We use eight different observational datasets to estimate California-average temperature trends over 1950-1999. Observed results are compared to trends from a suite of control simulations of natural internal climate variability. Observed increases in annual-mean surface temperature are distinguishable from climate noise in some but not all observational datasets. The most robust results are large positive trends in mean and maximum daily temperatures in late winter/early spring, as well as increases in minimum daily temperatures from January to September. These trends are inconsistent with model-based estimates of natural internal climate variability, and thus require one or more external forcing agents to be explained. Our results suggest that the warming of Californian winters over the second half of the twentieth century is associated with human-induced changes in large-scale atmospheric circulation. We also hypothesize that the lack of a detectable increase in summertime maximum temperature arises from a cooling associated with large-scale irrigation. This cooling may have, until now, counteracted the warming induced by increasing greenhouse gases and urbanization effects.

A fracture within a porous background is modeled as a thin porous layer with increased compliance and finite permeability. For small layer thickness, a set of boundary conditions can be derived that relate particle velocity and stress across a fracture, induced by incident poroelastic waves. These boundary conditions are given via phenomenological parameters that can be used to examine and characterize the seismic response of a fracture. One of these parameters, here it is called membrane permeability, is shown through several examples to control the scattering amplitude of the slow P waves for very low-permeability fractures, which in turn controls the intrinsic attenuation of the waves.

The ion beam deposition of (NbTa)2O5 has been investigated for realizing high reflectance multilayer stacks of high damage threshold for applications in the engineering of dielectric gratings for use at 800 nm. Deposition conditions were optimized to yield fully oxidized films as determined from x-ray photoelectron spectroscopy (XPS). The film properties were also investigated using spectroscopic ellipsometry, and spectrophotometry to determine their refractive index and thickness respectively. Damage threshold testing was performed on single films using an amplified Ti:Sapphire laser producing a train of 170 ps pulses at a wavelength of 800 nm with an average energy of 100 mJ. The laser output was focused at the surface of the samples via a 0.5 m focal length lens to generate fluences ranging from 0 to 9 J/cm{sup 2}. At the optimum deposition conditions for highest optical quality and damage threshold, high reflector stacks of (NbTa){sub 2}O{sub 5}/SiO2 were fabricated. These stacks were employed to fabricate dielectric gratings with 1740 l/mm for use with 800 nm light. At an input angle of 8{sup o} from Littrow and a wavelength from 770 to 830 nm, >90% diffraction efficiency is achieved, with peak diffraction efficiency of >97%. The demonstration of dielectric gratings at …

In this work, we propose a computationally feasible approachtodetect severe multiple contingencies. We pose a contingency analysisproblem using a nonlinear optimization framework, which enables ustodetect the fewest possible transmission line outages resulting ina systemfailure of specified severity, and the most severe system failure causedby removing a specified number of transmission lines from service.Illustrations using a three bus system and the IEEE ~;30 bus system aimto exhibit the effectiveness of the proposed approach.

Large-Mach-number parallel plasma flows in the single-null SOL of different tokamaks are simulated with multi-fluid transport code UEDGE. The key role of poloidal asymmetry of cross-field plasma transport as the driving mechanism for such flows is discussed. The impact of ballooning-like diffusive and convective transport and plasma flows on divertor detachment, material migration, impurity flows, and erosion/deposition profiles is studied. The results on well-balanced double null plasma modeling that are indicative of strong asymmetry of cross-field transport are presented.

Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, they show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

In the first part of the talk, I explain what empirical evidence points to the need for having an effective grand unification-like symmetry possessing the symmetry SU(4)-color in 4D. If one assumes the premises of a future predictive theory including gravity--be it string/M theory or a reincarnation--this evidence then suggests that such a theory should lead to an effective grand unification-like symmetry as above in 4D, near the string-GUT-scale, rather than the standard model symmetry. Advantages of an effective supersymmetric G(224) = SU(2){sub L} x SU(2){sub R} x SU(4){sup c} or SO(10) symmetry in 4D in explaining (1) observed neutrino oscillations, (2) baryogenesis via leptogenesis, and (3) certain fermion mass-relations are noted. And certain distinguishing tests of a SUSY G(224) or SO(10)-framework involving CP and flavor violations (as in {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma}, edm's of the neutron and the electron) as well as proton decay are briefly mentioned. Recalling some of the successes we have had in our understanding of nature so far, and the current difficulties of string/M theory as regards the large multiplicity of string vacua, some comments are made on the traditional goal of understanding vis a vis the recently evolved view of landscape and …

Poster for WindPower 2006 held June 4-7, 2006, in Pittsburgh, PA, describing the 225-kW dynamometer for testing small wind turbine components.

