Model updating using genetic algorithms with sequential niche technique

The authors would like to express their gratitude to organizations and people that supported this research. Piotr Omenzetter’s work within the Lloyd’s Register Foundation Centre for Safety and Reliability Engineering at the University of Aberdeen is supported by Lloyd’s Register Foundation. The Foundation helps to protect life and property by supporting engineering-related education, public engagement and the application of research. Ben Ryder of Aurecon and Graeme Cummings of HEB Construction assisted in obtaining access to the bridge and information for modelling. Luke Williams and Graham Bougen, undergraduate research students, assisted with testing.

Sistemas de cálculo, análise e operação virtual: interferências de campos elétricos e magnéticos produzidas por estações radio base de acesso múltiplo por divisão de código em banda larga - WCDMA

In this work it was developed mathematical resolutions taking as parameter maximum intensity values for the interference analysis of electric and magnetic fields and was given two virtual computer system that supports families of CDMA and WCDMA technologies. The first family were developed computational resources to solve electric and magnetic field calculations and power densities in Radio Base stations , with the use of CDMA technology in the 800 MHz band , taking into account the permissible values referenced by the Commission International Protection on non-Ionizing Radiation . The first family is divided into two segments of calculation carried out in virtual operation. In the first segment to compute the interference field radiated by the base station with input information such as radio channel power; Gain antenna; Radio channel number; Operating frequency; Losses in the cable; Attenuation of direction; Minimum Distance; Reflections. Said computing system allows to quickly and without the need of implementing instruments for measurements, meet the following calculated values: Effective Radiated Power; Sector Power Density; Electric field in the sector; Magnetic field in the sector; Magnetic flux density; point of maximum permissible exposure of electric field and power density. The results are shown in charts for clarity of view of power density in the industry, as well as the coverage area definition. The computer module also includes folders specifications antennas, cables and towers used in cellular telephony, the following manufacturers: RFS World, Andrew, Karthein and BRASILSAT. Many are presented "links" network access "Internet" to supplement the cable specifications, antennas, etc. . In the second segment of the first family work with more variables , seeking to perform calculations quickly and safely assisting in obtaining results of radio signal loss produced by ERB . This module displays screens representing propagation systems denominated "A" and "B". By propagating "A" are obtained radio signal attenuation calculations in areas of urban models , dense urban , suburban , and rural open . In reflection calculations are present the reflection coefficients , the standing wave ratio , return loss , the reflected power ratio , as well as the loss of the signal by mismatch impedance. With the spread " B" seek radio signal losses in the survey line and not targeted , the effective area , the power density , the received power , the coverage radius , the conversion levels and the gain conversion systems radiant . The second family of virtual computing system consists of 7 modules of which 5 are geared towards the design of WCDMA and 2 technology for calculation of telephone traffic serving CDMA and WCDMA . It includes a portfolio of radiant systems used on the site. In the virtual operation of the module 1 is compute-: distance frequency reuse, channel capacity with noise and without noise, Doppler frequency, modulation rate and channel efficiency; Module 2 includes computes the cell area, thermal noise, noise power (dB), noise figure, signal to noise ratio, bit of power (dBm); with the module 3 reaches the calculation: breakpoint, processing gain (dB) loss in the space of BTS, noise power (w), chip period and frequency reuse factor. Module 4 scales effective radiated power, sectorization gain, voice activity and load effect. The module 5 performs the calculation processing gain (Hz / bps) bit time, bit energy (Ws). Module 6 deals with the telephone traffic and scales 1: traffic volume, occupancy intensity, average time of occupancy, traffic intensity, calls completed, congestion. Module 7 deals with two telephone traffic and allows calculating call completion and not completed in HMM. Tests were performed on the mobile network performance field for the calculation of data relating to: CINP , CPI , RSRP , RSRQ , EARFCN , Drop Call , Block Call , Pilot , Data Bler , RSCP , Short Call, Long Call and Data Call ; ECIO - Short Call and Long Call , Data Call Troughput . As survey were conducted surveys of electric and magnetic field in an ERB , trying to observe the degree of exposure to non-ionizing radiation they are exposed to the general public and occupational element. The results were compared to permissible values for health endorsed by the ICNIRP and the CENELEC .

