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Articles 7021 - 7050 of 7353

Full-Text Articles in Physical Sciences and Mathematics

Benthic Foraminifera And Paleoenvironments Of The Arcola Limestone Member Mooreville Formation (Campanian) In Eastern Mississippi And Western Alabama, Julia K. Palmer Jul 1986

Benthic Foraminifera And Paleoenvironments Of The Arcola Limestone Member Mooreville Formation (Campanian) In Eastern Mississippi And Western Alabama, Julia K. Palmer

OES Theses and Dissertations

Eighty-one species of benthic foraminifera have been recovered from chalky marls of the upper Mooreville Formation including the Arcola Limestone Member, and the basal Demopolis Formation located in five sections in east-central Mississippi and west-central Alabama. These species have been described and seventy-nine illustrated. Analysis of the environmental or depth preferences of abundant species together with planktonic percentages and benthic species diversity, indicates that the chalky marls were deposited in a broad shallow shelf sea (subtidal conditions less than 100m) greatly influenced by open ocean conditions. The benthic assemblage is composed of a mixture of typically neritic and bathyal species …


A Histological Investigation Of The Larval Mandibular Organ In The Mud Crab Rhithropanopeus Harrisii (Gould) (Crustacea Decapoda Xanthidae), Lore Lynn Hantske Jul 1986

A Histological Investigation Of The Larval Mandibular Organ In The Mud Crab Rhithropanopeus Harrisii (Gould) (Crustacea Decapoda Xanthidae), Lore Lynn Hantske

OES Theses and Dissertations

Mandibular organs of the mud crab, Rhithropanopeus harrisii (Gould) were histologically located and followed throughout the larval cycle to determine their role in metamorphosis. Specimens from each day of the four larval stages and the megalopa stage were embedded in paraffin, sectioned at 8 μm, stained and observed under the microscope for the mandibular organs. The organs were located in the mandibular area of second, third and fourth stage larvae. The organs were probably present in the first stage zoeae and in the megalopa stage, although the

techniques of the study were not sensitive enough to observe them. The …


Mössbauer Spectroscopic Studies Of Hemoglobin And Its Isolated Subunits, G. R. Hoy, D. C. Cook, R. L. Berger, F. K. Friedman May 1986

Mössbauer Spectroscopic Studies Of Hemoglobin And Its Isolated Subunits, G. R. Hoy, D. C. Cook, R. L. Berger, F. K. Friedman

Physics Faculty Publications

Samples of 90% enriched 57Fe hemoglobin and its isolated subunits have been prepared. Mössbauer spectroscopic measurements have been made on three such samples. Sample one contained contributions of oxyhemoglobin, deoxyhemoglobin, and carbonmonoxyhemoglobin. This sample was studied from a temperature of 90 K down to 230 mK. Measurements were also made at 4.2 K using a small applied magnetic field of 1.0 T. In general, the measured quadrupole splittings and isomer shifts for each component agreed with previous measurements on single component samples in the literature, and thus demonstrated that chemically enriched hemoglobin has not been altered. The second and …


Generic Specifications In Lil And In Ada Via Analogies, George Chester Harrison May 1986

Generic Specifications In Lil And In Ada Via Analogies, George Chester Harrison

Computer Science Theses & Dissertations

We address the problem of .making verifiable specifications in generic program units in the Ada Programming Language*. We illustrate the methodologies of LIL proposed by Joseph Goguen and Justify the use of such a specification languages using analogy programming originally proposed by Nachum Dershowitz. The work in these areas is new and noticeably incomplete. We address our concern about the reusability of Ada software in a programming environment that includes a specification language like LIL. * Ada is a registered trademark of the U.S. Government (Ada Joint Program Office)


Magnesium, Copper And Zinc Concentrations In Blood From Children With Diabetes Mellitus, Linda Lowers Jenkins Apr 1986

Magnesium, Copper And Zinc Concentrations In Blood From Children With Diabetes Mellitus, Linda Lowers Jenkins

Chemistry & Biochemistry Theses & Dissertations

Trace element levels in blood from diabetic children were investigated and compared to control children. Plasma, erythrocyte, mononuclear and polymorphonuclear cells were analyzed for magnesium, copper, and zinc content. Leukocyte separation was performed by density gradient centrifugation on Ficoll-Hypaque, followed by washing steps to remove platelet contamination and hypotonic lysis to remove red cell contamination. Polarized Zeeman-effect atomic absorption spectroscopy was used for trace metal analysis.

