Tropicalizing the Portable Radio: Electronics and the U.S. Military's Battle against Fungi in the Pacific War.

As the U.S. military became embroiled in "jungle warfare" across the Pacific during World War II, it was caught off guard by the rapid deterioration of materials and equipment in the tropics, where the air was hot, humid, and teeming with fungal spores. This article tells the story of how American scientists and engineers understood the "tropical deterioration" of portable radios and electronics and developed techniques to counteract it. Examining scientific efforts to prevent tropical decay reveals how exposure to tropical conditions during World War II shaped the development of portable electronics. Contributing to envirotech history and environmental media studies, this article uncovers the importance of climate proofing to the history of electronics miniaturization. Tropical deterioration, furthermore, provides a technology-focused lens for enriching our historical understanding of the tropics as an environmental imaginary.

Medos, desejos e preocupações acerca da sindemia de Covid-19 e sofrimento psíquico: experiências extensionistas no sul da Bahia, Brasil / Fears, desires and concerns surrounding the Covid-19 syndemic and psychic suffering: university outreach experiences in the south of Bahia, Brazil / Miedos, deseos y preocupaciones sobre la sindemia de Covid-19 y sufrimiento psíquico: experiencias extensionistas en el sur de Bahia, Brasil

Este artigo analisa as relações entre políticas públicas de enfrentamento da Covid-19, desinformação da população e sofrimento psíquico por meio da integração de resultados de duas experiências extensionistas ocorridas no mesmo território e mesmo período de tempo: "Tira dúvidas sobre a Covid" (TDC), programa de rádio que respondia a perguntas dos ouvintes; e "Plantão Psicológico On-line" (PPO), que tem oferecido atendimento emergencial durante a pandemia. Foi realizada análise qualiquantitativa de perguntas direcionadas por ouvintes ao quadro radiofônico e de preocupações sobre a pandemia manifestadas por usuários do PPO no formulário de inscrição para o atendimento. Concluiu-se que a desinformação agravou o contexto de crise, não apenas ampliando as infecções e os óbitos, mas elevando também o sofrimento psíquico. A propagação de notícias falsas e o aumento de problemas de Saúde Mental durante a pandemia são, pois, faces do mesmo fenômeno complexo.(AU)

This article analyzes the relationship between Covid-19 response policies, disinformation and psychic suffering drawing on the results of two university outreach experiences conducted in the same region during the same period: "Answering Questions about Covid" (TDC), a radio program answering listeners queries; and the "On-line Counselling Service" (PPO), offering emergency therapy during the pandemic. We performed a quali-quantitative analysis of listeners' questions and concerns about the pandemic raised by PPO users on the counselling application form. It is concluded that disinformation aggravated the context of the crisis, leading to a rise in infections, deaths and psychic suffering. The spread of fake news and increase in mental health problems are therefore facets of the same complex phenomenon.(AU)

Este artículo analiza las relaciones entre políticas públicas de enfrentamiento de la Covid-19, desinformación de la población y sufrimiento psíquico a partir de la integración de resultados de dos experiencias extensionistas ocurridas en el mismo territorio y período de tiempo: "Solución de dudas sobre Covid ("Tira dúvidas sobre a Covid-TDC"), programa de radio que respondía a preguntas de los oyentes y "Guardia Psicológica On-line" ("Plantão Psicológico On-line-PPO"), que han ofrecido atención de emergencia durante la pandemia. Se realizó un análisis cuali- cuantitativo de preguntas dirigidas por oyentes al programa de radio y de preocupaciones sobre la pandemia manifestadas por usuarios del PPO en el formulario de inscripción para la atención. Se concluyó que la desinformación agravó el contexto de crisis, no solo ampliando las infecciones y los fallecimientos, sino aumentando también el sufrimiento psíquico. La propagación de noticias falsas y el aumento de problemas de salud mental durante la pandemia son, por lo tanto, caras del mismo fenómeno complejo.(AU)

Joint resource optimization in spectrum sharing decode and forward relaying networks.

