On the dynamics of the Furuta pendulum

The Furuta pendulum, or rotational inverted pendulum, is a system found in many control labs. It provides a compact yet impressive platform for control demonstrations and draws the attention of the control community as a platform for the development of nonlinear control laws. Despite the popularity of the platform, there are very few papers which employ the correct dynamics and only one that derives the full system dynamics. In this paper, the full dynamics of the Furuta pendulum are derived using two methods: a Lagrangian formulation and an iterative Newton-Euler formulation. Approximations are made to the full dynamics which converge to the more commonly presented expressions. The system dynamics are then linearised using a Jacobian. To illustrate the influence the commonly neglected inertia terms have on the system dynamics, a brief example is offered.Benjamin Seth Cazzolato and Zebb Prim

Rainwater harvesting, alternative to the water supply in Indian urban areas : The case of Ahmedabad in Gujarat

Water scarcity is a characteristic of north-western states of India, such as Gujarat. Over time, the continuous increase of the population as well as the financial, administrative and technical deficiencies of the new supply system have lead to the deterioration of the water service in the city. In the meantime, the water demand has considerably increased due to the improvement of standards of living. This has resulted in an increasing pressure on underground water resources, which has lead to an alarming depletion of aquifers. From this overall situation arises the question of the use of complementary alternative sources of water in Ahmedabad and more particularly of the rehabilitation of the rainwater harvesting structures still existing in its old city area. The objective of the research is to evaluate to what extent this traditional system may constitute an additional source of water within the Old city of Ahmedabad and may locally reduce the pressure on water demand, assuming that the existing supply system does not fulfil the needs of the users. The results of an exploratory field study conducted in the Old city in 2001-02, which combined quantitative and qualitative aspects, give an outlook on people's opinions and behaviors regarding both systems. Finally, the rehabilitation of rainwater harvesting structures in the Old city of Ahmedabad suggests the necessity of empowering local structures of water management (households, non governmental association) in semi-arid urban areas to create the conditions for a sustainable implementation.rainwater harvesting ; water supply ; water scarcity ; water management ; Ahmedabad Old City ; Pol ; Gujarat ; India

Rainwater Harvesting, Alternative to the Water supply in Indian Urban Areas : the Case of Ahmedabad in Gujarat.

NAgestion de l'eau;développement;récupération de l'eau de pluie;Inde

India and WWI: balancing demands of war with defence of Empire

During WWI, India found itself in the unusual position of being low on the British Empire’s list of concerns. Adam Prime explores the competing priorities of the British in the Great War, highlighting that while Kitchener was keen to divert troops from India to Europe, the colonial leadership feared that losing the British military presence would lead to the collapse of the Raj

Synthesis of α-hydroxy-β,β-difluoro-γ-ketoesters via [3,3]sigmatropic rearrangements

Readily available γ,γ-difluorinated allylic alcohols obtained from trifluoroethanol were esterified efficiently. Exposure to strong base (LDA) afforded the ester enolates, in which chelation both controlled configuration and stabilised against fragmentation, which were trapped as their silyl ketene acetals. Rearrangement occurred to afford base-sensitive acid products. Esterification under mild conditions afforded the purifiable methyl esters in which the masked ketone had been released. Educts with either a benzyloxy or an allyloxy group at the α-position could be deprotected releasing the alcohols

The equilibrium melting of polymers

Equilibrium melting of polymer

Quality of Service for Information Access

Information is available in many forms from different sources, in distributed locations; access to information is supported by networks of varying performance; the cost of accessing and transporting the information varies for both the source and the transport route. Users who vary in their preferences, background knowledge required to interpret the information and motivation for accessing it, gather information to perform many different tasks. This position paper outlines some of these variations in information provision and access, and explores the impact these variations have on the user’s task performance, and the possibilities they make available to adapt the user interface for the presentation of information

Setting Australia’s post-2020 target for greenhouse gas emissions: issues paper

The Australian Government will announce Australia’s post-2020 emissions reduction target in mid-2015. This paper presents the factors that will be considered when deciding the target, and invites submissions from the public. Abstract Climate change is a global problem that requires a global solution. The Australian Government has committed to review Australia’s greenhouse gas emissions reduction targets and settings this year. This review is in the context of negotiations for a new global climate agreement to be concluded at the United Nations Framework Convention on Climate Change (UNFCCC) Conference of the Parties in Paris in late 2015 (30 November to 11 December). All countries have agreed to propose a post-2020 emissions reduction target well in advance of the Paris conference. Australia will announce a post-2020 emissions reduction target in mid‑2015.   You can make a submission here. Submissions close 3pm AEST on Friday 24 April 2015