Parametric Surfaces for Augmented Architecture representation

Augmented Reality (AR) represents a growing communication channel, responding to the need to expand reality with additional information, offering easy and engaging access to digital data. AR for architectural representation allows a simple interaction with 3D models, facilitating spatial understanding of complex volumes and topological relationships between parts, overcoming some limitations related to Virtual Reality. In the last decade different developments in the pipeline process have seen a significant advancement in technological and algorithmic aspects, paying less attention to 3D modeling generation. For this, the article explores the construction of basic geometries for 3D model’s generation, highlighting the relationship between geometry and topology, basic for a consistent normal distribution. Moreover, a critical evaluation about corrective paths of existing 3D models is presented, analysing a complex architectural case study, the virtual model of Villa del Verginese, an emblematic example for topological emerged problems. The final aim of the paper is to refocus attention on 3D model construction, suggesting some "good practices" useful for preventing, minimizing or correcting topological problems, extending the accessibility of AR to people engaged in architectural representation

The Virtual Element Method with curved edges

In this paper we initiate the investigation of Virtual Elements with curved faces. We consider the case of a fixed curved boundary in two dimensions, as it happens in the approximation of problems posed on a curved domain or with a curved interface. While an approximation of the domain with polygons leads, for degree of accuracy $k \geq 2$, to a sub-optimal rate of convergence, we show (both theoretically and numerically) that the proposed curved VEM lead to an optimal rate of convergence

Recent Studies of Nonequilibrium Flows at the Cornell Aeronautical Laboratory

Vibrational relaxation in supersonic nozzle diatomic gas flow, nonequilibrium effects in high enthalpy airflow over thick wedge flat plates, and reentry nonequilibrium flow field

Spectrum-line reversal measurements of free electron and coupled N2 vibrational temperature in expansion flows

Spectrum line reversal measurements of free electron and coupled nitrogen vibrational temperatures in expansion flow of shock tub

Governance of securities clearing and settlement systems

In the context of securities clearing and settlement systems, the nature of governance arrangements acquires a dimension that goes beyond their traditional function in corporate law. They constitute a tool for regulators and central banks to achieve their respective policy goals relating to market operation, market integrity, and systemic stability. In the light of the analysis of this paper, and pending a further evolution in the regulation of securities clearing and settlement in the Community, the following conclusions can be drawn. Whatever the model of corporate governance used in a jurisdiction, securities clearing and settlement systems should adopt and ensure effective implementation of the highest corporate governance standards or best practices adopted or recommended for companies in the jurisdiction in which it operates as such standards or practices evolve over time. Generally, this would imply that securities clearing and settlement systems at minimum should adopt and implement the best practices recommended for listed companies. Additionally, a securities clearing or settlement system should adopt corporate governance mechanisms adequate to address the interests of users and the public in the operation of the system. Such mechanisms should be organized so that the criteria followed to select participants on the board or on specialized committees are established ex ante. Board members should also take into account the interests of users and the public in board decisions, in particular, those relating to qualifications for system access, fair pricing, the integrity of the risk management system, innovation and efficiency, and the achievement of the policy objectives of competent authorities. Securities clearing and settlement systems should make adequate disclosures regarding their corporate governance arrangements so that users and the public can ascertain the manner in which conflicts of interest among owners, the board, users and the public interest are prevented, resolved or mitigated. Corporate governance arrangements of securities clearing and settlement systems should be the subject of adequate regulation and oversight to ensure that services are provided at fair prices to users under fair and equitable conditions of access; that the risk management programs of system operators are effective; that risk management decisions are not affected by considerations extraneous to the risk management function; and that, to the maximum extent possible, functional service providers compete in equivalent conditions of competition. Looking forward, the adoption of a harmonized regulatory regime for securities clearing and settlement systems should be considered to complete the internal market within the Community and to better achieve the policy goals identified in this paper relating to the governance of those systems.clearing, settlement, governance, risk management, oversight.

A unified IMEX Runge-Kutta approach for hyperbolic systems with multiscale relaxation

In this paper we consider the development of Implicit-Explicit (IMEX) Runge-Kutta schemes for hyperbolic systems with multiscale relaxation. In such systems the scaling depends on an additional parameter which modifies the nature of the asymptotic behavior which can be either hyperbolic or parabolic. Because of the multiple scalings, standard IMEX Runge-Kutta methods for hyperbolic systems with relaxation loose their efficiency and a different approach should be adopted to guarantee asymptotic preservation in stiff regimes. We show that the proposed approach is capable to capture the correct asymptotic limit of the system independently of the scaling used. Several numerical examples confirm our theoretical analysis