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Characterizing sub-surface microclimates used by a climate-sensitive species, the American pika
The American pika is uniquely constrained to habitats of blocky debris. In this habitat, the availability of temperate sub-surface microclimates allows this temperature-sensitive species to survive the variable conditions of surface climate. The effect to which surface heterogeneity can influence the temperature regimes of the talus sub-surface has yet to be fully understood and previous studies have relied solely upon metrics of surface climate to estimate suitable habitat and future pika range. Here, I characterized sub-surface temperatures relative to elevation, aspect, near-surface temperature and microhabitat features such as talus depth and canopy cover to begin understanding the extent to which different surface features can affect pika habitat. Talus temperatures were found to be significantly affected by elevation, aspect, depth of sub-surface habitat, and a temperature sensor’s placement overwinter, which was between talus, the talus interface, and the adjacent area of meadow or canopy cover
Intermediate File Servers in a Distributed File System Environment
A component of the Institutional File System (IFS), the intermediate file server addresses scaling and interoperability issues on the University of Michigan campus. The IFS is based on AFS, a distributed file system from Transarc. Intermediate servers provide protocol translation that enables non-AFS clients to easily access the distributed file system. For example, Macintosh users can manipulate UNIX files that reside on a server by moving folders and icons, just as they would manipulate local Macintosh files. Intermediate servers also offer other benefits, such as multi-level caching and data preloading, that increase the capacity of the network by reducing the load on central servers.http://deepblue.lib.umich.edu/bitstream/2027.42/107959/1/citi-tr-92-4.pd
Strategic Nuclear Weapons for Planetary Defense
The planet Earth is continually under bombardment. Each day, roughly 100 tons of small meteoroids and space debris – some as large as a meter in diameter, but most smaller than a grain of sand – strike the atmosphere. Moving at speeds in excess of 40,000 kilometers per hour, these meteoroids are often seen as bright streaks in the sky as they burn up from atmospheric friction. Fortunately, because they are consumed high in the atmosphere, meteoroids and space dust pose no threat to humans or other life on Earth
An Environment for "Sniffing" DCE-RPC Traffic
The ability to watch the network traffic generated by client and server applications can greatly assist in both understanding how a client/server application functions, as well as identifying problem areas. At the Center for Information Technology Integration (CITI), we use the Open Software Foundation's Distributed Computing Environment (OSF/DCE). To examine network traffic in this client/server environment, we developed two tools: one based on the Network General Sniffer, and one based on the IBM RS 6000 AIX operating system.http://deepblue.lib.umich.edu/bitstream/2027.42/107946/1/citi-tr-93-4.pd
Auto-Concealment of Supersymmetry in Extra Dimensions
In supersymmetric (SUSY) theories with extra dimensions the visible energy in
sparticle decays can be significantly reduced and its energy distribution
broadened, thus significantly weakening the present collider limits on SUSY.
The mechanism applies when the lightest supersymmetric particle (LSP) is a bulk
state-- e.g. a bulk modulino, axino, or gravitino-- the size of the extra
dimensions larger than ~ cm, and for a broad variety of visible
sparticle spectra. In such cases the lightest ordinary supersymmetric particle
(LOSP), necessarily a brane-localised state, decays to the Kaluza-Klein (KK)
discretuum of the LSP. This dynamically realises the compression mechanism for
hiding SUSY as decays into the more numerous heavier KK LSP states are favored.
