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A system of autonomous, computer-controlled power supplies is described in which each voltage is programmed by a local Z8671 microcontroller. Programming information is generated by a remote host computer according to a specified format on a common RS232 bus, and local intelligence decodes information on the bus to determine the output voltage of one or more power supplies. The new system is capable of providing unipolar voltages up to a maximum of +or-500 V, together with bipolar voltages up to +or-150 V. These potentials may be programmed manually or controlled via high-level software from the host, allowing each supply to operate in a number of different modes under the independent supervision of each local microcontroller. Facilities available include the ability to download complex voltage profiles into the memory of one or more supplies, the automatic ramping of one or more voltages between predefined limits and synchronisation of the update of voltage supplies, either with each other or with external events.

Novel circuits for programmable, high-voltage amplifiers are described, which are capable of generating either a single unipolar voltage with a maximum value of 500 V, or a pair of complementary voltages, either of which may range in value from 0 to 300 V. The amplifiers are intended to provide all the potentials necessary for a high-resolution electron spectrometer, which requires large numbers of programmable voltages with modest bandwidth and negligible current capability.

The field of autonomous vehicle dynamics as the theory of such a vehicle in motion is to control the vehicle's properties (vehicle running abilities) in the interaction of the vehicle and it's surroundings. This interaction itself appears through forces acting on a vehicle. To control these forces leads to control the properties of a vehicle in motion such as tractive and velocity properties, fuel consumption, turnability, ride stability and others. This paper proposes a novel theory of autonomous vehicles in motion. This theory allows parallel control of the forces acting on a vehicle, which leads to considerable improvement of the vehicle's running abilities. This paper presents the interrelation between the criteria of vehicle running abilities and output characteristics of vehicle systems, which control the vehicle forces. To optimise a vehicle's running abilities require optimisation of the combinations of forces acting on a vehicle. To provide optimum control of these forces, a methodical investigation of force combinations is proposed to be implemented for the sub-system of wheel patch – powertrain, and for the sub-system of wheel patch – suspension system – steering system – vehicle body. This is a way to research and design autonomous systems, too. To illustrate the process of defining the optimum combination of forces acting on a vehicle in motion, a multiple criteria optimisation problem of the wheel driving forces and, accordingly, output characteristics of wheel drive systems are being considered in this paper. Mathematically, the problem is based on the parallel controlling of tractive and velocity properties, fuel consumption performance, turnability, and ride stability of a vehicle. The problem is then reduced to a single criterion optimisation with limitations of the rest of criteria and limitations of optimised parameters. The development reported in the paper includes an application of the theory to a 12-wheeled highway truck. A mathematical model for studying the truck's running abilities is given based on the inverse dynamics problem. Optimal combinations of the wheel driving forces and a logical control strategy are presented to operate traction control (anti slip regulation – ASR).

A highly flexible system of voltage supplies has been constructed which may be controlled either manually or by an appropriate computer. The interfacing of this system to a high-resolution electron spectrometer is described, together with the operation of a comprehensive voltage-logging facility.

An inexpensive multichannel scaler is described which incorporates a dedicated 6502 microprocessor. The instrument may be interfaced to any computer with an RS232 serial port, and is intended to relieve powerful mini- and microcomputers of the mundane tasks associated with multichannel scaling. The new instrument allows the supporting software to control all the parameters associated with the acquisition of data. It is also capable of performing functions that have previously been impossible with conventional multichannel scalers. The instrument has been successfully applied to a number of high resolution electron impact spectrometers, principally to investigate the excited states of gaseous atoms and molecules.

