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Achievements and Developments in Mass Models of Vocal Fold Vibrations
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作者 JI Mingjun LIU Boquan +2 位作者 LOU Zhewei LAN Jinwei FANG Jin 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期600-611,共12页
The proposed mass model of vocal fold vibration holds a significant importance in the auxiliary diagnosis and treatment of human vocal fold disorders.Mathematical models are proposed in aerodynamics and acoustics to s... The proposed mass model of vocal fold vibration holds a significant importance in the auxiliary diagnosis and treatment of human vocal fold disorders.Mathematical models are proposed in aerodynamics and acoustics to simulate vocal fold vibration during phonation.This has always been a hot topic in pathological linguistics research.Over the past few decades,researchers have designed various types of mass models of vocal fold vibration based on experiments.These models differ in principles,computational complexity,and degrees of freedom.Therefore,we classify and describe the mass models according to modeling methods.We summarize the research status and characteristics of different models,and based on this,we look forward to future research directions for vocal fold mass models. 展开更多
关键词 vocal fold vibrations mass model vocal fold disorders aeroacoustics
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Enhancing User Experience in AI-Powered Human-Computer Communication with Vocal Emotions Identification Using a Novel Deep Learning Method
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作者 Ahmed Alhussen Arshiya Sajid Ansari Mohammad Sajid Mohammadi 《Computers, Materials & Continua》 2025年第2期2909-2929,共21页
Voice, motion, and mimicry are naturalistic control modalities that have replaced text or display-driven control in human-computer communication (HCC). Specifically, the vocals contain a lot of knowledge, revealing de... Voice, motion, and mimicry are naturalistic control modalities that have replaced text or display-driven control in human-computer communication (HCC). Specifically, the vocals contain a lot of knowledge, revealing details about the speaker’s goals and desires, as well as their internal condition. Certain vocal characteristics reveal the speaker’s mood, intention, and motivation, while word study assists the speaker’s demand to be understood. Voice emotion recognition has become an essential component of modern HCC networks. Integrating findings from the various disciplines involved in identifying vocal emotions is also challenging. Many sound analysis techniques were developed in the past. Learning about the development of artificial intelligence (AI), and especially Deep Learning (DL) technology, research incorporating real data is becoming increasingly common these days. Thus, this research presents a novel selfish herd optimization-tuned long/short-term memory (SHO-LSTM) strategy to identify vocal emotions in human communication. The RAVDESS public dataset is used to train the suggested SHO-LSTM technique. Mel-frequency cepstral coefficient (MFCC) and wiener filter (WF) techniques are used, respectively, to remove noise and extract features from the data. LSTM and SHO are applied to the extracted data to optimize the LSTM network’s parameters for effective emotion recognition. Python Software was used to execute our proposed framework. In the finding assessment phase, Numerous metrics are used to evaluate the proposed model’s detection capability, Such as F1-score (95%), precision (95%), recall (96%), and accuracy (97%). The suggested approach is tested on a Python platform, and the SHO-LSTM’s outcomes are contrasted with those of other previously conducted research. Based on comparative assessments, our suggested approach outperforms the current approaches in vocal emotion recognition. 展开更多
关键词 Human-computer communication(HCC) vocal emotions live vocal artificial intelligence(AI) deep learning(DL) selfish herd optimization-tuned long/short K term memory(SHO-LSTM)
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Vocal characteristics of distress and reproductive vocalizations in North American wapiti 被引量:1
