909 resultados para passive voice


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The ability to hear a target signal over background noise is an important aspect of efficient hearing in everyday situations. This mechanism depends on binaural hearing whenever there are differences in the inter-aural timing of inputs from the noise and the signal. Impairments in binaural hearing may underlie some auditory processing disorders, for example temporal-lobe epilepsies. The binaural masking level difference (BMLD) measures the advantage in detecting a tone whose inter-aural phase differs from that of the masking noise. BMLD’s are typically estimated psychophysically, but this is challenging in children or those with cognitive impairments. The aim of this doctorate is to design a passive measure of BMLD using magnetoencephalography (MEG) and test this in adults, children and patients with different types of epilepsy. The stimulus consists of Gaussian background noise with 500-Hz tones presented binaurally either in-phase or 180° out-of-phase between the ears. Source modelling provides the N1m amplitude for the in-phase and out-of-phase tones, representing the extent of signal perception over background noise. The passive BMLD stimulus is successfully used as a measure of binaural hearing capabilities in participants who would otherwise be unable to undertake a psychophysical task.

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The poor retention and efficacy of instilled drops as a means of delivering drugs to the ophthalmic environment is well-recognised. The potential value of contact lenses as a means of ophthalmic drug delivery, and consequent improvement of pre-corneal retention is one obvious route to the development of a more effective ocular delivery system. Furthermore, the increasing availability and clinical use of daily disposable contact lenses provides the platform for the development of viable single-day use drug delivery devices based on existing materials and lenses. In order to provide a basis for the effective design of such devices, a systematic understanding of the factors affecting the interaction of individual drugs with the lens matrix is required. Because a large number of potential structural variables are involved, it is necessary to achieve some rationalisation of the parameters and physicochemical properties (such as molecular weight, charge, partition coefficients) that influence drug interactions. Ophthalmic dyes and structurally related compounds based on the same core structure were used to investigate these various factors and the way in which they can be used in concert to design effective release systems for structurally different drugs. Initial studies of passive diffusional release form a necessary precursor to the investigation of the features of the ocular environment that over-ride this simple behaviour. Commercially available contact lenses of differing structural classifications were used to study factors affecting the uptake of the surrogate actives and their release under 'passive' conditions. The interaction between active and lens material shows considerable and complex structure dependence, which is not simply related to equilibrium water content. The structure of the polymer matrix itself was found to have the dominant controlling influence on active uptake; hydrophobic interaction with the ophthalmic dye playing a major role. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

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The popular technologies Wi-Fi and WiMAX for realization of WLAN and WMAN respectively are much different, but they could compliment each other providing competitive wireless access for voice traffic. The article develops the idea of WLAN/WMAN (Wi-Fi/WiMAX) integration. WiMAX is offering a backup for the traffic overflowing from Wi-Fi cells located into the WiMAX cell. Overflow process is improved by proposed rearrangement control algorithm applied to the Wi-Fi voice calls. There are also proposed analytical models for system throughput evaluation and verification of the effectiveness using WMAN as a backup for WLAN overflow traffic and the proposed call rearrangement algorithm as well.

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Progress on advanced active and passive photonic components that are required for high-speed optical communications over hollow-core photonic bandgap fiber at wavelengths around 2 μm is described in this paper. Single-frequency lasers capable of operating at 10 Gb/s and covering a wide spectral range are realized. A comparison is made between waveguide and surface normal photodiodes with the latter showing good sensitivity up to 15 Gb/s. Passive waveguides, 90° optical hybrids, and arrayed waveguide grating with 100-GHz channel spacing are demonstrated on a large spot-size waveguide platform. Finally, a strong electro-optic effect using the quantum confined Stark effect in strain-balanced multiple quantum wells is demonstrated and used in a Mach-Zehnder modulator capable of operating at 10 Gb/s.

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Long reach-passive optical networks (LR-PON) are being proposed as a means of enabling ubiquitous fiber-to-the-home (FTTH) by massive sharing of network resources and therefore reducing per customer costs to affordable levels. In this paper, we analyze the chain solutions for LR-PON deployment in urban and rural areas at 100-Gb/s point-to-point transmission using dual polarization-quaternary phase shift-keying (DP-QPSK) modulation. The numerical analysis shows that with appropriate finite impulse response (FIR) filter designs, 100-Gb/s transmission can be achieved with at least 512 way split and up to 160 km total distance, which is sufficient for many of the optical paths in a practical situation, for point-to-point link from one LR-PON to another LR-PON through the optical switch at the metro nodes and across a core light path through the core network without regeneration.

