An Investigation on the Effects of Architectural Features on Acoustical Environment of Historical Mosques

In the historical period, different mosques were built in the Anatolian side; the differences in size, typology and style were affected by the climate conditions, cultural and social aspects, availability of materials and the construction techniques of the region they were built in. The ceiling structure, which is the most influencing factor for mosque acoustics, is designed with either curvilinear elements or a flat ceiling for mosques. In the context of our case study, the eight historical mosques in Turkey, with different materials and types of ceiling structures, are investigated in terms of acoustical characteristics in the main prayer hall. Acoustical data are collected by measurements to reveal how the formal differences and material change in ceiling structures affect the acoustic environments of mosques with similar volume. Distribution of acoustical parameters and the suitability of the values obtained through measurements are compared to reflect the effect of architectural features on the acoustical characteristics of the prayer hall.

The effects of different ceiling structures and plan typologies on acoustical conditions of historical mosques

Mosque is a building type used by Muslim people consists of speech and music rituals. Good acoustical condition in mosques is an important issue to provide desired acoustical environment for prayers and Imams during different worship rituals. Prayers need to feel individuality in praying and the sense of unity in recitation of the Quran, hymns. Worship activities need a high level of speech intelligibility and to satisfy prayers in the spiritual aspects which make people feel closed to the God. In the context of study, six historical mosques in Turkey, with different types of cover structures and plan typologies, are designated as study areas. The present study contains two methods which the first one is collecting acoustical data by measurements and the second consists of mathematical modelling software program. The purpose of study to investigate effects of different plan typology and ceiling structures on acoustical characteristics in mosques with similar volume. Also, distribution of acoustical parameters and the suitability of the values obtained through acoustic simulations and measurements to the recommended values are aimed to be investigated. As a result of the investigations, it was concluded that the objective acoustic parameters of mosques changed according to the geometric parameter properties.

Songs in the genus Uromenus (Orthoptera: Tettigoniidae: Ephippigerini): A review with new information about some species

With nearly 60 described forms Uromenus is the most species-rich genus of the tribe Ephippigerini, a west Palearctic group of flightless bush-crickets (katydids). As it is typical for bush-crickets, Uromenus males produce species-specific calling songs to attract females prepared to mate. These insects are relatively large and their songs have always components audible to humans. Nevertheless, acoustical information are available only for few species. Also the phylogenetic relationships of species and species groups are poorly known. In this paper we present new data on the song and morphology of several species (U. dyrrhachiacus, U. elegans, U. finoti, U. galvagnii, U. robustus, U. tobboganensis and U. innocentii) and give a review of all published acoustical data. Judging from the still few data, as in other Ephippigerini the song patterns often seem to contain species-group characteristics making them candidates to be used in phylogenetic studies. Additionally, we have studied the female stridulatory organs which are unique in structure in Ephippigerini and completely different from those of the males. Despite in Uromenus used only for defensive stridulation, possibly species-specific similarities in structure between males and females exist.

Digital Methods for the Study of the Nineteenth-Century Orchestra

The nineteenth century saw a number of significant changes in European musical culture, including changes in the size and nature of the orchestra and the rise of the modern conductor. The coordination and musical leadership of orchestras has taken a variety of forms historically, but from around the middle of the nineteenth century silent conducting gradually began to supplant other forms of time keeping and instrumental leadership in opera and concert orchestras. Little or no empirical work has attempted to investigate the musical, social and perceptual consequences of this development, largely due to the technical challenges that must be addressed. This article describes the development and implementation of innovative digital methods to provide a detailed and multifaceted picture of a large ensemble in action, investigating the consequences of different distributions of individual musical agency for: 1) musicians’ playing experiences; 2) ensemble coordination and expressive timing; and 3) listeners’ evaluations. These methods include a polling application, implemented on participants’ smartphones, to provide fast-turnaround feedback from orchestral musicians about their experiences of playing under different conditions; and the use of digital methods to analyse acoustical data from the individual instruments of an orchestral string section, to facilitate a quantitative analysis of orchestral togetherness. Analyses of the experiential, quantitative and listener data from a preliminary study with an orchestra of musicians from the Royal Academy of Music, London, are presented, together with a discussion of the insights that these methods provide. The article concludes by considering the prospects of these methods for investigating nineteenth-century rehearsal and performance practices.

