Guest Editors' Introduction: Special Section on Concurrent On-Line Testing and Error/Fault Resilience of Digital Systems

2011 ◽  
Vol 60 (9) ◽  
pp. 1217-1218 ◽  
Author(s):  
Cecilia Metra ◽  
Rajesh Galivanche
Keyword(s):  
Special Section ◽  
Digital Systems ◽  
Fault Resilience ◽  
On Line

Simulation and information assessment of TEM and STEM images

1987 ◽  
Vol 45 ◽  
pp. 70-73
Author(s):  
Gary Fan
Keyword(s):  
Data Transfer ◽  
Digital Systems ◽  
Massive Data ◽  
Data Handling ◽  
Schematic Diagram ◽  
Digital Form ◽  
Online Data ◽  
Image Frame ◽  
Digital To Analog Converters ◽  
On Line

Small and moderate digital systems, especially those with computer-microscope interface capabilities and possibly equipped with image frame stores, are being commonly employed in electron microscopy laboratories. The complexity of such systems varies greatly, ranging from those composed of simply a personal computer with minimum interfacing hardwares such as digital to analog converters(DACs) and pulse counters (or ADCs), compact enough to be fitted into a small cart and transported from room to room, to those consisting of image processing systems controlled by mini- or super mini-computers with system-bus interface for massive data transfer, array processors for fast online data handling. Be it simple or complex, such a system allows signals from various sources to be collected and stored in digital form for on-line or off-line manipulation. Fig.1 is a highly schematic diagram of the system currently working in ASU HREM laboratory, on which this work was done.

The on-line use of histogram data for high-speed correction and alignment of electron microscope images

1984 ◽  
Vol 42 ◽  
pp. 556-557
Author(s):  
William Krakow
Keyword(s):  
Power Spectrum ◽  
High Speed ◽  
Direct Memory Access ◽  
Digital Television ◽  
Contrast Transfer Function ◽  
The Past ◽  
High Resolution Tem ◽  
On Line ◽  
Correction Of Astigmatism ◽  
The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

Image registration with a computer driven S.T.E.M.

1978 ◽  
Vol 36 (1) ◽  
pp. 98-99
Author(s):  
A.M.H. Schepman ◽  
J.A.P. van der Voort ◽  
J.E. Mellema
Keyword(s):  
Spot Size ◽  
Scanning Transmission Electron Microscope ◽  
Small Computer ◽  
Structural Studies ◽  
Area Of Interest ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Specimen Area ◽  
On Line ◽  
Minimum Distances

A Scanning Transmission Electron Microscope (STEM) was coupled to a small computer. The system (see Fig. 1) has been built using a Philips EM400, equipped with a scanning attachment and a DEC PDP11/34 computer with 34K memory. The gun (Fig. 2) consists of a continuously renewed tip of radius 0.2 to 0.4 μm of a tungsten wire heated just below its melting point by a focussed laser beam (1). On-line operation procedures were developped aiming at the reduction of the amount of radiation of the specimen area of interest, while selecting the various imaging parameters and upon registration of the information content. Whereas the theoretical limiting spot size is 0.75 nm (2), routine resolution checks showed minimum distances in the order 1.2 to 1.5 nm between corresponding intensity maxima in successive scans. This value is sufficient for structural studies of regular biological material to test the performance of STEM over high resolution CTEM.

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