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Information on sustainability can be used for future development planning. This study presents an approach for assessing urban sustainability. Delphi and fuzzy logic methods and the Kruskal–Wallis test were the discovery and verification techniques used. The city system comprised social, economic, and environmental subsystems. The seven orientors of existence, effectiveness, freedom of action, security, adaptability, coexistence, and psychological need were measured using different indicators. The final sustainability output was obtained by aggregation of the multiple orientors and subsystems sustainability values into a unified measure. A fuzzy sustainability index was developed to compare the importance of the sustainability orientors and subsystems. The model was applied to Mahshahr, an industrialized coastal city in Iran. The model output for the subsystems showed significant differences between the economic and environmental subsystems and the social subsystem. The final sustainability output showed that the effectiveness orientor gave the highest sustainability value. The model is dynamic and can be modified for different purposes by changing the indicators. With this model, policy-makers can evaluate existing city sustainability and predict future sustainability by varying the indicators. This can be done on local, regional, and global scales for security and adaptation strategies, mitigation plans, and sustainable development management. [ABSTRACT FROM AUTHOR]

Quantitative measurements of the excess free volume in Pd40Cu30Ni10P20 and Cu55Zr30Ti10Pd5 metallic glasses during in situ isothermal annealing at various temperatures are used to identify physical parameters of structural relaxation in metallic glasses and to discuss proposed models describing this process. The free-volume model is found to provide a simple and predictive description for structural relaxation phenomena. We show that structural relaxation kinetics follows a second-order law in a satisfactory manner. The activation energy for relaxation is found to depend on annealing temperature and the extent of structural relaxation. [ABSTRACT FROM AUTHOR]

A new bulk glassy alloy (BGA) showing macroscopic tensile plastic elongation at room temperature has been developed in the hypoeutectic Zr-Ni-Cu-Al alloy system. The hypoeutectic Zr-Ni-Cu-Al BGA shows a high Poisson's ratio, a low Young's modulus, and is highly malleable in compression. It exhibits a Poisson's ratio of 0.39, a Young's modulus of 73 GPa, and a distinct tensile plastic elongation of about 1.7% at room temperature with necking due to the operation of many shear bands. The tensile plastic deformability seems to originate from modifications of the glass structure with increasing the number of Zr-Zr atomic pairs in the hypoeutectic composition. [ABSTRACT FROM AUTHOR]

A plate of bulk metallic glass Zr55Ti5Al10Cu20Ni10, shot-peened on both faces, has been studied by synchrotron X-ray diffraction in transmission. The ellipticity in the first diffraction halo changes throughout the plate thickness. The elastic strain in the plate interior is measured and the compressive stress profile in the peened surfaces is estimated. Structural anisotropy and dilatation induced by plastic deformation preclude direct measurement of the elastic strain in the peened layers. Plastic deformation induces softening, but changes in the elastic properties remain undetermined. [ABSTRACT FROM AUTHOR]