Articoli di riviste: "Cell phone systems Radio"

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Siebert, Patrick, Mustapha Mouloua, Kendra Burns, Jennifer Marino, Lora Scagliola, Lelah Winters, Peter Hancock e Dan Agliata. "The Effects of Telematics on Driver Distraction". Proceedings of the Human Factors and Ergonomics Society Annual Meeting 46, n. 22 (settembre 2002): 1868–70. http://dx.doi.org/10.1177/154193120204602219.

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This study used both cellular phones and analogue radio to measure driver distraction and workload in a low fidelity driving simulator. Thirty-four participants performed a simulated driving task while using either a cell phone or a radio in conjunction with a secondary task assessing their spare attentional capacity. The results showed that more lane deviations were made during the cell phone and radio tuning use than both of the pre-allocation and Post-allocation phases. The secondary task errors were also higher during both the cell phone and radio tuning allocation phase than the pre-allocation and post-allocation phases. These findings indicate the greater workload load levels associated with the use of telemetric devices. These findings have major implications for driver safety and telemetric systems design.

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Schroeder, J. L., W. S. Burgett, K. B. Haynie, I. Sonmez, G. D. Skwira, A. L. Doggett e J. W. Lipe. "The West Texas Mesonet: A Technical Overview". Journal of Atmospheric and Oceanic Technology 22, n. 2 (1 febbraio 2005): 211–22. http://dx.doi.org/10.1175/jtech-1690.1.

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Abstract The West Texas Mesonet originated in 1999 as a project of Texas Tech University. The mesonet consists of 40 automated surface meteorological stations, two atmospheric profilers, and one upper-air sounding system. Each surface station measures up to 15 meteorological and 10 agricultural parameters over an observation period of 5 and 15 min, respectively. The mesonet uses a combination of radio, cell phone, landline phone, and serial server (Internet) communication systems to relay data back to the base station at Reese Technology Center (formerly Reese Air Force Base), Texas. Data are transmitted through the radio network every 5 min for most meteorological data and every 15 min for agricultural data. For stations located outside of the radio network, phone systems transmit data every 30–60 min. The archive includes data received through the various communication systems, as well as data downloaded in the field from each station during regularly scheduled maintenance visits. Quality assurance/control (QA/QC) tests effectively flag data for manual review from a decision maker. The QA/QC flags and review decisions are then added to the database. All data are available free of charge; real-time data are available on the West Texas Mesonet Web page, and an interface to access the data archive is currently being developed.

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Abdimuratov, Zh S., Zh D. Manbetova, M. N. Imankul, K. S. Chezhimbayeva e A. Zh Sagyndikova. "METHODS FOR PROTECTING THE EQUIPMENT OF CELLULAR (MOBILE) CONNECTION FROM ELECTROMAGNETIC IMPACT". PHYSICO-MATHEMATICAL SERIES 335, n. 1 (10 febbraio 2021): 81–89. http://dx.doi.org/10.32014/2021.2224-5294.12.

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Under electromagnetic impact (EMI) of a sufficient level, temporary disruption of functioning, processing, transmission and storage of information in cellular equipment is possible. Possible problems of electromagnetic compatibility (EMC) of a mobile phone and a base station (BS) of cellular connection under the influence of electromagnetic radiation (EMR) from other sources and their negative impact on functioning are considered. The energy of the HF electromagnetic field (EMF) after passing through the protective case can affect the devices of shielded radio electronic equipment (REE), therefore, the possible negative consequences of the impact of high-energy EMF on the REE are described. Possible negative consequences under certain conditions from the influence of the skin-effect, the effects of electrostatic discharge and electromagnetic pulses on electronic devices are given. It is shown that the constructional method of protecting REE from the effects of external electromagnetic factors consists in reducing the collected and transmitted EMF energy by improving the design, placement and installation of equipment. Components of some vendors for 5G systems that are resistant to external interference are given, and the possibilities for reducing the radiation level of a cell phone are noted. The necessity of an integrated approach to solving EMC problems is substantiated, which consists in the use of structural, circuitry and structural-functional methods of EMC provision. The new 5G (Fifth Generation) standard will operate at higher operating frequencies compared to previous generations. Due to the workload of the electromagnetic spectrum at frequencies below 6 GHz, 5G networks will be based on wireless radio access systems operating at frequencies of 30–100 GHz, that is, in the lower band of the extremely high frequency range EHF (Extremely High Frequency), 30–300 GHz.

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Abdimuratov, Zh S., Zh D. Manbetova, M. N. Imankul, K. S. Chezhimbayeva e A. Zh Sagyndikova. "METHODS FOR PROTECTING THE EQUIPMENT OF CELLULAR (MOBILE) CONNECTION FROM ELECTROMAGNETIC IMPACT". PHYSICO-MATHEMATICAL SERIES 335, n. 1 (8 febbraio 2021): 81–89. http://dx.doi.org/10.32014/2021.2518-1726.12.

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Under electromagnetic impact (EMI) of a sufficient level, temporary disruption of functioning, processing, transmission and storage of information in cellular equipment is possible. Possible problems of electromagnetic compatibility (EMC) of a mobile phone and a base station (BS) of cellular connection under the influence of electromagnetic radiation (EMR) from other sources and their negative impact on functioning are considered. The energy of the HF electromagnetic field (EMF) after passing through the protective case can affect the devices of shielded radio electronic equipment (REE), therefore, the possible negative consequences of the impact of high-energy EMF on the REE are described. Possible negative consequences under certain conditions from the influence of the skin-effect, the effects of electrostatic discharge and electromagnetic pulses on electronic devices are given. It is shown that the constructional method of protecting REE from the effects of external electromagnetic factors consists in reducing the collected and transmitted EMF energy by improving the design, placement and installation of equipment. Components of some vendors for 5G systems that are resistant to external interference are given, and the possibilities for reducing the radiation level of a cell phone are noted. The necessity of an integrated approach to solving EMC problems is substantiated, which consists in the use of structural, circuitry and structural-functional methods of EMC provision. The new 5G (Fifth Generation) standard will operate at higher operating frequencies compared to previous generations. Due to the workload of the electromagnetic spectrum at frequencies below 6 GHz, 5G networks will be based on wireless radio access systems operating at frequencies of 30–100 GHz, that is, in the lower band of the extremely high frequency range EHF (Extremely High Frequency), 30–300 GHz.

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Arigye, Wilford, Mu Zhou, Muhammad Junaid Tahir, Waqas Khalid e Qiaolin Pu. "NNT: Nearest Neighbour Trapezoid Algorithm for IoT WLAN Smart Indoor Localization Leveraging RSSI Height Estimation". Journal of Sensors 2021 (31 luglio 2021): 1–10. http://dx.doi.org/10.1155/2021/1970896.

