Do algorithmic trading impact the quality of the United States financial market?

This paper aims to examine the effects of algorithmic trading on the market quality in the US market. Over the past decades, the introduction to sophisticated and complex algorithms into the financial sector has seduced many institutions and traders. Indeed, they are willing to pay large amount of money in research and development in order to improve their decision making of just some milliseconds. However, the rise of these new technologic tools came with some interrogations about its impact on the market quality. Many studies have been done all over the world without clearly agreeing on whether it was beneficial for the market or no. This study use aggregates values of 20 NYSE listed stocks to create a set of proxies for algorithmic trading such as the cancel-to-trade ratio, odd-lot volume ratio and trade-to-order volume ratio and analyse their relationships to another set of proxies representing the different measures of market quality (Liquidity, volatility, and price discovery). The analysis is made through a panel data regression and the findings concluded that AT proxies had a positive impact on the liquidity except for the Odd-lot volume ratio that was insignificant. The volatility in the opposite way is worsened and increased by the algorithmic trading activity. Finally, the results admit a strong positive relationship between odd-lot volume ratio and price discovery process and a strong inversely related correlation between trade-to-order volume ratio (negatively related to algorithmic trading activity) as AT proxy and the price discovery meaning that price efficiency was improved due to AT. This study draws the inference that algorithmic trading is beneficial for the market quality and its participants

Temperature-Dependent Growth of <i>Geomyces destructans</i>, the Fungus That Causes Bat White-Nose Syndrome

White-nose syndrome (WNS) is an emergent disease estimated to have killed over five million North American bats. Caused by the psychrophilic fungus Geomyces destructans, WNS specifically affects bats during hibernation. We describe temperature-dependent growth performance and morphology for six independent isolates of G. destructans from North America and Europe. Thermal performance curves for all isolates displayed an intermediate peak with rapid decline in performance above the peak. Optimal temperatures for growth were between 12.5 and 15.8°C, and the upper critical temperature for growth was between 19.0 and 19.8°C. Growth rates varied across isolates, irrespective of geographic origin, and above 12°C all isolates displayed atypical morphology that may have implications for proliferation of the fungus. This study demonstrates that small variations in temperature, consistent with those inherent of bat hibernacula, affect growth performance and physiology of G. destructans, which may influence temperature-dependent progression and severity of WNS in wild bats

Advanced European Re-Entry System Based on Inflatable Heat Shields EFESTO project overview: system and mission design and technology roadmap

European Union H2020 EFESTO project is coordinated by DEIMOS Space with the end goals of improving the European TRL of Inflatable Heat Shields for re-entry vehicles from 3 to 4/5 and pave the way to In-Orbit Demonstration that can further raise the TRL to 6. This paper presents the project objectives and provides a general overview of the latest advancements, promoting the relevance of the EFESTO know-how in the frame of a European re-entry technology roadmap. The system, aerodynamic and mission design of two Hypersonic Inflatable Aerodynamic Decelerator use case scenarios, the AVUM VEGA stage recovery and a high-mass Mars exploration EDL mission, have been selected for deriving requirements and constraints to be injected in the EFESTO ground testing phase. The focus of this phase was on the aerothermal verification of the Flexible-Thermal Protection System in the DLR Arcjet facility and the analysis of the mechanical properties of the Inflatable Structure exploiting a manufactured 1:2 demonstrator, both representing key aspects of this peculiar and innovative technology

Advanced Re-Entry Systems Based on Inflatable Heat Shields in the EFESTO Project: Preliminary IOD Mission and System Definition

The European Union H2020 project EFESTO is coordinated by DEIMOS Space with the goals of improving the TRL of Inflatable Heat Shields for re entry vehicles in Europe from 3 to 4/5 and paving the way to an In Orbit Demonstration (IOD) that could further raise the TRL to 6. This paper provides a synthesis of the EFESTO design and experimental achievements and sums up the inflatable heatshield IOD mission and system design. This is the final step of the EFESTO project. First, the initial IOD design resulted from a dedicated Concurrent Engineering Facility (CEF) session is introduced. The session core consisted of trading-off the system configuration options derived from the sequential design and testing campaigns, including the inflatable structure and F-TPS key subsystems. Additional aspects, such as launcher and landing site selection, were considered. The driving rationale is the maximization of the scientific return of the experiment while also taking into account feasibility considerations related to the current European space sector capabilities and market opportunities. The subsequent design phase focused on harmonizing the CEF mission and system definition and extending it with a preliminary assessment of the IOD system realization and mission implementation. This final output represents a unique contribution of the EFESTO project to the European know-how in inflatable heatshield technology and promotes the relevance of the EFESTO consortium in the frame of a European re-entry technology roadmap