Decreased plasma magnesium levels were observed in the diabetic children. This finding is well documented and probably due to increased urinary magnesium loss from glycosuria. Lymphocyte magnesium levels in the diabetic children were also …


Patterns Of Diurnal Vertical Distribution And Dispersal-Recruitment Mechanisms Of Decapod Crustacean Larvae And Postlarvae In The Chesapeake Bay, Virginia And Adjacent Offshore Waters, Robert Copeland Maris Apr 1986

Patterns Of Diurnal Vertical Distribution And Dispersal-Recruitment Mechanisms Of Decapod Crustacean Larvae And Postlarvae In The Chesapeake Bay, Virginia And Adjacent Offshore Waters, Robert Copeland Maris

OES Theses and Dissertations

Larval dispersal and subsequent postlarval recruitment are extremely significant processes affecting the maintenance of ecologically and economically important populations of decapod crustaceans. Vertical positioning in the water column plays a major role in the particular strategies of retention or expulsion with immigration.

The present study was undertaken to investigate variations in vertical distribution according to temporal (diurnal), spatial (estuarine, transition, oceanic), ontogenetic (larval stages, postlarvae) and various environmental factors (especially light, temperature, salinity and tides). Also, effects of vertical positioning on dispersal-recruitment were examined.

Three stations were established for the present study: York River mouth (estuarine) (37°12'N, 76°16'W); Chesapeake Bay …


Laser Pump And Probe Excited State Absorption Measurements, Shawpin Jong Apr 1986

Laser Pump And Probe Excited State Absorption Measurements, Shawpin Jong

Electrical & Computer Engineering Theses & Dissertations

A pump and probe technique was used to investigate triplet-triplet excited state absorption in solutions of the scintillators 2,5 diphenyloxazole (PPO) and 2,1 naphthyl,5 phenylzole (a-NPO) in several solvents.

KrF excimer radiation (248 nm) was used to pump the samples under investigation as well as a tunable dye laser which was used as the probe. Time-resolution was obtained by changing the optical path difference between the pump and probe beams.

Transient excited state absorption was measured in a wide spectral region between 330 nm and 600 nm, showing a peak at 400 nm for PPO solutions, and two …


Disease Incidence Of Demersal Finfishes From The Southern And Western Branches Of The Elizabeth River, Virginia, Randal D. Owen Apr 1986

Disease Incidence Of Demersal Finfishes From The Southern And Western Branches Of The Elizabeth River, Virginia, Randal D. Owen

Biological Sciences Theses & Dissertations

Fishes from the industrialized environs of the Elizabeth River, Virginia were surveyed for external evidence of disease during June through October 1984. A highly significant (p < 0.001) incidence of disease was found in demersal fishes collected by otter trawl from a site in the industrially contaminated Southern Branch compared to a less contaminated Western Branch site. Cataracts, fin erosion and dermal lesions were the most commonly occurring anomalies in the Southern Branch finfish.

Static, solid-phase toxicity tests employing sediment collected from the Southern Branch site resulted in an immediate toxic stress in the spot, Leiostomus xanthurus, which resulted in 100% mortality within 24 hours, compared with no mortalities in control systems. Spot exposed to control, i.e., pollution free, and diluted Southern Branch sediments innoculated with the pathogenic bacterial species, Vibrio anguillarium, developed significant (p ≤ 0.020) cases of fin erosion at a mean total bacterial community density …


Deterministic Linear Predictors For Bit Rate Improvement, Dhanvant H. Goradia Apr 1986

Deterministic Linear Predictors For Bit Rate Improvement, Dhanvant H. Goradia

Electrical & Computer Engineering Theses & Dissertations

This thesis addresses the application of deterministic linear predictor s for telemetry based systems. Deterministic linear predictors are considered as a viable alternative to block transform coding in order to achieve bit rate reduction. A method of calculating the predictor coefficients of a deterministic linear predictor is presented. The system model is developed parametrically with respect to the bandwidth, polynomial order, signal class and predictor length. Two classes of signals, deterministic and random are analyzed and bounds on the performance of the deterministic linear predictor are established. A family of six pole Butterworth filters are used as presample filters in …


An Evaluation Of A Taylor-Galerkin Algorithm For High Speed Inviscid Flows Using Quadrilateral And Triangular Elements, Kim S. Bey Apr 1986

An Evaluation Of A Taylor-Galerkin Algorithm For High Speed Inviscid Flows Using Quadrilateral And Triangular Elements, Kim S. Bey

