CRAMStrack: Enhanced Nonlinear RSSI Tracking by Using Circular Multi-Sectors

Indoor localization using a Received Signal Strength Indicator (namely, RSSI localization) has been considered a poor measurement for target tracking. The main cause of this inaccurate measurement is that RSSI’s behaviors heavily depend on environmental factors. That is, one significant challenge to localization using RSSI is that the strength of a signal varies with the environment confounding wireless communications power and signal control. In this paper, we propose Circular RSSI And Multi-Sector tracking (CRAMStrack), a novel approach to reducing the uncertainty of RSSI localization by modifying the relationship of RSSI-to-Distance (RtD), based on the sectors of a circle and the position of the tracked target. Traditional RSSI tracking uses one uniform RtD relationship to locate a target whereas CRAMStrack utilizes multiple RtD responses for each wireless sensor. The paper examines CRAMStrack’s tracking ability in a Euclidean space with estimation techniques. Real-world experiments demonstrate CRAMStrack in a testbed environment to locate targets in both stationary, linear, and non-linear movement patterns with single and group-based formations. The track accuracy was about 1.46m for moving targets, while CRAMStrack had a 40% reduction in Root Mean Square Error (RMSE) over Uni-RtD using neighboring sensor information.

     

Alkyl ether and enol ether analogs of (Z)-5-decenyl acetate,a pheromone component of the turnip moth,Agrotis segetum: probing a proposed bioactive conformation for chain-elongated analogs

In order to test a previous conclusion that chain-elongated analogs of (Z)-5-decenyl acetate(1), a pheromone component of the turnip moth,Agrotis segetum, adopt a loop conformation of the terminal alkyl chain in the bioactive conformation, a series of alkyl ether and enol ether analogs of1 and (Z)-5-dodecenyl acetate(2) have been synthesized and tested using singlecell electrophysiology. In these analogs a methylene group in positions 7 and 9 of1 and in positions 7 and 11 in2 have been replaced by an oxygen atom in order to energetically facilitate the formation of a loop conformation in the chain-elongated analogs. The electrophysiological results in combination with molecular mechanics (MM2 and MM3) calculated conformational energies show that the activity decreases of the chain-elongated ether analogs are significantly smaller than that for2 and that these activity decreases parallel the conformational energies for a loop formation of the terminal chains in the analogs. The results support our previous conclusion that the terminal chain of chain-elongated analogs of1 adopts a loop conformation in their bioactive conformations.     

Enantiomers of methyl substituted analogs of (Z)-5-decenyl acetate as probes for the chirality and complementarity of its receptor inAgrotis segetum 1: Synthesis and structure-activity relationships

The enantiomers of analogs of (Z)-5-decenyl acetate, a pheromone component ofAgrotis segetum, substituted by a methyl group in the 2, 3, 4, 7, and 8 positions and dimethyl substituted in the 4,7 positions, have been synthesized and studied by an electrophysiological single-cell technique and by molecular mechanics calculations. The results demonstrate that the electrophysiological activity as well as the ability of the (Z)-5-decenyl acetate receptor to differentiate between enantiomers depends on the position of the methyl substituent. For analogs methyl substituted in the 2, 4, or 8 position, no differences in the activities of the enantiomers could be observed. In contrast, the enantiomers of the 3- and 7-methyl analogs display a significant difference in the activities, theR-enantiomers being more active than theS-enantiomers. From an analysis of the structure-activity results of the enantiomers of the 4,7-dimethyl-substituted analogs, the chiral sense of the alkylchain of the natural pheromone component on binding to its receptor could be deduced.Schiff., Lepidoptera: Noctuidae.     

The effects of air content on permeability of lightweight concrete

Air entraining agent is used to control the floatation of lightweight aggregate (LWA) in lightweight aggregate concrete (LWAC), therefore reducing the segregation of LWAC. At the same time, using an air entraining agent will affect the water sorption of the concrete. In this paper, two lightweight concrete mixes of density 1000 kg/m³ and air content of 13.5% and 31.9% were compared and the effects of entrained air on the strength, surface sorptivity, and chloride permeability of LWAC are presented. Results show that the use of porous LWA would not lower the permeability resistance of concrete. Entrained air had little effect on sorptivity but a major effect on chloride permeability. The weaker pores' network in the cement paste is the basic cause for the high chloride permeability of concrete than the use of porous LWA. Although chloride permeability of low density LWAC concrete decreased with age of concrete, it was found that the concrete was not dense enough to stop the chloride ion to penetrate through the concrete before the concrete mature at 90 days.     

Forest‐based resources as fillers in biobased polyurethane foams

Six fillers from forestry wastes (wood, bark, cones and needles from young pine trees, kraft lignin, and recycled paper sludge from industry wastes) were incorporated into polyurethane (PU)‐based foams prepared via free‐rise pouring method. Variable filler contents (1, 5, and 10 wt %) and NCO/OH ratios (0.6, 0.9, and 1.2) were investigated. A simple mixture (1:3) of castor oil and crude glycerin (byproduct from biodiesel production) was used as biobased polyol. The foam composites were investigated through spectroscopy, morphological, mechanical, and hygroscopic analyses. The addition of fillers decreased water uptake and yielded rigid PU systems with more homogenous cell structure. The 1% and 5% reinforcement wood were the most effective among the studied compositions, with better mechanical and hygroscopic performance, probably due the higher compatibility of the wood with the PU system, which promote urethanic bonds between filler and isocyanate, as indicated by wet chemical results and micrographs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45684.     

