Asymmetries in the Euro area economy

Using quarterly data for the period since 1987 this paper explores, in the context of a small model of the EU economy, the degree to which monetary policy has been asymmetric. It shows in particular that monetary policy has been much more responsive to threats that inflation would lie outside the price stability target than to equal sized shocks within the target zone. Similarly monetary policy has responded to threats of large positive and negative output gaps but has remained largely unresponsive to smaller divergences. It thus appears that the ECB and its predecessors have been avoiding ‘fine-tuning’ but have been aggressive in responding to substantial threats to macroeconomic stability. The action seems to have been stronger with respect to inflationary pressure than to deflation but this may offset any bias in fiscal policy. The asymmetric response of policy in part reflects considerable non-linearities and asymmetries in the behaviour of the euro area economies. High unemployment has relatively limited effect in pulling inflation down while low unemployment can be much more effective in driving it up. Economic downturns are both more rapid and sustained in driving unemployment up than recoveries are in bringing it down. There is considerable variety in these relationships and IS curves across countries, sectors and regions. Monetary policy reacts in the light of this.monetary policy, asymmetry

Asymmetries in the Euro area economy

Using quarterly data for the period since 1987 this paper explores, in the context of a small model of the EU economy, the degree to which monetary policy has been asymmetric. It shows in particular that monetary policy has been much more responsive to threats that inflation would lie outside the price stability target than to equal sized shocks within the target zone. Similarly monetary policy has responded to threats of large positive and negative output gaps but has remained largely unresponsive to smaller divergences. It thus appears that the ECB and its predecessors have been avoiding 'fine-tuning' but have been aggressive in responding to substantial threats to macroeconomic stability. The action seems to have been stronger with respect to inflationary pressure than to deflation but this may offset any bias in fiscal policy. The asymmetric response of policy in part reflects considerable non-linearities and asymmetries in the behaviour of the euro area economies. High unemployment has relatively limited effect in pulling inflation down while low unemployment can be much more effective in driving it up. Economic downturns are both more rapid and sustained in driving unemployment up than recoveries are in bringing it down. There is considerable variety in these relationships and IS curves across countries, sectors and regions. Monetary policy reacts in the light of this.monetary policy; asymmetry

A hybrid optical-wireless network for decimetre-level terrestrial positioning

Global navigation satellite systems (GNSS) are widely used for navigation and time distribution, features indispensable for critical infrastructure such as mobile communication networks, as well as emerging technologies like automated driving and sustainable energy grids. While GNSS can provide centimetre-level precision, GNSS receivers are prone to many-metre errors due to multipath propagation and obstructed view of the sky, which occur especially in urban areas where accurate positioning is needed most. Moreover, the vulnerabilities of GNSS, combined with the lack of a back-up system, pose a severe risk to GNSS-dependent technologies. Here, we demonstrate a terrestrial positioning system which is independent of GNSS and offers superior performance through a constellation of radio transmitters, connected and time-synchronised at the sub-nanosecond level through a fibre-optic Ethernet network. Employing optical and wireless transmission schemes similar to those encountered in mobile communication networks, and exploiting spectrally efficient virtual wideband signals, the detrimental effects of multipath propagation are mitigated, thus enabling robust decimetre-level positioning and sub-nanosecond timing in a multipath-prone outdoor environment. This work provides a glimpse of a future in which telecommunication networks provide not only connectivity, but also GNSS-independent timing and positioning services with unprecedented accuracy and reliability.Comment: 38 pages, 9 figures, 3 table

Milky Way Kinematics: Measurements at the Subcentral Point of the Fourth Quadrant

We use atomic hydrogen (HI) data from the Southern Galactic Plane Survey to study the kinematics of the fourth quadrant of the Milky Way. By measuring the terminal velocity as a function of longitude throughout the fourth Galactic quadrant we have derived the most densely sampled rotation curve available for the Milky Way between 3 < R < 8 kpc. We determine a new joint rotation curve fit for the first and fourth quadrants, which can be used for kinematic distances interior to the Solar circle. From our data we place new limits on the peak to peak variation of streaming motions in the fourth quadrant to be ~10 km/s. We show that the shape of the average HI profile beyond the terminal velocity is consistent with gas of three velocity dispersions, a cold component with $\Delta v=6.3$ km/s, a warmer component with $\Delta v=12.3$ km/s and a fast component with $\Delta v=25.9$ km/s. Examining the widths with Galactic radius we find that the narrowest two components show little variation with radius and their small scale fluctuations track each other very well, suggesting that they share the same cloud-to-cloud motions. The width of the widest component is constant until R<4 kpc, where it increases sharply.Comment: 36 pages, 10 figures, accepted to ApJ. Full electronic version of table 1 available at ftp://ftp.atnf.csiro.au/pub/people/nmcclure/papers/velocity_tab1.te

