A damage identification method incorporating the use of inductive learning is presented. Inductive learning is the process of learning from examples. The method utilizes as much dynamic-response data as is available, ordering this information to find the best data with which to discriminate among a set of damage states available for dynamic testing. This method takes into account the inherent variabilities in the damage identification problem. These inherent variabilities include but are not restricted to sensor noise, changes in environmental conditions, slight changes in boundary conditions, and manufacturing differences. The method statistically isolates changes in the dynamic-response characteristics due to damage from these inherent variances. This method is model-independent and can be used to accommodate any sensors, actuators, and data type. In order to demonstrate the method, an experiment was performed on a 12” x 12” x ⅛” aluminum plate hung horizontally from the corners to simulate free-free boundary conditions. The plate was sensed and actuated by two piezoelectric patches mounted diagonally symmetric from one another. A small test mass (2% of the mass of the plate) was placed at four discrete locations, changing the physical properties of the structure. The structural impedance-responses were measured for all of the damage cases for both sensors. This information was processed by the damage identification algorithm to generate rules to which a small amount of data, extracted from a single set of structural impedance-response information, can be applied. The method was able to successfully discriminate all of the damage states from one another as well as to detect the existence of a change in physical properties due to a damaged state of which there was no prior knowledge. / Master of Science

Mosquito pathogenic strains of Bacillus sphaericus are indistinguishable from nonpathogenic strains based on simple phenotypic tests. DNA-DNA hybridizations performed in 1980 placed the 7 pathogens included in that study in a distinct homology group separate from 5 groups of nonpathogens. The overall homology of the pathogenic strains to the species type strain was only 19% indicating that these pathogens should be a separate species. Since the DNA homology study was published in 1980, many more pathogenic strains have been isolated worldwide. Pathogenic strains have been differentiated from other strains of B. sphaericus by rRNA sequencing, fatty acid analysis, and isozyme analysis. The pathogens have been further classified by type of toxin produced, serotyping, and phage typing. I have used random amplified polymorphic DNA (RAPD) fingerprinting to determine the phenetic relationships among 31 pathogenic and 14 nonpathogenic strains of B. sphaericus. DNA Bands in agarose gel migrating the same distance were verified as being homologous using PCR-generated probes made from the RAPD bands. Band patterns resulting from 8 10-mer primers were examined by three coefficients, Jaccard, Dice, and simple matching. Each coefficient was able to distinguish DNA homology groups, although the relative similarity values differed. In agreement with DNA homology studies, pathogenic strains showed less than 10% similarity to nonpathogens using Jaccard and Dice coefficients. This value was 68% based on the simple matching coefficient. Individual serotypes were clearly indicated among the pathogenic strains by each coefficient. This suggests an overall genetic homogeneity among strains within serotypes. It also parallels the uniform toxicity pattern found within each serotype (unlike the toxin diversity found within B. thuringiensis serotypes). These results together with DNA homology data support the establishment of a new species for the pathogenic strains. / Master of Science

Binocular camera fixation refers to the control of camera movements so that the optical axes of two cameras converge at a single point of interest in a three-dimensional scene. This thesis describes the theory and high-level algorithms for a procedure that can locate fixation points in an image pair. The binocular fixation procedure which has been developed here combats several difficult fixation problems that are hard to overcome with traditional approaches. Examples of this are objects lacking in visual texture, scenes with occluding conditions, repeating patterns, and objects which are steeply slanted with respect to the image planes. In order to deal with low-contrast image regions, the system is capable of detecting nearby salient points and shifting attention to a new salient target. Based on local image information, the system adaptively determines an initial window size using an Autoregressive-Moving Average (ARMA) modeling technique. Area-based feature matching is performed using normalized cross-covariance within a multiresolution image hierarchy. Gaussian low-pass filters of increasing spatial resolution are used to construct the hierarchy, and matching is performed in coarse-to-fine order. Finally, affine image warping is used in some cases to reduce the effects of perspective distortion so that area based image comparison is improved. The method presented here can serve as the foundation of a stereo tracking system, and has potential applications in such areas as autonomous vehicle navigation, industrial process control, and visually guided robot manipulation. / Master of Science

