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In this paper we evaluate the performance of the new algorithm of the TCP protocol for a long distance wireless link in the Galapagos Islands. In order to achieve this goal, it has been started from a study of different standards and tools for this project, besides of the amendments to the TCP protocol for wireless environments. Finally, the network was implemented and preceded to inject traffic to...
This paper presents the analysis, design and implementation of a Learning Object Repository for Mobile Devices, it is remarkable the use of free software tools is presented. The use of mobile devices has taken a great preponderance in business, personal life and education. One example is the increasing educational applications designed to support learning in different educational use. The use of mobile...
In this paper we present the state of the art in the development of smart sensors based on MEMS (Micro-Electro-Mechanical Systems), where we will explain its evolution from the beginning until the latest generation of smart sensors, deepening in architecture and operational philosophy. It also presents an analysis of the future prospects of the new designs that could satisfy the demands of the current...
How to control and monitor devices when I'm not at home? It is a question that until the last century did not have an overwhelming answer from the engineering field. The technological development of recent years has allowed us to perform this task by using software and hardware tools: monitoring different devices from our smartphone comes down to simply downloading an app or entering a website. This...
The synthesis and analysis of a state space model of a drive system for the extraction of a pipeline inspection robot is described in this paper. This system has been developed to address the need for inspection of the pipe network distributing jet fuel to the fleet in a national airport. Since it is important to preserve the health of the pipes, the extraction of the inspection robot must be carefully...
Rotating systems components such as rotors, have dynamic characteristics which are of great importance to understand because they may cause failure of turbomachinery. Therefore, it is required to study a dynamic model to predict some vibration characteristics, in this case, the natural frequencies and mode shapes (both of free vibration) of a turbocompressor shaft by using the finite element analysis...
We present the design and implementation of a system access control using radio frequency identification (RFID) controlled by Arduino platform. The proposed system consists of a radio frequency reader (RC522), a set passive tags (identification cards), microcontroller Arduino MEGA, and graphical user interface (GUI) implemented in Matlab®. Through a GUI, it is possible to take control of access to...
This paper describes a procedure to get a vibrational model of a combustion chamber from a gas turbine, with the purpose to set the basis of a future acoustic phenomenon analysis. The combustion chamber model is grounded in a sub-damped modal model in which its freedom degrees are according with its flexible modal modes and their corresponded natural frequencies which were gotten from impact tests...
In this article, we discuss the current situation of free software awareness and use in middle education. The established target population is educational institutions in Xalapa, Veracruz, Mexico. The sample is formed by students and teachers from said level and the interest from students on training, usage and distribution of free software is emphasized.
In this study described the use of the previously Finite Difference Time Domain method, for analyze the behavior electromagnetic with a diffractor or Perfect Electric Conductor inside of an antennas circular array of 17 elements, this array consists of one transmission antenna and 16 receiving antennas RX. The system uses a Gaussian pulse as excitation with a frequency of 7.5 GHz. The method solves...
Ultra low-power electronic design is the backbone methodology tool in sensor integration architectures, sensor networking, biomedical applications and wearable electronics. These implementations demand multiple supply voltage domains with different current level requirements that vary from a few microamperes to hundred of miliamperes, such task is done by voltage regulators. This work studies the...
We have studied the electrical conduction in active layers of organic photodetectors based copper phthalocyanines and PEDOT: PSS, with ITO substrate and added by casting, the result was an organic semiconductor device was tested in a voltage range of −0.5 to 1.2 volts, with a wavelength of absorption in the active layer of 750nm, further we used a computational chemistry package Gaussian 09 to get...
This paper studies the potential impact of using space-time information in the mitigation of the Non-Line-Of-Sight condition in mobile subscriber's positioning systems. First of all, this work discusses the positioning problem based on measures of Time Differences Of Arrival departing from a more exact characterization of the signal statistics and including some geometrical restrictions to achieve...
The development of antennas for RFID tags requires measurement of the parameters; as well as, the response of these to be questioned by a reader, the variation of the parameters with simulation tools and building prototypes of antennas can be evaluated, compared, and verified to determine whether the label complies with the basic requirements. To do this, it requires a methodology to help determine...
Time series and imaging using fractal analysis have been implemented in many areas of science and engineering, economics, biology and statistics among others, for their ability to detect auto-similarities or irregular behavior patterns. Such advantage has represented a significant advance in the monitoring and control of variables processes and research. But all this has been done in most cases with...
For the current manuscript, an automatic gain control circuit is proposed; it is designed in current-mode. Additionally, it has a digitally controlled feedback. The design follows a bottom-up designing philosophy; then, the first step is to simulate the mathematical behavior of the proposal. Matlab is the mathematical tool used for mathematical validation. After corroborating its behavior, the circuit...
The current work proposes an algorithm for implementing a 32-bits chaotic map; which is implemented in an 8-bits microcontroller. For the algorithm, many operations are modified. The operations consist on multiplication, accommodation, addition, and shifting; the modifications are needed because the embedded operations were originally designed for 8-bit numbers. Once the microcontroller algorithm...
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