Sound Control Research Articles

Weed Classification from Natural Corn Field-Multi-Plant Images Based on Shallow and Deep Learning.

Crop and weed discrimination in natural field environments is still challenging for implementing automatic agricultural practices, such as weed control. Some weed control methods have been proposed. However, these methods are still restricted as they are implemented under controlled conditions. The development of a sound weed control system begins by recognizing the crop and the different weed plants presented in the field. In this work, a classification approach of Zea mays L. (Crop), narrow-leaf weeds (NLW), and broadleaf weeds (BLW) from multi-plant images are presented. Moreover, a large image dataset was generated. Images were captured in natural field conditions, in different locations, and growing stages of the plants. The extraction of regions of interest (ROI) is carried out employing connected component analysis (CCA), whereas the classification of ROIs is based on Convolutional Neural Networks (CNN) and compared with a shallow learning approach. To measure the classification performance of both methods, accuracy, precision, recall, and F1-score metrics were used. The best alternative for the weed classification task at early stages of growth and in natural corn field environments was the CNN-based approach, as indicated by the 97% accuracy value obtained.

An extrapolation-based virtual sensing technique of improving the control performance of the FxLMS algorithm in a maritime environment

Several local active noise control (ANC) approaches based on Filtered-x Least Mean Square (FxLMS) algorithm have been designed to mitigate low frequency noise annoyance from undesirable acoustic sources, for which conventional passive techniques are ineffective. A fundamental limitation of local ANC is the small size of quiet zone that is extended around the error microphone. This means that the physical sensor should be mounted at the desired location of noise attenuation, which in most cases is practically inconvenient. In order to extend the zone of quiet close to the ears of a seated passenger who moves gently his head, a number of complicated and computationally heavy virtual sensing algorithms have been developed for ANC. The spatial performance of such a local active sound controller depends not only on the correlation properties of the primary sound field and the adaptation algorithm but also on the microphones spatial arrangement, the size and the number of the control sources. Thus, the objective of this work is to develop a simple, robust and computationally-efficient virtual sensing ANC algorithm of improving the performance of the conventional FxLMS. The main approach to do so is by using a feedforward ANC controller based on the combined solution of first-order pressure prediction technique and a mixed-error design integrating the FXLMS algorithm for enhancing the noise attenuation levels and shaping an extended silence zone. Aim of this work is also to estimate a simplified approach of the virtual secondary path in order to be more challenging in practical and commercial applications, while the ANC system can achieve adequate control performance.In an effort to test the extension degree of the silence zone generated at a fixed virtual location, low computational demand ANC headrest configurations, are investigated. The proposed schemes have been tested through a simulation model, a test rig and an experimental ANC system installed in a cabin mock-up. The computer-modeled and the experimental results demonstrate that the proposed local virtual sensing ANC algorithm maintains stability in all operating points, and works reliably and more effectively than the widely used conventional FxLMS algorithm.

Maximizing the acoustic contrast with constrained reconstruction error under a generalized pressure matching framework in sound zone control.

In sound zone control, the pressure matching (PM) algorithm is generally considered to achieve relatively low acoustic contrast (AC) regardless of the desired sound field. In this paper, we propose a generalized PM framework to generate a desired sound field with variable AC. The framework indicates that the choice of the desired sound field solely determines the AC performance of PM when the physical setting and acoustic environment remain unchanged. In the extreme, PM obtains the same AC as the acoustic contrast control method, which is widely accepted as the algorithm leading to the maximum AC. Based on the proposed framework, we design a variant coordinate descent algorithm to adjust the desired sound field by maximizing the AC under the constraint of the reconstruction error. Simulation results validate the efficacy and flexibility of the proposed framework in constrained sound zone control.

