The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Muhammad Rafiq Abuturab - One of the best experts on this subject based on the ideXlab platform.

  • an asymmetric single channel color image encryption based on hartley transform and gyrator transform
    Optics and Lasers in Engineering, 2015
    Co-Authors: Muhammad Rafiq Abuturab
    Abstract:

    Abstract A novel asymmetric single-channel color image encryption using Hartley transform and gyrator transform is proposed. A color image is segregated into R , G , and B channels and then each channel is independently Hartley transformed. The three transformed channels are multiplied and then phase- and amplitude truncated to obtain first encrypted image and first decryption key. The encoded image is modulated with a conjugate of random phase mask. The modulated image is gyrator transformed and then phase- and amplitude truncated to get second encrypted image and second decryption key. The asymmetric (decryption) keys, random phase mask, and transformation angle of gyrator transform serve as main keys. The optoelectronic encryption and decryption systems are suggested. Numerical simulation results have been demonstrated to verify the performance and security of the proposed security system.

  • an asymmetric color image cryptosystem based on schur decomposition in gyrator transform domain
    Optics and Lasers in Engineering, 2014
    Co-Authors: Muhammad Rafiq Abuturab
    Abstract:

    Abstract A new asymmetric cryptosystem using Schur decomposition in gyrator transform (GT) domain is introduced. In this approach, the color image to be encoded is first dissociated into red, green and blue channels and then modulated by multiplying three different random phase masks. The three modulated color channels are combined into one gray image by using convolution. The convoluted image is gyrator transformed. The gyrator spectrum is then amplitude- and phase-truncated. The asymmetric decryption phase keys for red, green and blue channels are generated digitally during the encryption process. The phase-truncated image is divided into U and T parts by Schur decomposition. Finally, U and T parts are independently gyrator transformed to obtain two encoded images, which can be assigned to a joint authorized user (or two authorized users). GT evades optical alignment problems. The Schur decomposition represents an intermediate step in SVD decomposition, and thus requires less number of computations. The multiplication order of Schur decomposition, three transformation angles of GT, and three asymmetric keys are regarded as decryption keys, which boost the degree of security against existing attacks. The proposed encryption process can be carried out digitally, while the decryption process can be realized optically. Numerical simulations prove the validity and security of the proposed approach.

  • color image security system based on discrete hartley transform in gyrator transform domain
    Optics and Lasers in Engineering, 2013
    Co-Authors: Muhammad Rafiq Abuturab
    Abstract:

    Abstract A novel color image encryption algorithm based on Arnold- and discrete Hartley transform in gyrator transform domain is proposed. In this method, a color image is segregated into red, green, and blue channels. Each channel is permutated by first Arnold transform operation and the spatial distribution of pixel value is changed by first discrete cosine transform at image plane. The resulting image is encoded by discrete Hartley transform. The encoded information is again permutated by second Arnold transform and the spatial distribution of pixel value is changed by second discrete cosine transform at frequency plane, and finally gyrator transform is executed. The period and iterative number of Arnold transform, and transformation angles of gyrator transform in each channel are main keys, which increase the security of the proposed system. The proposed method can be well protected under chosen- and known plaintext attacks. Numerical simulations are conducted to illustrate the security, validity, and feasibility of the proposed method.

  • color information security system using arnold transform and double structured phase encoding in gyrator transform domain
    Optics and Laser Technology, 2013
    Co-Authors: Muhammad Rafiq Abuturab
    Abstract:

    Abstract A new method for encoding color information based on Arnold transform and double structured phase encoding in gyrator transform domain is introduced. The phase function of Fresnel zone plate is used as structured phase mask. Prior to the encryption, the decomposed red, green, and blue components of the color image are independently permutated by Arnold transform, transmitted through structured phase mask, and then performed gyrator transform. The system parameters of Arnold transform, structured phase mask, and gyrator transform in each component image provide as encryption keys of the scheme. The proposed system avoids problems arising from misalignment. The optical implementation has also been proposed. Numerical simulations’ results are presented to verify the security, validity, and possibility of the proposed approach.

  • color information cryptosystem based on optical superposition principle and phase truncated gyrator transform
    Applied Optics, 2012
    Co-Authors: Muhammad Rafiq Abuturab
    Abstract:

    A novel asymmetric color information cryptosystem based on an optical coherent superposition method and phase-truncated gyrator transform (GT) is proposed. In this proposal, an original color image is converted into three independent channels, i.e., red, green, and blue. Each channel is separated into a random phase masks (RPM) and a key phase mask (KPM) using a coherent superposition method. The KPM is a modulation of the RPM by the color channel and used as decryption key. The same RPM, which is independent of plaintext, can be chosen for different images of the same size; however, KPMs, which are related to the original color images, are different. The RPM and the KPM are independently gyrator transformed. Then two gyrator spectra are, respectively, phase truncated to obtain two encoded images and amplitude truncated to generate two asymmetric phase keys. The KPM and two phase keys provide asymmetric keys. The transformation angles of the GT give additional keys for each channel and thus offer a high-level robustness against existing attacks. The proposed optical design is free from axial movement. Numerical simulations are demonstrated to verify the flexibility and effectiveness of the proposed method.

