Search results for " sensor"
showing 10 items of 1714 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…
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…
UAV-Aided Secure Short-Packet Data Collection and Transmission
2023
Benefiting from the deployment flexibility and the line-of-sight (LoS) channel conditions, unmanned aerial vehicle (UAV) has gained tremendous attention in data collection for wireless sensor networks. However, the high-quality air-ground channels also pose significant threats to the security of UAV aided wireless networks. In this paper, we propose a short-packet secure UAV-aided data collection and transmission scheme to guarantee the freshness and security of the transmission from the sensors to the remote ground base station (BS). First, during the data collection phase, the trajectory, the flight duration, and the user scheduling are jointly optimized with the objective of maximizing t…
Two-step cross correlation-based algorithm for motion estimation applied to fertilizer granules' motion during centrifugal spreading
2011
Imaging systems are progressing in both accuracy and ro- bustness, and their use in precision agriculture is increasing accordingly. One application of imaging systems is to understand and control the cen- trifugal fertilizing spreading process. Predicting the spreading pattern on the ground relies on an estimation of the trajectories and velocities of ejected granules. The algorithms proposed to date have shown low ac- curacy, with an error rate of a few pixels. But a more accurate estimation of the motion of the granules can be achieved. Our new two-step cross- correlation-based algorithm is based on the technique used in particle image velocimetry (PIV), which has yielded highly accurate…
Having a choice: does it influence pleasantness and food intake?
2014
Having a choice: does it influence pleasantness and food intake?. 6. European conference on sensory and consumer research: a sense of life
Goût et préférences du consommateur âgé
2017
Revue; Goût et préférences du consommateur âgé. Sixième journée mondiale de la déglutition :
Tailoring the excitation of fundamental flexural guide waves in coated bone by phase-delayed array: Two-dimensional simulations
2015
The fundamental flexural guided wave (FFGW) enables ultrasonic assessment of cortical bone thickness. In vivo, it is challenging to detect this mode, as its power ratio with respect to disturbing ultrasound is reduced by soft tissue covering the bone. A phase-delayed ultrasound source is proposed to tailor the FFGW excitation in order to improve its power ratio. This situation is analyzed by 2D finite-element simulations. The soft tissue coating (7-mm thick) was simulated as a fluid covering an elastic plate (bone, 2–6 mm thick). A six-element array of emitters on top of the coating was excited by 50-kHz tone bursts so that each emitter was appropriately delayed from the previous one. Respo…
Microwave gas sensor based on graphene aerogel for breath analysis
2022
Exhaled breath can be used for early detection and diagnosis of diseases, monitoring metabolic activity, and precision medicine. In this work, we design and simulate a microwave sensor in which thin graphene aerogels are integrated into rectangular microwave waveguides. Graphene aerogels are ideal sensing platforms for gases and volatile compounds as they combine extremely high surface-to-volume ratio and good electrical conductivity at RF and microwave frequencies. The latter is modified by exposure to different gases, and -when integrated into a waveguide- these changes result in significant shifts in transmission and reflection scattering parameters. We model the aerogel as a graphene gr…
Touch, gender, and sexuality in Zola's La Curée
2022
This paper addresses the issues of gender and sexuality in Zola's La Curée from a sensory studies perspective, focusing specifically on touch. The novel's atmosphere of softness is rooted in the Second Empire's obsession for luxurious comfort as well as "mollitia", an ethical and aesthethical concept inherited from Latin culture.