Cell Yell!: Health Risks in Telehealth

Purpose The purpose of this study was to determine if the use of visual feedback can overcome the absence of side tone to control for vocal quality changes, specifically loudness, with speakerphone use. Method Ten men and 10 women held two 5-min conversations in pairs under audio-only and audiovisual communication conditions. Acoustical data and a number of conversational collisions (communication partners trying to speak at the same time) under each condition were compared. Results There were no statistically significant differences in acoustical measures of voice quality between audio-only and audiovisual conversations; however, vocal intensity was consistently 4 times more powerful than average face-to-face conversational intensity during both conditions. The number of conversational collisions was significantly less for the audiovisual condition as compared to the audio-only condition. Conclusion Results suggest that visual feedback did allow for modulation of conversational flow (fewer conversational collisions) but did not allow for modulation of vocal quality. Visual feedback did not overcome the absence of side tone and resulted in the same increased conversational loudness observed during the audio-only condition. As a result, remote conversational partners such as clients and telehealth practitioners are more susceptible to developing vocal health issues.

A Size-Controlled AFGAN Model for Ship Acoustic Fault Expansion

Identifying changes in the properties of acoustical sources based on a small number of sample data from measurements has been a challenge for decades. Typical problems are the increasing sound power from a vibrating source, decreasing transmission loss of a structure, and decreasing insertion loss of vibration mounts. Limited access to structural and acoustical data from complex acoustical systems makes it challenging to extract complete information of the system and, in practice, often only a small amount of test data is available for detecting changes. Although sample expansion via interpolation can be implemented based on the priori knowledge of the system, the size of the expanded samples also affects identification performance. In this paper, a generative adversarial network (GAN) is employed to expand the acoustic fault vibration signals, and an Acoustic Fault Generative Adversarial Network (AFGAN) model is proposed. Moreover, a size-controlled AFGAN is designed, which includes two sub-models: the generator sub-model generates expanded samples and also determines the optimal sample size based on the information entropy equivalence principle, while the discriminator sub-model outputs the probabilities of the input samples belonging to the real samples and provides the generator with information to guide sample size considerations. Some real data experiments have been conducted to verify the effectiveness of this method.

Typological Characteristics of the Khanty Vocalism Based on Data of Kazym and Surgut Dialects

The paper aims to compare and describe the system of the vowel phonemes in two Khanty dialects – Kazym dialect (the West-Khanty dialectal group) and Surgut dialect (the East-Khanty dialectal group) from the typological point. The statement is made that experimental phonetical data are necessary for typological generalizations in phonology. For the Surgut dialect, for which only subjective auditory descriptions have existed until recent times, experimental acoustical data based on new materials from field expeditions are presented. On the basis of the list including 130 lexemes read out by five informants, duration of the vowels, first and second formant frequencies are measured via Praat software. In the Surgut dialect 13 vowel phonemes are stated for the Trom-Agan idiom (/i:/, /i:/, /u:/, /e:/, /o:/, /ɔ:/, /a:/, /u/, /e/, /o/, /ɛ/, /ɔ/, /a/) and 12 phonemes for Yugan idiom (/i:/, /i:/, /u:/, /e:/, /o:/, /ɔ:/, /a:/, /u/, /e/, /o/, /ɛ/, /a/; at the place of the Trom-Agan /ɔ/ the Yugan /ɛ/ is being used). The new Surgut data are compared with the already published Kazym data. A typological generalization is made on the basis of the N. S. Trubetskoy’s ideas. The Khanty vocalism represents a mixed triangle-linear system. The first-syllable subsystem has a triangle typology with three timbre classes: front unrounded vowels; mid-row vowels with weak labialization; back rounded vowels. The subsystem has three degrees of height for the Kazym dialect and four degrees of height for the Surgut dialect. The not-first-syllable subsystem has a linear typology with one neutral class and opposition by height. The whole system has an opposition by two degrees of phonological length; the strength of this opposition can be rated as weak.