Time-correlated single photon counting (TCSPC) enables acquisition of fluorescence lifetime decays with high temporal resolution within the fluorescence decay. However, many thousands of photons per pixel are required for accurate lifetime decay curve representation, instrument response deconvolution, and lifetime estimation, particularly for two-component lifetimes. TCSPC imaging speed is inhe...

In the management of a modern LAN or campus network, two issues are of key importance, namely network performance and capacity planning. In this paper we report on results from an experimental programme which aims to quantify the performance that can be achieved with a real distributed application running over a range of different network technologies, including Ethernet, ATM, FDDI, and a 100 M...

This paper presents a \dictionary hash" technique that, when presented with a large group of labeled events, can stochastically determine the number of unique labels quickly and with a small amount of memory. This technique is applicable to areas such as signal processing, process monitoring and control, and computer communications network monitoring and control. As a speciic example, this pape...

an engraved counting chamber and a light microscope, have many possibilities of error. The introduction of phase-contrast microscopy by Brecher, Schneiderman, and Cronkite (1953) has greatly facilitated the counting of platelets and improved the accuracy of the results. However, despite this improvement in accuracy the visual method is lacking in one basic essential, namely, speed in producing ...

AIMS To improve bead ingestion counts in Tetrahymena pyriformis by automated image analysis as an alternative to direct-counts. METHODS AND RESULTS Fluorescent latex beads were added to T. pyriformis cultures for ingestion tests. The number of beads ingested by 25 cells was counted directly by epifluorescence microscopy and compared with similar data from image analysis. anova indicated that ...

We discuss the problem of counting the maximum number of distinct states that an isolated physical system can pass through in a given period of time—its maximum speed of dynamical evolution. Previous analyses have given bounds in terms of ∆E, the standard deviation of the energy of the system; here we give a strict bound that depends only on E−E0, the system’s average energy minus its ground st...

The technical realisation and the commissioning experiments of a high-speed X-ray detector based on a quadrant avalanche silicon photodiode and high-speed digitizers are described. The development is driven by the need for X-ray detectors dedicated to time-resolved diffraction and imaging experiments, ideally requiring pulse-resolved data processing at the synchrotron bunch repetition rate. By ...

In x-ray imaging detectors, the signal generated in a detector element is proportional to the number of secondary carriers (such as optical photons or electronhole pairs) generated in the x-ray convertor. Furthermore, the location and statistics of secondary carriers are directly related to the absorbed x-ray energy. Even under monochromatic exposure conditions, there will be a distribution of ...

We discuss the problem of counting the maximum number of distinct states that an isolated physical system can pass through in a given period of time its maximum speed of dynamical evolution. Previous analyses have given bounds in terms of AE, the standard deviation of the energy of the system; here we give a strict bound that depends only on E E0, the system's average energy minus its ground st...