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Epilepsy and Alzheimer’s disease (AD) incidence increases with age. There are reciprocal relationships between epilepsy and AD. Epilepsy is a risk factor for AD and, in turn, AD is an independent risk factor for developing epilepsy in old age, and abnormal AD biomarkers in PET and/or CSF are frequently found in late-onset epilepsies of unknown etiology. Accordingly, epilepsy and AD share pathophysiological processes, including neuronal hyperexcitability and an early excitatory–inhibitory dysregulation, leading to dysfunction in the inhibitory GABAergic and excitatory glutamatergic systems. Moreover, both β-amyloid and tau protein aggregates, the anatomopathological hallmarks of AD, have proepileptic effects. Finally, these aggregates have been found in the resection material of refractory temporal lobe epilepsies, suggesting that epilepsy leads to amyloid and tau aggregates. Some epileptic syndromes, such as medial temporal lobe epilepsy, share structural and functional neuroimaging findings with AD, leading to overlapping symptomatology, such as episodic memory deficits and toxic synergistic effects. In this respect, the existence of epileptiform activity and electroclinical seizures in AD appears to accelerate the progression of cognitive decline, and the presence of cognitive decline is much more prevalent in epileptic patients than in elderly patients without epilepsy. Notwithstanding their clinical significance, the diagnosis of clinical seizures in AD is a challenge. Most are focal and manifest with an altered level of consciousness without motor symptoms, and are often interpreted as cognitive fluctuations. Finally, despite the frequent association of epilepsy and AD dementia, there is a lack of clinical trials to guide the use of antiseizure medications (ASMs). There is also a potential role for ASMs to be used as disease-modifying drugs in AD.

This article presents a study based on evaluating different techniques to automatically recognize the basic emotions of people with Down syndrome, such as anger, happiness, sadness, surprise, and neutrality, as well as the statistical analysis of the Facial Action Coding System, determine the symmetry of the Action Units present in each emotion, identify the facial features that represent this group of people. First, a dataset of images of faces of people with Down syndrome classified according to their emotions is built. Then, the characteristics of facial micro-expressions (Action Units) present in the feelings of the target group through statistical analysis are evaluated. This analysis uses the intensity values of the most representative exclusive action units to classify people’s emotions. Subsequently, the collected dataset was evaluated using machine learning and deep learning techniques to recognize emotions. In the beginning, different supervised learning techniques were used, with the Support Vector Machine technique obtaining the best precision with a value of 66.20%. In the case of deep learning methods, the mini-Xception convolutional neural network was used to recognize people’s emotions with typical development, obtaining an accuracy of 74.8%.

Latin America is living the migration towards the digital terrestrial television (DTT) with the ISDB-Tb standard. Some countries have even had the analog blackout. In relation to the Emergency Warning Broadcast System (EWBS), the process of transmission and reception is defined. In recent years, tests have been coordinated for the process of implementing EWBS for DTT. The Common Alert Protocol (CAP) allows emergency alerts to be exchanged between different communication systems. This article presents the implementation of a CAP module in a Spatial Data Infrastructure for risk management and integration of the EWBS for DTT in a single platform for emergency alerts. A web service that contains the codes representing the cantons of Ecuador was obtained, selected through the use of a map viewer and integrated with an application that processes this information and generates the alert to be transmitted via DTT. The main objective is the storage of the information in a database, and a WEB RSS service that contains the information in conformance with CAP format. A series of experiments show successful outcomes.

Currently with the growth in traffic in wireless networks and with services that require higher speed, the challenge of reaching Shannon’s limit remains a topic of great interest, so that, seeking to increase the capacity BICM of a channel allows the use of better performing channel codes approaching the Shannon limit. The article presents an algorithm proposal to find the positions of the symbols in QAM modulations that maximize capacity, generating the Non Uniform QAM modulations. Additionally, symbol positions are presented to maximize capacity and keep average symbol energy constant. It is validated that this increase in capacity doesn’t affect the bit error rate in an AWGN channel.

