Engineering Commons^™

Photoionization Of Xenon Clusters, John D. Bozek, Bruce S. Rude, A. L. D. Kilcoyne

United States Department of Energy: Publications

High resolution photoelectron spectra of xenon clusters of about 100 atoms, measured with photon energies of 20 to 60 eV are reported. Peaks due to the clusters are observed at lower binding energies than the corresponding atomic lines and exhibit different behaviors. The peak associated with the Xe 5p_1/2 state at higher binding energy is relatively unchanged with photon energy whereas the Xe 5p_3/2 peak changes its shape with increasing photon energy. The change is attributed to differences in the escape depth of the electrons at different kinetic energies and the bulk and surface components of the cluster.

Pipeline Inspection Technologies Demonstration Report Final

United States Department of Transportation: Publications

The pipeline infrastructure is a critical element in the energy delivery system across the United States. Its failure can affect both public health and safety directly and indirectly through impacts on the energy supply. The pipeline infrastructure is aging, while at the same time Research & Development (R&D) funding from the pipeline industry to develop technologies to assure its integrity is experiencing budgetary constraints. Total R&D funding is being further reduced through the elimination of programs resulting from restructuring within the government and energy industry.

The Pipeline & Hazardous Materials Safety Administration (PHMSA), Pipeline Safety R&D Program mission is to …

Peer Review Report 2006

United States Department of Transportation: Publications

This document is reporting findings from the research peer reviews held February 7-9, 2006 for PHMSA’s Pipeline Safety Research and Development Program. The findings and recommendations in this report derive from the scoring and comments collected from the peer review panelists.

Department of Transportation (DOT) Operating Agencies (OA) are required to begin a systematic process for peer review planning for all influential and highly influential information that the OA plans to disseminate in the “foreseeable” future.

Through the Information Quality Act, Congress directed Office of Management and Budget (OMB) to “provide policy and procedural guidance to Federal agencies for ensuring …

Rd&T Program Overview 2006

United States Department of Transportation: Publications

PHMSA Mission

PHMSA Supports DOT Goals

RD&T Overview

PHMSA RD&T Program Appropriations

Pipeline Safety RD&T

Pipeline Safety RD&T Hierarchy

Systematic RD&T Implementation

Safety

Environment

Hazardous Materials Safety RD&T

Safety -- Global Connectivity -- Environmental Stewardship -- Security: Strategies

Safety -- Global Connectivity -- Environmental Stewardship -- Security: Future Trends and Developments

Safety -- Global Connectivity -- Environmental Stewardship -- Security: Anticipated RD&T Needs

Hazmat Elements & Goals

Hazmat Elements & Possible Products

Hazardous Materials Transportation Cooperative Research Program

PHMSA RD&T Contacts

The Role Of Energy Pipelines And Research In The United States, Cheryl J. Trench, Thomas O. Miesner

United States Department of Transportation: Publications

Energy from oil and natural gas is essential, and will continue to be essential, to all facets of our daily lives. It fuels most of our transportation needs, heats our homes, schools, offices and shops, and even generates a share of our electricity. Oil and natural gas together supply approximately two-thirds of the U.S. energy needs.

Crude oil and natural gas are generally produced in regions located far from consumption centers. This means crude oil must be moved to refineries, and refined products and natural gas must be moved from producing regions to consumption centers.

The U.S. pipeline infrastructure is …

Advanced Welding And Joining Technical Workshop: Pipelines

United States Department of Transportation: Publications

The National Institute of Standards and Technology (NIST) strongly supports the drive toward safer pipelines, and joined with the Pipeline and Hazardous Materials Safety Administration (PHMSA) to advance this goal. NIST in collaboration with PHMSA and several pipeline industry trade organizations, organized and executed the Advanced Welding and Joining Technical Workshop on January 25 and 26, 2006 workshop in Boulder, Colorado.

Assistance in organizing the workshop came from an 18-person steering committee selected to represent the different interests in the pipeline industry. This committee helped to prepare the agenda, identify speakers, organize the working groups, and promote attendance.