Mechanical & Aerospace Engineering Theses & Dissertations

The Taylor-Galerkin finite element algorithm is used to obtain solutions to the two-dimensional compressible Euler equations. The mathematical formulation of the algorithm is presented for a typical scalar equation. The derivation results in element equations which are assembled over the entire solution domain to obtain the system of equations that are solved explicitly. The algorithm has the unique feature that the finite element matrices can be evaluated in closed form, avoiding expensive numerical integration. Aspects of vector programming strategies and mesh generation important to an effective analysis procedure are also described. Solutions to supersonic flow problems with exact solutions are …


Storm Surge Predictions At Sewell's Point With Local Wind, Pressure, And Previous Surge As Surge Predictors In Chesapeake Bay, Joy Elaine Moses Apr 1986

Storm Surge Predictions At Sewell's Point With Local Wind, Pressure, And Previous Surge As Surge Predictors In Chesapeake Bay, Joy Elaine Moses

OES Theses and Dissertations

The statistical model used to predict storm surge. which is defined as the difference between observed water level and predicted astronomical tide. at Sewell's Point. Virginia. for the last ten years relies on forecast surface air pressures interpolated over a large portion of the Atlantic Ocean. A variation on this method is developed which adds previous station surge and local wind and pressure terms with time leads up to 18 hours to the Pore prediction for surge. and develops surge prediction equations for three substations eight to 65 miles (13 to 105 km) from Sewell's Point. The Sewell's Point surge …


Lineament Analysis In The Richmond Triassic Basin Area Virginia: A Kinematic Model, Richard D. Lutz Apr 1986

Lineament Analysis In The Richmond Triassic Basin Area Virginia: A Kinematic Model, Richard D. Lutz

OES Theses and Dissertations

A lineament study from various sources (color-infrared U-2 photos, rectified drainage maps, and aeromagnetic maps) was conducted to develop a conceptual kinematic model for the Richmond Triassic basin area in Virginia. The lineaments were digitized and subjected to a computerized correlation package that compared the statistically significant peaks within 8 km2 grid cells. Spatially filtered significant 10° contoured trends exhibited a high correlation with mapped structures, outcrop patterns, diabase dikes, and aeromagnetic alignments, suggesting that they represent the surface expressions of the boundaries of subsurface structural domains. Structurally important lineament zones include NE-trending lineaments which segment the basin, NNW-trending …


Relationship Of Stream Drainage And Airphoto-Derived Lineaments To Basement Structures In The North Central Virginia Coastal Plain, William F. Mullen Apr 1986

Relationship Of Stream Drainage And Airphoto-Derived Lineaments To Basement Structures In The North Central Virginia Coastal Plain, William F. Mullen

OES Theses and Dissertations

A lineament study was conducted in the north central coastal plain of Virginia using five different data sources; color infrared photo images, rectified stream segments, bouguer gravity anomaly maps, aeromagnetic anomaly maps, and residual magnetic anomaly maps to determine the potential of aerial photographic analysis in the delineation of basement structural features beneath the sedimentary cover of the Virginia Coastal Plain.

Statistical analysis of 1602 airphoto lineaments and 2337 rectified stream segments produced 15 airphoto lineaments and 18 rectified stream segment lineaments in the north central Coastal Plain Province of Virginia. Azimuthal coincidence of these 33 lineaments determined that there …


On The Existence Of Periodic And Eventually Periodic Solutions Of A Fluid Dynamic Forced Harmonic Oscillator, Charlie H. Cooke Jan 1986

On The Existence Of Periodic And Eventually Periodic Solutions Of A Fluid Dynamic Forced Harmonic Oscillator, Charlie H. Cooke

Mathematics & Statistics Faculty Publications

For certain flow regimes, the nonlinear differential equation Y¨=F(Y)−G, Y≥0, G>0 and constant, models qualitatively the behaviour of a forced, fluid dynamic, harmonic oscillator which has been a popular department store attraction. The device consists of a ball oscillating suspended in the vertical jet from a household fan. From the postulated form of the model, we determine sets of attraction and exploit symmetry properties of the system to show that all solutions are either initially periodic, with the ball never striking the fan, or else eventually approach a periodic limit cycle, after a sufficient number of bounces away from …


Late Prehistoric And Protohistoric Large Mammal Zoogeography Of Virginia, Robert K. Rose Jan 1986

Late Prehistoric And Protohistoric Large Mammal Zoogeography Of Virginia, Robert K. Rose