Being part of the so-called “Pacific Ring of Fire” and “Belt of Low Pressure,” Ecuador is located in one area most likely to suffer seismic, volcanic, and hydrometeorological threats, which make it possible to catalog as a country with a high vulnerability. For this reason, the use of alert systems such as Emergency Warning Broadcasting System EWBS is necessary for the face of one of these threats, which can be implemented in analog and digital broadcast signals such as Digital Terrestrial Television. In an emergency, the receivers compatible with the EWBS are currently the decoders or digital televisions that include this system. They turn on automatically and emit a visual and audible alert signal that gives time to the population to act more quickly to an event. This article presents the design proposal of a receiver that replicates the warning emergency alert EWBS for digital terrestrial television with the ISDB-Tb standard, through an institutional telephone PBX, implementing an IP telephony server that receives the EWBS system and replicates it to landlines, infocast systems, and mobile phones connected to it, thus avoiding a percentage of losses in the economic and human fields.

This article presents an architectural solution to incorporate Ecuadorian sign language into the country’s free and open digital television system. Initially, a transport stream was generated with the Closed Caption service as a result of automatic transcription from audio to text, based on the regulations of the ISDB-T digital television standard, established by the Association of Broadcasting Industries and Negotiations. Later, an algorithm was developed that allows the extraction of the Closed Caption text and generates the insertion of video tracks in Ecuadorian sign language, called LSEC tracks, in the original multimedia content.

This article presents a pilot solution for the automatic insertion of video tracks in Ecuadorian sign language in the multimedia content of Digital Terrestrial Television, in order to reduce the barriers that are inserted for people with hearing disabilities when accessing to information due to their inherent difficulties in dealing with spoken and written languages. Initially, a transport type TS (Transport Stream) with Closed Caption service was generated, based on the standards of the ISDB-Tb digital television standard, established by ARIB (Association of Broadcasting Industries and Businesses). Later an algorithm is specified that allows the extraction of the Closed Caption text and generates the insertion of Ecuadorian sign language video tracks, called LSEC tracks, in the original multimedia content. These video tracks were created by the authors and represent words from the oral language, in Ecuadorian sign language through a 3D-avatar. Finally, a qualitative evaluation was carried out on the accessible content generated by the proposed solution and an analysis of the results obtained is presented.

This paper presents the performance analysis of a new TCP algorithm designed for wireless networks on a realtime scenario compared to the generic TCP algorithm. Our work considers two network scenarios: indoor and outdoor with point-multipoint topology. The performance evaluation considers the throughput, jitter and delay metrics, to obtain these metrics the intrusive traffic injection technique was used using the D-ITG software, while for the qualitative analysis the Mean Opinion Score technique was used through a survey to establish a subjective measure of the quality perceived by the user based on the different network conditions. The results indicate that the new TCP algorithm presents a significant improvement of reduction by approximately 6% compared to jitter and delay metrics.

This article presents an analysis of the performance of Non-Uniform Constellations, also known as Ultra-Multilevel, corresponding to the Digital Modulation of Quadrature Amplitude (QAM), obtained through the optimization of conventional M-QAM Constellations of order M = 16, 64, 256 1024 and 4096, from the Bit-Interleaved Coded Modulation (BICM). To estimate the behavior of a modulated bit stream with these Constellations, two metrics were used: the Signal to Noise ratio (SNR), and the Probability of bit error. Two possible scenarios for a Communications Channel were considered. The first case corresponds to a Channel with Gaussian White Additive Noise (AWGN), and the second case to an AWGN Channel that has been affected by Fading. Channel simulation was performed based on the statistical models of probability distribution, Gaussian and Rayleigh. The results for each case were obtained with the Monte Carlo method. The performance results of the Conventional QAM Constellations with the results of the Non-Uniform QAM Constellations were compared, and it is determined which of them behave optimally with each value of a wide range of SNR values.

