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1993

Theses/Dissertations

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Articles 1 - 30 of 41

Full-Text Articles in Physics

Photoluminescence Study Of Gallium Arsenide, Aluminum Gallium Arsenide, And Gallium Antimonide Thin Films Grown By Metalorganic Chemical Vapor Deposition, John Mark Koons Dec 1993

Photoluminescence Study Of Gallium Arsenide, Aluminum Gallium Arsenide, And Gallium Antimonide Thin Films Grown By Metalorganic Chemical Vapor Deposition, John Mark Koons

Theses

The photoluminescence produced by four MOCVD grown epitaxial thin film samples was studied to give insight into sample quality. The four samples under this study were GaAs on a GaAs substrate, Al.25Ga.75As on a GaAs substrate, Al.30Ga.7OAs on a GaAs substrate, and GaSb on a GaSb substrate. Excitation was achieved through the use of the 514.0 nm line of an argon ion laser, and sample cooling was attained by use of a cryostat cooler using helium gas to attain a low temperature limit of 10°K. The GaAs and Al.30 ...


Modeling Of The Surface Plasmon Resonance (Spr) Effect For A Metal-Semiconductor (M-S) Junction At Elevated Temperatures, Erik De Jesus Sanchez Nov 1993

Modeling Of The Surface Plasmon Resonance (Spr) Effect For A Metal-Semiconductor (M-S) Junction At Elevated Temperatures, Erik De Jesus Sanchez

Dissertations and Theses

The effect of temperature increase on the optical excitation of Surface Plasmon Resonance (SPR) at an Ag-Si metal-semiconductor (M-S) junction at a wavelength of 1 . 1 52 pm is investigated theoretically using computer modeling in Fortran. In order to accurately quantify the SPR, the temperature dependent optical constants for Ag and Si are obtained theoretically or semiempirically , using a Drude model for Ag and previous experimentally determined equations for Si (the behavior of the optical constants for crystalline Si and doped Si are found to have very little deviation between each other for our case). An improvement in the theoretical ...


Size Imperfections In One-Dimensional Periodic Optical Arrays, Yan Zhong Aug 1993

Size Imperfections In One-Dimensional Periodic Optical Arrays, Yan Zhong

Master's Theses

The concepts of band theory for electrons can also be employed to describe the behavior of electromagnetic waves propagating in periodic dielectric structures. These periodic structures can produce photonic band gaps in which the propagation of electromagnetic waves is strictly prohibited. The introduction of impurities in such system gives rise to donor and acceptor gap modes in electron system and to energy gap modes in photonic system.

In my thesis, the impurity modes in one-dimensional, periodic, dielectric system will be studied. These modes are introduced in the 1-d dielectric structure by altering the thickness of one slab in an otherwise ...


Comparison Of Ion Adsorption To Phophatidylcholine/Phosphatidylserine And Sarcoplasmic Reticulum Membranes, Martin Mense Jul 1993

Comparison Of Ion Adsorption To Phophatidylcholine/Phosphatidylserine And Sarcoplasmic Reticulum Membranes, Martin Mense

Dissertations and Theses

Artificial lipid membranes have been used in biophysical studies as well defined models of biological membranes. In the present work we studied adsorption of ions to artificial lipid membranes, composed of phosphatidylcholine (PC) and phosphatidylserine (PS), and to biological membrane from sarcoplasmic reticulum (SR). The studies of ion adsorption and electrokinetic characterization of membranes were done by means of microelectrophoresis of PC/PS liposomes and SR vesicles. The ions of interest were positively charged potassium (K), calcium (Ca), tetraphenylarsonium (TPAs), tetraphenylphosphonium (TPP) and negatively charged pentachlorophenol (PCP). Electrophoretic mobility of PC/PS liposomes and SR vesicles has been measured as ...


A Retarding-Potential Analyzer For Measuring Energy Distributions In Electron Beams, Li Zhou Jul 1993

A Retarding-Potential Analyzer For Measuring Energy Distributions In Electron Beams, Li Zhou

Dissertations and Theses

An energy analyzer for electron beams, based on a retarding-potential method, has been studied both experimentally and theoretically. In this method a potential energy barrier at right-angles to the beam acts as a high-pass energy filter allowing electrons having energies greater than the barrier height to pass through while turning back electrons of lower energy. The potential barrier in the present study was created by applying a negative potential to an electrode consisting of a 600/inch hexagonal copper mesh or an electrode having a pair of single apertures in series (compound aperture). Two different compound apertures, of diameters 0 ...


