Intelligent RFID Tag Detection Using Support Vector Machine

RFID Tag detection/recognition is one of the most critical issues for successful deployment of RFID systems in diverse applications. The main factors influencing tag detection by RFID reader antenna include tag position, relative position of reader, read field length, etc. In this paper, we analyze the characteristics of tag detection for a carton box object on a wooden pallet by an experimental approach based on tag signal strength, and we propose a method for predicting detection related directly to the strength of tag signal using an intelligent machine learning technique called support vector machine (SVM). The use of the proposed method is able to save time and cost by quick prediction of tag detection. Extensive experiments showed that the proposed approach can predict tag recognition for a carton box object with an accuracy at 95% for various reader heights and read field lengths. The proposed approach is effective for determining the best tag detection influencing factor conditioned on the target object with the help of detectability prediction.     

Polymeric gate dielectric interlayer of cross-linkable poly(styrene-r-methylmethacrylate) copolymer for ferroelectric PVDF-TrFE field effect transistor memory

A new polymeric gate dielectric interlayer of a cross-linkable poly(styrene-random-methylmethacrylate) copolymer is introduced with a good thermal and chemical resistance in bottom gate Ferroelectric Field Effect Transistor (FeFET) memory with pentacene active layer and ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) one. A thin uniform PVDF-TrFE film was successfully formed with well defined ferroelectric microdomains on an interlayer. Thickness of the interlayer turns out to be one of the most important factors for controlling gate leakage current which is supposed to be minimized for high ON/OFF bistability of a FeFET memory. An interlayer inserted between gate electrode and PVDF-TrFE layer significantly reduces gate leakage current, leading to source–drain OFF current of approximately 10^?11 A in particular when its thickness becomes greater than approximately 25 nm. A reliable FeFET device shows a clockwise I-V hysteresis with drain current bistablility of 10³ at ±40 V gate voltage.     

Hydrogen Production by Steam Reforming of Liquefied Natural Gas Over Mesoporous Ni-Al2O3 Composite Catalyst Prepared by a Single-step Non-ionic Surfactant-templating Method

A mesoporous Ni-Al₂O₃ composite catalyst (Ni-A-NS) was prepared by a single-step non-ionic surfactant-templating method for use in hydrogen production by steam reforming of liquefied natural gas (LNG). For comparison, a nickel catalyst supported on mesoporous alumina (Ni/A-NS) was also prepared by an impregnation method. The effect of physicochemical properties on the performance of Ni-A-NS catalyst in the steam reforming of LNG was investigated. Ni-A-NS catalyst retained superior textural properties compared to Ni/A-NS catalyst. Nickel oxide species were highly dispersed on the surface of both Ni/A-NS and Ni-A-NS catalysts through the formation of surface nickel aluminate phase. Although both Ni/A-NS and Ni-A-NS catalysts exhibited a stable catalytic performance, Ni-A-NS catalyst showed a better catalytic performance than Ni/A-NS catalyst in the steam reforming of LNG. High nickel surface area and high nickel dispersion of Ni-A-NS catalyst played an important role in enhancing the dehydrogenation reaction of hydrocarbon species and the gasification reaction of adsorbed carbon species in the steam reforming of LNG. High reducibility of Ni-A-NS catalyst was also responsible for its high catalytic performance.     

Preparation and Oxidation Catalysis of H5PMo10V2O40 Catalyst Immobilized on Nitrogen-Containing Spherical Carbon

Nitrogen-containing spherical carbon (N-SC) with a diameter of ca. 12 μm was synthesized by a hydrothermal method using melamine-formaldehyde resin as a carbon precursor. The N-SC was then modified to have a positive charge, and thus, to provide a site for the immobilization of H₅PMo₁₀V₂O₄₀ (PMo₁₀V₂) catalyst. The PMo₁₀V₂ catalyst was chemically immobilized on the surface-modified N-SC support by taking advantage of the overall negative charge of [PMo₁₀V₂O₄₀]^5?. Characterization results showed that nitrogen in the N-SC support played an important role in forming a nitrogen-derived functional group (amine group) and that PMo₁₀V₂ catalyst was chemically immobilized on the nitrogen-derived functional group of N-SC support. PMo₁₀V₂/N-SC catalyst showed a higher 2-propanol conversion than the unsupported PMo₁₀V₂ catalyst in the vapor-phase 2-propanol conversion reaction. Moreover, the PMo₁₀V₂/N-SC catalyst showed an enhanced oxidation catalytic activity (formation of acetone) and a suppressed acid catalytic activity (formation of propylene and isopropyl ether) than the unsupported PMo₁₀V₂ catalyst. The enhanced oxidation activity of PMo₁₀V₂/N-SC catalyst was due to fine dispersion of [PMo₁₀V₂O₄₀]^5? on the N-SC support formed via chemical immobilization.     

Viscoelastic and thermal behavior of woven hemp fiber reinforced poly(lactic acid) composites

This study examined the physical behavior of hemp/poly(lactic acid) (PLA) composites, particularly the thermal properties and viscoelastic behavior. Twill and plain woven hemp fabrics were used as reinforcements and hemp fabrics-reinforced PLA composites were produced using a film stacking method. The coefficient of thermal expansion of the composites decreased sharply with increasing the volume fraction of fiber. The twill structure was found to be suitable for reinforcing a PLA resin with higher impact strength and better mechanical properties than the plain woven. The viscoelastic properties of the composites including the storage modulus, loss modulus and loss tangent were also examined by dynamic mechanical analysis. In addition, morphological analysis was performed using scanning electron microscopy.     

