Impact of a bone conduction communication channel on multichannel communication system effectiveness

OBJECTIVE

In this study, the impact of including a bone conduction transducer in a three-channel spatialized communication system was investigated.

BACKGROUND

Several military and security forces situations require concurrent listening to three or more radio channels. In such radio systems, spatial separation between three concurrent radio channels can be achieved by delivering separate signals to the left and right earphone independently and both earphones simultaneously. This method appears to be effective; however, the use of bone conduction as one channel may provide both operational and performance benefits.

METHOD

Three three-channel communication systems were used to collect speech intelligibility data from 18 listeners (System I, three loudspeakers; System 2, stereo headphones; System 3, stereo headphones and a bone conduction vibrator). Each channel presented signals perceived to originate from separate locations. Volunteers listened to three sets of competing sentences and identified a number, color, and object spoken in the target sentence. Each listener participated in three trials (one per system). Each trial consisted of 48 competing sentence sets.

RESULTS

Systems 2 and 3 were more intelligible than System I. Systems 2 and 3 were overall equally intelligible; however, the intelligibility of all three channels was significantly more balanced in System 3.

CONCLUSION

Replacing an air conduction transducer with a bone conduction transducer in a multichannel audio device can provide a more effective and balanced simultaneous monitoring auditory environment.

APPLICATION

These results have important design and implementation implications for spatial auditory communication equipment.

Enhancing community knowledge and health behaviors to eliminate blinding trachoma in Mali using radio messaging as a strategy

The National Blindness Prevention Program in Mali has broadcast messages on the radio about trachoma as part of the country's trachoma elimination strategy since 2008. In 2011, a radio impact survey using multi-stage cluster sampling was conducted in the regions of Kayes and Segou to assess radio listening habits, coverage of the broadcasts, community knowledge and behavior specific to trachoma and facial cleanliness of children. Radio access and listening were high, with 60% of respondents having heard a message on the radio about trachoma. The majority of respondents knew about trachoma, its root causes, its impact on health and prevention measures. Additionally, 66% reported washing their children's faces more than or equal to twice/day and 94% reported latrine disposal of feces. A high percentage of persons who gave a positive response to knowledge and behavior questions reported hearing the trachoma messages on the radio with 60% reporting that the radio is where they learned about trachoma. There was no significant difference in facial cleanliness when comparing children whose primary caregiver had/had not heard the trachoma messages. Next steps include revising the current messages to include more focused behavior change messaging and to engage in a more robust use of community radios.

Acoustic changes of the voice as signs of vocal fatigue in radio broadcasters: preliminary findings

INTRODUCTION AND OBJECTIVES

Vocal fatigue is one of the most common voice symptoms. It usually refers to the sensation of vocal tiredness after a long period of speaking or singing. The purpose of this study was to compare the acoustic characteristics of the voice before and after a long period of voice use in a group of radio broadcasters.

METHODS

Eight radio broadcasters with normal voices were assessed. We used cepstrum, energy ratio, noise to harmonic ratio and soft phonation index as acoustic variables to assess the possible pre-post vocal loading changes objectively.

RESULTS

There were no statistically significant pre-post differences in any of the acoustic parameters. Although cepstrum at high pitch did not show a significant difference, it obtained the greatest difference among the acoustic variables.

CONCLUSIONS

The acoustic measurements used in the present study might not be sensitive enough or appropriate for detecting vocal changes after a long period of voice use, whether in reading (as reported in previous research) or speaking tasks. Moreover, a longer period of vocal loading would eventually reveal more evident and consistent acoustic voice changes.

Measurement of knee flexion/extension angle using wearable UWB radios

This paper proposes a wearable system using UWB transceivers to measure the knee flexion/extension angle parameter, who is known to be of clinical importance. First, a pair of very small and light antennas is placed on the adjacent segments of knee joint. Then, the range data between these two antennas is acquired using Time of Arrival (TOA) estimator. We further use the measured distance to compute the flexion/extension angle using the law of cosines. The performance of the method was compared with a flexible goniometer by simultaneously measuring knee flexion-extension angle. The experimental results show that the system has reasonable performance and has sufficient accuracy for clinical applications.

