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2.
PLoS One ; 14(4): e0213918, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30943244

RESUMO

Food production in conventional agriculture faces numerous challenges such as reducing waste, meeting demand, maintaining flavor, and providing nutrition. Contained environments under artificial climate control, or cyber-agriculture, could in principle be used to meet many of these challenges. Through such environments, phenotypic expression of the plant-mass, edible yield, flavor, and nutrients-can be actuated through a "climate recipe," where light, water, nutrients, temperature, and other climate and ecological variables are optimized to achieve a desired result. This paper describes a method for doing this optimization for the desired result of flavor by combining cyber-agriculture, metabolomic phenotype (chemotype) measurements, and machine learning. In a pilot experiment, (1) environmental conditions, i.e. photoperiod and ultraviolet (UV) light (known to affect production of flavor-active molecules in edible plants) were applied under different regimes to basil plants (Ocimum basilicum) growing inside a hydroponic farm with an open-source design; (2) flavor-active volatile molecules were measured in each plant using gas chromatography-mass spectrometry (GC-MS); and (3) symbolic regression was used to construct a surrogate model of this chemistry from the input environmental variables, and this model was used to discover new combinations of photoperiod and UV light to increase this chemistry. These new combinations, or climate recipes, were then implemented in the hydroponic farm, and several of them resulted in a marked increase in volatiles over control. The process also led to two important insights: it demonstrated a "dilution effect", i.e. a negative correlation between weight and desirable chemical species, and it discovered the surprising effect that a 24-hour photoperiod of photosynthetic-active radiation, the equivalent of all-day light, induces the most flavor molecule production in basil. In this manner, surrogate optimization through machine learning can be used to discover effective recipes for cyber-agriculture that would be difficult and time-consuming to find using hand-designed experiments.


Assuntos
Agricultura/métodos , Cibernética/métodos , Ambiente Controlado , Ocimum basilicum/metabolismo , Folhas de Planta/metabolismo , Aprendizado de Máquina , Metabolômica , Projetos Piloto , Projetos de Pesquisa , Compostos Orgânicos Voláteis/metabolismo
3.
Biotechnol Prog ; 34(4): 858-867, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29708637

RESUMO

Diauxic growth of Escherichia coli is driven by a host of internal, complex regulatory actions. In this classic scenario of cellular control, the cell employs a rational algorithm to modulate its metabolism in a competitive fashion. Cybernetic models of metabolism, whose development now spans three decades, were first formulated to describe regulation of cells in complex, multi-substrate environments. They modeled this scenario using the hypothesis that the formation of the enzymatic machinery is regulated to maximize a return on investment. While this assumption is made on the basis of logical arguments rooted in evolutionary principles, little effort has been taken to validate if enzymes are truly synthesized in the same fashion that is predicted by cybernetic variables. This work revisits the original cybernetic models describing diauxic growth and compares their predictions of enzyme synthesis control with time series gene expression data in microarray and qRT-PCR formats. Three separate studies are made for two different strains of E. coli. The first is for the growth of E. coli BW25113 on a mixture of glucose and acetate, whose gene expression changes are metered by microarray. Another is also for the sequential consumption of glucose and acetate but involves strain MG1655 and employs qRT-PCR. The final is for E. coli MG1655 on glucose and lactose. By demonstrating how cybernetic variables for induced enzyme synthesis mimic the behavior of transcriptional data, a strong argument for using cybernetic models is made. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:858-867, 2018.