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Indoor localization as a technique for assisting, or replacing outdoor satellite and cell tower localization systems, has taken a toll in the recent Internet of Things (IoT) era. This IoT drive has prompted increased research towards indoor localization, where fingerprinting, radio mapping as a cost-effective and efficient scheme, is emerging as the best enterprise entrepreneurs choose. However, indoor complex environments comprise of trackable devices (TD) at various heights, such as child trackers, dog tags, TD on the table, TD’s in the pockets, and situations such as pedestrians talking on the phone: that is at the height of the ear, amongst others. This paper first investigates and analyses “experimentally” the impact of received signal strength indicator (RSSI) fingerprinting height to construct radio maps for indoor localization. Secondly, it proposes the novel trapezoid path loss model for RSSI estimation and finally the nearest neighbour trapezoid (NNT) algorithm for IoT smart indoor localization leveraging and mitigating the impact of height considered during the offline signal fingerprinting. We further propose approximately 1 meter above the flooring of the target space as the effective fingerprinting height for indoor localization approaches.

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Parker, R. Stephen, John L. Kent e Karl B. Manrodt. "The usage of mobile communication systems in the trucking industry". Journal of Transportation Management 12, n. 1 (1 aprile 2000): 49–56. http://dx.doi.org/10.22237/jotm/954547500.

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This article reports the findings of a mobile communications survey mailed out to over 2,000 trucking firms. The findings indicate that 68% of respondents use some form of mobile communication system in their firm. Various types of mobile communication systems were reported, including two-way pagers, one-way pagers, cell phones, two-way radio, and satellite communications. Additionally, implementation decision factors for mobile communication systems were evaluated for both users and non-users of mobile communication systems.

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Tyutyunik, Andrey S., Alexey A. Badashev e Vladimir S. Gurchenko. "The problem of increasing the capacity of mobile communication channels and possible solutions". Radioelectronics. Nanosystems. Information Technologies. 13, n. 1 (27 marzo 2021): 95–103. http://dx.doi.org/10.17725/rensit.2021.13.095.

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In this paper the problem of the growing demand for increasing the capacity of communication channels is considered, using the example of real statistical data of the current mobile operator, and the search for possible ways to solve this issue. The analysis of the distribution of electromagnetic fields and SAR for a three-layer model of the human head when interacting with a cell phone is carried out. The results obtained allow us to conclude that it is impossible to significantly increase the capacity of mobile terminals. The increase in power is accompanied by a significant increase in the spatial peak SAR, which exceeds the value recommended by international standards. As an alternative, the main directions and developments for raising the energy potential in the fifth generation 5G cellular radio channels in the millimeter wavelength range have been identified.

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Ogunrinola, Olawale Oluwasegun, Isaiah Opeyemi Olaniyi, Segun A. Afolabi, Gbemiga Abraham Olaniyi e Olushola Emmanuel Ajeigbe. "Modelling and Development of a Radio Resource Control and Scheduling Algorithm for Long-Term Evolution (LTE) Uplink". Review of Computer Engineering Studies 8, n. 2 (30 giugno 2021): 23–34. http://dx.doi.org/10.18280/rces.080201.

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Modern radio communication services transmit signals from an earth station to a high-altitude station, space station or a space radio system via a feeder link while in Global Systems for Mobile Communication (GSM) and computer networks, the radio uplink transmit from cell phones to base station linking the network core to the communication interphase via an upstream facility. Hitherto, the Single-Carrier Frequency Division Multiple Access (SC-FDMA) has been adopted for uplink access in the Long-Term Evolution (LTE) scheme by the 3GPP. In this journal, the LTE uplink radio resource allocation is addressed as an optimization problem, where the desired solution is the mapping of the schedulable UE to schedulable Resource Blocks (RBs) that maximizes the proportional fairness metric. The particle swarm optimization (PSO) has been employed for this research. PSO is an algorithm that is very easy to implement to solve real time optimization problems and has fewer parameters to adjust when compared to other evolutionary algorithms. The proposed scheme was found to outperform the First Maximum Expansion (FME) and Recursive Maximum Expansion (RME) in terms of simulation time and fairness while maintaining the throughput.

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Thrimurthulu, V., e N. S. Murti Sarma. "Investigation on Interference Mitigation Schemes for Next Generation Cellular Communications". International Journal of Engineering & Technology 7, n. 2.20 (18 aprile 2018): 230. http://dx.doi.org/10.14419/ijet.v7i2.20.14768.

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The fanciful quick development and exponential increment of advanced mobile phones the remote info activity request is additional within the returning years. That forces reexamining current remote cell arranges thanks to the shortage of the accessible vary. 2 noteworthy difficulties for advancing future Evolution (LTE) systems area unit to accomplish improved cell scope and framework limit contrasted and broadband Code Division Multiple Access (WCDMA) framework. Powerful use of radio assets and thick vary use is at the middle to realize these objectives. Be that because it might, thick repeat use might increment between cell electric resistance, that so extraordinarily restricts the limit of shoppers within the framework. Between cell obstruction will limit general framework execution as so much as output and preternatural productivity, significantly for the shoppers set at the cell edge region. later on, cautious administration of between cell obstructions finishes up vital to boost LTE framework execution. during this paper, obstruction alleviation plans for LTE downlink systems area unit investigated. The eNB and also the Mobile-Femto as each provide similar assets and transfer speed. This has created AN electric resistance issue from the downlink signs of every alternative to their UEs. this examination has adjusted a adept repeat use conspire that worked powerfully finished separation and accomplished increased outcomes within the flag quality and output of Macro and Mobile-Femto UE once contrasted with past electric resistance administration plans e.g. Partial Frequency use factor1 (NoFFR-3) and uncomplete Frequency use factor3 (FFR-3). Keywords: The fanciful quick development and exponential increment of advanced mobile phones the remote info activity request is additional within the returning years. That forces reexamining current remote cell arranges thanks to the shortage of the accessible vary. 2 noteworthy difficulties for advancing future Evolution (LTE) systems area unit to accomplish improved cell scope and framework limit contrasted and broadband Code Division Multiple Access (WCDMA) framework. Powerful use of radio assets and thick vary use is at the middle to realize these objectives. Be that because it might, thick repeat use might increment between cell electric resistance, that so extraordinarily restricts the limit of shoppers within the framework. Between cell obstruction will limit general framework execution as so much as output and preternatural productivity, significantly for the shoppers set at the cell edge region. later on, cautious administration of between cell obstructions finishes up vital to boost LTE framework execution. during this paper, obstruction alleviation plans for LTE downlink systems area unit investigated. The eNB and also the Mobile-Femto as each provide similar assets and transfer speed. This has created AN electric resistance issue from the downlink signs of every alternative to their UEs. this examination has adjusted a adept repeat use conspire that worked powerfully finished separation and accomplished increased outcomes within the flag quality and output of Macro and Mobile-Femto UE once contrasted with past electric resistance administration plans e.g. Partial Frequency use factor1 (NoFFR-3) and uncomplete Frequency use factor3 (FFR-3).

