João Barroso

Bio: João Barroso is an academic researcher from University of Trás-os-Montes and Alto Douro. The author has contributed to research in topics: Computer science & Usability. The author has an hindex of 20, co-authored 190 publications receiving 1508 citations. Previous affiliations of João Barroso include Instituto Superior de Engenharia do Porto & Complutense University of Madrid.

Electronic white cane for blind people navigation assistance

Abstract: In modern daily life people need to move, whether in business or leisure, sightseeing or addressing a meeting. Often this is done in familiar environments, but in some cases we need to find our way in unfamiliar scenarios. Visual impairment is a factor that greatly reduces mobility. Currently, the most widespread and used means by the visually impaired people are the white stick and the guide dog; however both present some limitations. With the recent advances in inclusive technology it is possible to extend the support given to people with visual impairment during their mobility. In this context we propose a system, named SmartVision, whose global objective is to give blind users the ability to move around in unfamiliar environments, whether indoor or outdoor, through a user friendly interface that is fed by a geographic information system (GIS). In this paper we propose the development of an electronic white cane that helps moving around, in both indoor and outdoor environments, providing contextualized geographical information using RFID technology.

Number plate reading using computer vision

Abstract: The main tasks of a number plate recognition system are the location of the number plate area in the image, the segmentation of the characters and their identification. These tasks are strongly inter-related, mainly because the way to check if the number plate has been correctly located is based on the result of the character identification process (it should correspond to a predefined syntax). Algorithmic improvements to previous versions of the system, based on the results of intensive testing, are described in this paper. For the location of the number plate area in the image, a new line-based method has been developed. The method, instead of looking for character like shapes in the image, takes advantage of the "signature" of the number plate area in a horizontal cross-section of the image. The method used for the segmentation of the characters is derived from a technique first proposed by Lu (1995). The identification of the characters uses the OCR engine developed by Barroso et al. (1995), based on the critical points method.

The SmartVision Navigation Prototype for Blind Users

Abstract: The goal of the Portuguese project "SmartVision: active vision for the blind" is to develop a small, portable and cheap yet intelligent and reliable system for assisting the blind and visually impaired while navigating autonomously, both in- and outdoor. In this article we present an overview of the prototype, design issues, and its different modules which integrate GPS and Wi-Fi localisation with a GIS, passive RFID tags, and computer vision. The prototype addresses global navigation for going to some destiny, by following known landmarks stored in the GIS in combination with path optimisation, and local navigation with path and obstacle detection just beyond the reach of the white cane. The system does not replace the white cane but complements it, in order to alert the user to looming hazards. In addition, computer vision is used to identify objects on shelves, for example in a pantry or refrigerator. The user-friendly interface consists of a four-button hand-held box, a vibration actuator in the handle of the white cane, and speech synthesis. In the near future, passive RFID tags will be complemented by active tags for marking navigation landmarks, and speech recognition may complement or substitute the vibration actuator.

[Expression of fusion proteins in beta(2)GP I gene-transfected HEp-2 cells and its clinical application].

Abstract: OBJECTIVE To establish an indirect immunofluorescent test so as to improve the sensitivity and specificity of examination of antibodies to beta(2)-glycoprotein METHODS Full-length beta(2)GP cDNA was obtained from human hepatocellular cancer cell line HepG2 by RT-PCR and cloned into the mammalian expression vector pEGFP-C1 The recombinant plasmid pEGFP-beta(2)GP was transfected into HEp-2 cells RT-PCR, immunoblotting (IBT), confocal fluorescence microscopy, and indirect immunofluorescent test (IIF) were used to confirm the expression, localization, and antigenicity of fusion protein of green fluorescent protein (GFP) Serum specimens from 19 patients suspected as with secondary antiphospholipid syndrome (APS), 1 patient diagnosed as with primary APS, and 10 normal persons were detected with IIF-IgG-beta(2)GP1, ELISA-IgG-ACL, and ELISA-IgG-beta(2)GP I simultaneously RESULTS (1) The HEp-beta(2)GP I cells thus obtained retained their ability of expression of beta(2)GP-I-GFP for more than ten generations This beta(2)GP-I-GFP showed the antigenicity of beta(2)GP-I with a characteristic feature (2) Seven of the 20 serum specimens from APS patients showed characteristic immunofluorescent pattern No serum specimen from normal persons showed immunofluorescent staining The comparison of results of the three methods showed that the concordance between IIF-IgG-beta(2)GP I and ELISA-IgG-beta(2)GP I was the most perfect (Kappa = 0886) (3) HEp-beta(2)GP I retained the immunofluorescent property of HEp-2 cell CONCLUSION As a new kind of substrate of IIF, beta(2)GP I transfectant can be used to detect anti-beta(2)GP-I antibodies Transfeted HEp-2 cells keep the immunofluorescent property of HEp-2 cells in IFANA test and can be used as substrate for routine IFANA detection

