Audible Signal Research Articles

New Concept Design of Directional Rumble Strips for Deterring Wrong-Way Freeway Entries

Drivers who make wrong-way entries onto freeways pose a serious risk to the safety of other motorists and themselves. As a new countermeasure to mitigate the wrong-way entry issue, directional rumble strips (DRSs) were designed to generate elevated noises and vibrations to warn against wrong-way drivers and a normal level of stimuli to slow down right-way traffic. Five conceptual designs were developed based on Department of Transportation (DOT) guidelines, existing transverse rumble strips implementations, and input from rumble strip vendors. A national survey and extensive field tests were performed to verify the effectiveness of the proposed configurations. Acoustic and tactile signatures of the DRSs were measured by a specially equipped passenger car under different speed categories. The results indicated that the tested patterns could provide similar sound and vibration levels in the wrong-way direction as the existing transverse rumble strips (61.8–80.0 dBA sound signals and 1.1–1.4 g vibrations). The statistical and comparative analyses identified three DRS configurations that could produce greater audible and tactile signals in the wrong-way direction than the right-way direction, thereby serving the purpose of alerting inattentive wrong-way drivers while offering good visual attentiveness and applicability.

Does Pain Have a Role When It Comes to Tourniquet Training?

One of the greatest conundrums with tourniquet (TQ) education is the use of an appropriate surrogate of hemorrhage in the training setting to determine whether a TQ has been successfully used. At our facility, we currently use loss of audible Doppler signal or loss of palpable pulse to represent adequate occlusion of vasculature and thus successful TQ application. We set out to determine whether pain can be used to indicate successful TQ application in the training setting. Three tourniquet systems (a pneumatic tourniquet, Combat Application Tourniquet® [C-A-T], and Stretch Wrap and Tuck Tourniquet™ [SWAT-T]) were used to occlude the arterial vasculature of the left upper arm (LUA), right upper arm (RUA), left forearm (LFA), right forearm (RFA), right thigh (RTH), and right calf (RCA) of 41 volunteers. A 4MHz, handheld Doppler ultrasound was used to confirm loss of Doppler signal (LOS) at the radial or posterior tibial artery to denote successful TQ application. Once successful placement of the TQ was noted, subjects rated their pain from 0 to 10 on the visual analog scale. In addition, the circumference of each limb, the pressure with the pneumatic TQ, number of twists with the C-A-T, and length of TQ used for the SWAT-T to obtain LOS was recorded. All 41 subjects had measurements at all anatomic sites with the pneumatic TQ, except one participant who was unable to complete the LUA. In total, pain was rated as 1 or less by 61% of subjects for LUA, 50% for LFA, 57.5% for RUA, 52.5% RFA, 15% for RTH, and 25% for RCA. Pain was rated 3 or 4 by 45% of subjects for RTH. For the C-A-T, data were collected from 40 participants. In total, pain was rated as 1 or less by 57.5% for the LUA, 70% for the LFA, 62.5% for the RUA, 75% for the RFA, 15% for the RTH, and 40% for the RCA. Pain was rated 3 or 4 by 42.5%. The SWAT-T group consisted of 37 participants for all anatomic locations. In total, pain was rated as 1 or less by 27% for LUA, 40.5% for the LFA, 27.0% for the RUA, 43.2 for the RFA, 18.9% for the RTH, and 16.2% for the RCA. Pain was rated 5 by 21.6% for RTH application, and 3 or 4 by 35%. The unexpected low pain values recorded when loss of signal was reached make the use of pain too sensitive as an indicator to confirm adequate occlusion of vasculature and, thus, successful TQ application.

Application of audible sound signals for tool wear monitoring using machine learning techniques in end milling

Due to the demands of Computer-Integrated Manufacturing (CIM), the Tool Condition Monitoring (TCM) system, as a major component of CIM, is essential to improve the production quality, optimize the labor and maintenance costs, and minimize the manufacturing loses with the increase in productivity. To look for a reliable, efficient, and cost-effective solution, various monitoring systems employing different types of sensing techniques have been developed to detect the tool conditions as well as to monitor the abnormal cutting states. This paper explores the use of audible sound signals as sensing approach to detect the cutting tool wear and failure during end milling operation by using the Support Vector Machine (SVM) learning model as a decision-making algorithm. In this study, sound signals collected during the machining process are analyzed through frequency domain to extract signal features that correlate actual cutting phenomenon. The SVM method seeks to provide a linguistic model for tool wear estimation from the knowledge embedded in this machine learning approach. The performance evaluation results of the proposed algorithm have shown accurate predictions in detecting tool wear under various cutting conditions with rapid response rate, which provides the good solution for in-process TCM. In addition, the proposed monitoring system trained with sufficient signals collected from different positions has been proved to be position independent to monitor the tool wear conditions.