The workshop …

Mechanical Damage Workshop & Study Phase 1 Workshop Executive Summary, Michael Baker Jr.

United States Department of Transportation: Publications

Mechanical damage from third party intrusion and latent defects caused during pipeline construction remains a leading cause of major pipeline incidents. Historically, mechanical damage is the single largest cause of failures on pipelines (transporting both natural gas and hazardous liquids).

Significant investments have been made by the Pipeline and Hazardous Materials Safety Administration (PHMSA), the pipeline industry and stakeholder organizations to increase public awareness of the risks of excavation in pipeline corridors. Likewise, much as been invested in research regarding detection of mechanical damage using in-line inspection (ILI) technologies, evaluating the severity of mechanical damage, and mitigation measures. However, no …

Solution Properties Of 1,3-Cyclohexadiene Polymers By Laser Light Scattering And Small-Angle Neutron Scattering, Seok I. Yun, Ken Terao, Kunlun Hong, Yuri B. Melnichenko, George D. Wignall, Jimmy W. Mays, Phillip F. Britt

United States Department of Energy: Publications

1,3-Cyclohexdiene polymers (PCHD) and their derivatives are of interest due to the six-member rings in the main chain, which are expected to impart higher mechanical strength and better thermal and chemical stability, as compared to common vinyl polymers. For example, hydrogenated PCHD has the highest glass transition temperature (t_g ~ 231 °C) of all hydrocarbon polymers, and it also shows good heat, weather, impact, abrasion, and chemical resistance as well as low water absorption. In addition, PCHD has unique photochemical properties, such as excellent transparency, due to the isolated double bonds in the main chain. Also, block copolymers …

Looped Polymer Brushes Formed By Self-Assembly Of Poly(2-Vinylpyridine)-Polystyrene-Poly(2-Vinylpyridine) Triblock Copolymers At The Solid-Fluid Interface. Kinetics Of Preferential Adsorption, Jose Alonzo, Zhenyu Huang, Ming Liu, Jimmy W. Mays, Ryan G. Toomey, Mark D. Dadmun, S. Michael Kilbey, Ii

United States Department of Energy: Publications

The kinetics of assembly of a series of poly(2-vinylpyridine)-polystyrene-poly(2-vinylpyridine) (PVP-b-PS-b-PVP) triblock copolymers from the selective solvent toluene onto a silicon surface has been studied using phase-modulated ellipsometry. The adsorbed amount and thickness have been determined independently as functions of time. Even though the adsorbed amount as a function of time follows the traditional two-step process that is typical of the self-assembly of diblock copolymerssthere is an initial fast adsorption followed by a slow buildup of the layer (brush regime) - the thickness shows an “overshoot” that corresponds to the brush regime. We attribute this phenomenon, not …

Microbial Reduction Of Fe(Iii) In The Fithian And Muloorina Illites: Contrasting Extents And Rates Of Bioreduction, Jennifer L. Seabaugh, Hailiang Dong, Ravi K. Kukkadapu, Dennis D. Eberl, John P. Morton, Jinwook Kim

