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111.
The formula and program for calculating the total and negative first harmonic interaction impedance from the data of “large
perturbation measurement” are given. This program is a part of the programs for CCTWT design. 相似文献
112.
113.
新型高温高密度W/O乳化钻井液的研制 总被引:1,自引:0,他引:1
研制了油包水乳化钻井液的基本配方,评价了其抑制性,热稳定性,以及抗水侵污能力,抗钻屑侵污能力,抗水泥侵污能力。现场应用表明,该体系具有较强的抑制作用,能很好地稳定井壁,保护油气层。 相似文献
114.
Sung D. Kwon Sung J. Song Dong H. Bae Young Z. Lee 《Journal of Mechanical Science and Technology》2002,16(9):1084-1092
The frequency dependency of Rayleigh surface wave is investigated indirectly by measuring the angular dependency of the backward
radiation of the incident ultrasonic wave in two kinds of degraded specimens by scuffing or corrosion. Then, the frequency
dependency is compared with the residual stress distribution or the corrosion-fatigue characteristics for the scuffed or corroded
specimens, respectively. The width of the backward radiation profile increases with the increase of the variation in residual
stress distribution for the scuffed specimens. In the corroded specimens, the profile width decreases with the increase of
the effective aging layer thickness and is inversely proportional to the exponent, m, in the Paris’ law that can predict the
crack size increase due to fatigue. The result observed in this study demonstrates high potential of backward radiated ultrasound
as a tool for nondestructive evaluation of subsurface gradient of material degradation generated by scuffing or corrosion. 相似文献
115.
Less may not be more,but it still counts: The state of social capital in Yeoville,Johannesburg 总被引:2,自引:2,他引:0
Kirsten Harrison 《Urban Forum》2002,13(1):67-84
116.
In the letter, two schemes of circuit partitioning for pseudo-exhaustive testing are described. The complexities of both are proved to be NP-complete. 相似文献
117.
118.
119.
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
120.
The physical gestures that operate music instruments are responsible for the qualities of the sound being produced in a performance.
Gestural information is thereby crucial for a model of music performance, paired with a model of sound synthesis where this
information is applied. The highly constrained nature of performers gestures makes this task suitable to be modeled via a
constraint-based approach, coupled with a strategy aimed at maximizing the gestural comfort of performers. We illustrate the
problem representation, the search strategy and a validation of the model against human performance. 相似文献