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Passively mode locked fibre lasers have a variety of applications ranging from telecommunication to medical photonics. Carbon nanotubes (CNTs) have attracted recently a great deal of attention as a promising solution for saturable absorber elements required for laser mode locking (see e.g. [1-3] and references therein). CNTs can be used as a saturable absorber in passively mode locked fibre laser directly [1,2] or as a CNTs polymer composites [3]. An attractive feature of CNT-based solutions in fibre lasers is a possibility to maintain the compactness, robustness of all-fibre format and low cost through using all standard telecom compatible components. The two important technical challenges in such type of lasers are: (i) to achieve stable polarization properties of the generated radiation without using complex control elements, and, (ii) to avoid low frequency instabilities of the mode-locked pulse train. In this paper we report results of the experiments on mode-locked soliton fibre laser using the following standard components: 1m of highly doped erbium fibre (Liekki Er80-8/125) serves as the gain medium with nominal absorption of 80 dB/m at 1530 nm; a 976 nm laser diode providing up to 310mW power is used to pump the laser via a 980/1550 wavelength division multiplexing; an isolator is employed to ensure single direction oscillation; SMF-28 is used to create necessary amount of anomalous dispersion to form soliton pulse making the total cavity length around 7.83 m; the CNT-polyvinyl alcohol polymer saturable absorber sandwiched in the FC/PC connector is used as a mode-locker device (see [3] for details). © 2011 IEEE.

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Extensive numerical investigations are undertaken to analyze and compare, for the first time, the performance, techno-economy, and power consumption of three-level electrical Duobinary, optical Duobinary, and PAM-4 modulation formats as candidates for high-speed next-generation PONs supporting downstream 40 Gb/s per wavelength signal transmission over standard SMFs in C-band. Optimization of transceiver bandwidths are undertaken to show the feasibility of utilizing low-cost and band-limited components to support next-generation PON transmissions. The effect of electro-absorption modulator chirp is examined for electrical Duobinary and PAM-4. Electrical Duobinary and optical Duobinary are powerefficient schemes for smaller transmission distances of 10 km SMFs and optical Duobinary offers the best receiver sensitivity albeit with a relatively high transceiver cost. PAM-4 shows the best power budget and costefficiency for larger distances of around 20 km, although it consumes more power. Electrical Duobinary shows the best trade-off between performance, cost and power dissipation.

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We demonstrate a Q-switched Raman fiber laser using molybdenum disulfide (MoS2) as a saturable absorber (SA). The SA is assembled by depositing a mechanically exfoliated MoS2 onto a fiber ferrule facet before it is matched with another clean ferrule via a connector. It is inserted in a Raman fiber laser cavity with a total cavity length of about 8km to generate a Q-switching pulse train operating at 1560.2 nm. A 7.7-km-long dispersion compensating fiber with 584 ps·nm?1km?1 of dispersion is used as a nonlinear gain medium. As the pump power is increased from 395mW to 422mW, the repetition rate of the Q-switching pulses can be increased from 132.7 to 137.4 kHz while the pulse width is concurrently decreased from 3.35μs to 3.03 μs. The maximum pulse energy of 54.3 nJ is obtained at the maximum pump power of 422mW. These results show that the mechanically exfoliated MoS2 SA has a great potential to be used for pulse generation in Raman fiber laser systems.

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A dolgozat a politikatudomány és közgazdaság-tudomány határán álló kivonulás-tiltakozás-hűség modell lényegét járja körbe. Az Albert O. Hirschman által felépített gondolati keret szemléleti frissessége és sajátos megközelítési módja rendkívül termékenyítően hatott az elmúlt évtizedekben a társadalomtudományok fejlődésére. Mégis viszonylag periferikus helyet foglal el a közgazdaság-tudományon belül, miközben például a rendszerváltás és az azt követő társadalmi feszültségek megjelenése szempontjából is sokoldalúan használható fogalmi keretről van szó. A válság indukálta turbulens környezet még inkább rávilágít arra, hogy ma is időszerű perspektívát kínál a hanyatlás politikai gazdaságtana, azaz hasznos elemzési kapaszkodó nyújt az úgynevezett Hirschman-trilemma a társadalmi és gazdasági folyamatok értelmezéséhez. ________ The article concerns the "exit, voice, and loyalty" concept, which straddles the border of political science and economics. This theoretical framework, invented by Albert O. Hirschman, has exercised a fruitful influence in the social sciences in the last few decades, through its fresh features and original approach. However, it holds a peripheral position in economics and plays an undervalued role in eco-nomic education in Hungary, even though it can be flexibly applied in analyses of such phenomena as the economic transition and the ensuing social tensions. Moreover the very turbulence of the conditions brought about by the crisis show that the political economy of decline offers a relevant perspective, so that the Hirschman trilemma is a practical analytical tool for understanding social and economic processes.