Design And Construction Of A Lithium Vapor Oven, Corey A. Leon Jul 1993

Design And Construction Of A Lithium Vapor Oven, Corey A. Leon

Honors Theses

A lithium vapor oven to be used as a source of lithium target atoms in atomic collision experiments was designed and constructed. The oven was installed in the beamline of the Van de Graaff accelerator at Western Michigan University. Test results indicated the oven produced a diffuse cloud of evaporated lithium instead of the intended concentrated jet spray. Recommendations concerning the design are made for future efforts.


Enhanced Retroreflection Of Light From Rough Metal Surfaces, Sivakumar Natarajan Jun 1993

Enhanced Retroreflection Of Light From Rough Metal Surfaces, Sivakumar Natarajan

Master's Theses

The optical constants n and k measured by Johnson and Christy (1972) for the noble metals (gold, silver and copper) are used to analyze the relationship between the surface characteristics and the peak height and half-width of the backscattering peak which is observed in the angular distribution of the intensity of diffusely reflected light at a vacuum-metal interface in a direction antiparallel to the original incident beam. Surfaces with surface roughness of heights less than 200 A to 300 A will be considered and a recently developed perturbation treatment will be used in these studies.

The backscattering of light from ...


Properties Of Rigid Foams For Application As Materials For Light Weight Structures In Space, Huichen Chi May 1993

Properties Of Rigid Foams For Application As Materials For Light Weight Structures In Space, Huichen Chi

All Graduate Theses and Dissertations

The mechanical and mesoscopic structural properties of rigid cellular foam made of polystyrene have been investigated. Basic properties (e.g., density, total and available porosity, permeability, surface area, isotropicity, and cell size and cell wall thickness distributions) were measured. In most cases, alternative methods were used to determine which methods were most appropriate for the type of samples we studied. Standard compression and deflection mechanical tests were performed. The stress-strain curves and related mechanical properties were found to agree with standard cellular structural models of open-cell foams.

We investigated the effects of small (~<5 atm) hydrostatic stress applied to foam samples for long periods of time (~one day). We observed large changes (up to a factor of three) in the stress-strain diagrams, Young's modulus, elastic collapse stress, ultimate strength, resilience, Poisson's ratio, permeability, penetration depth, and available porosity. Effects were most pronounced above 2 atm applied pressure differential, but were observed even for 1 atm loads. Short-term exposure to loads up to ten times as large did not cause comparable changes. These changes were interpreted as resulting from observed changes in the mesoscopic structure occurring near the surface using standard cellular structural models.

This work was originally motivated by applications ...


Non-Resonant Transfer And Excitation For S^13+ Projectiles Colliding With Neutral Gas Targets, Liang Duo Apr 1993

Non-Resonant Transfer And Excitation For S^13+ Projectiles Colliding With Neutral Gas Targets, Liang Duo

Master's Theses

Non-resonant Transfer and Excitation (NTE) by 20-70 Mev S,3+ projectiles in collisions with neutral gas targets of He, Ne and Ar is investigated. For NTE, positively charged projectiles undergo excitation and electron capture in a single collision in which the capture and excitation processes are independent events. The mechanisms involved in the NTE process are electron-nucleus interactions, and the combination of projectile excitation and capture is a two-step process. In this work, NTE cross sections, along with total K x-ray production cross sections and total single-electron capture and loss cross sections, were measured as a function of projectile energy ...


Impurity Modes In Photonic Band Structures, Yi-Fen Chang Apr 1993

Impurity Modes In Photonic Band Structures, Yi-Fen Chang

Master's Theses

In this thesis I study a theoretical model of one-dimensional dielectric array (a layered system of dielectric slabs) which forms a periodic dielectric system in which band gaps are opened in the frequency spectrum. Specifically, we study such a one-dimensional array with linear impurities introduced in the periodic dielectric system. In these impurity structures narrow resonant modes are found in the band gaps as impurity modes and these impurity modes change with the dielectric constant. This impurity problem is similar to the donor and acceptor state problem in electronic semiconductors. The calculations presented in this thesis are based on numerically ...