This paper proposes an adaptive power allocation and subcarrier pairing algorithm for orthogonal frequency division multiplexing based decode and forward cognitive radio networks, where primary and secondary users achieve spectrum sharing in the same frequency band. The secondary network tries to maximize its sum rate while ensuring that the interference introduced to the primary network is below an acceptable level. Although similar problems have been investigated in traditional cooperative communication networks, it's still an open issue in cognitive radio networks due to interference thresholds. The power consumed by the secondary network is not only limited by its own power peak, but also by the interference threshold of the primary user. Our proposed algorithm not only allocates power and pairs subcarriers reasonably, but also specifies the conditions under which the relaying link is superior to the direct transmission. Simulation results show that the sum rate of the proposed algorithm exceeds other methods and obtains a significant performance gain.

Taller de radio: una experiencia a viva voz

El presente trabajo tiene como objetivo realizar un análisis y dar cuenta de las distintas actividades e intervenciones desplegadas en el taller de radio perteneciente al dispositivo de hospital de día. Para tal fin se utilizan fragmentos de la obra de Freud y Lacan, así como aportes de autores contemporáneos para llevar adelante una articulación teórico-clínica. La elección del taller como eje del trabajo se debe a la idea de repensar la práctica cotidiana y la posición de los profesionales dentro del dispositivo. (AU)

Application of Digital Radio Mondiale System in Medical Signal Transmission.

In order to study the application of digital radio mondiale (DRM) broadcasting system in medical signal transmission, taking sinusoidal signal as an example, the transmission format is designed, and the data transmission function of the system channel is verified and applied to the transmission of medical information. Taking the traditional electrocardiogram signal and magnetic resonance image as examples, the two kinds of medical information are successfully transmitted according to the appropriate transmission format. As the simplest and easiest to deploy communication mode, the system will provide the fastest and timeliest information and emergency communication function for disaster relief and rescue, which is a practical and valuable application.

The use of the Cochlear Mini Microphone (MM) as a personal radio system (FM) with young children who are deaf.

OBJECTIVES: This paper describes the background, organization and findings of a project undertaken in 2016-2017, to examine the benefits and challenges of the use of the Cochlear Mini Microphone (MM) by the families of pre-school children with cochlear implants on the Nottingham Auditory Implant Programme. METHODS: The experiences and views of 25 families who used the equipment were obtained and analysed. The information informed subsequent advice, patient literature and professional training. RESULTS: The MM was viewed to be of benefit by just under half of the families. The attitudes and technical competence of families and local professionals, alongside the age and lifestyle of the children, were identified as the key factors affecting the amount of use. CONCLUSION: The insights gained into the challenges and benefits of the MM for this population offered explanations for the limited take-up of the equipment and informed ways to encourage appropriate use Discussion: Equipment issued to very young children works best alongside specific advice and training, targeted at both families and local professionals. Despite some technical limitations, the availability of a personal radio system was found to be of benefit by some families. It encouraged consideration by both families and professionals, of the potential benefits of early introduction of a personal radio system into pre-school group activities and educational settings.

A modified artificial neural network based prediction technique for tropospheric radio refractivity.

Radio refractivity plays a significant role in the development and design of radio systems for attaining the best level of performance. Refractivity in the troposphere is one of the features affecting electromagnetic waves, and hence the communication system interrupts. In this work, a modified artificial neural network (ANN) based model is applied to predict the refractivity. The suggested ANN model comprises three modules: the data preparation module, the feature selection module, and the forecast module. The first module applies pre-processing to make the data compatible for the feature selection module. The second module discards irrelevant and redundant data from the input set. The third module uses ANN for prediction. The ANN model applies a sigmoid activation function and a multi-variate auto regressive model to update the weights during the training process. In this work, the refractivity is predicted and estimated based on ten years (2002-2011) of meteorological data, such as the temperature, pressure, and humidity, obtained from the Pakistan Meteorological Department (PMD), Islamabad. The refractivity is estimated using the method suggested by the International Telecommunication Union (ITU). The refractivity is predicted for the year 2012 using the database of the previous ten years, with the help of ANN. The ANN model is implemented in MATLAB. Next, the estimated and predicted refractivity levels are validated against each other. The predicted and actual values (PMD data) of the atmospheric parameters agree with each other well, and demonstrate the accuracy of the proposed ANN method. It was further found that all parameters have a strong relationship with refractivity, in particular the temperature and humidity. The refractivity values are higher during the rainy season owing to a strong association with the relative humidity. Therefore, it is important to properly cater the signal communication system during hot and humid weather. Based on the results, the proposed ANN method can be used to develop a refractivity database, which is highly important in a radio communication system.