The Virtual Theremin: Designing an Interactive Digital Music Instrument for Film Scene Scoring

Abstract This paper presents a first prototype of a virtual Theremin instrument for accompanying film scenes with sound. The virtual Theremin is implemented as a hybrid application for the web. Sound control is achieved by capturing user gestures with a webcam and mapping the gestures to the corresponding virtual Theremin parameters pitch and volume. Different sound types can be selected. The application’s underlying research is part of the multi-modal digital heritage project KOLLISIONEN which targets to open up the private archive of the Russian film maker Sergej Eisenstein to a broader public in digital form. Eisenstein, a film theorist and pioneer of film montage, was particularly intrigued by the Theremin as an instrument for film sound design. The virtual Theremin presented here is therefore linked to a film scene from the 1929 Soviet drama “The General Line” by Sergej Eisenstein which was never set to music originally. In its first implementation state, the application connects music interaction design with digital heritage in a modular, flexible and playful way and uses contemporary web technologies to enable easy operation and the greatest possible accessibility.

Sound isolation systems and HVAC noise control: The hidden acoustical systems in music practice and rehearsal spaces

An important part of the design and acoustical performance of music education spaces are the sound isolation systems employed to reduce sound bleed between and among different spaces and the designed control of noise and vibration from building mechanical systems. Three case studies present challenges addressed in actual projects. One is a multi-story fine arts building at a university where all of the major acoustical spaces are built as rooms within rooms and the HVAC is distributed from a large rooftop mechanical room. The second is a single storey building at a public high school where primary, secondary, and tertiary sound separations, and HVAC system zones are clearly defined and describe the basic architecture of the facility. The third describes the steps in design required to transform significant acoustical difficulties in sound transmission and HVAC system noise into an expressive architectural and acoustical space built on a very modest budget.

Impedance tube measurements of 3D printed porous materials

The acoustics of porous media affects what materials are good for sound control in enclosed environments. The theories used in this area model porous materials as having continuous unconnected pores. The important physical factors in these theories are the porosity (ratio of pore volume to sample volume), tortuosity (ratio of pore length to sample depth), and flow resistivity (resistance to air flow through the sample). The models allow for calculation of acoustic properties but are not truly representative of most porous media. With the advent of 3D printing, it is possible to design and print 3D media with specific porosity and tortuosity characteristics. These materials can be used in an impedance tube to test the validity of the models being used. Porous plugs will be designed and 3D printed using stereolithography. The plugs’ acoustic properties will be measured in an impedance tube. The results of this project will provide data that can be used to refine the acoustic models of porous media.

Noise abatement study for an amplified music outdoor amphitheater

Amplified music outdoors poses many challenges in regard to sound abatement and requires a multi-disciplinary approach that includes sound system design and monitoring, programming considerations, architectural and landscaping sound control elements, and conditions for outdoor sound propagation including atmospheric, ground impedance, barrier and topographic effects. An interdisciplinary study was performed on the Brushy Creek Amphitheater in Hutto, Texas involving a local sound reinforcement company, audio equipment manufacturer, a local acoustical consulting firm, and a national atmospheric research group. This paper will provide the elements and findings of a multi-disciplinary investigation to minimize impact of a newly located amphitheater on the local community.

Interior Design of Administrative Buildings and Their Role in Achieving the Effective Performance of the User

Formality pattern، which gave a sense of formal equilibrium without any obstruction or confusion، resulting from a combination،Conclusions، inter alia، that the functional performance of administrative spaces is reflected in a comfortable internal environment. Using environmental control systems (air conditioning، sound control and fire detection systems)، they play an effective role In changing the inner atmosphere of spaces، it is also a key factor for psychological well-being،Reassurance (safety and security)، which in turn is reflected in the nature of the functionality of users within the internal space.

Clinical and Histological Features of Ovarian Hypoplasia/Dysgenesis in Alpacas.

Alpacas have a high incidence of congenital reproductive tract abnormalities, including ovarian hypoplasia/dysgenesis. Diagnosis of this condition is often challenging. The present study describes the clinical, ultrasonographic, and histologic features of ovarian hypoplasia/dysgenesis syndrome in 5 female alpacas. Additionally, serum AMH levels were compared between female alpacas diagnosed with ovarian hypoplasia/dysgenesis and a group of reproductively sound females (n = 11). The syndrome was suspected based on the presence of an infantile uterus and lack of ovaries by ultrasonography and laparoscopy. All females had normal female karyotype (n = 74 XX), but one presented a minute chromosome. The ovaries from these cases showed 3 main histological classifications: hypoplasia (n = 2), dysgenesis (n = 2), and dysplasia (n = 1). Serum AMH levels in affected females were significantly lower (P < 0.05) than those of reproductively sound control females. In conclusion, Serum AMH level may be helpful in the rapid diagnosis of ovarian hypoplasia/dysgenesis syndrome in alpacas. Furthermore, this syndrome in alpacas presents a variety of histological features. Different mechanisms may be involved in the derangement of ovarian differentiation. Further studies are needed to elucidate the causes of the syndrome.