The Effects Of Electron Radiation On The Glass Transition Temperature Of A Polyetherimide, Kristen Tulloch Kern Apr 1993

The Effects Of Electron Radiation On The Glass Transition Temperature Of A Polyetherimide, Kristen Tulloch Kern

Physics Theses & Dissertations

The effects of electron radiation on a polyetherimide (PEI), Ultem*, were investigated. In particular, the changes in the glass transition temperature (Tg) with absorbed radiation dose were studied. The polymer was exposed to mono-energetic beams of 100-keV electrons and 1.0-MeV electrons for doses up to 100 megagray (MGy). Dosimetry for the exposures was based on Monte-Carlo simulations of the transfer of energy from an energetic electron to the polymer and on comparison to Nylon standards. Dynamic mechanical analysis was used to determine the (Tg) for non-exposed PEI and the changes in (Tg) resulting from irradiation. The ...


A Measurement Of The [Tau Lepton] Polarization At The Z Resonance With The Delphi Detector At Lep , Antonio Wong Chan Jan 1993

A Measurement Of The [Tau Lepton] Polarization At The Z Resonance With The Delphi Detector At Lep , Antonio Wong Chan

Retrospective Theses and Dissertations

The polarization of [tau] leptons produced in the reaction e[superscript]+e[superscript]-→[tau][superscript]+[tau][superscript]- near the peak of the Z° resonance has been measured using a sample of 24904 [tau][superscript]+[tau][superscript]- events, with an estimated background of 1.5%. We have selected 4562 [tau]→ e[nu][macron][nu], 2218 [tau]→[pi][nu] and 5133 [tau]→[rho][nu] candidates. The mean value obtained is P[subscript][tau]=-0.176± 0.029. This corresponds to a ratio of the neutral current vector to the axial-vector coupling constants of the [tau] lepton of g[subscript]spV[tau]/g ...


Support Minimized Inversion Of Acoustic And Elastic Wave Scattering , Ali Safaeinili Jan 1993

Support Minimized Inversion Of Acoustic And Elastic Wave Scattering , Ali Safaeinili

Retrospective Theses and Dissertations

Inversion of limited data is common in many areas of NDE such as X-ray Computed Tomography (CT), Ultrasonic and eddy current flaw characterization and imaging;In many applications, it is common to have a bias toward a solution with minimum (L[superscript]2)[superscript]2 norm without any physical justification. When it is a priori known that objects are compact as, say, with cracks and voids, by choosing "Minimum Support" functional instead of the minimum (L[superscript]2)[superscript]2 norm, an image can be obtained that is equally in agreement with the available data, while it is more consistent ...


Vibrational And Acoustic Response Of Ribbed Plates , Ten-Bin Juang Jan 1993

Vibrational And Acoustic Response Of Ribbed Plates , Ten-Bin Juang

Retrospective Theses and Dissertations

A self-consistent mathematical formulation, using the Fourier transform method and a direct Gaussian numerical integration scheme, is developed and verified for analysis of both vibrational and acoustic responses of infinite submerged ribbed plates. Further steps developed from standard theories make structural intensity, acoustic intensity, and acoustic power calculations possible in the nearfield and farfield, and are demonstrated in this work;The direct numerical integration scheme adopted to obtain responses has proved to be straightforward and reliable. Although the double integration expression in some responses makes the technique infeasible, a practical way to overcome that difficulty is demonstrated using a standard ...


Frequency Conversion Analysis Of Noise In Heterojunction Bipolar Transistor Oscillators Including Periodically Modulated Noise Sources , Bradley Allen Kramer Jan 1993

Frequency Conversion Analysis Of Noise In Heterojunction Bipolar Transistor Oscillators Including Periodically Modulated Noise Sources , Bradley Allen Kramer

Retrospective Theses and Dissertations

A procedure which may be used to analyze the noise characteristics of HBT oscillators is presented. A large signal model of a HBT is developed based largely on the Gummel-Poon transistor model. A new base-emitter diffusion capacitance model is also generated which shows improved accuracy over conventional bipolar transistor models in characterizing HBTs. The large signal characteristics of the oscillator are then established using a time domain simulator. Conversion matrix theory is applied to the large signal model to generate an equivalent linear oscillator model which accounts for all of the frequency conversion effects which occur due to circuit nonlinearities ...