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Kordzadeh, Atefeh, Dominik Holzmann, Alfred Binder, Thomas Moldaschl, Johannes Sturm e Ali Roshanghias. "Miniaturized On-Chip NFC Antenna versus Screen-Printed Antenna for the Flexible Disposable Sensor Strips". IoT 1, n. 2 (28 ottobre 2020): 309–19. http://dx.doi.org/10.3390/iot1020018.

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With the ongoing trend toward miniaturization via system-on-chip (SoC), both radio-frequency (RF) SoCs and on-chip multi-sensory systems are gaining significance. This paper compares the inductance of a miniaturized on-chip near field communication (NFC) antenna versus the conventional screen-printed on-substrate ones that have been used for the transfer of sensory data from a chip to a cell phone reader. Furthermore, the transferred power efficiency in a coupled NFC system is calculated for various chip coil geometries and the results are compared. The proposed NFC antenna was fabricated via a lithography process for an application-specific integrated circuit (ASIC) chip. The chip had a small area of 2.4 × 2.4 mm2, therefore a miniaturized NFC antenna was designed, whereas the screen-printed on-substrate antennas had an area of 35 × 51 mm2. This paper investigates the effects of different parameters such as conductor thickness and materials, double layering, and employing ferrite layers with different thicknesses on the performance of the on-chip antennas using full-wave simulations. The presence of a ferrite layer to increase the inductance of the antenna and mitigate the interactions with backplates has proven useful. The best performance was obtained via double-layering of the coils, which was similar to on-substrate antennas, while a size reduction of 99.68% was gained. Consequently, the coupling factors and maximum achievable power transmission efficiency of the on-chip antenna and on-substrate antenna were studied and compared.

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Thornton, Jack. "All that Noise". Mechanical Engineering 133, n. 01 (1 gennaio 2011): 34–37. http://dx.doi.org/10.1115/1.2011-jan-3.

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This article describes various sources of noise in computer analysis. Noise is a fact of life and is usually heard as wind, traffic, other creatures, etc. Humans are also surrounded by electromagnetic noise-radio and TV signals, signals from cell phones, and global positioning systems. Noise is also the unwanted data that accompanies all but the simplest measurements. According to experts in the field of digital simulation, noise in data can be costly, in terms of time, money, and error, when it gets into computer analysis of engineering designs. Finding and eliminating noise can make significant hits to engineering schedules, deadlines, and budgets. The costs of wasted time add up quickly at $50 an hour for a designer and $150 an hour or more per staff engineer. Rates for independent experts are two to three times higher. To this must be added the costs of engineering resources wasted, computer systems sidetracked, and deadlines missed.

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Sudo, Noriko, Miyu Urakawa, Nobuyo Tsuboyama-Kasaoka, Kanami Yamada, Yoshiyuki Shimoura e Nobuo Yoshiike. "Local Governments’ Disaster Emergency Communication and Information Collection for Nutrition Assistance". International Journal of Environmental Research and Public Health 16, n. 23 (21 novembre 2019): 4617. http://dx.doi.org/10.3390/ijerph16234617.

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We examined local governments’ disaster emergency communication and information collection and distribution systems. Postal surveys were conducted for all prefectures, cities with public health centers, and specified districts in Tokyo Metropolis in 2005 and 2013. Municipalities were included in the 2013 survey only. The response rate for the 2013 survey was 71.2% (n = 1272). Thirty-six prefectures, 41 cities with health centers, and 16 specified districts in Tokyo Metropolis answered both surveys. A majority of respondents (88.8% in 2005 and 92.1% in 2013) of respondents reported that disaster management radio broadcasting was written into their local disaster management plans, guidelines, or manuals as the main communication tool. The proportion of respondents using computer networks (41.6–60.7%) and cell phones (email) (40.4–62.9%) had significantly increased between the surveys. It was also found that municipalities that had been previously affected by disasters (39.6%) were more likely to have systems to collect information from shelters and affected communities than those without any experience (24.3%), and prefectures that had been previously affected by disasters were more likely to have food supply damage reporting systems (36.4%) than those without such experience (3.3%).

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Khamaj, Abdulrahman, e Ziho Kang. "Usability Evaluation of Mobile Weather Hazard Alert Applications". Industrial and Systems Engineering Review 6, n. 1 (1 ottobre 2018): 21–40. http://dx.doi.org/10.37266/iser.2018v6i1.pp21-40.

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Cell phones enable us to receive and respond to critical incidents, such as: severe storms, tornadoes, and flash floods. However, due to the small display size of cell phones, and regardless of simplified symbols or alert messages, it is possible to overlook users’ ability to interact with the available features and understand the messages in a timely manner. Untrained and trained users of the Weather Radio application participated in an experiment to perform three search tasks; (task 1: location search, task 2: alert settings, and task 3: map settings). In task 4, they evaluated two types of weather alert messages: original National Weather Service (NWS) messages vs. filtered (proposed) messages. By recording users’ completion time on the search tasks, the results showed that the time of the typing in text bar method for task 1 was significantly less than the pin on map method, while much more time was required to complete tasks 2 and 3 by the untrained users compared to the trained users. It was also revealed that the proposed messages were more effective than the original messages by both user groups. This research of user-centered designs provides a foundation to support the designs of time-critical mobile alert systems.

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Oyeyemi, Sunday O., e Rolf Wynn. "The use of cell phones and radio communication systems to reduce delays in getting help for pregnant women in low- and middle-income countries: a scoping review". Global Health Action 8, n. 1 (10 settembre 2015): 28887. http://dx.doi.org/10.3402/gha.v8.28887.

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Lonzetta, Angela, Peter Cope, Joseph Campbell, Bassam Mohd e Thaier Hayajneh. "Security Vulnerabilities in Bluetooth Technology as Used in IoT". Journal of Sensor and Actuator Networks 7, n. 3 (19 luglio 2018): 28. http://dx.doi.org/10.3390/jsan7030028.

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Bluetooth technology is a key component of wireless communications. It provides a low-energy and low-cost solution for short-range radio transmissions. Bluetooth, more specifically Bluetooth Low Energy (BLE) has become the predominant technology for connecting IoT (Internet of Things). It can be found in cell phones, headsets, speakers, printers, keyboards, automobiles, children’s toys, and medical devices, as well as many other devices. The technology can also be found in automated smart homes, to provide monitors and controls for lights, thermostats, door locks, appliances, security systems, and cameras. Bluetooth offers convenience and ease of use, but it lacks a centralized security infrastructure. As a result, it has serious security vulnerabilities, and the need for awareness of the security risks are increasing as the technology becomes more widespread. This paper presents an overview of Bluetooth technology in IoT including its security, vulnerabilities, threats, and risk mitigation solutions, as well as real-life examples of exploits. Our study highlights the importance of understanding attack risks and mitigation techniques involved with using Bluetooth technology on our devices. Real-life examples of recent Bluetooth exploits are presented. Several recommended security measures are discussed to secure Bluetooth communication.