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Tanulmányunkban az Albert 0. Hirschman által kialakított „kivonulás, tiltakozás, hűség” koncepció metaelméleti felhasználásával a „kapitalizmus változatai” elméletet vesszük bírálat alá. Egyrészt arra mutatunk rá, hogy már a különböző piacgazdasági modellek tipologizálásához használt vállalatelméleti dimenziójú elemzések is építkeznek a Hirschman-trilemmából, másrészt arra hívjuk fel a figyelmet, hogy olyan sajátos eszközről van szó, amely a tőke- és munkaerő-piaci folyamatok elemzésére támaszkodva új perspektívát is kínál a kapitalista gazdaságok komparatív vizsgálatához. A dolgozat terjedelmi okokból az empirikus kutatásokat megalapozó elméleti alapozásra szorítkozik. ____ In our study we deal with the critical analysis of the “varieties of capitalism” theory by using the “exit, voice, and loyalty” meta-theory invented by Albert O. Hirschman. The paper emphasizes that on the one hand the analyses of the theory of the firm and business used for the classification of distinct market models are also building upon the “Hirschman trilemma”, and on the other hand, it draws attention to the fact that the Hirschmanian method based on labor market and capital market offers a new perspective for the comparative analysis of capitalist economies. The focus of the article is only the theoretical foundation of empirical studies as a result of limitation of scope.

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This dissertation analyzes various types of non-canonical texts authorized by women from a wide spectrum of classes and races in the Spanish colonies. The female voice, generally absent from official colonial documents of the sixteenth, seventeenth and eighteen centuries, left a gap in the complex subject of women's history and social participation. Through the study of personal letters, autobiographies, journals, court documents, inquisitorial transcripts, wills and testaments, edicts, orders, proclamations and posters, that voice is recovered. Thus, the Indigenous, Spaniards and African women and their descendants who lived during this period left their written legacy and proof of participation. Beginning with a thorough history of the native woman's interest in writing, this study focuses on how women of all social levels utilized the few means of writing available at their disposal to display a testimonial, critical and sometimes fictional narrative of their surroundings. ^ This investigation concludes that it is necessary to change the traditional image of the passive women of the colonies, subjected to a patriarchal authority and unable to speak or grow on their own. The documents under study, introduced women who were able to self represent themselves as followers of the tradition while at the same time their writings were denying that very same statement. They passed from the private arena to the public one with discourses that confessed their innermost feelings and concerns, challenged the authority of the Inquisitor or the Governor, exposed their sexual freedom and transvestite narratives, successfully developed stratagems that challenged the official ideology of the oppressive religious environment and established their own authority reaching at last the freedom of their souls. ^

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Republican John Sherman, United States Congressman, Senator, Treasury Secretary, and Secretary of State had a political career of major importance from 1855 to 1898, yet there have been only casual references by historians and only two biographies of him, with the most recent published in 1902. From a strong Whig Party background, he was first elected to the United States House of Representatives in 1854; switching to the Republicans that same year. Then elevated to the Senate in 1861, he served in that body throughout the Civil War and Reconstruction when he was the most important voice of party unity and moderation. In 1877, the new President Rutherford Hayes appointed Sherman Secretary of the Treasury. He returned to the Senate after the Hayes administration where he sat for the following 15 years. In this particularly notable period, he not only led the upper house, but he engineered more bills in Congress which bore his name than any other member of either house. These included the critically important Sherman Silver Purchase Act, the Sherman Anti-Trust Act and Sherman Inter-State Commerce Act. In 1897 he left the Senate finally when William McKinley appointed him Secretary of State. ^ Through this long, distinguished career, Sherman was involved in all the important legislation that brought the country through the Civil War and Reconstruction and into the post-war world of the Gilded Age of rapid industrialization, and urban growth, Politically, he never strayed far from the nationalistic and economic principles of the Whig Party, and brought both these values to bear in the Republican Party that dominated American political life from 1860 to 1900. Similarly, party loyalty and loyalty to the President always characterized his service. He was indeed, an exemplar of political and statesmanship. ^ While research for this dissertation included review of both journal and monographic literature, its basis lies more critically in primary research in unpublished archival material in repositories from Maine to Ohio, in particular the Library of Congress. ^

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Voice communication systems such as Voice-over IP (VoIP), Public Switched Telephone Networks, and Mobile Telephone Networks, are an integral means of human tele-interaction. These systems pose distinctive challenges due to their unique characteristics such as low volume, burstiness and stringent delay/loss requirements across heterogeneous underlying network technologies. Effective quality evaluation methodologies are important for system development and refinement, particularly by adopting user feedback based measurement. Presently, most of the evaluation models are system-centric (Quality of Service or QoS-based), which questioned us to explore a user-centric (Quality of Experience or QoE-based) approach as a step towards the human-centric paradigm of system design. We research an affect-based QoE evaluation framework which attempts to capture users' perception while they are engaged in voice communication. Our modular approach consists of feature extraction from multiple information sources including various affective cues and different classification procedures such as Support Vector Machines (SVM) and k-Nearest Neighbor (kNN). The experimental study is illustrated in depth with detailed analysis of results. The evidences collected provide the potential feasibility of our approach for QoE evaluation and suggest the consideration of human affective attributes in modeling user experience.

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This flyer promotes the event "One Voice, Two Attitudes: Perceptions of Spanish and English among Cuban Americans in Miami Lecture by Phillip M. Carter" hosted by the Cuban Research Institute.