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Inductively coupled plasma (ICP) is a promising low pressure, high density plasma source for material processing and is of great importance to modern plasma technology. This thesis summarizes the results of experimental study in a cylindrical ICP by using a single Langmuir probe (LP) and optical emission spectroscopy (OES). <p>The electron energy distribution function (EEDF), which contains important information of ICP plasma and is necessary for an accurate kinetic description of the low-pressure discharges, has been investigated with the Langmuir probe by using the alternating current (ac) method. Measurements were carried out in different gases including both atomic (argon, helium) and molecular (hydrogen, nitrogen) gases. The effects of the external discharge parameters such as gas pressure and radio frequency (rf) power have been investigated and the different mechanisms that influence the formation of the EEDF have been discussed. The radial dependence of the EEPF in the argon plasma has also been evaluated. <p>The average electron energy and electron density have also been obtained by direct measurement of the electron current-voltage (I-V) curve and the result is consistent with the power balance equation.<p> Optical emission spectroscopy has been used to study the importance of neutral gas heating in the ICP. The method used is based upon simulating and fitting the nitrogen emission band (the transition from,uCΠ30'=V to,gBΠ30"=V). Both nitrogen and argon plasmas have been studied separately and significant neutral heating has been found.

Inductively coupled plasma (ICP) is a promising low pressure, high density plasma source for material processing and is of great importance to modern plasma technology. This thesis summarizes the results of experimental study in a cylindrical ICP by using a single Langmuir probe (LP) and optical emission spectroscopy (OES). <p>The electron energy distribution function (EEDF), which contains important information of ICP plasma and is necessary for an accurate kinetic description of the low-pressure discharges, has been investigated with the Langmuir probe by using the alternating current (ac) method. Measurements were carried out in different gases including both atomic (argon, helium) and molecular (hydrogen, nitrogen) gases. The effects of the external discharge parameters such as gas pressure and radio frequency (rf) power have been investigated and the different mechanisms that influence the formation of the EEDF have been discussed. The radial dependence of the EEPF in the argon plasma has also been evaluated. <p>The average electron energy and electron density have also been obtained by direct measurement of the electron current-voltage (I-V) curve and the result is consistent with the power balance equation.<p> Optical emission spectroscopy has been used to study the importance of neutral gas heating in the ICP. The method used is based upon simulating and fitting the nitrogen emission band (the transition from,uCΠ30'=V to,gBΠ30"=V). Both nitrogen and argon plasmas have been studied separately and significant neutral heating has been found.

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Two different types of games are used to measure subjects¡¦ attitudes towards risk and ambiguity in this paper. In GAME 1, subjects are provided with a series of binary choices and a fill-in question for every set of tasks. In GAME 2, subjects are asked to play an auction game. Gains and losses stimulate subjects¡¦ different attitudes toward risk. It also happens when we measure subjects¡¦ attitude toward ambiguity. However, the results of Game 1 and Game 2 lack strong correlation with each other. While answering the series of binary choices in Game 1, subjects are risk averse/ambiguity averse over gains, and risk seeking/ambiguity seeking over losses. While answering the fill-in question in Game 1, subjects are risk neutral/ambiguity neutral over gains, and risk seeking/ambiguity seeking over losses. In GAME 2, we measure the attitude toward risk or attitude by the deviation from the case of neutrality or by risk indexes/ambiguity indexes. Analyzing the deviation, we conclude: (1) In the gains domain with high average probabilities to win, subjects are risk averse/ambiguity averse, but in the case of low average probabilities to win, subjects are risk seeking/ambiguity seeking. On the other hand, in the losses domain with high average probabilities to loss, subjects are risk seeking/ambiguity seeking, but when with low average probabilities to loss, subjects are risk aversion/ambiguity aversion. (2) The correlation between the attitudes toward risk and ambiguity gains is significantly greater than that over losses. (3) In the gains domain, the level of ambiguity aversion of subjects significantly increases with the ambiguous ranges of games. However, in the losses domain, the relation between those two is weak or non-significant. Analyzing the data with the risk indexes and the ambiguity indexes, we have two conclusions identical to the above. However, in the gains domain, the level of ambiguity aversion of subjects significantly increases with the ambiguity range of the games while we have the opposite result in the losses domain.

