Tailoring the local interaction between graphene layers in graphite at the atomic scale and above using scanning tunneling microscopy.

With recent developments in carbon-based electronics, it is imperative to understand the interplay between the morphology and electronic structure in graphene and graphite. We demonstrate controlled and repeatable vertical displacement of the top graphene layer from the substrate mediated by the scanning tunneling microscopy (STM) tip-sample interaction, manifested at the atomic level as well as over superlattices spanning several tens of nanometers. Besides the full-displacement, we observed the first half-displacement of the surface graphene layer, confirming that a reduced coupling rather than a change in lateral layer stacking is responsible for the triangular/honeycomb atomic lattice transition phenomenon, clearing the controversy surrounding it. Furthermore, an atomic scale mechanical stress at a grain boundary in graphite, resulting in the localization of states near the Fermi energy, is revealed through voltage-dependent imaging. A method of producing graphene nanoribbons based on the manipulation capabilities of the STM is also implemented.

The Younger Dryas and millenial-scale oceanographic variability in the Sulu Sea, tropical western Pacific

EXTRACT (SEE PDF FOR FULL ABSTRACT): A high resolution, AMS carbon-14-dated sediment record from the Sulu Sea clearly indicates the Younger Dryas climatic event affected the western equatorial Pacific. Presence of the Younger Dryas in the tropical western Pacific indicates this climatic event is not restricted to the North Atlantic nor to high latitudes, but is global in extent.

Semiempirical down-scaling of GCM output to the local scale for temperature, precipitation, and runoff

EXTRACT (SEE PDF FOR FULL ABSTRACT): An empirically derived multiple linear regression model is used to relate a local-scale dependent variable (either temperature, precipitation, or surface runoff) measured at individual gauging stations to six large-scale independent variables (temperature, precipitation, surface runoff, height to the 500-mbar pressure surface, and the zonal and meridional gradient across this surface). ...The area investigated is the western United States. ... The calibration data set is from 1948 through 1988 and includes data from 268 joint temperature and precipitation stations, 152 streamflow stations (which are converted to runoff data), and 24 gridded 500-mbar pressure height nodes.

An overview of decadal to century time-scale variability in the climate system

EXTRACT (SEE PDF FOR FULL ABSTRACT): Time scales extracted from high-resolution proxy records and observations indicate that the spectrum of climate variability exhibits significant power in the range of decades to centuries superimposed on a red-noise continuum. The classical view of climate variability is based on the concept that observed fluctuations have their origin in periodic forcings on the same time scale. ... Instead, it is proposed that these fluctuations are linked to interactions within and between the different climate system components.

Offshore coho salmon populations near the Pacific Northwest and large-scale atmospheric events

EXTRACT (SEE PDF FOR FULL ABSTRACT): Catch of coho salmon off the coast of Washington and Oregon since 1925 appears to be related to large-scale events in the atmosphere, which in turn affect ocean currents and coastal upwelling intensities in the northeastern Pacific. At least two time scales of variations can be identified. The first is that of the El Nino/Southern Oscillation phenomenon giving rise to an irregular cycle of between 3 to 7 years. ... The second time scale of variation seems to have a periodicity of about 20 years, although this is based on a limited dataset. ... This paper endeavors to describe how, if real, these atmospheric/oceanic effects are integrated and might affect the salmon catch. The possibility must also be considered that the atmospheric events are symbiotically related to the oceanic events and, further, that both may be enmeshed in even longer-term variability of climate.

Interannual to decadal time-scale variations in glacier mass balance [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): The mass balance of glaciers depends on the seasonal variation in precipitation, temperature, and insolation. For glaciers in western North America, these meteorological variables are influenced by the large-scale atmospheric circulation over the northern Pacific Ocean. The purpose of this study is to gain a better understanding of the relationship between mass balance at glaciers in western North America and the large-scale atmospheric effects at interannual and decadal time scales.

Evidence for changes in large-scale upwelling in the California Current over the past 700 years [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Bidecadal radiocarbon measurements on tree rings provide a detailed series of carbon-14 activities at isotopic equilibrium with atmospheric carbon dioxide. ... Most marine environments do not permit development of a comparable series of carbon-14 ages with which to compare the terrestrial tree ring series. However, we have recently begun work on such a series using material from the varved sediments of the Santa Barbara Basin off southern California. ... We now have a nearly continuous record of carbon-14 dates representing the age of the water over the upper 100 meters. ... The ocean reservoir ages show an increase prior to 1450 and a progressive decrease with time after 1450. Although there may be other explanations, we believe this trend is principally the result of changes in large-scale upwelling of water from below 500 meters. These changes were probably also associated with changes in the intensity of the California Current.

Response of Pacific Northwest vegetation to large-scale changes in climate during the last 100,000 years [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): Paleoclimatic variations in western North America depend on a hierarchy of temporal and spatial controls that can be examined using a combination of modeling studies and data synthesis. ... The regional vegetation response to large-scale changes in the climate system of the last 21,000 years is used as a conceptual model to help explain earlier vegetation and climate at two localities.

DEVELOPMENT OF THE WAVE CONTOURING RAFT.

The wave contouring raft system is the outcome of ideas initiated and developed by Sir Christopher Cockerell from 1972 onwards. His objective was to develop a wave energy device which is within the bounds of current technology. It should consist of simple, relatively small units, amenable to quantity production, which would enable a power generating system to be built up and commissioned in stages according to needs and production capability. This thinking led to the investigation of chains of pontoons, hinged together so that the passage of a wave down the chain causes the pontoons to oscillate relative to one another. Energy is extracted from the sea by applying a torque about the hinges to damp the motion. The work has involved extensive model testing in wave tanks and the building and testing of a 3-unit 1/10 scale power generating installation in the Solent, as well as design studies for a full size installation for Atlantic conditions.

