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Sample records for aligned tight gas

  1. Structurally controlled and aligned tight gas reservoir compartmentalization in the San Juan and Piceance Basins

    Energy Technology Data Exchange (ETDEWEB)

    Decker, A.D.; Kuuskraa, V.A.; Klawitter, A.L.

    1995-10-01

    Recurrent basement faulting is the primary controlling mechanism for aligning and compartmentalizing upper Cretaceous aged tight gas reservoirs of the San Juan and Piceance Basins. Northwest trending structural lineaments that formed in conjunction with the Uncompahgre Highlands have profoundly influenced sedimentation trends and created boundaries for gas migration; sealing and compartmentalizing sedimentary packages in both basins. Fractures which formed over the structural lineaments provide permeability pathways which allowing gas recovery from otherwise tight gas reservoirs. Structural alignments and associated reservoir compartments have been accurately targeted by integrating advanced remote sensing imagery, high resolution aeromagnetics, seismic interpretation, stratigraphic mapping and dynamic structural modelling. This unifying methodology is a powerful tool for exploration geologists and is also a systematic approach to tight gas resource assessment in frontier basins.

  2. Naturally fractured tight gas reservoir detection optimization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-01

    Building upon the partitioning of the Greater Green River Basin (GGRB) that was conducted last quarter, the goal of the work this quarter has been to conclude evaluation of the Stratos well and the prototypical Green River Deep partition, and perform the fill resource evaluation of the Upper Cretaceous tight gas play, with the goal of defining target areas of enhanced natural fracturing. The work plan for the quarter of November 1-December 31, 1998 comprised four tasks: (1) Evaluation of the Green River Deep partition and the Stratos well and examination of potential opportunity for expanding the use of E and P technology to low permeability, naturally fractured gas reservoirs, (2) Gas field studies, and (3) Resource analysis of the balance of the partitions.

  3. Naturally fractured tight gas reservoir detection optimization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-30

    The work plan for October 1, 1997 to September 30, 1998 consisted of investigation of a number of topical areas. These topical areas were reported in four quarterly status reports, which were submitted to DOE earlier. These topical areas are reviewed in this volume. The topical areas covered during the year were: (1) Development of preliminary tests of a production method for determining areas of natural fracturing. Advanced Resources has demonstrated that such a relationship exists in the southern Piceance basin tight gas play. Natural fracture clusters are genetically related to stress concentrations (also called stress perturbations) associated with local deformation such a faulting. The mechanical explanation of this phenomenon is that deformation generally initiates at regions where the local stress field is elevated beyond the regional. (2) Regional structural and geologic analysis of the Greater Green River Basin (GGRB). Application of techniques developed and demonstrated during earlier phases of the project for sweet-spot delineation were demonstrated in a relatively new and underexplored play: tight gas from continuous-typeUpper Cretaceous reservoirs of the Greater Green River Basin (GGRB). The effort included data acquisition/processing, base map generation, geophysical and remote sensing analysis and the integration of these data and analyses. (3) Examination of the Table Rock field area in the northern Washakie Basin of the Greater Green River Basin. This effort was performed in support of Union Pacific Resources- and DOE-planned horizontal drilling efforts. The effort comprised acquisition of necessary seismic data and depth-conversion, mapping of major fault geometry, and analysis of displacement vectors, and the development of the natural fracture prediction. (4) Greater Green River Basin Partitioning. Building on fundamental fracture characterization work and prior work performed under this contract, namely structural analysis using satellite and

  4. US production of natural gas from tight reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-18

    For the purposes of this report, tight gas reservoirs are defined as those that meet the Federal Energy Regulatory Commission`s (FERC) definition of tight. They are generally characterized by an average reservoir rock permeability to gas of 0.1 millidarcy or less and, absent artificial stimulation of production, by production rates that do not exceed 5 barrels of oil per day and certain specified daily volumes of gas which increase with the depth of the reservoir. All of the statistics presented in this report pertain to wells that have been classified, from 1978 through 1991, as tight according to the FERC; i.e., they are ``legally tight`` reservoirs. Additional production from ``geologically tight`` reservoirs that have not been classified tight according to the FERC rules has been excluded. This category includes all producing wells drilled into legally designated tight gas reservoirs prior to 1978 and all producing wells drilled into physically tight gas reservoirs that have not been designated legally tight. Therefore, all gas production referenced herein is eligible for the Section 29 tax credit. Although the qualification period for the credit expired at the end of 1992, wells that were spudded (began to be drilled) between 1978 and May 1988, and from November 5, 1990, through year end 1992, are eligible for the tax credit for a subsequent period of 10 years. This report updates the EIA`s tight gas production information through 1991 and considers further the history and effect on tight gas production of the Federal Government`s regulatory and tax policy actions. It also provides some high points of the geologic background needed to understand the nature and location of low-permeability reservoirs.

  5. Western tight gas sands advanced logging workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, J B; Carroll, Jr, H B [eds.

    1982-04-01

    An advanced logging research program is one major aspect of the Western Tight Sands Program. Purpose of this workshop is to help BETC define critical logging needs for tight gas sands and to allow free interchange of ideas on all aspects of the current logging research program. Sixteen papers and abstracts are included together with discussions. Separate abstracts have been prepared for the 12 papers. (DLC)

  6. Subminiature fission chamber with gas tight penetration

    International Nuclear Information System (INIS)

    Fission chambers suffer from gas leaks at electric feed-trough. This micro chamber suppresses that defect thanks to an alumina plug and welded seal of the chamber sleeve. This device is easy to produce at industrial scale with reduced dimensions (1,5 mm diameter, 25 mm length). It can work with 30 m long feeding cables. (D.L.). 3 figs

  7. Naturally fractured tight gas reservoir detection optimization. Quarterly report, January--March 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This report describes progress in the following five projects: (1) Geologic assessment of the Piceance Basin; (2) Regional stratigraphic studies, Upper Cretaceous Mesaverde Group, southern Piceance Basin, Colorado; (3) Structurally controlled and aligned tight gas reservoir compartmentalization in the San Juan and Piceance Basins--Foundation for a new approach to exploration and resource assessments of continuous type deposits; (4) Delineation of Piceance Basin basement structures using multiple source data--Implications for fractured reservoir exploration; and (5) Gas and water-saturated conditions in the Piceance Basin, western Colorado--Implications for fractured reservoir detection in a gas-centered coal basin.

  8. Advanced Hydraulic Fracturing Technology for Unconventional Tight Gas Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Holditch; A. Daniel Hill; D. Zhu

    2007-06-19

    The objectives of this project are to develop and test new techniques for creating extensive, conductive hydraulic fractures in unconventional tight gas reservoirs by statistically assessing the productivity achieved in hundreds of field treatments with a variety of current fracturing practices ranging from 'water fracs' to conventional gel fracture treatments; by laboratory measurements of the conductivity created with high rate proppant fracturing using an entirely new conductivity test - the 'dynamic fracture conductivity test'; and by developing design models to implement the optimal fracture treatments determined from the field assessment and the laboratory measurements. One of the tasks of this project is to create an 'advisor' or expert system for completion, production and stimulation of tight gas reservoirs. A central part of this study is an extensive survey of the productivity of hundreds of tight gas wells that have been hydraulically fractured. We have been doing an extensive literature search of the SPE eLibrary, DOE, Gas Technology Institute (GTI), Bureau of Economic Geology and IHS Energy, for publicly available technical reports about procedures of drilling, completion and production of the tight gas wells. We have downloaded numerous papers and read and summarized the information to build a database that will contain field treatment data, organized by geographic location, and hydraulic fracture treatment design data, organized by the treatment type. We have conducted experimental study on 'dynamic fracture conductivity' created when proppant slurries are pumped into hydraulic fractures in tight gas sands. Unlike conventional fracture conductivity tests in which proppant is loaded into the fracture artificially; we pump proppant/frac fluid slurries into a fracture cell, dynamically placing the proppant just as it occurs in the field. From such tests, we expect to gain new insights into some of the critical

  9. Gas transport in tight porous media Gas kinetic approach

    DEFF Research Database (Denmark)

    Shapiro, Alexander; Wesselingh, Johannes

    2008-01-01

    We describe the flow of gas in a porous medium in the kinetic regime, where the viscous flow structure is not formed in separate pores. Special attention is paid to the dense kinetic regime, where the interactions within the gas are as important as the interaction with the porous medium. The tran....... The role of the thermal gradient in the transport law is clarified. (c) 2007 Elsevier B.V. All rights reserved....

  10. Quantifying tight-gas sandstone permeability via critical path analysis

    Science.gov (United States)

    Ghanbarian, Behzad; Torres-Verdín, Carlos; Skaggs, Todd H.

    2016-06-01

    Rock permeability has been actively investigated over the past several decades by the geosciences community. However, its accurate estimation still presents significant technical challenges, particularly in spatially complex rocks. In this short communication, we apply critical path analysis (CPA) to estimate permeability in porous rocks from measured mercury intrusion porosimetry and electrical conductivity data. Theoretical estimations of various CPA-based models are then compared to experimental measurements using eighteen tight-gas sandstones. Except for two of the samples, we find permeability estimations performed with the Skaggs model (assuming pore diameter independent of its length) more accurate than other models, within a factor of two of the measured permeabilities. We discuss some plausible sources of the uncertainties.

  11. Assessment of unconventional tight-gas resources of the Magallanes Basin Province, Chile, 2015

    Science.gov (United States)

    Schenk, Christopher J.; Charpentier, Ronald R.; Pitman, Janet K.; Tennyson, Marilyn E.; Brownfield, Michael E.; Gaswirth, Stephanie B.; Le, Phuong A.; Leathers-Miller, Heidi M.; Marra, Kristen R.

    2016-01-20

    Using a geology-based assessment methodology, the U.S. Geological Survey assessed a technically recoverable mean resource of 8.3 trillion cubic feet of unconventional tight gas in the Zona Glauconitica of the Magallanes Basin Province, Chile.

  12. Assessment of tight-gas resources in Canyon sandstones of the Val Verde Basin, Texas, 2016

    Science.gov (United States)

    Schenk, Christopher J.; Tennyson, Marilyn E.; Klett, Timothy R.; Mercier, Tracey J.; Brownfield, Michael E.; Gaswirth, Stephanie B.; Hawkins, Sarah J.; Leathers-Miller, Heidi M.; Marra, Kristen R.; Finn, Thomas M.; Pitman, Janet K.

    2016-07-08

    Using a geology-based assessment methodology, the U.S. Geological Survey assessed mean resources of 5 trillion cubic feet of gas and 187 million barrels of natural gas liquids in tight-gas assessment units in the Canyon sandstones of the Val Verde Basin, Texas.

  13. The age of unconventional gas: tight gas reservoirs; the potential economic impact and local industry reality check

    International Nuclear Information System (INIS)

    With the decline of production and increase in demand of fossil-fuel, economically producing gas from unconventional sources is a great challenge today. The large volume and long-term potential, attractive gas prices and unprecedented interest in world markets, brings the unconventional gas into the forefront of our energy future. An unconventional reservoir is one that cannot be produced as economic flow rates or that does not produce economic volumes of oil and gas without assistance from massive simulation treatments or special recovery processes and technologies, such as steam injection. Typical unconventional reservoirs are tight-gas sands, coal-bed methane, heavy oil and gas shales. Law and Curtis (2002) defined low-permeability (tight) reservoirs as having permeabilities less than 0.1 milidarcies. With a dimming possibility of economically viable alternative sources of energy in near future, ever widening gap between the energy demand and supply and the decline of production of conventional fossil-fuel, the thrust on unconventional sources of gas (tight Gas etc) is glowingly increasing world-over. With the successful marketing of natural gas as an environmentally-friendly fuel, demand of gas has increased sharply in the opening years of the 21st century. Some experts believe that gas consumption may exceed that of the oil by the year 2025. Tight reservoirs contain no natural fractures, and cannot be produced economically without hydraulic fracturing fractured, tight and unconventional reservoirs are often perceived as entailing higher costs and risks than conventional reservoirs. However, new technologies developed in recent years are making more and more of these accumulations economical. The U.S. currently produces substantial volumes of natural from tight sands, gas shales, and coalbed-methane reservoirs. The tight gas reservoirs till date have been greatly ignored as gas sources in South Asia(196 Trillion cu.ft of discovered reserves compared to 1371

  14. Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Maria Cecilia Bravo

    2006-06-30

    This document reports progress of this research effort in identifying relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. These dependencies are investigated by identifying the main transport mechanisms at the pore scale that should affect fluids flow at the reservoir scale. A critical review of commercial reservoir simulators, used to predict tight sand gas reservoir, revealed that many are poor when used to model fluid flow through tight reservoirs. Conventional simulators ignore altogether or model incorrectly certain phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization. We studied the effect of Knudsen's number in Klinkenberg's equation and evaluated the effect of different flow regimes on Klinkenberg's parameter b. We developed a model capable of explaining the pressure dependence of this parameter that has been experimentally observed, but not explained in the conventional formalisms. We demonstrated the relevance of this, so far ignored effect, in tight sands reservoir modeling. A 2-D numerical simulator based on equations that capture the above mentioned phenomena was developed. Dynamic implications of new equations are comprehensively discussed in our work and their relative contribution to the flow rate is evaluated. We performed several simulation sensitivity studies that evidenced that, in general terms, our formalism should be implemented in order to get more reliable tight sands gas reservoirs' predictions.

  15. Leak testing of bubble-tight dampers using tracer gas techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lagus, P.L. [Lagus Applied Technology, Inc., San Diego, CA (United States); DuBois, L.J. [Commonwealth Edison, Zion, IL (United States); Fleming, K.M. [NCS Corporation, Columbus, OH (United States)] [and others

    1995-02-01

    Recently tracer gas techniques have been applied to the problem of measuring the leakage across an installed bubble-tight damper. A significant advantage of using a tracer gas technique is that quantitative leakage data are obtained under actual operating differential pressure conditions. Another advantage is that leakage data can be obtained using relatively simple test setups that utilize inexpensive materials without the need to tear ducts apart, fabricate expensive blank-off plates, and install test connections. Also, a tracer gas technique can be used to provide an accurate field evaluation of the performance of installed bubble-tight dampers on a periodic basis. Actual leakage flowrates were obtained at Zion Generating Station on four installed bubble-tight dampers using a tracer gas technique. Measured leakage rates ranged from 0.01 CFM to 21 CFM. After adjustment and subsequent retesting, the 21 CFM damper leakage was reduced to a leakage of 3.8 CFM. In light of the current regulatory climate and the interest in Control Room Habitability issues, imprecise estimates of critical air boundary leakage rates--such as through bubble-tight dampers--are not acceptable. These imprecise estimates can skew radioactive dose assessments as well as chemical contaminant exposure calculations. Using a tracer gas technique, the actual leakage rate can be determined. This knowledge eliminates a significant source of uncertainty in both radioactive dose and/or chemical exposure assessments.

  16. Potential restrictions for CO2 sequestration sites due to shale and tight gas production.

    Science.gov (United States)

    Elliot, T R; Celia, M A

    2012-04-01

    Carbon capture and geological sequestration is the only available technology that both allows continued use of fossil fuels in the power sector and reduces significantly the associated CO(2) emissions. Geological sequestration requires a deep permeable geological formation into which captured CO(2)can be injected, and an overlying impermeable formation, called a caprock, that keeps the buoyant CO(2) within the injection formation. Shale formations typically have very low permeability and are considered to be good caprock formations. Production of natural gas from shale and other tight formations involves fracturing the shale with the explicit objective to greatly increase the permeability of the shale. As such, shale gas production is in direct conflict with the use of shale formations as a caprock barrier to CO(2) migration. We have examined the locations in the United States where deep saline aquifers, suitable for CO(2) sequestration, exist, as well as the locations of gas production from shale and other tight formations. While estimated sequestration capacity for CO(2) sequestration in deep saline aquifers is large, up to 80% of that capacity has areal overlap with potential shale-gas production regions and, therefore, could be adversely affected by shale and tight gas production. Analysis of stationary sources of CO(2) shows a similar effect: about two-thirds of the total emissions from these sources are located within 20 miles of a deep saline aquifer, but shale and tight gas production could affect up to 85% of these sources. These analyses indicate that colocation of deep saline aquifers with shale and tight gas production could significantly affect the sequestration capacity for CCS operations. This suggests that a more comprehensive management strategy for subsurface resource utilization should be developed. PMID:22352312

  17. A wandering probe for tightness testing of the gas pipelines by means of the radiotracer method

    International Nuclear Information System (INIS)

    The report deals with the problem of the application of radiotracer techniques in the examination of the gas pipelines tightness. In particular, it gives a concise description of the construction of a special ''wandering probe'' for the localization of radiotracer leaks extorted in course of the measurements. (author)

  18. Naturally fractured tight gas reservoir detection optimization. Quarterly report, January 1, 1997--March 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    This document contains the quarterly report dated January 1-March 31, 1997 for the Naturally Fractured Tight Gas Reservoir Detection Optimization project. Topics covered in this report include AVOA modeling using paraxial ray tracing, AVOA modeling for gas- and water-filled fractures, 3-D and 3-C processing, and technology transfer material. Several presentations from a Geophysical Applications Workshop workbook, workshop schedule, and list of workshop attendees are also included.

  19. OPTIMIZATION OF INFILL DRILLING IN NATURALLY-FRACTURED TIGHT-GAS RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence W. Teufel; Her-Yuan Chen; Thomas W. Engler; Bruce Hart

    2004-05-01

    A major goal of industry and the U.S. Department of Energy (DOE) fossil energy program is to increase gas reserves in tight-gas reservoirs. Infill drilling and hydraulic fracture stimulation in these reservoirs are important reservoir management strategies to increase production and reserves. Phase II of this DOE/cooperative industry project focused on optimization of infill drilling and evaluation of hydraulic fracturing in naturally-fractured tight-gas reservoirs. The cooperative project involved multidisciplinary reservoir characterization and simulation studies to determine infill well potential in the Mesaverde and Dakota sandstone formations at selected areas in the San Juan Basin of northwestern New Mexico. This work used the methodology and approach developed in Phase I. Integrated reservoir description and hydraulic fracture treatment analyses were also conducted in the Pecos Slope Abo tight-gas reservoir in southeastern New Mexico and the Lewis Shale in the San Juan Basin. This study has demonstrated a methodology to (1) describe reservoir heterogeneities and natural fracture systems, (2) determine reservoir permeability and permeability anisotropy, (3) define the elliptical drainage area and recoverable gas for existing wells, (4) determine the optimal location and number of new in-fill wells to maximize economic recovery, (5) forecast the increase in total cumulative gas production from infill drilling, and (6) evaluate hydraulic fracture simulation treatments and their impact on well drainage area and infill well potential. Industry partners during the course of this five-year project included BP, Burlington Resources, ConocoPhillips, and Williams.

  20. Naturally fractured tight gas: Gas reservoir detection optimization. Quarterly report, January 1--March 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    Economically viable natural gas production from the low permeability Mesaverde Formation in the Piceance Basin, Colorado requires the presence of an intense set of open natural fractures. Establishing the regional presence and specific location of such natural fractures is the highest priority exploration goal in the Piceance and other western US tight, gas-centered basins. Recently, Advanced Resources International, Inc. (ARI) completed a field program at Rulison Field, Piceance Basin, to test and demonstrate the use of advanced seismic methods to locate and characterize natural fractures. This project began with a comprehensive review of the tectonic history, state of stress and fracture genesis of the basin. A high resolution aeromagnetic survey, interpreted satellite and SLAR imagery, and 400 line miles of 2-D seismic provided the foundation for the structural interpretation. The central feature of the program was the 4.5 square mile multi-azimuth 3-D seismic P-wave survey to locate natural fracture anomalies. The interpreted seismic attributes are being tested against a control data set of 27 wells. Additional wells are currently being drilled at Rulison, on close 40 acre spacings, to establish the productivity from the seismically observed fracture anomalies. A similar regional prospecting and seismic program is being considered for another part of the basin. The preliminary results indicate that detailed mapping of fault geometries and use of azimuthally defined seismic attributes exhibit close correlation with high productivity gas wells. The performance of the ten new wells, being drilled in the seismic grid in late 1996 and early 1997, will help demonstrate the reliability of this natural fracture detection and mapping technology.

  1. A new method of evaluating tight gas sands pore structure from nuclear magnetic resonance (NMR) logs

    Science.gov (United States)

    Xiao, Liang; Mao, Zhi-qiang; Xie, Xiu-hong

    2016-04-01

    Tight gas sands always display such characteristics of ultra-low porosity, permeability, high irreducible water, low resistivity contrast, complicated pore structure and strong heterogeneity, these make that the conventional methods are invalid. Many effective gas bearing formations are considered as dry zones or water saturated layers, and cannot be identified and exploited. To improve tight gas sands evaluation, the best method is quantitative characterizing rock pore structure. The mercury injection capillary pressure (MICP) curves are advantageous in predicting formation pore structure. However, the MICP experimental measurements are limited due to the environment and economy factors, this leads formation pore structure cannot be consecutively evaluated. Nuclear magnetic resonance (NMR) logs are considered to be promising in evaluating rock pore structure. Generally, to consecutively quantitatively evaluate tight gas sands pore structure, the best method is constructing pseudo Pc curves from NMR logs. In this paper, based on the analysis of lab experimental results for 20 core samples, which were drilled from tight gas sandstone reservoirs of Sichuan basin, and simultaneously applied for lab MICP and NMR measurements, the relationships of piecewise power function between nuclear magnetic resonance (NMR) transverse relaxation T2 time and pore-throat radius Rc are established. A novel method, which is used to transform NMR reverse cumulative curve as pseudo capillary pressure (Pc) curve is proposed, and the corresponding model is established based on formation classification. By using this model, formation pseudo Pc curves can be consecutively synthesized. The pore throat radius distribution, and pore structure evaluation parameters, such as the average pore throat radius (Rm), the threshold pressure (Pd), the maximum pore throat radius (Rmax) and so on, can also be precisely extracted. After this method is extended into field applications, several tight gas

  2. The 'tight gas' challenge: appraisal results from the Devonian of Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Hirst, J.P.P.; Davis, N.; Palmer, A.F.; Riddiford, F.A. [BP Amoco Exploration, Sunbury-on-Thames (United Kingdom); Achache, D. [Sonatrach, Boumerdes (Algeria)

    2001-02-01

    Projected future increases in Algerian gas production will, in part, come from more complex reservoirs within the Ahnet-Timimoun Basin; here, conventional quality reservoirs (>1 mD) are interbedded with volumetrically significant, low permeability sandstones (<1 mD) - the 'tight gas' sandstones. The challenge has been to develop a programme of work which will establish reserves in this sub-millidarcy resource; on balance, the results of this evaluation programme are positive. The main tight gas sections are of Lower Devonian age. Grain rimming chlorite cement within thin intervals locally inhibited later pervasive quartz cementation; the quartz is the cause of reservoir degradation in the bulk of the sandstone resulting in permeabilities of <1 mD, and often in the microdarcy range. Generally, the Lower Devonian has a low density of faulting and fractures; open and closed fractures are observed in core, whilst mud losses suggest some fractures are conductive in the subsurface. One of the main structures, the Teguentour Field, has been evaluated through the drilling of two new wells. The first of these wells (Teg-14) evaluated interbedded tight and conventional sandstones, whilst the second (Teg-15) was a dedicated tight sandstone completion involving an induced fracture programme. The permeability range in the tight gas sandstones extends below the resolution of conventional porosity/permeability measurement; determination has been improved through mercury injection derived permeabilities. Water saturations determined from core and log suggest gas may be present in the low permeability rock. The presence of gas could not be confirmed by formation tester samples and thus dynamic data were required from the Teg-15 well which was completed within the tight sandstone interval; only the top 5 m was perforated to limit the possibility of a communication pathway down to conventional quality sandstones. After nitrogen lift, the well flowed gas to surface at c. 5 x

  3. Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Maria Cecilia Bravo; Mariano Gurfinkel

    2005-06-30

    This document reports progress of this research effort in identifying possible relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. Based on a critical review of the available literature, a better understanding of the main weaknesses of the current state of the art of modeling and simulation for tight sand reservoirs has been reached. Progress has been made in the development and implementation of a simple reservoir simulator that is still able to overcome some of the deficiencies detected. The simulator will be used to quantify the impact of microscopic phenomena in the macroscopic behavior of tight sand gas reservoirs. Phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization are being considered as part of this study. To date, the adequate modeling of gas slippage in porous media has been determined to be of great relevance in order to explain unexpected fluid flow behavior in tight sand reservoirs.

  4. Imaging pore space in tight gas sandstone reservoir: insights from broad ion beam cross-sectioning

    Directory of Open Access Journals (Sweden)

    Konstanty J.

    2010-06-01

    Full Text Available Monetization of tight gas reservoirs, which contain significant gas reserves world-wide, represents a challenge for the entire oil and gas industry. The development of new technologies to enhance tight gas reservoir productivity is strongly dependent on an improved understanding of the rock properties and especially the pore framework. Numerous methods are now available to characterize sandstone cores. However, the pore space characterization at pore scale remains difficult due to the fine pore size and delicate sample preparation, and has thus been mostly indirectly inferred until now. Here we propose a new method of ultra high-resolution petrography combining high resolution SEM and argon ion beam cross sectioning (BIB, Broad Ion Beam which prepares smooth and damage free surfaces. We demonstrate this method using the example of Permian (Rotliegend age tight gas sandstone core samples. The combination of Ar-beam cross-sectioning facility and high-resolution SEM imaging has the potential to result in a step change in the understanding of pore geometries, in terms of its morphology, spatial distribution and evolution based on the generation of unprecedented image quality and resolution enhancing the predictive reliability of image analysis.

  5. Pore structure and limit pressure of gas slippage effect in tight sandstone.

    Science.gov (United States)

    You, Lijun; Xue, Kunlin; Kang, Yili; Liao, Yi; Kong, Lie

    2013-01-01

    Gas slip effect is an important mechanism that the gas flow is different from liquid flow in porous media. It is generally considered that the lower the permeability in porous media is, the more severe slip effect of gas flow will be. We design and then carry out experiments with the increase of backpressure at the outlet of the core samples based on the definition of gas slip effect and in view of different levels of permeability of tight sandstone reservoir. This study inspects a limit pressure of the gas slip effect in tight sandstones and analyzes the characteristic parameter of capillary pressure curves. The experimental results indicate that gas slip effect can be eliminated when the backpressure reaches a limit pressure. When the backpressure exceeds the limit pressure, the measured gas permeability is a relatively stable value whose range is less than 3% for a given core sample. It is also found that the limit pressure increases with the decreasing in permeability and has close relation with pore structure of the core samples. The results have an important influence on correlation study on gas flow in porous medium, and are beneficial to reduce the workload of laboratory experiment.

  6. Estimation of Permeability from NMR Logs Based on Formation Classification Method in Tight Gas Sands

    Science.gov (United States)

    Wei, Deng-Feng; Liu, Xiao-Peng; Hu, Xiao-Xin; Xu, Rui; Zhu, Ling-Ling

    2015-10-01

    The Schlumberger Doll Research (SDR) model and cross plot of porosity versus permeability cannot be directly used in tight gas sands. In this study, the HFU approach is introduced to classify rocks, and determine the involved parameters in the SDR model. Based on the difference of FZI, 87 core samples, drilled from tight gas sandstones reservoirs of E basin in northwest China and applied for laboratory NMR measurements, were classified into three types, and the involved parameters in the SDR model are calibrated separately. Meanwhile, relationships of porosity versus permeability are also established. The statistical model is used to calculate consecutive FZI from conventional logs. Field examples illustrate that the calibrated SDR models are applicable in permeability estimation; models established from routine core analyzed results are effective in reservoirs with permeability lower than 0.3 mD, while the unified SDR model is only valid in reservoirs with permeability ranges from 0.1 to 0.3 mD.

  7. The tightness of the globe valves in the exploitations practice of the gas pipe-lines

    International Nuclear Information System (INIS)

    Technological units of the Transit Gas Pipeline (i.e. Compressor Stations, Valve Stations, Stations or National Network Service Installations) have been fitted with Ball Valves as shut-off devices (block valves). Internal tightness of the valves' seat becomes major factor in securing proper service conditions during normal pipeline operation as well as for isolating of pipeline sections in emergency situations (loss of pipeline integrity or uncontrolled gas escape). Internal tightness of the valves is being inspected during scheduled maintenance of the pipeline units. Any leak revealed during inspection is being repaired, following instructions provided in the Manufacturer's Valve Manual. After a time, some cases have been identified, when repair of the revealed leak was found to be difficult, despite close following of the repair manuals. The paper presents analysis of the issue and corrective actions taken accordingly. (authors)

  8. Shale Gas and Tight Oil: A Panacea for the Energy Woes of America?

    Science.gov (United States)

    Hughes, J. D.

    2012-12-01

    Shale gas has been heralded as a "game changer" in the struggle to meet America's demand for energy. The "Pickens Plan" of Texas oil and gas pioneer T.Boone Pickens suggests that gas can replace coal for much of U.S. electricity generation, and oil for, at least, truck transportation1. Industry lobby groups such as ANGA declare "that the dream of clean, abundant, home grown energy is now reality"2. In Canada, politicians in British Columbia are racing to export the virtual bounty of shale gas via LNG to Asia (despite the fact that Canadian gas production is down 16 percent from its 2001 peak). And the EIA has forecast that the U.S. will become a net exporter of gas by 20213. Similarly, recent reports from Citigroup and Harvard suggest that an oil glut is on the horizon thanks in part to the application of fracking technology to formerly inaccessible low permeability tight oil plays. The fundamentals of well costs and declines belie this optimism. Shale gas is expensive gas. In the early days it was declared that "continuous plays" like shale gas were "manufacturing operations", and that geology didn't matter. One could drill a well anywhere, it was suggested, and expect consistent production. Unfortunately, Mother Nature always has the last word, and inevitably the vast expanses of purported potential shale gas resources contracted to "core" areas, where geological conditions were optimal. The cost to produce shale gas ranges from 4.00 per thousand cubic feet (mcf) to 10.00, depending on the play. Natural gas production is a story about declines which now amount to 32% per year in the U.S. So 22 billion cubic feet per day of production now has to be replaced each year to keep overall production flat. At current prices of 2.50/mcf, industry is short about 50 billion per year in cash flow to make this happen4. As a result I expect falling production and rising prices in the near to medium term. Similarly, tight oil plays in North Dakota and Texas have been heralded

  9. Study of Gas Flow Characteristics in Tight Porous Media with a Microscale Lattice Boltzmann Model.

    Science.gov (United States)

    Zhao, Jianlin; Yao, Jun; Zhang, Min; Zhang, Lei; Yang, Yongfei; Sun, Hai; An, Senyou; Li, Aifen

    2016-01-01

    To investigate the gas flow characteristics in tight porous media, a microscale lattice Boltzmann (LB) model with the regularization procedure is firstly adopted to simulate gas flow in three-dimensional (3D) digital rocks. A shale digital rock and a sandstone digital rock are reconstructed to study the effects of pressure, temperature and pore size on microscale gas flow. The simulation results show that because of the microscale effect in tight porous media, the apparent permeability is always higher than the intrinsic permeability, and with the decrease of pressure or pore size, or with the increase of temperature, the difference between apparent permeability and intrinsic permeability increases. In addition, the Knudsen numbers under different conditions are calculated and the results show that gas flow characteristics in the digital rocks under different Knudsen numbers are quite different. With the increase of Knudsen number, gas flow in the digital rocks becomes more uniform and the effect of heterogeneity of the porous media on gas flow decreases. Finally, two commonly used apparent permeability calculation models are evaluated by the simulation results and the Klinkenberg model shows better accuracy. In addition, a better proportionality factor in Klinkenberg model is proposed according to the simulation results. PMID:27587293

  10. Enhanced recovery of unconventional gas. Volume II. The program. [Tight gas basins; Devonian shale; coal seams; geopressured aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Kuuskraa, V.A.; Brashear, J.P.; Doscher, T.M.; Elkins, L.E.

    1978-10-01

    This study was conducted to assist public decision-makers in selecting among many choices to obtain new gas supplies by addressing 2 questions: 1) how severe is the need for additional future supplies of natural gas, and what is the economic potential of providing part of future supply through enhanced recovery from unconventional natural gas resources. The study also serves to assist the DOE in designing a cost-effective R and D program to stimulate industry to recover this unconventional gas and to produce it sooner. Tight gas basins, Devonian shale, methane from coal seams, and methane from geopressured aquifers are considered. It is concluded that unconventional sources, already providing about 1 Tcf per year, could provide from 3 to 4 Tcf in 1985 and from 6 to 8 Tcf in 1990 (at $1.75 and $3.00 per Mcf, respectively). However, even with these additions to supply, gas supply is projected to remain below 1977 usage levels. (DLC)

  11. Pore-scale mechanisms of gas flow in tight sand reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Silin, D.; Kneafsey, T.J.; Ajo-Franklin, J.B.; Nico, P.

    2010-11-30

    Tight gas sands are unconventional hydrocarbon energy resource storing large volume of natural gas. Microscopy and 3D imaging of reservoir samples at different scales and resolutions provide insights into the coaredo not significantly smaller in size than conventional sandstones, the extremely dense grain packing makes the pore space tortuous, and the porosity is small. In some cases the inter-granular void space is presented by micron-scale slits, whose geometry requires imaging at submicron resolutions. Maximal Inscribed Spheres computations simulate different scenarios of capillary-equilibrium two-phase fluid displacement. For tight sands, the simulations predict an unusually low wetting fluid saturation threshold, at which the non-wetting phase becomes disconnected. Flow simulations in combination with Maximal Inscribed Spheres computations evaluate relative permeability curves. The computations show that at the threshold saturation, when the nonwetting fluid becomes disconnected, the flow of both fluids is practically blocked. The nonwetting phase is immobile due to the disconnectedness, while the permeability to the wetting phase remains essentially equal to zero due to the pore space geometry. This observation explains the Permeability Jail, which was defined earlier by others. The gas is trapped by capillarity, and the brine is immobile due to the dynamic effects. At the same time, in drainage, simulations predict that the mobility of at least one of the fluids is greater than zero at all saturations. A pore-scale model of gas condensate dropout predicts the rate to be proportional to the scalar product of the fluid velocity and pressure gradient. The narrowest constriction in the flow path is subject to the highest rate of condensation. The pore-scale model naturally upscales to the Panfilov's Darcy-scale model, which implies that the condensate dropout rate is proportional to the pressure gradient squared. Pressure gradient is the greatest near the

  12. Black hole mergers: do gas discs lead to spin alignment?

    OpenAIRE

    Lodato, Giuseppe; Gerosa, Davide

    2012-01-01

    In this Letter we revisit arguments suggesting that the Bardeen-Petterson effect can coalign the spins of a central supermassive black hole binary accreting from a circumbinary (or circumnuclear) gas disc. We improve on previous estimates by adding the dependence on system parameters, and noting that the nonlinear nature of warp propagation in a thin viscous disc affects alignment. This reduces the disc's ability to communicate the warp, and can severely reduce the effectiveness of disc-assis...

  13. Anoxic incubation of sediment in gas-tight plastic bags: a method for biogeochemical process studies

    DEFF Research Database (Denmark)

    Hansen, JW; Thamdrup, B.; Jørgensen, BB

    2000-01-01

    Incubation of sediment in gas-tight plastic bags is described as a method for experimental studies of biogeochemical processes. Sediment incubation in these bags allows time-course experiments to be conducted on homogenised sediment without dilution, continuous stirring, or gaseous head-space. Co......Incubation of sediment in gas-tight plastic bags is described as a method for experimental studies of biogeochemical processes. Sediment incubation in these bags allows time-course experiments to be conducted on homogenised sediment without dilution, continuous stirring, or gaseous head......-space. Consequently, bag incubations of sediment combine the advantage of low heterogeneity in slurry incubations with the more natural conditions in jar and whole-core incubations. The bag material is a transparent laminated plastic comprised of Nylon, ethylenevinyl alcohol, and polyethylene with a low permeability...... for the studied gases: O-2, CO2, H2S, CH4, N-2, H-2, and He. Estimated fluxes of biologically active gases through the plastic bag during sediment incubation were insignificant compared to rates of microbial processes and to gas concentrations in coastal sediments. An exception was CH4, for which process...

  14. Shale and tight gas in Poland—legal and environmental issues

    International Nuclear Information System (INIS)

    Exploitation of unconventional gas is limited by a number of economic, legal, environmental and social factors. When it comes to Poland, legal and environmental factors are of special importance, as they might significantly impact the exploitation of both tight gas and shale gas. Exploitation of unconventional gas deposits, because of the technology needed for opening of these deposits, has relatively great impact on the balance sheet and the quality of water. Polish water resources are limited and depend on time and local circumstances. Therefore, obtaining adequate amounts of water needed to hydraulic fracturing of unconventional gas reservoirs may cause some problems. Another problem is return water management. Injection of contaminated water into the rockmass on a large scale seems to be impossible in Poland. Water discharge to surface waters, which seems to be the most probable solution, would result in deterioration of the purity of Polish rivers. Around 32% of Poland is covered by different forms of protection, which might include limitations in exploitation of hydrocarbon deposits (depending on the type of area). Exploration, documentation and exploitation of unconventional gas in Poland is regulated mainly by the laws and regulations regulating geological and mining activities, environmental protection and waste management. - Highlights: • Legal and environmental issues were analyzed regarding unconventional gas exploitation in Poland. • Limited water resources and large areas of environmental protection might be critical for the unconventional gas production. • Exploitation of unconventional gas was primarily regulated by the Geological and mining law and environmental act. • Regulations presented in this paper, are aimed to encouraging investors to search for shale gas

  15. ADVANCED FRACTURING TECHNOLOGY FOR TIGHT GAS: AN EAST TEXAS FIELD DEMONSTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Mukul M. Sharma

    2005-03-01

    The primary objective of this research was to improve completion and fracturing practices in gas reservoirs in marginal plays in the continental United States. The Bossier Play in East Texas, a very active tight gas play, was chosen as the site to develop and test the new strategies for completion and fracturing. Figure 1 provides a general location map for the Dowdy Ranch Field, where the wells involved in this study are located. The Bossier and other tight gas formations in the continental Unites States are marginal plays in that they become uneconomical at gas prices below $2.00 MCF. It was, therefore, imperative that completion and fracturing practices be optimized so that these gas wells remain economically attractive. The economic viability of this play is strongly dependent on the cost and effectiveness of the hydraulic fracturing used in its well completions. Water-fracs consisting of proppant pumped with un-gelled fluid is the type of stimulation used in many low permeability reservoirs in East Texas and throughout the United States. The use of low viscosity Newtonian fluids allows the creation of long narrow fractures in the reservoir, without the excessive height growth that is often seen with cross-linked fluids. These low viscosity fluids have poor proppant transport properties. Pressure transient tests run on several wells that have been water-fractured indicate a long effective fracture length with very low fracture conductivity even when large amounts of proppant are placed in the formation. A modification to the water-frac stimulation design was needed to transport proppant farther out into the fracture. This requires suspending the proppant until the fracture closes without generating excessive fracture height. A review of fracture diagnostic data collected from various wells in different areas (for conventional gel and water-fracs) suggests that effective propped lengths for the fracture treatments are sometimes significantly shorter than those

  16. Black hole mergers: do gas discs lead to spin alignment?

    CERN Document Server

    Lodato, Giuseppe

    2012-01-01

    In this Letter we revisit arguments suggesting that the Bardeen-Petterson effect can coalign the spins of a central supermassive black hole binary accreting from a circumbinary (or circumnuclear) gas disc. We improve on previous estimates by adding the dependence on system parameters, and noting that the nonlinear nature of warp propagation in a thin viscous disc affects alignment. This reduces the disc's ability to communicate the warp, and can severely reduce the effectiveness of disc-assisted spin alignment. We test our predictions with a Monte Carlo realization of random misalignments and accretion rates and we find that the outcome depends strongly on the spin magnitude. We estimate a generous upper limit to the probability of alignment by making assumptions which favour it throughout. Even with these assumptions, about 40% of black holes with $a \\gtrsim 0.5$ do not have time to align with the disc. If the residual misalignment is not small and it is maintained down to the final coalescence phase this ca...

  17. Black hole mergers: do gas discs lead to spin alignment?

    Science.gov (United States)

    Lodato, Giuseppe; Gerosa, Davide

    2013-02-01

    In this Letter, we revisit arguments suggesting that the Bardeen-Petterson effect can coalign the spins of a central supermassive black hole binary accreting from a circumbinary (or circumnuclear) gas disc. We improve on previous estimates by adding the dependence on system parameters and noting that the non-linear nature of warp propagation in a thin viscous disc affects alignment. This reduces the disc's ability to communicate the warp, and can severely reduce the effectiveness of disc-assisted spin alignment. We test our predictions with a Monte Carlo realization of random misalignments and accretion rates, and we find that the outcome depends strongly on the spin magnitude. We estimate a generous upper limit to the probability of alignment by making assumptions which favour it throughout. Even with these assumptions, about 40 per cent of black holes with a ≳ 0.5 do not have time to align with the disc. If the residual misalignment is not small and it is maintained down to the final coalescence phase, this can give a powerful recoil velocity to the merged hole. Highly spinning black holes are thus more likely being subject to strong recoils, the occurrence of which is currently debated.

  18. Estimation of Permeability from NMR Logs Based on Formation Classification Method in Tight Gas Sands

    Directory of Open Access Journals (Sweden)

    Wei Deng-Feng

    2015-10-01

    Full Text Available The Schlumberger Doll Research (SDR model and cross plot of porosity versus permeability cannot be directly used in tight gas sands. In this study, the HFU approach is introduced to classify rocks, and determine the involved parameters in the SDR model. Based on the difference of FZI, 87 core samples, drilled from tight gas sandstones reservoirs of E basin in northwest China and applied for laboratory NMR measurements, were classified into three types, and the involved parameters in the SDR model are calibrated separately. Meanwhile, relationships of porosity versus permeability are also established. The statistical model is used to calculate consecutive FZI from conventional logs. Field examples illustrate that the calibrated SDR models are applicable in permeability estimation; models established from routine core analyzed results are effective in reservoirs with permeability lower than 0.3 mD, while the unified SDR model is only valid in reservoirs with permeability ranges from 0.1 to 0.3 mD.

  19. Postbuildup drawdown analysis of tight gas wells in the Rocky Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Hale, B.W.; Firth, C.H.; Hansen, R.C.; Murphy, M.J.; Woodcox, S.C. (Northwest Pipeline Corp. (US))

    1989-08-01

    Through the use of recently available daily volume data on Northwest Pipeline Corp.'s gathering systems, drawdown following pressure buildups can be analyzed to predict flush production behavior of tight gas wells that have been shut in, perhaps owing to market restrictions. The flush rate as a percentage of the final flowing rate is a function of flowing time after the buildup. The magnitude of the initial flush rate is related to the length of time the well is shut in, to the final flow rate before shut-in, and to the age of the well. The amount of flush production increases as the well downtime increases. Daily production histories of the wells on the Douglas Creek Arch and the Green River, San Juan, Piceance, and Uinta basins were studied. Wells within each area were grouped by geologic formation, by flow rate, and by similar periods of shut-in time. When plotted on a log-log scale, the ratio of the postbuildup rate to the stable rate shows a straight-line relationship to the drawdown time. Theoretical curves to predict flow rates after a buildup are presented that are based on the superposition of constant-pressure solutions to the flow of a real gas in a porous medium and that show a nearly straight-line rate/time relationship. In light of the current gas surplus and the evolving spot market, the prediction of accurate short-term performance is useful in scheduling gas sales and gas transportation.

  20. Investigation of hydraulic fracture re-orientation effects in tight gas reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Hagemann, B.; Wegner, J.; Ganzer, L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE

    2013-08-01

    In tight gas formations where the low matrix permeability prevents successful and economic production rates, hydraulic fracturing is required to produce a well at economic rates. The initial fracture opens in the direction of minimum stress and propagates into the direction of maximum stress. As production from the well and its initial fracture declines, re-fracturing treatments are required to accelerate recovery. The orientation of the following hydraulic fracture depends on the actual stress-state of the formation in the vicinity of the wellbore. Previous investigations by Elbel and Mack (1993) demonstrated that the stress alters during depletion and a stress reversal region appears. This behavior causes a different fracture orientation of the re-fracturing operation. For the investigation of re-fracture orientation a two-dimensional reservoir model has been designed using COMSOL Multiphysics. The model represents a fractured vertical well in a tight gas reservoir of infinite thickness. A time dependent study was set up to simulate the reservoir depletion by the production from the fractured well. The theory of poroelasticity was used to couple the fluid flow and geo-mechanical behavior. The stress state is initially defined as uniform and the attention is concentrated to the alteration of stress due to the lowered pore pressure. Different cases with anisotropic and heterogeneous permeability are set up to determine its significance. The simulation shows that an elliptical shaped drainage area appears around the fracture. The poroelastic behavior effects that the stress re-orientates and a stress reversal region originates, if the difference between minimum and maximum horizontal stresses is small. The consideration of time indicates that the dimension of the region initially extends fast until it reaches its maximum. Subsequently, the stress reversal region's extent shrinks slowly until it finally disappears. The reservoir characteristics, e.g. the

  1. Design philosophy and practice of asymmetrical 3D fracturing and random fracturing: A case study of tight sand gas reservoirs in western Sichuan Basin

    OpenAIRE

    Jianchun Guo; Bo Gou

    2015-01-01

    At present two technical models are commonly taken in tight gas reservoir stimulation: conventional massive fracturing and SRV fracturing, but how to select a suitable fracturing model suitable for reservoir characteristics is still a question waiting to be answered. In this paper, based on the analysis of geological characteristics and seepage mechanism of tight gas and shale gas reservoirs, the differences between stimulation philosophy of tight gas reservoirs and shale reservoirs are eluci...

  2. Design and Implementation of Energized Fracture Treatment in Tight Gas Sands

    Energy Technology Data Exchange (ETDEWEB)

    Mukul Sharma; Kyle Friehauf

    2009-12-31

    , the minimum CO{sub 2} gas quality (volume % of gas) recommended is 30% for moderate differences between fracture and reservoir pressures (2900 psi reservoir, 5300 psi fracture). The minimum quality is reduced to 20% when the difference between pressures is larger, resulting in additional gas expansion in the invaded zone. Inlet fluid temperature, flow rate, and base viscosity did not have a large impact on fracture production. Finally, every stage of the fracturing treatment should be energized with a gas component to ensure high gas saturation in the invaded zone. A second, more general, sensitivity study was conducted. Simulations show that CO{sub 2} outperforms N{sub 2} as a fluid component because it has higher solubility in water at fracturing temperatures and pressures. In fact, all gas components with higher solubility in water will increase the fluid's ability to reduce damage in the invaded zone. Adding methanol to the fracturing solution can increase the solubility of CO{sub 2}. N{sub 2} should only be used if the gas leaks-off either during the creation of the fracture or during closure, resulting in gas going into the invaded zone. Experimental data is needed to determine if the gas phase leaks-off during the creation of the fracture. Simulations show that the bubbles in a fluid traveling across the face of a porous medium are not likely to attach to the surface of the rock, the filter cake, or penetrate far into the porous medium. In summary, this research has created the first compositional fracturing simulator, a useful tool to aid in energized fracture design. We have made several important and original conclusions about the best practices when using energized fluids in tight gas sands. The models and tools presented here may be used in the future to predict behavior of any multi-phase or multi-component fracturing fluid system.

  3. Unconventional gas experience at El Paso Production Company : tapping into deep, tight gas and coalbed methane

    International Nuclear Information System (INIS)

    The current conditions in the natural gas industry were reviewed, from the excellent current and projected energy prices to low activity and rig count. Various graphs were presented, depicting total proved dry gas reserves and annual production over time for the Gulf of Mexico, including its continental shelf, the Texas coastal plains, and the United States lower 48. Offshore growth of unconventional gas was also displayed. The key elements of the strategy were also discussed. These included: (1) earnings driven, (2) superior science, (3) innovative application of technology, (4) ability to act quickly and decisively, (5) leadership, management, and professional development, and (6) achieve learning curve economics. The core competencies were outlined along with recent discoveries in South Texas and the Upper Gulf Coast. figs

  4. Remote sensing of fugitive methane emissions from oil and gas production in North American tight geologic formations

    OpenAIRE

    Schneising, Oliver; Burrows, John P.; Dickerson, Russell R.; Buchwitz, Michael; Reuter, Maximilian; BOVENSMANN Heinrich

    2014-01-01

    In the past decade, there has been a massive growth in the horizontal drilling and hydraulic fracturing of shale gas and tight oil reservoirs to exploit formerly inaccessible or unprofitable energy resources in rock formations with low permeability. In North America, these unconventional domestic sources of natural gas and oil provide an opportunity to achieve energy self-sufficiency and to reduce greenhouse gas emissions when displacing coal as a source of energy in power plants. However, fu...

  5. Diagenetic facies controls on pore structure and rock electrical parameters in tight gas sandstone

    Science.gov (United States)

    Liu, Hongping; Zhao, Yanchao; Luo, Yang; Chen, Zhaoyou; He, Sheng

    2015-08-01

    Rock electrical parameters of tight gas sandstone show large variations in the T2 member in Dingbei Block, Ordos Basin, China. Applying the same rock electrical parameters in water saturation calculations would lead to large errors. Based on casting thin sections, x-ray diffraction, scanning electron microscopy (SEM), cathode luminescence, porosity and permeability, image analysis, and high-pressure mercury intrusion/withdrawal method, identification of the diagenetic facies are first conducted, and then their pore structure and their relationship with rock electrical parameters are investigated. Five diagenetic facies (A-E), which are identified based mainly on pore types and authigenic minerals, have different pore structure and rock electrical parameters. Conceptual models that incorporate the rock properties of each diagenetic facies have been built, before applying the electrical efficiency theory to explain the values of cementation exponent (m) and saturation exponent (n). A conventional network model, a shunt pore model, a netted pore model, and a dotted line model are utilized to mimic the intergranular pores, authigenic kaolinite intercrystal pores, carbonate-cement dissolution pores, and clay-matrix intercrystal pores, respectively. A decrease of the contents of large pores increases electrical efficiency and therefore reduces m. The saturation exponent, which depends on the distribution of water and gas, can be better understood by applying the different pore models. In the shunt and netted pore models, gas displacement starts from the larger pores and smaller pores provide alternative conduction pathways, hence sustaining electrical efficiency and decreasing n. Clay-matrix intercrystal pores are mainly micropores, since the brine in the rocks are isolated after gas displacement, reducing overall electrical efficiency and dramatically increasing the value of n in the diagenetic facies, which is dominated by clay-matrix intercrystal pores.

  6. Optimized Design and Use of Induced Complex Fractures in Horizontal Wellbores of Tight Gas Reservoirs

    Science.gov (United States)

    Zeng, F. H.; Guo, J. C.

    2016-04-01

    Multistage hydraulic fracturing is being increasing use in the establishment of horizontal wells in tight gas reservoirs. Connecting hydraulic fractures to natural and stress-induced fractures can further improve well productivity. This paper investigates the fracture treatment design issues involved in the establishment of horizontal wellbores, including the effects of geologic heterogeneity, perforation parameters, fracturing patterns, and construction parameters on stress anisotropy during hydraulic fracturing and on natural fractures during hydraulic fracture propagation. The extent of stress reversal and reorientation was calculated for fractures induced by the creation of one or more propped fractures. The effects of stress on alternate and sequential fracturing horizontal well and on the reservoir's mechanical properties, including the spatial extent of stress reorientation caused by the opening of fractures, were assessed and quantified. Alternate sequencing of transverse fractures was found to be an effective means of enhancing natural fracture stimulation by allowing fractures to undergo less stress contrast during propagation. The goal of this paper was to present a new approach to design that optimizes fracturing in a horizontal wellbore from the perspectives of both rock mechanics and fluid production. The new design is a modified version of alternate fracturing, where the fracture-initiation sequence was controlled by perforation parameters with a staggered pattern within a horizontal wellbore. Results demonstrated that the modified alternate fracturing performed better than original sequence fracturing and that this was because it increased the contact area and promoted more gas production in completed wells.