Keeping Communications Flowing During Large-scale Disasters: Leveraging Amateur Radio Innovations for Disaster Medicine.

Medical facilities may struggle to maintain effective communications during a major disaster. Natural and man-made disasters threaten connectivity by degrading or crippling Internet, cellular/mobile, and landline telephone services across wide areas. Communications among staff, between facilities, and to resources outside the disaster area may be lost for an extended time. A prototype communications system created by the National Library of Medicine (NLM) provides basic communication services that ensure essential connectivity in the face of widespread infrastructure loss. It leverages amateur radio to provide resilient email service to local users, enabling them to reach intact communications networks outside the disaster zone. Because amateur radio is inexpensive, always available, and sufficiently independent of terrestrial telecommunications infrastructure, it has often augmented telecommunications capabilities of medical facilities. NLM's solution is unique in that it provides end-user to end-user direct email communications, without requiring the intervention of a radio operator in the handling of the messages. Medical staff can exchange email among themselves and with others outside the communications blackout zone. The technology is portable, is deployable on short notice, and can be powered in a variety of ways to adapt to the circumstances of each crisis. (Disaster Med Public Health Preparedness. 2018;12:257-264).

Distracting and risky behaviours while cycling: a comparison of group and non-group riders in Western Australia.

BACKGROUND: Use of mobile phones and portable audio equipment and alcohol are known to negatively affect cycling ability. Evidence suggests that cyclists may be less likely to engage in these behaviours while riding in a group; however, it is unknown whether group riders are also at reduced risk when participating in non-group riding. OBJECTIVE: To examine the association between group riding participation and the use of mobile phones and portable audio equipment and alcohol while non-group riding in Perth, Western Australia. METHODS: A cross-sectional analysis of an online questionnaire was undertaken. Group and exclusive non-group riders were compared and separate binary logistic regression models were used to examine the association between group riding participation and the use of mobile phones and portable audio equipment and alcohol while non-group riding, controlling for gender, age, education and frequency of non-group riding. RESULTS: Participants included 365 cyclists: 187 exclusive non-group riders (51.2%) and 178 group riders (48.8%). Group riders were less likely to have possibly cycled while over the legal blood alcohol limit in the past 12 months (OR: 0.56, 95% CI 0.34 to 0.92) and were less likely to ever use portable audio equipment (OR: 0.57, 95% CI 0.34 to 0.94) than exclusive non-group riders, while participating in non-group riding. Group riding status was not associated with mobile phone use. CONCLUSIONS: This study provides early evidence that there may be differences between group and non-group riders that impact on their safety behaviours while participating in non-group riding.

A Glucose Sensing System Based on Transmission Measurements at Millimetre Waves using Micro strip Patch Antennas.

We present a sensing system operating at millimetre (mm) waves in transmission mode that can measure glucose level changes based on the complex permittivity changes across the signal path. The permittivity of a sample can change significantly as the concentration of one of its substances varies: for example, blood permittivity depends on the blood glucose levels. The proposed sensing system uses two facing microstrip patch antennas operating at 60 GHz, which are placed across interrogated samples. The measured transmission coefficient depends on the permittivity change along the signal path, which can be correlated to the change in concentration of a substance. Along with theoretical estimations, we experimentally demonstrate the sensing performance of the system using controlled laboratory samples, such as water-based glucose-loaded liquid samples. We also present results of successful glucose spike detection in humans during an in-vivo Intravenous Glucose Tolerance Test (IVGTT). The system could eventually be developed into a non-invasive glucose monitor for continuous monitoring of glucose levels for people living with diabetes, as it can detect as small as 1.33 mmol/l (0.025 wt%) glucose concentrations in the controlled water-based samples satisfactorily, which is well below the typical human glucose levels of 4 mmol/l.

Overload Control for Signaling Congestion of Machine Type Communications in 3GPP Networks.

Because of the limited resources on radio access channels of third generation partnership projection (3GPP) network, one of the most challenging tasks posted by 3GPP cellular-based machine type communications (MTC) is congestion due to massive requests for connection to radio access network (RAN). In this paper, an overload control algorithm in 3GPP RAN is proposed, which proactively disperses the simultaneous access attempts in evenly distributed time window. Through periodic reservation strategy, massive access requests of MTC devices are dispersed in time, which reduces the probability of confliction of signaling. By the compensation and prediction mechanism, each device can communicate with MTC server with dynamic load of air interface. Numerical results prove that proposed method makes MTC applications friendly to 3GPP cellular network.

