3,222 research outputs found

    The Goddard program of gamma ray transient astronomy

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    Gamma ray burst studies are reviewed. The past results, present status and future expectations are outlined regarding endeavors using experiments on balloons, IMP-6 and -7, OGO-3, ISEE-1 and -3, Helios-2, Solar Maximum Mission, the Einstein Observatory, Solar Polar and the Gamma Ray Observatory, and with the interplanetary gamma ray burst networks, to which some of these spacecraft sensors contribute. Additional emphasis is given to the recent discovery of a new type of gamma ray transient, detected on 1979 March 5

    Novel Sampling Algorithm for Human Mobility-Based Mobile Phone Sensing

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    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

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    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

    Human-mobility-based sensor context-aware routing protocol for delay-tolerant data gathering in multi-sink cell-phone-based sensor networks

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    Ubiquitous use of cell phones encourages development of novel applications with sensors embedded in cell phones. The collection of information generated by these devices is a challenging task considering volatile topologies and energy-based scarce resources. Further, the data delivery to the sink is delay tolerant. Mobility of cell phones is opportunistically exploited for forwarding sensor generated data towards the sink. Human mobility model shows truncated power law distribution of flight length, pause time, and intercontact time. The power law behavior of inter-contact time often discourages routing of data using naive forwarding schemes. This work exploits the flight length and the pause time distributions of human mobility to design a better and efficient routing strategy. We propose a Human-Mobility-based Sensor Context-Aware Routing protocol (HMSCAR), which exploits human mobility patterns to smartly forward data towards the sink basically comprised of wi-fi hot spots or cellular base stations. The simulation results show that HMSCAR significantly outperforms the SCAR, SFR, and GRAD-MOB on the aspects of delivery ratio and time delay. A multi-sink scenario and single-copy replication scheme is assumed

    IIT Hyderabad-incubated PURE EV raises VC funding from pharma visionary

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    Indian Institute of Technology Hyderabad-incubated startup PURE EV has raised Venture Capital funding from Hyderabad-based pharmaceuticals visionary Shri V.C. Nannapaneni, in his personal capacity

    An efficient adaptive fusion scheme for multifocus images in wavelet domain using statistical properties of neighborhood

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    In this paper we present a novel fusion rule which can efficiently fuse multifocus images in wavelet domain by taking weighted average of pixels. The weights are adaptively decided using the statistical properties of the neighborhood. The main idea is that the eigen value of unbiased estimate of the covariance matrix of an image block depends on the strength of edges in the block and thus makes a good choice for weight to be given to the pixel, giving more weightage to pixel with sharper neighborhood. The performance of the proposed method have been extensively tested on several pairs of multifocus images and also compared quantitatively with various existing methods with the help of well known parameters including Petrovic and Xydeas image fusion metric. Experimental results show that performance evaluation based on entropy, gradient, contrast or deviation, the criteria widely used for fusion analysis, may not be enough. This work demonstrates that in some cases, these evaluation criteria are not consistent with the ground truth. It also demonstrates that Petrovic and Xydeas image fusion metric is a more appropriate criterion, as it is in correlation with ground truth as well as visual quality in all the tested fused images. The proposed novel fusion rule significantly improves contrast information while preserving edge information. The major achievement of the work is that it significantly increases the quality of the fused image, both visually and in terms of quantitative parameters, especially sharpness with minimum fusion artifacts

    IIT Hyderabad’s CfHE to Graduate Third Batch of Entrepreneurs and Startups

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    ndian Institute of Technology Hyderabad’s Center for Healthcare Entrepreneurship (CfHE) will mark the graduation of its third batch on Thursday (8th August 2019) by hosting a ‘pitching session’ for its Fellows with Investors, Venture Capital and Private Equity firms. This pitching session will help the CfHE Fellows convert their ideas and innovations into health technology products that will cater to some of the unmet needs of Indian Healthcare Sector

    IIT Hyderabad-Incubated Startup PURE EV Raises VC funding at USD 35 Million Valuation

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    Indian Institute of Technology Hyderabad-incubated startup PURE EV has raised Venture Capital funding from Hyderabad-based pharmaceuticals visionary Shri V.C. Nannapaneni, in his personal capacity

    Pitch session at IIT-H for CfHE Fellows on August 8

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    The third batch of fellows at Indian Institute of Technology Hyderabad Center for Healthcare Entrepreneurship (CfHE) will pitch their ideas to investors, venture capital firms and private equity players on August 8
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