El siguiente trabajo propone articular paradigmasteóricos disímiles que a la vez provienen de distintasdisciplinas para analizar políticas sociales. Concretamente,se intenta incorporar elementos conceptualesdel institucionalismo centrado en actores de Scharpf(1997) – que a su vez se vale de elementos y herramientasde la teoría de la acción racional y la teoríade la acción cognitiva de Boudon (2003) – y utilizarloen el análisis de políticas públicas que recepten,al menos en su diseño, el enfoque de derechos humanos.A tal efecto, se hará un estudio exploratoriode un programa social, el PROGRESAR, el cualcumple las condiciones para ser analizado con elmarco de análisis propuesto.

El presente artículo muestra una solución al desarrollo automático de aplicaciones interactivas Ginga-NCL para la Televisión Digital Terrestre, a partir de plantillas prediseñadas. Productores de televisión y gente relacionada con este medio de comunicación masivo, no conocen o simplemente no tienen las herramientas necesarias para la creación de aplicaciones interactivas, en muchos casos ni siquiera se conoce la existencia de una plataforma para el desarrollo de las mismas. Es por esta razón que se propone una metodología totalmente nueva y amigable para el usuario, la cual permita generar aplicaciones interactivas sin tener el conocimiento técnico ni las habilidades de programación que implica su creación. La reducción del tiempo en la generación de aplicaciones, disminución de capital de inversión en la preparación y adiestramiento del personal, cambios on-air en la programación interactiva del canal de televisión, son algunos de los resultados que trae consigo este sistema.

El dinero electrónico es un medio de pagos implementado por el Banco Central del Ecuador, el cual permite a las personas realizar transacciones comerciales desde su celular; este se puede utilizar para efectuar pagos en grandes establecimientos comerciales denominados “macro agentes”, entre los que se encuentran las cadenas de supermercados, pero también se puede utilizar para realizar consumos en todo tipo de negocios particulares como restaurantes, tiendas, etc., mediante transferencias de “persona a persona” denominadas P2P. Sin embargo, el sistema de dinero electrónico, SDE, tal como está concebido induce ciertas desventajas competitivas entre los negocios particulares y los macro agentes; la principal radica en que los primeros no cuentan con un sistema que les permita llevar registro de los cobros efectuados con dinero electrónico. El presente artículo detalla la creación de una plataforma tecnológica que permite actualmente a todo tipo de negocios y personas llevar registro de sus transacciones P2P, mediante una solución automatizada con capacidad de generar balances de los pagos recibidos, los cuales se pueden visualizar fácilmente a través de Internet. Para esto se llevó a cabo un análisis profundo del funcionamiento del SDE, con el fin de establecer una solución eficiente al problema, procurando siempre optimizar recursos.

Electronic money is a payment tool implemented by the Ecuador’s Central Bank, it allows people to make commercial transactions using their cellphones; it can be used to pay into big chain stores like supermarkets, known as "macro agents", but it also can be employed for the consumption of goods and services into particular businesses such as restaurants or small shops by using “person to person” transfers known as P2P. However, the particular businesses present some disadvantages compared to the macro agents, the main one is the lack of a system that allows them to have a record of the transactions made with electronic money. This article details the design and implementation of a technological platform that allows all types of businesses and people to keep records of their P2P transactions into an automated system with the ability of generating payment’s balance sheets which can be easily viewed through Internet. A research was conducted in order to look for the most efficient technical solution to optimize the available resources. The use of this platform as an external tool extends the capabilities currently provided by the electronic money system., El dinero electrónico es un medio de pagos implementado por el Banco Central del Ecuador, el cual permite a las personas realizar transacciones comerciales desde su celular; este se puede utilizar para efectuar pagos en grandes establecimientos comerciales denominados “macro agentes”, entre los que se encuentran las cadenas de supermercados, pero también se puede utilizar para realizar consumos en todo tipo de negocios particulares como restaurantes, tiendas, etc., mediante transferencias de “persona a persona” denominadas P2P. Sin embargo, el sistema de dinero electrónico, SDE, tal como está concebido induce ciertas desventajas competitivas entre los negocios particulares y los macro agentes; la principal radica en que los primeros no cuentan con un sistema que les permita llevar registro de los cobros efectuados con dinero electrónico. El presente artículo detalla la creación de una plataforma tecnológica que permite actualmente a todo tipo de negocios y personas llevar registro de sus transacciones P2P, mediante una solución automatizada con capacidad de generar balances de los pagos recibidos, los cuales se pueden visualizar fácilmente a través de Internet. Para esto se llevó a cabo un análisis profundo del funcionamiento del SDE, con el fin de establecer una solución eficiente al problema, procurando siempre optimizar recursos.