Visible but wide QRS complexes are associated with false asystole alarms

Alarm fatigue in the ICU setting has been well documented in the literature. The ICU's high-intensity environment requires staff's vigilant attention, and distraction from false and non-actionable alarms pulls staff away from important tasks, creates dissatisfaction, and is a potential patient safety risk if alarms are missed or ignored. This project was intended to improve patient safety by optimizing alarm systems in a cardiovascular surgical intensive care unit (CVSICU). Specific aims were to examine nurses' attitudes toward clinical alarm signals, assess nurses' ability to discriminate audible alarm signals, and implement a bundled set of best practices for monitor alarm reduction without undermining patient safety.CVSICU nurses completed an alarm perception survey and participated in alarm discriminability testing. Nurse survey data and baseline monitor alarm data were used to select targeted alarm reduction interventions, which were progressively phased in. Monitor alarm data and cardiorespiratory event data were trended over one year.Five of the most frequent CVSICU monitor alarm types—pulse oximetry, heart rate, systolic and diastolic blood pressure, pulse oximetry sensor, and ventricular tachycardia > 2—were targeted. After implementation, there was a 61% reduction in average alarms per monitored bed and a downward trend in cardiorespiratory events.To reduce alarm fatigue it is important to decrease alarm burden through targeted interventions. Methods to reduce non-actionable alarms include adding short delays to allow alarm self-correction, adjusting default alarm threshold limits, providing alarm notification through a secondary device, and teaching staff to optimize alarm settings for individual patients.

Endoscopic Doppler Probe in the Diagnosis and Management of Upper Gastrointestinal Hemorrhage

Through-the-Scope (TTS) endoscopic Doppler ultrasound probe technology is a tool that has garnered interest for the evaluation of variceal and non-variceal bleeding. We describe two cases in which endoscopic Doppler probe guided diagnosis and management of two patients with upper gastrointestinal hemorrhage. A 55 year old African American male with history of nephrectomy for a T1N0M0 renal cell carcinoma,end stage renal disease on hemodialysis presented to the emergency department after an episode of melena.Hemoglobin on presentation was 7.1 g/dl. During the hospitalization,he underwent several endoscopies and tagged RBC scan, none of which could identify a source of bleeding.EUS was performed to assess the gastric fundus for gastric varices or gastric Dieulafoy, which was unremarkable.Endoscopy with Doppler probe was subsequently performed and identified a 2 mm. red spot in the duodenal bulb with strong arterial signal compatible with a duodenal Dieulafoy lesion,which was successfully treated.The patient did not have further episodes of bleeding and hemoglobin stabilized at 8 g/dl. A 32 year old male with recent history of binge drinking and emesis presented with gastrointestinal bleeding.On arrival, the patient was hemodynamically stable.Laboratory values were significant for hemoglobin of 13.5 g/dl and platelets of 88 x109/L.On initial endoscopic evaluation, a Mallory-Weiss tear was seen and thought to be the etiology of bleeding.Further evaluation with endoscopic Doppler US probe revealed an audible venous Doppler signal that was consistent with a varix, and closer endoscopic inspection revealed a junctional gastroesophageal varix with a tear.Three bands were successfully placed and post-band ligation Doppler signal was absent. In summary, we present two patients in whom a TTS endoscopic Doppler ultrasound probe guided the diagnosis and subsequent management of acute upper gastrointestinal hemorrhage.In the first patient,it helped to identify an obscure source of GI bleeding after multiple endoscopies and a bleeding scan.In the second patient,it served to discover an unsuspected bleeding etiology of a junctional varix when a Mallory-Weiss tear was initially suspected which then resulted in change of clinical management.Though the literature has identified its utility in peptic ulcer hemorrhage,these cases highlight its use in other causes,which may translate to downstream effects, such as decreasing morbidity and mortality related to GI hemorrhage.Figure: Case One: Two mm red spot in duodenal bulb (arrow), seen during repeat EGD on day 6.Figure: Case Two: Initial endoscopy showing a tear around GE junction (arrow), thought to represent Mallory- Weiss tear.Figure: Case Two: Junctional varix post-band ligation.

