Comprehending Variability in Analysis Results of Software Product Lines

Analyses of a software product line (SPL) typically report variable results that are annotated with logical expressions indicating the set of product variants for which the results hold. These expressions can get complicated and difficult to reason about when the SPL has lots of features and product variants. Previous work introduced a visualizer that supports filters for highlighting the analysis results that apply to product variants of interest, but this work was weakly evaluated. In this paper, we report on a controlled user study that evaluates the effectiveness of this new visualizer in helping the user search variable results and compare the results of multiple variants. Our findings indicate that the use of the new visualizer significantly improves the correctness and efficiency of the user's work and reduces the user's cognitive load in working with variable results

Viewpoint: How the Graphene Could Help to Decrease SARS-CoV-2 Spread?

The COVID-19 (Coronavirus Disease 2019), caused by the SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) began in December 2019 in Wuhan, China. Until February 2021, there are 110 million of infected people, 60 million have recovered and approximately 2.5 million have passed away worldwide according to WHO. The coronavirus pandemic is evolving very rapidly and represents a risk for health care workers and society in general. Moreover, pandemic has tested the limits of health systems by raising questions about forms of prevention, management of infections with conventional therapies and the use of diagnostic tools. In this article we discussed the possible role of the nanostructured-graphene based materials as aid tools for preventing the spread and infection of SARS-CoV-2. In this regard, nanotechnology could take part in the fight against the spread of future diseases caused by deadly viruses. However, its use should be well founded in terms of biocompatibility. Therefore, we have proposed an approach based on graphene nanomaterials as possible allies for the fight against the COVID-19 spread based on the physicochemical features that present these novel nanomaterials

High integrity IMM-EKF based road vehicle navigation with low cost GPS/INS.

User requirements for the performance of GlobaL Navigation Satellite System (GNSS)-based road applications have been significantly increasing in recent years. Safety systems based on vehicle localization, electronic fee-collection systems, and traveler information services are just a few examples of interesting applications requiring onboard equipment (OBE) capable of offering a high available accurate position, even in unfriendly environments with low satellite visibility such as built-up areas or tunnels and at low cost. In addition to that, users and service providers demand from the OBEs not only accurate continuous positioning but integrity information of the reliability of this position as well. Specifically, in life-critical applications, high-integrity monitored positioning is absolutely required. This paper presents a solution based on the fusion of GNSS and inertial sensors (a Global Positioning System/Satellite-Based Augmentation System/Inertial Navigation System integrated system) running an extended Kalman filter combined with an interactive multimodel method (IMM-EKF). The solution developed in this paper supplies continuous positioning in marketable conditions and a meaningful trust level of the given solution. A set of tests performed in controlled and real scenarios proves the suitability of the proposed IMM-EKF implementation as compared with lowcost GNSS-based solutions, dead reckoning systems, single-model EKF, and other filtering approaches of the current literature.This work was supported in part by the Spanish Ministerio de Fomento under Grant FOM/3929/2005 and by the Galileo Joint Undertaking (GJU) under Grant GIROADS 332599. The Associate Editor for this paper was Y. Wang

Seaweed extracts to control postharvest phytopathogenic fungi in Rocha pear

This study was supported by the Fundação para a Ciência e a Tecnologia (FCT) to MARE (UID/MAR/04292/2020), the Associate Laboratory ARNET (LA/P/0069/2020), through national funds, and the grants to Tânia Vicente (2020.06230.BD) and Rafael Félix (SFRH/BD/139763/2018). The authors also acknowledge the support of project ORCHESTRA—add-value to ORCHards through thE full valoriSaTion of macRoalgAe (POCI-01-0247-FEDER-070155) co-funded by FEDER—Fundo Europeu de Desenvolvimento Regional da União Europeia, Portugal 2020, through COMPETE 2020—Programa Operacional Competitividade e Internacionalização, through FCT and COSMOS: Valorização biotecnológica da alga invasora Asparagopsis armata da Costa de Peniche (MAR-04.03.01-FEAMP-0370), and MACAU: Diversidade Macroalgas da reserva natural das Berlengas e costa adjacente, do conhecimento à utilização (MAR-04.03.01-FEAMP-0128) through GAL PESCA OESTE and MAR2020 in the framework of PORTUGAL2020 and the European Maritime and Fisheries Fund. C. Félix was supported by an FCT researcher contract (2021.03113.CEECIND).Fungal infections cause losses amounting to between 20 and 25% of the fruit industry’s total outcome, with an escalating impact on agriculture in the last decades. As seaweeds have long demonstrated relevant antimicrobial properties against a wide variety of microorganisms, extracts from Asparagopsis armata, Codium sp., Fucus vesiculosus, and Sargassum muticum were used to find sustainable, ecofriendly, and safe solutions against Rocha pear postharvest fungal infections. Alternaria alternata, Botrytis cinerea, Fusarium oxysporum, and Penicillium expansum mycelial growth and spore germination inhibition activities were tested in vitro with five different extracts of each seaweed (n-hexane, ethyl acetate, aqueous, ethanolic, and hydroethanolic). An in vivo assay was then performed using the aqueous extracts against B. cinerea and F. oxysporum in Rocha pear. The n-hexane, ethyl acetate, and ethanolic extracts from A. armata showed the best in vitro inhibitory activity against B. cinerea, F. oxysporum, and P. expansum, and promising in vivo results against B. cinerea using S. muticum aqueous extract were also found. The present work highlights the contribution of seaweeds to tackle agricultural problems, namely postharvest phytopathogenic fungal diseases, contributing to a greener and more sustainable bioeconomy from the sea to the farm.info:eu-repo/semantics/publishedVersio