This work shows the implementation of a hybrid STB (Set Top Box) that receives real-time digital signals for ISDB-Tb and IPTV. The implementation integrates middleware GINGA for interactive DTT applications based on low cost platforms. The features of the hardware platform for this implementation are analyzed so that they can integrate USB reception modules for digital TV, support interactive middleware versions and also be compatible with TV playback software by means of internet protocols. After the analysis and evaluation, we found that the most suitable board to achieve this implementation was Raspberry Pi 3. The development of the Android mobile graphic interface is also shown, which emulates a remote control by Bluetooth technology. Finally, the results of the implemented hybrid STB’s evaluation are presented; evaluation performed by reception tests of DTT channels with interactivity and free IPTV channels. Also, quantitative readings were made to test the performance and correct operation, as well as qualitative MOS polls to get the quality of user experience when handling the decoder.

The results of transmission and reception broadcast tests of the Emergency Warning Broadcast System (EWBS) for Digital Terrestrial Television in the city of Quito-Ecuador with the ISBD-T standard are presented in this paper, in coordination with government agencies and private companies. The system consists of an EWBS server developed and implemented by the authors, which modifies the text overlay message and the PSI tables for some-emergency-codes transmission, as established in the EWBS international harmonization document, while re-configuring the multiplexing and transmission stage of the television station. The tests were carried out in two stages, on the one hand working directly with the multiplexers and modulators of digital terrestrial television from Pichincha hill, and on the other hand from television station with a microwave transport network to Pichincha hill. It was possible make the activation of the EWBS receivers in the coverage region, select codes, and reception of the overlay message, with an nearly imperceptible delay in the complete system, within real time requirements.

In this paper we propose the implementation of the digital terrestrial television receiver under the ISDB-Tb (Integrated Services Digital Broadcasting-Terrestial Build-in) standard for the mobile service in the device based in Radio Defined by Software USRP (Universal Software Radio Peripheral). The implemented reception system allows recovering the digital signal in narrow band to observe in real time the different channels and at the same time determine its quality through objective measures. A mathematical algorithm was implemented for the perfect synchronization in time and frequency of the signal of OFDM (Orthogonal Frequency Division Multiplexing), reducing the harmful effects of channel and increasing receiver efficiency.

This paper analyzes the reverse link performance of wireless networks in presence of co-channel interference on AWGN and Rayleigh fading channels and M-QAM modulation schemes. Simple and precise close-form analytic expressions for mean symbol error probability are derived. The proposed expressions of the analytic model developed to evaluate the performance of those systems are verified by the results of computer simulations.

