Abstract
In underwater navigation, sonars are useful sensing devices for operation in confined or structured environments, enabling the detection and identification of underwater environmental features through the acquisition of acoustic images. Nonetheless, in these environments, several problems affect their performance, such as background noise and multiple secondary echoes. In recent years, research has been conducted regarding the application of feature extraction algorithms to underwater acoustic images, with the purpose of achieving a robust solution for the detection and matching of environmental features. However, since these algorithms were originally developed for optical image analysis, conclusions in the literature diverge regarding their suitability to acoustic imaging. This article presents a detailed comparison between the SURF (Speeded-Up Robust Features), ORB (Oriented FAST and Rotated BRIEF), BRISK (Binary Robust Invariant Scalable Keypoints), and SURF-Harris algorithms, based on the performance of their feature detection and description procedures, when applied to acoustic data collected by an autonomous underwater vehicle. Several characteristics of the studied algorithms were taken into account, such as feature point distribution, feature detection accuracy, and feature description robustness. A possible adaptation of feature extraction procedures to acoustic imaging is further explored through the implementation of a feature selection module. The performed comparison has also provided evidence that further development of the current feature description methodologies might be required for underwater acoustic image analysis.

Abstract
It has been a quarter of a century since the publication of the first edition of the IEEE International Conference on Computer Supported Cooperative Work in Design (CSCWD) held in 1996 in Beijing, China. Despite some attempts to empirically examine the evolution and identity of the field of CSCW and its related communities and disciplines, the scarcity of scientometric studies on the IEEE CSCWD research productivity is noteworthy. To fill this gap, this study reports on an exploratory quantitative analysis of the literature published in the IEEE CSCWD conference proceedings with the purpose of visualizing and understanding its structure and evolution for the 2001-2019 period. The findings offer valuable insights into the paper and author distribution, country and citation-level productivity indicators, degree of collaboration, and collaboration index. Through this analysis we also expect to get an initial overview of the IEEE CSCWD conference concerning the main topics being presented, most cited papers, and variances in the number of keywords, full-text views, and references.

Abstract
Antibiotics are widely applied for the treatment of humans and animals, being the Sulfonamides a special group. The presence of antibiotics in the aquatic environment causes the development antibiotic-resistant bacteria, which is related to the emerging of untreatable infectious diseases. One of the most common methods for determine it consists in high-performance liquid chromatography coupled with mass spectrom-etrym, which is not suitable for an in situ analysis strategy. One important property of sulfonamides is how the compound reacts when added the colorimetric reagent p-dimethylaminocinnamaldehyde, opening the possibility of using colorimetry to measure the concentration. To allow an analysis on the field, the solution needs to be fully mobile and practical. In this context, we recently developed a new screening method based on a computational application running over a picture of the sample; however, despite this approach improving the analysis process when compared to traditional methods, it is still not fully mobile. Smartphones’ computational capabilities are increasing and more powerful than many laptops of older generations. Taking this into account, we developed a mobile analysis application that leverages the computing power and ease of use of a smartphone. The acquired picture will pass through a color correction algorithm to normalize the capture considering the environmental lighting. When the algorithm finishes processing the image, the app will return the estimated concentration of the sample. This approach enables in situ analysis, without requiring an Internet connection nor specific analysis equipment, and the ability to have a rather precise guess of the level of contamination of any water. © Springer Nature Switzerland AG 2021.

Abstract
Byzantine fault tolerant (BFT) protocols are designed to increase system dependability and security. They guarantee liveness and correctness even in the presence of arbitrary faults. However, testing and validating BFT systems is not an easy task. As is the case for most concurrent and distributed applications, the correctness of these systems is not solely dependant on algorithm and protocol correctness. Ensuring the correct behaviour of BFT systems requires exhaustive testing under real-world scenarios. An approach is to use fault injection tools that deliberate introduce faults into a target system to observe its behaviour. However, existing tools tend to be designed for specific applications and systems, thus cannot be used generically. We argue that more advanced and powerful tools and frameworks are needed for testing the security and safety of distributed applications in general, and BFT systems in particular. Specifically, a fault injection framework that can be integrated into both client and server side applications, for testing them exhaustively. We present ZERMIA, a modular and extensible fault injection framework, designed for testing and validating concurrent and distributed applications. We validate ZERMIA’s principles by conduction a series of experiments on a distributed applications and a state of the art BFT library, to show the benefits of ZERMIA for testing and validating applications. © 2021, Springer Nature Switzerland AG.

Abstract

Abstract
Since children are far more vulnerable than adults to the effects of air pollution and spend about a third of their day in school, strict control of indoor environments in educational buildings is paramount to prop-erly identify, manage and mitigate putative environmental risks for children. In this context, this work aimed to provide a holistic view on the outcomes obtained from the national ARIA project, which was focused on broadening the knowledge on the effects on children's health of the exposure to schools' indoor air. In particular, this work performed a comprehensive investigation of the indoor air quality (IAQ) in 20 public primary schools located in Porto (Northern Region, Portugal). This paper presents the results of the investigation along with the recently published main outcomes of ARIA on (1) the char-acteristics of the environment surrounding the surveyed buildings, and (2) the school's environment-related health effects in school-age children from the studied classrooms. The investigation consisted in an extensive assessment plan conducted in 71 classrooms to assess temperature, relative humidity, carbon monoxide and dioxide, particulate matter (PM2.5, PM10, and ultrafine particles), nitrogen dioxide, ozone, volatile organic compounds, formaldehyde, acetaldehyde, airborne fungi, bacteria and endotoxins, and investigate their respective sources, during the cold seasons of 2014-2015. A series of studies was also launched to investigate school environment-related health detriments in 916 children. The results showed that comfort and ventilation issues and/or indoor pollutant levels that exceeded recommended limits were found in a substantial number of the classrooms surveyed. The high density of occupants, deficient ventilation, soil characteristics, presence of indoor pollution sources (e.g. classroom materials and consumer products) and outdoor pollution were some of the factors that seemed to explain the high air stuffiness and/or indoor pollution load identified in classrooms. In fact, some of indoor pollutants detected, even at low exposure levels, were associated with the development of respiratory symptoms in school-age children. Moreover, results from this work have also shown that the characteristics of the environment surrounding the schools, namely the presence of green spaces and species richness, can be major determinants of respiratory health among school-age children. Overall, the body of evidence generated from the ARIA project can support new evidence-based perspectives for promotion of health in educational buildings.