Tribological properties of mems materials measured on a small-scale device

Micro-electro-mechanical systems, MEMS, is a rapidly growing interdisciplinary technology within the general field of Micro-Systems Technology which deals with the design and manufacture of miniaturised machines with major dimensions at the scale of tens, to perhaps hundreds, of microns. Because they depend on the cube of a representative dimension, component masses and inertias rapidly become small as size decreases whereas surface and tribological effects, which often depend on area, become increasingly important. Although MEMS components and their areas of contact are small, tribological conditions, measured by contact pressures or acceptable wear rates, are demanding and technical and commercial success will require careful measurement and precise control of surface topography and properties. Fabrication of small numbers of MEMS devices designed to test potential material combinations can be prohibitively expensive and thus there is a need for small scale test facilities which mimic the contact conditions within a micro-machine without themselves requiring processing within a full semiconductor foundry. The talk will illustrate some initial experimental results from a small-scale experimental device which meets these requirements, examining in particular the performance of Diamond-Like-Carbon coatings on a silicon substrate. Copyright © 2005 by ASME.

The brave new era of human genetic testing

The commercialization of 'big science' is in full swing, leading to situations in which the ethical principles of academia are beginning to be compromised. This is exemplified by the profitable business of genetic ancestry testing. The goals of this sort

Testing of Depth-Encoded Hough Voting for Infrastructure Object Detection

The lack of viable methods to map and label existing infrastructure is one of the engineering grand challenges for the 21st century. For instance, over two thirds of the effort needed to geometrically model even simple infrastructure is spent on manually converting a cloud of points to a 3D model. The result is that few facilities today have a complete record of as-built information and that as-built models are not produced for the vast majority of new construction and retrofit projects. This leads to rework and design changes that can cost up to 10% of the installed costs. Automatically detecting building components could address this challenge. However, existing methods for detecting building components are not view and scale-invariant, or have only been validated in restricted scenarios that require a priori knowledge without considering occlusions. This leads to their constrained applicability in complex civil infrastructure scenes. In this paper, we test a pose-invariant method of labeling existing infrastructure. This method simultaneously detects objects and estimates their poses. It takes advantage of a recent novel formulation for object detection and customizes it to generic civil infrastructure scenes. Our preliminary experiments demonstrate that this method achieves convincing recognition results.

An industrial scale dehydration process for natural gas involving membranes

An industrial scale dehydration process based on hollow fiber membranes for lowering the dew point of natural gas is described in this paper. A pilot test with the feed flux scale of 12x10(4) Nm(3)/d was carried out. Dew points of -8 degreesC-13 degreesC at a gas transport pressure in the pipeline of 4.6M Pa and methane recovery of more than 98% were attained. The water vapor content of the product gas could be maintained around 0.01 vol% during a continuous run of about 700 hours. The effects of feed flux and operation pressure on methane recovery and water vapor content were also investigated. Additionally, some auxiliary technologies, such as a full-time engine using natural gas as fuel and the utilization of vent gas in the process, are also discussed. A small amount of the vent gas from the system was used as a fuel for an engine to drive vacuum pumps, and the heat expelled from the engine was used to warm up the natural gas feed. The whole system can be operated in a self-sustainable manner from an energy point of view, and has a relatively high efficiency in the utilization of natural gas.

Fabrication and testing of a doped lanthanum gallate electrolyte thin-film solid oxide fuel cell

A supported lanthanum gallate (LSGM) electrolyte thin-film solid oxide fuel cell with Ni-YSZ cermet anode and strontium-doped lanthanum manganite (LSM)-yttria stabilized zirconia (YSZ) composite cathode was, for the first time, fabricated and tested. The cell was prepared by an unconventional approach, in which an LSGM thin film (about 15 mum thick) was first deposited on a porous substrate such as a porous YSZ disk by a wet process and sintered at a high temperature (above 1400degrees C). NiO was then incorporated into the porous substrate by a carefully controlled impregnation process and fired at a much lower temperature. In this way, the severe reaction between LSGM and NiO at a high temperature, which is required for the full densification of LSGM film, can be avoided. A strontium-doped LaMnO3 (LSM)-YSZ composite cathode was screen printed on the surface of the LSGM film and then fired at 1250degrees C. The electrolyte resistances of the SOFC single cells fabricated by this approach are much lower compared to those of thick LSGM film supported cells. A maximum output power density of over 0.85 W/cm(2) at 800degreesC with H-2 as fuel and air as oxidant for a fabricated cell was achieved. (C) 2002 The Electrochemical Society.

Distributed Placement of Service Facilities in Large-Scale Networks

The effectiveness of service provisioning in largescale networks is highly dependent on the number and location of service facilities deployed at various hosts. The classical, centralized approach to determining the latter would amount to formulating and solving the uncapacitated k-median (UKM) problem (if the requested number of facilities is fixed), or the uncapacitated facility location (UFL) problem (if the number of facilities is also to be optimized). Clearly, such centralized approaches require knowledge of global topological and demand information, and thus do not scale and are not practical for large networks. The key question posed and answered in this paper is the following: "How can we determine in a distributed and scalable manner the number and location of service facilities?" We propose an innovative approach in which topology and demand information is limited to neighborhoods, or balls of small radius around selected facilities, whereas demand information is captured implicitly for the remaining (remote) clients outside these neighborhoods, by mapping them to clients on the edge of the neighborhood; the ball radius regulates the trade-off between scalability and performance. We develop a scalable, distributed approach that answers our key question through an iterative reoptimization of the location and the number of facilities within such balls. We show that even for small values of the radius (1 or 2), our distributed approach achieves performance under various synthetic and real Internet topologies that is comparable to that of optimal, centralized approaches requiring full topology and demand information.