Wheel of fortune : the re-gifting of art-life

My essay for the Waterwheel project entitled “Wheel of fortune: re-gifting art-life” will examine the Waterwheel project from the point of view of gift economies and discuss the benefits and sustainability of this model for collaboration and cooperation. This essay builds upon the history of gift economies, focusing on the gift as a mode of collaboration and platform for exchange. The alchemical notion of the gift that Gordon Matta- Clark café “FOOD” offers will be discussed as a precursor to the transformation of relations evident in the workshop series organized by Erin Manning and Brian Massumi. In particular, this essay will emphasize the way transformation has been used to rethink the gift as modeling of collaboration and re-imagining of the ties between research creation and social activism. From these discussions the context and ethos by which to understand the aims of the Waterwheel project will be addressed.

Robust fault-tolerant leader-follower control of four-wheel-steering mobile robots using terminal sliding mode

This paper addresses the actuator failure compensation problem of non-linear fourwheel-steering mobile robots based on vehicle kinematics, undergoing both known and unknown failures causing degenerated steering performance or wheels stuck at some observable angles. Terminal sliding mode control technique is used to guarantee the tracking stability infinite time with the presence of actuator fault. Simulation results are given to illustrate the effectiveness of the proposed control scheme. © Institution of Engineers Australia 2012.

A corrosion inhibition study of steel grinding balls in an oxygen and alkaline environment

The corrosion of steel grinding balls is a major recurrent cost for mill operators concerned with the production gold. Subsequently, the use of corrosion inhibitors in production fluids, which is typically at pH >9, is an attractive and economical option. This study reports on the corrosion wear of steel grinding balls under alkaline/oxygen conditions and in presence of cyanide. A fundamental study on the influence of several inorganic-based inhibitors (i.e., nitrite, chromate, silicate, hexametaphosphate) on the corrosion rate of carbon steel was undertaken. Subsequently, the corrosion performances of various inhibitors were evaluated in stirred vessels. Corrosion rates were determined via mass loss and electrochemical methods (i.e., linear polarisation, Tafel). It was observed that inhibitors based upon chromate provide superior protection under the conditions investigated in this study. In lime treated, high chloride waters, chromate gave over 80% protection at levels of 10 100 ppm with no evidence of pitting.

Are voluntary wheel running and open-field behavior correlated in mice? Different answers from comparative and artificial selection approaches

Voluntary wheel running and open-field behavior are probably the two most widely used measures of locomotion in laboratory rodents. We tested whether these two behaviors are correlated in mice using two approaches: the phylogenetic comparative method using inbred strains of mice and an ongoing artificial selection experiment on voluntary wheel running. After taking into account the measurement error and phylogenetic relationships among inbred strains, we obtained a significant positive correlation between distance run on wheels and distance moved in the open-field for both sexes. Thigmotaxis was negatively correlated with distance run on wheels in females but not in males. By contrast, mice from four replicate lines bred for high wheel running did not differ in either distance covered or thigmotaxis in the open field as compared with mice from four non-selected control lines. Overall, results obtained in the selection experiment were generally opposite to those observed among inbred strains. Possible reasons for this discrepancy are discussed.

Limited effect of fly-wheel and spinal mobilization exercise countermeasures on lumbar spine deconditioning during 90 d bed-rest in the Toulouse LTBR study

We examined the effect of high-load fly-wheel (targeting the lower-limb musculature and concurrent loading of the spine via shoulder restraints) and spinal movement countermeasures against lumbar spine muscle atrophy, disc and spinal morphology changes and trunk isokinetic torque loss during prolonged bed-rest. Twenty-four male subjects underwent 90 d head-down tilt bed-rest and performed either fly-wheel (FW) exercises every three days, spinal movement exercises in lying five times daily (SpMob), or no exercise (Ctrl). There was no significant impact of countermeasures on losses of isokinetic trunk flexion/extension (p≥0.65). Muscle volume change by day-89 of bed-rest in the psoas, iliacus, lumbar erector spinae, lumbar multifidus and quadratus lumborum, as measured via magnetic resonance imaging (MRI), was statistically similar in all three groups (p≥0.33). No significant effect on MRI-measures of lumbar intervertebral disc volume, spinal length and lordosis (p≥0.09) were seen either, but there was some impact (p≤0.048) on axial plane disc dimensions (greater reduction than in Ctrl) and disc height (greater increases than in Ctrl). MRI-data from subjects measured 13 and 90-days after bed-rest showed partial recovery of the spinal extensor musculature by day-13 after bed-rest with this process complete by day-90. Some changes in lumbar spine and disc morphology parameters were still persistent 90-days after bed-rest. The present results indicate that the countermeasures tested were not optimal to maintain integrity of the spine and trunk musculature during bed rest. © 2011 Elsevier Ltd.