Mohammad Ataei - One of the best experts on this subject based on the ideXlab platform.

  • application of analytical hierarchy process to selection of primary crusher
    International journal of mining science and technology, 2014
    Co-Authors: Mohammad Javad Rahimdel, Mohammad Ataei
    Abstract:

    Abstract Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making (MCDM) problem. In this paper, the Analytical Hierarchy Process (AHP) method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyratory crusher was offered as the best primary crusher for the studied mine.

  • Application of analytical hierarchy process to selection of primary crusher
    Elsevier, 2014
    Co-Authors: Mohammad Javad Rahimdel, Mohammad Ataei
    Abstract:

    Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making (MCDM) problem. In this paper, the Analytical Hierarchy Process (AHP) method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyratory crusher was offered as the best primary crusher for the studied mine. Keywords: MCDM, Analytical Hierarchy Process, Primary crusher selection, Golegohar Iron Min

Shutian Liu - One of the best experts on this subject based on the ideXlab platform.

  • image encryption scheme by using iterative random phase encoding in gyrator transform domains
    Optics and Lasers in Engineering, 2011
    Co-Authors: Zhengjun Liu, Chuang Lin, Jingmin Dai, Shutian Liu
    Abstract:

    Abstract An image encryption is discussed based on the random phase encoding method in gyrator domains. An iterative structure of image encryption is designed for introducing more random phases to encrypt image. These random phase functions are generated by a two-dimensional chaotic mapping with the help of computer. The random phases are utilized for increasing the security of this encryption algorithm. In the chaotic mapping relation, the initial value and expression can serve as the key of algorithm. The mapping relation is considered secretly for storage and transmission in practical application in comparison to traditional algorithms. The angle parameter of gyrator transform is an additional key. Some numerical simulations have been given to validate the performance of the encryption scheme.

Mohammad Javad Rahimdel - One of the best experts on this subject based on the ideXlab platform.

  • application of analytical hierarchy process to selection of primary crusher
    International journal of mining science and technology, 2014
    Co-Authors: Mohammad Javad Rahimdel, Mohammad Ataei
    Abstract:

    Abstract Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making (MCDM) problem. In this paper, the Analytical Hierarchy Process (AHP) method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyratory crusher was offered as the best primary crusher for the studied mine.

  • Application of analytical hierarchy process to selection of primary crusher
    Elsevier, 2014
    Co-Authors: Mohammad Javad Rahimdel, Mohammad Ataei
    Abstract:

    Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making (MCDM) problem. In this paper, the Analytical Hierarchy Process (AHP) method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyratory crusher was offered as the best primary crusher for the studied mine. Keywords: MCDM, Analytical Hierarchy Process, Primary crusher selection, Golegohar Iron Min

Hukum Singh - One of the best experts on this subject based on the ideXlab platform.

  • devil s vortex fresnel lens phase masks on an asymmetric cryptosystem based on phase truncation in gyrator wavelet transform domain
    Optics and Lasers in Engineering, 2016
    Co-Authors: Hukum Singh
    Abstract:

    Abstract An asymmetric scheme has been proposed for optical double images encryption in the gyrator wavelet transform (GWT) domain. Grayscale and binary images are encrypted separately using double random phase encoding (DRPE) in the GWT domain. Phase masks based on devil׳s vortex Fresnel Lens (DVFLs) and random phase masks (RPMs) are jointly used in spatial as well as in the Fourier plane. The images to be encrypted are first gyrator transformed and then single-level discrete wavelet transformed (DWT) to decompose LL , HL , LH and HH matrices of approximation, horizontal, vertical and diagonal coefficients. The resulting coefficients from the DWT are multiplied by other RPMs and the results are applied to inverse discrete wavelet transform (IDWT) for obtaining the encrypted images. The images are recovered from their corresponding encrypted images by using the correct parameters of the GWT, DVFL and its digital implementation has been performed using MATLAB 7.6.0 (R2008a). The mother wavelet family, DVFL and gyrator transform orders associated with the GWT are extra keys that cause difficulty to an attacker. Thus, the scheme is more secure as compared to conventional techniques. The efficacy of the proposed scheme is verified by computing mean-squared-error (MSE) between recovered and the original images. The sensitivity of the proposed scheme is verified with encryption parameters and noise attacks.