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Data Visceralization: Enabling Deeper Understanding of Data Using Virtual Reality
No full textPaper presented at IEEE VIS 2020Award winner : InfoVis Best Paper Honorable MentionInternational audienceA fundamental part of data visualization is transforming data to map abstract information onto visual attributes. While this abstraction is a powerful basis for data visualization, the connection between the representation and the original underlying data (i.e., what the quantities and measurements actually correspond with in reality) can be lost. On the other hand, virtual reality (VR) is being increasingly used to represent real and abstract models as natural experiences to users. In this work, we explore the potential of using VR to help restore the basic understanding of units and measures that are often abstracted away in data visualization in an approach we call data visceralization. By building VR prototypes as design probes, we identify key themes and factors for data visceralization. We do this first through a critical reflection by the authors, then by involving external participants. We find that data visceralization is an engaging way of understanding the qualitative aspects of physical measures and their real-life form, which complements analytical and quantitative understanding commonly gained from data visualization. However, data visceralization is most effective when there is a one-to-one mapping between data and representation, with transformations such as scaling affecting this understanding. We conclude with a discussion of future directions for data visceralization
Inferring number of populations and changes in connectivity under the n-island model
No full textCorrection to: Heredity https://doi.org/10.1038/s41437-021-00426-9, published online 12 April 2021.International audienceInferring the demographic history of species is one of the greatest challenges in populations genetics. This history is often represented as a history of size changes, thus ignoring population structure. Alternatively, structure is defined a priori as a population tree and not inferred. Here we propose a framework based on the IICR (Inverse Instantaneous Coalescence Rate), which can be estimated using the PSMC method of Li and Durbin (2011) for a single diploid individual. For an isolated population, the IICR matches the population size history, which is how the PSMC outputs are generally interpreted. However, it is increasingly acknowledged that the IICR is a function of the demographic model and sampling scheme. Our automated method fits observed IICR curves of diploid individuals with IICR curves obtained under piecewise-stationary symmetrical island models, in which we assume a fixed number of time periods during which gene flow is constant. We infer the number of islands, their sizes, the periods at which connectivity changes and the corresponding rates of connectivity. Validation with simulated data showed that the method can accurately recover most of the scenario parameters. Our application to a set of five human PSMCs yielded demographic histories that are in agreement with previous studies using similar methods and with recent research suggesting ancient human structure. They are in contrast with the widely accepted view of human evolution consisting of one ancestral population branching into three large continental and panmictic populations with varying degrees of connectivity and no population structure within each continent
The effect of efficiency enhancement in international air cargo processing on improving national logistics competitiveness and its financial impact on the airport operator
No full textAir cargo transport plays an essential role in social and economic development, accounting for more than 35% of the global commercial value while handling only 0.5% of the total volume traded. This productivity lever contributes significantly to economic development, and vice versa. The main drivers for air freight growth are economic growth, globalization, and interdependent logistics strategies, such as lean, just-in-time and custom production, which have been enhanced by e-commerce. According to two of the major aircraft companies, air freight is projected to grow at 3.3-4.1% rate annually for the next 18-20 years, reinforcing the need for efficiency, sustainability, and strategic planning to keep infrastructure expansion and operational costs at healthy levels. Cargo handling plays a special role in most of international airport hubs around the world, contributing for an important part of their economic and financial results, representing, sometimes – like the Manaus International Airport case, more than 50% of their annual revenue (49,7% in 2019 and 64,5% in 2020). Planning a considerable modernization of the processes and computerized systems involved in the air cargo control, the Receita Federal do Brasil and the Secretariat of Foreign Trade have developed the new model of Cargo and Traffic Control - Air Mode (CCT-Aéreo), which will be implemented in the Single Foreign Trade Portal - Siscomex. That system aims to reduce the need of physical documentation and personnel interference of RFB and other Brazilian authorities that work directly in the import cargo processes, resulting in a more efficient protocol, which intends to reduce cargo terminal handling and storage costs for the import industry. Although this import cost reduction is desirable from a national competitiveness point of view and will probably bring many benefits in the long-term attracting new import partners and goods, we observed significant shortcomings in the understanding of the cargo terminals financial results through scenario simulations. Since they are the main responsible for the infrastructure and service provision needed for handling cargo and dealing with public authorities, a significant amount of investment was done throughout time to comply with national regulations – which requires time for amortization. The simulations, elaborated with a horizontal analysis basis methodology, revealed that cargo terminals might be highly impacted in the short term if the CCT goals are achieved, provoking new discussions about eventual compensations or a better planned transition time for airport operators
Liberalization and the Brazilian Market Experience: the case of São Gonçalo do Amarante Airport
