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Vehicular Delay-Tolerant Networking (VDTN) was proposed as a new variant of a delay/disruptive-tolerant network, designed for vehicular networks. These networks are subject to several limitations including short contact durations, connectivity disruptions, network partitions, intermittent connectivity, and long delays. To address these connectivity issues, an asynchronous, store-carry-and-forward paradigm is combined with opportunistic bundle replication, to achieve multi-hop data delivery. Since VDTN networks are resource-constrained, for example in terms of communication bandwidth and storage capacity, a key challenge is to provide scheduling and dropping policies that can improve the overall performance of the network. This paper investigates the efficiency and tradeoffs of several scheduling and dropping policies enforced in a Spray and Wait routing scheme. It has been observed that these policies should give preferential treatment to less replicated bundles for a better network performance in terms of delivery ratio and average delivery delay.

The detection of fertile and ovulation periods may be performed by women’s body temperature variations. These variations are more accurate if a core-body temperature for their detection is used. Previous medical studies concluded that the use of skin temperature could be influenced by environmental conditions. Since the increasing of the body temperature in this period is only about 0.5 ºC, it is crucial that measurements should be the most accurate as possible. Due to the lack of solutions to realize that in order to measure and analyze the core-body temperature, this paper presents a system to capture, display, and monitoring core-body temperature. It is considered a hardware solution (sensor) to be placed inside cervix and a computer application to communicate and gather the collected data by the sensor. Bluetooth is used to perform the communication between a computer and the sensor. The system evaluation is performed by a medical team in several volunteer women. Furthermore, the collected data by the sensor may be used to study the relation between temperature variations and women health conditions.

Roles can be used to overcome some composition limitations in Object Oriented Languages and contribute to a better code reuse, reducing code replication and improve code maintenance. Therefore, the refactoring of legacy code to roles is an important step in maintaining and evolving this code. In this paper, we present refactorings to convert a system to roles We also present some refactorings that enable roles to be even more reusable.

The rapidly increasing popularity of WiFi has created unprecedented levels of congestion in the unlicensed frequency bands, especially in densely populated urban areas. This results mainly because of the uncoordinated operation and the unmanaged interference between WiFi access points. In this context, the main objective of this experiment is to assess the benefit of a coordinated management of radio resources in dense WiFi networks for both 2.4 GHz and 5 GHz bands, using Radio Environment Maps (REM). This experiment has used the w-iLab.t test environment and the portable test-bed provided by iMINDS for indoor scenarios. It was shown that REMs can detect the presence of interfering links on the network (co-channel or adjacent channel interference), and a suitable coordination strategy can use this information to reconfigure Access Points (AP) channel assignment and re-establish the client connection. The coordination strategy almost double the capacity of a WiFi link under strong co–channel interference, from 6.8 Mbps to 11.8 Mbps, increasing the aggregate throughput of the network from 58.7 Mbps to 71.5 Mbps. However, this gain comes with the cost of a relatively high-density network of spectrum sensors, increasing the cost of deployment. The technique of AP handoff was tested to balance the load form one AP to another, although the aggregate throughput is lower after load balancing. REMs are also capable of detecting coverage holes on the network, and a suitable Radio Resource Management strategy use this information to reconfigure the APs transmit power to reestablish the client connection and increase the throughput of the overloaded AP, at a cost of diminishing the aggregate throughput of the network. The insights coming out from this experiment helped to understand the opportunities and limitations of WiFi coordination strategies in realistic scenarios.

Reducing the gap between Software Engineering education and the needs in the software industry is a goal for Academia. Advancement in terms of cutting-edge technical skills and good soft skills preparation is the desired goal to shorten the onboarding in the labour market. Generally, in computer science or computer engineering courses, separate subjects exist to teach requirements engineering, analysis and design, coding, or validation. However, integrating all these phases normally requires experience in developing a complete project. The approach presented in this paper has involved the staff of a software company in collaboration with the staff of an academic Institution and resulted in a student's involvement in a full-stack software development project. The student was involved in an agile team composed of teachers and Information Technology (IT) professionals. Scrum framework was followed, and the product was developed using a low-code development platform. Results show that this agile and full stack approach allows students to develop cutting-edge technical and non- technical skills. The paper presents the approach, the achieved results, some lessons learned and some guidelines for the future.

To provide the best training in software engineering, several approaches and strategies are carried out. Some of them are more theoretical, learned through books and manuals, while others have a practical focus and often done in collaboration with companies. In this paper, we share an approach based on a balanced mix to foster the assimilation of knowledge, the approximation with what is done in software companies and student motivation. Two questionnaires were also carried out, one involving students, who had successfully completed the subject in past academic years (some had already graduated, and others are still students), and other questionnaire involving companies, in the field of software development, which employ students from our school. The analysis of the perspectives of the different stakeholders allows an overall and holistic) view, and a general understanding, of the effectiveness of the software engineering teaching approach. We analyse the results of the questionnaires and share some of the experiences and lessons learned.

Following the recent trends in software engineering regarding the growing adoption of agile methodologies and low-code development platforms, and considering the results of surveys, we carried out on students, alumni and some IT companies, we adapted the software engineering teaching of a computer engineering course to the needs and new trends of the IT industry. The Scrum methodology and the OutSystems low-code development platform were used in a project-based learning approach for teaching agile software engineering practices. This approach was complemented with the presentation and discussion of several topics during the theoretical classes, lectures given by professionals from IT companies and study visits to an IT company that uses agile methodologies and low-code platforms. This approach aims to enhance the technical skills, namely development skills on a widely used low-code platform and other software engineering skills, but also to reinforce some non-technical skills of students like teamwork and communication, today highly valued by IT companies. The first results are quite positive.