An Advanced One-Step RT-LAMP for Rapid Detection of Little cherry virus2 Combined with High-Throughput Sequence-Based Phylogenomics Reveal Divergent Flowering Cherry Isolates.

Little cherry virus 2 (LChV-2, genus Ampelovirus) is considered to be the main causal agent of the economically damaging little cherry disease, which can only be controlled by removal of infected trees. The widespread viral disease of sweet cherry (Prunus avium L.) is affecting the survival of long-standing orchards in North America and Europe, hence the dire need for an early and accurate diagnosis to establish a sound disease control strategy. The endemic presence of LChV-2 is mainly confirmed using laborious time-consuming reverse-transcription (RT-PCR). A rapid reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay targeting a conserved region of the coat protein was developed and compared with conventional RT-PCR for the specific detection of LChV-2. This affordable assay, combined with a simple RNA extraction, deploys desirable characteristics such as higher ability for faster (<15 min), more analytically sensitive (100-fold), and robust broad-range diagnosis of LChV-2 isolates from sweet cherry, ornamental flowering cherry displaying heterogenous viral etiology and, for the first time, newly identified potential insect vectors. Moreover, use of Sanger and total RNA high-throughput sequencing as complementary metaviromics approaches confirmed the LChV-2 RT-LAMP detection of divergent LChV-2 isolates in new hosts and the relationship of their whole-genome was exhaustively inferred using maximum-likelihood phylogenomics. This entails unprecedented critical understanding of a novel evolutionary clade further expanding LChV-2 viral diversity. In conclusion, this highly effective diagnostic platform facilitates strategical support for early in-field testing to reliably prevent dissemination of new LChV-2 outbreaks from propagative plant stocks or newly postulated insect vectors. Validated results and major advantages are herein thoroughly discussed, in light of the knowledge required to increase the potential accuracy of future diagnostics and the essential epidemiological considerations to proactively safeguard cherries and Prunus horticultural crop systems from little cherry disease.

Monitoring silver diamine fluoride application with optical coherence tomography and thermal imaging: An in vitro proof of concept study.

ObjectivesThe purpose of this study was to show that optical coherence tomography (OCT) and thermal imaging can be used to monitor changes in the structure and activity of caries lesions over time after treatment with silver diamine fluoride (SDF).MethodsArtificial caries lesions were formed on enamel and dentin bovine blocks. Each block was partitioned into five windows with the central three windows exposed to a demineralization solution to create lesions: one sound window served as a sound control (SC), one sound window was exposed to SDF to serve as a test control (SCT), one lesion window served as a lesion control (LC), one lesion window received one application of SDF (L1), while the other lesion window received two applications of SDF (L2). Each window was scanned using OCT before SDF application, and every week subsequently, for 12 weeks after initial SDF treatment. Changes in the mean intensity and the width of the peak of increased reflectivity due to the lesion and SDF along with the intensity at a depth of 180 µm from the surface representing optical penetration through the lesion were monitored. Changes in the heat lost, ΔQ (temperature integrated over time) of each window during drying with air were also monitored using a thermal imaging camera. Transverse microradiography (TMR), and high‐resolution microscopy were also used for the analysis of selected samples.ResultsThe reflectivity and optical penetration of sound and lesion areas of enamel and dentin manifested significant changes in OCT images after SDF application. Thermal imaging showed significant differences in ΔQ indicative of permeability changes in the sound and lesion areas of enamel and dentin after SDF application.

