Probabilistic Analysis of Large-Scale Composite Structures Using the IPACS Code

An investigation was performed to ascertain the feasibility of using IPACS (Integrated Probabilistic Assessment of Composite Structures) for probabilistic analysis of a composite fan blade, the development of which is being pursued by various industries for the next generation of aircraft engines. A model representative of the class of fan blades used in the GE90 engine has been chosen as the structural component to be analyzed with IPACS. In this study, typical uncertainties are assumed in the level, and structural responses for ply stresses and frequencies are evaluated in the form of cumulative probability density functions. Because of the geometric complexity of the blade, the number of plies varies from several hundred at the root to about a hundred at the tip. This represents a extremely complex composites application for the IPACS code. A sensitivity study with respect to various random variables is also performed

The Rosengarten zu Worms and its analogues

The Rosenqarten zu Worms, a Middle High German Dietrichepos, is unique in the area of Middle High German literature, in that it is the only work to combine two very different motifs the rosegarden and single combat between the Germanic heroes Dietrich and Siegfried. The two major versions of the Rosengarten zu Worms were analyzed in comparison with three analogous works: Laurin, Biterolf and Thidrekssaga. Comparisons and contrasts were made on the basis of the following criteria: characters, designations, motifs and topoi which appear in two or more of the works in question. Passages showing similarities were taken from two or more of the works as well, and analyzed in order to determine what connections might exist between these works. The purpose of this investigation was an attempt to provide a possible answer as to the origin of the Rosengarten zu Worms, a problem which remains unsolved by scholars\u27 previous studies. The results showed a highly probably connection between one of the major versions of the Rosengarten zu Worms and Laurin. In the past this connection has been denied by scholars. These results brought forth the conclusion that an earlier form or version of the Rosengarten zu Worms existed. Also concluded was that the earlier version of the Rosengarten zu Worms used Laurin as a source, or that both of these works were derived from the same source, which has been lost

Hearing in cetaceans : from natural history to experimental biology

Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Advances in Marine Biology 63, edited by Michael Lesser, :197-246. Academic Press (Elsevier), 2013. ISBN: 9780123942821. doi:10.1016/B978-0-12-394282-1.00004-1Sound is the primary sensory cue for most marine mammals, and this is especially true for cetaceans. To passively and actively acquire information about their environment, cetaceans have perhaps the most derived ears of all mammals, capable of sophisticated, sensitive hearing and auditory processing. These capabilities have developed for survival in an underwater world where sound travels five times faster than in air, and where light is quickly attenuated and often limited at depth, at night, and in murky waters. Cetacean auditory evolution has capitalized on the ubiquity of sound cues and the efficiency of underwater acoustic communication. The sense of hearing is central to cetacean sensory ecology, enabling vital behaviors such as locating prey, detecting predators, identifying conspecifics, and navigating. Increasing levels of anthropogenic ocean noise appears to influence many of these activities. Here we describe the historical progress of investigations on cetacean hearing, with a particular focus on odontocetes and recent advancements. While this broad topic has been studied for several centuries, new technologies in the last two decades have been leveraged to improve our understanding of a wide range of taxa, including some of the most elusive species. This paper addresses topics including how sounds are received, what sounds are detected, hearing mechanisms for complex acoustic scenes, recent anatomy and physiology studies, the potential impacts of noise, and mysticete hearing. We conclude by identifying emerging research topics and areas which require greater focus.In compiling this review, TAM was supported by the John E. and Anne W. Sawyer Endowed Fund and the Penzance Endowed Fund

Atomic layer deposition and properties of refractory transition metal-based copper-diffusion barriers for ULSI interconnect

textRefractory transition metals have played an important role in the manufacturing of microelectronic devices for interconnect applications including metal contacts, adhesion layers, and diffusion barriers. The diffusion barrier application has become crucial for the integration of copper as the choice conductor in ultra-large scale integrated (ULSI) circuit interconnect. The refractory metal tantalum has been used commercially in previous ULSI technology generations, and atomic layer chemical vapor deposition (ALD) processes for this metal are highly desired for its use in future generations. This dissertation presents surface chemistry and film growth investigations exploring tantalum ALD and an investigation of barrier film adhesion to relevant interconnect surfaces. In-situ surface analysis techniques including X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD) were used to study the fundamental adsorption behavior of TaCl5, which was used in the first reported Ta ALD process, on a polycrystalline Ta surface. Based upon these results and those of recently published works, a TaF5/Si2H6 precursor chemistry for Ta ALD was proposed. In this method, alternating half-reactions, which, in this case, are the reaction of TaF5 with a Si2H6-treated surface (the TaF5 halfreaction) and the reaction of Si2H6 with a TaF5-treated surface (the Si2H6 halfreaction), are used sequentially and repetitively to deposit a film. The adsorption and half-reactions of these precursors in the range of 303 to 523 K on polycrystalline Ta were studied in ultra-high vacuum using XPS, TPD and secondary ion mass spectrometry. These half-reactions were subsequently used in practice to deposit thin Ta films in a specially designed, research-scale ALD reactor. This is the first non-plasma enhanced method reported to deposit Ta by ALD. Finally, the adhesion properties of similar tungsten carbide thin films to SiO2 and candidate low-permittivity dielectric substrates was characterized by the four-point bend delamination technique.Chemical Engineerin

C AND M BOTTOM LOADING FURNACE TEST DATA

The test was performed to determine the response of the HBL Phase III Glovebox during C&M Bottom Loading Furnace operations. In addition the data maybe used to benchmark a heat transfer model of the HBL Phase III Glovebox and Furnace