P. Visalakshi ¹, Devashish Sood ¹, S. Priya ¹

Affiliations
1 Department of Computer Science and Engineering SRM University, Kattankulathur campus, Kancheepuram District - 603 203, Tamil Nadu, IN

Abstract

Objective: We propose a decentralized access controlled scheme for secure data storage in clouds that supports public key encryption. Our scheme also has the added feature of generating attribute key-value pairs with ciphers for easily granting permission to transfer data. The scheme prevents tampering by performing integrity checks and verifying the message digest. Methods/Statistical Analysis: In the proposed scheme, the data is transferred by public key encryption among users by the RSA algorithm. The attributes are sent via e-mail and can trigger an encrypted transfer of data stream, which can be decrypted only by the validated users. The cloud does not store the private keys of users and only stores public keys. Findings: The computation and transfer of cipher text, and storage overheads are the same as a centralized scheme. The decentralization of data makes it private and the encrypted copy on the cloud provides a redundant backup which cannot be read by the cloud. The performance of the scheme has been measured by time complexity of the operations using big-O notation. Applications/Improvement: The scheme can be improved with signatures. Signatures can be studied in detail and come in various types. Some signatures verify the authenticity of files while other complex ones work with multi-party authentication.

Keywords

Access Control in Cloud, Cryptography, MVC, RSA.

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S. Priya ¹, A. Suresh ¹, M. R. Rashmi ²

Affiliations
1 Department of Electrical and Electrical Engineering, S. A. Engineering College, Chennai-600054, Tamil Nadu, IN
2 Amita Vishwa Vidyapeetham, School of Egineering, Bangalore-560055, Karnataka, IN

Abstract

Objective: This work discusses with Direct Torque Control (DTC) of Induction motor using 7 Level NPC Multilevel inverter for reducing the complexity in conventional DTC method. Methods: The limitation of traditional DTC scheme is more distortion in torque profile and the mean torque output never meets the torque demand. To get better performance of the traditional DTC a Space Vector Modulation (SVM) technique is projected to meet the torque and flux demands at low speeds. Findings: By designing 7 level NPC for DTC of induction motor and thereby simplifying the classical DTC method and in very particular this paper is minimizing the complications in Torque and Flux control at minimal speeds by decoupling the torque and flux controls and also reduces the ripples in current and torque profile. 7 level NPC is introduced in this paper which helps in eliminating the torque disturbances into minimum. The proposed 7 level inverter uses less number of switches and neutral-point fluctuations are absent in this model. Detached DC supplies are employed for the DC links which carries the ripple current. The proposed inverter topology provided the required magnitudes and phases of voltage and current vectors to meet the desired load values with fewer harmonic content due to superior level inverter and less distortion in torque profile obtained in the closed loop DTC technique. 1 The DTC of Induction Motor simulated by implementing the SVM technique using 7 level NPC and the simulation results are experimentally validated. Improvements: The steady state torque and speed output have less ripple content which reduces the oscillation with a quick response at steady state was investigated.

Keywords

Direct Self Control (DSC), Direct Torque Control (DTC), Multilevel Level Inverter ( MLI), Neutral Point Clamped(NPC), Space Vector Modulation (SVM).

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P. Visalakshi ¹, Ishaan Jindal ¹, Namita Sahu ¹, S. Priya ¹

Affiliations
1 Department of Computer Science and Engineering, SRM University, Kattankulathur Kancheepuram Dist - 603203, Tamil Nadu, IN

Abstract

Objectives: Migration of databases merging the databases the acquisition of organization is the one of the major problems are Integrity, accuracy, business continuity and technical advances for any organization. Methods/Statistical Analysis: At the time of database migration is observed with the effect of the changes in the parameters of the sources and target platform databases. Database capability is maintained by changing the character set and Endian conversion is done if required. Findings: The Oracle cross platform new technology used to transport databases is XTTS which makes transportation is very easy within shorter period of time even though the size of the file is large. The Oracle provides Recovery Manager to convert the data format from one endian format to other endian format. Applications/Improvement: The results of extrapolation for different datasets are done to estimate the relationship between the size of datasets and the required time for migration.

Keywords

Endian Conversion, Migration, Network File Systems (NFS), RMAN, Short Time, XTTS (Cross Platform Transportable Table Space).

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