1,681 research outputs found
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Goodbye to Projects? ¿ A livelihoods-grounded audit of the Magu District Livelihoods and Food Security Project (MDLFSP) in Tanzania
Approaches to projects and development have undergone considerable change in the last
decade with significant policy shifts on governance, gender, poverty eradication, and
environmental issues. Most recently this has led to the adoption and promotion of the
sustainable livelihood (SL) approach. The adoption of the SL approach presents
challenges to development interventions including: the future of projects and
programmes, and sector wide approaches (SWAPs) and direct budgetary support. This paper `A livelihoods-grounded audit of the Magu District Livelihoods and Food
Security Project¿ is the ninth in the series of project working papers.Department for International Developmen
Limits on the dark matter particle mass from black hole growth in galaxies
I review the properties of degenerate fermion balls and investigate the dark
matter distribution at galactic centers using NFW, Moore and isothermal density
profiles. I show that dark matter becomes degenerate for particles masses of a
few keV at distances less than a few parsec from the center of our galaxy. To
explain the galactic center black hole of mass of and a supermassive black hole of at a redshift of 6.41 in SDSS quasars, the mass of the fermion
ball is assumed to be between and . This constrains the mass of the dark matter particle between
and . The lower limit on the dark matter mass is
improved to about {\rm 6 keV} if exact solutions of Poisson's equation are used
in the isothermal power law case. The constrained dark matter particle could be
interpreted as a sterile neutrino.Comment: 3 pages, To be published in Proceedings of the 11th Marcel Grossmann
meeting on general relativity, 23-29 July 2006, Berlin, German
Recommended from our members
Goodbye to Projects? ¿ A livelihoods-grounded audit of the Agricultural Sector Programme Support (ASPS) in Tanzania
Approaches to projects and development have undergone considerable change in the last decade with significant policy shifts on governance, gender, poverty eradication, and environmental issues. Most recently this has led to the adoption and promotion of the sustainable livelihood (SL) approach. The adoption of the SL approach presents challenges to development interventions including: the future of projects and programmes, and sector wide approaches (SWAPs) and direct budgetary support.This paper `A livelihoods-grounded audit of Agricultural Sector Programme Support (ASPS) ¿ Tanzania¿ is the seventh in the series of project working papers.Department for International Developmen
How far can you see in a forest?
We address a visibility problem posed by Solomon & Weiss. More precisely, in
any dimension , we construct a forest \F with finite
density satisfying the following condition : if \e > 0 denotes the radius
common to all the trees in \F, then the visibility \V therein satisfies the
estimate \V(\e) = O(\e^{-2d-\eta}) for any , no matter where we
stand and what direction we look in. The proof involves Fourier analysis and
sharp estimates of exponential sums.Comment: This is an extended version of a paper to appear. Minor typos have
been correcte
Vertical shift and simultaneous Diophantine approximation on polynomial curves
The Hausdorff dimension of the set of simultaneously tau well approximable
points lying on a curve defined by a polynomial P(X)+alpha, where P(X) is a
polynomial with integer coefficients and alpha is in R, is studied when tau is
larger than the degree of P(X). This provides the first results related to the
computation of the Hausdorff dimension of the set of well approximable points
lying on a curve which is not defined by a polynomial with integer
coefficients. The proofs of the results also include the study of problems in
Diophantine approximation in the case where the numerators and the denominators
of the rational approximations are related by some congruential constraint.Comment: 22
A note on the Hausdorff dimension of some liminf sets appearing in simultaneous Diophantine approximation
Let Q be an infinite set of positive integers. Denote by W_{\tau, n}(Q)
(resp. W_{\tau, n}) the set of points in dimension n simultaneously
\tau--approximable by infinitely many rationals with denominators in Q (resp.
in N*). A non--trivial lower bound for the Hausdorff dimension of the liminf
set W_{\tau, n}\W_{\tau, n}(Q) is established when n>1 and \tau >1+1/(n-1) in
the case where the set Q satisfies some divisibility properties. The
computation of the actual value of this Hausdorff dimension as well as the
one--dimensional analogue of the problem are also discussed
On the Minimum of a Positive Definite Quadratic Form over Non--Zero Lattice points. Theory and Applications
Let be the set of positive definite matrices with determinant
1 in dimension . Identifying any two -congruent
elements in gives rise to the space of reduced quadratic forms
of determinant one, which in turn can be identified with the locally symmetric
space .
Equip the latter space with its natural probability measure coming from a Haar
measure on . In 1998, Kleinbock and Margulis established
sharp estimates for the probability that an element of takes a value less
than a given real number over the non--zero lattice points
.
In this article, these estimates are extended to a large class of probability
measures arising either from the spectral or the Cholesky decomposition of an
element of . The sharpness of the bounds thus obtained are also
established (up to multiplicative constants) for a subclass of these measures.
Although of an independent interest, this theory is partly developed here
with a view towards application to Information Theory. More precisely, after
providing a concise introduction to this topic fitted to our needs, we lay the
theoretical foundations of the study of some manifolds frequently appearing in
the theory of Signal Processing. This is then applied to the recently
introduced Integer-Forcing Receiver Architecture channel whose importance stems
from its expected high performance. Here, we give sharp estimates for the
probabilistic distribution of the so-called \emph{Effective Signal--to--Noise
Ratio}, which is an essential quantity in the evaluation of the performance of
this model
Recommended from our members
Goodbye to Projects? - Review of development interventions in Tanzania: From projects to livelihoods approaches
Approaches to projects and development have undergone considerable change in the last decade with significant policy shifts on governance, gender, poverty eradication, and environmental issues. Most recently this has led to the adoption and promotion of the sustainable livelihood (SL) approach. The adoption of the SL approach presents challenges to development interventions including: the future of projects and programmes, and sector wide approaches (SWAPs) and direct budgetary support. This paper `A Review of Approaches to Development Interventions in Tanzania: From Projects to Livelihood Approaches¿ is the third in the series of the project working papers. This is the output of a literature review and semi-structured interviewing in Tanzania.Department for International Developmen
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