This research is to improve the efficiency of present prediction factors. It has been tested that many factors have prediction power toward stocks returns. Although the prediction power is not stable, the factors are still valuable. This research analyzes preceding factors by neural network in order to make better use of these factors. Besides, we examine 15 companies respectively and compare the results between neural network and liner regression of those companies. Data are divided into training period and prediction period. We use data of training period to build up our model and test the model by the data from prediction period to verify the prediction powers of the models. The results show neural network has better solution compared to liner regression in both training and prediction period. Neural network is more precision and has less prediction error.

Although galaxy interactions cause dramatic changes, galaxies also continue to form stars and evolve when they are isolated. The dark matter (DM) halo may influence this evolution since it generates the rotational behaviour of galactic disks which could affect local conditions in the gas. Therefore we study neutral hydrogen kinematics of non-interacting, nearby spiral galaxies, characterising their rotation curves (RC) which probe the DM halo; delineating kinematic classes of galaxies; and investigating relations between these classes and galaxy properties such as disk size and star formation rate (SFR). To generate the RCs, we use GalAPAGOS (by J. Fiege). My role was to test and help drive the development of this software, which employs a powerful genetic algorithm, constraining 23 parameters while using the full 3D data cube as input. The RC is here simply described by a tanh-based function which adequately traces the global RC behaviour. Extensive testing on artificial galaxies show that the kinematic properties of galaxies with inclination >40 degrees, including edge-on galaxies, are found reliably. Using a hierarchical clustering algorithm on parametrised RCs from 79 galaxies culled from literature generates a preliminary scheme consisting of five classes. These are based on three parameters: maximum rotational velocity, turnover radius and outer slope of the RC. To assess the relationship between DM content and the kinematic classes, we generate mass models for 10 galaxies from the THINGS and WHISP surveys, and J. Irwin's sample. In most cases mass models using GalAPAGOS RCs were similar to those using traditional ``tilted-ring'' method RCs. The kinematic classes are mainly distinguished by their rotational velocity. We confirm correlations between increasing velocity and B-magnitude, optical disk size, and find earlier type galaxies among the strong rotators. SFR also increases with maximum rotational velocity. Given our limited subsample, we cannot discern a trend of velocity with DM halo properties such as M_halo/M_baryon. Using this strategy on upcoming large databases should reveal relationships between the DM halo and our kinematic classification scheme. If NGC 2841, NGC 3521 and NGC 5055 are understood to have declining RC after further investigation, this cannot be explained by the usual morphology scenarios.

Although galaxy interactions cause dramatic changes, galaxies also continue to form stars and evolve when they are isolated. The dark matter (DM) halo may influence this evolution since it generates the rotational behaviour of galactic disks which could affect local conditions in the gas. Therefore we study neutral hydrogen kinematics of non-interacting, nearby spiral galaxies, characterising their rotation curves (RC) which probe the DM halo; delineating kinematic classes of galaxies; and investigating relations between these classes and galaxy properties such as disk size and star formation rate (SFR). To generate the RCs, we use GalAPAGOS (by J. Fiege). My role was to test and help drive the development of this software, which employs a powerful genetic algorithm, constraining 23 parameters while using the full 3D data cube as input. The RC is here simply described by a tanh-based function which adequately traces the global RC behaviour. Extensive testing on artificial galaxies show that the kinematic properties of galaxies with inclination >40 degrees, including edge-on galaxies, are found reliably. Using a hierarchical clustering algorithm on parametrised RCs from 79 galaxies culled from literature generates a preliminary scheme consisting of five classes. These are based on three parameters: maximum rotational velocity, turnover radius and outer slope of the RC. To assess the relationship between DM content and the kinematic classes, we generate mass models for 10 galaxies from the THINGS and WHISP surveys, and J. Irwin's sample. In most cases mass models using GalAPAGOS RCs were similar to those using traditional ``tilted-ring'' method RCs. The kinematic classes are mainly distinguished by their rotational velocity. We confirm correlations between increasing velocity and B-magnitude, optical disk size, and find earlier type galaxies among the strong rotators. SFR also increases with maximum rotational velocity. Given our limited subsample, we cannot discern a trend of velocity with DM halo properties such as M_halo/M_baryon. Using this strategy on upcoming large databases should reveal relationships between the DM halo and our kinematic classification scheme. If NGC 2841, NGC 3521 and NGC 5055 are understood to have declining RC after further investigation, this cannot be explained by the usual morphology scenarios.