Determine the location of a target has gained considerable interest over the past few years. The Received Signal Strength(RSS) measurements and Differential RSS(DRSS) measurements can be converted to distance or dista...Determine the location of a target has gained considerable interest over the past few years. The Received Signal Strength(RSS) measurements and Differential RSS(DRSS) measurements can be converted to distance or distance ratio estimates for constructing a set of linear equations. Based on these linear equations, a constrained weighted least Squares(CWLS) algorithm for target localization is derived. In addition, an iterative technique based on Newton's method is utilized to give a solution. The covariance and bias of the CWLS algorithm is derived using perturbation analysis. Simulation shows that the proposed estimator achieves better performance than existing algorithms with reasonable complexity.展开更多
With the rapid evolution of WSNs technology,it is very important to evaluate link quality quickly and accurately,so that the routing protocols can take relevant strategies in time to keep the entire network working st...With the rapid evolution of WSNs technology,it is very important to evaluate link quality quickly and accurately,so that the routing protocols can take relevant strategies in time to keep the entire network working steadily and efficiently. However,the issue of improving link quality assessment methods on physical layer is still open to research. To tackle this issue,a novel link quality assessment metric called S 3 LQA is proposed,which estimates the link quality of wireless sensor networks by CC2420 wireless radio frequency transceiver principles and free space propagation theory. The metric adopts both complete and incomplete packages to improve the evaluation performance effectively based on IEEE802. 15. 4 frame format and DSSS-O-QPSK mechanism. The experimental results show that the proposed method can improve energy cost and achieves better real-timing performance than traditional counting-based ( PRR) link quality assessment metric.展开更多
This effluent remediation research on discoloration tends to disagree with the use of commercial activated carbon as received from manufacturers. Product specification and authentication is a key task to chemists and ...This effluent remediation research on discoloration tends to disagree with the use of commercial activated carbon as received from manufacturers. Product specification and authentication is a key task to chemists and scientist. Here, Batch kinetic studies via pseudo approximations treatments was adopted to to investigate the rate of Methyl Red (MR) dye solution uptake onto carbon animalis earlier received as Granulated Activated Carbon (GAC) and later formulated as Powdered Activated Carbon (PAC). The rate of dye uptake was studied with data fitted in to the Lagergren’s pseudo first and second order kinetic models. Justification by the R2 values (0.984) for GACgreater than 0.865 for PAC, low statistical error (SSE%) range of 1.065 - 2.310 and closeness between the experimented and calculated qe values all favored the second order kinetic model. The deviation of the line from the origin further showed that intra-particle transport is not the only rate limiting step. Generally the research supported the manufacturer’s choice of particle size (as GAC and not PAC) for the chosen adsorbate.展开更多
DOUGLAS CAIRNS (Author, Editor), FRITZ-GREGOR HERRMANN (Editor), TERRY PENNER (Editor), Pursuing the Good, Ethics and Metaphysics in Plato’s Republic, Edinburgh University Press, Edinburgh, 2007.
文摘Determine the location of a target has gained considerable interest over the past few years. The Received Signal Strength(RSS) measurements and Differential RSS(DRSS) measurements can be converted to distance or distance ratio estimates for constructing a set of linear equations. Based on these linear equations, a constrained weighted least Squares(CWLS) algorithm for target localization is derived. In addition, an iterative technique based on Newton's method is utilized to give a solution. The covariance and bias of the CWLS algorithm is derived using perturbation analysis. Simulation shows that the proposed estimator achieves better performance than existing algorithms with reasonable complexity.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61262020)Aeronautical Science Foundation of China(Grant No.2010ZC56008 and 2012ZC56006)Key Technology R&D Program of Jiangxi Province(Grant No.2009BGA01000 and 20111BBE50030)
文摘With the rapid evolution of WSNs technology,it is very important to evaluate link quality quickly and accurately,so that the routing protocols can take relevant strategies in time to keep the entire network working steadily and efficiently. However,the issue of improving link quality assessment methods on physical layer is still open to research. To tackle this issue,a novel link quality assessment metric called S 3 LQA is proposed,which estimates the link quality of wireless sensor networks by CC2420 wireless radio frequency transceiver principles and free space propagation theory. The metric adopts both complete and incomplete packages to improve the evaluation performance effectively based on IEEE802. 15. 4 frame format and DSSS-O-QPSK mechanism. The experimental results show that the proposed method can improve energy cost and achieves better real-timing performance than traditional counting-based ( PRR) link quality assessment metric.
文摘This effluent remediation research on discoloration tends to disagree with the use of commercial activated carbon as received from manufacturers. Product specification and authentication is a key task to chemists and scientist. Here, Batch kinetic studies via pseudo approximations treatments was adopted to to investigate the rate of Methyl Red (MR) dye solution uptake onto carbon animalis earlier received as Granulated Activated Carbon (GAC) and later formulated as Powdered Activated Carbon (PAC). The rate of dye uptake was studied with data fitted in to the Lagergren’s pseudo first and second order kinetic models. Justification by the R2 values (0.984) for GACgreater than 0.865 for PAC, low statistical error (SSE%) range of 1.065 - 2.310 and closeness between the experimented and calculated qe values all favored the second order kinetic model. The deviation of the line from the origin further showed that intra-particle transport is not the only rate limiting step. Generally the research supported the manufacturer’s choice of particle size (as GAC and not PAC) for the chosen adsorbate.
文摘DOUGLAS CAIRNS (Author, Editor), FRITZ-GREGOR HERRMANN (Editor), TERRY PENNER (Editor), Pursuing the Good, Ethics and Metaphysics in Plato’s Republic, Edinburgh University Press, Edinburgh, 2007.
