Integrated adaptive filtering and design for control experiments of flexible structures

A novel method is presented of identifying a state space model and a state estimator for linear stochastic systems from input and output data. The method is primarily based on the relations between the state space model and the finite difference model for linear stochastic systems derived through projection filters. It is proven that least squares identification of a finite difference model converges to the model derived from the projection filters. System pulse response samples are computed from the coefficients of the finite difference model. In estimating the corresponding state estimator gain, a z-domain method is used. First the deterministic component of the output is subtracted out, and then the state estimator gain is obtained by whitening the remaining signal. Experimental example is used to illustrate the feasibility of the method

Management of Isolated Gastric Varices by Devascularization and Proximal Gastrectomy in Cirrhotic Patients

Twenty patients with liver cirrhosis were treated by surgery for bleeding from isolated gastric varices. The presence of tortuous and engorged gastric veins connecting with a large splenorenal shunt was demonstrated by transhepatic portography in all patients. The surgical procedures consisted of splenectomy, proximal gastrectomy, paragastric devascularization, and ligation of the splenorenal shunt. Sixteen patients survived the surgery. Four deaths were caused by emergency operation for uncontrollable hemorrhage in extremely poor risk patients. Of the 16 survivors, 15 had been followed wth endoscopy and portography for a mean period of 42 months. The other one died of hepatocellular carcinoma three years after surgery. There was no bleeding episode during the period of follow-up in these patients. Recurrent esophageal varices of mild degree were documented by endoscopy and portography in three patients. Portography demonstrated that several newly formed retroperitoneal veins arising from the junction of the portal and superior mesenteric veins joined to form recurrent varices in these three patients. There was no significant change of the mean portal venous pressure before and after surgery. Our data reveals that elective surgery may provide satisfactory results in patients with isolated gastric varices. Transhepatic portography is the method of choice in radiologic investigation for prominent gastric varices

Biogeochemistry of Organotin and Organolead compounds in a Forested Catchment in NE-Bavaria, Germany

Organotin-compunds (OTC) and Trimethyllead (TML) have a higher toxicity than their corresponding inorganic forms and may affect the functioning of ecosystems. Little is known about their behaviour and fate in the terrestrial environment. The goal of this thesis was to investigate the biogeochemistry of OTC (methyltin, butyltin and octyltin compounds) and TML in a forested catchment, especially their input and output budget. The occurrence of OTC, TML, Sntotal and Pbtotal in the atmosphere, soils, precipitation, and runoff in a forested ecosystem in NE-Bavaria, Germany were investigatedand the inputs and outputs in the solute phase determined. In addition, their ad-desorption and transformation (degradation) in forest soils was studied using batch experiments and long term incubations, respectively. OTC and TML concentrations in the gas phase during April to June 2003 was on average 110 pg Sn m3 and 0,34 pg Sn m3. Tri-, di-substituted and octyl species were the dominant OTC in the gas phase. In aerosols, only butyltin compounds, dimethyltin and monomethyltin (= di- > tri-substituted OTC, and the gas / particle partition coefficients were mono- >> di- >> tri-substituted OTC. Aerosol particles serve as a sink for OTC in the atmosphere, especially for monomethyltin and monobutyltin...thesi

Single-Mode Projection Filters for Modal Parameter Identification for Flexible Structures

Single-mode projection filters are developed for eigensystem parameter identification from both analytical results and test data. Explicit formulations of these projection filters are derived using the orthogonal matrices of the controllability and observability matrices in the general sense. A global minimum optimization algorithm is applied to update the filter parameters by using the interval analysis method. The updated modal parameters represent the characteristics of the test data. For illustration of this new approach, a numerical simulation for the MAST beam structure is shown by using a one-dimensional global optimization algorithm to identify modal frequencies and damping. Another numerical simulation of a ten-mode structure is also presented by using a two-dimensional global optimization algorithm to illustrate the feasibility of the new method. The projection filters are practical for parallel processing implementation

Large planar maneuvers for articulated flexible manipulators

An articulated flexible manipulator carried on a translational cart is maneuvered by an active controller to perform certain position control tasks. The nonlinear dynamics of the articulated flexible manipulator are derived and a transformation matrix is formulated to localize the nonlinearities within the inertia matrix. Then a feedback linearization scheme is introduced to linearize the dynamic equations for controller design. Through a pole placement technique, a robust controller design is obtained by properly assigning a set of closed-loop desired eigenvalues to meet performance requirements. Numerical simulations for the articulated flexible manipulators are given to demonstrate the feasibility and effectiveness of the proposed position control algorithms

Projection filters for modal parameter estimate for flexible structures

Single-mode projection filters are developed for eigensystem parameter estimates from both analytical results and test data. Explicit formulations of these projection filters are derived using the pseudoinverse matrices of the controllability and observability matrices in general use. A global minimum optimization algorithm is developed to update the filter parameters by using interval analysis method. Modal parameters can be attracted and updated in the global sense within a specific region by passing the experimental data through the projection filters. For illustration of this method, a numerical example is shown by using a one-dimensional global optimization algorithm to estimate model frequencies and dampings

Species Delimitation and Diversification History in Rhinoceros Beetles: How Many and Why So Many Species?