Assuntos
Cibernética/métodos , Escherichia coli/metabolismo , Algoritmos , Simulação por Computador , Escherichia coli/genética , Glucose/metabolismo , Lactose/metabolismo , Modelos Biológicos , Transcriptoma/genética
4.
Biosystems ; 148: 22-31, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27496574

RESUMO

The aim of this paper is to propose that current robotic technologies cannot have intentional states any more than is feasible within the sensorimotor variant of embodied cognition. It argues that anticipation is an emerging concept that can provide a bridge between both the deepest philosophical theories about the nature of life and cognition and the empirical biological and cognitive sciences steeped in reductionist and Newtonian conceptions of causality. The paper advocates that in order to move forward, cognitive robotics needs to embrace new platforms and a conceptual framework that will enable it to pursue, in a meaningful way, questions about autonomy and purposeful behaviour. We suggest that hybrid systems, part robotic and part cultures of neurones, offer experimental platforms where different dimensions of enactivism (sensorimotor, constitutive foundations of biological autonomy, including anticipation), and their relative contributions to cognition, can be investigated in an integrated way. A careful progression, mindful to the deep philosophical concerns but also respecting empirical evidence, will ultimately lead towards unifying theoretical and empirical biological sciences and may offer advancement where reductionist sciences have been so far faltering.


Assuntos
Cognição/fisiologia , Biologia Computacional/métodos , Robótica/métodos , Biologia Sintética/métodos , Animais , Interfaces Cérebro-Computador , Biologia Computacional/tendências , Cibernética/métodos , Humanos , Psicofisiologia/métodos , Robótica/tendências , Biologia Sintética/tendências
5.
IEEE Trans Cybern ; 46(12): 3388-3400, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26731783

RESUMO

Human-robot cooperation in complex environments must be fast, accurate, and resilient. This requires efficient communication channels where robots need to assimilate information using a plethora of verbal and nonverbal modalities such as hand gestures, speech, and gaze. However, even though hybrid human-robot communication frameworks and multimodal communication have been studied, a systematic methodology for designing multimodal interfaces does not exist. This paper addresses the gap by proposing a novel methodology to generate multimodal lexicons which maximizes multiple performance metrics over a wide range of communication modalities (i.e., lexicons). The metrics are obtained through a mixture of simulation and real-world experiments. The methodology is tested in a surgical setting where a robot cooperates with a surgeon to complete a mock abdominal incision and closure task by delivering surgical instruments. Experimental results show that predicted optimal lexicons significantly outperform predicted suboptimal lexicons (p <; 0.05) in all metrics validating the predictability of the methodology. The methodology is validated in two scenarios (with and without modeling the risk of a human-robot collision) and the differences in the lexicons are analyzed.


Assuntos
Cibernética/métodos , Cibernética/normas , Robótica/métodos , Interface Usuário-Computador , Algoritmos , Simulação por Computador , Fixação Ocular , Cirurgia Geral/educação , Gestos , Humanos , Análise e Desempenho de Tarefas
6.
IEEE Trans Cybern ; 46(12): 2911-2923, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26552105

RESUMO

The objective of a socially assistive robot is to create a close and effective interaction with a human user for the purpose of giving assistance. In particular, the social interaction, guidance, and support that a socially assistive robot can provide a person can be very beneficial to patient-centered care. However, there are a number of research issues that need to be addressed in order to design such robots. This paper focuses on developing effective emotion-based assistive behavior for a socially assistive robot intended for natural human-robot interaction (HRI) scenarios with explicit social and assistive task functionalities. In particular, in this paper, a unique emotional behavior module is presented and implemented in a learning-based control architecture for assistive HRI. The module is utilized to determine the appropriate emotions of the robot to display, as motivated by the well-being of the person, during assistive task-driven interactions in order to elicit suitable actions from users to accomplish a given person-centered assistive task. A novel online updating technique is used in order to allow the emotional model to adapt to new people and scenarios. Experiments presented show the effectiveness of utilizing robotic emotional assistive behavior during HRI scenarios.