Biological Sciences Faculty Publications

Evidence derived from18late prehistoric (middle and late Woodland Period) archeological sites, from several early historical accounts, and from the current understanding of the distribution of Virginia mammals indicates that the large mammal fauna of the Commonwealth has not changed substantially within the past 4,000 yrs. Some species (e.g., bison, elk, timber wolf, and mountain lion) have been extirpated since the settlement of Virginia by Europeans; some previously extirpated species (e.g., porcupine, coyote, and beaver) have been naturally or artificially reintroduced during the historical period, and others (e.g., woodchuck and red fox) probably have expanded their distributions as a result of …


The Physics Of The Antarctic Circumpolar Current, Worth D. Nowlin, John M. Klinck Jan 1986

The Physics Of The Antarctic Circumpolar Current, Worth D. Nowlin, John M. Klinck

CCPO Publications

A region of transition of surface water characteristics from subantarctic to Antarctic and an associated eastward flowing Antarctic Circumpolar Current (ACC) have long been recognized to exist as a band around Antarctica. In this review we summarize the most important observational and theoretical findings of the past decade regarding the ACC, identify gaps in our knowledge, and recommend studies to address these. The nature of the meridional zonation of the ACC is only now being revealed. The ACC seems to exist as multiple narrow jets imbedded in, or associated with, density fronts (the Subantarctic and Polar fronts) which appear to …


Wind-Driven Upwelling In The Vicinity Of Cape Finisterre, Spain, Charles R. Mcclain, Shenn-Yu Chao, Larry P. Atkinson, Jack O. Blanton, Frederico De Castillejo Jan 1986

Wind-Driven Upwelling In The Vicinity Of Cape Finisterre, Spain, Charles R. Mcclain, Shenn-Yu Chao, Larry P. Atkinson, Jack O. Blanton, Frederico De Castillejo

CCPO Publications

Observations and numerical simulations of upwelling along the Galician coast of Spain during April 1982 are presented. In situ measurements include shipboard determinations of hydrographic and biological parameters from a grid of stations covering the continental shelf from Cape Finisterre to Ria de Vigo, sea level data from Vigo and La Coruña, and wind stress estimates derived from the ship winds and from surface pressure charts. Sea surface temperature information and pigment concentration information have been obtained from a sequence of satellite images from the NOAA 7 advanced very high resolution radiometer and the Nimbus 7 coastal zone color scanner, …


Deep Flow Variability In Central Drake Passage, John M. Klinck, Eileen E. Hofmann Jan 1986

Deep Flow Variability In Central Drake Passage, John M. Klinck, Eileen E. Hofmann

CCPO Publications

A rotary empirical orthogonal function analysis of the currents measured in central Drake Passage during DRAKE 79 shows that the deep (2500 m) flow has the same spatial and temporal structure as the flow at 500 m, suggesting that current variability in this region penetrates to the bottom. However, comparison of the time amplitude of the corresponding modes indicates that the variability of the 2500 m flow resulting from north to south shifts in the location of the Polar Front lags that at 500 m by one to three days. This implies that the Polar Front slopes to the east …


Nonadiabatic Theory Of Fine-Structure Branching Cross Sections For Na-He, Na-Ne, And Na-Ar Optical Collisions, Linda L. Vahala, P. S. Julienne, Mark D. Havey Jan 1986

Nonadiabatic Theory Of Fine-Structure Branching Cross Sections For Na-He, Na-Ne, And Na-Ar Optical Collisions, Linda L. Vahala, P. S. Julienne, Mark D. Havey

Electrical & Computer Engineering Faculty Publications

The nonadiabatic close-coupled theory of atomic collisions in a radiation field is generalized to include electron spin and is used to consider the weak-field Na–rare-gas (RG) optical collision Na(2S1/2)+RG+nhν μNa(2Pj)+RG+(n-1)hν. The effects of detuning and incident energy on the branching into the atomic Na 3p2P3/2 and 3p2P1/2 states are examined. The cross sections σ(j) are found to have a strong asymmetry between red and blue detuning as well as a complex threshold and resonance structure dependence on energy. A partial cross-section analysis …


Factors Regulating Settlement And Microhabitat Use By Spiny Lobsters Panulirus Argus, William F. Herrnkind, Mark J. Butler Iv Jan 1986

Factors Regulating Settlement And Microhabitat Use By Spiny Lobsters Panulirus Argus, William F. Herrnkind, Mark J. Butler Iv