Human postural sway results in response to audible and infrasound emissions from wind turbines

Fifty healthy adult subjects ages 21–73 years attended to audible and infrasound signals generated from a wind turbine, recorded at 600 m and re-created in the laboratory. Stimuli consisted of modulated and unmodulated audible sound at 50 dB SPL, as well as recorded and peak-enhanced infrasound at an overall level of approximately 85 dB SPL (peaks up to 95 dB SPL). Participants were tested for their postural stability, detection, and ratings of audible and infrasound emissions from turbines. They also completed pre- and post-testing surveys for symptoms of imbalance. All subjects were blind to the knowledge that the stimuli were recorded from wind turbines. No significant adverse effects from healthy adults have been noted to date. Some individuals reliably indicated detection of infrasound signals. A few participants indicated mild symptoms (a rating of 1 on a scale from 0 to 4) following the test. Testing of patients who report vertigo will begin soon. Detailed results and implications will be discussed.

스마트 디바이스를 활용한 가청, 비가청 신호 기반 피난방향 탐지 기법 연구

스마트 디바이스를 활용한 가청, 비가청 신호 기반 피난방향 탐지 기법 연구

Quantitative Assessment of Peroneal Artery Pressure at the Ankle With Noninvasive Vascular Testing

Although the foot and ankle derives its arterial supply from a combination of the anterior tibial artery (ATA), posterior tibial artery (PTA), and peroneal artery (PA), the focus of clinical examination techniques and noninvasive vascular testing is primarily on the ATA and PTA and not on the PA. The objectives of the present investigation were to evaluate the feasibility of incorporating an assessment of the PA into a noninvasive vascular testing protocol and to collect normative data of pressure measurements of the PA at the ankle. We attempted to locate a Doppler signal of the PA posterior to the lateral malleolus in consecutive patients undergoing our institution's standard protocol for lower extremity noninvasive vascular testing using the ankle-brachial index and photoplethysmography. An audible signal of the PA with an available pressure measurement recording posterior to the lateral malleolus was found in a large majority (92.0%) of the studied legs with peripheral arterial disease. We also found pressure measurements in the PA generally equivalent to that of the ATA and PTA. The mean ± standard deviation systolic pressure of the PA was 130.33 ± 44.74 (range 54 to 255) mm Hg, with a corresponding ankle-brachial index of 0.92. The results of the present investigation provide unique information on a potentially underappreciated aspect of lower extremity vascular anatomy with the potential to affect rearfoot surgical decision making and planning.

Sound attenuation and audibility of fire alarm signal in Korean residential apartment buildings: A case study

With a view to preventing casualties due to fire outbreaks in residential buildings, we investigated the sound attenuation of audible fire-alarm signals in Korean residential apartment buildings and determine an acoustic condition for enhancing the audibility of such signals. Two sets of field measurements were performed, along with theoretical predictions using sound analysis software. In the first set of measurements, in 17 dwelling units, the standardized alarm sound level requirement of 75 dBA could not be achieved in bedrooms with existing alarm devices. In the second set of measurements, with an additional five dwelling units, both the sound attenuation according to the distance between sound sources and bedrooms and the sound insulation performance of bedroom doors were examined. The sound attenuation levels were increased by 0.72 ( R2 = 0.7982) and 0.48 ( R2 = 0.3001) dB m−1 under open- and closed-door conditions, respectively. Further, the bedroom-door sound insulation performance was in the 18- to 23-dB range. Consequently, we have demonstrated that the sound power of a general residential fire alarm must be 98–107.9 dB, depending on the dwelling-unit size and floor-plan type, in order to achieve a bedroom audibility level of 75 dBA.

133 Development of Sound Directivity Control of Audible Traffic Signal

133 Development of Sound Directivity Control of Audible Traffic Signal

Development and Application of BLE-Based Audible Pedestrian Signal (APS) for Intersection Safety Crossing of Blind People

Development and Application of BLE-Based Audible Pedestrian Signal (APS) for Intersection Safety Crossing of Blind People

Role of electromyography endotracheal tube in preventing recurrent laryngeal nerve injury during thyroid surgery: A case reportAirway trauma during difficult intubation… from the frying pan into the fire?

