Search results for "Sensor"
showing 10 items of 4594 documents
Maximum Lifetime Problem in Sensor Networks with Limited Channel Capacity
2016
We analyze the maximum lifetime problem in sensor networks with limited channel capacity for multipoint-to-multipoint and broadcast data transmission services. For the transmission model in which the transmitter adjust the power of its radio signal to the distance to the receiver we propose a new Signal to Interference plus Noise Ratio function and use it to modify the Shannon-Hartley channel capacity formula. We show, that in order to achieve an optimal data transmission regarding considered the maximum lifetime problem we cannot allow for any interference of signals. For considered transmission model and the modified capacity formula we solve the maximum lifetime problem in one dimensiona…
Efectos del entrenamiento sensorimotor previo a la cirugía de artroplastia total en sujetos con osteoartritis de rodilla
2020
Introducción: El entrenamiento de fuerza y el sensorimotor son dos intervenciones comúnmente empeladas en sujetos con osteoartritis (OA) de rodilla. Sin embargo, una revisión sistemática de la literatura implementada como parte de este trabajo de tesis doctoral, reveló que la evidencia - especialmente en lo referente al entrenamiento sensorimotor - cuando se aplican en el periodo preoperatorio a la artroplastia total de rodilla (ATR), fue inconcluyente y no permitió extraer conclusiones sólidas sobre su efectividad en el postoperatorio temprano y tras un año de seguimiento. Objetivos: Estudiar los efectos derivados de implementar una intervención experimental preoperatoria, que combine el e…
In Defense of Cities : On Negative Presentation of Urban Areas in Environmental Preference Studies
2019
This paper critiques a common research method, image-based studies, in assessing environmental preferences. The method is used, in particular, in the fields of environmental psychology, landscape studies, and health studies, here called empirical environmental preference studies or EEP studies. I argue that the established view in the EEP field that nature is inherently experienced as more aesthetically appealing and restorative than urban environments may be biased because of the image-based method. This paper presents a literature review of EEP studies, discussing them in a framework of environmental and everyday aesthetics. The conclusion is that EEP studies may strip cities of their phy…
Older Age Increases the Amplitude of Muscle Stretch-Induced Cortical Beta-Band Suppression But Does not Affect Rebound Strength
2020
Healthy aging is associated with deterioration of the sensorimotor system, which impairs balance and somatosensation. However, the exact age-related changes in the cortical processing of sensorimotor integration are unclear. This study investigated primary sensorimotor cortex (SM1) oscillations in the 15–30 Hz beta band at rest and following (involuntary) rapid stretches to the triceps surae muscles (i.e., proprioceptive stimulation) of young and older adults. A custom-built, magnetoencephalography (MEG)-compatible device was used to deliver rapid (190°·s−1) ankle rotations as subjects sat passively in a magnetically-shielded room while MEG recorded their cortical signals. Eleven young (age…
Older Age Increases the Amplitude of Muscle Stretch-Induced Cortical Beta-Band Suppression But Does not Affect Rebound Strength
2020
Healthy aging is associated with deterioration of the sensorimotor system, which impairs balance and somatosensation. However, the exact age-related changes in the cortical processing of sensorimotor integration are unclear. This study investigated primary sensorimotor cortex (SM1) oscillations in the 15–30 Hz beta band at rest and following (involuntary) rapid stretches to the triceps surae muscles (i.e., proprioceptive stimulation) of young and older adults. A custom-built, magnetoencephalography (MEG)-compatible device was used to deliver rapid (190°·s−1) ankle rotations as subjects sat passively in a magnetically-shielded room while MEG recorded their cortical signals. Eleven young (age…
Optimization of Delayed-State Kalman-Filter-based Algorithm via Differential Evolution for Sensorless Control of Induction Motors
2010
This paper proposes the employment of the differential evolution (DE) to offline optimize the covariance matrices of a new reduced delayed-state Kalman-filter (DSKF)-based algorithm which estimates the stator-flux linkage components, in the stationary reference frame, to realize sensorless control of induction motors (IMs). The DSKF-based algorithm uses the derivatives of the stator-flux components as mathematical model and the stator-voltage equations as observation model so that only a vector of four variables has to be offline optimized. Numerical results, carried out using a low-speed training test, show that the proposed DE-based approach is very promising and clearly outperforms a cla…
Aligned microcontact printing of biomolecules on microelectronic device surfaces
2001
Microcontact printing (/spl mu/CP) of extracellular matrix proteins is a fascinating approach to control cell positioning and outgrowth, which is essential in the development of applications ranging from cellular biosensors to tissue engineering. Microelectronic devices can be used to detect the activity from a large number of recording sites over the long term. However, signals from cells can only be recorded at small sensitive spots. Here, the authors present an innovative setup to perform aligned /spl mu/CP of extracellular matrix proteins on microelectronic devices in order to guide the growth of electrogenic cells specifically to these sensitive spots. The authors' system is based on t…
Developmental dyslexia: Visual abnormalities during ocular rotation
2005
[u]Purpose[/u]: Most of the studies dealing with visual perception disabilities in children suffering from developmental dyslexia have been done in orthophoric position. The objective of the present study is to explore the visual perception during eye movements. [u]Methods[/u]: Sixty male patients (11.8 ± 1.8 years) were examined by neuropsychologists to evaluate reading difficulties. Visual perception during ocular rotation was assessed with a Clement Clarke synoptophore with G3–G4 slides, in primary gaze, then laterally at 20, 30 and 40° in dim light. [u]Results[/u]: Three main abnormalities were found. • Isolated perception abnormalities with intermittent shading of the image, central, p…
Le traitement des expressions faciales au cours de la première année : développement et rôle de l'olfaction
2015
The first year of life is critical for the development of the abilities to process facial expressions. Olfaction and expressions are both strongly linked to each other, and it is well known that infants are able to multisensorially integrate their environment as early as birth. However, most of the studies interested in multisensory processing of facial expressions are restricted to the investigation of audio-visual interactions.In this thesis, we firstly aimed to resolve different issues concerning the ontogenesis of infants’ ability to process facial expressions. Our results allowed to specify the development of visual exploratory strategies of facial emotions along the first year of life…
In-mouth mechanism leading to the perception of fat in humans: from detection to preferences. The particular role of saliva
2013
In humans, the perception of fat in food is a complex process involving many sensory modalities (texture, aromaand flavour). Themouth is the first place in which the process of digestion begins. During this process, a bolus is formed in which saliva is significantly incorporated. For solids and semi-solid fatty matrices, saliva and the shear forces applied during mastication contribute to their breakdown and/or destabilisation in emulsified systems. These mechanisms are often dependent on the fat content of the food and thus play an important role in not only the perception of texture but also the release of compounds responsible for the flavour of “fat”. In addition, saliva is directly inv…