1,437 research outputs found
The Short-Run Impact of fluctuating primary commodity prices on three developing economies: Colombia, Ivory Coast and Kenya
Computable general equilibrium models are used to study the short-run impact of fluctuating primary commodity prices on the economies of Colombia, Ivory Coast and Kenya. The results indicate that these economies are destabilized by primary commodity price fluctuations unless governments act to hold real domestic absorption constant. To achieve this, however, would require foreign exchange reserves in excess of the level normally available to these governments for the purpose of stabilising, domestic economic activity.
Stabilisation strategies in primary commodity exporting countries: A case study of Chile
A number of recent studies have shown that the short term level of economic activity and employment in primary commodity exporting countries is particularly vulnerable to price fluctuations in world commodity markets. The authorities in such countries, in seeking to maintain output and employment stability, must invoke compensatory macroeconomic adjustment strategies to accommodate both favourable and unfavourable movements in the foreign terms of trade. Chile provides a case in point. Chile has traditionally been heavily reliant on raw materials exports, particularly copper, for its foreign exchange earnings. Copper exports averaged around 70 per cent of total export earnings for the period 1960-19 76. They currently represent about one half of total foreign exchange earnings.
Enabling Automatic Password Change in Password Managers Through Crowdsourcing
Password managers can immensely increase password security, for laymen and experts alike. One reason for the low adaption is a lack of automatic password change. In this paper, we describe our work on extending password managers towards automatic password change on the web. The main idea is that users can teach the password managers how to change their password on a specific website using a recorder module and share this information (blueprints) with other users, effectively crowdsourcing the creation of these blueprints. Parts of the proposal were implemented as an add-on for the Firefox browser and evaluated in a user study. Our results show that our proposal is viable and usable
A fast method for the retrieval of integrated longwave and shortwave top-of-atmosphere upwelling irradiances from MSG/SEVIRI (RRUMS)
A new Rapid Retrieval of Upwelling irradiances from MSG/SEVIRI (RRUMS) is presented. It has been developed to observe the top-of-atmosphere irradiances of small scale and rapidly changing features that are not sufficiently resolved by specific Earth radiation budget sensors. Our retrieval takes advantage of the spatial and temporal resolution of MSG/SEVIRI and provides outgoing longwave and reflected shortwave radiation only by means of a combination of SEVIRI channels. The longwave retrieval is based on a simple linear combination of brightness temperatures from the SEVIRI infrared channels. The shortwave retrieval is based on a neural network that requires as input the visible and near-infrared SEVIRI channels
The Gas Flow in the Loop Seals of a Dual Circulating Fluidized Bed: Splitting of the Fluidizing Agent and Gas Leakage through the Loop Seals
Modeling of Carbon Black Fragmentation During High‐Intensity Dry Mixing Using the Population Balance Equation and the Discrete Element Method
A complex interaction between the process design and the properties of carbon black (CB) during dry mixing of cathode material influences the microstructure and thus the performance of the Li-ion battery. The description of these interactions by means of a coupling of the mixing process simulation and the fragmentation of CB is the focus of this work. The discrete element method provides information about the frequency and intensity of the stress. The change of the CB size distribution is done by the population balance equation. The material strength as well as the fracture behavior are represented with simple models. The calibration of the model parameters is performed using the Nelder–Mead algorithm. The calibrated models provide good agreement with the measurements of the size distributions from experimental investigations. Transfer of the calibrated parameters to other process settings is possible and provides good agreement in some cases. Recalibration of the fracture behavior improves the accuracy of the model so that it can be used as a predictive tool
Detailed Comparison of DNS to PSE for Oblique Breakdown at Mach 3
A pair of oblique waves at low amplitudes is introduced in a supersonic flat-plate boundary layer. Their downstream development and the concomitant process of laminar to turbulent transition is then investigated numerically using Direct Numerical Simulations (DNS) and Parabolized Stability Equations (PSE). This abstract is the last part of an extensive study of the complete transition process initiated by oblique breakdown at Mach 3. In contrast to the previous simulations, the symmetry condition in the spanwise direction is removed for the simulation presented in this abstract. By removing the symmetry condition, we are able to confirm that the flow is indeed symmetric over the entire computational domain. Asymmetric modes grow in the streamwise direction but reach only small amplitude values at the outflow. Furthermore, this abstract discusses new time-averaged data from our previous simulation CASE 3 and compares PSE data obtained from NASA's LASTRAC code to DNS results
- …