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Towards Security of GSM Voice Communication
Global system for mobile communication (GSM) is widely used digital mobile service around the world. Although GSM was designed as a secure wireless system, it is now vulnerable to different targeted attacks. There is a need to address security domains especially the confidentiality of communication. This paper presents a novel framework for end to end secure voice communication over the GSM networks using encryption algorithm AES-256. A special Modem and speech coding technique are designed to enable the transmission of encrypted speech using GSM voice channel. To the best of our knowledge, this is first solution that uses single codebook for transmission of secure voice. An efficient low bit-rate (1.9Â kbps) speech coder is also designed for use with the proposed modulation scheme for optimal results. Different speech characteristics such as pitch, energy and line spectral frequencies are extracted and preserved before compression and encryption of speech. Previously, the best achieved data rate was 1.6Â kbps with three codebooks, whilst the proposed approach achieves 2Â kbps with 0% bit error rate. The empirical results show that the methodology can be used for real time applications to transmit encrypted voice using GSM network
Solar Energy Conversion and Noise Characterization in Photovoltaic Devices with Ventilation
An investigation is performed on solar energy conversion and noise characterization in photovoltaic devices with ventilation. A parallel plate photovoltaic (PV) device was installed with a pair of PV modules, a ventilated air cavity, and an insulating back panel of plywood board filled with polystyrene installed in an outdoor test room. The characterization of noise interference due to power difference of two intensities for composite waves on a PV device is presented. Standard definitions of noise sources, their measurement equations, their units, and their origins under limiting reference conditions are devised. The experiments were conducted for obtaining currents, voltages, temperatures, air velocities, sensible heat capacity, and thermal storage capacity of a PV device with active ventilation through an outdoor test room. Photovoltaic amplification was attained with power output from a potentiometer through the rotation of its circular knob. A parallel plate PV device was studied for its electrical parameters as resistance-capacitance (RC) electrical analog circuit. The effect of inductive and capacitive heating losses was considered in evaluating electrical characteristics of a PV device exposed to solar radiation. Noise filter systems as per noise sources are illustrated with examples. Some examples of noise unit calculations are tabulated based on devised noise measurement equations
Wireless Generation for 2020 - 5G Technology and Introduction to Its Vital Technology Components
When the advanced technology is introduced it gives more user friendly environment to customers. This is what 5G gives us than earlier wireless generations. 5G provides us enhanced capabilities of LTE-Advanced (LTE-A) i.e. 4G generation. Today 4G is still being under improvement, but early designs have started on its replacement: 5G. The 5G means the fifth generation of wireless or mobile communication. 5G is an end-to-end system which enables a fully mobile and connected society. 5G is capable of gives very high achievable data rates, very little latency and high consistency. It also supports the handling tremendous device densities. The main technology components gives extension to higher frequency bands, advanced multi-antenna transmission, tilt design, user/organize separation, stretchy spectrum usage, balancing device-to-device communication. 5G will supports 1000 times higher mobile data volume per area, 10 times to 100 times higher number of connected devices, 10 times to 100 times higher typical user data rate, 10 times longer battery life for low power Massive Machine Communication (MMC) devices, 5 times reduced End-to-End (E2E) latency[1]. The fifth generation of mobile technology (5G) is located to address the demands and business contexts of 2020 and beyond. It is anticipated to enable a fully mobile and connected society and to permit socio-economic transmissions in number of ways for good organization, sustainability and comfort. The burdens of a fully mobile and connected society are characterized by the fantastic growth in connectivity and amount of traffic.