Synthesis, Characterization, Phase Diagrams And Superconducting And Normal State Magnetic Properties Of La[Subscript 2-X]Sr[Subscript X]Cuo4 (0 [Less Than Or Equal To] X [Less Than Or Equal To] 0.08) And Electrochemically Oxidized La[Subscript 2-X]Sr[Subscript X]Cuo[Subscript 4 + Delta] (0 [Less Than Or Equal To] X [Less Than Or Equal To] 0.33, 0 [Less Than Or Equal To Delta Less Than Or Equal To] 0.12) , Fangcheng Chou Jan 1993

Synthesis, Characterization, Phase Diagrams And Superconducting And Normal State Magnetic Properties Of La[Subscript 2-X]Sr[Subscript X]Cuo4 (0 [Less Than Or Equal To] X [Less Than Or Equal To] 0.08) And Electrochemically Oxidized La[Subscript 2-X]Sr[Subscript X]Cuo[Subscript 4 + Delta] (0 [Less Than Or Equal To] X [Less Than Or Equal To] 0.33, 0 [Less Than Or Equal To Delta Less Than Or Equal To] 0.12) , Fangcheng Chou

Retrospective Theses and Dissertations

La[subscript] 2-xSr[subscript] xCuO[subscript]4 (0 ≤ x ≤ 0.15) can all be intercalated with oxygen by an novel electrochemical oxidation method. Bulk superconductivity is found with an onset T[subscript] c ≈ 40 K for the whole range 0.01 ≤ x ≤ 0.15; for x = 0.25 and 0.33, the electrochemical oxidation did not improve the superconducting properties. The magnetic susceptibility [chi](T = 50-320 K) data for La[subscript]2CuO[subscript]4.11 and La[subscript]1.92Sr[subscript]0.08CuO[subscript]4.07 are nearly identical with those of conventionally prepared La[subscript]1.85Sr[subscript]0 ...


Theoretical Study Of The Noble Metals On Semiconductor Surfaces And Ti-Base Shape Memory Alloys , Yungui Ding Jan 1993

Theoretical Study Of The Noble Metals On Semiconductor Surfaces And Ti-Base Shape Memory Alloys , Yungui Ding

Retrospective Theses and Dissertations

The electronic and structural properties of the (√3 x √3) R30° Ag/Si(111) and (√3 x √3) R30° Au/Si(111) surfaces are investigated using first principles total energy calculations. We have tested almost all experimentally proposed structural models for both surfaces and found the energetically most favorable model for each of them. The lowest energy model structure of the (√3 x √3) R30° Ag/Si(111) surface consists of a top layer of Ag atoms arranged as "honeycomb-chained-trimers" lying above a distorted "missing top layer" Si(111) substrate. The coverage of Ag is 1 monolayer (ML). We find ...


Acoustically Driven Integrated Microstrip Antennas And Electromagnetic Radiation From Piezoelectric Devices , Charles Forrest Campbell Jan 1993

Acoustically Driven Integrated Microstrip Antennas And Electromagnetic Radiation From Piezoelectric Devices , Charles Forrest Campbell

Retrospective Theses and Dissertations

For a receiver system to be considered integrated, the antenna and electronics need to be fabricated on a single semiconductor wafer. To avoid EMI problems, the circuitry must somehow be shielded from the environment where the antenna resides. The required shielding may be accomplished by separating the antenna on one side of the wafer from the electronics on the other side with a conducting ground plane. Energy may be acoustically coupled from the antenna to the circuitry through the ground plane via thin film piezoelectric transducers on either side of the wafer. The radiating side of the wafer would then ...


A Study Of The Guiding Center Approximation, Qun Yao Jan 1993

A Study Of The Guiding Center Approximation, Qun Yao

Dissertations, Theses, and Masters Projects

A Hamiltonian treatment for the motion of a charged particle in a toroidal magnetic field is given. Assuming the plasma equilibrium, Boozer coordinates are used. The Hamiltonian of the exact trajectory is given in the guiding center coordinates. The higher order corrections to the standard drift Hamiltonian are derived. It is shown that the exact Hamiltonian depends on both the field strength and the shape of the magnetic surfaces (the metric of Boozer coordinates) while the standard drift Hamiltonian depends only on the field strength. The first order correction to the standard drift Hamiltonian, in gyroradius to system size, depends ...