Automatic License Plate Recognition (ALPR): A State-of-the-Art Review

Abstract: Automatic license plate recognition (ALPR) is the extraction of vehicle license plate information from an image or a sequence of images. The extracted information can be used with or without a database in many applications, such as electronic payment systems (toll payment, parking fee payment), and freeway and arterial monitoring systems for traffic surveillance. The ALPR uses either a color, black and white, or infrared camera to take images. The quality of the acquired images is a major factor in the success of the ALPR. ALPR as a real-life application has to quickly and successfully process license plates under different environmental conditions, such as indoors, outdoors, day or night time. It should also be generalized to process license plates from different nations, provinces, or states. These plates usually contain different colors, are written in different languages, and use different fonts; some plates may have a single color background and others have background images. The license plates can be partially occluded by dirt, lighting, and towing accessories on the car. In this paper, we present a comprehensive review of the state-of-the-art techniques for ALPR. We categorize different ALPR techniques according to the features they used for each stage, and compare them in terms of pros, cons, recognition accuracy, and processing speed. Future forecasts of ALPR are given at the end.

License Plate Recognition From Still Images and Video Sequences: A Survey

Abstract: License plate recognition (LPR) algorithms in images or videos are generally composed of the following three processing steps: 1) extraction of a license plate region; 2) segmentation of the plate characters; and 3) recognition of each character This task is quite challenging due to the diversity of plate formats and the nonuniform outdoor illumination conditions during image acquisition Therefore, most approaches work only under restricted conditions such as fixed illumination, limited vehicle speed, designated routes, and stationary backgrounds Numerous techniques have been developed for LPR in still images or video sequences, and the purpose of this paper is to categorize and assess them Issues such as processing time, computational power, and recognition rate are also addressed, when available Finally, this paper offers to researchers a link to a public image database to define a common reference point for LPR algorithmic assessment

시력 손상과 시각 장애(Visual Impairment and Blindness)

Abstract: Acting Under Secretary of Health requested that a working group be established to develop the Veterans Health Initiative (VHI). He envisioned this as a comprehensive program to recognize the connection between certain health effects and military service, to allow military history to be better documented, to prepare health care providers to better serve their veteran patients, and to establish a data base for further study. This was first discussed by the Acting Under Secretary in relation to the health of former prisoners of war. Development was really begun by the former Chief Academic Affairs Officer, Dr. David Stevens, with the Military Service History project. This involves a pocket card for medical residents detailing the important components of a military service history targeting the health risks associated with various periods of service and more generic issues of concern and a website containing references relevant to the issues. Educational modules in the Veterans Health Initiative VHA will assist health care providers in recognizing the connection between certain health effects and military service, prepare health care providers to better serve veteran patients, and will provide a data base for further study. This independent study is designed to provide primary care practitioners with an introduction to the pathologies that lead to sight loss, their functional implications, appropriate method of referrals, training programs, and special considerations for interactions with visually impaired individuals. After completing this independent study, participants would be able to: • Define legal blindness; • Describe the causes of sight loss; • Delineate the functional implications of vision loss • Delineate the psycho/social impact of vision loss on the veteran; • Outline the role of the Visual Impairment Services Team (VIST) in the treatment of legally blind veterans and the referral process; • Describe the special personal and environmental considerations needed for visually impaired patients; • Describe the special medical considerations needed for visually impaired patients; • Describe the primary care practitioner's role in assisting veterans in establishing well-grounded claims for disability related to the loss of vision; and • Describe compensation and pension benefits provided for veterans with eye disabilities. After completing this independent study, you should 1. be able to: state the definition of legal blindness; 2. be able to: associate eye diseases with their visual implications; 3. be able to: demonstrate insight into the functional and Psycho/Social implications of sight-loss; 4. know when referrals to VIST are indicated; 5. understand …