I address two grand challenges in biology – species delimitation and speciation process. Additionally, I attempt to bridge the gap between macro- and micro-evolutionary studies. The characteristics of two groups of rhinoceros beetles (genus Dynastes and Xylotrupes) make them ideal for addressing these questions – geographically widespread taxa with local morphological forms – also make them challenging to study. These groups exhibit inconsistency in taxonomic designations and their geographic distributions imply complex historical processes in their diversification process. My research highlights both the power, but also the necessity, of an integrative framework that considers different data types, as well as quantitative approaches to test different hypotheses about species boundaries and the diversification process. For example, my first chapter revealed the arbitrariness in taxonomic decisions, even between closely related taxa from the same lineage, by demonstrating that species boundaries were statistically equivalent among taxa even though some were assigned as subspecies. By establishing this taxonomic foundation, my studies on the effects of ecological and geographic isolation on species diversification in the following chapters avoid the biases introduced by taxonomic ambiguity and inconsistency. In my second chapter, I show that the effects of habitat stability/instability outweighs the contributions of geological events that connect previously isolated biotas in promoting rapid diversification in Hercules beetles. Following the general theme of the contribution of different barriers to divergence, in Chapter 3 I test whether their effects are similar across different levels of biological organization – that is, in the structuring of patterns of genetic diversity among population, species, and faunal communities. This work shows that oceanic barriers between landmasses in the Indo-Australian Archipelago delineates zoological regions by structuring distinct faunal communities and promotes population subdivision in Xylotrupes beetles. However, the rate of species diversification is associated with shifts in forest fragmentation across geological times. As such, this work highlights the decoupling of processes contributing to micro- and macroevolutionary patterns, which only became evident because of my integrative approach that involves consideration of alternative mechanisms and study of divergence at multiple levels of biodiversity.PhDEcology and Evolutionary BiologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/133411/1/huangjp_1.pd

The great American biotic interchange and diversification history in Dynastes beetles (Scarabaeidae; Dynastinae)

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134267/1/zoj12393.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134267/2/zoj12393_am.pd

Phylogenetic Studies of the United States Bluetongue Viruses and Characterization of the Viral VP4 Protein

Bluetongue virus (BTV) is transmitted by arthropod vectors and causes bluetongue disease with serious economic loss in many regions of the world. The replication mechanism of bluetongue virus is still not clear. To have a better understanding regarding the viral replication, the function of each individual protein has to be identified. This study used molecular biology techniques to investigate the function of the inner core protein VP4. The M1 genes of United States bluetongue virus serotypes-2, -10, -11, -13, and -17 were cloned and sequenced. The length of each of the five M1 genes is 1981 nucleotides. The coding region of the M1 gene, which encodes the VP4 protein, possesses an open reading frame with an initiation codon (ATG) at nucleotides #9-11 and a stop codon (TAA) at nucleotides #1941-1943. This open reading frame encodes a protein of 644 amino acid residues with a predicted molecular weight of about 75 kDa. A potential leucine zipper motif was detected near the carboxyl terminus of the deduced VP4 amino acid sequence. The phylogenetic analysis of bluetongue viruses using the sequences of these five cognate M1 genes is consistent with the results of previous phylogenetic studies. Serotypes-10, -11, -13, and -17 are closely related and serotype-2 is the most distantly related among the five US BTV serotypes. Heterologously expressed bluetongue virus VP4 protein was purified to near homogeneity. Six linear epitopes of VP4 were mapped at both termini and in the middle of the protein. By using enzyme-linked immunosorbent assay and peptide competition assay, six linear epitopes were found to be surface accessible. The VP4 protein was shown to be an oligomer by chemical cross-linking. VP4 protein was identified as a ssRNA-binding protein. The VP4 protein has binding activity towards both capped and non-capped ssRNA. RNA-binding activity was not specific to BTV ssRNA. A leucine-zipper motif of VP4 is not required for RNA-binding activity. One RNA-binding domain was mapped between amino acid residues #112-158 by a Northwestern assay and by deletion mutant analysis. Using sequence-specific synthetic peptides corresponding to VP4 in the arginine-and lysine-rich regions, four potential ssRNA-binding domains of VP4 protein were mapped

Fundamental studies of grafting reactions in free radical copolymerization

A new method of measuring the efficiencies of free radical grafting reactions is presented. This technique utilized the compositional analysis capability of dual detector (UV and RI) gel permeation chromatography in which the mixture of polymer resulting from the graft copolymerization reaction is also subjected to separation by molecular size. Samples of the reaction mass drawn from a reactor are diluted with GPC carrier solvent and injected directly into the chromatograph without any other preparative step. Grafting efficiency, graft ratio, molecular weight distributions, and the frequency of graft chains along the backbone polymer are simultaneously determined. This simple technique overcomes the need to separate or purify the polymer mixture prior to analysis, as required for most other methods. Graft site initiation occurs by primary radical and/or polymeric radical attack on the backbone polymer. Graft site can be generated by either chain transfer reaction or double bond addition mechanism. The controlling mechanism is determined by the structure of the backbone and the activity of the free radicals. The efficiency of incorporation of monomer into the graft chains depends upon the graft site initiation mechanism, the mode of polymer chain termination (recombination or disproportionation) and chain transfer reactions. A series of kinetic studies of different grafting systems results in a series of uniquely different expressions describing the graft efficiency, $\phi$. The dependency of $\phi$ upon monomer, initiator and backbone concentrations is different from case to case. A complete kinetic model is also established, which is capable of predicting reaction rate, graft efficiency, graft frequency, graft ratio, and molecular weight averages and distributions. Simulations are provided to compare predicted results with experimental data for each system