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991.
This paper addresses a classical but important problem: The coupling of lexical tones and sentence intonation in tonal languages, such as Chinese, focusing particularly on voice fundamental frequency (F1) contours of speech. It is important because it forms the basis of speech synthesis technology and prosody analysis. We provide a solution to the problem with a constrained tone transformation technique based on structural modeling of the F1 contours. This consists of transforming target values in pairs from norms to variants. These targets are intended to sparsely specify the prosodic contributions to the F1 contours, while the alignment of target pairs between norms and variants is based on underlying lexical tone structures. When the norms take the citation forms of lexical tones, the technique makes it possible to separate sentence intonation from observed F0 contours. When the norms take normative F0 contours, it is possible to measure intonation variations from the norms to the variants, both having identical lexical tone structures. This paper explains the underlying scientific and linguistic principles and presents an algorithm that was implemented on computers. The method's capability of separating and combining tone and intonation is evaluated through analysis and re-synthesis of several hundred observed F0 contours. 相似文献
992.
Electrochemistry of marmatite-carbon paste electrode in the presence of bacterial strains 总被引:1,自引:0,他引:1
The electrochemical behaviors of a marmatite-carbon paste electrode with the chemical leaching of Fe3+ ions, or the microbial leaching using Acidithiobacillus ferrooxidans, were compared. The cyclic voltammograms of the electrode in the presence and absence of bacterial strains showed that the leaching process of marmatite was carried out by the different reactions occurring in the interface of the marmatite electrode-leach liquid. The polarization currents of the electrode under the differently applied potentials suggested that the microbial leaching of marmatite could be accelerated by the applied potential. The SEM observations indicated that the corrosion pits formed in the electrode surface were similar to the attached bacterial cells in shape and size, other than that by the chemical leaching of Fe3+ ions. The contact leaching of the attached cells on the mineral substrate played an important role on the dissolution of marmatite in addition to the chemical leaching of Fe3+ ions. 相似文献
993.
Ulrich A Adonin A Jacoby J Turtikov V Fernengel D Fertman A Golubev A Hoffmann DH Hug A Krücken R Kulish M Menzel J Morozov A Ni P Nikolaev DN Shilkin NS Ternovoi VY Udrea S Varentsov D Wieser J 《Physical review letters》2006,97(15):153901
High-energy heavy ions are an ideal tool to generate homogeneously excited, extended volumes of nonthermal plasmas. Here, the high-energy loss (dE/dx) and absolute power deposition of heavy ions interacting with matter has been used to pump an ultraviolet laser. A pulsed 70 MeV/u 238U beam with up to 2.5 x 10(9) particles in approximately 100 ns beam bunches was stopped in a 1.2 m long laser cell filled with a 1.6 bar Ar-Kr-F2 mixture (typically 50%:49.9%:0.1%). Laser effect on the 248 nm KrF* excimer transition is clearly demonstrated. 相似文献
994.
Daim-Yuang Sun Sheng-Chung Ni Tzu-Chen Huang 《Applied mathematics and computation》2010,216(11):3343-3354
In this study, a modified line-up competition algorithm (LCA) is used to solve parameter selection problems. The so-called parameter selection problems contain parameter identification problems and optimal control problems. Once the later problems are transformed by control parametrization, the parameters embedded in both problems are selected by the proposed method under the framework of integration approach. Two parameter identification problems and one optimal control problem are given to demonstrate the use of LCA. The results show that in addition to being insensitive to the initial conditions, LCA is very efficient in solving highly nonlinear parameter selection problems. 相似文献
995.
The current paper is mainly concerned with the internal layers for a quasi--linear singularly perturbed differential equation with time delays. By using the method of boundary layer functions and the theory of contrast structures, the existence of a uniformly valid smooth solution is proved, and the asymptotic expansion is constructed. As an application, a concrete example is presented to demonstrate the effectiveness of our result. 相似文献
996.
An inequality model for solving interval dynamic response of structures with uncertain-but-bounded parameters 总被引:1,自引:0,他引:1
In this paper, we look into the dynamic response of structures with uncertain-but-bounded parameters. A new inequality model for determining the interval dynamic response is presented. First we propose an interval dynamic response solution theorem. An inequality model which is a mathematics programming problem is suggested by the presented theorem. Using the central difference method, we substitute the differential items of the inequality model by difference items. By solving them, the interval dynamic response can be obtained. Two examples are used to illustrate the feasibility and the efficiency of the model. 相似文献
997.
Yanjiang Han Duanzhi Yin Mingqiang Zheng Wei Zhou ZhenHong Lee Lan Zhan Yufei Ma Mingxing Wu Lingli Shi Ni Wang Jianbo Lee Cheng Wang Zheng Lee Yongxian Wang 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(2):279-286
The aim of this study was to develop a radiopharmaceutical for the imaging of CXCR4-expressing tumors in vivo. For 125I-labeling, 125I-SIB was synthesized and conjugated with the ε-NH2 group of Ac-TZ14011, a specific CXCR4 antagonist. The specific radioactivity of the product was 5 GBq/μmol and the radiochemical purity (RCP) was 96% (n = 3). After 6 h, the RCP of the product in PBS was 93%. The MCF-7 cell uptake of Ac-TZ14011 was rapid and high. Primary biodistribution studies indicated that 125I-IB-Ac-TZ14011 was mainly excreted via the kidney, and further evaluation in mice with induced tumors was necessary. 相似文献
998.
The direct electrocatalytic oxidation of glucose in alkaline medium at an electrode modified with microcubes of porous cuprous oxide is reported. Compared to the glassy carbon electrode, a substantial increase in the efficiency of the electrocatalytic oxidation of glucose is observed starting at around +0.20 V (vs. Ag/AgCl). The pH dependence of the response was examined by cyclic voltammetry. This non-enzymatic amperometric sensor may be used for non-enzymatic detection of glucose with a high and reproducible sensitivity of 10.95 μA per mM at a potential of +0.40 V, with response times of <3 s, a linear range from 2.0 to 350 μM, and a detection limit of 1.3 μM. The porous microcubes are conveniently prepared, and display high sensitivity and repeatability. 相似文献
999.
Herein a water-soluble ‘click’ modified coumarin-based fluorescent probe for hydrogen peroxide is reported. This probe shows significant intensity increases (up to fivefold) in near-green fluorescence upon reaction with hydrogen peroxide, and good selectivity over other reactive oxygen species. 相似文献
1000.
This work aimed to classify the categories (produced by different processes) and brands (obtained from different geographical origins) of Chinese soy sauces. Nine variables of physico-chemical properties (density, pH, dry matter, ashes, electric conductivity, amino nitrogen, salt, viscosity and total acidity) of 53 soy sauce samples were measured. The measured data was submitted to such pattern recognition as cluster analysis (CA), principal component analysis (PCA), discrimination partial least squares (DPLS), linear discrimination analysis (LDA) and K-nearest neighbor (KNN) to evaluate the data patterns and the possibility of differentiating Chinese soy sauces between different categories and brands. Two clusters corresponding to the two categories were obtained, and each cluster was divided into three subsets corresponding to three brands by the CA method. The variables for LDA and KNN were selected by the Fisher F-ratio approach. The prediction ability of all classifiers was evaluated by cross-validation. For the three supervised discrimination analyses, LDA and KNN gave 100% predications according to the sample category and brand. 相似文献