Audio Speaker Research Articles

Innovation Of Amaly Interpretation Learning At Primaganda Senior High School Jombang

This study aims to describe the learning innovation of Tafsir Amaly at SMA Primaganda Jombang. Tafsir Amaly is a local content subject that is included in the Primaganda High School curriculum. Tafsir Amaly is a Sufism-based interpretation developed by Thoriqoh Syadziliyah Al Mas'udiyah Jombang. This type of research uses a qualitative approach. Data collection methods: observation, interviews, and documentation. Technical analysis includes data reduction, data presentation, and concluding. To check the validity of the data, research extension, observation persistence, and triangulation were used. The results showed that the innovation of the implementation of Amaly's Tafsir includes the application of a combination of student-centered and conventional methods in the form of jigsaw cooperative methods, drills, discussions, questions and answers, peer tutorials, exemplary affective methods, and so on supported by the book Tafsir Amaly juz 1 and Quran song as a compliment. Then the teaching aids use qurany 1-5 if needed according to the learning theme of Amaly's Tafsir, Then the learning media can be supported by other means, for example, audio speakers, and so on.

A Robust Approach for Reproducing the Haptic Sensation of Sandpaper With Different Roughness During Bare Fingertip Interaction

When reproducing realistic virtual textures for bare finger interaction, an accelerometer attached to a fingernail is commonly used. This measurement depends on the dynamic conditions during the exploration action, and slight differences in roughness are difficult to acquire accurately because of masking by shivering, low-pass filtering by the finger tissue, and sensor accuracy. We propose a simpler yet robust approach based on the 3D measurement of the surface and compare it with the conventional approach. The 3D surface images of sandpaper with different degrees of roughness were captured using a 3D microscope, and the line roughness curve was transformed into an acceleration curve by quadratic differential transformation. The real-time acceleration and frictional force were measured by an accelerometer and force sensor for comparison. A haptic device replaying acceleration-based vibrations by two audio speakers and producing tangential force by a motor-controlled liner slide was developed for reproduction. We conducted experiments with participants to evaluate the reproduction approach. Experimental results showed that the conventional approach obtained sufficient discriminability with the assistance of force, whereas the proposed approach achieved higher reproducibility and discriminability by sole vibration. Thus, our approach provides a new reference for studies of bare finger interaction with rough surfaces.

THE IMPLEMENTATION OF TEACHING LISTENING TOEFL AT TEST ENGLISH SCHOOL

TOEFL test is requirement that must be done by some university, especially for English education department. From that situation, choose the right school to learn listening TOEFL. TEST English School is one of School or Course that focuses on the TOEFL preparation. This research conducted to describe the implementation of the TOEFL listening teachers at TEST English school in teaching TOEFL listening TOEFL. Descriptive qualitative method is used by this research. The data sources are the teachers of listening TOEFL, the director and 50 % students that learn listening TOEFL. Data collection technique in this research are interview, observation and documentation and three instrument there are interview guides, observation checklist and documentation. The data analysis technique in this research are reduction, data display and drawing conclusion. The result of this research are: 1) the teacher preparation in teaching listening TOEFL are syllabus, lesson plan and media, such as laptop, WhatsApp audio listening, projector, speaker, songs and Cambridge online dictionary, 2) the teachers do warming up before teaching, check the students’ homework, teaching by using clear explanation, good interaction with the students, solve the students’ problem, give the tips in doing the test and increase the students’ listening and give motivation to the students. 3) The evaluation done in every morning by doing test or scoring and done discuss the students’ problem in learning or doing the test in every Friday.

I Don't Understand What They Speak: Photovoice of Indonesian Higher Education Students

<span id="docs-internal-guid-38aec257-7fff-ee9f-22b3-415f227fd2e6"><span>This study discusses the problems and causes experienced by higher education students when listening to everything spoken by native speakers. They find it very difficult to understand speech spoken directly or from audio learning English. This makes them feel restless and uncomfortable in listening lessons and exams on campus while these subjects are very important for them as students. This study uses the photovoice methods in examining the problems experienced by several higher education students, so that it will focus more on the factors causing the problems and the problems experienced. The study was based on the experience of an English major in education. It involved four English speaking students and audio speakers. The study suggests that a parable occurred when an English education student understood the words of native speakers and audio speakers. It provides input to everyone associated with the study of English to recognize problems in understanding native speakers.</span></span>

A Corpus-Based Evaluation of Beamforming Techniques and Phase-Based Frequency Masking

