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991.
VDSM(超深亚微米)设计中互连线延迟已在电路延迟中起到决定性作用。在前期设计阶段考虑互连延迟问题已是当前研究的重要课题。建立以互连为中心的综合方法是当前的一个棘手问题,尚未有成熟的方法。提出一种面向互连延迟的综合策略,将前期设计定时规划,前期设计的线网规划和布局规划方法相融合,并在不同阶段给出了不同精度和复杂度的定时分析模型。另还给出了一个设计实例对综合策略予以了说明。 相似文献
992.
993.
The purpose of this study was (1) to determine the relationship between acoustic measures and auditory-perceptual dimensions of overall voice severity and pleasantness and (2) to evaluate the ability of acoustic and auditory-perceptual measures to discriminate normal from dysphonic voices. Thirty adult dysphonic speakers and six, age-matched normal control speakers were asked to provide oral reading samples of the Rainbow Passage. Acoustic analysis of the speech samples was used to identify abnormal phonatory events associated with dysphonia. The acoustic program calculated long-term average spectral measures, glottal noise measures, and those measures based on linear prediction (LP) modeling. Twelve adult listeners judged overall voice severity and pleasantness from the connected speech samples using direct magnitude estimation (DME) procedures. The acoustic measures accounted for 48% of overall voice severity and 40% of voice pleasantness for dysphonic speakers. The classification performance of the acoustic measures and auditory-perceptual measures was quantified using logistic regression analysis. When acoustic measures or auditory-perceptual measures were considered in isolation, classification was generally accurate and similar across measures. Classification accuracy improved to 100% when acoustic and auditory-perceptual measures were combined. These data provide further support for use of both auditory-perceptual evaluation and acoustic analyses for classifying and evaluating dysphonia. 相似文献
994.
两不同部件串联可修系统的可用度的一个新的计算方法 总被引:2,自引:0,他引:2
本用直接解一组不含时间t的一阶线性偏微分积方程而得到两不同部件可修系统的可用度。 相似文献
995.
董超俊 《五邑大学学报(自然科学版)》1997,(3)
在调查目前国内水产品冷库能耗情况的基础上,提出了基于节能的优化设计思想和设计方法,开发了更适合现场实际的优化设计模型及设计参数。同时还开发了节能的计算机辅助监控管理系统。 相似文献
996.
Valerie P.C. Lim Jennifer M. Oates Debbie J. Phyland Matthew J. Campbell 《Journal of voice》1998,12(1):68-77
This study investigated changes in maximum phonation time andacoustic and perceptual measures of voice following topical anesthesia and laryngeal endoscopy with the flexible endoscope. Forty-four females, aged 18–33 years and with normal voices, performed four vocal tasks: (a) 3-second /i/ prolongation, (b) maximum phonation time on /i/, (c) stepwise scale-singing, and (d) reading a standard passage. Subjects performed these tasks prior to anesthesia, after anesthesia, and again during laryngeal endoscopy. Voice samples were analyzed for jitter, shimmer, harmonic-to-noise ratio, speaking fundamental frequency, maximum phonational frequency range, maximum phonation time, harshness, and breathiness. Results demonstrated significant reductions in maximum phonational frequency range following anesthesia and, during laryngeal endoscopy, reductions in maximum phonation time and increases in speaking fundamental frequency, minimum fundamental frequency on scale-singing, and breathiness. Clinicians using laryngeal endoscopy for evaluation and management of vocal dysfunction should, therefore, consider the possible effects of these procedures on vocal functioning. 相似文献
997.
A 53-year-old man with severe vocal fold atrophy underwent bilateral type 1 thyroplasty and anterior commissure advancement. Postoperatively, he developed a strained voice with less projection and volume than prior to surgery. This was verified by objective assessment of vocal function. Videoendoscopy revealed bilateral false vocal fold fullness and blunting of the anterior commissure. Magnetic resonance imaging demonstrated cephalic migration of the posterior ends of the implants and retrusion of the anterior commissure segment. Surgical exploration revealed that the type 1 implants had rotated and buckled. The anterior commissure segment was rotated and displaced inferiorly, and its inferior surface was tethered to the cricoid by scar tissue. The implants were removed, the anterior segment was repositioned and rigidly fixed, and bilateral lipoinjection performed. Vocal function was significantly improved, and endoscopy revealed normal tension and length of the vocal folds and restoration of the anterior commissure. This case demonstrates the importance of stable fixation during laryngeal framework surgery 相似文献
998.
999.
力学中所研究的许多问题,都直接涉及到某一物理现象发生的整个过程,或者是过程中的某些状态。因此,相应地就引入了许多关于描述某些物理过程的过程量和用来描述某些特定的物理状态的状态量,从而来定量地分析、研究某些过程中这些物理量之间的变化关系及引起变化的原因。 相似文献
1000.
卢正启 《上饶师范学院学报》1995,(6)
从理论上计算了三层磁性耦合的磁化过程。假定每层膜具有单轴各向异性,且易轴方向垂直于膜面,各层磁化曲线都为矩形。第一层与第三层组成成份和膜厚完全相同。我们得到了各种各样磁化过程及其条件。尤其指出了得到矩形磁化过程条件。磁光记录需要矩形磁化过程,为进一步多层膜磁光记录研究提供了依据。 相似文献