Acoustic correlates of emphatic stress in Central Catalan

A common feature of public speech in Catalan is the placement of prominence on lexically unstressed syllables ("emphatic stress"). This paper presents an acoustic study of radio speech data. Instances of emphatic stress were perceptually identified. Within-word comparison between vowels with emphatic stress and vowels with primary lexical stress reveals that the former are characterized by having a high tone, higher F0 scaling, and greater intensity, but shorter duration with respect to lexically stressed vowels. Emphatic stress can thus be characterized as anchoring an intonational pitch accent on a lexically unstressed syllable. When this phenomenon occurs, primary lexical stress is still cued by duration. Compared with other lexically unstressed vowels, vowels with emphatic stress have greater duration and intensity, and less vowel centralization. Thus, vowels are hyperarticulated when bearing emphatic stress. In particular, schwa is more open, without merging with /a/. Regarding the distribution of emphatic stresses, the most common pattern observed is binary or rhythmic (les institucions 'the institutions'), with emphatic stress occurring two syllables before the primary stress. Less frequently, emphatic stress appears on the first syllable of the prosodic word (nacionalitats 'nationalities'), occasionally producing stress clash (el marc 'the framework').

Prosodic evaluation of accent distributions in spoken news bulletins of Flemish newsreaders

The current article describes research on whether the goodness of a particular speaking style correlates with the way speakers distribute pitch accents in their speech. Study 1 analyzed two Flemish newsreaders, who, according to poll ratings, had previously been judged to represent a good vs bad speaker. A perception study in which participants had to assess the quality of spoken paragraphs produced by either of the two speakers confirmed that one speaker was rated as significantly and consistently better than the other one. An exploration of the accent distributions in those paragraphs showed that the accent distributions of the better speaker were more similar to the ones of a gold standard, i.e., the accent distributions as predicted by two independent intonation experts. Study 2 compared synthetic versions of a selection of the paragraphs of study 1, generated by a Dutch text-to-speech system. It compared three basically identical versions of the texts, except that they had different accent distributions according to the gold standard, or to distributions as observed in the productions of the two newsreaders. A perception study revealed that the versions of the bad speaker were rated as being significantly worse than the other versions. The two studies thus show that variation in accent distribution can indeed affect the way spoken texts are assessed in terms of their perceived quality.

Care to be a nurse? Reflections on a radio broadcast and its ramifications for nursing today

Nursing education in the UK has lagged behind most of the developed world since inception of Project 2000 because in England, a diploma has been accepted as the basis for education, unlike other countries (including Scotland and Wales) a degree has been the accepted standard for many years. While Australia's nursing education has been more protected, an anti-intellectualism is creeping in with a technical college now offering a nursing degree, and some universities lowering their admission standards for nursing courses. Changes in the UK being imposed through the influence of the global financial crisis threaten nursing even further and this is not helped by short sighted media reports of problems with nursing care in the National Health Service. This paper examines the continuing devaluing of critical thinking, something that we contend, with the strongest emphasis, should be at the core of every aspect of nursing practice, education and research., and implications for nursing in both the UK and Australia.

Effects of the Gama Cuulu radio serial drama on HIV-related behavior change in Zambia

The Gama Cuulu radio serial drama is written and produced in Zambia's Southern Province. It promotes behavior change and service use to prevent HIV transmission. The authors evaluated the effects of Gama Cuulu on intermediate outcomes (e.g., perceived norms), as well as number of sexual partners, condom use, and HIV testing in the past year among adults between 18 and 49 years of age. The authors used a pretest/posttest assessment with a comparison group design, with Southern Province as the intervention area and Western Province as the comparison area. Approximately 1,500 in-person interviews were conducted in both provinces in 2006 (pretest), 2007, and 2008. Regression models included terms for province, time, and the interaction of the two. Outcomes improved in both provinces (e.g., by 2008, 37.6% of participants in Southern Province and 28.3% participants in Western Province tested for HIV in the past year). Pretest-to-posttest changes in condom use (from 20.2% to 29.4% in Southern Province) and 5 intermediate outcomes were significantly different in the 2 provinces. However, changes in condom use were not associated with listening to Gama Cuulu and changes in other outcomes were similar in both provinces. Weak intervention effects might be attributable to implementation challenges or the saturation of HIV programs in Zambia.

Post-coma persons emerged from a minimally conscious state and showing multiple disabilities learn to manage a radio-listening activity

This study assessed microswitch-based technology to enable three post-coma adults, who had emerged from a minimally conscious state but presented motor and communication disabilities, to operate a radio device. The material involved a modified radio device, a microprocessor-based electronic control unit, a personal microswitch, and an amplified MP3 player. The study was carried out according to a non-concurrent multiple baseline design across participants. During the intervention, all three participants learned to operate the radio device, changing stations and tuning on some of them longer amounts of time than on others (i.e., suggesting preferences among the topics covered by those stations). They also ended a number of sessions before the maximum length of time allowed for them had elapsed. The practical (rehabilitation) implications of the findings were discussed.

