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1.
Yanqiu Shao Jiqing Han Ting Liu Yongzhen Zhao 《International Journal of Speech Technology》2007,10(1):45-55
In real speech, not like lexical words (LWs), prosodic words (PWs) are basic rhythmic units. The naturalness of a Text-to-Speech
(TTS) system is directly influenced by the segmentation of the PWs. Most of the PWs are the combination of several LWs. In
this paper, three Lexical Combination Models are proposed to combine LWs into PWs, including a Directed Acyclic Graph Model,
a Segmentation Model and a Markov Model (MM). To cope with the situation where some long LWs should be segmented into two
or more PWs, a Lexical Split Model (LSM) is applied to the long LWs. Experimental results prove that relatively constant results
with various training data can be obtained from a MM. The Transformation-Based Error Driven Learning (TBED) algorithm, for
its high performance of individual property, is applied in combination with the MM to improve the precision of PW segmentation.
Experiments show that among the three proposed models, the MM combined with TBED and LSM, leads to the best performance, in
which a precision of 93.00% and a recall of 93.23% are achieved. The perception test indicates that by using PWs as the lowest
prosodic units a speech sounds more natural and acceptable than by using LWs.
This paper is supported by NSFC Project (60503071); 973 Natural Basic Research Program of China (2004CB318102); Postdoctor
Science Foundation of P. R. China (20070420275). 相似文献
2.
3.
《Energy Conversion and Management》2005,46(13-14):2173-2184
It is indicated that modified carbon is a practical sorbent for removal of NO and SO2 from waste gases by the adsorption method. The ideal compositions for the prepared sorbent were 4.0 wt.% and 2.5 wt.% Na2CO3 and KOH at the experimental conditions, respectively, shortened as ACNaK2.5. Experimental investigation showed that the sorbent had a comparatively high breakthrough adsorption capacity of NO and SO2, about 5.8 g (NO + SO2)/100 g sorbent. It is indicated that a relatively high adsorption temperature would benefit the sorbent adsorption capacities on NO and SO2 at a certain space velocity and pressure. Further study revealed that the ACNaK2.5 sorbent had good regenerability at the experimental conditions, which implied that the ACNaK2.5 sorbent would be a useful sorbent for simultaneous removal of NO and SO2 from waste gases by adsorption. 相似文献
4.
《International Journal of Heat and Mass Transfer》2006,49(1-2):359-365
Physically substantiated boundary conditions for problems of heat transfer in infiltrated granular beds based on the two-temperature model which allow for the absence of interphase heat transfer on boundaries are formulated. It is shown that classical Dankwerts conditions would be applicable for gas. The problem of porous cooling at the boundary conditions of the 2nd and 3rd kind on the outer boundary is solved in a new formulation. 相似文献
5.
In this paper, we propose a new face recognition algorithm based on a single frontal-view image for each face subject, which considers the effect of the face manifold structure. To compare two near-frontal face images, each face is considered a combination of a sequence of local image blocks. Each of the image blocks of one image can be reconstructed according to the corresponding local image block of the other face image. Then an elastic local reconstruction (ELR) method is proposed to measure the similarities between the image block pairs in order to measure the difference between the two face images. Our algorithm not only benefits from the face manifold structure, in terms of being robust to various image variations, but also is computationally simple because there is no need to build the face manifold. We evaluate the performance of our proposed face recognition algorithm with the use of different databases, which are produced under various conditions, e.g. lightings, expressions, perspectives, with/without glasses and occlusions. Consistent and promising experimental results were obtained, which show that our algorithm can greatly improve the recognition rates under all the different conditions. 相似文献
6.
《Engineering Applications of Artificial Intelligence》2005,18(5):549-558
This paper describes two data analysis techniques adopted in a Decision Support System (DSS) that aids users in predicting oil production of an infill well. The system generates predictions in the form of a possible range of cumulative production and length of production life of an infill well. The system also shows the worst and best case scenarios based on different production curves so that the expert can examine the plots of predicted production rates for each existing well and decide which model gives the best fit. The production curve of each individual well was mathematically modeled so that production values beyond the historical data can be produced. Decline curve estimation and neural network approaches were adopted for data analysis in the system. The system was tested with data from two groups of wells from two different fields in Saskatchewan, Canada. Observations on the suitable duration that the historical data set should cover and a comparison among different curve estimation and neural network models are presented. 相似文献
7.
8.
科技期刊编辑专业化和学者化是保证期刊学术质量的关键 总被引:1,自引:0,他引:1
一般科技期刊刊载的论文内容都具有很强的专业性,这就要求科技期刊编辑必须具有丰富的专业知识和较高的学术水平才能胜任编辑工作.从编辑过程的选题组稿、论文初审、选择审稿专家和编辑加工四个方面对此进行了阐述,指出了提高科技期刊编辑的相关专业知识和学术水平的措施. 相似文献
9.
High speedsteel (HSS) ,ischaracterizedbyex cellenthardness ,wearresistance ,and goodredhardness .Recently ,HSSisappliedtomanufacturehotrollingrollstoproducestripsofgoodshapeandsmallcrownwithextendedrollservicelife[1,2 ] .TheHSSisappliedtomanufacturerollcollarfor… 相似文献
10.
《Composites Science and Technology》2007,67(7-8):1330-1339
In order to analyze the effect of an epoxidized natural rubber (ENR) and filler treatment on the morphology and behavior of natural rubber (NR) nanocomposites, blends of these polymers have been prepared. The nature and extent of the clay dispersions in the filled samples were evaluated by X-ray diffraction. In the presence of ENR, an exfoliated structure was obtained which suggests that enough rubbery polymer was incorporated into the interlayer spacing. The effect of clay in rubber compounds was analyzed through rheological, mechanical and swelling characterization. A sensible improvement in the nanocomposite properties was observed by the addition of organoclay. It has been deduced that the properties of the compounds strongly depend on the extent of the silicate nanolayers dispersion into the rubber matrices as well as on the organoclay type and elastomer compatibility. 相似文献