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1.
JM Olivares Diez 《Canadian Metallurgical Quarterly》1995,41(2):148-161
During the last decades, the term "anhedonia", conceptualized as a incapacity to experience pleasure, have become associated with conditions as different as schizophrenia and depression. This paper deals with the conceptual and historial frames in which anhedonia was first constructed, and shows that the sources for the current fuzziness of this concept include neglect of the fact that anhedonia is conceptually parasitical upon the notion of pleasure, that it has been rather superficially conceptualized as the reduction or abolition in a "putative" function which itself is unlikely to be unitary in nature, and that it has never been quite specified whether the mechanism concerns a deficit in brain signal or not. 相似文献
2.
Franquelo L.G. Prats Ma.A.M. Portillo R.C. Galvan J.I.L. Perales M.A. Carrasco J.M. Diez E.G. Jimenez J.L.M. 《Industrial Electronics, IEEE Transactions on》2006,53(2):458-466
In this paper, a novel three-dimensional (3-D) space-vector algorithm for four-leg multilevel converters is presented. It can be applied to active power filters or neutral-current compensator applications for mitigating harmonics and zero-sequence components using abc coordinates (referred from now on this paper as natural coordinates). This technique greatly simplifies the selection of the 3-D region where a given voltage vector is supposed to be found. Compared to a three-level modulation algorithm for three-leg multilevel converters, this algorithm does not increase its complexity and the calculations of the active vectors with the corresponding switching time that generate the reference voltage vector. In addition, the low-computational cost of the proposed algorithm is always the same and it is independent of the number of levels of the converter. 相似文献
3.
M. Delgado-Pinar J. Mora A. Diez J.L. Cruz M.V. Andres 《Photonics Technology Letters, IEEE》2005,17(3):552-554
We report a wavelength-switchable fiber ring laser that includes a Bragg grating-based acoustooptic superlattice modulator. Wavelength switching of the laser emission is achieved by controlling the peak reflectivity of the different reflection bands that appear on both sides of the Bragg wavelength when a longitudinal acoustic wave propagates along the grating. 相似文献
4.
Yolk and embryonic total lipids were extracted from spotted dogfish eggs at two developmental stages. Total lipids were fractionated
into neutral lipids (NL) and polar lipids (PL), and the fatty acid composition of each group was determined. Yolk lipid composition
was found to be quantitatively different (NL/PL≊1) from embryo lipid composition (NL/PL≊0.5), for both stages of development.
However, individual fatty acid composition did not differ from younger to older eggs for either yolk or embryo. There were
significant differences (p<0.05) in major fatty acid groups from yolk and embryonic PL for saturated fatty acids, monounsaturated
fatty acids (MUFA) and n−3 polyunsaturated fatty acids (PUFA) for younger eggs, and for MUFA and n−3 PUFA for older eggs.
For NL, only MUFA composition from the oldest eggs showed differences between yolk and embryo. Results are discussed in terms
of embryonic needs for highly unsaturated fatty acid (HUFA) biosynthesis, as well as to provide some explanations for the
unusually high levels of 20∶4n−6 in both yolk and embryonic neutral lipids and polar lipids. 相似文献
5.
In the near future, several radio access technologies will coexist in Beyond 3G mobile networks (B3G), and they will be eventually transformed into one seamless global communication infrastructure. Self-managing systems (i.e., those that self-configure, self-protect, self-heal, and self-optimize) are the solution to tackle the high complexity inherent to these networks. In this context, this paper proposes a system for autodiagnosis in the Radio Access Network (RAN) of wireless systems. The malfunction of the RAN may be due not only to a hardware fault but also (and more difficult to identify) to a bad configuration. The proposed system is based on the analysis of Key Performance Indicators (KPIs) in order to isolate the cause of the network malfunction. In this paper, two alternative probabilistic systems are compared, which differ on how KPIs are modeled (continuous or discrete variables). Experimental results are examined in order to support the theoretical concepts, based on data from a live network. The drawbacks and benefits of both systems are studied, and some conclusions on the scenarios under which each model should be used are presented. 相似文献
6.
Toptchiyski G. Kindt S. Petermann K. Hilliger E. Diez S. Weber H.G. 《Lightwave Technology, Journal of》1999,17(12):2577-2583
An advanced time-domain dynamical model for the investigation of semiconductor optical amplifiers (SOA) is presented. The model accounts for the ultrafast gain dynamics, the gain saturation and the gain spectral profile. It is also suitable for analyzing the amplifier in a system environment. As an example the model is used to investigate the gain dynamics of an SOA as well as the characteristics of an interferometer switch semiconductor laser amplifier in a loop mirror (SLALOM). Good agreement between modeling and experiment is shown. The model can be applied to the investigation of other optically time-division multiplexed (OTDM) applications, too 相似文献
7.
Maria Martinez‐Ibaez Eduardo Sanchez‐Diez Lixin Qiao Yan Zhang Xabier Judez Alexander Santiago Itziar Aldalur Javier Carrasco Haijin Zhu Maria Forsyth Michel Armand Heng Zhang 《Advanced functional materials》2020,30(16)
Solid‐state lithium metal (Li°) batteries (SSLMBs) are believed to be the most promising technologies to tackle the safety concerns and the insufficient energy density encountered in conventional Li‐ion batteries. Solid polymer electrolytes (SPEs) inherently own good processability and flexibility, enabling large‐scale preparation of SSLMBs. To minimize the growth of Li° dendrites and cell polarization in SPE‐based SSLMBs, an additive‐containing single Li‐ion conductive SPE is reported. The characterization results show that a small dose of electrolyte additive (2 wt%) substantially increases the ionic conductivity of single Li‐ion conductive SPEs as well as the interfacial compatibility between electrode and SPE, allowing the cycling of SPE‐based cells with good electrochemical performance. This work may provide a paradigm shift on the design of highly cationic conductive electrolytes, which are essential for developing safe and high‐performance rechargeable batteries. 相似文献
8.
Ca3Co4?xMnxOy polycrystalline thermoelectric ceramics with small amounts of Mn have been prepared by the classical solid state method. X-ray diffraction data have shown that Ca3Co4O9 is the major phase, with small amounts of the Ca3Co2O6 one. Moreover, they show that the Mn has been incorporated into these two phases. Electrical resistivity decreases, compared with the values for undoped samples, with Mn content until a minimum for the 0·03 doped ones, increasing for higher Mn substitution. Seebeck coefficient does not change in all the measured temperature range, independently of Mn content. The improvement in electrical resistivity leads ~30% higher power factor values for the 0·03 Mn doped samples than that obtained in the undoped ones. The maximum power factor at 800°C, ~0·28 mW K?2 m?1, is close to that obtained in much higher density samples, clearly indicating the good thermoelectric properties of these samples. 相似文献
9.
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