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Encryption is a technique of encoding data so that they can only be recognized by authorized receivers. More interactive media information is communicated in the medical, business, and military fields because of the rapid advances in various multimedia transmission and networking technologies, which may contain sensitive information that must be kept hidden from public users. Advanced encryption standards (AES) and data encryption standards (DES) are widely used encryption algorithms for text data. However, they are not appropriate for video data. To ensure that this information cannot be accessed by attackers, the demand for efficient video-protection techniques has been raised. This article provides multimedia design requirements to maintain a secure multimedia system occupied with a threat model for detecting and ranking the potential risks facing a multimedia system. the risks exposed to multimedia security and their impacts on users are typically described according to the textual description and also an overview of the current state-of-the-art video-encryption schemes are presented and their performance parameters have been examined. The relationship between encryption algorithms and compression techniques is also discussed and various multimedia applications have been presented in this paper; Additionally, as the synchronisation of real-time continuous streams is necessary for the interchange of these streams in multimedia conferencing services, multiple synchronisation strategies have been given in this study along with video synchronisation challenges.

Quantum cryptography utilizes the quantum properties of photons to construct an unbreakable crypto-algorithm in real-time. In this paper, based on quantum and classical computation principles, a new quantum encryption algorithm using the symmetric key is presented. It is a block-cipher algorithm which means that each message contains blocks in which 4 bits for each. Firstly, keyed rotations and permutation of the message bits are used. Secondly, the encrypted message is converted to qubits then several dynamic quantum gates are applied to them key dependently to make the ciphertext state reach the state of non-orthogonality. In consequence of the principles of quantum mechanics, the eaves cannot distinguish the non-orthogonal states of the encrypted message. The proposed algorithm is proofed to increase the message space, the various algorithm analysis proofed that our proposed algorithm has an improved strength against various attacks, including the brute force attack.

Quantum cryptography appropriates the features of photons to create a secured algorithm in real-time. In this study, a new algorithm is illustrated using the symmetric key based on the basics of quantum and classical computation. In this algorithm, the message contains blocks, the space of each block is 16 bits. First, the classical encryption process depends on the key that makes rotation and permutation in the bits of block message. Second, the bits of encrypted block messages are converted to qubits. Third, Pauli gates are used, and applies the output of the second stage to them depends on a key to achieving the non-orthogonality of ciphertext states. Because of the basis of quantum computing, the eavesdroppers cannot detect the encrypted message states that changed to non-orthogonal states. The proposed algorithm is proven to increase the message space, the various algorithm analysis proofed that our proposed algorithm has an improved strength against various attacks, including the brute force attack.

Electronic commerce, as exemplified by the popularity of the Internet, is becoming more important along with fast progress in communications and information technology. The SET (Secure Electronic Transaction) protocol is a scheme designed to ensure that merchants and cardholders can conduct business over a public network. Although the SET protocol has some disadvantages, but still it is the most commonly used protocol in the Internet shopping. Signcryption is a cryptographic primitive which simultaneously provides both confidentiality and authenticity in a single logical step. Signcryption based on elliptic curves provides the same level of security using smaller keys compared to schemes based on the discrete logarithm problem over finite fields. This paper examines the benefits of using signcryption rather than signaturethen-encryption in the SET protocol. Using identity-based signcryption in the SET protocol reduces the number of encryption and decryption operations. Moreover, signcryption is less time consuming than signature-then-encryption.

Electrical stimulation optimization is a challenging problem. Even when a single region is targeted for excitation, the problem remains a constrained multi-objective optimization problem. The constrained nature of the problem results from safety concerns while its multi-objectives originate from the requirement that non-targeted regions should remain unaffected. In this paper, we propose a mixed integer linear programming formulation that can successfully address the challenges facing this problem. Moreover, the proposed framework can conclusively check the feasibility of the stimulation goals. This helps researchers to avoid wasting time trying to achieve goals that are impossible under a chosen stimulation setup. The superiority of the proposed framework over alternative methods is demonstrated through simulation examples.

In this article, a novel approximate analytical solution is presented for solving the standard viral dynamic model. Basically, the standard model is used to study viral dynamics in patients for a wide range of viruses like HIV, HPV, HBV, and HCV. In this research work, the standard model for hepatitis C virus (HCV) is considered in detail; however, the analysis and results can be applicable for all other viruses. This standard model is used to study viral dynamics in patients treated with direct-acting antiviral agents (DAAs). Power series solution combined with Laplace–Padé resummation method (PSLP) is used to obtain the approximate analytical solutions for the model. To test the capability as well as the validity of the proposed method, results are compared with available viral load data published in the literature and with published simulation results. Good fits are obtained in the comparison for all cases considered. Given that medical specialists and physicians are more interested in solutions that yield direct and simple predictions, it is expected that the proposed approximate analytical solution would be attractive to them and help them to obtain a straightforward and a proper estimation regarding the viral load due to variations in treatment and/or patient’s parameters.