Biological Sciences Faculty Publications

Clumps of highly-branched red algae Laurencia spp. serve as important settling habitat for postlarval spiny lobsters Panulirus argus and as residence for early benthic-stage juveniles. Given choice between the 2 most abundant macrophytes in Florida Bay, Laurencia spp. and the seagrass Thalassia testudinum, postlarval and juvenile lobsters chose Laurencia spp. Postlarvae apparently use intricate algal architecture as a cue for settlement, whereas juveniles use both architecture and food abundance in selecting habitat. In tethering experiments, predation on juvenile lobsters was very high on open sand, much reduced in algal clumps and seagrass, and lowest in dense algal meadows. Predation …


Tidal Circulation In Chesapeake Bay, Carl W. Fisher Jan 1986

Tidal Circulation In Chesapeake Bay, Carl W. Fisher

OES Theses and Dissertations

This study is a comprehensive examination of the tidal circulation of Chesapeake Bay and its major tributaries. Tide and current data, which were observed in Chesapeake Bay by the National Ocean Service during the period from 1972 to 1983, are analyzed and used to construct charts that describe the tide and tidal current. Frictionally damped analytic models are used to: explain the tidal hydrodynamics of the observed tides, determine the location of the quasinodes and antinodes of the M2 and K1 tidal waves, explain the relationship of the tides and tidal currents, and determine if the tide in …


Estimation In Truncated Exponential Family Of Distributions, Laxman M. Hegde Jan 1986

Estimation In Truncated Exponential Family Of Distributions, Laxman M. Hegde

Mathematics & Statistics Theses & Dissertations

Estimating the parameters of a truncated distribution is a well known problem in statistical inference. The non-existence of the maximum likelihood estimator (m.l.e.) with positive probability in certain truncated distributions is not well known. To mention a few results in the literature:

(i) Deemer and Votaw 1955 show that the maximum likelihood estimator does not exist in a truncated negative exponential distribution on 0,T , T > 0 known, whenever the sample mean x (GREATERTHEQ) T/2.

(ii) Broeder 1955 shows that the maximum likelihood estimator of the scale parameter of a truncated gamma distribution, with the shape parameter being known, becomes …


On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi Jan 1986

On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi

OES Faculty Publications

Summary. The statistical capability of the mb :Ms, discriminant for the discrimination of earthquake and explosion populations is examined by application of discriminant functions to a group of 83 explosions and 72 earthquakes in Eurasia. Equations are derived for the probability that an event is an earthquake or an explosion. The positive sign of DIS in the decision index equation,

DIS, = 34.3383 - 11.9569 mbi, + 7.1 161 Msi,

indicates that the event i is an earthquake. Its negative sign indicates that event i is an explosion. The probability of …


Sediment Processing And Selective Feeding By Pectinaria Koreni (Polychaeta: Pectinariidae), Fred C. Dobbs, Teresa A. Scholly Jan 1986

Sediment Processing And Selective Feeding By Pectinaria Koreni (Polychaeta: Pectinariidae), Fred C. Dobbs, Teresa A. Scholly

OES Faculty Publications

Pectinaria (Lagis) koreni (Malmgren) is an abundant, deposit-feeding, infaunal inhabitant of shallow-water marine environments in northern Europe. Laboratory experiments were performed to quantify the polychaete's sediment processing in 2 distinct sediments, 1 fine-grained and high in combustibles, the other coarse-grained and low in combustibles. Gut passage time and time to pseudodefecation were predictable only in coarse-grained sediment. In both sediments, reworking rate increased with worm size and over time, although temporal patterns differed in the 2 sediments. The ratio of pseudodefecated sediment to defecated sediment did not differ significantly over time in either sediment, but the ratio was greater in …


In Situ Growth And Chemical Composition Of The Giant Kelp, Macrocystis Pyrifera: Response To Temporal Changes In Ambient Nutrient Availability, Richard C. Zimmerman, James N. Kremer Jan 1986

In Situ Growth And Chemical Composition Of The Giant Kelp, Macrocystis Pyrifera: Response To Temporal Changes In Ambient Nutrient Availability, Richard C. Zimmerman, James N. Kremer

OES Faculty Publications

Temporal variations in growth of the giant kelp Macrocystis pyrifera were examined in relation to ambient nutrient availability and chemical composition of mature blades, the primary site of nutrient and carbohydrate storage in M. pyrifera. The effect of nutrient availability on growth was well approximated by a Monod rectangular hyperbola, with growth saturating at ambient nitrate concentra- tions between 1 and 2 FM. M. pyrlfera was unable to generate nutrient reserves that would last beyond 30 d. Nitrogen reserves were stored as free amino acids, and generally constituted about 10 % of total tissue nitrogen. Total nitrogen content was …


