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Electromagnetic Modes Of An Inhomogeneous Sphere, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

In many cases the electromagnetic modes of a sphere can be obtained exactly. Special simplifications occur when the conductivity, complex permittivity, and complex permeability vary only in the radial direction, and static and time dependent examples are discussed. With quadratic or Coulomblike permittivity variations, the wave functions resemble the quantum mechanical harmonic oscillator or hydrogen atom wave functions, and similar angular momentum operators are obtained.

Synthesis Of Gaussian Beam Optical Systems, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Systematic procedures are presented for determining the the optical components needed to obtain an arbitrary transformation of a propagating light ray or Gaussian beam.

H & V News

Building Services Engineering

No abstract provided.

The Impact Of A Computerized Conferencing System On Scientific Research Communities, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz

Computerized Conferencing and Communications Center Reports

The author is indebted to Murray Turoff for coauthoring the sections describing the EIES system and for his suppport and encouragement for this study at all stages. Mary Anne Solimine served as a research assistant, supervising the distribution, coding and tabulations of questionnaire responses. Without her diligent efforts, the study would not have been possible. Ann Marie Rabke, Joanne Garofalo, Diane Price, Duchess Brooks, Margaret Wnorowski, Christine Naegle, Sonia Khalil, and Marion Whitescarver provided valuable assistance with coding and data entry and editing tasks. Larry Landwebber was most cooperative in providing access to the Theory Net group. Alan Leurck, Thomas …

Traffic Accidents In Kentucky (1978), Kenneth R. Agent

Kentucky Transportation Center Research Report

Highway locations having an abnormal history of accidents should be identifiable in some way. Average and critical accident numbers and rates must be known for similar locations. Averages have been determined previously for rural highways, but it is necessary to update those numbers and to determine rates for urban areas. A detailed picture of traffic accidents in Kentucky in 1978 is presented.

Average rates in terms of accidents per 100 million vehicle-miles (160 million vehicle-kilometers) were calculated for various classifications of rural and urban highways. Also, average rates in terms of accidents per million vehicles were determined for 0.3-mile (0.48-km) …

A Purely Chemical Nitrogen Dioxide Laser, Conrado Mendoza Malalis

Theses

Purely chemical lasers promise to provide future high-power lasers for remote installations, airplanes, ships and in space without the necessity of external electric power, sources.

This study is about the design and construction of a new, gas phase purely chemical NO₂ laser, based on the reaction of NO + O₃ + NO≠₂ + O₂. The vibrationally excited NO≠₂ species at 1-40 mm Hg total pressure is the source of energy (photons) for the laser. A series of computer program calculations on the reaction kinetics and relaxational processes involved have also been made, …

The Effect Of Adhesive Bond Strength Of Selected Species Of Laminated Wood, Daniel L. Henderson

Graduate Research Papers

Wood laminating has been used by man for centuries and is a very important part of industrial enterprises today. In most woodworking textbooks reviewed however, those sections devoted to wood laminating are typically miniscule. Topics are hastily covered and only general information is provided. This study has been conducted in order to provide more adequate explanation of the laminating process in addition to those presently available and to explore the interrelationship of laminated components with the ultimate function of the product. A glance at any furniture manufacturing or construction industry periodical, however, will show the importance of wood laminating in …

Sessions, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

In-Situ Measurements Of Blast Seismic Waves And Their Safety Distance, Rui-Geng Zhu, Li Zhen

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Empirical formulae and their applications are given after systematically analysing the seismic wave data as measured in various blasting operations. The computed results are ln close agreement with the field measured data

Session 1a: Opening Remarks And Moderator's Report, F. E. Richart Jr., Richard D. Woods

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Behavior Of Interfaces Between Structural And Geologic Media, C. S. Desai

