Research has shown that the effect of psychiatric hospitalization on the educational placement of students is a more restrictive educational placement. In a modification of a previous study, students diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) were divided into three groups, mild, moderate, or severe, based on the results of the Conners Behavior Rating Scale. Comparisons between pre and post-hospitalization educational placements were made in order to determine if the effect of psychiatric hospitalization was a more restrictive educational placement for the ADHD students. Student subjects were described by age, sex, I.Q., and reading level, as well as by their psychiatric discharge diagnosis and placement on medication. Results of this study indicated that for the mild and moderate ADHD groups, psychiatric hospitalization resulted in either a more restrictive educational placement or an increase in GED, vocational rehabilitation, private school programs, or school dropouts. For the severe ADHD group, none of the students returned to either regular or special education classes; all the students were enrolled in GED, vocational rehabilitation, private school programs, or had dropped out of school. The variables reading level and severity of the Conners Rating Scale were associated with discharge placement, while I.Q. and gender were not related. The drop-out rate was consistent with the special education drop-out rate which has been previously reported in the literature. Results indicated that for this group of ADHD students, psychiatric hospitalization resulted in either more restrictive educational placements or in withdrawal from public schools, including dropping-out. Legal precedents relating to the use of independent evaluations following a student's discharge from a private facility, as well as a comprehensive review of the history and etiology of ADHD are reviewed and discussed with the results. Implications for further research are also presented. / Ed. D.

A simulation approach was used to determine the effects of multitrait selection on the correlations of sire direct and maternal predicted breeding values across environments. True and predicted direct and maternal breeding values (BV) of sires were simulated for sires evaluated independently in two different environments. Prediction error variances and covariances among direct and maternal BV within environments were required for the simulation. To obtain the necessary input parameters, a variety of MME coefficient matrices were created and inverted to inspect relationship among accuracies and correlations of prediction errors in sire evaluation models. An empirical prediction equation to predict the necessary prediction error covariances was obtained. Divergent, directional and random multitrait selection was then practiced using direct and maternal predicted BV as selection criteria. Samples of 40 sires were randomly obtained from each selected population. Observed correlations between direct and maternal predicted BV across environments were compared to expectations derived from univariate distribution theory. Selection definitely affected the expectations. However, the adjustment developed from univariate theory appeared to accommodate the effect of selection in these expectations. / Ph. D.

Recently it has been concluded that the SiO₄ silicate tetrahedra in crystals behave as rigid bodies. This conclusion is based on analyses of the atomic displacement factors of Si and O atoms obtained from single crystal diffraction experiments wherein the amplitudes of atomic vibrations are ascribed to translational, librational and screw-correlated modes of motion for the entire SiO₄ group. If the displacement ellipsoids are considered to represent time averaged quadratic surfaces of equal configurational potential energy about the mean position of an atom, then an analysis of the these displacements should provide detailed information about the SiO₄ group and the crystal. The apparent SiO bond lengths recorded for silicates over a range of temperatures are typically either invariant or exhibit a contraction with increasing temperature. A rigid-body thermal analysis was completed for the tetrahedra in nine silicates whose structures have been determined over a range of temperatures from 15 K to 1250 K and whose tetrahedra seem to behave as rigid units. The coordinates provided by the analysis yield bond lengths and polyhedral volumes corrected for the librational motion of each silicate tetrahedron. The bond lengths and volumes estimated for tetrahedra with four bridging oxygens seem to increase with temperature at a faster rate than those with four nonbridging oxygen atoms. Those for tetrahedra with two or three nonbridging oxygen atoms tend to increase at an intermediate rate. An analysis of the rigid-body motion of coordinated polyhedra yields a simple but accurate expression for correcting bond lengths for thermal vibrations. Observed anisotropic displacement parameters for Si and O atoms indicate that the SiO₄ tetrahedra in quartz behave as rigid bodies. A configurational potential energy curve, constructed from the librational components of the rigid body motion of the tetrahedra, shows a double well for α quartz and a single well for β quartz when plotted as a function of the displacement of the O atom with temperature. The configurational energetics of α and β quartz are examined with a theoretical potential energy function based on parameters obtained from molecular orbital calculations. The calculations indicate that the temperature behavior of a quartz is governed by the energetics of the SiOSi angle, in contrast to β quartz which is governed by the energetics of the SiO bond. The mechanism of the α ⇌ β transition is examined in terms of the experimental and modeled configurational potential energy curves. Evidence for the proposal that π bonding is the driving mechanism for the transition is lacking. Structural and volume compressibility data for α-cristobalite were determined by single crystal X-ray diffraction methods for pressures up to ~1.6 GPa, where cristobalite undergoes a reversible phase transition. The bulk modulus was determined to be 11.5(7) GPa with a pressure derivative of 9(2). The SiOSi angle shows a greater decrease than observed for quartz and coesite while the SiO bond lengths and the OSiO angles remain essentially unchanged. The responses of V/V₀ and SiOSi angle to pressure for the silica polymorphs are compared and it is found that the percentage decrease in the volume is linearly correlated with the percentage decrease in the SiOSi angle, regardless of the framework structure type. A mathematical modeling of the energies of the structural changes that are induced by pressure suggests that the contribution to the total energy ascribed to Si0Si angle bending terms is the same in quartz and cristobalite. / Ph. D.

