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In this paper we discuss the adequate filter parameter selection to obtain a low loss coaxial cable, out of which a narrowband filtering device is designed. The design parameters under interest are the attenuation constant (a) obtained, which will depend on the size of the rectangular coaxial cross section used. And the decision beyond which frequency higher order modes should start to propagate through...
Subgraph isomorphism (SI) detection is an important problem for several computer science subfields. In this paper we present a study of the subgraph isomorphism problem (SIP) and its relation with the Hamiltonian cycles and SAT problems. In particular, we describe how instances of those problems can be solved throughout SI detection (using problems reductions). In our experiments we use an algorithm...
Two most commonly IIR filters used in audio equalization are shelving filters and peaking filters. Traditional design of shelving and peaking filters is based on the design of analog filters, mainly Butterworth filters, and bilinear transformation. In this way, it is well known the design of first order shelving filters and second order peaking filters. Additionally, the resulting filter can be efficiently...
A detailed cellular existing coverage analysis was performed for the Informatics and Electronics Centre Building (CIE) at ITESM Campus Queretaro, using novel propagation modelling tools such as Measurement-based prediction (MbP) to predict signal strength levels across the five-storey building. An extensive set of radio measurements was performed in the 1900 MHz band to construct received signal strength...
To compute the filter coefficients of a digital filter, it is often necessary the solution of a set of linear equations using numerical methods. Unfortunately, if the number of unknowns is high, then the solution is likely to be error prone. To avoid this problem, this paper presents the use of the symbolic tool MAPLE to compute the filter coefficients. Consequently, the proposed solution is given...
In this work the development and construction of a digital audio effects gestural controller using IR sensors is presented. The design of this system is based on an optical IR Theremin capable of controlling an user-specified parameter using the proximity of the performer's hand or foot,
This data acquisition device can be used to acquire analogical and digital signals such as control variables (pressure, temperature, flow, level, etc.), biological signals, etc. In this case, we will apply it to control a tanks level. The tanks store different kinds of fluids; many times they are filled and controlled manually. The DAQ device has analogous inputs that can process data measurement...
DoS is an attack which overwhelm victims servers and services. Distributed DoS attacks do not let legitimate users to access services provided by servers. Several techniques have been proposed to mitigate such attacks. Preventive techniques have proven their effectiveness. However, most of those techniques require historic data and training. We propose a dynamic algorithm based on the concept of fuzzy...
This paper proposes a face recognition algorithm in which the discrete Gabor transform is used to extract the image face features vector that is then feed into a multilayer perceptron to be carried out the recognition task. The features vector, estimated using the Gabor transform, presents a small intra-person variation while the inter-persons variation is considerably large. This fact provides robustness...
Some document clustering tools automatically or semi-automatically produce document hierarchies. Commonly, they are stored as text or graphical files. As a result, applications are not able to use them before some kind of processing. A more recent representation of document hierarchies employs Extensible Markup Language. However, the reusability of this representation is diminished because the semantic...
The system described in this paper is able to monitor three vital signs of a patient: Oxygen Saturation Percentage, heart rate and temperature. It is accomplished using a SpO2 Sensor model DS-100A manufactured by Nellcor. Analyzing the signal obtained by this sensor is possible to measure SpO2 and heart rate. Temperature is measured using a LM-92 sensor manufactured by National Instruments. The user...
Several different fabrication techniques and materials have been proposed for the realization of low loss high-Q micromachined filters or tunable filters. In this paper a review of several filters that have been proposed over the last years is presented, including a discussion of topologies and the structures used to make microwave filters
Miller's theorem has proven its usefulness in analyzing feedback amplifiers. However, it does not provide accurate results for either gain, input and output impedances. This paper presents an alternative analysis of a feedback amplifier by using the extra element theorem (EET) and the unified feedback model (UFM). The results obtained are accurate when compared to direct analysis. The paper presents...
Membrane systems are computational models inspired in basic characteristics of biological membranes concerning the way they process chemical compounds, energy and information. They represent a new distributed parallel computation model where the cooperation between objects (membranes) is possible to solve complex problems. Membrane systems exhibit a hierarchical topology where well-delimited computer...
Currently are different commercial PCI cards that included instruments like scopes, function generator, pattern generator, and data acquisition card with digital ports. The main objective of this paper is design and built a measurement instrument basically an oscilloscope; our interest is development the hardware, firmware and the software
In this paper the design and construction of a mobile robot for path planning is described. This robot is able to reach a specific point by processing the information of an image taken by an eye in the sky-like camera. The path is generated by a computer program that determines the shortest path considering the obstacle-free space from the start point to the goal. This information is encoded into...
The exchange of information on the Web has recently gained momentum with the raise of some socially-oriented collaborative trends. Current phenomena such as blogging, wikis or social software sites such as Digg or Slashdot have emerged as a paradigm shift in which the consumer-producer equation on the Web has reverted. The increasing success of these initiatives in pointing at and recommending resources...
The use of 3D surface sensor has been recently proposed for patient positioning in radiotherapy treatments. In this kind of applications, relating the coordinate system of 3d sensor with the coordinate system of treatment's room is crucial and needs a sensor's calibration. Sensor's calibration depends of its measuring principle; so calibrating a time-of-fly sensor has some differences to calibrating...
When intelligent agents get new knowledge and this knowledge must be added or updated to their knowledge base, then it is important to avoid inconsistencies. In this paper, we propose a semantics for updates consisting of a sequence of programs. The semantics is proposed as an application of an extension of the notion of generalized answer sets. This extension is also introduced in this work
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