No full textThe legal rights and obligations of States concerning the provision of air navigation services were established in the Chicago Convention. The airspace's structure and operation are an exclusive competence of each State, complying with basic technical rules established by the International Civil Aviation Organization (ICAO). The major Air Navigation Service Providers (ANSP) have a monopoly position in their countries. Then, these providers do not have reason to improve their performance. The ANSPs often operate more focused on policy targets rather than answering to the needs of their customers. Currently, a period known as globalization promotes changes in nationalist structures and interconnects nations economically and socially. This process made changes in the ownership and management structure of airports developed since the late 1970s. Private participation and privatization of airports began in the 1980s, gained thrust in the late 1990s and early 2000s, and slowed down in the late 2000s. In Brazil, this process began 2011 with the airport's concession program. In the case of the provision of air navigation services, the rule allowed new companies to provide the services. In most other States, air navigation services continue to be State-owned, and in others, it opens to liberalization. For the first time in Brazil, the government granted an airport with Control Tower Service. It was the first concession and experience. The operations with private management started in 2014, but in 2020 the company asked to give back the asset. In this work, this case will be analyzed
A study on UAS countermeasure by simulating a jammer on Guarulhos airport no-fly-zone
No full textUnmanned Aircraft Systems (UAS) have their origins at the begging of the 20th century. Following the airplane invention, in 1903, military forces from different countries started to study a way to combine radio-control in a pilotless aircraft to be used as a weapon in WWI and WWII. Up to the 1960s, these systems were developed only for military combat and espionage intentions. However, the transistor technology created a breakthrough miniaturizing radio component and made available small-scale aircraft radio-controlled to civil customers, which became the beginning of aeromodelling. The evolution of electronic and telecommunication technologies, high-speed communication networks, digital cameras, powerful lithium-ion batteries, and chipsets turned UAS into more powerful weapons and more useful instruments for civilian applications. As it became cheaper and more popular, problems involving airspace control started to arise. Commercial pilots reported year by year an increase in UAS sighting near airports. In Brazil, Guarulhos airport and Congonhas airport had to interrupt operations several times due to not authorized UAS flights near their runway threshold positions. The content of this work researches UAS classification, regulations, and countermeasures technologies looking for solutions to increase the safety of flights near Guarulhos airport. In the end, an RF simulation investigates the effectiveness of a simple WiFi jammer proposed solution
Global Impact Criteria for Assessing the Perturbation of an Air Traffic Control Radar by a Wind Farm
No full textInternational audienc
Parabolic Set Simulation for Reachability Analysis of Linear Time Invariant Systems with Integral Quadratic Constraint
No full textInternational audienceThis work extends reachability analyses based on ellipsoidal techniques to Linear Time Invariant (LTI) systems subject to an integral quadratic constraint (IQC) between the past state and disturbance signals , interpreted as an input-output energetic constraint. To compute the reachable set, the LTI system is augmented with a state corresponding to the amount of energy still available before the constraint is violated. For a given parabolic set of initial states, the reachable set of the augmented system is overapproximated with a time-varying parabolic set. Parameters of this paraboloid are expressed as the solution of an Initial Value Problem (IVP) and the overapproximation relationship with the reachable set is proved. This paraboloid is actually supported by the reachable set on so-called touching trajectories. Finally , we describe a method to generate all the supporting paraboloids and prove that their intersection is an exact characterization of the reachable set. This work provides new practical means to compute overapproximation of reachable sets for a wide variety of systems such as delayed systems, rate limiters or energy-bounded linear systems
Producing Human Factor Recommendations in the Aviation Sector
No full textInternational audienceThis paper explores how Human Factors (HF) recommendations for the design of systems, the design of equipment and the design of operations are produced in the Aviation Sector. It also investigates to what extent they rely on the use of HF methods available in the literature. The paper builds on semi-directive interviews from HF experts and practitioners in several Aviation Organizations in Europe and beyond. The interviews captured real HF intervention practices that are described based on actual design examples. The paper presents an overview of practices used amongst the Aviation Industry to generate HF design recommendations within different organizations collaborating on a common European Project. It discusses how HF experts and practitioners produce efficient HF recommendations, and what is needed not only in terms of methods to carry out these recommendations but also and possibly more importantly that which is required from a broader organizational perspective
SmartCoop Algorithm: Improving Smartphones Position Accuracy and Reliability through Collaborative Positioning
No full textInternational audienceIn recent years, our society has been preparing for a paradigm shift toward the hyper-connectivity of urban areas. This highly anticipated rise of connected smart city centers is led by the development of low-cost connected smartphone devices owned by each one of us. In this context, the demand for low-cost, high-precision localization solutions is driven by the development of novel autonomous systems. The creation of a collaborative network will take advantage of the large number of connected devices in today's city center. This paper validates the positioning performance increase of Android low-cost smartphones device present in a collaborative network. The assessment will be made on both simulated and collected smartphone's GNSS raw data measurements. We propose a collaborative method based on the estimation of distances between network mobile users contributing to a SMARTphone COOPerative Positioning algorithm (SmartCoop). Previous analysis made on smartphone data allow us to generate simulated data for experimenting our cooperative engine in nominal conditions. The evaluation and analysis of this innovative method shows a significant increase of accuracy and reliability of smartphones positioning capabilities. Position accuracy improves by more than 3m, in average, for all smartphones within the collaborative network