Recent Observations of Plasma and Alfvenic Wave Energy Injection at the Base of the Fast Solar Wind

We take stock of recent observations that identify the episodic plasma heating and injection of Alfvenic energy at the base of fast solar wind (in coronal holes). The plasma heating is associated with the occurrence of chromospheric spicules that leave the lower solar atmosphere at speeds of order 100km/s, the hotter coronal counterpart of the spicule emits radiation characteristic of root heating that rapidly reaches temperatures of the order of 1MK. Furthermore, the same spicules and their coronal counterparts ("Propagating Coronal Disturbances"; PCD) exhibit large amplitude, high speed, Alfvenic (transverse) motion of sufficient energy content to accelerate the material to high speeds. We propose that these (disjointed) heating and accelerating components form a one-two punch to supply, and then accelerate, the fast solar wind. We consider some compositional constraints on this concept, extend the premise to the slow solar wind, and identify future avenues of exploration.Comment: 12 pages, 9 figures - accepted to appear in Space Science Review

Active engagement with assessment and feedback can improve group-work outcomes and boost student confidence

This study involves evaluation of a novel iterative group-based learning task developed to enable students to actively engage with assessment and feedback in order to improve the quality of their written work. The students were all in the final semester of their final year of study and enrolled on either BSc Zoology or BSc Marine and Freshwater Biology at a mainstream UK university, but the findings of this research can be generalised to a wider student body. The main findings are that in a group work context, individual students can use provided assessment criteria to accurately assess the work produced by their group and that their ability to produce and recognise work of a higher quality improves as a result of a social dialogue around self/peer assessment and self/tutor generated feedback. The study also reveals that producing poorer work over-assess and those achieving the highest marks under-assess. Over-assessing students focus to a greater extent upon the superficial deficiencies in their work, whereas under assessing students are more likely to focus on more significant issues. High-achieving under-assessing students lack confidence in their own abilities, but believe feedback provides a confidence boost

Tactile sensing means for prosthetic limbs

An improved prosthetic device characterized by a frame and a socket for mounting on the stump of a truncated human appendage is described. Flexible digits extend from the distal end and transducers located within the digits act as sensing devices for detecting tactile stimuli. The transducers are connected through a power circuit with a slave unit supported by a strap and fixed to the stump. The tactile stimuli detected at the sensing devices are reproduced and applied to the skin of the appendage in order to stimulate the sensory organs located therein

The Library's Place in the Junior College

published or submitted for publicatio

Estimates of primary and secondary particle doses behind aluminum and polyethylene slabs due to incident solar-flare and Van Allen belt protons

Primary and secondary particle radiation doses shielded from solar flare and Van Allen belt protons by aluminum and polyethylene slab

Bonding titanium to Rene 41 alloy

Pair of intermediate materials joined by electron beam welding method welds titanium to Rene 41 alloy. Bond is necessary for combining into one structure high strength-to-density ratio titanium fan blades and temperature resistant nickel-base alloy turbine-buckets in VTOL aircraft lift-fan rotor

The Place of Theology in the Life of the Church

Lecture presented at Lutheran Theological Seminary, Saskatoon, Fall 1995

Correlation of the orbach relaxation coefficient with optical linewidths- laf3-er3 plus

Correlation of Orbach coefficient of spin-lattice relaxation with optical transition linewidths for trivalent erbium in lanthanum fluorid

Multivariate Density Estimation and Visualization

This chapter examines the use of flexible methods to approximate an unknown density function, and techniques appropriate for visualization of densities in up to four dimensions. The statistical analysis of data is a multilayered endeavor. Data must be carefully examined and cleaned to avoid spurious findings. A preliminary examination of data by graphical means is useful for this purpose. Graphical exploration of data was popularized by Tukey (1977) in his book on exploratory data analysis (EDA). Modern data mining packages also include an array of graphical tools such as the histogram, which is the simplest example of a density estimator. Exploring data is particularly challenging when the sample size is massive or if the number of variables exceeds a handful. In either situation, the use of nonparametric density estimation can aid in the fundamental goal of understanding the important features hidden in the data. In the following sections, the algorithms and theory of nonparametric density estimation will be described, as well as descriptions of the visualization of multivariate data and density estimates. For simplicity, the discussion will assume the data and functions are continuous. Extensions to discrete and mixed data are straightforward. --