United States Department of Energy: Publications

Shewanella putrefaciens CN32 reduces Fe(III) within two illites which have different properties: the Fithian bulk fraction and the <0.2 mm fraction of Muloorina. The Fithian illite contained 4.6% (w/w) total Fe, 81% of which was Fe(III). It was dominated by illite with some jarosite (~32% of the total Fe(III)) and goethite (11% of the total Fe(III)). The Muloorina illite was pure and contained 9.2% Fe, 93% of which was Fe(III). Illite suspensions were buffered at pH 7 and were inoculated with CN32 cells with lactate as the electron donor. Select treatments included anthraquinone-2,6-disulfonate (AQDS) as an electron shuttle. Bioproduction of Fe(II) was determined by ferrozine analysis. The unreduced and bioreduced solids were characterized by Mossbauer spectroscopy, X-ray diffraction and transmission electron microscopy. The extent of Fe(III) reduction in the bulk Fithian illite was enhanced by the presence of AQDS (73%) with complete reduction of jarosite and goethite and partial reduction of illite. Mossbauer spectroscopy and chemical extraction determined that 21ÿ25% of illite-associated Fe(III) was bioreduced. The extent of bioreduction was less in the absence of AQDS (63%) and only jarosite was completely reduced with partial reduction of goethite and illite. The XRD and TEM data revealed no significant illite dissolution or biogenic minerals, suggesting that illite was reduced in the solid state and biogenic Fe(II) from jarosite and goethite was either released to aqueous solution or adsorbed onto residual solid surfaces. In contrast, only 1% of the structural Fe(III) in Muloorina illite was bioreduced. The difference in the extent and rate of bioreduction between the two illites was probably due to the difference in layer charge and the total structural Fe content between the Fithian illite (0.56 per formula) and Muloorina illite (0.87). There may be other factors contributing to the observed differences, such as expandability, surface area and the arrangements of Fe in the octahedral sheets. The results of this study have important implications for predicting microbe-induced physical and chemical changes of clay minerals in soils and sediments.

Adsorption Of Uranyl On Gibbsite: A Time-Resolved Laser-Induced Fluorescence Spectroscopy Study, Hyun-Shik Chang, Gregory Korshin, Zheming Wang, John M. Zachara

United States Department of Energy: Publications

Uranyl adsorbed on gibbsite at pH 4.0-8.0 and ionic strengths (ISs) 0.001-0.4 M (NaClO₄) in the absence of carbonate was studied using time-resolved laser-induced fluorescence spectroscopy (TRLIFS) under cryogenic conditions. TRLIFS data showed the presence of several distinct emission components. Their contributions were determined using the evolving factor analysis approach. Four components denoted as species A, B, C, and D were discerned. Each of them was characterized by a characteristic response to pH and IS changes and also by a unique combination of the values of the fundamental transition energyE_0,0, vibronic spacing ∆E, and half-width …

The Dissolution Of Synthetic Na-Boltwoodite In Sodium Carbonate Solutions, Eugene S. Ilton, Chongxuan Liu, Wassana Yantasee, Zheming Wang, Dean A. Moore, Andrew R. Felmy, John M. Zachara

United States Department of Energy: Publications

Uranyl silicates such as uranophane and Na-boltwoodite appear to control the solubility of uranium in certain contaminated sediments at the US Department of Energy Hanford site [Liu, C., Zachara, J.M., Qafoku, O., McKinley, J.P., Heald, S.M., Wang, Z. 2004. Dissolution of uranyl microprecipitates in subsurface sediments at Hanford Site, USA. Geochim. Cosmochim. Acta 68, 4519– 4537.]. Consequently, the solubility of synthetic Na-boltwoodite, Na(UO₂)(SiO₃OH) • 1.5H₂O, was determined over a wide range of bicarbonate concentrations, from circumneutral to alkaline pH, that are representative of porewater and groundwater compositions at the Hanford site and …

C-Type Cytochrome-Dependent Formation Of U(Iv) Nanoparticles By Shewanella Oneidensis, Matthew J. Marshall, Alexander Beliaev, Alice Dohnalkova, David Kennedy, Liang Shi, Zheming Wang, Maxim Boyanov, Barry Lai, Kenneth M. Kemner, Jeffrey Mclean, Samantha Reed, David Culley, Vanessa L. Bailey, Cody Simonson, Daad A. Saffarini, Margaret Romine, John M. Zachara, James K. Fredrickson