This paper presents a new approach for secure hiding of textual data in a colored digital image. Use of images as a cover media in steganography is based on the deficiencies in the human visual system (HVS). The proposed technique employs two independent chaotic sequences for specifying the locations where the message bits are embedded in the cover image using an adapted version of the least significant bit (LSB) method. Message bits are embedded using the 3-3-2 LSB insertion method for the chaotically selected pixels of the cover image. This technique provides sufficient security as the same sequence of numbers cannot be generated without knowing the exact key; that is; the initial conditions of the two chaotic maps used in the index selection process. Moreover, the preliminary results ensure that eavesdroppers will not have any suspicion that there is a message hidden within the sent image since the peak signal to noise ratio (PSNR) is high and the mean-squared-error (MSE) is low. Furthermore, the length of the secret message is another important component of the key, which standard steganography detection methods cannot estimate correctly. Finally, the proposed approach provides better PSNR values and MSE values compared to other existing techniques as apparent from our experimental results.

This paper investigates several alternative schemes for hiding a grayscale image in a colored cover image in the spatial domain. First, we consider the use of one-dimensional (Tent map) versus two-dimensional (Baker's map) chaotic maps for the selection of the set of pixels where the secret message bits are to be embedded. The red color channel of the cover image for the formerly selected pixels is affected by the embedding process since the eye is not very sensitive for slight variations in this color channel. Next, two LSB embedding schemes are examined; namely, embedding one bit per pixel and embedding two bits per pixel. The preliminary results ensure that, to eavesdroppers, there will be almost no suspicion regarding the existence of a secret message hidden within the sent image since the peak-signal-to-noise-ratio (PSNR) is high and the mean-squared-error (MSE) is low for the different alternatives investigated. However, there is a clear impact on the time required for the embedding process if two-dimensional maps and/or one bit per pixel LSB technique are used.

is an increased activity in research and development conducted to improve current payment systems in parallel with the progress of Internet. Signcryption combines the functionalities of encryption and digital signing in a single logical step. It is a cryptographic primitive that provides confidentiality, integrity, authentication and non-repudiation. Identity-based cryptography serves as an efficient alternative to the traditional certificate-based cryptosystems. This paper introduces an efficient electronic payment system based on signcryption without bilinear pairings. This e-cash system is more efficient than other schemes employing bilinear pairings and involves less computational cost. In the proposed protocol, the token is issued and authenticated by the bank to prevent double spending problem. The customer delegates his signing capability to the merchant. The bank verifies the identities of both the original signer (customer) and the proxy signer (merchant) and ensures the originality of the transaction. Unlike the existing e-payment systems, the problem of double spending of e-cash does not arise because each transaction is made uniquely identifiable. Hence, no separate protocol is needed to check double-spending. The performance and the security analysis of the proposed e-cash system are discussed revealing its strength from the viewpoint of security and efficiency with regard to computations required.

paper introduces a new authentication protocol using the tripartite signcryption scheme without bilinear pairings that provides confidentiality and authentication between three entities. Mobile communication seems very attractive to users as well as operators and service providers. However, despite of its numerous advantages, mobile communication has been facing many security problems. In this paper, it is demonstrated how the proposed tripartite signcryption scheme can be used to provide authentication and to guarantee secure communication. The use of the proposed tripartite signcryption scheme helps reduce the signaling overhead compared to the scheme in (1).

key establishment protocol allows entities to establish a common secret key to ensure secure communications over an insecure public network. This paper proposes two new two- party key agreement protocols. Both protocols do not involve bilinear pairings. The first protocol is a certificate-based key agreement protocol that is more efficient than (1) due to its dependence on the elliptic curve discrete logarithm problem and the second is an extension to a certificateless key agreement protocol. Both protocols depend on the use of an authentication message to check that the shared session key is equal for both entities before using it. This authentication message prevents the key off-set attack that is valid for the Haiyan-Sun protocol (2). The security analysis of the second protocol is discussed. The proposed certificateless key agreement protocol is compared with other protocols in literature (2,3,4) and it requires minimal computational cost. Moreover, this protocol is implemented using the Mathematica (7) program.

