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A 4:1 SERDES IC suitable for SONET OC-192 and 10-Gb/s Ethernet is presented. The receiver, which consists of a limiting amplifier, a clock and data recovery unit, and a demultiplexer, locks automatically to all data rates in the range 9.95-10.7 Gb/s. At a bit error rate of less than 10/sup -12/, it has a sensitivity of 20 mV. The transmitter comprises a clock multiplying unit and a multiplexer. The jitter of the transmitted data signal is 0.2 ps RMS. This is facilitated by a novel notched inductor layout and a special power supply concept, which reduces cross-coupling between the transmitter and receiver. Integrated in a 0.13-/spl mu/m CMOS technology, the total power consumption from both 1.2- and 2.5-V supplies is less than 1 W.  相似文献   
2.
High-frequency functors are arguably among the earliest perceived word forms and may assist extraction of initial vocabulary items. Canadian 11- and 8-month-olds were familiarized to pseudo-nouns following either a high-frequency functor the or a low-frequency functor her versus phonetically similar mispronunciations of each, kuh and ler, and then tested for recognition of the pseudo-nouns. A preceding the (but not kuh, her, ler) facilitated extraction of the pseudo-nouns for 11-month-olds; the is thus well-specified in form for these infants. However, both the and kuh (but not her-ler) facilitated segmentation for 8-month-olds, suggesting an initial underspecified representation of high-frequency functors.  相似文献   
3.
This note reconsiders the nonnegative integer-valued bilinear processes introduced by Doukhan et al. [Doukhan, P., Latour, A., Oraichi, D., 2006. A simple integer-valued bilinear time series model. Adv. Appl. Prob. 38, 559–578]. Using a hidden Markov argument, we extend their result of the existence of a stationary solution for the INBL(1, 0, 1, 1) process to the class of superdiagonal models. Our approach also yields improved parameter restrictions for several moment conditions compared to the ones in [Doukhan, P., Latour, A., Oraichi, D., 2006. A simple integer-valued bilinear time series model. Adv. Appl. Prob. 38, 559–578].  相似文献   
4.
Fifteen new photochromic hybrid materials were synthesized by gas phase loading of fluorinated azobenzenes, namely ortho-tetrafluoroazobenzene (tF-AZB), 4H,4H′-octafluoroazobenzene (oF-AZB), and perfluoroazobenzene (pF-AZB), into the pores of the well-known metal-organic frameworks MOF-5, MIL-53(Al), MIL-53(Ga), MIL-68(Ga), and MIL-68(In). Their composition was analysed by elemental (CHNS) and DSC/TGA. For pF-AZB0.34@MIL-53(Al), a structural model based on high-resolution synchrotron powder diffraction data was developed and the host-guest and guest-guest interactions were elucidated from this model. These interactions of O−H⋅⋅⋅F and π⋅⋅⋅π type were confirmed by significant shifts of the O−H frequencies in loaded and unloaded MOFs of the MIL-53 and MIL-68 series. Most remarkably, all of the synthesized F-AZB@MOF systems can be switched with visible light, and some of them show almost quantitative (>95 %) photo-isomerization between its E and Z forms with no significant fatigue after repeated switching cycles.  相似文献   
5.
It is an empirical fact that the (empirically) relevant models for asset prices often describe markets that are incomplete in terms of their underlying assets, yielding many possible equivalent martingale measures under the no-arbitrage assumption. By using actual derivative prices, i.e., prices as observed in the market, additional information about the empirically relevant equivalent martingale measures might be obtained. In order to be able to process such information easily one needs a convenient way to represent all possible equivalent martingale measures in relation to derivative prices. In this paper we present such a convenient characterization. Conceptually, our characterization is not different from existing characterizations using, for example, Radon–Nikodym derivatives of martingale measures with respect to objective probabilities, but our characterization offers some advantages. The main advantage is that pricing derivatives is split up into two steps. The first step is solving a related complete markets pricing problem. This is a well-studied problem, so that it can easily be solved generally. In the second step a weighted average of the first step complete markets price must be calculated. Pricing under different equivalent martingale measures in the original market only differs with respect to the second step. The empirically relevant weighting can be determined by confronting the theoretical with the actually observed prices. As a byproduct we obtain a new and natural definition of idiosyncratic risk, which we show to be in line with the use of this term in the literature.To illustrate the ideas we discuss several examples. Among others we obtain the Hull–White formula for options on assets with stochastic volatility under close to minimal conditions that (for example) do not rely on a specification of the processes in terms of Itô diffusion.we relax the assumption of no-correlation between asset prices and volatilities in the Hull–White framework; we consider the case where the stochastic volatility does bear a risk-premium; we discuss pricing under stochastic interest rates; and we consider square-root type processes. All these pricing problems, and many more, can conveniently be handled using the approach based on our characterization of the equivalent martingale measures in continuous time markets that are incomplete in the underlying assets.  相似文献   
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7.