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The main objective of this paper is to identify and discuss the subject of the effect of interface behavior on the overall soil-structure interaction in building foundation systems. A brief review of the previous approaches based on the assumption of compatibility between the structure and soil is followed by a discussion of the recent efforts toward inclusion of relative slip, debonding and rebonding at interfaces. Here available models in the context of the lumped parameter and finite element approaches are reviewed. A number of models used in static and dynamic analyses are presented, and the difficulties associated with those based …

Soil Liquefaction Seismic Risk Analysis Based On Post 1979 Earthquake Observations In Montenegro, K. Talaganov, J. Petrovski, V. Mihailov

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The scale and consequences of soil liquefaction during April 15, 1979 Montenegro earthquake rose a problem of explanation of this phenomena and assessment of the ground behaviour during future earthquakes. The analysis, the details and results presented in this paper is divided into two parts: The first part comprises soil liquefaction during Aprill5 1979 earthquake including the analysis of both geotechnical conditions and excitation potential inducing them. In order to realise the scale and the properties of the phenomenon, distribution of the locations with manifestations likely to have been induced by soil liquefaction, as observed on the ground surface and …

The Potential Of In-Space Research On Liquefaction Phenomena And Related Soil Behavior, Nicholas C. Costes, George C. Marshall, Stein Sture

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Because the constitutive laws for soils are governed mainly by interparticle friction, all aspects of their mechanical behavior depend strongly on gravitational body forces. This fact poses serious limitations on the formulation of a materially objective soil constitutive theory, based on experimentation performed on earth. In particular, the presence of the earth's gravity prohibits the design of controlled experiments to properly simulate a variety of critical phenomena associated with the dynamic response of soils to seismic excitation in a very low effective confining stress field. For these reasons, the advent of the space age and, more specifically, the capabilities of …

Table Of Contents, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Session 4: Discussion And Replies, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Free Response Of Shells On Flexible Foundation, R. M. Belkune, J. C. Vyas

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Free response of axisymmetric shells resting on flexible foundation in their asymmetric modes is studied using Finite Elements based on harmonic formulation. Influence of various parameters, such as subgrade modulus, proximity of boundary, density ratio, shear wave velocity, embedment of structure and depth of flexible foundation., on free response is studied. Axisymmetric interface element with harmonic functions is developed and introduced between the raft slab and foundation media.

Seismic Stability Indices Of Earth Structure, M. P. Singh

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Indices like cyclic damage and factor of safety are often used to quantify stability of soil systems subjected to earthquake loads. The methods used to obtain these indices are described; the relationship between cyclic damage and factor of safety through the concept of uniform stress equivalent time history is explored. For evaluation of a soil system design, the use of a direct approach is proposed. Evaluation of this approach by a simulation study is outlined. This approach, can use response spectra directly as seismic design input, and it provides an acceptable procedure for seismic stability prediction of soil systems.

Electrical Characterization Of Soil For In-Situ Measurement Of Liquefaction Potential, K. Arulanandan, S. J. Harvey, J. S. Chak

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A new method for characterizing the fundamental sand properties with electrical parameters is described. Correlations are established between the electrical parameters and relative density, D_r, cyclic stress ratio, τ/ σ'₀, and the parameter K_2max. An electrical probe, used to measure the electrical parameters in situ, is described. Field measurements, taken with the probe at one of the 1906 San Francisco earthquake sites, indicate that this is a viable alternative for the in situ evaluation of liquefaction potential.

Program Of The Conference, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Shear Moduli And Damping Of Cohesive Soils Under Earthquake Loads, Wen-Yao Hu, Tian-Long Wang

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

To investigate the dynamic properties of soils under earthquake loading conditions, a series of cyclic triaxial compression tests vas carried out on undisturbed saturated samples of cohesive soils from Tianjin. It has come to the conclusion that variation of damping ratio, as well as shear modulus, with strain amplitude may be expressed by an empirical formula. Its normalized form can be shown by a family of curves or a band zone with shrunken ends. New empirical equations used for evaluating elastic or initial shear modulus G₀ and maximum shear stress τ_max have been suggested. For the two parameters, …

Interface Element For Propagation In Layered Media, V. R. Gadhinglajkar, R. M. Belkune, C. K. Ramesh

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

An interface element which accounts for the relative displacement between two layers through its stiffness properties and loss of energy through its damping properties has been developed. lts behaviour under static, free vibration, transient load and wave propagation in layered media has been studied.

