Dear Wife : the Civil War letters of Chester K. Leach

Occasional paper (University of Vermont. Center for Research on Vermont) ; no. 20

Wear and Friction Modeling on Lifeboat Launch Systems

The RNLI provides search and rescue cover along the UK and RoI coast using a variety of lifeboats and launch techniques. In locations where there is no natural harbour it is necessary to use a slipway to launch the lifeboat into the sea. Lifeboat slipway stations consist of an initial section where the boat is held on rollers followed by an inclined keelway lined with low friction composite materials, the lifeboat is released from the top of the slipway and proceeds under its own weight into the water. The lifeboat is later recovered using a winch line. It is common to manually apply grease to the composite slipway lining before each launch and recovery in order to ensure sufficiently low friction for successful operation. With the introduction of the Tamar class lifeboat it is necessary to upgrade existing boathouses and standardise slipway operational procedures to ensure consistent operation. The higher contact pressures associated with the new lifeboat have led to issues of high friction and wear on the composite slipway linings and the manual application of grease to reduce friction is to be restricted due to environmental impact and cost factors. This paper presents a multidisciplinary approach to modelling slipway panel wear and friction using tribometer testing in conjunction with finite element analysis and slipway condition surveys to incorporate common real-world effects such as panel misalignments. Finally, it is shown that a freshwater lubrication system is effective, reducing cost and environmental impacts while maintaining good friction and wear performance

Dust storms on Mars: Considerations and simulations

Aeolian processes are important in modifying the surface of Mars at present, and appear to have been significant in the geological past. Aeolian activity includes local and global dust storms, the formation of erosional features such as yardangs and depositional features such as sand dunes, and the erosion of rock and soil. As a means of understanding aeolian processes on Mars, an investigation is in progress that includes laboratory simulations, field studies of earth analogs, and interpretation of spacecraft data. This report describes the Martian Surface Wind Tunnel, an experimental facility established at NASA-Ames Research Center, and presents some results of the general investigation. Experiments dealing with wind speeds and other conditions required for the initiation of particle movement on Mars are described and considerations are given to the resulting effectiveness of aeolian erosion

‘We kind of try to merge our own experience with the objectivity of the criteria’: The role of connoisseurship and tacit practice in undergraduate fine art assessment

This article explores connoisseurship in the context of fine art undergraduate assessment practice. I interviewed twelve fine art lecturers in order to explore and unpack the concept of connoisseurship in relation to subjectivity, objectivity and tacit practice. Building on the work of Bourdieu (1973, 1977, 1986) and Shay (2003, 2005), both of whom problematize the view that subjectivity and objectivity are binary opposites, my research illustrates the ways that connoisseurship is underpinned by informed professional judgements located in communities of practice. Within this particular conception of connoisseurship, the lecturers’ expertise is co-constituted in communities of assessors through participation and engagement. Standards reside in communities of practice

Aeolian processes aboard a space station: Saltation and particle trajectory analysis

The Carousel wind tunnel (CWT) proposed to study aeolian processes aboard a space station consists of two concentric rotating drums. The space between the two drums comprises the wind tunnel test section. Differential rates of rotation of the two drums would provide a wind velocity with respect to either drum surface. Preliminary results of measured velocity profiles made in a CWT prototype indicate that the wall bounded boundary layer profiles are suitable to simulate flat plate turbulent boundary layer flow. The two dimensional flat plate Cartesian coordinate equations of motion of a particle moving through the air are explained. In order to assess the suitability of CWT in the analysis of the trajectories of windblown particles, a series of calculations were conducted comparing cases for gravity with those of zero gravity. Results from the calculations demonstrate that a wind tunnel of the carousel design could be fabricted to operate in a space station environment and that experiments could be conducted which would yield significant results contributing to the understanding of the physics of particle dynamics

Becoming Human? Ableism and Control in \u3cem\u3eDetroit: Become Human\u3c/em\u3e and the Implications for Human-Machine Communication

In human-machine communication (HMC), machines are communicative subjects in the creation of meaning. The Computers are Social Actors and constructivist approaches to HMC postulate that humans communicate with machines as if they were people. From this perspective, communication is understood as heavily scripted where humans mindlessly apply human-to-human scripts in HMC. We argue that a critical approach to communication scripts reveals how humans may rely on ableism as a means of sense-making in their relationships with machines. Using the choose-your-own-adventure game Detroit: Become Human as a case study, we demonstrate (a) how ableist communication scripts render machines as both less-than-human and superhuman and (b) how such scripts manifest in control and cyborg anxiety. We conclude with theoretical and design implications for rescripting ableist communication scripts

How to Select Pictures

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