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1.
Sensors (Basel) ; 23(3)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36772580

RESUMEN

The dynamic behavior of a Powered Two-Wheeler (PTW) is much more complicated than that of a car, which is due to the strong coupling between the longitudinal and lateral dynamics produced by the large roll angles. This makes the analysis of the dynamics, and therefore the design and synthesis of the controller, particularly complex and difficult. In relation to assistance in dangerous situations, several recent manuscripts have suggested devices with limitations of cornering velocity by proposing restrictive models. However, these models can lead to repulsion by the users of PTW vehicles, significantly limiting vehicle performance. In the present work, the authors developed an Advanced Rider-cornering Assistance System (ARAS) based on the skills learned by riders running across curvilinear trajectories using Artificial Intelligence (AI) and Neural Network (NN) techniques. New algorithms that allow the value of velocity to be estimated by prediction accuracy of up to 99.06% were developed using the K-Nearest Neighbor (KNN) Machine Learning (ML) technique.

2.
J Healthc Eng ; 2021: 1342316, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628401

RESUMEN

[This corrects the article DOI: 10.1155/2020/2707560.].

4.
J Healthc Eng ; 2019: 4373760, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31281616

RESUMEN

Visibility is a very important topic in computer graphics and especially in calculations of global illumination. Visibility determination, the process of deciding which surface can be seen from a certain point, has also problematic applications in biomedical engineering. The problem of visibility computation with mathematical tools can be presented as a visibility network. Instead of utilizing a 2D visibility network or graphs whose construction is well known, in this paper, a new method for the construction of 3D visibility graphs will be proposed. Drawing graphs as nodes connected by links in a 3D space is visually compelling but computationally difficult. Thus, the construction of 3D visibility graphs is highly complex and requires professional computers or supercomputers. A new method for optimizing the algorithm visibility network in a 3D space and a new method for quantifying the complexity of a network in DNA pattern recognition in biomedical engineering have been developed. Statistical methods have been used to calculate the topological properties of a visibility graph in pattern recognition. A new n-hyper hybrid method is also used for combining an intelligent neural network system for DNA pattern recognition with the topological properties of visibility networks of a 3D space and for evaluating its prospective use in the prediction of cancer.


Asunto(s)
Bioestadística/métodos , Imagenología Tridimensional/métodos , MicroARNs , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Gráficos por Computador , Predisposición Genética a la Enfermedad , Humanos , MicroARNs/análisis , MicroARNs/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Redes Neurales de la Computación , Análisis de Secuencia de ARN
5.
Sensors (Basel) ; 18(9)2018 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-30149688

RESUMEN

This paper proposes a replicable methodology to enhance the accuracy of the photogrammetric reconstruction of large-scale objects based on the optimization of the procedures for Unmanned Aerial Vehicle (UAV) camera image acquisition. The relationships between the acquisition grid shapes, the acquisition grid geometric parameters (pitches, image rates, camera framing, flight heights), and the 3D photogrammetric surface reconstruction accuracy were studied. Ground Sampling Distance (GSD), the necessary number of photos to assure the desired overlapping, and the surface reconstruction accuracy were related to grid shapes, image rate, and camera framing at different flight heights. The established relationships allow to choose the best combination of grid shapes and acquisition grid geometric parameters to obtain the desired accuracy for the required GSD. This outcome was assessed by means of a case study related to the ancient arched brick Bridge of the Saracens in Adrano (Sicily, Italy). The reconstruction of the three-dimensional surfaces of this structure, obtained by the efficient Structure-From-Motion (SfM) algorithms of the commercial software Pix4Mapper, supported the study by validating it with experimental data. A comparison between the surface reconstruction with different acquisition grids at different flight heights and the measurements obtained with a 3D terrestrial laser and total station-theodolites allowed to evaluate the accuracy in terms of Euclidean distances.

6.
Biosensors (Basel) ; 8(3)2018 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-30011870

RESUMEN

The optimization of loading protocols following dental implant insertion requires setting up patient-specific protocols, customized according to the actual implant osseointegration, measured through quantitative, objective methods. Various devices for the assessment of implant stability as an indirect measure of implant osseointegration have been developed. They are analyzed here, introducing the respective physical models, outlining major advantages and critical aspects, and reporting their clinical performance. A careful discussion of underlying hypotheses is finally reported, as is a suggestion for further development of instrumentation and signal analysis.


