A broadband 180° hybrid ring coupler using a microstrip-to-slotline inverter

A new broadband 180° hybrid ring coupler with a Chebyshev return loss response, implemented in microstrip line, and a phase inverter using microstripto- slotline transitions, is presented. The transitions were constructed using via short circuits and optimized radial slot stubs. The manufactured prototype was found to operate over a 118% bandwidth in the frequency range 0.72-2.8 GHz.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1098-27602016-09-30hb201

A Critical Review Of The Basel Margin Of Conservatism Requirement In A Retail Credit Context

The Basel II accord (2006) includes guidelines to financial institutions for the estimation of regulatory capital (RC) for retail credit risk. Under the advanced Internal Ratings Based (IRB) approach, the formula suggested for calculating RC is based on the Asymptotic Risk Factor (ASRF) model, which assumes that a borrower will default if the value of its assets were to fall below the value of its debts. The primary inputs needed in this formula are estimates of probability of default (PD), loss given default (LGD) and exposure at default (EAD). Banks for whom usage of the advanced IRB approach have been approved usually obtain these estimates from complex models developed in-house. Basel II recognises that estimates of PDs, LGDs, and EADs are likely to involve unpredictable errors, and then states that, in order to avoid over-optimism, a bank must add to its estimates a margin of conservatism (MoC) that is related to the likely range of errors. Basel II also requires several other measures of conservatism that have to be incorporated. These conservatism requirements lead to confusion among banks and regulators as to what exactly is required as far as a margin of conservatism is concerned. In this paper, we discuss the ASRF model and its shortcomings, as well as Basel II conservatism requirements. We study the MoC concept and review possible approaches for its implementation. Our overall objective is to highlight certain issues regarding shortcomings inherent to a pervasively used model to bank practitioners and regulators and to potentially offer a less confusing interpretation of the MoC concept

Discovery: an interactive resource for the rational selection and comparison of putative drug target proteins in malaria

<p>Abstract</p> <p>Background</p> <p>Up to half a billion human clinical cases of malaria are reported each year, resulting in about 2.7 million deaths, most of which occur in sub-Saharan Africa. Due to the over-and misuse of anti-malarials, widespread resistance to all the known drugs is increasing at an alarming rate. Rational methods to select new drug target proteins and lead compounds are urgently needed. The Discovery system provides data mining functionality on extensive annotations of five malaria species together with the human and mosquito hosts, enabling the selection of new targets based on multiple protein and ligand properties.</p> <p>Methods</p> <p>A web-based system was developed where researchers are able to mine information on malaria proteins and predicted ligands, as well as perform comparisons to the human and mosquito host characteristics. Protein features used include: domains, motifs, EC numbers, GO terms, orthologs, protein-protein interactions, protein-ligand interactions and host-pathogen interactions among others. Searching by chemical structure is also available.</p> <p>Results</p> <p>An <it>in silico</it> system for the selection of putative drug targets and lead compounds is presented, together with an example study on the bifunctional DHFR-TS from <it>Plasmodium falciparum</it>.</p> <p>Conclusion</p> <p>The Discovery system allows for the identification of putative drug targets and lead compounds in Plasmodium species based on the filtering of protein and chemical properties.</p

A compact dual-circularly polarized cavity-backed ring-slot antenna

A low profile dual-circularly polarized printed ring-slot antenna with a small footprint, which radiates above an open cavity loaded with an artificial magnetic conducting reflector, is presented. The feed network consists of two T-shaped capacitive feed structures connected to a miniaturized hybrid branch-line coupler. Experimental results for a final antenna design (with a size of 0.5λ0 × 0.5λ0 × 0.057λ0) show a 4% isolation bandwidth between the two ports of the dual-circularly polarized antenna and a maximum gain of approximately 6.8 dBic. Good front-to-back ratios and low cross-polarization were achieved. These very compact and low profile antennas are suitable for 2.4 GHz wireless local area network (WLAN) communication systems.http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=8hb2017Electrical, Electronic and Computer Engineerin

The Macroeconomic, Industrial, Distributional and Regional Effects of Government Spending Programs in South Africa

A computable general equilibrium model of the South African economy (IDC-GEM) is outlined. The model is used to analyse the effects on the economy of increases in government spending such as are at the core of the new government's Reconstruction and Development Program. The analysis concentrates on the implications of alternative methods of finance for the program. Results are reported for macroeconomic variables, for the prospects of industries and regions, and for income distribution

The Macroeconomic, Industrial, Distributional and Regional Effects of Government Spending Programs in South Africa

A computable general equilibrium model of the South African economy (IDC-GEM) is outlined. The model is used to analyse the effects on the economy of increases in government spending such as are at the core of the new government's Reconstruction and Development Program. The analysis concentrates on the implications of alternative methods of finance for the program. Results are reported for macroeconomic variables, for the prospects of industries and regions, and for income distribution.economic modelling, South Africa, government spending, income distribution, industrial effects, regional effects, macroeconomic effects