A Lightweight Radio Propagation Model for Vehicular Communication in Road Tunnels.

Radio propagation models (RPMs) are generally employed in Vehicular Ad Hoc Networks (VANETs) to predict path loss in multiple operating environments (e.g. modern road infrastructure such as flyovers, underpasses and road tunnels). For example, different RPMs have been developed to predict propagation behaviour in road tunnels. However, most existing RPMs for road tunnels are computationally complex and are based on field measurements in frequency band not suitable for VANET deployment. Furthermore, in tunnel applications, consequences of moving radio obstacles, such as large buses and delivery trucks, are generally not considered in existing RPMs. This paper proposes a computationally inexpensive RPM with minimal set of parameters to predict path loss in an acceptable range for road tunnels. The proposed RPM utilizes geometric properties of the tunnel, such as height and width along with the distance between sender and receiver, to predict the path loss. The proposed RPM also considers the additional attenuation caused by the moving radio obstacles in road tunnels, while requiring a negligible overhead in terms of computational complexity. To demonstrate the utility of our proposed RPM, we conduct a comparative summary and evaluate its performance. Specifically, an extensive data gathering campaign is carried out in order to evaluate the proposed RPM. The field measurements use the 5 GHz frequency band, which is suitable for vehicular communication. The results demonstrate that a close match exists between the predicted values and measured values of path loss. In particular, an average accuracy of 94% is found with R2 = 0.86.

Avalanche Survival After Rescue With the RECCO Rescue System: A Case Report.

We report a case of survival of a completely buried avalanche victim after being located with the radar-based RECCO Rescue System. In the winter of 2015, 2 off-piste skiers were completely buried in an avalanche near the secured ski area in Baqueira Beret, Spain. The first victim was located with the RECCO Rescue System in less than 35 minutes and was alive and conscious at extrication. This system emits radio waves and requires a specific reflector. It is a portable device that is used by more than 600 rescue organizations worldwide, especially in secured ski areas. The device should be brought to the avalanche site together with electronic avalanche transceivers, a probing team, and avalanche dogs. In the hands of experienced professionals, the device may allow rapid location of victims not carrying an electronic avalanche transceiver. Although it is not the first successful extrication of a victim with the RECCO Rescue System, it is the first case published in the medical literature and is intended to encourage data collection and to increase our understanding of the effectiveness of this device in avalanche rescue.

"To silence the deafening silence": Survivor's needs and experiences of the impact of disaster radio for their recovery after a natural disaster.

In the aftermath of the Haiyan typhoon, disaster radio was used to spread information and music to the affected population. The study described survivors' experiences of being in the immediate aftermath of a natural disaster and the impact disaster radio made on recovery from the perspective of the individuals affected. Twenty eight survivors were interviewed in focus groups and individual interviews analyzed with phenomenological-hermeneutic method. Being in disaster mode included physical and psychosocial dimensions of being in the immediate aftermath of the disaster. Several needs among the survivors were expressed. Disaster radio contributed to recovery by providing facts and information that helped the survivor to understand and adapt. The music played contributed to emotional endurance and reduced feelings of loneliness. To re-establish social contacts, other interventions are needed. Disaster radio is a positive contribution to the promotion of survivors' recovery after disasters involving a large number of affected people and severely damaged infrastructure. Further studies on the use and impact of disaster radio are needed.

Using Trust to Establish a Secure Routing Model in Cognitive Radio Network.

Specific to the selective forwarding attack on routing in cognitive radio network, this paper proposes a trust-based secure routing model. Through monitoring nodes' forwarding behaviors, trusts of nodes are constructed to identify malicious nodes. In consideration of that routing selection-based model must be closely collaborative with spectrum allocation, a route request piggybacking available spectrum opportunities is sent to non-malicious nodes. In the routing decision phase, nodes' trusts are used to construct available path trusts and delay measurement is combined for making routing decisions. At the same time, according to the trust classification, different responses are made specific to their service requests. By adopting stricter punishment on malicious behaviors from non-trusted nodes, the cooperation of nodes in routing can be stimulated. Simulation results and analysis indicate that this model has good performance in network throughput and end-to-end delay under the selective forwarding attack.