United States Department of Energy: Publications

Modern approaches for bioremediation of radionuclide contaminated environments are based on the ability of microorganisms to effectively catalyze changes in the oxidation states of metals that in turn influence their solubility. Although microbial metal reduction has been identified as an effective means for immobilizing highly-soluble uranium(VI) complexes in situ, the biomolecular mechanisms of U(VI) reduction are not well understood. Here, we show that c-type cytochromes of a dissimilatory metal-reducing bacterium, Shewanella oneidensis MR-1, are essential for the reduction of U(VI) and formation of extracelluar UO₂ nanoparticles. In particular, the outer membrane (OM) decaheme cytochrome MtrC (metal reduction), previously implicated …

Oxygen Exposure Promotes Fuel Diversity For Shewanella Oneidensis Microbial Fuel Cells, Justin C. Biffinger, Jacqueline N. Byrd, Breanna L. Dudley, Bradley R. Ringeisen

United States Navy: Publications

Miniature microbial fuel cells (mini-MFCs) were used to monitor the current generated by Shewanella oneidensis DSP10 under both anaerobic and aerobic conditions when exposed to glucose as a potential electron donor. In addition to glucose, other carbon fuels including fructose, sucrose, acetate, and ascorbic acid were also tested. When the anolyte containing S. oneidensis was grown in the presence of oxygen, power densities of 270±10, 350±20, and 120±10 W/m³ were recorded from the mini-MFC for glucose, fructose, and ascorbic acid electron donors, respectively, while sucrose and acetate produced no response. The power produced from glucose decreased considerably (≤100 W/m …

High Power Density From A Miniature Microbial Fuel Cell Using Shewanella Oneidensis Dsp10, Bradley R. Ringeisen, Emily Henderson, Peter K. Wu, Jeremy Pietron, Ricky Ray, Brenda J. Little, Justin C. Biffinger, Joanne M. Jones-Meehan

United States Navy: Publications

A miniature microbial fuel cell (mini-MFC) is described that demonstrates high output power per device crosssection (2.0 cm²) and volume (1.2 cm³). Shewanella oneidensis DSP10 in growth medium with lactate and buffered ferricyanide solutions were used as the anolyte and catholyte, respectively. Maximum power densities of 24 and 10 mW/m² were measured using the true surface areas of reticulated vitreous carbon (RVC) and graphite felt (GF) electrodes without the addition of exogenous mediators in the anolyte. Current densities at maximum power were measured as 44 and 20 mA/m² for RVC and GF, while short …

Evolution Of The Snow Area Index Of The Subarctic Snowpack In Central Alaska Over A Whole Season. Consequences For The Air To Snow Transfer Of Pollutants, A.S. Taillandier, F. Domine, W.R. Simpson, M. Sturm, T.A. Douglas, K Severin

United States Army: Publications

The detailed physical characteristics of the subarctic snowpack must be known to quantify the exchange of adsorbed pollutants between the atmosphere and the snow cover. For the first time, the combined evolutions of specific surface area (SSA), snow stratigraphy, temperature, and density were monitored throughout winter in central Alaska. We define the snow area index (SAI) as the vertically integrated surface area of snow crystals, and this variable is used to quantify pollutants’ adsorption. Intense metamorphism generated by strong temperature gradients formed a thick depth hoar layer with low SSA (90 cm² g^-1) and density (200 kg …

Speciation And Quantitative Mapping Of Metal Species In Microbial Biofilms Using Scanning Transmission X-Ray Microscopy, James J. Dynes, Tolek Tyliszczak, Tohru Araki, John R. Lawrence, George D. W. Swerhone, Gary G. Leppard, Adam P. Hitchcock

United States Department of Energy: Publications

A scanning transmission X-ray microscope illuminated with synchrotron light was used to investigate the speciation and spatial distributions of metals in a microbial biofilm cultivated from river water. Metal 2p absorption edge signals were used to provide metal speciation (through shapes of the absorption spectra) and quantitative spatial distributions of the metal species. This paper presents sample data and describes methods for extracting quantitative maps of metal species from image sequences recorded in the region of the metal 2p edges. Comparisons were made with biochemical characterization of the same region using images recorded at the C 1s and O 1s …