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Nakai, Tomoo. "Magneto-Impedance Sensor Driven by 400 MHz Logarithmic Amplifier". Micromachines 10, n. 6 (29 maggio 2019): 355. http://dx.doi.org/10.3390/mi10060355.

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A thin-film magnetic field sensor is useful for detecting foreign matters and nanoparticles included in industrial and medical products. It can detect a small piece of tool steel chipping or breakage inside the products nondestructively. An inspection of all items in the manufacturing process is desirable for the smart manufacturing system. This report provides an impressive candidate for realizing this target. A thin-film magneto-impedance sensor has an extremely high sensitivity, especially, it is driven by alternatiing current (AC) around 500 MHz. For driving the sensor in such high frequency, a special circuit is needed for detecting an impedance variation of the sensor. In this paper, a logarithmic amplifier for detecting a signal level of 400 MHz output of the sensor is proposed. The logarithmic amplifier is almost 5 mm × 5 mm size small IC-chip which is widely used in wireless devices such as cell phones for detecting high-frequency signal level. The merit of the amplifier is that it can translate hundreds of MHz signal to a direct current (DC) voltage signal which is proportional to the radio frequency (RF)signal by only one IC-chip, so that the combination of a chip Voltage Controlled Oscillator (VCO), a magneto-impedance (MI) sensor and the logarithmic amplifier can compose a simple sensor driving circuit.

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Mallmann, E. J. J., A. S. B. Sombra, J. C. Goes e P. B. A. Fechine. "Yttrium Iron Garnet: Properties and Applications Review". Solid State Phenomena 202 (maggio 2013): 65–96. http://dx.doi.org/10.4028/www.scientific.net/ssp.202.65.

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Due to a fast progress in the development of communication systems, the dielectric and magnetic ceramics (ferrites) have become attractive to be used in devices. Although the ferrites of the spinel type were the first material to be used in the microwave range, garnets have smaller dielectric losses and, therefore, are chosen for many applications. High demands for modern electric applications in magnetic materials results in new techniques and products being permanently studied and researched, with a consequent appearance of new solutions for a wide applications series. This work presents the study of the ferrimagnetic composite, constituted by Y3Fe5O12 (YIG) and Gd3Fe5O12 (GdIG) phases, through solid state synthetic route and submitted to high-energy mechanical milling. Additionally, experiments were made in order to evaluate the electric and magnetic behavior of the composites at radio frequency and microwave range and then later suggest an adequate technological application. The composites were efficient as ferrite resonator antennas (FRAs) and microstrip antennas (thick films deposited on metalized surface alumina substrate by screen-printing technique), in the microwave frequency range. The experiments with FRAs showed satisfactory results due to the control of the antennas radiation characteristics and their tuning by the use of an external magnetic field. The composite resonators studied in this work can be important to the development of a third generation (3G) wideband antennas to cell phones and other wireless products.

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Dzarnoski, John, e Susie Johansson. "Embedding Active and Passive Devices in Medical Electronics". Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2014, DPC (1 gennaio 2014): 000786–814. http://dx.doi.org/10.4071/2014dpc-tp16.

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Efforts to increase the packaging efficiency of microelectronic systems have been extensive and continuous over the past few decades. Evidence of this can be seen even before the expansion of the space program by the United States in 1961 and the race to the moon; one of the first settings where size was truly limited and miniaturization of electronics was a necessity. In the 1950's the world saw its first major size reduction of electronic component with the phase out of the vacuum tube in favor of the transistor. The transistor saw its first major commercial use in 1952 via hybrid vacuum tube transistor technology. While many industries benefitted from the shift, in 1954 the hearing aid industry specifically experienced major improvements owing to the implementation of transistors, becoming smaller, requiring less power and having better functionality. The first 4-transistor AM radio product followed shortly thereafter. Much of today's effort since 1978 has been driven by the telecommunications industry that has succeeded in reducing cell phone size while simultaneously increasing functionality. Just as in the 1950's, hearing aid technology continues to be at the forefront when it comes to miniaturization. The hearing aid business has always had the need to use extremely small electronic packaging. The first completely in the canal (CIC) hearing aids were produced in 1993 and required all electronic components to be small enough that they fit entirely inside the ear canal. The introduction of wireless systems into hearing aids has sharply increased component count. Due to the size and shape of a multitude of types of hearing aids, flexible circuits need to be folded and bent to fit inside hearing aid cases, with essentially all available space being used. More powerful processors and more memory are enabling sophisticated algorithms that are able to greatly improve sound quality. There is also a strong market desire to add more features to hearing products while at the same time making them smaller and less visible. The latest hearing aids have succeeded in the later demand, constructed so small they are not visible and consequently are called invisible in the canal (IIC). In order to continue meeting the markets want for smaller and more features, a new packaging method needed to be developed. One such option is embedded die packaging. This paper will examine the use of embedded die packaging (or chip-in-flex) to drive significant further size reduction in custom and standard hearing instruments over what can be achieved using chip-on-flex or traditional ceramic hybrid based technologies. The historical drivers, available circuit board technologies, use of integrated passive devices, performance improvement, size reduction, device reliability, changes in supply chain, impact on wafer test, impact on device test, and challenges of working with wafers instead of die will be discussed.

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Seetharaman, Krishnan, Bart van Velzen, Hans van Zadelhoff, Cadmus Yuan, Frank Rietveld, Coen Tak, Joost van Beek et al. "A Robust Wafer-Level Capping Approach for MEMS Devices". Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2010, DPC (1 gennaio 2010): 000891–924. http://dx.doi.org/10.4071/2010dpc-tp21.

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Micro-electromechanical systems (MEMS) devices are extremely sensitive to their environment, especially at wafer-level, until they are packaged in final form. The harsh back-end (BE) operations that the MEMS devices have to endure include dicing, pick-and-place, wire bonding and molding. During these processing steps, the MEMS device is exposed to particles and contaminants. Therefore, protection at an early stage is a fundamental requirement. In this work, we describe a silicon nitride thin-film capping, which is processed using a sacrificial layer technique only with front-end technology. This approach is suitable for mass production of MEMS devices, owing to the fact that, it is more cost-effective when compared to other approaches such as wafer-to-wafer bonding and die-to-wafer bonding. A Bulk Acoustic Wave (BAW) resonator, that finds application in the Radio Frequency (RF) front end, e.g., in cell phones, is taken as a MEMS vehicle for our work. It is an example of an extremely sensitive MEMS device, because the resonance frequency shifts significantly when additional mass is accidentally deposited on its surface. The thickness of the silicon nitride capping that is required to withstand all the BE steps, in particular transfer molding, is estimated using simple analytical calculations and finite element model (FEM) simulations. The pressure acting on the thin film capping and the thermal load during molding are included in the FEM model. Using this, the minimum thickness required for the capping is determined. We prove that, a BAW resonator capped with silicon nitride at wafer-level can be wafer-thinned, diced, wire bonded and molded without major degradation in its performance.

