On-Line Temperature Profile Display System

Combustor development depends on two important factors, namely combustor efficiency and exit temperature profile. A microprocessor based system has been designed to have on-line display of exit temperature profiles during the development testing of a gas turbine engine. The system acquires temperature data from thirty thermocouples around the circumference and at various radial positions of the engine. The signals from the thermocouples are fed to a microprocessor through an analog input subsystem. The microprocessor computes the temperatures, averages the values and plots the radial profile on a colour graphic terminal. On the colour graphic terminal, ideal temperature profiles for various engine speeds are drawn. On the ideal temperature profile, actual temperature profiles are superimposed for various speeds during the testing of a gas turbine engine. In addition, circumferential profile is also plotted in off-line.

Introduction of new computing facilities at the Geological Survey of Greenland

From a cautious start in the use of computers in the early 1970s, the Geological Survey of Greenland has developed complex and varied uses of modern computer facilities for both scientific and administrative tasks. GGU's first computer installation, a noisy TTY connected to the Computing Centre of Copenhagen University by a 110 baud telephone modem, was a selfservice facility which was not easy to use. Over the years, first with use of a PDP-10 with just one Tektronix 4014 graphic terminal and later a succession of increasingly powerful PDP-11s with many terminals, GGU's in-house facilities just kept ahead of the ever increasing demand for computer services. At the same time a number of programs for special tasks were developed on external facilities, because they required larger computers or special facilities. In the 1980s the demands on the computer facilitiesrequiring many different types of programs, including word processing, had grown so large that GGU's in-house system could no longer handle them satisfactorily. A major reorganisation was required, and consequently activities were divided between personal computers (PCs; mainly administrative) and a new central computer (mainly scientific). This development took place in late 1986 with the purchase of 17 new personal computers and a new central computer with accessory peripheral equipment. This has allowed an increasing integration of computer methods into GGU's activities. A brief summary is given below.

Statistical Analysis of Chromatographic Data Obtained by Stripping Techniques

The analysis of gas Chromatographie data is given a theoretical basis in terms of simple probability models. New methods and computer programs have been developed for optimal peak area standardization and increased precision of retention times. Comparisons of chromatograms are simplified by a new type of chromatogram display on a graphic terminal and a semi-automatic method to transform a sequence of chromatograms to cross-sectional data or time series data for each individual compound. The importance of probability models for the measurement errors in a chromatogram is illustrated by a study of ‘stripping intensities' for the organic compounds in a water sample. The estimates of ‘stripping intensities' thus obtained can be used in a systematic search for odourous substances in water.