Dynamics of Barred Galaxies

Some 30% of disc galaxies have a pronounced central bar feature in the disc plane and many more have weaker features of a similar kind. Kinematic data indicate that the bar constitutes a major non-axisymmetric component of the mass distribution and that the bar pattern tumbles rapidly about the axis normal to the disc plane. The observed motions are consistent with material within the bar streaming along highly elongated orbits aligned with the rotating major axis. A barred galaxy may also contain a spheroidal bulge at its centre, spirals in the outer disc and, less commonly, other features such as a ring or lens. Mild asymmetries in both the light and kinematics are quite common. We review the main problems presented by these complicated dynamical systems and summarize the effort so far made towards their solution, emphasizing results which appear secure. (Truncated)Comment: This old review appeared in 1993. Plain tex with macro file. 82 pages 18 figures. A pdf version with figures at full resolution (3.24MB) is available at http://www.physics.rutgers.edu/~sellwood/bar_review.pd

Methodological considerations for the assessment of postural stability and lower limb bilateral asymmetry

Purpose: There are currently no agreed methods for the assessment of postural stability using centre of pressure (CoP) analysis of quiet standing nor assessment of lower limb bilateral asymmetry measured during a countermovement jump (CMJ). Much of the existing literature surrounding both of these biomechanical assessments are varied and inconclusive in the determination of a criterion methodology. There is also a dearth of information regarding the reliability of both measures or expected outcomes. Therefore, the purpose of the current study was twofold. Firstly, to assess the methodology and reliability of postural stability measures obtained from a force-platform. Secondly, to investigate the methodology and reliability of measuring lower limb bilateral asymmetry using a dual-force-platform set-up. Methodology: Using a repeated measures design of test-retest reliability, postural stability and CMJ performance was assessed for male (n = 10, age = 32.7 ± 9.5 yrs., height = 1.797 ± 0.060 m, mass = 88.2 ± 14.4 kg) and female (n = 9, age = 32.4 ± 8.7 yrs., height = 1.662 ± 0.055 m, mass = 70.8 ± 13.5 kg) recreationally active individuals divided into three populations, female-only (FEM), male-only (MALE) and combined (ALL). For postural stability measurement, path length (Lp), sway area (As) and mean velocity (Vm) were reported from 8 trials for six epochs derived from 100 s of quiet standing. Four trials of each condition, were conducted on each of the two separate testing days. Reliability of bilateral CMJ performance was assessed from ten maximal CMJ trials using five kinetic and two temporal neuromuscular variables: peak force (Fmax), impulse due to eccentric and concentric contraction (Jecc and Jcon), peak instantaneous mechanical power (PPO), take-off velocity (Vto), percentage of jump duration that changeover from eccentric to concentric phases occurs (tecN) and percentage of jump duration that peak force occurs (tFmaxN). Lower limb bilateral asymmetry was then calculated for Fmax, Jecc, Jcon and tFmaxN using two SIs; sided, left leg vs right leg (LvsR) and un-sided, higher vs lower limb value (HvsL) to give asymmetry irrespective of limb side. Differences between conditions and SI methods were identified using paired-samples t-tests and test-retest reliability was assessed using ICC and Bland and Altman (B&A) plot analysis. Postural Stability Results: Lp and Vm were significantly higher (p ≤ 0.05) in the EC condition for all epochs. As demonstrated differences between the two conditions, however, not always significant; in all cases of significance, As was greater in the EC condition. Absolute ICC values for Lp and Vm were indicative of excellent reliability (>0.90) however, 95% CI ranged from poor (0.75) to excellent across conditions and epochs. B&A plot analysis showed As was the most variable. In general, results showed that EC had the higher test-retest reliability, however differences between ICC values and the magnitude of the bias and LOA between conditions were small. It was not clear which epoch provided the most, or least, reliable results for Lp or Vm. For As, the 1st 30 s had the most variability, while for all variables, 90 s was one of the most reliable epochs. Cumulative moving average analysis showed a trend toward increased precision as number of repetitions increased for all epochs. Bilateral Asymmetry Results: Kinematic variables derived from analysis of a CMJ resulted in high test-retest reliability and agreement (ICC > 0.9) for Fmax, Jecc, Jcon, PPO, Vto and tecN. LvsR and HvsL methods of SI calculation were significantly different (p ≤ 0.05) for 3/4 variables. Fmax (ALL: LvsR - 0.72 ± 6.96%, HvsL 6.22 ± 3.89%), Jecc (ALL: LvsR 4.99 ± 23.47%, HvsL 25.29 ± 12.33%), Jcon (ALL: LvsR -6.93 ± 26.87%, HvsL 25.47 ± 13.80%), tFmaxN (ALL: LvsR -2.10 ± 7.87%, HvsL 5.67 ± 6.83%). Overall, the absolute ICCs of Jecc and tFmaxN ranged from poor to excellent, while Fmax and Jcon showed better agreement, although 95% CI ranges and magnitude of B&A LOAs were still large, particularly in LvsR (e.g., Fmax, ALL LvsR: Bias = 32%, LOA = 352%). B&A plot analysis demonstrated far smaller bias and LOA in HvsL than LvsR for all variables and populations. In both postural stability and bilateral asymmetry, there was no substantial differences noted between the reliability of FEM and MALE populations. For both cases, greater reliability could be seen for the majority of variables when FEM and MALE were combined in the ALL population. Conclusions: Lp and Vm had better reliability and lower variability than As. As is not recommended as a reliable postural stability performance parameter. There was a significant difference between visual conditions, indicating the impact of visual acuity on human postural control. Both EO and EC showed good reliability for all epochs, although B&A plots revealed variability in the data that should be considered in future research. Although EC appeared to be the slightly more reliable condition, it cannot be recommended over EO as they are representative of different requirements of human postural control. Bilateral CMJ performance showed good test-retest reliability, however, normalised temporal variables should be used with caution; tFmaxN was the least reliable variable. LvsR and HvsL methods of SI calculation were significantly different and have the ability to quantify very different inherent characteristics of bilateral CMJ performance. Results identify the importance of determining a suitable set of reference values and the consideration of the directionality of asymmetries on an individual basis. In a bilateral CMJ, the differences in the force generating capacity between limbs does not necessarily determine the variation in the magnitude of VGRF generated during the jump. Instead, variations in VGRF symmetry should be considered to represent bilateral variations in limb loading that stem from differing jumping and compensatory strategies adopted by individuals