Session 2: Discussion & Replies, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.

Numerical Computation Of Earth-Pressures During Earthquakes, D. Aubry, D. Chouvet

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

After reviewing sorre important features of earth pressures against retaining wall during earthquakes the authors propose an implicit-explicit scherre for time integration of the elastoplastic equations in dynamics. Same results obtained with the developed computer code are presented and discussed.

Dynamic Response Of Concrete Pavement, S. S. Bandyopadhyay

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The dynamic response of concrete pavement to a moving line load has been studied by idealizing the subgrade with different viscoelastic models. Complex Fourier Transformation has been used to solve the soil-structure interaction problem. The results are presented in non-dimensional form. The appropriate choice of models and the corresponding material constant values for different types of bases and/or subgrade generally used under concrete pavement have been discussed.

Effect Of Soil Parameters On High Velocity Projectile Penetration, D. Z. Yankelevsky

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

A parameter analysis is performed on an analytical penetration model which has been recently developed. Figures are plotted to show how the disturbed zone size, parameters of displacement and stress fields and dynamic section pressure are dependent on soil compressibility, shear strength and mass density. Main results are presented and discussed.

Dynamic Response Of An Embedded Structure Generated By A Sh-Wave, G. S. Yeh, T. W. Lin

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

In this investigation, a mathematical hybrid model developed previously is employed to study soil-structure interaction of embedded structure. In the analysis, the near field including the embedded structure and its surrounding foundation soil is modelled with a conventional finite element mesh, and the far field is modelled as a semi-infinite medium with a hemi-spherical pit. The impedance functions at the nodes around the special element, which have been determined analytically, can represent the behavior of outgoing propagation of waves. A concept of superposition is proposed to analyze the response of an embedded structure excited by an incoming SH-wave. The governing …

Offshore Earthquake Geotechnology — Second Part, P. B. Selnes

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

This second part of the paper discusses submarine slides and acoustic waves from earthquakes, and gives a general overview of aseismic design procedures. Problems which are specific or especially important for the offshore environment are pointed out and discussed in more detail.

A Simple Method Of Estimating Seismic Pressures From Cohesive Soils Against Basement Walls, P. W. Taylor, Z. Lndrawan

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Although this problem arises frequently in design practice, there is little guidance for the designer in current literature. The proposed method entails estimating the free-field soil deformation caused by a horizontal acceleration. Dynamic increase in earth pressure against an (effectively rigid) wall is assumed to be proportional to the free-field deformation, relative to the base of the wall, with an upper limit equal to full passive pressure. Dynamic pressures calculated using this method are compared with field evidence from published records of observations made on a building in Yokohama during an earthquake.

Pavement Soil Interaction Under Dynamic Loads, Bhagirath Lall, Rajendra Puri, J. K. Juneja

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Different types of model pavements were subjected to forced vertical vibration with a view to studying the attenuation properties of Rayleigh Waves. The effect of the road base materials is studied along with the effect of the change in the thickness of the wearing course. The effect of different corner angles at the edge of the road is also investigated. The characteristics of geometric and material damping are discussed in relation to transmission and attenuation of vibration.

Isolation Of Machine Foundations By Barriers, A. Sridharan, M. V. Nagendra, T. Parthasarathy

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Experimental investigation has been carried out to study the effects due to isolation of foundations subjected to vertical vibration on the displacement amplitude. Tests were conducted on an embedded footing of contact area 45 x 45cm. with different embedments and some on the surface of natural ground. Three isolation barriers viz. air gap, saw dust and sand of various depths were used. From the results of the investigation it was found that an open trench (air gap) around the foundation reduces the displacement amplitude around the footing considerably to an extent of about 75%. Saw dust as a barrier, although …