Beamforming is a type of audio array processing techniques used for interference reduction, sound source localization, and as pre-processing stage for audio event classification and speaker identification. The auditory scene analysis community can benefit from a systemic evaluation and comparison between different beamforming techniques. In this paper, five popular beamforming techniques are evaluated in two different acoustic environments, while varying the number of microphones, the number of interferences, and the direction-of-arrival error, by using the Acoustic Interactions for Robot Audition (AIRA) corpus and a common software framework. Additionally, a highly efficient phase-based frequency masking beamformer is also evaluated, which is shown to outperform all five techniques. Both the evaluation corpus and the beamforming implementations are freely available and provided for experiment repeatability and transparency. Raw results are also provided as a complement to this work to the reader, to facilitate an informed decision of which technique to use. Finally, the insights and tendencies observed from the evaluation results are presented.

Elastomeric Haptic Devices for Virtual and Augmented Reality

AbstractSince the modern concepts for virtual and augmented reality are first introduced in the 1960's, the field has strived to develop technologies for immersive user experience in a fully or partially virtual environment. Despite the great progress in visual and auditory technologies, haptics has seen much slower technological advances. The challenge is because skin has densely packed mechanoreceptors distributed over a very large area with complex topography; devising an apparatus as targeted as an audio speaker or television for the localized sensory input of an ear canal or iris is more difficult. Furthermore, the soft and sensitive nature of the skin makes it difficult to apply solid state electronic solutions that can address large areas without causing discomfort. The maturing field of soft robotics offers potential solutions toward this challenge. In this article, the definition and history of virtual (VR) and augmented reality (AR) is first reviewed. Then an overview of haptic output and input technologies is presented, opportunities for soft robotics are identified, and mechanisms of intrinsically soft actuators and sensors are introduced. Finally, soft haptic output and input devices are reviewed with categorization by device forms, and examples of soft haptic devices in VR/AR environments are presented.

Sound to electric energy generating device

This paper presents the potential of an electromagnetic transducer device in a form of audio speaker that is used to capture sound waves to be converted into electricity. It is an interesting concept but less explored by researchers. The objective of the study is to measure the potential of electromagnetic transducer as a way to generate electricity. It deals with the creation of electricity through movement and magnetism. Sound waves can induce movement on the surface which in turn moves the transducer thus creating electricity. The source of sound was coming from an 8-inch subwoofer speaker with a frequency of 80 Hz that was held constant throughout the experiment. Furthermore, using simple linear regression analysis, the study showed that for every linear increase of sound intensity level and distance of the source, there is an exponential increase and an exponential decrease in the voltage root mean square (RMS) respectively. The functionality assessment of the device was statistically analyzed using completely randomized design. It was found that the energy level significantly increased as the sound intensity level increases given a fixed distance of 15 mm from the source. The device could generate enough energy to power small electronics such as light emitting diodes (LED), transistor and resistor.

An innovative MEMs peizo speaker

MEMs micro-speaker development has trailed behind MEMs microphone development by over two decades due to fabrication and acoustical challenges. While MEMs microphones only need to respond to minuscule displacement, generating sound energy requires both motor force and far higher volume velocity of the transducer mechanism. Recent development of a full bandwidth piezo-MEMs micro-speaker with a silicon diaphragm creates a rigid, light, fast responding transducer with high resistance to humidity and low thermal expansion. Fabricated using a monolithic MEMS semiconductor process eliminates calibration and driver matching. 20 Hz to 20kHz frequency response is delivered in occluded earbud, IEM, and hearing aid applications. The 20 kHz resonance peak provides a smoothly increasing response in the upper octaves. This extra amplitude allows for a significant increase in hearing aid gain and bandwidth over balanced armature transducers. The device is packaged in both top- and side-fire port configurations with earbud EVKs currently shipping. Integration of the amp, on the package substrate or SiP module, opens possibilities for more compact devices, longer battery life, lower cost, and more robust construction. The combination of audio fidelity, size, and speaker to speaker uniformity is not possible with traditional voice coil or hybrid MEMS approaches.