Quantitative Analysis of Kilohertz-Frequency Neurostimulation

Mainstream electrical stimulation therapies, e.g., spinal cord stimulation (SCS) and deep brain stimulation, use pulse trains that are delivered at rates no higher than 200 Hz. In recent years, stimulation of nerve fibers using kilohertz-frequency (KHF) signals has received increased attention due to the potential to penetrate deeper in the tissue and to the ability to block conduction of action potentials. As well, there are a growing number of clinical applications that use KHF waveforms, including transcutaneous electrical stimulation (TES) for overactive bladder and SCS for chronic pain. However, there is a lack of fundamental understanding of the mechanisms of action of KHF stimulation. The goal of this research was to analyze quantitatively KHF neurostimulation.

We implemented a multilayer volume conductor model of TES including dispersion and capacitive effects, and we validated the model with in vitro measurements in a phantom constructed from dispersive materials. We quantified the effects of frequency on the distribution of potentials and fiber excitation. We also quantified the effects of a novel transdermal amplitude modulated signal (TAMS) consisting of a non-zero offset sinusoidal carrier modulated by a square-pulse train. The model revealed that high-frequency signals generated larger potentials at depth than did low frequencies, but this did not translate into lower stimulation thresholds. Both TAMS and conventional rectangular pulses activated more superficial fibers in addition to the deeper, target fibers, and at no frequency did we observe an inversion of the strength-distance relationship. In addition, we performed in vivo experiments and applied direct stimulation to the sciatic nerve of cats and rats. We measured electromyogram and compound action potential activity evoked by pulses, TAMS and modified versions of TAMS in which we varied the amplitude of the carrier. Nerve fiber activation using TAMS showed no difference with respect to activation with conventional pulse for carrier frequencies of 20 kHz and higher, regardless the size of the carrier. Therefore, TAMS with carrier frequencies >20 kHz does not offer any advantage over conventional pulses, even with larger amplitudes of the carrier, and this has implications for design of waveforms for efficient and effective TES.

We developed a double cable model of a dorsal column (DC) fiber to quantify the responses of DC fibers to a novel KHF-SCS signal. We validated the model using in vivo recordings of the strength-duration relationship and the recovery cycle of single DC fibers. We coupled the fiber model to a model of SCS in human and applied the KHF-SCS signal to quantify thresholds for activation and conduction block for different fiber diameters at different locations in the DCs. Activation and block thresholds increased sharply as the fibers were placed deeper in the DCs, and decreased for larger diameter fibers. Activation thresholds were > 5 mA in all cases and up to five times higher than for conventional (~ 50 Hz) SCS. For fibers exhibiting persistent activation, the degree of synchronization of the firing activity to the KHF-SCS signal, as quantified using the vector strength, was low for a broad amplitude range, and the dissimilarity between the activities in pairs of fibers, as quantified using the spike time distance, was high and decreased for more closely positioned fibers. Conduction block thresholds were higher than 30 mA for all fiber diameters at any depth and well above the amplitudes used clinically (0.5 – 5 mA). KHF-SCS appears to activate few, large, superficial fibers, and the activated fibers fire asynchronously to the stimulation signal and to other activated fibers.

The outcomes of this work contribute to the understanding of KHF neurostimulation by establishing the importance of the tissue filtering properties on the distribution of potentials, assessing quantitatively the impact of KHF stimulation on nerve fiber excitation, and developing and validating a detailed model of a DC fiber to characterize the effects of KHF stimulation on DC axons. The results have implications for design of waveforms for efficient and effective nerve fiber stimulation in the peripheral and central nervous system.