This report is on Cellulases and Cellulosomes on Gordon Research Conferences.

Human exposure assessment is a key step in estimating the environmental and public health burdens that result chemical emissions in the life cycle of an industrial product or service. This column presents the third in a series of overviews of the state of the art in integrated environmental assessment - earlier columns described emissions estimation (Frey and Small, 2003) and fate and transport modeling (Ramaswami, et al., 2004). When combined, these first two assessment elements provide estimates of ambient concentrations in the environment. Here we discuss how both models and measurements are used to translate ambient concentrations into metrics of human and ecological exposure, the necessary precursors to impact assessment. Exposure assessment is the process of measuring and/or modeling the magnitude, frequency and duration of contact between a potentially harmful agent and a target population, including the size and characteristics of that population (IPCS, 2001; Zartarian, et al., 2005). Ideally the exposure assessment process should characterize the sources, routes, pathways, and uncertainties in the assessment. Route of exposure refers to the way that an agent enters the receptor during an exposure event. Humans contact pollutants through three routes--inhalation, ingestion, and dermal uptake. Inhalation occurs in both outdoor environments and indoor …

This paper investigates how critical-peak pricing (CPP)affects households with different usage and income levels, with the goalof informing policy makers who are considering the implementation of CPPtariffs in the residential sector. Using a subset of data from theCalifornia Statewide Pricing Pilot of 2003-2004, average load changeduring summer events, annual percent bill change, and post-experimentsatisfaction ratings are calculated across six customer segments,categorized by historical usage and income levels. Findings show thathigh-use customers respond significantly more in kW reduction than dolow-use customers, while low-use customers save significantly more inpercentage reduction of annual electricity bills than do high-usecustomers results that challenge the strategy of targeting only high-usecustomers for CPP tariffs. Across income levels, average load and billchanges were statistically indistinguishable, as were satisfaction ratesresults that are compatible with a strategy of full-scale implementationof CPP rates in the residential sector. Finally, the high-use customersearning less than $50,000 annually were the most likely of the groups tosee bill increases about 5 percent saw bill increases of 10 percent ormore suggesting that any residential CPP implementation might considertargeting this customer group for increased energy efficiencyefforts.

Double-shell (DS) targets (Amendt, P. A. et al., 2002) offer a complementary approach to the cryogenic baseline design (Lindl, J. et al., 2004) for achieving ignition on the National Ignition Facility (NIF). Among the expected benefits are the ease of room temperature preparation and fielding, the potential for lower laser backscatter and the reduced need for careful shock timing. These benefits are offset, however, by demanding fabrication tolerances, e.g., shell concentricity and shell surface smoothness. In particular, the latter is of paramount importance since DS targets are susceptible to the growth of interface perturbations from impulsive and time-dependent accelerations. Previous work (Milovich, J. L. et al., 2004) has indicated that the growth of perturbations on the outer surface of the inner shell is potentially disruptive. To control this instability new designs have been proposed requiring bimetallic inner shells and material-matching mid-Z nanoporous foam. The challenges in manufacturing such exotic foams have led to a further evaluation of the densities and pore sizes needed to reduce the seeding of perturbations on the outer surface of the inner shell, thereby guiding the ongoing material science research efforts. Highly-resolved 2D simulations of porous foams have been performed to establish an upper limit on …

The world is at a turning point, moving away from the Cold War nuclear legacy towards a future global nuclear enterprise; and this presents a transformational challenge for nuclear materials management. Achieving safety and security during this transition is complicated by the diversified spectrum of threat 'players' that has greatly impacted nonproliferation, counterterrorism, and homeland security requirements. Rogue states and non-state actors no longer need self-contained national nuclear expertise, materials, and equipment due to availability from various sources in the nuclear market, thereby reducing the time, effort and cost for acquiring a nuclear weapon (i.e., manifestations of latency). The terrorist threat has changed the nature of military and national security requirements to protect these materials. An Integrated Global Nuclear Materials Management (IGNMM) approach would address the existing legacy nuclear materials and the evolution towards a nuclear energy future, while strengthening a regime to prevent nuclear weapon proliferation. In this paper, some preliminary concepts and studies of IGNMM will be presented. A systematic analysis of nuclear materials, activities, and controls can lead to a tractable, integrated global nuclear materials management architecture that can help remediate the past and manage the future. A systems approach is best suited to achieve multi-dimensional and …

