Foreign Exchange Intervention and Equilibrium Real Exchange Rates

Monetary authorities intervene in the currency markets in order to pursue a monetary rule and/or to smooth exchange rate volatility caused by speculative attacks. In the present paper we investigate for possible intervention effects on the volatility of nominal exchange rates and the estimated equilibrium behaviour of real exchange rates. The main argument of the paper is that omission of intervention effects -when they are significant- would bias the ability to detect any PPP-based behaviour of the real exchange rates in the long run. Positive evidence for this argument comes from the experience of six Central and Eastern European economies, whose exchange markets are characterised by frequent interventions.Foreign Exchange Market Intervention; Real Exchange Rates; PPP.

State-Space Quantization Design for the Suboptimal Control of Constrained Systems Using Neuromorphic Controllers

During the last few years there has been considerable interest in the use of trainable controllers based upon the use of neuron-like elements, with the expectation being that these controllers can be trained, with relatively little effort, to achieve good performance. However, good performance hinges on the ability of the neural net to generate a "good" control law even when the input does not belong to the training set, and it has been shown that neural-nets do not necessarily generalize well. It has been proposed that this problem can be solved by essentially quantizing the state-space and then using a neural-net to implement a table look-up procedure. However, there is little information on the effect of this quantization upon the controllability properties of the system. In this paper we address this problem by extending the theory of control of constrained systems to the case where the controls and measured states are restricted to finite or countably infinite sets. These results provide the theoretical framework for recently suggested neuromorphic controllers but they are also valuable for analyzing the controllability properties of computer-based control systems

Men's experience of anger: a study on anger and pluralistic qualitative methods

The present study is a phenomenological exploration of the way men in London make sense of their experiences of anger. Data were collected from British online resources as well as individual interviews; and were analysed using Thematic Analysis, Discursive Psychology and Interpretative Phenomenological Analysis. The aim was to explore how the emotional state of anger is comprehended by adult males living in London. In order to inform the exploration, the social and biological dimensions were taken into consideration, framing the discursive construction of their understanding of the emotional experience. The results reveal individual tensions but also agreement on the main dimensions of anger experience, detection, understanding and expression. These are then applied to a critical evaluation of how the U.K.’s social constructs around anger and the angry person are presented in the participants’ accounts and how the participants address these constructs; as well as to a theorizing of what a person is and how the emotional experience makes one think about themselves after the experience is over. The study contributes to ongoing debates about how emotions are experienced and understood by the person; how they are used to explain and justify his/her way of-seeing and way-of-being in the world; and how discourse and experience interact with one-another. Moreover, it is an exercise in the combination of qualitative methods of analysis

Testing Long-Run Purchasing Power Parity under Exchange Rate Targeting

The present paper exploits the idea that empirical estimates of the long-run PPP relationship may compound two distinct influences coming from the behavior of market participants and policy makers when the latter are targeting the exchange rate. This tends to bias tests of long-run PPP against its acceptance. The validity of the theoretical arguments is assessed by drawing on the experience of two European Union countries, Greece and France for the post-Bretton Woods period. Estimation biases due to the omission of policy effects are found to be significant only in the case of Greece. For France, our test results provide evidence bearing on the effectiveness of the competitive disinflation strategy pursued by the French authorities.Long-run PPP; exchange rate targeting; intervention policy; multivariate cointegration

Norm Based Optimally Robust Control of Constrained Discrete Time Linear Systems

Most realistic control problems involve both some type of time-domain constraints and model uncertainty. However, the majority of controller design procedures currently available focus only on one aspect of the problem, with only a handful of method capable of simultaneously addressing, albeit in a limited fashion, both issues. In this paper we propose a simple design procedure that takes explicitly into account both time domain constraints and model uncertainty. Specifically, we use a operator norm approach to define a simple robustness measure for constrained systems. The available degrees of freedom are then used to optimize this measure subject to additional performance specifications. We believe that the results presented here provide a useful new approach for designing controllers capable of yielding good performance under substantial uncertainty while meeting design constraints

Two different methodologies for geoid determination from ground and airborne gravity data