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Seetharaman, Krishnan, Bart van Velzen, Johannes van Wingerden, Hans van Zadelhoff, Cadmus Yuan, Frank Rietveld, Coen Tak, Joost van Beek, Peter H. C. Magnée e Herman C. W. Beijerinck. "A Robust Thin-Film Wafer-Level Packaging Approach for MEMS Devices". Journal of Microelectronics and Electronic Packaging 7, n. 3 (1 luglio 2010): 175–80. http://dx.doi.org/10.4071/imaps.270.

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Abstract (sommario):

Micro-electromechanical systems (MEMS) devices are extremely sensitive to their environment, especially at the wafer level, until they are packaged in final form. The harsh back-end (BE) operations that the MEMS devices have to endure include dicing, pick-and-place, wire bonding, and molding. During these processing steps, the MEMS device is exposed to particles and contaminants. Therefore, protection at an early stage is a fundamental requirement. We describe a silicon nitride thin-film capping, which is processed using a sacrificial layer technique only with front-end technology. This approach is suitable for mass production of MEMS devices, owing to the fact that it is more cost-effective when compared to other approaches such as wafer-to-wafer bonding and die-to-wafer bonding. A bulk acoustic wave (BAW) resonator that finds application in the radio frequency (RF) front end, for example, in cell phones, is taken as a MEMS vehicle for our work. It is an example of an extremely sensitive MEMS device, because the resonance frequency shifts significantly when additional mass is accidentally deposited on its surface. The thickness of the silicon nitride capping that is required to withstand all the BE steps, in particular transfer molding, is estimated using simple analytical calculations and finite element model (FEM) simulations. The pressure acting on the thin film capping and the thermal load during molding are included in the FEM model. Using this, the minimum thickness required for the capping is determined. We prove that a BAW resonator capped with silicon nitride at the wafer level can be wafer-thinned, diced, wire bonded, and molded without major degradation in performance.

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Brennan, Thomas M., Joseph E. Jesson e Pedro Gilberto A. Furlanetto. "Quantifying driver cell phone use at signalized intersections using software-defined radio". Traffic Injury Prevention 20, n. 4 (30 aprile 2019): 359–64. http://dx.doi.org/10.1080/15389588.2019.1592167.

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Ogunbanjo, Gboyega A. "Cell phone use and ill health: Is there a definite relationship?" South African Family Practice 59, n. 3 (10 luglio 2017): 4. http://dx.doi.org/10.4102/safp.v59i5.4762.

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Abstract (sommario):

With the advent of the global use of cell phones, there have been concerns about their impact on the health of users. Interestingly, cell phone use is now an integral part of modern day communication between persons. In 2014, the World Health Organisation (WHO) estimated that there were 6.9 billion subscriptions globally and that in some parts of the world, mobile phones are the most reliable or the only phones available.1 Various studies have been conducted, although some are inconclusive on the link of cell phone use and ill health. Cell phones communicate by transmitting radio waves through a network of fixed antennas called base stations. Radio-frequency waves are electromagnetic fields, and unlike ionizing radiation such as X-rays or gamma rays, can neither break chemical bonds nor cause ionization in the human body.1

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Naji, Hamid Reza, Hossein Farahmand e Masoud RashidiNejad. "Capability Evaluation of Embedded Systems, Cell Phone Case Study". International Journal of Computer Applications 9, n. 10 (10 novembre 2010): 41–47. http://dx.doi.org/10.5120/1526-1696.

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Golden, Chloe, Charles J. Golden e Barry Schneider. "Cell Phone Use and Visual Attention". Perceptual and Motor Skills 97, n. 2 (ottobre 2003): 385–89. http://dx.doi.org/10.2466/pms.2003.97.2.385.

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GOLDEN, CHLOE. "CELL PHONE USE AND VISUAL ATTENTION". Perceptual and Motor Skills 97, n. 6 (2003): 385. http://dx.doi.org/10.2466/pms.97.6.385-389.

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Gill, Grandon. "EXPANDING JOINT VULNERABILITY ASSESSMENT BRANCH". Muma Case Review 1 (2016): 001–14. http://dx.doi.org/10.28945/3558.

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David Rohret, the founder of the Joint Vulnerability Assessment Branch (JVAB) pondered this difficult question. Since 2003, he had been involved in building a team that was uniquely positioned to identify a wide range of vulnerabilities in military and commercial communications and web-based systems. He could cite numerous examples of past situations where the early use of JVAB’s services led to, or could have led to, tens of millions of dollars in savings—or possibly more, had the issues they detected been left unattended. The value that JVAB offered was gradually being recognized and, as a result, demand for their services was building. The problem was that it was nearly impossible to hire people with the skills necessary to meet the growing need. There were a number of aspects of JVAB’s approach that made it unique. First and foremost, it had been early to recognize that formerly distinct elements of communications systems were rapidly converging. Historically, communications using radio frequency (RF) signals had been the domain of electrical engineers, while network communications were handled by computer scientists. As network traffic was increasingly being handled using cellular and wifi signals, however, RF intrusions became a serious threat. By the same token, RF communications—such as those handled using high end hand-held devices and cell phones—often relied on the same IP protocols used by the Internet—making them a potential pathway to servers. Another key aspect of JVAB was its adversarial mindset. It prided itself on using the same tools and techniques as the black hat hackers that threatened systems in real world settings. Not only was this an attitude that was generally not cultivated in educational institutions, it also ran counter to the experience of individuals that has spent all their professional life dealing with security in a defensive posture. In the past, Rohret had hired high potential individuals, usually with military experience, and had helped them develop their skills over many years. The end result was the formation of a team with an extraordinary track record of success. But if JVAB were to meet the continuing demand for its services, it needed to figure out new ways to expand. That could be a real challenge in an organization where the most valuable assets all wore shoes.

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Lin, James. "Are Radio Frequency or Cell Phone Fields Possibly Carcinogenic to Humans? [Health Effects]". IEEE Microwave Magazine 13, n. 4 (maggio 2012): 30–32. http://dx.doi.org/10.1109/mmm.2012.2189504.

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Jenab, Kouroush, e Ahmad Sarfaraz. "Selecting Cell Phone Service Using Hybrid Decision Making Methodology". International Journal of Enterprise Information Systems 9, n. 1 (gennaio 2013): 49–61. http://dx.doi.org/10.4018/jeis.2013010103.

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In an ever expanding connected world, mobile connectivity is essential in both commercial and private use. Selecting the best option has become increasingly difficult due to the many factors surrounding the selection of the best cell phone service providing company. Quantitative factors such as monthly price, total cell phone minutes, and phone cost are easily comparable. However, other qualitative factors such as signal coverage, vendor reputation, and customer support are not as easily analyzed. The need to make the correct decision when qualitative factors need to be considered has caused multi-criteria decision methodologies such as Analytical Hierarchy Process (AHP) to be applied in case studies. In this paper, the authors apply Fuzzy AHP to phone survey results and compare them to the original results. The multi-criteria decision methodology TOPSIS is used to demonstrate the differences between all decision methodologies.

