ABSTRACT:Historical building conservation raises two important issues which are documentation and refurbishing. For the recording and documentation, we already have developed 3d laser scanner and such photogrammetry technology those represent a freeze object of virtual reality by digital documentation. On the other hand, the refurbished engineering of historic building is a challenge for conservation heritage which are not only reconstructing the damage part but also restoring tangible cultural heritage. 3D digital cultural heritage models has become a topic of great interest in recent years. One reason for this is the more widespread use of laser scanning and photogrammetry for recording cultural heritage sites. These technologies have made it possible to efficiently and accurately record complex structures remotely that would not have been possible with previous survey methods. In addition to these developments, digital information systems are evolving for the presentation, analysis and archival of heritage documentation.

A new capacitive pressure sensor with very large dynamic range is introduced. The sensor is based on a new technique for substantially changing the surface area of the electrodes, rather than the inter-electrode spacing as commonly done at the present. The prototype device has demonstrated a change in capacitance of approximately 2500 pF over a pressure range of 10 kPa.Index Terms-Capacitive pressure sensor, pressure sensor, sensor dynamic range.

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Accurate motion control for multiaxis motion systems is an important issue for manufacturing industry. In this brief, an adaptive robust control scheme is implemented to synthesize the compensator for tracking and synchronization with the consideration of cross-coupling dynamics among different axes. By using the adaptive strategies, the asymptotic convergence of both tracking and synchronization errors are achieved. The robust control scheme also guarantees the transient performance, tracking errors, and synchronization errors. Experimental results of a three-axis motion system that include system uncertainties and nonlinearity are also illustrated to verify the effectiveness of the proposed approach for different scenarios. The results indicate excellent transient performance as well as both tracking and synchronization accuracies.

This paper present a theoretical evaluation of the application of microelectromechanical technology to reduce banding artifacts in electrophotographic printing systems. The proposed system would consist of arrays of micro-mirrors and micro-lasers replacing conventional laser printing mechanisms. Several advantages of the new system include faster printing speeds, elimination of synchronization problems, improved image quality and lower production costs. Each micro-mirror can be a surface micro-machined piezoelectric cantilever beam with a reflective surface. An analytical model for the cantilever beam describing the dynamic relationship between scan line deflection and the applied voltage is derived. Using a closed-loop feedback control strategy, the effectiveness of the micro-mirror arrays in reducing banding was theoretically evaluated. Calculations show that each micro-mirror should be capable of deflecting the scan line a distance of 50 µm or approximately one 600 dots per inch (dpi) pixel by only using a 2 V voltage potential. Using an actual measured line spacing sequence, the operation of the system was simulated. The results demonstrated good tracking and significant reduction of the low-frequency banding components. Emulated images showed significant reduction in banding for a typical 600 dpi print resolution.

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A novel new ultrahigh-sensitivity pressure and vibration sensor is introduced. The sensor is based on the concept of using a variable ultracapacitor rather than a variable capacitor as a transduction mechanism. The variable ultracapacitor assembly consists of two electrodes on which carbon nano-tubes of a length of 20 m are grown. One electrode is fixed and is fully immersed in the electrolyte, while the other electrode is movable and is positioned outside of the electrolyte. In response to pressure or vibration, an extremely small displacement of 20 m (less than the width of a human hair) submerges the movable electrode into the electrolyte and results in a substantially large variation in capacitance (from zero to 54 F in the present prototype).Index Terms-High-sensitivity transducer, pressure sensor, variable ultracapacitor, vibration sensor.