76 research outputs found

    Development of variable voltage variable frequency drive system for induction motor speed control

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    This project describes the development of a Variable Voltage Variable Frequency (VVVF) system that controls the speed of Induction Motor (IM) at specific speed. Texas Instrument C2000 Microcontroller (TMS320F28335) has been used in this project as the interface between the control design with the IM. The Texas Instrument microcontroller has been combined with the MATLAB/Simulink and the VVVF system as the communication interface for processing the speed control system. The combination between power electronic circuits and microcontroller along with variable voltage variable frequency (VVVF) technique is able to control the target speed of IM. The target value of VVVF is implemented inside Lookup table and has been combined with the Proportional Integral (PI) speed control that generates the signal into the sinusoidal pulse width modulation (SPWM) for inverter operation. The SPWM signal is produced from the microcontroller with the instruction from MATLAB/Simulink, where the controller performs the output of the motor speed. The PI speed control receives the output of a closed loop feedback system from the motor speed and the error signal is reduced to achieve the value of desired speed reference. In the conclusion, the VVVF closed loop system is very useful to control the desired speed of motor at different variable voltage and variable frequency value. As collected for the results, its show, the VVVF with PI speed control can achieve the actual speed for the IM at 1297rpm and 1499rpm when the reference speeds have been set at 1300rpm and 1500rpm respectively. At the end it can be concluded that the VVVF combined with microcontroller have created an ecosystem for speed control that have achieved the objectives

    Cognitive computation of compressed sensing for watermark signal measurement

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    As an important tool for protecting multimedia contents, scrambling and randomizing of original messages is used in generating digital watermark for satisfying security requirements. Based on the neural perception of high-dimensional data, compressed sensing (CS) is proposed as a new technique in watermarking for improved security and reduced computational complexity. In our proposed methodology, watermark signal is extracted from the CS of the Hadamard measurement matrix. Through construction of the scrambled block Hadamard matrix utilizing a cryptographic key, encrypting the watermark signal in CS domain is achieved without any additional computation required. The extensive experiments have shown that the neural inspired CS mechanism can generate watermark signal of higher security, yet it still maintains a better trade-off between transparency and robustness

    An Efficient Digital Image Watermarking Based on DCT and Advanced Image Data Embedding Method

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    Digital image enhancement and digital content or data image secure using DCT and advanced image data embedding method (AIDEM). AIDEM improved robustness based on particle shifting concept is reproduced secure image data and manipulated there’s a robust would like for a digital image copyright mechanism to be placed in secure image data. There’s a necessity for authentication of the content because of the owner. It’s become more accessible for malicious parties to create scalable copies of proprietary content with any compensation to the content owner. Advanced Watermarking is being viewed as a potential goal to the current downside. Astounding watermarking plans are arranged assaults on the watermarked picture are twisted and proposed to give insurance of proprietorship freedoms, information treating, and information uprightness. These methods guarantee unique information recuperation from watermarked information, while irreversible watermarking plans safeguard proprietorship freedoms. This attribute of reversible watermarking has arisen as an applicant answer for the assurance of proprietorship freedoms of information, unfortunate to alterations, for example, clinical information, genetic information, Visa, and financial balance information. These attacks are also intentional or unintentional. The attacks are classified as geometric attacks. This research presents a comprehensive and old method of these techniques that are developed and their effectiveness. Digital watermarking was developed to supply copyright protection and owners’ authentication. Digital image watermarking may be a methodology for embedding some information into digital image sequences, like text image, image data, during this research analysis on image watermarking and attacks on watermarking process time image data, classification of watermarking and applications. We aim to secure image data using advanced image data embedding method (AIDEM) improved robustness based particle shifting concept is reproduced secure image data. To develop compelling digital image watermarking methodology using mat lab tool and reliable and robust

    Digital Watermarking

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    Today2019;s world is digital world. Nowadays, in every field there is enormous use of digital contents. Information handled on INTERNET and MULTIMEDIA NETWORK SYSTEM is in digital form. The copying of digital content without quality loss is not so difficult .Due to this , there are more chances of copying of such digital information. So , there is great need of prohibiting such illegal copyright of digital media. Digital watermarking (DWM) is the powerful solution to this problem. Digital watermarking is nothing but the technology in which there is embedding of various information in digital content which we have to protect from illegal copying. This embedded information to protect the data is embedded as watermark. Beyond the copyright protection, Digital watermarking is having some other applications as fingerprinting, owner identification etc. Digital watermarks are of different types as robust, fragile, visible and invisible. Application is depending upon these watermarks classifications. There are some requirements of digital watermarks as integrity, robustness and complexity

    PSO Based Lossless and Robust Image Watermarking using Integer Wavelet Transform

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    In recent days, the advances in the broadcasting of multimedia contents in digital format motivate to protect this digital multimedia content form illegal use, such as manipulation, duplication and redistribution. However, watermarking algorithms are designed to meet the requirements of different applications, because, various applications have various requirements. This paper intends to design a new watermarking algorithm with an aim of provision of a tradeoff between the robustness and imperceptibility and also to reduce the information loss. This approach applies Integer Wavelet Transform (IWT) instead of conventional floating point wavelet transforms which are having main drawback of round of error. Then the most popular artificial intelligence technique, particle swarm optimization (PSO) used for optimization of watermarking strength. The strength of watermarking technique is directly related to the watermarking constant alpha. The PSO optimizes alpha values such that, the proposed approach achieves better robustness over various attacks and an also efficient imperceptibility. Numerous experiments are conducted over the proposed approach to evaluate the performance. The obtained experimental results demonstrates that the proposed approach is superior compared to conventional approach and is able to provide efficient resistance over Gaussian noise, sal
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