A stereo-image analysis JAVA software with links to executable and source code

Scientists planning to use underwater stereoscopic image technologies are often faced with numerous problems during the methodological implementations: commercial equipment is too expensive; the setup or calibration is too complex; or the imaging processing (i.e. measuring objects in the stereo-images) is too complicated to be performed without a time-consuming phase of training and evaluation. The present paper addresses some of these problems and describes a workflow for stereoscopic measurements for marine biologists. It also provides instructions on how to assemble an underwater stereo-photographic system with two digital consumer cameras and gives step-by-step guidelines for setting up the hardware. The second part details a software procedure to correct stereo-image pairs for lens distortions, which is especially important when using cameras with non-calibrated optical units. The final part presents a guide to the process of measuring the lengths (or distances) of objects in stereoscopic image pairs. To reveal the applicability and the restrictions of the described systems and to test the effects of different types of camera (a compact camera and an SLR type), experiments were performed to determine the precision and accuracy of two generic stereo-imaging units: a diver-operated system based on two Olympus Mju 1030SW compact cameras and a cable-connected observatory system based on two Canon 1100D SLR cameras. In the simplest setup without any correction for lens distortion, the low-budget Olympus Mju 1030SW system achieved mean accuracy errors (percentage deviation of a measurement from the object's real size) between 10.2 and -7.6% (overall mean value: -0.6%), depending on the size, orientation and distance of the measured object from the camera. With the single lens reflex (SLR) system, very similar values between 10.1% and -3.4% (overall mean value: -1.2%) were observed. Correction of the lens distortion significantly improved the mean accuracy errors of either system. Even more, system precision (spread of the accuracy) improved significantly in both systems. Neither the use of a wide-angle converter nor multiple reassembly of the system had a significant negative effect on the results. The study shows that underwater stereophotography, independent of the system, has a high potential for robust and non-destructive in situ sampling and can be used without prior specialist training.

Under One Umbrella: Problems of Internet Retransmissions of Broadcasts and Implications for New Audiovisual Content Services

The development of broadband Internet connections has fostered new audiovisual media services and opened new possibilities for accessing broadcasts. The Internet retransmission case of TVCatchup before the CJEU was the first case concerning new technologies in the light of Art. 3.1. of the Information Society Directive. On the other side of the Atlantic the Aereo case reached the U.S. Supreme Court and challenged the interpretation of public performance rights. In both cases the recipients of the services could receive broadcast programs in a way alternative to traditional broadcasting channels including terrestrial broadcasting or cable transmission. The Aereo case raised the debate on the possible impact of the interpretation of copyright law in the context of the development of new technologies, particularly cloud based services. It is interesting to see whether any similar problems occur in the EU. The „umbrella” in the title refers to Art. 8 WCT, which covers digital and Internet transmission and constitutes the backrgound for the EU and the U.S. legal solutions. The article argues that no international standard for qualification of the discussed services exists.

Rapports différenciés aux médias entre trois générations de femmes réfugiées au Québec

