Browsing by Author "Saurabh, Kumar"

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    360 Degree Solar Tracking And Automatic Cleaning System
    (2015-12-22T09:16:43Z) Suman, Choudhary; Sneha, Kumar; Saurabh, Kumar; Neeraj, Kumar
    The solar PV modules are generally employed in dusty environments which is the case in tropical countries like India. The dust gets accumulated on the front surface of the module and blocks the incident light from the sun. It reduces the power generation capacity of the module. The power output reduces as much as by 50% if the module is not cleaned for a month. In order to regularly clean the dust, a sun tracking- cum- cleaning system has been designed, which not only tracks the sun but also cleans the modules automatically. This automated system is implemented using microcontroller which controls the stepper motor coupled solar panel. This mechanism does not require any sensor or synchronization for tracking the sun. In this mechanism, the solar panels make a rotation of 360o in a day, which results in sliding of cleaning brushes twice over the PV modules. In terms of daily energy generation, the presented tracking- scheme provides about 30% more energy output as compared to the flat PV module (module kept stationary on ground) and about 15% more energy output as compared to PV module with single axis tracking. The implementation and working of 360 degree sun tracking system with automatic cleaning is described in this paper.
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    Secure and Verifiable Policy Update Outsourcing for Big Data Access Control in Cloud
    (2016-07-22T08:36:33Z) Saurabh, Kumar; Shahn, Sayeed; Shariq, Hussain; Shubham, Saraf
    Nowadays the number of users in cloud computing are increasing enormously due to its advantage of providing flexible storage requirement. Due to the high volume and velocity of big data, it is an effective option to store big data in the cloud. Attribute-Based Encryption (ABE) is a capable technique to ensure the end-to-end security of big data in the cloud. However, the policy updating has always been a challenging issue when ABE is used to construct access control schemes. A trivial implementation is to let data owners retrieve the data and re-encrypt it under the new access policy, and then send it back to the cloud. This method, however, incurs a high communication overhead and heavy computation burden on data owners. In this project, a novel scheme is proposed that enables efficient access control with dynamic policy updating for big data in the cloud. It also focuses on developing an outsourced policy updating method for ABE systems. This method can avoid the transmission of encrypted data and minimize the computation work of data owners, by making use of the previously encrypted data with old access policies. Moreover, it proposes a policy updating algorithms for different types of access policies. Finally, an efficient and secure method is developed that allows data owner to check whether the cloud server has updated the cipher texts correctly. The analysis shows that our policy updating outsourcing scheme is correct, complete, secure and efficient.