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Ensenada, Mexico

Fimbres-Castro C.,UABC | Alvarez-Borrego J.,CICESE | Bueno-Ibarra M.A.,IPN
Optical Engineering

We present a nonlinear correlation methodology to recognize objects. This system is invariant to position, rotation, and scale by using vectorial signatures obtained from the target such as those from problem images. Vectorial signatures are calculated through several mathematical transformations such as scale and Fourier transform. In this application, vectorial signatures are compared using nonlinear correlations. Also, experiments were carried out in order to find the noise tolerance. The discrimination coefficient was used as a metric in performance evaluation in presence of noise. In addition, spectral index and vectorial signature index are obtained in order to recognize objects in a simpler way. This technique has low computational cost. The invariance to position, rotation, and scale digital system was tested with 21 different fossil diatoms images. The results obtained are good, and the confidence level is above 95.4%. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). Source

Favela J.,CICESE | Tentori M.,UABC | Gonzalez V.M.,University of Manchester
International Journal of Human-Computer Interaction

The difficulties associated with the evaluation of ubiquitous computing (Ubicomp) technologies increase in application domains such as hospitals, where human life can be at risk, privacy of personal records is paramount, and labor is costly and highly distributed across space and time. For the last 6 years numerous Ubicomp technologies in support of hospital work have been created and pilot-tested. In this article, the lessons learned from these evaluations are discussed, using two criteria to classify them. The first criterion is ecological validity, namely, the extent to which the evaluation is conducted under realistic conditions. Alternatives range from controlled experiments to in situ evaluations. The article argues in particular for the advantages of intermediate approaches, which is referred to as in silico and in replica. The second criterion relates to the degree of integration of the technology with the environment, which is referred to as its pervasiveness. The evaluation grid that comes out of this exercise highlights the importance of ecological validity in evaluating ambient computing technology that supports the activities conducted in complex health care settings such as hospitals. This provides a framework for evaluating Ubihealth, which can be used to select appropriate techniques as a function of the technological and environmental complexity as well as to devise novel evaluation techniques. © Taylor & Francis Group, LLC. Source

Prokaryote respiration is expected to be responsible for more than half of the community respiration in the ocean, but the lack of a practical method to measure the rate of prokaryote respiration in the open ocean resulted in very few published data leaving the role of organotrophic prokaryotes open to debate. Oxygen consumption rates of oceanic prokaryotes measured with current methods may be biased due to pre-incubation size filtration and long incubation times both of which can change the physiological and taxonomic profile of the sample during the incubation period. In vivo INT reduction has been used in terrestrial samples to estimate respiration rates, and recently, the method was introduced and applied in aquatic ecology. We measured oxygen consumption rates and in vivo INT reduction to formazan in cultures of marine bacterioplankton communities, Vibrio harveyi and the eukaryote Isochrysis galbana. For prokaryotes, we observed a decrease in oxygen consumption rates with increasing INT concentrations between 0.05 and 1 mM. Time series after 0.5 mM INT addition to prokaryote samples showed a burst of in vivo INT reduction to formazan and a rapid decline of oxygen consumption rates to zero within less than an hour. Our data for non-axenic eukaryote cultures suggest poisoning of the eukaryote. Prokaryotes are clearly poisoned by INT on time scales of less than 1 h, invalidating the interpretation of in vivo INT reduction to formazan as a proxy for oxygen consumption rates. © 2015, Springer Science+Business Media New York. Source

Ungson Y.,Autonomous University of Baja California | Reyna M.A.,UABC
Pan American Health Care Exchanges, PAHCE

The incidence of cardiovascular diseases is rising, so more people are requiring cardiac services. The private service is very expensive; hence the public health sector is exceeded by their capacity to accomplish this demand. The proposal to solve this problem is the implementation of a wireless network based on Bluetooth (BT) for recording, monitoring and analysis of electrocardiographic signals (ECG). Three surface electrodes are placed on the chest following standardized points of triangle of Einthoven. The signals measured by electrodes are carried to Arduino UNO card, which works as an instrumentation amplifier. Then ECG signal is sent by BT from Arduino Uno to a mobile device carried by the user, so he can send it to a workstation where the ECG is processed or analyzed by an expert. This proposal would help the health sector to improve the quality of their service in the care of patients with heart diseases; also costs of care would significantly decrease. © 2013 IEEE. Source

Fimbres-Castro C.,UABC | Alvarez-Borrego J.,Carretera Ensenada Tijuana No. 3918
Proceedings of SPIE - The International Society for Optical Engineering

In this work a new methodology to recognize objects is presented. This system is invariant to position, rotation and scale by using identity vectors signatures Is obtained for both the target and the problem image. In this application, Is are obtained by means of a simplification of the main features of the original image in addition of the properties of the Fourier transform. The nonlinear correlation by using a kth law is used to obtain the digital correlation providing information on the similarity between different objects besides their great capacity to discriminate them even when are very similar. This new methodology recognizes objects in a more simple way providing a significant reduction of the image information of size m x n to one-dimensional vector of 1 x 256 consequently with low computational cost of approximately 0.02 s per image. In addition, the statistics of Euclidean distances is used as an alternative methodology for comparison of identity vectors signatures. Also, experiments were carried out in order to find the noise tolerance. The invariant to position, rotation and scale of this digital system was tested with different species of fish (real images). The results obtained have a confidence level above 95.4%. © 2013 SPIE. Source

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