  7. Structural diagenesis in Upper Carboniferous tight gas sandstones. Lessons learned from the Piesberg analog study

    Energy Technology Data Exchange (ETDEWEB)

    Steindorf, P.; Hoehne, M.; Becker, S.; Hilgers, C. [RWTH Aachen Univ. (Germany). Energy and Mineral Resources Group (EMR); Koehrer, B. [Wintershall Holding GmbH, Barnstorf (Germany)

    2013-08-01

    Upper Carboniferous tight gas sandstone reservoirs in NW-Germany consist of thick successions of cyclothems. Our focus is the Westphalian D of the Piesberg quarry near Osnabrueck, which exposes cemented, faulted and jointed third-order coarse- to fine-grained sandstone cycles separated by anthracite coal seams. We characterize the rocks and the lateral variation of rock properties such as porosity to better constrain input data for reservoir modelling. Three cycles are exposed, each approximately 50 m thick. Rock types can be clearly distinguished by spectral gamma ray in the quarry. Sandstones are intensely compacted and cemented with quartz and generally characterized by low porosities < 8 % (Hepycnometry on plugs and cuttings). Porosities are secondary and mainly related to detrital carbonate dissolution. Around faults dissolution is higher and the porosities can increase to up to 25%. The normal faults show different throws in the quarry and bands of shale and coal have smeared into the fault at juxtaposed beds, which may result in compartments. They dominantly strike W-E and NNW-SSE, but subordinate NE-SW striking fault patterns are also present. Joints were analyzed in a 50 x 50 m section of the quarry wall using Lidar (Light detection and ranging) laser scanning, which allows the characterization of the lithology and quantitative measurement of bedding and fracture orientation data in inaccessible areas. NNE-SSW and W-E joint sets are accompanied by northeasterly and northwesterly striking sets. Around faults, fault planes and fractures are cemented with quartz veins, showing localized mass transport. Due to the intense cementation, the sandstones can reach uniaxial strengths of more than 100 MPa normal to bedding, and approximately 50 MPa parallel to bedding. Sandstone beds within and close to faults are leached by fluids, and their uniaxial strength is reduced by a factor of more than two. Our high resolution field data enables a better understanding of

  8. The RealGas and RealGasH2O options of the TOUGH+ code for the simulation of coupled fluid and heat flow in tight/shale gas systems

    Science.gov (United States)

    We developed two new EOS additions to the TOUGH+ family of codes, the RealGasH2O and RealGas. The RealGasH2O EOS option describes the non-isothermal two-phase flow of water and a real gas mixture in gas reservoirs, with a particular focus in ultra-tight (such as tight-sand and sh...

  9. Tectonic Fractures in Tight Gas Sandstones of the Upper Triassic Xujiahe Formation in the Western Sichuan Basin,China

    Institute of Scientific and Technical Information of China (English)

    ZENG Lianbo; LI Yuegang

    2010-01-01

    The western Sichuan Basin,which is located at the front of the Longmen Mountains in the west of Sichuan Province,China,is a foreland basin formed in the Late Triassic.The Upper Triassic Xujiahe Formation is a tight gas sandstone reservoir with low porosity and ultra-low permeability,whose gas accumulation and production are controlled by well-developed fracture zones.There are mainly three types of fractures developed in the Upper Triassic tight gas sandstones,namely tectonic fractures,diagenetic fractures and overpressure-related fractures,of which high-angle tectonic fractures are the most important.The tectonic fractures can be classified into four sets,i.e.,N-S-,NE-,E-W-and NW-striking fractures.In addition,there are a number of approximately horizontal shear fractures in some of the medium-grained sandstones and grit stones nearby the thrusts or slip layers.Tectonic fractures were mainly formed at the end of the Triassic,the end of the Cretaceous and the end of the Neogene-Early Pleistocene.The development degree of tectonic fractures was controlled by lithology,thickness,structure,stress and fluid pressure.Overpressure makes not only the rock shear strength decrease,but also the stress state change from compression to tension.Thus,tensional fractures can be formed in fold-thrust belts.Tectonic fractures are mainly developed along the NE-and N-S-striking structural belts,and are the important storage space and the principal flow channels in the tight gas sandstone.The porosity of fractures here is 28.4% of the gross reservoir porosity,and the permeability of fractures being two or three grades higher than that of the matrix pores.Four sets of high-angle tectonic fractures and horizontal shear fractures formed a good network system and controlled the distribution and production of gas in the tight sandstones.

  10. A sampling system for collecting gas-tight time-series hydrothermal fluids

    Science.gov (United States)

    Wu, S.; Yang, C.; Ding, K.

    2012-12-01

    It is known that the hydrothermal venting has temporal variations associated with tectonic and geochemical processes. To date, the methods for long-term monitoring of the seafloor hydrothermal systems are rare. A new sampling system has been designed to be deployed at seafloor for long term to collect gas-tight time-series samples from hydrothermal vents. Based on the modular design principle, the sampling system is currently composed of a control module and six sampling modules, which is convenient to be upgraded by adding more sampling modules if needed. The control module consists of a rechargeable battery pack and a circuit board with functions of sampling control, temperature measurement, data storage and communication. Each sampling module has an independent sampling valve, a valve actuator and a sampling cylinder. The sampling cylinder consists of a sample chamber and an accumulator chamber. Compressed nitrogen gas is used to maintain the sample at in-situ pressure. A prototype of the sampling system has been constructed and tested. First, the instrument was tested in a high-pressure vessel at a pressure of 40 MPa. Six sampling modules were successfully triggered and water samples were collected and kept at in-situ pressure after experiment. Besides, the instrument was field tested at the shallow hydrothermal field near off Kueishantao islet (24°51'N, 121°55'E), which is located offshore of northeastern Taiwan, from May 25 to May 28, 2011. The sampling system worked at an automatic mode. Each sampling module was triggered according to the preset time. Time-series hydrothermal fluids have been collected from a shallow hydrothermal vent with a depth of 16 m. The preliminary tests indicated the success of the design and construction of the prototype of the sampling system. Currently, the sampling system is being upgraded by integration of a DC-DC power conversion and serial-to-Ethernet conversion module, so that it can utilize the continuous power supply and

  11. Preparation of gas-tight strontium-doped lanthanum cobaltate by an aqueous sol-gel process

    NARCIS (Netherlands)

    Chen, C.H.; Kruidhof, H.; Bouwmeester, H.J.M.; Burggraaf, A.J.

    1996-01-01

    Gas-tight dense membranes of highly Sr-doped LaCoO3 (such as the composition La0.3Sr0.7CoO3 chosen in this study) are difficult to prepare using usual synthesis processes. This report presents an aqueous sol-gel route using metal acetates as precursors to achieve this goal. Hydrogen peroxide and amm

  12. Analysis of Critical Permeabilty, Capillary Pressure and Electrical Properties for Mesaverde Tight Gas Sandstones from Western U.S. Basins

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; Robert Cluff; John Webb; John Victorine; Ken Stalder; Daniel Osburn; Andrew Knoderer; Owen Metheny; Troy Hommertzheim; Joshua Byrnes; Daniel Krygowski; Stefani Whittaker

    2008-06-30

    Although prediction of future natural gas supply is complicated by uncertainty in such variables as demand, liquefied natural gas supply price and availability, coalbed methane and gas shale development rate, and pipeline availability, all U.S. Energy Information Administration gas supply estimates to date have predicted that Unconventional gas sources will be the dominant source of U.S. natural gas supply for at least the next two decades (Fig. 1.1; the period of estimation). Among the Unconventional gas supply sources, Tight Gas Sandstones (TGS) will represent 50-70% of the Unconventional gas supply in this time period (Fig. 1.2). Rocky Mountain TGS are estimated to be approximately 70% of the total TGS resource base (USEIA, 2005) and the Mesaverde Group (Mesaverde) sandstones represent the principal gas productive sandstone unit in the largest Western U.S. TGS basins including the basins that are the focus of this study (Washakie, Uinta, Piceance, northern Greater Green River, Wind River, Powder River). Industry assessment of the regional gas resource, projection of future gas supply, and exploration programs require an understanding of reservoir properties and accurate tools for formation evaluation. The goal of this study is to provide petrophysical formation evaluation tools related to relative permeability, capillary pressure, electrical properties and algorithms for wireline log analysis. Detailed and accurate moveable gas-in-place resource assessment is most critical in marginal gas plays and there is need for quantitative tools for definition of limits on gas producibility due to technology and rock physics and for defining water saturation. The results of this study address fundamental questions concerning: (1) gas storage; (2) gas flow; (3) capillary pressure; (4) electrical properties; (5) facies and upscaling issues; (6) wireline log interpretation algorithms; and (7) providing a web-accessible database of advanced rock properties. The following text

  13. Role of organic matter fractions in the Montney tight gas reservoir quality

    Science.gov (United States)

    Sanei, Hamed; Wood, James M.; Haeri Ardakani, Omid; Clarkson, Chris R.

    2015-04-01

    This study presents a new approach in Rock-Eval analysis to quantify various organic matter fractions in unconventional reservoirs. The results of study on core samples from the Triassic Montney Formation tight gas reservoir in the Western Canadian Sedimentary Basin show that operationally-defined S1 and S2 hydrocarbon peaks from conventional Rock-Eval analysis may not adequately characterize the organic constituents of unconventional reservoir rocks. Modification of the thermal recipe for Rock-Eval analysis, in conjunction with manual peak integration, provides important information with significance for the evaluation of reservoir quality. An adapted Rock-Eval method, herein called the extended slow heating (ESH) cycle, was developed in which the heating rate was slowed to 10°C per minute over an extended temperature range (150 to 650°C). For Montney core samples from the wet gas window, this method provided quantitative distinctions between major organic matter components of the rock. We show that the traditional S1 and S2 peaks can now be quantitatively divided into three components: (S1ESH) free light oil, (S2a ESH) condensed hydrocarbon residue (CHCR), and (S2b ESH + residual carbon) solid bitumen (refractory, consolidated bitumen/pyrobitumen). The majority of the total organic carbon (TOC) in the studied Montney core samples consists of solid bitumen that represents a former liquid oil phase which migrated into the larger paleo-intergranular pore spaces. Subsequent physicochemical changes to the oil environment led to the precipitation of asphaltene aggregates. Further diagenetic and thermal maturity processes consolidated these asphaltene aggregates into "lumps" of solid bitumen (or pyrobitumen at higher thermal maturity). Solid bitumen obstructs porosity and hinders fluid flow, and thus shows strong negative correlations with reservoir qualities such as porosity and pore throat size. We also find a strong positive correlation between the quantities of

  14. Diagenetic fluids evolution and genetic mechanism of tight sandstone gas reservoirs in Upper Triassic Xujiahe Formation in Sichuan Basin, China

    Institute of Scientific and Technical Information of China (English)

    ZHU RuKai; ZOU CaiNeng; ZHANG Nai; WANG XueSong; CHENG Rong; LIU LiuHong; ZHOU ChuanMin; SONG LiHong

    2008-01-01

    The reservoirs of the Upper Triassic Xujiahe Formation in Sichuan Basin have the characteristics of low compositional maturity, low contents of cements and medium textural maturity.The general physical properties of the reservoirs are poor, with low porosity and low permeability, and there are only a few reservoirs with medium porosity and low permeability in local areas.Based on the diagenetic mineral association, a diagenetic sequence of cements is established: early calcites (or micrite siderites)→ first quartz overgrowth→chlorite coatings→dissolution of feldspars and debris→chlorite linings→ second quartz overgrowth (quartz widen or filled in remain intergranular pores and solution pores→ dissolution→third quartz overgrowth (quartz filled in intergranular and intragranular solution pores)→ intergrowth (ferro) calcites→dolomites→ferro (calcites) dolomites→later dissolution→veins of quartz and calcites formation.Mechanical compaction is the main factor in making the reservoirs tight in the basin, followed by the second and third quartz overgrowth.In a long-term closed system, only feldspars and some lithic fragments are dissolved by diagenetic fluids, while intergranular cements such as quartz and calcit are not dissolved and thus have little influence on the porosity of the Xujiahe Formation.This is the third factor that may have kept the sandstones of Xujiahe Formation tight finally.The hydrocarbon was extensively generated from organic materials after the second quartz overgrowth, and selectively entered favorable reservoirs to form tight sandstone gas reservoirs.

  15. Diagenetic fluids evolution and genetic mechanism of tight sandstone gas reservoirs in Upper Triassic Xujiahe Formation in Sichuan Basin, China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The reservoirs of the Upper Triassic Xujiahe Formation in Sichuan Basin have the characteristics of low compositional maturity, low contents of cements and medium textural maturity. The general physical properties of the reservoirs are poor, with low porosity and low permeability, and there are only a few reservoirs with medium porosity and low permeability in local areas. Based on the diagenetic mineral association, a diagenetic sequence of cements is established: early calcites (or micrite siderites) →first quartz overgrowth→chlorite coatings→dissolution of feldspars and debris→chlorite linings→ second quartz overgrowth (quartz widen or filled in remain intergranular pores and solution pores)→dissolution→third quartz overgrowth (quartz filled in intergranular and intragranular solution pores)→intergrowth (ferro) calcites→dolomites→ferro (calcites) dolomites→later dissolution→veins of quartz and calcites formation. Mechanical compaction is the main factor in making the reservoirs tight in the basin, followed by the second and third quartz overgrowth. In a long-term closed system, only feld-spars and some lithic fragments are dissolved by diagenetic fluids, while intergranular cements such as quartz and calcit are not dissolved and thus have little influence on the porosity of the Xujiahe Formation. This is the third factor that may have kept the sandstones of Xujiahe Formation tight finally. The hydrocarbon was extensively generated from organic materials after the second quartz overgrowth, and selectively entered favorable reservoirs to form tight sandstone gas reservoirs.

  16. Energy Return on Energy Invested for Tight Gas Wells in the Appalachian Basin, United States of America

    Directory of Open Access Journals (Sweden)

    Bryan Sell

    2011-10-01

    Full Text Available The energy cost of drilling a natural gas well has never been publicly addressed in terms of the actual fuels and energy required to generate the physical materials consumed in construction. Part of the reason for this is that drilling practices are typically regarded as proprietary; hence the required information is difficult to obtain. We propose that conventional tight gas wells that have marginal production characteristics provide a baseline for energy return on energy invested (EROI analyses. To develop an understanding of baseline energy requirements for natural gas extraction, we examined production from a mature shallow gas field composed of vertical wells in Pennsylvania and materials used in the drilling and completion of individual wells. The data were derived from state maintained databases and reports, personal experience as a production geologist, personal interviews with industry representatives, and literature sources. We examined only the “upstream” energy cost of providing gas and provide a minimal estimate of energy cost because of uncertainty about some inputs. Of the materials examined, steel and diesel fuel accounted for more than two-thirds of the energy cost for well construction. Average energy cost per foot for a tight gas well in Indiana County is 0.59 GJ per foot. Available production data for this natural gas play was used to calculate energy return on energy invested ratios (EROI between 67:1 and 120:1, which depends mostly on the amount of materials consumed, drilling time, and highly variable production. Accounting for such inputs as chemicals used in well treatment, materials used to construct drill bits and drill pipe, post-gathering pipeline construction, and well completion maintenance would decrease EROI by an unknown amount. This study provides energy constraints at the single-well scale for the energy requirements for drilling in geologically simple systems. The energy and monetary costs of wells from

  17. Advancing New 3D Seismic Interpretation Methods for Exploration and Development of Fractured Tight Gas Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    James Reeves

    2005-01-31

    In a study funded by the U.S. Department of Energy and GeoSpectrum, Inc., new P-wave 3D seismic interpretation methods to characterize fractured gas reservoirs are developed. A data driven exploratory approach is used to determine empirical relationships for reservoir properties. Fractures are predicted using seismic lineament mapping through a series of horizon and time slices in the reservoir zone. A seismic lineament is a linear feature seen in a slice through the seismic volume that has negligible vertical offset. We interpret that in regions of high seismic lineament density there is a greater likelihood of fractured reservoir. Seismic AVO attributes are developed to map brittle reservoir rock (low clay) and gas content. Brittle rocks are interpreted to be more fractured when seismic lineaments are present. The most important attribute developed in this study is the gas sensitive phase gradient (a new AVO attribute), as reservoir fractures may provide a plumbing system for both water and gas. Success is obtained when economic gas and oil discoveries are found. In a gas field previously plagued with poor drilling results, four new wells were spotted using the new methodology and recently drilled. The wells have estimated best of 12-months production indicators of 2106, 1652, 941, and 227 MCFGPD. The latter well was drilled in a region of swarming seismic lineaments but has poor gas sensitive phase gradient (AVO) and clay volume attributes. GeoSpectrum advised the unit operators that this location did not appear to have significant Lower Dakota gas before the well was drilled. The other three wells are considered good wells in this part of the basin and among the best wells in the area. These new drilling results have nearly doubled the gas production and the value of the field. The interpretation method is ready for commercialization and gas exploration and development. The new technology is adaptable to conventional lower cost 3D seismic surveys.

  18. Pulse gas alignment and AFM manipulation of single-wall carbon nanotube

    Institute of Scientific and Technical Information of China (English)

    TIAN XiaoJun; WANG YueChao; XI Ning; DONG ZaiLi; TUNG Steve

    2008-01-01

    In the fabrication process of nanoelectronic device arrays based on single-wall carbon nanotube (SWCNT), oriented alignment of SWCNTs and property modification of metallic SWCNTs in the array are the key problems to be solved. Pulse gas alignment with substrate downward tilt is proposed to realize the controllable alignment of SWCNTs. Experimental results demonstrate that 84% SWCNTs are aligned in -15°- 15° angular to the pulse gas direction. A modified nanomanipulation technology based on atomic force microscope (AFM) is utilized to perform various kinds of SWCNT manipulation, such as SWCNT separation from the "Y" CNT, catalyst removal from the SWCNT end, continual nano buckles fabrication on SWCNT and even stretching to break, which provides a feasible way to modify the size, shape and the electrical property of SWCNTs.

  19. 低渗致密气藏、凝析气藏开发难点与对策%Difficulties and Measures for Development of Low Permeability Tight Gas Reservoirs and Condensate Gas Reservoirs

    Institute of Scientific and Technical Information of China (English)

    李士伦; 孙雷; 杜建芬

    2004-01-01

    Low permeability tight gas reservoirs and condensate gas reservoirs account for a rather high proportion ofdomestic gas reserves, but many of them have low productivity. So it is significant to develop these reservoirs effi-ciently for continuous and stable development of China′s petroleum industry. Around the problems of the developmentof deep low permeability tight gas reservoirs and condensate gas reservoirs, this paper makes an analysis on the geo-logic and development characteristics of these reservoirs and presents ten proper technologies. Finally, five technicalmeasures for the development of such gas reservoirs are proposed in detail. These are deep fracturing technology,treatment technology of accumulated liquids in condensate gas well and near well bore, gas injection technology whenthe formation pressure is lower than the maximum condensate pressure, phase behavior analysis technology in porousmedia of low permeability tight condensate gas reservoir and other gas reservoir engineering technologies.

  20. Assessment of potential shale oil and tight sandstone gas resources of the Assam, Bombay, Cauvery, and Krishna-Godavari Provinces, India, 2013

    Science.gov (United States)

    Klett, Timothy R.; Schenk, Christopher J.; Wandrey, Craig J.; Brownfield, Michael E.; Charpentier, Ronald R.; Tennyson, Marilyn E.; Gautier, Donald L.

    2014-01-01

    Using a well performance-based geologic assessment methodology, the U.S. Geological Survey estimated a technically recoverable mean volume of 62 million barrels of oil in shale oil reservoirs, and more than 3,700 billion cubic feet of gas in tight sandstone gas reservoirs in the Bombay and Krishna-Godavari Provinces of India. The term “provinces” refer to geologically defined units assessed by the USGS for the purposes of this report and carries no political or diplomatic connotation. Shale oil and tight sandstone gas reservoirs were evaluated in the Assam and Cauvery Provinces, but these reservoirs were not quantitatively assessed.

  1. Alignment of graphene oxide nanostructures between microgap electrodes via dielectrophoresis for hydrogen gas sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Budhi; Wang, Jianwei; Rathi, Servin; Kim, Gil-Ho, E-mail: ghkim@skku.edu [School of Electronic and Electrical Engineering and Sungkyunkwan Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-05-18

    Graphene oxide (GO) nanostructures have been aligned between conducting electrodes via dielectrophoresis (DEP) with different electrical configurations. The arrangement of ground with respect to peak-to-peak voltage (V{sub pp}) plays a crucial role in manipulating the GO nanostructures. Grounds on both sides of the V{sub pp} electrode give an excellent linking of GO nanostructures which is explained by scanning electron microscopy and current-voltage characteristics. A finite element method simulation explains the electric field and voltage variation profile during DEP process. The optimized aligned GO nanostructures are used as hydrogen gas sensor with a sensitivity of 6.0% for 800 ppm hydrogen gas.

  2. Alignment of graphene oxide nanostructures between microgap electrodes via dielectrophoresis for hydrogen gas sensing applications

    Science.gov (United States)

    Singh, Budhi; Wang, Jianwei; Rathi, Servin; Kim, Gil-Ho

    2015-05-01

    Graphene oxide (GO) nanostructures have been aligned between conducting electrodes via dielectrophoresis (DEP) with different electrical configurations. The arrangement of ground with respect to peak-to-peak voltage (Vpp) plays a crucial role in manipulating the GO nanostructures. Grounds on both sides of the Vpp electrode give an excellent linking of GO nanostructures which is explained by scanning electron microscopy and current-voltage characteristics. A finite element method simulation explains the electric field and voltage variation profile during DEP process. The optimized aligned GO nanostructures are used as hydrogen gas sensor with a sensitivity of 6.0% for 800 ppm hydrogen gas.

  3. Naturally fractured tight gas reservoir detection optimization. Quarterly report, January 1 - March 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The objective is to determine methods for detection and mapping of naturally fractured systems for economic production of natural gas from fractured reservoirs. This report contains: 3D P-wave alternate processing; down hole 3C geophone analysis; fracture pattern analysis of the Fort Union and Wind River Basin; 3D-3C seismic processing; and technology transfer.

  4. Aligning corporate greenhouse-gas emissions targets with climate goals

    NARCIS (Netherlands)

    Krabbe, Oskar; Linthorst, Giel; Blok, Kornelis; Crijns-Graus, Wina; Vuuren, Van Detlef P.; Höhne, Niklas; Faria, Pedro; Aden, Nate; Pineda, Alberto Carrillo

    2015-01-01

    Corporate climate action is increasingly considered important in driving the transition towards a low-carbon economy. For this, it is critical to ensure translation of global goals to greenhouse-gas (GHG) emissions reduction targets at company level. At the moment, however, there is a lack of cle

  5. Strongly aligned gas-phase molecules at Free-Electron Lasers

    CERN Document Server

    Kierspel, Thomas; Mullins, Terry; Robinson, Joseph; Aquila, Andy; Barty, Anton; Bean, Richard; Boll, Rebecca; Boutet, Sébastien; Bucksbaum, Philip; Chapman, Henry N; Christensen, Lauge; Fry, Alan; Hunter, Mark; Koglin, Jason E; Liang, Mengning; Mariani, Valerio; Morgan, Andrew; Natan, Adi; Petrovic, Vladimir; Rolles, Daniel; Rudenko, Artem; Schnorr, Kirsten; Stapelfeldt, Henrik; Stern, Stephan; Thøgersen, Jan; Yoon, Chun Hong; Wang, Fenglin; Trippel, Sebastian; Küpper, Jochen

    2015-01-01

    We demonstrate a novel experimental implementation to strongly align molecules at full repetition rates of free-electron lasers. We utilized the available in-house laser system at the coherent x-ray imaging beamline at the Linac Coherent Light Source. Chirped laser pulses, i. e., the direct output from the regenerative amplifier of the Ti:Sa chirped pulse amplification laser system, were used to strongly align 2,5-diiodothiophene molecules in a molecular beam. The alignment laser pulses had pulse energies of a few mJ and a pulse duration of 94 ps. A degree of alignment of $\\left$ = 0.85 was measured, limited by the intrinsic temperature of the molecular beam rather than by the available laser system. With the general availability of synchronized chirped-pulse-amplified near-infrared laser systems at short-wavelength laser facilities, our approach allows for the universal preparation of molecules tightly fixed in space for experiments with x-ray pulses.

  6. Imaging molecular structure through femtosecond photoelectron diffraction on aligned and oriented gas-phase molecules.

    Science.gov (United States)

    Boll, Rebecca; Rouzée, Arnaud; Adolph, Marcus; Anielski, Denis; Aquila, Andrew; Bari, Sadia; Bomme, Cédric; Bostedt, Christoph; Bozek, John D; Chapman, Henry N; Christensen, Lauge; Coffee, Ryan; Coppola, Niccola; De, Sankar; Decleva, Piero; Epp, Sascha W; Erk, Benjamin; Filsinger, Frank; Foucar, Lutz; Gorkhover, Tais; Gumprecht, Lars; Hömke, André; Holmegaard, Lotte; Johnsson, Per; Kienitz, Jens S; Kierspel, Thomas; Krasniqi, Faton; Kühnel, Kai-Uwe; Maurer, Jochen; Messerschmidt, Marc; Moshammer, Robert; Müller, Nele L M; Rudek, Benedikt; Savelyev, Evgeny; Schlichting, Ilme; Schmidt, Carlo; Scholz, Frank; Schorb, Sebastian; Schulz, Joachim; Seltmann, Jörn; Stener, Mauro; Stern, Stephan; Techert, Simone; Thøgersen, Jan; Trippel, Sebastian; Viefhaus, Jens; Vrakking, Marc; Stapelfeldt, Henrik; Küpper, Jochen; Ullrich, Joachim; Rudenko, Artem; Rolles, Daniel

    2014-01-01

    This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray free-electron laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C(8)H(5)F) and dissociating, laser-aligned 1,4-dibromobenzene (C(6)H(4)Br(2)) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.

  7. Analysis of tight gas well production histories in the Rocky Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Hale, B.W.

    1986-07-01

    Monthly production records on more than 6,000 gas wells are analyzed to determine expected behavior of additional wells and to compare actual performance with theoretical performance is described by many authors. The wells analyzed in the Rocky Mountains, ranging from the Green River basin of Wyoming to the San Juan basin in New Mexico. Most of these wells produce from low-permeability reservoirs and have been hydraulically fractured. Production trends are studied with three different techniques: conventional semilog rate vs. time analysis, logarithmic rate vs. time analysis, and linear flow decline-curve analysis. The primary purpose of this study is to forecast future rates and reserves. The impact of well downtime and pressure variations in observed flow rates is reviewed.

  8. Tight sand gas development technologies and practices in China%中国致密砂岩气开发工程技术与实践

    Institute of Scientific and Technical Information of China (English)

    马新华; 贾爱林; 谭健; 何东博

    2012-01-01

    Tight sand gas is the main type of unconventional natural gas. According to the geologic characteristics of large-scale tight sandstone gas reservoirs discovered in China in recent years, tight sand gas reservoirs can be classified into three main types, multi-layer lens overlaid tight sand gas reservoir, multilayered tight sandstone gas reservoir and massive tight sand gas reservoir. A series of development technologies for the first 2 types of reservoirs have been formed, focusing on improving individual well producing rate and reducing development cost. They drive the scale development of tight gas. As to multi-layer lens overlaid tight sand gas, the specific technologies include well location optimization, multi-stage sand fracturing, down hole choking and low-pressure surface gas gathering system. As to multilayered tight sand gas, the specific technologies include sweet-spot prediction and evaluation, integrated horizontal well development technique, and drainage gas recovery technique. There are still great challenges in tight gas development from several aspects, such as the enhancement of reserve deployment ratio and recovery ratio, the improvement of individual well producing rate, the development of new and difficult-to-produce reserves as well as the rate maintenance, and gas well management in its later stage of life cycle.%致密砂岩气是非常规天然气的主要类型.根据中国近年来发现的大型致密砂岩气藏的开发地质特征,可划分为3种主要类型:透镜体多层叠置致密砂岩气、多层状致密砂岩气及块状致密砂岩气.前2种类型以提高单井产量、降低开发成本为技术目标形成了系列开发技术,推动了致密气的规模化发展.针对透镜体多层叠置致密砂岩气,形成了以优化布井、多级加砂压裂、井下节流与低压地面集输为特点的开发技术.针对多层状致密砂岩气,形成了以富集区预测与评价、水平井整体开发和排水采气为

  9. Naturally fractured tight gas reservoir detection optimization. Annual report, September 1993--September 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-10-01

    This report is an annual summarization of an ongoing research in the field of modeling and detecting naturally fractured gas reservoirs. The current research is in the Piceance basin of Western Colorado. The aim is to use existing information to determine the most optimal zone or area of fracturing using a unique reaction-transport-mechanical (RTM) numerical basin model. The RTM model will then subsequently help map subsurface lateral and vertical fracture geometries. The base collection techniques include in-situ fracture data, remote sensing, aeromagnetics, 2-D seismic, and regional geologic interpretations. Once identified, high resolution airborne and spaceborne imagery will be used to verify the RTM model by comparing surficial fractures. If this imagery agrees with the model data, then a further investigation using a three-dimensional seismic survey component will be added. This report presents an overview of the Piceance Creek basin and then reviews work in the Parachute and Rulison fields and the results of the RTM models in these fields.

  10. Aligning corporate greenhouse-gas emissions targets with climate goals

    Science.gov (United States)

    Krabbe, Oskar; Linthorst, Giel; Blok, Kornelis; Crijns-Graus, Wina; van Vuuren, Detlef P.; Höhne, Niklas; Faria, Pedro; Aden, Nate; Pineda, Alberto Carrillo

    2015-12-01

    Corporate climate action is increasingly considered important in driving the transition towards a low-carbon economy. For this, it is critical to ensure translation of global goals to greenhouse-gas (GHG) emissions reduction targets at company level. At the moment, however, there is a lack of clear methods to derive consistent corporate target setting that keeps cumulative corporate GHG emissions within a specific carbon budget (for example, 550-1,300 GtCO2 between 2011 and 2050 for the 2 °C target). Here we propose a method for corporate emissions target setting that derives carbon intensity pathways for companies based on sectoral pathways from existing mitigation scenarios: the Sectoral Decarbonization Approach (SDA). These company targets take activity growth and initial performance into account. Next to target setting on company level, the SDA can be used by companies, policymakers, investors or other stakeholders as a benchmark for tracking corporate climate performance and actions, providing a mechanism for corporate accountability.

  11. Imaging Molecular Structure through Femtosecond Photoelectron Diffraction on Aligned and Oriented Gas-Phase Molecules

    CERN Document Server

    Boll, R; Adolph, M; Anielski, D; Aquila, A; Bari, S; Bomme, C; Bostedt, C; Bozek, J D; Chapman, H N; Christensen, L; Coffee, R; Coppola, N; De, S; Decleva, P; Epp, S W; Erk, B; Filsinger, F; Foucar, L; Gorkhover, T; Gumprecht, L; Hoemke, A; Holmegaard, L; Johnsson, P; Kienitz, J S; Kierspel, T; Krasniqi, F; Kuehnel, K -U; Maurer, J; Messerschmidt, M; Moshammer, R; Mueller, Nele L M; Rudek, B; Savelyev, E; Schlichting, I; Schmidt, C; Scholz, F; Schorb, S; Schulz, J; Seltmann, J; Stener, M; Stern, S; Techert, S; Thogersen, J; Trippel, S; Viefhaus, J; Vrakking, M; Stapelfeldt, H; Kuepper, J; Ullrich, J; Rudenko, A; Rolles, D

    2014-01-01

    This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray Free-Electron Laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C8H5F) and dissociating, laseraligned 1,4-dibromobenzene (C6H4Br2) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.

  12. Collective Behavior of a Spin-Aligned Gas of Interwell Excitons in Double Quantum Wells

    DEFF Research Database (Denmark)

    Larionov, A. V.; Bayer, M.; Hvam, Jørn Märcher;

    2005-01-01

    The kinetics of a spin-aligned gas of interwell excitons in GaAs/AlGaAs double quantum wells (n–i–n heterostructure) is studied. The temperature dependence of the spin relaxation time for excitons, in which a photoexcited electron and hole are spatially separated between two adjacent quantum wells...... is associated with indirect evidence of the coherence of the collective phase of interwell excitons at temperatures below the critical value....

  13. Design philosophy and practice of asymmetrical 3D fracturing and random fracturing: A case study of tight sand gas reservoirs in western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Jianchun Guo

    2015-03-01

    Full Text Available At present two technical models are commonly taken in tight gas reservoir stimulation: conventional massive fracturing and SRV fracturing, but how to select a suitable fracturing model suitable for reservoir characteristics is still a question waiting to be answered. In this paper, based on the analysis of geological characteristics and seepage mechanism of tight gas and shale gas reservoirs, the differences between stimulation philosophy of tight gas reservoirs and shale reservoirs are elucidated, and the concept that a suitable stimulation model should be selected based on reservoir geological characteristics and seepage mechanism aiming at maximally improving the seepage capability of a reservoir. Based on this concept, two fracturing design methods were proposed for two tight gas reservoirs in western Sichuan Basin: asymmetrical 3D fracturing design (A3DF for the middle-shallow Upper Jurassic Penglaizhen Fm stacked reservoirs in which the hydraulic fractures can well match the sand spatial distribution and seepage capability of the reservoirs; SRV fracturing design which can increase fracture randomness in the sandstone and shale laminated reservoirs for the 5th Member of middle-deep Upper Triassic Xujiahe Fm. Compared with that by conventional fracturing, the average production of horizontal wells fractured by A3DF increased by 41%, indicating that A3DF is appropriate for gas reservoir development in the Penglaizhen Fm; meanwhile, the average production per well of the 5th Member of the Xujiahe Fm was 2.25 × 104 m3/d after SRV fracturing, showing that the SRV fracturing is a robust technical means for the development of this reservoir.

  14. Possibility of tight sand gas reservoirs in Jixi Basin%鸡西盆地致密砂岩气存在的可能性

    Institute of Scientific and Technical Information of China (English)

    王伟明; 卢双舫; 王世辉; 刘世恩; 王贵磊; 穆国栋; 蒋思芹; 徐建军

    2012-01-01

    Jixi Basin is still immature in petroleum exploration,especially for tight sand gas. Based on summarizing accumulation conditions of tight sand gas reservoirs at home and abroad, we discussed the tight sand gas accumulation conditions in Jixi Basin in respects of structure, source rock and reservoir. According to the geoche-mical data of the dark mudstone samples of Ji D8 well,the tight sand gas resources was estimated by the method of chemical kinetics. The results show that Jixi Basin is a small rifted basin featuring in multiple-cyclic tectonic evolution and rapid deposition. Its tight gas geological conditions are quite different from the large tight sand gas reservoirs in North America. However, large-scale coalbeds in the Chengzihe Formation in Jixi Basin provide abundant gas source for the tight sand gas reservoirs. Superimposition and closely contact of source rocks and reservoir are also in favor of the migration and accumulation of gas. Sweet spots of tight sand gas may exist in the tectonically stable region of the central depression in Jixi Basin.%鸡西盆地的油气勘探程度较低,尤其是对致密砂岩气的研究尚处于起步阶段.在总结国内外成功地区致密砂岩气成藏条件的基础上,从构造、烃源岩以及储层条件等方面探讨了鸡西盆地致密砂岩气的成藏条件.依据鸡D8井暗色泥岩样品的地球化学资料,使用化学动力学法计算了研究区致密砂岩气的资源量.研究表明,鸡西盆地属于小型断陷盆地,多期构造演化与储层快速沉积等特点,决定了研究区不具备类似北美阿尔伯达等成功地区的大型致密砂岩气成藏的地质条件.但鸡西盆地城子河组大规模发育的煤系地层长期生气,为致密砂岩气藏的形成提供了充足的气源,烃源岩与储集层紧密叠置接触也有利于致密气的运移和保存.在鸡西盆地的中央凹陷构造稳定区域,寻找致密储层的甜点区,将有机会获得致密砂岩气藏的勘探突破.

  15. Improving the Availability and Delivery of Critical Information for Tight Gas Resource Development in the Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Mary Behling; Susan Pool; Douglas Patchen; John Harper

    2008-12-31

    To encourage, facilitate and accelerate the development of tight gas reservoirs in the Appalachian basin, the geological surveys in Pennsylvania and West Virginia collected widely dispersed data on five gas plays and formatted these data into a large database that can be accessed by individual well or by play. The database and delivery system that were developed can be applied to any of the 30 gas plays that have been defined in the basin, but for this project, data compilation was restricted to the following: the Mississippian-Devonian Berea/Murrysville sandstone play and the Upper Devonian Venango, Bradford and Elk sandstone plays in Pennsylvania and West Virginia; and the 'Clinton'/Medina sandstone play in northwestern Pennsylvania. In addition, some data were collected on the Tuscarora Sandstone play in West Virginia, which is the lateral equivalent of the Medina Sandstone in Pennsylvania. Modern geophysical logs are the most common and cost-effective tools for evaluating reservoirs. Therefore, all of the well logs in the libraries of the two surveys from wells that had penetrated the key plays were scanned, generating nearly 75,000 scanned e-log files from more than 40,000 wells. A standard file-naming convention for scanned logs was developed, which includes the well API number, log curve type(s) scanned, and the availability of log analyses or half-scale logs. In addition to well logs, other types of documents were scanned, including core data (descriptions, analyses, porosity-permeability cross-plots), figures from relevant chapters of the Atlas of Major Appalachian Gas Plays, selected figures from survey publications, and information from unpublished reports and student theses and dissertations. Monthly and annual production data from 1979 to 2007 for West Virginia wells in these plays are available as well. The final database also includes digitized logs from more than 800 wells, sample descriptions from more than 550 wells, more than 600

  16. The RealGas and RealGasH2O Options of the TOUGH+ Code for the Simulation of Coupled Fluid and Heat Flow in Tight/Shale Gas Systems

    Energy Technology Data Exchange (ETDEWEB)

    Moridis, George; Freeman, Craig

    2013-09-30

    We developed two new EOS additions to the TOUGH+ family of codes, the RealGasH2O and RealGas . The RealGasH2O EOS option describes the non-isothermal two-phase flow of water and a real gas mixture in gas reservoirs, with a particular focus in ultra-tight (such as tight-sand and shale gas) reservoirs. The gas mixture is treated as either a single-pseudo-component having a fixed composition, or as a multicomponent system composed of up to 9 individual real gases. The RealGas option has the same general capabilities, but does not include water, thus describing a single-phase, dry-gas system. In addition to the standard capabilities of all members of the TOUGH+ family of codes (fully-implicit, compositional simulators using both structured and unstructured grids), the capabilities of the two codes include: coupled flow and thermal effects in porous and/or fractured media, real gas behavior, inertial (Klinkenberg) effects, full micro-flow treatment, Darcy and non-Darcy flow through the matrix and fractures of fractured media, single- and multi-component gas sorption onto the grains of the porous media following several isotherm options, discrete and fracture representation, complex matrix-fracture relationships, and porosity-permeability dependence on pressure changes. The two options allow the study of flow and transport of fluids and heat over a wide range of time frames and spatial scales not only in gas reservoirs, but also in problems of geologic storage of greenhouse gas mixtures, and of geothermal reservoirs with multi-component condensable (H2O and CH4) and non-condensable gas mixtures. The codes are verified against available analytical and semi-analytical solutions. Their capabilities are demonstrated in a series of problems of increasing complexity, ranging from isothermal flow in simpler 1D and 2D conventional gas reservoirs, to non-isothermal gas flow in 3D fractured shale gas reservoirs involving 4 types of fractures, micro-flow, non-Darcy flow and gas

  17. Metal-modified and vertically aligned carbon nanotube sensors array for landfill gas monitoring applications

    Energy Technology Data Exchange (ETDEWEB)

    Penza, M; Rossi, R; Alvisi, M [ENEA, Department of Physical Technologies and New Materials, PO Box 51 Br-4, I-72100 Brindisi (Italy); Serra, E, E-mail: michele.penza@enea.it [ENEA, Department of Physical Technologies and New Materials, Via Anguillarese 301, I-00060 Rome (Italy)

    2010-03-12

    Vertically aligned carbon nanotube (CNT) layers were synthesized on Fe-coated low-cost alumina substrates using radio-frequency plasma enhanced chemical vapour deposition (RF-PECVD) technology. A miniaturized CNT-based gas sensor array was developed for monitoring landfill gas (LFG) at a temperature of 150 deg. C. The sensor array was composed of 4 sensing elements with unmodified CNT, and CNT loaded with 5 nm nominally thick sputtered nanoclusters of platinum (Pt), ruthenium (Ru) and silver (Ag). Chemical analysis of multicomponent gas mixtures constituted of CO{sub 2}, CH{sub 4}, H{sub 2}, NH{sub 3}, CO and NO{sub 2} has been performed by the array sensor responses and pattern recognition based on principal component analysis (PCA). The PCA results demonstrate that the metal-decorated and vertically aligned CNT sensor array is able to discriminate the NO{sub 2} presence in the multicomponent mixture LFG. The NO{sub 2} gas detection in the mixture LFG was proved to be very sensitive, e.g.: the CNT:Ru sensor shows a relative change in the resistance of 1.50% and 0.55% for NO{sub 2} concentrations of 3.3 ppm and 330 ppb dispersed in the LFG, respectively, with a wide NO{sub 2} gas concentration range measured from 0.33 to 3.3 ppm, at the sensor temperature of 150 deg. C. The morphology and structure of the CNT networks have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. A forest-like nanostructure of vertically aligned CNT bundles in the multi-walled form appeared with a height of about 10 {mu}m and a single-tube diameter varying in the range of 5-35 nm. The intensity ratio of the Raman spectroscopy D-peak and G-peak indicates the presence of disorder and defects in the CNT networks. The size of the metal (Pt, Ru, Ag) nanoclusters decorating the CNT top surface varies in the range of 5-50 nm. Functional characterization based on electrical charge transfer sensing mechanisms in the metal

  18. Reeling of tight fit pipe

    NARCIS (Netherlands)

    Focke, E.S.

    2007-01-01

    If it would be possible to install Tight Fit Pipe by means of reeling, it would be an attractive new option for the exploitation of offshore oil and gas fields containing corrosive hydrocarbons. Tight Fit Pipe is a mechanically bonded double walled pipe where a corrosion resistant alloy liner pipe i

  19. Development and field application of a 6-bottle serial gas-tight fluid sampler for collecting seafloor cold seep and hydrothermal vent fluids with autonomous operation capability

    Science.gov (United States)

    Wu, S.; Ding, K.; Yang, C.; Seyfried, W. E., Jr.; Tan, C.; Schaen, A. T.; Luhmann, A. J.

    2014-12-01

    A 6-bottle serial gas-tight sampler (so-called "six-shooter") was developed for application with deep-sea vent fluids. The new device is composed of a custom-made 6-channel valve manifold and six sampling bottles which are circularly distributed around the valve manifold. Each valve channel consists of a high-pressure titanium cartridge valve and a motor-driven actuator. A sampling snorkel is connected to the inlet of the manifold that delivers the incoming fluid to different bottles. Each sampling bottle has a 160 ml-volume chamber and an accumulator chamber inside where compressed nitrogen is used to maintain the sample at near in-situ pressure. An electronics chamber that is located at the center of the sampler is used to carry out all sampling operations, autonomously, if desired. The sampler is of a compact circular configuration with a diameter of 26 cm and a length of 54 cm. During the SVC cruise AT 26-12, the sampler was deployed by DSV2 Alvin at a cold seep site MC036 with a depth of 1090 m in the Gulf of Mexico. The sampler collected fluid samples automatically following the tidal cycle to monitor the potential impact of the tide cycle on the fluid chemistry of cold seep in a period of two day. During the cruise AT 26-17, the sampler was used with newly upgraded DSV2 Alvin three times at the hydrothermal vent sites along Axial Seamount and Main Endeavor Field on Juan de Fuca Ridge. During a 4-day deployment at Anemone diffuse site (Axial Caldera), the sampler was set to work in an autonomous mode to collect fluid samples according to the preset interval. During other dives, the sampler was manually controlled via ICL (Inductively Coupled Link) communication through the hull. Gas-tight fluid samples were collected from different hydrothermal vents with temperatures between 267 ℃ and 335 ℃ at the depth up to 2200 m. The field results indicate unique advantages of the design. It can be deployed in extended time period with remote operation or working

  20. The Morphologies and Alignments of Gas, Mass, and the Central Galaxies of CLASH Clusters of Galaxies

    Science.gov (United States)

    Donahue, Megan; Ettori, Stefano; Rasia, Elena; Sayers, Jack; Zitrin, Adi; Meneghetti, Massimo; Voit, G. Mark; Golwala, Sunil; Czakon, Nicole; Yepes, Gustavo; Baldi, Alessandro; Koekemoer, Anton; Postman, Marc

    2016-03-01

    Morphology is often used to infer the state of relaxation of galaxy clusters. The regularity, symmetry, and degree to which a cluster is centrally concentrated inform quantitative measures of cluster morphology. The Cluster Lensing and Supernova survey with Hubble Space Telescope (CLASH) used weak and strong lensing to measure the distribution of matter within a sample of 25 clusters, 20 of which were deemed to be “relaxed” based on their X-ray morphology and alignment of the X-ray emission with the Brightest Cluster Galaxy. Toward a quantitative characterization of this important sample of clusters, we present uniformly estimated X-ray morphological statistics for all 25 CLASH clusters. We compare X-ray morphologies of CLASH clusters with those identically measured for a large sample of simulated clusters from the MUSIC-2 simulations, selected by mass. We confirm a threshold in X-ray surface brightness concentration of C ≳ 0.4 for cool-core clusters, where C is the ratio of X-ray emission inside 100 h70-1 kpc compared to inside 500 {h}70-1 kpc. We report and compare morphologies of these clusters inferred from Sunyaev-Zeldovich Effect (SZE) maps of the hot gas and in from projected mass maps based on strong and weak lensing. We find a strong agreement in alignments of the orientation of major axes for the lensing, X-ray, and SZE maps of nearly all of the CLASH clusters at radii of 500 kpc (approximately 1/2 R500 for these clusters). We also find a striking alignment of clusters shapes at the 500 kpc scale, as measured with X-ray, SZE, and lensing, with that of the near-infrared stellar light at 10 kpc scales for the 20 “relaxed” clusters. This strong alignment indicates a powerful coupling between the cluster- and galaxy-scale galaxy formation processes.

  1. Research on Pressure Tight Sampling Technique of Deep-Sea Shallow Sediment——A New Approach to Gas Hydrate Investigation

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying; QIN Hua-wei; LI Shi-lun; GU Lin-yi; PAN Hua-chen

    2006-01-01

    Analyzed and calculated are pressure changes and body deformation of the sample inside of the corer in the process of sampling of deep-sea shallow sediment with a non-piston corer for gas hydrate investigation. Two conclusions are drawn: (1) the stress increments associated with the corer through the sampling process do not affect the stabilization of the gas hydrate; (2) the body deformation of the sample is serious and the "incremental filling ratio" (IFR) is less than unit. For taking samples with in-situ pressure and structure, combining with the design theories of the pressure tight corer, we have designed a kind of piston corer, named the gas hydrate pressure tight piston corer. Several tests on the sea have been conducted. Test results indicate that the piston corer has a good ability of taking sediment samples on the seafloor and maintaining their original in-situ pressure, meeting the requirement of exploration of gas hydrate in deep-sea shallow sediment layers.

  2. Tight turns

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    The Italian National Institute for Nuclear Physics (INFN) has successfully tested the first model of a new fast-ramping curved dipole magnet. This is great news for CERN, which sees the advance as holding potential for the future of the SPS.   The first model of a new fast-ramping curved dipole magnet being prepared for cryogenic testing at the LASA laboratory (INFN Milano, Italy). On 16 July INFN introduced an innovative dipole magnet. With a length of some 4 metres, it can produce a 4.5 Tesla magnetic field and achieve a tighter bend than ever before (the bending radius has been squeezed to a remarkable 66.7 metres). This new magnet was designed in the first instance for GSI’s SIS300 synchrotron (in Germany), which will require 60 dipoles of this type. "Achieving such a tight bend demanded a major R&D effort," stressed Pasquale Fabbricatore, the spokesman of the INFN collaboration responsible for the magnet’s development. "We had to not o...

  3. Ultrafast electron diffraction from laser-aligned molecules in the gas phase

    Science.gov (United States)

    Yang, Jie

    Ultrafast electron diffraction has emerged since the end of last century, and has become an increasingly important tool for revealing great details of molecular dynamics. In comparison to spectroscopic techniques, ultrafast electron diffraction directly probes time-resolved structure of target molecules, and therefore can potentially provide "molecular movies" of the reactions being studied. These molecular movies are critical for understanding and ultimately controlling the energy conversion pathways and efficiencies of photochemical processes. In this dissertation, I have focused on ultrafast electron diffraction from gas-phase molecules, and have investigated several long-standing challenges that have been preventing researchers from being able to achieve 3-D molecular movies of photochemical reactions. The first challenge is to resolve the full 3-D structure for molecules in the gas phase. The random orientation of molecules in the gas phase smears out the diffraction signal, which results in only 1-D structural information being accessible. The second challenge lies in temporal resolution. In order to resolve coherent nuclear motions on their natural time scale, a temporal resolution of ˜200 femtosecond or better is required. However, due to experimental limitations the shortest temporal resolution that had been achieved was only a few picoseconds in early 2000, by Zewail group from Caltech. The first challenge is tackled by laser-alignment. In the first half of the dissertation, I approach this method both theoretically and experimentally, and demonstrate that by using a short laser pulse to transiently align target molecules in space, 3-D molecular structure can be reconstructed ab-initio from diffraction patterns. The second half of the dissertation presents two experiments, both of which are important steps toward imaging coherent nuclear motions in real time during photochemical reactions. The first experiment simultaneously resolves molecular alignment

  4. Preparation and gas-sensing property of parallel-aligned ZnO nanofibrous films

    Indian Academy of Sciences (India)

    Zikui Bai; Weilin Xu; Changsheng Xie; Mingchao Dong; Shunping Zhang; Jie Xu; Shili Xiao

    2013-08-01

    Parallel-aligned zinc oxide (ZnO) nanofibrous films fabricated by using electrospinning technique were used in gas sensors for the detection of ethanol and formaldehyde. The morphologies and crystal structures of the films were characterized by field-emission scanning electron microscopy (FE–SEM) and X-ray diffraction (XRD), respectively. FE–SEM results showed that ZnO nanofibres had an approximate diameter of 100–300 nm and consisted of hexagonal wurtzite structure ZnO nanocrystals with a primary particle diameter of 20–50 nm. The results of resistance–temperature characteristics and responses to ethanol and formaldehyde indicated that the parallelaligned ZnO nanofibrous film had a low activation energy (0.246 eV), a low optimum operating temperature and a high response. The response and recovery had a high rate in the initial stage and a low rate in the later stage. The parallel-aligned ZnO nanofibrous film had excellent potential application for formaldehyde sensor.

  5. Hydraulic fracture model and diagnostics verification at GRI/DOE multi-site projects and tight gas sand program support. Final report, July 28, 1993--February 28, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, J.E.

    1997-12-31

    The Mesaverde Group of the Piceance Basin in western Colorado has been a pilot study area for government-sponsored tight gas sand research for over twenty years. Early production experiments included nuclear stimulations and massive hydraulic fracture treatments. This work culminated in the US Department of Energy (DOE)`s Multiwell Experiment (MWX), a field laboratory designed to study the reservoir and production characteristics of low permeability sands. A key feature of MWX was an infrastructure which included several closely spaced wells that allowed detailed characterization of the reservoir through log and core analysis, and well testing. Interference and tracer tests, as well as the use of fracture diagnostics gave further information on stimulation and production characteristics. Thus, the Multiwell Experiment provided a unique opportunity for identifying the factors affecting production from tight gas sand reservoirs. The purpose of this operation was to support the gathering of field data that may be used to resolve the number of unknowns associated with measuring and modeling the dimensions of hydraulic fractures. Using the close-well infrastructure at the Multiwell Site near Rifle, Colorado, this operation focused primarily on the field design and execution of experiments. The data derived from the experiments were gathered and analyzed by DOE team contractors.

  6. A realistic transport model with pressure dependent parameters for gas flow in tight porous media with application to determining shale rock properties

    CERN Document Server

    Ali, Iftikhar

    2016-01-01

    Shale gas recovery has seen a major boom in recent years due to the increasing global energy demands; but the extraction technologies are very expensive. It is therefore important to develop realistic transport modelling and simulation methods, for porous rocks and porous media, that can compliment the field work. Here, a new nonlinear transport model for single phase gas flow in tight porous media is derived, incorporating many important physical processes that occur in such porous systems: continuous flow, transition flow, slip flow, Knudsen diffusion, adsorption and desorption in to and out of the rock material, and a correction for high flow rates (turbulence). This produces a nonlinear advection-diffusion type of partial differential equation (PDE) with pressure dependent model parameters and associated compressibility coefficients, and highly nonlinear apparent convective flux (velocity) and apparent diffusivity. An important application is to the determination of shale rock properties, such as porosity...

  7. Reeling of tight fit pipe

    OpenAIRE

    Focke, E.S.

    2007-01-01

    If it would be possible to install Tight Fit Pipe by means of reeling, it would be an attractive new option for the exploitation of offshore oil and gas fields containing corrosive hydrocarbons. Tight Fit Pipe is a mechanically bonded double walled pipe where a corrosion resistant alloy liner pipe is mechanically fitted inside a carbon steel outer pipe through a thermo-hydraulic manufacturing process. Reeling is a fast method of offshore pipeline installation where a pipe is spooled on a reel...