No sound is more distracting than the one you're trying not to hear: delayed costs of mental control of task-irrelevant neutral and emotional sounds

BackgroundSuppressing intrusive thoughts can result in a post-suppression rebound effect where the same thoughts become hyperaccessible. The current study aimed to investigate if similar so-called rebound effects could be observed when people attempted to mentally suppress awareness of nonsensical auditory stimuli. Based on previous research on thought suppression and mental control in other domains, we hypothesized that attempting to suppress awareness of a task-irrelevant sound while under cognitive load would impact evaluations of the sound on affective dimensions and loudness, and result in increased general vigilance, as evidenced by faster responding on subsequent tasks.MethodsWe performed two experiments where participants in a suppression condition were initially instructed to mentally suppress awareness of a sound while performing a mentally challenging task. Participants in a control condition performed the same task without receiving any instructions regarding the sound. In Experiment 1, the sound was affectively neutral, while in Experiment 2 participants were presented with an inherently aversive (tinnitus-like) sound. After this initial phase, participants performed tasks measuring vigilance and attention, and were also asked to give subjective ratings of the sounds on a number of affective dimensions and loudness.ResultsIn Experiment 1, participants in the suppression condition showed faster response times on both a visual search task and an auditory spatial cueing task, as compared to participants in the control condition. Contrary to our predictions, participants in the suppression condition did not rate the distractor sound as louder than participants in the control condition, and there were no differences on affective dimensions. In Experiment 2, results revealed that participants in the suppression condition made more errors on a visual search task, specifically on trials where the previously suppressed sound was presented. In contrast to results from Experiment 1, participants in the suppression condition also rated the targeted sound as louder.ConclusionsThe findings provide preliminary support for a post-suppression rebound effect in the auditory domain and further suggest that this effect may be moderated by the emotional properties of the auditory stimulus.

Integrated Infection Control in the Maxillofacial Operation Theatre Considering COVID-19 Pandemic

AbstractThe pandemic of coronavirus disease 2019 (COVID-19) has influenced all services of life, including dentistry and oral and maxillofacial surgery. COVID-19 is primarily spread through contact with infected person, mucosal/respiratory droplets, fomites/contaminated surfaces/objects, and aerosol. Oral and maxillofacial surgeons are particularly at a high risk of transmission of COVID-19 due to proximity with patient during treatment. All cases should be assumed COVID-19 positive till proven otherwise because now asymptomatic patients also report to be COVID-19 positive. Such patients act as a carrier, shedding virus to expose the oral and maxillofacial surgeons. All elective procedures can be postponed. Only emergency cases that require immediate treatment should be done with proper standard precautions and sound infection control practice. During surgery, we require a maxillofacial operation theater (OT), which is divergent from other OTs due to the use of high-powered aerosol-generating instruments during surgery that increase the chances of spreading infection in the OTs. The aim of this paper is to integrate infection control in the OT for the management of confirmed or suspected COVID-19 patients throughout emergency treatment in oral and maxillofacial surgery.

SOUND CONTROL HOME AUTOMATION

This is a sound control home automation project that uses sound to turn on or off any electrical circuit. This is a circuit that works by creating sound from a distance. When a person claps or makes a sound that can be caught by a condenser microphone, the circuit's output light turns on. If another person claps, the light will turn off. The basic idea behind this project is that the condenser microphone catches up your claps, coughs, and the sound of a book being knocked off the table. It generates a weak electrical signal that is amplified by the transistor stage that follows. Each signal changes the state of two transistors coupled in a bistable multivibrator. One of these transistors controls a bulb through a heavier transistor. This is a sound-activated switch. Sound, for example, may be used to turn on or off a fan, a fluorescent light, a television, and other equipment.

IoT-based sound-level control for audio amplifiers: mosques as a case study

&lt;p&gt;&lt;span&gt;When using audio-amplifiers in the open, uneven distribution of sound makes people unpleasant because it is loud or unheared. This unfortunate situation arises because audio-amplifiers volumes are set according to the guess of sound technicians. Mosques, as an example, are distributed inside wide areas and fire Azan five times a day. Due to the relatively long distances between them, speed and direction of the wind impose setting sound levels prior to each Azan such that all the area is covered and the overlap is minimized. In this paper, we propose a system based on internet of things (IoT) model to control the sound level of each mosque in the community. An IoT device (one in a mosque) sets the level of sound fired by the audio-amplifier. To do that, a synchronized series of tones is fired from each node. Once a node hears these tones, the process of sound level control starts to indicate the distances to heared nodes. As the approximate distances between nodes are known, each node can calculate its suitable sound level. Results showed that the proposed system is effective in setting sound levels for mosques audio amplifiers.&lt;/span&gt;&lt;/p&gt;