Aplicación de modelos de redes neuronales artificiales a la determinación de movimientos en una presa bóveda.

The complexity of the dam-foundation makes difficult to interpret the records of auscultation. It is not easy to make a prognosis of the behavior of the dam in accordance with the different situations that may occur over the life of the dam. N or is it easy to interpret the deviations observed from the values estimated by numerical or statistical modeling. Neural networks offer the possibility of treating the whole dam foundation as a complex system which rules of behavior are established solely on the basis of the observed behavior without making simplifying assumptions. It has shaped the radial movement in different seasons of the pendulums available in a dam vault, which has been used as test case. We analyzed the response of the dam complex models growing. T he simplest considered only as pa r ame t e rs determining the behavior reservoir level and a moving average of ambient temperatures (simple model). In order to model applicable to any pendulum of any dam, has raised the consideration of various means mobile temperature, so that is the model itself that determines the weight of each moving average (model general). Have also been raised as da ta models that incorporate the values of the movements measured immediately prior (short-term models). The comparison of results obtained through each of the previous models of neural networks with statistical and numerical models commonly used that allows the use of neural network models useful for the interpretation of auscultation. The submission details the results obtained and the accuracy of the prognosis of each of the models studied. Models are expected to nalyze incorporate additional time variable (dynamic models), to c apture the effect of drift. This research is pa rt of the R&D financed by the Ministerio de Ciencia e Innovación: estudio de la seguridad de presas e identificación de escenarios de riesgo mediante sistemas inteligentes, reference number 048/RN08/04.5

An analysis of communication and navigation issues in collision avoidance support systems

Collision avoidance support systems (CASS) are nowadays one of the main fields of interest in the area of road transportation. Among the different approaches, those systems based on vehicle cooperation to avoid collisions present the most promising perspectives. Works available in the current literature have in common that the performance of such solutions strongly relies on the operation of two on-board subsystems: navigation and communications. However, the performance of these two subsystems is usually underestimated when the whole solution is evaluated. Collision avoidance support applications can be considered among the most critical vehicular services, and this is the reason why this paper focuses on the performance issues of these two subsystems. Main issues regarding navigation and communication performance are discussed along the paper, and a study of the literature in the field is completed with the evaluation of different system prototypes. Communication and navigation tests in real environments yield further conclusions discussed in the paper.The Authors would like to thank the Spanish Ministerio de Fomento and the Ministerio de Ciencia e Innovacion for sponsoring these research activities under the grants FOM/2454/2007, TIN2008-06441-C02-02 and AP2005-1437. Last one in frames of the FPU program. This work has been carried out inside the Intelligent Systems group of the University of Murcia, awarded as an excellence researching group in frames of the Spanish Plan de Ciencia y Tecnologıa de la Region de Murcia (04552/GERM/06)

Modelo simplificado de un depósito de almacenamiento con PCM

Este trabajo presenta un método simplificado de modelado térmico de depósitos de almacenamiento de energía térmica con materiales de cambio de fase (PCMs) en su interior. El planteamiento desarrollado es muy similar en forma y metodología al concepto de “factor de bypass”, ampliamente utilizado en el campo de la climatización para estimar las condiciones de salida de un aire tratado cuando atraviesa una batería de acondicionamiento. El método propuesto es capaz de reproducir la respuesta térmica de un depósito con PCMs de forma robusta y relativamente precisa, sólo empleando los parámetros más relevantes del almacenamiento (diez en total). Parámetros de entrada muy fundamentales y bien conocidos, ya en las primeras etapas de diseño, donde el impacto potencial de las decisiones tomadas en el ahorro de energía es el mayor, y en donde no es habitual un conocimiento perfecto de todas las particularidades del depósito con PCM (conocimiento preciso de la geometría del depósito e intercambiador, propiedades termofísicas del PCM en función de su temperatura, etc.). Para estas etapas preliminares de diseño de la instalación, el método es especialmente útil y adecuado. Los resultados obtenidos de la simulación del modelo simplificado muestran un elevado grado de convergencia y exactitud con 21 ensayos experimentales de carga y descarga térmica de dos depósitos con PCMs, observándose discrepancias en el total de energía acumulada o extraída del depósito desde valores próximos al 1% hasta como máximo un 13% aproximadamente, según ensayo y material de cambio de fase. Los dos almacenamientos latentes, usaban cada uno de ellos un PCM diferente (orgánico e inorgánico),así como un tipo de intercambiador de calor diferente (de diferente geometría, configuración y material).Los autores están especialmente agradecidos a los doctores Jorge Payá Herrero del Instituto de Ingeniería Energética de Valencia y Martin Helm del ZAE Bayern, por proporcionarnos los datos experimentales de varios procesos de carga y descarga de sus almacenamientos latentes. Estos ensayos han permitido a los autores la validación del método

