Eudisley Gomes dos Anjos

Correlation between Spectral Occupancy and Packet Error Rate in IEEE 802.15.4-based Industrial Wireless Sensor Networks

This paper aims at evaluating the communication performance of the IEEE 802.15.4 standard in an industrial environment. We investigated the correlation between Packet Error Rate (PER) and Spectral Occupancy (SO) in the network environment. For this goal, we studied the impact on SO and PER resulting from the insertion of interference from other sources within the same range of the channels defined by the standard. The results show that an IEEE 802.15.4-based sensor network can suffer large drop in performance with the addition of new sources of interference. The information provided by the experiments can be used to guide the development of new spectrum-aware techniques and protocols to mitigate the interference in IEEE 802.15.4-based industrial wireless sensor networks.

The Use of Natural Interaction to Enrich the User Experience in Telemedicine Systems

Human communication always used gestures, movements and expressions as oral language support. Certain gestures are so commonly used around the world that are understood throughout different cultures and times, such as a wave or thumbs up. Natural Interaction is a way to apply this concept to user interfaces in computer systems. In this paper we discuss about the use of Natural Interaction features in a telemedicine system. More specifically, we demonstrate the use of natural interaction interfaces for control and manipulation of 3D objects inside Arthron tool. Arthron is a telemedicine tool used for surgery transmissions.

Experimental and theoretical study of a telemetric dynamic torque meter

This paper presents the development of a dynamic torque meter to be applied to rotating shafts using electronic transduction, strain gage, telemetry and LabView Graphic programming. A mathematical model was developed. The electronic transduction signal is transmitted by digital modulation from a remote transduction unit fixed to a shaft to a base station, sending the signal to a PC, by means of a VI (Virtual Instrument) developed in LabView. It can also be delivered to other units besides the PC. The use of digital modulation to transmit the radiofrequency signal, replacing conventional couplings, allows communication with a high signal/noise ratio. A clamp acts as sealant, protecting it from the environment and making it easier to install. The prototype can be used at situation that it is impossible to use flanges or sockets (the most of the industrial applications) and it is installed directly on the surface of the shaft. The use of superbatteries allows the remote unit to remain independent of a feed for several days, with long periods between maintenance. After thousands of experimental essays, the theoretical model seems to confirm the proposed idea. The system presented has a potential for high precision, low cost, long work life and easy maintenance.

Self-Powered Telemetric Torque Meter

This paper presents a self-powered telemetric torque meter. The idealized instrument uses strain gauge, telemetry, and LABVIEW graphic programming. The electronic transduction signal is transmitted by digital modulation from a remote transduction unit fixed to a rotation shaft to a base station sending signals to a personal computer (PC) by means of a virtual instrument developed in LABVIEW . The signal can also be delivered to other units besides the PC. The ZigBee/IEEE 802.15.4 protocol is the standard protocol for wireless communications and is highly used in industrial monitoring and control applications. A low-noise method for supplying the remote transduction unit components in the rotation shaft—using its rotating movement to generate the demanded energy—has also been developed. After extensive experimentation, the theoretical model seems to confirm the idea proposed. The system presented in this study is robust, precise, cost-effective, and has high-noise immunity even in abrasive and strong vibration environments.

Study on the Social Impact on Software Architecture through Metrics of Modularity

Software systems have constantly increased in size and complexity. At the same time, software architecture also grows and becomes difficult to maintain leading to failures or abandonment of systems. According to Mirroring Hypothesis (MH), the organizational structure of the development team is a mirror of software architecture. So, the importance in understanding what changes in social structure can impact in the software architecture is crucial to avoid architectural problems. This work compares modularity metrics, applied to open-source systems, with the structure of developers inside the organization. The results show the relationship between the architecture and organization and contribute to guide the evolution and maintenance of systems.

MUV-Bee: Using WSN to monitoring urban vehicles

The number of urban vehicles has increased in the past years causing innumerous problems such as traffic jams, accidents and pollution. One of the main solutions for this problem is to improve the quality of public transportation by making it more reliable, secure and efficient. In this paper, it is proposed a system for monitoring urban vehicles based on ZigBee technology, called MUV-Bee. Such system uses wireless communication to integrate the main server to public transportation buses and bus stops. Its several services provided to society allow a better quality of public transportation which make them more attractive.

Assessing maintainability metrics in software architectures using COSMIC and UML

The software systems have been exposed to constant changes in a short period of time. The evolution of these systems demands a trade-off among several attributes to keep the software quality acceptable. It requires high maintainable systems and makes maintainability one of the most important quality attributes. This paper approaches the system evolution through the analysis of potential new architectures using the evaluation of maintainability level. The goal is to relate maintainability metrics applied in the source-code of OO systems, in particular CCC, to notations defined by COSMIC methods and proposes metrics-based models to assess CCC in software architectures.

A framework for classifying and comparing software architecture tools for quality evaluation

Software quality is a crucial factor for system success. Several tools have been proposed to support the evaluation and comparison of software architecture designs. However, the diversity in focus, approaches, interfaces and results leaves the researcher and practitioner wondering what would be the most appropriate solution for their specific goals. This paper presents a comparison framework that identifies the most relevant features for categorizing different architecture evaluation tools according to six different dimensions. The results show the attributes that a comprehensive tool should support include: the ability to handle multiple modelling approaches, integration with the industry standard UML or specific ADL, support for trade-off analysis of competing quality attributes and, the reuse of knowledge through the build-up of new architectural patterns. This comparison is able to, not only guide the choice of evaluation, but also promote the development of more powerful tools for modeling and analysis of software architectures.

Systematic Mapping Studies in Modularity in IT Courses

Modularity is one of the most important quality attributes during system development. Its concepts are commonly used in disciplines of information technology courses, mainly in subjects as software project, software architecture, and others. However, it is notable among certain groups of students that this issue is not fully absorbed in a practical way. Although some researchers and practitioners have approach themes like this, there is still a lack of research about how modularity can be approached in IT courses. This paper presents a systematic mapping study about how the modularity is addressed in education. The main objective is to understand what are the main areas in this field and find more interesting points of research to improve the practice of modularity during IT disciplines.

On systems project abandonment: An analysis of complexity during development and evolution of FLOSS systems

Among all the reasons that leads to the success or failure of a Free/Libre Open Source Software (FLOSS) project, understanding the systems evolution can reveal important pieces of information to open source stakeholders, helping them to identify what can be improved in the software systems internal organization. Once software complexity is one of the most important attributes to determine software maintainability, controlling its level in the system evolution process makes the software easier to maintain, reducing the maintainability costs. Otherwise, uncontrolled complexity makes the maintenance and enhancement process lengthy, more costly and some times it can contribute to the system abandonment. This work investigates the evolution of complexity in discontinued FLOSS projects. After several analyses, the results showed that inactive FLOSS projects do not seem to be able to keep up with the extra work required to control the systems complexity, presenting a different behaviour of the successful active FLOSS projects.