INVESTIGATION OF THE VISUAL BOUNDARY FOR IMMEDIATE PERCEPTION OF VERTICAL RATE OF DESCENT

Visual boundary for human perception of vertical rate of descen

Cultural Change for a Bearable Climate

Social, economic and cultural systems will have to evolve so that they can again exist within the boundaries of nature Stabilising the climate and curbing ecological decline more broadly will take nothing less than transforming cultural systems so that living sustainably becomes as natural as living as a consumer feels today. To do that, it will be necessary to harness leading societal institutions just as consumer interests did in the past century, when they so effectively normalised consumerism

Low-Speed Wind-Tunnel Tests of a Pilotless Aircraft Having Horizontal and Vertical Wings and Cruciform Tail

Low-speed tests of a pilotless aircraft were conducted in the Langley propeller-research tunnel to provide information for the estimation of the longitudinal stability and. control, to measure the aileron effectiveness, and to calibrate the radome and the Machmeter pitot-static orifices. It was found that the model possessed a stEb.le variation of elevator angle required for trim throughout the speed range at the design angle of attack. A comparison of the airplane with and without JATO units and with an alternate rocket booster showed that a large loss in longitudinal stability and control resulting from the addition of the rocket booster to the aircraft was sufficient to make the rocket-booster assembly unsatisfactory as an alternate for the JATO units. Reversal of the aileron effectiveness was evident at positive deflections of the vertical wing flap indicating that the roll-stabilization system would produce roiling moments in a tight right turn contrary to its design purpose. Vertical-wing-flap deflections caused large errors in the static-pressure reading obtained by the original static-tube installation. A practical installation point on the fuselage was located which should yield reliable measurement of the free-stream static pressure

Colonial Organization of Mine Labour in Charcas 1 (Present-Day Bolivia) and Its Consequences 2 (Sixteenth to the Seventeenth Centuries)

This article analyses the changes in the organization of labour during the sixteenth and seventeenth centuries in colonial Charcas, present-day Bolivia, focusing on the role that different colonial authorities played in this process and its consequences. The Spanish took advantage of the pre-Hispanic organization of labour from the beginning of their conquest. However, in a colonial context, labour relations changed significantly, and the architect of those alterations was Viceroy Francisco de Toledo. We examine the transformations in mine labour carried out by the Spanish colonial polity; these had a significant effect not only on mining, but also on all labour relations in the southern colonial Andes.Fil: Gil Montero, Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto de Geografía, Historia y Ciencias Sociales. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Geografía, Historia y Ciencias Sociales; ArgentinaFil: Zagalsky, Paula Cecilia. Universidad Nacional de Jujuy; Argentina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Five centuries of Latin American income inequality

Special Issue on Latin American InequalityMost analysts of the modern Latin American economy believe that it has always had very high levels of inequality. Indeed, some have argued that high inequality appeared very early in the post-conquest Americas, and that this fact supported rent-seeking and anti-growth institutions that help explain the disappointing growth performance we observe there even today. This paper argues to the contrary. Compared with the rest of the world, Latin American inequality was not high either in pre-conquest 1491 or in the post-conquest decades following 1492. Indeed, it was not even high in the mid-19th century just before Latin America’s belle e´poque. It only became high thereafter. Historical persistence in Latin American inequality is a myth.La mayoría de los análisis sobre la economía latinoamericana contemporánea creen que siempre ha tenido muy altos niveles de desigualdad. A decir verdad, algunos han argumentado que los altos niveles de desigualdad aparecieron en épocas muy tempranas en la América posterior a la Conquista. Esto supondría la existencia de instituciones buscadoras de renta y no propiciatorias del crecimiento lo que nos ayudaría a explicar los problemas de desarrollo que observamos incluso hoy en día. Este artículo argumenta lo contrario. Comparada con el resto del mundo, la desigualdad en Latinoamérica no era alta en los años anteriores a la Conquista de 1491, y no fue alta en las décadas posteriores que siguieron a 1492. En realidad, no fue alta a mitad del siglo XIX en los años anteriores a la belle époque en Latinoamérica. Sólo llegó a ser alta posteriormente. La persistencia histórica de la desigualdad en Latinoamérica es un mito