AIGO: a southern hemisphere detector for the worldwide array of ground-based interferometric gravitational wave detectors

This paper describes the proposed AIGO detector for the worldwide array of interferometric gravitational wave detectors. The first part of the paper summarizes the benefits that AIGO provides to the worldwide array of detectors. The second part gives a technical description of the detector, which will follow closely the Advanced LIGO design. Possible technical variations in the design are discussed

Superposition method for analysis of free-edge stresses

Superposition techniques were used to transform the edge stress problem for composite laminates into a more lucid form. By eliminating loads and stresses not contributing to interlaminar stresses, the essential aspects of the edge stress problem are easily recognized. Transformed problem statements were developed for both mechanical and thermal loads. Also, a technique for approximate analysis using a two dimensional plane strain analysis was developed. Conventional quasi-three dimensional analysis was used to evaluate the accuracy of the transformed problems and the approximate two dimensional analysis. The transformed problems were shown to be exactly equivalent to the original problems. The approximate two dimensional analysis was found to predict the interlaminar normal and shear stresses reasonably well

Plans for the LIGO–TAMA joint search for gravitational wave bursts

We describe the plans for a joint search for unmodelled gravitational wave bursts being carried out by the LIGO and TAMA Collaborations using data collected during February–April 2003. We take a conservative approach to detection, requiring candidate gravitational wave bursts to be seen in coincidence by all four interferometers. We focus on some of the complications of performing this coincidence analysis, in particular the effects of the different alignments and noise spectra of the interferometers

A new look at numerical analyses of free-edge stresses in composite laminates

The edge stress problem for a + or - 45 deg graphite/epoxy laminate was examined. The reliability of the displacement formulated finite element method in analyzing the edge stress problem was investigated. Analyses of two well known elasticity problems, one involving a stress discontinuity and one a singularity, showed that the finite element analysis yields accurate stress distributions everywhere except in two elements closest to the stress discontinuity of singularity. Stress distributions for a + or - 45 deg laminate showed the same behavior near the singularity found in the well known problems with exact solutions. The displacement formulated finite element method appears to be a highly accurate technique for calculating interlaminar stress in composite laminates. The disagreement among the numerical methods was attributed to the unsymmetric stress tensor at the singularity

Arm cavity resonant sideband control for laser interferometric gravitational wave detectors

We present a new optical control scheme for a laser interferometric gravitational wave detector that has a high degree of tolerance to interferometer spatial distortions and noise on the input light. The scheme involves resonating the rf sidebands in an interferometer arm cavity

Oyster Spatfall in Virginia Rivers: 1982 Annual Summary

The Virginia Institute of Marine Science (VIMS) conducts weekly surveys from June through early October to obtain oyster spatfall information. Spat counts are made from oyster shells strung on wire and suspended from stakes on public and private beds. The number of spat on shells are counted each week of the spawning season to determine the potential of a particular area for receiving a strike and to predict the most likely period the strikes will occur

Geometrically nonlinear analysis of adhesively bonded joints

A geometrically nonlinear finite element analysis of cohesive failure in typical joints is presented. Cracked-lap-shear joints were chosen for analysis. Results obtained from linear and nonlinear analysis show that nonlinear effects, due to large rotations, significantly affect the calculated mode 1, crack opening, and mode 2, inplane shear, strain-energy-release rates. The ratio of the mode 1 to mode 2 strain-energy-relase rates (G1/G2) was found to be strongly affected by he adhesive modulus and the adherend thickness. The ratios between 0.2 and 0.8 can be obtained by varying adherend thickness and using either a single or double cracked-lap-shear specimen configuration. Debond growth rate data, together with the analysis, indicate that mode 1 strain-energy-release rate governs debond growth. Results from the present analysis agree well with experimentally measured joint opening displacements

The origin and extent of oyster reefs in the James River, Virginia

The public oyster grounds (Baylor Survey Grounds) in the James River, VA, were studied with respect to bottom type and oyster density from 1978 to 1981. Approximately 10,118 ha (25,000 acres) were investigated using an electronic positioning system to establish station locations. Bottom types were determined using probing pipes, patent tongs, and an acoustical device. About 17.1% of the bottom was classified as consolidated oyster reef, and 47.5% was moderately productive mud-shell or sand-shell bottoms. The remaining 35.4% was rated as unsuitable for oyster culture. The surface configuration of oyster reef areas in the James River is similar to those in coastal lagoons· along the Gulf of Mexico. They are thought to have developed in the James River as they did in the Gulf of Mexico area as sea level rose during the Holocene Period

An investigation, testing and modifying of gear to harvest oysters and shell : final contract report for the period 1 July, 1973 through 30 June, 1975

During the 1974-75 contract period the hydraulic escalator was modified and tested in the York and Rappahannock Rive r s . The tests showed that the harvester was capable of raising large quantities of oysters from various types of bottoms. Moreover, these oysters were not broken or crushed, were free .of silt or grit , and t he apparatus caused only minima l damage to the bottom . The modification were made from January to April and field testing began in May 1975 in t he York and Rappahannock Rivers on public and leased bottom and on several types of substrate . The device was demonstrated for oyster growers , television companies, the press, representatives of the Virginia Marine Resources Commission, the Maryland Department of Tidewater Fisheries and a representative of the National Marine Fisheries Service. A total of 16 trials or demonstrations were completed which are listed in detail chronologically i n the appendix

The public oyster bottoms in Virginia : An overview of their size, location, and productivity

The location size and extent of Virginia\u27s public oyster grounds was determined using a long pole to probe the bottom , a towed sonic device that detected shell or oysters, and by sampling the bottom with patent tongs for shell and oyster density. Station location was determined using an electronic positioning system (Raydist® ). Bottoms were classed as oyster reefs, mud-shell or sand shell (productive or potentially productive). Areas having mud or sand or those in deep water over 30 ft. (9.1 m) were considered unproductive. Average oyster harvest for seed and market size oysters over the last ten years for various areas is related to size and location of various bottom type. About 203,404 acres out of the total of about 243,000 acres of public bottom were surveyed ; about 21 .8% of the surveyed areas was classed as productive or potentially productive. Average production was low on most of these public bottoms and ranged from 84.4 bushels/acre in the Great Wicomico River to only 1.6 bushels/acre in the York River. The seven areas producing the most seed and market oysters in terms of their average annual production in Virginia bushels were: James River 432,171 ; Rappahannock River 146,999; Pocomoke and Tangier Sounds 86,150; Sea side of Eastern Shore 63,122; Great Wicomico River 41 ,622; Piankatank River and Milford Haven 39,024; and Mobjack Bay 29,730