Optimal Image Steganography Content Destruction Techniques

The paper presents two approaches for destroying steganogrphy content in an image. The first is the overwriting approach where a random data can be written again over steganographic images whereas the second approach is the denoising approach. With the second approach two kinds of destruction techniques have been adopted these are filtering and discrete wavelet techniques. These two approaches have been simulated and evaluated over two types of hiding techniques, Least Significant Bit LSB technique and Discrete Cosine Transform DCT technique. The results of the simulation show the capability of both approaches to destroy the hidden information without any alteration to the cover image except the denoising approach enhance the PSNR in any received image even without hidden information by an average of 4dB.

Climate Influence in Dendrochronological Series of Araucaria angustifolia from Campos do Jordão, Brazil

A dendrochronological series of Araucaria angustifolia was analyzed for a better understanding of the climatic factors that operate in Campos do Jordão city, São Paulo state, Brazil. The dendroclimatic analysis was carried out using 45 samples from 16 Araucaria angustifolia trees to reconstruct the precipitation and the temperature over the 1803–2012 yearly interval. To this end, Pearson’s correlation was calculated between mean chronology and the climatic time series using a monthly temporal resolution to calibrate our models. We obtained correlations as high as r=0.22(α=0.1) for precipitation (February), and r=0.21(α=0.1) for temperature (March), both corresponding to the end of the summer season. Our results show evidence of temporal instabilities because the correlations for the halves of 1963–2012 were very different, as well as for the full period. To overcome this problem, the dendrochronological series and the climatic data were investigated using the wavelet techniques searching for time-dependent cause–effect relationships. From these analyses, we find a strong influence of the region’s precipitation and temperature on the growth of tree ring widths.

Wavelet OFDM for Power Line Communication

Power Line Communication (PLC) system offers cheaper mode of signal communication facilities. In fast Fourier transform (FFT) based multicarrier PLC system, a cyclic prefix (CP) of the same length of the channel impulse response is added to each symbol in order to transmit data. As a result, there is always an inherent wastage of bandwidth and resources. This research presents a wavelet transform based orthogonal frequency division multiplexing (WTOFDM) approach that eliminates the need for these cyclic prefix and improves the efficiency of the PLC transmission. The presented PLC model is designed for faster and efficient transmission over the power line. The obtained results indicate that the proposed approach enhances the transmission throughput; provides better performance for impulsive noise, and increases the efficiency of the PLC system as a whole. In the end a performance comparison of different wavelet techniques have also been incorporated.

Wavelet OFDM for Power Line Communication

Power Line Communication (PLC) system offers cheaper mode of signal communication facilities. In fast Fourier transform (FFT) based multicarrier PLC system, a cyclic prefix (CP) of the same length of the channel impulse response is added to each symbol in order to transmit data. As a result, there is always an inherent wastage of bandwidth and resources. This research presents a wavelet transform based orthogonal frequency division multiplexing (WTOFDM) approach that eliminates the need for these cyclic prefix and improves the efficiency of the PLC transmission. The presented PLC model is designed for faster and efficient transmission over the power line. The obtained results indicate that the proposed approach enhances the transmission throughput; provides better performance for impulsive noise, and increases the efficiency of the PLC system as a whole. In the end a performance comparison of different wavelet techniques have also been incorporated.

A Wavelet-Based Method for the Impact of Social Media on the Economic Situation: The Saudi Arabia 2030-Vision Case

In the present paper, a wavelet method is proposed to study the impact of electronic media on economic situation. More precisely, wavelet techniques are applied versus classical methods to analyze economic indices in the market. The technique consists firstly of filtering the data from unprecise circumstances (noise) to construct next a wavelet denoised contingency table. Next, a thresholding procedure is applied to such a table to extract the essential information porters. The resulting table subject finally to correspondence analysis before and after thresholding. As a case of study, the KSA 2030-vision is considered in the empirical part based on electronic and social media. Effects of the electronic media texts about the trading 2030 vision on the Saudi and global economy has been studied. Recall that the Saudi market is the most important representative market in the GCC continent. It has both regional and worldwide influence on economies and besides, it is characterized by many political, economic and financial movements such as the worldwide economic NEOM project. The findings provided in the present paper may be applied to predict the future situation of markets in GCC region and may constitute therefore a guide for investors to decide about investing or not in these markets.

The spherical-wavelet techniques for RT simulation and analysis

<p class="p1">The spherical wavelet based on the lifting scheme is introduced for adaptive discrete-ordinate sampling of the radiation fields, particularly,<span class="Apple-converted-space">  </span>in the radiative transfer computation using iterative schemes. The lifting scheme for wavelet transform is described from an implementation point of view, including the construction of hierarchical geodesic grids on the sphere and wavelet constructions. In addition, we compare the method with the conventional spherical harmonics, numerically investigating the transformation error and efficiency. The transformation matrices are built in the least-squares sense. The results demonstrate the feasibility of using spherical wavelets as an adaptive discrete-ordinate sampling method at the cost of O(N), where N is the number of significant coefficients. </p>