628 research outputs found
IoT enabled communication device with mixer less low complex QPSK based transmitter architecture for low frequency applications
echnological development in the area of wireless communications lead to the requirement of tight integration of both the digital and analog functional units. Integrating mixers is a challenging task, especially in mixed signal design. IoT communication devices require low design complexity as we expect millions of devices connected. In this paper we propose a mixer less low complex QPSK based transmitter architecture targeting low frequency applications which reduced the complexity in transmitter design. A prototype has been developed using Bipolar Junction Transistors (BJTs) and FPGA as the base band controller. The design can easily be adapted to MOSFET technology and modulation is achieved without the need of generating the carrier externally. The prototype developed was tested successfully by generating frequencies of range varying from 1 KHz to 120 MHz. The proposed architecture can also be used for any other digital modulation scheme such as BPSK, FSK etc
Novel Sampling Algorithm for Human Mobility-Based Mobile Phone Sensing
Smart phones or mobile phones enabled with global positioning system (GPS), different types of sensors, and communication technologies have become ubiquitous application development platform for Internet of Things (IoT) and new sensing technologies. Improving sensing area coverage, reducing overlap of sensing area, and energy consumption are important issues under mobile phone sensing. This paper presents human mobility-based mobile phone sensors sampling algorithm. Human mobility patterns and geographical constraints have an impact on performance of mobile phone sensing applications. The real-outdoor location traces of volunteers, collected using GPS-enabled mobile phones are used for performance analysis of proposed work. The proposed mobile phone sensor sampling algorithm considers velocity of human mobility as an important parameter for improving sensing area coverage and reduction of energy consumption. To an extent overlap between sensing area coverage is allowed to overcome, the reduction of sensor data samples caused by spatial regularities of human mobility. The performance is analyzed and evaluated by considering general regular sampling and proposed sampling method for mobile phone sensing activity. The results show that for normal human walking velocity (<;1.5 m/s) proposed mobile phone sensor sampling algorithm performs better in terms of sensing area coverage and reduction of battery energy consumption for mobile phone sensing activity
Levy walk based multi-hop data forwarding protocol for opportunistic mobile phone sensor networks
Unstable link connectivity due to dynamic mobility nature of mobile phone users and error prone wireless link quality increases end-to-end delay for mobile phone based opportunistic network applications. This problem becomes more worse in the presence of large amount of data transmission, like multimedia data. This paper refers to Levy walk based multi-hop data forwarding protocol called Data Transmission Time and Human Walk Velocity (DTT-HWV) for Opportunistic Mobile Phone Sensor Networks (OMPSN). This paper, in particular evaluates the performance of proposed protocol in terms of end-to-end waiting time to receive data, which is an important QoS requirement for data transmission in opportunistic networks. The proposed protocol DTT-HWV reduces end-to-end waiting time to receive data compared to Random Progress (RP) data forwarding method in presence of low battery power and high path loss. Obtained results are helpful in designing and building of large scale data retrieval services for opportunistic networks involving humans in the communication network loop
Real Time Net Zero Energy Building Energy Manager with Heterogeneous Wireless Ad hoc Network Adaptable To IoT Architectures
Significant energy consumption by buildings from utility grid has made researchers revisit existing Building Energy Management Systems (BEMS). Most of the developing countries have taken a green initiative of Net Zero Energy Buildings (NZEB) to reduce carbon foot print and fast depletion of conventional energy sources. Though the integration of solar and wind based systems to grid is successful in recent years, residential building energy management systems with renewable energy sources is still an evolving research area. Monitoring, control and actuation systems should be tightly coupled with the help of any to any device communication namely Internet of Things (IoT) to realize an efficient NZEB. In this paper a real time NZEB is proposed and developed with bi-directional wireless sensor and actuation system. Proposed NZEB central server collects and maintains a database of on site solar generation, battery state of charge and load power consumption data of a building with help of IEEE 802.15.4 and IEEE 802.11 wireless networks. Proposed system was deployed as a test bed with sensing, control, actuation and server modules and connecting them with a bi-directional wireless network architecture similar to IoT. Data observed at experimental test bed confirm that developed system can estimate on site solar power generation, state of charge on battery bank and load power consumption with negligible error. A simulation study with experimental data collected at NZEB test bed shows that NZEB can optimally schedule loads between local generation and utility grid thereby minimizing peak demand on the grid
A low power IoT network for smart agriculture
Traditional agriculture is transforming into smart
agriculture due to the prominence of the Internet of Things (IoT).
Low-cost and low-power are the key factors to make any IoT
network useful and acceptable to the farmers. In this paper,
we have proposed a low-power, low-cost IoT network for smart
agriculture. For monitoring the soil moisture content, we have
used an in-house developed sensor. In the proposed network, the
IITH mote is used as a sink and sensor node which provides
low-power communication. We have evaluated our network with
state of the art networks, proposed for agriculture monitoring.