Inductors and transformers constitute two important magnetic components In RF and power hybrids electronic circuitry. Thick film inductors have been subject of extensive research in recent years because they significantly reduce the weight and size, and increase the frequency of operation of electronic circuits. The research work in this dissertation is aimed at the formulation of thick film ferrite pastes and ferrite epoxies and the design, construction, and evaluation of thick film spiral inductors. Wideband characterization (DC - 2GHz) of ferrite pastes, ferrite epoxies, and ferrite substrates is performed using two techniques. These techniques are based on current image and transmission line (coaxial cavity) concepts for low (DC-IOOMHz) and high (50MHz-2GHz) frequency regions, respectively. They are used to evaluate the permeability spectra of formulated and commercially available thick film magnetic materials in respective frequency ranges. A method to numerically calculate the inductance of thick film circular spiral inductors based on modeling the spiral as concentric circles is presented. A novel method for fine as well as coarse tuning of thick film inductors is also introduced. The tunable inductors are constructed using formulated ferrite epoxies and magnetic cores. The method of analysis of variance is used to investigate the variation significance of tunable inductors. Finally, chemical and mechanical properties of developed magnetic materials are discussed. The studied properties include, glass transition temperature, degradation temperature, thermal coefficient of expansion, adhesion, particle-size distribution and particle densification , grain size, and compositional constituents of the magnetic materials. / Ph. D.

The integrated design of a structure and its control system was treated as a multiobjective optimization problem. Structural mass, a quadratic performance index, and the flutter speed constituted the vector objective function. The closed-loop performance index was taken as the time integral of the Hamiltonian. Constraints on natural frequencies and aeroelastic damping were also considered. Derivatives of the objective and constraint functions with respect to structural and control design variables were derived for a finite element beam model of the structure and constant feedback gains determined by Independent Modal Space Control. Pareto optimal designs generated for a simple beam and a tetrahedral truss demonstrated the benefit of solving the integrated structural and control optimization problem. The use of quasi-steady aerodynamic strip theory with a thin-wall box beam model showed that the integrated design for a high aspect ratio, unswept, straight, isotropic wing can be separable. Finally, an efficient modal solution of the flutter equation facilitated the aeroelastic tailoring of a low aspect ratio, forward swept, composite plate wing model. / Ph. D.