Sclerotinia homoeocarpa F.T. Bennett, causal agent of dollar spot on creeping bentgrass (Agrostis palustris Huds.); and Rhizoctonia solani Kihn, causal agent of brown patch on tall fescue (Festuca arundinacea Schreb.), are important pathogens of turfgrass. This research evaluated the ability of twenty bacterial strains of the genus Pseudomonas as potential biological agents for the control of these diseases. Year 1 dollar spot field trials resulted in the identification of five strains performing statistically as well as the recommended fungicide, chlorothalonil. Year 2 trials, using the top strains from Year 1, employed different application schedules and inclusion of a commercial spray adjuvant, Agri-Dex™, Results from Year 2 dollar spot trials indicated that eight strains performed statistically better than the non-treated control. Results from Year 1 and Year 2 of brown patch field trials provided three strains that performed statistically better than the nontreated control during Year 1, but only one strain during Year 2. Laboratory tests performed with all strains and both pathogens showed that demonstration of agar-based inhibition is more difficult to obtain with R. solani. Six strains evaluated using AgriDex™ and S. homoeocarpa in laboratory and greenhouse tests, determined that application with Agri-Dex™ can be more effective than with bacteria alone. Supporting greenhouse tests using the top strains from the S. homoeocarpa field trials to evaluate application timing in controlling dollar spot, indicated less disease with earlier and more frequent applications. With further research, several strains have the potential for disease control on turf, particularly dollar spot, and may reduce the reliance on chemical fungicides. / Master of Science

A novel, zero-current-transition (ZCT) topology of the single-switch three-phase boost PFC rectifier is proposed. The soft transition is achieved with a low-power auxiliary circuit employing an additional switch. The circuit can be used with an IGBT at switching frequencies up to 50. Its operation is analyzed in detail, and design guidelines are provided. The small signal model of the circuit is developed, and voltage mode control is designed. The results are verified on a 4 kW, 50 kHz, experimental ZCT rectifier with an IGBT; total harmonic distortion below 9% and efficiency above 95% were obtained. / Master of Science

This paper analyzes the role of both cooperative and oppositional modes of citizen participation in public decision making related to waste facility siting. Politicians, bureaucrats, and waste industry representatives embrace participatory planning as an equitable and efficient solution to the waste siting dilemma. Ideally, citizen involvement in waste planning would foster solutions both environmentally and economically satisfactory to all stakeholders. To date, however, no clear consensus exists over the instrumental objectives of participatory planning. Participatory planning encompasses a wide spectrum of activities ranging from coalition-building to grassroots development. The broad use of the term “participation” complicates efforts to distinguish between those planning activities which are co-optive and those which are participatory. Guided by two critical questions (‘who’ and ‘why’), the first section of this paper proposes a ‘people centered’ conceptual framework for defining the instrumental goals of participation and for differentiating between co-optive and participatory planning. In the second and third sections, I present a comparative case study of the two predominant modes of participation (cooperative oppositional) currently operating in the United State’s waste facility siting crisis. I use a ‘people centered’ conceptual framework to show that the current cooperative participatory approaches to waste facility siting serve more to facilitate citizen co-optation than participation. I further demonstrate that the grassroots oppositional movement against waste facility siting represents successful participation on the part of the citizens in the face of co-optive attempts on the part of the state and the waste industry. / Master of Urban Affairs

This thesis describes the use of computer vision techniques for distinguishing wooden components in a manufacturing environment. The components considered here are kitchen cabinet doors, which are produced in many different styles and sizes, and travel on a conveyor at 30 feet per minute. An automatic classification system has been developed which can classify doors reliably. The system includes a host computer with video digitizer, two laser sources, and three video cameras to obtain profile images. This thesis describes the careful design of illumination and sensing geometry, the profile-based feature extraction process, and the classification method. The system exists as a laboratory prototype, and has been successfully tested with a large number of samples. / Master of Science

