New York Prophecies: The Imaginary Future of Artificial Intelligence

The conflicts which have erupted over hacking, cracking and filesharing offer a stepping-stone for rethinking the involvement of users in innovation processes. As technical design processes invariably proceed in the shadow of established relations of social power, we can expect them to encompass conflicts over what constitutes the creative use of technology versus its misuse. The figure of the misuser calls attention to the importance of antagonistic relations in the mutual shaping of technology and society. Constructivist STS research has been criticised for neglecting the importance of antagonistic relations in favour of an emphasis on the limitless mutability of human/machine hybrids. The transformative effects of innovation processes on interests and subjectivities cannot be denied. But the induction of such transformations might be interpreted as a method through which struggles are conducted. This dynamic is particularly forthcoming in the case of filesharing, where users innovate precisely in order to overthrow the material practices upon which intellectual property law is founded. It is the intervention of law enforcement agencies in the process of drawing the line between users and misusers that makes the presence of an antagonistic relation manifest.     

Hydrogen-induced cold cracking in heat-affected zone of low-carbon high-strength steel

The Y-groove cracking test by submerged arc welding was employed to study the susceptibility of a low-carbon high-strength steel to hydrogen-induced cold cracking (HICC). The morphology of hydrogen cracks was observed using an electron probe microscope. The results showed that the heat-affected zone (HAZ) has a higher susceptibility to HICC than the weld metal and that increasing heat input can improve the HICC resistance of the weldment. The intergranular microcracking is the main HICC mode at the lowest heat input condition, accompanied with some transgranular microcracks attached to complex inclusions. In combination with phase transformation behaviour in sub-zones, the effect of the phase transformation sequence is proposed to try to illustrate the fact that the fine-grained HAZ has higher probability of hydrogen cracking than the coarse-grained HAZ owing to the occurrence of hydrogen enrichment in the fine-grained HAZ after the transformation.     

Enhanced resistance to weld cracking by strain-induced rapid solidification during linear friction welding

A study of weld cracking resistance during linear friction joining of a difficult-to-weld nickel-based superalloy was performed by Gleeble thermomechanical simulation coupled with an extensive microstructural analysis. It was found that crack-free welds produced by the supposedly solid-state joining technique of linear friction welding is not due to preclusion of grain boundary liquation as has been commonly assumed and reported. Instead, resistance to cracking can be related to a reduction in liquid stability by the imposed compressive strain during welding.     

Discontinuous cracking of TiN films on a steel substrate induced by an adhesive interlayer

ABSTRACT

The basic mechanisms governing the process of cracking of single-layer brittle films have been extensively explored through both simulations and experiments. However, the role that an adhesive interlayer plays in the cracking of the overlying brittle film remains unclear. By performing three-point bending experiments, we observed that the insertion of a 100?nm thick Ti interlayer changed the cracking behaviour of TiN films from a continuous pattern to a discontinuous pattern. The slight change in the microstructure of the film and the increase in film thickness arising from the addition of the Ti interlayer are unlikely to cause the observed cracking morphology. The combination of the different interface between the Ti and the steel substrate and the fracture of the Ti interlayer are responsible for the transition in the TiN film cracking morphologies.     

Failure mechanism in porous materials under compression: crackling noise in mesoporous SiO2

The failure mechanism of porous materials under uniaxial stress has been investigated experimentally. Microporous SiO₂, Vycor, has been subjected to slowly increasing compressive uniaxial stress with stress rates between 0.2 and 12.2?kPa/s. With increasing stress the strain changes stepwise with acoustic emission correlated with each volume collapse. The acoustic emission followed the characteristics of ‘crackling noise’ with a power law distribution over an exceptionally large interval of 6 decades at the slowest stress rate. The power law exponent is ?1.39. Possible applications in mining industry and others are discussed.     

Do capuchin monkeys use weight to select hammer tools?

The extent to which tool-using animals take into account the properties of the tool is little explored. The use of percussors to crack open encapsulated fruit is a complex form of tool use, the choice of an adequate tool being a critical aspect in success. Several properties (e.g., material, resistance, friability, shape and weight) affect the suitability of an object to open a hard-shelled nut, with weight being amongst the most important factors. In general, heavier tools require fewer strikes to crack open a nut.