Assuntos
Cibernética , Emoções/fisiologia , Relações Interpessoais , Modelos Psicológicos , Robótica , Tecnologia Assistiva , Cibernética/instrumentação , Cibernética/métodos , Humanos , Robótica/instrumentação , Robótica/métodos
7.
IEEE Trans Cybern ; 46(11): 2609-2621, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26540722

RESUMO

Real-life tracking tasks often show preview information to the human controller about the future track to follow. The effect of preview on manual control behavior is still relatively unknown. This paper proposes a generic operator model for preview tracking, empirically derived from experimental measurements. Conditions included pursuit tracking, i.e., without preview information, and tracking with 1 s of preview. Controlled element dynamics varied between gain, single integrator, and double integrator. The model is derived in the frequency domain, after application of a black-box system identification method based on Fourier coefficients. Parameter estimates are obtained to assess the validity of the model in both the time domain and frequency domain. Measured behavior in all evaluated conditions can be captured with the commonly used quasi-linear operator model for compensatory tracking, extended with two viewpoints of the previewed target. The derived model provides new insights into how human operators use preview information in tracking tasks.


Assuntos
Cibernética/métodos , Sistemas Homem-Máquina , Modelos Teóricos , Humanos
8.
IEEE Trans Cybern ; 46(2): 568-79, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26080390

RESUMO

This paper presents salient features of human-human interaction where one person with limited auditory and visual perception of the environment (a follower) is guided by an agent with full perceptual capabilities (a guider) via a hard rein along a given path. We investigate several salient features of the interaction between the guider and follower such as: 1) the order of an autoregressive (AR) control policy that maps states of the follower to actions of the guider; 2) how the guider may modulate the pulling force in response to the trust level of the follower; and 3) how learning may successively apportion the responsibility of control across different muscles of the guider. Based on experimental systems identification on human demonstrations from ten pairs of naive subjects, we show that guiders tend to adopt a third-order AR predictive control policy and followers tend to adopt second-order reactive control policy. Moreover, the extracted guider's control policy was implemented and validated by human-robot interaction experiments. By modeling the follower's dynamics with a time varying virtual damped inertial system, we found that it is the coefficient of virtual damping which is most sensitive to the trust level of the follower. We used these experimental insights to derive a novel controller that integrates an optimal order control policy with a push/pull force modulator in response to the trust level of the follower monitored using a time varying virtual damped inertial model.


Assuntos
Cibernética/instrumentação , Robótica/instrumentação , Tato/fisiologia , Pessoas com Deficiência Visual/reabilitação , Adulto , Cibernética/métodos , Desenho de Equipamento , Humanos , Adulto Jovem
9.
IEEE Trans Cybern ; 46(3): 655-67, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25823055

RESUMO

An intelligent human-robot interaction (HRI) system with adjustable robot behavior is presented. The proposed HRI system assists the human operator to perform a given task with minimum workload demands and optimizes the overall human-robot system performance. Motivated by human factor studies, the presented control structure consists of two control loops. First, a robot-specific neuro-adaptive controller is designed in the inner loop to make the unknown nonlinear robot behave like a prescribed robot impedance model as perceived by a human operator. In contrast to existing neural network and adaptive impedance-based control methods, no information of the task performance or the prescribed robot impedance model parameters is required in the inner loop. Then, a task-specific outer-loop controller is designed to find the optimal parameters of the prescribed robot impedance model to adjust the robot's dynamics to the operator skills and minimize the tracking error. The outer loop includes the human operator, the robot, and the task performance details. The problem of finding the optimal parameters of the prescribed robot impedance model is transformed into a linear quadratic regulator (LQR) problem which minimizes the human effort and optimizes the closed-loop behavior of the HRI system for a given task. To obviate the requirement of the knowledge of the human model, integral reinforcement learning is used to solve the given LQR problem. Simulation results on an x - y table and a robot arm, and experimental implementation results on a PR2 robot confirm the suitability of the proposed method.


Assuntos
Inteligência Artificial , Cibernética/métodos , Robótica/métodos , Simulação por Computador , Humanos , Modelos Neurológicos , Análise e Desempenho de Tarefas
10.
Sud Med Ekspert ; 58(3): 40-43, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26245103

RESUMO

The objective of the present publication was to discuss the possibility of application of cybernetic modeling methods to overcome the apparent discrepancy between two kinds of the speech records, viz. initial ones (e.g. obtained in the course of special investigation activities) and the voice prints obtained from the persons subjected to the criminalistic examination. The paper is based on the literature sources and the materials of original criminalistics expertises performed by the authors.


