Mapping and the Citizen Sensor

The role of citizens in mapping has evolved considerably over the last decade. This chapter outlines the background to citizen sensing in mapping and sets the scene for the chapters that follow, which highlight some of the main outcomes of a collaborative programme of work to enhance the role of citizens in mapping

Změny ve využití zemědlské půdy na Slovensku a v Bulharsku v transformačním období (1990-2006)

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A Study of a Viscoelastic-Friction Damper Using a Lever-Type Displacement Magnifying Mechanism

In the previous paper, the authors proposed a new type of magnetic damper using a lever-type displacement magnifying mechanism and rare-earth magnets. In this paper, a viscoelastic-friction damper and a viscoelastic damper using the lever-type displacement magnifying mechanism and viscoelastic material are proposed in order to obtain a passive damper which gives damping and stiffness within a relative displacement in the region of about 0.1~20 mm. Denoting the magnifying ratio by λ, the damping force and the spring force of the viscoelastic material are increased λ2 times and the friction force is increased λ times by the magnifying mechanism. The trial dampers were made and the resisting force characteristics were measured. To describe the mathematical properties of the viscoelastic material, a four-element viscoelastic model was used, and the parameters of the model were identified using the experimental results. The frequency responses and the seismic responses of a three-dimensional piping system supported by each damper were measured using an electrohydraulic type shaking table. The experimental results are compared with the calculated results obtained by the finite element method (ANSYS), and the effects of vibration suppression of the dampers are discussed

The Future of VGI

In this final chapter, we speculate on future developments in the field of Volunteered Geographic Information (VGI); we focus on how VGI will be a affected by future technological developments, but we also consider issues such as VGI quality, the relationship of VGI with science and citizens, and the impact of VGI in future cities and societies