Adaptive quantized target tracking in wireless sensor networks

This paper addresses target tracking in wireless sensor networks (WSN) where the observed system is assumed to evolve according to a probabilistic state space model. We propose to improve the use of the variational filtering (VF) by optimally quantizing the data collected by the sensors. Recently, VF has been proved to be suitable to the communication constraints of WSN. Its efficiency relies on the fact that the online update of the filtering distribution and its compression are executed simultaneously. However, this problem has been used only for binary sensor networks neglecting the transmission energy consumption in a WSN and the information relevance of sensor measurements. Our proposed method is intended to jointly estimate the target position and optimize the quantization level under fixed and variable transmitting power. At each sampling instant, the adaptive method provides not only the estimate of the target position by using the VF but gives also the optimal number of quantization bits per observation. The adaptive quantization is achieved by minimizing the predicted Cramér–Rao bound if the transmitting power is constant for all sensors, and optimizing the power scheduling under distortion constraint if this power is variable. The computation of the predicted Cramér–Rao bound is based on the target position predictive distribution provided by the VF algorithm. The proposed adaptive quantization scheme suggests that the sensors with bad channels or poor observation qualities should decrease their quantization resolutions or simply become inactive in order to save energy.     

Effect of jam processing and storage on total phenolics, antioxidant activity, and anthocyanins of different fruits

BACKGROUND: Fruits have been widely recognised as an excellent source of bioactive phenolic compounds. The purpose of this study was to evaluate the effect of jam processing of strawberry, cherry, apricot, fig and orange on the total phenolics, antioxidant activity and anthocyanins during 5 months of storage at 25 °C. RESULTS: Fresh strawberry had the highest contents of total phenolics (8503.1 mg GAE kg^?1) followed by cherry, apricot, fig and orange, respectively. Jam processing decreased the total phenolics, antioxidant activity, and anthocyanins of all fruits. Total phenolics of jam during storage decreased only in apricot, fig and orange. Fresh strawberry had the highest antioxidant activity (54.88% inhibition) followed by the other fruits. Antioxidant activity did not change in strawberry during jam storage, while there are reductions in the other fruits were observed. Fresh strawberry had the highest anthocyanins (2323.8 mg cya‐3‐glu kg^?1), followed by cherry and the other fruits, respectively. Results showed only a decrease of anthocyanins and pH in apricot and fig jams during 5 months of storage. CONCLUSION: Despite the reduction of these compounds in jam processing, it is considered a good method to maintain them during 5 months of storage. Copyright © 2011 Society of Chemical Industry     

Decolourization of dye-containing effluent using mineral coagulants produced by electrocoagulation

The colour and colour causing-compounds has always been undesirable in water for any use, be it industrial or domestic wastewaters. The discharge of such effluents causes excessive oxygen demand in the receiving water and then a treatment is required before discharge into ecosystems. This study examined the possibility to remove colour causing-compounds from effluent by chemical coagulation, in comparison with direct electrocoagulation. The inorganic coagulants (C₁, C₂ and C₃) in the form of dry powder tested, were respectively produced from electrolysis of S₁ = [NaOH (7.5 × 10⁻³ M)], S₂ = [NaCl (10⁻² M)], and S₃ = [NaOH (7.5 × 10⁻³ M) + NaCl (10⁻² M)] solutions, using sacrificial aluminium electrodes operated at an electrical potential of 12 V. Reactive textile dye (CI Reactive Red 141) was used as model of colour-causing compound prepared at a concentration of 50 mg l⁻¹. The best performances of dye removal were obtained with C₂ having a chemical structure comprised of a mixture of polymeric specie (Al₄₅O₄₅(OH)₄₅Cl) and monomeric species (AlCl(OH)₂·2H₂O and Al(OH)₃). The removal efficiency (R_A) evaluated by measuring the yields of 540 nm-absorbance removal varied from 41 to 96% through 60 min of treatment by imposing a concentration of C₂ ranging from 100 to 400 mg l⁻¹. The effectiveness of the treatment increased and the effluent became more and more transparent while increasing C₂ concentration. The comparison of chemical treatment using C₂ coagulant and direct electrocoagulation of CI Reactive Red 141 containing synthetic solution demonstrated the advantage of chemical treatment during the first few minutes of treatment. A yield of 88% of absorbance removal was recorded using C₂ coagulant (400 mg l⁻¹) over the first 10 min of treatment, compared to 60% measured using direct electrocoagulation while imposing either 10 or 15 V of electrical potential close to the value (12 V) required during C₂ production. However, at the end of the treatment (after 60 min of treatment), CI Reactive Red 141 pollutant was completely removed from solution (540 nm-absorbance removal of 100%) using direct electrochemical treatment, compared to 96.4% of absorbance removed while treating dye-containing synthetic solution by means of C₂ coagulant.     

Processing of gold ores using Guinean bauxite waste

This paper describes the treatment of gold ores via the bauxite waste mud used as a pH modifier in the cyanidation of gold. The red mud is irrefutable in modifying the pH of gold ore sludges. So any gold contained in the red mud is concentrated by gravity separation and is recovered along with gold from the gold ore. Carbon tests are carried out on cyanide leach solutions to determine the level of deactivation resulted by organics in the bauxite waste mud.     

A low-power oriented architecture for H.264 variable block size motion estimation based on a resource sharing scheme

In the Advanced Video Coding (AVC) standard, motion estimation (ME) adopts many new features to increase the coding performances such as block matching algorithm (BMA), motion vector prediction (MVP) and variable block size motion estimation (VBSME). However, VBSME is utilized in the MPEG4-AVC/H.264 standard which leads to high computational complexity and data dependency that make the hardware implementation very complex.     

Finite element analysis of countersinking process

In this work, countersinking which is the manufacturing operation used to enlarge the side of an existing hole is studied. A finite element model is built in order to get the normalized dimensions of the countersink. The obtained countersink allows to the head of screws or rivets to sit flush with the surface with the surrounding material. A case study is detailed in order to show the effect of the pertinent parameters. The procedure is summarized by the construction of a single diagram in which the coupled effects of the different parameters are shown. A fully automatic procedure can be built in the light of this analysis.     

Total Phenolics,Antioxidant Activities,and Anthocyanins of Different Grape Seed Cultivars Grown in Jordan

The total phenolics, antioxidant activities, anthocyanins, vitamine E, and tert-butylhydroxytoluene (BHT) of different cultivars of grape seed extracts (GSE) grown in Jordan were evaluated. In addition, antioxidant activities of GSE were investigated using olive oil substrate by oxidative stability instrument (OSI). Results of chemical composition showed that Baladi black and Asbani black had the highest amount of fat content 14.52 and 14.22 g /100 g seed, respectively, followed by Baladi green (13.28 g /100 g seed), Ajloni green (12.24 g/100 g seed), and Khudari green (10.92 g/100 g seed), respectively. The total phenolics and anthocyanins of GSE ranged from 4.66 to 5.12 g/100 g extracts and 0.14 to 0.68 g/100 g extracts, respectively. Antioxidant activities of GSE ranged from 66.4 to 81.40%, while vitamin E and BHT were 90.34 and 94.70%, respectively. Antioxidant activity of the extracts using OSI ranged from 3.10 to 41.13 h induction time, while vitamin E and BHT had 16.33 and 17.20 h, respectively. GSE had high amounts of antioxidants and can be used to retard lipid oxidation in a variety of food products.