Implementing the macroprudential approach to financial regulation and supervision.

There is now a widespread recognition in the policy community of the need to strengthen the macroprudential orientation of financial regulatory and supervisory frameworks. At the same time, the usage of the term “macroprudential” remains ambiguous. This essay summarises the specific definition and characterisation of the term that was developed in the early 2000s at the BIS and outlines the policies needed for implementing the approach. The policies are discussed with reference to two dimensions of the approach. The first is the cross-sectional dimension and is concerned with how aggregate risk is distributed in the financial system at a given point in time. The policy issue here is how to calibrate prudential instruments so as to address common exposures across financial institutions and the contribution of each institution to system-wide tail risk. The second is the time dimension and is concerned with how aggregate risk evolves over time. The policy issue is how to dampen the inherent procyclicality of the financial system, seen as a key source of financial instability. The essay also briefly considers the implications of the adoption of a macroprudential approach for the institutional set-up.

Laboratory test for EPB tunnelling assessment:results of test campaign on two different granular soils

Earth Pressure Balanced shields are currently the most utilized tunnelling machines throughout around the world. The possibility of using conditioning agents that change the mechanical and hydraulic behaviour of a soil, changing it into a plastic paste and thus permitting soil pressure applications at the tunnel face, is the key point to explain the increasing utilization of this technology. Despite its great importance, not much laboratory researches can be registered on soil conditioning, particularly for cohesionless soils. The conditioning criterion is usually defined on the basis of a trial-and-error procedure developed directly at the job sites. A test that is able to simulate the extraction of soil from the bulk chamber with the screw conveyor inclined upwards, as in real machines, can offer a quantitative indication of the conditioned soil behavior for EPB use. The characteristics of the device and the results obtained on many different types of soil are discussed in order to point out the great importance and quality of results that can be achieved using the proposed test devic

Study of the Permeability of Foam Conditioned Soils with Laboratory Tests

EPB tunneling requires that the excavated soil has a plastic and pulpy behavior to be able to apply a stabilizing pressure to the face, but it should also be impervious to counteract filtration forces that could develop ahead of the face. The evaluation of this parameter in granular soil, before and after conditioning, is therefore of key importance for a correct conditioning agents choice. Approach: A new laboratory procedure for testing the permeability of conditioned soil with foam has been proposed. The tests have been carried out at different hydraulic loads, chosen to be 0.1 bars and 1 bar. Results: The proposed procedure has been applied to determine the behavior of differently conditioned granular soils: a fluvial sand and a pozzolanic soil and has shown that an increasing of the FIR induces a relative increase in the time required by water to pass through a standard sample, emphasizing, in this way, the effectiveness of the conditioning on impermeability of the soil. Conclusion: The tests have shown the laboratory procedure adequately captures the behavior of the conditioned soil. Further, the proposed test may also be used as an index for the preliminary definition of the quality of the soil conditioning and suitability for EPB tunnelin

Towards an Operational Framework for Financial Stability: "Fuzzy" Measurement and its Consequences

Over the last decade or so, addressing financial instability has become a policy priority. Despite the efforts made, policymakers are still a long way from developing a satisfactory operational framework. A major challenge complicating this task is the “fuzziness” with which financial (in)stability can be measured. We review the available measurement methodologies and point out several weaknesses. In particular, we caution against heavy reliance on the current generation of macro stress tests, arguing that they can lull policymakers into a false sense of security. Nonetheless, we argue that the “fuzziness” in measurement does not prevent further progress towards an operational framework, as long as it is appropriately accounted for. Crucial features of that framework include: strengthening the macroprudential orientation of financial regulation and supervision; addressing more systematically the procyclicality of the financial system; relying as far as possible on automatic stabilizers rather than discretion, thereby lessening the burden on the real-time measurement of financial stability risks; and setting up institutional arrangements that leverage the comparative expertise of the various authorities involved in safeguarding financial stability, not least financial supervisors and central banks.

The behaviour of a two-component backfilling grout used in a Tunnel-Boring Machine

The instantaneous filling of the annulus that is created behind the segment lining at the end of the tail during the TBM advance is an operation of paramount importance. Its main goal is to minimize the surface settlements due to any over-excavation generated by the passage of the TBM. To correctly achieve the goals, a simultaneous backfilling system and the injected material should satisfy the technical, operational and performance characteristics. A two-component system injection for the back-filling is progressively substituting the use of traditional mortars. In this paper different systems of back-filling grout and in particular the two-component system are analyzed and the results of laboratory tests are presented and discusse

QuaRRi: a new methodology for rock-fall risk analysis and management in quarry exploitation

Rockfall is one of the most critical geological events that can affect quarrying activities. Nevertheless, few tools are currently available to help designers and managers correctly define the risk conditions and quantify the advantages, in terms of workers' safety and quarry management, that can be obtained using suitable prevention devices. For this reason it is necessary to evaluate the various parameters that are involved, and to define the most important and which have the greatest influence on rock-fall phenomena, taking into account the Prevention through Design approach. A risk evaluation systemwhich is able to support decision makers in the critical rockfall risk assessment phase, and offer decision makers the updated information that is necessary for a continuous and dynamic operation design during exploitation activities is here presented and discusse

Galileo: the added value for integrity in harsh environments

A global navigation satellite system (GNSS)-based navigation is a challenging task in a signal-degraded environments where GNSS signals are distorted by multipath and attenuated by fading effects: the navigation solution may be inaccurate or unavailable. A possible approach to improve accuracy and availability is the joint use of measurements from different GNSSs and quality check algorithms; this approach is investigated here using live GPS and Galileo signals. A modified receiver autonomous integrity monitoring (RAIM) algorithm, including geometry and separability checks, is proposed to detect and exclude erroneous measurements: the multi-constellation approach provides redundant measurements, and RAIM exploits them to exclude distorted observations. The synergy between combined GPS/Galileo navigation and RAIM is analyzed using live data; the performance is compared to the accuracy and availability of a GPS-only solution. The tests performed demonstrate that the methods developed are effective techniques for GNSS-based navigation in signal-degraded environments. The joint use of the multi-constellation approach and of modified RAIM algorithms improves the performance of the navigation system in terms of both accuracy and availability.JRC.G.5-Security technology assessmen