DOI: 10.17762/ijritcc2321-8169.150511
Community rotorcraft air transportation benefits and opportunities
Information about rotorcraft that will assist community planners in assessing and planning for the use of rotorcraft transportation in their communities is provided. Information useful to helicopter researchers, manufacturers, and operators concerning helicopter opportunities and benefits is also given. Three primary topics are discussed: the current status and future projections of rotorcraft technology, and the comparison of that technology with other transportation vehicles; the community benefits of promising rotorcraft transportation opportunities; and the integration and interfacing considerations between rotorcraft and other transportation vehicles. Helicopter applications in a number of business and public service fields are examined in various geographical settings
A research to reduce interior noise in general aviation airplanes. General aviation interior noise study
The construction, calibration, and properties of a facility for measuring sound transmission through aircraft type panels are described along with the theoretical and empirical methods used. Topics discussed include typical noise source, sound transmission path, and acoustic cabin properties and their effect on interior noise. Experimental results show an average sound transmission loss in the mass controlled frequency region comparable to theoretical predictions. The results also verify that transmission losses in the stiffness controlled region directly depend on the fundamental frequency of the panel. Experimental and theoretical results indicate that increases in this frequency, and consequently in transmission loss, can be achieved by applying pressure differentials across the specimen
Internet of robotic things : converging sensing/actuating, hypoconnectivity, artificial intelligence and IoT Platforms
The Internet of Things (IoT) concept is evolving rapidly and influencing newdevelopments in various application domains, such as the Internet of MobileThings (IoMT), Autonomous Internet of Things (A-IoT), Autonomous Systemof Things (ASoT), Internet of Autonomous Things (IoAT), Internetof Things Clouds (IoT-C) and the Internet of Robotic Things (IoRT) etc.that are progressing/advancing by using IoT technology. The IoT influencerepresents new development and deployment challenges in different areassuch as seamless platform integration, context based cognitive network integration,new mobile sensor/actuator network paradigms, things identification(addressing, naming in IoT) and dynamic things discoverability and manyothers. The IoRT represents new convergence challenges and their need to be addressed, in one side the programmability and the communication ofmultiple heterogeneous mobile/autonomous/robotic things for cooperating,their coordination, configuration, exchange of information, security, safetyand protection. Developments in IoT heterogeneous parallel processing/communication and dynamic systems based on parallelism and concurrencyrequire new ideas for integrating the intelligent “devices”, collaborativerobots (COBOTS), into IoT applications. Dynamic maintainability, selfhealing,self-repair of resources, changing resource state, (re-) configurationand context based IoT systems for service implementation and integrationwith IoT network service composition are of paramount importance whennew “cognitive devices” are becoming active participants in IoT applications.This chapter aims to be an overview of the IoRT concept, technologies,architectures and applications and to provide a comprehensive coverage offuture challenges, developments and applications
Analysis of Impact of Natural Ventilation Strategies in Ventilation Rates and Indoor Environmental Acoustics Using Sensor Measurement Data in Educational Buildings
Indoor environmental conditions can significantly affect occupants’ health and comfort.
These conditions are especially important in educational buildings, where students, teachers and
staff spend long periods of the day and are vulnerable to these factors. Recently, indoor air quality
has been a focus of attention to ensure that disease transmission in these spaces is minimised. In
order to increase the knowledge in this field, experimental tests have been carried out to characterise
the impact of natural ventilation strategies on indoor air quality and the acoustic environment.
This study has evaluated three ventilation scenarios in four different classrooms in buildings of the
University of Granada, considering different window and door opening configurations. Ventilation
rates were estimated using the CO2 Decay Method, and background noise recordings were made
in each classroom for acoustic tests. Results show that specific natural ventilation strategies have a
relevant impact that is worth considering on the background noise in indoor spaces. In this sense
ventilation rates provided by the different configurations varied between 3.7 and 39.8 air changes
per hour (ACH) and the acoustic tests show a background noise ranging from 43 to 54 dBA in these
scenarios. Consequently, managers and teachers should take into account not only the ACH, but also
other collateral impacts on the indoor environmental conditions such as the thermal comfort or the
acoustic environment.Consejo General de la Arquitectura TĂ©cnica (CGATE)State Research Agency (SRA) of Spain and European Regional Development Funds (ERDF)
under project PID2019-108761RB-I00
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