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作者 Cora Anne Romanow Tobias Riede Susan Lingle 《Current Zoology》 2025年第5期545-559,共15页
Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evi... Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evidence of biphonation and other nonlinear phenomena.Here,we analyze the acoustic structure of captive wapiti vocalizations to compare the male bugle with 3 categories of distress vocalizations:neonate distress(capture)calls,calf isolation calls,and adult female isolation calls.These 4 high-arousal call categories serve a common general function in recruiting conspecifics but occur in different behavioral contexts(capture,isolation,reproduction).Our goal was to distinguish characteristics that vary in graded steps that may correspond to an animal’s age or size from characteristics that are unique to the bugle.Characteristics of the high and loud fundamental(G0)varied in an age/size-graded manner with a decrease in minimum G0,an increase in the maximum and range of G0,with no evidence of sex differences.The nonlinear phenomena of deterministic chaos,biphonation,and frequency jumps were present in all 4 call categories and became more common from the distress vocalizations of neonates to calves to adult females to the male bugle.Two temporal characteristics sharply distinguished the bugle from the 3 categories of distress vocalizations:these included a prolonged call duration and a maximum G0 that occurred much later in the call for the bugle than for distress vocalizations.Our results suggest that distress vocalizations of different age groups and the reproductive bugle of wapiti share a high G0,with age/size-graded changes in G0 and nonlinear phenomena,but differ sharply in temporal characteristics. 展开更多
关键词 age and sex differences BIOACOUSTICS CERVUS distress vocalizations elk fundamental frequency nonlinear phenomena ONTOGENY production reproduction
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TikTok for Pop Vocal Music Education:The Guideline and Practical Cases 被引量:1
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作者 Zeyuan Hu 《Journal of Contemporary Educational Research》 2025年第5期247-251,共5页
With the development of new media technology and the popularity of the TikTok platform in China,a large number of popular vocal music teachers have flocked to online platforms for teaching.Online vocal music education... With the development of new media technology and the popularity of the TikTok platform in China,a large number of popular vocal music teachers have flocked to online platforms for teaching.Online vocal music education in China is undergoing a transformation and facing challenges.This study adopts an exploratory research approach,interviewing students learning pop vocal music,and observing popular pop teachers on TikTok.The advantages,disadvantages,techniques,and methods of domestic TikTok pop vocal music teaching were investigated and studied,and a series of experiences and suggestions for optimizing TikTok teaching were put forward.The results of this study are helpful for understanding the advantages and disadvantages of TikTok pop vocal music teaching and grasping the correct development direction.These guidance and suggestions can stimulate teachers’creativity and improve their vocal music teaching level. 展开更多
关键词 Online education Pop vocal TikTok Music teaching
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三维超声VOCAL技术评价子宫内膜容受性在胰岛素抵抗不孕患者中的应用价值
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作者 胡敏珊 区薛宜 朱雅芸 《影像技术》 2025年第5期46-51,共6页
目的:探讨三维超声VOCAL技术评估胰岛素抵抗不孕患者子宫内膜容受性的临床价值。方法:纳入2023年2月至2024年6月我院收治的胰岛素抵抗不孕患者50例(研究组)及同期正常孕龄妇女50例(对照组),均行三维超声VOCAL检查,比较两组内膜容积、VI/... 目的:探讨三维超声VOCAL技术评估胰岛素抵抗不孕患者子宫内膜容受性的临床价值。方法:纳入2023年2月至2024年6月我院收治的胰岛素抵抗不孕患者50例(研究组)及同期正常孕龄妇女50例(对照组),均行三维超声VOCAL检查,比较两组内膜容积、VI/FI/VFI参数及血清SHBG、HOMA-IR等指标。结果:研究组内膜容积([2.45±0.31)cm^(3)]、VI(7.74±1.36)、FI(20.46±3.67)、VFI(158.14±10.20)均显著低于对照组(P<0.05),血清SHBG([45.69±5.78)nmol/L]、HDL-C([1.36±0.35)mmol/L]水平亦低于对照组(P<0.05)。研究组血清T([8.58±2.58)ng/mL]、TG([2.11±0.36)mmol/L]、FPG([7.69±1.13)mmol/L]、2 h PG([10.24±1.69)mmol/L]、FINS([27.41±3.16)μIU/mL]、HOMA-IR(2.24±0.35)水平高于对照组(P<0.05)。Pearson相关性分析显示,内膜容积与血清SHBG(r=0.536,P<0.001)、HDL-C(r=0.574,P<0.001)水平呈正相关,与血清T(r=-0.584,P<0.001)、TG(r=-0.496,P<0.001)、FPG(r=-0.547,P<0.001)、2 h PG(r=-0.558,P<0.001)、FINS(r=-0.569,P<0.001)、HOMA-IR(r=-0.585,P<0.001)均呈负相关。