Cette thèse présente l’analyse des propos de trois générations de femmes réfugiées au Québec sur les manières dont ces femmes s’exposent, s’identifient et s’approprient le discours des médias pour ensuite en discuter entre elles. L’analyse permet de cerner certaines de leurs pratiques d’insertion et d’adaptation à un nouveau milieu de vie. L’immigration favorise de plus en plus l’éclosion des « cultures de la mixité », lesquelles représentent un enjeu incontournable en matière d’intégration. Quant aux médias, ils sont une source incontournable d’accès à l’information et à la culture. Le développement des techniques de transmission telles les réseaux câblés, le satellite de diffusion directe, Internet et le numérique permet au consommateur de médias, quel que soit son origine, de s’approprier de façon personnelle les produits culturels qui en retour déterminent la participation à la vie active dans la société hôte. Cette nouvelle intégration culturelle se transmet-elle aisément au sein des générations d’immigrantes? Cette thèse découle aussi d’un projet plus vaste sur les transmissions intergénérationnelles des savoirs, des pratiques et de l’entraide entre trois générations de femmes réfugiées au Québec (Vatz Laroussi, Guilbert & al. CRSH, 2009-2012). Étudier les transmissions de savoirs au sein des familles immigrantes, c’est reconnaitre avec les auteurs contemporains l’importance de la transmission et de la circulation des histoires personnelles s’inscrivant dans une histoire familiale et sociale de l’époque a méthodologie adoptée s’appuie sur les entretiens semi-directifs, le commentaire réflexif ainsi que l’analyse de contenu. La démarche méthodologique a été empruntée au projet principal. Les entretiens réalisés auprès des familles de réfugiés établis dans plusieurs régions du Québec (Sherbrooke, Joliette, Québec et Montréal) ont été réalisés par une équipe pluridisciplinaire, multiculturelle et féminine. L’originalité de cette recherche se trouve entre autres dans la collecte d’information qui s’est faite auprès de trios générationnels (grand-mère, mère et fille). Chaque membre du trio a été rencontré de façon individuelle et par la suite, le trio s’est formé pour une dernière entrevue de groupe. Ainsi, une analyse thématique des discours des répondants a été réalisée. Cette analyse a permis de mettre en perspective divers éléments proéminents relatifs à la relation entre les médias et chaque membre du trio générationnel. Il a été constaté que les médias sont appréhendés différemment par chaque membre du trio, que des médias comme la télévision et l’Internet sont les plus prisés par les jeunes et ils servent à la fois de fenêtre sur le pays d’accueil, d’ouverture sur le monde et d’expression de soi-même face aux frustrations vécues au Québec. En dernier lieu, une analyse de la question de la transmission intergénérationnelle au prisme des médias entre les trois générations de femme réfugiée a été faite. On constate que dans les trios, la transmission n’est pas unidirectionnelle. Elle va dans tous les sens. Sortant des sentiers battus elle devient un espace de création.

Consumo del internet de los estudiantes del Colegio Herlinda Toral

El uso de Internet aparece estrechamente vinculado con la posibilidad de comunicarse a través de un soporte digital. Las tecnologías digitales permiten una gran velocidad de comunicación. Este medio acorta las distancias, uno puede conectarse a nivel de todo el mundo y a toda hora, sin embargo crea enlaces de amistad con muchas personas de diferente sexo, edad, sin lugar a duda lo que los jóvenes buscan a través de estos canales. Los programas de entretenimiento están marcando el ritmo de vida cotidiana en los jóvenes que lo utilizan, porque se ven prestos a utilizar constantemente las redes sociales y orienta a las personas en general a consumir este medio, ya que al indagar se encuentran con otras personas que en ese momento se encuentran en línea, o al no estar comunicados se dejan mensajes que exigen una respuesta. Internet nos ofrece numerosas alternativas en comparación con otros medios: se accede a través de líneas de conexión, módems con cable, acceso fijo sin cable. Son sistemas alimentados con banda ancha en telecomunicaciones a la transmisión de datos la cual se envía información, se incrementa la velocidad de transmisión efectiva, que permite que Internet llegue a todos los hogares

Acoplamiento flexible de seguridad frente a impactos

Acoplamiento flexible de seguridad frente a impactos, del tipo de los utilizados en eslabones de brazos robóticos y que incorporan algún mecanismo que permite variar el nivel de carga a partir del cual entra en funcionamiento la flexibilidad del acoplamiento. El acoplamiento incorpora una pieza (1) y una pieza (2) cilíndricas huevas enfrentadas por sus bases, las cuales disponen de una multitud de hendiduras (5) y protuberancias (6) que insertan perfectamente. Un resorte helicoidal (3) apoya en la cara interior de la base de la pieza (1) y en el otro extremo del resorte (3) se fija el extremo de un cable (8), el cual atraviesa las bases de las piezas (1) y (2). El otro extremo del cable (8) se fija a la cabeza de un tornillo (7) roscado a la base de la pieza (2) y que permite tensar el cable (8) y comprimir el resorte (3).