Tobacco in the news: associations between news coverage, news recall and smoking-related outcomes in a sample of Australian smokers and recent quitters

This paper aims to track smokers' and recent quitters' recall of tobacco news, compare patterns of recall with patterns of news coverage and assess associations between news recall and smoking-related cognitions and behaviours, by using a quantitative analysis. The Cancer Institute New South Wales (NSW)'s Tobacco Tracking Survey, a continuous tracking telephone survey of adult smokers and recent quitters, was used to monitor recall of tobacco news and smoking-related cognitions and behaviours from January to September 2010 (approximately 50 interviews per week; n = 1952). Thirty per cent of respondents reported semi-prompted recall of tobacco news with patterns of recall closely following peaks in news coverage. Television was the most frequently cited source of tobacco news. Multivariate logistic regression analyses indicated that, controlling for individual characteristics, smokers with high levels of tobacco news recall were significantly more likely to have strong beliefs about harms from smoking [odds ratio (OR) = 1.38] and frequent thoughts about quitting (OR = 1.32). The results show that the news media are an important source of information for smokers, with the potential to influence beliefs and to put or keep quitting on the smokers' agenda. Media advocacy remains an important component of tobacco control.

Two applications of time reversal mirrors: seismic radio and seismic radar

Two seismic applications of time reversal mirrors (TRMs) are introduced and tested with field experiments. The first one is sending, receiving, and decoding coded messages similar to a radio except seismic waves are used. The second one is, similar to radar surveillance, detecting and tracking a moving object(s) in a remote area, including the determination of the objects speed of movement. Both applications require the prior recording of calibration Green's functions in the area of interest. This reference Green's function will be used as a codebook to decrypt the coded message in the first application and as a moving sensor for the second application. Field tests show that seismic radar can detect the moving coordinates (x(t), y(t), z(t)) of a person running through a calibration site. This information also allows for a calculation of his velocity as a function of location. Results with the seismic radio are successful in seismically detecting and decoding coded pulses produced by a hammer. Both seismic radio and radar are highly robust to signals in high noise environments due to the super-stacking property of TRMs.

Facilitating disaster preparedness through local radio broadcasting

The 2008 Disaster Mitigation Preparedness (DMP) study took place in Aceh province, Indonesia. It sought to help develop radio programmes and messages to increase resilience to disasters. The role of radio was evaluated during and after the 2004 Asian tsunami disaster. The study team interviewed 984 tsunami survivors from nine sub-districts of Banda Aceh, and local nongovernmental organisations convened eight focus groups around the area of Aceh Besar. Six key informant interviews were held with government disaster management agencies. The DMP survey is the first of its kind to interview a representative random sample of Banda Aceh residents. It reveals the importance of community and social networks, during disaster situations, when essential communications are down. A disaster warning information system based on a multi-media approach needs to be developed. The wider community should be involved in the planning, education and training of Banda Aceh and Aceh Besar residents to facilitate appropriate personal and community survival strategies.

Post-coma persons with extensive multiple disabilities use microswitch technology to access selected stimulus events or operate a radio device

The present two studies extended research evidence on the use of microswitch technology by post-coma persons with multiple disabilities. Specifically, Study I examined whether three adults with a diagnosis of minimally conscious state and multiple disabilities could use microswitches as tools to access brief, selected stimulus events. Study II assessed whether an adult, who had emerged from a minimally conscious state but was affected by multiple disabilities, could manage the use of a radio device via a microswitch-aided program. Results showed that the participants of Study I had a significant increase of microswitch responding during the intervention phases. The participant of Study II learned to change radio stations and seemed to spend different amounts of session time on the different stations available (suggesting preferences among the programs characterizing them). The importance of microswitch technology for assisting post-coma persons with multiple disabilities to positively engage with their environment was discussed.

