Shaft transducer having dc output proportional to angular velocity

A brushless dc tachometer is disclosed that includes a high strength toroidal permanent magnet for providing a uniform magnetic field in an air gap, an annular pole piece opposite the magnet, and a pickup coil wound around the pole piece and adapted to rotate about the axis of the pole piece. The pickup coil is rotated by an input shaft to which the coil is coupled with the friction clip. The output of the coil is conducted to circuitry by a twisted wire pair. The input shaft also activates a position transducing potentiometer

Experimental results with a six-degree-of-freedom force-reflecting hand controller

Control experiments performed using an isotonic joystick connected to a six degree-of-freedom manipulator equipped with a six dimensional force-torque sensor at the base of the manipulator end effector are described. The preliminary control experiments were aimed at the investigation of the human operators' ability to command and control forces in different directions by varying the information conditions and the values of the feedforward and feedback command gains in the bilateral control loop. The main conclusions are: (1) a quantified graphic display of force-torque information can considerably enhance the operator's ability to perform a quantitatively sharp force-torque control, and (2) there seems to be a task dependent optimal combination of the feedforward and feedback command gain values which provide a dynamically smooth and stable bilateral control performance

Liberalismo à Brasileira: Um estudo sociológico sobre a genealogia do tipo de cidadão brasileiro (1822-1891)

Liberalismo à Brasileira: Um Estudo Sociológico Sobre a Genealogia do Tipo de Cidadão Brasileiro (1822-1891) é uma dissertação de mestrado em Sociologia a realizar um balanço crítico sobre a agenda do liberalismo brasileiro, a sua relação com a independência do Brasil e a escravidão, assim como a atuação do Estado brasileiro na promoção e difusão da cidadania formal durante o século XIX, e a omissão deste Estado em relação à cidadania substantiva. Problematiza-se nesta dissertação tanto a independência do Brasil, quanto o liberalismo brasileiro como uma revolução a construir um Estado democrático e de direito em paridade com as demais formações liberais internacionais, mas que permanece com práticas de gestão colonial em relação à sua gente. Desconstrói-se nesta dissertação a “ideologia do atraso” dos países em desenvolvimento, para encontrar a emergência dos cidadãos insurgentes enquanto práticas de liberdade e igualdade.The Brazilian way of Liberalism: A Sociological Study on the Genealogy of the Brazilian Citizen Type (1822-1891) is a master's thesis in Sociology that critically reviews the agenda of Brazilian liberalism, its relationship with Brazilian independence and slavery, as well as the Brazilian State’s promotion and diffusion of formal citizenship during the nineteenth century. Moreover, the State has omitted and neglected to provide substantive citizenship. This thesis discusses both the independence of Brazil and the Brazilian way of liberalism as a revolution building a democratic State and nation of law in parity with other international liberal formations, but which remains with colonial practices of governance of the population. This study provides a deconstruction of the “ideology of backwardness” in developing countries, thereby exploring the emergence of insurgent citizens related to practices of freedom and equality

Enhanced hydrogen production from thermochemical processes

To alleviate the pressing problem of greenhouse gas emissions, the development and deployment of sustainable energy technologies is necessary. One potentially viable approach for replacing fossil fuels is the development of a H2 economy. Not only can H2 be used to produce heat and electricity, it is also utilised in ammonia synthesis and hydrocracking. H2 is traditionally generated from thermochemical processes such as steam reforming of hydrocarbons and the water-gas-shift (WGS) reaction. However, these processes suffer from low H2 yields owing to their reversible nature. Removing H2 with membranes and/or extracting CO2 with solid sorbents in situ can overcome these issues by shifting the component equilibrium towards enhanced H2 production via Le Chatelier's principle. This can potentially result in reduced energy consumption, smaller reactor sizes and, therefore, lower capital costs. In light of this, a significant amount of work has been conducted over the past few decades to refine these processes through the development of novel materials and complex models. Here, we critically review the most recent developments in these studies, identify possible research gaps, and offer recommendations for future research

Exploring the politics of Free/Libre/Open Source Software (FLOSS) in the context of contemporary South Africa; how are open policies implemented in practice?

This research investigates the politics of FLOSS in the context of South Africa. The FLOSS policy was adopted in 2007. Multilateral agreements between governments around the world are now dealing with diverging laws regarding copyright, access to knowledge, transparency and secrecy. Based on fieldwork conducted in South Africa in 2010, this field note explores the gap between the policy and practice of openness. </jats:p

Exploring the politics of Free/Libre/Open Source Software (FLOSS) in the context of contemporary South Africa; how are open policies implemented in practice?

This research investigates the politics of FLOSS in the context of South Africa. The FLOSS policy was adopted in 2007. Multilateral agreements between governments around the world are now dealing with diverging laws regarding copyright, access to knowledge, transparency and secrecy. Based on fieldwork conducted in South Africa in 2010, this field note explores the gap between the policy and practice of openness