Magnetómetro para medida de campos electromagnéticos débiles en la banda ELF

La invención comprende un sistema para la medición de campos electromagnéticos débiles, en la banda de frecuencias comprendida entre 1 a 100 Hz, donde se localizan señales derivadas de la resonancia natural que ocurre entre la tierra y la ionosfera, las resonancias de Schumann. El sistema está compuesto por un núcleo de material ferromagnético (1) y un conjunto de bobinas separadas entre sí (2), conectadas mediante cables unifilares (8). Un cable de par trenzado (3) conecta el sensor a un sistema electrónico de medida (4) compuesto por un amplificador diferencial (5) al que se acoplan cada par trenzado, en una bifurcación coaxial con las mallas comunes (20), (21) mediante conectores coaxiales (22), (23) y con salida a un convertidor analógico digital (6). La geometría, estructura y materiales del sistema, le confieren sus propiedades de sensibilidad y ancho de banda.

A study of the electrical basis for the inhibition and excitation in autonomically innervated smooth muscle

The aim of this thesis was to investigate the electrical and mechanical responses to inhibitory non-adrenergic noncholinergic (NANC) nerve stimulation in the bovine retractor penis muscle (BRP) and compare them with those to an inhibitory extract made from this muscle. The extract may contain the NANC inhibitory transmitter of the BRP and possibly of other smooth muscles. Because of species differences in the electrical response to NANC nerves in the rat and rabbit anococcygeus the effects of the extract on these tissues was also investigated. Prior to the investigation of the extract, both the excitatory and inhibitory responses to field stimulation in the BRP, and the effects of passive membrane potential displacement were studied using conventional intra- or extracellular (sucrose gap) recording techniques. The majority of cells in the BRP were electrically quiescent independent of the resting tone. The most frequent (in approximately 25% of preparations) form of spontaneous activity, oscillations in membrane potential and tone, may represent a pacemaker activity. The BRP had cable properties; the time constant and space constant indicated a high membrane resistance. In the absence of tone, field stimulation of the BRP evoked excitatory junction potentials (ejps) in every cell impaled and contractions, graded with the strength, frequency and number of pulses; spikes were not observed. Guanethidine (1-3 x 10-5M) abolished the ejps and contractions, confirming their adrenergic origin. Noradrenaline added exogenously depolarised and contracted the muscle. These effects were blocked by the a-adrenoceptor antagonists, phentolamine and prazosin. However, phentolamine (2.5x 10-6M) inhibited the contraction without reducing the ejp significantly. These effects may be independent of adrenoceptor blockade or the ejp may be mediated by a substance other than noradrenaline (e.g. ATP) released from adrenergic nerves. Prazosin (1.4 x lO-6M) failed to block either the ejp or contraction, indicating the possible existence of two types of adrenoceptor in the BRP; one activated by neuronally-released and the other by exogenously-added noradrenaline. ATP, a contaminant in the extract, also depolarised and contracted the BRP. Physostigmine reduced whilst atropine enhanced the ejps and contractions without similarly affecting the response to exogenous noradrenaline. This confirmed the presence of a cholinergic inhibitory innervation acting on the excitatory adrenergic fibres (Klinge and Sjostrand, 1977). TEA (1 x lO-4M) enhanced the ejp and contraction. Higher concentrations (0.5 to 10 x 10-3M) depolarised, increased the tone and evoked electrical and mechanical oscillations but no spikes. The depolarisation and contraction to exogenous noradrenaline were not enhanced, indicating that TEA acts on the adrenergic nerves. Some post-synaptic effect to block K+ channels also seems likely. The relationship between ejp amplitude and membrane potential in the double sucrose gap was linear and indicated a reversal potential more positive than -30mV. Electrotonic pulse amplitude decreased during the ejp, indicating an