Asunto(s)
Implantes Dentales , Diente/fisiología , Acelerometría , Humanos , Oseointegración , Diente/diagnóstico por imagen , Torque , Ultrasonografía
7.
Dent Mater ; 34(8): 1235-1245, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29891196

RESUMEN

OBJECTIVE: To investigate the influence of implant design on the change in the natural frequency of bone-implant system during osseointegration by means of a modal 3D finite element analysis. METHODS: Six implants were considered. Solid models were obtained by means of reverse engineering techniques. The mandibular bone geometry was built-up from a CT scan dataset through image segmentation. Each implant was virtually implanted in the mandibular bone. Two different models have been considered, differing in the free length of the mandibular branch ('long branch' and 'short branch') in order to simulate the variability of boundary conditions when performing vibrometric analyses. Modal analyses were carried out for each model, and the first three resonance frequencies were assessed with the respective vibration modes. RESULTS: With reference to the 'long branch' model, the first three modes of vibration are whole bone vibration with minimum displacement of the implant relative to bone, with the exception of the initial condition (1% bone maturation) where the implant is not osseointegrated. By contrast, implant displacements become relevant in the 'short branch' model, unless osseointegration level is beyond 20%. The difference between resonance frequency at whole bone maturation and resonance frequency at 1% bone maturation remained lower than 6.5% for all modes, with the exception of the third mode of vibration in the 'D' implant where this difference reached 9.7%. With reference to the 'short branch', considering the first mode of vibration, 61-68% of the frequency increase was achieved at 10% osseointegration; 72-79% was achieved at 20%; 89-93% was achieved at 50% osseointegration. The pattern of the natural frequency versus the osseointegration level is similar among different modes of vibration. SIGNIFICANCE: Resonance frequencies and their trends towards osseointegration level may differ between implant designs, and in different boundary conditions that are related to implant position inside the mandible; tapered implants are the most sensitive to bone maturation levels, small implants have very little sensitivity. Resonance frequencies are less sensitive to bone maturation level beyond 50%.


Asunto(s)
Implantes Dentales , Diseño de Prótesis Dental , Retención de Prótesis Dentales , Interfase Hueso-Implante , Simulación por Computador , Diseño Asistido por Computadora , Materiales Dentales/química , Análisis del Estrés Dental/métodos , Análisis de Elementos Finitos , Oseointegración/fisiología , Análisis de Frecuencia de Resonancia , Tomografía Computarizada por Rayos X , Vibración
8.
Dent Mater ; 34(3): 460-469, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29395470

RESUMEN

OBJECTIVE: To assess the influence of implant thread shape and inclination on the mechanical behaviour of bone-implant systems. The study assesses which factors influence the initial and full osseointegration stages. METHODS: Point clouds of the original implant were created using a non-contact reverse engineering technique. A 3D tessellated surface was created using Geomagic Studio® software. From cross-section curves, generated by intersecting the tessellated model and cutting-planes, a 3D parametric CAD model was created using SolidWorks® 2017. By the permutation of three thread shapes (rectangular, 30° trapezoidal, 45° trapezoidal) and three thread inclinations (0°, 3° or 6°), nine geometric configurations were obtained. Two different osseointegration stages were analysed: the initial osseointegration and a full osseointegration. In total, 18 different FE models were analysed and two load conditions were applied to each model. The mechanical behaviour of the models was analysed by Finite Element (FE) Analysis using ANSYS® v. 17.0. Static linear analyses were also carried out. RESULTS: ANOVA was used to assess the influence of each factor. Models with a rectangular thread and 6° inclination provided the best results and reduced displacement in the initial osseointegration stages up to 4.58%. This configuration also reduced equivalent VM stress peaks up to 54%. The same effect was confirmed for the full osseointegration stage, where 6° inclination reduced stress peaks by up to 62%. SIGNIFICANCE: The FE analysis confirmed the beneficial effect of thread inclination, reducing the displacement in immediate post-operative conditions and equivalent VM stress peaks. Thread shape does not significantly influence the mechanical behaviour of bone-implant systems but contributes to reducing stress peaks in the trabecular bone in both the initial and full osseointegration stages.


Asunto(s)
Interfase Hueso-Implante/fisiología , Implantes Dentales , Diseño de Prótesis Dental , Oseointegración/fisiología , Fenómenos Biomecánicos , Simulación por Computador , Análisis de Elementos Finitos , Programas Informáticos
9.
Appl Bionics Biomech ; 2017: 9701762, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29410600

RESUMEN

This paper deals with additive manufacturing techniques for the creation of 3D fetal face models starting from routine 3D ultrasound data. In particular, two distinct themes are addressed. First, a method for processing and building 3D models based on the use of medical image processing techniques is proposed. Second, the preliminary results of a questionnaire distributed to future parents consider the use of these reconstructions both from an emotional and an affective point of view. In particular, the study focuses on the enhancement of the perception of maternity or paternity and the improvement in the relationship between parents and physicians in case of fetal malformations, in particular facial or cleft lip diseases.

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