Innovative all composite multi-pultrusion truss system for stressed arch deployable shelters

Trusses are one of the successful structural forms that have been utilised, at extended scale, since the nineteen century. Fibre composite materials are relatively new to civil engineering applications. The increased interest in using composites in civil applications can be attributed to advantages when compared to other construction materials that offset their associated costs. Using conventional approaches for truss systems in composite materials can undermine their efficiency. This is mainly due to concentration of stresses at connections which usually govern the truss design. The Military Modular Shelter System (M2S2) initiative is a research project that aims to develop a fibre composite re-deployable arched shelter system with rigid PVC or fabric cladding. The main frames are formed from modular fibre composite panels that are connected and stressed into position by prestressing cables. Different geometries can be obtained using this system by changing the number of panels per frame and the packer sizes between panels. This paper presents the development and testing of innovative fibre composite truss modules that were investigated as part of this project. The truss system is based on using multi-pultrusion sections for the chord and vertical members. Truss bracing is provided by a double skin laminated web. This structure offers many advantages including semi-ductile failure that occurred outside the joint area and ease of manufacturing. In spite of being developed for the M2S2 system, the concept is similarly applicable as a general purpose truss system

Global Linear Complexity Analysis of Filter Keystream Generators

An efficient algorithm for computing lower bounds on the global linear complexity of nonlinearly filtered PN-sequences is presented. The technique here developed is based exclusively on the realization of bit wise logic operations, which makes it appropriate for both software simulation and hardware implementation. The present algorithm can be applied to any arbitrary nonlinear function with a unique term of maximum order. Thus, the extent of its application for different types of filter generators is quite broad. Furthermore, emphasis is on the large lower bounds obtained that confirm the exponential growth of the global linear complexity for the class of nonlinearly filtered sequences

The Second Supper: A Debate Between P.C. Key, Byran, Texas, and Cecil Abercrombie, Birmingham, Alabama.

https://digitalcommons.acu.edu/crs_books/1091/thumbnail.jp

Radiocarbon measurements in the Indian Ocean aboard RVIB Nathaniel B. Palmer

Author Posting. © The Oceanography Society, 2012. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 25, no. 3 (2012): 152-153, doi:10.5670/oceanog.2012.89.Research Vessel Icebreaker Nathaniel B. Palmer departed Cape Town, South Africa, on May 3, 1996, to complete the Indian Ocean portion of the "S04" line, a circumnavigation of Antarctica that was part of the US contribution to the World Ocean Circulation Experiment (WOCE). The WOCE Line S04I voyage ended at Hobart, Tasmania, on July 4, 1996, following completion of 108 stations, despite suspension of science operations for seven days on June 8, when the Palmer was diverted to deliver emergency food supplies to Russia's Mirny Station in the Davis Sea. During this extreme south cruise, with Thomas Whitworth III (Texas A&M University) and James H. Swift (Scripps Institution of Oceanography) as co-chief scientists, a total of 816 radiocarbon samples were collected by author Key at 31 stations, and these samples were later analyzed by author McNichol at the National Ocean Sciences Accelerator Mass Spectrometry Facility at the Woods Hole Oceanographic Institution

Global ocean radiocarbon programs

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in McNichol, A., Key, R., & Guilderson, T. Global ocean radiocarbon programs. Radiocarbon, (2022): 1–13, https://doi.org/10.1017/rdc.2022.17.The importance of studying the radiocarbon content of dissolved inorganic carbon (DI14C) in the oceans has been recognized for decades. Starting with the GEOSECS program in the 1970s, 14C sampling has been a part of most global survey programs. Early results were used to study air-sea gas exchange while the more recent results are critical for helping calibrate ocean general circulation models used to study the effects of climate change. Here we summarize the major programs and discuss some of the important insights the results are starting to provide.Authors received funding from the National Science Foundation OCE-85865400 (APM) and a Woods Hole Oceanographic Technical Staff Award (APM)