Local Prediction of Chaotic Time Series Based on Support Vector Machine

Based on phase space delay-coordinate reconstruction of a chaotic dynamics system, we propose a local prediction of chaotic time series using a support vector machine （SVM） to overcome the shortcomings of traditional local prediction methods. The simulation results show that the performance of this proposed predictor for making onestep and multi-step prediction is superior to that of the traditional local linear prediction method and global SVM method. In addition, it is significant that its prediction performance is insensitive to the selection of embedding dimension and the number of nearest neighbours, so the satisfying results can be achieved even if we do not know the optimal embedding dimension and how to select the number of nearest neighbours.     

Profile Analysis of Ferrite–Garnet Films by Glow-Discharge Optical Emission Spectroscopy

Technical Physics - The results of experiments on the application of the method of glow discharge optical emission spectroscopy for the profile analysis of vacuum-deposited single- and double-layer...     

Quantitative Analysis of Protein–Protein Interactions by Native Page/Fluorimaging

We have developed a new quantitative native PAGE mobility shift assay, which allows for the measurement of binding affinities for interacting protein pairs, one of which is fluorescently labelled. We have used it to examine recognition of the Simian virus 40 (SV40) large tumour T-antigen (T-ag) nuclear localisation sequence (NLS) by members of the importin (Imp) superfamily of nuclear transport proteins. We demonstrate that the T-ag NLS binds to the Imp α/β heterodimer in NLS-dependent manner, determining that it binds with eight-fold higher affinity (340 nM), when compared to Imp α alone, consistent with autoinhibition of Imp αwhen not complexed with Imp β. The mobility shift assay is able to detect nM binding affinities, making it a sensitive and useful tool to analyse protein–protein interactions in solution.     

Fourier‐Transform Near‐Infrared Spectroscopy as a Tool for Olive Fruit Classification and Quantitative Analysis

Abstract

The potential of diffuse reflectance near‐infrared spectroscopy combined with pattern recognition to discriminate between olives (Olea europaea L.) of different qualities has been tested. The sample set was formed of sound olive fruits and those showing the most common alterations of olives, which lead to decreased oil quality, namely freeze damages, harvest after falling on the ground, fermentation due to prolonged storage time, and olive tree diseases. Near‐infrared (NIR) spectra were recorded between 9900 and 4100 cm^?1. Preliminary studies of the data set structure were performed using hierarchical cluster analysis and principal component analysis. Discriminant analysis provided prediction abilities of 100% for sound, 79% for frostbite, 96% for ground, and 92% for fermented olives using a leave‐a‐fourth‐out cross‐validation procedure. Quantification of oil and water content in the olives was also approached by using partial least squares (PLS) regression. Results, in terms of predictive ability using a leave‐one‐out cross‐validation, were compared for calibration using the whole sample set and calibrations for the sound and damaged samples separately. Relative errors of prediction using all samples were 7.2% and 3.4% for oil content and humidity, respectively. Using only sound samples, relative errors of prediction of 3.8% and 2.8% for oil and water content, respectively, were obtained. Thus, better accuracy could be achieved when classification of the olive samples prior to quantitative analysis was performed. These results demonstrate the utility of NIR spectroscopy to differentiate olives of different qualities. Using NIR, a fast selection of sound olives in a quality‐orientated production facility becomes feasible.     

Analysis of Experimental Results by the Havriliak–Negami Model in Dielectric Spectroscopy

The problem of identifying experimental results on studying frequency dependences of the real and imaginary parts of dielectric permittivity concerning the correspondence to one of accepted frequency dispersion models: Debye, Cole–Cole, Davidson–Cole, and Havriliak–Negami models is considered. Based on expressions for components of complex dielectric permittivity with the use of mathematical analysis, a sequence of steps for the determination of the following characteristic parameters of the generalized Havriliak–Negami model is developed: static ε _S and high-frequency ε_∞ dielectric permittivity, frequency dispersion indices α and β, and relaxation time τ. As an example, the parameters ε _S , ε_∞, α, β, and τ are calculated for a sample of a frozen disperse medium based on fine-grained quartz powder at a humidity of 13% in a temperature range from –140 to 0°C.     

Analysis of Glasses Coated with Zn–Cr–Sn–O Thin Films by Picosecond Laser-Induced Breakdown Spectroscopy and Transmission Spectroscopy

Journal of Applied Spectroscopy - Glasses coated with different thin fi lm layers exhibit different optical properties. Thus, ZnO thin films with Sn and Cr admixture (ZCTO) were deposited on the...     

