Advanced image steganography based on exploiting modification direction and neutrosophic set

A new variant of image steganography based on exploiting modification directions (EMD) named advanced EMD (AEMD) is introduced. In this method the secret digits in mⁿ -ary notional systems are embedded into a group of n pixels of the cover image. To increase data hiding capacity, edge masking characteristics of human visual system is exploited to embed more bits at image edge pixels than non-edge pixels. To do this, a neutrosophic set edge detector, named as MNSED is also introduced to classify cover image into 2?×?2 non-overlapping edge and non-edge blocks without any overhead information. Hence the secret digits in two different bases are embedded into the edge and non-edge blocks. Experimental results show that the proposed method provides higher embedding capacity and better quality compared to the existing schemes, while its resistance to steganographic attack is still higher.

     

Heterogeneous video transcoding to lower spatio-temporalresolutions and different encoding formats

In this work, transcoding of pre-encoded MPEG-1, 2 video into lower bit rates is realized through altering the coding algorithm into H.261/H.263 standards with lower spatio-temporal resolutions. For this heterogeneous transcoding, we extract and compose a set of candidate motion vectors, from the incoming bit stream, to comply with the encoding format of the output bit stream. For the spatial resolution reduction we generate one motion vector out of a set of input motion vectors operating on the higher spatial resolution image. Finally, for the temporal resolution reduction we compose new motion vectors from the dropped frames motion vectors. Throughout the paper, we discuss the impact of motion estimation refinement on the new motion vectors and show that for all cases a simple half-pixel refinement is sufficient for near-optimum results     

Extracting a general iterative method from an Adomian decomposition method and comparing it to the variational iteration method

In this work, a new form of Adomian decomposition method (ADM) is presented; by this form a general iterative method can be achieved in which there is no need of calculating Adomian polynomials. Also, this general iterative method is compared with the Adomian decomposition method and variational iteration method (VIM) and its advantages are expressed.     

Improvement parameters in dynamic compaction adjacent to the slopes

Dynamic compaction is a cost-effective method commonly used for improvement of sandy soils.A number of researchers have investigated experimentally and numerically the improvement parameters of soils using dynamic compaction,such as crater depth,improvement depth,and radial improvement,however,these parameters are not studied for improvement adjacent to the slopes or trenches.In this research,four different slopes with different inclinations are modeled numerically using the fi nite element code ABAQUS,and impact loads of dynamic compaction are applied.The static factors of safety are kept similar for all trenches and determined numerically by application of gravity loads to the slope using strength reduction method(SRM).The analysis focuses on crater depth and improvement region which are compared to the state of fl at ground.It can be observed that compacted area adjacent to the slopes is narrower and slightly away from the slope compared to the fl at state.Moreover,crater depth increases with increase in slope inclination.     

Packet prioritization for H.264/AVC video with cyclic intra-refresh line

Insertion of a cyclic intra-refresh line is a lightweight way of mitigating spatio-temporal error propagation in a video stream transmitted over a mobile network. This paper presents low-complexity yet effective prioritization based on slice position within a video frame relative to the cyclic refresh line. Two prioritization schemes are compared. The first is a region-based method, while the second, which is packet-based, improves packet classification. Experimental results indicate that, the packet-based scheme can achieve video quality gains of up to 4 dB, compared to when the scheme is not used. The proposed schemes require no decoder modifications and do not introduce an increase in bitrate or in computational complexity.     

Effect of Resonant Helical Field (RHF) on Runaway Electrons in Tokamaks

The high energy current of runaway electrons during a major disruption in tokamak reactors can cause serious damage to the first wall of the reactor and reduce its life time. Therefore, finding a method to minimize runaway electron is much needed. Resonant helical field (RHF) is one of the methods for controlling the magnetohydrodynamic (MHD) activity. This paper attempts to examine the effect of RHF on the generation of runaway electrons. Main parameters such as plasma current, loop voltage, emitted hard X-ray intensity, MHD oscillation, H_α radiation and MHD activity modes, in the presence and absence of RHF (L = 2 and L = 3), were measured. The results show that applying this system can change runaway electrons generation.     

The impact of tree structures on the performance of zerotree-based wavelet video codecs

In this paper we analyze the impact of tree structures on the performance of zerotree-based wavelet video codecs. Since zerotree approach is based on aggregation of insignificant coefficients in trees, therefore design of a tree structure is the key issue for a better performance. We have considered six different tree structures with characteristics varying from a simple to relatively complex and composite tree structures to code the luminance–chrominance components of a video sequence. Their performances are compared in terms of average number of bits generated per bitplane, number of coded bitplanes for a given bit budget, rate-distortion performance, memory requirements and computational complexity. We observe that in general more complex and longer trees do not necessarily improve the coding efficiency. However, the tree structures encapsulating more elements per tree are memory efficient. Therefore, the rate-distortion performance, memory requirements and computational complexities need to be traded-off while selecting a particular tree structure. It is also observed that the additional improvement due to optional entropy coding is also tree structure dependent. Further, the simulation results show that by designing an efficient tree structure, depending on the picture content, the performance of a video coder can be improved by up to 2.0 dB, while reducing the computational complexity by 45–60% as well as the memory requirements by almost 29–35%. Compared to the standard JPEG2000 (for intra-frame), tree-based coders are found to be efficient in terms of coding and complexity, particularly at lower bit rates.     

Valuable Nutrients and Functional Bioactives in Different Parts of Olive (Olea europaea L.)-A Review

The Olive tree (Olea europaea L.), a native of the Mediterranean basin and parts of Asia, is now widely cultivated in many other parts of the world for production of olive oil and table olives. Olive is a rich source of valuable nutrients and bioactives of medicinal and therapeutic interest. Olive fruit contains appreciable concentration, 1-3% of fresh pulp weight, of hydrophilic (phenolic acids, phenolic alchohols, flavonoids and secoiridoids) and lipophilic (cresols) phenolic compounds that are known to possess multiple biological activities such as antioxidant, anticarcinogenic, antiinflammatory, antimicrobial, antihypertensive, antidyslipidemic, cardiotonic, laxative, and antiplatelet. Other important compounds present in olive fruit are pectin, organic acids, and pigments. Virgin olive oil (VOO), extracted mechanically from the fruit, is also very popular for its nutritive and health-promoting potential, especially against cardiovascular disorders due to the presence of high levels of monounsaturates and other valuable minor components such as phenolics, phytosterols, tocopherols, carotenoids, chlorophyll and squalene. The cultivar, area of production, harvest time, and the processing techniques employed are some of the factors shown to influence the composition of olive fruit and olive oil. This review focuses comprehensively on the nutrients and high-value bioactives profile as well as medicinal and functional aspects of different parts of olives and its byproducts. Various factors affecting the composition of this food commodity of medicinal value are also discussed.