  8. The characteristics of gravity and magnetic fields and the distribution of tight sandstone gas in the eastern Ordos Basin, China

    Science.gov (United States)

    Yuan, Bingqiang; Zhang, Huaan; Zhang, Chunguan; Xu, Haihong; Yan, Yunkui

    2016-04-01

    In order to perform gas exploration and determine the distribution pattern of gas in the Yanchang Oil Field in the eastern part of the North Shaanxi Slope, Ordos Basin, China, gravity and magnetic survey data were systemically collated, processed and interpreted in combination with the drilling data and recent seismic data. The genesis of gravity and magnetic anomalies and the relationship between the characteristics of the gravity and magnetic fields and known gas distribution were explored in order to predict the favourable exploration targets for gas. Gravity anomalies resulted both from the lateral variation in density of the basement rock and lateral lithologic transformation in the sedimentary cover. The regional magnetic anomalies were mainly caused by the basement metamorphic rocks and the residual magnetic anomalies may reflect the amount and general location of the volcanic materials in the overlying strata. The residual gravity and magnetic anomalies generated by high-density sandstone and high content of volcanics in the gas reservoir of the upper Paleozoic distorted and deformed the anomaly curves when they were stacked onto the primary background anomaly. The gas wells were generally found to be located in the anomaly gradient zones, or the distorted part of contour lines, and the flanks of high and low anomalies, or the transitional zones between anomaly highs and lows. The characteristics of gravity and magnetic fields provide significant information that can be used for guidance when exploring the distribution of gas. Based on these characteristics, five favourable areas for gas exploration were identified; these are quasi-equally spaced like a strip extending from the southeast to the northwest.

  9. Can there be additional rocky planets in the Habitable Zone of tight binary stars with a known gas giant?

    CERN Document Server

    Funk, Barbara; Eggl, Siegfried

    2015-01-01

    Locating planets in HabitableZones (HZs) around other stars is a growing field in contemporary astronomy. Since a large percentage of all G-M stars in the solar neighbourhood are expected to be part of binary or multiple stellar systems, investigations of whether habitable planets are likely to be discovered in such environments are of prime interest to the scientific community. As current exoplanet statistics predicts that the chances are higher to find new worlds in systems that are already known to have planets, we examine four known extrasolar planetary systems in tight binaries in order to determine their capacity to host additional habitable terrestrial planets. Those systems are Gliese 86, gamma Cephei, HD 41004 and HD 196885. In the case of gamma Cephei, our results suggest that only the M dwarf companion could host additional potentially habitable worlds. Neither could we identify stable, potentially habitable regions around HD 196885 A. HD 196885 B can be considered a slightly more promising target ...

  10. Aqueous Capillary Imbibition Behavior Management in Fractured Tight Gas Reservoirs%裂缝性致密砂岩气藏水相毛管自吸调控

    Institute of Scientific and Technical Information of China (English)

    游利军; 康毅力

    2013-01-01

    钻井、完井、增产改造工作液滤液、边底水或凝析水在井筒或裂缝面附近发生毛管自吸行为和滞留效应诱发水相圈闭损害,妨碍气藏的及时发现、准确评价和经济开发.以我国四川、鄂尔多斯盆地典型致密砂岩气藏为例,基于致密气藏天然气产出机理,分析了致密气藏经济开发的水平井钻井完井、水力压裂、采气等作业环节中水相自吸过程及其对作业效果的影响.钻井完井过程中水相快速自吸进入基块,驱替出非润湿相油气,打破裂缝壁面力学—化学平衡,诱发井壁失稳;进入裂缝的工作液要快速返排,以免自吸侵入基块降低基块—裂缝传质效率;裂缝中水相高速流动,不易毛管自吸进入基块,造成边底水沿裂缝快速推进,造成水淹.矿场工程技术实践证明,裂缝致密气藏勘探开发全过程,选用合理水基工作流体体系,改善采气工艺措施,调控毛管自吸,进而达到防治水相圈闭损害的目的,是经济开发致密气藏的关键.%The filtration of drilling, completion and stimulation fluids, edge water and bottom water can spontaneously imbibe into and be blocked in the matrix adjacent to wellbore and fractures, which induces water phase trapping damage, preventing gas reservoir from identification, accurate assessment and economic development. The imbibition phenomena of tight sandstone gas reservoirs in west Sichuan basin and north Ordos basin during horizontal well drilling and completion, hydraulic fracturing and gas production operations are investigated on the basis of the production mechanisms of tight gas. The analysis of effects of well operation exerted by water phase imibibiton indicates that the water rapidly imbibes into matrix and displaces oil and gas, which breaks the chemical and mechanical balance and induces the borehole instability, that working fluids invading into fractures should return as soon as possible in case they imbibe

  11. Peak alignment and robust principal component analysis of gas chromatograms of fatty acid methyl esters and volatiles

    DEFF Research Database (Denmark)

    Frosch, Stina; Jørgensen, Bo

    2007-01-01

    Gas chromatograms of fatty acid methyl esters and of volatile lipid oxidation products from fish lipid extracts are analyzed by multivariate data analysis [principal component analysis (PCA)]. Peak alignment is necessary in order to include all sampled points of the chromatograms in the data set...... that the usage of ROPCA is advantageous, compared with traditional PCA, when analysing the entire profile of chromatographic data in cases of sub-optimally aligned data. It also demonstrates how choosing the most robust PCA (sample or element-wise) depends on the type of outliers present in the data set....

  12. Designing the deep basin development entity : drawing and expanding the boundaries of DE number 2 for enhanced exploitation of Alberta's deep basin tight gas resource

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, B. [Petrel Robertson Consulting Ltd., Calgary, AB (Canada); Conrad, L.; Daniel, S. [EnCana Corp., Calgary, AB (Canada); Dahlin, A. [Shell Canada Ltd., Calgary, AB (Canada)

    2009-07-01

    This presentation examined the feasibility of expanding the boundaries of Deep Basin Development Entity (DE no.2) for enhanced exploitation of Alberta's deep basin tight gas resource. Specifically it presented a review of the development history of the basin and summarized the technical understanding of DE no.2. The presentation also emphasized the success of a collaborative process for regulatory change between the Canadian Association of Petroleum Producers and the Energy Resources Conservation Board. The DE no. 2 is located in the western flank of the western Canada Sedimentary Basin. It facilitates commingling of multiple stacked sands and reduces the regulatory requirements for drilling and completion programs. It was expanded in 2009 to include 464 townships. Gas resource mapping was discussed for several areas and an example was illustrated for the Cadomin Formation, with particular reference to the net porous sand isopach; average porosity; gas saturation; temperature; reservoir pressure; and resource density. The future of DE no. 2 has been identified as one of the priority areas for Alberta regulatory review as that it holds 400 TCF of resource potential. tabs., figs.

  13. Model-based peak alignment of metabolomic profiling from comprehensive two-dimensional gas chromatography mass spectrometry

    Directory of Open Access Journals (Sweden)

    Jeong Jaesik

    2012-02-01

    Full Text Available Abstract Background Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC/TOF-MS has been used for metabolite profiling in metabolomics. However, there is still much experimental variation to be controlled including both within-experiment and between-experiment variation. For efficient analysis, an ideal peak alignment method to deal with such variations is in great need. Results Using experimental data of a mixture of metabolite standards, we demonstrated that our method has better performance than other existing method which is not model-based. We then applied our method to the data generated from the plasma of a rat, which also demonstrates good performance of our model. Conclusions We developed a model-based peak alignment method to process both homogeneous and heterogeneous experimental data. The unique feature of our method is the only model-based peak alignment method coupled with metabolite identification in an unified framework. Through the comparison with other existing method, we demonstrated that our method has better performance. Data are available at http://stage.louisville.edu/faculty/x0zhan17/software/software-development/mspa. The R source codes are available at http://www.biostat.iupui.edu/~ChangyuShen/CodesPeakAlignment.zip. Trial Registration 2136949528613691

  14. 气体钻井应用于致密砂岩气藏开发的思索%DISCUSSION ON TIGHT SANDSTONE GAS RESERVOIR DEVELOPMENT BY GAS DRILLING

    Institute of Scientific and Technical Information of China (English)

    吴志均; 周春梅; 唐红君

    2009-01-01

    致密砂岩气藏是非常重要的非常规油气资源,其储层致密、孔喉细小、黏土改造作用强、强亲水且原始水饱和度低;采用钻井液钻开储层可能造成较为严重损害,且难以解除,严重影响气井产能.气体钻井是保护该类储气层的最有效技术,可以获得高的产能.我国在应用该技术开发致密砂岩气藏中取得较好的效果,但是部分井的效果差,甚至发生井下复杂情况.由于断层、透镜体和裂缝的作用使得气藏非均质性强,为充分发挥气体钻井的优势,应开展气藏精细描述,综合分析储层发育的主控因素,建立高渗富集区分布模式,优选井位和井身轨迹,这是气井高产稳产的物质基础.由于气体钻井与常规钻井有较大差异,需要做好气体钻井的工程可行性论证,气体钻井和完井一体化设计来实现有效保护气层且投产快;并根据其技术特点加强现场组织实施工作,以达到在安全顺利条件下获得高产气量.%Tight sandstone gas reservoir is a very important unconventional petroleum resource. Its characteristics are tight rock, small pore-throat, powerful reforming effects of clay minerals, strong water wettability and low initial water saturation. It is badly damaged and restored difficultly when the reservoir is drilled by drilling fluid, gas well productivity is reduced greatly. Gas drilling is an effective technique of formation damage control, high productivity and good effect are gotten in development of tight sandstone gas reservoir by this technique in China,but the results of some wells are bad, and downhole complex problems are taken place. Tight sandstone gas reservoir has strong nonuniformity, in order to full bring into play the advantage of gas drilling, the fine description of gas reservoir was done, the main controlling factors of reservoir must be analyzed synthetically, the distribution pattern of high permeability and abundance zone is established

  15. Effect of weave tightness and structure on the in-plane and through-plane air permeability of woven carbon fibers for gas diffusion layers

    Energy Technology Data Exchange (ETDEWEB)

    Caston, Terry B.; Murphy, Andrew R.; Harris, Tequila A.L. [Department of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

    2011-01-15

    In this study, woven gas diffusion layers (GDLs) with varying weave type and tightness are investigated. Plain and twill weave patterns were manufactured in-house. The in-plane and through-plane air permeability of the woven samples were tested, and mercury intrusion porosimetry (MIP) tests were performed to study the pore structure. It was found that the twill weave has a higher permeability than the plain weave, which is consistent with literature. Like non-woven carbon papers, woven GDLs have higher in-plane permeability than through-plane permeability; however it has been shown that it is possible to manufacture a GDL with higher through-plane permeability than in-plane permeability. It was also concluded that the percentage of macropores in the weave is the driving factor in determining the through-plane air permeability. This work lays the groundwork for future studies to attempt to characterize the relationship between the weave structure and the air permeability in woven GDLs. (author)

  16. CO emissions from optically selected galaxies at z~0.1-0.2: Tight anti-correlation between molecular gas fraction and 4000 \\AA break strength

    CERN Document Server

    Morokuma-Matsui, Kana; Sorai, Kazuo; Kuno, Nario

    2015-01-01

    We performed 12CO(J=1-0) (hereafter, CO) observations towards 12 normal star-forming galaxies with stellar mass of Mstar=10^10.6-10^11.3 Msun at z=0.1-0.2 with the 45-m telescope at the Nobeyama Radio Observatory (NRO). The samples are selected with Dn(4000) that is a strength of the 4000 \\AA break, instead of commonly used far-infrared (FIR) flux. We successfully detect the CO emissions from eight galaxies with signal-to-noise ratio (S/N) larger than three, demonstrating the effectiveness of the Dn(4000)-based sample selection. For the first time, we find a tight anti-correlation between Dn(4000) and molecular gas fraction (fmol) using literature data of nearby galaxies in which the galaxies with more fuel for star formation have younger stellar populations. We find that our CO-detected galaxies at z~0.1-0.2 also follow the same relation of nearby galaxies. This implies that the galaxies evolve along this Dn(4000)-fmol relation, and that Dn(4000) seems to be used as a proxy for fmol which requires many time-...

  17. CO Emissions from Optically Selected Galaxies at z˜0.1-0.2: Tight Anti-Correlation Between Molecular Gas Fraction and 4000 Angstrom Break Strength

    Science.gov (United States)

    Morokuma-Matsui, K.; Baba, J.; Sorai, K.; Kuno, N.

    2015-12-01

    We performed 12CO(J=1-0) (hereafter, CO) observations towards 12 normal star-forming galaxies with M⋆=1010.6-1011.3 M⊙ at z=0.1-0.2 with the 45-m telescope at the Nobeyama Radio Observatory (NRO). The samples are selected with Dn(4000) that is a measure of the 4000 Angstrom break strength, instead of commonly used far-infrared (FIR) flux. We detect the CO emissions from 8 galaxies with signal-to-noise ratio (S/N) larger than 3, demonstrating the effectiveness of the Dn(4000)-based sample selection. We find a tight anti-correlation between Dn(4000) and molecular gas fraction (fmol) using literature data of nearby galaxies in which the galaxies with more fuel for star formation have younger stellar populations. CO-detected galaxies at z˜0.1-0.2 also follow the same relation of nearby galaxies, implying 1) the galaxies evolve along this Dn(4000)-fmol relation, and 2) Dn(4000) seems to be used as a proxy for fmol which requires many time-consuming observations1.

  18. X-ray diffraction from isolated and strongly aligned gas-phase molecules with a free-electron laser

    CERN Document Server

    Küpper, Jochen; Holmegaard, Lotte; Filsinger, Frank; Rouzée, Arnaud; Rolles, Daniel; Rudenko, Artem; Johnsson, Per; Martin, Andrew V; Adolph, Marcus; Aquila, Andrew; Bajt, Saša; Barty, Anton; Bostedt, Christoph; Bozek, John; Caleman, Carl; Coffee, Ryan; Coppola, Nicola; Delmas, Tjark; Epp, Sascha; Erk, Benjamin; Foucar, Lutz; Gorkhover, Tais; Gumprecht, Lars; Hartmann, Andreas; Hartmann, Robert; Hauser, Günter; Holl, Peter; Hömke, Andre; Kimmel, Nils; Krasniqi, Faton; Kühnel, Kai-Uwe; Maurer, Jochen; Messerschmidt, Marc; Mosshammer, Robert; Reich, Christian; Rudek, Benedikt; Santra, Robin; Schlichting, Ilme; Schmidt, Carlo; Schorb, Sebastian; Schulz, Joachim; Soltau, Heike; Strüder, Lothar; Thøgersen, Jan; Vrakking, Marc J J; Weidenspointner, Georg; White, Thomas A; Wunderer, Cornelia; Meijer, Gerard; Ullrich, Joachim; Stapelfeldt, Henrik; Chapman, Henry N

    2013-01-01

    We report experimental results on x-ray diffraction of quantum-state-selected and strongly aligned ensembles of the prototypical asymmetric rotor molecule 2,5-diiodobenzonitrile using the Linac Coherent Light Source. The experiments demonstrate pioneering steps toward a new bottom-up approach to diffractive imaging of distinct structures of individual, isolated gas-phase molecules. We confirm several key ingredients of single molecule diffraction experiments: the abilities to detect and count individual scattered x-ray photons in single shot diffraction data, to deliver state-selected, e.g., structural-isomer-selected, ensembles of molecules to the x-ray interaction volume, and to strongly align the scattering molecules. Our approach, using ultrashort x-ray pulses, is suitable to study ultrafast dynamics of isolated molecules.

  19. Prime tight frames

    DEFF Research Database (Denmark)

    Lemvig, Jakob; Miller, Christopher; Okoudjou, Kasso A.

    2014-01-01

    to suggest effective analysis and synthesis computation strategies for such frames. Finally, we describe all prime frames constructed from the spectral tetris method, and, as a byproduct, we obtain a characterization of when the spectral tetris construction works for redundancies below two.......We introduce a class of finite tight frames called prime tight frames and prove some of their elementary properties. In particular, we show that any finite tight frame can be written as a union of prime tight frames. We then characterize all prime harmonic tight frames and use thischaracterization...

  20. The alignment and shape of dark matter, stellar, and hot gas distributions in the EAGLE and cosmo-OWLS simulations

    CERN Document Server

    Velliscig, Marco; Schaye, Joop; Bower, Richard G; Crain, Robert A; van Daalen, Marcel P; Vecchia, Claudio Dalla; Frenk, Carlos S; Furlong, Michelle; McCarthy, Ian G; Schaller, Matthieu; Theuns, Tom

    2015-01-01

    We report the alignment and shape of dark matter, stellar, and hot gas distributions in the EAGLE and cosmo-OWLS simulations. The combination of these state-of-the-art hydro-cosmological simulations enables us to span four orders of magnitude in halo mass ($11 < log_{10}(M_{200}/ [h^{-1}M_\\odot]) < 15$), a wide radial range ($-2.3 < log_{10}(r/[h^{-1}Mpc ]) < 1.3$) and redshifts $0 < z < 1$. The shape parameters of the dark matter, stellar and hot gas distributions follow qualitatively similar trends: they become more aspherical (and triaxial) with increasing halo mass, radius and redshift. We measure the misalignment of the baryonic components (hot gas and stars) of galaxies with their host halo as a function of halo mass, radius, redshift, and galaxy type (centrals vs satellites and early- vs late-type). Overall, galaxies align well with local distribution of the total (mostly dark) matter. However, the stellar distributions on galactic scales exhibit a median misalignment of about 45-50 d...

  1. Preparation of aligned nanotube membranes for water and gas separation applications

    Energy Technology Data Exchange (ETDEWEB)

    Lulevich, Valentin; Bakajin, Olgica; Klare, Jennifer E.; Noy, Aleksandr

    2016-01-05

    Fabrication methods for selective membranes that include aligned nanotubes can advantageously include a mechanical polishing step. The nanotubes have their ends closed off during the step of infiltrating a polymer precursor around the nanotubes. This prevents polymer precursor from flowing into the nanotubes. The polishing step is performed after the polymer matrix is formed, and can open up the ends of the nanotubes.

  2. Progress of research on hydrocarbon accumulation of tight sand gas and several issues for concerns%致密砂岩气成藏研究进展及值得关注的几个问题

    Institute of Scientific and Technical Information of China (English)

    郭迎春; 庞雄奇; 陈冬霞; 姜福杰; 汤国民

    2013-01-01

    Continuous tight sand gas is a significant unconventional resource for natural gas .To understand the progress of geological research on this kind of gas reservoir ,this paper summarized the criteria for identification of tight sand reser-voirs,their classification ,geological characteristics ,elements of hydrocarbon accumulation ,and trapping mechanisms .The current criteria for identivation of continuous tight sand gas reservoirs does not take accumulation conditions into conside -ration.The real critical conditions of tight sand gas change along with hydrocarbon accumulation conditions .The key ele-ments of hydrocarbon accumulation in tight gas reservoir involve hydrocarbon source rock ,tight sandstone close to source rock and stable tectonic environment .It should be noted that the nature of tight sandstone is nano-micro scale pore throat and the percentage of pore throats is about the same as that of pores ,and that abnormal pressure is not an essential differ-ence between tight sand gas reservoir and conventional gas reservoir .Several key issues concerning continuous tight sand gas accumulation are presented .The first is study on dynamic trapping mechanism for tight sand gas reservoir ,i.e.the force balance between driving force(gas pressure)and resistance(capillary force,viscous force and formation water pres-sure) at the interface of gas water inversion .The quantitative description and simulation of evolution of these forces are particularly important .The second is the research on the mechanism and process of adjustment of tight sand gas reservoir as well as restoration of the original tight sand gas reservoir .The restoration of the original reservoir can be realized by means of force balance relation at the interface of gas water inversion .All of the late adjustment and modification were realized through changing the critical conditions of gas water inversion .The third is study of the control of sandbodies with relatively high porosity and

  3. 致密砂岩气藏有效厚度确定方法及应用探讨%A Discussion on the Determination Way to Effective Thickness of Tight Sandstone Gas Pools

    Institute of Scientific and Technical Information of China (English)

    胡林楠; 赵靖舟

    2013-01-01

    There is more and more attention being paid to the tight sandstone gas pools which have been the major force of the unconventional petroleum resources. As the tight sandstone gas pools are different from the conventional ones,whose reservoirs are tight,the rock property is bad,and the electrical response is unclear, thus it is necessary to clarify the lower limit of effective thickness for the tight sandstone gas pools. Based on the study of "the four property relationship", this article takes the Upper Paleozoic tight sandstone gas reservoir of some gas field in Ordos basin as example,and systematically describes the method of determining effective thickness lower limit of tight sandstone gas pools,and the test method,the experience statistics method,the mercury injection parameter method and the logging curves method are respectively discussed. Compared with the actual gas testing data, the effective thickness lower limit determined by these methods is reasonable and meets up with the actual geological characters,of which the operation is simple and applies well.%致密砂岩气藏作为非常规油气资源的主力,已经越来越受到重视.由于致密砂岩气藏不同于常规气藏,具有储层致密、物性差、电性响应不明显的特点,因此有必要针对致密砂岩气藏的有效厚度下限进行研究.以鄂尔多斯盆地某气田上古生界致密砂岩气层为例,在“四性”关系研究的基础上,较为系统地阐述了致密砂岩气藏有效厚度下限确定的方法,重点探讨了测试法、经验统计法、压汞参数法和测井曲线法.实际试气数据和横向对比验证表明,这些方法确定的有效厚度下限合理,符合研究区实际地质特点,操作简单,应用效果好.

  4. Tracing kinematic (mis)alignments in CALIFA merging galaxies: Stellar and ionized gas kinematic orientations at every merger stage

    CERN Document Server

    Barrera-Ballesteros, J K; Falcón-Barroso, J; van de Ven, G; Lyubenova, M; Wild, V; Méndez-Abreu, J; Sánchez, S F; Marquez, I; Masegosa, J; Monreal-Ibero, A; Ziegler, B; del Olmo, A; Verdes-Montenegro, L; García-Benito, R; Husemann, B; Mast, D; Kehrig, C; Iglesias-Paramo, J; Marino, R A; Aguerri, J A L; Walcher, C J; Vílchez, J M; Bomans, D J; Cortijo-Ferrero, C; Delgado, R M González; Bland-Hawthorn, J; McIntosh, D H; Bekeraite, Simona

    2015-01-01

    We present spatially resolved stellar and/or ionized gas kinematic properties for a sample of 103 interacting galaxies, tracing all merger stages: close companions, pairs with morphological signatures of interaction, and coalesced merger remnants. We compare our sample with 80 non-interacting galaxies. We measure for the stellar and the ionized gas components the major (projected) kinematic position angles (PA$_{\\mathrm{kin}}$, approaching and receding) directly from the velocity fields with no assumptions on the internal motions. This method allow us to derive the deviations of the kinematic PAs from a straight line ($\\delta$PA$_{\\mathrm{kin}}$). Around half of the interacting objects show morpho-kinematic PA misalignments that cannot be found in the control sample. Those misalignments are present mostly in galaxies with morphological signatures of interaction. Alignment between the kinematic sides for both samples is similar, with most of the galaxies displaying small misalignments. Radial deviations of the...

  5. The alignment and shape of dark matter, stellar, and hot gas distributions in the EAGLE and cosmo-OWLS simulations

    Science.gov (United States)

    Velliscig, Marco; Cacciato, Marcello; Schaye, Joop; Crain, Robert A.; Bower, Richard G.; van Daalen, Marcel P.; Dalla Vecchia, Claudio; Frenk, Carlos S.; Furlong, Michelle; McCarthy, I. G.; Schaller, Matthieu; Theuns, Tom

    2015-10-01

    We report the alignment and shape of dark matter, stellar, and hot gas distributions in the EAGLE (Evolution and Assembly of GaLaxies and their Environments) and cosmo-OWLS (OverWhelmingly Large Simulations) simulations. The combination of these state-of-the-art hydrodynamical cosmological simulations enables us to span four orders of magnitude in halo mass (11 ≤ log10(M200/[ h-1 M⊙]) ≤ 15), a wide radial range (-2.3 ≤ log10(r/[ h-1 Mpc]) ≤ 1.3) and redshifts 0 ≤ z ≤ 1. The shape parameters of the dark matter, stellar and hot gas distributions follow qualitatively similar trends: they become more aspherical (and triaxial) with increasing halo mass, radius, and redshift. We measure the misalignment of the baryonic components (hot gas and stars) of galaxies with their host halo as a function of halo mass, radius, redshift, and galaxy type (centrals versus satellites and early- versus late-type). Overall, galaxies align well with the local distribution of the total (mostly dark) matter. However, the stellar distributions on galactic scales exhibit a median misalignment of about 45-50 deg with respect to their host haloes. This misalignment is reduced to 25-30 deg in the most massive haloes (13 ≤ log10(M200/[ h-1 M⊙]) ≤ 15). Half of the disc galaxies in the EAGLE simulations have a misalignment angle with respect to their host haloes larger than 40 deg. We present fitting functions and tabulated values for the probability distribution of galaxy-halo misalignment to enable a straightforward inclusion of our results into models of galaxy formations based on purely collisionless N-body simulations.

  6. Imaging Molecular Structure through Femtosecond Photoelectron Diffraction on Aligned and Oriented Gas-Phase Molecules

    DEFF Research Database (Denmark)

    Boll, Rebecca; Rouzee, Arnaud; Adolph, Marcus;

    2014-01-01

    This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray Free-Electron Laser. We present results of two experiments aimed at measuring photoelectron angular...

  7. Tight Diabetes Control

    Science.gov (United States)

    ... Size: A A A Listen En Español Tight Diabetes Control Keeping your blood glucose levels as close ... and syringes, than before. What About Type 2 Diabetes? The DCCT studied only people with type 1 ...

  8. The Morphologies and Alignments of Gas, Mass, and the Central Galaxies of CLASH Clusters of Galaxies

    CERN Document Server

    Donahue, Megan; Rasia, Elena; Sayers, Jack; Zitrin, Adi; Meneghetti, Massimo; Voit, G Mark; Golwala, Sunil; Czakon, Nicole; Yepes, Gustavo; Baldi, Alessandro; Koekemoer, Anton; Postman, Marc

    2016-01-01

    Morphology is often used to infer the state of relaxation of galaxy clusters. The regularity, symmetry, and degree to which a cluster is centrally concentrated inform quantitative measures of cluster morphology. The Cluster Lensing and Supernova survey with Hubble Space Telescope (CLASH) used weak and strong lensing to measure the distribution of matter within a sample of 25 clusters, 20 of which were deemed to be relaxed based on their X-ray morphology and alignment of the X-ray emission with the BCG. Towards a quantitative characterization of this important sample of clusters, we present uniformly estimated X-ray morphological statistics for all 25 CLASH clusters. We compare X-ray morphologies of CLASH clusters with those identically measured for a large sample of simulated clusters from the MUSIC-2 simulations, selected by mass. We confirm a threshold in X-ray surface brightness concentration of C>0.4 for cool-core clusters, where C is the ratio of X-ray emission inside 100 kpc/h70 compared to inside 500 k...

  9. Briefly Discuss on Tightness Test and Maintenance of Gas Fire Extinguishing System’s Start Pipeline%浅谈气体灭火系统启动管道的气密性试验和维护保养

    Institute of Scientific and Technical Information of China (English)

    刘富标

    2014-01-01

    气体灭火系统用于重要设备房内,如设备房内发生火灾系统将自动喷气进行灭火。气体灭火系统的启动管道是喷气式,用于输送启动瓶的氮气打开选择阀和灭火剂存储钢瓶瓶头阀,而启动管道满足气密性要求是保证气体灭火剂正常喷发的先决条件,因而必须在施工验收期间进行启动管道气密性试验并在日常维护中重点关注其气密性是否满足要求。仅就气体灭火系统启动管道气密性试验的必要性、具体方法及其维护保养提出一些看法,供气体灭火系统相关单位进行施工验收和维护保养时参考。%Gas extinguishing systems is used in important equipment room,when the fire broke out it will release extinguishing agent to put out the fire. When releasing extinguishing agent, the start pipeline of gas fire extinguishing system is used to transfer the nitrogen of starting receiver to open selector valve and extinguishing agent storage steel cylinder’s bottle valve. The tightness of start pipeline is the precondition for gas releasing. So it’ s important to do tightness test when it’ s under construction and acceptance, it’ s also very important to pay close attention to the tightness of start pipeline in daily maintain. This article will discuss the importance of start pipeline’ s tightness test,and how to do tightness test and maintenance method,to provide a reference to those who need.

  10. Geological characteristics of the Triassic tight sandstone oil and gas reservoirs in Luoyang-Yichuan area%洛阳-伊川地区三叠系致密砂岩油气藏地质特征

    Institute of Scientific and Technical Information of China (English)

    杜建波; 田景春; 胡俊卿; 曹建康

    2013-01-01

    Research of the petroleum geological conditions indicates that Luoyang-Yichuan area is located in the same large depressed lacustrine basin with Ordos Basin in the Triassic.They have similar source-reservoir-caprock associations,thick and extensive source rocks,tight reservoir and active hydrocarbon shows in the Triassic.Therefore,the Luoyang-Yichuan area has the geological conditions for accumulation of tight sand oil/gas.In combination with the analysis of industrial gas flow from the Upper Triassic Chunshuyao Formation in Well Tun 1,we believe that the Triassic reservoirs of the Luoyang-Yichuan area are pre-existing tight sandstone oil/gas reservoirs with low permeability,abnormal pressure,inverted oil-gas contact with oil in the upper and gas in the lower.The Triassic tight sandstone reservoirs are the main targets of petroleum exploration in Luoyang-Yichuan area in the future.%通过对洛阳-伊川地区三叠系基本石油地质条件的分析,认为三叠纪洛阳-伊川地区与鄂尔多斯盆地处于同一大型坳陷型湖盆,生储盖架构相似,烃源岩发育、厚度大、横向展布稳定、储层致密,且三叠系油气显示丰富,具致密砂岩油气藏形成的地质条件.结合对屯l井上三叠统椿树腰组工业天然气流分析,进一步明确了洛阳-伊川地区三叠系油气藏为具有低孔渗性、地层压力异常、油气呈“上油下气”倒置关系等特征的先成型致密砂岩油气藏,从而指出三叠系为洛阳-伊川地区下一步油气勘探的主攻层系,致密砂岩油气藏是该区勘探的主要方向.

  11. 苏里格大型致密砂岩气田开发井型井网技术%Well type and pattern optimization technology for large scale tight sand gas,Sulige gas field

    Institute of Scientific and Technical Information of China (English)

    何东博; 贾爱林; 冀光; 位云生; 唐海发

    2013-01-01

    Sulige gas field is a typical tight sand gas field in China. Well type and pattern optimization is the key technology to improve single well estimated reserves and recovery factor and to achieve effective field development. In view of the large area, low abundance and high heterogeneity of Sulige gas field, a series of techniques have been developed including hierarchical description for the reservoir architecture of large composite sand bodies and well spacing optimization, well pattern optimization, design and optimization for horizontal trajectory and deliverability evaluation for different types of gas wells. These technologies provide most important technical supports for the increases of class ⅠandⅡ wells proportion to 75%-80% with recovery factor enhanced by more than 35% and for the industrial application of horizontal drilling. To further improve individual well production and recovery factor, attempts and pilot tests in various well types including side tracking of deficient wells, multilateral horizontal wells, and directional wells, and horizontal well pattern and combined well pattern of various well types should be carried out throughout the development.%苏里格气田是中国致密砂岩气田的典型代表,井型井网技术是其提高单井控制储量和采收率、实现气田规模有效开发的关键技术.针对苏里格气田大面积、低丰度、强非均质性的特征,形成了大型复合砂体分级构型描述与优化布井技术、井型井网优化技术、水平井优化设计技术和不同类型井产能评价技术,为苏里格气田产能建设Ⅰ +Ⅱ类井比例达到75%~80%、预期采收率提高到35%以上以及水平井的规模化应用发挥了重要的技术支撑作用.为进一步提高苏里格气田单井产量和采收率,应继续开展低效井侧钻、多分支水平井、多井底定向井等不同井型,以及水平井井网、多井型组合井网的探索和开发试验.

  12. Palladium-decorated hydrogen-gas sensors using periodically aligned graphene nanoribbons.

    Science.gov (United States)

    Pak, Yusin; Kim, Sang-Mook; Jeong, Huisu; Kang, Chang Goo; Park, Jung Su; Song, Hui; Lee, Ryeri; Myoung, NoSoung; Lee, Byoung Hun; Seo, Sunae; Kim, Jin Tae; Jung, Gun-Young

    2014-08-13

    Polymer residue-free graphene nanoribbons (GNRs) of 200 nm width at 1 μm pitch were periodically generated in an area of 1 cm(2) via laser interference lithography using a chromium interlayer prior to photoresist coating. High-quality GNRs were evidenced by atomic force microscopy, micro-Raman spectroscopy, and X-ray photoelectron spectroscopy measurements. Palladium nanoparticles were then deposited on the GNRs as catalysts for sensing hydrogen gases, and the GNR array was utilized as an electrically conductive path with less electrical noise. The palladium-decorated GNR array exhibited a rectangular sensing curve with unprecedented rapid response and recovery properties: 90% response within 60 s at 1000 ppm and 80% recovery within 90 s in nitrogen ambient. In addition, reliable and repeatable sensing behaviors were revealed when the array was exposed to various gas concentrations even at 30 ppm. PMID:25050896

  13. Tight products and Expansion

    CERN Document Server

    Daniely, Amit

    2010-01-01

    In this paper we study a new product of graphs called {\\em tight product}. A graph $H$ is said to be a tight product of two (undirected multi) graphs $G_1$ and $G_2$, if $V(H)=V(G_1)\\times V(G_2)$ and both projection maps $V(H)\\to V(G_1)$ and $V(H)\\to V(G_2)$ are covering maps. It is not a priori clear when two given graphs have a tight product (in fact, it is $NP$-hard to decide). We investigate the conditions under which this is possible. This perspective yields a new characterization of class-1 $(2k+1)$-regular graphs. We also obtain a new model of random $d$-regular graphs whose second eigenvalue is almost surely at most $O(d^{3/4})$. This construction resembles random graph lifts, but requires fewer random bits.

  14. Change of Magnetic Field$-$Gas Alignment at Gravity-Driven Alfv\\'enic Transition in Molecular Clouds: Implications for Dust Polarization Observations

    CERN Document Server

    Chen, Che-Yu; Li, Zhi-Yun

    2016-01-01

    Diffuse striations in molecular clouds are preferentially aligned with local magnetic fields whereas dense filaments tend to be perpendicular to them. When and why this transition occurs remain uncertain. To explore the physics behind this transition, we compute the histogram of relative orientation (HRO) between the density gradient and the magnetic field in 3D MHD simulations of prestellar core formation in shock-compressed regions within GMCs. We find that, in the magnetically-dominated (sub-Alfv\\'enic) post-shock region, the gas structure is preferentially aligned with the local magnetic field. For overdense sub-regions with super-Alfv\\'enic gas, their elongation becomes preferentially perpendicular to the local magnetic field instead. The transition occurs when self-gravitating gas gains enough kinetic energy from the gravitational acceleration to overcome the magnetic support against the cross-field contraction, which results in a power-law increase of the field strength with density. Similar results ca...

  15. Tight bifunctional hierarchical catalyst.

    Science.gov (United States)

    Højholt, Karen T; Vennestrøm, Peter N R; Tiruvalam, Ramchandra; Beato, Pablo

    2011-12-28

    A new concept to prepare tight bifunctional catalysts has been developed, by anchoring CoMo(6) clusters on hierarchical ZSM-5 zeolites for simultaneous use in HDS and hydrocracking catalysis. The prepared material displays a significant improved activity in HDS catalysis compared to the impregnated counterpart. PMID:22048337

  16. Leak-tightness technology

    International Nuclear Information System (INIS)

    In this chapter on the leak-tightness of welded joints a study is made of welding and bonding technology (metals, glass-metals, ceramic-metals), the welding of flanges and collars, the welding of end pieces, the welding of an electric crossover and a bellows

  17. Influential factors of Horizontal Well Volume Fracturing Productivity in He 8 Tight Gas Reservoir%盒8致密气储层水平井体积压裂增产影响因素

    Institute of Scientific and Technical Information of China (English)

    苏玉亮; 袁彬; 李硕轩; 古永红; 李红英; 苏国辉

    2013-01-01

    体积压裂技术形成以主裂缝为主干的纵横“网状缝”,适合低孔、低渗油气藏的储层改造.基于盒8致密气储层特征,建立应力敏感和井筒摩阻条件下的水平井体积压裂模型,数值模拟不同储层特点,分析地质条件及缝网特征对体积压裂改造效果影响.结果表明,体积压裂水平井可明显改善致密气藏渗流环境,提高单井产能;压力系数、储层渗透率主要影响体积压裂改造效果;储层有效改造体积越大,压后增产越明显;缝网宽长、裂缝导流、裂缝排布等对体积压裂改造增产效果影响依次增大.研究结果为致密气藏体积压裂优化设计和效果评价提供一定的理论依据.%Volume fracturing technology could result in a seam-cross network,which is conductive to the development of tight gas reservoir.The horizontal well volume fracturing model is established by considering stress sensitiveness and wellbore friction based on He 8 tight gas reservoirs characteristics.The effect of geologic factors and network features on the efficiency of horizontal well volume fracturing is analyzed by the numerical simulation of different geological conditions.The result shows that network fracturing could change the seepage environment,increase reservoir production extent,improve well performance greatly; the processing factors have different influential extents.The pressure coefficient and permeability mainly affect the volume fracturing efficiency,with the increase of effective remolded volume,the productivity improvement could be more distinct,network width and length,fracture conductivity,and network distribution successively affect volume fracturing remolded efficiency.The research result provides the theoretical basis for both optimal design and effectiveness evaluation of volume fracturing in the tight gas reservoir.

  18. Continuous Shearlet Tight Frames

    KAUST Repository

    Grohs, Philipp

    2010-10-22

    Based on the shearlet transform we present a general construction of continuous tight frames for L2(ℝ2) from any sufficiently smooth function with anisotropic moments. This includes for example compactly supported systems, piecewise polynomial systems, or both. From our earlier results in Grohs (Technical report, KAUST, 2009) it follows that these systems enjoy the same desirable approximation properties for directional data as the previous bandlimited and very specific constructions due to Kutyniok and Labate (Trans. Am. Math. Soc. 361:2719-2754, 2009). We also show that the representation formulas we derive are in a sense optimal for the shearlet transform. © 2010 Springer Science+Business Media, LLC.

  19. 生物再生生命保障地基实验系统气密性评价%Evaluation on Gas Tightness of Ground-based Experimental Bioregenerative Life Support System

    Institute of Scientific and Technical Information of China (English)

    胡大伟; 付玉明; 杜小杰; 张金晖; 刘红

    2016-01-01

    The gas tightness or leakage rate is an important technical parameter for the ground-based experimental Bioregenerative Life Support System (BLSS), because it directly determines the closure degree of the system and the accuracy of data from human-rated experiments .In this research , the mechanism of gas ( O2 and CO2 ) transient response to leakage rates in Lunar Palace 1, a prototype of BLSS in China , was investigated with mathematical model developed by gas equation , experimen-tal data and system dynamics , simulation model established by S-function on the platform of Matlab/Simulink , and theory of stochastic process .The gas tightness tests showed that the actual leakage rate of the Lunar Palace 1 cabin was 0.043%· d-1 which was almost a completely closed level via simulation and calculation .The gas steady-state response characteristics were also analyzed elabo-rately by stochastic process method to verify that the gas concentrations were robustly stable during the 105-day human-rated experiment in the Lunar Palace 1, and the actual leakage rate of cabin did not adversely affect experimental results , namely the gas tightness ensured the accuracy and reliabil-ity of data obtained from the human-rated experiment .This research may provide a theoretical and methodological basis for the design and building of BLSS in China .%针对直接影响生物再生生命保障系统地基实验系统有人密闭系统实验数据准确性的气密性或泄露率问题,以月宫一号大型地基实验系统为例,采用经典气体方程和系统动力学原理建立了影响其舱内气体动态的主要速率方程,并把泄露率作为其中的可调节参数,运用Mat-lab/Simulink中的S函数建立气体浓度对泄露率变化的瞬态响应特征模型.通过数值仿真实验研究,分析了在假设的不同泄露率下,月宫一号系统内O2和CO2气体浓度的动态变化规律.经气密性检验实验测定,月宫一号系统的舱体实际泄漏率为0

  20. 从致密油气到页岩油气——中国非常规油气发展之路探析%From Tight Oil & Gas to Shale Oil & Gas —— Approach for the Development of Unconventional Oil & Gas in China

    Institute of Scientific and Technical Information of China (English)

    张抗

    2012-01-01

    与国外不同,中国多把致密油气与常规资源放在一起统计。致密油气已在美、中油气产储量,特别是待发现资源量构成中占重要地位。由于致密油气开发的成功,中国在水平井和压裂两大技术系列上已总体达到国际先进水平,这为煤层气、页岩油气的开发提供了条件。美国页岩气大发展造成气价下跌,这促进了页岩油的发展并使其石油产量由长期下降转为较快速上升。中国煤层气发展的教训显示出管理体制不顺和市场环境缺失是阻碍非常规油气发展的首要因素。尊重不同类型资源共生伴生的规律,在油气,特别是非常规油气发展中应倡导综合勘探开发和利用。对在中国研究程度尚很低的页岩油气开发不可急于求成,只能在尊重勘探程序的基础上加快。%Unlike other countries, China often count tight oil & gas as conventional resources statistically. In fact, the tight oil & gas has accounted for a considerable percentage in the oil & gas production and reserves of the US and China, in particular the mix of resources to be discovered. With success in the development of tight oil & gas, on the whole, China has reached an advanced international level in the two technology series: horizontal well and fracturing, thereby creating conditions for the development of coal seam gas and shale oil & gas. The great advancement of shale gas in the US brought about drop of gas prices and facilitated the development of shale oil in turn; consequently, its oil production changes from long term falling to rising. The lessons from the development of coal seam gas in China indicate that inefficient management system and lacking of market environment are two primary factors impeding the development of unconventional oil & gas resources, we should advocate comprehensive exploration, development In view of the symbiotic and associated features of various and utilization in the

  1. Comparative evaluation of eight software programs for alignment of gas chromatography-mass spectrometry chromatograms in metabolomics experiments.

    Science.gov (United States)

    Niu, Weihuan; Knight, Elisa; Xia, Qingyou; McGarvey, Brian D

    2014-12-29

    Since retention times of compounds in GC-MS chromatograms always vary slightly from chromatogram to chromatogram, it is necessary to align chromatograms before comparing them in metabolomics experiments. Several software programs have been developed to automate this process. Here we report a comparative evaluation of the performance of eight programs using prepared samples of mixtures of chemicals, and an extract of tomato vines spiked with three concentrations of a mixture of alkanes. The programs included in the comparison were SpectConnect, MetaboliteDetector 2.01a, MetAlign 041012, MZmine 2.0, TagFinder 04, XCMS Online 1.21.01, MeltDB and GAVIN. Samples were analyzed by GC-MS, chromatograms were aligned using the selected programs, and the resulting data matrices were preprocessed and submitted to principal components analysis. In the first trial, SpectConnect, MetAlign and MetaboliteDetector correctly identified ≥90% of the true positives. In the second trial, MetAlign and MetaboliteDetector correctly identified 87% and 81% of the true positives, respectively. In addition, in both trials >90% of the peaks identified by MetAlign and MetaboliteDetector were true positives. PMID:25435458

  2. X-ray Diffraction from Isolated and Strongly Aligned Gas-Phase Molecules with a Free-Electron Laser

    DEFF Research Database (Denmark)

    Küpper, Jochen; Stern, Stephan; Holmegaard, Lotte;

    2014-01-01

    We report experimental results on x-ray diffraction of quantum-state-selected and strongly aligned ensembles of the prototypical asymmetric rotor molecule 2,5-diiodobenzonitrile using the Linac Coherent Light Source. The experiments demonstrate first steps toward a new approach to diffractive ima...

  3. Opportunities and risks of hydraulic fraction treatment of tight gas-carrying rocks in redbeds; Chancen und Risiken hydraulischer Fracbehandlungen von dichten Erdgasspeichergesteinen im Rotliegenden

    Energy Technology Data Exchange (ETDEWEB)

    Buhrow, C. [BEB Erdgas und Erdoel GmbH, Hannover (Germany)

    1998-12-31

    In the last 20 years more and more hydraulic fraction treatments have been carried out in natural gas-carrying strata of the redbed. By pumping high-viscosity liquids into the rocks one attempts to control the fraction. Towards the end of the treatment the fraction is filled with a proppant in order to create a flow path with high permeability to the borehole after the pressure of the liquid drops. The trend moves from large-volume single fractures - more than 2000 cubic m of liquid as several tons of proppant were used in some cases -. to smaller fraction treatments consisting of a minimum of two fractures: the first one, which usually employs small amounts of liquid and proppant, serves to gain information on the deposit and its suitability for fraction treatment. The one or several fractures that follow serve to increase production or enlarge the drainage area. Ground pressure measurements can provide important information about the development of the fracture before, during and after fracturing. (orig.) [Deutsch] Seit ca. 20 Jahren werden vermehrt hydraulische Fracbehandlungen in den Erdgasspeichergesteinen des Rotliegenden durchgefuehrt. Durch Verpumpen von Fluessigkeiten hoher Viskositaet soll kontrolliert ein Riss `Frac` genannt, im Gebirge geschaffen werden. Dieser wird gegen Ende der Behandlung mit Stuetzmittel angefuellt, um nach Abfall des Fluessigkeitsdrucks einen bleibenden Fliessweg hoher Permeabilitaet zum Bohrloch zu schaffen. Dabei hat es eine Entwicklung von grossvolumigen Einzelfracs - in Einzelfaellen wurden mehr als 2.000 m{sup 3} Fluessigkeit und mehrere hundert Tonnen Stuetzmittel verpumpt - hin zu kleineren Fracbehandlungen aus zumindest zwei Fracs gegeben: Ziel des ersten, zumeist nur geringe Fluessigkeitsvolumina und Stuetzmittelmengen enthaltenen Fracs ist es, Informationen ueber die Lagerstaette und deren Fracbehandelbarkeit zu erlangen. Der oder die nachfolgenden Fracs dienen dann dem eigentlichen Ziel, der Produktionssteigerung und der

  4. 基于LabVIEW的深海气密采水器测控系统%Measurement and control system for gas-tight deep-sea water sampler based on LabVIEW

    Institute of Scientific and Technical Information of China (English)

    黄豪彩; 杨灿军; 陈道华; 牛文达; 陈鹰

    2011-01-01

    The measurement and control system of exiting conventional CTD sampler suffers from low automation level and complicated operation. In order to solve this problem, a measurement and control system based on LabVIEW for gas-tight deep-sea water sampler was developed. The measurement principle of temperature, salinity and depth was studied. The hardware and software of the system were designed. In the year of 2009 , the measurement and control system worked well during the HY4-2009-2 cruise of " Hai Yang Si Hao" research vessel in South China Sea.Quick and precise control of the gas-tight deep-sea water sampler was achieved. The acquisition , processing, display and storage of temperature, salinity and depth parameters were implemented conveniently in real-time. The results of sea trials show that the system features high measurement and control precision, good stability and reliability, high automation level and easy operation. The system is appreciated by researchers. Furthermore, the proposed method can also be used widely in the measurement and control systems of various oceanic instruments and equipment.%现有常规CTD采水器测控系统自动化程度低、操作复杂.为此,基于LabVIEW软件开发了深海气密采水器测控系统,研究温度、盐度和深度测量原理,进行测控系统的硬、软件设计.2009年该测控系统在我国"海洋四号"科考船"HY4-2009-2"航次中成功应用,在中国海南试验中实现对深海气密采水器的快速、精确控制,并实时进行温度、盐度和深度等参数的采集、处理、显示和存储.海上试验表明,该测控系统具有测量与控制精度高、运行稳定可靠、自动化程度高、操作简便等特点,获得科研人员较好评价.该方法可推广到其他海洋仪器、设备的测控系统中应用.

  5. Change of Magnetic Field-gas Alignment at the Gravity-driven Alfvénic Transition in Molecular Clouds: Implications for Dust Polarization Observations

    Science.gov (United States)

    Chen, Che-Yu; King, Patrick K.; Li, Zhi-Yun

    2016-10-01

    Diffuse striations in molecular clouds are preferentially aligned with local magnetic fields, whereas dense filaments tend to be perpendicular to them. When and why this transition occurs remain uncertain. To explore the physics behind this transition, we compute the histogram of relative orientation (HRO) between the density gradient and the magnetic field in three-dimensional magnetohydrodynamic (MHD) simulations of prestellar core formation in shock-compressed regions within giant molecular clouds. We find that, in the magnetically dominated (sub-Alfvénic) post-shock region, the gas structure is preferentially aligned with the local magnetic field. For overdense sub-regions with super-Alfvénic gas, their elongation becomes preferentially perpendicular to the local magnetic field. The transition occurs when self-gravitating gas gains enough kinetic energy from the gravitational acceleration to overcome the magnetic support against the cross-field contraction, which results in a power-law increase of the field strength with density. Similar results can be drawn from HROs in projected two-dimensional maps with integrated column densities and synthetic polarized dust emission. We quantitatively analyze our simulated polarization properties, and interpret the reduced polarization fraction at high column densities as the result of increased distortion of magnetic field directions in trans- or super-Alfvénic gas. Furthermore, we introduce measures of the inclination and tangledness of the magnetic field along the line of sight as the controlling factors of the polarization fraction. Observations of the polarization fraction and angle dispersion can therefore be utilized in studying local magnetic field morphology in star-forming regions.

  6. LNG船舶燃气双壁管的制作、焊接、密性试验研究%Research on Manufacture & Welding & Gas Tightness Test of LNG Carrier Double Wall Piping

    Institute of Scientific and Technical Information of China (English)

    高振宇; 于彩霞; 佟国志

    2014-01-01

    Based on the gas double-walled tube adopted by 28000m3 LNG ship project, double-wall pipe diameter calculation and model of the arrangement are considered in the design stage. As well as combining with the manufacture, welding, tightness research on the ship, the double wall piping which meets the inspection requirements of the owner and classification society is produced. This research can provide a practical guidance for the building of LNG ship using the double-wall piping in the future.%结合28000m3LNG船舶项目所采用的燃气双壁管,在设计阶段考虑双壁管口径的计算及模型的布置,结合现场阶段制作、焊接、密性研究,最终提供满足船东、船级社检验要求的产品,同时为今后建造LNG船舶采用的双壁管提供了指导意义。

  7. Naturally fractured tight gas reservoirs detection optimization

    Energy Technology Data Exchange (ETDEWEB)

    Hoekstra, P. [Coleman Research Corp., Orlando, FL (United States)

    1995-04-01

    This contract is a joint project between METC and Louisiana Land and Exploration, planned to extend for 3 years. Substantial help and key information has been provided at the field by the owner/operator. All their well logs, cores, production data, geologic data, and geophysical data are available for study in this project. Their commitment in this technology development is demonstrated by their proposed contribution in the form of cost sharing: (1) obtaining the P-Wave (compressional wave) 3-D survey, (2) furnishing a borehole in which to acquire the 9-C vertical seismic profile (VSP), and (3) drilling and completing a test well for verification of the seismic anomaly. Also of significance is the direct involvement and participation of their professional staff. This staff has been responsible for generating and maintaining the database at the field and will form part of the team which evaluates the seismic data`s findings.

  8. Naturally fractured tight gas reservoir detection optimization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-30

    The focus of this report was on preparing data and modules for Piceance Basin-wide fracture prediction. A review of the geological data input and automated history reconstruction approach was made. Fluid pressure data analysis and preliminary basin simulations were carried out. These activities are summarized briefly below and reviewed in more detail in Appendices A-E. Appendix D is a review of the fluid pressure data and its implications for compartmentation. Preliminary fracture prediction computations on generic basins are presented in Appendix E; these were carried out as part of our code testing activities. The results of these two Appendices are the beginning of what will be the basis of the model testing; fluid pressures are directly comparable with the model predictions and are a key element of fracture nucleation and presentation. We summarize the tectonic and sedimentary history of the Piceance Basin based on our automated history reconstruction and published interpretations. The narrative and figures provide the basic material we have quantified for our CIRF.B basin simulator input. This data supplements our existing well data interpretation approach. It provides an independent check of the automated sedimentary/subsidence history reconstruction module. Fluid pressure data was gathered and analyzed. This data serves two functions. Fluid pressure distribution across the basin provides a quantitative test as it is a direct prediction of CIRF.B. Furthermore, fluid pressure modifies effective stress. It thereby enters fracture nucleation criteria and fracture extension rate and aperture laws. The pressure data is presented in Appendix Din terms of overpressure maps and isosurfaces.

