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The parent NaX and KL samples were prepared by hydrothermal crystallization and their corresponding K- and Na-exchanged forms were obtained by post-synthesis modification by conventional ion-exchange technique. NaX, NaKX, KL and NaKL samples were characterized by powder XRD, IR, low temperature nitrogen adsorption and chemical analyses. Their sorption uptake behaviour has been investigated by gravimetric method. The kinetics of sorption using different sorbate probe molecules such as water, benzene and n-hexane was measured at 298 K, at P/P0= 0.5 for 90 minutes. All the results obtained were discussed in terms of the compositional and structural variations of the adsorbents. Lack of high dimensionality of the pore system, less openness in structure, low average framework oxygen charge and less number of accessible nonframework cations are some of the prominent factors which has resulted in reduced hydro- and organo-philicity in LTL type zeolites as compared to X-type. The size and concentration of the accessible nonframework cations were also found to influence the sorptive properties of these aluminous large pore zeolites. Among all the probe molecules, n-hexane was found to be as a promising probe for differentiating the structural peculiarities especially dimensionality of the pore system.

Sorption techniques have been employed for monitoring progress in the hydrothermal crystallization of synthetic MFI-type gallosilicate from a (TEBA)2O–Na2O–Ga2O3–SiO2–H2O system at 453 K. The samples obtained at different stages in the crystallization process were also examined by other conventional techniques such as XRD, IR, TG/DTA, N2adsorption and chemical analysis. The influence of the crystallinity on the BET surface area and on the micropore void volume was examined using low-temperature nitrogen adsorption. The sorption uptake behaviour was studied on samples of varying crystallinity using different sorbate probe molecules such as water, n-hexane and cyclohexane. The amount of sorbate uptake was found to be sensitive to the crystallinity of the sample and the characteristics of the probe molecules employed. The crystallinity as estimated by XRD methods has been compared with that obtained by sorption uptake using different probe molecules. In comparison to other sorbates, the uptake of n-hexane was found to yield a more realistic estimation of the degree of crystallization of the intermediate phases. The crystallinity evaluated from the uptake of n-hexane was found to be in close agreement with that estimated by XRD methods as compared to the crystallinity evaluated using other conventional techniques. The correlation between the crystallinity obtained by sorption measurements and by other methods such as XRD, IR, TG/DTA and N2adsorption was discussed and compared.

Sorption techniques have been employed to estimate the amorphous contribution obtained during the progressive hydrothermal crystallization of the LTL phase from the K2O–Al2O3–SiO2–H2O system at 423 K. The curve showing the progressive depletion of the amorphous content as a function of the crystallization time exhibited an inverted sigmoidal-type shape indicative of distinct induction and crystallization stages. Samples with varying amorphous contributions were characterized by sorption uptake, XRD and chemical composition. The sorption uptake changes observed were found to be helpful in estimating the progress of the crystallization process. The influence of the amorphous contribution on the BET and Langmuir surface areas, and on the micropore void volume was examined using low-temperature nitrogen sorption methods. Estimation of the amorphous contribution by XRD has been compared with that estimated via sorption uptake using different probe molecules such as water, n-hexane, cyclohexane and benzene. The sorption uptake was found to be sensitive to the extent of amorphous content in the sample and to the characteristics of the probe sorbates. The sample with a 100% amorphous contribution as estimated by XRD methods exhibited lower values for this contribution when estimated by sorption techniques. The estimation of the amorphous contribution using benzene sorption data was found to be in excellent agreement with the amorphous contribution as estimated by XRD methods. A lower agreement was exhibited by the other sorbate probes studied.

An approach to the problem of supervised texture segmentation using nonlinear support vector machines (SVMs) is presented. For each texture class a nonlinear SVM is constructed which separates that class from the other classes. The segmentation then works by applying all the SVMs to an input image and arbitrating between the SVM outputs. Experimental results show the effectiveness of the proposed method.

The authors present a method for locating car license plates using neural networks. Neural networks are used as filters for analysing small windows of an image and deciding whether each window contains a license plate. A post-processor combines these filtered images and gives the final location of the license plates. The method offers robustness when dealing with noisy images. Tests with car images travelling on the road and at the entrance of a car park showed extraction rates of 99 and 97.5%, respectively. These results suggest that the proposed method works well with real-world situations.

Cognizance of common reasons for failure in primary and revision TKA, together with their time course, facilitates prevention. However, there have been few reports specifically comparing modes of failure for primary vs. revision TKA using a single prosthesis. The goal of the study was to compare the survival rates, modes of failure, and time periods associated with each mode of failure, of primary vs. revision TKA.

Kernel principal component analysis (PCA) is presented as a mechanism for extracting textural information. Using the polynomial kernel, higher order correlations of input pixels can be easily used as features for classification. As a result, supervised texture classification can be performed using a neural network.