Digitalized Dust Alert System for Asthma Patients and their Care Takers

Bronchial allergies can be a lifestyle-wide continual disease starting to unusual breathing organ abilities in addition to problem in respiration. Nowadays, persistent coronary heart failure has turn out to be an extreme hassle in fact. This takes place while coronary heart muscular tissue gets weakened, will become prone and in the end interferes with the all-herbal pumping interest of heart. This is slowly influencing an ever-developing population market, culminating in standing up for one of the good sized motives of a hospital life for elderly residents. Asthma remains associated with significant preventable medical complications and mortality. Asthma is a life time chronic disease that leads to anomalous functions and difficulty in breathing. In this work, a complete as well as integrated health care version is defined allowing Chronic Cardiac arrest clients every day accumulates vital warning signs in your own home and in addition sends them the use of Internet of Things (IoT). Internet of things (IoT) is a network based on the physical systems that can be exhibited in the form of typical embedded system including electronic devices such as sensors. The connectivity of the items can make it feasible for those artifacts to alert in addition to amassing data. Self-monitoring allows doctors/physicians and patients to have control over real time monitoring and to provide on-time treatment. Portable monitoring different input sensors like temperature, humidity, heartbeat, air quality are used to measure readings, and audio speakers, LCD display, Raspberry pi, WiFi server are used to monitor patients health and alerting authority person or physicians frequently through IOT Server. The design shows that using sensors and IOT servers on mobile phones, we can have sufficient and real time monitoring of the symptoms of the asthma patients. The real time monitoring by the doctors in combination with smart phones applications for the children and their care takers can prevent some of these deaths in real time.

Generation of programmable dynamic flow patterns in microfluidics using audio signals.

Customised audio signals, such as musical notes, can be readily generated by audio software on smartphones and played over audio speakers. Audio speakers translate electrical signals into the mechanical motion of the speaker cone. Coupling the inlet tube to the speaker cone causes the harmonic oscillation of the tube, which in turn changes the velocity profile and flow rate. We employ this strategy for generating programmable dynamic flow patterns in microfluidics. We show the generation of customised rib and vortex patterns through the application of multi-tone audio signals in water-based and whole blood samples. We demonstrate the precise capability to control the number and extent of the ribs and vortices by simply setting the frequency ratio of two- and three-tone audio signals. We exemplify potential applications of tube oscillation for studying the functional responses of circulating immune cells under pathophysiological shear rates. The system is programmable, compact, low-cost, biocompatible, and durable. These features make it suitable for a variety of applications across chemistry, biology, and physics.

전기자동차의 사운드디자인 개선을 위한 CFRP 스피커의 음향 특성 연구

The noise characteristics of electric vehicles (EVs) and internal combustion engine vehicles (ICEVs) are different. Compared with vehicles with combustion engines, cars are quieter and have a lower interior overall sound pressure. The sound quality in the compartment of an EV degrades because of high frequency motor noise and road noise, which are not masked by engine noise. Therefore, to improve sound quality, an EV requires active sound generation (ASG) systems that can actively control interior sound quality. ASG requests an audio speaker with superior high frequency response to mask or control the level of high frequency noise. This study aims to develop carbon fiber reinforced plastic (CFRP) speakers with superior high frequency response. Using a commercial CFRP speaker, a numerical model for the proposed speaker was developed via a finite element (FE) method and experimentally validated. The frequency response of a CFRP speaker and general car audio speaker was analyzed using the developed FE model, and the sound radiation characteristics of two speakers were compared. The CFRP speaker was confirmed to have a superior high frequency response to a general audio speaker.

An experimental design for the control and assembly of magnetic microwheels.

Superparamagnetic colloidal particles can be reversibly assembled into wheel-like structures called microwheels (μwheels), which roll on surfaces due to friction and can be driven at user-controlled speeds and directions using rotating magnetic fields. Here, we describe the hardware and software to create and control the magnetic fields that assemble and direct μwheel motion and the optics to visualize them. Motivated by portability, adaptability, and low-cost, an extruded aluminum heat-dissipating frame incorporating open optics and audio speaker coils outfitted with high magnetic permeability cores was constructed. Open-source software was developed to define the magnitude, frequency, and orientation of the magnetic field, allowing for real-time joystick control of μwheels through two-dimensional (2D) and three-dimensional (3D) fluidic environments. With this combination of hardware and software, μwheels translate at speeds up to 50 µm/s through sample sizes up to 5 × 5 × 5 cm3 using 0.75 mT-2.5 mT magnetic fields with rotation frequencies of 5 Hz-40 Hz. Heat dissipation by aluminum coil clamps maintained sample temperatures within 3 °C of ambient temperature, a range conducive for biological applications. With this design, μwheels can be manipulated and imaged in 2D and 3D networks at length scales of micrometers to centimeters.