A Method for Quantitative Analysis of Chemical Mixtures with THz Time Domain Spectroscopy

A method for analysing chemical mixtures quantitatively with terahertz time domain spectroscopy is proposed. The experimental results demonstrate the feasibility of this technique. Transmission coefficient of THz wave at the sample surface is taken into account to improve the analytic precision, lsomer mixtures are chosen as the experimental samples. Compared to similar techniques, the analytic precision could be improved evidently in this method.     

Intumescent Flame Retardancy and Thermal Degradation of Epoxy Resin Filled with Ammonium Polyphosphate Using Thermogravimetric Analysis–Fourier Transform Infrared Spectroscopy and Thermogravimetric Analysis–Mass Spectrometry

The flammability of epoxy resin (EP) and its composite with ammonium polyphosphate (EPAPP) was investigated with limiting oxygen index (LOI), UL 94, and cone calorimeter tests. A systematic and comparative evaluation of the thermal degradation of EP and EPAPP has been investigated using thermogravimetry coupled with Fourier transform infrared spectroscopy (TG–FTIR) and thermogravimetry coupled with mass spectrometry (TG–MS). The results showed that the flame retardant of ammonium polyphosphate (APP) can constitute an intumescent flame retardant (IFR) system with EP, and APP can effectively improve the LOI of EP; with 6 wt% addition level of APP, EPAPP can pass UL 94 V 0 test. The cone calorimeter test results showed that the flame retardancy and smoke suppression of EP were significantly improved by APP, and toxic gas products such as carbon monoxide and carbon dioxide obviously decreased. Thermogravimetry–Fourier transform infrared spectroscopy and TG–MS results showed that the degradation process of EP produces large amounts of gas products and mainly containing of water, carbon dioxide, methane, benzene and its derivatives, as well as phenol and its derivatives. Compared to EP, the kinds of decomposition products of EPAPP sample were not changed significantly, except that more ammonia gas was generated. For the EPAPP sample, the products of water, benzene, and phenol increased, whereas the carbon dioxide and the flammable hydrocarbon fragments C_xH_y decreased significantly during the decomposition.     

Analysis of X-Ray Photoelectron Spectroscopy of Polymethyl Methacrylate Etched by a KrF Excimer Laser

The C ls and 0 ls electrons in polymethyl methacrylate etched by different incident laser intensities are analysed by x-ray photoelectron spectroscopy. The results show that when the incident laser fluence increases gradually,the percentage of carbon atoms in C-C bonds decreases while the one in carbonyl group (C=O) and alkoxy group (C-O) increases, and the percentage of oxygen atoms in C=O bonds increases while the one in C-O bonds decreases. Based on the analysis of the chemical structure, the energy level transition, energy diversion, and dissociation of bonds are theoretically examined, which is consistent with the experimental results.     

Raman Spectroscopy–Based Multivariate Statistical Analysis Reveals the Molecular Mechanism of K562 Cell Apoptosis Induced by Adriamycin

Based on the combination of Raman spectroscopy with principal component analysis and hierarchical cluster analysis, the molecular mechanism of K562 cell apoptosis induced by Adriamycin in physiological conditions is presented. The obtained results reveal that DNA of K562 cells treated with Adriamycin is lowered greatly, indicating that the damage of the DNA of K562 cells is indeed the main molecular mechanism of K562 cell apoptosis induced by Adriamycin. Specially, by combining principal component analysis and hierarchical cluster analysis, the statistical difference between Raman spectra of different cell types can be revealed effectively. Importantly, this kind of Raman spectroscopy–based multivariate statistical analysis will supply a useful tool for the molecular mechanism detection of cell behavior in physiological conditions.     

Inverse Scattering Transform of the Coupled Sasa–Satsuma Equation by Riemann–Hilbert Approach

The inverse scattering transform of a coupled Sasa–Satsuma equation is studied via Riemann–Hilbert approach. Firstly, the spectral analysis is performed for the coupled Sasa–Satsuma equation, from which a Riemann–Hilbert problem is formulated. Then the Riemann–Hilbert problem corresponding to the reflection-less case is solved.As applications, multi-soliton solutions are obtained for the coupled Sasa–Satsuma equation. Moreover, some figures are given to describe the soliton behaviors, including breather types, single-hump solitons, double-hump solitons, and two-bell solitons.     

