Diseño de un sistema de monitoreo del comportamiento de vacas en tiempo real basado en redes de sensores inalámbricos y algoritmo de clustering de K-Means

Introduction: The present article is the product of the research whose code CS20.04, carried out during 2020. This work was supported by the Institute of Information Technology (IOIT), Vietnam Academy of Science and Technology (VAST). Problem: Animal monitoring is a significant problem in the agricultural sector. The primary purpose is to monitor the health of animals regularly. Consequently, animal welfare and product quality could be improved, leading to an improvement in profit. Cow behavior recognition system was considered as the right solution for cow monitoring. The requirements for this kind of system are economical, high performance, and real-time. Objective: The research objective is to design a real-time cow monitoring system based on wireless sensor networks and the K-means clustering algorithm. Methodology: A wireless sensor node was designed to measure the collar-mounted acceleration data using an accelerometer. Firstly, the collected data were classified into three classes based on the VeDBA (Vector of Dynamic Body Acceleration) feature using the K-means algorithm. Then, the thresholds for VeDBA in the previous step were used to classify new data. Results: Three behaviors (including feeding, lying, and standing) were classified in real-time with the accuracy of classification about 89%.   Conclusion: The proposed system could be adapted in monitoring cow in real-time, the behavior classification could be implemented on the microcontroller. The results confirmed the reliability of the proposed system. Originality: The behavior classification could be implemented on the microcontroller for the first time in monitoring cow. Limitations: Only three behaviors were classified in the experiment

Monitoring of Landslides in Mountainous Regions based on FEM Modelling and Rain Gauge Measurements

Vietnam is a country heavily influenced by climate change. The effect of climate change leads to a series of dangerous phenomena, such as landslides. Landslides occur not only in the mountainous province, but also in Delta provinces, where hundreds of landslides are reported annually in the North-Western provinces of Vietnam. These events have catastrophic impact to the community as well as the economy. In mountainous areas, the conditions for landslides to occur are met frequently, especially after heavy rains or geological activity, causing harm to the community as well as damaging or destroying much needed infrastructure and key transport routes. However, in Vietnam, investment in mountainous regions has been often lower than in urban areas. The meteorology monitoring and forecasting systems are ill equipped and overloaded, so they cannot deliver earlier and more accurate forecasts for complex weather events, unable to provide timely warnings. It can be seen that in countries that landslide often occur, researchers have been trying to develop low cost and efficient landslide detection system. This paper precisely addressed the problems mentioned, by designing and implementing an efficient and reliable Landslide Monitoring and Early Warning (LMnE) system based on the 3G/2G mobile communication system, and a rain gauge at the field site along with a carefully FEM (finite element method) simulation using the rain density information on the server. The system uses advanced processing algorithms combining obtained data at the central station

Improvements on the performance of subcarrier multiplexing/wavelength division multiplexing based radio over fiber system

Radio over fiber (RoF) techniques are good candidates to create the backbone of the next generation of wireless networks. Many parameters affect RoF communications such as amplified spontaneous emission noise (ASE), four-wave mixing nonlinearity (FWM), the modulation, channel spacing, switching voltage, and phase shifter. In this paper, we propose an improved model of RoF communication systems using subcarrier multiplexing/wavelength division multiplexing (SCM/WDM) technique with unequal channel spacing and 1-km Erbium-doped fiber amplifier (EDFA). Simulation results confirmed that we could obtain the lowest bit error rate and noises when the EDFA is placed at 1 km from the transmitter by using optical single-sideband (OSSB) modulation at frequencies 193.1 THz, 193.2 THz, 193.35 THz, and 193.6 THz

La eficiencia de aplicar muestreo comprimido y resolución múltiple en tomografía por ultrasonido