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Ali, Marwah T., Yousif R. Muhsen, Raad Farhood Chisab e Sameeha N. Abed. "Evaluation Study of Radio Frequency Radiation Effects from Cell Phone Towers on Human Health". Radioelectronics and Communications Systems 64, n. 3 (marzo 2021): 155–64. http://dx.doi.org/10.3103/s0735272721030055.

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Nisar, Humaira, e Hamara Awadh. "Analysis of the Effect of Cell Phone Radiation on the Human Brain Using Electroencephalogram". Oriental journal of computer science and technology 9, n. 3 (3 ottobre 2016): 194–203. http://dx.doi.org/10.13005/ojcst/09.03.05.

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This paper aims to investigate the effect of cell phone radiation on human brain. It is known that the cell phone emits electromagnetic (EM) radiation which could be harmful to the human brain. In this research the electroencephalogram (EEG) signal has been acquired from 24 healthy subjects using a 16 channel EEG headset under different experimental conditions. The signal is decomposed into different brain rhythms using Daubechies Discrete Wavelet Transform up to 5th-level of the decomposition. Quantitative analysis has been carried out using two statistical parameters (Energy, Entropy) and Absolute Power. Special attention was focused on Temporal and Frontal lobes as these are near to the ear. Experimental results show higher values (for energy, entropy and absolute power) in the low-frequency bands (delta and theta) compared to the high frequency bands (alpha, beta and gamma) in both lobes. When the phone was placed 5cm away from the head there was less brain activation compared to when the cell phone was placed next to the ear/head on both sides. It was found that there was more effect on the right side compared to the left side from the cell phone’s radio waves.

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Kim, Ajung, Young Hoon Ju, Young Soo Kim e Sang Min Nahm. "Hybrid fiber radio systems for pico-cell communications". Microwave and Optical Technology Letters 33, n. 5 (24 aprile 2002): 328–30. http://dx.doi.org/10.1002/mop.10311.

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Moorleghen, Dylan M., Naresh Oli, Alison J. Crowe, Justine S. Liepkalns, Casey J. Self e Jennifer H. Doherty. "Impact of automated response systems on in‐class cell phone use". Biochemistry and Molecular Biology Education 47, n. 5 (30 maggio 2019): 538–46. http://dx.doi.org/10.1002/bmb.21257.

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Chang, Mau-Chung Frank. "Frank chang recognized for modern cell phone technology and WLAN systems". IEEE Solid-State Circuits Society Newsletter 11, n. 2 (maggio 2006): 1–3. http://dx.doi.org/10.1109/n-ssc.2006.6500129.

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Peng, B., R. Nan, T. Piao, D. Jiang, Y. Su, R. G. Strom, S. Wu, X. Zhang, L. Zhu e X. Liu. "Radio Interference in Astronomical Observatories of China". Symposium - International Astronomical Union 196 (2001): 307–10. http://dx.doi.org/10.1017/s0074180900164277.

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We first very briefly introduce the major radio facilities for astronomical research in China, and then report on the present interference situation at major radio observatories. Some of the radio interference problems are caused by paging services, mobile phone satellites, telemetry services for power supply, waterpower and earthquake activity, or radar systems, but some causes are unknown. In the worst case, harmful to radio astronomy, the Sesan VLBI station has not been able to do any observations at 92 cm due to serious radio interference problems since 1992. Still more serious interference coming from satellites can be expected in the next decade. International efforts on frequency protection should be urgently pursued if ground-based radio astronomy is to survive.

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Khan, Asra, Suad Naheed, Mehtab Alam e Saba Salahuddin. "Saliva - A New Horizon for Estimating Antioxidant Profile of Mobile Phone User". RADS Journal of Biological Research & Applied Sciences 10, n. 1 (16 luglio 2019): 23–29. http://dx.doi.org/10.37962/jbas.v10i1.154.

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This is the era of information and new technologies, among the brilliant inventions and advancement, Global system of mobile phone communication (GSM) makes the life as approachable as one can think. It changes the social relation and social network of an individual. Hence the mobile has two sides of a coin. Advantages and disadvantages are associated with every feasibility or inventions. But some time blessings bring some harmful effects on the human body. Mobile phone uses radio waves. Some part of the radio wave is also absorbed in the body. The ear is the most exposed part of the body. The salivary gland is very close to the ear. Hence, the affected part of the cellular phone radiations is a salivary gland. In the current study, we collected the unstimulated saliva sample from volunteers to estimate the antioxidant profile of the mobile phone user. The Uric acids, Catalase, C Reactive Protein (CRP), Reduced Glutathione (GSH), and Superoxide Dismutase (SOD) were included in the antioxidant profile. Uric acid, GSH, SOD was significantly decreased while CRP and Catalase were significantly increased. The result shows the increase the risk of inflammation and oxidative stress, which can predispose the cell phone user to a multitude of infectious & non-infectious oral diseases.

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Bagchi, Kallol, Peeter Kirs e Francisco López. "The impact of price decreases on telephone and cell phone diffusion". Information & Management 45, n. 3 (aprile 2008): 183–93. http://dx.doi.org/10.1016/j.im.2007.12.005.

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Yu, Chuan, Shuhui Chen e Zhiping Cai. "LTE Phone Number Catcher: A Practical Attack against Mobile Privacy". Security and Communication Networks 2019 (30 settembre 2019): 1–10. http://dx.doi.org/10.1155/2019/7425235.

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Phone number is a unique identity code of a mobile subscriber, which plays a more important role in the mobile social network life than another identification number IMSI. Unlike the IMSI, a mobile device never transmits its own phone number to the network side in the radio. However, the mobile network may send a user’s phone number to another mobile terminal when this user initiating a call or SMS service. Based on the above facts, with the help of an IMSI catcher and 2G man-in-the-middle attack, this paper implemented a practicable and effective phone number catcher prototype targeting at LTE mobile phones. We caught the LTE user’s phone number within a few seconds after the device camped on our rogue station. This paper intends to verify that mobile privacy is also quite vulnerable even in LTE networks as long as the legacy GSM still exists. Moreover, we demonstrated that anyone with basic programming skills and the knowledge of GSM/LTE specifications can easily build a phone number catcher using SDR tools and commercial off-the-shelf devices. Hence, we hope the operators worldwide can completely disable the GSM mobile networks in the areas covered by 3G and 4G networks as soon as possible to reduce the possibility of attacks on higher-generation cellular networks. Several potential countermeasures are also discussed to temporarily or permanently defend the attack.