This project presents the analysis and performance evaluation for digital terrestrial television transmitter stations for mobile broadcasting using ISDB-T standard over AWGN and fading channel. A main broadcast transmitter with a secondary transmitter has been evaluated. The second station works with a lower power regarding the main broadcast transmitter, for this project with a 100:1 ratio. Under this scenario, two working options has been defined: (i) both stations transmit the same information, where the secondary station was considered as a repeater station, and (ii) both stations transmit different information, building an environment of co-channel interference. The performance by the bit error rate as a function of the receiver location was presented. The simulation and theoretical results show the improvement or deterioration of the signal, respectively to the working options stablished for the ISDB-T standard's A layer in order to validate repeater stations for digital terrestrial television mobile broadcasting.

espanolEn este estudio presentamos cuatro pinturas sobre cobre de ascendencia flamenca, una de ellas firmada por Willem van Herp (1614-1677), a quien tambien atribuimos las restantes. Obras tal vez de la segunda mitad del siglo XVII e inspiradas en Rubens y Teniers el Viejo que, en su mayoria, pertenecieron a Eusebio Lillo y hoy se custodian en el Museo O'Higginiano y de Bellas Artes de Talca (Chile). EnglishIn this study we present four oil on copper paintings of Flemish descent, one by Wil lem van Herp (1614-1677), whom we also attribute the remaining ones. His works may date back to the second half of the 17th century and are inspired by Rubens and Teniers the Elder: Most of them belonged to Eusebio Lillo and nowadays they are kept at the O'Higgins' and Fine Arts Museum in Talca (Chile).

This article presents a mobility application of navegation directed to people with visual deficiency and disability. Visually disabled people cope with daily challenges in mobility and in their automony. VOICE-TOUCH GPS is an application that has two forms in order to interact with them. The first one lets the person use a smartphone with touch screen to have an auditory feedback. The second one interacts by means of a synthesizer which generates a text by voice and vice-versa. The application presents a graphic interface easy to use along with the help of a GPS. It will help the user know the latest location, the nearest bus stop, buses routes, make phone calls and send messages predetermined to the location. Furthermore, this article presents the functions of the application, requirements of functioning, social impact and the results obtained in people with total and partial visual deficiency in Ecuador.

The present article describes the creation of a MPEG-2 Transport Stream (TS)/Broadcast Transport Stream (BTS) Analyzer for Digital Television. This analyzer recognizes TS and BTS files in a decimal or hexadecimal format and it shows the components of the PSI (Program Service Information)/SI (Service Information) Tables, such as: Program Association Table (PAT), Program Map Table (PMT), Network Information Table (NIT), and Service Descriptor Table (SDT); in the case of the BTS files it also shows the content of the Transmission and Multiplexing Configuration (TMCC) table. The software has a package search system where you can look for a package through his PID (Program Identification) number or his package number. It also allows surfing between all the packages or the packages with the same PID number.

This paper shows the design, implementation and evaluation of an algorithm that allows the extraction of Transport Stream's (TS) data section for Digital Terrestrial Television (DTT), with the organization in a hierarchical file system and directories based on MPEG-2 standard ISO-13818-6: Extension for Digital Storage Media Command and Control (DSM-CC), in order to fully recover the media from interactive applications contained by the MPEG-2 TS stream. To check the validity of the algorithm, it was implemented in a software to evaluate the application extraction of different TS, verifying its correct operation, as it successfully recovered all directories and files from interactive applications.

Two important aspects about UMTS/HSPA (Universal Mobile Telecommunications Service/High Speed Packet Access) and LTE (Long Term Evolution) systems are analyzed. First, an analysis of the frequency bands allocated in Ecuador for the cellular systems is made. Then, expressions for the mean bit error rate in a AWGN channel and the presence of co-channel interference is carried out both for WCDMA (Wideband - Code Division Multiple Access) and OFDMA (Orthogonal Frequency Division Multiple Access). Because the necessity of support the increase of traffic due to the emergence of new mobile broadband services, the deployment of LTE networks is necessary. Hence, in Ecuador, new spectrum bands were allocated to the cellular systems. Initially, the bands of 850 MHz and 1900 MHz were available for GSM (Global System for Mobile Communications), EDGE (Enhanced Date Rates For GSM Evolution) and UMTS/HSPA techniques. Nowadays, the country also has the bands of 700 MHz, 1700–2100 MHz (AWS - Advanced Wireless Services) and 2.5 GHz to deploy cellular systems. Also, it is shown that WCDMA provides higher immunity against the co-cell interference, but due to the computational simplicity of the OFDMA technique, it is employed in the new cellular systems.

