Construction of S-box based on chaotic Boolean functions and its application in image encryption

In numerous encryption frameworks, the first information is changed into encoded form by applying nonlinear substitutions and affecting diffusion. The goal of the nonlinear change is to accomplish high level of randomness in the image content. The choice of the source of randomness is critical because the success in cryptanalysis is demarked by the characteristics identified in the encrypted data. The chaotic frameworks show random conduct that is suitable for encryption applications where nonlinear transformations are needed in the middle of plaintext and the scrambled information. The application of nonlinear functional chaos-based system with embedded chaotic systems and binary chaotic sequences can prompt randomness and diffusion in the information. In addition to the high state of randomness, the requirement for various round keys is needed in a run of the mill substitution–permutation process. The proposed strategy kills the requirement for different round keys, which is suitable for high-speed communication frameworks. The measurable analyses performed on the proposed nonlinear algorithm which show improvement in encryption quality and safety against numerous brute-force and statistical attacks. Also, the proposed framework demonstrates high safety against differential and linear cryptanalysis.     

A novel analytical solution of a fractional diffusion problem by homotopy analysis transform method

In this study, we present the homotopy analysis transform method for finding solution of fractional diffusion-type equations. We can attain these equations by substituting a first-order time derivative by a fractional-order derivative in regular diffusion equation. We add some examples in order to illustrate the usefulness and efficiency of our novel proposed technique for fractional diffusion equations.     

A method to extend the spectral iteration technique

A method has been developed to extend the spectral iteration technique to encompass a more general class of subdomain type basis functions. While retaining the advantages of the spectral iteration technique, this method enables the usage of basis functions other than piecewise constant basis functions in expressing the unknown current distribution. Advantages of this technique with the choice of piecewise sinusoidal basis functions as compared to piecewise constant basis functions have been demonstrated for both antenna and scattering problems. This choice of basis functions is found to result in a further reduction in the number of unknowns required to represent the current distribution. Numerical results of the input impedance for a cylindrical antenna and the scattering cross section of a thin fiat plate are presented and discussed.     

Data Storage for Adaptive Meteor Scatter Communication

Adaptive meteor scatter communication requires a data storage which can transmit or receive data at a continuously variable rate. Several systems, designed around head-per-track rotating memories and shift register arrays, are discussed.     

Control of Distributed Processes

Cost-effective control of distributed computing systems requires practical models for reassigning program modules among the processors in real time.     

Towards Novel Treatments for Schizophrenia: Molecular and Behavioural Signatures of the Psychotropic Agent SEP-363856

Schizophrenia is a complex psychopathology whose treatment is still challenging. Given the limitations of existing antipsychotics, there is urgent need for novel drugs with fewer side effects. SEP-363856 (SEP-856) is a novel psychotropic agent currently under phase III clinical investigation for schizophrenia treatment. In this study, we investigated the ability of an acute oral SEP-856 administration to modulate the functional activity of specific brain regions at basal levels and under glutamatergic or dopaminergic-perturbed conditions in adult rats. We found that immediate-early genes (IEGs) expression was strongly upregulated in the prefrontal cortex and, to a less extent, in the ventral hippocampus, suggesting an activation of these regions. Furthermore, SEP-856 was effective in preventing the hyperactivity induced by an acute injection of phencyclidine (PCP), but not of d-amphetamine (AMPH). The compound effectively normalized the PCP-induced increase in IEGs expression in the PFC at all doses tested, whereas only the highest dose determined the major modulations on AMPH-induced changes. Lastly, SEP-856 acute administration corrected the cognitive deficits produced by subchronic PCP administration. Taken together, our data provide further insights on SEP-856, suggesting that modulation of the PFC may represent an important mechanism for the functional and behavioural activity of this novel compound.     

Analysis of reactivity induced accidents at Pakistan Research Reactor-1

Analysis of reactivity induced accidents in Pakistan Research Reactor-1 (PARR-1) utilizing low enriched uranium (LEU) fuel, has been carried out using standard computer code PARET. The present core comprises of 29 standard and five control fuel elements. Various modes of reactivity insertions have been considered. The events studied include: start-up accident; accidental drop of a fuel element on the core; flooding of a beam tube with water; removal of an in-pile experiment during reactor operation etc. For each of these transients, time histories of reactor power, energy released and clad surface temperature etc. were calculated. The results reveal that the peak clad temperatures remain well below the clad melting temperature during these accidents. It is concluded that the reactor, which is operated safely at a steady-state power level of 10 MW, with coolant flow rate of 950 m³/h, will also be safe against any possible reactivity induced accident and will not result in a fuel failure.