Target oriented dimensionality reduction of hyperspectral data by Kernel Fukunaga–Koontz Transform

Principal component analysis (PCA) is a popular technique in remote sensing for dimensionality reduction. While PCA is suitable for data compression, it is not necessarily an optimal technique for feature extraction, particularly when the features are exploited in supervised learning applications (Cheriyadat and Bruce, 2003) [1]. Preserving features belonging to the target is very crucial to the performance of target detection/recognition techniques. Fukunaga–Koontz Transform (FKT) based supervised band reduction technique can be used to provide this requirement. FKT achieves feature selection by transforming into a new space in where feature classes have complimentary eigenvectors. Analysis of these eigenvectors under two classes, target and background clutter, can be utilized for target oriented band reduction since each basis functions best represent target class while carrying least information of the background class. By selecting few eigenvectors which are the most relevant to the target class, dimension of hyperspectral data can be reduced and thus, it presents significant advantages for near real time target detection applications. The nonlinear properties of the data can be extracted by kernel approach which provides better target features. Thus, we propose constructing kernel FKT (KFKT) to present target oriented band reduction. The performance of the proposed KFKT based target oriented dimensionality reduction algorithm has been tested employing two real-world hyperspectral data and results have been reported consequently.     

Analysis of hyperfine structure of Rare‐Earth Ions in Single Crystals by Electron Paramagnetic Resonance Spectroscopy

Electron paramagnetic spectroscopy of rare‐earth ions in single crystals is an interesting tool to analyze the hyperfine structure of the ground state of the rare‐earth. This can be useful for coherent spectroscopy and quantum information applications where the hyperfine structure of the electronic levels is used. Moreover, in some cases, the electron paramagnetic resonance hyperfine structure of interacting rare‐earth ions allows us to retrieve the isotropic exchange interaction between the two interacting ions. We illustrate these points with the hyperfine structure of Yb³⁺ ions in vanadate crystals, the hyperfine structure of Er³⁺ ions in Y₂SiO₅, and the hyperfine structure of Yb³⁺ pairs in CsCdBr₃.     

Analysis of Electrical Properties of Post-Annealed Polycrystalline CaCu3Ti4O12 Films by Impedance Spectroscopy

Impedance spectroscopy is performed to establish the electrical property and microstructure relations of the asdeposited and post-annealed polycrystalline CaCu3Ti4O12 （CCTO） films. Our results show that the resistance and capacitance of the grains and grain boundaries could be tuned by changing the annealing atmosphere and temperature. The simple resistor-capacitor equivalent circuit and the modified constant phase element （CPE） circuit are used to describe the impedance spectroscopy, and excellent agreement between the calculated and measured curves is obtained in the CPE circuit. Based on the experimental results, it is suggested that the origin of the semiconductivity of the grains in CCTO polycrystalline films originates from their oxygen-loss, while the grain boundaries are close to oxygen- stoichiometry.     

Monitoring the pH-Dependent Oximation of Methyl Ethyl Ketone and Benzaldehyde by in situ Fourier Transform IR Spectroscopy in a Heterogeneous Liquid–Liquid Two-Phase System

In situ Fourier transform IR spectroscopy was a useful tool in monitoring the pH-dependent and two-step oximation of methyl ethyl ketone and benzaldehyde in a liquid–liquid two-phase system, one phase of which was water. Carrying out the oximations at pH 8, the oximation was complete within 45 min and the corresponding carbonyl compound–hydroxylamine adduct (2) could be detected as an intermediate, but at pH 10, the corresponding oxime (3) was formed faster, practically without the appearance of the intermediate. At pH ～ 2.5 using methyl ethyl ketone, the protonated form of the corresponding oxime (3'a) developed gradually without the transient appearance of the intermediate (2). pH dependence of the 3a → 3'a and 3'a → 3a interconversions were studied in separate experiments.     

Annealing Behaviour of Helium Bubbles in Titanium Films by Thermal Desorption Spectroscopy and Positron Beam Analysis

Helium-containing Ti Glms are prepared using magnetron sputtering in the helium-argon atmosphere. Isochronal annealing at different temperatures for an hour is employed to reveal the behaviour of helium bubble growth. Ion beam analysis is used to measure the retained helium content. Helium can release largely when annealing above 970K. A thermal helium desorption spectroscopy system is constructed for assessment of the evolution of helium bubbles in the annealed samples by linear heating （OAK/s） from room temperature to 1500K. Also, Doppler broadening measurements of positron annihilation radiation spectrum are performed by using changeable energy positron beam. Bubble coarsening evolves gradually below 680K, migration and coalescence of small bubbles dominates in the range of 68-970 K, and the Ostwald ripening mechanism enlarges the bubbles with a massive release above 970K.