THE EFESTO PROJECT: FLEXIBLE TPS DESIGN AND TESTING FOR ADVANCED EUROPEAN RE-ENTRY SYSTEM BASED ON INFLATABLE HEAT SHIELDS

The European Union H2020 project EFESTO has been implemented with the main objective to improve the technology readiness level (TRL) of flexible inflatable heat shields for re-entry vehicles in Europe from 3 to 4 or 5. For this purpose, two reference missions with atmospheric entry to Earth and Mars were selected. Both missions were designed to make best use of the Hypersonic Inflatable Aerodynamic Decelerator (HIAD) concept. Multidisciplinary design loops allowed prediction of the entry flight trajectory and identification of the aerothermodynamic environment on the exterior of the system. These results were the primary inputs to the design and testing of the Flexible Thermal Protection System (FTPS) layup and the underlying inflatable structure. This paper provides an insight into the efforts related to design, testing and numerical modelling of the FTPS for both applications. Advanced flexible materials were selected, some of which never had been considered in Europe before. These materials allow for a significant improvement upon previous design in system weight and maximum heat loads. Several multi-layer layups were developed for both applications, each of them allowing to keep the surface temperature below the material-specific upper limit. The most promising layups were selected for experimental simulation in DLR's arc-heated facilities LBK at flight relevant high-enthalpy conditions in realistic thermochemical environment. This testing covered both stagnation flow and tangential flow conditions in Mars and Earth atmospheres. Extensive numerical efforts were carried out to perform test rebuilding and allow cross-correlation between numerical and experimental simulations. The numerical models were calibrated with the wind tunnel data and further assisted in the analysis of the experimental results and the derivation of material specific properties and uncertainties. The project allowed to validate numerical models and simulations tools. This enables Europe to reliably design FTPS layups in future initiatives in the strategic field of re-entry solutions based on inflatable heat shields. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 821801

The EFESTO Project: Advanced European Re-Entry System based on Inflatable Heat Shield

EFESTO is a project funded by the European Union H2020 program aiming for a revamp and growth of European know-how and systems engineering capabilities in the strategic field of Inflatable Heat Shield technology for re-entry vehicles. This project analyzes the use of Inflatable Heat Shields for Mars exploration and Earth re-entry applications that served as representative study-cases. In addition to design activities at system and sub-system levels, the EFESTO team focused on testing the aerothermodynamic properties of the Flexible TPS and the mechanical characteristics of the shield, the latter exploiting a manufactured high-fidelity Inflatable Structure demonstrator. The data gathered from the two test campaigns additionally served for experimental-numerical rebuilding and cross-correlation. Finally, a phase-0 feasibility study defined a preliminary IOD mission design to enable in-flight verification and validation of the critical technologies. This paper will present the whole excursus of the project, including the key phases of use-cases survey and investigation, mission scenarios definition and analysis, system engineering and sub-system design, technology development and ground demonstration, future roadmap identification with reference IOD feasibility analysis and early definition. The project achievements have improved the European TRL of Inflatable Heat Shields from 3 to 4/5, thus paving the way towards further developments in the mid-term future. This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 821801

EFESTO - advancing European hypersonic inflatable heatshield technology for Earth recovery and Mars high-mass delivery missions

The European Union H2020 EFESTO project is coordinated by DEIMOS Space with the end goals of improving the European TRL of Inflatable Heat Shields for re-entry vehicles (from 3 to 4/5) and paving the way towards further improvements (TRL 6 with a future In-Orbit Demonstrator). This paper presents the project objectives and provides with a general overview of the activities ongoing and planned for the next two years, promoting its position in the frame of a European re-entry technology roadmap. EFESTO aims at (1) the definition of critical space mission scenarios (Earth and Mars applications) enabled by the use of advanced inflatable Thermal Protection Systems (TPS), (2) characterization of the operative environment and (3) validation by tests of both the flexible materials needed for the thermal protection (flexible thermal blanket will be tested in arcjet facility in both Earth and Martian environments) and the inflatable structure at 1:2 scale (exploring the morphing dynamics and materials response from packed to fully inflated configuration). These results will be injected into the consolidated design of a future In-Orbit Demonstrator (IOD) mission