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 evaluate the performance of the TCP protocol. The results showed that the modified TCP protocol with a window of 15 is more appropriate, however, it was noted the need to optimize the sensing mechanism of the error type to improve wireless TCP performance by using cross layer design. With the intention of optimizing the TCP performance, we have mathematically modeled the RTT value that should be used to calculate the appropriate RTO.

En este artículo se realiza el análisis de una Red Ad-Hoc MANET Móvil bajo el estándar IEEE 802.15.4 utilizando Network Simulator 2.32 (NS) en función del Throughput y el Tiempo Medio parametrizados por el número de nodos para una frecuencia de 2,4 GHz y una tasa de transmisión de 250 kbps. En el canal es usado el modelo de propagación de dos rayos.

In this article, the normalized throughput and the normalized average delay for the transport layer at the reverse link of multicellular CDMA systems are obtained. For the transport layer the Transport Control Protocol (TCP) with consecutive retransmissions control is employed. On the radio link layer three TCP error control strategies are evaluated and compared. The first strategy is based on the radio-link-protocol (RLP), which breaks down the TCP packets into smaller blocks and uses an error detecting procedure to protect those RLP blocks. The second strategy uses forward-error-control (FEC) procedure at the radio link layer. In this case, two kinds of FEC are compared: convolutional and turbo coding. The third one is a hybrid between the first and second strategies with coding at the RLP layer. A frequency-selective Rayleigh fading channel with shadowing and power control loop error is considered.

This article describes the performance evaluation of a new wireless TCP algorithm in real environments, in order to identify the advantages and disadvantages of its operation. We evaluate the proposed wireless TCP algorithm with respect to generic TCP, considering an intrusive technique by using traffic injection. These tests were performed over point-to-point WiFi and WiMAX links in out-door and in-door environments. The proposed amendment for wireless TCP was incorporated in a virtual machine under Linux operating system, and using D-ITG tool for the traffic injections. We assess the performance of the proposed algorithm in terms of the main parameters of Quality of Service (QoS) as throughput, delay, and jitter. Our primary results demonstrate that our new proposal of the TCP algorithm presents better results in comparison with the generic TCP referred to all terms of QoS in wireless environments.

The evolution of wireless networks and the low cost of WiFi technology, have enabled a promising scenario for deployment of these kind of networks in rural areas, as an effective alternative to interconnect distanced sites above tens kilometers. This work presents the results of the performance evaluation of a network with WiLD technology, based on simulation and a deployment in the Andean region of Ecuador, between a station located at Special Forces in Latacunga with an station located at Cerro Pilisurco, distanced approximately 32 km. The main difference between the results obtained in simulation and in the experimental deployment refers, while the simulator allowed to change values corresponding to the physical and link layer, we were unable to control values concerning to delays due to processing and the propagation model, which did not consider regional climatic factors. The link presents a normalized throughput of 0.3 and a mean delay of 5s.

This article presents on analytical performance analyzes about QPSK, 16QAM and 64 QAM modulations and error correcting codes defined in ISDB-T system over AWGN channels. Simple and precise close-form analytic expressions related to byte error probability for the transport stream layer, as a function of the energy per modulated symbol for Viterbi hard and soft decision decoding are derived. The proposed expressions of the analytic model developed to evaluate the performance of the ISDB-T system are verified by the results of computer simulations.

This article describes the analysis of return channel for digital terrestrial television (DTT), through the development of interactive application called Shopping Car buying and selling. Using the middleware Ginga-NCL, Lua and MySQL, to get evidence of the return path for the interactive application and determines the capacity of server performance.