It is the intention of this thesis to present not only a visual exploration of a design problem, but also to discuss the obviously dialectic relation of the two for me essential basic elements of architecture: type and topos. My architecture education has been shaped in different countries, through different educational systems, and with different teachers and students. This thesis stands as a record of my accumulated experiences and as a description of a personal approach to working with architectural problems. I believe the most important part of an architecture education is the development of one’s own design process. This exposition represents a beginning, / Master of Architecture

Two architects Questions of interaction Questions of decisionmaking Questions of connection “Flickstelle” For an architectural translation see Volume I and Volume II / Master of Architecture

Two architects Questions of interaction Questions of decisionmaking Questions of connection “Flickstelle” For an architectural translation see Volume I and Volume II / Master of Architecture

A thin-film heat flux sensor was used in two transient conduction applications. First it was used in a device for simultaneously determining the thermal conductivity, κ, and the thermal diffusivity, α, of solid materials. The device was heated and then touched to metal samples at room temperature. The thermal properties were characterized based on the heat flux response of the gage, and the change in temperature of the metal surface at a specified distance away from the gage. A finite difference program was developed and used to model the system response. The effect of α was most evident by the time delay in the temperature response on the metal surface. The effect of κ was most evident in the heat flux response after the first few seconds of contact. In the second application, the gage was used in a probe that was cooled and then touched to biological materials. A numerical model was used to demonstrate the effect of tissue blood perfusion on the surface heat flux. Experimental tests were performed on live dogs. Both the numerical model and the experiments showed that increases in blood perfusion could be detected from the transient heat flux measurements. In both applications, this research forms the basis for instrumentation which will be able to measure κ, α, and blood perfusion. / Master of Science

The immunological aspects of the interaction between fish and glochidia were studied using glochidia of the Alabama rainbow mussel (Villosa iris). Tested host species was the rock bass (Ambloplites rupestris) and non-host fishes were common carp (Cyprinus carpio) and goldfish (Carassius auratus). Ouchterlony double-diffusion tests showed that both the host and non-host species expressed a specific humoral response to glochidial antigens after being artificially infested with the parasites. Further microagglutination tests were completed to compare titers of host and non-host fishes which were either uninfested, infested, or reinfested with glochidia. These tests showed that host and non-host species exhibit humoral responses of similar strengths (similar titers) to glochidia. In addition, fishes infested with glochidia had higher titers than uninfested fishes, and reinfested fishes had titers higher than both uninfested and infested fishes. Results indicate that fishes express anamnestic responses to glochidia. Because many host-specific parasites mimic their host’s antigens to avoid full immune attack, I tested for antigen mimicry in glochidia. Goldfish were injected with host (rock bass) and non-host (carp) antigens, in the form of sera, and then re-exposed to glochidial antigens at a later time. This test and other experimental results show no evidence of mimicry of host antigens by glochidia before attachment to host fish. Immunoelectrophoresis (IEP) was used to compare precipitation patterns of host and non-host fishes and to determine whether IEP can be used for identifying suitable hosts for a species of mussel. Although there were subtle differences observed between the precipitation bands of host and non-host fishes using IEP, successful molecular host identification will require more precise electrophoretic methods. The precipitation patterns of glochidial antigens and transformed juvenile antigens (reacted with anti-glochidia fish anti-sera) were compared to determine whether glochidia develop new antigens to avoid a full immune attack during glochidiosis. No precipitation occurred in trials using transformed juvenile antigens; therefore, pre-infestation glochidia and post-infestation juvenile mussels are antigenically different. / Master of Science

Preliminary aircraft design codes requIre a more complete and integrated geometry definition than that used by conceptual design codes. This thesis documents the design and creation of an interactive CAD system which converts the geometry descriptions commonly used in conceptual aircraft design codes to descriptions that meet the requirements of preliminary design systems. In particular, the conversion of ACSYNT Hermite surface data of aircraft models to the non-uniform hi-cubic B-Spline surface representation is addressed. The topics discussed in this thesis include the design and development of an interactive graphics user interface, the design and coding of an intersection method for non-uniform hi-cubic B-Spline surfaces utilizing subdivision techniques and the development of a one-dimensional filleting algorithm for blending surfaces along iso-parametric curves. / Master of Science

