21,145 research outputs found

    Inflation Persistance and Credibility in Turkey During the Nineties

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    This study assesses the credibility of disinflation programs in Turkey during the nineties, where several programs of reform took place. We investigate the credibility of these policies building on a previous research made by Agenor and Taylor (1993). The model is based on two assumptions: (i) inflation is a serially correlated process; (ii) the definition of a proxy that is able to measure the degree of credibility of a programme. The empirical results show that there was a sharp loss of credibility at the end of the 1991 and at the beginning of the 1994 and during the Asian crisis. The Program that the Central Bank implemented after the crisis was able to increase the level of credibility of the CBRT policies. Loss of credibility is registered during the end of the 1995, while various political events took place and during the 1997 following the world economic conditions and the outflow of capitals

    An extensive and autonomous deep space navigation system using radio pulsars

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    Interstellar navigation poses significant challenges in all aspects of a spacecraft. One of them is reliable, low-cost, real-time navigation, especially when there is a considerable distance between Earth and the spacecraft in question. In this paper, a complete system for navigation using pulsar radio emissions is described and analysed. The system uses a pulsar‟s emissions in the radio spectrum to create a novel system capable of fully autonomous navigation. The system is roughly divided into two parts, the front - end and the back - end, as well as their subdivisions. The front - end performs initial signal reception and pre-processing. It applies time-based coherent de-dispersion to allow for low-power on-board processing, and uses a very wide bandwidth to limit the required antenna size. As a result, the electronics required performing the processing is complex, but the system is well limited in both size and power consumption

    State Estimation for the Individual and the Population in Mean Field Control with Application to Demand Dispatch

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    This paper concerns state estimation problems in a mean field control setting. In a finite population model, the goal is to estimate the joint distribution of the population state and the state of a typical individual. The observation equations are a noisy measurement of the population. The general results are applied to demand dispatch for regulation of the power grid, based on randomized local control algorithms. In prior work by the authors it has been shown that local control can be carefully designed so that the aggregate of loads behaves as a controllable resource with accuracy matching or exceeding traditional sources of frequency regulation. The operational cost is nearly zero in many cases. The information exchange between grid and load is minimal, but it is assumed in the overall control architecture that the aggregate power consumption of loads is available to the grid operator. It is shown that the Kalman filter can be constructed to reduce these communication requirements,Comment: To appear, IEEE Trans. Auto. Control. Preliminary version appeared in the 54rd IEEE Conference on Decision and Control, 201

    Correction of upstream flow and hydraulic state with data assimilation in the context of flood forecasting

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    The present study describes the assimilation of river water level observations and the resulting improvement in flood forecasting. The Kalman Filter algorithm was built on top of a one-dimensional hydraulic model which describes the Saint-Venant equations. The assimilation algorithm folds in two steps: the first one was based on the assumption that the upstream flow can be adjusted using a three-parameter correction; the second one consisted of directly correcting the hydraulic state. This procedure was applied using a four- day sliding window over the flood event. The background error covariances for water level and discharge were repre- sented with anisotropic correlation functions where the cor- relation length upstream of the observation points is larger than the correlation length downstream of the observation points. This approach was motivated by the implementation of a Kalman Filter algorithm on top of a diffusive flood wave propagation model. The study was carried out on the Adour and the Marne Vallage (France) catchments. The correction of the upstream flow as well as the control of the hydraulic state during the flood event leads to a significant improve- ment in the water level and discharge in both analysis and forecast modes

    Time-Varying Nairu and Real Interest Rates in the Euro Area. ENEPRI Working Paper No. 24, October 2003

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    This paper analyses the Nairu in the euro area and the influence that monetary policy had on its development. Using the Kalman-filter technique we find that the Nairu has varied considerably since the early 1970s. The Kalman-filter technique is applied here for the first time using explicit exogenous variables. In particular, real interest rates were found to explain a quarter of the increase in the Nairu between 1980 and 1995. This indicates the possibility of a long-run nonsuperneutrality of monetary policy

    SUBSTANTIATION OF THE PUBLIC DEBT SUSTAINABILITY USING KALMAN FILTER

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    Global economic conditions have pushed many countries into the delicate situation of contracting foreign loans, leading overnight at alarming volumes of public debt. The need for control and relevant analysis for the sustainability of a country\'s public debt has led us to use the Kalman filter in predicting future values of the key indicators of public debt. The development of a mathematical model of analysis for public services and the budget deficit was necessary to objectively assess the level of the public debt sustainability.Knowing future values of the public debt or the future evolutions of the revenues for the operational budget, offers the posibility of a better handling of the operational expenditures and finally a better balance for the public budget deficit.Using the mathematical mechanism of Kalman filters implemented in Matlab programming language, we generated the estimated future values of the proposed model proposed and key indicators, the results confirming the fears of a low public debt sustainability for Romania.We predicted the future values for the debt service, the public external debt and the operational public revenues,expenditures and deficit, and compared them, to obtain an image of the future evolution and position of the sustainability of the public debt. The work in this paper is an innovative one for the public science sector, and the results obtained are promising for future researches. The values estimated by the Kalman filter are an orientation for the future public policies, and indicate a rather stable but negative evolution for the public debt service. The sustainability of the public debt depends on the decisions taken for the correction of the estimated values, in changing the negative evolution of the budgetary indicators into a positive one.Taking all this into consideration we will conclude that the mathematical mecanism of the Kalman filters offers valuable informations for Government and future research should be oriented to develop it's returned results.Kalman filter, debt, sustainability, deficit, prediction
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