11,980 research outputs found
When it is necessary or not necessary to start horizontal purchasing collaboration in developing countries: the case for Uganda public procurement units
Bank-Lending Channel in South Africa: Bank-Level Dynamic Panel Date Analysis
The paper investigates the bank-lending channel (BLC) of monetary policy in South Africa using quarterly bank-level data for the period 2000Q1-2004Q4. Capital adequacy and bank size are used as indicators for information problems faced by banks when they look for external finance. Utilising dynamic panel estimation methods the study shows that BLC operates in South Africa. The finding has some policy implications. First, there is need to coordinate monetary policy with financial innovations and prudential banking regulations. Second, the overall effects of monetary policy pursued by the South African Reserve Bank cannot be completely characterised by interest rates only.Monetary policy transmission, Bank-lending channel, Dynamic panel, GMM estimator
Modeling of Generic Air Pollution Dispersion Analysis from Cement Factory
Air pollution from cement factory is classified as one of the sources of air pollution. The control of the air pollution by addressing the wind field dynamics was the main
objective of the paper. The dynamics of dispersion showed a three way flow which was calculated and explained accordingly. The 3D model showed good level of accuracy by
determining field values of air deposited pollutants. Mean concentration of diffusing pollutants was shown to be directly proportional to the plume angular displacement. The 2D model explained the details of the wind field dynamics and proffers a solution which may be
relevant in controlling air pollution from anthropogenic source
Policies on free primary and secondary education in East Africa: a review of the literature
Kenya, Tanzania and Uganda are among the countries in Sub-Saharan Africa which have recently implemented policies for free primary education, motivated in part by renewed democratic accountability following the re-emergence of multi-party politics in the 1990s. However, it is not the first time that the goal of expanding primary education has been pursued by these three neighbouring countries which have much in common. Since the 1960s, they have attempted to expand access at various levels of their education systems albeit with differences in philosophy and in both the modes and successes of implementation. All three countries continue to face the challenges of enrolling every child in school, keeping them in school and ensuring that meaningful learning occurs for all enrolled children. This paper provides an a review of the three countriesâ policies for expanding access to education, particularly with regard to equity and the enrolment of excluded groups since their political independence in the 1960s. It considers policies in the light of the countriesâ own stated goals alongside the broader international agendas set by the Millennium Development Goals and in particular, âEducation for Allâ. It is concerned with the following questions: What led to those policies and how were they funded? What was the role, if any, of the international community in the formulation of those policies? What were the politics and philosophies surrounding the formulation of those policies, have the policies changed over time, and if so how and why? The paper also discusses the range of strategies for implementation adopted. Tremendous growth has occurred in access to primary education since the 1960s, not least in Kenya, Tanzania and Uganda. The challenge of providing equitable access to schooling has been addressed in a series of education drives with varying motivations, modalities and degrees of success, the most recent of which pays attention to the increasingly pressing question of the transition to secondary education. The success of such policy remains to be seen but will be crucial for the widening of access to the benefits of education and to economic opportunity, particularly for those groups which history has so far excluded
Scaling laws for soliton pulse compression by cascaded quadratic nonlinearities
We present a detailed study of soliton compression of ultra-short pulses
based on phase-mismatched second-harmonic generation (\textit{i.e.}, the
cascaded quadratic nonlinearity) in bulk quadratic nonlinear media. The
single-cycle propagation equations in the temporal domain including
higher-order nonlinear terms are presented. The balance between the quadratic
(SHG) and the cubic (Kerr) nonlinearity plays a crucial role: we define an
effective soliton number -- related to the difference between the SHG and the
Kerr soliton numbers -- and show that it has to be larger than unity for
successful pulse compression to take place. This requires that the phase
mismatch be below a critical level, which is high in a material where the
quadratic nonlinearity dominates over the cubic Kerr nonlinearity. Through
extensive numerical simulations we find dimensionless scaling laws, expressed
through the effective soliton number, which control the behaviour of the
compressed pulses. These laws hold in the stationary regime, in which
group-velocity mismatch effects are small, and they are similar to the ones
observed for fiber soliton compressors. The numerical simulations indicate that
clean compressed pulses below two optical cycles can be achieved in a
-barium borate crystal at appropriate wavelengths, even for picosecond
input pulses.Comment: 11 pages, 8 figures, resubmitted version, to appear in October issue
of J. Opt. Soc. Am. B. Substantially revised, updated mode
Dewpoint temperature inversions analyzed
Dewpoint temperature inversion, with regard to other simultaneous meteorological conditions, was examined to establish the influence of meteorological variables on the variation of dewpoint temperature with height. This report covers instrumentation and available data, all the climatological features of dewpoint inversions, and specific special cases
Prospectives in Deep Space Infrastructures, Development, and Colonization
The realization of the long studied cost reduction benefits of reusable rockets is expected to revolutionize and enable both commercial deep space beyond Geostationary Earth Orbit (GEO) and solar system human colonization. The projections for a myriad of space commercialization activities beyond the current largely positional Earth utilities and Humans Mars both safe and affordable may now be realizable. This report considers these putative commercial and colonizationrelated activities, the emerging technologies, the space functionalities to support and further enable them, and envisions the nature of space developments beyond GEO going forward
Nonlocal explanation of stationary and nonstationary regimes in cascaded soliton pulse compression
We study soliton pulse compression in materials with cascaded quadratic
nonlinearities, and show that the group-velocity mismatch creates two different
temporally nonlocal regimes. They correspond to what is known as the stationary
and nonstationary regimes. The theory accurately predicts the transition to the
stationary regime, where highly efficient pulse compression is possible.Comment: 3 pages, 2 figures, published verison in Optics Letters. Contains
revised equations, including an updated mode
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