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1.
Sensors (Basel) ; 23(18)2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37765879

RESUMEN

Currently, there is an increasing need for reliable mechanisms for automatically detecting and localizing people-from performing a people-flow analysis in museums and controlling smart homes to guarding hazardous areas like railway platforms. A method for detecting people using FLIR Lepton 3.5 thermal cameras and Raspberry Pi 3B+ computers was developed. The method creates a control and capture library for the Lepton 3.5 and a new person-detection technique that uses the state-of-the-art YOLO (You Only Look Once) real-time object detector based on deep neural networks. A thermal unit with an automated configuration using Ansible encapsulated in a custom 3D-printed enclosure was used. The unit has applications in simple thermal detection based on the modeling of complex scenes with polygonal boundaries and multiple thermal camera monitoring. An easily deployable person-detection and -localization system based on thermal imaging that supports multiple cameras and can serve as an input for other systems that take actions by knowing the positions of people in monitored environments was created. The thermal detection system was tested on a people-flow analysis performed in the Czech National Museum in Prague. The contribution of the presented method is the development of a small and simple detection system that is easily mountable with wide indoor as well as outdoor applications. The novelty of the system is in the utilization of the YOLO model for thermal data.

2.
Am J Med Genet A ; 188(4): 1083-1087, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34907639

RESUMEN

Zimmermann-Laband syndrome is a rare, heterogeneous disorder characterized by gingival hypertrophy or fibromatosis, aplastic/hypoplastic nails, hypoplasia of the distal phalanges, hypertrichosis, various degrees of intellectual disability, and distinctive facial features. Three genes are considered causative for ZLS: KCNH1, KCNN3, and ATP6V1B2. We report on a pair of female concordant monozygotic twins, both carrying a novel pathogenic variant in the KCNN3 gene, identified using exome sequencing. Only six ZLS patients with the KCNN3 pathogenic variant have been reported so far. The twins show facial dysmorphism, hypoplastic distal phalanges, aplasia or hypoplasia of nails, and hypertrichosis. During infancy, they showed mild developmental delays, mainly speech. They successfully completed secondary school education and are socio-economically independent. Gingival overgrowth is absent in both individuals. Our patients exhibited an unusually mild phenotype compared to published cases, which is an important diagnostic finding for proper genetic counseling for Zimmermann-Laband syndrome patients and their families.


Asunto(s)
Fibromatosis Gingival , Hipertricosis , Anomalías Múltiples , Anomalías Craneofaciales , Femenino , Fibromatosis Gingival/diagnóstico , Fibromatosis Gingival/genética , Deformidades Congénitas de la Mano , Humanos , Hiperplasia , Hipertricosis/genética , Uñas Malformadas/congénito , Fenotipo , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/genética , Gemelos Monocigóticos/genética
3.
Sci Justice ; 64(4): 421-442, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39025567

RESUMEN

In today's biometric and commercial settings, state-of-the-art image processing relies solely on artificial intelligence and machine learning which provides a high level of accuracy. However, these principles are deeply rooted in abstract, complex "black-box systems". When applied to forensic image identification, concerns about transparency and accountability emerge. This study explores the impact of two challenging factors in automated facial identification: facial expressions and head poses. The sample comprised 3D faces with nine prototype expressions, collected from 41 participants (13 males, 28 females) of European descent aged 19.96 to 50.89 years. Pre-processing involved converting 3D models to 2D color images (256 × 256 px). Probes included a set of 9 images per individual with head poses varying by 5° in both left-to-right (yaw) and up-and-down (pitch) directions for neutral expressions. A second set of 3,610 images per individual covered viewpoints in 5° increments from -45° to 45° for head movements and different facial expressions, forming the targets. Pair-wise comparisons using ArcFace, a state-of-the-art face identification algorithm yielded 54,615,690 dissimilarity scores. Results indicate that minor head deviations in probes have minimal impact. However, the performance diminished as targets deviated from the frontal position. Right-to-left movements were less influential than up and down, with downward pitch showing less impact than upward movements. The lowest accuracy was for upward pitch at 45°. Dissimilarity scores were consistently higher for males than for females across all studied factors. The performance particularly diverged in upward movements, starting at 15°. Among tested facial expressions, happiness and contempt performed best, while disgust exhibited the lowest AUC values.


Asunto(s)
Algoritmos , Reconocimiento Facial Automatizado , Expresión Facial , Humanos , Masculino , Femenino , Adulto , Reconocimiento Facial Automatizado/métodos , Adulto Joven , Persona de Mediana Edad , Imagenología Tridimensional , Procesamiento de Imagen Asistido por Computador/métodos , Identificación Biométrica/métodos , Cara/anatomía & histología , Movimientos de la Cabeza/fisiología , Postura/fisiología
4.
J Biomed Biotechnol ; 2012: 490362, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22969272

RESUMEN

Travelling is becoming available for more and more people. Millions of people are on a way every day. That is why a better control over global human transfer and a more reliable identity check is desired. A recent trend in a field of personal identification documents is to use RFID (Radio Frequency Identification) technology and biometrics, especially (but not only) in passports. This paper provides an insight into the electronic passports (also called e-passport or ePassport) implementation chosen in the Czech Republic. Such a summary is needed for further studies of biometric passports implementation security and biometric passports analysis. A separate description of the Czech solution is a prerequisite for a planned analysis, because of the uniqueness of each implementation. (Each country can choose the implementation details within a range specified by the ICAO (International Civil Aviation Organisation); moreover, specific security mechanisms are optional and can be omitted).


