introduction: occupational exposure to excessive noise is commonly encountered in a large number of industries in iran. this study evaluated the hearing threshold and hearing loss in meybod tile factory workers. methods: this cross-sectional study included 371 tile factoryworkers during summer and autumn of 2005. current noise exposure was estimated using sound level meter .a specially formatte...

nowadays, by increasing the emphasis on the environmental protection by organizational stakeholders, including government, customers, employees, competitors and communities, environmental management is becoming more important for corporations. integrating environmental management techniques along the supply chain is an appropriate method for enhancing the environmental performance of an industr...

Tile responses of artificial neural networks to experimental and model generated inputs are compared for detection of damage in twisted fan blades using electronic holography. Tile training set inputs, for this work, are experimentally generated cllaracteristic pattenls of tile vibrating blades. Tile outputs are damage flag indicators or second derivatives of tile sensitivity vector projected d...

Buyer cooperatives, buyer alliances, and horizontal mergers are often perceived as attempts to increase buyer power. While prior theoretical and empirical work has emphasized that buyer size can increase buyer surplus, I show that even a small group of buyers with heterogeneous preferences can increase price competition among rival sellers by forming a buyer group and committing to buy exclusiv...

We extend the study of Akiyama’s tile-makers: surfaces whose developments all tile the plane. First, we prove that the developments of Akiyama’s tile-makers are the prototiles that tile the plane isohedrally with rotation and without reflection. Second, we give a simple characterization of all closed (boundaryless) tile-makers and give three new tile-makers not known to Akiyama. Finally, we pro...