Methods of analysis and important design considerations for distributed power systems (DPS) are addressed. A generalized analysis of subsystem interaction is presented. Emphasis is placed on absolute stability and eigenvalue location of the integrated system. Terminal properties of the decoupled subsystems are used in determining the stability criteria. Either analytical models or empirical data may be used in the interaction analysis. Design of EMI filters for a two-stage DPS is comprehensively discussed. A detailed analysis of the effects of input filters on current-mode controlled single-module regulators is given. It is shown that the criteria used to minimize filter interaction for voltage-mode and current-mode controlled regulators are identical. The results of the single-module regulator input filter interaction analysis are extended to the multi-module DPS case. Both line input filters and intermediate bus filters are designed for stability and to minimize interaction with the regulator modules. Implications of non-minimal dimensional subsystems are discussed. The eigenvalues due to parallel interaction are described, and it is shown how appropriate damping can be used to insure their stability. Straight-forward design guidelines are provided for the filters. Interaction of a non-ideal generator source with the DPS is described. This provides a useful application of the general subsystem interaction analysis. Stability is determined from different points in the system, and subsystem impedances are used to qualitatively describe the integrated system eigenvalue location. / Master of Science

A cascading series of control systems is developed which incorporates the molecular events that are currently thought to cause a muscular contraction. The model is developed with the hypothesis that a series of disturbing signals (or inputs) simply propagate faster than the respective controlling signals can correct for them. Transfer functions for each system are developed, with quantification derived for the excitation and the excitation-contraction coupling control systems. These latter systems include the release of acetylcholine into the synapse, the depolarization of the muscle membrane, and the release of calcium ions into the sarcoplasm. Expressions involving the energy processes, as well as the exact mechanism of the power stroke, are also developed. The systems involved are the Krebs cycle, thick and thin filament regulation, and the generation of a cross-bridge power stroke. / Master of Science

The behavior of many systems of practical interest in communications and other areas is well modeled by a single server exponential queueing system in which the arrival and service rates are dependent upon the state of a Markov chain, the dynamics of which are independent of the queue length. Formal solution to such models based on Neuts's matrix geometric approach have appeared frequently in the literature. A major problem in using the matrix geometric approach is the computation of the rate matrix, which requires the solution of a matrix polynomial. In particular, computational times appear to be unpredictable and excessive for many problems of practical interest. Alternative techniques which employ eigenanalysis have been developed. These techniques are polynomially bounded and yield results very quickly compared to iterative routines. On the other hand, the class of systems to which the eigenanalysis based techniques apply have been somewhat restricted. In this thesis, we modify the eigenanalysis approach initially presented in order to remove some of these restrictions. / Master of Science

Seeds of Hypoestes phyllostachya Bak. (polka-dot plant) did not require light to germinate. Sowing method did not affect germination percentage and seedling fresh weight. Bottom heat (24 ± 2°C) promoted seedling growth but did not enhance germination. Stem cuttings did not require bottom heat or rooting hormone to induce adequate adventitious root formation. Three-node cuttings rooted more rapidly and had a more extensive root system than two-node cuttings. Cuttings stuck at a density of 200 per flat rooted less vigorously than those stuck at a density of 135 or 150 per flat. When unrooted cuttings were placed directly into 10 cm pots, root systems were more extensive on cuttings stuck one per pot than on cuttings stuck three per pot. Under intermittent mist, cuttings rooted more extensively than when covered with clear plastic domes. Cultivar differences were observed within both seed and cutting treatments. The optimal concentrations of ancymidol, chlormequat, ethephon, paclobutrazol, and uniconazole to inhibit shoot growth and internode elongation of H. phyllostachya were determined and found to be similar for both seed- and cutting-propagated plants. Daminozide, even at 6000 mg-liter- 1 , was ineffective. Two applications of chlormequat at 1000 mg-liter- 1 resulted in similar height control as one application of 3000 mg.liter- 1• Chlormequat and paclobutrazol are less expensive and were more effective than ancymidol. White cultivars showed greater increase in plant height but less increase in growth index than pink and red ones. Hypoestes phylloslachya was found to be a quantitative (or facultative) short day plant. Seed-propagated plants which attained 16 nodes flowered regardless of photoperiod, but flowering was more rapid under short day than under long days. When applying ethephon at high concentrations, percentage of plants flowering decreased, flowering was delayed, the number of aborted flower buds increased, and most of the plants did not flower within 15 weeks of sowing. The optimal concentrations and time of application for control of flowering for both seed- and cutting-propagated plants were also determined. Plants which received two applications of ethephon at 1500 mg.liter- 1 had a lower percentage of flowering and a greater number of vegetative buds than those received one or no application. / Master of Science