Role of electromyography endotracheal tube in preventing recurrent laryngeal nerve injury during thyroid surgery: A case reportAirway trauma during difficult intubation… from the frying pan into the fire?

Sexual behavior of Anastrepha striata Schiner (Diptera: Tephritidae) under laboratory conditions

Anastrepha striata Schiner is one of the seven species of tephritidae that are economically important in Brazilian fruit growing, which can infest more than 16 families of host plants, mainly the Myrtaceae. The objective was to obtain information on the age of sexual maturation of males and females and to describe their reproductive behavior in the laboratory. Males reached sexual maturity between 12 and 16 days after emergence, in which most individuals were sexually mature at 14 days of age. During this period, the males performed rapid movements of the wings, producing audible signals. After the females were attracted, the males performed several courtship movements. Females reached sexual maturity between 16 and 19 days after emergence, and the majority was sexually mature at 17 days of age. Daily exhibitions of sexual activity occurred between 5 p.m. and 6 p.m. The species A. striata presented a marked pattern of protandry.

Data-Driven Implementation of Alarm Reduction Interventions in a Cardiovascular Surgical ICU

Alarm fatigue in the ICU setting has been well documented in the literature. The ICU's high-intensity environment requires staff's vigilant attention, and distraction from false and non-actionable alarms pulls staff away from important tasks, creates dissatisfaction, and is a potential patient safety risk if alarms are missed or ignored. This project was intended to improve patient safety by optimizing alarm systems in a cardiovascular surgical intensive care unit (CVSICU). Specific aims were to examine nurses' attitudes toward clinical alarm signals, assess nurses' ability to discriminate audible alarm signals, and implement a bundled set of best practices for monitor alarm reduction without undermining patient safety. CVSICU nurses completed an alarm perception survey and participated in alarm discriminability testing. Nurse survey data and baseline monitor alarm data were used to select targeted alarm reduction interventions, which were progressively phased in. Monitor alarm data and cardiorespiratory event data were trended over one year. Five of the most frequent CVSICU monitor alarm types-pulse oximetry, heart rate, systolic and diastolic blood pressure, pulse oximetry sensor, and ventricular tachycardia > 2-were targeted. After implementation, there was a 61% reduction in average alarms per monitored bed and a downward trend in cardiorespiratory events. To reduce alarm fatigue it is important to decrease alarm burden through targeted interventions. Methods to reduce non-actionable alarms include adding short delays to allow alarm self-correction, adjusting default alarm threshold limits, providing alarm notification through a secondary device, and teaching staff to optimize alarm settings for individual patients.

Detection and localization of whale vocalizations in archived data of seafloor cabled observatories in eastern Japan

Through the examination of archived OBS (Ocean Bottom Seismometer) waveform data of seafloor cabled observatories in the eastern Japan, fin whale vocalizations were detected. Most of those vocalizations were observed with a single OBS because of the sparseness of the OBS deployment. At the observatory off Kushiro-Tokachi in Hokkaido, the fin whale vocalizations were localized using waveform data of both OBS and hydrophone at the same site (Iwase, 2015). At the observatory off Kamaishi in Tohoku District composed of OBSs without a hydrophone, seismic wave velocities in sediment, which are necessary parameters in estimating horizontal range of sound source from apparent emergence angle of transmitted wave at seafloor, were estimated in situ based on air gun signal observation (Iwase, 2016). By using those results, the fin whale vocalizations were localized. At the observatory off Hatsushima Island in Sagami Bay, sperm whale vocalizations were detected in the audible sound signals of a single hydrophone which were recorded on the soundtrack of video tapes with seafloor images. To date, more than 7000 video tapes recorded since 1993 have been archived, and the result of analysis in progress will be shown at the presentation.

