African Regional Integration: Implications for Food Security

This report looks at the African regional trade, regional integration agreements (RIAs) and the implications for food security. An overview is presented on the present state of African regional integration and the determinants of regional trade in agriculture and food commodities. In particular the study focuses on eight target countries, related RIAs and a set of strategic food commodities. The evidence presented in this study shows that African countries have made progress in opening up agriculture and food trade with partner countries. With, the exception of Ghana, Tanzania and Mozambique, the effective applied tariff rates for regional trade partners are substantially lower than the (MFN) rates applied to world trade partners. Nonetheless, regional trade in agriculture and food only increased marginally between 1990 and 2009, and is relatively low in comparison with other developing regions. The weak state of soft and hard infrastructure, rather than high trade tariffs, seem to be the cause of thi

Simple bounds for queueing systems with breakdowns

Computationally attractive and intuitively obvious simple bounds are proposed for finite service systems which are subject to random breakdowns. The services are assumed to be exponential. The up and down periods are allowed to be generally distributed. The bounds are based on product-form modifications and depend only on means. A formal proof is presented. This proof is of interest in itself. Numerical support indicates a potential usefulness for quick engineering and performance evaluation purposes

Simple and insensitive bounds for a grading and an overflow model

Simple and intuitively obvious lower and upper bounds are suggested for a specific grading and an overflow model. The bounds are based on product-type modifications and are insensitive. Numerical support indicates a potential usefulness for quick engineering purposes

Industry Evolution in Developing Countries: the Indonesian Pulp and Paper Industry

Industry, evolution, developing countries, Indonesia, industry

KLEVER: An experiment to measure \boldmath{BR(KL→π0νν‾){\rm BR}(K_L \to \pi^0 \nu \overline{\nu})} at the CERN SPS

The KLEVER experiment aims to measure ${\rm BR}(K_L \to \pi^0 \nu \overline{\nu})$, supplementing the ongoing NA62 measurement of ${\rm BR}(K^+ \to \pi^+ \nu \overline{\nu})$, to provide new input on CKM unitarity and potentially new physics. KLEVER is undergoing continuous development, with particular efforts focused on the design of the target and the beamline. As described here, adaptations are required relative to the K12 beamline in its current format, and a series of simulations has been performed to ensure that an adequate particle flux can be achieved while simultaneously suppressing problematic backgrounds.Comment: Published under licence CC-BY in Journal of Physics: Conference Series (JPCS) by IOP Publishing Ltd, proceedings of 6th Symposium on Prospects in the Physics of Discrete Symmetries, DISCRETE 2018, 26-30 Nov. 2018, Vienna, Austri

Industrial Policy and Technology Diffusion: Evidence from Paper Making Machinery in Indonesia

technology diffusion, Indonesia

Short-term volatility versus long-term growth: evidence in US macroeconomic time series

We test for a change in the volatility of 215 US macroeconomic time series over the period 1960-1996. We find that about 90\\% of these series have experienced a break in volatility during this period. This result is robust to controlling for instability in the mean and business cycle nonlinearities. Real variables have seen a reduction in volatility since the early 1980s, which is accompanied by lower but steadier output growth. Furthermore, nominal variables have seentemporary increases in their volatility around the early 1980s. This suggests the existence of a trade-off between short-term volatility and the long-term pattern of growth.growth;Volatility;Business cycle nonlinearity;Structural change tests

Monotonicity and error bounds for networks of Erlang loss queues

Networks of Erlang loss queues naturally arise when modelling finite communication systems without delays, among which, most notably are (i) classical circuit switch telephone networks (loss networks) and (ii) present-day wireless mobile networks. Performance measures of interest such as loss probabilities or throughputs can be obtained from the steady state distribution. However, while this steady state distribution has a closed product form expression in the first case (loss networks), it does not have one in the second case due to blocked (and lost) handovers. Product form approximations are therefore suggested. These approximations are obtained by a combined modification of both the state space (by a hypercubic expansion) and the transition rates (by extra redial rates). It will be shown that these product form approximations lead to (1) upper bounds for loss probabilities and \ud (2) analytic error bounds for the accuracy of the approximation for various performance measures.\ud The proofs of these results rely upon both monotonicity results and an analytic error bound method as based on Markov reward theory. This combination and its technicalities are of interest by themselves. The technical conditions are worked out and verified for two specific applications:\ud (1)• pure loss networks as under (2)• GSM networks with fixed channel allocation as under.\ud The results are of practical interest for computational simplifications and, particularly, to guarantee that blocking probabilities do not exceed a given threshold such as for network dimensioning