651 research outputs found
Revolution and Really Being Alive
A short account of how poetry can arouse premonitions of "revolutionary subjective universality", with comments on Rosa Luxemburg and Marx
Optimal periodic binary codes of lengths 28 to 64
Results from computer searches performed to find repeated binary phase coded waveforms with optimal periodic autocorrelation functions are discussed. The best results for lengths 28 to 64 are given. The code features of major concern are where (1) the peak sidelobe in the autocorrelation function is small and (2) the sum of the squares of the sidelobes in the autocorrelation function is small
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Sean Bonney's hate poems
An account of Sean Bonney;'s poetry that examines the relation of the work to the history of French anarchism after the massacre of the Paris Commune and to the culture of anarchist art among emigré poets and artists during the first world war. The essay proposes a category of poem, the 'hate poem', and offers some critical, historical and theoretical reflections on its potential significance
Prudential Regulations and Financial Performance of Commercial Banks in Kenya
Prudential regulation forms a critical part of operations in the banking sector. The aim of the regulations is to protect investors and consumers and ensure systemic stability. Consequently, commercial banks are required to maintain adequate level of capital, liquidity, asset quality, credit risk and management efficiency. In Kenya, the CBK implemented the prudential regulations in 2013. However, there is no consensus from existing studies whether the new regulations have a positive or negative influence on bank performance. The main objective of this study was to determine the effect of prudential regulations on the financial performance of commercial banks in Kenya. The sample comprised of all 43commercial banks operating in Kenya observed over the study period, 2013-2017.Data was extracted from annual financial reports of the banks and Central bank of Kenya (CBK) annual regulatory reports, which reduced the sample to 36 banks. The study adopted correlation research design and examined the relationship between the independent variables and performance. Multiple regression model was used to determine the linear relationship to examine the effect of the prudential regulations of profitability of commercial banks. From study findings, liquidity management, credit risk management and management efficiency has significant effect on the financial performance of commercial banks while capital adequacy and asset quality has no significant effect on the performance of commercial banks in Kenya. The research findings are useful to the CBK and banks, as it demonstrates the extent to which new prudential regulations influence the financial performance. Variables contributing positively to financial performance should be strengthened while those influencing performance negatively should be reviewed. This will enable the formulation of policies and strategies that will help in running the operations of commercial banks. The investment advisors and analysts use the research outcome to advise their clients on the future prospects and sustainability of investments in commercial banks. The study recommends adoption of the regulation as it affects banks financial performance thus improve banks stability and reduces chances of insolvency.Keywords: liquidity and credit risk management, management efficiency, capital adequacy and asset quality, financial performanceDOI: 10.7176/RJFA/11-14-06Publication date:July 31st 202
Analyzing state-dependent model–data comparison in multi-regime systems
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Computational Geosciences 15 (2011): 627-636, doi:10.1007/s10596-011-9229-3.An approach to analyze regime change in spatial time series data sets is
followed and extended to jointly analyze a dynamical model depicting regime shift
and observational data informing the same process. We analyze changes in the joint
model-data regime and covariability within each regime. The method is applied to two
observational data sets of equatorial sea surface temperature (TAO/TRITON array and
satellite) and compared with the predicted data by the ECCO-JPL modeling system.Funding for this work was provided by Spanish National Program on Space,
under contract ESP2005-06823-C05. A. Aretxabaleta has been additionally supported by a
Juan de la Cierva grant of the Spanish Government. K. Smith was supported by NSF Grant
DMS-0934653
Expectation-maximization analysis of spatial time series
© Author(s) 2007. This work is licensed
under a Creative Commons License. The definitive version was published in Nonlinear Processes in Geophysics 14 (2007): 73-77, doi: 10.5194/npg-14-73-2007Expectation maximization (EM) is used to estimate the parameters of a Gaussian Mixture Model for spatial time series data. The method is presented as an alternative
and complement to Empirical Orthogonal Function (EOF) analysis. The resulting weights, associating time
points with component distributions, are used to distinguish
physical regimes. The method is applied to equatorial Pacific
sea surface temperature data from the TAO/TRITON mooring
time series. Effectively, the EM algorithm partitions the
time series into El Nino, La Nina and normal conditions. The
EM method leads to a clearer interpretation of the variability
associated with each regime than the basic EOF analysis.This work was supported by NSF
grant DMS-0417845
Unusual case of intracranial dural AV fistula presenting with acute myelopathy
We present a case of intracranial arteriovenous fistula with perimedullary venous drainage presenting with acute myelopathy, which is an unusual presentation of this uncommon condition. Subsequent catheter angiogram defined the arterial feeders from the meningohypophyseal trunk and petrosal branch of the middle meningeal artery. The patient was successfully embolised, resulting in complete obliteration of the fistula, and significant resolution of brainstem and cervical cord changes along with clinical improvement