The properties of reactive hot melt polyurethane adhesives modified with novel thermoplastic polyurethanes

A reactive hot melt adhesive (RHMA) consisting of thermoplastic polyurethane (TPU) was modified with sodium montmorillonite (Na‐MMT) intercalated with poly(ethylene glycol) (PEG), and their effects on the adhesion, rheological, and mechanical properties of the RHMA were examined. The Na‐MMT intercalated with PEG (Na‐MMT/PEG) effectively enhanced the initial bond strength development of the RHMA, although the amounts of Na‐MMT/PEG in the RHMA were less than 0.2%. The increase of the complex viscosity and pseudo‐solid like behavior observed at low shear rate indicates that there are intimate interactions between the RHMA molecules and Na‐MMT/PEG. The improved modulus and tensile strength of the cured RHMA film in the presence of Na‐MMT/PEG demonstrates that Na‐MMT/PEG effectively reinforced the RHMA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Transparent conducting films based on nanofibrous polymeric membranes and single‐walled carbon nanotubes

Transparent and electrically conducting films were fabricated using a novel and simple method in which single‐walled carbon nanotubes (SWCNTs) adsorbed onto bacterial cellulose membranes were embedded into a transparent polymer resin. The bacterial cellulose membranes consisting of numerous nanofibrils were found to play important roles in this process. The bacterial cellulose membranes impart optical transparency to the nanocomposites due to the size of the materials during the synthesis of the nanocomposite using a transparent polymer resin. The membranes play a secondary role as a template for depositing uniformly dispersed SWCNTs. This results in not only electrically conducting pathways but also prevents interference from the transmittance of optically transparent nanocomposites. Transparent conducting films with a wide range of transmittances and surface resistances could be obtained by controlling the immersion time and SWCNT concentration in the SWCNT dispersions. A transparent conducting film with a transmittance and surface resistance of 77.1% at 550 nm and 2.8 kΩ/sq, respectively, was fabricated from a 0.01 wt %. SWCNT dispersion for an immersion time of 3 h. In addition, the transparent conducting films were quite flexible and maintained their properties even after crumpling. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A numerical and experimental study on the nonlinear behavior of laminated composite structural components

Nonlinear behavior of laminated composite plates and shells is studied. In the analysis, material nonlinearity due to the matrix degradation at the initial failure is considered along with the geometrical nonlinearity in the deformation process. An effective way of accounting the damage of the material due to initial failure is incorporated into a finite element analysis of the nonlinear behavior of the structural members. Experimental study is done on the filament-wound cylinders and laminated plates. The results are compared with the ones from the numerical analysis.     

Fluorescence energy transfer immunoassay based on a long-lifetime luminescent metal-ligand complex

OBJECTIVES: Magnetization exchange experiments and force analysis were performed on porcine carotid arteries with varied phosphocreatine (PCr) levels. The aim of these experiments was to determine the creatine kinase (CK) kinetics and the role in hypoxic relaxation. METHODS: The magnetization exchange techniques used were multisite saturation transfer (MST) and conventional saturation transfer (CST). The two techniques were used because CST assumes a two-site exchange while MST allows one to assume a three-site exchange. Mechanical parameters of tension generation and relaxation were measured to determine the energetic effects on contractility of carotid strips. RESULTS: Measurements of molecular exchange between ATP and PCr found the pseudo first-order rate constant (kf) of 0.17 +/- 0.04 S-1 (PCr-->ATP) and kr = 0.12 +/- 0.03 S-1 (ATP-->PCr) in unstimulated porcine carotid artery. In the carotids, despite increased PCr and K+ stimulation, no magnetization exchange is observable with MST. This result indicates that the ATPase was less than 0.04 mumol/g/s (below the NMR resolution) while CK was 0.11 mumol/g/s. Creatine-loaded carotids showed no significant differences in force measurements: maximal force, resting tension, and the rate of hypoxia were all unchanged. CONCLUSIONS: The flux ratio (flux forward over flux reverse) was 0.94 +/- 0.13 which was considered to be indicative of CK being at equilibrium in the resting porcine carotid artery. The rate of the CK reaction is rapid enough to assume a two-site kinetic exchange not limiting energetic supply during hypoxia-induced relaxation.     

Novel model for film growth based on surface temperature developing during magnetron sputtering

New physical phenomenon consisting in development of the surface temperature T_surf, which being equal to the substrate temperature T_s at the beginning of deposition, steeply increases and becomes several times higher than T_s at the end of the process, is revealed by means of IR-camera and new calorimetric method during sputter deposition of metal films. The reason for the phenomenon is the formation of a liquid-like layer on the growth surface with extremely low (∼10⁹ times lower than for metals) thermal conductivity. Variation in the film structure along thickness correlates with the variation in T_surf. To explain these effects we developed a model according to which film grows by “gas → liquid → solid” rather than “gas → solid” mechanism which is realized provided that the film grows from energetic atoms.