Knowledge, stigma, and behavioral outcomes among antiretroviral therapy patients exposed to Nalamdana's radio and theater program in Tamil Nadu, India

Arts-based programs have improved HIV-related knowledge, attitudes, and behavior in general and at-risk populations. With HIV transformed into a chronic condition, this study compares patients at consecutive stages of receiving antiretroviral treatment, coinciding with exposure to a radio-and-theater-based educational program (unexposed [N = 120], just exposed [N = 77], Exposed a month ago [N = 60]). Exposure was associated with significantly higher HIV-related knowledge (15-20%, all p < .01), lower levels of stigma (2-7% lower, all p < .10), and over four times the adjusted odds of asking doctors questions about HIV (p = .07). Higher dose of exposure was associated with lower felt stigma (28% reduction per message recalled), greater odds of consistent condom use (adjusted odds ratio [AOR]: 1.12, p = .01), doctor-patient communication (AOR: 1.20, p = .003), peer advice-giving (AOR: 1.18, p = .03) and HIV-related advocacy (AOR: 2.35, p = .07). Similar partnerships between arts-based nongovernmental organizations and government hospitals may improve patient outcomes in HIV treatment settings.

A tennis ball and music as a patients solution for pulsatile tinnitus

We present the case of a 74-year-old man with a pulsatile somatosound causing insomnia and day-time irritation. Given the lack of salvation after medical therapy the patient went in search for a solution and found it in a tennis ball and radio. In this case, the somatosound was due to an extracranial arteriovenous malformation, but the differential diagnosis of pulsatile somatosounds is quit extended, ranging form vascular disorders to tumoral processes. This makes these cases challenging for all caretakers.

A cluster-randomised controlled trial to compare the effectiveness of different knowledge-transfer interventions for rural working equid users in Ethiopia

There have been few studies evaluating the efficacy of knowledge-transfer methods for livestock owners in developing countries, and to the authors' knowledge no published work is available that evaluates the effect of knowledge-transfer interventions on the education of working equid users. A cluster-randomised controlled trial (c-RCT) was used to evaluate and compare the effectiveness of three knowledge-transfer interventions on knowledge-change about equid health amongst rural Ethiopian working equid users. Groups were exposed to either; an audio programme, a village meeting or a diagrammatic handout, all of which addressed identical learning objectives, and were compared to a control group which received no intervention. Thirty-two villages were randomly selected and interventions randomly assigned. All participants in a village received the same intervention. Knowledge levels were assessed by questionnaire administration. Data analysis included comparison of baseline data between intervention groups followed by multilevel linear regression models (allowing for clustering of individuals within village) to evaluate the change in knowledge between the different knowledge-transfer interventions. A total of 516 randomly selected participants completed the pre-intervention questionnaire, 504 of whom undertook the post-dissemination questionnaire, a follow up response rate of 98%. All interventions significantly improved the overall 'change in knowledge' score on the questionnaire compared to the control, with the diagrammatic handout (coefficient (coef) 9.5, S.E.=0.6) and the village meeting (coef 9.7, S.E.=0.6) having a significantly greater impact than the audio programme (coef 4.8, S.E.=0.6). Covariates that were different at baseline, and which were also significant in the final model, were age and pre-intervention score. Although they had a minimal effect on the intervention coefficients there was a significant interaction between age and intervention. This study should aid the design of education materials for adult learning for working equid users and other groups in developing countries.

Effects of a mass media intervention on HIV-related stigma: 'Radio Diaries' program in Malawi

HIV-related stigma has been recognized as a significant public health issue, yet gaps remain in development and evaluation of mass media interventions to reduce stigma. The Malawi 'Radio Diaries' (RD) program features people with HIV telling stories about their everyday lives. This study evaluates the program's effects on stigma and the additional effects of group discussion. Thirty villages with 10 participants each were randomized to listen to RD only, to the program followed by group discussion or to a control program. Post-intervention surveys assessed four stigma outcomes: fear of casual contact, shame, blame and judgment and willingness to disclose HIV status. Regression analyses indicated that fear of casual contact was reduced by the intervention. Shame was reduced by the radio program, but only for those reporting prior exposure to the radio program and for those who did not have a close friend or relative with HIV. Shame was not reduced when the radio program was followed by discussion. The intervention reduced blame for men and not women and for younger participants but not older participants. Including people with HIV/AIDS in mass media interventions has potential to reduce stigma.