Assuntos
Cibernética/métodos , Medicina Legal/métodos , Fonética , Acústica da Fala , Medida da Produção da Fala , Qualidade da Voz/fisiologia , Prova Pericial/métodos , Humanos , Medida da Produção da Fala/instrumentação , Medida da Produção da Fala/métodos
11.
IEEE Trans Cybern ; 45(12): 2780-91, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25706979

RESUMO

In this paper, identification methods are proposed to estimate the neuromuscular and visual responses of a multiloop pilot model. A conventional and widely used technique for simultaneous identification of the neuromuscular and visual systems makes use of cross-spectral density estimates. This paper shows that this technique requires a specific noninterference hypothesis, often implicitly assumed, that may be difficult to meet during actual experimental designs. A mathematical justification of the necessity of the noninterference hypothesis is given. Furthermore, two methods are proposed that do not have the same limitations. The first method is based on autoregressive models with exogenous inputs, whereas the second one combines cross-spectral estimators with interpolation in the frequency domain. The two identification methods are validated by offline simulations and contrasted to the classic method. The results reveal that the classic method fails when the noninterference hypothesis is not fulfilled; on the contrary, the two proposed techniques give reliable estimates. Finally, the three identification methods are applied to experimental data from a closed-loop control task with pilots. The two proposed techniques give comparable estimates, different from those obtained by the classic method. The differences match those found with the simulations. Thus, the two identification methods provide a good alternative to the classic method and make it possible to simultaneously estimate human's neuromuscular and visual responses in cases where the classic method fails.


Assuntos
Aeronaves , Cibernética/métodos , Retroalimentação Sensorial/fisiologia , Processamento de Sinais Assistido por Computador , Análise e Desempenho de Tarefas , Simulação por Computador , Humanos , Tato/fisiologia
12.
IEEE Trans Cybern ; 45(9): 1769-83, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25312975

RESUMO

During the last few decades, as a part of effort to enhance natural human robot interaction (HRI), considerable research has been carried out to develop human-like gaze control. However, most studies did not consider hardware implementation, real-time processing, and the real environment, factors that should be taken into account to achieve natural HRI. This paper proposes a fuzzy integral-based gaze control algorithm, operating in real-time and the real environment, for a robotic head. We formulate the gaze control as a multicriteria decision making problem and devise seven human gaze-inspired criteria. Partial evaluations of all candidate gaze directions are carried out with respect to the seven criteria defined from perceived visual, auditory, and internal inputs, and fuzzy measures are assigned to a power set of the criteria to reflect the user defined preference. A fuzzy integral of the partial evaluations with respect to the fuzzy measures is employed to make global evaluations of all candidate gaze directions. The global evaluation values are adjusted by applying inhibition of return and are compared with the global evaluation values of the previous gaze directions to decide the final gaze direction. The effectiveness of the proposed algorithm is demonstrated with a robotic head, developed in the Robot Intelligence Technology Laboratory at Korea Advanced Institute of Science and Technology, through three interaction scenarios and three comparison scenarios with another algorithm.


Assuntos
Cibernética/métodos , Fixação Ocular/fisiologia , Lógica Fuzzy , Cabeça/fisiologia , Modelos Biológicos , Robótica/métodos , Algoritmos , Humanos
13.
Artigo em Inglês | MEDLINE | ID: mdl-26737868

RESUMO

We describe the process towards the design of a safe, reliable, and intuitive emergency treatment unit to facilitate a higher degree of safety and situational awareness for medical staff, leading to an increased level of patient care during an epidemic outbreak in an unprepared, underdeveloped, or disaster stricken area. We start with a human-centered design process to understand the design challenge of working with Ebola treatment units in Western Africa in the latest Ebola outbreak, and show preliminary work towards cyber-physical technologies applicable to potentially helping during the next outbreak.