Phonemic and phonetic factors in adult cross-language speech perception   总被引:5,自引:0,他引:5  
Previous research has indicated that young infants can discriminate speech sounds across phonetic boundaries regardless of specific relevant experience, and that there is a modification in this ability during ontogeny such that adults often have difficulty discriminating phonetic contrasts which are not used contrastively in their native language. This pattern of findings has often been interpreted as suggesting that humans are endowed with innate auditory sensitivities which enable them to discriminate speech sounds according to universal phonetic boundaries and that there is a decline or loss in this ability after being exposed to a language which contrasts only a subset of those distinctions. The present experiments were designed to determine whether this modification represents a loss of sensorineural response capabilities or whether it shows a shift in attentional focus and/or processing strategies. In experiment 1, adult English-speaking subjects were tested on their ability to discriminate two non-English speech contrasts in a category-change discrimination task after first being predisposed to adopt one of four perceptual sets. In experiments 2, 3, and 4 subjects were tested in an AX (same/different) procedure, and the effects of both limited training and duration of the interstimulus interval were assessed. Results suggest that the previously observed ontogenetic modification in the perception of non-native phonetic contrasts involves a change in processing strategies rather than a sensorineural loss. Adult listeners can discriminate sounds across non-native phonetic categories in some testing conditions, but are not able to use that ability in testing conditions which have demands similar to those required in natural language processing.  相似文献   
8.
This paper is an overview of current understanding in the areas of composites made from biodegradable thermoplastics and wood fillers. The review finds that the composite properties depend on the type of wood filler, the choice of polymer matrix, the wood filler content, the compatibilization technique used and the processing parameters. The extent of interfacial adhesion and the filler morphology are identified as the underlying factors that control the composite properties. Future research needs are identified, including establishment of fundamental relationships between quantified interfacial adhesion and end-use properties and advanced modelling of biodegradation processes.  相似文献   
9.
Japanese infants at the ages of 6, 12, and 18 months were tested on their ability to discriminate three nonsense words with different phonotactic status: canonical keetsu, noncanonical but possible keets, and noncanonical and impossible keet. The results showed that 12 and 18 months olds discriminate the keets/keetsu pair, but infants in all age groups fail to discriminate the keets/keet pair. Taken together with the findings in our previous study [Kajikawa et al., J. Acoust. Soc. Am. 120(4), 2278-2284 (2006)], these results suggest that Japanese infants develop the perceptual sensitivity for native phonotactics after 6 months of age, and that this sensitivity is limited to canonical patterns at this early developmental stage.  相似文献   
10.
This study explored sensitivity to word-level phonotactic patterns in English and Japanese monolingual infants. Infants at the ages of 6, 12, and 18 months were tested on their ability to discriminate between test words using a habituation-switch experimental paradigm. All of the test words, neek, neeks, and neekusu, are phonotactically legitimate for English, whereas the first two words are critically noncanonical in Japanese. The language-specific phonotactical congruence influenced infants' performance in discrimination. English-learning infants could discriminate between neek and neeks at the age of 18 months, but Japanese infants could not. There was a similar developmental pattern for infants of both language groups for discrimination of neek and neeks, but Japanese infants showed a different trajectory from English infants for neekusu/neeks. These differences reflect the different status of these word patterns with respect to the phonotactics of both languages, and reveal early sensitivity to subtle phonotactic and language input patterns in each language.  相似文献   
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