Introduction: This publication is the product of  research developed within the research lines of the Smart Sensing, Signal Processing, and Applications (3SPA)  research  group  throughout  2018,  which  supports  the  work  of  a  doctor’s degree at VNU University of Engineering & Technology, Vietnam. Problem: The limitations of diagnostic ultrasound techniques using echo information has motivated the study of new imaging models in order to create additional quantitative ultrasound information in multi-model imaging devices. A promising solution is to use image sound contrast because it is capable of detecting changes in diseased tissue structures. Ultrasound tomography shows speed-of-sound changes in the propagation medium of sound waves. This technique is primarily used for imaging cancer-causing cells in womens’ breasts. The Distorted Born Iterative Method (DBIM), based on the first-order Born approximation, is an efficient diffraction tomography approach. The compressed sensing technique is utilized for DBIM to obtain the high-quality ultrasound image, although the image reconstruction process is quite long. Objective: The objective of the research is to propose an combined method for the efficient ultrasound tomography. Methodology: In this paper, we proposed an approach to enhance the imaging quality and to reduce the imaging time by applying the compressed sensing technique along with the multi-resolution technique for the DBIM. Results: The simulation results indicate that the imaging time is reduced by 33% and the imaging quality is improved by 83%. Conclusion: This project seeks to propose an improvement in ultrasound tomography. The simulated results confirmed the realibility of the propsed method. Originality: Through this research, a combined method of compressed sensing and multiple resolution are formulated for the first time in ultrasound tomography. Limitations: The lack of experiments to confirm the proposed method.Introducción: esta publicación es el producto de la investigación desarrollada dentro de las líneas del grupode investigación Detección Inteligente, Procesamiento de Señales y Aplicaciones (3SPA, Smart Sensing, Signal Processing, and Applications) a lo largo de 2018, que respalda el trabajo de un doctorado en la Universidad deIngeniería y Tecnología de VNU, Vietnam. Problema: las limitaciones de las técnicas de diagnóstico por ultrasonido que utilizan información de eco han motivado el estudio de nuevos modelos de imágenes para crear información cuantitativa adicional de ultrasonidos en dispositivos de imágenes de modelos múltiples. Una solución prometedora es utilizar el contraste de sonido de la imagen porque es capaz de detectar cambios en las estructuras de los tejidos enfermos. La tomografía por ultrasonido muestra los cambios en la velocidad del sonido en el medio de propagación de las ondas sonoras. Esta técnica se usa principalmente para obtener imágenes de células que causan cáncer en los senos de las mujeres.  Objetivo: el objetivo de la investigación es proponer un método combinado para la tomografía de ultrasonido eficiente. Metodología: en este documento se propuso un enfoque para mejorar la calidad de la imagen y reducir el tiempo diante la aplicación de la técnica de detección comprimida junto con la técnica de resolución múltiplepara el DBIM. Resultados: los resultados de la simulación indican que el tiempo de imagen se reduce en un 33 % y la calidad de imagen se mejora en un 83 %. Conclusión: este proyecto busca proponer una mejora en la tomografía por ultrasonido. Los resultados simulados confirmaron la viabilidad del método sugerido. Originalidad: a través de esta investigación, se formula por primera vez un método combinado de detección comprimida y resolución múltiple en la tomografía por ultrasonido. Limitaciones: la falta de experimentos para confirmar el método propuesto

A Uniqueness Theorem for Meromorphic Mappings with Two Families of Hyperplanes

International audienceIn this paper, we extend the uniqueness theorem for meromorphic mappings to the case where the family of hyperplanes depends on the meromorphic mapping and where the meromorphic mappings may be degenerate

An Extension of the Cartan Nochka- Second Main Theorem for Hypersurfaces

arXiv 0911.2562 (13/11/09)International audienceIn 1983, Nochka proved a conjecture of Cartan on defects of holomorphic curves in CP^n relative to a possibly degenerate set of hyperplanes. In this paper, we generalize the Nochka's theorem to the case of curves in a complex projective variety intersecting hypersurfaces in subgeneral position

Improvement of Tuning Fork Gyroscope Drive-mode Oscillation Matched using a Differential Driving Suspension Frame

This paper presents a novel design of a vibration tuning fork gyroscope (TFG) based on a differential driving suspension coupling spring between two gyroscopes. The proposed TFG is equivalent to a transistor differential amplifier circuit. The mechanical vibrations of driving frames are, therefore, well matched. The matching level depends on stiffness of spring. When three various TFG structures respond to differential stiffness of spring, their the driving frame mechanical vibration is well matched in case the input excitation driving differential phase is less than 3.5°, 2.5°, and 4°, respectively. The fabricated tuning fork gyroscope linearly operates in the range from -200 to +200 degree/s with the resolution of about 0.45 mV/degree/s

Power beacon-assisted energy harvesting in a half-duplex communication network under co-channel interference over a Rayleigh fading environment: Energy efficiency and outage probability analysis

In this time, energy efficiency (EE), measured in bits per Watt, has been considered as an important emerging metric in energy-constrained wireless communication networks because of their energy shortage. In this paper, we investigate power beacon assisted (PB) energy harvesting (EH) in half-duplex (HD) communication network under co-channel Interferer over Rayleigh fading environment. In this work, we investigate the model system with the time switching (TS) protocol. Firstly, the exact and asymptotic form expressions of the outage probability (OP) are analyzed and derived. Then the system EE is investigated and the influence of the primary system parameters on the system performance. Finally, we verify the correctness of the analytical expressions using Monte Carlo simulation. Finally, we can state that the simulation and analytical results are the same.Web of Science1213art. no. 257