  9. Naturally fractured tight gas reservoir detection optimization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-30

    The work plan for the quarter of October 1, 1997--December 31, 1997 consisted of two tasks: (1) Present results of Rulison field test at various conferences, seminars, and to Barrett Resources and Snyder Oil Co. and (2) Continue work into developing a predictive quantitative method for locating fault-related natural fractures. The first task was completed during this reporting period. The second task continues the beginning of quantitative fracture mechanics analysis of the geologic processes that are involved for the development of fault-related natural fractures. The goal of this work is to develop a predictive capability of locating natural fractures prior to drilling.

  10. Beyond Alignment

    DEFF Research Database (Denmark)

    Beyond Alignment: Applying Systems Thinking to Architecting Enterprises is a comprehensive reader about how enterprises can apply systems thinking in their enterprise architecture practice, for business transformation and for strategic execution. The book's contributors find that systems thinking...

  11. Tight Bernoulli tail probability bounds

    OpenAIRE

    Dzindzalieta, Dainius

    2014-01-01

    The purpose of the dissertation is to prove universal tight bounds for deviation from the mean probability inequalities for functions of random variables. Universal bounds shows that they are uniform with respect to some class of distributions and quantity of variables and other parameters. The bounds are called tight, if we can construct a sequence of random variables, such that the upper bounds are achieved. Such inequalities are useful for example in insurance mathematics, for constructing...

  12. Tight p-fusion frames

    OpenAIRE

    Bachoc, Christine; Ehler, Martin

    2012-01-01

    Fusion frames enable signal decompositions into weighted linear subspace components. For positive integers p, we introduce p-fusion frames, a sharpening of the notion of fusion frames. Tight p-fusion frames are closely related to the classical notions of designs and cubature formulas in Grassmann spaces and are analyzed with methods from harmonic analysis in the Grassmannians. We define the p-fusion frame potential, derive bounds for its value, and discuss the connections to tight p-fusion fr...

  13. Orientation and Alignment Echoes

    CERN Document Server

    Karras, G; Billard, F; Lavorel, B; Hartmann, J -M; Faucher, O; Gershnabel, E; Prior, Y; Averbukh, I Sh

    2015-01-01

    We present what is probably the simplest classical system featuring the echo phenomenon - a collection of randomly oriented free rotors with dispersed rotational velocities. Following excitation by a pair of time-delayed impulsive kicks, the mean orientation/alignment of the ensemble exhibits multiple echoes and fractional echoes. We elucidate the mechanism of the echo formation by kick-induced filamentation of phase space, and provide the first experimental demonstration of classical alignment echoes in a thermal gas of CO_2 molecules excited by a pair of femtosecond laser pulses.

  14. CO(1-0) survey of high-z radio galaxies: alignment of molecular halo gas with distant radio sources

    CERN Document Server

    Emonts, B H C; Feain, I; Mao, M Y; Ekers, R D; Miley, G; Seymour, N; Roettgering, H J A; Villar-Martin, M; Sadler, E M; Carilli, C L; Mahony, E K; de Breuck, C; Stroe, A; Pentericci, L; van Moorsel, G A; Drouart, G; Ivison, R J; Greve, T R; Humphrey, A; Wylezalek, D; Tadhunter, C N

    2013-01-01

    We present a CO(1-0) survey for cold molecular gas in a representative sample of 13 high-z radio galaxies (HzRGs) at 1.4gas mass derived for these two systems is M$_{\\rm H2} \\sim 6 \\times 10^{10}\\, {\\rm M}_{\\odot}$ (M$_{\\rm H2}$/$L'_{\\rm CO}$=0.8). For the remaining three CO-detected sources, the CO(1-0) emission is located in the halo (~50-kpc) environment. These three HzRGs are among the fainter far-IR emitters in our sample, suggesting that similar reservoirs of cold molecular halo gas may have been missed in earlier studies d...

  15. Microfine grouting in tight fractures

    International Nuclear Information System (INIS)

    Microfine cements were used to grout tight fractures in basalt at McNary Dam in Umatilla, Oregon. Six boreholes were grouted with different microfine mixes. Hydraulic conductivity testing before and after the grouting provided a quantitative estimate of average fracture apertures and the effect of grouting on rock mass permeability. A downhole video camera survey was conducted in each hole to determine which fractures and joint sets allowed grout penetration. Pressure and the flow rate for grout were monitored during the testing. Total grout takes were calculated for each borehole stage grouted. Grouting pressures varied from less than a quarter to more than five times the estimated overburden pressure. The results of this testing indicate that tight fractures can be grouted with microfine cements. In addition, for tight fracture the relationship of injection pressures to grout take is significantly more non-linear than conventional grouting experience has suggested

  16. Observation of an Aligned Gas - Solid "Eutectic" during Controlled Directional Solidification Aboard the International Space Station - Comparison with Ground-based Studies

    Science.gov (United States)

    Grugel, R. N.; Anilkumar, A.

    2005-01-01

    Direct observation of the controlled melting and solidification of succinonitrile was conducted in the glovebox facility of the International Space Station (ISS). The experimental samples were prepared on ground by filling glass tubes, 1 cm ID and approximately 30 cm in length, with pure succinonitrile (SCN) in an atmosphere of nitrogen at 450 millibar pressure for eventual processing in the Pore Formation and Mobility Investigation (PFMI) apparatus in the glovebox facility (GBX) on board the ISS. Real time visualization during controlled directional melt back of the sample showed nitrogen bubbles emerging from the interface and moving through the liquid up the imposed temperature gradient. Over a period of time these bubbles disappear by dissolving into the melt. Translation is stopped after melting back of about 9 cm of the sample, with an equilibrium solid-liquid interface established. During controlled re-solidification, aligned tubes of gas were seen growing perpendicular to the planar solid/liquid interface, inferring that the nitrogen previously dissolved into the liquid SCN was now coming out at the solid/liquid interface and forming the little studied liquid = solid + gas eutectic-type reaction. The observed structure is evaluated in terms of spacing dimensions, interface undercooling, and mechanisms for spacing adjustments. Finally, the significance of processing in a microgravity environment is ascertained in view of ground-based results.

  17. Alignment fixture

    Science.gov (United States)

    Bell, Grover C.; Gibson, O. Theodore

    1980-01-01

    A part alignment fixture is provided which may be used for precise variable lateral and tilt alignment relative to the fixture base of various shaped parts. The fixture may be used as a part holder for machining or inspection of parts or alignment of parts during assembly and the like. The fixture includes a precisely machined diameter disc-shaped hub adapted to receive the part to be aligned. The hub is nested in a guide plate which is adapted to carry two oppositely disposed pairs of positioning wedges so that the wedges may be reciprocatively positioned by means of respective micrometer screws. The sloping faces of the wedges contact the hub at respective quadrants of the hub periphery. The lateral position of the hub relative to the guide plate is adjusted by positioning the wedges with the associated micrometer screws. The tilt of the part is adjusted relative to a base plate, to which the guide plate is pivotally connected by means of a holding plate. Two pairs of oppositely disposed wedges are mounted for reciprocative lateral positioning by means of separate micrometer screws between flanges of the guide plate and the base plate. Once the wedges are positioned to achieve the proper tilt of the part or hub on which the part is mounted relative to the base plate, the fixture may be bolted to a machining, inspection, or assembly device.

  18. metAlignID: A high-throughout sofware tool set for automated detection of trace level contaminants in comprehensive LECO two-dimensional gas chromatography time-of-flight mass spectrometry data

    NARCIS (Netherlands)

    Lommen, A.; Kamp, van der H.J.; Kools, H.J.; Lee, van der M.K.; Weg, van der G.

    2012-01-01

    A new alternative data processing tool set, metAlignID, is developed for automated pre-processing and library-based identification and concentration estimation of target compounds after analysis by comprehensive two-dimensional gas chromatography with mass spectrometric detection. The tool set has b

  19. Fluid mechanics and rock fracture kinetics of fracture mesh system in tight sand gas reservoirs%致密砂岩气藏缝网系统渗流力学和岩石断裂动力学

    Institute of Scientific and Technical Information of China (English)

    赵海峰; 蒋迪; 石俊

    2016-01-01

    Based on fluid mechanics equations and the Galerkin method,a finite element model has been established to simulate fracture mesh seepage field of horizontal wells volume fracturing,and the relationship between fracture mesh conductivity and production has been studied under different fracture mesh scale.Unlike shale gas,fracture mesh scale is not the bigger the better for tight sand stone gas.It should be maintained in a small-to-medium scale (0.1≤FCI≤0.25) and a high conductivity main fracture is also required.From production-SRV curve,it is found that there exists a critical SRV value (optimal value),and the production increase is significantly smaller when SRV is beyond the critical value.In practice,together with FCI,the critical SRV value can be used to determine cluster spacing and number of clusters in horizontal well fracturing.This paper has studied the process conditions to form small-to-medium scale fracture mesh.An analytic relationship among fracturing fluid pump rate,viscosity,rock dynamic fracture toughness,elastic modulus,Poisson' s ratio,stress,natural fracture parameters and fracture net pressure is given by rock fracture kinetics,and then the optimized pump rate to form small-to-medium scale fracture mesh is determined by dynamic extension conditions on the fracture mesh edge.%基于渗流力学方程和伽辽金法建立水平井体积压裂缝网渗流场的有限元模型,研究了不同缝网形式与规模下产能随缝网导流能力的变化关系,研究发现致密砂岩与页岩不同,压裂的缝网规模并非越大越好,而应该维持在中小规模(0.1≤FCI≤0.25),且需要高导流能力的支撑主缝.在确定了裂缝形态的基础上,计算得到产能与SRV曲线,研究发现存在SRV临界值(优化值),若SRV超出临界值,产能增幅明显变小.在压裂实践中可由SRV临界值和FCI值,确定水平井分段压裂簇间距和簇数之间的关系.研究了形成中小规模缝网对应的施工条件,首先

  20. 致密砂岩气资源潜力关键参数确定方法--以吐哈盆地为例%Key parameter selection for tight gas resource potential:a case from Turfan-Hami Basin

    Institute of Scientific and Technical Information of China (English)

    王伟明; 赵旭; 孙计文; 段胜强; 王洋; 王贵磊; 闫旭; 田伟超

    2014-01-01

    致密砂岩气资源评价方法的选取与参数的确定对客观认识致密气的资源潜力至关重要。通过分析各种资源评价方法的优缺点,选取容积法,结合致密储层特征确定了致密界线和含气饱和度两个关键参数。结果表明,容积法是评价致密砂岩气资源潜力可信度较高的方法,但参数的准确求取需结合致密储层的特征;致密砂岩储层具有喉道细小、亲水性强和束缚水含量高等特点,而且渗流能力由喉道大小控制,亲水性受具体粘土矿物成分与含量控制,但不受粘土总量控制;伊利石含量越高,岩石的润湿角越小,亲水性就越强,而绿泥石刚好相反;天然气的浮力与毛管力之间的平衡关系可确定致密储层物性界线,该界线受地层倾角影响明显,从盆地中心到边缘临界致密界线逐渐变小;伊利石表面强吸附水形成的双电层具有较强的导电能力,使传统的阿尔奇公式不适合致密砂岩含气饱和度的解释。而印尼公式充分考虑了泥质含量的影响,更适合于致密储层含气饱和度的解释。%Selection of methods and relevant parameters is crucial for estimation of tight gas resources .The volumetric method was selected in this paper based on analysis of the advantages and disadvantages of different evaluation methods and relevant two key parameters were defined ,namely tightness limit and gas saturation .The results show that volumetric method is the most reliable method to evaluate tight gas resource potential .However,the accurate determination of rele-vant parameters should be based on the features of tight sandstone reservoir .Tight sandstone reservoirs are generally cha-racterized by small throat ,strong hydrophilicity and high bound water saturation .The size of throat controls the permeabi-lity.Hydrophilicity is controlled by clay mineral components and their contents rather than the total amount of clay mine

  1. Improving the quality of biomarker candidates in untargeted metabolomics via peak table-based alignment of comprehensive two-dimensional gas chromatography-mass spectrometry data.

    Science.gov (United States)

    Bean, Heather D; Hill, Jane E; Dimandja, Jean-Marie D

    2015-05-15

    The potential of high-resolution analytical technologies like GC×GC/TOF MS in untargeted metabolomics and biomarker discovery has been limited by the development of fully automated software that can efficiently align and extract information from multiple chromatographic data sets. In this work we report the first investigation on a peak-by-peak basis of the chromatographic factors that impact GC×GC data alignment. A representative set of 16 compounds of different chromatographic characteristics were followed through the alignment of 63 GC×GC chromatograms. We found that varying the mass spectral match parameter had a significant influence on the alignment for poorly-resolved peaks, especially those at the extremes of the detector linear range, and no influence on well-chromatographed peaks. Therefore, optimized chromatography is required for proper GC×GC data alignment. Based on these observations, a workflow is presented for the conservative selection of biomarker candidates from untargeted metabolomics analyses. PMID:25857541

  2. MAMA: An Algebraic Map for the Secular Dynamics of Planetesimals in Tight Binary Systems

    CERN Document Server

    Leiva, A M; Beaugé, C

    2013-01-01

    We present an algebraic map (MAMA) for the dynamical and collisional evolution of a planetesimal swarm orbiting the main star of a tight binary system (TBS). The orbital evolution of each planetesimal is dictated by the secular perturbations of the secondary star and gas drag due to interactions with a protoplanetary disk. The gas disk is assumed eccentric with a constant precession rate. Gravitational interactions between the planetesimals are ignored. All bodies are assumed coplanar. A comparison with full N-body simulations shows that the map is of the order of 100 times faster, while preserving all the main characteristics of the full system. In a second part of the work, we apply MAMA to the \\gamma-Cephei, searching for friendly scenarios that may explain the formation of the giant planet detected in this system. For low-mass protoplanetary disks, we find that a low-eccentricity static disk aligned with the binary yields impact velocities between planetesimals below the disruption threshold. All other sc...

  3. MAMA: an algebraic map for the secular dynamics of planetesimals in tight binary systems

    Science.gov (United States)

    Leiva, A. M.; Correa-Otto, J. A.; Beaugé, C.

    2013-12-01

    We present an algebraic map (MAMA) for the dynamical and collisional evolution of a planetesimal swarm orbiting the main star of a tight binary system. The orbital evolution of each planetesimal is dictated by the secular perturbations of the secondary star and gas drag due to interactions with a protoplanetary disc. The gas disc is assumed eccentric with a constant precession rate. Gravitational interactions between the planetesimals are ignored. All bodies are assumed coplanar. A comparison with full N-body simulations shows that the map is of the order of 102 times faster, while preserving all the main characteristics of the full system. In a second part of the work, we apply multiparticle algebraic map for accretion (MAMA) to the γ-Cephei, searching for friendly scenarios that may explain the formation of the giant planet detected in this system. For low-mass protoplanetary discs, we find that a low-eccentricity static disc aligned with the binary yields impact velocities between planetesimals below the disruption threshold. All other scenarios appear hostile to planetary formation.

  4. Seeking the perfect alignment

    CERN Multimedia

    2002-01-01

    The first full-scale tests of the ATLAS Muon Spectrometer are about to begin in Prévessin. The set-up includes several layers of Monitored Drift Tubes Chambers (MDTs) and will allow tests of the performance of the detectors and of their highly accurate alignment system.   Monitored Drift Chambers in Building 887 in Prévessin, where they are just about to be tested. Muon chambers are keeping the ATLAS Muon Spectrometer team quite busy this summer. Now that most people go on holiday, the beam and alignment tests for these chambers are just starting. These chambers will measure with high accuracy the momentum of high-energy muons, and this implies very demanding requirements for their alignment. The MDT chambers consist of drift tubes, which are gas-filled metal tubes, 3 cm in diameter, with wires running down their axes. With high voltage between the wire and the tube wall, the ionisation due to traversing muons is detected as electrical pulses. With careful timing of the pulses, the position of the muon t...

  5. Diagnosing the tight building syndrome.

    Science.gov (United States)

    Rogers, S A

    1987-12-01

    Formaldehyde is but one of many chemicals capable of causing the tight building syndrome or environmentally induced illness (EI). The spectrum of symptoms it may induce includes attacks of headache, flushing, laryngitis, dizziness, nausea, extreme weakness, arthralgia, unwarranted depression, dysphonia, exhaustion, inability to think clearly, arrhythmia or muscle spasms. The nonspecificity of such symptoms can baffle physicians from many specialties. Presented herein is a simple office method for demonstrating that formaldehyde is among the etiologic agents triggering these symptoms. The very symptoms that patients complain of can be provoked within minutes, and subsequently abolished, with an intradermal injection of the appropriate strength of formaldehyde. This injection aids in convincing the patient of the cause of the symptoms so he can initiate measures to bring his disease under control.

  6. Fingerprinting with Equiangular Tight Frames

    CERN Document Server

    Mixon, Dustin G; Kiyavash, Negar; Fickus, Matthew

    2011-01-01

    Digital fingerprinting is a framework for marking media files, such as images, music, or movies, with user-specific signatures to deter illegal distribution. Multiple users can collude to produce a forgery that can potentially overcome a fingerprinting system. This paper proposes an equiangular tight frame fingerprint design which is robust to such collusion attacks. We motivate this design by considering digital fingerprinting in terms of compressed sensing. The attack is modeled as linear averaging of multiple marked copies before adding a Gaussian noise vector. The content owner can then determine guilt by exploiting correlation between each user's fingerprint and the forged copy. The worst-case error probability of this detection scheme is analyzed and bounded. Simulation results demonstrate the average-case performance is similar to the performance of orthogonal and simplex fingerprint designs, while accommodating several times as many users.

  7. Why tight-binding theory?

    Science.gov (United States)

    Harrison, Walter A.

    2002-12-01

    In the context of computational physics other methods are more accurate, but tight-binding theory allows very direct physical interpretation and is simple enough to allow much more realistic treatments beyond the local density approximation. We address several important questions of this last category: How does the gap enhancement from Coulomb correlations vary from material to material? Should the enhanced gap be used for calculating the dielectric constant? For calculating the effective mass in k-dot-p theory? How valid is the scissors approximation? How does one line up bands at an interface? How should we match the envelope function at interfaces in effective-mass theory? Why can the resulting quantum-well states seem to violate the uncertainty principle? How should f-shell electrons be treated when they are intermediate between band-like and core-like? The answers to all of these questions are given and discussed.

  8. Invasive tightly coupled processor arrays

    CERN Document Server

    LARI, VAHID

    2016-01-01

    This book introduces new massively parallel computer (MPSoC) architectures called invasive tightly coupled processor arrays. It proposes strategies, architecture designs, and programming interfaces for invasive TCPAs that allow invading and subsequently executing loop programs with strict requirements or guarantees of non-functional execution qualities such as performance, power consumption, and reliability. For the first time, such a configurable processor array architecture consisting of locally interconnected VLIW processing elements can be claimed by programs, either in full or in part, using the principle of invasive computing. Invasive TCPAs provide unprecedented energy efficiency for the parallel execution of nested loop programs by avoiding any global memory access such as GPUs and may even support loops with complex dependencies such as loop-carried dependencies that are not amenable to parallel execution on GPUs. For this purpose, the book proposes different invasion strategies for claiming a desire...

  9. Diagnosing the tight building syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, S.A.

    1987-12-01

    Formaldehyde is but one of many chemicals capable of causing the tight building syndrome or environmentally induced illness (EI). The spectrum of symptoms it may induce includes attacks of headache, flushing, laryngitis, dizziness, nausea, extreme weakness, arthralgia, unwarranted depression, dysphonia, exhaustion, inability to think clearly, arrhythmia or muscle spasms. The nonspecificity of such symptoms can baffle physicians from many specialties. Presented herein is a simple office method for demonstrating that formaldehyde is among the etiologic agents triggering these symptoms. The very symptoms that patients complain of can be provoked within minutes, and subsequently abolished, with an intradermal injection of the appropriate strength of formaldehyde. This injection aids in convincing the patient of the cause of the symptoms so he can initiate measure to bring his disease under control.

  10. LCLS Undulator Commissioning, Alignment, and Performance

    Energy Technology Data Exchange (ETDEWEB)

    Nuhn, Heinz-Dieter

    2009-10-30

    The LCLS x-ray FEL has recently achieved its 1.5-Angstrom lasing and saturation goals upon first trial. This was achieved as a result of a thorough pre-beam checkout, both traditional and beam-based component alignment techniques, and high electron beam brightness. The x-ray FEL process demands very tight tolerances on the straightness of the electron beam trajectory (<5 {micro}m) through the LCLS undulator system. Tight, but less stringent tolerances of {approx}100 {micro}m rms were met for the transverse placement of the individual undulator segments with respect to the beam axis. The tolerances for electron beam straightness can only be met through a beam-based alignment (BBA) method, which is implemented using large electron energy variations and sub-micron resolution cavity beam position monitors (BPM), with precise conventional alignment used to set the starting conditions. Precision-fiducialization of components mounted on remotely adjustable girders, and special beam-finder wires (BFW) at each girder have been used to meet these challenging alignment tolerances. Longer-term girder movement due to ground motion and temperature changes are being monitored, continuously, by a unique stretched wire and hydrostatic level Alignment Diagnostics System (ADS).

  11. Global Coal Trade. From Tightness to Oversupply

    International Nuclear Information System (INIS)

    Over the past four years, international coal trade has been reshaped by China's surging imports. China, which was still a net exporter in 2008, became the world's first coal importer in 2011, taking over the position that Japan has occupied for three decades. Its imports have continued their rising trend and reached a record level in 2012, despite the country's economic slowdown. China imported 289 million tons of coal in 2012, up 30% over 2011. It now accounts for 23% of global imports. Although China is the world's largest coal producer, several factors have contributed to the sudden rise in its imports, including the higher cost of domestic coal relative to international prices and bottlenecks in transporting domestic coal to south-eastern provinces. More recently, another event shook the international coal business: the United States have been back on the market. The collapse of U.S. gas prices, to $4/million Btu in 2011 and even $2.75/million Btu in 2012, linked with the 'shale gas revolution', has made coal uncompetitive in the electricity sector, its main outlet on the U.S. market. U.S. coal demand dropped 4% in 2011 and 11% in 2012. The reduction in domestic demand has forced U.S. miners to look for overseas outlets. Their exports surged by 31% in 2011 and 16% in 2012. They reached 112 million tons in 2012, more than twice the level of 2009. The United States, which almost disappeared from the international steam coal market in the 2000's, have regained a larger share of the total coal export market, 9% in 2012, against 6% in 2009. These developments, although not directly linked, have a huge impact on the global market and pricing of coal. Chinese imports have helped the market to quickly recover from its low level of 2008-2009. The speed and magnitude of China's coal imports even shifts the market from a sluggish to a tight situation. Prices started to rise after their collapse in the second half of 2008 caused by the economic and financial crisis

  12. Gas laser tube and method of fabricating same

    International Nuclear Information System (INIS)

    An improved gas laser tube is fabricated by counter boring the ends of a tubular aluminum extrusion having an inner tubular portion supported from an outer tubular portion via the intermediary of a plurality of radially directed support vanes or legs. Metallic transverse walls are sealed across the ends of the tubular extrusion to define the ends of a gas tight metallic envelope. An electrically insulative glow discharge tube is axially disposed within and supported by the inner tubular portion of the extrusion in axial alignment with an optical resonator of the laser tube. (U.S.)

  13. Geometry Description of Gas Flooding′Oil Bank′in Tight Reservoirs%低渗透油藏气驱“油墙”几何形态描述

    Institute of Scientific and Technical Information of China (English)

    王高峰; 张云海; 郑国臣; 汪艳勇

    2015-01-01

    在界定气驱类型的基础上,阐述了高压注气“油墙”形成过程。将气驱“油墙”形成机制概括为“差异化运移”和“加速凝析加积”;并首次区分出控制气驱见效高峰期生产效果的“先导性显式油墙”和“伴随性隐式油墙”两种类型。基于简化实际气驱过程的“三步近似法”、物质平衡原理和低渗透油藏气驱增产倍数等概念,给出了见气见效时单井组内“先导性显式油墙”的形态、宽度、高度、面积、周长、体积等几何产状要素的定义和描述方法。进一步提出“油墙集中采出体积”和“油墙集中采出时间”概念及其计算方法,为见效高峰期持续时间估算和气驱开发阶段定量划分提供了理论依据,也为注气开发方案编制提供了必要依据。%Based on the definition of the types of gas flooding, the forming of′oil bank′is described during the high pressure gas injection process.The gas drive"oil bank"formation mechanism is summed up as′differentiation in migration of crude oil components′and ′accelerated accretion of condensation near gas flooding frontier′.Two types of oil bank, ′leading explicit oil bank′and ′following implicit oil bank′are distinguished for the first time which control the dynamic performance of peak oil producing stage of gas flooding.On the basis of the concepts,′three-step method approximation of real gas flooding process′, material balance Principle and ′oil production rate multiplier due to gas flooding′, the geometric shape, width, height, area, circumference and volume of the′explic-it oil bank′within a well pattern are defined and the calculation method of these geometric occurrence elements are also provided.Further, two new concepts,′centralized recovery volume of oil bank′and′centralized recovery time of oil bank′are postulated, which will be useful for estimating the duration of peak oil production

  14. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez.

    Since June of 2009, the muon alignment group has focused on providing new alignment constants and on finalizing the hardware alignment reconstruction. Alignment constants for DTs and CSCs were provided for CRAFT09 data reprocessing. For DT chambers, the track-based alignment was repeated using CRAFT09 cosmic ray muons and validated using segment extrapolation and split cosmic tools. One difference with respect to the previous alignment is that only five degrees of freedom were aligned, leaving the rotation around the local x-axis to be better determined by the hardware system. Similarly, DT chambers poorly aligned by tracks (due to limited statistics) were aligned by a combination of photogrammetry and hardware-based alignment. For the CSC chambers, the hardware system provided alignment in global z and rotations about local x. Entire muon endcap rings were further corrected in the transverse plane (global x and y) by the track-based alignment. Single chamber track-based alignment suffers from poor statistic...

  15. Lifting scheme of symmetric tight wavelets frames

    Institute of Scientific and Technical Information of China (English)

    ZHUANG BoJin; YUAN WeiTao; PENG LiZhong

    2008-01-01

    This paper proposes a method to realize the lifting scheme of tight frame wavelet filters. As for 4-channel tight frame wavelet filter, the tight frame transforms' ma-trix is 2×4, but the lifting scheme transforms' matrix must be 4×4. And in the case of 3-channel tight frame wavelet filter, the transforms' matrix is 2×3, but the lifting scheme transforms' matrix must be 3×3. In order to solve this problem, we intro-duce two concepts: transferred polyphase matrix for 4-channel filters and trans-ferred unitary matrix for 3-channel filters. The transferred polyphase matrix is sym-metric/antisymmetric. Thus, we use this advantage to realize the lifting scheme.

  16. Complex Hadamard matrices and Equiangular Tight Frames

    CERN Document Server

    Szöll\\Hosi, Ferenc

    2011-01-01

    In this paper we give a new construction of parametric families of complex Hadamard matrices of square orders, and connect them to equiangular tight frames. The results presented here generalize some of the recent ideas of Bodmann et al. and extend the list of known equiangular tight frames. In particular, a (36,21) frame coming from a nontrivial cube root signature matrix is obtained for the first time.

  17. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez and J. Pivarski

    2011-01-01

    Alignment efforts in the first few months of 2011 have shifted away from providing alignment constants (now a well established procedure) and focussed on some critical remaining issues. The single most important task left was to understand the systematic differences observed between the track-based (TB) and hardware-based (HW) barrel alignments: a systematic difference in r-φ and in z, which grew as a function of z, and which amounted to ~4-5 mm differences going from one end of the barrel to the other. This difference is now understood to be caused by the tracker alignment. The systematic differences disappear when the track-based barrel alignment is performed using the new “twist-free” tracker alignment. This removes the largest remaining source of systematic uncertainty. Since the barrel alignment is based on hardware, it does not suffer from the tracker twist. However, untwisting the tracker causes endcap disks (which are aligned ...

  18. Study and Development of a Laser Based Alignment System

    CERN Multimedia

    Stern, G

    2014-01-01

    CLIC (Compact Linear Collider) has tight requirements regarding pre-alignment of beam related components: 10 µm accuracy over a sliding window of 200 m along the 20 km of linac. To perform such an alignment, a new system is proposed combining laser beam as straight line reference and camera/shutter assemblies as sensors. The poster describes the alignment system and shows results regarding laser pointing stability with respect to time, shutter type, distance and environment. These results give a frame for future building and calibrating of sensors.

  19. Fast statistical alignment.

    Directory of Open Access Journals (Sweden)

    Robert K Bradley

    2009-05-01

    Full Text Available We describe a new program for the alignment of multiple biological sequences that is both statistically motivated and fast enough for problem sizes that arise in practice. Our Fast Statistical Alignment program is based on pair hidden Markov models which approximate an insertion/deletion process on a tree and uses a sequence annealing algorithm to combine the posterior probabilities estimated from these models into a multiple alignment. FSA uses its explicit statistical model to produce multiple alignments which are accompanied by estimates of the alignment accuracy and uncertainty for every column and character of the alignment--previously available only with alignment programs which use computationally-expensive Markov Chain Monte Carlo approaches--yet can align thousands of long sequences. Moreover, FSA utilizes an unsupervised query-specific learning procedure for parameter estimation which leads to improved accuracy on benchmark reference alignments in comparison to existing programs. The centroid alignment approach taken by FSA, in combination with its learning procedure, drastically reduces the amount of false-positive alignment on biological data in comparison to that given by other methods. The FSA program and a companion visualization tool for exploring uncertainty in alignments can be used via a web interface at http://orangutan.math.berkeley.edu/fsa/, and the source code is available at http://fsa.sourceforge.net/.

  20. Fast statistical alignment.

    Science.gov (United States)

    Bradley, Robert K; Roberts, Adam; Smoot, Michael; Juvekar, Sudeep; Do, Jaeyoung; Dewey, Colin; Holmes, Ian; Pachter, Lior

    2009-05-01

    We describe a new program for the alignment of multiple biological sequences that is both statistically motivated and fast enough for problem sizes that arise in practice. Our Fast Statistical Alignment program is based on pair hidden Markov models which approximate an insertion/deletion process on a tree and uses a sequence annealing algorithm to combine the posterior probabilities estimated from these models into a multiple alignment. FSA uses its explicit statistical model to produce multiple alignments which are accompanied by estimates of the alignment accuracy and uncertainty for every column and character of the alignment--previously available only with alignment programs which use computationally-expensive Markov Chain Monte Carlo approaches--yet can align thousands of long sequences. Moreover, FSA utilizes an unsupervised query-specific learning procedure for parameter estimation which leads to improved accuracy on benchmark reference alignments in comparison to existing programs. The centroid alignment approach taken by FSA, in combination with its learning procedure, drastically reduces the amount of false-positive alignment on biological data in comparison to that given by other methods. The FSA program and a companion visualization tool for exploring uncertainty in alignments can be used via a web interface at http://orangutan.math.berkeley.edu/fsa/, and the source code is available at http://fsa.sourceforge.net/. PMID:19478997

  1. Alignments of galaxies and halos in hydrodynamical simulations

    Science.gov (United States)

    Pahwa, Isha; Libeskind, Noam I.

    2016-10-01

    We use a 200 h -1Mpc cosmological hydrodynamical simulation to examine the alignments of galaxies with respect to the host halo. We do separate study for the different components of the halo, such as stars, gas and dark matter. We show that angular momentum of gas is more aligned with the angular momentum of host halo compared with the stellar component.

  2. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    2010-01-01

    The main developments in muon alignment since March 2010 have been the production, approval and deployment of alignment constants for the ICHEP data reprocessing. In the barrel, a new geometry, combining information from both hardware and track-based alignment systems, has been developed for the first time. The hardware alignment provides an initial DT geometry, which is then anchored as a rigid solid, using the link alignment system, to a reference frame common to the tracker. The “GlobalPositionRecords” for both the Tracker and Muon systems are being used for the first time, and the initial tracker-muon relative positioning, based on the link alignment, yields good results within the photogrammetry uncertainties of the Tracker and alignment ring positions. For the first time, the optical and track-based alignments show good agreement between them; the optical alignment being refined by the track-based alignment. The resulting geometry is the most complete to date, aligning all 250 DTs, ...

  3. Direct comparative study on the energy level alignments in unoccupied/occupied states of organic semiconductor/electrode interface by constructing in-situ photoemission spectroscopy and Ar gas cluster ion beam sputtering integrated analysis system

    International Nuclear Information System (INIS)

    Through the installation of electron gun and photon detector, an in-situ photoemission and damage-free sputtering integrated analysis system is completely constructed. Therefore, this system enables to accurately characterize the energy level alignments including unoccupied/occupied molecular orbital (LUMO/HOMO) levels at interface region of organic semiconductor/electrode according to depth position. Based on Ultraviolet Photoemission Spectroscopy (UPS), Inverse Photoemission Spectroscopy (IPES), and reflective electron energy loss spectroscopy, the occupied/unoccupied state of in-situ deposited Tris[4-(carbazol-9-yl)phenyl]amine (TCTA) organic semiconductors on Au (ELUMO: 2.51 eV and EHOMO: 1.35 eV) and Ti (ELUMO: 2.19 eV and EHOMO: 1.69 eV) electrodes are investigated, and the variation of energy level alignments according to work function of electrode (Au: 4.81 eV and Ti: 4.19 eV) is clearly verified. Subsequently, under the same analysis condition, the unoccupied/occupied states at bulk region of TCTA/Au structures are characterized using different Ar gas cluster ion beam (Ar GCIB) and Ar ion sputtering processes, respectively. While the Ar ion sputtering process critically distorts both occupied and unoccupied states in UPS/IPES spectra, the Ar GCIB sputtering process does not give rise to damage on them. Therefore, we clearly confirm that the in-situ photoemission spectroscopy in combination with Ar GCIB sputtering allows of investigating accurate energy level alignments at bulk/interface region as well as surface region of organic semiconductor/electrode structure.

  4. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    Z. Szillasi and G. Gomez.

    2013-01-01

    When CMS is opened up, major components of the Link and Barrel Alignment systems will be removed. This operation, besides allowing for maintenance of the detector underneath, is needed for making interventions that will reinforce the alignment measurements and make the operation of the alignment system more reliable. For that purpose and also for their general maintenance and recalibration, the alignment components will be transferred to the Alignment Lab situated in the ISR area. For the track-based alignment, attention is focused on the determination of systematic uncertainties, which have become dominant, since now there is a large statistics of muon tracks. This will allow for an improved Monte Carlo misalignment scenario and updated alignment position errors, crucial for high-momentum muon analysis such as Z′ searches.

  5. 苏里格气田西区致密砂岩储层地层水分布特征%Distribution of formation water in tight sandstone reservoirs of western Sulige gas field, Ordos Basin

    Institute of Scientific and Technical Information of China (English)

    王晓梅; 赵靖舟; 刘新社; 范立勇

    2012-01-01

    The criteria for an acceptable formation watercut level in the western Sulige gasfield in Ordos Basin can be summarized as salinity≥50g/L,sodium-chlorine ratio <0. 5 ,sodium-calcium ratio < 1 and fracturing fluid flowback rate ≥3100%. Based on a comprehensive analysis of water formation chemical characteristics, hydrogen and oxygen isotopes as well as trace element" Br" ,the paper concludes that the formation water in the western Sulige gasfield was of continental sedimentary origin and experienced extensive water-rock interaction and evaporation processes. The analysis also indicates that sealing condition for the formation water in the Upper Paleozoic is good, thus which is favorable for gas accumulation and preservation. Further analysis in combination with consideration of hydrocarbon accumulation elements such as source rocks, reservoir and cap rocks reveals that the formation water is residual water from the process of weak dynamic hydrocarbon accumulation. The complicated gas-water distribution pattern is caused by reservoir heterogeneity and microstructures on the background of low hydrocarbon-generating intensity and low tectonic position. The formation water of high salinity in the eastern Ordos Basin is suggested to be related to the water-rock process of the Ordovician salinastone.%鄂尔多斯盆地苏里格气田西区正常地层水的判别标准为:矿化度≥50 g/L,钠氯系数(rNa+/rCl-)<0.5,钠钙系数(rNa+ /rCa2+)<1,压裂液返排率≥100%.通过地层水化学特征、氢氧同位素和微量元素溴的综合分析认为,苏里格气田西区地层水来源于经过了强烈水-岩作用和蒸发浓缩作用的陆相沉积成因水.确认苏里格气田上古生界地层水封闭条件好,有利于天然气聚集和保存.进一步结合该区烃源岩、储层和盖层等成藏要素分析认为,该区地层水主要是弱动力成藏过程中的残余地层水,复杂的气-水分布源于低生烃强度和低构造位置

  6. High accuracy alignment facility for the receiver and transmitter of the BepiColombo Laser Altimeter

    OpenAIRE

    Chakraborty, Sumita; Affolter, Michael; Gunderson, Kurt; Neubert, Jakob; Thomas, Nicolas; Beck, Thomas; Gerber, Michael; Graf, Stefan; Piazza, Daniele; Pommerol, Antoine; Röthlisberger, Guillaume; Seiferlin, Karsten

    2012-01-01

    The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group. We list the different steps o...

  7. 川西坳陷中段上三叠统须二段致密砂岩孔隙度演化史%Porosity Evolution of Tight Gas Sand of the Second Member of Xujiahe Formation of Upper Triassic, Western Sichuan Depression

    Institute of Scientific and Technical Information of China (English)

    陈冬霞; 庞雄奇; 杨克明; 杨宇; 叶军

    2012-01-01

    The formation of tight gas sand of the second member of Xujiahe Formation of Upper Triassic, western Sichuan depression is controlled by multiple-stage structural movements, strong diagenetic modification, which leads to the porosity evolution being the key to define the genetic types of gas reservoir and to improve gas exploration. Based on the studying of diagenesis by observing under microscope and analyzing under scanning e-lectron microprobe and cathodeluminescence, the diagenetic series and diagenetic stages are constructed by combination of measure of homogenization temperatures of inclusions, and paleotemperature grades. Porosity evolution models of each diagenetic stage are quantitatively established by fully consideration of the effect of lithofacies like granularity and sorting on the primary porosity in sedimentary process, and the effect of diagenesis such as compaction, cementation and corrosion on porosity evolution. The quantitative research shows that the tighten time of the tight gas sand of the second member of Xujiahe Formation is about the early stage of late diagenesis corresponding to the early stage of Late Jurassic. The analysis also indicates that differential lithofacies and diagenesis of gas reservoir result in the difference of tighten time of sand in gas reservoir.%川西坳陷深层上三叠统须家河组经历的地史时间长,构造期次多,成岩作用改造普遍,储层致密化严重,导致致密砂岩气藏成因机制研究困难,其中孔隙度演化史的研究是该区致密气藏成因类型的判识和天然气勘探的关键.在利用显微镜观察、扫描电镜分析、阴极发光分析等认识了储层成岩作用特征的基础上,结合自生矿物中流体包裹体的均一化温度和古地温梯度等,建立了须二段储层的成岩作用序列,并确定了成岩矿物形成时间.在充分考虑沉积过程中的粒度、分选性等岩相特征对原生孔隙的影响,及压实作用、胶结和溶蚀

  8. Current trends in salivary gland tight junctions.

    Science.gov (United States)

    Baker, Olga J

    2016-01-01

    Tight junctions form a continuous intercellular barrier between epithelial cells that is required to separate tissue spaces and regulate selective movement of solutes across the epithelium. They are composed of strands containing integral membrane proteins (e.g., claudins, occludin and tricellulin, junctional adhesion molecules and the coxsackie adenovirus receptor). These proteins are anchored to the cytoskeleton via scaffolding proteins such as ZO-1 and ZO-2. In salivary glands, tight junctions are involved in polarized saliva secretion and barrier maintenance between the extracellular environment and the glandular lumen. This review seeks to provide an overview of what is currently known, as well as the major questions and future research directions, regarding tight junction expression, organization and function within salivary glands. PMID:27583188

  9. Characterization of an Upper Permian tight aas reservoir : a multidisciplinary, multiscale analysis from the Rotliegend, Northern Germany

    OpenAIRE

    Antrett, Philipp

    2011-01-01

    This thesis describes a multidisciplinary, multiscale approach to the analysis of tight gas reservoirs. It focused initially on the facies architecture of a Permian tight gas field in the Southern Permian Basin (SPB), East Frisia, Northern Germany. To improve field development, 3D seismic data, wireline and core data were compared to a reservoir analogue in the Panamint Valley, California, United States. Depositional environments of the Permian Upper Rotliegend II included perennial saline la...

  10. Fast Statistical Alignment

    OpenAIRE

    Bradley, Robert K.; Adam Roberts; Michael Smoot; Sudeep Juvekar; Jaeyoung Do; Colin Dewey; Ian Holmes; Lior Pachter

    2009-01-01

    We describe a new program for the alignment of multiple biological sequences that is both statistically motivated and fast enough for problem sizes that arise in practice. Our Fast Statistical Alignment program is based on pair hidden Markov models which approximate an insertion/deletion process on a tree and uses a sequence annealing algorithm to combine the posterior probabilities estimated from these models into a multiple alignment. FSA uses its explicit statistical model to produce multi...

  11. Horizontal carbon nanotube alignment.

    Science.gov (United States)

    Cole, Matthew T; Cientanni, Vito; Milne, William I

    2016-09-21

    The production of horizontally aligned carbon nanotubes offers a rapid means of realizing a myriad of self-assembled near-atom-scale technologies - from novel photonic crystals to nanoscale transistors. The ability to reproducibly align anisotropic nanostructures has huge technological value. Here we review the present state-of-the-art in horizontal carbon nanotube alignment. For both in and ex situ approaches, we quantitatively assess the reported linear packing densities alongside the degree of alignment possible for each of these core methodologies. PMID:27546174

  12. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    2010-01-01

    Most of the work in muon alignment since December 2009 has focused on the geometry reconstruction from the optical systems and improvements in the internal alignment of the DT chambers. The barrel optical alignment system has progressively evolved from reconstruction of single active planes to super-planes (December 09) to a new, full barrel reconstruction. Initial validation studies comparing this full barrel alignment at 0T with photogrammetry provide promising results. In addition, the method has been applied to CRAFT09 data, and the resulting alignment at 3.8T yields residuals from tracks (extrapolated from the tracker) which look smooth, suggesting a good internal barrel alignment with a small overall offset with respect to the tracker. This is a significant improvement, which should allow the optical system to provide a start-up alignment for 2010. The end-cap optical alignment has made considerable progress in the analysis of transfer line data. The next set of alignment constants for CSCs will there...

  13. Orthodontics and Aligners

    Science.gov (United States)

    ... Repairing Chipped Teeth Teeth Whitening Tooth-Colored Fillings Orthodontics and Aligners Straighten teeth for a healthier smile. Orthodontics When consumers think about orthodontics, braces are the ...

  14. Classifying tight Weyl-Heisenberg frames

    DEFF Research Database (Denmark)

    Cazsazza, P.; Janssen, A. J. E. M.; Christensen, Ole

    1999-01-01

    A Weyl-Heisenberg frame for L^2(R) is a frame consisting of translates and modulates of a fixed function. In this paper we give necessary and sufficient conditions for this family to form a tight WH-frame. This allows us to write down explicitly all functions g for which all translates...

  15. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez

    Since December, the muon alignment community has focused on analyzing the data recorded so far in order to produce new DT and CSC Alignment Records for the second reprocessing of CRAFT data. Two independent algorithms were developed which align the DT chambers using global tracks, thus providing, for the first time, a relative alignment of the barrel with respect to the tracker. These results are an important ingredient for the second CRAFT reprocessing and allow, for example, a more detailed study of any possible mis-modelling of the magnetic field in the muon spectrometer. Both algorithms are constructed in such a way that the resulting alignment constants are not affected, to first order, by any such mis-modelling. The CSC chambers have not yet been included in this global track-based alignment due to a lack of statistics, since only a few cosmics go through the tracker and the CSCs. A strategy exists to align the CSCs using the barrel as a reference until collision tracks become available. Aligning the ...

  16. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    2011-01-01

    The Muon Alignment work now focuses on producing a new track-based alignment with higher track statistics, making systematic studies between the results of the hardware and track-based alignment methods and aligning the barrel using standalone muon tracks. Currently, the muon track reconstruction software uses a hardware-based alignment in the barrel (DT) and a track-based alignment in the endcaps (CSC). An important task is to assess the muon momentum resolution that can be achieved using the current muon alignment, especially for highly energetic muons. For this purpose, cosmic ray muons are used, since the rate of high-energy muons from collisions is very low and the event statistics are still limited. Cosmics have the advantage of higher statistics in the pT region above 100 GeV/c, but they have the disadvantage of having a mostly vertical topology, resulting in a very few global endcap muons. Only the barrel alignment has therefore been tested so far. Cosmic muons traversing CMS from top to bottom are s...

  17. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    Gervasio Gomez

    The main progress of the muon alignment group since March has been in the refinement of both the track-based alignment for the DTs and the hardware-based alignment for the CSCs. For DT track-based alignment, there has been significant improvement in the internal alignment of the superlayers inside the DTs. In particular, the distance between superlayers is now corrected, eliminating the residual dependence on track impact angles, and good agreement is found between survey and track-based corrections. The new internal geometry has been approved to be included in the forthcoming reprocessing of CRAFT samples. The alignment of DTs with respect to the tracker using global tracks has also improved significantly, since the algorithms use the latest B-field mapping, better run selection criteria, optimized momentum cuts, and an alignment is now obtained for all six degrees of freedom (three spatial coordinates and three rotations) of the aligned DTs. This work is ongoing and at a stage where we are trying to unders...

  18. Real Interference Alignment

    CERN Document Server

    Motahari, Abolfazl Seyed; Maddah-Ali, Mohammad-Ali; Khandani, Amir Keyvan

    2010-01-01

    In this paper, we show that the total Degrees-Of-Freedoms (DOF) of the $K$-user Gaussian Interference Channel (GIC) can be achieved by incorporating a new alignment technique known as \\emph{real interference alignment}. This technique compared to its ancestor \\emph{vector interference alignment} performs on a single real line and exploits the properties of real numbers to provide optimal signaling. The real interference alignment relies on a new coding scheme in which several data streams having fractional multiplexing gains are sent by transmitters and interfering streams are aligned at receivers. The coding scheme is backed up by a recent result in the field of Diophantine approximation, which states that the convergence part of the Khintchine-Groshev theorem holds for points on non-degenerate manifolds.

  19. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez

    2011-01-01

    A new set of muon alignment constants was approved in August. The relative position between muon chambers is essentially unchanged, indicating good detector stability. The main changes concern the global positioning of the barrel and of the endcap rings to match the new Tracker geometry. Detailed studies of the differences between track-based and optical alignment of DTs have proven to be a valuable tool for constraining Tracker alignment weak modes, and this information is now being used as part of the alignment procedure. In addition to the “split-cosmic” analysis used to investigate the muon momentum resolution at high momentum, a new procedure based on reconstructing the invariant mass of di-muons from boosted Zs is under development. Both procedures show an improvement in the momentum precision of Global Muons with respect to Tracker-only Muons. Recent developments in track-based alignment include a better treatment of the tails of residual distributions and accounting for correla...

  20. Control rod housing alignment and repair method

    International Nuclear Information System (INIS)

    This patent describes a method for underwater welding of a control rod drive housing inserted through a stub tube to maintain requisite alignment and elevation of the top of the control rod drive housing to an overlying and corresponding aperture in a core plate as measured by an alignment device which determines the relative elevation and angularity with respect to the aperture. It comprises providing a welding cylinder dependent from the alignment device such that the elevation of the top of the welding cylinder is in a fixed relationship to the alignment device and is gas-proof; pressurizing the welding cylinder with inert welding gas sufficient to maintain the interior of the welding cylinder dry; lowering the welding cylinder through the aperture in the core plate by depending the cylinder with respect to the alignment device, the lowering including lowering through and adjusting the elevation relationship of the welding cylinder to the alignment device such that when the alignment device is in position to measure the elevation and angularity of the new control rod drive housing, the lower distal end of the welding cylinder extends below the upper periphery of the stub where welding is to occur; inserting a new control rod drive housing through the stub tube and positioning the control rod drive housing to a predetermined relationship to the anticipated final position of the control rod drive housing; providing welding implements transversely rotatably mounted interior of the welding cylinder relative to the alignment device such that the welding implements may be accurately positioned for dispensing weldment around the periphery of the top of the stub tube and at the side of the control rod drive housing; measuring the elevation and angularity of the control rod drive housing; and dispensing weldment along the top of the stub tube and at the side of the control rod drive housing

  1. Boundary effect on liquid invasion in tight gas reservoirs

    Directory of Open Access Journals (Sweden)

    Li Gao

    2015-01-01

    Full Text Available Liquid invasion is an important transport phenomenon in many geophysical and environmental applications. A new capillary model considering boundary effect is proposed to reveal its mechanism. The boundary fluid layer not only reduces the effective flow radius, but also changes the viscosity of fluid. Thus the capillary force and viscosity resistance increases, however, the increase of capillary force is faster than that of viscosity resistance, therefore the invasion front arrives at the critical distance earlier.

  2. Quantifying tight-gas sandstone permeability via critical path analysis

    Science.gov (United States)

    Rock permeability has been actively investigated over the past several decades by the geosciences community. However, its accurate estimation still presents significant technical challenges, especially in spatially complex rocks. In this letter, we apply critical path analysis (CPA) to estimate perm...

  3. Tight-binding treatment of conjugated polymers

    DEFF Research Database (Denmark)

    Lynge, Thomas Bastholm

    This PhD thesis concerns conjugated polymers which constitute a constantly growing research area. Today, among other things, conjugated polymers play a role in plastic based solar cells, photodetectors and light emitting diodes, and even today such plastic-based components constitute an alternative...... of tomorrow. This thesis specifically treats the three conjugated polymers trans-polyacetylene (tPA), poly(para-phenylene) (PPP) and poly(para-phe\\-nylene vinylene) (PPV). The present results, which are derived within the tight-binding model, are divided into two parts. In one part, analytic results...... are derived for the optical properties of the polymers expressed in terms of the optical susceptibility both in the presence and in the absence of a static electric field. In the other part, the cumputationally efficient Density Functional-based Tight-Binding (DFTB) model is applied to the description...

  4. 适用于致密气藏钻完井的新型超级13Cr油钻杆管材性能测试%Performance test of a new super 13Cr oil drill pipe used for tight gas reservoir drilling and complication

    Institute of Scientific and Technical Information of China (English)

    曾德智; 田刚; 施太和; 侯铎; 贾华明; 卢强; 赵鹏

    2014-01-01

    A new high strength super 13Cr oil drill pipe was developed for tight gas reservoir exploitation in Tarim oilfield .This paper studies the tensile property and impact property of S135 dirll pipe and new super 13Cr oil drill pipe by a material tensile testing machine and a instrumen-ted impact testing machine respectively .Their corrosion resistance to CO2 is also studied through high temperature and high pressure autoclave test .The results show that the ultimate strength of the new super 13Cr steel reaches 976 MPa ,with the yielding strength 937 MPa and elongation 19 .0% .Its impact energy reaches 162 .82 J .Compared with S135 steel ,the new super 13Cr steel has similar strength property and better impact property .Under the test condition ,the corrosion rate of the super 13Cr steel is 0 .003 6 mm/a in gas phase and 0 .039 4 mm/a in liquid phase . Therefore ,the new super 13Cr oil drill pipe can meet the requirement of drilling and well compli-cation .The new oil drill pipe could provide support for tight gas reservoir nitrogen drilling and well complication .%为满足塔里木致密气藏氮气钻完井需求,研制了一种新型高强度超级13Cr油钻杆。采用M TS试验机对新型超级13Cr油钻杆和S135钻杆的强度性能进行了对比测试;采用示波冲击试验机对新型超级13Cr油钻杆和S135钻杆的冲击性能进行了对比测试;采用高温高压釜对新型超级13Cr油钻杆和S135钻杆的耐CO2腐蚀性能进行了对比测试。结果表明:新型超级13Cr油钻杆具有良好力学性能和耐腐蚀性能,其屈服强度937 M Pa、抗拉强度976 M Pa、延伸率为21.5%、室温冲击功162.82 J。其拉伸性能与S135接近,冲击性能明显优于S135;模拟工况下,新型超级13C r油钻杆气相腐蚀速率0.0036 m m/a、液相腐蚀速率0.0394 m m/a。因此,新型超级13C r油钻杆既能满足钻井的需要又能满足完井开采的要求,可为含C O 2致密砂岩气田氮气钻完井作业提供支持。

  5. Inward Leakage in Tight-Fitting PAPRs

    OpenAIRE

    Frank C. Koh; Johnson, Arthur T.; Rehak, Timothy E.

    2011-01-01

    A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs), the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases,...