Toolkit for individualization of head-related transfer functions using parametric notch-peak model

Although sound image control and sound field reproduction based on head-related transfer functions (HRTFs) have been studied for years, they have not been put to practical use. The main reason is that individual differences in HRTFs have not been overcome. In the present paper, we propose the parametric notch-peak HRTF model (PNP model), which can continuously change the parameters corresponding to individual differences in HRTFs by using knowledge of spectral notches and peaks and an HRTF database. We then develop a toolkit that can generate individual HRTFs by having the listener adjust the parameters. Finally, localization tests are carried out in order to examine the performance of the individualized HRTFs using the PNP model.

Sound Field Control in Surround Screen Speaker Array by WFS and CBT Algorithms

This paper proposes a method to solve the problem that the sound reproduction system cannot work when the movie screen is made by a sound-proof material such as LED. It is demonstrated in an array of 192 speakers to surround a screen for sound reproduction, called surround screen speaker array. The speaker array is built in an actual cinema. The sound field control algorithms are implemented by mixers. In order to improve the uneven sound field distribution and sound field aliasing caused by the speaker array, two algorithms WFS and CBT are used in this paper. A new control algorithm is proposed and demonstrated to improve the uniformity of the sound field distribution and reduce the sound field interference.

“Sporty” Feeling Control of Automobile Engine Sound with Sound Absorbers

“Sporty” Feeling Control of Automobile Engine Sound with Sound Absorbers

Indigenous knowledge promotion as a strategic pathway to sustainable structural transformation financing in Africa: lessons for the Middle East and North African economies

The quest for structural transformation has been a crucial challenge in Africa in spite of the huge amounts of aid disbursed, investments undertaken, policies implemented, etc. Notwithstanding several important reasons highlighted in the literature, they are insufficient because they focus on the role of financial resources but neglect non-financial issues and resources that are required to guarantee efficient mobilisation, utilisation and prudent management of public resources. Consequently, this paper examines these non-financial issues and resources through a systematic review of the relevant literature and analysis of their contents. The major finding was that most policy efforts at structurally transforming finance in Africa achieved little success because they were not rooted in the continent's cultures and traditions, which should be employed to enhance sound financial management and control systems.

Evaluation of Environmental Sound Pressure Level, Drawing of Noise-Isosonic Map Using Surfer V.19, and Prioritization of Engineering Noise Control Methods Using the Analytic Hierarchy Process (AHP): A Field Study in CGS Stations

Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments. Due to the high costs of exposure to excessive noise; continuous sound evaluation, propose and implement noise control plans in occupational environments is necessary. Thus, the present study aimed to review environmental sound measurements, drawing of noise maps, and prioritizing the engineering noise control methods using the Analytic Hierarchy Process (AHP). This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations (CGSs) of Kerman, Iran in 2021. The present study was done in two phases. In the first phase, six CGSs were investigated to measure and evaluate the noise. In addition, the noise map of a CGS was drawn using the Surfer software. Finally, the AHP was used in the second phase of the research to prioritize the control measures. In this phase, four criteria and ten alternatives were identified. According to first phase results, the sound pressure level (SPL) of the stations varied from 76 to 98 dBA. Besides, the majority of the studied stations had a sound level higher than 85 dBA (danger zone). The second phase of the study showed that out of the four evaluated criteria, the executability criterion had the highest impact and the cost criterion had the lowest impact on the selection of control measures with a weight of 0.587 and 0.052, respectively. Based on the results of prioritization of the alternatives, using a silenced regulator (weight of 0.223) and increasing the thickness of the tube (weight of 0.023) had the highest and lowest priorities among the alternatives, respectively. The use of engineering noise control methods such as using silenced regulators was the best way to control the noises of CGSs. Additionally; it is noteworthy that AHP is a practical method for prioritizing alternatives to achieve the most accurate decision-making. The results of AHP can be of great help to health and safety experts and managers in choosing the sound engineering control measures more precisely.