Pretreatment is a common approach for removing color and reducing the organic load of textile dyeing and finishing wastewater. Subsequent aerobic treatment is often employed to complete organic removal as well as remove toxicity and metals. The wastewater from the textile dyeing and finishing industry studied was not treated efficiently and often failed effluent toxicity and metals tests. In this research project, various pretreatment alternatives were studied in an attempt to identify the most efficient and economical method(s). Also, aerobic, biological treatment was performed in bench-scale reactors to determine the biological kinetic coefficients of the wastewater so that the overall efficiency and performance of the biological treatment system might be improved. Effluent toxicity of the wastewater was also evaluated in hopes that improved treatment efficiency would yield subsequent improved effluent toxicity. The performance of a sequencing batch reactor was compared to that of the continuous-flow reactors. In regard to pretreatment with various polymers, coagulation with a blend of inorganic aluminum and a polyamine (AL220, Polymer Systems, Inc.) produced the most economical and efficient results. Subsequent addition of an anionic polymer improved the settling characteristics of the chemical flocs. Color removal ranged from 71-90% and DOC removal averaged 25% with AL220 doses between 400-600 mg/L. Increased sludge ages (θ_c) of the continuous-flow reactors produced improved removal efficiencies. Sludge ages of 8-30 days resulted in an average of 55-68% COD removal. Kinetic analysis produced values of 0.032 d⁻¹ and 0.619 for k_d, and Y, respectively. K_s and k could not be determined accurately. This difficulty was attributed to possible inhibitory effects and a residual, biorefractory COD that was not quantified in this study. The SBR, operated with a cycle time of one day and an average MLSS concentration of 4,266 mg/L, achieved an average 69% COD removal and 59% color removal. Addition of nutrients did not appear to improve these efficiencies. Settling characteristics of the sludge were excellent. Preliminary acute toxicity testing of the SBR effluent and effluent from the 8 day θ_c reactor produced encouraging results. Subsequent chronic toxicity testing of the 15, 20 and 30 day θ_c reactors yielded a maximum No Observed Effect Concentration of 50-75%. / Master of Science

Throughout this century food guide systems (Five Food Groups, Basic Seven, Basic Four, Food Guide Pyramid) have dramatically changed and with the changes the need for adequate assessment measures has changed as well. The objective of the study was to develop and validate two such rapid assessment methods that could possibly be employed as educational devices in nutrition education programs while taking away the need for expensive computer analysis and/or the time consuming, inefficient, and often tedious job of nutrient assessment through various tables of food analysis and composition. College students aged 18-24 served as the sample population and their three-day dietary recalls the data for this study. Each diet was compared to the Food Guide Pyramid (FGP) by using one rapid assessment method scored in two ways (FGP₁ and FGP₂). FGP₁ is a simple point-far-point method based on minimum recommended servings from the Food Guide Pyramid and the FGP₂ score is a weighted method of food groups based on the same criteria. All diets were evaluated in terms of nutrient quantity by computer analysis and translated into mean adequacy ratios for fourteen nutrients (MAR₁) and for seven problem nutrients (MAR₂). The FGP scores (FGP₁ and FGP₂) were then compared to each of the MAR scores (MAR₁ and MAR₂) to test validity by correlation analysis. Results indicate both rapid assessment tools maintain significant correlation (p<000.1) with actual nutrient intakes. A mean FGP₁ score of 10.8 (max. = 15) correlated significantly with a mean MAR₁ score of 0.88 (max. = 1.00)(r = 0.68) and with the MAR₂ score for problem nutrients of 0.83 (max. = 1.00)(r = 0.66). A mean FGP₂ score of 21.3 (max. = 30) correlated significantly with a mean MAR₁ score of 0.88 (max. = 1.00)(r = 0.65) and with the MAR₂ score for problem nutrients of 0.83 (max. = 1.00)(r = 0.63). Results illustrate that the FGP₁ score could be used by the general public individually and in nutrition education programs to help assess diets based on nutrient adequacy. / Master of Science

The aim of Project GeoSim is to develop simulation based introductory geography education software. To maximize the educational benefit of the software, Project GeoSim has developed three user assistance and training methods: Online Help, Printed Manual, and Online Interactive Tutorial. Using a population dynamics simulation called IntlPop as the test-bed, an experiment was conducted comparing the three training methods against each other and against no training at all to find the method from which users complete laboratory exercises most quickly and with the greatest accuracy. Twenty-four participants were randomly assigned to one of four treatments: the three user assistance methods and a control that received no training. Following training, the participants answered nine questions using IntlPop. The control received no training and therefore spent the least time with training material. Of the other training methods, analysis detected no significant difference regarding the time spent with training material. Participants that received training from the online interactive tutorial completed tasks more quickly than those that received no training. However, no significant difference in speed of performance was detected between the online help and printed manual and either the control or online interactive tutorial. Additionally, analysis indicated no significant difference in accuracy of responses among the four treatments. Nor were there any significant differences with respect to subjective satisfaction / Master of Science