  6. Tight Binding Models in Cold Atoms Physics

    Science.gov (United States)

    Zakrzewski, J.

    2007-05-01

    Cold atomic gases placed in optical lattice potentials offer a unique tool to study simple tight binding models. Both the standard cases known from the condensed matter theory as well as novel situations may be addressed. Cold atoms setting allows for a precise control of parameters of the systems discussed, stimulating new questions and problems. The attempts to treat disorder in a controlled fashion are addressed in detail.

  7. What justifies the lack of alignment between natural gas and crude oil prices in the period 2006-2007; O que justifica o deslocamento entre os precos do gas natural e do petroleo no periodo 2006-2007

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Ana Lucia Vahia de; Pinelli, Marcelo Santos

    2008-07-01

    The objective of the work is to show that the mismatch between Brent and Henry Hub in the period 2006-2007 is mainly due to the local characteristics of natural gas market. After the beginning of 2008, the price of Henry Hub is increasing and returning to the long term relationship (nonlinear) with Brent. Even with local features, the natural gas market tends to be a market of tradable goods. (author.

  8. Terrestrial tight oil reservoir characteristics and Graded Resource Assessment in China

    Science.gov (United States)

    Wang, Shejiao; Wu, Xiaozhi; Guo, Giulin

    2016-04-01

    China. The porosity is 2-14%(average 5-10%)and the permeability is less than 1mD. The laboratory test and exploration practice confirmed that the oil content was positively related to physical property. The higher the porosity, the better the oil content will have. (3) Source rock and reservoir are superimposed. From the contact relationship of source rock and reservoir, the reservoir developed in the source rock has the advantage of capturing oil and gas, so the oil saturation can be as high as 70-80%. (4) The increased pressure caused by hydrocarbon generation and the connected fracture are the key factors for tight oil accumulation. The Fuyu tight oil formed underling source rock in Songliao Basin is a good example. The fracture system is the key factor for tight oil accumulation. Considering the strong heterogeneity of terrestrial tight oil reservoir in china, we create hierarchical resource abundance analogy, EUR analogy, cell element volumetric methods to evaluate tight oil resource potential. In order to find exploration "sweet spots", establishing tight oil resource classification evaluation standards are key steps to objectively evaluate tight oil resource distribution. The resource classification evaluation standards are established by the relationship analysis between reservoir properties and oil properties, and the correlation analysis between production, resource abundance, and reservoir thickness. The first-grade tight oil resource, which is recently available and can easily be developed, has following main parameters: the porosity is greater than 8%, thickness is over 10m, resource abundance is above 150,000 tons / km2, and pressure coefficient is greater than 1.3; The second-grade tight oil resource is currently unavailable, but with advanced technology can expected to be developed. The main parameters are as following: the porosity is 5% -8%, thickness is less than 5-10m, resource abundance is 50000-150000 tons / km2, the pressure coefficient is 1.0 to

  9. Alignment for CSR

    International Nuclear Information System (INIS)

    Cooled Storage Ring of Heavy Ion Research Facility in Lanzhou (HIRFL-CSR) belongs to China great scientific project in China. The alignment for it is very difficult because of very large area and very high accuracy. For the special case in HIRFL-CSR, some new methods and new instruments are used, including the construction of survey control network, the usage of laser tracker, and CSR alignment database system with applications developed to store and analyze data. The author describes the whole procedure of CSR alignment

  10. Galaxy Alignments: An Overview

    Science.gov (United States)

    Joachimi, Benjamin; Cacciato, Marcello; Kitching, Thomas D.; Leonard, Adrienne; Mandelbaum, Rachel; Schäfer, Björn Malte; Sifón, Cristóbal; Hoekstra, Henk; Kiessling, Alina; Kirk, Donnacha; Rassat, Anais

    2015-11-01

    The alignments between galaxies, their underlying matter structures, and the cosmic web constitute vital ingredients for a comprehensive understanding of gravity, the nature of matter, and structure formation in the Universe. We provide an overview on the state of the art in the study of these alignment processes and their observational signatures, aimed at a non-specialist audience. The development of the field over the past one hundred years is briefly reviewed. We also discuss the impact of galaxy alignments on measurements of weak gravitational lensing, and discuss avenues for making theoretical and observational progress over the coming decade.

  11. Galaxy alignments: An overview

    CERN Document Server

    Joachimi, Benjamin; Kitching, Thomas D; Leonard, Adrienne; Mandelbaum, Rachel; Schäfer, Björn Malte; Sifón, Cristóbal; Hoekstra, Henk; Kiessling, Alina; Kirk, Donnacha; Rassat, Anais

    2015-01-01

    The alignments between galaxies, their underlying matter structures, and the cosmic web constitute vital ingredients for a comprehensive understanding of gravity, the nature of matter, and structure formation in the Universe. We provide an overview on the state of the art in the study of these alignment processes and their observational signatures, aimed at a non-specialist audience. The development of the field over the past one hundred years is briefly reviewed. We also discuss the impact of galaxy alignments on measurements of weak gravitational lensing, and discuss avenues for making theoretical and observational progress over the coming decade.

  12. Discriminative Shape Alignment

    DEFF Research Database (Denmark)

    Loog, M.; de Bruijne, M.

    2009-01-01

    The alignment of shape data to a common mean before its subsequent processing is an ubiquitous step within the area shape analysis. Current approaches to shape analysis or, as more specifically considered in this work, shape classification perform the alignment in a fully unsupervised way......, not taking into account that eventually the shapes are to be assigned to two or more different classes. This work introduces a discriminative variation to well-known Procrustes alignment and demonstrates its benefit over this classical method in shape classification tasks. The focus is on two...

  13. Inventory non-conventional gas

    Energy Technology Data Exchange (ETDEWEB)

    Muntendam-Bos, A.G.; Wassing, B.B.T.; Ter Heege, J.H.; Van Bergen, F.; Schavemaker, Y.A.; Van Gessel, S.F.; De Jong, M.L.; Nelskamp, S.; Van Thienen-Visser, K.; Guasti, E.; Van den Belt; Marges, V.C. [TNO Built Environment and Geosciences, Utrecht (Netherlands)

    2009-10-15

    This report describes the results of the inventory for each non-conventional gas resource expected to be present in the Netherlands, which are: Tight Gas, Shallow gas, Coal bed Methane (CBM), Shale gas, Basin Centered Gas, Aquifer Gas and Stratigraphic traps.

  14. Characteristics and Mechanism of Permian Shanxi Tight Reservoir of Changbei Gas Field,Ordos Basin%鄂尔多斯盆地长北气田山西组二段低孔低渗储层特征及形成机理

    Institute of Scientific and Technical Information of China (English)

    孙海涛; 钟大康; 张湘宁; 柳慧林

    2011-01-01

    Changbei gas field is located in Yishan Slope of the northern center of the Ordos Basin,China.The main pay zone reservoir is Upper Paleozoic Lower Permian Shanxi P1S2 quartz arenite,which deposited in distributary channel of delta plain.The reservoir is low porosity low permeability tight reservoir with average porosity of 5.2% and average permeability of 0.7×10-3 μm2 in a current depth of 2 700~2 950 m.Integrated study on depositional environment,lithology,diagenesis and tectonic background has been conducted.The reasons cause this low porosity low permeability tight reservoir features are considered as the following two factors.(1) On one hand,the reservoir was deposited in a coaly bearing acid environment of deltaic distributary channel,the original pore water is acid water with non saturated calcium carbonate,which can not form earlier cementation within the sandstone reservoir.However,compaction has significantly reduce the original pore and pore volume.On the other hand,this acid diagenesis environment cause large amounts of secondary quartz cementation fill the pores left out during compaction of sandstone reservoir.This is the main reasons cause the low porosity low permeability tight reservoir features in the region.Observation from thin section indicate that calcium carbonate cementation is not developed in the pore of sandstone reservoir especially in the earlier stage,the average component of calcium carbonate cementation is 1%~3%,authigenic kaolinite cementation is well developed with an average component of 7%~10%,illite segmentation is also less developed 3%,secondary quartz cementation well develop,mostly reach Ⅱ—Ⅲ level with an average component of 5%~10%,some layer can reach 10%~18% and maximum is 23%,this phenomenon indicated the acid diagenesis environment of P1S2 quartz arenite reservoir in Changbei gas field.(2) Tectonic study indicated that Changbei gas field is located in Ordos Basin tectonically stable at the time

  15. A tight scaling relation of dark matter in galaxy clusters

    CERN Document Server

    Chan, Man Ho

    2014-01-01

    Recent studies in different types of galaxies reveal that the product of the central density and the core radius ($\\rho_cr_c$) is a constant. However, some empirical studies involving galaxy clusters suggest that the product $\\rho_cr_c$ depends weakly on the total dark halo mass. In this article, we re-analyse the hot gas data from 106 clusters and obtain a surprisingly tight scaling relation: $\\rho_c \\propto r_c^{-1.46 \\pm 0.16}$. This result generally agrees with the claims that $\\rho_cr_c$ is not a constant for all scales of structure. Moreover, this relation does not support the velocity-dependent cross section of dark matter if the core formation is due to the self-interaction of dark matter.

  16. Tidal alignment of galaxies

    CERN Document Server

    Blazek, Jonathan; Seljak, Uroš

    2015-01-01

    We develop an analytic model for galaxy intrinsic alignments (IA) based on the theory of tidal alignment. We calculate all relevant nonlinear corrections at one-loop order, including effects from nonlinear density evolution, galaxy biasing, and source density weighting. Contributions from density weighting are found to be particularly important and lead to bias dependence of the IA amplitude, even on large scales. This effect may be responsible for much of the luminosity dependence in IA observations. The increase in IA amplitude for more highly biased galaxies reflects their locations in regions with large tidal fields. We also consider the impact of smoothing the tidal field on halo scales. We compare the performance of this consistent nonlinear model in describing the observed alignment of luminous red galaxies with the linear model as well as the frequently used "nonlinear alignment model," finding a significant improvement on small and intermediate scales. We also show that the cross-correlation between ...

  17. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    Since September, the muon alignment system shifted from a mode of hardware installation and commissioning to operation and data taking. All three optical subsystems (Barrel, Endcap and Link alignment) have recorded data before, during and after CRAFT, at different magnetic fields and during ramps of the magnet. This first data taking experience has several interesting goals: •    study detector deformations and movements under the influence of the huge magnetic forces; •    study the stability of detector structures and of the alignment system over long periods, •    study geometry reproducibility at equal fields (specially at 0T and 3.8T); •    reconstruct B=0T geometry and compare to nominal/survey geometries; •    reconstruct B=3.8T geometry and provide DT and CSC alignment records for CMSSW. However, the main goal is to recons...

  18. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez

    2012-01-01

      A new muon alignment has been produced for 2012 A+B data reconstruction. It uses the latest Tracker alignment and single-muon data samples to align both DTs and CSCs. Physics validation has been performed and shows a modest improvement in stand-alone muon momentum resolution in the barrel, where the alignment is essentially unchanged from the previous version. The reference-target track-based algorithm using only collision muons is employed for the first time to align the CSCs, and a substantial improvement in resolution is observed in the endcap and overlap regions for stand-alone muons. This new alignment is undergoing the approval process and is expected to be deployed as part of a new global tag in the beginning of December. The pT dependence of the φ-bias in curvature observed in Monte Carlo was traced to a relative vertical misalignment between the Tracker and barrel muon systems. Moving the barrel as a whole to match the Tracker cures this pT dependence, leaving only the &phi...

  19. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    S. Szillasi

    2013-01-01

    The CMS detector has been gradually opened and whenever a wheel became exposed the first operation was the removal of the MABs, the sensor structures of the Hardware Barrel Alignment System. By the last days of June all 36 MABs have arrived at the Alignment Lab at the ISR where, as part of the Alignment Upgrade Project, they are refurbished with new Survey target holders. Their electronic checkout is on the way and finally they will be recalibrated. During LS1 the alignment system will be upgraded in order to allow more precise reconstruction of the MB4 chambers in Sector 10 and Sector 4. This requires new sensor components, so called MiniMABs (pictured below), that have already been assembled and calibrated. Image 6: Calibrated MiniMABs are ready for installation For the track-based alignment, the systematic uncertainties of the algorithm are under scrutiny: this study will enable the production of an improved Monte Carlo misalignment scenario and to update alignment position errors eventually, crucial...

  20. Incremental Alignment Manifold Learning

    Institute of Scientific and Technical Information of China (English)

    Zhi Han; De-Yu Meng; Zong-Sen Xu; Nan-Nan Gu

    2011-01-01

    A new manifold learning method, called incremental alignment method (IAM), is proposed for nonlinear dimensionality reduction of high dimensional data with intrinsic low dimensionality. The main idea is to incrementally align low-dimensional coordinates of input data patch-by-patch to iteratively generate the representation of the entire dataset. The method consists of two major steps, the incremental step and the alignment step. The incremental step incrementally searches neighborhood patch to be aligned in the next step, and the alignment step iteratively aligns the low-dimensional coordinates of the neighborhood patch searched to generate the embeddings of the entire dataset. Compared with the existing manifold learning methods, the proposed method dominates in several aspects: high efficiency, easy out-of-sample extension, well metric-preserving, and averting of the local minima issue. All these properties are supported by a series of experiments performed on the synthetic and real-life datasets. In addition, the computational complexity of the proposed method is analyzed, and its efficiency is theoretically argued and experimentally demonstrated.

  1. Atom laser dynamics in a tight waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Campo, A del; Lizuain, I; Muga, J G [Departamento de Quimica-Fisica, UPV-EHU, Apartado. 644, Bilbao (Spain); Pons, M [Departamento de Fisica Aplicada I, E.U.I.T. de Minas y Obras Publicas, UPV-EHU, 48901 Barakaldo (Spain); Moshinsky, M [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, 01000 Mexico D.F. (Mexico)], E-mail: adolfo.delcampo@ehu.es

    2008-02-15

    We study the transient dynamics that arise during the formation of an atom laser beam in a tight waveguide. The time dependent density profile develops a series of wiggles which are related to the diffraction in time phenomenon. The apodization of matter waves, which relies on the use of smooth aperture functions, allows to suppress such oscillations in a time interval, after which there is a revival of the diffraction in time. The revival time scale is directly related to the inverse of the harmonic trap frequency for the atom reservoir.

  2. Curriculum Alignment Research Suggests that Alignment Can Improve Student Achievement

    Science.gov (United States)

    Squires, David

    2012-01-01

    Curriculum alignment research has developed showing the relationship among three alignment categories: the taught curriculum, the tested curriculum and the written curriculum. Each pair (for example, the taught and the written curriculum) shows a positive impact for aligning those results. Following this, alignment results from the Third…

  3. MaxAlign: maximizing usable data in an alignment

    DEFF Research Database (Denmark)

    Oliveira, Rodrigo Gouveia; Sackett, Peter Wad; Pedersen, Anders Gorm

    2007-01-01

    BACKGROUND: The presence of gaps in an alignment of nucleotide or protein sequences is often an inconvenience for bioinformatical studies. In phylogenetic and other analyses, for instance, gapped columns are often discarded entirely from the alignment. RESULTS: MaxAlign is a program that optimizes...... the alignment prior to such analyses. Specifically, it maximizes the number of nucleotide (or amino acid) symbols that are present in gap-free columns - the alignment area - by selecting the optimal subset of sequences to exclude from the alignment. MaxAlign can be used prior to phylogenetic and bioinformatical...... analyses as well as in other situations where this form of alignment improvement is useful. In this work we test MaxAlign's performance in these tasks and compare the accuracy of phylogenetic estimates including and excluding gapped columns from the analysis, with and without processing with MaxAlign...

  4. Bioabsorbable thread for tight tying of bones.

    Science.gov (United States)

    Hattori, K; Tomita, N; Tamai, S; Ikada, Y

    2000-01-01

    The purpose of this research was to develop a bioabsorbable thread for tight fixation of fractured bones and to examine its mechanical performance in an in-vitro simulation study. The thread is a blend of bioabsorbable poly(L-lactic acid); (PLLA) and poly(epsilon-caprolactone); (PCL) fibers and can be tightly connected by fusion welding of the PCL fibers. The tying strength of the PLLA-PCL blend thread was 39.7 N, which was comparable to that of stainless steel wire. A testing machine was fabricated to measure the fatigue strength of the tying by simulating bone fixation. The results showed that metal wires always failed because of breakage within 25,000 loading cycles, whereas the blend threads did not fail until 50,000 loading cycles. The looseness of tying for simulated bone fixation by the blend thread was within 1mm even after 50 000 loading cycles. In-vivo testing using rats revealed that the blend thread did not cause any severe inflammatory reaction.

  5. Ergodic Secret Alignment

    CERN Document Server

    Bassily, Raef

    2010-01-01

    In this paper, we introduce two new achievable schemes for the fading multiple access wiretap channel (MAC-WT). In the model that we consider, we assume that perfect knowledge of the state of all channels is available at all the nodes in a causal fashion. Our schemes use this knowledge together with the time varying nature of the channel model to align the interference from different users at the eavesdropper perfectly in a one-dimensional space while creating a higher dimensionality space for the interfering signals at the legitimate receiver hence allowing for better chance of recovery. While we achieve this alignment through signal scaling at the transmitters in our first scheme (scaling based alignment (SBA)), we let nature provide this alignment through the ergodicity of the channel coefficients in the second scheme (ergodic secret alignment (ESA)). For each scheme, we obtain the resulting achievable secrecy rate region. We show that the secrecy rates achieved by both schemes scale with SNR as 1/2log(SNR...

  6. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    Gervasio Gomez

    2012-01-01

      The new alignment for the DT chambers has been successfully used in physics analysis starting with the 52X Global Tag. The remaining main areas of development over the next few months will be preparing a new track-based CSC alignment and producing realistic APEs (alignment position errors) and MC misalignment scenarios to match the latest muon alignment constants. Work on these items has been delayed from the intended timeline, mostly due to a large involvement of the muon alignment man-power in physics analyses over the first half of this year. As CMS keeps probing higher and higher energies, special attention must be paid to the reconstruction of very-high-energy muons. Recent muon POG reports from mid-June show a φ-dependence in curvature bias in Monte Carlo samples. This bias is observed already at the tracker level, where it is constant with muon pT, while it grows with pT as muon chamber information is added to the tracks. Similar studies show a much smaller effect in data, at le...

  7. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    M. Dallavalle

    2013-01-01

    A new Muon misalignment scenario for 2011 (7 TeV) Monte Carlo re-processing was re-leased. The scenario is based on running of standard track-based reference-target algorithm (exactly as in data) using single-muon simulated sample (with the transverse-momentum spectrum matching data). It used statistics similar to what was used for alignment with 2011 data, starting from an initially misaligned Muon geometry from uncertainties of hardware measurements and using the latest Tracker misalignment geometry. Validation of the scenario (with muons from Z decay and high-pT simulated muons) shows that it describes data well. The study of systematic uncertainties (dominant by now due to huge amount of data collected by CMS and used for muon alignment) is finalised. Realistic alignment position errors are being obtained from the estimated uncertainties and are expected to improve the muon reconstruction performance. Concerning the Hardware Alignment System, the upgrade of the Barrel Alignment is in progress. By now, d...

  8. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez

    2010-01-01

    For the last three months, the Muon Alignment group has focussed on providing a new, improved set of alignment constants for the end-of-year data reprocessing. These constants were delivered on time and approved by the CMS physics validation team on November 17. The new alignment incorporates several improvements over the previous one from March for nearly all sub-systems. Motivated by the loss of information from a hardware failure in May (an entire MAB was lost), the optical barrel alignment has moved from a modular, super-plane reconstruction, to a full, single loop calculation of the entire geometry for all DTs in stations 1, 2 and 3. This makes better use of the system redundancy, mitigating the effect of the information loss. Station 4 is factorised and added afterwards to make the system smaller (and therefore faster to run), and also because the MAB calibration at the MB4 zone is less precise. This new alignment procedure was tested at 0 T against photogrammetry resulting in precisions of the order...

  9. RNA Structural Alignments, Part I

    DEFF Research Database (Denmark)

    Havgaard, Jakob Hull; Gorodkin, Jan

    2014-01-01

    Simultaneous alignment and secondary structure prediction of RNA sequences is often referred to as "RNA structural alignment." A class of the methods for structural alignment is based on the principles proposed by Sankoff more than 25 years ago. The Sankoff algorithm simultaneously folds and aligns...

  10. Magnetically aligned supramolecular hydrogels.

    Science.gov (United States)

    Wallace, Matthew; Cardoso, Andre Zamith; Frith, William J; Iggo, Jonathan A; Adams, Dave J

    2014-12-01

    The magnetic-field-induced alignment of the fibrillar structures present in an aqueous solution of a dipeptide gelator, and the subsequent retention of this alignment upon transformation to a hydrogel upon the addition of CaCl2 or upon a reduction in solution pH is reported. Utilising the switchable nature of the magnetic field coupled with the slow diffusion of CaCl2 , it is possible to precisely control the extent of anisotropy across a hydrogel, something that is generally very difficult to do using alternative methods. The approach is readily extended to other compounds that form viscous solutions at high pH. It is expected that this work will greatly expand the utility of such low-molecular-weight gelators (LMWG) in areas where alignment is key. PMID:25345918

  11. Strategic Alignment of Business Intelligence

    OpenAIRE

    Cederberg, Niclas

    2010-01-01

    This thesis is about the concept of strategic alignment of business intelligence. It is based on a theoretical foundation that is used to define and explain business intelligence, data warehousing and strategic alignment. By combining a number of different methods for strategic alignment a framework for alignment of business intelligence is suggested. This framework addresses all different aspects of business intelligence identified as relevant for strategic alignment of business intelligence...

  12. Aligning Mental Representations

    DEFF Research Database (Denmark)

    Kano Glückstad, Fumiko

    2013-01-01

    This work introduces a framework that implements asymmetric communication theory proposed by Sperber and Wilson [1]. The framework applies a generalization model known as the Bayesian model of generalization (BMG) [2] for aligning knowledge possessed by two communicating parties. The work focuses...... on the application of the BMG to publicly available datasets, the Leuven natural concept database [3] representing semantic structures of domain knowledge possessed by individual subjects [3]. Results indicate that the BMG is potentially a model applicable to simulating the alignment of domain knowledge from...

  13. PILOT optical alignment

    Science.gov (United States)

    Longval, Y.; Mot, B.; Ade, P.; André, Y.; Aumont, J.; Baustista, L.; Bernard, J.-Ph.; Bray, N.; de Bernardis, P.; Boulade, O.; Bousquet, F.; Bouzit, M.; Buttice, V.; Caillat, A.; Charra, M.; Chaigneau, M.; Crane, B.; Crussaire, J.-P.; Douchin, F.; Doumayrou, E.; Dubois, J.-P.; Engel, C.; Etcheto, P.; Gélot, P.; Griffin, M.; Foenard, G.; Grabarnik, S.; Hargrave, P..; Hughes, A.; Laureijs, R.; Lepennec, Y.; Leriche, B.; Maestre, S.; Maffei, B.; Martignac, J.; Marty, C.; Marty, W.; Masi, S.; Mirc, F.; Misawa, R.; Montel, J.; Montier, L.; Narbonne, J.; Nicot, J.-M.; Pajot, F.; Parot, G.; Pérot, E.; Pimentao, J.; Pisano, G.; Ponthieu, N.; Ristorcelli, I.; Rodriguez, L.; Roudil, G.; Salatino, M.; Savini, G.; Simonella, O.; Saccoccio, M.; Tapie, P.; Tauber, J.; Torre, J.-P.; Tucker, C.

    2016-07-01

    PILOT is a balloon-borne astronomy experiment designed to study the polarization of dust emission in the diffuse interstellar medium in our Galaxy at wavelengths 240 μm with an angular resolution about two arcminutes. Pilot optics is composed an off-axis Gregorian type telescope and a refractive re-imager system. All optical elements, except the primary mirror, are in a cryostat cooled to 3K. We combined the optical, 3D dimensional measurement methods and thermo-elastic modeling to perform the optical alignment. The talk describes the system analysis, the alignment procedure, and finally the performances obtained during the first flight in September 2015.

  14. The Cost Implications of Less Tight Versus Tight Control of Hypertension in Pregnancy (CHIPS Trial)

    Science.gov (United States)

    Ahmed, Rashid J.; Gafni, Amiram; Hu, Zheng Jing; Pullenayegum, Eleanor; von Dadelszen, Peter; Rey, Evelyne; Ross, Susan; Asztalos, Elizabeth; Murphy, Kellie E.; Menzies, Jennifer; Sanchez, J. Johanna; Ganzevoort, Wessel; Helewa, Michael; Lee, Shoo K.; Lee, Terry; Logan, Alexander G.; Moutquin, Jean-Marie; Singer, Joel; Thornton, Jim G.; Welch, Ross; Magee, Laura A.

    2016-01-01

    The CHIPS randomized controlled trial (Control of Hypertension in Pregnancy Study) found no difference in the primary perinatal or secondary maternal outcomes between planned “less tight” (target diastolic 100 mm Hg) and “tight” (target diastolic 85 mm Hg) blood pressure management strategies among women with chronic or gestational hypertension. This study examined which of these management strategies is more or less costly from a third-party payer perspective. A total of 981 women with singleton pregnancies and nonsevere, nonproteinuric chronic or gestational hypertension were randomized at 14 to 33 weeks to less tight or tight control. Resources used were collected from 94 centers in 15 countries and costed as if the trial took place in each of 3 Canadian provinces as a cost-sensitivity analysis. Eleven hospital ward and 24 health service costs were obtained from a similar trial and provincial government health insurance schedules of medical benefits. The mean total cost per woman–infant dyad was higher in less tight versus tight control, but the difference in mean total cost (DM) was not statistically significant in any province: Ontario ($30 191.62 versus $24 469.06; DM $5723, 95% confidence interval, −$296 to $12 272; P=0.0725); British Columbia ($30 593.69 versus $24 776.51; DM $5817; 95% confidence interval, −$385 to $12 349; P=0.0725); or Alberta ($31 510.72 versus $25 510.49; DM $6000.23; 95% confidence interval, −$154 to $12 781; P=0.0637). Tight control may benefit women without increasing risk to neonates (as shown in the main CHIPS trial), without additional (and possibly lower) cost to the healthcare system. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01192412. PMID:27550914

  15. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G. Gomez and Y. Pakhotin

    2012-01-01

      A new track-based alignment for the DT chambers is ready for deployment: an offline tag has already been produced which will become part of the 52X Global Tag. This alignment was validated within the muon alignment group both at low and high momentum using a W/Z skim sample. It shows an improved mass resolution for pairs of stand-alone muons, improved curvature resolution at high momentum, and improved DT segment extrapolation residuals. The validation workflow for high-momentum muons used to depend solely on the “split cosmics” method, looking at the curvature difference between muon tracks reconstructed in the upper or lower half of CMS. The validation has now been extended to include energetic muons decaying from heavily boosted Zs: the di-muon invariant mass for global and stand-alone muons is reconstructed, and the invariant mass resolution is compared for different alignments. The main areas of development over the next few months will be preparing a new track-based C...

  16. Parameters for accurate genome alignment

    Directory of Open Access Journals (Sweden)

    Hamada Michiaki

    2010-02-01

    Full Text Available Abstract Background Genome sequence alignments form the basis of much research. Genome alignment depends on various mundane but critical choices, such as how to mask repeats and which score parameters to use. Surprisingly, there has been no large-scale assessment of these choices using real genomic data. Moreover, rigorous procedures to control the rate of spurious alignment have not been employed. Results We have assessed 495 combinations of score parameters for alignment of animal, plant, and fungal genomes. As our gold-standard of accuracy, we used genome alignments implied by multiple alignments of proteins and of structural RNAs. We found the HOXD scoring schemes underlying alignments in the UCSC genome database to be far from optimal, and suggest better parameters. Higher values of the X-drop parameter are not always better. E-values accurately indicate the rate of spurious alignment, but only if tandem repeats are masked in a non-standard way. Finally, we show that γ-centroid (probabilistic alignment can find highly reliable subsets of aligned bases. Conclusions These results enable more accurate genome alignment, with reliability measures for local alignments and for individual aligned bases. This study was made possible by our new software, LAST, which can align vertebrate genomes in a few hours http://last.cbrc.jp/.

  17. ABS: Sequence alignment by scanning

    KAUST Repository

    Bonny, Mohamed Talal

    2011-08-01

    Sequence alignment is an essential tool in almost any computational biology research. It processes large database sequences and considered to be high consumers of computation time. Heuristic algorithms are used to get approximate but fast results. We introduce fast alignment algorithm, called Alignment By Scanning (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the well-known alignment algorithms, the FASTA (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 76% enhancement in alignment score when it is compared with the FASTA Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  18. Fast global sequence alignment technique

    KAUST Repository

    Bonny, Mohamed Talal

    2011-11-01

    Bioinformatics database is growing exponentially in size. Processing these large amount of data may take hours of time even if super computers are used. One of the most important processing tool in Bioinformatics is sequence alignment. We introduce fast alignment algorithm, called \\'Alignment By Scanning\\' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the \\'GAP\\' (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 51% enhancement in alignment score when it is compared with the GAP Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  19. Discussions on the gas source of the Triassic Xujiahe Formation tight sandstone gas reservoirs in Yuanba and Tongnanba, Sichuan Basin:An answer to Yinfeng et al.%四川盆地元坝和通南巴地区须家河组致密砂岩气藏气源探讨--兼答印峰等

    Institute of Scientific and Technical Information of China (English)

    戴金星; 廖凤蓉; 倪云燕

    2013-01-01

    Gas-source correlation is generally focused on the genetic type of the main gas components, dominantly oil-associated gas or coal-derived gas. Gases from the Yuanba and Tongnanba gas reservoirs are dominated by methane with an average content of 95.36%. The average contents of ethane, propane, butane are 1.60%, 0.29%and 0.09%, respectively. In general, for the Yuanba and Tongnanba gas reservoirs, alkane gas has an average content of 97.34%, and CO2 has an average content of 0.63%, which only accounts for 6.5‰of the methane. According to the discrimination criteria thatδ13C2 value is greater than–28‰for coal-derived gas and lower than–28.5‰for the oil-associated gas, Yin et al. suggested that the gases from the Yuanba gas reservoir be a mixture of coal-derived and oil-associated gases, and the gases from the Tongnanba gas reservoir be oil-associated gas. However, the discrimination criteria of δ13C2 for coal-derived and oil-associated gases are only valid when the alkane gases have not undergone secondary alteration and have positive carbon isotopic series among C1-C4 alkanes. Hence, it is concluded that gases from the Yuanba and Tongnanba gas reservoirs are coal-derived gases due to their high content and heavy carbon isotopic values of methane (–31.3‰), which is typical for high mature coal-derived gases in the world. Though Yin et al. suggested that abiogenic CO2 of these two reservoirs is originated from metamorphism or hydrolysis of deep carbonate rocks, we proposed that these CO2 gases be self-generated and self-accumulated under the corrosion of calcarenaceous sandstone of the Triassic Xujiahe Formation.%  气藏的气源系指其中主要组分气的成因类型,通常为油型气或煤成气.元坝和通南巴气藏主要组分甲烷平均含量为95.36%,乙烷、丙烷和丁烷平均含量分别为1.60%、0.29%和0.09%,烷烃气总平均含量为97.34%,而 CO2平均含量仅0.63%,为甲烷的6.5‰.印峰等文中仅应用δ13

  20. MUSE alignment onto VLT

    Science.gov (United States)

    Laurent, Florence; Renault, Edgard; Boudon, Didier; Caillier, Patrick; Daguisé, Eric; Dupuy, Christophe; Jarno, Aurélien; Lizon, Jean-Louis; Migniau, Jean-Emmanuel; Nicklas, Harald; Piqueras, Laure

    2014-07-01

    MUSE (Multi Unit Spectroscopic Explorer) is a second generation Very Large Telescope (VLT) integral field spectrograph developed for the European Southern Observatory (ESO). It combines a 1' x 1' field of view sampled at 0.2 arcsec for its Wide Field Mode (WFM) and a 7.5"x7.5" field of view for its Narrow Field Mode (NFM). Both modes will operate with the improved spatial resolution provided by GALACSI (Ground Atmospheric Layer Adaptive Optics for Spectroscopic Imaging), that will use the VLT deformable secondary mirror and 4 Laser Guide Stars (LGS) foreseen in 2015. MUSE operates in the visible wavelength range (0.465-0.93 μm). A consortium of seven institutes is currently commissioning MUSE in the Very Large Telescope for the Preliminary Acceptance in Chile, scheduled for September, 2014. MUSE is composed of several subsystems which are under the responsibility of each institute. The Fore Optics derotates and anamorphoses the image at the focal plane. A Splitting and Relay Optics feed the 24 identical Integral Field Units (IFU), that are mounted within a large monolithic structure. Each IFU incorporates an image slicer, a fully refractive spectrograph with VPH-grating and a detector system connected to a global vacuum and cryogenic system. During 2012 and 2013, all MUSE subsystems were integrated, aligned and tested to the P.I. institute at Lyon. After successful PAE in September 2013, MUSE instrument was shipped to the Very Large Telescope in Chile where that was aligned and tested in ESO integration hall at Paranal. After, MUSE was directly transported, fully aligned and without any optomechanical dismounting, onto VLT telescope where the first light was overcame the 7th of February, 2014. This paper describes the alignment procedure of the whole MUSE instrument with respect to the Very Large Telescope (VLT). It describes how 6 tons could be move with accuracy better than 0.025mm and less than 0.25 arcmin in order to reach alignment requirements. The success

  1. Formatt: Correcting protein multiple structural alignments by incorporating sequence alignment

    Directory of Open Access Journals (Sweden)

    Daniels Noah M

    2012-10-01

    Full Text Available Abstract Background The quality of multiple protein structure alignments are usually computed and assessed based on geometric functions of the coordinates of the backbone atoms from the protein chains. These purely geometric methods do not utilize directly protein sequence similarity, and in fact, determining the proper way to incorporate sequence similarity measures into the construction and assessment of protein multiple structure alignments has proved surprisingly difficult. Results We present Formatt, a multiple structure alignment based on the Matt purely geometric multiple structure alignment program, that also takes into account sequence similarity when constructing alignments. We show that Formatt outperforms Matt and other popular structure alignment programs on the popular HOMSTRAD benchmark. For the SABMark twilight zone benchmark set that captures more remote homology, Formatt and Matt outperform other programs; depending on choice of embedded sequence aligner, Formatt produces either better sequence and structural alignments with a smaller core size than Matt, or similarly sized alignments with better sequence similarity, for a small cost in average RMSD. Conclusions Considering sequence information as well as purely geometric information seems to improve quality of multiple structure alignments, though defining what constitutes the best alignment when sequence and structural measures would suggest different alignments remains a difficult open question.

  2. Inflation by alignment

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, C.P. [PH -TH Division, CERN,CH-1211, Genève 23 (Switzerland); Department of Physics & Astronomy, McMaster University,1280 Main Street West, Hamilton ON (Canada); Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo ON (Canada); Roest, Diederik [Van Swinderen Institute for Particle Physics and Gravity, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands)

    2015-06-08

    Pseudo-Goldstone bosons (pGBs) can provide technically natural inflatons, as has been comparatively well-explored in the simplest axion examples. Although inflationary success requires trans-Planckian decay constants, f≳M{sub p}, several mechanisms have been proposed to obtain this, relying on (mis-)alignments between potential and kinetic energies in multiple-field models. We extend these mechanisms to a broader class of inflationary models, including in particular the exponential potentials that arise for pGB potentials based on noncompact groups (and so which might apply to moduli in an extra-dimensional setting). The resulting potentials provide natural large-field inflationary models and can predict a larger primordial tensor signal than is true for simpler single-field versions of these models. In so doing we provide a unified treatment of several alignment mechanisms, showing how each emerges as a limit of the more general setup.

  3. Wage Formation, Regional Migration and Local Labour Market Tightness

    OpenAIRE

    Carlsen, Fredrik; Johansen, Kåre; Røed, Knut

    2003-01-01

    Economic theory predicts that local labour market tightness affects local wage setting as well as individuals' migration decisions. But how should we measure local labour market tightness? In this paper we show that the common practice of using the local rate of unemployment as the tightness indicator may be misplaced. Instead, we propose a human capital adjusted outflow rate from unemployment that can be computed on the basis of micro register data. This outflow rate performs better than tra...

  4. Myelin architecture: zippering membranes tightly together.

    Science.gov (United States)

    Bakhti, Mostafa; Aggarwal, Shweta; Simons, Mikael

    2014-04-01

    Rapid nerve conduction requires the coating of axons by a tightly packed multilayered myelin membrane. In the central nervous system, myelin is formed from cellular processes that extend from oligodendrocytes and wrap in a spiral fashion around an axon, resulting in the close apposition of adjacent myelin membrane bilayers. In this review, we discuss the physical principles underlying the zippering of the plasma membrane of oligodendrocytes at the cytoplasmic and extracellular leaflet. We propose that the interaction of the myelin basic protein with the cytoplasmic leaflet of the myelin bilayer triggers its polymerization into a fibrous network that drives membrane zippering and protein extrusion. In contrast, the adhesion of the extracellular surfaces of myelin requires the down-regulation of repulsive components of the glycocalyx, in order to uncover weak and unspecific attractive forces that bring the extracellular surfaces into close contact. Unveiling the mechanisms of myelin membrane assembly at the cytoplasmic and extracelluar sites may help to understand how the myelin bilayers are disrupted and destabilized in the different demyelinating diseases.

  5. Orbit IMU alignment: Error analysis

    Science.gov (United States)

    Corson, R. W.

    1980-01-01

    A comprehensive accuracy analysis of orbit inertial measurement unit (IMU) alignments using the shuttle star trackers was completed and the results are presented. Monte Carlo techniques were used in a computer simulation of the IMU alignment hardware and software systems to: (1) determine the expected Space Transportation System 1 Flight (STS-1) manual mode IMU alignment accuracy; (2) investigate the accuracy of alignments in later shuttle flights when the automatic mode of star acquisition may be used; and (3) verify that an analytical model previously used for estimating the alignment error is a valid model. The analysis results do not differ significantly from expectations. The standard deviation in the IMU alignment error for STS-1 alignments was determined to the 68 arc seconds per axis. This corresponds to a 99.7% probability that the magnitude of the total alignment error is less than 258 arc seconds.

  6. Nuclear reactor alignment plate configuration

    Science.gov (United States)

    Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R

    2014-01-28

    An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.

  7. Alignment of concerns

    DEFF Research Database (Denmark)

    Andersen, Tariq Osman; Bansler, Jørgen P.; Kensing, Finn;

    E-health promises to enable and support active patient participation in chronic care. However, these fairly recent innovations are complicated matters and emphasize significant challenges, such as patients’ and clinicians’ different ways of conceptualizing disease and illness. Informed by insights...... from medical phenomenology and our own empirical work in telemonitoring and medical care of heart patients, we propose a design rationale for e-health systems conceptualized as the ‘alignment of concerns’....

  8. Alignment reference device

    Science.gov (United States)

    Patton, Gail Y.; Torgerson, Darrel D.

    1987-01-01

    An alignment reference device provides a collimated laser beam that minimizes angular deviations therein. A laser beam source outputs the beam into a single mode optical fiber. The output end of the optical fiber acts as a source of radiant energy and is positioned at the focal point of a lens system where the focal point is positioned within the lens. The output beam reflects off a mirror back to the lens that produces a collimated beam.

  9. Alignment as a Teacher Variable

    Science.gov (United States)

    Porter, Andrew C.; Smithson, John; Blank, Rolf; Zeidner, Timothy

    2007-01-01

    With the exception of the procedures developed by Porter and colleagues (Porter, 2002), other methods of defining and measuring alignment are essentially limited to alignment between tests and standards. Porter's procedures have been generalized to investigating the alignment between content standards, tests, textbooks, and even classroom…

  10. GPCODON ALIGNMENT: A GLOBAL PAIRWISE CODON BASED SEQUENCE ALIGNMENT APPROACH

    Directory of Open Access Journals (Sweden)

    Zeinab A. Fareed

    2016-02-01

    Full Text Available The alignment of two DNA sequences is a basic step in the analysis of biological data. Sequencing a long DNA sequence is one of the most interesting problems in bioinformatics. Several techniques have been developed to solve this sequence alignment problem like dynamic programming and heuristic algorithms. In this paper, we introduce (GPCodon alignment a pairwise DNA-DNA method for global sequence alignment that improves the accuracy of pairwise sequence alignment. We use a new scoring matrix to produce the final alignment called the empirical codon substitution matrix. Using this matrix in our technique enabled the discovery of new relationships between sequences that could not be discovered using traditional matrices. In addition, we present experimental results that show the performance of the proposed technique over eleven datasets of average length of 2967 bps. We compared the efficiency and accuracy of our techniques against a comparable tool called “Pairwise Align Codons” [1].

  11. Proposal for an alignment method of the CLIC linear accelerator - From geodesic networks to the active pre-alignment

    International Nuclear Information System (INIS)

    The compact linear collider (CLIC) is the particle accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nano-metric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved before. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required: 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active pre-alignment but shows the way to the last developments that have to be done for that purpose. A method is proposed. Based on the management of the Helmert transformations between Euclidean coordinate systems, from the geodetic networks to the metrological measurements, this method is likely to solve the CLIC pre-alignment problem. Large scale facilities have been built and Monte-Carlo simulations have been made in order to validate the mathematical modeling of the measurement systems and of the alignment references. When this is done, it will be possible to extrapolate the modeling to the entire CLIC length. It will be the last step towards the demonstration of the CLIC pre-alignment feasibility. (author)

  12. Diagnosing the tight building syndrome or diagnosing chemical hypersensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, S.A. (Northeast Center for Environmental Medicine, Syracuse, NY (USA))

    1989-01-01

    The abrupt exposure to urea foam formaldehyde insulation served as an alert to its spectrum of symptoms, including attacks of headache, flushing, laryngitis, dizziness, nausea, extreme weakness or exhaustion, arthralgia, an inability to concentrate, unwarranted depression, arrhythmia, or muscle spasms, and baffled physicians from many specialties. Later it was learned that toluene, xylene, benzene, natural gas, trichloroethylene, and many other chemicals were also capable of triggering chemical hypersensitivity. Other names for this condition include Environmentally Induced Illness (EI), the Tight Building Syndrome (TBS), the Sick Building Syndrome, and Building-Related Illness. The very symptoms patients complain of can be provoked within minutes and then subsequently alleviated with an intradermal injection of the appropriate strength of the triggering chemical. This technique aids in convincing the patient of the EI or TBS triggers so that the patient can begin to relate symptoms to environmental exposures and initiate measure to bring the disease under control. The key to safer buildings is increased ventilation, increased filtration of air, and decreased use of off-gassing synthetic materials.

  13. The CMS Muon System Alignment

    CERN Document Server

    Martinez Ruiz-Del-Arbol, P

    2009-01-01

    The alignment of the muon system of CMS is performed using different techniques: photogrammetry measurements, optical alignment and alignment with tracks. For track-based alignment, several methods are employed, ranging from a hit and impact point (HIP) algorithm and a procedure exploiting chamber overlaps to a global fit method based on the Millepede approach. For start-up alignment as long as available integrated luminosity is still significantly limiting the size of the muon sample from collisions, cosmic muon and beam halo signatures play a very strong role. During the last commissioning runs in 2008 the first aligned geometries have been produced and validated with data. The CMS offline computing infrastructure has been used in order to perform improved reconstructions. We present the computational aspects related to the calculation of alignment constants at the CERN Analysis Facility (CAF), the production and population of databases and the validation and performance in the official reconstruction. Also...

  14. Localization of Tight Closure in Two-Dimensional Rings

    Indian Academy of Sciences (India)

    Kamran Divaani-Aazar; Massoud Tousi

    2005-02-01

    It is shown that tight closure commutes with localization in any two-dimensional ring of prime characteristic if either is a Nagata ring or possesses a weak test element. Moreover, it is proved that tight closure commutes with localization at height one prime ideals in any ring of prime characteristic.

  15. Construction of Multivariate Tight Framelet Packets Associated with Dilation Matrix

    Institute of Scientific and Technical Information of China (English)

    Firdous A Shah; Abdullah

    2015-01-01

    In this paper, we present a method for constructing multivariate tight framelet packets associated with an arbitrary dilation matrix using unitary extension principles.We also prove how to construct various tight frames for L2(Rd) by replac-ing some mother framelets.

  16. Differences between tight and loose cultures : A 33-nation study

    NARCIS (Netherlands)

    Gelfand, M.J.; Raver, R.L.; Nishii, L.; Leslie, L.M.; Lun, J.; Lim, B.C.; Van de Vliert, E.

    2011-01-01

    With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multi

  17. CELT optics Alignment Procedure

    Science.gov (United States)

    Mast, Terry S.; Nelson, Jerry E.; Chanan, Gary A.; Noethe, Lothar

    2003-01-01

    The California Extremely Large Telescope (CELT) is a project to build a 30-meter diameter telescope for research in astronomy at visible and infrared wavelengths. The current optical design calls for a primary, secondary, and tertiary mirror with Ritchey-Chretién foci at two Nasmyth platforms. The primary mirror is a mosaic of 1080 actively-stabilized hexagonal segments. This paper summarizes a CELT report that describes a step-by-step procedure for aligning the many degrees of freedom of the CELT optics.

  18. Alignment of concerns

    DEFF Research Database (Denmark)

    Andersen, Tariq Osman; Bansler, Jørgen P.; Kensing, Finn;

    2014-01-01

    The emergence of patient-centered eHealth systems introduces new challenges, where patients come to play an increasingly important role. Realizing the promises requires an in-depth understanding of not only the technology, but also the needs of both clinicians and patients. However, insights from...... medical phenomenology bring forth how physicians and patients focus on different aspects of illness and that they often have starkly divergent concerns. This has important implications for the design of eHealth systems that seek to engage patients as active participants. We emphasize the crucial...... as a design rationale for successful eHealth, termed 'alignment of concerns'....

  19. Beam alignment system

    International Nuclear Information System (INIS)

    A patent is claimed for the invention of a beam alignment system. The aim of the invention is the obtention of an accurate monitoring of the beam position and direction. It is of great interest in the nuclear industry. The invention can be applied in an infrared laser beam for welding operations. An auxiliar radiation source is incorporated to the device. The system's configuration allows a simultaneous and separated utilisation of two beams. The description and the design of the proposed system are provided

  20. ATLAS Inner Detector Alignment

    CERN Document Server

    Bocci, A

    2008-01-01

    The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider at CERN. In order to achieve its physics goals, the ATLAS tracking requires that the positions of the silicon detector elements have to be known to a precision better than 10 μm. Several track-based alignment algorithms have been developed for the Inner Detector. An extensive validation has been performed with simulated events and real data coming from the ATLAS. Results from such validation are reported in this paper.

  1. TSGC and JSC Alignment

    Science.gov (United States)

    Sanchez, Humberto

    2013-01-01

    NASA and the SGCs are, by design, intended to work closely together and have synergistic Vision, Mission, and Goals. The TSGC affiliates and JSC have been working together, but not always in a concise, coordinated, nor strategic manner. Today we have a couple of simple ideas to present about how TSGC and JSC have started to work together in a more concise, coordinated, and strategic manner, and how JSC and non-TSG Jurisdiction members have started to collaborate: Idea I: TSGC and JSC Technical Alignment Idea II: Concept of Clusters.

  2. High accuracy alignment facility for the receiver and transmitter of the BepiColombo Laser Altimeter.

    Science.gov (United States)

    Chakraborty, Sumita; Affolter, Michael; Gunderson, Kurt; Neubert, Jakob; Thomas, Nicolas; Beck, Thomas; Gerber, Michael; Graf, Stefan; Piazza, Daniele; Pommerol, Antoine; Roethlisberger, Guillaume; Seiferlin, Karsten

    2012-07-10

    The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group. We list the different steps of the calibration of the alignment facility and estimate the errors made at each of these steps. We finally prove that the current facility is ready for the alignment of the flight instrument. Its angular accuracy is 23 μrad. PMID:22781273

  3. A two scale analysis of tight sandstones

    Science.gov (United States)

    Adler, P. M.; Davy, C. A.; Song, Y.; Troadec, D.; Hauss, G.; Skoczylas, F.

    2015-12-01

    Tight sandstones have a low porosity and a very small permeability K. Available models for K do not compare well with measurements. These sandstones are made of SiO_2 grains, with a typical size of several hundreds of micron. These grains are separated by a network of micro-cracks, with sizes ranging between microns down to tens of nm. Therefore, the structure can be schematized by Voronoi polyhedra separated by plane and permeable polygonal micro-cracks. Our goal is to estimate K based on a two scale analysis and to compare the results to measurements. For a particular sample [2], local measurements on several scales include FIB/SEM [3], CMT and 2D SEM. FIB/SEM is selected because the peak pore size given by Mercury Intrusion Porosimetry is of 350nm. FIB/SEM imaging (with 50 nm voxel size) identifies an individual crack of 180nm average opening, whereas CMT provides a connected porosity (individual crack) for 60 nm voxel size, of 4 micron average opening. Numerical modelling is performed by combining the micro-crack network scale (given by 2D SEM) and the 3D micro-crack scale (given by either FIB/SEM or CMT). Estimates of the micro-crack density are derived from 2D SEM trace maps by counting the intersections with scanlines, the surface density of traces, and the number of fracture intersections. K is deduced by using a semi empirical formula valid for identical, isotropic and uniformly distributed fractures [1]. This value is proportional to the micro-crack transmissivity sigma. Sigma is determined by solving the Stokes equation in the micro-cracks measured by FIB/SEM or CMT. K is obtained by combining the two previous results. Good correlation with measured values on centimetric plugs is found when using sigma from CMT data. The results are discussed and further research is proposed. [1] Adler et al, Fractured porous media, Oxford Univ. Press, 2012. [2] Duan et al, Int. J. Rock Mech. Mining Sci., 65, p75, 2014. [3] Song et al, Marine and Petroleum Eng., 65, p63

  4. Computing alignment plots efficiently

    CERN Document Server

    Krusche, Peter

    2009-01-01

    Dot plots are a standard method for local comparison of biological sequences. In a dot plot, a substring to substring distance is computed for all pairs of fixed-size windows in the input strings. Commonly, the Hamming distance is used since it can be computed in linear time. However, the Hamming distance is a rather crude measure of string similarity, and using an alignment-based edit distance can greatly improve the sensitivity of the dot plot method. In this paper, we show how to compute alignment plots of the latter type efficiently. Given two strings of length m and n and a window size w, this problem consists in computing the edit distance between all pairs of substrings of length w, one from each input string. The problem can be solved by repeated application of the standard dynamic programming algorithm in time O(mnw^2). This paper gives an improved data-parallel algorithm, running in time $O(mnw/\\gamma/p)$ using vector operations that work on $\\gamma$ values in parallel and $p$ processors. We show ex...

  5. All about alignment

    CERN Multimedia

    2006-01-01

    The ALICE absorbers, iron wall and superstructure have been installed with great precision. The ALICE front absorber, positioned in the centre of the detector, has been installed and aligned. Weighing more than 400 tonnes, the ALICE absorbers and the surrounding support structures have been installed and aligned with a precision of 1-2 mm, hardly an easy task but a very important one. The ALICE absorbers are made of three parts: the front absorber, a 35-tonne cone-shaped structure, and two small-angle absorbers, long straight cylinder sections weighing 18 and 40 tonnes. The three pieces lined up have a total length of about 17 m. In addition to these, ALICE technicians have installed a 300-tonne iron filter wall made of blocks that fit together like large Lego pieces and a surrounding metal support structure to hold the tracking and trigger chambers. The absorbers house the vacuum chamber and are also the reference surface for the positioning of the tracking and trigger chambers. For this reason, the ab...

  6. Conditional alignment random fields for multiple motion sequence alignment.

    Science.gov (United States)

    Kim, Minyoung

    2013-11-01

    We consider the multiple time-series alignment problem, typically focusing on the task of synchronizing multiple motion videos of the same kind of human activity. Finding an optimal global alignment of multiple sequences is infeasible, while there have been several approximate solutions, including iterative pairwise warping algorithms and variants of hidden Markov models. In this paper, we propose a novel probabilistic model that represents the conditional densities of the latent target sequences which are aligned with the given observed sequences through the hidden alignment variables. By imposing certain constraints on the target sequences at the learning stage, we have a sensible model for multiple alignments that can be learned very efficiently by the EM algorithm. Compared to existing methods, our approach yields more accurate alignment while being more robust to local optima and initial configurations. We demonstrate its efficacy on both synthetic and real-world motion videos including facial emotions and human activities. PMID:24051737

  7. Overcoming low-alignment signal contrast induced alignment failure by alignment signal enhancement

    Science.gov (United States)

    Lee, Byeong Soo; Kim, Young Ha; Hwang, Hyunwoo; Lee, Jeongjin; Kong, Jeong Heung; Kang, Young Seog; Paarhuis, Bart; Kok, Haico; de Graaf, Roelof; Weichselbaum, Stefan; Droste, Richard; Mason, Christopher; Aarts, Igor; de Boeij, Wim P.