Asunto(s)
Identificación Biométrica/instrumentación , Identificación Biométrica/métodos , Almacenamiento y Recuperación de la Información/métodos , Dispositivo de Identificación por Radiofrecuencia/métodos , Registros , Viaje , República Checa , Humanos
5.
J Biomed Biotechnol ; 2012: 626148, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22654483

RESUMEN

There are many people who suffer from some of the skin diseases. These diseases have a strong influence on the process of fingerprint recognition. People with fingerprint diseases are unable to use fingerprint scanners, which is discriminating for them, since they are not allowed to use their fingerprints for the authentication purposes. First in this paper the various diseases, which might influence functionality of the fingerprint-based systems, are introduced, mainly from the medical point of view. This overview is followed by some examples of diseased finger fingerprints, acquired both from dactyloscopic card and electronic sensors. At the end of this paper the proposed fingerprint image enhancement algorithm is described.


Asunto(s)
Identificación Biométrica/métodos , Dermatoglifia , Aumento de la Imagen/métodos , Enfermedades de la Piel/patología , Algoritmos , Humanos , Reconocimiento de Normas Patrones Automatizadas
6.
J Imaging ; 8(5)2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35621912

RESUMEN

Finger vein recognition has evolved into a major biometric trait in recent years. Despite various improvements in recognition accuracy and usability, finger vein recognition is still far from being perfect as it suffers from low-contrast images and other imaging artefacts. Three-dimensional or multi-perspective finger vein recognition technology provides a way to tackle some of the current problems, especially finger misplacement and rotations. In this work we present a novel multi-perspective finger vein capturing device that is based on mirrors, in contrast to most of the existing devices, which are usually based on multiple cameras. This new device only uses a single camera, a single illumination module and several mirrors to capture the finger at different rotational angles. To derive the need for this new device, we at first summarise the state of the art in multi-perspective finger vein recognition and identify the potential problems and shortcomings of the current devices.

7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1980-1983, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018391

RESUMEN

Symmetry can be defined as uniformity, equivalence or exact similarity of two parts divided along an axis. While our left and right eyes clearly have a high degree of external bilateral symmetry, it is less obvious to what degree they have internal bilateral symmetry. In this paper, we try to find approximate-bilateral symmetry in retina, one of the internal parts of our eye, which plays a vital role in our vision and also can be used as a powerful biometric. Contrary to previous works, we study interretinal symmetry from a biometric perspective. In other words, we study whether the left and right retinal symmetry is strong enough to reliably tell whether a pair of the left and right retinas belongs to a single person. For this, we focus on overall symmetry of the retinas rather than specific attributes such as length, area, thickness, or the number of blood vessels. We evaluate and analyse the performance of both human and neural network based bilateral retina verification on fundus photographs. By experimenting on a publicly available data set, we confirm interretinal symmetry.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico , Fotograbar , Biometría , Humanos , Procedimientos Quirúrgicos Oftalmológicos , Retina/diagnóstico por imagen
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 2736-2739, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31946460

RESUMEN

Synthesized retinal images are highly demanded in the development of automated eye applications since they can make machine learning algorithms more robust by increasing the size and heterogeneity of the training database. Recently, conditional Generative Adversarial Networks (cGANs) based synthesizers have been shown to be promising for generating retinal images. However, cGANs based synthesizers require segmented blood vessels (BV) along with RGB retinal images during training. The amount of such data (i.e., retinal images and their corresponding BV) available in public databases is very small. Therefore, for training cGANs, an extra system is necessary either for synthesizing BV or for segmenting BV from retinal images. In this paper, we show that by using unconditional GANs (uGANs) we can generate synthesized retinal images without using BV images.


Asunto(s)
Algoritmos , Bases de Datos Factuales , Procesamiento de Imagen Asistido por Computador , Aprendizaje Automático
9.
Biomed Res Int ; 2013: 197925, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24151584

RESUMEN

This paper is devoted to new optical methods, which are supposed to be used for liveness detection on fingers. First we describe the basics about fake finger use in fingerprint recognition process and the possibilities of liveness detection. Then we continue with introducing three new liveness detection methods, which we developed and tested in the scope of our research activities--the first one is based on measurement of the pulse, the second one on variations of optical characteristics caused by pressure change, and the last one is based on reaction of skin to illumination with different wavelengths. The last part deals with the influence of skin diseases on fingerprint recognition, especially on liveness detection.


Asunto(s)
Dermatoglifia , Enfermedades de la Piel/patología , Fenómenos Fisiológicos de la Piel , Muerte , Dedos , Humanos
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