Occupational exposure of personnel operating military radio equipment: measurements and simulation.

Technical literature provides numerous studies concerning radiofrequency exposure measurements for various radio communication devices, but there are few studies related to exposure of personnel operating military radio equipment. In order to evaluate exposure and identify cases when safety requirements are not entirely met, both measurements and simulations are needed for accurate results. Moreover, given the technical characteristics of the radio devices used in the military, personnel mainly operate in the near-field region so both measurements and simulation becomes more complex. Measurements were made in situ using a broadband personal exposimeter equipped with two isotropic probes for both electric and magnetic components of the field. The experiment was designed for three different operating frequencies of the same radio equipment, while simulations were made in FEKO software using hybrid numerical methods to solve complex electromagnetic field problems. The paper aims to discuss the comparative results of the measurements and simulation, as well as comparing them to reference levels specified in military or civilian radiofrequency exposure standards.

Electromagnetic interference from electronic devices used in the management of type 1 diabetes can impair the performance of an avalanche transceiver in search mode.

OBJECTIVE: Portable electronic devices play an important role in the management of type 1 diabetes mellitus. Electromagnetic interference from electronic devices has been shown to impair the function of an avalanche transceiver in search mode (but not in transmitting mode). This study investigates the influence of electromagnetic interference from diabetes devices on a searching avalanche beacon. METHODS: The greatest distance at which an avalanche transceiver (in search mode) could accurately indicate the location of a transmitting transceiver was assessed when portable electronic devices (including an insulin pump and commonly used real-time continuous subcutaneous glucose monitoring system [rtCGMS]) were held in close proximity to each transceiver. RESULTS: The searching transceiver could accurately locate a transmitted signal at a distance of 30 m when used alone. This distance was unchanged by the Dexcom G4 rtCGMS, but was reduced to 10 m when the Medtronic Guardian rtCGMS was held close (within 30 cm) to the receiving beacon. Interference from the Animas Vibe insulin pump reduced this distance to 5 m, impairing the searching transceiver in a manner identical to the effect of a cell phone. CONCLUSIONS: Electromagnetic interference produced by some diabetes devices when held within 30 cm of a searching avalanche transceiver can impair the ability to locate a signal. Such interference could significantly compromise the outcome of a companion rescue scenario. Further investigation using other pumps and rtCGMS devices is required to evaluate all available diabetes electronics. Meantime, all electronic diabetes devices including rtCGMS and insulin pumps should not be used within 30 cm of an avalanche transceiver.

An energy-efficient and compact clustering scheme with temporary support nodes for cognitive radio sensor networks.

A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members.

50 MHz-10 GHz low-power resistive feedback current-reuse mixer with inductive peaking for cognitive radio receiver.

A low-power wideband mixer is designed and implemented in 0.13 µm standard CMOS technology based on resistive feedback current-reuse (RFCR) configuration for the application of cognitive radio receiver. The proposed RFCR architecture incorporates an inductive peaking technique to compensate for gain roll-off at high frequency while enhancing the bandwidth. A complementary current-reuse technique is used between transconductance and IF stages to boost the conversion gain without additional power consumption by reusing the DC bias current of the LO stage. This downconversion double-balanced mixer exhibits a high and flat conversion gain (CG) of 14.9 ± 1.4 dB and a noise figure (NF) better than 12.8 dB. The maximum input 1-dB compression point (P1dB) and maximum input third-order intercept point (IIP3) are -13.6 dBm and -4.5 dBm, respectively, over the desired frequency ranging from 50 MHz to 10 GHz. The proposed circuit operates down to a supply headroom of 1 V with a low-power consumption of 3.5 mW.

Design and optimization of LTE 1800 MIMO antenna.

A multiple input and multiple output (MIMO) antenna that comprises a printed microstrip antenna and a printed double-L sleeve monopole antenna for LTE 1800 wireless application is presented. The printed double-L sleeve monopole antenna is fed by a 50 ohm coplanar waveguide (CPW). A novel T-shaped microstrip feedline printed on the other side of the PCB is used to excite the waveguide's outer shell. Isolation characteristics better than -15 dB can be obtained for the proposed MIMO antenna. The proposed antenna can operate in LTE 1800 (1710 MHz-1880 MHz). This antenna exhibits omnidirectional characteristics. The efficiency of the antenna is greater than 70% and has high gain of 2.18 dBi.