    2016-03-01

    Overlay is one of the key factors which enables optical lithography extension to 1X node DRAM manufacturing. It is natural that accurate wafer alignment is a prerequisite for good device overlay. However, alignment failures or misalignments are commonly observed in a fab. There are many factors which could induce alignment problems. Low alignment signal contrast is one of the main issues. Alignment signal contrast can be degraded by opaque stack materials or by alignment mark degradation due to processes like CMP. This issue can be compounded by mark sub-segmentation from design rules in combination with double or quadruple spacer process. Alignment signal contrast can be improved by applying new material or process optimization, which sometimes lead to the addition of another process-step with higher costs. If we can amplify the signal components containing the position information and reduce other unwanted signal and background contributions then we can improve alignment performance without process change. In this paper we use ASML's new alignment sensor (as was introduced and released on the NXT:1980Di) and sample wafers with special stacks which can induce poor alignment signal to demonstrate alignment and overlay improvement.

  8. Pareto optimal pairwise sequence alignment.

    Science.gov (United States)

    DeRonne, Kevin W; Karypis, George

    2013-01-01

    Sequence alignment using evolutionary profiles is a commonly employed tool when investigating a protein. Many profile-profile scoring functions have been developed for use in such alignments, but there has not yet been a comprehensive study of Pareto optimal pairwise alignments for combining multiple such functions. We show that the problem of generating Pareto optimal pairwise alignments has an optimal substructure property, and develop an efficient algorithm for generating Pareto optimal frontiers of pairwise alignments. All possible sets of two, three, and four profile scoring functions are used from a pool of 11 functions and applied to 588 pairs of proteins in the ce_ref data set. The performance of the best objective combinations on ce_ref is also evaluated on an independent set of 913 protein pairs extracted from the BAliBASE RV11 data set. Our dynamic-programming-based heuristic approach produces approximated Pareto optimal frontiers of pairwise alignments that contain comparable alignments to those on the exact frontier, but on average in less than 1/58th the time in the case of four objectives. Our results show that the Pareto frontiers contain alignments whose quality is better than the alignments obtained by single objectives. However, the task of identifying a single high-quality alignment among those in the Pareto frontier remains challenging.

  9. ALIGNMENT OF SUPERMASSIVE BLACK HOLE BINARY ORBITS AND SPINS

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M. Coleman [Department of Astronomy and Joint Space-Science Institute, University of Maryland, College Park, MD 20742-2421 (United States); Krolik, Julian H., E-mail: miller@astro.umd.edu [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)

    2013-09-01

    Recent studies of accretion onto supermassive black hole binaries suggest that much, perhaps most, of the matter eventually accretes onto one hole or the other. If so, then for binaries whose inspiral from {approx}1 pc to {approx}10{sup -3}-10{sup -2} pc is driven by interaction with external gas, both the binary orbital axis and the individual black hole spins can be reoriented by angular momentum exchange with this gas. Here we show that, unless the binary mass ratio is far from unity, the spins of the individual holes align with the binary orbital axis in a time {approx}few-100 times shorter than the binary orbital axis aligns with the angular momentum direction of the incoming circumbinary gas; the spin of the secondary aligns more rapidly than that of the primary by a factor {approx}(m{sub 1}/m{sub 2}){sup 1/2} > 1. Thus the binary acts as a stabilizing agent, so that for gas-driven systems, the black hole spins are highly likely to be aligned (or counteraligned if retrograde accretion is common) with each other and with the binary orbital axis. This alignment can significantly reduce the recoil speed resulting from subsequent black hole merger.

  10. Onorbit IMU alignment error budget

    Science.gov (United States)

    Corson, R. W.

    1980-01-01

    The Star Tracker, Crew Optical Alignment Sight (COAS), and Inertial Measurement Unit (IMU) from a complex navigation system with a multitude of error sources were combined. A complete list of the system errors is presented. The errors were combined in a rational way to yield an estimate of the IMU alignment accuracy for STS-1. The expected standard deviation in the IMU alignment error for STS-1 type alignments was determined to be 72 arc seconds per axis for star tracker alignments and 188 arc seconds per axis for COAS alignments. These estimates are based on current knowledge of the star tracker, COAS, IMU, and navigation base error specifications, and were partially verified by preliminary Monte Carlo analysis.

  11. Dust alignment in astrophysical environments

    Science.gov (United States)

    Lazarian, Alex; Thiem Hoang, Chi

    Dust is known to be aligned in interstellar medium and the arising polarization is extensively used to trace magnetic fields. What process aligns dust grains was one of the most long-standing problems of astrophysics in spite of the persistent efforts to solve it. For years the Davis-Greenstein paramagnetic alignment was the primary candidate for explaining grain alignment. However, the situation is different now and the most promising mechanism is associated with radiative torques (RATs) acting on irregular grains. I shall present the analytical theory of RAT alignment, discuss the observational tests that support this theory. I shall also discuss in what situations we expect to see the dominance of paramagnetic alignment.

  12. Nuclear reactor internals alignment configuration

    Science.gov (United States)

    Gilmore, Charles B.; Singleton, Norman R.

    2009-11-10

    An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

  13. On aligning trees

    CERN Document Server

    Calder, J

    1997-01-01

    The increasing availability of corpora annotated for linguistic structure prompts the question: if we have the same texts, annotated for phrase structure under two different schemes, to what extent do the annotations agree on structuring within the text? We suggest the term tree alignment to indicate the situation where two markup schemes choose to bracket off the same text elements. We propose a general method for determining agreement between two analyses. We then describe an efficient implementation, which is also modular in that the core of the implementation can be reused regardless of the format of markup used in the corpora. The output of the implementation on the Susanne and Penn treebank corpora is discussed.

  14. The alignment strategy of HADES

    Energy Technology Data Exchange (ETDEWEB)

    Pechenova, O., E-mail: O.Pechenova@gsi.de [Institut für Kernphysik, Johann Wolfgang Goethe-Universität, 60438 Frankfurt (Germany); Pechenov, V. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Galatyuk, T. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Technische Universität Darmstadt, D-64289 Darmstadt (Germany); Hennino, T. [Institut de Physique Nucléaire (UMR 8608), CNRS/IN2P3 – Université Paris Sud, F-91406 Orsay Cedex (France); Holzmann, R. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Kornakov, G. [Departamento de Física de Partículas, Univ. de Santiago de Compostela, 15706 Santiago de Compostela (Spain); Technische Universität Darmstadt, D-64289 Darmstadt (Germany); Markert, J.; Müntz, C. [Institut für Kernphysik, Johann Wolfgang Goethe-Universität, 60438 Frankfurt (Germany); Salabura, P. [Smoluchowski Institute of Physics, Jagiellonian University of Kraków, 30-059 Kraków (Poland); Schmah, A. [Lawrence Berkeley National Laboratory, Berkeley (United States); Schwab, E. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Stroth, J. [Institut für Kernphysik, Johann Wolfgang Goethe-Universität, 60438 Frankfurt (Germany); GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany)

    2015-06-11

    The global as well as intrinsic alignment of any spectrometer impacts directly on its performance and the quality of the achievable physics results. An overview of the current alignment procedure of the DiElectron Spectrometer HADES is presented with an emphasis on its main features and its accuracy. The sequence of all steps and procedures is given, including details on photogrammetric and track-based alignment.

  15. GraphAlignment: Bayesian pairwise alignment of biological networks

    Directory of Open Access Journals (Sweden)

    Kolář Michal

    2012-11-01

    Full Text Available Abstract Background With increased experimental availability and accuracy of bio-molecular networks, tools for their comparative and evolutionary analysis are needed. A key component for such studies is the alignment of networks. Results We introduce the Bioconductor package GraphAlignment for pairwise alignment of bio-molecular networks. The alignment incorporates information both from network vertices and network edges and is based on an explicit evolutionary model, allowing inference of all scoring parameters directly from empirical data. We compare the performance of our algorithm to an alternative algorithm, Græmlin 2.0. On simulated data, GraphAlignment outperforms Græmlin 2.0 in several benchmarks except for computational complexity. When there is little or no noise in the data, GraphAlignment is slower than Græmlin 2.0. It is faster than Græmlin 2.0 when processing noisy data containing spurious vertex associations. Its typical case complexity grows approximately as O(N2.6. On empirical bacterial protein-protein interaction networks (PIN and gene co-expression networks, GraphAlignment outperforms Græmlin 2.0 with respect to coverage and specificity, albeit by a small margin. On large eukaryotic PIN, Græmlin 2.0 outperforms GraphAlignment. Conclusions The GraphAlignment algorithm is robust to spurious vertex associations, correctly resolves paralogs, and shows very good performance in identification of homologous vertices defined by high vertex and/or interaction similarity. The simplicity and generality of GraphAlignment edge scoring makes the algorithm an appropriate choice for global alignment of networks.

  16. Three-dimensional measurement of a tightly focused laser beam

    Directory of Open Access Journals (Sweden)

    Xiangsheng Xie

    2013-02-01

    Full Text Available The spatial structure of a tightly focused light field is measured with a double knife-edge scanning method. The measurement method is based on the use of a high-quality double knife-edge fabricated from a right-angled silicon fragment mounted on a photodetector. The reconstruction of the three-dimensional structures of tightly focused spots is carried out with both uniform and partially obstructed linearly polarized incident light beams. The optical field distribution is found to deviate substantially from the input beam profile in the tightly focused region, which is in good agreement with the results of numerical simulations.

  17. Pyro-Align: Sample-Align based Multiple Alignment system for Pyrosequencing Reads of Large Number

    CERN Document Server

    Saeed, Fahad

    2009-01-01

    Pyro-Align is a multiple alignment program specifically designed for pyrosequencing reads of huge number. Multiple sequence alignment is shown to be NP-hard and heuristics are designed for approximate solutions. Multiple sequence alignment of pyrosequenceing reads is complex mainly because of 2 factors. One being the huge number of reads, making the use of traditional heuristics,that scale very poorly for large number, unsuitable. The second reason is that the alignment cannot be performed arbitrarily, because the position of the reads with respect to the original genome is important and has to be taken into account.In this report we present a short description of the multiple alignment system for pyrosequencing reads.

  18. Diagenesis and porosity evolution of tight sand reservoirs in Carboniferous Benxi Formation, Southeast Ordos Basin

    Science.gov (United States)

    Hu, Peng; Yu, Xinghe; Shan, Xin; Su, Dongxu; Wang, Jiao; Li, Yalong; Shi, Xin; Xu, Liqiang

    2016-04-01

    The Ordos Basin, situated in west-central China, is one of the oldest and most important fossil-fuel energy base, which contains large reserves of coal, oil and natural gas. The Upper Palaeozoic strata are widely distributed with rich gas-bearing and large natural gas resources, whose potential is tremendous. Recent years have witnessed a great tight gas exploration improvement of the Upper Paleozoic in Southeastern Ordos basin. The Carboniferous Benxi Formation, mainly buried more than 2,500m, is the key target strata for hydrocarbon exploration, which was deposited in a barrier island and tidal flat environment. The sandy bars and flats are the favorable sedimentary microfacies. With an integrated approach of thin-section petrophysics, constant velocity mercury injection test, scanning electron microscopy and X-ray diffractometry, diagenesis and porosity evolution of tight sand reservoirs of Benxi Formation were analyzed in detail. The result shows that the main lithology of sandstone in this area is dominated by moderately to well sorted quartz sandstone. The average porosity and permeability is 4.72% and 1.22mD. The reservoirs of Benxi Formation holds a variety of pore types and the pore throats, with obvious heterogeneity and poor connection. Based on the capillary pressure curve morphological characteristics and parameters, combined with thin section and phycical property data, the reservoir pore structure of Benxi Formation can be divided into 4 types, including mid pore mid throat type(I), mid pore fine throat type(II), small pore fine throat type(III) and micro pro micro throat type(Ⅳ). The reservoirs primarily fall in B-subsate of middle diagenesis and late diagenesis, which mainly undergo compaction, cmentation, dissolution and fracturing process. Employing the empirical formula of different sorting for unconsolideated sandstone porosity, the initial sandstone porosity is 38.32% on average. Quantitative evaluation of the increase and decrease of

  19. Tight Planar Contact Manifolds with Vanishing Heegaard Floer Contact Invariants

    OpenAIRE

    Conway, James; Kaloti, Amey; Kulkarni, Dheeraj

    2014-01-01

    In this note, we exhibit infinite families of tight non-fillable contact manifolds supported by planar open books with vanishing Heegaard Floer contact invariants. Moreover, we also exhibit an infinite such family where the supported manifold is hyperbolic.

  20. Effect of a tight necktie on intraocular pressure

    OpenAIRE

    Božić Marija; Hentova-Senćanin Paraskeva; Branković Aleksandra; Marjanović Ivan; Jocić Đorđević Jasmina; Senćanin Ivan

    2012-01-01

    Introduction. Any factor causing constriction of the neck may lead to an increase in intraocular pressure. A tight necktie may result in increasing intraocular pressure, which could lead to an erroneous diagnosis and treatment of ocular hypertension or even glaucoma. This study was aimed at evaluating the effect of a tight necktie on intraocular pressure measurement using Goldmann applanation tonometry. Material and Methods. This study included forty eyes of 20 patients with primary ope...

  1. Fracking in Tight Shales: What Is It, What Does It Accomplish, and What Are Its Consequences?

    Science.gov (United States)

    Norris, J. Quinn; Turcotte, Donald L.; Moores, Eldridge M.; Brodsky, Emily E.; Rundle, John B.

    2016-06-01

    Fracking is a popular term referring to hydraulic fracturing when it is used to extract hydrocarbons. We distinguish between low-volume traditional fracking and the high-volume modern fracking used to recover large volumes of hydrocarbons from shales. Shales are fine-grained rocks with low granular permeabilities. During the formation of oil and gas, large fluid pressures are generated. These pressures result in natural fracking, and the resulting fracture permeability allows oil and gas to escape, reducing the fluid pressures. These fractures may subsequently be sealed by mineral deposition, resulting in tight shale formations. The objective of modern fracking is to reopen these fractures and/or create new fractures on a wide range of scales. Modern fracking has had a major impact on the availability of oil and gas globally; however, there are serious environmental objections to modern fracking, which should be weighed carefully against its benefits.

  2. Tightness-looseness across the 50 united states.

    Science.gov (United States)

    Harrington, Jesse R; Gelfand, Michele J

    2014-06-01

    This research demonstrates wide variation in tightness-looseness (the strength of punishment and degree of latitude/permissiveness) at the state level in the United States, as well as its association with a variety of ecological and historical factors, psychological characteristics, and state-level outcomes. Consistent with theory and past research, ecological and man-made threats--such as a higher incidence of natural disasters, greater disease prevalence, fewer natural resources, and greater degree of external threat--predicted increased tightness at the state level. Tightness is also associated with higher trait conscientiousness and lower trait openness, as well as a wide array of outcomes at the state level. Compared with loose states, tight states have higher levels of social stability, including lowered drug and alcohol use, lower rates of homelessness, and lower social disorganization. However, tight states also have higher incarceration rates, greater discrimination and inequality, lower creativity, and lower happiness relative to loose states. In all, tightness-looseness provides a parsimonious explanation of the wide variation we see across the 50 states of the United States of America.

  3. Tightness-looseness across the 50 united states.

    Science.gov (United States)

    Harrington, Jesse R; Gelfand, Michele J

    2014-06-01

    This research demonstrates wide variation in tightness-looseness (the strength of punishment and degree of latitude/permissiveness) at the state level in the United States, as well as its association with a variety of ecological and historical factors, psychological characteristics, and state-level outcomes. Consistent with theory and past research, ecological and man-made threats--such as a higher incidence of natural disasters, greater disease prevalence, fewer natural resources, and greater degree of external threat--predicted increased tightness at the state level. Tightness is also associated with higher trait conscientiousness and lower trait openness, as well as a wide array of outcomes at the state level. Compared with loose states, tight states have higher levels of social stability, including lowered drug and alcohol use, lower rates of homelessness, and lower social disorganization. However, tight states also have higher incarceration rates, greater discrimination and inequality, lower creativity, and lower happiness relative to loose states. In all, tightness-looseness provides a parsimonious explanation of the wide variation we see across the 50 states of the United States of America. PMID:24843116

  4. Key Elements Controlling Oil Accumulation within the Tight Sandstones

    Institute of Scientific and Technical Information of China (English)

    Haiyan Hu; Zhiping Zeng; Jianzhang Liu

    2015-01-01

    Tight oil sandstone reservoirs with low porosity and permeability, which are an uncon-ventional petroleum resource, have been discovered in the Jurassic intervals of the central Junggar Ba-sin, the northwestern China. To reveal the accumulation mechanism, a relatively comprehensive re-search was conducted, including oil-source correlation, porosity evolution, and hydrocarbon charging history. The results show that crude oil of these tight sandstone reservoirs were mainly from Permian source rocks with some contribution from Jurassic source rocks. The reservoirs were buried at shallow depth (5%). In contrast, the sandstone reservoir had already become tight and did not provide available space to ac-cumulate oil due to severe compaction and cementation when hydrocarbon from Jurassic source rock filled, evidenced by low GOI values (<5%). Therefore, reservoir porosity controls the oil accumulation within tight sandstone. Whether tight sandstone reservoirs accumulate oil depends on the reservoir quality when hydrocarbons charge. Before the exploration of tight oil sandstone reservoirs, it should be required to investigate the relationship between oil charging history and porosity evolution to reduce the exploration risk and figure out the available targets.

  5. Vacuum Alignment with more Flavors

    DEFF Research Database (Denmark)

    Ryttov, Thomas

    2014-01-01

    We study the alignment of the vacuum in gauge theories with $N_f$ Dirac fermions transforming according to a complex representation of the gauge group. The alignment of the vacuum is produced by adding a small mass perturbation to the theory. We study in detail the $N_f=2,3$ and $4$ case. For $N...

  6. CATO: The Clone Alignment Tool.

    Directory of Open Access Journals (Sweden)

    Peter V Henstock

    Full Text Available High-throughput cloning efforts produce large numbers of sequences that need to be aligned, edited, compared with reference sequences, and organized as files and selected clones. Different pieces of software are typically required to perform each of these tasks. We have designed a single piece of software, CATO, the Clone Alignment Tool, that allows a user to align, evaluate, edit, and select clone sequences based on comparisons to reference sequences. The input and output are designed to be compatible with standard data formats, and thus suitable for integration into a clone processing pipeline. CATO provides both sequence alignment and visualizations to facilitate the analysis of cloning experiments. The alignment algorithm matches each of the relevant candidate sequences against each reference sequence. The visualization portion displays three levels of matching: 1 a top-level summary of the top candidate sequences aligned to each reference sequence, 2 a focused alignment view with the nucleotides of matched sequences displayed against one reference sequence, and 3 a pair-wise alignment of a single reference and candidate sequence pair. Users can select the minimum matching criteria for valid clones, edit or swap reference sequences, and export the results to a summary file as part of the high-throughput cloning workflow.

  7. Lexical alignment in triadic communication

    Directory of Open Access Journals (Sweden)

    Anouschka eFoltz

    2015-02-01

    Full Text Available Lexical alignment refers to the adoption of one’s interlocutor’s lexical items. Accounts of the mechanisms underlying such lexical alignment differ (among other aspects in the role assigned to addressee-centered behavior. In this study, we used a triadic communicative situation to test which factors may modulate the extent to which participants’ lexical alignment reflects addressee-centered behavior. Pairs of naïve participants played a picture matching game and received information about the order in which pictures were to be matched from a voice over headphones. On critical trials, participants did or did not hear a name for the picture to be matched next over headphones. Importantly, when the voice over headphones provided a name, it did not match the name that the interlocutor had previously used to describe the object. Participants overwhelmingly used the word that the voice over headphones provided. This result points to non-addressee-centered behavior and is discussed in terms of disrupting alignment with the interlocutor as well as in terms of establishing alignment with the voice over headphones. In addition, the type of picture (line drawing vs. tangram shape independently modulated lexical alignment, such that participants showed more lexical alignment to their interlocutor for (more ambiguous tangram shapes compared to line drawings. Overall, the results point to a rather large role for non-addressee-centered behavior during lexical alignment.

  8. Alignment of flexible protein structures.

    Science.gov (United States)

    Shatsky, M; Fligelman, Z Y; Nussinov, R; Wolfson, H J

    2000-01-01

    We present two algorithms which align flexible protein structures. Both apply efficient structural pattern detection and graph theoretic techniques. The FlexProt algorithm simultaneously detects the hinge regions and aligns the rigid subparts of the molecules. It does it by efficiently detecting maximal congruent rigid fragments in both molecules and calculating their optimal arrangement which does not violate the protein sequence order. The FlexMol algorithm is sequence order independent, yet requires as input the hypothesized hinge positions. Due its sequence order independence it can also be applied to protein-protein interface matching and drug molecule alignment. It aligns the rigid parts of the molecule using the Geometric Hashing method and calculates optimal connectivity among these parts by graph-theoretic techniques. Both algorithms are highly efficient even compared with rigid structure alignment algorithms. Typical running times on a standard desktop PC (400 MHz) are about 7 seconds for FlexProt and about 1 minute for FlexMol.

  9. Alignments in the nobelium isotopes

    Institute of Scientific and Technical Information of China (English)

    ZHENG Shi-Zie; XU Fu-Rong; YUAN Cen-Xi; QI Chong

    2009-01-01

    Total-Routhian-Surface calculations have been performed to investigate the deformation and align-ment properties of the No isotopes. It is found that normal deformed and superdeformed states in these nuclei can coexist at low excitation energies. In neutron-deficient No isotopes, the superdeformed shapes can even become the ground states. Moreover, we plotted the kinematic moments of inertia of the No isotopes, which follow very nicely available experimental data. It is noted that, as the rotational frequency increases, align-ments develop at hω=0.2-0.3 MeV. Our calculations show that the occupation of the vj orbital plays an important role in the alignments of the No isotopes.

  10. The CMS Silicon Tracker Alignment

    CERN Document Server

    Castello, R

    2008-01-01

    The alignment of the Strip and Pixel Tracker of the Compact Muon Solenoid experiment, with its large number of independent silicon sensors and its excellent spatial resolution, is a complex and challenging task. Besides high precision mounting, survey measurements and the Laser Alignment System, track-based alignment is needed to reach the envisaged precision.\\\\ Three different algorithms for track-based alignment were successfully tested on a sample of cosmic-ray data collected at the Tracker Integration Facility, where 15\\% of the Tracker was tested. These results, together with those coming from the CMS global run, will provide the basis for the full-scale alignment of the Tracker, which will be carried out with the first \\emph{p-p} collisions.

  11. Space Mirror Alignment System

    Science.gov (United States)

    Jau, Bruno M.; McKinney, Colin; Smythe, Robert F.; Palmer, Dean L.

    2011-01-01

    An optical alignment mirror mechanism (AMM) has been developed with angular positioning accuracy of +/-0.2 arcsec. This requires the mirror s linear positioning actuators to have positioning resolutions of +/-112 nm to enable the mirror to meet the angular tip/tilt accuracy requirement. Demonstrated capabilities are 0.1 arc-sec angular mirror positioning accuracy, which translates into linear positioning resolutions at the actuator of 50 nm. The mechanism consists of a structure with sets of cross-directional flexures that enable the mirror s tip and tilt motion, a mirror with its kinematic mount, and two linear actuators. An actuator comprises a brushless DC motor, a linear ball screw, and a piezoelectric brake that holds the mirror s position while the unit is unpowered. An interferometric linear position sensor senses the actuator s position. The AMMs were developed for an Astrometric Beam Combiner (ABC) optical bench, which is part of an interferometer development. Custom electronics were also developed to accommodate the presence of multiple AMMs within the ABC and provide a compact, all-in-one solution to power and control the AMMs.

  12. Magnetic alignment and the Poisson alignment reference system

    Science.gov (United States)

    Griffith, L. V.; Schenz, R. F.; Sommargren, G. E.

    1990-08-01

    Three distinct metrological operations are necessary to align a free-electron laser (FEL): the magnetic axis must be located, a straight line reference (SLR) must be generated, and the magnetic axis must be related to the SLR. This article begins with a review of the motivation for developing an alignment system that will assure better than 100-μm accuracy in the alignment of the magnetic axis throughout an FEL. The 100-μm accuracy is an error circle about an ideal axis for 300 m or more. The article describes techniques for identifying the magnetic axes of solenoids, quadrupoles, and wiggler poles. Propagation of a laser beam is described to the extent of revealing sources of nonlinearity in the beam. Development of a straight-line reference based on the Poisson line, a diffraction effect, is described in detail. Spheres in a large-diameter laser beam create Poisson lines and thus provide a necessary mechanism for gauging between the magnetic axis and the SLR. Procedures for installing FEL components and calibrating alignment fiducials to the magnetic axes of the components are also described. The Poisson alignment reference system should be accurate to 25 μm over 300 m, which is believed to be a factor-of-4 improvement over earlier techniques. An error budget shows that only 25% of the total budgeted tolerance is used for the alignment reference system, so the remaining tolerances should fall within the allowable range for FEL alignment.

  13. 30 kV coaxial vacuum-tight feedthrough for operation at cryogenic temperatures

    CERN Document Server

    Kreslo, I; Delaquis, S; Ereditato, A; Janos, S; Messina, M; Moser, U; Rossi, B; Zeller, M

    2010-01-01

    In this paper we describe the technology of building a vacuum-tight high voltage feedthrough which is able to operate at voltages up to 30 kV. The feedthrough has a coaxial structure with a grounded sheath which makes it capable to lead high voltage potentials into cryogenic liquids, without risk of surface discharges in the gas phase above the liquid level. The feedthrough is designed to be used in ionization detectors, based on liquefied noble gases, such as Argon or Xenon.

  14. Alignment of supermassive black hole binary orbits and spins

    CERN Document Server

    Miller, M Coleman

    2013-01-01

    Recent studies of accretion onto supermassive black hole binaries suggest that much, perhaps most, of the matter eventually accretes onto one hole or the other. If so, then for binaries whose inspiral from ~1 pc to 0.001 - 0.01 pc is driven by interaction with external gas, both the binary orbital axis and the individual black hole spins can be reoriented by angular momentum exchange with this gas. Here we show that, unless the binary mass ratio is far from unity, the spins of the individual holes align with the binary orbital axis in a time few-100 times shorter than the binary orbital axis aligns with the angular momentum direction of the incoming circumbinary gas; the spin of the secondary aligns more rapidly than that of the primary by a factor ~(m_1/m_2)^{1/2}>1. Thus the binary acts as a stabilizing agent, so that for gas-driven systems, the black hole spins are highly likely to be aligned (or counteraligned if retrograde accretion is common) with each other and with the binary orbital axis. This alignm...

  15. Aligning for Innovation - Alignment Strategy to Drive Innovation

    Science.gov (United States)

    Johnson, Hurel; Teltschik, David; Bussey, Horace, Jr.; Moy, James

    2010-01-01

    With the sudden need for innovation that will help the country achieve its long-term space exploration objectives, the question of whether NASA is aligned effectively to drive the innovation that it so desperately needs to take space exploration to the next level should be entertained. Authors such as Robert Kaplan and David North have noted that companies that use a formal system for implementing strategy consistently outperform their peers. They have outlined a six-stage management systems model for implementing strategy, which includes the aligning of the organization towards its objectives. This involves the alignment of the organization from the top down. This presentation will explore the impacts of existing U.S. industrial policy on technological innovation; assess the current NASA organizational alignment and its impacts on driving technological innovation; and finally suggest an alternative approach that may drive the innovation needed to take the world to the next level of space exploration, with NASA truly leading the way.

  16. The media of sociology: tight or loose translations?

    Science.gov (United States)

    Guggenheim, Michael

    2015-06-01

    Sociologists have increasingly come to recognize that the discipline has unduly privileged textual representations, but efforts to incorporate visual and other media are still only in their beginning. This paper develops an analysis of the ways objects of knowledge are translated into other media, in order to understand the visual practices of sociology and to point out unused possibilities. I argue that the discourse on visual sociology, by assuming that photographs are less objective than text, is based on an asymmetric media-determinism and on a misleading notion of objectivity. Instead, I suggest to analyse media with the concept of translations. I introduce several kinds of translations, most centrally the distinction between tight and loose ones. I show that many sciences, such as biology, focus on tight translations, using a variety of media and manipulating both research objects and representations. Sociology, in contrast, uses both tight and loose translations, but uses the latter only for texts. For visuals, sociology restricts itself to what I call 'the documentary': focusing on mechanical recording technologies without manipulating either the object of research or the representation. I conclude by discussing three rare examples of what is largely excluded in sociology: visual loose translations, visual tight translations based on non-mechanical recording technologies, and visual tight translations based on mechanical recording technologies that include the manipulation of both object and representation.

  17. Magnetic axis alignment and the Poisson alignment reference system

    Science.gov (United States)

    Griffith, Lee V.; Schenz, Richard F.; Sommargren, Gary E.

    1989-01-01

    Three distinct metrological operations are necessary to align a free-electron laser (FEL): the magnetic axis must be located, a straight line reference (SLR) must be generated, and the magnetic axis must be related to the SLR. This paper begins with a review of the motivation for developing an alignment system that will assure better than 100 micrometer accuracy in the alignment of the magnetic axis throughout an FEL. The paper describes techniques for identifying the magnetic axis of solenoids, quadrupoles, and wiggler poles. Propagation of a laser beam is described to the extent of revealing sources of nonlinearity in the beam. Development and use of the Poisson line, a diffraction effect, is described in detail. Spheres in a large-diameter laser beam create Poisson lines and thus provide a necessary mechanism for gauging between the magnetic axis and the SLR. Procedures for installing FEL components and calibrating alignment fiducials to the magnetic axes of the components are also described. An error budget shows that the Poisson alignment reference system will make it possible to meet the alignment tolerances for an FEL.

  18. Packing tight Hamilton cycles in 3-uniform hypergraphs

    CERN Document Server

    Frieze, Alan; Loh, Po-Shen

    2010-01-01

    Let H be a 3-uniform hypergraph with N vertices. A tight Hamilton cycle C \\subset H is a collection of N edges for which there is an ordering of the vertices v_1, ..., v_N such that every triple of consecutive vertices {v_i, v_{i+1}, v_{i+2}} is an edge of C (indices are considered modulo N). We develop new techniques which enable us to prove that under certain natural pseudo-random conditions, almost all edges of H can be covered by edge-disjoint tight Hamilton cycles, for N divisible by 4. Consequently, we derive the corollary that random 3-uniform hypergraphs can be almost completely packed with tight Hamilton cycles w.h.p., for N divisible by 4 and P not too small. Along the way, we develop a similar result for packing Hamilton cycles in pseudo-random digraphs with even numbers of vertices.

  19. Claudin heterogeneity and control of lung tight junctions.

    Science.gov (United States)

    Koval, Michael

    2013-01-01

    Lung epithelial cells interconnected by tight junctions provide a barrier to the free diffusion of solutes into airspaces. Transmembrane tight junction proteins known as claudins are essential for epithelial barrier function. Claudins are regulated through interactions with each other that are coordinated with other transmembrane tight junction proteins and cytosolic scaffold proteins. Of the 14 claudins expressed by the alveolar epithelium, claudin-3, claudin-4, and claudin-18 are the most prominent; each confers unique properties to alveolar barrier function. In particular, a protective role for claudin-4 in preventing lung injury has emerged. By contrast, lung diseases that affect claudin expression and impair barrier function, including alcoholic lung syndrome and sepsis, prime the lung for pulmonary edema. Thus, approaches to restore and/or augment lung claudin expression provide potential targets for promoting healthy barrier function. PMID:23072447

  20. Harmonic Analysis of Linac Alignment

    CERN Document Server

    McCrady, Rodney C

    2005-01-01

    We have analyzed the requirements on alignment of the focusing elements (quadrupole doublets) in the Los Alamos Neutron Science Center (LANSCE) side coupled linac. The analysis is performed in terms of harmonics of the quardrupole spacing. This allows us to determine the effect of intentional deviations from a straight line, such as following the curvature of the Earth, and of unintentional deviations introduced by measurement and alignment errors. Results are compared to measured positions of the doublets.

  1. Expressive alignment language and implementation

    OpenAIRE

    Euzenat, Jérôme; Scharffe, François; Zimmermann, Antoine

    2007-01-01

    euzenat2007e This deliverable provides the description of an alignment language which is both expressive and independent from ontology languages. It defines the language through its abstract syntax and semantics depending on ontology language semantics. It then describes two concrete syntax: an exchange syntax in RDF/XML and a surface syntax for human consumption. Finally, it presents the current implementation of this expressive language within the Alignment API taking advantage of the OM...

  2. Non-Hermitian tight-binding network engineering

    CERN Document Server

    Longhi, Stefano

    2016-01-01

    We suggest a simple method to engineer a tight-binding quantum network based on proper coupling to an auxiliary non-Hermitian cluster. In particular, it is shown that effective complex non-Hermitian hopping rates can be realized with only complex on-site energies in the network. Three applications of the Hamiltonian engineering method are presented: the synthesis of a nearly transparent defect in an Hermitian linear lattice; the realization of the Fano-Anderson model with complex coupling; and the synthesis of a $\\mathcal{PT}$-symmetric tight-binding lattice with a bound state in the continuum.

  3. Parameter design and optimization of tight-lattice rod bundles

    International Nuclear Information System (INIS)

    Thin rod bundles with tight lattice are arranged according to the equilateral triangle grid, as the proportion of fuel is large, and the power density of core is high. Based on the analysis of the performance of core, the ABV-6M reactor is taken as the example, and two objective functions, power density and flow rate of coolant are proposed for optimization calculation. Diameter and pitch of rod are optimized by using GA method respectively. The results, which are considered to be safety in security checking, show that tight lattice is effective for improving the power density and other performances of the reactor core. (author)

  4. Sensing Characteristics of A Precision Aligner Using Moire Gratings for Precision Alignment System

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lizhong; Hideo Furuhashi; Yoshiyuki Uchida

    2001-01-01

    Sensing characteristics of a precision aligner using moire gratings for precision alignment sysem has been investigated. A differential moire alignment system and a modified alignment system were used. The influence of the setting accuracy of the gap length and inclination of gratings on the alignment accuracy has been studied experimentally and theoretically. Setting accuracy of the gap length less than 2.5μm is required in modified moire alignment. There is no influence of the gap length on the alignment accuracy in the differential alignment system. The inclination affects alignment accuracies in both differential and modified moire alignment systems.

  5. Practical aspects of implementing tight glucose control in the ICU

    NARCIS (Netherlands)

    Vogelzang, Mathijs; Ligtenberg, Jack J. M.

    2007-01-01

    Purpose of review The outcomes of intervention studies implementing intensive insulin therapy aimed at tight glucose control (TGC) are yet not conclusive. There is concern about an increasing incidence of hypoglycemic episodes. Normoglycemia is not easy to obtain in a 'real-life' ICU setting. To fac

  6. Scattering induced current in a tight-binding band

    CERN Document Server

    Bruneau, Laurent; Pillet, Claude-Alain

    2010-01-01

    In the single band tight-binding approximation, we consider the transport properties of an electron in a homogeneous static electric field. We show that repeated interactions of the electron with two-level systems in thermal equilibrium suppress the Bloch oscillations and induce a steady current, the statistical properties of which we study.

  7. DIDA: Distributed Indexing Dispatched Alignment.

    Directory of Open Access Journals (Sweden)

    Hamid Mohamadi

    Full Text Available One essential application in bioinformatics that is affected by the high-throughput sequencing data deluge is the sequence alignment problem, where nucleotide or amino acid sequences are queried against targets to find regions of close similarity. When queries are too many and/or targets are too large, the alignment process becomes computationally challenging. This is usually addressed by preprocessing techniques, where the queries and/or targets are indexed for easy access while searching for matches. When the target is static, such as in an established reference genome, the cost of indexing is amortized by reusing the generated index. However, when the targets are non-static, such as contigs in the intermediate steps of a de novo assembly process, a new index must be computed for each run. To address such scalability problems, we present DIDA, a novel framework that distributes the indexing and alignment tasks into smaller subtasks over a cluster of compute nodes. It provides a workflow beyond the common practice of embarrassingly parallel implementations. DIDA is a cost-effective, scalable and modular framework for the sequence alignment problem in terms of memory usage and runtime. It can be employed in large-scale alignments to draft genomes and intermediate stages of de novo assembly runs. The DIDA source code, sample files and user manual are available through http://www.bcgsc.ca/platform/bioinfo/software/dida. The software is released under the British Columbia Cancer Agency License (BCCA, and is free for academic use.

  8. Geodetic alignment of laser power installations

    International Nuclear Information System (INIS)

    Main problems occuring in applied geodesy under initial alignment of laser power installation optical channel are considered. Attention is paid to alignment of lens beamguide telescopic pairs and alignment quality control. Methods and means of geodetic measurements under alignment are indicated. Conclusions are made about the degree of working through certain aspects of the problem

  9. Photosensitive Polymers for Liquid Crystal Alignment

    Science.gov (United States)

    Mahilny, U. V.; Stankevich, A. I.; Trofimova, A. V.; Muravsky, A. A.; Murauski, A. A.

    The peculiarities of alignment of liquid crystal (LC) materials by the layers of photocrosslinkable polymers with side benzaldehyde groups are considered. The investigation of mechanism of photostimulated alignment by rubbed benzaldehyde layer is performed. The methods of creation of multidomain aligning layers on the basis of photostimulated rubbing alignment are described.

  10. Alignment method for parabolic trough solar concentrators

    Science.gov (United States)

    Diver, Richard B.

    2010-02-23

    A Theoretical Overlay Photographic (TOP) alignment method uses the overlay of a theoretical projected image of a perfectly aligned concentrator on a photographic image of the concentrator to align the mirror facets of a parabolic trough solar concentrator. The alignment method is practical and straightforward, and inherently aligns the mirror facets to the receiver. When integrated with clinometer measurements for which gravity and mechanical drag effects have been accounted for and which are made in a manner and location consistent with the alignment method, all of the mirrors on a common drive can be aligned and optimized for any concentrator orientation.

  11. Dewatering Techniques for Gas Recovery in Sichuan Gas Fields

    Institute of Scientific and Technical Information of China (English)

    Xu Kefang

    1996-01-01

    @@ Through several years' study for geology and development behavior of the gas fields, we realized that the water-bearing gas pools in Sichuan gas fields almost belong to enclosed weak elastic water drive gas pools, whether edge water gas pools or bottom water gas pools. According to the verification of drilling and production behavior data, in the periphery of Sichuan water-bearing gas pools, a screen is formed by gypsum salt, mudstone, or tight bed rock, with very low permeability, which blocks water percolation.

  12. Strategic Alignment and New Product Development

    DEFF Research Database (Denmark)

    Acur, Nuran; Kandemir, Destan; Boer, Harry

    2012-01-01

    of NPD performance indicators. Strategic planning and innovativeness appear to affect technological, market, and NPD-marketing alignment positively. Environmental munificence is negatively associated with NPD-marketing alignment, but has no effect on the two other forms of alignment. Technological change......Strategic alignment is widely accepted as a prerequisite for a firm’s success, but insight into the role of alignment in, and its impact on, the new product evelopment (NPD) process and its performance is less well developed. Most publications on this topic either focus on one form of alignment...... has a positive effect on technological alignment, a negative effect on NPD-marketing alignment, but no effect on market alignment. These findings suggest that internal capabilities are more likely to be associated with the development of strategic alignment than environmental factors are. Furthermore...

  13. Adaptive Processing for Sequence Alignment

    KAUST Repository

    Zidan, Mohammed Affan

    2012-01-26

    Disclosed are various embodiments for adaptive processing for sequence alignment. In one embodiment, among others, a method includes obtaining a query sequence and a plurality of database sequences. A first portion of the plurality of database sequences is distributed to a central processing unit (CPU) and a second portion of the plurality of database sequences is distributed to a graphical processing unit (GPU) based upon a predetermined splitting ratio associated with the plurality of database sequences, where the database sequences of the first portion are shorter than the database sequences of the second portion. A first alignment score for the query sequence is determined with the CPU based upon the first portion of the plurality of database sequences and a second alignment score for the query sequence is determined with the GPU based upon the second portion of the plurality of database sequences.

  14. Topology independent protein structural alignment

    Directory of Open Access Journals (Sweden)

    DasGupta Bhaskar

    2007-10-01

    Full Text Available Abstract Background Identifying structurally similar proteins with different chain topologies can aid studies in homology modeling, protein folding, protein design, and protein evolution. These include circular permuted protein structures, and the more general cases of non-cyclic permutations between similar structures, which are related by non-topological rearrangement beyond circular permutation. We present a method based on an approximation algorithm that finds sequence-order independent structural alignments that are close to optimal. We formulate the structural alignment problem as a special case of the maximum-weight independent set problem, and solve this computationally intensive problem approximately by iteratively solving relaxations of a corresponding integer programming problem. The resulting structural alignment is sequence order independent. Our method is also insensitive to insertions, deletions, and gaps. Results Using a novel similarity score and a statistical model for significance p-value, we are able to discover previously unknown circular permuted proteins between nucleoplasmin-core protein and auxin binding protein, between aspartate rasemase and 3-dehydrogenate dehydralase, as well as between migration inhibition factor and arginine repressor which involves an additional strand-swapping. We also report the finding of non-cyclic permuted protein structures existing in nature between AML1/core binding factor and ribofalvin synthase. Our method can be used for large scale alignment of protein structures regardless of the topology. Conclusion The approximation algorithm introduced in this work can find good solutions for the problem of protein structure alignment. Furthermore, this algorithm can detect topological differences between two spatially similar protein structures. The alignment between MIF and the arginine repressor demonstrates our algorithm's ability to detect structural similarities even when spatial

  15. Hardware Accelerated Sequence Alignment with Traceback

    OpenAIRE

    Scott Lloyd; Snell, Quinn O

    2009-01-01

    Biological sequence alignment is an essential tool used in molecular biology and biomedical applications. The growing volume of genetic data and the complexity of sequence alignment present a challenge in obtaining alignment results in a timely manner. Known methods to accelerate alignment on reconfigurable hardware only address sequence comparison, limit the sequence length, or exhibit memory and I/O bottlenecks. A space-efficient, global sequence alignment algorithm and architecture is pres...

  16. XUV ionization of aligned molecules

    Energy Technology Data Exchange (ETDEWEB)

    Kelkensberg, F.; Siu, W.; Gademann, G. [FOM Institute AMOLF, Science Park 104, NL-1098 XG Amsterdam (Netherlands); Rouzee, A.; Vrakking, M. J. J. [FOM Institute AMOLF, Science Park 104, NL-1098 XG Amsterdam (Netherlands); Max-Born-Institut, Max-Born Strasse 2A, D-12489 Berlin (Germany); Johnsson, P. [FOM Institute AMOLF, Science Park 104, NL-1098 XG Amsterdam (Netherlands); Department of Physics, Lund University, Post Office Box 118, SE-221 00 Lund (Sweden); Lucchini, M. [Department of Physics, Politecnico di Milano, Istituto di Fotonica e Nanotecnologie CNR-IFN, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Lucchese, R. R. [Department of Chemistry, Texas A and M University, College Station, Texas 77843-3255 (United States)

    2011-11-15

    New extreme-ultraviolet (XUV) light sources such as high-order-harmonic generation (HHG) and free-electron lasers (FELs), combined with laser-induced alignment techniques, enable novel methods for making molecular movies based on measuring molecular frame photoelectron angular distributions. Experiments are presented where CO{sub 2} molecules were impulsively aligned using a near-infrared laser and ionized using femtosecond XUV pulses obtained by HHG. Measured electron angular distributions reveal contributions from four orbitals and the onset of the influence of the molecular structure.

  17. Position list word aligned hybrid

    DEFF Research Database (Denmark)

    Deliege, Francois; Pedersen, Torben Bach

    2010-01-01

    of storage space. This paper presents the Position List Word Aligned Hybrid (PLWAH) compression scheme that improves significantly over WAH compression by better utilizing the available bits and new CPU instructions. For typical bit distributions, PLWAH compressed bitmaps are often half the size of WAH......Compressed bitmap indexes are increasingly used for efficiently querying very large and complex databases. The Word Aligned Hybrid (WAH) bitmap compression scheme is commonly recognized as the most efficient compression scheme in terms of CPU efficiency. However, WAH compressed bitmaps use a lot...

  18. Graphene as Gas Sensors

    Institute of Scientific and Technical Information of China (English)

    Hamze Mousavi

    2011-01-01

    The triatomic and tetratomic gas molecule adsorption effects on the electrical conductivity of graphene are investigated by the tight-binding model, Green's function method, and coherent potential approximation. We find that the electrical conductivity of graphene sheet is sensitive to the adsorption of these gases.

  19. Dynamics of tightly focused femtosecond laser pulses in water

    Science.gov (United States)

    Sreeja, S.; Leela, Ch; Rakesh Kumar, V.; Bagchi, Suman; Shuvan Prashant, T.; Radhakrishnan, P.; Tewari, Surya P.; Venugopal Rao, S.; Kiran, P. Prem

    2013-10-01

    The dynamics of tightly focused ultrashort (40 fs) pulses manifested in terms of supercontinuum emission (SCE) and cavitation-induced bubbles (CIB) resulting from propagation in water over a wide range of input powers (6 mW-1.8 W) are presented. The effect of linear polarization (LP) and circular polarization (CP) on SCE in different external focal geometries (f/6, f/7.5 and f/10) is investigated and the results are discussed. SCE with higher efficiency and a considerable spectral blue shift is observed under tight focusing conditions (f/6) compared to loose focusing conditions (f/10). At higher input powers, CIB along the axis of propagation are observed to be assisting deeper propagation of these short pulses and enhanced SCE.

  20. Differences between tight and loose cultures: a 33-nation study.

    Science.gov (United States)

    Gelfand, Michele J; Raver, Jana L; Nishii, Lisa; Leslie, Lisa M; Lun, Janetta; Lim, Beng Chong; Duan, Lili; Almaliach, Assaf; Ang, Soon; Arnadottir, Jakobina; Aycan, Zeynep; Boehnke, Klaus; Boski, Pawel; Cabecinhas, Rosa; Chan, Darius; Chhokar, Jagdeep; D'Amato, Alessia; Ferrer, Montse; Fischlmayr, Iris C; Fischer, Ronald; Fülöp, Marta; Georgas, James; Kashima, Emiko S; Kashima, Yoshishima; Kim, Kibum; Lempereur, Alain; Marquez, Patricia; Othman, Rozhan; Overlaet, Bert; Panagiotopoulou, Penny; Peltzer, Karl; Perez-Florizno, Lorena R; Ponomarenko, Larisa; Realo, Anu; Schei, Vidar; Schmitt, Manfred; Smith, Peter B; Soomro, Nazar; Szabo, Erna; Taveesin, Nalinee; Toyama, Midori; Van de Vliert, Evert; Vohra, Naharika; Ward, Colleen; Yamaguchi, Susumu

    2011-05-27

    With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change. PMID:21617077

  1. A tightly inducible riboswitch system in Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Ohbayashi, Ryudo; Akai, Hideto; Yoshikawa, Hirofumi; Hess, Wolfgang R; Watanabe, Satoru

    2016-07-14

    Cyanobacteria are photosynthetic microorganisms that serve as experimental model organisms for the study of photosynthesis, environmental stress responses, and the production of biofuels. Genetic tools for bioengineering have been developed as a result of such studies. However, there is still room for improvement for the tight control of experimental protein expression in these microorganisms. Here, we describe an expression system controlled by a theophylline-responsive riboswitch that we have constructed in the cyanobacterium Synechocystis sp. PCC 6803. We demonstrate that, in response to different theophylline concentrations, this riboswitch can tightly control green fluorescence protein expression in Synechocystis. Thus, this system is useful as a tool for genetic engineering and the synthetic biology of cyanobacteria. PMID:27250662

  2. Automatic generation of matrix element derivatives for tight binding models

    Science.gov (United States)

    Elena, Alin M.; Meister, Matthias

    2005-10-01

    Tight binding (TB) models are one approach to the quantum mechanical many-particle problem. An important role in TB models is played by hopping and overlap matrix elements between the orbitals on two atoms, which of course depend on the relative positions of the atoms involved. This dependence can be expressed with the help of Slater-Koster parameters, which are usually taken from tables. Recently, a way to generate these tables automatically was published. If TB approaches are applied to simulations of the dynamics of a system, also derivatives of matrix elements can appear. In this work we give general expressions for first and second derivatives of such matrix elements. Implemented in a tight binding computer program, like, for instance, DINAMO, they obviate the need to type all the required derivatives of all occurring matrix elements by hand.

  3. Aligned natural inflation with modulations

    Science.gov (United States)

    Choi, Kiwoon; Kim, Hyungjin

    2016-08-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  4. Laser-Beam-Alignment Controller

    Science.gov (United States)

    Krasowski, M. J.; Dickens, D. E.

    1995-01-01

    In laser-beam-alignment controller, images from video camera compared to reference patterns by fuzzy-logic pattern comparator. Results processed by fuzzy-logic microcontroller, which sends control signals to motor driver adjusting lens and pinhole in spatial filter.

  5. Aligned natural inflation with modulations

    CERN Document Server

    Choi, Kiwoon

    2015-01-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  6. Aligned natural inflation with modulations

    Directory of Open Access Journals (Sweden)

    Kiwoon Choi

    2016-08-01

    Full Text Available The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  7. Aligned natural inflation with modulations

    OpenAIRE

    Kiwoon Choi; Hyungjin Kim

    2016-01-01

    The weak gravity conjecture applied for the aligned natural inflation indicates that generically there can be a modulation of the inflaton potential, with a period determined by sub-Planckian axion scale. We study the oscillations in the primordial power spectrum induced by such modulation, and discuss the resulting observational constraints on the model.

  8. Self crimped and aligned fibers

    Directory of Open Access Journals (Sweden)

    Thinakaran Senthilram

    2011-05-01

    Full Text Available Electrospinning is one of the most successful means of producing nanofibers with enormous application potential. New methods of producing nanofibers without high voltages are presently being explored by researchers around the globe. In the present work, a facile method of producing aligned and crimped fibers with polycaprolactone by rotating the needle assembly is described.

  9. Materials processing with a tightly focused femtosecond vortex laser pulse

    OpenAIRE

    Hnatovsky, Cyril; Shvedov, Vladlen G.; Krolikowski, Wieslaw; Rode, Andrei V.

    2010-01-01

    This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1] and then focused using moderate and high numerical aperture optics (viz., NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. By controlling the pulse energy we consistently machine high-quality micron-size ring-shaped structures with less than...

  10. Materials processing with tightly focused femtosecond vortex laser beams

    OpenAIRE

    Hnatovsky, Cyril; Shvedov, Vladlen G.; Krolikowski, Wieslaw; Rode, Andrei V.

    2010-01-01

    This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1] and then focused using moderate and high numerical aperture optics (viz., NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. By controlling the pulse energy we consistently machine high-quality micron-size ring-shaped structures with less than...

  11. Ab initio calculation of tight-binding parameters

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, A.K.; Klepeis, J.E.

    1997-12-01

    We calculate ab initio values of tight-binding parameters for the f- electron metal Ce and various phases of Si, from local-density functional one-electron Hamiltonian and overlap matrix elements. Our approach allows us to unambiguously test the validity of the common minimal basis and two-center approximations as well as to determine the degree of transferability of both nonorthogonal and orthogonal hopping parameters in the cases considered.

  12. Hepatic tight junctions:From viral entry to cancer metastasis

    Institute of Scientific and Technical Information of China (English)

    Nikki; P; Lee; John; M; Luk

    2010-01-01

    The tight junction (TJ) is a critical cellular component for maintenance of tissue integrity, cellular interactions and cell-cell communications, and physiologically functions as the "great wall" against external agents and the surrounding hostile environment. During the host-pathogen evolution, viruses somehow found the key to unlock the gate for their entry into cells and to exploit and exhaust the host cells. In the liver, an array of TJ molecules is localized along the bile canaliculi forming the blood-...

  13. Tight binding description of the STM image of molecular chains

    OpenAIRE

    Calev, Yoel; Cohen, Hezy; Cuniberti, Gianaurelio; Nitzan, Abraham; Porath, Danny

    2004-01-01

    A tight binding model for scanning tunneling microscopy images of a molecule adsorbed on a metal surface is described. The model is similar in spirit to that used to analyze conduction along molecular wires connecting two metal leads and makes it possible to relate these two measurements and the information that may be gleaned from the corresponding results. In particular, the dependence of molecular conduction properties along and across a molecular chain on the chain length, intersite elect...