VI与血清SHBG(r=0.587,P<0.001)、HDL-C(r=0.604,P<0.001)水平呈正相关,与血清T(r=-0.512,P<0.001)、TG(r=-0.536,P<0.001)、FPG(r=-0.523,P<0.001)、2 h PG(r=-0.514,P<0.001)、FINS(r=-0.525,P<0.001)、HOMA-IR(r=-0.496,P<0.001)均呈负相关。FI与血清SHBG(r=0.601,P<0.001)、HDL-C(r=0.551,P<0.001)水平呈正相关,与血清T(r=-0.555,P<0.001)、TG(r=-0.587,P<0.001)、FPG(r=-0.546,P<0.001)、2 h PG(r=-0.567,P<0.001)、FINS(r=-0.516,P<0.001)、HOMA-IR(r=-0.478,P<0.001)均呈负相关。VFI与血清SHBG(r=0.598,P<0.001)、HDL-C(r=0.527,P<0.001)水平呈正相关,与血清T(r=-0.511,P<0.001)、TG(r=-0.571,P<0.001)、FPG(r=-0.532,P<0.001)、2 h PG(r=-0.510,P<0.001)、FINS(r=-0.536,P<0.001)、HOMA-IR(r=-0.546,P<0.001)均呈负相关。结论:三维超声VOCAL技术可有效评估胰岛素抵抗不孕患者的子宫内膜容受性,为个体化治疗提供影像学依据。 展开更多
关键词 胰岛素抵抗不孕 子宫内膜容受性 三维超声vocal技术 应用价值
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Exploration of Innovative Approaches in Applying Information Technology to Vocal Music Teaching in University
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作者 Jingping Yi Yali Zhang 《Journal of Contemporary Educational Research》 2025年第8期198-204,共7页
With the rapid development of information technology and the advancement of educational modernization,the teaching mode of vocal music in colleges and universities is undergoing a new transformation,which complies wit... With the rapid development of information technology and the advancement of educational modernization,the teaching mode of vocal music in colleges and universities is undergoing a new transformation,which complies with the trend of digital age and brings new challenges.This paper explores the specific implementation path of artificial intelligence technology,virtual reality technology,big data technology and intelligent interaction technology in vocal music teaching in colleges and universities,aiming to inject new vitality into the traditional teaching mode and improve teaching quality and efficiency. 展开更多
关键词 Information technology Teaching reform Colleges and universities vocal music teaching Innovative approaches
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Khoomei:An Ancient Vocal Tradition
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《China Today》 2025年第12期F0003-F0003,共1页
KHOOMEI is a traditional throat-singing art created by the Mongolian ethnic group and is regarded as one of the oldest forms of this low rumbling vocal technique in the world.In 2006,Khoomei was included in China’s f... KHOOMEI is a traditional throat-singing art created by the Mongolian ethnic group and is regarded as one of the oldest forms of this low rumbling vocal technique in the world.In 2006,Khoomei was included in China’s first national list of intangible cultural heritage items,followed in 2009 by its inclusion on UNESCO’s Representative List of the Intangible Cultural Heritage of Humanity. 展开更多
关键词 low rumbling vocal technique throat singing Mongolian ethnic group UNESCO intangible cultural heritage
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Beyond amplitude:Phase integration in bird vocalization recognition with MHAResNet
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作者 Jiangjian Xie Zhulin Hao +2 位作者 Chunhe Hu Changchun Zhang Junguo Zhang 《Avian Research》 2025年第1期119-128,共10页
Bird vocalizations are pivotal for ecological monitoring,providing insights into biodiversity and ecosystem health.Traditional recognition methods often neglect phase information,resulting in incomplete feature repres... Bird vocalizations are pivotal for ecological monitoring,providing insights into biodiversity and ecosystem health.Traditional recognition methods often neglect phase information,resulting in incomplete feature representation.In this paper,we introduce a novel approach to bird vocalization recognition(BVR)that integrates both amplitude and phase information,leading to enhanced species identification.We propose MHARes Net,a deep learning(DL)model that employs residual blocks and a multi-head attention mechanism to capture salient features from logarithmic power(POW),Instantaneous Frequency(IF),and Group Delay(GD)extracted from bird vocalizations.Experiments on three bird vocalization datasets demonstrate our method's superior performance,achieving accuracy rates of 94%,98.9%,and 87.1%respectively.These results indicate that our approach provides a more effective representation of bird vocalizations,outperforming existing methods.This integration of phase information in BVR is innovative and significantly advances the field of automatic bird monitoring technology,offering valuable tools for ecological research and conservation efforts. 展开更多
