Image scale determination for optimal texture classification using coordinated clusters representation

The efficiency of texture image classification is certainly influenced by image scale when a feature space or a classification method is not scale invariant. An alternative approach to the scale-invariant techniques is proposed that first estimates an effective image scale and then uses it to adjust texture features to get the best possible texture image recognition and classification. We use the correlation distance between pixels as a measure of the scale of texture images. We study the performance of classification of texture images in the coordinated cluster representation (CCR) versus an image scale and the size of the scanning window used for the coordinated cluster transform. Given the number of classes to be classified in, we find that an optimal (up to 100%) classification efficiency in the CCR feature space is obtained by changing an image scale and/or the size of the scanning window in the coordinated cluster transform.     

The Relational Aspect to High Reliability Organization

The literature on ‘high reliability organizations’ demonstrates how central reliability is to organizing in certain highly demanding settings. In more mundane settings, however, where there may not be a dominant type of catastrophic failure, the meaning attributed to reliability is less likely to be unambiguous and consensual. It is more likely to be explicitly relational: a quality of the relationship between an entity that is being relied on and an entity that is relying on it. This draws attention to the importance of the relying process in contributing to how a system performs and whether it meets expectations. A field study was carried out in a highway construction and maintenance organization to analyse the various understandings of reliability that organizational members had in different contexts. It found that there were multiple understandings – involving a capacity not only to achieve particular outcomes but also comply with norms, fit behaviour to situations, and communicate about what could and could not be achieved. It also found that reliability problems were not solved in some simple sense. Instead they were transformed into other reliability problems that then had to be managed by further effort or by other organizations. We suggest that recognizing the multiple meanings of reliability, the importance of relying, and the way in which reliability problems are transformed from one form to another all have important practical implications.     

Modification of polyvinylchloride in solution or suspension by nucleophilic substitution

Nucleophilic displacement of chlorine from polyvinylchloride (PVC) suspended either in water or in solution can be achieved using a nucleophile such as a sodium thiolate (R? S^?, Na⁺). The nucleophilicity of the salt increases if an ether linkage exists in a β position to the thiol group [R? O? (CH₂)₂? S^?, Na⁺]. Addition of a solvent such as cyclohexanone (which is a good solvent for PVC) to the slurry increases substantially the degree of substitution. Elemental analysis shows that every chlorine displaced from the polymer is replaced by a thiolate group; thus almost no dehydrochlorination occurs. It is possible to obtain by this method a grafted polymer in which 33% of the chlorine atoms are replaced by the β-ether thiolate group. The resulting polymer behaves like an internally plasticized PVC. The higher the degree of substitution of chlorine, the greater the flexibility of the grafted polymer is. Other compounds, such as lauryl thiolate and diethyl dithiocarbamate, also were used as nucleophiles, the latter one resulting in a brittle crosslinked polymer whenever sulfur was above 2%. Grafting of polytetrahydrofuran from PVC also was achieved using tetrahydrofuran as solvent and silver-perchlorate as catalyst. The resulting flexible grafted polymer is believed to consist of longer chains of polytetrahydrofuran grafted from few displaced chlorine atoms along the PVC chain.     

Functional polysiloxanes

Summary Carboxyester- and carboxyamido-terminated polydimethylsiloxanes were obtained through the reaction of cyclic anhydrides (succinic, maleic and phthalic anhydride) with hydroxypropyl- and aminoalkyl-terminated polydimethylsiloxanes, respectively. The reactivity of the starting compounds and the influence of the reaction conditions on the characteristics of the final products are discussed.Part 1: Eur. Polym. J., in press     

Heteroclinic Connections in the Kuramoto-Sivashinsky Equation: a Computer Assisted Proof

On the example of a finite dimensional approximation of the Kuramoto-Sivashinsky equation we show how topological methods may be successfully used in computer assisted proofs of the existence of heteroclinic connections in ordinary differential equations.     

The Cycles and Spirals of Justice in water-allocation decision making

Managing for social and environmental justice in water allocation is a necessary yet challenging goal. Often, what can appear as a just or equitable outcome for a specific location or group of stakeholders can also result in injustices at other locations or for other stakeholders. This paper describes a conceptual framework, The Cycles and Spirals of Justice, that helps make sense of the relationship between justice and injustice in the context of water-allocation decision making by explicitly utilizing a landscape-ecology understanding of scale and levels. The framework is illustrated using a case study from the Murray-Darling Basin in Australia and describes how justice and injustice are part of a cycling continuum of “justice for whom” and how this plays out in a multi-level system where the problem of scale can surface.     

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Influence of technological conditions on electronic transitions in chemical vapor deposited poly(azomethine) thin films

Thin films of poly(1,4-phenylenemethilidynenitrilo-1,4-phenylenenitrilomethilidyne) (PPI) have been prepared by chemical vapor deposition in the horizontal geometry using gaseous argon as a transport agent. PPI thin films have been grown by polycondensation of para-phenylene diamine (PPDA) and terephtal aldehyde (TPA). Fourier Transform Infrared spectra confirm formation of PPI layers without end groups. The strongest absorption band with discernible vibronic progression has been found to be due to superposition of 2.64, 2.82 and 3.03 eV bands corresponding to interband transitions connecting electronic ground state and vibrational levels of electronic excited state. A feature seen at about 2.6 eV in the spectra of PPI films prepared at higher temperatures of PPDA and TPA sources are attributed to excitons connected with the π-π? gap. Shoulder at 3.31 eV is attributed to interband transitions between delocalized states, while a peak at 4.2 eV is attributed to excitons formed by localized holes and delocalized electrons and vice versa and interband transitions connecting delocalized and localized bands, with the binding energy of about 0.8 eV. Thin films prepared at low temperatures of monomers consist of randomly distributed PPI chains weakly bound together.