Step count algorithm adapted to indoor localization

This paper presents a step count algorithm designed to work in real-time using low computational power. This proposal is our first step for the development of an indoor navigation system, based on Pedestrian Dead Reckoning (PDR). We present two approaches to solve this problem and compare them based in their error on step counting, as well as, the capability of their use in a real time system.

Traveled Distance Estimation Algorithm for Indoor Localization

This paper presents an ankle mounted Inertial Navigation System (INS) used to estimate the distance traveled by a pedestrian. This distance is estimated by the number of steps given by the user. The proposed method is based on force sensors to enhance the results obtained from an INS. Experimental results have shown that, depending on the step frequency, the traveled distance error varies between 2.7% and 5.6%.

Person Localization Using Sensor Information Fusion

Nowadays the incredible grow of mobile devices market led to the need for location-aware applications. However, sometimes person location is difficult to obtain, since most of these devices only have a GPS (Global Positioning System) chip to retrieve location. In order to suppress this limitation and to provide location everywhere (even where a structured environment doesn’t exist) a wearable inertial navigation system is proposed, which is a convenient way to track people in situations where other localization systems fail. The system combines pedestrian dead reckoning with GPS, using widely available, low-cost and low-power hardware components. The system innovation is the information fusion and the use of probabilistic methods to learn persons gait behavior to correct, in real-time, the drift errors given by the sensors.

Localization system for pedestrians based on sensor and information fusion

Nowadays there is an increase of location-aware mobile applications. However, these applications only retrieve location with a mobile device's GPS chip. This means that in indoor or in more dense environments these applications don't work properly. To provide location information everywhere a pedestrian Inertial Navigation System (INS) is typically used, but these systems can have a large estimation error since, in order to turn the system wearable, they use low-cost and low-power sensors. In this work a pedestrian INS is proposed, where force sensors were included to combine with the accelerometer data in order to have a better detection of the stance phase of the human gait cycle, which leads to improvements in location estimation. Besides sensor fusion an information fusion architecture is proposed, based on the information from GPS and several inertial units placed on the pedestrian body, that will be used to learn the pedestrian gait behavior to correct, in real-time, the inertial sensors errors, thus improving location estimation.

Low cost inertial-based localization system for a service robot

Dissertation presented at Faculty of Sciences and Technology of the New University of Lisbon to attain the Master degree in Electrical and Computer Science Engineering

Cerebral Sinovenous Thrombosis in Children: Clinical Presentation and Extension, Localization and Recanalization of Thrombosis

Many important questions regarding pathophysiology and treatment of cerebral sinovenous thrombosis need clarification and may depend on further knowledge on the etiology, site, extension and recanalization of the thrombosis. We studied these variables in a cohort of children and adolescents from seven Portuguese Centers. We conclude from our results that the deep venous system and the superior longitudinal sinus are less frequently affected with thrombosis but have a greater potential for serious neurologic disease and for major sequelae. Non-recanalization, at least in the long term, is not an adverse prognostic factor. Extensive propagation of the thrombus from the initial site of origin seems to be common. The early identification of risk factors and their treatment coupled with an aggressive attitude towards diagnosis and treatment for thrombosis involving the deep venous system would be warranted.

Adaptation and Localization of Open Source ERPs - The case of Parties in OFBiz

O software tem vindo a tornar-se uma parte importante de qualquer empresa, cobrindo várias áreas funcionais, tais como manufaturação, vendas ou recursos humanos. O facto de uma empresa possuir um software capaz de ligar todas ou a maior parte das suas áreas funcionais e de acomodar as suas regras de negócio permite que estas tenham acesso a dados em tempo real nos quais se podem basear para tomar decisões. Estes tipos de software podem ser categorizados como Enterprise resource planning (ERP). Tendo em conta que estes tipos de software têm um papel importante dentro de uma empresa, a aquisição dos mesmos é algo que deve ser bem estudado. As grandes empresas normalmente optam pela aquisição de soluções comerciais uma vez que estas tendem a ter mais funcionalidades, maior suporte e certificações. Os ERPs comerciais representam, no entanto, um esforço elevado para que a sua compra possa ser feita, o que limita a possibilidade de aquisição dos mesmos por parte de pequenas ou médias empresas. No entanto, tal como acontece com a maior parte dos tipos de software, existem alternativas open-source. Se nos colocássemos na posição de uma pequena empresa, a tentar iniciar o seu negócio em Portugal, que tipo de ERP seria suficiente para os nossos requisitos? Teríamos que optar por comprar uma solução comercial, ou uma solução open-source seria suficiente? E se optássemos por desenvolver uma solução à medida? Esta tese irá responder a estas questões focando-se apenas num dos componentes base de qualquer ERP, a gestão de entidades. O componente de gestão de entidades é responsável por gerir todas as entidades com as quais a empresa interage abrangindo colaboradores, clientes, fornecedores, etc. A nível de funcionalidades será feita uma comparação entre um ERP comercial e um ERP open-source. Como os ERPs tendem a ser soluções muito genéricas é comum que estes não implementem todos os requisitos de um negócio em particular, como tal os ERPs precisam de ser extensíveis e adaptáveis. Para perceber até que ponto a solução open-source é extensível será feita uma análise técnica ao seu código fonte e será feita uma implementação parcial de um gerador de ficheiros de auditoria requerido pela lei Portuguesa, o SAF-T (PT). Ao estudar e adaptar a solução open-source podemos especificar o que teria que ser desenvolvido para podermos criar uma solução à medida de raiz.