increased membrane conductance. Ejps and contractions were reduced following the replacement of the NaCl of the Krebs solution with sodium glutamate. This may be due to the effects of glutamate itself (e.g. Ca2+ chelation) rather than reduction in the membrane Cl- gradient. Tone usually developed spontaneously and was accompanied by membrane depolarisation (from -53 to -45mV) which may open voltage-dependent channels, causing Ca2+ entry and/or its release from intracellular binding sites. Field stimulation produced inhibitory potentials (ijps) and relaxations graded with the strength and number of pulses but showing little frequency dependence. Rebound depolarisation and contraction often followed the ijp and relaxation. Tetrodotoxin (3 x IO-6M), but not adrenergic or cholinergic antagonists, abolished the ijp and relaxation, confirming their non-adrenergic non-cholinergic neurogenic nature. The extract, prepared and acid-activated as described by Gillespie, Hunter and Martin (1981), hyperpolarised and relaxed the BRP, as did sodium nitroprusside and adenosine triphosphate (ATP). Unlike the activated extract or sodium nitroprusside, desensitisation to ATP occurred rapidly and without any change in the inhibitory electrical or mechanical responses to field stimulation. The ijp and relaxation in the BRP were insensitive to apamin but abolished by oxyhaemoglobin (4-8 x 10-6M), as were the responses to extract and sodium nitroprusside. In TEA (10-2M), field stimulation evoked relaxations with no accompanying electrical change. The ijp may be unconnected with or additional to another mechanism producing relaxation. The relationship between membrane potential and ijp in the BRP was non-linear. Ijp amplitude was initially increased during membrane potential displacement from -45mV to approximately -60mV. Thereafter (-60 to -l03mV) the ijp was reduced. Ijps were abolished at -27 and -103mV; reversal was not observed. The hyperpolarisation to extract was also enhanced during passive displacement of the membrane potential to more negative values (-57mV). Membrane resistance increased during the ijp. The extract produced inconsistent changes in membrane resistance, possibly because of the presence of more than one active component. K+ withdrawal failed to enhance the ijp or hyperpolarisation to extract and 20mM K+ did not abolish the the ijp at membrane potentials exceeding EK (-49mV). Thus, the ijp or hyperpolarisation to extract are unlikely to be mediated by an increased K+ conductance. Reducing the Cl- abolished the hyperpolarisation to field stimulation and extract. This occurred more quickly than the anticipated reduction in the Cl- gradient and may be due to Ca2+ chelation by the anion substitute (glutamate or benzenesulphonate) or blockade of the resting conductance which is normally inactivated by the transmitter. Ouabain (1-5x 10-5M), which reduces both the Na+ and Cl- gradients, abolished the ijp, implicating either of these ions as the ionic species involved. In the rat and rabbit anococcygeus, field stimulation and extract each reduced guanethidine-induced tone. This was unaccompanied in the majority of cells in the rat by any significant electrical response. In the remaining cells, inhibition of the membrane potential oscillations occurred. The rabbit anococcygeus differed in that inhibition of the electrical oscillations was observed in every cell exhibiting this behaviour. However, the majority of cells in the rabbit were electrically quiescent and showed only small hyperpolarisations to field stimulation and no electrical response to extract. Apamin (1 x 10-7M) failed to block the electrical and mechanical response to field stimulation in the rabbit but did inhibit transiently that to extract. The latter effect may be due to the initial excitatory effects of apamin. The similarities between the electrical effects of the extract and those of inhibitory nerve stimulation in the BRP, rat and rabbit anococcygeus muscles are generally consistent with their being mediated by the same active component. Moreover, the ijp in the BRP shows properties which have not been reported in other non-adrenergic noncholinergically innervated smooth muscles.