In this study, two methodologies are investigated for geoid determination from ground and airborne gravity data. These two methodologies depend on the downward continuation method used. The first is the inverse Poisson integral; the second is the normal free-air gradient. Each of the two methods requires different treatment of the terrain effects and in turn different approaches to determine the geoid. The two geoid solutions, from ground data, are compared with existing GPS/levelling benchmarks and it is found that the second method gives a better fit due to the bias introduced from the inverse Poisson integral. The same process was applied to the airborne data, but with additional processing, that is the filtering of the terrain effects to preserve the consistency of the data due to the filtering of the airborne data. A study on the effect of filtering was also carried out in this paper and it concluded that filtering the terrain effects has no impact on the geoid. In addition, the airborne data, filtered to three different cut-off frequencies, were used to compute the geoid to investigate the possibility of using the denser data, of lower accuracy, to determine a high-resolution geoid. Even though the data filtered to small cut-off frequency have poorer agreement with the ground data, the geoids computed from the different filtered data is the nearly the sam

Blow-up of the hyperbolic Burgers equation

The memory effects on microscopic kinetic systems have been sometimes modelled by means of the introduction of second order time derivatives in the macroscopic hydrodynamic equations. One prototypical example is the hyperbolic modification of the Burgers equation, that has been introduced to clarify the interplay of hyperbolicity and nonlinear hydrodynamic evolution. Previous studies suggested the finite time blow-up of this equation, and here we present a rigorous proof of this fact

Optimization of Tetrapolar Impedance Electrodes in Microfluidic Devices for Point of Care Diagnostics using Finite Element Modeling

Electrophoresis is widely applied in the field of biochemistry and molecular biology. Tetrapolar electrical impedance sensing (TEIS) has been shown capable of replacing the conventional detection technology in order to develop a point of care electrophoretic analyzer. Besides the advantages of reduced influence of electrode polarization, TEIS is affected by sensitivity distribution depending on the electrode design. A well reported practice outside of electrophoresis, systematic investigation of the effects of sensitivity distribution on the TEIS in microfluidic devices has not been conducted. Here we utilize finite element modeling, backed by experimental results, to optimize the sensor design within an electrophoretic separation device. Numerous sensor designs were validated regarding detectability, sensitivity and spatial resolution. The results show, that minimizing the distance between the central/pick-up electrodes increases sensitivity and spatial resolution whereas the distance between the central electrodes and the outer electrode do not influence sensitivity and spatial resolution

Single leg drop jump is affected by physical capacities in male soccer players following ACL reconstruction

Single leg drop jump (SLDJ) assessment is commonly used during the later stages of rehabilitation to identify residual deficits in reactive strength but the effects of physical capacity on kinetic and kinematic variables in male soccer players following ACL reconstruction remains unknown. Isokinetic knee extension strength, kinematics from an inertial measurement unit 3D system and SLDJ performance variables and mechanics derived from a force plate were measured in 64 professional soccer players (24.7 ± 3.4 years) prior to return to sport (RTS). SLDJ between-limb differences were measured (part 1) and players were divided into tertiles based on isokinetic knee extension strength (weak, moderate and strong) and reactive strength index (RSI) (low, medium and high) (part 2). Moderate to large significant differences between the ACL reconstructed and uninjured limb in SLDJ performance (d = 0.92 – 1.05), kinetic (d = 0.62 – 0.71) and kinematic variables (d = 0.56) were evident. Stronger athletes jumped higher (p = 0.002; d = 0.85), produced greater concentric (p = 0.001; d = 0.85) and eccentric power (p = 0.002; d = 0.84). Similar findings were present for RSI, but the effects were larger (d = 1.52 – 3.84). Weaker players, and in particular those who had lower RSI, displayed landing mechanics indicative of a “stiff” knee movement strategy. SLDJ performance, kinetic and kinematic differences were identified between-limbs in soccer players at the end of their rehabilitation following ACL reconstruction. Players with lower knee extension strength and RSI displayed reduced performance and kinetic strategies associated with increased injury risk