Meta-diisopropylbenzene is reacted with propylene over the acid form of the molecular sieves SAPO-5, mordenite, offretite, beta, hexagonal and cubic faujasite (hex and FAU), L, SAPO-37, and an amorphous silica-alumina at temperatures around 463 K in a flow-type fixed-bed reactor. A small amount of cracking is observed. The main reactions of meta-diisopropylbenzene are isomerization and alkylation. This alkylation is proposed as a new test reaction to characterize the effective size of the voids in larger pore (12 T-atom rings or above) molecular sieves by measuring the amount ratio of formed 1,3,5- to 1,2,4-triisopropylbenzene. In most cases, this ratio increases with the increasing effective void size of the molecular sieves in the order: SAPO-5 < mordenite < offretite < beta < hex ≈ FAU < L < SAPO-37 < amorphous silica-alumina. Since samples with the FAU topology show lower selectivities to 1,3,5-triisopropylbenzene than the mesoporous, amorphous silica-alumina, pore curvature has an influence on alkylation selectivity even for voids of 13 A size. / Ph. D.

An investigation was conducted to design instruments to directly measure skin friction along the chamber walls of supersonic combustor models. Measurements were made in a combustor at the General Applied Science Laboratory (GASL) and in the Direct Connect Arcjet Facility (DCAF) supersonic combustor at the NASA AMES Research Center. Flow conditions in the high enthalpy combustor models ranged from total pressures of 275-800 psia (1900-5550 kPa) and total temperatures from 5800-8400 R (3222-4667 K). This gives enthalpies in the range of 1700-3300 BTU/Ib_m (3950-7660 KJ/kg) and simulated flight Mach number from 9 to 13. A direct force measurement device was used to measure the small tangential shear force resulting from the flow passing over a non-intrusive floating element. The floating head is mounted to a stiff cantilever beam arrangement with deflection due to the shear force on the order of 0.0005 in (0.0125 mm). This small deflection allows the balance to be a non-nulling type. Several measurements were conducted in cold supersonic flows to verify the concept and establish accuracy and repeatability. This balance design includes actively controlled cooling of the floating sensor head temperature through an internal cooling system to eliminate nonuniform temperature effects between the head and the surrounding chamber wall. This enabled the device to be suitable for shear force measurement in very hot flows. The key to this device is the use of a quartz tube cantilever with strain gages bonded at orthogonal positions directly on the surface at the base. A symmetric fluid flow was developed inside the quartz tube to provide cooling to the backside of the floating head. Bench tests showed that this did not influence the force measurement. Numerical heat transfer calculations were conducted for design feasibility and analysis, and to determine the effectiveness of the active cooling of the floating head. Analysis of the measurement uncertainty in cold supersonic flow tests show that uncertainty under 8% is achievable, but variations in the balance cooling during a particular test raised uncertainty up to 20% in these very hot flows during the early tests. Improvements to the strain gages and balance cooling reduced uncertainty for the later tests to under 15%. / Ph. D.

The goal of this work is to present an advanced query processing algorithm formulated and developed in support of heterogeneous distributed database management systems. Heterogeneous distributed database management systems view the integrated data through an uniform global schema. The query processing algorithm described here produces an inexpensive strategy for a query expressed over the global schema. The research addresses the following aspects of query processing: (1) Formulation of a low level query language to express the fundamental heterogeneous database operations; (2) Translation of the query expressed over the global schema to an equivalent query expressed over a conceptual schema; (3) An estimation methodology to derive the intermediate result sizes of the database operations; (4) A query decomposition algorithm to generate an efficient sequence of the basic database operations to answer the query. This research addressed the first issue by developing an algebraic query language called cluster algebra. The cluster algebra consists of the following operations: (a) Selection, union, intersection and difference, which are extensions of their relational algebraic counterparts to heterogeneous databases; (b) Normal-join and normal-projection which replace their counterparts, join and projection, in the relational algebra; (c) Two new operators embed and unembed to restructure the database schema. The second issue of the query translation was addressed by development of an algorithm that translates a cluster algebra query expressed over the virtual views to an equivalent cluster algebra query expressed over the conceptual databases. A non-parametric estimation methodology to estimate the result size of a cluster algebra operation was developed to address the third issue described above. Finally, this research developed a query decomposition algorithm, applicable to the relational and non-relational databases, that decomposes a query by computing all profitable semi-join operations, followed by the determination of the best sequence of join operations per processing site. The join optimization is performed by formulating a zero-one integer linear program that uses the non-parametric estimation technique to compute the sizes of intermediate results. The query processing algorithm was implemented in the context of DAVID, a heterogeneous distributed database management system. / Ph. D.