关键词 Bird vocalization recognition Feature fusion Phase information Residual network
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三维超声VOCAL技术:一种精确测量子宫肌瘤体积的方法 被引量:2
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作者 蓝彩凤 刘永峰 +2 位作者 林敏 李晓连 李水平 《中国医学物理学杂志》 CSCD 2024年第10期1249-1255,共7页
目的:评估二维超声(2D-US)、三维超声VOCAL技术(3D-VOCAL)对子宫肌瘤体积(UMV)测量的精确性。方法:选取2022年10月~2023年4月于福建医科大学附属龙岩第一医院行子宫肌瘤外科手术治疗的患者45例,术前运用2D-US、3D-VOCAL对UMV进行测量,... 目的:评估二维超声(2D-US)、三维超声VOCAL技术(3D-VOCAL)对子宫肌瘤体积(UMV)测量的精确性。方法:选取2022年10月~2023年4月于福建医科大学附属龙岩第一医院行子宫肌瘤外科手术治疗的患者45例,术前运用2D-US、3D-VOCAL对UMV进行测量,与手术切除后的实际肌瘤体积进行比较,评估两种超声技术测量UMV的准确性及重复性。结果:3D-VOCAL测量肌瘤体积的一致性(ICC=0.992)高于2D-US(ICC=0.976),且3D-VOCAL在不同大小肌瘤中的ICC均高于2D-US(均P<0.001)。2D-US、3D-VOCAL、手术术后3组间UMV测值的体积在最大径<8 cm差异无统计学意义(P>0.05),而3组间在最大径≥8 cm差异有统计学意义(P<0.05);进一步两两分析显示,在最大径≥8 cm UMV中,2D-US与手术术后的UMV测值差异有统计学意义(P<0.05),3D-VOCAL与手术术后的UMV测值差异无统计学意义(P>0.05)。3D-VOCAL在不同观察者间及观察者内的一致性均优于2D-US。结论:3D-VOCAL对于术前UMV的测量优于2D-US,是一种简便、高效的可靠方法,为临床随访提供理论依据。 展开更多
关键词 子宫肌瘤 三维超声 vocal技术 二维超声 肌瘤体积
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Lack of response to conspecific juvenile vocalizations in two avian brood parasites
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作者 Rocío Prieto María Cecilia De Mársico +1 位作者 Juan C.Reboreda Romina C.Scardamaglia 《Current Zoology》 SCIE CAS CSCD 2024年第5期589-595,共7页
Juveniles of interspecific avian brood parasites need to locate and recognize conspecifics to continue their life cycle after being reared by individuals of another species.However,little is known about the recognitio... Juveniles of interspecific avian brood parasites need to locate and recognize conspecifics to continue their life cycle after being reared by individuals of another species.However,little is known about the recognition mechanisms and cues involved in this critical stage of their lives.It has been proposed that adult parasites could show some kind of parental behavior by actively searching and interacting with conspecific young,which in turn could serve the juveniles to learn and/or reinforce the learning of conspecific characteristics.Since acoustic communication is one of the main channels used by birds,if such form of parental behavior by adult avian brood parasites does exist,adult cowbirds should recognize and respond positively to vocalizations of conspecific juveniles.We experimentally tested whether adult shiny Molothrus bonariensis and screaming M.rufoaxillaris cowbirds respond positively towards acoustic signals of conspecific juveniles using two playback experiments,one conducted in semi-captivity and the other in the field.In both cases,we presented 3 types of playbacks to adults of both cowbird species:vocalizations of shiny cowbird juveniles,vocalizations of screaming cowbird juveniles,and white noise as a control.In the experiment in semi-captivity,no significant differences were found between treatments.In the field experiment,no conspecifics approached the playback area,but hosts of the species whose playback was played were attracted to the loudspeaker.In conclusion,our results do not support the predictions we tested from the parental behavior hypothesis and indicate that adult shiny and screaming cowbirds do not respond positively to acoustic signals of conspecific juveniles,at least not to the type of signals used in our experiments. 展开更多
关键词 brood parasitism fledglings Molothrus parental behavior hypothesis vocal recognition
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Image-Based Flow Prediction of Vocal Folds Using 3D Convolutional Neural Networks
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作者 Yang Zhang Tianmei Pu +1 位作者 Jiasen Xu Chunhua Zhou 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第2期991-1002,共12页