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Al-Azzawi, Dr Med ShahabA Shakir, Dr AmerDawood Majed e Dr NadhimKhazal Noaman. "RADIO FREQUENCY ELECTROMAGNETIC RADIATION EXPOSURE EMITTEDFROM CELL PHONE ALTERS THE FSH, LH HORMONES LEVELIN VITRO." International Journal of Advanced Research 4, n. 12 (31 dicembre 2016): 2026–31. http://dx.doi.org/10.21474/ijar01/2618.

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Yang, Wei, Chundi Xiu, Jiarui Ye, Zhixing Lin, Haisong Wei, Dayu Yan e Dongkai Yang. "LSS-RM: Using Multi-Mounted Devices to Construct a Lightweight Site-Survey Radio Map for WiFi Positioning". Micromachines 9, n. 9 (12 settembre 2018): 458. http://dx.doi.org/10.3390/mi9090458.

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A WiFi-received signal strength index (RSSI) fingerprinting-based indoor positioning system (WiFi-RSSI IPS) is widely studied due to advantages of low cost and high accuracy, especially in a complex indoor environment where performance of the ranging method is limited. The key drawback that limits the large-scale deployment of WiFi-RSSI IPS is time-consuming offline site surveys. To solve this problem, we developed a method using multi-mounted devices to construct a lightweight site-survey radio map (LSS-RM) for WiFi positioning. A smartphone was mounted on the foot (Phone-F) and another on the waist (Phone-W) to scan WiFi-RSSI and simultaneously sample microelectromechanical system inertial measurement-unit (MEMS-IMU) readings, including triaxial accelerometer, gyroscope, and magnetometer measurements. The offline site-survey phase in LSS-RM is a client–server model of a data collection and preprocessing process, and a post calibration process. Reference-point (RP) coordinates were estimated using the pedestrian dead-reckoning algorithm. The heading was calculated with a corner detected by Phone-W and the preassigned site-survey trajectory. Step number and stride length were estimated using Phone-F based on the stance-phase detection algorithm. Finally, the WiFi-RSSI radio map was constructed with the RP coordinates and timestamps of each stance phase. Experimental results show that our LSS-RM method can reduce the time consumption of constructing a WiFi-RSSI radio map from 54 min to 7.6 min compared with the manual site-survey method. The average positioning error was below 2.5 m with three rounds along the preassigned site-survey trajectory. LSS-RM aims to reduce offline site-survey time consumption, which would cut down on manpower. It can be used in the large-scale implementation of WiFi-RSSI IPS, such as shopping malls, hospitals, and parking lots.

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Qin, Tianyun, Rangding Wang, Diqun Yan e Lang Lin. "Source Cell-Phone Identification in the Presence of Additive Noise from CQT Domain". Information 9, n. 8 (17 agosto 2018): 205. http://dx.doi.org/10.3390/info9080205.

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With the widespread availability of cell-phone recording devices, source cell-phone identification has become a hot topic in multimedia forensics. At present, the research on the source cell-phone identification in clean conditions has achieved good results, but that in noisy environments is not ideal. This paper proposes a novel source cell-phone identification system suitable for both clean and noisy environments using spectral distribution features of constant Q transform (CQT) domain and multi-scene training method. Based on the analysis, it is found that the identification difficulty lies in different models of cell-phones of the same brand, and their tiny differences are mainly in the middle and low frequency bands. Therefore, this paper extracts spectral distribution features from the CQT domain, which has a higher frequency resolution in the mid-low frequency. To evaluate the effectiveness of the proposed feature, four classification techniques of Support Vector Machine (SVM), Random Forest (RF), Convolutional Neural Network (CNN) and Recurrent Neuron Network-Long Short-Term Memory Neural Network (RNN-BLSTM) are used to identify the source recording device. Experimental results show that the features proposed in this paper have superior performance. Compared with Mel frequency cepstral coefficient (MFCC) and linear frequency cepstral coefficient (LFCC), it enhances the accuracy of cell-phones within the same brand, whether the speech to be tested comprises clean speech files or noisy speech files. In addition, the CNN classification effect is outstanding. In terms of models, the model is established by the multi-scene training method, which improves the distinguishing ability of the model in the noisy environment than single-scenario training method. The average accuracy rate in CNN for clean speech files on the CKC speech database (CKC-SD) and TIMIT Recaptured Database (TIMIT-RD) databases increased from 95.47% and 97.89% to 97.08% and 99.29%, respectively. For noisy speech files with seen noisy types and unseen noisy types, the performance was greatly improved, and most of the recognition rates exceeded 90%. Therefore, the source identification system in this paper is robust to noise.

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Rice, Ronald E., e James E. Katz. "Assessing new cell phone text and video services". Telecommunications Policy 32, n. 7 (agosto 2008): 455–67. http://dx.doi.org/10.1016/j.telpol.2008.05.005.

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Bagherinia, Homayoun, e Roberto Manduchi. "Robust real-time detection of multi-color markers on a cell phone". Journal of Real-Time Image Processing 8, n. 2 (3 giugno 2011): 207–23. http://dx.doi.org/10.1007/s11554-011-0206-9.

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43

Tsarna, Ermioni, Marije Reedijk, Laura Ellen Birks, Mònica Guxens, Ferran Ballester, Mina Ha, Ana Jiménez-Zabala et al. "Associations of Maternal Cell-Phone Use During Pregnancy With Pregnancy Duration and Fetal Growth in 4 Birth Cohorts". American Journal of Epidemiology 188, n. 7 (17 aprile 2019): 1270–80. http://dx.doi.org/10.1093/aje/kwz092.

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Abstract Results from studies evaluating potential effects of prenatal exposure to radio-frequency electromagnetic fields from cell phones on birth outcomes have been inconsistent. Using data on 55,507 pregnant women and their children from Denmark (1996–2002), the Netherlands (2003–2004), Spain (2003–2008), and South Korea (2006–2011), we explored whether maternal cell-phone use was associated with pregnancy duration and fetal growth. On the basis of self-reported number of cell-phone calls per day, exposure was grouped as none, low (referent), intermediate, or high. We examined pregnancy duration (gestational age at birth, preterm/postterm birth), fetal growth (birth weight ratio, small/large size for gestational age), and birth weight variables (birth weight, low/high birth weight) and meta-analyzed cohort-specific estimates. The intermediate exposure group had a higher risk of giving birth at a lower gestational age (hazard ratio = 1.04, 95% confidence interval: 1.01, 1.07), and exposure-response relationships were found for shorter pregnancy duration (P < 0.001) and preterm birth (P = 0.003). We observed no association with fetal growth or birth weight. Maternal cell-phone use during pregnancy may be associated with shorter pregnancy duration and increased risk of preterm birth, but these results should be interpreted with caution, since they may reflect stress during pregnancy or other residual confounding rather than a direct effect of cell-phone exposure.

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Sutton, Todd. "Power Management in Modern Cell Phones". Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2019, DPC (1 gennaio 2019): 000729–48. http://dx.doi.org/10.4071/2380-4491-2019-dpc-gbc3_qualcomm.

