www.spec t roscopyon l i ne . com T he concept of step-scan mid-infrared inter ferometr y dates back to the 1960s when the first optoelectronically controlled step-scan interferometer was reported (1). In contrast to the linear change of the optical path difference (retardation) in a conventional continuous-scan interferometer, the retardation changes stepwise in a step -scan Fourier transform–...

In this paper, we present a novel approach to support direct access and fast scan operations in a video streaming system. Our approach is based upon reshaping the normal linear encoding structure into some hierarchical tree, along with a proximity-based approximation scheme. Our scheme can support direct access, forward and backward fast scan operations with any speedup factors even for the nor...

Figure 1. Top, An abdominal CT scan with contrast enhancement demonstrates a liver abscess at the lateral segment of the left hepatic lobe, with a linear fish bone (arrow) visible within the abscess. Bottom, A non–contrast-enhanced CT scan in oblique coronal reformation demonstrated that the fish bone was retained in the liver without any sequelae. prolonged courses of oral artesunate to our pa...

Periodic scanning trajectories are designed with minimal harmonic content and fixed linear regions. While minimum harmonic content reduces vibration in mechanical scanners, fixed linear regions eliminate curvature in the scan area. Simulated and experimental results demonstrate less induced vibration than presently used techniques.

In rapid-scan EPR the magnetic field or frequency is repeatedly scanned through the spectrum at rates that are much faster than in conventional continuous wave EPR. The signal is directly-detected with a mixer at the source frequency. Rapid-scan EPR is particularly advantageous when the scan rate through resonance is fast relative to electron spin relaxation rates. In such scans, there may be o...

A Fourier transform spectrometer (FTS) that incorporates a closed-loop controlled, electrothermally actuated microelectromechanical systems (MEMS) micromirror is proposed and experimentally verified. The scan range and the tilting angle of the mirror plate are the two critical parameters for MEMS-based FTS. In this work, the MEMS mirror with a footprint of 4.3 mm × 3.1 mm is based on a modified...