  14. Paroxysmal dystonic choreoathetosis: tight linkage to chromosome 2q.

    OpenAIRE

    Fink, J K; Rainer, S.; Wilkowski, J.; Jones, S. M.; Kume, A.; Hedera, P; Albin, R.; Mathay, J.; Girbach, L.; Varvil, T; Otterud, B; Leppert, M

    1996-01-01

    Paroxysmal dystonic choreoathetosis (PDC) is characterized by attacks of involuntary movements that last up to several hours and occur at rest both spontaneously and following caffeine or alcohol consumption. We analyzed a Polish-American kindred with autosomal dominant PDC and identified tight linkage between the disorder and microsatellite markers on chromosome 2q (maximum two-point LOD score 4.77; recombination fraction 0). Our results clearly establish the existence of a locus for autosom...

  15. Polyphase equiangular tight frames and abelian generalized quadrangles

    OpenAIRE

    Fickus, Matthew; Jasper, John; Mixon, Dustin G.; Peterson, Jesse D.; Watson, Cody E.

    2016-01-01

    An equiangular tight frame (ETF) is a type of optimal packing of lines in a finite-dimensional Hilbert space. ETFs arise in various applications, such as waveform design for wireless communication, compressed sensing, quantum information theory and algebraic coding theory. In a recent paper, signature matrices of ETFs were constructed from abelian distance regular covers of complete graphs. We extend this work, constructing ETF synthesis operators from abelian generalized quadrangles, and vic...

  16. Effect of a tight necktie on intraocular pressure

    Directory of Open Access Journals (Sweden)

    Božić Marija

    2012-01-01

    Full Text Available Introduction. Any factor causing constriction of the neck may lead to an increase in intraocular pressure. A tight necktie may result in increasing intraocular pressure, which could lead to an erroneous diagnosis and treatment of ocular hypertension or even glaucoma. This study was aimed at evaluating the effect of a tight necktie on intraocular pressure measurement using Goldmann applanation tonometry. Material and Methods. This study included forty eyes of 20 patients with primary open angle glaucoma and 20 healthy controls (all male. Intraocular pressure was measured without a necktie, 3 minutes after placing a tight necktie and 3 minutes after loosening it. Student’s t-test was used to analyze the data between two groups. The intraocular pressure measurements were subjected to paired t - test. The value p < 0.05 was considered statistically significant. A possible correlation between the age of subjects and intraocular pressure values was analyzed using linear regression (Pearson′. Results. A statistically significant difference was found in intraocular pressure readings in all three measurements between two tested groups (p<0.05. When analyzed within groups, statistical significance in intraocular pressure readings was found after loosening the necktie (<0.05. No correlation between the age of subjects and increased intraocular pressure was found in either tested group of subjects after the necktie had been tightened (r2=0.006, p=0.70 for primary open angle patients, r2=0.07, p=0.22 for healthy controls. Conclusion. Wearing a tight necktie for a limited period of time during the day could be considered as a possible risk factor for glaucoma development.

  17. Tight glycemic control in the ICU - is the earth flat?

    OpenAIRE

    Steil, Garry M.; Agus, Michael SD

    2014-01-01

    Tight glycemic control in the ICU has been shown to reduce mortality in some but not all prospective randomized control trials. Confounding the interpretation of these studies are differences in how the control was achieved and underlying incidence of hypoglycemia, which can be expected to be affected by the introduction of continuous glucose monitoring (CGM). In this issue of Critical Care, a consensus panel provides a list of the research priorities they believe are needed for CGM to become...

  18. Tight-binding parameters for charge transfer along DNA

    OpenAIRE

    Hawke, L. G.D.; Kalosakas, G.; Simserides, C.

    2009-01-01

    We systematically examine all the tight-binding parameters pertinent to charge transfer along DNA. The $\\pi$ molecular structure of the four DNA bases (adenine, thymine, cytosine, and guanine) is investigated by using the linear combination of atomic orbitals method with a recently introduced parametrization. The HOMO and LUMO wavefunctions and energies of DNA bases are discussed and then used for calculating the corresponding wavefunctions of the two B-DNA base-pairs (adenine-thymine and gua...

  19. Tight-binding modeling of charge migration in DNA devices

    OpenAIRE

    Cuniberti, G.; Macia, E.; Rodriguez, A.; R.A. Römer

    2007-01-01

    Long range charge transfer experiments in DNA oligomers and the subsequently measured -- and very diverse -- transport response of DNA wires in solid state experiments exemplifies the need for a thorough theoretical understanding of charge migration in DNA-based natural and artificial materials. Here we present a review of tight-binding models for DNA conduction which have the intrinsic merit of containing more structural information than plain rate-equation models while still retaining suffi...

  20. Grain Alignment and CMB Polarization Studies

    CERN Document Server

    Lazarian, A

    2008-01-01

    Polarized microwave emission from dust is an important foreground that may contaminate polarized CMB studies unless carefully accounted for. Modeling of polarization from dust requires a quantitative understanding of grain alignment. I review the current status of grain alignment theory outlining recent advances in quantitative description of the alignment. In particular, I show that the grain-alignment theory is a predictive one, and its results nicely match observations. Those indicate that the most important process of alignment is related to radiative torques acting on irregular grains. The recently developed analytical model of radiative torque alignment has proven to be a very efficient tool for predicting the degree of grain alignment. We expect the alignment theory to further mature before CMBPol flight, which would ensure a better accounting for the dust-related polarization. At the same time, CMBPol should provide the additional testing of grain alignment, clarifying the reliability of polarimetry f...

  1. Extensor Pollicis Longus Rupture after Mini TightRope Suspensionplasty.

    Science.gov (United States)

    Seetharaman, Mani; Vitale, Mark A; Desai, Kapil; Crowe, John F

    2016-05-01

    Background Arthritis of the first carpometacarpal (CMC) joint has been surgically treated in multiple ways with varying levels of success as measured by subjective and objective measures. Trapeziectomy with numerous variations in suspensionplasty comprises one of the more commonly used surgical procedures. Recently, the Mini TightRope apparatus has been utilized as a new method for achieving suspensionplasty, and as such lacks significant review of use and safety in the literature. Case Description An extensor pollicis longus (EPL) rupture following a trapeziectomy and Mini TightRope suspensionplasty for CMC arthritis of the thumb is presented. The patient successfully underwent an extensor indicis proprius (EIP) to EPL transfer to treat this complication. Literature Review There is well-established documentation of injury to the extensor tendons from orthopedic hardware such as volar locking plates. Regarding use of the Mini TightRope apparatus, guidelines for placement of the suture button include caution to place the button away from the EPL tendon to minimize the chance of tendon irritation. Additionally, FiberWire sutures, a component of the apparatus, have been shown to demonstrate soft tissue reactions with adjacent inflammatory response. Published reports on adverse events utilizing this device have been limited to case reports including an index metacarpal fracture. Clinical Relevance The aim of this case report was to cite an occurrence of EPL rupture following its use and discuss the possibilities of its direct contribution. PMID:27104081

  2. Helium-tight Laser Beam Welding of Aluminum with Brillant Laser Beam Radiation

    Science.gov (United States)

    Heinen, Paul; Wu, Hao; Olowinsky, Alexander; Gillner, Arnold

    The substitution of steel as base metal for casings and packaging applications has increased during the last years. Especially aluminum with advantages in weight and machining effort has become a versatile solution for applications in fine mechanics (e.g. sensor housings) and automotive applications. Joining of aluminum components is more critical due to possible crack formation in the joining seam and uneven seam geometry. With the high intensity of brillant laser beam sources the specific challenges of aluminum welding can be overcome. Due to its hydrogen affinity and high degree of reflection for laser radiation at a wavelength of 1 μm (95%) aluminum needs to be welded with proper shielding gas support and high beam quality in order to avoid seam defects. Cracks and pores can lead to non-sufficient tightness for sensor applications and early failure. Housing components have been joined to form a functioning unit in order to seal electrical or measuring components, which are helium-tight for these applications.

  3. Pin-Align: A New Dynamic Programming Approach to Align Protein-Protein Interaction Networks

    OpenAIRE

    Farid Amir-Ghiasvand; Abbas Nowzari-Dalini; Vida Momenzadeh

    2014-01-01

    To date, few tools for aligning protein-protein interaction networks have been suggested. These tools typically find conserved interaction patterns using various local or global alignment algorithms. However, the improvement of the speed, scalability, simplification, and accuracy of network alignment tools is still the target of new researches. In this paper, we introduce Pin-Align, a new tool for local alignment of protein-protein interaction networks. Pin-Align accuracy is tested on protein...

  4. Behavior of mixed-oxide fuel elements in a tight bundle under duty-cycle conditions

    International Nuclear Information System (INIS)

    The irradiation behavior of the TOB-10 fuel pins was comparable with that obtained in the single pin tests. There was no significant effect that could be directly attributed to tight bundle configuration. The postirradiation examination data provided information on the axial migration of cesium and its effect on cladding strain. Severe fuel/cladding chemical interaction (FCCI), which resulted in substantial cladding thinning and probably restricted venting of fission gas from the fuel column into the pin plena, apparently caused the earlier-than-expected cladding breaches in the D9-clad pins. No such severe FCCI was noted in the 316SS-clad pins. At the time of test termination, the overall cladding strain from creep and swelling was insufficient to cause bundle closure. Consequently, there would have been minimal pin bundle-duct interaction in the subassembly. Neither of the breaches appeared to be induced by pin bundle-duct interaction. (author)

  5. Hydrogen bonding in the protic ionic liquid triethylammonium nitrate explored by density functional tight binding simulations

    CERN Document Server

    Zentel, Tobias

    2016-01-01

    The applicability of the density functional based tight binding (DFTB) method to the description of hydrogen bond dynamics and infrared spectroscopy is addressed for the exemplary protic ionic liquid triethylammonium nitrate. Potential energy curves for proton transfer in gas and liquid phase are shown to be comparable to high level coupled cluster theory in the thermally accessible range of bond lengths. Geometric correlations in the hydrogen bond dynamics are analyzed for a cluster of six ion pairs. Comparing DFTB and regular DFT data lends further support for the reliability of the DFTB method. Therefore, DFTB bulk simulations are performed to quantify the extent of geometric correlations in terms of Pauling's bond order model. Further, infrared (IR) absorption spectra are obtained and analyzed putting emphasis on the signatures of hydrogen bonding in the NH-stretching and far IR hydrogen bond range.

  6. Shuttle onboard IMU alignment methods

    Science.gov (United States)

    Henderson, D. M.

    1976-01-01

    The current approach to the shuttle IMU alignment is based solely on the Apollo Deterministic Method. This method is simple, fast, reliable and provides an accurate estimate for the present cluster to mean of 1,950 transformation matrix. If four or more star sightings are available, the application of least squares analysis can be utilized. The least squares method offers the next level of sophistication to the IMU alignment solution. The least squares method studied shows that a more accurate estimate for the misalignment angles is computed, and the IMU drift rates are a free by-product of the analysis. Core storage requirements are considerably more; estimated 20 to 30 times the core required for the Apollo Deterministic Method. The least squares method offers an intermediate solution utilizing as much data that is available without a complete statistical analysis as in Kalman filtering.

  7. Aligning seminars with Bologna requirements

    DEFF Research Database (Denmark)

    Lueg, Klarissa; Lueg, Rainer; Lauridsen, Ole

    2015-01-01

    Changes in public policy, such as the Bologna Process, require students to be equipped with multifunctional competencies to master relevant tasks in unfamiliar situations. Achieving this goal might imply a change in many curricula toward deeper learning. As a didactical means to achieve deep...... learning results, the authors suggest reciprocal peer tutoring (RPT); as a conceptual framework the authors suggest the SOLO (Structure of Observed Learning Outcomes) taxonomy and constructive alignment as suggested by Biggs and Tang. Our study presents results from the introduction of RPT in a large...... course. The authors find that RPT produces satisfying learning outcomes, active students, and ideal constructive alignments of the seminar content with the exam, the intended learning outcomes, and the requirements of the Bologna Process. Our data, which comprise surveys and evaluations from both faculty...

  8. Prism Window for Optical Alignment

    Science.gov (United States)

    Tang, Hong

    2008-01-01

    A prism window has been devised for use, with an autocollimator, in aligning optical components that are (1) required to be oriented parallel to each other and/or at a specified angle of incidence with respect to a common optical path and (2) mounted at different positions along the common optical path. The prism window can also be used to align a single optical component at a specified angle of incidence. Prism windows could be generally useful for orienting optical components in manufacture of optical instruments. "Prism window" denotes an application-specific unit comprising two beam-splitter windows that are bonded together at an angle chosen to obtain the specified angle of incidence.

  9. Aligned mesoporous architectures and devices.

    Energy Technology Data Exchange (ETDEWEB)

    Brinker, C. Jeffrey; Lu, Yunfeng (University of California Los Angeles, Los Angeles, CA)

    2011-03-01

    This is the final report for the Presidential Early Career Award for Science and Engineering - PECASE (LDRD projects 93369 and 118841) awarded to Professor Yunfeng Lu (Tulane University and University of California-Los Angeles). During the last decade, mesoporous materials with tunable periodic pores have been synthesized using surfactant liquid crystalline as templates, opening a new avenue for a wide spectrum of applications. However, the applications are somewhat limited by the unfavorabe pore orientation of these materials. Although substantial effort has been devoted to align the pore channels, fabrication of mesoporous materials with perpendicular pore channels remains challenging. This project focused on fabrication of mesoporous materials with perpendicularly aligned pore channels. We demonstrated structures for use in water purification, separation, sensors, templated synthesis, microelectronics, optics, controlled release, and highly selective catalysts.

  10. Intrinsic Galaxy Alignments and Weak Gravitational Lensing

    CERN Document Server

    Heavens, A F

    2001-01-01

    Gravitational lensing causes background galaxy images to become aligned, and the statistical characteristics of the image alignments can then be used to constrain the power spectrum of mass fluctuations. Analyses of gravitational lensing assume that intrinsic galaxy alignments are negligible, but if this assumption does not hold, then the interpretation of image alignments will be in error. As gravitational lensing experiments become more ambitious and seek very low-level alignments arising from lensing by large-scale structure, it becomes more important to estimate the level of intrinsic alignment in the galaxy population. In this article, I review the cluster of independent theoretical studies of this issue, as well as the current observational status. Theoretically, the calculation of intrinsic alignments is by no means straightforward, but some consensus has emerged from the existing works, despite each making very different assumptions. This consensus is that a) intrinsic alignments are a small but non-n...

  11. RDF Graph Alignment with Bisimulation

    OpenAIRE

    Buneman, Peter; Staworko, Sławek

    2016-01-01

    We investigate the problem of aligning two RDF databases, an essential problem in understanding the evolution of ontologies. Our approaches address three fundamental challenges: 1) the use of "blank" (null) names, 2) ontology changes in which different names are used to identify the same entity, and 3) small changes in the data values as well as small changes in the graph structure of the RDF database. We propose approaches inspired by the classical notion of graph bisimulation and extend the...

  12. Structural analysis of aligned RNAs.

    Science.gov (United States)

    Voss, Björn

    2006-01-01

    The knowledge about classes of non-coding RNAs (ncRNAs) is growing very fast and it is mainly the structure which is the common characteristic property shared by members of the same class. For correct characterization of such classes it is therefore of great importance to analyse the structural features in great detail. In this manuscript I present RNAlishapes which combines various secondary structure analysis methods, such as suboptimal folding and shape abstraction, with a comparative approach known as RNA alignment folding. RNAlishapes makes use of an extended thermodynamic model and covariance scoring, which allows to reward covariation of paired bases. Applying the algorithm to a set of bacterial trp-operon leaders using shape abstraction it was able to identify the two alternating conformations of this attenuator. Besides providing in-depth analysis methods for aligned RNAs, the tool also shows a fairly well prediction accuracy. Therefore, RNAlishapes provides the community with a powerful tool for structural analysis of classes of RNAs and is also a reasonable method for consensus structure prediction based on sequence alignments. RNAlishapes is available for online use and download at http://rna.cyanolab.de. PMID:17020924

  13. Hardware Acceleration of Bioinformatics Sequence Alignment Applications

    OpenAIRE

    Hasan, L.

    2011-01-01

    Biological sequence alignment is an important and challenging task in bioinformatics. Alignment may be defined as an arrangement of two or more DNA or protein sequences to highlight the regions of their similarity. Sequence alignment is used to infer the evolutionary relationship between a set of protein or DNA sequences. An accurate alignment can provide valuable information for experimentation on the newly found sequences. It is indispensable in basic research as well as in practical applic...

  14. Inferring comprehensible business/ICT alignment rules.

    OpenAIRE

    Cumps, Bjorn; Martens, David; De Backer, Manu; Haesen, Raf; Viaene, Stijn; Dedene, Guido; Baesens, Bart; Snoeck, Monique

    2009-01-01

    We inferred business rules for business/ICT alignment by applying a novel rule induction algorithm on a data set containing rich alignment information polled from 641 organisations in 7 European countries. The alignment rule set was created using AntMiner+, a rule induction technique with a reputation of inducing accurate, comprehensible, and intuitive predictive models from data. Our data set consisted of 18 alignment practices distilled from an analysis of relevant publications and validate...

  15. The Alignment and Assembly for EAST Tokamak Device

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    EAST (HT-7U) is a large fusion experimental device. It is a full superconducting tokamak with 1 MA of plasma current, 1000 s of plasma duration, high elongation and triangularity. It mainly consists of superconducting magnets of poloidal and toroidal field (PF& TF),vacuum vessel (VV), thermal radiation shield (TRS) and cryostat vessel (CV). The significant difficulty for assembly of EAST is tight installation tolerances, which are in the order of several tenth of a millimeter. In particular, the alignment of plasma facing components to the magnetic axis of the device is less than ± 0.5 mm.At present, a reasonable assembly process of EAST has been defined, and based on it, the alignment method for EAST, including the survey control network, the location of the main components in different directions, the magnetic axis determination and the accurate positioning of the plasma facing components inside of the vacuum vessel and so on, has been defined by using the sophisticated optical metrology system (SOMS).This paper describes the assembly procedure of EAST and the installation tolerances associated with the main components. Meanwhile, how to establish the assembly survey control network,magnetic axis determination methods, are introduced in detail.

  16. Materials processing with a tightly focused femtosecond laser vortex pulse.

    Science.gov (United States)

    Hnatovsky, Cyril; Shvedov, Vladlen G; Krolikowski, Wieslaw; Rode, Andrei V

    2010-10-15

    In this Letter we present the first (to our knowledge) demonstration of material modification using tightly focused single femtosecond laser vortex pulses. Double-charge femtosecond vortices were synthesized with a polarization-singularity beam converter based on light propagation in a uniaxial anisotropic medium and then focused using moderate- and high-NA optics (viz., NA=0.45 and 0.9) to ablate fused silica and soda-lime glass. By controlling the pulse energy, we consistently machine micrometer-size ring-shaped structures with <100nm uniform groove thickness. PMID:20967085

  17. A characterization of tight and dual generalized translation invariant frames

    DEFF Research Database (Denmark)

    Jakobsen, Mads Sielemann; Lemvig, Jakob

    2015-01-01

    We present results concerning generalized translation invariant (GTI) systems on a second countable locally compact abelian group G. These are systems with a family of generators {gj, P}jεJ, pεPJ ⊂ L2(G), where J is a countable index set, and Pj, j ε J are certain measure spaces. Furthermore, for...... systems form tight frames, and when two GTI Bessel systems form dual frames for L2(G). In particular, this offers a unified approach to the theory of discrete and continuous frames and, e.g., yields well known results for discrete and continuous Gabor and wavelet systems....

  18. Process for tightly sealing nuclear reactor fuel rods

    International Nuclear Information System (INIS)

    This invention refers to a process for pressurising and tightly sealing fuel rods used in nuclear reactors. The fuel rods utilised in commercial nuclear reactors are usually composed of a zircaloy tubular cladding of around 15 mm in diameter and up to 5 m long, filled with fuel pellets maintained in place by end plugs sealed on each end of the cladding. The main purpose of the invention is to promote a process using laser beam welding equipment to seal the end plugs on the fuel rods, drill a pressurising hole in one of the end plugs and hermetically seal the hole after the fuel rod has been placed under pressure

  19. Role of the tight junction protein claudin-6

    OpenAIRE

    Stier, Alexander

    2013-01-01

    In this thesis the influence of the TJ protein claudin-2 (Cld-6) on the transepithelial water transport in MDCK-C7 cells was investigated. It has been shown that Cld-6 overexpression in mouse causes a strong trans-epidermal water loss and thereby leads to death shortly after birth. The kidney cell line MDCK-C7 grows confluent and single-layered, forms TJ and serves as a model for a tight epithelium. The MDCK-C7 cells were stably transfected with Cld-6 cDNA (C7-Cld-6), the same cells transfect...

  20. Tight glycemic control in the ICU - is the earth flat?

    Science.gov (United States)

    Steil, Garry M; Agus, Michael S D

    2014-01-01

    Tight glycemic control in the ICU has been shown to reduce mortality in some but not all prospective randomized control trials. Confounding the interpretation of these studies are differences in how the control was achieved and underlying incidence of hypoglycemia, which can be expected to be affected by the introduction of continuous glucose monitoring (CGM). In this issue of Critical Care, a consensus panel provides a list of the research priorities they believe are needed for CGM to become routine practice in the ICU. We reflect on these recommendations and consider the implications for using CGM today. PMID:25041720

  1. Containment leak-tightness enhancement at VVER 440 NPPs

    International Nuclear Information System (INIS)

    The hermetic compartments of VVER 440 NPPs fulfil the function of the containment used at NPPs all over the word. The purpose of the containment is to protect the NPP personal against radioactive impact as well as to prevent radioactive leakage to the environment during a lost of coolant accident. Leak-tightness enhancement in NPPs with VVER 440/213 and VVER 440/230 reactors is an important safety issue. New procedures, measures and methods were adopted at NPPs in Mochovce, J. Bohunice, Dukovany and Paks for leak identification and sealing works performed by VUEZ Levice. (authors)

  2. Solving MAX-2-SAT Above a Tight Lower Bound

    CERN Document Server

    Gutin, Gregory; Szeider, Stefan; Yeo, Anders

    2009-01-01

    We present an exact algorithm that decides in time $m^{O(1)} + 2^{O(k^2)}$ whether a given set of $m$ binary clauses admits a truth assignment that satisfies at least $(3m+k)/4$ clauses. Thus \\textsc{Max-2-Sat} is fixed-parameter tractable when parameterized above the tight lower bound $3m/4$. Our algorithm is based on a polynomial-time data reduction procedure that reduces a problem instance to an equivalent one with $O(k^2)$ variables.

  3. Materials processing with a tightly focused femtosecond vortex laser pulse

    CERN Document Server

    Hnatovsky, Cyril; Krolikowski, Wieslaw; Rode, Andrei V

    2010-01-01

    This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1] and then focused using moderate and high numerical aperture optics (viz., NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. By controlling the pulse energy we consistently machine high-quality micron-size ring-shaped structures with less than 100 nm uniform groove thickness.

  4. Materials processing with tightly focused femtosecond vortex laser beams

    CERN Document Server

    Hnatovsky, Cyril; Krolikowski, Wieslaw; Rode, Andrei V

    2010-01-01

    This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1] and then focused using moderate and high numerical aperture optics (viz., NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. By controlling the pulse energy we consistently machine high-quality micron-size ring-shaped structures with less than 100 nm uniform groove thickness.

  5. Effects of gastrocnemius tightness on forefoot during gait.

    Science.gov (United States)

    Cazeau, Cyrille; Stiglitz, Yves

    2014-12-01

    The gastrocnemius is the main muscle of the posterior compartment of the leg. As a biarticular muscle it has specific biomechanical propertiess. This article discusses these properties combining the major biomechanical topics of anatomy, dynamics, kinetics, and electromyography. This muscle is remarkable in that it has very low energy consumption and very high mechanical efficacy. In addition to the biomechanical features, the consequences of its tightness are discussed. The dysfunction also appears in all the biomechanical topics and clarifies the reasons of the location of symptoms in the midfoot and on the plantar aspect of the forefoot.

  6. Tight-binding approach to strain-dependent DNA electronics

    Science.gov (United States)

    Malakooti, Sadeq; Hedin, Eric; Joe, Yong

    2013-07-01

    Small mechanical strain perturbations are considered in calculations of the poly(G)-poly(C) DNA molecular electronic structure, using a tight-binding framework in conjunction with the theories of Slater-Koster and linear elasticity. Results reveal a strain-induced band gap for DNA which is linearly dependent on the induced strain. Local density of states calculations expose that the contribution of the guanine-cytosine base pairs in the charge transport mechanism is significantly enhanced relative to the backbones when DNA is compressed. Transport investigations also disclose a strain-induced metal-semiconductor transition for the DNA molecule, which suggests possible potential uses for sensing applications.

  7. Ultrafast electron diffraction from aligned molecules

    Energy Technology Data Exchange (ETDEWEB)

    Centurion, Martin [Univ. of Nebraska, Lincoln, NE (United States)

    2015-08-17

    The aim of this project was to record time-resolved electron diffraction patterns of aligned molecules and to reconstruct the 3D molecular structure. The molecules are aligned non-adiabatically using a femtosecond laser pulse. A femtosecond electron pulse then records a diffraction pattern while the molecules are aligned. The diffraction patterns are then be processed to obtain the molecular structure.

  8. Beam alignment system for laser welding system

    International Nuclear Information System (INIS)

    The patent describes a beam alignment system for laser welding work pieces, such as fuel rod grids for nuclear fuel assemblies. The apparatus for performing various laser-machining comprises a beam alignment system including alignment target means, as well as means for emitting, directing and focusing the laser beam. (U.K.)

  9. Vertically aligned nanostructure scanning probe microscope tips

    Science.gov (United States)

    Guillorn, Michael A.; Ilic, Bojan; Melechko, Anatoli V.; Merkulov, Vladimir I.; Lowndes, Douglas H.; Simpson, Michael L.

    2006-12-19

    Methods and apparatus are described for cantilever structures that include a vertically aligned nanostructure, especially vertically aligned carbon nanofiber scanning probe microscope tips. An apparatus includes a cantilever structure including a substrate including a cantilever body, that optionally includes a doped layer, and a vertically aligned nanostructure coupled to the cantilever body.

  10. Alignment of lower-limb prostheses.

    Science.gov (United States)

    Zahedi, M S; Spence, W D; Solomonidis, S E; Paul, J P

    1986-04-01

    Alignment of a prosthesis is defined as the position of the socket relative to the other prosthetic components of the limb. During dynamic alignment the prosthetist, using subjective judgment and feedback from the patient, aims to achieve the most suitable limb geometry for best function and comfort. Until recently it was generally believed that a patient could only be satisfied with a unique "optimum alignment." The purpose of this systematic study of lower-limb alignment parameters was to gain an understanding of the factors that make a limb configuration or optimum alignment, acceptable to the patient, and to obtain a measure of the variation of this alignment that would be acceptable to the amputee. In this paper, the acceptable range of alignments for 10 below- and 10 above-knee amputees are established. Three prosthetists were involved in the majority of the 183 below-knee and 100 above-knee fittings, although several other prosthetists were also involved. The effects of each different prosthetist on the established range of alignment for each patient are reported to be significant. It is now established that an amputee can tolerate several alignments ranging in some parameters by as much as 148 mm in shifts and 17 degrees in tilts. This paper describes the method of defining and measuring the alignment of lower-limb prostheses. It presents quantitatively established values for bench alignment position and the range of adjustment required for incorporation into the design of new alignment units.

  11. Hardware Acceleration of Bioinformatics Sequence Alignment Applications

    NARCIS (Netherlands)

    Hasan, L.

    2011-01-01

    Biological sequence alignment is an important and challenging task in bioinformatics. Alignment may be defined as an arrangement of two or more DNA or protein sequences to highlight the regions of their similarity. Sequence alignment is used to infer the evolutionary relationship between a set of pr

  12. Shift dynamics of capillary self-alignment

    NARCIS (Netherlands)

    Arutinov, G.; Mastrangeli, M.; Smits, E.C.P.; Heck, G.V.; Schoo, H.F.M.; Toonder, J.J.M. den; Dietzel, A.H.

    2014-01-01

    This paper describes the dynamics of capillary self-alignment of components with initial shift offsets from matching receptor sites. The analysis of the full uniaxial self-alignment dynamics of foil-based mesoscopic dies from pre-alignment to final settling evidenced three distinct, sequential regim

  13. Inferring comprehensible business/ICT alignment rules

    NARCIS (Netherlands)

    B. Cumps; D. Martens; M. De Backer; R. Haesen; S. Viaene; G. Dedene; B. Baesens; M. Snoeck

    2009-01-01

    We inferred business rules for business/ICT alignment by applying a novel rule induction algorithm on a data set containing rich alignment information polled from 641 organisations in 7 European countries. The alignment rule set was created using AntMiner+, a rule induction technique with a reputati

  14. Alignments Of Black Holes With Their Warped Accretion Disks And Episodic Lifetimes Of Active Galactic Nuclei

    CERN Document Server

    Li, Yan-Rong; Cheng, Cheng; Qiu, Jie

    2015-01-01

    Warped accretion disks have attracted intensive attention because of their critical role on shaping the spin of supermassive massive black holes (SMBHs) through the Bardeen-Petterson effect, a general relativistic effect that leads to final alignments or anti-alignments between black holes and warped accretion disks. We study such alignment processes by explicitly taking into account the finite sizes of accretion disks and the episodic lifetimes of AGNs that delineate the duration of gas fueling onto accretion disks. We employ an approximate global model to simulate the evolution of accretion disks, allowing to determine the gravitomagnetic torque that drives the alignments in a quite simple way. We then track down the evolutionary paths for mass and spin of black holes both in a single activity episode and over a series of episodes. Given with randomly and isotropically oriented gas fueling over episodes, we calculate the spin evolution with different episodic lifetimes and find that it is quite sensitive to...

  15. 致密砂岩储层非均质性对气水分布的影响—以苏里格气田苏X区块盒8段为例%Effect of Tight Sandstone Reservoir Heterogeneity on The Distribution of Gas and Water

    Institute of Scientific and Technical Information of China (English)

    李生荣; 金文辉; 张波; 王姝; 巩高飞

    2015-01-01

    通过对苏里格气田苏X区块岩心、测井及测试资料的统计分析和研究,分别讨论了研究区石盒子组8段,盒8上1、盒8上2、盒8下1和盒8下2四个小层的非均质性特征,研究表明,盒8段各小层层内、层间及平面非均质性整体较强.并分析了各类非均质性对研究区气水分布的影响,盒8段储层的层内、层间及平面非均质性共同作用导致了研究区盒8段储层中水体往往是孤立的、呈透镜状,分散、横向上互不连通.%Based on core,logging and test data statistical analysis and research of Su X block in the SuLiGe Gasfield,Shihezi group 8 section in the study are discussed respectively,He 8 upper 1,He 8 upper 2,He 8 under 1`and He 8 under 2four small layers heterogeneity characteristics.The research shows that,each small layer of He 8 section inner layer,interlayer and plane heterogeneity within the overall is stronger.And then analyzes all kinds of heterogeneity effects on gas water distribution in the studied area,He 8 section of the reservoir layer, interlayer and plane heterogeneity within working together resulted in that the water is often isolated,lenticular,scattered,horizontal,and not communicated with each other in the study area in He 8 section reservoir.

  16. Instantaneous Observability of Tightly Coupled SINS/GPS during Maneuvers.

    Science.gov (United States)

    Jiang, Junxiang; Yu, Fei; Lan, Haiyu; Dong, Qianhui

    2016-01-01

    The tightly coupled strapdown inertial navigation system (SINS)/global position system (GPS) has been widely used. The system observability determines whether the system state can be estimated by a filter efficiently or not. In this paper, the observability analysis of a two-channel and a three-channel tightly coupled SINS/GPS are performed, respectively, during arbitrary translational maneuvers and angle maneuvers, where the translational maneuver and angle maneuver are modeled. A novel instantaneous observability matrix (IOM) based on a reconstructed psi-angle model is proposed to make the theoretical analysis simpler, which starts from the observability definition directly. Based on the IOM, a series of theoretical analysis are performed. Analysis results show that almost all kinds of translational maneuver and angle maneuver can make a three-channel system instantaneously observable, but there is no one translational maneuver or angle maneuver can make a two-channel system instantaneously observable. The system's performance is investigated when the system is not instantaneously observable. A series of simulation studies based on EKF are performed to confirm the analytic conclusions. PMID:27240369

  17. Instantaneous Observability of Tightly Coupled SINS/GPS during Maneuvers

    Directory of Open Access Journals (Sweden)

    Junxiang Jiang

    2016-05-01

    Full Text Available The tightly coupled strapdown inertial navigation system (SINS/global position system (GPS has been widely used. The system observability determines whether the system state can be estimated by a filter efficiently or not. In this paper, the observability analysis of a two-channel and a three-channel tightly coupled SINS/GPS are performed, respectively, during arbitrary translational maneuvers and angle maneuvers, where the translational maneuver and angle maneuver are modeled. A novel instantaneous observability matrix (IOM based on a reconstructed psi-angle model is proposed to make the theoretical analysis simpler, which starts from the observability definition directly. Based on the IOM, a series of theoretical analysis are performed. Analysis results show that almost all kinds of translational maneuver and angle maneuver can make a three-channel system instantaneously observable, but there is no one translational maneuver or angle maneuver can make a two-channel system instantaneously observable. The system’s performance is investigated when the system is not instantaneously observable. A series of simulation studies based on EKF are performed to confirm the analytic conclusions.

  18. RevTrans: multiple alignment of coding DNA from aligned amino acid sequences

    DEFF Research Database (Denmark)

    Wernersson, Rasmus; Pedersen, Anders Gorm

    2003-01-01

    proteins. It is therefore preferable to align coding DNA at the amino acid level and it is for this purpose we have constructed the program RevTrans. RevTrans constructs a multiple DNA alignment by: (i) translating the DNA; (ii) aligning the resulting peptide sequences; and (iii) building a multiple DNA...... alignment by 'reverse translation' of the aligned protein sequences. In the resulting DNA alignment, gaps occur in groups of three corresponding to entire codons, and analogous codon positions are therefore always lined up. These features are useful when constructing multiple DNA alignments for phylogenetic...

  19. Aligning molecules with intense nonresonant laser fields

    DEFF Research Database (Denmark)

    Larsen, J.J.; Safvan, C.P.; Sakai, H.;

    1999-01-01

    Molecules in a seeded supersonic beam are aligned by the interaction between an intense nonresonant linearly polarized laser field and the molecular polarizability. We demonstrate the general applicability of the scheme by aligning I2, ICl, CS2, CH3I, and C6H5I molecules. The alignment is probed...... by mass selective two dimensional imaging of the photofragment ions produced by femtosecond laser pulses. Calculations on the degree of alignment of I2 are in good agreement with the experiments. We discuss some future applications of laser aligned molecules....

  20. MANAGING TIGHT BINDING RECEPTORS FOR NEW SPEARATIONS TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    DARYLE H BUSCH RICHARD S GIVENS

    2004-12-10

    Much of the earth's pollution involves compounds of the metallic elements, including actinides, strontium, cesium, technetium, and RCRA metals. Metal ions bind to molecules called ligands, which are the molecular tools that can manipulate the metal ions under most conditions. This DOE-EMSP sponsored program strives (1) to provide the foundations for using the most powerful ligands in transformational separations technologies and (2) to produce seminal examples of their applications to separations appropriate to the DOE EM mission. These ultra tight-binding ligands can capture metal ions in the most competitive of circumstances (from mineralized sites, lesser ligands, and even extremely dilute solutions), but they react so slowly that they are useless in traditional separations methodologies. Two attacks on this problem are underway. The first accommodates to the challenging molecular lethargy by developing a seminal slow separations methodology termed the soil poultice. The second designs ligands that are only tight-binding while wrapped around the targeted metal ion, but can be put in place by switch-binding and removed by switch-release. We envision a kind of molecular switching process to accelerate the union between metal ion and tight-binding ligand. Molecular switching processes are suggested for overcoming the slow natural equilibration rate with which ultra tight-binding ligands combine with metal ions. Ligands that bind relatively weakly combine with metal ions rapidly, so the trick is to convert a ligand from a weak, rapidly binding species to a powerful, slow releasing ligand--during the binding of the ligand to the metal ion. Such switch-binding ligands must react with themselves, and the reaction must take place under the influence of the metal ion. For example, our generation 1 ligands showed that a well-designed linear ligand with ends that readily combine, forms a cyclic molecule when it wraps around a metal ion. Our generation 2 ligands are

  1. Galaxy alignments: Theory, modelling and simulations

    CERN Document Server

    Kiessling, Alina; Joachimi, Benjamin; Kirk, Donnacha; Kitching, Thomas D; Leonard, Adrienne; Mandelbaum, Rachel; Schäfer, Björn Malte; Sifón, Cristóbal; Brown, Michael L; Rassat, Anais

    2015-01-01

    The shapes of galaxies are not randomly oriented on the sky. During the galaxy formation and evolution process, environment has a strong influence, as tidal gravitational fields in large-scale structure tend to align the shapes and angular momenta of nearby galaxies. Additionally, events such as galaxy mergers affect the relative alignments of galaxies throughout their history. These "intrinsic galaxy alignments" are known to exist, but are still poorly understood. This review will offer a pedagogical introduction to the current theories that describe intrinsic galaxy alignments, including the apparent difference in intrinsic alignment between early- and late-type galaxies and the latest efforts to model them analytically. It will then describe the ongoing efforts to simulate intrinsic alignments using both $N$-body and hydrodynamic simulations. Due to the relative youth of this field, there is still much to be done to understand intrinsic galaxy alignments and this review summarises the current state of the ...

  2. Aligning Sequences by Minimum Description Length

    Directory of Open Access Journals (Sweden)

    John S. Conery

    2008-01-01

    Full Text Available This paper presents a new information theoretic framework for aligning sequences in bioinformatics. A transmitter compresses a set of sequences by constructing a regular expression that describes the regions of similarity in the sequences. To retrieve the original set of sequences, a receiver generates all strings that match the expression. An alignment algorithm uses minimum description length to encode and explore alternative expressions; the expression with the shortest encoding provides the best overall alignment. When two substrings contain letters that are similar according to a substitution matrix, a code length function based on conditional probabilities defined by the matrix will encode the substrings with fewer bits. In one experiment, alignments produced with this new method were found to be comparable to alignments from CLUSTALW. A second experiment measured the accuracy of the new method on pairwise alignments of sequences from the BAliBASE alignment benchmark.

  3. Alignment method for solar collector arrays

    Science.gov (United States)

    Driver, Jr., Richard B

    2012-10-23

    The present invention is directed to an improved method for establishing camera fixture location for aligning mirrors on a solar collector array (SCA) comprising multiple mirror modules. The method aligns the mirrors on a module by comparing the location of the receiver image in photographs with the predicted theoretical receiver image location. To accurately align an entire SCA, a common reference is used for all of the individual module images within the SCA. The improved method can use relative pixel location information in digital photographs along with alignment fixture inclinometer data to calculate relative locations of the fixture between modules. The absolute locations are determined by minimizing alignment asymmetry for the SCA. The method inherently aligns all of the mirrors in an SCA to the receiver, even with receiver position and module-to-module alignment errors.

  4. Multiscale peak alignment for chromatographic datasets.

    Science.gov (United States)

    Zhang, Zhi-Min; Liang, Yi-Zeng; Lu, Hong-Mei; Tan, Bin-Bin; Xu, Xiao-Na; Ferro, Miguel

    2012-02-01

    Chromatography has been extensively applied in many fields, such as metabolomics and quality control of herbal medicines. Preprocessing, especially peak alignment, is a time-consuming task prior to the extraction of useful information from the datasets by chemometrics and statistics. To accurately and rapidly align shift peaks among one-dimensional chromatograms, multiscale peak alignment (MSPA) is presented in this research. Peaks of each chromatogram were detected based on continuous wavelet transform (CWT) and aligned against a reference chromatogram from large to small scale gradually, and the aligning procedure is accelerated by fast Fourier transform cross correlation. The presented method was compared with two widely used alignment methods on chromatographic dataset, which demonstrates that MSPA can preserve the shapes of peaks and has an excellent speed during alignment. Furthermore, MSPA method is robust and not sensitive to noise and baseline. MSPA was implemented and is available at http://code.google.com/p/mspa. PMID:22222564

  5. Natural gas; Erdgas

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Frank [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). DVGW-Forschungsstelle; Groeschl, Frank; Wetzel, Uwe [DVGW, Bonn (Germany); Heikrodt, Klaus [Hochschule Ostwestfalen-Lippe, Lemgo (Germany); Krause, Hartmut [Technische Univ. Bergakademie Freiberg (Germany). DBI Gastechnologisches Institut, An-Institut; Sametschek, Christian; Witschen, Bernhard [Team Consult AM G.P.E. GmbH, Berlin (Germany)

    2013-04-01

    With some delay, the year 2012 has directed the energy-policy debate in Germany on important, fundamental aspects for the energy supply in Germany and thus on the competitiveness of the German economy: How can the costs for the energy policy turnaround be controlled? What are the impacts of the expansions of reserves and resources of petroleum and natural gas by means of the exploration of tight petroleum deposits and shale gas? How can the secure energy supply be guaranteed despite the forced expansion of volatile renewable energy sources? What might be the role of natural gas?.

  6. Pupil Alignment Measuring Technique and Alignment Reference for Instruments or Optical Systems

    Science.gov (United States)

    Hagopian, John G.

    2010-01-01

    A technique was created to measure the pupil alignment of instruments in situ by measuring calibrated pupil alignment references (PARs) in instruments. The PAR can also be measured using an alignment telescope or an imaging system. PAR allows the verification of the science instrument (SI) pupil alignment at the integrated science instrument module (ISIM) level of assembly at ambient and cryogenic operating temperature. This will allow verification of the ISIM+SI alignment, and provide feedback to realign the SI if necessary.

  7. NON-ALIGNEMENT IN AFRICA

    Directory of Open Access Journals (Sweden)

    G. Jacobs

    2012-02-01

    Full Text Available The first indications to the Western world that African non-alignment had achieved conscious political form became apparent only in the late 1940's. This strand of thought within the tapestry of Africanism reached its zenith with the declarations of Kwame Nkrumah, Jomo Kenyatta and Julius Nyerere in the years after the Pan-African Congress in Manchester in 1945. The causes of the movement go back far beyond the first official expressions of an African solidarity in the 1940's. As a mature expression of group attitudes tqwards foreign pol icy, nonalignment can be traced back to the roots of African nationalism.

  8. The Cluster Substructure - Alignment Connection

    CERN Document Server

    Plionis, M

    2002-01-01

    Using the APM cluster data we investigate whether the dynamical status of clusters is related to the large-scale structure of the Universe. We find that cluster substructure is strongly correlated with the tendency of clusters to be aligned with their nearest neighbour and in general with the nearby clusters that belong to the same supercluster. Furthermore, dynamically young clusters are more clustered than the overall cluster population. These are strong indications that cluster develop in a hierarchical fashion by anisotropy merging along the large-scale filamentary superclusters within which they are embedded.

  9. The Substructure-Alignment Connection

    CERN Document Server

    Plionis, M; Plionis, Manolis; Basilakos, Spyros

    2001-01-01

    Using a sample of 903 APM clusters we investigate whether their dynamical status, as evidenced by the presence of significant substructures, is related to the large-scale structure of the Universe. We find that the cluster dynamical activity is strongly correlated with the tendency of clusters to be aligned with their nearest neighbour and in general with the nearby clusters that belong to the same supercluster. Furthermore, dynamically active clusters are more clustered than the overall cluster population. These are strong indications that clusters develop in a hierarchical fashion by anisotropic merging along the large-scale filaments within which they are embedded.

  10. Strategies for active alignment of lenses

    Science.gov (United States)

    Langehanenberg, Patrik; Heinisch, Josef; Wilde, Chrisitan; Hahne, Felix; Lüerß, Bernd

    2015-10-01

    Today's optical systems require up-to-date assembly and joining technology. The trend of keeping dimensions as small as possible while maintaining or increasing optical imaging performance leaves little to no room for mechanical lens adjustment equipment that may remain in the final product. In this context active alignment of optical elements opens up possibilities for the fast and cost-economic manufacturing of lenses and lens assemblies with highest optical performance. Active alignment for lens manufacturing is the precise alignment of the optical axis of a lens with respect to an optical or mechanical reference axis (e.g. housing) including subsequent fixation by glue. In this contribution we will describe different approaches for active alignment and outline strengths and limitations of the different methods. Using the SmartAlign principle, highest quality cemented lenses can be manufactured without the need for high precision prealignment, while the reduction to a single alignment step greatly reduces the cycle time. The same strategies can also be applied to bonding processes. Lenses and lens groups can be aligned to both mechanical and optical axes to maximize the optical performance of a given assembly. In hybrid assemblies using both mechanical tolerances and active alignment, SmartAlign can be used to align critical lens elements anywhere inside the system for optimized total performance. Since all geometrical parameters are re-measured before each alignment, this process is especially suited for complex and time-consuming production processes where the stability of the reference axis would otherwise be critical. For highest performance, lenses can be actively aligned using up to five degrees of freedom. In this way, SmartAlign enables the production of ultra-precise mounted lenses with an alignment precision below 1 μm.

  11. Ischemic preconditioning enhances integrity of coronary endothelial tight junctions

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhao [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States); Jin, Zhu-Qiu, E-mail: zhu-qiu.jin@sdstate.edu [Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, SD 57007 (United States)

    2012-08-31

    Highlights: Black-Right-Pointing-Pointer Cardiac tight junctions are present between coronary endothelial cells. Black-Right-Pointing-Pointer Ischemic preconditioning preserves the structural and functional integrity of tight junctions. Black-Right-Pointing-Pointer Myocardial edema is prevented in hearts subjected to ischemic preconditioning. Black-Right-Pointing-Pointer Ischemic preconditioning enhances translocation of ZO-2 from cytosol to cytoskeleton. -- Abstract: Ischemic preconditioning (IPC) is one of the most effective procedures known to protect hearts against ischemia/reperfusion (IR) injury. Tight junction (TJ) barriers occur between coronary endothelial cells. TJs provide barrier function to maintain the homeostasis of the inner environment of tissues. However, the effect of IPC on the structure and function of cardiac TJs remains unknown. We tested the hypothesis that myocardial IR injury ruptures the structure of TJs and impairs endothelial permeability whereas IPC preserves the structural and functional integrity of TJs in the blood-heart barrier. Langendorff hearts from C57BL/6J mice were prepared and perfused with Krebs-Henseleit buffer. Cardiac function, creatine kinase release, and myocardial edema were measured. Cardiac TJ function was evaluated by measuring Evans blue-conjugated albumin (EBA) content in the extravascular compartment of hearts. Expression and translocation of zonula occludens (ZO)-2 in IR and IPC hearts were detected with Western blot. A subset of hearts was processed for the observation of ultra-structure of cardiac TJs with transmission electron microscopy. There were clear TJs between coronary endothelial cells of mouse hearts. IR caused the collapse of TJs whereas IPC sustained the structure of TJs. IR increased extravascular EBA content in the heart and myocardial edema but decreased the expression of ZO-2 in the cytoskeleton. IPC maintained the structure of TJs. Cardiac EBA content and edema were reduced in IPC hearts. IPC

  12. Natural Gas Monthly, October 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-10

    The (NGM) Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. This month`s feature articles are: US Production of Natural Gas from Tight Reservoirs: and Expanding Rule of Underground Storage.

  13. A tightly coupled non-equilibrium model for inductively coupled radio-frequency plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Munafò, A., E-mail: munafo@illinois.edu; Alfuhaid, S. A., E-mail: alfuhai2@illinois.edu; Panesi, M., E-mail: mpanesi@illinois.edu [Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, Talbot Laboratory, 104 S. Wright St., Urbana, Illinois 61801 (United States); Cambier, J.-L., E-mail: jean-luc.cambier@us.af.mil [Edwards Air Force Base Research Laboratory, 10 E. Saturn Blvd., Edwards AFB, California 93524 (United States)

    2015-10-07

    The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients.

  14. Absorption-limited and phase-matched high harmonic generation in the tight focusing regime

    International Nuclear Information System (INIS)

    High harmonic generation (HHG) at a high repetition rate requires tight focusing of the moderate peak power driving pulses. So far the conversion efficiencies that have been achieved in this regime are orders of magnitude behind the values that have been demonstrated with loose focusing of high energy (high peak power) lasers. In this contribution, we discuss the scaling laws for the main physical quantities of HHG and in particular analyze the limiting effects: dephasing, absorption and plasma defocusing. It turns out that phase-matched and absorption-limited HHG can be achieved even for very small focal spot sizes using a target gas provided with an adequately high density. Experimentally, we investigate HHG in a gas jet of argon, krypton and xenon. By analyzing the pressure dependence we are able to disentangle the dephasing and absorption effects and prove that the generated high order harmonics are phase-matched and absorption-limited. The obtained conversion efficiency is as high as 8 × 10−6 for the 17th harmonic generated in xenon and 1.4 × 10−6 for the 27th harmonic generated in argon. Our findings pave the way for highly efficient harmonic generation at megahertz repetition rates. (papers)

  15. A tightly coupled non-equilibrium model for inductively coupled radio-frequency plasmas

    International Nuclear Information System (INIS)

    The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients

  16. Galaxy alignment on large and small scales

    Science.gov (United States)

    Kang, X.; Lin, W. P.; Dong, X.; Wang, Y. O.; Dutton, A.; Macciò, A.

    2016-10-01

    Galaxies are not randomly distributed across the universe but showing different kinds of alignment on different scales. On small scales satellite galaxies have a tendency to distribute along the major axis of the central galaxy, with dependence on galaxy properties that both red satellites and centrals have stronger alignment than their blue counterparts. On large scales, it is found that the major axes of Luminous Red Galaxies (LRGs) have correlation up to 30Mpc/h. Using hydro-dynamical simulation with star formation, we investigate the origin of galaxy alignment on different scales. It is found that most red satellite galaxies stay in the inner region of dark matter halo inside which the shape of central galaxy is well aligned with the dark matter distribution. Red centrals have stronger alignment than blue ones as they live in massive haloes and the central galaxy-halo alignment increases with halo mass. On large scales, the alignment of LRGs is also from the galaxy-halo shape correlation, but with some extent of mis-alignment. The massive haloes have stronger alignment than haloes in filament which connect massive haloes. This is contrary to the naive expectation that cosmic filament is the cause of halo alignment.

  17. Tight-binding lattices with an oscillating imaginary gauge field

    Science.gov (United States)

    Longhi, Stefano

    2016-08-01

    We consider non-Hermitian dynamics of a quantum particle hopping on a one-dimensional tight-binding lattice made of N sites with asymmetric hopping rates induced by a time-periodic oscillating imaginary gauge field. A deeply different behavior is found depending on the lattice topology. While in a linear chain (open boundary conditions) an oscillating field can lead to a complex quasienergy spectrum via a multiple parametric resonance; in a ring topology (Born-von Karman periodic boundary conditions) an entirely real quasienergy spectrum can be found and the dynamics is pseudo-Hermitian. In the large-N limit, parametric instability and pseudo-Hermitian dynamics in the two different lattice topologies are physically explained on the basis of a simple picture of wave-packet propagation.

  18. Tight focusing of femtosecond elliptically polarised vortex light pulses

    International Nuclear Information System (INIS)

    This paper studies the tight focusing properties of femtosecond elliptically polarised vortex light pulses. Based on Richards—Wolf vectorial diffraction integral, the expressions for the electric field, the velocity of the femtosecond light pulse and the total angular momentum of focused pluses are derived. The numerical calculations are also given to illustrate the intensity distribution, phase contour, the group velocity variation and the total angular momentum near the focus. It finds that near the focus the femtosecond elliptically polarised vortex light pulse can travel at various group speeds, that is, slower or faster than light speed in vacuum, depending on the numerical aperture of the focusing objective system. Moreover, it also studies the influence of the numerical aperture of the focusing objective and the time duration of the elliptically polarised vortex light pulse on the total angular momentum distribution in the focused field. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  19. Tight focusing of femtosecond elliptically polarised vortex light pulses

    Institute of Scientific and Technical Information of China (English)

    Hua Li-Min; Chen Bao-Suan; Chen Zi-Yang; Pu Ji-Xiong

    2011-01-01

    This paper studies the tight focusing properties of femtosecond elliptically polarised vortex light pulses. Based on Richards-Wolf vectorial diffraction integral, the expressions for the electric field, the velocity of the femtosecond light pulse and the total angular momentum of focused pluses are derived. The numerical calculations are also given to illustrate the intensity distribution, phase contour, the group velocity variation and the total angular momentum near the focus. It finds that near the focus the femtosecond elliptically polarised vortex light pulse can travel at various group speeds, that is, slower or faster than light speed in vacuum, depending on the numerical aperture of the focusing objective system. Moreover, it also studies the influence of the numerical aperture of the focusing objective and the time duration of the elliptically polarised vortex light pulse on the total angular momentum distribution in the focused field.