Combining WLAN fingerprint-based localization with sensor data for indoor navigation using mobile devices

This project proposes an approach for supporting Indoor Navigation Systems using Pedestrian Dead Reckoning-based methods and by analyzing motion sensor data available in most modern smartphones. Processes suggested in this investigation are able to calculate the distance traveled by a user while he or she is walking. WLAN fingerprint- based navigation systems benefit from the processes followed in this research and results achieved to reduce its workload and improve its positioning estimations.

Probabilistic constraint reasoning with Monte Carlo integration to robot localization

This work studies the combination of safe and probabilistic reasoning through the hybridization of Monte Carlo integration techniques with continuous constraint programming. In continuous constraint programming there are variables ranging over continuous domains (represented as intervals) together with constraints over them (relations between variables) and the goal is to find values for those variables that satisfy all the constraints (consistent scenarios). Constraint programming “branch-and-prune” algorithms produce safe enclosures of all consistent scenarios. Special proposed algorithms for probabilistic constraint reasoning compute the probability of sets of consistent scenarios which imply the calculation of an integral over these sets (quadrature). In this work we propose to extend the “branch-and-prune” algorithms with Monte Carlo integration techniques to compute such probabilities. This approach can be useful in robotics for localization problems. Traditional approaches are based on probabilistic techniques that search the most likely scenario, which may not satisfy the model constraints. We show how to apply our approach in order to cope with this problem and provide functionality in real time.

Marine toxins in bivalves: accumulation, kinetics and subcellular responses

Sociedade Polis Litoral Ria Formosa,Projects Quasus and Project Toxigest financed by PROMAR (2007-2013)

Crystallographic studies of proteins involved in the mRNA localization mechanisms in Drosophila melanogaster and amidation of the peptidoglycan residues in Staphylococcus aureus

Part of the work described in this chapter, was the subject of the following publication: D. Vieira, T. a. Figueiredo, A. Verma, R. G. Sobral, A. M. Ludovice, H. de Lencastre, and J. Trincao, “Purification, crystallization and preliminary X-ray diffraction analysis of GatD, a glutamine amidotransferase-like protein from Staphylococcus aureus peptidoglycan,” Acta Crystallogr. Sect. F Struct. Biol. Commun., vol. 70, no. 5, pp. 1–4, Apr. 2014.

Study of the role of wall teichoic acids in the localization Staphylococcus aureus cell wall synthesis protein PBP4

The cell wall of Staphylococcus aureus is a highly complex network mainly composed of highly cross-linked peptidoglycan (PG) and teichoic acids (TAs), both important for the maintenance of the integrity and viability of bacteria. The penicillin binding proteins (PBPs), which catalyse the final stage of PG biosynthesis, are targets of β-lactam antibiotics and have been a key focus of antibacterial research. S. aureus has four native PBPs, PBP1-4 carried by both methicillin-sensitive (MSSA) and –resistant (MRSA) strains. PBP4 is required for the synthesis of the highly cross-linked PG and, as shown in recent studies, is essential for the expression of β-lactam resistance in community-acquired strains (CA-MRSA). This protein has a septal localization that seems to be spatially and temporally regulated by an unknown intermediate of the wall teichoic acids (WTA) biosynthesis pathway. Therefore, if WTA synthesis is compromised, PBP4 becomes dispersed throughout the entire cell membrane. The aim of this project was to identify the WTA precursor responsible for the septal recruitment of PBP4. In order to do so, inducible mutants of tarB and tarL genes in the background of NCTCPBP4-YFP were constructed allowing for the study of PBP4 localization in the presence and absence of these specific tar genes.With this work we were able to show that the absence of TarB or TarL leads to the delocalization of PBP4, indicating that TarL or a protein/WTA precursor whose localization/synthesis is dependent on TarL is responsible for the recruitment of PBP4.

Localization in underground tunnels

Positioning technologies are becoming ubiquitous and are being used more and more frequently for supporting a large variety of applica- tions. For outdoor applications, global navigation satellite systems (GNSSs), such as the global positioning system (GPS), are the most common and popular choice because of their wide coverage. GPS is also augmented with network-based systems that exploit existing wireless and mobile networks for providing positioning functions where GPS is not available or to save energy in battery-powered devices. Indoors, GNSSs are not a viable solution, but many applications require very accurate, fast, and exible positioning, tracking, and navigation functions. These and other requirements have stim- ulated research activities, in both industry and academia, where a variety of fundamental principles, techniques, and sensors are being integrated to provide positioning functions to many applications. The large majority of positioning technologies is for indoor environments, and most of the existing commercial products have been developed for use in of ce buildings, airports, shopping malls, factory plants, and similar spaces. There are, however, other spaces where positioning, tracking, and navigation systems play a central role in safety and in rescue operations, as well as in supporting speci c activities or for scienti c research activities in other elds. Among those spaces are underground tunnels, mines, and even underwater wells and caves. This chapter describes the research efforts over the past few years that have been put into the development of positioning systems for underground tun- nels, with particular emphasis in the case of the Large Hadron Collider (LHC) at CERN (the European Organization for Nuclear Research), where localiza- tion aims at enabling more automatic and unmanned radiation surveys. Examples of positioning and localization systems that have been devel- oped in the past few years for underground facilities are presented in the fol- lowing section, together with a brief characterization of those spaces’ special conditions and the requirements of some of the most common applications. Section 5.2 provides a short overview of some of the most representative research efforts that are currently being carried out by many research teams around the world. In addition, some of the fundamental principles and tech- niques are identi ed, such as the use of leaky coaxial cables, as used at the LHC. In Section 5.3, we introduce the speci c environment of the LHC and de ne the positioning requirements for the envisaged application. This is followed by a detailed description of our approach and the results that have been achieved so far. Some last comments and remarks are presented in a nal section.

Spectrum-based energy leak localization

Dissertação de Mestrado em Engenharia Informática