2,461 research outputs found

    The Logic of Social Enterprise : The Big Issue Organization and New Labour Policy at the Millennial Juncture

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    This paper explores the emergence of and policies and practices underpinning ‘social enterprise’ in Britain: that is, the concept that businesses could provide social services and benefits while returning profits to those who have invested in them. This paper argues that, in Britain, the concept was massaged into existence and adopted as a business and policy model at a particular historical juncture, in the later 1990s and early 2000s. The process involved a careful interweaving of linguistic maneuvers with financial calculations both at the level of specific businesses and at that of political regimes. This process is traced here with reference to a specific organization, the Big Issue, and a particular policy regime, introduced by the New Labour government between 1997 and 2005. For the former, the transition from business activity focused on the Big Issue magazine to brokering activities for the “social enterprise” sector generally is tracked. The New Labour government’s concurrent focus on “social exclusion” and rearticulation of terms denoting sectors providing public services are traced. Thus, light is thrown on the relationship between the strategic terminology deployed at the ground-level of business operations and the top-down level of governmental policy and welfare restructuring in this period

    A Conformal Mapping Based Fractional Order Approach for Sub-optimal Tuning of PID Controllers with Guaranteed Dominant Pole Placement

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    A novel conformal mapping based Fractional Order (FO) methodology is developed in this paper for tuning existing classical (Integer Order) Proportional Integral Derivative (PID) controllers especially for sluggish and oscillatory second order systems. The conventional pole placement tuning via Linear Quadratic Regulator (LQR) method is extended for open loop oscillatory systems as well. The locations of the open loop zeros of a fractional order PID (FOPID or PI{\lambda}D{\mu}) controller have been approximated in this paper vis-\`a-vis a LQR tuned conventional integer order PID controller, to achieve equivalent integer order PID control system. This approach eases the implementation of analog/digital realization of a FOPID controller with its integer order counterpart along with the advantages of fractional order controller preserved. It is shown here in the paper that decrease in the integro-differential operators of the FOPID/PI{\lambda}D{\mu} controller pushes the open loop zeros of the equivalent PID controller towards greater damping regions which gives a trajectory of the controller zeros and dominant closed loop poles. This trajectory is termed as "M-curve". This phenomena is used to design a two-stage tuning algorithm which reduces the existing PID controller's effort in a significant manner compared to that with a single stage LQR based pole placement method at a desired closed loop damping and frequency.Comment: 23 pages, 7 figures, in press; Communications in Nonlinear Science and Numerical Simulations, 201

    A Null-model Exhibiting Synchronized Dynamics in Uncoupled Oscillators

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    The phenomenon of phase synchronization of oscillatory systems arising out of feedback coupling is ubiquitous across physics and biology. In noisy, complex systems, one generally observes transient epochs of synchronization followed by non-synchronous dynamics. How does one guarantee that the observed transient epochs of synchronization are arising from an underlying feedback mechanism and not from some peculiar statistical properties of the system? This question is particularly important for complex biological systems where the search for a non-existent feedback mechanism may turn out be an enormous waste of resources. In this article, we propose a null model for synchronization motivated by expectations on the dynamical behaviour of biological systems to provide a quantitative measure of the confidence with which one can infer the existence of a feedback mechanism based on observation of transient synchronized behaviour. We demonstrate the application of our null model to the phenomenon of gait synchronization in free-swimming nematodes, C. elegans

    Comparative study to assess the outcome of omitting bladder flap formation from caesarean delivery

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    Background: The aim of this study is to evaluate the effects of omitting the step of bladder flap formation at lower-segment caesarean delivery.Methods: It is a RCT (randomised control trial), non-blinded study conducted in a tertiary care hospital. A total of 104 women who underwent caesarean delivery (elective or emergency) were prospectively randomized to one of the two groups. In the study group (n= 54), caesarean was performed without formation of a bladder flap. In the control group (n=50), caesarean was performed with the formation of a bladder flap before the uterine incision.Results: There were differences of median skin incision to delivery interval (5 versus 6.5 minutes, P <0.0001), median total operating time (35 versus 44.5 minutes, P 0.0002), and median blood loss (haemoglobin 0.5 versus 1g/dl, P 0.0001) in favor of the study group. Postoperative incidence of urinary tract infection was reduced in the study group (1% versus 9%, P <0.0006) and bowel function returned early in the study group (day 2 versus 3, P<0.0001).  Bladder flap formation step was successfully omitted in (11/18, 61.11%) of previous CS (caesarean section) patients in the study group and (7/12, 58.33%) in control group illustrating that unless required, BF (bladder flap) formation step can even be omitted in previous CS patients.Conclusions: Omission of the bladder flap provides short term advantages such as reduction of total operating time, incision-delivery interval, and reduced blood loss and that this technique can even be applied in previous caesarean section patients
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