3,565 research outputs found
Finite homological dimension and a derived equivalence
For a Cohen-Macaulay ring , we exhibit the equivalence of the bounded
derived categories of certain resolving subcategories, which, amongst other
results, yields an equivalence of the bounded derived category of finite length
and finite projective dimension modules with the bounded derived category of
projective modules with finite length homologies. This yields isomorphisms of
various generalized cohomology groups (like K-theory) and improves on terms of
a spectral sequence and Gersten complexes.Comment: 23 pages : Some parts of the article changed, especially section 3,
to add clarity. Other minor corrections mad
Indexing pensions
Pension indexation should anchor the parameters of the pension system to one or more economic and demographic variables to ensure that the system is implemented in a sustainable way, while minimizing distortions affecting important economic choices. Arguing that financial sustainability, incentive compatibility and consistency across multiple government programs are critical, the author examine the many linkages between the various parameters of pension schemes. Finally, the author turn to the cost of the insurance dimension of indexation, and suggest that option pricing techniques could be used to price indexation guarantees, and that this approach may suggest refinements to indexation practice not thus far implemented.Emerging Markets,Debt Markets,Pensions&Retirement Systems,Economic Theory&Research,Markets and Market Access
A Regulatory approach to financial product advice and distribution
Financial distribution, where the distributor is the agent of both the product provider and the customer has been found to inherently work against the interests of customers, in the form of high service fees and perverse incentives in sales practices. This paper proposes segregation of financial advice from financial distribution. It proposes a Financial Advisers Bill, 2012, to promote the development of a market for advice. The Bill suggests that financial advisers be recognised as professionals and be regulated under a new statutory body called the Institute of Financial Advisers of India. The paper suggests that regulation of distributors continue to remain under the purview of product regulators. It outlines alternative models in which the distribution market may be organised. It also points out that the Ministry of Finance and the Financial Stability and Development Council need to play an active role in co-ordinating the setting of common standards for distribution across all product regulators.Consumer Protection; distribution regulation; mutual funds; insurance; pensions; investment advice
Civil service and military pensions in India
This paper describes the New Pension System (NPS), an individual account defined contribution pension scheme introduced for civil servants in India, and the problems faced in implementation of this system. We describe what has been achieved in the implementation of the NPS, and the challenges ahead. We also document the state of military pensions which have not been a part of the reform process.
The aerodynamic effects of wing rotation and a revised quasi-steady model of flapping flight
We used a dynamically scaled model insect to measure the rotational forces produced by a flapping insect wing. A steadily translating wing was rotated at a range of constant angular velocities, and the resulting aerodynamic forces were measured using a sensor attached to the base of the wing. These instantaneous forces were compared with quasi-steady estimates based on translational force coefficients. Because translational and rotational velocities were constant, the wing inertia was negligible, and any difference between measured forces and estimates based on translational force coefficients could be attributed to the aerodynamic effects of wing rotation. By factoring out the geometry and kinematics of the wings from the rotational forces, we determined rotational force coefficients for a range of angular velocities and different axes of rotation. The measured coefficients were compared with a mathematical model developed for two-dimensional motions in inviscid fluids, which we adapted to the three-dimensional case using blade element theory. As predicted by theory, the rotational coefficient varied linearly with the position of the rotational axis for all angular velocities measured. The coefficient also, however, varied with angular velocity, in contrast to theoretical predictions. Using the measured rotational coefficients, we modified a standard quasi-steady model of insect flight to include rotational forces, translational forces and the added mass inertia. The revised model predicts the time course of force generation for several different patterns of flapping kinematics more accurately than a model based solely on translational force coefficients. By subtracting the improved quasi-steady estimates from the measured forces, we isolated the aerodynamic forces due to wake capture
Surface tension of flowing soap films
The surface tension of flowing soap films is measured with respect to the
film thickness and the concentration of soap solution. We perform this
measurement by measuring the curvature of the nylon wires that bound the soap
film channel and use the measured curvature to parametrize the relation between
the surface tension and the tension of the wire. We find the surface tension of
our soap films increases when the film is relatively thin or made of soap
solution of low concentration, otherwise it approaches an asymptotic value 30
mN/m. A simple adsorption model with only two parameters describes our
observations reasonably well. With our measurements, we are also able to
measure Gibbs elasticity for our soap film.Comment: 14 pages, 4 figure
Curves on surfaces and surgeries
We study collections of curves in generic position on a closed surface whose complement consists of one disk only, up to orientation-preserving homeomorphism of the surface. We define a surgery operation on the set of such collections and prove that any two of them can be connected by a sequence of such surgeries
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