Semi‐portable solar power to facilitate continuous operation of technology in the field

Abstract The use of technology in field ecology is increasing rapidly and many applications require that equipment operates autonomously for weeks, months or even years. While reducing power requirements can extend the battery life of many field devices, research time frames are always limited without renewable power. However, commercially available units that provide autonomous solar power are either prohibitively expensive or too small to sustain continuous operation for many field devices. We describe a semi‐portable, field deployable solar unit that can provide sustainable power for a wide variety of field devices, including passive acoustic recorders, motion‐activated cameras, speakers and microcomputers. Depending on power needs, these units can be built in‐house for only a few hundred dollars (USD) with minimal access to tools or shop facilities. Further, we provide information on how to calculate power requirements and modify the system design to accommodate user needs. We have used these units effectively in the field for six research seasons, with continuous autonomous operation varying between 2 weeks and 8 months. Batteries and other parts are easily accessed and replaced if needed. Our example system can be modified to provide different output voltage (e.g. 12, 5 V), or to power audio speakers. We also describe a switch that can be placed within the unit to regulate power production to certain times of the day or week. Our aim is to facilitate the use of electronics in the field for ecologists who may lack funding, time or the expertise to design a system independently.

A Novel MEMS Speaker With Peripheral Electrostatic Actuation

We design and fabricate electrostatically actuated micro-speakers with circular diaphragms and peripheral electrode configuration. The novel electrode configuration mitigates the squeeze film damping and increases pull-in voltage when compared with the conventional parallel plate electrostatic transducer design. Finite element analysis shows that under dynamic conditions, we can achieve diaphragm deflections as much as 80 times the gap between the electrodes because of the proposed design. We compare the conventional design of electrostatically actuated audio speakers – where typical electrode separation gaps are around 60 to $100~{\mu }\text{m}$ and actuation voltages are in the range of 10 to 200 volts – with the proposed peripheral electrode design with an electrode separation gap of $1~ {\mu }\text{m}$ and actuation voltage ≤100 volts. The SPL obtained is comparable to the existing designs and ranges from 40 to 60 dB at 1 kHz at 1 cm with different sizes of the micro-speakers. The efficiency achieved with the proposed design is 100−4% at resonance which is at least two orders higher than the typically observed value for electrostatic micro-speakers. [2020-0134]

Audio System Fabricated With Flexible Hybrid Electronics

A printed flexible hybrid electronics (FHE) technology platform is described, which combines a thin-film audio speaker, printed interconnects, and printed passive components in a highly flexible system. Bimorph piezoelectric polymer speaker structures were developed and shown to give increased loudness compared with a single layer speaker, with good fidelity and easily recognizable sound. Speakers were fabricated on flexible thin polyimide substrates, which enables integration with printed electronics and other thin-film devices. Two demonstrator circuits were designed to operate the speakers and were fabricated using printed FHE techniques. One circuit was an amplifier for a portable music player, and the second provides a record and playback function using an audio integrated circuit. The fabrication of these devices included ink-jet printed interconnects and ink-jet printed resistors, which showed a good long-term stability and flexibility.

Improving speaker diarization for naturalistic child-adult conversational interactions using contextual information.

While deep learning has driven recent improvements in audio speaker diarization, it often faces performance issues in challenging interaction scenarios and varied acoustic settings such as between a child and adult (caregiver/examiner). In this work, the role of contextual factors that affect diarization performance in such interactions is analyzed. Factors that affect each type of diarization error are identified. Furthermore, a DNN is trained on diarization outputs in conjunction with the factors to improve diarization performance. The results demonstrate the usefulness of incorporating context in improving diarization performance of child-adult interactions in clinical settings.

Fansmitter: Acoustic data exfiltration from air-Gapped computers via fans noise

Computers that contain sensitive information are often maintained in air-gapped isolation. In this defensive measure, a computer is disconnected from the Internet - logically and physically - preventing accidental or intentional leakage of sensitive information outward. In recent years it has been shown that malware can leak data over an air-gap by transmitting sonic and ultrasonic signals from a computer speaker. In order to eliminate such acoustic covert channels, current best practice recommends the elimination of speakers in secured computers, thereby creating a so-called ‘audio-gapped’ system.In this paper, we present ‘Fansmitter,’ a malware that can acoustically exfiltrate data from air-gapped computers, even when audio hardware and speakers are not present. Our method utilizes the noise emitted from the CPU, GPU, and chassis fans. We show that a software can regulate the internal fans’ rotation speed in order to control their acoustic signal, known as blade pass frequency (BPF). Binary data can be modulated and transmitted over these audio signals to a remote microphone (e.g., a nearby smartphone). We present design considerations, including acoustic waveform analysis, data modulation and demodulation, and data transmission and reception. We evaluate the acoustic covert channel with various fans at different distances and present the results. We also discuss issues such as stealth, interference, and countermeasures. Using our method we successfully transmitted data from audio-less, air-gapped computers, to a mobile phone in the same room. We demonstrated an effective transmission at distances of 1–8 m, with a maximum bit rate of 60 bit/min per fan.