Three techniques for measuring methotrexate show various cross reactivities with methotrexate-related compounds: “high-pressure” liquid chromatography, by principle, is virtually specific for methotrexate; the enzyme-inhibition assay quantitates methotrexate, methotrexate diglutamate, and methotrexate triglutamate equally well, but has a 10% cross reactivity with 4-amino-4-deoxy-N10-methylpteroic acid and 1% with 7-hydroxymethotrexate; radioimmunoassay shows an equal cross reactivity with methotrexate, 4-amino-4-deoxy-N10-methylpteroic acid, methotrexate diglutamate and triglutamate, and a 5 to 10% cross reactivity with 7-hydroxymethotrexate. Radioimmunoassay almost always yielded the highest values for methotrexate, followed by enzyme-inhibition assay then liquid chromatography. The presence of two methotrexate-related compounds, 7-hydroxymethotrexate and 4-amino-4-deoxy-N10-methylpteroic acid, was confirmed in human urine samples and quantitated in patients’ plasma by liquid chromatography, the respective maximum plasma concentrations being 250 and 16 mumol/L. Materials cross reacting with methotrexate in radioimmunoassay of chromatographic fractions from plasma were also noted in fractions corresponding to methotrexate diglutamate and triglutamate peaks, in quantities estimated to be 47 and 30 nmol/L methotrexate equivalents, respectively. 7-Hydroxymethotrexate is eliminated more slowly than methotrexate and its production increases with dosages of methotrexate.

A data acquisition and control system has been developed that is able to perform real-time optimisation of the potentials that define the operation of an electron spectrometer. The system compensates for voltage drifts and other time-dependent processes that degrade a spectrometer's performance. The optimisation system has been successfully applied to three types of electron spectrometer and typical results are presented, including real-time optimisations in up to eleven dimensions.

Three techniques for measuring methotrexate show various cross reactivities with methotrexate-related compounds: "high-pressure" liquid chromatography, by principle, is virtually specific for methotrexate; the enzyme-inhibition assay quantitates methotrexate, methotrexate diglutamate, and methotrexate triglutamate equally well, but has a 10% cross reactivity with 4-amino-4-deoxy-N10-methylpteroic acid and 1% with 7-hydroxymethotrexate; radioimmunoassay shows an equal cross reactivity with methotrexate, 4-amino-4-deoxy-N10-methylpteroic acid, methotrexate diglutamate and triglutamate, and a 5 to 10% cross reactivity with 7-hydroxymethotrexate. Radioimmunoassay almost always yielded the highest values for methotrexate, followed by enzyme-inhibition assay then liquid chromatography. The presence of two methotrexate-related compounds, 7-hydroxymethotrexate and 4-amino-4-deoxy-N10-methylpteroic acid, was confirmed in human urine samples and quantitated in patients' plasma by liquid chromatography, the respective maximum plasma concentrations being 250 and 16 mumol/L. Materials cross reacting with methotrexate in radioimmunoassay of chromatographic fractions from plasma were also noted in fractions corresponding to methotrexate diglutamate and triglutamate peaks, in quantities estimated to be 47 and 30 nmol/L methotrexate equivalents, respectively. 7-Hydroxymethotrexate is eliminated more slowly than methotrexate and its production increases with dosages of methotrexate.

The induction of 5-aminolaevulinate synthase and of cytochrome P-450 by short-chain aliphatic alcohols was compared in primary cultures of chicken-embryo hepatocytes. Isopropyl alcohol, isobutanol, pentan-1-ol and isopentanol alone caused up to a 4-fold increase in 5-aminolaevulinate synthase, whereas ethanol and propan-1-ol did not. Induction of the synthase by isopentanol was maximal at 8 h, and reached a plateau thereafter, whereas the activity induced by 2-propyl-2-isopropylacetamide continued to increase for 20 h. In the presence of 3,4,3′,4′-tetrachlorobiphenyl, an inhibitor of haem synthesis at the uroporphyrinogen decarboxylase step, synergistic induction of 5-aminolaevulinate synthase was observed with all the alcohols except ethanol. Ethanol, but not isopentanol, decreased the extent of induction of 5-aminolaevulinate synthase by 2-propyl-2-isopropylacetamide and 3,4,3′,4′-tetrachlorobiphenyl (50% decrease at 112 mM-ethanol). Total protein synthesis was not inhibited by ethanol in these cells. The composition of porphyrins was determined after treatment of cells with ethanol, isopentanol or 2-propyl-2-isopropylacetamide. Untreated cells, when incubated with 5-aminolaevulinate for 6 h, accumulated mainly protoporphyrin. However, when cells were pretreated with ethanol, isopentanol or 2-propyl-2-isopropylacetamide for 20 h, and 5-aminolaevulinate was added, 8- and 7-carboxyporphyrins increased, whereas protoporphyrin decreased. The dose responses for induction of either 5-aminolaevulinate synthase or cytochrome P-450 after a 20 h exposure to 3- to 5-carbon alcohols were identical. The results indicate that: simple alcohols can induce both enzymes; hydrophobicity increases their effectiveness; and induction of both enzymes are probably mediated by a common mechanism.

