The analysis of biomedical signals demonstrating complexity through recurrence plots is challenging. Quantification of recurrences is often biased by sojourn points that hide dynamic transitions. To overcome this problem, time series have previously been embedded at high dimensions. However, no one has quantified the elimination of sojourn points and rate of detection, nor the enhancement of transition detection has been investigated. This paper reports our on-going efforts to improve the detection of dynamic transitions from logistic maps and fetal hearts by reducing sojourn points. Three signal-based recurrence plots were developed, i.e. embedded with specific settings, derivative-based and m-time pattern. Determinism, cross-determinism and percentage of reduced sojourn points were computed to detect transitions. For logistic maps, an increase of 50% and 34.3% in sensitivity of detection over alternatives was achieved by m-time pattern and embedded recurrence plots with specific settings, respectively, and with a 100% specificity. For fetal heart rates, embedded recurrence plots with specific settings provided the best performance, followed by derivative-based recurrence plot, then unembedded recurrence plot using the determinism parameter. The relative errors between healthy and distressed fetuses were 153%, 95% and 91%. More than 50% of sojourn points were eliminated, allowing better detection of heart transitions triggered by gaseous exchange factors. This could be significant in improving the diagnosis of fetal state.

Abstract-Nearly 20 million premature and Low Birth Weight infants are born each year in developing countries, 4 million die within their first month. These deaths occur due to the unavailability or unreliability of traditional incubators. Moreover, although Telemedicine is helpful in rural areas, the shortage of healthcare providers have made it inaccessible in both basic healthcare. Thereby, traditional preterm baby and low-birth weight incubators and therapeutic techniques lack Telemedicine communication and feedback. The aim of our project is to develop an advanced portable and wireless-base incubator. We tend to provide an affordable, feasible, patient friendly and reliable premature baby incubator especially in low-income countries. The project focuses on the premature babies in the third trimester of pregnancy. The design is based on Wi-Fi and infrared technologies that measure the essential parameters that must be controlled for preemies. These parameters include the heart rate, oxygen level in the blood and temperature. Results showed the advanced design building blocks. The response of the generated power-voltage proves that the power can be regulated by the voltage. The thermal isolation can decrease the thermal lose and increase the time needed to drop temperature 6 times. In the room temperature of premature infant, 20 o C and 45 o C, the resistance decreases from 12.69 kΩ to 4.82 kΩ. The voltage and the temperature were inversely proportional. The heaters were efficient when tested on water. One of the major advantages of the device is that it surpasses existing techniques. As a future prospect more electronic components needs to be tested and features needs to be extracted.

International audience—Recurrence plots are nonlinear tools used to visual-ize the behavior of trajectories of Dynamic Systems. Occurrence of false points known as 'sojourn points' have biased recurrence plots. To solve this contentious issue, the use of high embedding dimension was proposed. However it required a lot of computa-tion and was based on the phase space. For that, we proposed in this paper to compare four quantification techniques, by dropping out sojourn points from the recurrence test of time series. Firstly, a recurrence plot and embedding of two were used as reference methods. Secondly, the number of points in the pattern used for testing recurrences was increased and a m-pattern recurrence plot was introduced. Thirdly, a single system's output and its corresponding derivative were proposed. Numerical inference showed that it was sufficient to work on a single measurement regardless of the degrees of freedom of the considered system and thus the embedding dimension. The proposed techniques succeeded in eliminating sojourn points. They provided a tool for a clean unbiased recurrence plots which permits better analysis of chaotic dynamic systems