Wireless Power Hanger Pad for Portable Wireless Audio Device Power Charger Application

Since the portability feature has been introduced in headphone development, this device now uses a battery as the main built-in power. However, the battery has limited power capacity and a short lifetime. Battery substitution and a conventional battery charger method is an ineffective, inflexible inconvenience for enhancing the user experience. This paper presents an innovative portable audio device battery built-in charger method based on wireless power technology. The developed charging device is composed of a headphone hanger pad for the wireless headphone and a charging pad for the portable wireless audio device battery charging. Circular flat spiral air-core coil was designed and evaluated using a numerical method to obtain optimal vertical magnetic field distribution based on the proposed evaluation criteria. A coil has inner coil diameter of 25 mm, outer coil diameter of 47.8 mm, wire diameter of 0.643 mm, the pitch of 0.03 mm and a number of turns of 17 was chosen to be implemented on the transmitter coil. A magnetic induction technique was adopted in the proposed wireless power transmission module which was implemented using commercial off-the-shelf components. For experimental and validation purposes, a developed receiver module applied to the commercial wireless headphone and portable audio speaker have a built-in battery capacity at 3.7 V 300 mAh. The experimental results show that the wireless power hanger pad prototype can transfer a 5 V induction voltage at a maximum current of 1000 mA, and the power transfer efficiency is around 70%. It works at 110 kHz of operation frequency with a maximum transmission distance of about 10 mm and takes 1 h to charge fully one 3.7 V 300 mAh polymer lithium battery.

Determination of absolute turbulence amplitude by CO2 laser phase contrast imaging

Phase contrast imaging (PCI) has the important advantages of good sensitivity and applicability for the measurements of fluctuation and turbulence in magnetically confined plasma. However, the determination of the absolute amplitude of fluctuation is not well established. In this article, we propose to determine the absolute amplitude of fluctuation with calibration. The fluctuation measured by CO2 laser PCI (CO2-PCI) was confirmed by simultaneous measurements by using a HeNe heterodyne interferometer (HeNe-HI). In the test experiments, CO2-PCI and HeNe-HI measured sound fields, which are produced by the audio speaker (f=6∼18 kHz, k=0.09∼0.33 mm−1) and the piezoelectric transducer (f=72 kHz, k=1.3 mm−1). At f=13∼18 kHz, k=0.24∼0.33 mm−1, the differences between CO2-PCI and HeNe-HI were 20∼30%. At f=72 kHz, k=1.3 mm−1, the difference was less than ∼10%. On the other hand, the difference between PCI and HI becomes larger at f<13 kHz, k<0.24 mm−1. This is because in these regions some parts of the scattered and non-scattered radiation were not clearly separated inside and outside the groove of the phase plate. The procedure of the absolute value determination was applied to the detached plasma of LHD and compared with the measurement by using a CO2 laser heterodyne interferometer (CO2-HI). The signal of CO2- HI at f>20 kHz is almost at the same as the level of noise. On the other hand, the 2D-PCI signal is clearly higher than the level of noise in all the entire frequency region. At f < 20 kHz, the difference between CO2-HI and CO2-PCI becomes large. This is likely to be due to the wavenumber cut-off of CO2-PCI. Combining two diagnostics, it is possible to measure a wide range of fluctuations from the macroscopic to the microscopic scale.

Single-digit-micrometer thickness wood speaker

Thin films of several microns in thickness are ubiquitously used in packaging, electronics, and acoustic sensors. Here we demonstrate that natural wood can be directly converted into an ultrathin film with a record-small thickness of less than 10 μm through partial delignification followed by densification. Benefiting from this aligned and laminated structure, the ultrathin wood film exhibits excellent mechanical properties with a high tensile strength of 342 MPa and a Young’s modulus of 43.6 GPa, respectively. The material’s ultrathin thickness and exceptional mechanical strength enable excellent acoustic properties with a 1.83-times higher resonance frequency and a 1.25-times greater displacement amplitude than a commercial polypropylene diaphragm found in an audio speaker. As a proof-of-concept, we directly use the ultrathin wood film as a diaphragm in a real speaker that can output music. The ultrathin wood film with excellent mechanical property and acoustic performance is a promising candidate for next-generation acoustic speakers.