We are developing ALE3D models to describe the thermal, chemical and mechanical behavior during the heating, ignition and explosive phases of various cookoff phenomena. The candidate models and numerical strategies are being evaluated using benchmark cookoff experiments. ALE3D is a three-dimensional computer code capable of solving the model equations in a coupled fashion through all the phases of the cookoff in a single calculation. For the cookoff experiments, we are interested in representing behavior on widely varying timescales. We have used an implicit hydrodynamics option during the heating phase and an explicit solution method during the explosive phase. To complicate the modeling problem, high heat fluxes cause rapid temperature increases in boundary layers and lead to the formation of gaps between energetic and structural materials and ignition on surfaces. The initially solid energetic and structural materials react to produce gases, which fill the gaps. These materials can also melt and flow. Since an implicit solution method is used, simple no-strength materials models can no longer be used for liquids and gases. In this paper, we discuss and demonstrate choices of materials models for solid/liquid/gas mixtures to be used in conjunction with the implicit solution method. In addition, results are given …

The main advantage of inverse iteration over the QR algorithm and Divide & Conquer for the symmetric tridiagonal eigenproblem is that subsets of eigenpairs can be computed at reduced cost. The MRRR algorithm (MRRR = Multiple Relatively Robust Representations) is a clever variant of inverse iteration without the need for reorthogonalization. STEGR, the current version of MRRR in LAPACK 3.0, does not allow for subset computations. The next release of STEGR is designed to compute a (sub-)set of k eigenpairs with {Omicron}(kn) operations. Because of the special way in which eigenvectors are computed, MRRR subset computations are more complicated than when using inverse iteration. Unlike the latter, MRRR sometimes cannot ignore the unwanted part of the spectrum. We describe the problems with what we call 'false singletons'. These are eigenvalues that appear to be isolated with respect to the wanted eigenvalues but in fact belong to a tight cluster of unwanted eigenvalues. This paper analyzes these complications and ways to deal with them.

In this commentary, we advocate building a richer set of descriptions about our invaluable and exponentially growing collection of genomes and metagenomic datasets through the construction of consensus-driven data capture and exchange mechanisms. Standardization activities must proceed within the auspices of open-access and international working bodies, and to tackle the issues surrounding the development of better descriptions of genomic investigations we have formed the Genomic Standards Consortium (GSC). Here, we introduce the 'Minimum Information about a Genome Sequence' specification in the hopes of gaining wider participation in its development and discuss the resources that will be required to support it (standardization of annotations through the use of ontologies and mechanisms of metadata capture, exchange). As part of its wider goals, the GSC also strongly supports improving the 'transparency' of the information contained in existing genomic databases that contain calculated analyses and genomic annotations.

Density functional theory (DFT), in conjunction with the fixed-spin-moment (FSM) method, spin-orbit coupling (SO), and orbital polarization (OP), is shown to retain key features of the conventional DFT treatment of {delta}-Pu while at the same time not producing the substantial net magnetic moments commonly predicted by this theory. It is shown that when a small adjustment of the spin moment (less than 20%) is allowed, a complete spin- and orbital-moment cancellation occurs which results in a zero net magnetic moment in {delta}-Pu. This minor modification, accomplished by the FSM method, is shown to have a very small effect on the calculated total energy as well as the electron density-of-states (DOS). The photoemission spectra (PES), obtained from the DOS of the present model, compares equal or better to measured spectra, than that of two other recent non-magnetic models for {delta}-Pu.

This work is motivated by the growing interest in injectingcarbon dioxide into deep geological formations as a means of avoidingatmospheric emissions of carbon dioxide and consequent global warming.One of the key questions regarding the feasibility of this technology isthe potential rate of leakage out of the primary storage formation. Weseek exact solutions in a model of gas flow driven by a combination ofbuoyancy, viscous and capillary forces. Different combinations of theseforces and characteristic length scales of the processes lead todifferent time scaling and different types of solutions. In the case of athin, tight seal, where the impact of gravity is negligible relative tocapillary and viscous forces, a Ryzhik-type solution implies square-rootof time scaling of plume propagation velocity. In the general case, a gasplume has two stable zones, which can be described by travelling-wavesolutions. The theoretical maximum of the velocity of plume migrationprovides a conservative estimate for the time of vertical migration.Although the top of the plume has low gas saturation, it propagates witha velocity close to the theoretical maximum. The bottom of the plumeflows significantly more slowly at a higher gas saturation. Due to localheterogeneities, the plume can break into parts. Individual plumes alsocan coalesce and from larger plumes. The …