Assuntos
Cibernética/métodos , Doença pelo Vírus Ebola/terapia , África Ocidental , Algoritmos , Descontaminação , Surtos de Doenças/prevenção & controle , Humanos , Robótica
14.
IEEE Trans Cybern ; 44(10): 1726-37, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25222717

RESUMO

In real life, we often need to find multiple optimally sustainable solutions of an optimization problem. Evolutionary multimodal optimization algorithms can be very helpful in such cases. They detect and maintain multiple optimal solutions during the run by incorporating specialized niching operations in their actual framework. Differential evolution (DE) is a powerful evolutionary algorithm (EA) well-known for its ability and efficiency as a single peak global optimizer for continuous spaces. This article suggests a niching scheme integrated with DE for achieving a stable and efficient niching behavior by combining the newly proposed parent-centric mutation operator with synchronous crowding replacement rule. The proposed approach is designed by considering the difficulties associated with the problem dependent niching parameters (like niche radius) and does not make use of such control parameter. The mutation operator helps to maintain the population diversity at an optimum level by using well-defined local neighborhoods. Based on a comparative study involving 13 well-known state-of-the-art niching EAs tested on an extensive collection of benchmarks, we observe a consistent statistical superiority enjoyed by our proposed niching algorithm.


Assuntos
Algoritmos , Evolução Biológica , Cibernética/métodos , Modelos Biológicos
15.
IEEE Trans Cybern ; 44(10): 1884-97, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25222729

RESUMO

This paper presents a novel search metaheuristic inspired from the physical interpretation of the optic flow of information in honeybees about the spatial surroundings that help them orient themselves and navigate through search space while foraging. The interpreted behavior combined with the minimal foraging is simulated by the artificial bee colony algorithm to develop a robust search technique that exhibits elevated performance in multidimensional objective space. Through detailed experimental study and rigorous analysis, we highlight the statistical superiority enjoyed by our algorithm over a wide variety of functions as compared to some highly competitive state-of-the-art methods.


Assuntos
Algoritmos , Abelhas/fisiologia , Comportamento Animal/fisiologia , Cibernética/métodos , Modelos Biológicos , Fluxo Óptico/fisiologia , Animais
16.
Comput Intell Neurosci ; 2014: 373957, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25143763

RESUMO

Movement primitives or synergies have been extracted from human hand movements using several matrix factorization, dimensionality reduction, and classification methods. Principal component analysis (PCA) is widely used to obtain the first few significant eigenvectors of covariance that explain most of the variance of the data. Linear discriminant analysis (LDA) is also used as a supervised learning method to classify the hand postures corresponding to the objects grasped. Synergies obtained using PCA are principal component vectors aligned with dominant variances. On the other hand, synergies obtained using LDA are linear discriminant vectors that separate the groups of variances. In this paper, time varying kinematic synergies in the human hand grasping movements were extracted using these two diametrically opposite methods and were evaluated in reconstructing natural and American sign language (ASL) postural movements. We used an unsupervised LDA (ULDA) to extract linear discriminants. The results suggest that PCA outperformed LDA. The uniqueness, advantages, and disadvantages of each of these methods in representing high-dimensional hand movements in reduced dimensions were discussed.


Assuntos
Análise Discriminante , Força da Mão , Movimento/fisiologia , Análise de Componente Principal , Fenômenos Biomecânicos , Cibernética/instrumentação , Cibernética/métodos , Humanos , Dinâmica não Linear , Postura
17.
Artigo em Inglês | MEDLINE | ID: mdl-24580266

RESUMO

In biomechanics and biorobotics, muscles are often associated with reduced movement control effort and simplified control compared to technical actuators. This is based on evidence that the nonlinear muscle properties positively influence movement control. It is, however, open how to quantify the simplicity aspect of control effort and compare it between systems. Physical measures, such as energy consumption, stability, or jerk, have already been applied to compare biological and technical systems. Here a physical measure of control effort based on information entropy is presented. The idea is that control is simpler if a specific movement is generated with less processed sensor information, depending on the control scheme and the physical properties of the systems being compared. By calculating the Shannon information entropy of all sensor signals required for control, an information cost function can be formulated allowing the comparison of models of biological and technical control systems. Exemplarily applied to (bio-)mechanical models of hopping, the method reveals that the required information for generating hopping with a muscle driven by a simple reflex control scheme is only I=32 bits versus I=660 bits with a DC motor and a proportional differential controller. This approach to quantifying control effort captures the simplicity of a control scheme and can be used to compare completely different actuators and control approaches.