In this work,a three dimensional(3D)convolutional neural network(CNN)model based on image slices of various normal and pathological vocal folds is proposed for accurate and efficient prediction of glottal flows.The 3D... In this work,a three dimensional(3D)convolutional neural network(CNN)model based on image slices of various normal and pathological vocal folds is proposed for accurate and efficient prediction of glottal flows.The 3D CNN model is composed of the feature extraction block and regression block.The feature extraction block is capable of learning low dimensional features from the high dimensional image data of the glottal shape,and the regression block is employed to flatten the output from the feature extraction block and obtain the desired glottal flow data.The input image data is the condensed set of 2D image slices captured in the axial plane of the 3D vocal folds,where these glottal shapes are synthesized based on the equations of normal vibration modes.The output flow data is the corresponding flow rate,averaged glottal pressure and nodal pressure distributions over the glottal surface.The 3D CNN model is built to establish the mapping between the input image data and output flow data.The ground-truth flow variables of each glottal shape in the training and test datasets are obtained by a high-fidelity sharp-interface immersed-boundary solver.The proposed model is trained to predict the concerned flow variables for glottal shapes in the test set.The present 3D CNN model is more efficient than traditional Computational Fluid Dynamics(CFD)models while the accuracy can still be retained,and more powerful than previous data-driven prediction models because more details of the glottal flow can be provided.The prediction performance of the trained 3D CNN model in accuracy and efficiency indicates that this model could be promising for future clinical applications. 展开更多
关键词 vocal folds Computational fluid dynamics Machine learning 3D convolutional neural network
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A Study of the Effect of Sichuan Opera Singing on the Vocal Skills of Music Students
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作者 Jing Li Miao Yu 《Journal of Contemporary Educational Research》 2024年第6期161-165,共5页
The purpose of the article is to explore the effects of Sichuan opera singing on music majors’vocal skills,focusing on three key aspects:pitch test,assessment of rhythmic perception,and emotional expression.Through a... The purpose of the article is to explore the effects of Sichuan opera singing on music majors’vocal skills,focusing on three key aspects:pitch test,assessment of rhythmic perception,and emotional expression.Through a quasi-experimental design,100 music majors were selected as research subjects and divided into an experimental group that received Sichuan opera singing instruction and a control group that received traditional vocal instruction.The results showed that compared with the control group,the experimental group receiving Sichuan opera singing teaching showed significant improvement in pitch mastery,rhythm perception,and emotional expression. 展开更多
关键词 Sichuan opera singing Music students vocal skills EFFECT
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The Contribution of Vocal Music Education in Colleges and Universities to Cultural Inheritance and Innovation
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作者 Xiaomei Ma 《Journal of Contemporary Educational Research》 2024年第8期154-160,共7页
The importance of education and cultural inheritance is becoming increasingly prominent.Through literature review and empirical research,combining quantitative data and qualitative analysis,this paper assesses the tea... The importance of education and cultural inheritance is becoming increasingly prominent.Through literature review and empirical research,combining quantitative data and qualitative analysis,this paper assesses the teaching methods,curriculum,and student interest and participation in vocal music education in colleges and universities.The study found that vocal music education played a positive role in increasing students’participation in cultural activities,enhancing their identification with traditional music and improving their skills,despite problems such as inadequate teaching systems and homogenized curricula.In particular,the participation rate of students in cultural activities before and after the educational changes increased significantly from 31–54.7%to 62.4–83.6%,indicating that vocal music education can effectively stimulate students’enthusiasm for cultural participation.In addition,the strengthening of the teaching staff and innovations in teaching methods,such as the application of multimedia and virtual reality technologies,provide students with richer learning experiences and personalized learning paths. 展开更多
