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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.
SONGXuwen LUYiqiang CAOYanqiu WANGLihua XINRenxuan 《稀有金属(英文版)》2002,21(1):20-23
The procedure of nebulization was studied with the introduction of ethanol into a lower power argon ICE It was found that as ethanol introduced, the physical properties of solutions changed, which results in an improvement on the nebulization efficiency. An empirical relationship between the concentration of the aerosol and the solution properties ( viscosity, density, and surface tension) is presented. 相似文献
3.
新型超高相对分子量阳离子聚丙烯酰胺的合成 总被引:8,自引:0,他引:8
研究了由过硫酸铵、甲醛次硫酸氢钠、功能性单体 DA及其它助剂组成的低温复合引发体系引发丙烯酰氧乙基三甲基氯化铵 (AETMAC)与丙烯酰胺 (AM)水溶液绝热聚合。考察了影响共聚物特性黏数[η]的因素 :单体浓度 1 8%~ 3 2 % ,引发剂浓度 (9~ 3 0 ) mg/L ,功能单体浓度 (2 .9~ 2 3 .2 )× 1 0 - 3mol/L。由该低温复合引发体系在适宜条件下引发 AETMAC/AM共聚合 ,可得到溶解性能很好、阳离子度为 1 0 %~70 % ,分子量 (1~ 2 )× 1 0 7的 P(AETMAC-AM)干粉。 相似文献
4.
Jianzhong Qi Rui Zhang Yanqiu Wang Andy Yuan Xue Ge Yu Lars Kulik 《World Wide Web》2014,17(6):1261-1293
We propose and study a new type of location optimization problem, the min-dist location selection problem: given a set of clients and a set of existing facilities, we select a location from a given set of potential locations for establishing a new facility, so that the average distance between a client and her nearest facility is minimized. The problem has a wide range of applications in urban development simulation, massively multiplayer online games, and decision support systems. We also investigate a variant of the problem, where we consider replacing (instead of adding) a facility while achieving the same optimization goal. We call this variant the min-dist facility replacement problem. We explore two common approaches to location optimization problems and present methods based on those approaches for solving the min-dist location selection problem. However, those methods either need to maintain an extra index or fall short in efficiency. To address their drawbacks, we propose a novel method (named MND), which has very close performance to the fastest method but does not need an extra index. We then utilize the key idea behind MND to approach the min-dist facility replacement problem, which results in two algorithms names MSND and RID. We provide a detailed comparative cost analysis and conduct extensive experiments on the various algorithms. The results show that MND and RID outperform their competitors by orders of magnitude. 相似文献
5.
CHEN Xiaodong YANG Cui XIANG Pei LIU Peng SHAO Xiaopeng ZHANG Xiaolei LV Yanqiu 《西安电子科技大学学报(自然科学版)》2017,44(3):61
The transient characteristics can be significantly affected by the interface trap. In order to reveal the intrinsic mechanism and provide some references for the design of detectors, the interface trap effect on the transient characteristics of a back-illuminated photovoltaic InSb infrared detector is studied with two-dimensional simulations. The relationships between interface traps and some key physical parameters, such as the hole concentration, the recombination rate and the electric field, are analyzed to reveal the intrinsic mechanisms of the influence of the interface traps on the transient characteristics. Studies show that with the increase of the interface trap density, the recombination rate and the electric field near the interface increase, the hole concentration decreases, and the “black holes” in current density distribution appear and move forward to the pn junction. And the transient photoresponse decreases with the increase of the interface trap density. 相似文献
6.
目的研究胶粘剂对酚醛泡沫板脆性与粉化性的危害,提出通过界面剂处理来阻断胶粘剂对酚醛泡沫板损害的方法.方法采用断裂力和回弹率两种方法测试酚醛泡沫板的脆性,砂纸粉末法测试酚醛泡沫板的粉化度,通过红外光谱研究两种性能变化的原因.结果Ca(OH)2浸泡和胶粘剂粘结后出现紫红色物质均对泡沫板的脆性和粉化性能产生负面影响.经Ca(OH)2浸泡与原样相比断裂力减小,回弹率和粉化度增加,最大差值分别为8.12N、4.61%、3.24%.胶粘剂粘结后酚醛泡沫试样断裂力和回弹率均减小,粉化度增加,最大差值分别为20.58N、7.25%、4.49%.自然晾晒、粘结胶粘剂潮湿养护和Ca(OH)2浸泡的酚醛泡沫板粉化度相对于原样依次增大,最大粉化度分别为12.56%、11.02%、8.91%、8.27%.结论界面剂的使用,有效地阻断了胶粘剂和酚醛泡沫板的直接接触,因此能够降低泡沫板脆性破坏与粉化增加速度,可以应用于工程实践中. 相似文献
7.
Yuhang Zhang Baojiu Chen Xizhen Zhang Xiangping Li Jinsu Zhang Sai Xu Xin Wang Yanqiu Zhang Li Wang Desheng Li Hai Lin 《Journal of the American Ceramic Society》2021,104(1):350-360
Lighting sources with full-color visible output are widely preferred in practical applications. In addition, modern lighting sources also tend to be intelligentized, and the intelligentization asks for smart luminescence materials. In this work, we attempt to develop novel full-color emitting material with temperature sensing and thermochromatic ability. To this end, the Cu2+ is successfully reduced to Cu+ which is incorporated into the germanate glasses. The glasses are prepared via a melt-quenching technique using graphite powders as reducing reagent. The supper-broadening of the excitation and the emission spectra of Cu+ in the germanate glasses are observed. Full-color emission is realized by introducing Tm3+ as co-dopant to provide the blue component in the spectra. The energy transfer behavior between Cu+ and Tm3+ is investigated, and it is found that these two luminescence centers are independently existent without energy transfer between them. The chromatic properties of the Cu+/Tm3+ co-doped glasses are tuned by Tm3+ concentration and excitation wavelength. The temperature sensing based on the fluorescence intensity ratio technique is demonstrated, and a constant sensitivity for the temperature detection is obtained. Moreover the thermochromatic property is also investigated, and it is found that the studied Cu+/Tm3+-doped glasses exhibit excellent thermochromatic performance. 相似文献
8.
9.
语义角色除了受句法结构限制之外,同词汇的语义特征也有着紧密的内在联系。对于一些仅依靠句法分析不能很好解决的角色标注问题,如句法结构相同的两个成分所对应的角色分别为完全不同的施事、受事角色的情况,可以通过引入一些词汇语义特征来进行处理。该文基于北京大学的语义词典CSD,引入了配价数、主客体语义类等词汇语义特征来进行语义角色标注研究。10折交叉验证的结果显示,通过引用词汇语义特征,所有角色标注的总体评价F值比单纯使用句法特征上升了1.11%,而其中Arg0和Arg1角色标注的F值达到93.85%和90.60%,比仅使用句法特征进行角色标注分别提高了1.10%和1.26%。 相似文献
10.
2,4-二氯-5-氟苯乙酮合成工艺研究 总被引:1,自引:0,他引:1
对2,4-二氯-5-氟苯乙酮的合成工艺进行了研究。以2,4-二氯氟苯和乙酰氯为原料,在催化剂AlCl3存在下反应,产物经溶剂萃取、蒸馏、结晶分离得产品。通过实验确定了最佳原料配比、反应温度、反应时间等工艺参数,选择溶剂A为萃取剂,产品收率可达80%左右。 相似文献