A Measurement Of The Branching Ratio Of Long-Lived Neutral Kaon Going To Positive Muon Negative Muon, Michael Thomas Witkowski Jan 1993

A Measurement Of The Branching Ratio Of Long-Lived Neutral Kaon Going To Positive Muon Negative Muon, Michael Thomas Witkowski

Dissertations, Theses, and Masters Projects

The branching ratio $B(K\sbsp{L}{0} \to \mu\sp+\mu\sp-)$ has been measured using data obtained during running periods in 1988, 1989 and 1990. The data obtained in the 1990 running period are the latest and last from BNL experiment E791. During the three running periods, 87, 274 and 346 respective candidate events were observed, forming an overall sample of 707 $\mu\sp+\mu\sp-$ events. This number represents the largest sample to-date of $K\sbsp{L}{0} \to \mu\sp+\mu\sp-$ events. The result for the branching fraction using the total data set is $B ...


The Effects Of Granularity On The Microwave Surface Impedance Of High Kappa Superconductors, Stephen Keith Remillard Jan 1993

The Effects Of Granularity On The Microwave Surface Impedance Of High Kappa Superconductors, Stephen Keith Remillard

Dissertations, Theses, and Masters Projects

The microwave surface impedance of granular high temperature superconductors is an important figure of merit for technological applications. Because the behavior of the granular materials deviates significantly from that of the ideal defect free superconductors, the loss mechanisms are not fully understood. This dissertation seeks to quantify the contribution of granularity to centimeter wave and millimeter wave losses. By understanding these losses, the superconductive coupling between neighboring grains can also be understood.;The weakly coupled grain model is used as a phenomenological description of the microwave surface impedance. The granular superconducting surface is modelled as an effective resistively shunted Josephson ...


Beyond The Standard Model: New Scalars And New Leptons, Yao Yuan Jan 1993

Beyond The Standard Model: New Scalars And New Leptons, Yao Yuan

Dissertations, Theses, and Masters Projects

Physics that might lie beyond the standard model is discussed, with special emphasis on two possible extensions of the standard model: multi-Higgs extension, and the fourth generation leptons.;In multi-Higgs-boson extensions of the standard model, tree-level flavor-changing neutral currents exist naturally. It is often believed that the presence of the tree-level FCNC in this model is fatal, unless a discrete symmetry is added, since it requires the exchanged scalar to be extremely heavy. This follows, however, from the assumption that the flavor-changing coupling is quite large. Using a more natural value for the flavor-changing coupling, much smaller bounds were obtained ...


A Study Of Molecular Order And Motion In Nematic Liquid Crystal Mixtures, Jon Michael Goetz Jan 1993

A Study Of Molecular Order And Motion In Nematic Liquid Crystal Mixtures, Jon Michael Goetz

Dissertations, Theses, and Masters Projects

Materials which flow like fluids, but possess anisotropic properties like molecular crystals, are called 'liquid crystals'. Studies of liquid crystals contribute to our understanding of how molecular orientation influences macroscopic properties. This thesis presents experimental and theoretical investigations of molecular order and dynamics in nematic liquid crystal systems. First, deuterium nuclear magnetic resonance is used to determine the degree of orientational order of both components of a liquid crystal mixture simultaneously. The temperature dependence of the four order parameters is interpreted using a newly developed mean field theory of nematic binary mixtures composed of biaxial molecules. Next, mean field theory ...


Photoabsorption Spectra Of Hydrogen In Magnetic Fields, John A. Shaw Jan 1993

Photoabsorption Spectra Of Hydrogen In Magnetic Fields, John A. Shaw

Dissertations, Theses, and Masters Projects

Measurements of the absorption spectrum of atomic H in strong magnetic fields have been analyzed. The measurements, performed by the Bielefeld, Germany experimental group, investigated the photoabsorption to levels near the ionization threshold in magnetic fields ranging from 2.7 to 6 Tesla. Taking advantage of a classical scaling law, the photon energy and the magnetic field strength were varied simultaneously in the experiment and the absorption rate vs. B{dollar}\sp{lcub}-1/3{rcub}{dollar} at fixed scaled-energy, {dollar}\varepsilon{dollar} = E/(B/B{dollar}\sb{lcub}\rm o{rcub})\sp{lcub}2/3{rcub}{dollar} was measured ...