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The second largest thing in your cell phone is the battery and roughly half of the electronics is associated with power management. This talk will provide an overview of these systems and shed some light on the challenges in the not so distant away future.

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Kanan, Riad, e Obaidallah Elhassan. "A Combined Batteryless Radio and WiFi Indoor Positioning for Hospital Nursing". Journal of Communications Software and Systems 12, n. 1 (22 marzo 2016): 34. http://dx.doi.org/10.24138/jcomss.v12i1.89.

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This paper proposes a design of an efficient hospital nurse calling system which combines two types of indoor localization systems. The purpose of the first system is to locate patients while the second is to locate nurses equipped with their smart phones. The main goal of developing such system is to decrease the time taking for nurses to provide healthcare for patients. Patients' positioning system is RF based. Indeed, each patient is equipped with a wireless and battery-free call button. When the switch is pressed, a wireless telegram is sent to reference nodes that act like Wireless Sensor Networks (WSN). The positioning of patient is performed using trilateration method with the help of Received Signal Strength Indicator (RSSI) values. Hence, beacons will forward the received signal from patient’s call button to a central receiver module connected to a computer. A dedicated program has been developed to calculate the position of the call button and post it on an online database. On the other hand, the nurses’ localization system is WiFi-based. Nurses' positioning is done by determining the Time of Arrival (ToA) and the Angle of Arrival (AoA) between the mobile phone and the WiFi router. The mobile phone locations are posted to the online database as well. Our program performs a comparison between the nurses' and the patient's coordinates. The nearest nurse gets an alarm. As consequence, a patient gets care from the nearest available nurse in an efficient way and with less time. The proposed system is user-friendly and Internet of Things (IoT) based architecture integrating two heterogeneous localization systems seamlessly.

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Kawada, T., K. Nakamichi, N. Hisano, M. Kitamura e K. Miyahara. "Cell-phone based assistance for waterworks/sewage plant maintenance". Water Science and Technology 53, n. 4-5 (1 febbraio 2006): 245–52. http://dx.doi.org/10.2166/wst.2006.129.

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Cell-phones are now incorporating the functions necessary for them to be used as mobile IT devices. In this paper, we present our results of the evaluation of cell-phones as the mobile IT device to assist workers in industrial plants. We use waterworks and sewage plants as examples. By employing techniques to squeeze the SCADA screen on CRT into a small cell-phone LCD, we have made it easier for a plant's field workers to access the information needed for effective maintenance, regardless of location. An idea to link SCADA information and the plant facility information on the cell-phone is also presented. Should an accident or emergency situation arise, these cell-phone-based IT systems can efficiently deliver the latest plant information, thus the worker out in the field can respond to and resolve the emergency.

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Simpson, Stephen. "Theatre of Sound: Radio and the Drama of the Imagination. By Dermot Rattigan. Dublin: Carysfort Press, 2003; pp. 384. $27.95 paper." Theatre Survey 45, n. 1 (maggio 2004): 139–40. http://dx.doi.org/10.1017/s0040557404320089.

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Anyone old enough to remember the wailing sirens and portentous footsteps of Gangbusters or the clattering consequences of opening the closet door belonging to Fibber McGee and Molly probably has a soft spot for the radio dramas of the past. Those who never experienced the medium that George Bernard Shaw called “the invisible play” may lack a context. Admitting that you remember those nostalgic broadcasts dates you. In a world of HDTV, GPS, home THX, and digital imaging by cell phone, what good is radio?

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Amin, Md Nurul, Md Sultan Ul Islam e Md Jawadul Haque. "Impact of Cell-phone on Human Health: A Systematic Review of Literatures". Ibrahim Cardiac Medical Journal 8, n. 1-2 (6 luglio 2019): 53–65. http://dx.doi.org/10.3329/icmj.v8i1-2.53976.

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The growth of communication technology in the last two decades has given the world a new look.With the blessings of digital technology, we can now communicate to any parts of the world with just a touch over the screen of our smart phone. Mobile phone hasnow become an indispensable part of our life.But, biological effects of radio-frequency electromagnetic fields (EMF) transmitted by mobile phones are still a matter of public and scientific debate. Countries accross the world are now getting concerned about the impact of mobiles on human health and environment.Radiofrequency waves generated from mobile phones cause potential public health problems. Short-term effects like changes in sleep, heart rate, and blood pressure, and long-term effects like carcinoma (particularly glioma) are well-documented. International Agency for Research on Cancer (IARC) published cancer risks from Radiofrequency(RF) radiation. Human epidemiological studies gave evidence of increased risk for glioma and acoustic neuroma. Further epidemiological, animal and mechanistic studies have strengthened the association. Besides, the carcinogenic effect of non-ionizing radiation emitted from cordless digital devices, numerous health effects have already been claimed to occur. Faced with this context, scientific community and legislative bodies are raising voice for the reduction of RF-EMF exposure to the safe limit for human health and environment. The RF exposure restriction guideline used by many agencies was established in 1998 by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and was based only on established short-term thermal (heating) effects from RF radiation neglecting non-thermal biological effects. The present study is, therefore, intended to review the literatures relating mobile phone and Wi-fito human health in order to make the scientific community updated on the association between mobile phone use and human health. Ibrahim Card Med J 2018; 8 (1&2): 53-65

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Cama-Pinto, Dora, Miguel Damas, Juan Antonio Holgado-Terriza, Francisco Gómez-Mula, Andrés Camilo Calderin-Curtidor, Juan Martínez-Lao e Alejandro Cama-Pinto. "5G Mobile Phone Network Introduction in Colombia". Electronics 10, n. 8 (13 aprile 2021): 922. http://dx.doi.org/10.3390/electronics10080922.

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The deployment of the 5G mobile network is currently booming, offering commercially available services that improve network performance metrics by minimizing network latency in countries such as the USA, China, and Korea. However, many countries around the world are still in the pilot phase promoted and regulated by government agencies. This is the case in Colombia, where the assignment of the first 5G band is planned for the third quarter of 2021. By analyzing the results of the pilot phase and the roadmap of the Colombian Ministry of Information and Communication Technologies (MinTIC), we can determine the main issues, which contribute to the deployment of 5G mobile technology as well as the plans to achieve a 5G stand-alone network from 4G networks. This is applicable to other countries in Latin America and the world. Then, our objective is to synthesize and share the most important concepts of 5G mobile technology such as the MIMO (multiple input/multiple output) antenna, RAN (Radio Access Network), C-RAN (Centralised-RAN), and frequency bands, and evaluate the current stage of its introduction in Colombia.

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Lee, David, Joshua Lee e Imshik Lee. "Cell phone-generated radio frequency electromagnetic field effects on the locomotor behaviors of the fishesPoecilia reticulataandDanio rerio". International Journal of Radiation Biology 91, n. 10 (8 luglio 2015): 843–50. http://dx.doi.org/10.3109/09553002.2015.1062575.

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