Multi-channel multi-radio using 802.11 based media access for sink nodes in wireless sensor networks

The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and data over IP networks instead of standalone video circuits. These systems will increase their reliability in the future on wireless networks and on IEEE 802.11 networks. However, due to limited non-overlapping channels, delay, and congestion there will be problems at sink nodes. In this paper we provide necessary conditions to verify the feasibility of round robin technique in these networks at the sink nodes by using a technique to regulate multi-radio multichannel assignment. We demonstrate through simulations that dynamic channel assignment scheme using multi-radio, and multichannel configuration at a single sink node can perform close to optimal on the average while multiple sink node assignment also performs well. The methods proposed in this paper can be a valuable tool for network designers in planning network deployment and for optimizing different performance objectives.

Bringing text display digital radio to consumers with hearing loss

Radio is migrating to digital transmission, expanding its offerings to include captioning for individuals with hearing loss. Text display radio requires a large amount of word throughput with minimal screen display area, making good user interface design crucial to its success. In two experiments, we presented hearing, hard-of-hearing, and deaf consumers with National Public Radio stories converted to text and examined their preferences for and reactions to midsized and small radio text displays. We focused on physical display attributes such as text color, font style, line length, and scrolling type as well as emergency alert messages and emergency prompts for drivers, announcer identification schemes, and synchronization of audio and text. Results suggest that midsized, Global Positioning System (GPS)-style displays were well liked, synchronization of audio and text was important to comprehension and retrieval of story details, identification of announcers was served best with a combination of name change in parenthesis and color change, and a mixture of color and flashing symbols was preferred for emergency alerting.

Does wearing a surgical facemask or N95-respirator impair radio communication?

PURPOSE

This study evaluated the impact wearing a surgical facemask or N95 air purifying respirator (N95) has on radio reception.

METHODS

We compared the ability of a flight crewmember and a layperson sitting in a Bell 407 crew compartment and a dispatcher sitting in a communication center to accurately record 20 randomized aviation terms transmitted over the radio by a helicopter emergency medical services (HEMS) pilot wearing a surgical facemask and six different N95s with and without the aircraft engine operating.

RESULTS

With the aircraft engine off, all terms (100% accuracy) were correctly identified, regardless of the absence or presence of the surgical facemask or N95 studied. With the aircraft engine on, the surgical facemask (3M-1826) and two N95 respirators (3M-1860, Safe Life Corp-150) maintained 100% accuracy. Remaining N95 accuracy was as follows: 3M-8511 and Kimberly-Clark PFR95 (98%), Inoyel-3212 (97%), and 3M-1870 (93%).

CONCLUSIONS

In general, despite wearing a facemask, radio reception accuracy is high (>90%). However, aircraft engine noise and N95 type do appear to adversely affect the accuracy of radio reception. All HEMS pilots and crewmembers should be aware of these radio reception findings when using an N95 respirator during transport. A brief review of the surgical facemask and N95 effectiveness to prevent viral respiratory infections is provided.

Health promoting community radio in rural Bali: an impact evaluation

INTRODUCTION

This article reports and discusses the process and key recommendations of an evaluation of a community oriented radio station in a rural village in Bali, Indonesia. Community development and health promotion strategies were adopted with the purpose of positively impacting the health and social needs of the local community. The essential element of participation in communication for development was extended to the choice of an evaluation methodology that facilitated community empowerment.

METHODS

The Most Significant Change method was utilised to interview 74 participants (combination of individual interview and focus groups) and to provide the basis for the community itself to identify what it considered to be significant change brought about by the on-air and off-air interventions delivered by the radio station.

RESULTS

The 2007 study found that, in contrast to the findings of a needs assessment in 2004, the community now largely valued the input of the radio station with community members stating they were 'very proud of the radio station'. Changes in community perceptions are considered attributable to the radio station adopting a health promotion/community development approach to a combination of on-air programming to support off-air activities within the community. The radio station is in a valuable position to continue making a positive contribution to the village of Tulikup and to the wider region of Bali.

CONCLUSION

Heartline Bali FM made a positive impact on the quality of life of local people through a combination of strategically designed on- and off-air activities based on a community development and community participation approach to radio programming. Most Significant Change evaluation extended and strengthened the participatory dynamic of the 3 year project.

Infections onboard ship--analysis of 1290 advice calls to the Radio Medical (RM) doctor in Sweden. Results from 1997, 2002, 2007, and 2009

Results from a descriptive study on Swedish Telemedical Advice Services (TMAS) from 1997, 2002, 2007, and the first six months of 2009 on infectious conditions are presented. These findings concern symptoms, actions taken, number of evacuations, means of communication, and use of digital photos. They show that infectious conditions are a significant contributor to calls to the service and that they can be more frequently treated on board than can other conditions.