Relativistic Two-Body Wave Equations , Alan James Sommerer Jan 1993

Relativistic Two-Body Wave Equations , Alan James Sommerer

Retrospective Theses and Dissertations

The history and conceptual development of relativistic two-body formalisms leading up to the Bethe-Salpeter equation are reviewed. The various three dimensional reductions of the Bethe-Salpeter equation, in particular the quasipotential equations, and methods for solving them are discussed. Previous studies which attempted to assess the relative merits of the various equations are examined, and a new criterion for judging the equations is proposed. The bound state energy predictions of the traditional quasipotential equations are compared with the predictions of fourth order perturbation theory at small coupling. The equations are ranked according to how well they reproduce perturbation theory at low ...


An Axial Approach To Detection In Capillary Electrophoresis , John Aaron Taylor Jan 1993

An Axial Approach To Detection In Capillary Electrophoresis , John Aaron Taylor

Retrospective Theses and Dissertations

The purpose of this research has been to develop and demonstrate visualization schemes which further the capabilities of capillary electrophoresis instrumentation. Our approach involves on-axis illumination of the compounds inside the capillary detection region and is applied to absorbance and fluorescence detection;Absorbance measurements were accomplished by focussing an incident beam of laser light into one end of the separation capillary. By utilizing signals collected over the entire length of the analyte band, this technique enhances the analytical path length of conventional absorbance detection sixty fold. The demonstrated instrument offers a fifteen-fold improvement in concentration limits of detection;Three fluorescence ...


Effects Of Randomly Rough Surfaces On Ultrasonic Inspection , Mehmet Bilgen Jan 1993

Effects Of Randomly Rough Surfaces On Ultrasonic Inspection , Mehmet Bilgen

Retrospective Theses and Dissertations

Surface finish of an industrial part affects its ultrasonic inspection and consequently the surfaces are often machined smooth before the evaluation. Ultrasonic inspection through smooth surfaces has been well studied and understood. A theoretical basis has been established for the characterization of interior cracks, voids and inclusions, and vast amount of literature exists. However, much less is known about quantitative ultrasonic inspection of such flaws in parts with rough surfaces, e.g. machine marks or "as-cast" surfaces. A question arises "When can an industrial part with randomly rough surfaces be inspected robustly using ultrasound?" This dissertation is aimed at answering ...


Topics In Electroweak Baryogenesis: The Sphaleron And T-Violation , Seungkoog Lee Jan 1993

Topics In Electroweak Baryogenesis: The Sphaleron And T-Violation , Seungkoog Lee

Retrospective Theses and Dissertations

Assuming that beyond the standard model physics can be parametrized in terms of high dimensional operators, we examine their effects on the energy of the sphaleron and the classical solution of the gauge and Higgs fields. In the absence of fermions, all of the six dimension 6 operators which are SU(2) symmetric have a small effect when calculated perturbatively. However, calculated non-perturbatively, one of the operators alters the boundary conditions of the equations of motion of the Higgs and gauge fields involved, and another operator gives rise to an abrupt change in the sphaleron energy at a small but ...


Long Chain Molecules In The Molten State: Surface Adsorption, Near Surface Structure, And Mutual-Diffusion, Xiaofeng Zhao Jan 1993

Long Chain Molecules In The Molten State: Surface Adsorption, Near Surface Structure, And Mutual-Diffusion, Xiaofeng Zhao

All Dissertations, Theses, and Capstone Projects

The surface segregation in a binary mixture of polymer due to surface energy difference or end-grafting is studied. The surface energy difference induced segregation is compared with the mean-field theory. The end-labeling of chains strengthens the ability of the chain to bind to the surface, and the stretching of the end grafted chains is proved to be a controlling fact limiting the brush density. The structure of a chain near a surface needs to be known in order to make more quantitative analysis. Such knowledge is currently not available although a reflecting surface model is proposed.

We also studied the ...


An Experimental Method For Structural Intensity And Source Location , Yong Zhang Jan 1993

An Experimental Method For Structural Intensity And Source Location , Yong Zhang

Retrospective Theses and Dissertations

This study investigates the structural intensity and the force distribution function as tools to study vibrating plates. A laser Doppler vibrometer is used in measuring the plate normal velocity for the calculation of the structural intensity and the force distribution function. Several examples show the possibility of locating sources and studying the influence of ribs and damping material attached to the plate surface;There have been many studies on structural intensity. This thesis shows that the differences between two commonly used formulations are the assumptions that are used in deriving the formulas;The force distribution function is introduced in this ...