Shore fish community structure off the Jordanian Red Sea coast was determined on fringing coral reefs and in a seagrass-dominated bay at 6 m and 12 m depths. A total of 198 fish species belonging to 121 genera and 43 families was recorded. Labridae and Pomacentridae dominated the ichthyofauna in terms of species richness and Pomacentridae were most abundant. Neither diversity nor species richness was correlated to depth. The abundance of fishes was higher at the deep reef slope, due to schooling planktivorous fishes. At 12 m depth abundance of fishes at the seagrass-dominated site was higher than on the coral reefs. Multivariate analysis demonstrated a strong influence on the fish assemblages by depth and benthic habitat. Fish species richness was positively correlated with hard substrate cover and habitat diversity. Abundance of corallivores was positively linked with live hard coral cover. The assemblages of fishes were different on the shallow reef slope, deep reef slope and seagrass meadows. An analysis of the fish fauna showed that the Gulf of Aqaba harbours a higher species richness than previously reported. The comparison with fish communities on other reefs around the Arabian Peninsula and Indian Ocean supported the recognition of an Arabian subprovince within the Indian Ocean. The affinity of the Arabian Gulf ichthyofauna to the Red Sea is not clear.

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Community structure and biogeography of shore fishes in the Gulf of Aqaba, Red Sea

Probabilistic hazard for seismically induced tsunamis: accuracy and feasibility of inundation maps

Impact of the 1991 Gulf War on the coastal environment and ecosystems: Current status and future prospects

The general area of elastodynamics is divided into four more limited topics including, stress-wave propagation, vibration and impact, fracture propagation and quasi-static transients. The application of dynamic photoelasticity to each topic is discussed. Recording methods used in dynamic photoelasticity which are reviewed include the high-speed framing camera, the Cranz-Schardin system, Q-switched ruby lasers, and a stopaction strobe system. Advantages and disadvantages of each method of recording are covered. Analysis procedures used in interpreting the dynamic isochromatic-fringe patterns are described. Examples are illustrated where separation of the principal stresses is possible and a calibration method for determining the dynamic material-fringe valuef
σ
* is reviewed. Finally, four applications of dynamic photoelasticity to problems arising in geophysics, fracture mechanics, flaw detection and mining are briefly reviewed to show the versatility of the dynamic photoelastic method are described.

An introduction to dynamic photoelasticity

Brachyuran decapods of the families Grapsidae and Ocypodidae are a dominant faunal element of intertidal flats and mangroves in the Arabian Gulf and the Gulf of Oman. Recent collections along the coasts of the U.A.E. and Saudi Arabia and examination of material from other parts of the Gulf revealed in total six species of grapsid and 21 taxa (species and subspecies) of ocypodid crabs occurring in these habitats within the Arabian Gulf. Great differences in species diversity and composition exist between the different parts of the Arabian Gulf. Maximum diversity was observed for the easternmost part of the U.A.E. (Ras al Khaimah, Umm al Quwain) and for Kuwait. Highly reduced species numbers were found along the shorelines of Abu Dhabi and Saudi Arabia. The most likely factor causing this pattern is salinity. Zoogeographically it appears, that most of the Arabian Gulf species are of an ‘eastern’ (Indian) origin. ‘Western’ (East African and Red Sea) elements are restricted to the south-eastern part of the Gulf (coast of the U.A.E.) and to the Gulf of Oman.

Taxonomic Composition, Distribution and Zooeoahic Relationships of the Grapsid and Ocypodid Crab Fauna of Intertidal Soft Bottoms in the Arabian Gulf

A shortcoming of the conventional holographic interferometer used in photoelasticity is that, for the double-exposure cases, the resulting fringe patterns are a complex combination of conventional isochromatic and isopachic fringes. This paper describes a holographic interferometer that may be used to obtain separate but simultaneous isochromatic- and isopachic-fringe patterns for photoelastic models in states of plane stress. The method requires a model with a partially reflecting front surface. Isopachics, which are proportional to the thickness change, are recorded using holographic interferometry from the transmitted light. The isochromatics are obtained from the transmitted light by conventional means. General equations relating the surface displacement of the specimen to the observed fringe patterns are developed, and examples of static and dynamic loadings are shown.

https://link.springer.com/content/pdf/10.1007/BF02328816.pdf

A neoteric interferometer for use in holographic photoelasticity

: A summary is given of research concerned with the experimental investigation of the stresses developed in a solid fuel rocket motor when subjected to different loading conditions Also, a detailed report is given of a study involving scattered light photoelasticity used to determine the stress distribution in a three dimensional, solid propellant rocket motor The model was a case bonded solid propellant with a star grain internal boundary Stresses were induced by both internal pressure and a uniform temperature change The uniform temperature change simulated the shrinkage stresses imposed on actual propellants in storage The pressure load simulated part of the loads developed in firing a rocket The model material was polyurethane rubber which is similar to the binder material in actual rockets The model construction and data analysis are discussed in detail, and the results are presented in graphical form (Author)

Final Report for Phase II

A set of equations is presented and the effect of rotation of the secondary principal stress axes is discussed. The equations, general and relatively simple, adequately describe observed results. In studying the equations, a better understanding of the rotational effect can be achieved, and a technique is suggested which can eliminate any error resulting from rotation. This technique and the concepts involved are substantiated with experimental evidence and reported in this paper.

Effect of rotating secondary principal axes in scattered-light photoelasticity

A newly developed concept, called thescattered-light, rosette, is used to determine the state of stress on a free surface. Three simultaneous, polarized-light beams intersecting at a surface point yield sufficient scattered-light photoelastic data to evaluate the stresses at a surface point. After initial calibration, the surface-stress analysis consists of a series of photographs, one photograph for each point of interest. General equations are derived which are valid for any three light beams intersecting at a surface point on a stressed, photoelastic material. Simplifications of the general equations and techniques are also noted. Stresses obtained from the scattered-light-rosette analysis are compared with the known solutions for two problems.

Scattered-light rosette

Scattered-light photoelasticity, a nondestructive technique, is used to determine the stress distribution in a three-dimensional, solid-propellant rocket motor. The model is a case-bonded solid propellant with a stargrain internal boundary. Stresses are induced by internal pressure. The pressure load simulates part of the stresses developed in firing a rocket. The model material is polyurethane rubber which is similar to the binder material in actual rockets. The model construction and data analysis are discussed in detail, and the results are presented in graphical form.

W. F. Ranson

Papers

A neoteric interferometer for use in holographic photoelasticity

Final Report for Phase II

Effect of rotating secondary principal axes in scattered-light photoelasticity

Scattered-light rosette

Scattered-light photoelastic stress analysis of a solid-propellant rocket motor