Conductance Distributions in Random Resistor Networks: Self Averaging and Disorder Lengths

The self averaging properties of conductance $g$ are explored in random resistor networks with a broad distribution of bond strengths P(g)\simg^{\mu-1}. Distributions of equivalent conductances are estimated numerically on hierarchical lattices as a function of size $L$ and distribution tail parameter $\mu$. For networks above the percolation threshold, convergence to a Gaussian basin is always the case, except in the limit $\mu$ --> 0. A {\it disorder length} $\xi_D$ is identified beyond which the system is effectively homogeneous. This length diverges as $\xi_D \sim |\mu|^{-\nu}$ ($\nu$ is the regular percolation correlation length exponent) as $\mu$-->0. This suggest that exactly the same critical behavior can be induced by geometrical disorder and bu strong bond disorder with the bond occupation probability $p$$\mu$. Only lattices at the percolation threshold have renormalized probability distribution in a {\it Levy-like} basin. At the threshold the disorder length diverges at a vritical tail strength $\mu_c$ as $|\mu-\mu_c|^{-z}$, with $z=3.2\pm 0.1$, a new exponent. Critical path analysis is used in a generalized form to give form to give the macroscopic conductance for lattice above $p_c$.Comment: 16 pages plain TeX file, 6 figures available upon request.IBC-1603-01

Characterization of the K2-38 planetary system: Unraveling one of the densest planets known to date

.-- Toledo-Padrón, B. et al.Context. An accurate characterization of the known exoplanet population is key to understanding the origin and evolution of planetary systems. Determining true planetary masses through the radial velocity (RV) method is expected to experience a great improvement thanks to the availability of ultra-stable echelle spectrographs. Aims. We took advantage of the extreme precision of the new-generation echelle spectrograph ESPRESSO to characterize the transiting planetary system orbiting the G2V star K2-38 located at 194 pc from the Sun with V 11.4. This system is particularly interesting because it could contain the densest planet detected to date. Methods. We carried out a photometric analysis of the available K2 photometric light curve of this star to measure the radius of its two known planets, K2-38b and K2-38c, with Pb = 4.01593 ± 0.00050 d and Pc = 10.56103 ± 0.00090 d, respectively. Using 43 ESPRESSO high-precision RV measurements taken over the course of 8 months along with the 14 previously published HIRES RV measurements, we modeled the orbits of the two planets through a Markov chain Monte Carlo analysis, significantly improving their mass measurements. Results. Using ESPRESSO spectra, we derived the stellar parameters, Teff = 5731 ± 66, log g = 4.38 ± 0.11 dex, and [Fe/H] = 0.26 ± 0.05 dex, and thus the mass and radius of K2-38, Ma = 1.03-0.02+0.04 MaS and Ra = 1.06-0.06+0.09 RaS. We determine new values for the planetary properties of both planets. We characterize K2-38b as a super-Earth with RP = 1.54 ± 0.14 RaS and Mp = 7.3-1.0+1.1 MaS, and K2-38c as a sub-Neptune with RP = 2.29 ± 0.26 RaS and Mp = 8.3-1.3+1.3 MaS. Combining the radius and mass measurements, we derived a mean density of ρp = 11.0-2.8+4.1 g cm-3 for K2-38b and ρp = 3.8-1.1+1.8 g cm-3 for K2-38c, confirming K2-38b as one of the densest planets known to date. Conclusions. The best description for the composition of K2-38b comes from an iron-rich Mercury-like model, while K2-38c is better described by a rocky-model with H2 envelope. The maximum collision stripping boundary shows how giant impacts could be the cause for the high density of K2-38b. The irradiation received by each planet places them on opposite sides of the radius valley. We find evidence of a long-period signal in the RV time-series whose origin could be linked to a 0.25-3 MJ planet or stellar activity.With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737