According to the predominant image, applied science is a linear, sequential process, the application of science. First scientists or applied scientists develop knowledge that satisfies the epistemic criteria of science, and applied scientists then find ways to use this certified knowledge to solve society's problems. There is, therefore, a sharp distinction between epistemic or scientific criteria and social criteria. The historical development of the applied ecological discipline called range science or range management demonstrates instead that applied science is a simultaneous process. Range science developed at a time when America increasingly looked to science to solve social, political, and economic problems in the hope that science's ability to predict could provide the basis for organization and rational management. The institutionalization of range science industrialized ranching. Ranchers appealed to a variety of traditional American values in response to this industrialization, but in the new context surrounding ranching those values had become illegitimate. From the outset, range science acquired a dual orientation toward both the epistemic criteria of science and the social criteria of society. That dual orientation introduced a tension into range science because it was not obvious how range scientists should satisfy both sets of criteria simultaneously. Researchers in different institutional contexts developed distinct resolutions to that tension. The most significant difference between the institutions were their political objectives and a difference in the power relations between range researchers and their audiences. Those institutional contexts defined the social criteria and provided the background to judge the acceptability of particular resolutions of the tension, in the process providing the motivation and justification for range science. Nevertheless, range science was not just politics by another means because range scientists also satisfied the epistemic criteria of science. The distinction between epistemic and social criteria therefore did not exist in the historical development of range science because range scientists simultaneously satisfied the epistemic criteria of science and the social criteria that flowed from different political objectives and different power relations between researchers and ranchers. / Ph. D.

The cell extract protein content of acetate- and methanol-grown Methanosarcina thermophila was examined by two-dimensional polyacrylamide gel electrophoresis to determine the extent of regulation by the growth substrate. More than 100 mutually-exclusive spots were present in acetate- and methanol-grown cells suggesting a high degree of regulation. Spots corresponding to acetate kinase, phosphotransacetylase, and the five subunits of the nickel-containing carbon monoxide dehydrogenase (CODH) complex were identified in acetate-grown cells. The nickel-containing methyl coenzyme M methylreductase from acetate-grown M. thermophila was purified 16-fold from a cell extract to apparent homogeneity. The enzyme had a native molecular weight of between 132,000 and 141,000 and contained three subunits with a configuration of a1B1y1-. The as-isolated enzyme was inactive, but could be reductively reactivated by either titanium (III) citrate or reduced ferredoxin. Reactivation with ferredoxin was a simplification over previously reported reactivation systems. ATP stimulated, but was not required for reactivation. The CO dehydrogenase enzyme complex from M. thermophila was purified and separated into its respective components: the CO-oxidizing nickel/iron-sulfur (Ni/Fe-S) component and the cobalt-containing corrinoid/iron sulfur (Co/Fe-S) component. EPR spectroscopy and spectroelectrochemical titration of the Fe-S centers of the Ni/Fe-S component indicated the presence of two low-potential [4Fe-4S]2+/1+ centers and third high-potential center whose Fe-S configuration is unknown. When reduced with CO, the NilFe-S component exhibited a previously unobserved Ni-Fe-C EPR signal. The Co/Fe-S component contained one [4Fe-4S]2+/1+ cluster, and the as-isolated corrinoid in the component was in the base-off conformation suggesting that modulation of the electron density of the cobalt ion may result in a modified reactivity of the active site of the corrin. The CODH enzyme complex and isolated Co/Fe-S component reductively dechlorinated trichloroethylene to cis-dichloroethylene, trans-dichloroethylene, 1,1-dichloroethylene, vinyl chloride, and ethylene. Factor III also catalyzed the dechlorination of trichloroethylene when in the presence of titanium (III) citrate. Reconstitution of the Co/Fe-S component with the CO-reduced NilFe-S component also allowed dechlorination demonstrating an electron transfer from the reduced Ni/Fe-S component to the Co/Fe-S component. / Ph. D.