Research Needs In Water Resources And Environment: A Panel Discussion, Otto J. Helweg, Joseph Orlins, Dale Bucks, Regan Murray, David Trueman, Raymond Walton

United States Environmental Protection Agency: Publications

Practicing engineers sometimes criticize researchers for answering questions that no one is asking, or at least for conducting research on questions of personal interest or in areas that funding agencies think are important. Although such research has a place in the overall picture of things, it is instructive to consider the practical issues that engineers in the field face. The fields of water resources and environment are very broad, and only a small number of research users could be included on the panel seated by the Education and Research Council at the 2004 World Water and Environmental Resources Congress. One …

Design And Evaluation Of Packet Classification Systems, Doctoral Dissertation, December 2006, Haoyu Song

All Computer Science and Engineering Research

Although many algorithms and architectures have been proposed, the design of efficient packet classification systems remains a challenging problem. The diversity of filter specifications, the scale of filter sets, and the throughput requirements of high speed networks all contribute to the difficulty. We need to review the algorithms from a high-level point-of-view in order to advance the study. This level of understanding can lead to significant performance improvements. In this dissertation, we evaluate several existing algorithms and present several new algorithms as well. The previous evaluation results for existing algorithms are not convincing because they have not been done in …

Hail: An Algorithm For The Hardware Accelerated Identification Of Languages, Master's Thesis, May 2006, Charles M. Kastner

All Computer Science and Engineering Research

This thesis examines in detail the Hardware-Accelerated Identification of Languages (HAIL) project. The goal of HAIL is to provide an accurate means to identify the language and encoding used in streaming content, such as documents passed over a high-speed network. HAIL has been implemented on the Field-programmable Port eXtender (FPX), an open hardware platform developed at Washington University in St. Louis. HAIL can accurately identify the primary languages and encodings used in text at rates much higher than what can be achieved by software algorithms running on microprocessors.

A Query-Centric Approach To Supporting The Development Of Context-Aware Applications For Mobile Ad Hoc Networks, Doctoral Dissertation, August 2006, Jamie Payton

All Computer Science and Engineering Research

The wide-spread use of mobile computing devices has led to an increased demand for applications that operate dependably in opportunistically formed networks. A promising approach to supporting software development for such dynamic settings is to rely on the context-aware computing paradigm, in which an application views the state of the surrounding ad hoc network as a valuable source of contextual information that can be used to adapt its behavior. Collecting context information distributed across a constantly changing network remains a significant technical challenge. This dissertation presents a query-centered approach to simplifying context interactions in mobile ad hoc networks. Using such …

Unified Power Management In Wireless Sensor Networks, Doctoral Dissertation, August 2006, Guoliang Xing

All Computer Science and Engineering Research

Radio power management is of paramount concern in wireless sensor networks (WSNs) that must achieve long lifetimes on scarce amount of energy. Previous work has treated communication and sensing separately, which is insufficient for a common class of sensor networks that must satisfy both sensing and communication requirements. Furthermore, previous approaches focused on reducing energy consumption in individual radio states resulting in suboptimal solutions. Finally, existing power management protocols often assume simplistic models that cannot accurately reflect the sensing and communication properties of real-world WSNs. We develop a unified power management approach to address these issues. We first analyze the …

Competent Program Evolution, Doctoral Dissertation, December 2006, Moshe Looks

All Computer Science and Engineering Research

Heuristic optimization methods are adaptive when they sample problem solutions based on knowledge of the search space gathered from past sampling. Recently, competent evolutionary optimization methods have been developed that adapt via probabilistic modeling of the search space. However, their effectiveness requires the existence of a compact problem decomposition in terms of prespecified solution parameters. How can we use these techniques to effectively and reliably solve program learning problems, given that program spaces will rarely have compact decompositions? One method is to manually build a problem-specific representation that is more tractable than the general space. But can this process be …

