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Application Of Expert Systems In Analytical And Environmental Chemistry, Qiwei Zhu
Application Of Expert Systems In Analytical And Environmental Chemistry, Qiwei Zhu
Digitized Theses
Expert systems are knowledge based computer programs that offer the possibility of combining theories with heuristic expertise, and are therefore capable of solving domain-specific problems. However, little is known about how human knowledge can be effectively and precisely transferred into computer programs. In addition, the lack of a seamless man-machine interface also causes reduced general acceptance of expert systems. In this thesis, the process of knowledge acquisition and the role of the user interface in expert systems are investigated. Results are presented that describe the development of two prototypic expert systems: SPILLexpert and GSMSdiagnosis.;The knowledge domain matrix (KDM) is an …
Diagnostic Expert Systems In Instrumental Analysis, Hai Du
Diagnostic Expert Systems In Instrumental Analysis, Hai Du
Digitized Theses
The acquisition of knowledge is a key phase in the implementation of expert systems yet represents a significant bottleneck. An explanation-based method was applied to knowledge compilation in a GC diagnostic system. A package of macros for Microsoft Excel, MATRIX, was then developed to enable domain experts to build rule-based knowledge bases for expert systems. The MATRIX macros can be used as domain-oriented knowledge acquisition tools that are specialized in coding knowledge concerning the diagnosis of faults in analytical instruments. These knowledge acquisition tools do not require formulation of any certainty factors to resolve conflicts and enable experts in analytical …
Design And Implementation Of Expert Systems In Trace Metal Analysis, Sharbari Lahiri
Design And Implementation Of Expert Systems In Trace Metal Analysis, Sharbari Lahiri
Digitized Theses
Atomic Absorption Expert (AAexpert) is an expert system dealing with automated analysis for trace metals by atomic absorption spectrometry (AAS). This program consists of several stand-alone expert systems, each performing a specific task associated with the analysis.;In this thesis, the design and implementation of three important modules of AAexpert have been studied. These are (a) AAdiagnosis - detects problems associated with analytical data of poor quality and instrument malfunction, (b) AA-Quality Control (AA-QC) - provides a real-time assessment of the quality of measured absorbance values, and (c) AAmethods - selects a method of analysis from a method selection database and …
High-Resolution Core-Level Spectroscopies Of Molecular Silicon Compounds Using Monochromatized Synchrotron Radiation, John D. Bozek
High-Resolution Core-Level Spectroscopies Of Molecular Silicon Compounds Using Monochromatized Synchrotron Radiation, John D. Bozek
Digitized Theses
High-resolution core-level photoabsorption, photoelectron and photoionization mass spectra of numerous substituted silane molecules have been measured in the gas phase around the Si 2p ionization edges using monochromatized synchrotron radiation. Photoabsorption spectra were also measured around the Si 2s ionization edges and the Cl 2p ionization edges of the chlorine-containing molecules. Multiple-scattering X{dollar}\alpha{dollar} calculations were performed to aid in the assignment of the peaks observed in the photoabsorption spectra. The chemical series approach, where the effects of small systematic chemical changes in the composition of the molecule under study on the observed spectra provide useful aids for assignments, has been …
Fundamental Studies Of Interactions Of Water With The Nickel(110) Surface, Brian William Callen
Fundamental Studies Of Interactions Of Water With The Nickel(110) Surface, Brian William Callen
Digitized Theses
The adsorption of water on Ni(110) has been studied by electron stimulated desorption ion angular distributions (ESDIAD), Fourier transform infrared-reflection absorption spectroscopy (FTIR-RAS), low energy electron diffraction (LEED), nuclear reaction analysis (NRA), and work function measurements ({dollar}\Delta\Phi{dollar}). The major findings in this study are: The saturation coverage of the first chemisorbed layer of water is 0.5 water molecules per surface Ni atom or 0.5 ML (1 ML = monolayer = 1.14 {dollar}\times{dollar} 10{dollar}\sp{lcub}15{rcub}{dollar} molecules cm{dollar}\sp{lcub}-2{rcub}{dollar}). The first chemisorbed layer exhibits c(2 x 2) symmetry, and is bonded to the surface monomerically (no evidence of intermolecular hydrogen bonding) with the plane …
Studies In Asymmetric Catalysis, Fan-Chou Xu
Studies In Asymmetric Catalysis, Fan-Chou Xu
Digitized Theses
The homogeneous, asymmetric hydrosilylation of prochiral ketones using chiral Rh catalysts of the amphos, P-N, and diamphos, P-N-N, chelate ligands was studied in both solution and the solid state using X-ray crystallographic and spectroscopic techniques, including {dollar}\sp1{dollar}H and {dollar}\sp{lcub}31{rcub}{dollar}P NMR, Visible, Infra Red, and Mass Spectroscopy. These studies provided a basis for relating the catalyst shape to the optical yield, and allowed the elucidation of a mechanistic scheme for homogeneous asymmetric hydrosilylation. In a certain favourable case, an oxidative addition produce RhHCl(SiCl{dollar}\sb3{dollar})(PPh{dollar}\sb3)\sb2{dollar} was isolated and characterized by a single crystal X-ray diffraction study.;In tests for the hydrosilylation of prochiral ketones …
Aspects Of Sims Matrix Effects In Aluminum-Gallium - Arsenide, William Harvey Robinson
Aspects Of Sims Matrix Effects In Aluminum-Gallium - Arsenide, William Harvey Robinson
Digitized Theses
In secondary ion mass spectrometry (SIMS) the detected ion count rate must be corrected for differences in matrix when depth profiling semiconductor samples with layered structures of different composition. Few published studies of the matrix effect exist and those that have studied the matrices give widely differing factors. The situation is further complicated by secondary ion molecular interferences which can completely mask the ion signal of interest. These problems are examined in this thesis.;The depth distribution of ion implanted samples of {dollar}\sp{lcub}28{rcub}{dollar}Si and {dollar}\sp{lcub}52{rcub}{dollar}Cr in Al{dollar}\sb{lcub}\rm X{rcub}{dollar}Ga{dollar}\sb{lcub}\rm 1-X{rcub}{dollar}As and X equal to 0, 0.066, 0.21 and 0.40 for energies of …
Magnetic And Spectroscopic Studies Of Transition Metal Complexes, Hari Shankar Prasad
Magnetic And Spectroscopic Studies Of Transition Metal Complexes, Hari Shankar Prasad
Digitized Theses
No abstract provided.