A image encryption algorithm based on chaotic Lorenz system and novel primitive polynomial S-boxes

We have proposed a robust, secure and efficient image encryption algorithm based on chaotic maps and algebraic structure. Nowadays, the chaotic cryptosystems gained more attention due to their efficiency, the assurance of robustness and high sensitivity corresponding to initial conditions. In literature, there are many encryption algorithms that can simply guarantees security while the schemes based on chaotic systems only promises the uncertainty, both of them can not encounter the needs of current scenario. To tackle this issue, this article proposed an image encryption algorithm based on Lorenz chaotic system and primitive irreducible polynomial substitution box. First, we have proposed 16 different S-boxes based on projective general linear group and 16 primitive irreducible polynomials of Galois field of order 256, and then utilized these S-boxes with combination of chaotic map in image encryption scheme. Three chaotic sequences can be produced by the disturbed of Lorenz chaotic system corresponding to variables x, y and z. We have constructed a new pseudo random chaotic sequence k_i based on x, y and z. The plain image is encrypted by the use of chaotic sequence k_i and XOR operation to get a ciphered image. To show the strength of presented image encryption, some renowned analyses are performed.

     

Application of ceramic film as means of lubrication for forming of Ti sheet in a highly localized deformation process

Incremental forming is a novel die-less sheet forming process. There is a need for special means to retain lubricant at the tool/sheet interface during forming. To fulfillthe stated aim, a porous ceramic film was developed on pure Ti substrate, and it was done through an electrochemical depsition process known as plasma electrolytic oxidation. The film with preferred pore size could be realized after several attempts by varying the processing parameters. In order to characterize the film, a variety of tests including rnicrostructure, film-substrate bond strength and tribological properties tests were conducted. On-job performance of the film was also examined by forming Ti components employing a range of forming conditions. It was found that the proposed method of lubrication was effective, and the plasma eletrolytic oxidation process can be employed to fabricate films on pure Ti sheet to provide means of lubrication during incremental forming.     

Application of Genetic Algorithm in unit selection for Malay speech synthesis system

Corpus based speech synthesis can produce high quality synthetic speech due to it high sensitivity to unit context. Large speech database is embedded in synthesis system and search algorithm (unit selection) is needed to search for the optimal unit sequence. Speech feature which served as target cost is estimated from the input text. The acoustic parameters which served as join cost are derived from mel frequency cepstral coefficients (MFCCs) and Euclidean distance. In this paper, a new method which is Genetic Algorithm is proposed to search for optimal unit sequence. Genetic Algorithm (GA) is a population based search algorithm that is based on the biological principles of selection, reproduction, crossover and mutation. It is a stochastic search algorithm for solving optimization problem. The speech unit sequence that has minimum join cost will be synthesized into complete waveform data.     

Correction to: A dual layer security scheme for medical images using Hessenberg and singular value decompositions

Multimedia Tools and Applications -     

Cryptanalysis and Improvement of Novel Image Encryption Technique Using Hybrid Method of Discrete Dynamical Chaotic Maps and Brownian Motion

Multimedia Tools and Applications - Recently, an encryption technique depending on discrete dynamical chaotic maps and Brownian motion was offered. The authors of the understudy cryptosystem claim...     

A simple void node and loop‐free three‐dimensional routing protocol for multi‐hop wireless networks

Wireless networks are now very essential part for modern ubiquitous communication systems. The design of efficient routing and scheduling techniques for such networks have gained importance to ensure reliable communication. Most of the currently proposed geographic routing protocols are designed for 2D spatial distribution of user nodes, although in many practical scenarios user nodes may be deployed in 3D space also. In this paper, we propose 3D routing protocols for multihop wireless networks that may be implemented in two different ways depending on how the routing paths are computed. When the routing paths to different user nodes from the base station in the wireless network are computed by the base station, we call it centralized protocol (3DMA‐CS). A distributed routing (3DMA‐DS) protocol is implemented when respective routing path of each user node to the base station is computed by the user node. In both of these protocols, the user (base station) selects the relay node to forward packets in the direction of destination, from the set of its neighbours, which makes minimum angle with the reference line drawn from user (base station) to the base station (user), within its transmission range. The proposed protocols are free from looping problem and can solve the void node problem (VNP) of multihop wireless networks. Performance analysis of the proposed protocol is shown by calculating end‐to‐end throughput, average path length, end‐to‐end delay, and energy consumption of each routing path through extensive simulation under different network densities and transmission ranges.     

Simple,secure, and lightweight mechanism for mutual authentication of nodes in tiny wireless sensor networks

Wireless sensor networks (WSNs) are widely used in large areas of applications; due to advancements in technology, very tiny sensors are readily available, and their usage reduces the cost. The mechanisms designed for wireless networks cannot be implied on networks with tiny nodes due to battery and computational constraints. Understanding the significance of security in WSNs and resource constraintness of tiny WSNs, we propose a node authentication mechanism for nodes in wireless sensor networks to avoid security attacks and establish secure communication between them. In the proposed mechanism, a base station (BS) generates a secret value and random value for each sensor node and stores at the node. The sensor node authenticates using secret value and random number. Random nonce ensures freshness, efficiency, and robustness. The proposed mechanism is lightweight cryptographic, hence requires very less computational, communication, and storage resources. Security analysis of the proposed mechanism could not detect any security attack on it, and the mechanism was found to incur less storage, communication, and computation overheads. Hence, the proposed mechanism is best suitable for wireless sensor networks with tiny nodes.     

Performance evaluation of a non-linear error model for underwater range computation utilizing GPS sonobuoys

Deployed from an airborne platform or a surface vessel, arrays of GPS sonobuoys can be used to efficiently track and localize submarines. The range of the target of interest can be monitored with the deployed sonobuoys. However, the accuracy deteriorates when the target is on the detection range of only one sonobuoy. The objective of this research is to improve the range computation of the target of interest by establishing a non-linear error model for range error using adaptive neuro-fuzzy inference systems (ANFIS), which has the capabilities of dealing with data of high level of uncertainty and the advantage of being based on neural computation. Furthermore, the performance of the proposed model is examined with both experimental real field data and contact-level simulation data considering different scenarios for both the array of GPS sonobuoys and the target. The results discuss merits and the limitations of the proposed method.