On the production of randomly-oriented recrystallization nuclei for selective growth experiments

The ideal starting condition for selective growth experiments is one having a layer of randomly-oriented nuclei adjacent to a matrix with negligible orientational variation but sufficient stored energy to promote growth. In practice, cutting or deformation processes are used in an attempt to approximate these ideal conditions, but the degree to which this is achieved has not been rigorously quantified. In this work, Fe-3wt%Si single crystals were cut or deformed using six different processes. The variation in texture with distance from the cut or deformed surface was measured using electron backscatter diffraction (EBSD) in a field emission gun scanning electron microscope (FEG-SEM) in order to assess the ability of each process to create conditions suitable for selective growth experiments. While grooving with a machine tool produced the best spread of orientations at the cut surface, the suitability of this process is diminished by the presence of a differently-textured deformed layer between the cut surface and the single crystal matrix. Grinding produced a less ideal distribution of orientations at the cut surface, but the presence of these orientations in a very thin layer adjacent to the matrix makes this process preferable for preparing crystals for selective growth experiments, provided the results are corrected for the deviation in the distribution of nuclei orientations from a random distribution.

The effect of repeated pulses of light at the same time on period responses of the rat circadian pacemaker.

A consequence of simple velocity-based models is that, in response to light pulses, the circadian period should adjust inversely to phase. In addition, because of the interaction of circadian period and phase response, earlier circadian period changes should modify later circadian period changes. The literature contains few mentions of response curves of circadian period responses following light pulses. Rats were exposed to four pulses of light (60 minutes, 1000 lux) at the same circadian time, a minimum of 26 days apart; we assessed period responses and possible bias in the period-response curve. Modulation of circadian period following light-induced phase responses was examined by assessing the period of running wheel activity onset. Phase and circadian period were not consistently found to share an inverse relationship. Moreover, biases in initial period tended to be increased by the experimental protocol regardless of circadian time of pulse. Rats with a short initial (highvelocity) period had a lengthened period, while rats with a long initial period (low velocity) tended to have a reduce period. However, rats with a long initial period were phase delay biased, not phase advance biased. These results do not support a simple velocity model of the pacemaker.

Motorcycle ownership and injury in China

Background. China has made tremendous progress in its economic development in the past two decades. Accompanying this economic development has been an evident shift in the modes of transport, from walking and cycling to the use of motorcycles and, increasingly, four-wheel vehicles. Such changes are likely to have also produced changes in the patterns and numbers of road traffic injuries, including increases in motorcycle injuries. However, such changes have not been well documented. The work described in this paper sought, therefore, to document the changes in motorcycle ownership, motorcyclist mortality and injury rates in China since 1987.
Methods. National traffic ownership and injury data from 1987 to 2001 were obtained from the National Bureau for Traffic Administration. Additionally, traffic ownership and injury records from 1997 to 2001 were collected from local police offices from 20 counties in Guangxi Region. Population data were obtained from the national and county statistics bureaus. Motorcycle ownership, fatality and injury trends over time were calculated.
Results. Nationally, motorcycles accounted for 23.4% of all registered motor vehicles in 1987, increasing to 63.2% in 2001. Motorcyclist fatalities and injuries increased 5.5-fold and 9.3-fold, respectively, between 1987 and 2001. In 1987, 7.5% of all traffic fatalities and 8.8% of all traffic injuries were sustained by motorcyclists, with the corresponding proportions increasing to 18.9% and 22.8%, respectively, in 2001. The changing proportions of both traffic fatalities and injuries sustained by motorcyclists were positively correlated with the change in the proportion of motorcycles among all motor vehicles. In the 20 counties in Guangxi, motorcyclist fatality and injury rates also increased between 1997 and 2001. Moreover, these rates were considerably higher than the national rates.
Conclusions. Motorcyclist injury in China is a serious public health problem. Motorcyclist fatalities and injuries are likely to continue to increase unless appropriate intervention programmes are implemented.

Simulating autonomous robot teams with Microsoft robotics studio

This paper presents an application of Microsoft Robotics Studio (MSRS) in which a team of six four wheel drive, ground based robots explore and map simulated terrain. The user has the ability to modify the terrain and assign destination objectives to the team while the simulation is running. The terrain is initially generated using a gray scale image, in which the intensity of each pixel in the image gives an altitude datum. The robots start with no knowledge of their surroundings, and map the terrain as they attempt to reach user-defined target objectives. The mapping process simulates the use of common sensory hardware to determine datum points, including provision for field of view, detection range, and measurement accuracy. If traversal of a mapped area is indicated by the users’ targeting commands, path planning heuristics developed for MSRS by the author in earlier work are used to determine an efficient series of waypoints to reach the objective. Mutability of terrain is also explored- the user is able to modify the terrain without stopping the simulation. This forces the robots to adapt to changing environmental conditions, and permits analysis of the robustness of mapping algorithms used when faced with a changing world.

Rote movie

"On the voice over de Bruyn places himself behind the wheel of a car, an appropriate metaphor for his expatriate driven reflections on his feelings of exile, distance and loneliness. Necessarily unintelligent memories highlight habitual subjectivity of "walking through a landscape alone", "gypsy", "victim". Images of roadsigns, cars, billboards, the passing landscape; elegantly simple rotoscope (by rote?) drawings, recopied and texturally manipulated filmic images; the inevitability of the repetition of leader. A tired, yearning, moving film." http://www.innersense.com.au/mif/debruyn_films.html