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81.
In this paper, we analyze the effects of several factors and configuration choices encountered during training and model construction when we want to obtain better and more stable adaptation in HMM-based speech synthesis. We then propose a new adaptation algorithm called constrained structural maximum a posteriori linear regression (CSMAPLR) whose derivation is based on the knowledge obtained in this analysis and on the results of comparing several conventional adaptation algorithms. Here, we investigate six major aspects of the speaker adaptation: initial models; the amount of the training data for the initial models; the transform functions, estimation criteria, and sensitivity of several linear regression adaptation algorithms; and combination algorithms. Analyzing the effect of the initial model, we compare speaker-dependent models, gender-independent models, and the simultaneous use of the gender-dependent models to single use of the gender-dependent models. Analyzing the effect of the transform functions, we compare the transform function for only mean vectors with that for mean vectors and covariance matrices. Analyzing the effect of the estimation criteria, we compare the ML criterion with a robust estimation criterion called structural MAP. We evaluate the sensitivity of several thresholds for the piecewise linear regression algorithms and take up methods combining MAP adaptation with the linear regression algorithms. We incorporate these adaptation algorithms into our speech synthesis system and present several subjective and objective evaluation results showing the utility and effectiveness of these algorithms in speaker adaptation for HMM-based speech synthesis.  相似文献   
82.
83.
This paper reports the production of monodisperse water-in-oil (W/O) emulsions using new microchannel emulsification (MCE) devices, asymmetric straight-through MC arrays that were hydrophobically modified. The silicon asymmetric straight-through MC arrays consisted of numerous pairs of microslots and circular microholes whose cross-sectional sizes were 10 μm. This paper primarily focused on investigating the effect of the osmotic pressure of a dispersed phase (Πd) on MCE. This paper also investigated the effects of the type of continuous-phase oils and the dispersed-phase flux (J d) on MCE. The dispersed phases were Milli-Q water and Milli-Q water solutions containing sodium chloride. The continuous phases were decane (as control), hexane, medium chain triacylglyceride (MCT), and refined soybean oil (RSO) solutions containing tetraglycerin monolaurate condensed ricinoleic acid ester (TGCR) as a surfactant. At Πd of exceeding threshold, highly uniform aqueous droplets with coefficients of variation of less than 3% were stably generated via hydrophobic asymmetric straight-through MCs. Monodisperse W/O emulsions with average droplet diameters between 32 and 45 μm were produced using the alkane–oil and triglyceride–oil solutions as the continuous phase. This work also demonstrated that the hydrophobic asymmetric straight-through MC array had remarkable ability to produce highly uniform aqueous droplets at very high J d of up to 1,200 L m−2 h−1.  相似文献   
84.
Suzuki A  Kobayashi S 《Applied optics》1994,33(28):6578-6581
A new design method for a compound parabolic concentrator heat collector is described. The conventional design of the ideal compound parabolic concentrator collector has a touching point between a light absorber and the reflectors. This structure is not preferable from the standpoint of conductive heat leakage and thermal stress on reflector materials. On the other hand, if the absorber and the reflectors are separated from each other, the gap between them usually causes optical errors such as light transmission loss or an increase in the reflection number. We discuss the fact that ideal heat collection is possible, in spite of the gap, by introducing the idea of an effective heat concentration ratio.  相似文献   
85.
OBJECTIVE: For resuscitation of hemorrhagic hypovolemia, we compared the effectiveness of (1) isotonic lactated Ringer's solution (LRS), (2) 2400 mOsm of 7.5% NaCl:6% dextran 70 (HSD), and (3) 2400 mOsm of 7.9% sodium acetate:1.9% NaCl:6% dextran 70 (HAD). DESIGN: In six randomized, blinded experiments for each solution, conscious instrumented adult sheep were hemorrhaged by removing approximately 1.8 L (42 +/- 3 mL/kg) of blood, while maintaining the mean arterial pressure (MAP) at 50 mm Hg for 2 hours. METHODS: Test solutions were infused as needed to restore the cardiac index to baseline. RESULTS: Volume requirements with HAD (236 +/- 29 mL) and HSD (244 +/- 39 mL) were significantly less (p < 0.05) than LRS (3463 +/- 234 mL). Mean arterial pressure was normalized with HSD and LRS, but not with HAD, which resulted in MAPs of 20 to 25 mm Hg less than baseline resulting from a reduced peripheral resistance. Oxygen delivery, however, was significantly higher with HAD during the resuscitation period. Acid-base balance (pH) and oxygen consumption were normalized within 5 minutes of infusion only with HAD. CONCLUSIONS: Small-volume infusion with HAD resulting in "high-flow-low-pressure" resuscitation may offer unique hemodynamic and metabolic advantages for the initial treatment of hemorrhage from trauma.  相似文献   
86.