A two-dimensional finite element model of the LOFT LTSF thermocouple assembly was developed to study the thermal response of the thermocouples to the expected temperature transient in the L3-4, 5 and 6 experiments. Subjecting the thermocouple model to a 10 F fluid temperature step change resulted in a .10 second delay before 95% of the step change was observed in the thermocouple temperature response. A thermal analysis was performed on the Loft Test Support Facility (LTSF) small-break thermocouple assembly to evaluate the thermal response of the thermocouples during the upcoming L3-4, 5 and 6 small-break experiments. The thermocouple assembly (see Figure 1) consists of 3 Type K thermocouples placed radially through an 8 inch diameter section on the pressurizer relief line in the LTSF. In support of the upcoming L3-4, 5 and 6 experiments the LTSF will be used to define thermal conditions expected during these tests. The temperature transients these thermocouples are required to follow are very rapid step changes. Therefore, it is necessary that these thermocouples have a short response time in order to follow the temperature transient in this line. A two-dimensional finite element model of the thermocouple assembly was constructed using COUPLE, a finite element heat conduction code. The model was subjected to a step change in fluid temperature expected to be 'seen' by the actual thermocouple and its thermal response observed. Details pertinent to this analysis are contained in appropriate sections of this report.

A computer-controlled, floating power supply is described which is capable of generating a wide variety of complex voltage profiles. The power supply has been successfully used to provide voltages with quadratic and polynomial forms in order to extend the focus range of a zoom lens in a high-resolution electron impact spectrometer.

The electron impact induced fluorescence spectrum of NO at 200 eV was measured for the vacuum UV range (40-170 nm) and the mid-UV range (170-270 nm). The absolute electron impact excitation cross sections are studied by calibrating to the Ly-alpha cross section of H2. The cross section of the N I 120-nm transition by dissociative excitation is found to be 1.73 + or - 0.38 X 10 to the -18th sq cm. Measurements of the cross sections of other features in the vacuum UV and mid-UV are presented. A band model of the far-UV (120-170 nm) is developed. Also, it is found that great care must be taken if NO is the target for relative calibration in the Mid-UV using the molecular branching ratio techniques.

The electron impact induced fluorescence spectrum of NO at 200 eV has been studied from 170 to 270 nm in a crossed beam experiment. By modeling the laboratory spectrum, including the effects of spin-orbit splitting of the ground state, we determined the emission cross sections of the {gamma}({ital A}{sup 2}{Sigma+}{r arrow} {ital X2}{Pi}{sub {ital r}}) and {var epsilon} ({ital D}{sup 2}{Sigma+}{r arrow}{ital X2}{Pi}{sub {ital r}}) band systems. The emission cross section of the {gamma} bands includes a large cascade cross-section contribution from high lying Rydberg states that predominantly populate the {ital v}{prime}=0 level of the {ital A}{sup 2}{Sigma+} state. The {var epsilon} bands are modeled by excitation rates proportional to Franck-Condon factors for direct excitation. One feature is tentatively identifed as the (1,0) {delta} band and permits an estimate of the ({ital C}{sup 2}{Pi}{sub {ital r}} {ital v}{prime}{minus}1{r arrow}{ital X}{sup 2}{Pi}{sub {ital r}} {ital v}=0) emission cross section. Previous low-resloution emission studies of electron impact excitation of the {gamma} bands have not taken into account the heavy spectral blending by the {delta} , {var epsilon}, and {Beta}{prime} bands. A major result of this study indicates great care hdas to be used if NO is taken as a target for relativemore » calibration in the middle ultraviolet (MUV) using the molecular branching ratio technique. The identification of all features in the MUV spectrum allow aeronomers to identify emission features that may arise from electron impact excitation and other chemical processes occurring in the upper atmospheres of the inner planets where NO is a constituent. {copyright} American Geophysical Union 1989« less