35 resultados para cutting ages
Resumo:
The artwork describes web as a network environment and a space where people are connected and as a result, it can reshape you as an interactive participant who is able to regenerate an object as a new form through a truly collaborative and cooperative interactions with others. The artwork has been created based on the research findings of characteristic of web: 1) Participatory (Slater 2002, p.536), 2) Communicational (Rheingold 1993), 3) Connected (Jordan 1999, 80), and 4) Stylising (Jordan 1999, 69). The artwork has conceptualised and visualised those characteristics of web based on principles of graphic design and visual communication.
Resumo:
Mining is the process of extracting mineral resources from the Earth for commercial value. It is an ancient human activity which can be traced back to Palaeolithic times (43 000 years ago), where for example the mineral hematite was mined to produce the red pigment ochre. The importance of many mined minerals is reflected in the names of the major milestones in human civilizations: the stone, copper, bronze, and iron ages. Much later coal provided the energy that was critical to the industrial revolution and still underpins modern society, creating 38% of world energy generation today. Ancient mines used human and later animal labor and broke rock using stone tools, heat, and water, and later iron tools. Today’s mines are heavily mechanized with large diesel and electrically powered vehicles, and rock is broken with explosives or rock cutting machines.
Resumo:
In this paper, two ideal formation models of serrated chips, the symmetric formation model and the unilateral right-angle formation model, have been established for the first time. Based on the ideal models and related adiabatic shear theory of serrated chip formation, the theoretical relationship among average tooth pitch, average tooth height and chip thickness are obtained. Further, the theoretical relation of the passivation coefficient of chip's sawtooth and the chip thickness compression ratio is deduced as well. The comparison between these theoretical prediction curves and experimental data shows good agreement, which well validates the robustness of the ideal chip formation models and the correctness of the theoretical deducing analysis. The proposed ideal models may have provided a simple but effective theoretical basis for succeeding research on serrated chip morphology. Finally, the influences of most principal cutting factors on serrated chip formation are discussed on the basis of a series of finite element simulation results for practical advices of controlling serrated chips in engineering application.
Resumo:
The Dark Ages are generally held to be a time of technological and intellectual stagnation in western development. But that is not necessarily the case. Indeed, from a certain perspective, nothing could be further from the truth. In this paper we draw historical comparisons, focusing especially on the thirteenth and fourteenth centuries, between the technological and intellectual ruptures in Europe during the Dark Ages, and those of our current period. Our analysis is framed in part by Harold Innis’s2 notion of "knowledge monopolies". We give an overview of how these were affected by new media, new power struggles, and new intellectual debates that emerged in thirteenth and fourteenth century Europe. The historical salience of our focus may seem elusive. Our world has changed so much, and history seems to be an increasingly far-from-favoured method for understanding our own period and its future potentials. Yet our seemingly distant historical focus provides some surprising insights into the social dynamics that are at work today: the fracturing of established knowledge and power bases; the democratisation of certain "sacred" forms of communication and knowledge, and, conversely, the "sacrosanct" appropriation of certain vernacular forms; challenges and innovations in social and scientific method and thought; the emergence of social world-shattering media practices; struggles over control of vast networks of media and knowledge monopolies; and the enclosure of public discursive and social spaces for singular, manipulative purposes. The period between the eleventh and fourteenth centuries in Europe prefigured what we now call the Enlightenment, perhaps moreso than any other period before or after; it shaped what the Enlightenment was to become. We claim no knowledge of the future here. But in the "post-everything" society, where history is as much up for sale as it is for argument, we argue that our historical perspective provides a useful analogy for grasping the wider trends in the political economy of media, and for recognising clear and actual threats to the future of the public sphere in supposedly democratic societies.