts (Supplementary Cases): 2019-20

Course code: 1010.4https://digitalcommons.osgoode.yorku.ca/casebooks/1110/thumbnail.jp

Imagine There\u27s No Country : Statelessness as Persecution in Light of \u3cem\u3eHaile II\u3c/em\u3e

https://digitalcommons.cedarville.edu/volleyball_gallery/1012/thumbnail.jp