Absorption Cross-Sections Of Sodium Diatomic Molecules, Zeng-Shevan Fong Dec 1985

Absorption Cross-Sections Of Sodium Diatomic Molecules, Zeng-Shevan Fong

Physics Theses & Dissertations

The absorption cross sections of sodium dimers were studied using a heat pipe over operating in the non-heat-pipe mode. Three wavelength regions were observed. They are in the red, the green-blue, and the near ultraviolet regions. The absorption cross section depends on the wavelength of the incident light. Representative peak values for the v"=0 progression in the red and green-blue regions are 2.59 A sup 2 (average value) and 11.77 A sup 2 (Tave=624 K). The value for the C greater than X transitions is several tenths A sup 2. The cross sections were measured from absorption spectra …


Lineament Analysis And Tectonic Interpretation For The Central Tharsis Region, Mars, Robert C. Anderson Oct 1985

Lineament Analysis And Tectonic Interpretation For The Central Tharsis Region, Mars, Robert C. Anderson

OES Theses and Dissertations

Lineament studies conducted for the Central Tharsis Region of Mars (JOON and JOOS latitude; 450w to 157.50W longitude) indicate two major events controlled the formation of the Tharsis Dome: 1) a pre-Tharsis fracture system consisting of North-West (3150) trending fractures; and 2) a Tharsian fracture system containing North-South (355°) and East-West (275°) trending fractures. The North-West (3150) trending fractures represent a crustal weakness zone which controlled the early formation of the Tharsis Dome. Analytical studies suggest four centers of uplift: 1) 6°N, 124°W; 2) 0.5°N, 114°W; 3) 5°S, 105°W; and 4) 7°S, 104°W. Each of these uplifting centers is associated …


Comparison Of An Improved Plankton Sampler To The Standard Conical Plankton Net, Ronald S. Schmidt Oct 1985

Comparison Of An Improved Plankton Sampler To The Standard Conical Plankton Net, Ronald S. Schmidt

OES Theses and Dissertations

A comparison of field and tank tests between the standard conical plankton net and an improved version of a plankton sampler is presented. The improved sampler was shown to filter larger quantities of water than the standard net without having the filtration efficiency reduced below 85%. The improved sampler was also shown to capture an increased number of plankton per volume sampled, as a result of eliminating increased avoidance activity by zooplankton. It was not shown that. the improved sampler capture either larger maximum sizes of zooplankton or additional species.


Conodont Biostratigraphy Of The Cambrian-Ordovician Boundary Interval In The Northern Shenandoah Valley Of Virginia, U.S.A., Randall C. Orndorff Oct 1985

Conodont Biostratigraphy Of The Cambrian-Ordovician Boundary Interval In The Northern Shenandoah Valley Of Virginia, U.S.A., Randall C. Orndorff

OES Theses and Dissertations

Conodonts collected from two measured sections in the northern Shenandoah Valley of Virginia indicate that locally the Cambrian-Ordovician boundary is within the upper part of the Conococheague Formation and that the Conococheague-Stonehenge formational contact as defined in this study, is diachronous in relation to the boundary. Using the generally accepted definition of the CambrianOrdovician boundary as at the base of the trilobite Missisguoia Zone or within the conodont Hirsutodontus hirsutus Subzone of the Cordylodus proavus Zone, it is found here that the boundary is 230 ft (70 m) below the formational contact at the Narrow Passage Creek section. Several North …


Design Of Multivariable Feedback Control Systems Via Spectral Assignment, Mohsen Marefat Oct 1985

Design Of Multivariable Feedback Control Systems Via Spectral Assignment, Mohsen Marefat

Electrical & Computer Engineering Theses & Dissertations

During the past 15 year s significant advances have been made towards developing viable synthesis- techniques for multivariable feedback control systems. The entire aggregate of this theoretical work has been reviewed and consolidated. Diverse notations have been standardized into a single system. A two-step design philosophy for spectral assignment has been developed which first meets stability and time response requirements by assigning eigenvalues and eigenvector s and then provides for attainment of secondary objectives without significant deviation from the initial assignment. Finally, a computer-aided design package has been created to streamline the process of mathematical calculation and to allow users …