Performance Evaluation of 3D-Position Estimation Systems

Applications that are based on indoor location awareness have different requirements with regard to the accuracy of the estimated positions, the measurement cycle time, and the (end-to-end) delay between the start of a measurement and the availability of the position result. Moreover, the energy consumption of the mobile tags is a key parameter for the selection of an appropriate system. In this paper, we present the results of a series of real-time 3D-position measurements carried out with three respective systems. The two commercial systems, DecaWave DW1000 and Time Domain P410, are based on radio-frequency measurements, while an acoustic prototype system employs time-of-flight measurements based on audible signals. The systems were tested in stationary as well as in dynamic scenarios. Our results provide the accuracies and precisions of the individual systems, the position update rates, and the end-to-end delays. In additional measurements, we determined the individual tag power consumptions and calculated a figure of merit giving the energy consumption per position measurement.

Robustness against distortion of fundamental frequency cues in simulated electro-acoustic hearing.

Speech recognition by cochlear implant users can be improved by adding an audible low frequency acoustic signal to electrical hearing; the resulting improvement is deemed "electro-acoustic stimulation (EAS) benefit." However, a crucial low frequency cue, fundamental frequency (F0), can be distorted via the impaired auditory system. In order to understand how F0 distortions may affect EAS benefit, normal-hearing listeners were presented monaurally with vocoded speech (frequencies >250 Hz) and an acoustical signal (frequencies <250 Hz) with differing manipulations of the F0 signal, specifically: a pure tone with the correct mean F0 but with smaller variations around this mean, or a narrowband of white noise centered around F0, at varying bandwidths; a pure tone down-shifted in frequency by 50 Hz but keeping overall frequency modulations. Speech-recognition thresholds improved when tones with reduced frequency modulation were presented, and improved significantly for noise bands maintaining F0 information. A down-shifted tone, or only a tone to indicate voicing, showed no EAS benefit. These results confirm that the presence of the target's F0 is beneficial for EAS hearing in a noisy environment, and they indicate that the benefit is robust to F0 distortion, as long as the mean F0 and frequency modulations of F0 are preserved.

Sensation in the urethra during voiding studied in young healthy men

Objectives: Evaluate sensation in the urethra during voiding and the possible role of visual and audible impulses, in young healthy men.Methods: In 10 healthy volunteers, 2 non-invasive uroflowmetries were done at desire to void and sensations felt during voiding were evaluated by questionnaire. Influence of visual and audible input was studied by performing a uroflowmetry while wearing blindfold eye patches and ear cups + earplugs.Results: All participants reported sensation of start of voiding, all but one of voiding stop. All felt clearly urine passage in the urethra and 8 had a sensation of warmth in the urethra. Visual and audible blocking gave lowering in grades of sensation. To start voiding took a significantly longer time. It became difficult for some men to determine accurately when the flow stopped.Conclusions: Voiding elicited different types of sensation in the urethra in healthy young men. The sensation was independent of the uroflowmetry parameters. Blocking visual and audible signals influenced the sensory and voiding process.

Suspected anaphylaxis from intravenous cefazolin during general anaesthesia in a dog

A six‐year‐old female Shetland Sheepdog with a history of cardiorespiratory compromise during general anaesthesia was referred for ovariohysterectomy surgery. Clinical examination was unremarkable at presentation and physiological parameters under general anaesthesia were within expected ranges during preparation for surgery. Shortly after injecting intravenous cefazolin, the audible signal from the Doppler ultrasound unit stopped. Rapid survey of the patient revealed tachycardia with weak femoral pulses, tachypnoea, hyperpnoea and substantially increased resistance to manual positive pressure ventilation. Stopping inhalant anaesthesia, administering salbutamol, corticosteroids and diphenhydramine were associated with resolution of clinical signs. However, marked hypotension and resistance to ventilation recurred approximately 25 minutes later. Low dose intravenous adrenaline (5 mcg/kg) was effective at increasing arterial blood pressure and reversing respiratory dysfunction. Surgery was completed and the patient recovered uneventfully. Initial reliance on second‐line therapy and delay in administering adrenaline, the recommended treatment for anaphylaxis, may have slowed resolution of clinical signs.

Ānāpāna: Neuro-engineering of Mindfulness

Meditation benefits have been widely supported by many research works. It is considered a natural way of reducing stress, depression, and other anxiety disorders. However, meditation process is a breathe pursuing task that requires long time training to avoid the so-called mind wandering. In this work, we propose a neural-feedback system that detects when mind wanders and generates an audible signal, this way patient’s attention is recovered back again. Finally, we support our approach by testing the system on novice and advanced meditators.