Strength analysis of bamboo by microscopic investigation of bamboo fibre

This paper presents the mechanical properties of two bamboo species, namely Mao Zhu and Kao Zhu, which are commonly used for scaffolding in Southern China. Variations of the compressive strength against the physical properties of bamboo along the culms for both bamboo species were compared. A correlation of the average number of vascular bundle to the compressive strength of both bamboo species was developed. Findings indicate that the compressive strength of both Kao Zhu and Mao Zhu ranged between 45 and 65 N/mm² and the compressive strength of top section bamboo was higher than the bottom section. The fibre area of the top section bamboo was also found to be greater than bottom section bamboo from microstructure count of the sclerenchyma fibre within the vascular bundle of bamboo section. The microscopic examination of sclerenchyma fibre of bamboo section can be an alternative measure of the strength of bamboo for construction use.     

Assessment of two enzyme-linked immunosorbent assay tests marketed for detection of ruminant proteins in finished feed

The performance characteristics of two enzyme-linked immunosorbent assay (ELISA) test kits, ELISA Technologies' MELISA-Tek test and Tepnel BioSystems' BioKit for (Cooked) Species Identification test, designed to detect ruminant proteins in animal feed, were evaluated. The test kits were evaluated by using acceptance criteria developed by the U.S. Food and Drug Administration's Center for Veterinary Medicine Office of Research for evaluating selectivity, sensitivity, ruggedness, and specificity. The acceptance criteria for determining success used a statistical approach requiring a 90% probability of achieving the correct response within a 95% confidence interval. In practice, this measure requires the test to achieve the correct response 58 times for every 60 samples evaluated, or a 96.7% accuracy rate. A minimum detection level of 0.1% bovine meat and bone meal (BMBM) was required, consistent with the sensitivity of the analytical methods presently used by the U.S. Food and Drug Administration. Selectivity was assessed by testing 60 dairy feed samples that contained no added animal proteins; sensitivity was determined by evaluating 60 samples (per level of fortification) of this same feed that contained 0.025, 0.05, 0.1, 0.25, 0.5, 1, or 2% BMBM. The MELISA-Tek test passed the acceptance set-point criteria for selectivity assessment but failed the sensitivity assessment at all levels except at the 2% level. The MELISA-Tek test came close to passing at the 1% level, detecting true-positive findings at a rate of 93%, but failed at lower levels, in spite of the label claim of 0.5% sensitivity. The BioKit for (Cooked) Species Identification test detected only 2 of 17 samples fortified at the 2% BMBM level and failed to detect any other BMBM-fortified samples. The results of this evaluation indicate that neither test is adequate for regulatory use.     

A Fast Heuristic Global Learning Algorithm for Multilayer Neural Networks

This paper presents a novel Heuristic Global Learning (HER-GBL) algorithm for multilayer neural networks. The algorithm is based upon the least squares method to maintain the fast convergence speed, and the penalized optimization to solve the problem of local minima. The penalty term, defined as a Gaussian-type function of the weight, is to provide an uphill force to escape from local minima. As a result, the training performance is dramatically improved. The proposed HER-GBL algorithm yields excellent results in terms of convergence speed, avoidance of local minima and quality of solution.     

Apparent chemical composition of nine commercial or semi-commercial whey protein concentrates, isolates and fractions

Summary Analytical results are given for whey powders prepared on a commercial or semi-commercial scale by three companies. Altogether, five preparations enriched in β-lactoglobulin, four whey protein isolates and a fraction enriched in α-lactalbumin were analyzed for protein composition, including %β-lactoglobulin, α-lactalbumin, bovine serum albumin, casein (glyco) macropeptide and the main triglycerides. Protein composition was determined by high pressure gel permeation and reversed phase liquid chromatography and by capillary zone electrophoresis. The extent of modification of the native β-lactoglobulin structure was also measured through the degree of lactosylation and the fraction of accessible free sulphydryl groups. One significant finding was that the calculated recovery of protein following quantitation of the chromatogram or electropherogram was seldom above 90% and occasionally below 60% of that loaded onto the column or capillary, raising doubts as to the reliability of the analytical results. Extrapolation by linear regression to 100% recovery allowed estimates to be made of the true β-lactoglobulin composition of the samples. The nine samples could be placed into three distinct groups with estimated true β-lactoglobulin weight % of 70.9 ± 1.1, 62.0 ± 3.4 and 39.5 ± 4.9. Physico-chemical properties of the group of samples are reported elsewhere (Holt et al ., 1999).     

Plasma-assisted molecular beam epitaxy of ZnO on in-situ grown GaN/4H-SiC buffer layers

Plasma-assisted molecular beam epitaxy (MBE) was used to grow ZnO(0001) layers on GaN(0001)/4H-SiC buffer layers deposited in the same growth chamber equipped with both N- and O-plasma sources. The GaN buffer layers were grown immediately before initiating the growth of ZnO. Using a substrate temperature of 440°C–445°C and an O₂ flow rate of 2.0–2.5 sccm, we obtained ZnO layers with smooth surfaces having a root-mean-square roughness of 0.3 nm and a peak-to-valley distance of 3 nm shown by AFM. The FWHM for X-ray rocking curves recorded across the ZnO(0002) and ZnO(101ˉ5) reflections were 200 and 950 arcsec, respectively. These values showed that the mosaicity (tilt and twist) of the ZnO film was comparable to corresponding values of the underlying GaN buffer. It was found that a substrate temperature >450°C and a high Zn-flux always resulted in a rough ZnO surface morphology. Reciprocal space maps showed that the in-plane relaxation of the GaN and ZnO layers was 82.3% and 73.0%, respectively and the relaxation occurred abruptly during the growth. Room-temperature Hall-effect measurements showed that the layers were intrinsically n-type with an electron concentration of 10¹⁹ cm^–3 and a Hall mobility of 50 cm²·V^–1·s^–1.