An intensive chemotherapy combined with surgery, termed "intraoperative local infusion chemotherapy (ILIC)", was devised. The ILIC procedure is to infuse 50 mg of cisplatin through the feeding artery to the tumor, which has been isolated from blood flow by clamping the stomach and blood vessels, before radical surgery. An experiment in dogs showed considerable free Pt transfer into thoracic lymph after ILIC. Sum total Pt in the thoracic lymph after ILIC (294.5 micrograms/3 h) was 4.3 times that after IV administration (68.3 micrograms/3 h). In ILIC, AUC of free Pt in the thoracic lymph was about 5.8 times that in peripheral blood. ILIC was applied in 24 advanced gastric cancer patients, consisting of 6, 2, 4 and 12 in pTNM stage II, IIIA, IIIB and IV, respectively. Pt concentration of the tissues was high in the tumor (23.22 micrograms/g) and the regional lymph nodes (2.95 micrograms/g) compared to that in the serum (0.45 microgram/ml). The survival rate (Kaplan-Meier) in the ILIC patients was significantly higher than that of control patients (matched pair method) from among patients treated by surgery alone. No fatal complications were encountered in any patient treated by ILIC.  相似文献   
87.
Single-mode optical waveguides fabricated from fluorinated polyimides   总被引:9,自引:0,他引:9  
Buried channel optical waveguides were fabricated from fluorinated polyimides. They operated in single mode and showed an optical loss of less than 0.3 and 0.7 dB/cm for TE and TM polarizations, respectively, at a wavelength of 1.3 mum. Moreover, these waveguides had high heat and moisture resistance; the optical loss did not significantly change after heating at 380 degrees C for 1 h or after exposure to 85% relative humidity at 85 degrees C for over 200 h.  相似文献   
88.
The static fracture toughness of a series of eutectic Al-Si casting alloy with different microstructural features has been evaluated. The dominant influence of eutectic silicon in controlling the fracture toughness is thus clarified. The relationship between the fracture toughness and the microstructure was established. Fracture toughness was found to be strongly associated with the size and morphology of silicon particles. The other feature which greatly influences the fracture toughness is the ratio (/DE)Si, i.e. the silicon particle spacing divided by the equivalent particle diameter, rather than the silicon particle spacing, Si. Fracture toughness also correlates well with the void growth parameter, VGP (=y (/DE)Si), proposed by the authors. The results of the present work can be used to develop an understanding of the variation of fracture toughness with the microstructural features of eutectic Al-Si alloys.  相似文献   
89.
Anisotropie properties of the single crystal Pb2Sr2Ho0.5Ca0.5Cu3O8 have been investigated by measuring the electrical resistivity in theab-planeρ ab (H, θ,T), which depends on the angleθ between theab-plane and the magnetic-field direction, in various constant fieldsH perpendicular to the current direction. All the angle-dependent values ofρ ab (H, θ,T) at a constant temperature are scaled to be on one curve as a function of reduced field. The anisotropic parameter γ≡(m c * /m ab * )1/2 is estimated as 12–13, which is larger than that of YBa2Cu3O7 and much smaller than that of Bi2Sr2CaCu2O8. It has been concluded that the anisotropy does not always depend on the thickness of the blocking layer but seems to depend on the overlap of the electronic wave functions along thec-axis. Anisotropy in the pinning potential has also been discussed from the resistive tail in the temperature dependence ofρ ab (H,θ,T).  相似文献   
90.
During cancer invasion, the binding of urokinase-type plasminogen activator (uPA) to its receptor (uPAR) on the surface of a cancer cell is considered a trigger for invasion. Here, we present a stable structure of the solvated complex formed between uPA and uPAR (uPA-uPAR) and investigate the specific interactions between uPA and uPAR by ab initio fragment molecular orbital (FMO) calculations. The result indicates that the electrostatic interactions between the charged amino acid residues existing in both uPA and uPAR make a large contribution to the binding between uPA and uPAR. In particular, Lys23, Lys46, Lys98 and Lys61 of uPA are found to have strong attractive interactions with uPAR. To elucidate the effect of these residues on the interactions between uPA and uPAR, we substituted each of them with the uncharged amino acid Leu and investigated the interactions between the mutated uPA and wild-type uPAR. The interaction energies indicate that Lys46 and Lys98, which bind uPA to the rim of the central ligand-binding cavity of uPAR, make greater contributions to the binding between uPA and uPAR than Lys23, which is positioned at the bottom of the ligand-binding cavity of uPAR. The effect of hydrating water molecules located between uPA and uPAR is also investigated to be significant for the specific interactions between uPA and uPAR. These results are expected to be informative for developing new peptide antagonists that block the binding of uPA to uPAR.  相似文献   
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