Power and cost are the two metrics used for evaluation of these
networks. Results show that the proposed network consumes less
power and has prolonged lifetime in the agriculture field
Real Time Wireless Air Pollution Monitoring system
Air pollution has
significant influence on the concentration of
constituents in the atmosphere leading to effects like global warming
and acid rains. To avoid such adverse imbalances in the nature, an
air pollution monitoring system is utmost important. This paper
attempts
to develop an effective solution for pollution monitoring
using wireless sensor networks (WSN) on a real time basis namely
real time wireless air pollution monitoring system. Commercially
available discrete gas sensors for sensing concentration of gases l
ike
CO
2
, NO
2,
CO and O
2
are calibrated using appropriate calibration
technologies. These pre
-
calibrated gas sensors are then integrated
with the wireless sensor motes for field deployment at the campus and
the Hyderabad city using multi hop data aggregatio
n algorithm. A
light weight middleware and a web interface to view the live pollution
data in the form of numbers and charts from the test beds was
developed and made available from anywhere on the internet. Other
parameters like temperature and humidity w
ere also sensed along
with gas concentrations to enable data analysis through data fusion
techniques. Experimentation carried out using the developed wireless
air pollution monitoring system under different physical conditions
show that the system collects
reliable source of real time fine
-
grain
pollution data
FPGA-Based Portable Ultrasound Scanning System with Automatic Kidney Detection
Bedsides diagnosis using portable ultrasound scanning (PUS) offering comfortable diagnosis with various clinical advantages, in general, ultrasound scanners suffer from a poor signal-to-noise ratio, and physicians who operate the device at point-of-care may not be adequately trained to perform high level diagnosis. Such scenarios can be eradicated by incorporating ambient intelligence in PUS. In this paper, we propose an architecture for a PUS system, whose abilities include automated kidney detection in real time. Automated kidney detection is performed by training the Viola–Jones algorithm with a good set of kidney data consisting of diversified shapes and sizes. It is observed that the kidney detection algorithm delivers very good performance in terms of detection accuracy. The proposed PUS with kidney detection algorithm is implemented on a single Xilinx Kintex-7 FPGA, integrated with a Raspberry Pi ARM processor running at 900 MHz
Seroprevalence of hepatitis B virus among patients at a rural tertiary health care centre in South India: a four year study
Background: Infection with the Hepatitis B Virus (HBV) is a global health problem. Epidemiological studies worldwide show wide variations in the prevalence patterns of the Hepatitis B infections. Early detection can contribute substantially to the timely diagnosis of the patients with acute illnesses and to an early treatment and hence, it can limit the transmission of the infection.Aim: To provide a baseline data on the prevalence of Hepatitis B among the patients who were attending Chennai Medical College Hospital and Research Centre, Trichy, Tamilnadu, over a period of 4 years (2010-2013).Methods: This was a retrospective study which was carried out among 19,513 patients who were attending the rural tertiary care teaching hospital, Trichy, over a period of 4 years (January 2010 – December 2013). The sera were screened for the presence of Hepatitis B surface antigen (HBsAg) by HEPACARD. Those found positive on screening test were confirmed by Enzyme linked Immuno-sorbent Assay (ELISA) test.Results: Out of 19,513 sera which were studied, 315 (1.61%) were sero-positive cases. Among the positive cases (315), the seroprevalence in males and females were 73% (230) and 27% (85) respectively and the frequency of HBV among age groups 0-20, 21-40, 41-60, >60 was 5.07% (16), 45.07% (142), 35.9% (113),11425% (36) respectively. Among the positive cases, a majority were in the age group of 21 to 40 years, with a male preponderance (p<0.05). Conclusion: The overall prevalence for this HBsAg marker among the patients who attended the rural tertiary teaching hospital in this study was comparatively similar to that which was reported by other studies from India.
Gravitational Waves From Known Pulsars: Results From The Initial Detector Era
We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom
FASTRA – SAFE AND SECURE
The innovative congestion control algorithm named FASTRA (Fast Active Stability TCP) is aimed for high-speed long-latency networks. Four major difficulties in FASTRA are highlighted at both packet and flow levels. The architecture and characterization of equilibrium and stability properties of FASTRA are robust. Experimental results of FASTRA outsmart TCP Reno, HSTCP, and STCP in terms of throughput, fairness, stability, and responsiveness. FASTRA aims to rapidly stabilize high-speed long-latency networks into steady, efficient and fair operating points, in dynamic sharing environments, and the preliminary results are produced as output of our project. The Proposed architecture is explained with the help of an existing real-time example as to explain why FASTRA download is chosen rather than FTP download. The Paper is concluded with the results of the new congestion control algorithm aided with the graphs obtained during its simulation in NS2. On proper implementation, many safe, FASTRA downloads and data transfers can be carried over a high speed internet network
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