关键词 College vocal music education Cultural heritage Cultural innovation Cultural activity participation rate
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Vocal structure, behavior and partitioning of all 23 Pternistis spp. into homologous sound(and monophyletic) groups 被引量:2
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作者 Johann H.VAN NIEKERK 《Chinese Birds》 CSCD 2013年第3期210-231,共22页
The aims of this research were (1) to provide a description of spurfowl Pternistis spp. calls and their social context;(2) to describe the divergence of advertisement calls;and (3) to appropri-ate 23 spurfowl species ... The aims of this research were (1) to provide a description of spurfowl Pternistis spp. calls and their social context;(2) to describe the divergence of advertisement calls;and (3) to appropri-ate 23 spurfowl species to homologous sound groups which have been synthesized with recognized monophyletic groups within Pternistis spurfowls. Sound group partitioning was primarily based on male advertisement calls. A total of 218 recordings (rendering^300 identifiable calls) were analyzed covering 22 out of 23 spurfowl species in Africa. One species was assessed from written accounts. The repertoire size per spurfowl varies between 7 and 11 calls. Spurfowl calls were arranged into three broad categories including (1) advertisement calls;(2) maintenance calls including distress calls, juve-nile whining (“mews”), cheeps and comfort calls;and (3) male-female and female-offspring bonding calls. Spurfowl species were set out in eight sound groups of which five were more or less congruent with the monophyletic groups of Hall (1963), but sound groups produced more partitioning as Hall described only five groups relevant to Pternistis spp. The divergence of advertisement calls appar-ently minimizes hybridization between sympatric species but the“genetic distance”between spurfowl species is relatively small causing hybridization among spurfowl species. Despite the vocalizations of Hartlaub’s Spurfowl (P. hartlaubi) differing significantly from the rest of the spurfowls, sound analy-ses suggest that it remains within Pternistis. 展开更多
关键词 homologous sound groups vocal behavior DIVERGENCE phylogeny Pternistis vocal structure
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Vocal repertoire of Azure-winged Magpies(Cyanopica cyanus):A context-associated communication system 被引量:1
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作者 Xu Wang Fan Yu +1 位作者 Haozhong Si Zhongqiu Li 《Avian Research》 SCIE CSCD 2023年第1期45-53,共9页
Signals within animals’vocal communication are considered functional referential and context-specific.Even in the absence of the context,receivers are expected to acquire the information of calls and respond specific... Signals within animals’vocal communication are considered functional referential and context-specific.Even in the absence of the context,receivers are expected to acquire the information of calls and respond specificallyWhereas the framework was supported by plenty of evidence,its exhaustivity in describing all animal vocalisations has been questioned.Here,we investigated the vocal repertoire of a cooperatively breeding species,Azure-winged Magpie(Cyanopica cyanus),to present evidence for referential signals.The results showed that Azure-winged Magpies had a relatively large vocal repertoire,consisting of twelve distinct calls.These calls were associated with the context including movement,begging for food,contact,vigilance against predators,etc.However,even the predator-specific alarm calls would induce various responses of receivers.This implies that multiple pieces of information are involved in the vocalisation,which could be utilised by the receiver to select an appropriate response based on the surroundings.Our study gives a detailed description of the context and function of the vocal repertoire in Azure-winged Magpies,laying the foundation for further investigation on the developmental mechanisms of bird vocalisations.This study also suggests that the referential signals of animal vocalisations may not be limited to the context-specific responses of receivers and need to be discussed from a broader perspective. 展开更多