We find LHC limits on right-handed slepton LOSPs evaporate, while LHC limits on
stop LOSPs weaken to ~350-410 GeV compared to ~700 GeV for a stop decaying to a
massless LSP. Similarly, for the searches we consider, present limits on direct
production of degenerate first and second generation squarks drop to ~450 GeV
compared to ~800 GeV for a squark decaying to a massless LSP. Auto-concealment
typically works for a fundamental gravitational scale of ~10-100 TeV, a
scale sufficiently high that traditional searches for signatures of extra
dimensions are mostly avoided. If superpartners are discovered, their prompt,
displaced, or stopped decays can also provide new search opportunities for
extra dimensions with the potential to reach ~ GeV. This mechanism
applies more generally than just SUSY theories, pertaining to any theory where
there is a discrete quantum number shared by both brane and bulk sectors.Comment: 22 pages, 13 figures. Minor changes to match published versio
Collective Bargaining—Faculty Status Under the National Labor Relations Act—NLRB v. Yeshiva University, 582 F.2d 686 (2d Cir. 1978), cert. granted, 99 S. Ct. 1212 (1979)
Supervisors and managerial employees were originally excluded from the NLRA\u27s protections to solve problems caused by the unionization of decisionmakers working in the hierarchy of business organizations. Decisionmaking at Yeshiva, however, as in much of higher education, is organized on a non-hierarchical, collective basis. The Yeshiva court implicitly assumed, despite the University\u27s non-hierarchial decisionmaking structure, that the policies underlying the exclusion of supervisors and managerial employees would be served by denying faculty the right to bargain collectively. This note tests that assumption. It examines the extent to which the purposes for excluding supervisory and managerial personnel from the NLRA\u27s protections are served by denying Yeshiva\u27s faculty the right to form a bargaining unit
Tectonics, sedimentation, and hydrocarbon potential of the Reelfoot aulacogen
Thesis (M.S.)--University of Oklahoma, 1985.The Reelfoot aulacogen, an early Paleozoic failed-rift basin, lies concealed beneath the Gulf Coastal Plain strata of the upper Mississippi Embayment. Many similarities exist between the geologic history of the Reelfoot aulacogen and the coeval histories of the adjacent Paleozoic continental margins of North America. Plate tectonic theory provides useful concepts to explain the histories of both continental margins and intracratonic structural features.
Widespread continental extension (continental break-up) occurred in the latest Precambrian-Early Cambrian and initiated rifting in intracratonic areas. Rifting proceeded in some areas to drifting with generation of oceanic crust and formation of the Paleozoic continental margins of North America. Other areas, such as the Reelfoot rift, ceased rifting and subsided passively to form broad downwarped troughs above rift graben systems. Post-rifting subsidence in the Reelfoot area resulted primarily from cooling of the anomalous lithosphere that formed beneath the rift during extension and corresponds to post-rifting, passive subsidence of the continental margins.
Convergent plate interactions affect the interiors of continents as well as their margins, especially along lines of pre-existing weakness. Late Paleozoic plate convergences and continental collisions caused both compressive and extensional reactivation of certain ancient normal faults in the Reelfoot aulacogen that had formed initially during rifting. Post-Paleozoic faulting, generally related to reactivated basement normal faults, occurred in the Late Cretaceous, Tertiary, and Quaternary. Earthquakes in the Reelfoot aulacogen indicate continued faulting that results from the present-day stress field acting on certain ancient crustal weaknesses, usually reactivated rift stage faults.
The hydrocarbon potential of the Reelfoot area is discussed in terms of source rocks, reservoirs, and traps. Potential hydrocarbon prospects include broad anticlines, horst block highs, forced and compaction folds over block edges, normal and reverse faulted anticlines, submarine fans, carbonate buildups and shoals, stratigraphic pinchouts, truncation traps, unconformities, fracture reservoir trends, and shelf-basin hingelines. Reflection seismic profiles show examples of prospect types
On the Deflexion of Anisotropic Structural Composite Aerodynamic Components
This paper presents closed form solutions to the classical beam elasticity differential equation in order to effectively model the displacement of standard aerodynamic geometries used throughout a number of industries. The models assume that the components are constructed from in-plane generally anisotropic (though shown to be quasi-isotropic) composite materials. Exact solutions for the displacement and strains for elliptical and FX66-S-196 and NACA 63-621 aerofoil approximations thin wall composite material shell structures, with and without a stiffening rib (shear-web), are presented for the first time. Each of the models developed is rigorously validated via numerical (Runge-Kutta) solutions of an identical differential equation used to derive the analytical models presented. The resulting calculated displacement and material strain fields are shown to be in excellent agreement with simulations using the ANSYS and CATIA commercial finite element (FE) codes as well as experimental data evident in the literature. One major implication of the theoretical treatment is that these solutions can now be used in design codes to limit the required displacement and strains in similar components used in the aerospace and most notably renewable energy sector
Minimisation of energy consumption variance for multi-process manufacturing lines through genetic algorithm manipulation of production schedule
Typical manufacturing scheduling algorithms do not consider the energy consumption of each job, or its variance, when they generate a production schedule. This can become problematic for manufacturers when local infrastructure has limited energy distribution capabilities. In this paper, a genetic algorithm based schedule modification algorithm is presented. By referencing energy consumption models for each job, adjustments are made to the original schedule so that it produces a minimal variance in the total energy consumption in a multi-process manufacturing production line, all while operating within the constraints of the manufacturing line and individual processes. Empirical results show a significant reduction in energy consumption variance can be achieved on schedules containing multiple concurrent jobs
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