Monetary Transmission in Hungary

The Hungarian Monetary Transmission Mechanism research project was expected to fill the gaps in our knowledge. Almost fifteen years after the beginning of the Hungarian transition to a market economy, we felt that the time has come to launch a comprehensive research project with the purpose of obtaining an understanding based on more solid econometric results. Our project was also motivated by the Monetary Transmission Network in the Eurosystem, which gave us the opportunity to compare the Hungarian transmission mechanism to that of the euro area. It took almost three years for the colleagues at the Bank's economics department to explore the most important areas of the transmission mechanism. The research faced several challenges. The data used for estimation are still not completely satisfactory. Moreover, the framework of monetary policy, as well as some structural features of the Hungarian economy have changed during the period under investigation. Moreover, the special characteristics of our economy required a focus somewhat different from what is usual in the literature. Due to the uneven information available regarding the various sectors and markets, it was clear from the beginning that some areas would have to receive only limited coverage, rendering the synthesis of individual results difficult. Despite these shortcomings, the empirical work presented in this volume allows us to gain a better understanding of the Hungarian monetary transmission mechanism and has thus served its stated objective well. The benefits of the project are threefold. First, it confirms our assumption about the primacy of the exchange rate channel in Hungary's small open economy. Second, there are some interesting results that may alter our thinking about how the monetary transmission works. For example, we obtained a refined and – at least compared to earlier beliefs – slightly different picture about the way consumption and investments react to monetary policy actions . Third, it brought to the fore important areas where our knowledge is far from being satisfactory. This recognition calls for further research in order to strengthen the theoretical underpinnings of our monetary policy actions. Such areas are, for example, the labour market and credit markets. We also need a deeper understanding of the factors at work determining the exchange rate. This volume collects the papers written by the project participants. The volume is structured as follows. Studies dealing with the first stages of the transmission mechanism, i.e. how the monetary policy actions are transmitted to financial markets and asset prices, are presented first. They are followed by papers estimating the macroeconomic effects of monetary policy and the behavior of aggregate demand. The last study in the volume tries to assess the potential consequences on the transmission mechanism of joining the eurozone.monetary transmission, Hungary, interest rate pass-through, monetary policy shock, exchange rate smoothing, bank-lending, structural VAR, aggregate demand, investment behavior, euro.

Optical Efficiency Calibration for Inhomogeneous IACT Arrays and a Detailed Study of the Highly Extended Pulsar Wind Nebula HESS J1825-137

Very High Energy (VHE) γ-ray astronomy using Imaging Atmospheric Cherenkov Telescopes (IACTs) is entering an era of hybrid arrays (such as H.E.S.S. II and CTA), comprising telescopes of varied specifications to enhance the accessible energy range and angular resolution. New algorithms for telescope optical efficiency calibration are developed and adapted for multi-type arrays, for both absolute light yield calibration using muons, and for relative calibration through comparison of shower images. In comparison to previous methods, the stability and flexibility of these algorithms are considerably improved. These will play an important role for the future CTA observatory. The use of multi-type IACT arrays in providing an increased understanding of astrophysical objects and environments is demonstrated through an in-depth study of the Pulsar Wind Nebula HESS J1825-137, known to be highly extended with the presence of strong energy dependent morphology. In particular, measurements of HESS J1825-137 across the entire available energy range allow the particle transport inside the nebula to be constrained, favouring advection over diffusion as the dominant mechanism. Together with X-ray data, a map of the magnetic field of the nebula can be made through spectral modelling. It will also be shown that HESS J1825-137, at 100 pc across, is one of the biggest pulsar wind nebulae to have been discovered yet