285 research outputs found

    Bitplanes Block Based Exact Image Compression

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    Abstract: In this paper, an exact image compression based on bit-planes blocking is proposed. The proposed algorithm uses two bit codes for block representation. The codes represent the states of Unicode block and non-Unicode. The algorithm considers further division to non-Unicode block. The block division continues until the smallest block size which are kept as residuals. The smallest block size in the study is two by two. The main process of encoding consumed three codes. Subsequent process uses the fourth code for further compression. The resultant file is subject to further exact compression. The compression technique considered in this study is Huffman. The compression-decompression implementation complexity is comparable with the well-known methods. Also, the compression ratio for the algorithm is comparable with well-known methods. The algorithm parallelization is straightforward and dependent on number of planes. Within a plane, the process hardware realization is simple and does on require special hardware

    Face Recognition Using Dct And Neural Micro-Classifier Network

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    Abstract— In this study, a proposed faces recognition methodology based on the neural micro-classifier network. The proposed methodology uses simple well known feature extraction methodology. The feature extraction used is the discrete cosine transformation low frequencies coefficients. The micro-classifier network is a deterministic four layers neural network, the four layers are: input, micro-classifier, counter, and output. The network provide confidence factor, and proper generalization is guaranteed. Also, the network allows incremental learning, and more natural than others. The proposed face recognition methodology was tested using the standard ORL data set. The experimental results of the methodology showed comparative performance

    Bitplanes Block Based Lossy Image Compression

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    Abstract: In a former paper [21], an exact image compression based on bit-planes blocking was proposed. The proposed algorithm uses two bit codes for block representation. The outcome of the encoding process is two streams: Main Bit Stream, MBS and Residual Bit Stream, RBS. The algorithm core is searching for the greatest block of Unicode to encode in main stream and if not found until size of two by two then it will be kept as is in residual stream. In this paper, a lossy version of that algorithm is presented. The change in the base algorithm is in the definition of the unary-code-block is eased to be above certain percent. The percent is varied from plane to another as their contribution to image power varies. The testing of the proposed algorithm shows comparable results. Image degradations seems restorable even for high compression ratios

    Technique for validating remote sensing products of water quality

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    Remote sensing of water quality is initiated as an additional part of the on going activities of the EAGLE2006 project. Within this context intensive in-situ and airborne measurements campaigns were carried out over the Wolderwijd and Veluwemeer natural waters. However, in-situ measurements and image acquisitions were not simultaneous. This poses some constraints on validating air/space-borne remote sensing products of water quality. Nevertheless, the detailed insitu measurements and hydro-optical model simulations provide a bench mark for validating remote sensing products. That is realized through developing a stochastic technique to quantify the uncertainties on the retrieved aquatic inherent optical properties (IOP). The output of the proposed technique is applied to validate remote sensing products of water quality. In this processing phase, simulations of the radiative transfer in the coupled atmosphere-water system are performed to generate spectra at-sensor-level. The upper and the lower boundaries of perturbations, around each recorded spectrum, are then modelled as function of residuals between simulated and measured spectra. The perturbations are parameterized as a function of model approximations/inversion, sensor-noise and atmospheric residual signal. All error sources are treated as being of stochastic nature. Three scenarios are considered: spectrally correlated (i.e. wavelength dependent) perturbations, spectrally uncorrelated perturbations and a mixed scenario of the previous two with equal probability of occurrence. Uncertainties on the retrieved IOP are quantified with the relative contribution of each perturbation component to the total error budget of the IOP. This technique can be used to validate earth observation products of water quality in remote areas where few or no in– situ measurements are available

    The dynamics of liquid slugs forced by a syringe pump

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    Microfluidic processes for chemical synthesis have become popular in recent years. The small scale of the chemical reactions promise greater control over reaction conditions and more timely creation of products. The small scale of microfluidics poses its own set of problems, however. At the microscale, the dominant fluid forces are viscous resistance and surface tension. The effects of viscosity and scale reduce the Reynolds number and make mixing difficult. Much work has been done to control mixing at the microscale. This problem is concerned with a different microfluidic problem: delivering reactants to the site of reaction. A common setup is to attach syringes full of reactant to a reaction chamber by narrow hydrophobic tubing. Using a stepper motor, a controlled dose of liquid may be injected into the tube. The hydrophobosity causes the dose to curve outward on the sides, becoming a "slug" of reactant with air in front and behind. The syringe at the rear is then switched for one full of air, and air pressure is used to drive the slug to the reaction site. If too much pressure is applied, the slug will arrive with a significant back pressure that will be relieved through bubbling in the reaction site. This causes the formation of a foam and is highly undesirable. We present a simple model based on Boyle’s law for the motion of a slug through a tube. We then extend this model for trains of slugs separated by air bubbles. Last, we consider the case of a flooded reaction site, where the forward air bubble must be pushed through the flooding liquid. In conclusion, we have determined the dynamics of a single slug moving towards an empty reaction chamber giving the final equilibrium position of the slug. A phase-plane analysis then determined a condition on the size of the slug needed to ensure that it comes to rest without oscillating about the equilibrium position. The effect of a flooded reaction chamber was then considered. In this case it is impossible to avoid bubbling due to the design of the device. We found that it is possible, however, to reduce the bubbling by minimising the back pressure behind the slug. Finally, the dynamics of multiple slugs with or without a flooded reaction chamber has been investigated

    Pre-Islamic religious motifs (550 BC to 651 AD) on Iranian minor art with focus on rug motifs

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    This article reviewed the influence of pre-Islamic religions such as Mithraism and Zoroastrianism on decorative elements of ancient Persian rugs. The article then evaluated the effect of the Islamic religion on Persian rugs. This was examined through extant evidence from pre–Islamic empire artefacts and publications in Persian carpet history, iconography and religious studies. Using spiritual motifs on some ancient rugs results from the important position of rugs in ancient Iranians’ lives. Believing the existence of religious motifs on Persian carpets is because the first carpet in history (Pazyryk) was attributed to the ancient Achaemenians, decorated with symbolic motifs from Mithraism and Zoroastrianism. Pazyryk shows how rug-weaving evolved during the Achaemenids, and it represented spiritual foundations through visual concepts. This article reviewed the symbolic Persian rug motifs from ancient religions through Pazyryk, with support from museum collections. With the emergence of religions, these effects are seen in all aspects of life, including the production of rug design. Contribution: The main contribution of this research was that it investigated the effects of religion on Persian art focusing on the Persian rug. The findings showed that religion had directly influenced the decorative motifs of the Persian rug among high-class families that might have cascaded into visual elements found on commoners’ rugs
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