Bernstein Modes in a Weakly Relativistic e-e+ Plasma
This thesis examines the behaviour of a homogeneous and quasineutral, equal-mass (electron- positron) plasma in the presence of a constant magnetic field. Two sets of comparisons are made: between e-e+ and e--ion plasmas and between treatments of a progressively more relativistic nature. Fundamental plasma quantities: plasma frequency, op cyclotron frequency, O; and Debye length, lambdaD, are briefly introduced in Chapter 1. The peculiar features of electron-positron plasmas are illustrated in Chapter 2. Quantities defined in Chapter 1 are redefined for e-e+ plasmas. Examples of physical situations where e-e+ plasmas may occur are given. The predictions of cold plasma theory for e-e+ plasmas are summarized at the end of this chapter. Chapter 3 embraces the kinetic theory upon which the remainder of the thesis relies. After explaining the need for a kinetic theory, the development of that theory is reviewed. The first part of the chapter shows the microscopic (Klimontovich) description. Next the necessary concepts from Gibbs' and Boltzmann's statistical theory are presented. These ideas are married in the BBGKY hierarchy. The lowest order expansion of the hierarchy gives the Vlasov equation. A dielectric treatment can then be carried out using the Vlasov equation and Maxwell's equations. At this point the equilibrium conditions are stated. After some analysis general dispersion relations are found for both e- -ion and e-e+ plasmas. These expressions are general in the sense that they permit a choice of momentum distribution. In Chapter 4 the momentum distribution function is the familiar Maxwellian distribution function. The dispersion relations are then used to derive the (electrostatic) Bernstein modes. Bernstein modes propagate perpendicular to the magnetic field and resonate at electron cyclotron harmonics (o ≈ nOe). In an electron-ion plasma, there are seen to be gaps in the frequency spectrum away from nOe where these modes may not propagate. e-e+ plasmas are different: the theory leading to frequency gaps is exact and not a consequence of approximation. These relations are then illustrated. Original work begins in Chapter 5. In this thesis, interest in a weakly relativistic plasma stems from the wish to observe the transition between the existing non-relativistic and fully relativistic kinetic treatments. The relativistic nature of these treatments is governed by the parameter a=moc2/kT: 10 ≤ a ≤ 100 corresponds to weakly relativistic conditions. Chapter 5 is concerned with weakly relativistic e-e+ plasmas. A novel combination of non-relativistic distribution function and otherwise fully relativistic dispersion relation leads to the dispersion relation for weakly relativistic e-e+ plasmas. This expression is then prepared for inclusion in computer code: it is restated in dimensionless units and rearranged so that double quadrature becomes single quadrature with a special function. The design of the computer code is discussed in Chapter 6. The resulting dispersion curves are shown arid described in Chapter 7. It is demonstrated that, as for e--ion plasmas, the introduction of a weakly (or fully) relativistic treatment sees a broadening of the frequencies at which resonance occurs and a downshift in those frequencies. These results have been described briefly in conference proceedings [1,2]. This chapter goes on to consider the possibility of an approximate analytical approach and suggests the direction future work will take. There are three appendices. They deal respectively with: the properties of certain special functions; contour integration; and a listing of the code which is described in Chapter 6
For politics, people, or the planet? The political economy of fossil fuel reform, energy dependence and climate policy in Haiti
© 2019 Elsevier Ltd The uneven effects of the climate crisis and the need for decarbonization by reducing fossil fuel exploitation and eliminating subsidies create critical trade-offs and tensions for low-income developing countries. Recent reform of fuel consumption subsidies has shown a perennial mitigation bias largely imposed by external forces, in particular multilateral agencies and foreign governments in the context of the Paris accord. Contradictorily, external pressures to reduce subsidies have created competitive markets for multinationals to have a disproportionate role in supplying energy products which foreground the inequities in Haitian society that have spurred social and political resistance. Empirical work on energy-subsidy reform and climate policy do not sufficiently interrogate the interplay and implications of underlying assumptions, power imbalances between domestic and foreign actors, the challenging infrastructural and political context of renewable energy promotion, and immediate concerns to address worsening social conditions and development priorities. Drawing upon these policy debates, this paper considers the recent experience of Haiti to reform its energy subsidies required by the International Monetary Fund to enforce austerity. The paper takes a more integrated and critical approach to these policy discussions in a context of interconnecting political and socio-ecological crises and climate policy in Haiti. By inductively analyzing Haiti's main climate and energy policies and evidence drawn from field experience, the paper offers a more nuanced understanding of decarbonization and energy debates in this extremely vulnerable context. This approach gives priority to a more dynamic historical analysis of the socio-political context and factors that seek to advance climate justice
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