Effective utilization plans for various resources at a container terminal are essential to reducing the turnaround time of cargo vessels. Among the scarcest resources are the berth and its associated cranes. Thus, two important optimization problems arise, which are the berth allocation and quay crane assignment problems. The berth allocation problem deals with the generation of a berth plan, which determines where and when a ship has to berth alongside the quay. The quay crane assignment problem addresses the problem of determining how many and which quay crane(s) will serve each vessel. In this paper, an integrated heuristics-based solution methodology is proposed that tackles both problems simultaneously. The preliminary experimental results show that the proposed approach yields high quality solutions to such an NP-hard problem in a reasonable computational time suggesting its suitability for practical use.

Achieving confidentiality and authentication in e-commerce transactions are among the primary security goals. In this paper, a new cryptographic scheme is proposed which guarantees the authenticity of the customer and ensures the confidentiality of the communications among the bank, the merchant and the customer. The proposed solution is the use of a tripartite signcryption scheme with low computational and communications overhead. A variant of the proposed scheme that enables a firewall to authenticate the origin of the ciphertext without disclosure of the contents of the original plaintext message is also presented. General Terms

Signcryption is a cryptographic primitive which simultaneously provides both confidentiality and authenticity in a single logical step. In a proxy signature scheme, an original signer delegates his signing power to a proxy agent, who signs a message on behalf of him. This paper introduces a new proxy signcryption scheme based on the Discrete Logarithm Problem (DLP) with a reduced computational complexity compared to other schemes in literature. In this proposed scheme, the receiver is the only one who can verify the origin of the ciphertext. Moreover, in this scheme, an authorized proxy signcrypter can create valid proxy signatures after verifying the identity of the original signcrypter. The proposed scheme achieves the various desirable security requirements. An elliptic curve based version of the proposed proxy signcryption scheme has been implemented using Mathematica for realistic (256-bit) parameters to emphasize the ease of its practical use.

This paper implements a mixed-integer quadratically constrained convex optimization program on distribution networks that have a radial structure topology for denigration of system's real power loss. The adopted mathematical model has been solved using Cplex optimization software. The global optimality of the obtained solution is guaranteed via convex relaxation of the continuous decision variables. This overcomes a major disadvantage of using artificial intelligence techniques, specifically meta-heuristic ones, that give no assurance on the solution quality or the optimality gap. Moreover, exact representation of the network losses through the assessment of the objective's function numerical-value is obtained. This overcomes the drawbacks of using linear approximations to power flow equations. The proposed algorithm has been evaluated on two IEEE standard systems and a realistic-sized network with a comparative study with other existing algorithms in the literature.

The use of standardized containers in cargo transportation has gained undoubted worldwide importance during the last four decades. At a container terminal, containers are transferred between vessels and container yard blocks by different types of transporters. Improving transporter utilization can lead to improving terminal throughput and operational efficiency. This is why dual-cycle transfer mode is applied. In dual-cycle transfer mode, transporters operate in a pool serving several cranes in alternative modes of loading or discharging. Although empty travel distance can be reduced, it is difficult to apply dual-cycle transfer mode at manned container terminals. Grouping of transporters can combine ease of use and dual-cycle transfer mode, where transporters in the same group operate in a pool. In this paper, a Multi-Layer Genetic Algorithm (MLGA) is developed to first construct groups of transporters, and then schedule transporters in the same pool in a dual cycle mode of transfer. The decision aims to decrease the makespan of discharging and loading of containers.

Signcryption is a well-known cryptographic primitive that achieves various security goals including confidentiality of communications, source authentication, and integrity of message contents and ensuring non-repudiation. In e-cash systems, customers prefer to spend their e-coins anonymously. Blind signatures have been developed to meet this requirement. In the present paper, two new blind signcryption schemes are proposed in order to combine the functionalities of both primitives in a single logical step. The first one is tailored for traditional public key infrastructures; while the second one is an identity-based scheme. The proposed schemes have been designed with an eye on applications to e-cash systems and thus overcoming shortcomings in earlier attempts in blind signcryption. The two schemes are computationally efficient promoting their use in practical scenarios. The schemes involve three parties. In e-cash scenarios, these are the bank, the e-coin acquirer (customer) and the merchant which deposits the e-coin in his bank account.

Signcryption combines the functionalities of encryption and digital signing in a single logical step in order to obtain confidentiality, integrity, authentication and non-repudiation. It is more efficient than the sign-then-encrypt approach. Identity-based cryptography serves as an efficient alternative to the traditional certificate-based cryptosystems. The idea of identity-based cryptography is to enable a user to use any arbitrary string that uniquely identifies him as his public key. This paper proposes two new schemes. The first scheme involves a single recipient and the second is its extension in the multi-receiver setting. Both schemes outperform other schemes in literature as they do not involve any bilinear pairings in neither signcryption nor verification phases. Moreover, both satisfy various desirable security properties.