The US LHC Accelerator Research Program (LARP) consists of four US laboratories (BNL, FNAL, LBNL, and SLAC) collaborating with CERN to achieve a successful commissioning of the LHC and to develop the next generation of Interaction Region magnets. In 2004, a large aperture Nb{sub 3}Sn racetrack quadrupole magnet (SQ01) has been fabricated and tested at LBNL. The magnet utilized four subscale racetrack coils and was instrumented with strain gauges on the support structure and directly over the coil's turns. SQ01 exhibited training quenches in two of the four coils and reached a peak field in the conductor of 10.4 T at a current of 10.6 kA. After the test, the magnet was disassembled, inspected with pressure indicating films, and reassembled with minor modifications. A second test (SQ01b) was performed at FNAL and included training studies, strain gauge measurements and magnetic measurements. Magnet inspection, test results, and magnetic measurements are reported and discussed, and a comparison between strain gauge measurements and 3D finite element computations is presented

The development of test plans to validate the CERTSMicrogrid concept is discussed, including the status of a testbed.Increased application of Distributed Energy Resources on the Distributionsystem has the potential to improve performance, lower operational costsand create value. Microgrids have the potential to deliver these highvalue benefits. This presentation will focus on operationalcharacteristics of the CERTS microgrid, the partners in the project andthe status of the CEC/CERTS microgrid testbed. Index Terms DistributedGeneration, Distributed Resource, Islanding, Microgrid,Microturbine

A novel exon microarray format that probes gene expression with single exon resolution was employed to elucidate critical features of a vertebrate muscle alternative splicing program. A dataset of 56 microarray-defined, muscle-enriched exons and their flanking introns were examined computationally in order to investigate coordination of the muscle splicing program. Candidate intron regulatory motifs were required to meet several stringent criteria: significant over-representation near muscle-enriched exons, correlation with muscle expression, and phylogenetic conservation among genomes of several vertebrate orders. Three classes of regulatory motifs were identified in the proximal downstream intron, within 200nt of the target exons: UGCAUG, a specific binding site for Fox-1 related splicing factors; ACUAAC, a novel branchpoint-like element; and UG-/UGC-rich elements characteristic of binding sites for CELF splicing factors. UGCAUG was remarkably enriched, being present in nearly one-half of all cases. These studies suggest that Fox and CELF splicing factors play a major role in enforcing the muscle-specific alternative splicing program, facilitating expression of a set of unique isoforms of cytoskeletal proteins that are critical to muscle cell differentiation. Supplementary materials: There are four supplementary tables and one supplementary figure. The tables provide additional detailed information concerning the muscle-enriched datasets, and about over-represented oligonucleotide sequences in …

The US LHC Accelerator Research Program (LARP) is developing Nb{sub 3}Sn accelerator magnet technology for the LHC luminosity upgrade. Two 90 mm 'Technology Quadrupole' models (TQS01, TQC01) are being developed in close collaboration between LBNL and FNAL, using identical coil design, but two different support structures. The TQS01 structure was developed and tested at LBNL. With this approach coils are supported by an outer aluminum shell and assembled using keys and bladders. In contrast, the second model TQC01, utilize stainless steel collars and a thick stainless steel skin. This paper describes the TQS01 model magnet, its 3D ANSYS stress analysis, and anticipated instrumentation and assembly procedure.

Ge Blocked Impurity Band (BIB) photoconductors have the potential to replace stressed Ge:Ga photoconductors for far-infrared astronomical observations. A novel planar BIB device has been fabricated in which ion-implanted boron is used to form the blocking and absorbing layers of necessary purity and compensation. The effect of doping in the infrared active layer on the far-infrared photoconductive response has been studied, and the optimum doping concentration is found to be {approx} 4 x 10{sup 16} cm{sup -3}. Devices doped near this concentration show good blocking characteristics with low dark currents. The spectral response extends to {approx} 45 cm{sup -1}, clearly showing the formation of an impurity band. Under low background testing conditions these devices attain a responsivity of 0.12 A/W and NEP of 5.23 x 10{sup -15} W/Hz{sup -1/2}.

The accurate detection and removal of insect clutter from millimeter wavelength cloud radar (MMCR) returns is of high importance to boundary layer cloud research (e.g., Geerts et al., 2005). When only radar Doppler moments are available, it is difficult to produce a reliable screening of insect clutter from cloud returns because their distributions overlap. Hence, screening of MMCR insect clutter has historically involved a laborious manual process of cross-referencing radar moments against measurements from other collocated instruments, such as lidar. Our study looks beyond traditional radar moments to ask whether analysis of recorded Doppler spectra can serve as the basis for reliable, automatic insect clutter screening. We focus on the MMCR operated by the Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) program at its Southern Great Plains (SGP) facility in Oklahoma. Here, archiving of full Doppler spectra began in September 2003, and during the warmer months, a pronounced insect presence regularly introduces clutter into boundary layer returns.