Laryngeal Vibratory Behavior in Traditional Noh Singing

The phonation of Noh, a traditional Japanese style of singing, was investigated using electroglot-tographic and acoustical analyses. The dynamics of the laryngeal vibratory behaviors were analyzed for the singing voice of the Noh play compared with natural speech based on the Electroglottography (EGG) pa-rameters, EGG waveform, spectrum, and spectrogram. The result shows that Noh singing is characterized by low open quotient and high speed quotient. Three types of phonations are used in the singing with pressed, Vocal-Ventricular Mode (VVM), and growl voices. It was hypothesized that the period doubling ob-served in the EGG signal was reflective of VVM, which was caused by the phase difference in the vocal and ventricular fold oscillations, while the damped peak amplitude in every other cycle in the EGG signal was the result of the oscillations of the aryepiglottic folds at a frequency of half of the fundamental frequency. Sub-harmonics generated by the supraglottal oscillations add unique timbre to the sounds. The results suggest that the combination of phonation types is the key factor in generating their peculiar voice qualities.     

建构理论在高职英语视听说教学中的运用

高职英语的教学目标是培养学生的英语综合运用能力,特别是听说能力。针对目前高职英语视听说课中存在的实际问题,文章将以建构主义学习理论为基础探讨如何改进高职英语视听说教学．旨在更加有效地提高高职英语教学质量。     

面向对象的教务管理系统数据库模式分析与设计

随着面向对象程序设计语言的崛起,作为面向对象分析和设计结果的类及其相互关系逐渐成为绝大多数应用系统的必然制品。本文以教务管理系统为项目背景,讨论了在面向对象的分析和设计过程中,从分析类及其相互关系进而完成对数据库模式设计的方法。     

以市场为导向培养商务英语专业学生的实践能力

目前,高校在商务英语教学中仍多重视课堂教学,而忽略了实践教学这一重要环节。只有真正贯彻理论联系实际的原则,充分认识实践教学在商务英语理论教学中的重要作用,才能真正有效地发挥商务英语服务于我国外贸的作用。本文结合商务英语专业建设实际和商务英语的市场需求,对在商务英语教学中如何培养学生实践能力进行了探索。     

网络环境下图书馆信息技术服务创新研究

网络环境下,由各数据库形成的信息资源网络以其丰富的资源和便捷的使用形式,深刻地改变着图书馆的信息服务工作,使图书馆信息服务模式呈现多样化.在这样的环境下,读者对信息技术服务的跨门户交叉检索和浏览、精品化的信息需求与专业化的知识服务要求以及个性化的服务要求愈来愈高.因此,立足于图书馆建设实际,结合读者的服务需求,从观念、技术、人才以及业务体系创新等方面来促进图书馆建设,以期最大限度地满足广大读者的信息需求.     

同轴插板式TEM-TE11模式转换器的设计与实验研究

 介绍了同轴插板式TEM－TE₁₁模式转换器的设计:在同轴波导内沿径向插入四块金属板,将同轴TEM模转变为扇形截面波导TE11模,通过控制插板的长度使不同扇形截面波导输出TE₁₁模的相位不同,最后在圆波导内形成TE₁₁模;通过在插板的前端设置角向均匀分布的金属杆,实现了模式转换器的良好匹配。实验测得模式转换器的辐射方向图轴向最大,与数值计算结果吻合良好,表明实验中模式转换器的输出模式与数值计算结果一致,从而验证了同轴插板式模式转换器的可行性。     

不同偏置电流下半导体激光器的输出模式数目

本文通过求解半导体激光器的多模速率方程组,得到了不同偏置电流下半导体激光器的输出模式数目(定义为输出谱线半宽度内的模式数目)的表达式,首次从理论上预计了在阈值电流附近半导体激光器的输出模式数目.实验结果表明,理论和实验吻合得很好.     

基于CEEMD-LSTM光伏短期功率预测

为解决传统机器学习方法在面对多变的环境因素和不平稳序列时导致光伏功率预测精度低的问题,提出一种基于完全经验模态分解(complete ensemble empirical mode decomposition,CEEMD)和长短期记忆神经网络(long short-term memory,LSTM)相结合的光伏短期功率预测模型.首先,充分考虑影响光伏出力的太阳辐照度、相对湿度、大气压力和空气温度4种环境因素,通过CEEMD将气象因素特征曲线分解为多模态特征数据,准确捕捉其不同的时间尺度和频率特征,进而充分保留环境数据的不平稳特征.其次,在此基础上,利用LSTM网络对多模态特征数据进行时间序列建模,旨在保留时间序列的季节性和不平稳特征,为后续建模提供更准确的输入特征.最后,通过对分解后的信号开展训练,根据输入数据的变化自适应调整预测模型参数,迭代生成特定场景下的预测模型,从而灵活应对实时环境变化,得到相应功率预测结果.在海南一孤立海岛分布式光伏电站37 kW子阵的8个月气象和功率数据集进行验证,实验结果表明,所提方法在保留环境数据细节和局部特性上具有显著优势,在不同气象条件均具有良好的自适应性,有效提高了光伏短期功率预测精度.     

Mode III fracture behavior of laminated composite with edge crack in torsion

A three-dimensional (3-D) finite element analysis was performed on a [90,(+45/−45)_n,(−45/+45)_n,90]_s class of laminated composites under the edge crack torsion (ECT) test configuration. Finite element delamination models were established and formulas for calculating the Mode III fracture toughness from 3-D finite element models were developed. The relations between the interlaminar fracture behavior and various configuration parameters were investigated and the effects of point loads, ends, geometry, Mode II interference, and friction were evaluated. Results showed that with proper selection of ECT specimen configuration and layup, the delamination could grow in pure Mode III in the middle region of the specimen. Specimen end effect played an important role in the ECT test. A Mode II component occurred in the end regions but it did not interfere significantly with the Mode III delamination state. Specimen dimension ratio, layup, and crack length exhibited significant effect on the interlaminar fracture behavior and the calculated strain energy release rates. However, friction between crackfaces was found to have negligible effect on the interlaminar properties.