Limit Crossing For Decision Problems, Sharlee Climer, Weixiong Zhang

All Computer Science and Engineering Research

Limit crossing is a methodology in which modified versions of a problem are solved and compared, yielding useful information about the original problem. Pruning rules that are used to exclude portions of search trees are excellent examples of the limit-crossing technique. In our previous work, we examined limit crossing for optimization problems. In this paper, we extend this methodology to decision problems. We demonstrate the use of limit crossing in our design of a tool for identifying K-SAT backbones. This tool is guaranteed to identify all of the backbone variables by solving at most n+1 formulae, where n is the …

A Proposed Architecture For The Geni Backbone Platform, Jonathan Turner

All Computer Science and Engineering Research

The GENI Project (Global Environment for Network Innovation) is a major NSF-sponsored initiative that seeks to create a national research facility to enable experimental deployment of innovative new network architectures on a sufficient scale to enable realistic evaluation. One key component of the GENI system will be the GENI Backbone Platform (GBP) that provides the resources needed to allow multiple experimental networks to co-exist within the shared GENI infrastructure. This report reviews the objectives for the GBP, reviews the key issues that affect its design and develops a detailed reference architecture in order to provide a concrete example for how …

The Real Effect Of Warm-Cool Colors, Reynold J. Bailey, Cindy M, Grimm, Chris Davoli

All Computer Science and Engineering Research

The phenomenon of warmer colors appearing nearer in depth to viewers than cooler colors has been studied extensively by psychologists and other vision researchers. The vast majority of these studies have asked human observers to view physically equidistant, colored stimuli and compare them for relative depth. However, in most cases, the stimuli presented were rather simple: straight colored lines, uniform color patches, point light sources, or symmetrical objects with uniform shading. Additionally, the colors used were typically highly saturated. Although such stimuli are useful in isolating and studying depth cues in certain contexts, they leave open the question of whether …

Tuple Space Coordination Across Space & Time, Gruia-Catalin Roman, Radu Handorean, Chenyang Lu

All Computer Science and Engineering Research

CAST is a coordination model designed to support interactions among agents executing on hosts that make up a mobile ad hoc network (MANET). From an application programmer’s point of view, CAST makes it possible for operations to be executed at arbitrary locations in space, at prescribed times which may be in the future, and on remote hosts even when no end-to-end connected route exists between the initiator and target(s) of the operation. To accomplish this, CAST assumes that each host moves in space in accordance with a motion profile which is accurate but which at any given time extends into …

Fair Efficiency, Or Low Average Delay Without Starvation, Christoph Jechlitschek, Sergey Gorinksky

All Computer Science and Engineering Research

Elastic applications are primarily interested in minimal delay achievable for their messages under current network load. In this paper, we investigate how to transmit such messages over a bottleneck link efficiently and fairly.

Virtualizing Network Processors, Ben Wun, Jonathan Turner, Patrick Crowley

All Computer Science and Engineering Research

This paper considers the problem of virtualizing the resources of a network processor (NP) in order to allow multiple third-parties to execute their own virtual router software on a single physical router at the same time. Our broad interest is in designing such a router capable of supporting virtual networking. We discuss the issues and challenges involved in this virtualization, and then describe specific techniques for virtualizing both the control and data-plane processors on NPs. For Intel IXP NPs in particular, we present a dynamic, macro-based technique for virtualization that allows multiple virtual routers to run on multiple data plane …

An Improved Analysis For A Greedy Remote-Clique Algorithm Using Factor-Revealing Lps, Benjamin E. Birnbaum, Kenneth J. Goldman

All Computer Science and Engineering Research

Given a complete graph with nonnegative edge weights satisfying the triangle inequality and a positive integer p, the remote-clique problem is to find a subset of p vertices having a maximum-weight induced subgraph. A simple greedy algorithm for the problem has been shown to have an approximation ratio of 4, but a tight example has not been provided. In this paper, we use the technique of factor revealing linear programs to prove that this algorithm actually achieves an approximation ratio of 2, matching the best-known ratio for the problem. The greedy algorithm's running time of O(pn) makes it the fastest …