El perfil del educador para el siglo XXI

Antes de pensar en una primera aproximación a lo que podría ser el perfil del educador para el siglo XXI, sería conveniente iniciar con algunas reflexiones a manera de marco teórico sobre la concepción del hombre y de la educación que queremos para la construcción de un futuro posible y deseable. Esta acción podría lograrse si empezamos desde ya, pero no como una tarea asignada s610 al educador, sino como una responsabilidad compartida entre todos, en donde por ejemplo, la familia pueda rescatar su papel de ser el primer agente educativo, contando desde luego con la colaboración y compromiso de la misma sociedad y para que ésta reasuma su papel de educadora, a través del uso racional y objetivo de los medios masivos de comunicación, cine, radio, T.V., T.V. cable, computadores, y prensa hablada y escrita.

Desenvolvimento de uma bancada para a realização de ensaios de auto-amortecimento em cabos condutores de energia elétrica

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2015.

Consumo de pornografía por las y los adolescentes del colegio Manuel J. Calle de la ciudad de Cuenca, 2008

Con un diseño cuantitativo cualitativo se incluyó una población de estudio de 961 alumnos y alumnas asistentes y matriculados en el año lectivo 2008-2009 de los cuales se excluyeron 48. Después de cinco reuniones de trabajo se recopiló la información cuantitativa por medio de un formulario de entrevista autoaplicado y complementado con una discusión de grupo focal de 5 participantes para ser analizada cualitativamente. Resultados: el 66,7% (n = 617) de los participantes fueron varones y el 33,3% (n = 296) mujeres. El 74,7% de los encuestados estuvo entre 10 y 16 años. El 78,7% de la población de estudio tenía conocimientos previos sobre material pornográfico y lo había utilizado. De ellos los varones fueron el 79,6%. Las razones que les llevaron a conocer la pornografía fueron: curiosidad (46,3%), los amigos (44,8%) y los familiares (6,8%). Para el 59,8% de los entrevistados resulta fácil conseguir material pornográfico. Las películas en CD y DVD (67,4%) y las páginas de Internet (31,2%) son los principales medios. Las revistas y la televisión por cable permiten un 27,8% del acceso. El 60.7% de los entrevistados señaló que la finalidad de uso de este material era obtener información más real sobre la sexualidad. Un 21,6% justificó el uso como opción para aprender nuevas técnicas y los restantes señalaron que mejoraban la satisfacción sexual, las fantasías o mejoraban la relación con la pareja. Sobre el significado de ver pornografía el 50,1% la calificó de imprudente y uno de cada tres estudiantes la consideró desagradable (38,4%), agradable (38%) nocivo (36,7%) y hasta beneficioso (21,1%). Los factores asociados al consumo de material pornográfico fueron los CDs, DVDs, revistas y TV por cable, no solamente como medios sino como material de muy fácil acceso. El análisis del grupo focal mostró algunas censuras, de parte de las mujeres, para el consumo de pornografía y de su presencia sin control en el escenario estudiantil del adolescente. Calificaron como negocio ilícito e inmoral de repercusiones reprochables e impredescibles. Discusión: e consumo de pornografía, sin perjuicio de la utilidad que pueda generar, es más una problemática social que debe enfrentársele. Para orientar la actuación de los adolescentes se requiere la participación activa de la sociedad civil, a efecto de lograr aminorar el impacto que genera este tipo de conductas sin control

The Cameraman

In this novel segment titled The Cameraman, a fictionalized version of silent film icon Buster Keaton grapples with his newfound role at big picture studio MGM, which has stripped him of his creative influence. For the first time in his career, Buster must operate with little authority in what was the beginning of the Hollywood studio system. This excerpt’s narrative present takes place in New York City in 1928 during the filming of The Cameraman, with flashbacks to Los Angeles in 1927, prior to the filming. The close third-person narrator examines what it means for Buster to be famous, to be an artist, and what happens when public and private identities are conflated.

Comunicación multimaestro a través de par trenzados RS-485 (HALF-DUPLEX)

En este proyecto se ha desarrollado un protocolo para establecer una comunicación multimaestro entre distintos dispositivos sobre una red de cable de par trenzado rs-485 de tipo half-duplex. Se explican los modos de envío half-duplex y full-duplex y los modelos de comunicación multimaestro y maestro-esclavo para establecer diferencias y se justifica la implementación de este protocolo. Se ha realizado un estudio y análisis del protocolo a implementar y se describen las decisiones de diseño empleadas para resolver los distintos problemas encontrados a la hora de analizar la capacidad de la red. Luego se ofrece una implementación del protocolo en lenguaje C/C++ para la plataforma Arduino y se explican los distintos casos de uso que se pueden dar por dispositivo. En este documento se describe de forma completa y punto por punto el trabajo realizado a lo largo de varios capítulos en forma de texto e imágenes o representaciones que dan al lector distintas vías para entender lo que aquí se explica.