关键词 Amure wingeod Magpies Behavioural ontext Reerential sigmals vocal ammumication vocal repertoire
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基于Vocal的私网穿透的SBC(Session Border Controller)设计(英文)
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作者 刘发贵 饶鹏 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期26-30,共5页
随着技术的成熟,VoIP技术以更加迅猛的势头得到发展和普及,但是在这个过程中也不可避免的碰到一些困难和问题,VoIP应用如何穿越NAT的问题就是其中之一。VOCAL是完全基于SIP的VoIP开放源代码方案。如何穿越NAT也是用VOCAL系统开发VoIP服... 随着技术的成熟,VoIP技术以更加迅猛的势头得到发展和普及,但是在这个过程中也不可避免的碰到一些困难和问题,VoIP应用如何穿越NAT的问题就是其中之一。VOCAL是完全基于SIP的VoIP开放源代码方案。如何穿越NAT也是用VOCAL系统开发VoIP服务必须解决的问题。研究了NAT技术给VoIP服务带来的问题,并且就当前主流的NAT穿透方案进行探讨,然后在此基础上选择一个无须对现有设备进行任何改动的VOCAL系统穿越NAT方案———SBC。并以VO-CAL系统为对象,研究SBC在VOCAL系统中的设计。 展开更多
关键词 IP电话 vocal SIP协议 SBC NAT
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An Analysis of the Hoarse Speech Signals by the Three Mass Model of Vocal Cords *
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作者 程启明 陈雪丽 万德钧 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期81-85,共5页
A three mass model of vocal cords as well as mathematical expression of the model are discussed. Different kinds of typical hoarse speech due to laryngeal diseases are simulated on microcomputer and the effects of di... A three mass model of vocal cords as well as mathematical expression of the model are discussed. Different kinds of typical hoarse speech due to laryngeal diseases are simulated on microcomputer and the effects of different pathological factors of vocal cords on model parameters are studied. Some typical spectrum distribution of the simulated speech signals are given. Moreover, hoarse speech signals of some typical cases are analyzed by the methods of digital signal processing, including FFT, LPC, Cepstrum technique, Pseudocolor encoding, etc. The experiment results show that the three mass model analysis of vocal cords is an efficient method for analysis of hoarse speech signals. 展开更多
关键词 hoarse speech signal three mass model of vocal cords laryngeal diseases
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三维超声VOCAL技术评估隐睾患儿术后睾丸发育情况
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作者 陈泽坤 陈晓康 +2 位作者 戴泽艺 郑伟坤 李雅雅 《中国妇幼保健》 CAS 2021年第18期4361-4364,共4页
目的探讨三维超声VOCAL技术评估隐睾患儿术后睾丸发育情况和临床价值。方法选取2015-2018年在该院治疗的160例单侧隐睾患儿为研究对象,对其进行为期12个月的术后随访,采用三维超声VOCAL技术测定不同年龄组和不同隐睾类型患儿术前、术后... 目的探讨三维超声VOCAL技术评估隐睾患儿术后睾丸发育情况和临床价值。方法选取2015-2018年在该院治疗的160例单侧隐睾患儿为研究对象,对其进行为期12个月的术后随访,采用三维超声VOCAL技术测定不同年龄组和不同隐睾类型患儿术前、术后睾丸容积变化情况。结果三维超声VOCAL技术测定睾丸容积具有良好的重复性和一致性。术后12个月后,A组患儿睾丸容积术前术后比较[(0.556±0.268)ml vs.(0.419±0.243)ml],差异有统计学意义(t=2.483,P<0.05),而B组、C组比较,差异均无统计学意义(均P>0.05)。不同年龄组患儿可移动型隐睾术后随访睾丸容积均明显改善,差异均有统计学意义(均P<0.05),固定型隐睾各组术后发育未见明显变化。3组可移动型隐睾患儿术前、术后12个月睾丸容积百分率变化程度比较,差异均无统计学意义(均P>0.05);固定型隐睾患儿A组与B、C组之间比较,差异均有统计学意义(均P<0.05);B、C组比较,差异无统计学意义(P>0.05)。结论三维超声VOVAL技术可用于隐睾患儿睾丸容积测定和术后睾丸发育的评估。可移动型隐睾术后睾丸发育良好,可随访择期手术;固定型隐睾患儿在1岁以前,一经发现应尽早手术,有利于术后睾丸发育。 展开更多
关键词 三维超声 vocal技术 隐睾 术后 睾丸容积
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High frequency components in avian vocalizations
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作者 李建强 张雁云 张正旺 《Chinese Birds》 2011年第3期125-131,共7页
Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai N... Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai National Nature Reserve of Henan Province,China.We found varying degrees of high frequency components in the vocalizations of 14 species and in several of these species,the frequency of harmonics was up to the range of ultrasound.We suggest that more studies are required to determine whether the high frequency components in avian vocalizations have functions and what these functions are.In addition,the ability of birds to hear sounds in the high frequency range also requires re-examination. 展开更多
关键词 avian vocalization high frequency components ULTRASOUND FUNCTIONS
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