Assuntos
Retroalimentação Fisiológica/fisiologia , Modelos Biológicos , Modelos Estatísticos , Movimento/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Esforço Físico/fisiologia , Animais , Simulação por Computador , Cibernética/métodos , Entropia , Humanos , Armazenamento e Recuperação da Informação/métodos , Robótica/métodos
18.
Bioengineered ; 5(2): 73-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24145961

RESUMO

A general theory of biological systems, based on few fundamental propositions, allows a generalization of both Wierner and Berthalanffy approaches to theoretical biology. Here, a biological system is defined as a set of self-organized, differentiated elements that interact pair-wise through various networks and media, isolated from other sets by boundaries. Their relation to other systems can be described as a closed loop in a steady-state, which leads to a hierarchical structure and functioning of the biological system. Our thermodynamical approach of hierarchical character can be applied to biological systems of varying sizes through some general principles, based on the exchange of energy information and/or mass from and within the systems.


Assuntos
Algoritmos , Bioengenharia/métodos , Cibernética/métodos , Ecossistema , Modelos Biológicos , Biologia de Sistemas/métodos , Simulação por Computador , Retroalimentação Fisiológica , Humanos , Análise Numérica Assistida por Computador , Termodinâmica
19.
Sensors (Basel) ; 13(9): 12406-30, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-24048336

RESUMO

The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher's explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth) -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR) system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics.


Assuntos
Inteligência Artificial , Instrução por Computador/métodos , Gestos , Relações Interpessoais , Sistemas Homem-Máquina , Robótica/métodos , Interface para o Reconhecimento da Fala , Comunicação , Cibernética/métodos , Reconhecimento Automatizado de Padrão/métodos , Integração de Sistemas
20.
Int J Med Robot ; 9(2): 213-22, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23483681

RESUMO

BACKGROUND: The development of new diagnostic technologies for cerebrovascular diseases requires an understanding of the mechanism behind the growth and rupture of cerebral aneurysms. To provide a comprehensive diagnosis and prognosis of this disease, it is desirable to evaluate wall shear stress, pressure, deformation and strain in the aneurysm region, based on information provided by medical imaging technologies. METHODS: In this research, we propose a new cyber-physical system composed of in vitro dynamic strain experimental measurements and computational fluid dynamics (CFD) simulation for the diagnosis of cerebral aneurysms. A CFD simulation and a scaled-up membranous silicone model of a cerebral aneurysm were completed, based on patient-specific data recorded in August 2008. In vitro blood flow simulation was realized with the use of a specialized pump. A vision system was also developed to measure the strain at different regions on the model by way of pulsating blood flow circulating inside the model. RESULTS: Experimental results show that distance and area strain maxima were larger near the aneurysm neck (0.042 and 0.052), followed by the aneurysm dome (0.023 and 0.04) and finally the main blood vessel section (0.01 and 0.014). These results were complemented by a CFD simulation for the addition of wall shear stress, oscillatory shear index and aneurysm formation index. Diagnosis results using imaging obtained in August 2008 are consistent with the monitored aneurysm growth in 2011. CONCLUSION: The presented study demonstrates a new experimental platform for measuring dynamic strain within cerebral aneurysms. This platform is also complemented by a CFD simulation for advanced diagnosis and prediction of the growth tendency of an aneurysm in endovascular surgery.


Assuntos
Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular , Aneurisma Intracraniano/fisiopatologia , Modelos Cardiovasculares , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Cibernética/métodos , Módulo de Elasticidade , Dureza , Humanos , Resistência ao Cisalhamento , Resistência à Tração , Resistência Vascular
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