Cookies Policy
The website need some cookies and similar means to function. If you permit us, we will use those means to collect data on your visits for aggregated statistics to improve our service. Find out More
Accept Reject
  • Menu
Publications

Publications by CRIIS

2014

CDM controller order and disturbance rejection ability

Authors
Coelho, João Paulo; Giernacki, Wojciech; Boaventura-Cunha, José;

Publication
ICCIT 2014: International Conference on Control and Information Technology

Abstract
The coefficient diagram method is primarily an algebraic control design method whose objective is to easily obtain a good controller with minimum user effort. As a matter of fact, if a system model, in the form of linear differential equations, is known, the user only need to define a time-constant and the controller order. The later can be established regarding the expected disturbance type via a lookup table first published by Koksal and Hamamci in 2004. However an inaccuracy in this table was detected and pointed-out in the present work. Moreover the above mentioned table was expanded in order to enclose any k order type disturbance

2014

Reply to: Comments on "Particle Swarm Optimization with Fractional-Order Velocity"

Authors
Tenreiro Machado, JAT; Solteiro Pires, EJS; Couceiro, MS;

Publication
NONLINEAR DYNAMICS

Abstract

2014

Optimal Operation Point in Electrical Grids using a MOPSO Algorithm

Authors
Pereira, P; Leitao, S; Solteiro Pires, EJS;

Publication
2014 SIXTH WORLD CONGRESS ON NATURE AND BIOLOGICALLY INSPIRED COMPUTING (NABIC)

Abstract
The paper presents a study about optimal supply of the energy service, using simulations of network operation scenarios, in order to optimize resources and minimize the variables: operation cost, energy losses, generation cost and consumers shedding. These simulations create optimal operation models of the network, allowing the system operator obtain knowledge to take pre-established procedures that must be performed in situations of contingency in order to forecast and minimize drawbacks. The simulations were performed using a multiobjective particle swarm optimization algorithm. The algorithm was applied to the IEEE 14 Bus network where the optimal power flow was evaluated by the MATPOWER tool to establish an optimal electrical working model to minimize the associated costs.

2014

Teaching Fourier Series Expansions in Undergraduate Education with the Help of the FouSE Android Application

Authors
Reis, MC; Soares, S; Cardeal, S; Morais, R; Peres, E; Ferreira, PJSG;

Publication
iJIM

Abstract
This paper discusses the teaching of Fourier Series concepts in undergraduate Electrical Engineering education with the help of an Android application, especially developed to that end. In order to better understand the links and implications, some of the basic Fourier series theory is briefly reviewed. The Android application has an easy-to-use, friendly interface, conceived to help undergraduate students test and assess the Fourier series expansions on a typical set of signals. The application also allows the students to control the total approximation error and the number of terms/harmonics used in the expansions. It has been found a very useful learning resource in the Fourier series context.

2014

A new electric conductance conversion method suitable for very low power applications

Authors
Miranda, N; Serodio, C; Morais, R;

Publication
MEASUREMENT

Abstract
This article describes a new electrical conductance converter method suitable for low power applications and an implementation in standard CMOS technology. Despite being designed to meet specific measurements requirements, this converter is intended for applications where device power requirements are determinative such self powered sensors networks and implantable devices. The topology is described and an implementation is presented. Results show the possibility of being powered by a single 1.2 V accumulator cell with a consumption of 8 nJ per conversion.

2014

Instrumented hip joint replacements, femoral replacements and femoral fracture stabilizers

Authors
Soares dos Santos, MPS; Ferreira, JAF; Ramos, A; Simoes, JAO; Morais, R; Silva, NM; Santos, PM; Reis, MC; Oliveira, T;

Publication
EXPERT REVIEW OF MEDICAL DEVICES

Abstract
This paper reviews instrumented hip joint replacements, instrumented femoral replacements and instrumented femoral fracture stabilizers. Examination of the evolution of such implants was carried out, including the detailed analysis of 16 architectures, designed by 8 research teams and implanted in 32 patients. Their power supply, measurement, communication, processing and actuation systems were reviewed, as were the tests carried out to evaluate their performance and safety. These instrumented implants were only designed to measure biomechanical and thermodynamic quantities in vivo, in order to use such data to conduct research projects and optimize rehabilitation processes. The most promising trend is to minimize aseptic loosening and/or infection following hip or femoral replacements or femoral stabilization procedures by using therapeutic actuators inside instrumented implants to apply controlled stimuli in the bone-implant interface.

  • 276
  • 377