  20. Propagation equation for tight-focusing by a parabolic mirror.

    Science.gov (United States)

    Couairon, A; Kosareva, O G; Panov, N A; Shipilo, D E; Andreeva, V A; Jukna, V; Nesa, F

    2015-11-30

    Part of the chain in petawatt laser systems may involve extreme focusing conditions for which nonparaxial and vectorial effects have high impact on the propagation of radiation. We investigate the possibility of using propagation equations to simulate numerically the focal spot under these conditions. We derive a unidirectional propagation equation for the Hertz vector, describing linear and nonlinear propagation under situations where nonparaxial diffraction and vectorial effects become significant. By comparing our simulations to the results of vector diffraction integrals in the case of linear tight-focusing by a parabolic mirror, we establish a practical criterion for the critical f -number below which initializing a propagation equation with a parabolic input phase becomes inaccurate. We propose a method to find suitable input conditions for propagation equations beyond this limit. Extreme focusing conditions are shown to be modeled accurately by means of numerical simulations of the unidirectional Hertz-vector propagation equation initialized with suitable input conditions.

  1. S0 Tight Loop Studies on ICHIRO 9-Cell Cavities

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Fumio [KEK; Konomi, T. [KEK; Saito, Kenji [KEK; Bice, Damon [Fermilab; Crawford, Anthony C. [JLAB; Geng, Rongli [JLAB

    2009-11-01

    We have continued high gradient R&D of ICHIRO 9-cell cavities at KEK. ICHIRO 9-cell cavity #5 (I9#5) that has no end groups on beam tube to focus on high gradient sent to Jlab as S0 tight loop study. Surface treatments and vertical test were repeated 3 times at Jlab, and then I9#5 sent back to KEK. We also repeated surface treatments and test at KEK. Maximum gradients were 36.5MV/m at Jlab, and 33.7MV/m at KEK so far. Now we are struggling with the puzzle why the results of singles do not work well on 9-cell cavities.

  2. An efficient LDA+U based tight binding approach.

    Science.gov (United States)

    Sanna, Simone; Hourahine, B; Gallauner, Th; Frauenheim, Th

    2007-07-01

    The functionals usually applied in DFT calculations have deficiencies in describing systems with strongly localized electrons such as transition metals or rare earth (RE) compounds. In this work, we present the self-consistent charge density based functional tight binding (SCC-DFTB) calculation scheme including LDA+U like potentials and apply it for the simulation of RE-doped GaN. DFTB parameters for the simulation of GaN and a selection of rare earth ions, where the f electrons were explicitly included in the valence, have been created. The results of the simulations were tested against experimental data (where present) and against various more sophisticated but computationally more costly DFT calculations. Our approach is found to correctly reproduce the geometry and the energetic of the studied systems.

  3. Critical heat flux in tubes and tight hexagonal rod lattices

    International Nuclear Information System (INIS)

    The critical heat flux (CHF) in small-diameter tubes and in tight hexagonal 7-rod and 37-rod bundles was investigated in the KRISTA test facility, using Freon 12 as the working fluid. The measurements in tubes showed that the influence of the tube diameter on CHF cannot be described as suggested by earlier publications with sufficient accuracy. CHF in bundles is lower than in tubes under comparable conditions. The influence of spacers (grid spacers, wire wraps) on CHF was found to be governed by local steam qualities. A comparison of the test results with some CHF prediction methods showed that the look-up table method reproduces the test results in circular tubes most accurately. Combined with CHF look-up tables, subchannel analysis and Ahmad's fluid-to-fluid scaling law, Freon experiments have proven to be a suitable tool for CHF prediction in water-cooled rod bundles. (orig.)

  4. Tight-binding parameters for charge transfer along DNA

    CERN Document Server

    Hawke, L G D; Simserides, C

    2009-01-01

    We systematically examine all the tight-binding parameters pertinent to charge transfer along DNA. The $\\pi$ molecular structure of the four DNA bases (adenine, thymine, cytosine, and guanine) is investigated by using the linear combination of atomic orbitals method with a recently introduced parametrization. The HOMO and LUMO wavefunctions and energies of DNA bases are discussed and then used for calculating the corresponding wavefunctions of the two B-DNA base-pairs (adenine-thymine and guanine-cytosine). The obtained HOMO and LUMO energies of the bases are in good agreement with available experimental values. Our results are then used for estimating the complete set of charge transfer parameters between neighboring bases and also between successive base-pairs, considering all possible combinations between them, for both electrons and holes. The calculated microscopic quantities can be used in mesoscopic theoretical models of electron or hole transfer along the DNA double helix, as they provide the necessar...

  5. Experiments on Exhaust Noise of Tightly Integrated Propulsion Systems

    Science.gov (United States)

    Bridges, James E.; Brown, Clifford A.; Bozak, Richard F.

    2014-01-01

    A wide-ranging series of tests have been completed that seek to map the effects of installation, including jet by jet interaction effects, on exhaust noise from various nozzles in forward flight. The primary data was far-field acoustic spectral directivity. The goals of the test series were (i) to generate enough data for empirical models of the different effects, and (ii) to provide data for advanced computational noise predictions methods applied to simplified yet realistic configurations. Data is presented that demonstrate several checks on data quality and that provide an overview of trends observed to date. Among the findings presented here: (i) Data was repeatable between jet rigs for single nozzles with and without surfaces to within +/- 0.5 dB. (ii) The presence of a second jet caused a strong reduction of the summed noise in the plane of the two plumes and an increase over the expected source doubling in most other azimuthal planes. (iii) The impact of the second jet was reduced when the jets were unheated. (iv) The impact of adding a second isolated rectangular jet was relatively independent of the nozzle aspect ratio up to aspect ratio 8:1. (v) Forward flight had similar impact on a high aspect ratio (8:1) jet as on an axisymmetric jet, except at the peak noise angle where the impact was less. (vi) The effect of adding a second round jet to a tightly integrated nozzle where the nozzle lip was less than a diameter from the surface was very dependent upon the length of the surface downstream of the nozzle. (vii) When the nozzles were rectangular and tightly integrated with the airframe surface the impact of a second jet was very dependent upon how close together the two jets were. This paper serves as an overview of the test; other papers presented in the same conference will give more detailed analysis of the results.

  6. Tightly coupled low cost 3D RISS/GPS integration using a mixture particle filter for vehicular navigation.

    Science.gov (United States)

    Georgy, Jacques; Noureldin, Aboelmagd

    2011-01-01

    Satellite navigation systems such as the global positioning system (GPS) are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS)-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF). Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF) was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D) reduced inertial sensors system (RISS) with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle's odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s) even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift, which are

  7. Tightly Coupled Low Cost 3D RISS/GPS Integration Using a Mixture Particle Filter for Vehicular Navigation

    Directory of Open Access Journals (Sweden)

    Jacques Georgy

    2011-04-01

    Full Text Available Satellite navigation systems such as the global positioning system (GPS are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF. Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D reduced inertial sensors system (RISS with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle’s odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift

  8. Galaxy alignments: Observations and impact on cosmology

    CERN Document Server

    Kirk, Donnacha; Hoekstra, Henk; Joachimi, Benjamin; Kitching, Thomas D; Mandelbaum, Rachel; Sifón, Cristóbal; Cacciato, Marcello; Choi, Ami; Kiessling, Alina; Leonard, Adrienne; Rassat, Anais; Schäfer, Björn Malte

    2015-01-01

    Galaxy shapes are not randomly oriented, rather they are statistically aligned in a way that can depend on formation environment, history and galaxy type. Studying the alignment of galaxies can therefore deliver important information about the astrophysics of galaxy formation and evolution as well as the growth of structure in the Universe. In this review paper we summarise key measurements of intrinsic alignments, divided by galaxy type, scale and environment. We also cover the statistics and formalism necessary to understand the observations in the literature. With the emergence of weak gravitational lensing as a precision probe of cosmology, galaxy alignments took on an added importance because they can mimic cosmic shear, the effect of gravitational lensing by large-scale structure on observed galaxy shapes. This makes intrinsic alignments an important systematic effect in weak lensing studies. We quantify the impact of intrinsic alignments on cosmic shear surveys and finish by reviewing practical mitigat...

  9. Comparative genomics beyond sequence-based alignments

    DEFF Research Database (Denmark)

    Þórarinsson, Elfar; Yao, Zizhen; Wiklund, Eric D.;

    2008-01-01

    Recent computational scans for non-coding RNAs (ncRNAs) in multiple organisms have relied on existing multiple sequence alignments. However, as sequence similarity drops, a key signal of RNA structure--frequent compensating base changes--is increasingly likely to cause sequence-based alignment...... methods to misalign, or even refuse to align, homologous ncRNAs, consequently obscuring that structural signal. We have used CMfinder, a structure-oriented local alignment tool, to search the ENCODE regions of vertebrate multiple alignments. In agreement with other studies, we find a large number...... of potential RNA structures in the ENCODE regions. We report 6587 candidate regions with an estimated false-positive rate of 50%. More intriguingly, many of these candidates may be better represented by alignments taking the RNA secondary structure into account than those based on primary sequence alone, often...

  10. Enhanced recovery of unconventional gas. The methodology--Volume III (of 3 volumes)

    Energy Technology Data Exchange (ETDEWEB)

    Kuuskraa, V. A.; Brashear, J. P.; Doscher, T. M.; Elkins, L. E.

    1979-02-01

    The methodology is described in chapters on the analytic approach, estimated natural gas production, recovery from tight gas sands, recovery from Devonian shales, recovery from coal seams, and recovery from geopressured aquifers. (JRD)

  11. Scintillation counter: photomultiplier tube alignment

    International Nuclear Information System (INIS)

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into the sample receiving zone. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (auth)

  12. Recursions for Statistical Multiple Alignment

    DEFF Research Database (Denmark)

    Hein, Jotun; Pedersen, Christian Nørgaard Storm; Jensen, Jens Ledet

    2002-01-01

    Algorithms are presented that allow the calculation of the probability of a set of sequences related by a binary tree that have evolved according to the Thorne–Kishino–Felsenstein model for a fixed set of parameters. The algorithms are based on a Markov chain generating sequences and their alignm...... but probabilistically different. The running time of the algorithms is , where Li is the length of the ith observed sequences and d is the number of sequences. An alternative recursion is also formulated that uses only a Markov chain involving the inner nodes of a tree....... and their alignment at nodes in a tree. Depending on whether the complete realization of this Markov chain is decomposed into the first transition and the rest of the realization or the last transition and the first part of the realization, two kinds of recursions are obtained that are computationally similar...

  13. Fiscal State-Citizen Alignment

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    2016-01-01

    to the 2008 crisis and the larger post-1970s politico-economic constellation. The crisis can be perceived as a particular articulation of an age-old state-household dynamic—a dialectical alignment of the mode of fiscal state-crafting with the ethos of the state-citizen nexus—characterized by a heightened......The 2008 crisis ended the growth bubble of the 2000s, which Organisation for Economic Co-operation and Development (OECD) governments facilitated through the normative/political-regulatory promotion of household indebtedness. Historically contextualizing this state-citizen relationship......, this article maps out four episodes of sovereign fiscalism, namely, debt-taking in the Italian city-states, the making of the absolutist tax/fiscal state, the eighteenth/nineteenth century elaboration of the economic citizen, and the postwar era of managed capitalism. Finally, it applies this framework...

  14. Using Student Reflections to Explore Curriculum Alignment

    OpenAIRE

    Marina Harvey; Chris Baumann

    2012-01-01

    The concept of curriculum alignment is held as a guiding principle of good curriculum design in higher education. Curriculum alignment can be mapped using a variety of strategies and tools. This paper reports on a project that expands the horizons of curriculum review by applying a novel methodology, word clouds, to investigate the use of student reflections for exploring curriculum alignment.Students, from Australia and Denmark, engaged in written reflections about their learning in a Busine...

  15. Measurement of alignment between standards and assessment

    OpenAIRE

    Näsström, Gunilla

    2008-01-01

    Many educational systems of today are standards-based and aim at for alignment, i.e. consistency, among the components of the educational system: standards, teaching and assessment. To conclude whether the alignment is sufficiently high, analyses with a useful model are needed. This thesis investigates the usefulness of models for analyzing alignment between standards and assessments, with emphasis on one method: Bloom’s revised taxonomy. The thesis comprises an introduction and five articles...

  16. FUSE: Multiple Network Alignment via Data Fusion

    OpenAIRE

    Gligorijević, Vladimir; Malod-Dognin, Noël; Pržulj, Nataša

    2014-01-01

    Discovering patterns in networks of protein-protein interactions (PPIs) is a central problem in systems biology. Alignments between these networks aid functional understanding as they uncover important information, such as evolutionary conserved pathways, protein complexes and functional orthologs. The objective of a multiple network alignment is to create clusters of nodes that are evolutionarily conserved and functionally consistent across all networks. Unfortunately, the alignment methods ...

  17. Alignment performance monitoring for ASML systems

    Science.gov (United States)

    Chung, Woong-Jae; Temchenko, Vlad; Hauck, Tarja; Schmidt, Sebastian

    2006-03-01

    In today's semiconductor industry downscaling of the IC design puts a stringent requirement on pattern overlay control. Tighter overlay requirements lead to exceedingly higher rework rates, meaning additional costs to manufacturing. Better alignment control became a target of engineering efforts to decrease rework rate for high-end technologies. Overlay performance is influenced by known parameters such as "Shift, Scaling, Rotation, etc", and unknown parameters defined as "Process Induced Variation", which are difficult to control by means of a process automation system. In reality, this process-induced variation leads to a strong wafer to wafer, or lot to lot variation, which are not easy to detect in the mass-production environment which uses sampling overlay measurements for only several wafers in a lot. An engineering task of finding and correcting a root cause for Process Induced Variations of overlay performance will be greatly simplified if the unknown parameters could be tracked for each wafer. This paper introduces an alignment performance monitoring method based on analysis of automatically generated "AWE" files for ASML scanner systems. Because "AWE" files include alignment results for each aligned wafer, it is possible to use them for monitoring, controlling and correcting the causes of "process induced" overlay performance without requiring extra measurement time. Since "AWE" files include alignment information for different alignment marks, it is also possible to select and optimize the best alignment recipe for each alignment strategy. Several case studies provided in our paper will demonstrate how AWE file analysis can be used to assist engineer in interpreting pattern alignment data. Since implementing our alignment data monitoring method, we were able to achieve significant improvement of alignment and overlay performance without additional overlay measurement time. We also noticed that the rework rate coming from alignment went down and

  18. COS to FGS Alignment {NUV}

    Science.gov (United States)

    Hartig, George

    2009-07-01

    DESCRIPTION: In order to determine the location of the COS reference frame with respect to the FGS reference frames, NUV MIRRORA images will be obtained of an astrometric target and field. Astrometric guide stars and targets must be employed for this activity in order to facilitate the alignment wth the FGS. Images will be obtained at the initial pointing and at positions offset in V2 and in V3. Starting with the original blind pointing, obtain MIRRORA image exposures in a 5x5 POS-TARG grid centered on initial pointing; repeat the image sequence at two bracketing focus positions in same visit. Following completion of third pattern, return to nominal focus and perform 5x5 ACQ/SEARCH target acquisition and obtain one TIME-TAG MIRRORA image and one ACCUM verification exposure. Next perform an ACQ/IMAGE target acquisition followed by an ACCUM verification exposure. Also obtain ACCUM verification exposure for each of the two alternate focus positions used previously. Using MIRRORB obtain ACCUM confirmation image at nominal focus and ACCUM images at alternate focus positions and then perform an ACQ/IMAGE and confirming image at nominal focus. Analyze imagery, uplink pointing offset as offset 11469A and adjust nominal focus via patchable constant uplinked with subsequent visit of this program; update aperture locations via modified SIAF file uplinked with subsequent SMS. Use updated focus and offset pointing as input for COS 09 {program 11469 - NUV Optics Alignment and Focus} {note the SIAF update is not a prerequisite for COS 09 to proceed, but the pointing offset and focus update are}.

  19. PACMAN study of FSI and micro-triangulation for the pre-alignment of CLIC

    CERN Document Server

    Kamugasa, William Solomon

    2015-01-01

    The alignment precision of linear colliders is extremely demanding owing to the very narrow beam size at the interaction point. Unlike circular colliders, particles in linear colliders have only one chance to collide and are hence tightly focused to maximise the number of interactions per collision. The PACMAN* project is dedicated to study the integration of both fiducialization and alignment of the components on a common support. FSI (Frequency Scanning Interferometry) and Micro-triangulation will contribute to this goal. FSI realized by Etalon AG’s Absolute Multiline system and Micro-triangulation implemented by QDaedalus system developed at ETH Zurich offer precision of 0.5 μm/m and 2.4 μm/m respectively. However, these systems need to be improved in order to provide the necessary geometric information via distance measurements (multilateration) and angle measurements (triangulation), respectively. The paper describes the current status and the future developments of Absolute Multiline and QDaedalus, ...

  20. Track Based Alignment of Composite Detector Structures

    CERN Document Server

    Karimäki, V; Schilling, F P

    2006-01-01

    An iterative algorithm for track based alignment is presented. The algorithm can be applied to rigid composite detector structures or to individual modules. The iterative process involves track reconstruction and alignment, in which the chi-2 function of the hit residuals of each alignable object is minimized. Six alignment parameters per structure or per module, three for location and three for orientation, can be computed. The method is computationally light and easily parallelizable. The performance of the method is demonstrated with simulated tracks in the CMS pixel detector and tracks reconstructed from experimental data recorded with a test beam setup.

  1. Molecular alignment using circularly polarized laser pulses

    CERN Document Server

    Smeenk, C T L

    2013-01-01

    We show that circularly polarized femtosecond laser pulses produce field-free alignment in linear and planar molecules. We study the rotational wavepacket evolution of O$_2$ and benzene created by circularly polarized light. For benzene, we align the molecular plane to the plane of polarization. For O$_2$, we demonstrate that circular polarization yields a net alignment along the laser propagation axis at certain phases of the evolution. Circular polarization gives us the ability to control alignment of linear molecules outside the plane of polarization, providing new capabilities for molecular imaging.

  2. The twilight zone of cis element alignments.

    Science.gov (United States)

    Sebastian, Alvaro; Contreras-Moreira, Bruno

    2013-02-01

    Sequence alignment of proteins and nucleic acids is a routine task in bioinformatics. Although the comparison of complete peptides, genes or genomes can be undertaken with a great variety of tools, the alignment of short DNA sequences and motifs entails pitfalls that have not been fully addressed yet. Here we confront the structural superposition of transcription factors with the sequence alignment of their recognized cis elements. Our goals are (i) to test TFcompare (http://floresta.eead.csic.es/tfcompare), a structural alignment method for protein-DNA complexes; (ii) to benchmark the pairwise alignment of regulatory elements; (iii) to define the confidence limits and the twilight zone of such alignments and (iv) to evaluate the relevance of these thresholds with elements obtained experimentally. We find that the structure of cis elements and protein-DNA interfaces is significantly more conserved than their sequence and measures how this correlates with alignment errors when only sequence information is considered. Our results confirm that DNA motifs in the form of matrices produce better alignments than individual sequences. Finally, we report that empirical and theoretically derived twilight thresholds are useful for estimating the natural plasticity of regulatory sequences, and hence for filtering out unreliable alignments.

  3. IMAGA: INTRON MULTIPLE ALIGNMENT USING GENETIC ALGORITHM

    Directory of Open Access Journals (Sweden)

    V. AMOUDA,

    2010-11-01

    Full Text Available Multiple sequence alignment (MSA is one of the multi-dimensional problems in biology. This paper describes a new approach to solve MSA, a NP-hard problem using modified Genetic Algorithm with new mutation operator. A web based tool iMAGA (Intron Multiple Alignment using Genetic Algorithm is developed for aligning the intron sequences in order to find the pattern. It has two modules (i iExtractor/ iClassifier which extracts and classifies introns (ii iAligner/ Pattern Finder which aligns the intron sequences and finds the patterns. iAligner, the core module of the tool aligns any type of sequences (DNA, RNA, Protein & Intron. In this module GA is applied in which the chromosome consists of gap positions. On applying conventional mutation operator leads to problems like repetition and increase in number of gap positions. To overcome theseproblems, a newly designed mutation operator X-Shuffler is proposed.To validate the alignment, the sum-of-pairs score is used to compare iMAGA with widely used tools. The data sets chosen from the standard BaliBASE, SMART and OXBENCH benchmark alignment suite. To validate the pattern obtained using iMAGA tool, the similarity percentage of the pattern is compared with MEME, a widely used motif finder. Dataset of Saccharomyces Cerviceae with 254 intron sequences are used to prove this work. The tool is available at www.imaga.bicpu.edu.in.

  4. Triangular Alignment (TAME). A Tensor-based Approach for Higher-order Network Alignment

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, Shahin [Purdue Univ., West Lafayette, IN (United States); Gleich, David F. [Purdue Univ., West Lafayette, IN (United States); Kolda, Tamara G. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Grama, Ananth [Purdue Univ., West Lafayette, IN (United States)

    2015-11-01

    Network alignment is an important tool with extensive applications in comparative interactomics. Traditional approaches aim to simultaneously maximize the number of conserved edges and the underlying similarity of aligned entities. We propose a novel formulation of the network alignment problem that extends topological similarity to higher-order structures and provide a new objective function that maximizes the number of aligned substructures. This objective function corresponds to an integer programming problem, which is NP-hard. Consequently, we approximate this objective function as a surrogate function whose maximization results in a tensor eigenvalue problem. Based on this formulation, we present an algorithm called Triangular AlignMEnt (TAME), which attempts to maximize the number of aligned triangles across networks. We focus on alignment of triangles because of their enrichment in complex networks; however, our formulation and resulting algorithms can be applied to general motifs. Using a case study on the NAPABench dataset, we show that TAME is capable of producing alignments with up to 99% accuracy in terms of aligned nodes. We further evaluate our method by aligning yeast and human interactomes. Our results indicate that TAME outperforms the state-of-art alignment methods both in terms of biological and topological quality of the alignments.

  5. A confocal microscope position sensor for micron-scale target alignment in ultra-intense laser-matter experiments.

    Science.gov (United States)

    Willis, Christopher; Poole, Patrick L; Akli, Kramer U; Schumacher, Douglass W; Freeman, Richard R

    2015-05-01

    A diagnostic tool for precise alignment of targets in laser-matter interactions based on confocal microscopy is presented. This device permits precision alignment of targets within the Rayleigh range of tight focusing geometries for a wide variety of target surface morphologies. This confocal high-intensity positioner achieves micron-scale target alignment by selectively accepting light reflected from a narrow range of target focal planes. Additionally, the design of the device is such that its footprint and sensitivity can be tuned for the desired chamber and experiment. The device has been demonstrated to position targets repeatably within the Rayleigh range of the Scarlet laser system at The Ohio State University, where use of the device has provided a marked increase in ion yield and maximum energy.

  6. Bayesian coestimation of phylogeny and sequence alignment

    Directory of Open Access Journals (Sweden)

    Jensen Jens

    2005-04-01

    Full Text Available Abstract Background Two central problems in computational biology are the determination of the alignment and phylogeny of a set of biological sequences. The traditional approach to this problem is to first build a multiple alignment of these sequences, followed by a phylogenetic reconstruction step based on this multiple alignment. However, alignment and phylogenetic inference are fundamentally interdependent, and ignoring this fact leads to biased and overconfident estimations. Whether the main interest be in sequence alignment or phylogeny, a major goal of computational biology is the co-estimation of both. Results We developed a fully Bayesian Markov chain Monte Carlo method for coestimating phylogeny and sequence alignment, under the Thorne-Kishino-Felsenstein model of substitution and single nucleotide insertion-deletion (indel events. In our earlier work, we introduced a novel and efficient algorithm, termed the "indel peeling algorithm", which includes indels as phylogenetically informative evolutionary events, and resembles Felsenstein's peeling algorithm for substitutions on a phylogenetic tree. For a fixed alignment, our extension analytically integrates out both substitution and indel events within a proper statistical model, without the need for data augmentation at internal tree nodes, allowing for efficient sampling of tree topologies and edge lengths. To additionally sample multiple alignments, we here introduce an efficient partial Metropolized independence sampler for alignments, and combine these two algorithms into a fully Bayesian co-estimation procedure for the alignment and phylogeny problem. Our approach results in estimates for the posterior distribution of evolutionary rate parameters, for the maximum a-posteriori (MAP phylogenetic tree, and for the posterior decoding alignment. Estimates for the evolutionary tree and multiple alignment are augmented with confidence estimates for each node height and alignment column

  7. Alignments between galaxies, satellite systems and haloes

    Science.gov (United States)

    Shao, Shi; Cautun, Marius; Frenk, Carlos S.; Gao, Liang; Crain, Robert A.; Schaller, Matthieu; Schaye, Joop; Theuns, Tom

    2016-08-01

    The spatial distribution of the satellite populations of the Milky Way and Andromeda are puzzling in that they are nearly perpendicular to the discs of their central galaxies. To understand the origin of such configurations we study the alignment of the central galaxy, satellite system and dark matter halo in the largest of the `Evolution and Assembly of GaLaxies and their Environments' (EAGLE) simulation. We find that centrals and their satellite systems tend to be well aligned with their haloes, with a median misalignment angle of 33° in both cases. While the centrals are better aligned with the inner 10 kpc halo, the satellite systems are better aligned with the entire halo indicating that satellites preferentially trace the outer halo. The central-satellite alignment is weak (median misalignment angle of 52°) and we find that around 20 per cent of systems have a misalignment angle larger than 78°, which is the value for the Milky Way. The central-satellite alignment is a consequence of the tendency of both components to align with the dark matter halo. As a consequence, when the central is parallel to the satellite system, it also tends to be parallel to the halo. In contrast, if the central is perpendicular to the satellite system, as in the case of the Milky Way and Andromeda, then the central-halo alignment is much weaker. Dispersion-dominated (spheroidal) centrals have a stronger alignment with both their halo and their satellites than rotation-dominated (disc) centrals. We also found that the halo, the central galaxy and the satellite system tend to be aligned with the surrounding large-scale distribution of matter, with the halo being the better aligned of the three.

  8. Numerical investigation and optimization of multiple fractures in tight gas reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Hou, M.Z. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE; Energie-Forschungszentrum Niedersachsen, Goslar (Germany); Zhou, L. [Energie-Forschungszentrum Niedersachsen, Goslar (Germany)

    2013-08-01

    The main objective of the project DGMK-680 in phase 2 was to investigate the influence of fractures on each other in a multi-fracture system including their space optimization by using the numerical program FLAC3D with our own developments, which treats all fractures in one 3D geometric model under 3D stress state with fully hydro-mechanical coupling effect. The case study was conducted on a horizontal wellbore at location A, which was stimulated hydraulically with a total of eight transverse fractures in summer 2009. Transverse multiple fractures were simulated using the modified continuum method. In the simulation all fractures were generated in one single model, comprising 22 different rock layers. Each layer was assumed to be homogeneous with regard to its rock and hydromechanical parameters. Thus the influence of the individual fractures on each other can be investigated. The simulation procedure applied, which is a consecutive execution ofa hydraulic and a mechanical computation, is the same for all fractures. The only differences are the primary in-situ stresses, the initial pore pressure, the injection parameters (location, rate, volume, duration), which lead to different patterns of fracture propagations. But there are still some common points, such as irregular patterns of the fracture front, which represents the heterogeneity of the model. All fractures (1 to 8) have their fracture average half-length between 70 m to 115 m, height between 93 m to 114 m and average width between 18 mm to 31 mm. The percentage difference of fracture height for individual fractures is obviously smaller than that of the fracture half-lengths, because the fracture barriers at bottom and top limit the fracture propagation in z-direction. Incomparison with the analytical simulator (FracPro) most results match well. Simulation of multiple fractures at location A, with the newly developed algorithms, shows that individual transverse multiple fractures at distances between 100 -150 m will certain influence on each other in terms of the stress change, but not pore pressure. Generally, this influence as simulated at this location has a positive effect on the fracture geometry as well, and may lead to a bigger half-length and a smaller width of the fracture. In order to maximize the production rate in this specific site, transverse multiple fractures with an optimal fracture distance of ca. 57 m should be implemented. This optimal fracture spacing is derived from the counter of 5 direction change of the primary maximum horizontal stress, to ensure that only transverse fractures are generated in this location. However, the influence on longitudinal multiple fractures is very obvious, as observed from the numerical simulations of longitudinal multiple fractures at U2. Under the circumstances, it is recommended that the boreholes should not be drilled exactly in the direction of maximal horizontal stress ({+-}15 ), in order to avoid the overlapping of fractures. (orig.)

  9. Simulating field-aligned diffusion of a cosmic ray gas

    OpenAIRE

    Snodin, A. P.; Brandenburg, Axel; Mee, A. J.; Shukurov, Anvar

    2005-01-01

    The macroscopic behaviour of cosmic rays in turbulent magnetic fields is discussed. An implementation of anisotropic diffusion of cosmic rays with respect to the magnetic field in a non-conservative, high-order, finite-difference magnetohydrodynamic code is discussed. It is shown that the standard implementation fails near singular X-points of the magnetic field, which are common if the field is random. A modification to the diffusion model for cosmic rays is described and the resulting teleg...

  10. Claudin-21 Has a Paracellular Channel Role at Tight Junctions

    KAUST Repository

    Tanaka, Hiroo

    2016-01-05

    Claudin protein family members, of which there are at least 27 in humans and mice, polymerize to form tight junctions (TJs) between epithelial cells, in a tissue- and developmental stage-specific manner. Claudins have a paracellular barrier function. In addition, certain claudins function as paracellular channels for small ions and/or solutes by forming selective pores at the TJs, although the specific claudins involved and their functional mechanisms are still in question. Here we show for the first time that claudin-21, which is more highly expressed in the embryonic than the postnatal stages, acts as a paracellular channel for small cations, such as Na+, similar to the typical channel-type claudins claudin-2 and -15. Claudin-21 also allows the paracellular passage of larger solutes. Our findings suggest that claudin-21-based TJs allow the passage of small and larger solutes by both paracellular channel-based and some additional mechanisms. © 2016, American Society for Microbiology. All Rights Reserved.

  11. Toward tight gamma-ray burst luminosity relations

    CERN Document Server

    Qi, Shi

    2011-01-01

    The large scatters of luminosity relations of gamma-ray bursts (GRBs) have been one of the most important reasons that prevent the extensive applications of GRBs in cosmology. Many efforts have been made to seek tight luminosity relations. With the latest sample of 116 GRBs, we investigated 6 two-dimensional (2D) correlations and 14 derived three-dimensional (3D) correlations of GRBs to explore the possibility of decreasing the intrinsic scatters of the luminosity relations of GRBs. We found the 3D correlation of $E_{\\mathrm{peak}}$--$\\tau_{\\mathrm{RT}}$--$L$ to be significantly tighter (at $2 \\sigma$ confidence level) than its corresponding 2D correlations, i.e., the $E_{\\mathrm{peak}}$--$L$ and $\\tau_{\\mathrm{RT}}$--$L$ correlation. In addition, the coefficients before the logarithms of $E_{\\mathrm{peak}}$ and $\\tau_{\\mathrm{RT}}$ in the $E_{\\mathrm{peak}}$--$\\tau_{\\mathrm{RT}}$--$L$ correlation are almost exactly opposite to each other. Inputting this situation as a prior reduces the relation to $L \\propto...

  12. Proteasomes are tightly associated to myofibrils in mature skeletal muscle.

    Science.gov (United States)

    Bassaglia, Yann; Cebrian, José; Covan, Silvia; Garcia, Monica; Foucrier, Jean

    2005-01-15

    Proteasomes are the major actors of nonlysosomal cytoplasmic protein degradation. In particular, these large protein complexes (about 2500 kDa) are considered to be responsible for muscular degradation during skeletal muscle atrophy. Despite their unusual and important size, they are widely described as soluble and mobile in the cytoplasm. In mature skeletal muscle, we have previously observed a sarcomeric distribution of proteasomes, as revealed by the distribution of alpha1/p27K, a subunit of the 20S core-particle (prosome) of proteasome. Here, we extend these observations at the electron microscopic level in vivo. We also show that this sarcomeric pattern is dependent of the extension of the sarcomere. Using isolated myofibrils, we demonstrate that proteasomes are still attached to the myofibrils after the isolation procedure, and reproduce the observations made in vivo. In addition, the extraction of actin by gelsolin largely removes proteasomes from isolated myofibrils, but some of them are held in place after this extraction, showing a sarcomeric disposition in the absence of any detectable actin, and suggesting the existence of another molecular partner for these interactions. From these results, we conclude that most of detectable 20S proteasomes in skeletal muscle cells is tightly attached to the myofibrils. PMID:15561103

  13. Testing underground tanks for leak tightness at LLNL

    International Nuclear Information System (INIS)

    Two types of tank systems are present at the Livermore Site: tanks and associated piping for the storage of fuel (forty-three systems), and tanks or sumps and associated piping for the retention of potentially contaminated wastewater (forty systems). The fuel systems were tested using commercially available test methods: Petro-Tite, Hunter Leak Lokator, Ezy-Chek, and Associated Environmental Systems (A.E.S.). In contrast to fuel tank systems, wastewater systems have containers that are predominantly open at the top and not readily testable. Therefore, a project to test and evaluate all available testing methods was initiated and completed. The commercial method Tank Auditor was determined to be appropriate for testing open-top tanks and sumps and this was the method used to test the majority of the open-top containers. Of the 81 tanks tested, 61 were found to be leak tight, 9 were shown to have leaks, and 11 yielded inconclusive results. Two tanks have not yet been tested because of operational constraints; they are sheduled to be tested within the next two months. Schedules are being developed for the retesting of tanks and for remedial actions

  14. Giant stretchability and reversibility of tightly wound helical carbon nanotubes.

    Science.gov (United States)

    Wu, Jianyang; He, Jianying; Odegard, Gregory M; Nagao, Shijo; Zheng, Quanshui; Zhang, Zhiliang

    2013-09-18

    There is a surging interest in 3D graphitic nanostructures which possess outstanding properties enabling them to be prime candidates for a new generation of nanodevices and energy-absorbing materials. Here we study the stretching instability and reversibility of tightly wound helical carbon nanotubes (HCNTs) by atomistic simulations. The intercoil van der Waals (vdW) interaction-induced flattening of HCNT walls prior to loading is constrained by the defects coordinated for the curvature formation of helices. The HCNTs exhibit extensive stretchability in the range from 400% to 1000% as a result of two distinct deformation mechanisms depending on the HCNT size. For small HCNTs tremendous deformation is achieved by domino-type partial fracture events, whereas for large HCNTs this is accomplished by stepwise buckling of coils. The formation and fracture of edge-closed graphene ribbons occur at lower temperatures, while at elevated temperatures the highly distributed fracture realizes a phenomenal stretchability. The results of cyclic stretching-reversing simulations of large HCNTs display pronounced hysteresis loops, which produce large energy dissipation via full recovery of buckling and vdW bondings. This study provides physical insights into the origins of high ductility and superior reversibility of hybrid CNT structures. PMID:24016308

  15. Business and IT alignment in context

    NARCIS (Netherlands)

    Silvius, A.J.G.

    2013-01-01

    Already for more than two decades, the necessity and desirability of aligning business needs and information technology (IT) capabilities is considered to be one of the key issues in IT management. However, several studies report quite low scores on business and IT alignment (BIA). The question “Why

  16. Sambamba: fast processing of NGS alignment formats

    NARCIS (Netherlands)

    Tarasov, A.; Vilella, A.J.; Cuppen, E.; Nijman, I.J.; Prins, J.C.P.

    2015-01-01

    Sambamba is a high-performance robust tool and library for working with SAM, BAM and CRAM sequence alignment files; the most common file formats for aligned next generation sequencing data. Sambamba is a faster alternative to samtools that exploits multi-core processing and dramatically reduces proc

  17. Automatic alignment of hieroglyphs and transliteration

    OpenAIRE

    Nederhof, Mark Jan

    2009-01-01

    Automatic alignment has important applications in philology, facilitating study of texts on the basis of electronic resources produced by different scholars. A simple technique is presented to realise such alignment for Ancient Egyptian hieroglyphic texts and transliteration. Preliminary experiments with the technique are reported, and plans for future work are discussed. Postprint

  18. A cross-species alignment tool (CAT)

    DEFF Research Database (Denmark)

    Li, Heng; Guan, Liang; Liu, Tao;

    2007-01-01

    BACKGROUND: The main two sorts of automatic gene annotation frameworks are ab initio and alignment-based, the latter splitting into two sub-groups. The first group is used for intra-species alignments, among which are successful ones with high specificity and speed. The other group contains more...

  19. Aligning the μs-ALEX Setup.

    Science.gov (United States)

    Kapanidis, Achillefs; Majumdar, Devdoot; Heilemann, Mike; Nir, Eyal; Weiss, Shimon

    2015-11-01

    To achieve single-molecule sensitivity and thus have the ability to detect single diffusing fluorophores, careful alignment of the microsecond-alternating laser excitation (μs-Alex) setup is crucial. The following protocol describes routine alignment for 2c-ALEX (532 nm/635 nm) with spectral windows G(550-620)R(650-750). PMID:26527766

  20. Compositions for directed alignment of conjugated polymers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinsang; Kim, Bong-Gi; Jeong, Eun Jeong

    2016-04-19

    Conjugated polymers (CPs) achieve directed alignment along an applied flow field and a dichroic ratio of as high as 16.67 in emission from well-aligned thin films and fully realized anisotropic optoelectronic properties of CPs in field-effect transistor (FET).

  1. Evaluating Alignment between Curriculum, Assessment, and Instruction

    Science.gov (United States)

    Martone, Andrea; Sireci, Stephen G.

    2009-01-01

    The authors (a) discuss the importance of alignment for facilitating proper assessment and instruction, (b) describe the three most common methods for evaluating the alignment between state content standards and assessments, (c) discuss the relative strengths and limitations of these methods, and (d) discuss examples of applications of each…

  2. Instructional Alignment under No Child Left Behind

    Science.gov (United States)

    Polikoff, Morgan S.

    2012-01-01

    The alignment of instruction with the content of standards and assessments is the key mediating variable separating the policy of standards-based reform (SBR) from the outcome of improved student achievement. Few studies have investigated SBR's effects on instructional alignment, and most have serious methodological limitations. This research uses…

  3. Optical packet switching without packet alignment

    DEFF Research Database (Denmark)

    Hansen, Peter Bukhave; Danielsen, Søren Lykke; Stubkjær, Kristian

    1998-01-01

    Operation without packet alignment of an all-optical packet switch is proposed and predicted feasible through a detailed traffic analysis. Packet alignment units are eliminated resulting in a simple switch architecture while optimal traffic performance is maintained through the flexibility provided...

  4. Alignment Nashville. Complementary Learning in Action

    Science.gov (United States)

    Bouffard, Suzanne; Malone, Helen

    2007-01-01

    This profile illustrates how Alignment Nashville brings together diverse community members and organizations to leverage existing resources in support of Nashville's youth and the Metro Nashville Public Schools. In addition to a diversified funding structure, Alignment leaders point to three factors that have helped them get the effort off the…

  5. Sambamba : Fast processing of NGS alignment formats

    NARCIS (Netherlands)

    Tarasov, Artem; Vilella, Albert J.; Cuppen, Edwin; Nijman, Isaac J.; Prins, Pjotr

    2015-01-01

    Summary: Sambamba is a high-performance robust tool and library for working with SAM, BAM and CRAM sequence alignment files; the most common file formats for aligned next generation sequencing data. Sambamba is a faster alternative to samtools that exploits multi-core processing and dramatically red

  6. On comparing two structured RNA multiple alignments.

    Science.gov (United States)

    Patel, Vandanaben; Wang, Jason T L; Setia, Shefali; Verma, Anurag; Warden, Charles D; Zhang, Kaizhong

    2010-12-01

    We present a method, called BlockMatch, for aligning two blocks, where a block is an RNA multiple sequence alignment with the consensus secondary structure of the alignment in Stockholm format. The method employs a quadratic-time dynamic programming algorithm for aligning columns and column pairs of the multiple alignments in the blocks. Unlike many other tools that can perform pairwise alignment of either single sequences or structures only, BlockMatch takes into account the characteristics of all the sequences in the blocks along with their consensus structures during the alignment process, thus being able to achieve a high-quality alignment result. We apply BlockMatch to phylogeny reconstruction on a set of 5S rRNA sequences taken from fifteen bacteria species. Experimental results showed that the phylogenetic tree generated by our method is more accurate than the tree constructed based on the widely used ClustalW tool. The BlockMatch algorithm is implemented into a web server, accessible at http://bioinformatics.njit.edu/blockmatch. A jar file of the program is also available for download from the web server. PMID:21121021

  7. The GEM Detector projective alignment simulation system

    International Nuclear Information System (INIS)

    Precision position knowledge (< 25 microns RMS) of the GEM Detector muon system at the Superconducting Super Collider Laboratory (SSCL) is an important physics requirement necessary to minimize sagitta error in detecting and tracking high energy muons that are deflected by the magnetic field within the GEM Detector. To validate the concept of the sagitta correction function determined by projective alignment of the muon detectors (Cathode Strip Chambers or CSCs), the basis of the proposed GEM alignment scheme, a facility, called the ''Alignment Test Stand'' (ATS), is being constructed. This system simulates the environment that the CSCs and chamber alignment systems are expected to experience in the GEM Detector, albeit without the 0.8 T magnetic field and radiation environment. The ATS experimental program will allow systematic study and characterization of the projective alignment approach, as well as general mechanical engineering of muon chamber mounting concepts, positioning systems and study of the mechanical behavior of the proposed 6 layer CSCs. The ATS will consist of a stable local coordinate system in which mock-ups of muon chambers (i.e., non-working mechanical analogs, representing the three superlayers of a selected barrel and endcap alignment tower) are implemented, together with a sufficient number of alignment monitors to overdetermine the sagitta correction function, providing a self-consistency check. This paper describes the approach to be used for the alignment of the GEM muon system, the design of the ATS, and the experiments to be conducted using the ATS

  8. Achieving Organisational Change through Values Alignment

    Science.gov (United States)

    Branson, Christopher M.

    2008-01-01

    Purpose: The purpose of this paper is to, first, establish the interdependency between the successful achievement of organisational change and the attainment of values alignment within an organisation's culture and then, second, to describe an effective means for attaining such values alignment. Design/methodology/approach: Literature from the…

  9. SOA-Driven Business-Software Alignment

    NARCIS (Netherlands)

    Shishkov, Boris; Sinderen, van Marten; Quartel, Dick

    2006-01-01

    The alignment of business processes and their supporting application software is a major concern during the initial software design phases. This paper proposes a design approach addressing this problem of business-software alignment. The approach takes an initial business model as a basis in derivin

  10. Vacuum alignment with(out) elementary scalars

    CERN Document Server

    Alanne, Tommi; Meroni, Aurora; Sannino, Francesco

    2016-01-01

    We systematically elucidate differences and similarities of the vacuum alignment issue in composite and renormalizable elementary extensions of the Standard Model featuring a pseudo-Goldstone Higgs. We also provide general conditions for the stability of the vacuum in the elementary framework, thereby extending previous studies of the vacuum alignment.

  11. STELLAR: fast and exact local alignments

    Directory of Open Access Journals (Sweden)

    Weese David

    2011-10-01

    Full Text Available Abstract Background Large-scale comparison of genomic sequences requires reliable tools for the search of local alignments. Practical local aligners are in general fast, but heuristic, and hence sometimes miss significant matches. Results We present here the local pairwise aligner STELLAR that has full sensitivity for ε-alignments, i.e. guarantees to report all local alignments of a given minimal length and maximal error rate. The aligner is composed of two steps, filtering and verification. We apply the SWIFT algorithm for lossless filtering, and have developed a new verification strategy that we prove to be exact. Our results on simulated and real genomic data confirm and quantify the conjecture that heuristic tools like BLAST or BLAT miss a large percentage of significant local alignments. Conclusions STELLAR is very practical and fast on very long sequences which makes it a suitable new tool for finding local alignments between genomic sequences under the edit distance model. Binaries are freely available for Linux, Windows, and Mac OS X at http://www.seqan.de/projects/stellar. The source code is freely distributed with the SeqAn C++ library version 1.3 and later at http://www.seqan.de.

  12. Improving the alignment quality of consistency based aligners with an evaluation function using synonymous protein words.

    Directory of Open Access Journals (Sweden)

    Hsin-Nan Lin

    Full Text Available Most sequence alignment tools can successfully align protein sequences with higher levels of sequence identity. The accuracy of corresponding structure alignment, however, decreases rapidly when considering distantly related sequences (<20% identity. In this range of identity, alignments optimized so as to maximize sequence similarity are often inaccurate from a structural point of view. Over the last two decades, most multiple protein aligners have been optimized for their capacity to reproduce structure-based alignments while using sequence information. Methods currently available differ essentially in the similarity measurement between aligned residues using substitution matrices, Fourier transform, sophisticated profile-profile functions, or consistency-based approaches, more recently.In this paper, we present a flexible similarity measure for residue pairs to improve the quality of protein sequence alignment. Our approach, called SymAlign, relies on the identification of conserved words found across a sizeable fraction of the considered dataset, and supported by evolutionary analysis. These words are then used to define a position specific substitution matrix that better reflects the biological significance of local similarity. The experiment results show that the SymAlign scoring scheme can be incorporated within T-Coffee to improve sequence alignment accuracy. We also demonstrate that SymAlign is less sensitive to the presence of structurally non-similar proteins. In the analysis of the relationship between sequence identity and structure similarity, SymAlign can better differentiate structurally similar proteins from non- similar proteins. We show that protein sequence alignments can be significantly improved using a similarity estimation based on weighted n-grams. In our analysis of the alignments thus produced, sequence conservation becomes a better indicator of structural similarity. SymAlign also provides alignment visualization that

  13. The Synthesis of Highly Aligned Cupric Oxide Nanowires by Heating Copper Foil

    Directory of Open Access Journals (Sweden)

    Jianbo Liang

    2011-01-01

    Full Text Available We have investigated the effects of grain size and orientation of copper substrates for the growth of cupric oxide nanowires by thermal oxidation method. Long, less-roughness, high-density, and aligned cupric oxide nanowires have been synthesized by heating (200 oriented copper foils with small grain size in air gas. Long and aligned nanowires of diameter around 80 nm can only be formed within a short temperature range from 400 to 700°C. On the other hand, uniform, smooth-surface, and aligned nanowires were not formed in the case of larger crystallite size of copper foils with (111 and (200 orientation. Smaller grain size of copper foil with (200 orientation is favorable for the growth of highly aligned, smooth surface, and larger-diameter nanowires by thermal oxidation method.

  14. The Shape-Alignment relation in $\\Lambda$CDM Cosmic Structures

    CERN Document Server

    Basilakos, S; Yepes, G; Gottl"ober, S; Turchaninov, V I

    2006-01-01

    In this paper we study the supercluster - cluster morphological properties using one of the largest ($2\\times 512^{3}$) SPH+N-body simulations of large scale structure formation in a $\\Lambda$CDM model, based on the publicly available code GADGET. We find that filamentary (prolate-like) shapes are the dominant supercluster and cluster dark matter halo morphological feature, in agreement with previous studies. However, the baryonic gas component of the clusters is predominantly spherical.We investigate the alignment between cluster halos (using either their DM or baryonic components) and their parent supercluster major-axis orientation, finding that clusters show such a preferential alignment.Combining the shape and the alignment statistics, we also find that the amplitude of supercluster - cluster alignment increases although weakly with supercluster filamentariness.

  15. Dynamic interferometer alignment and its utility in UV Fourier transform spectrometer systems

    Science.gov (United States)

    Dorval, Rick K.; Engel, James R.; Wyntjes, Geert J.

    1993-01-01

    Dynamic alignment has been demonstrated as a practical approach to alignment maintenance for systems in the infrared region of the spectrum. On the basis of work done by OPTRA, this technique was introduced in commercial Fourier transform spectrometer systems in 1982 and in various forms is now available from a number of manufacturers. This paper reports on work by OPTRA to extend the basic technique to systems operating in the ultraviolet. In addition, this paper reports the preliminary results of the development of an alignment system using a laser diode in place of a gas laser normally found in dynamic alignment systems. A unique optical system and spatial heterodyne technique allows for achievement of a metrology system with characteristics that fully satisfy the requirements of an ultraviolet spectrometer system.

  16. Glucose Information for Tight Glycemic Control: Different Methods with Different Challenges

    OpenAIRE

    Weber, Christian; Neeser, Kurt

    2010-01-01

    Rigorous glucose control is essential for prevention of diabetes-related complications in diabetes patients. Even without diabetes, tight glucose control is beneficial in hospitalized, critically ill patients.

  17. Accelerated large-scale multiple sequence alignment

    Directory of Open Access Journals (Sweden)

    Lloyd Scott

    2011-12-01

    Full Text Available Abstract Background Multiple sequence alignment (MSA is a fundamental analysis method used in bioinformatics and many comparative genomic applications. Prior MSA acceleration attempts with reconfigurable computing have only addressed the first stage of progressive alignment and consequently exhibit performance limitations according to Amdahl's Law. This work is the first known to accelerate the third stage of progressive alignment on reconfigurable hardware. Results We reduce subgroups of aligned sequences into discrete profiles before they are pairwise aligned on the accelerator. Using an FPGA accelerator, an overall speedup of up to 150 has been demonstrated on a large data set when compared to a 2.4 GHz Core2 processor. Conclusions Our parallel algorithm and architecture accelerates large-scale MSA with reconfigurable computing and allows researchers to solve the larger problems that confront biologists today. Program source is available from http://dna.cs.byu.edu/msa/.

  18. Bokeh Mirror Alignment for Cherenkov Telescopes

    CERN Document Server

    Ahnen, M L; Balbo, M; Bergmann, M; Biland, A; Blank, M; Bretz, T; Bruegge, K A; Buss, J; Domke, M; Dorner, D; Einecke, S; Hempfling, C; Hildebrand, D; Hughes, G; Lustermann, W; Mannheim, K; Mueller, S A; Neise, D; Neronov, A; Noethe, M; Overkemping, A -K; Paravac, A; Pauss, F; Rhode, W; Shukla, A; Temme, F; Thaele, J; Toscano, S; Vogler, P; Walter, R; Wilbert, A

    2016-01-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures and high image intensities to map the faint Cherenkov light emitted from cosmic ray air showers onto their image sensors. Segmented reflectors fulfill these needs, and composed from mass production mirror facets they are inexpensive and lightweight. However, as the overall image is a superposition of the individual facet images, alignment remains a challenge. Here we present a simple, yet extendable method, to align a segmented reflector using its Bokeh. Bokeh alignment does not need a star or good weather nights but can be done even during daytime. Bokeh alignment optimizes the facet orientations by comparing the segmented reflectors Bokeh to a predefined template. The optimal Bokeh template is highly constricted by the reflector's aperture and is easy accessible. The Bokeh is observed using the out of focus image of a near by point like light source in a distance of about 10 focal lengths. We introduce Bokeh alignment ...

  19. Operational performance of the Antares alignment system

    International Nuclear Information System (INIS)

    A review of the operational performance of the alignment system for the large Antares optical system is presented. The alignment of twenty-four optical channels consisting of two hundred optical elements is verified and established as required prior to each target shot for this CO2 laser fusion test facility. The overall system design included features such as automatic operation, data base driven controls, self calibration, provisions for initial optical alignment set up, and system aided fault location. The system approach employed two alignment stations which sequentially viewed the 24 optical channels (sectors) and could be used for prealignments and calibrations. Closed-loop operations via the computer permit rapid mirror alignments. The performance of the applied techniques and devices is evaluated and compared to the required performance specifically from the standpoint of accuracy and shot rate. Overall system performance with verification by actual target shots is presented

  20. Semiautomatic beam-based LHC collimator alignment

    CERN Document Server

    Valentino, Gianluca; Bruce, Roderik; Wollmann, Daniel; Sammut, Nicholas; Rossi, Adriana; Redaelli, Stefano

    2012-01-01

    Full beam-based alignment of the LHC collimation system was a time-consuming procedure (up to 28 hours) as the collimators were set up manually. A yearly alignment campaign has been sufficient for now, although in the future due to tighter tolerances this may lead to a decrease in the cleaning efficiency if machine parameters such as the beam orbit drift over time. Automating the collimator setup procedure can reduce the beam time for collimator setup and allow for more frequent alignments, therefore reducing the risk of performance degradation. This article describes the design and testing of a semiautomatic algorithm as a first step towards a fully automatic setup procedure. The parameters used to measure the accuracy and performance of the alignment are defined and determined from experimental data. A comparison of these measured parameters at 450 GeV and 3.5 TeV with manual and semiautomatic alignment is provided.

  1. Array tomography: semiautomated image alignment.

    Science.gov (United States)

    Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J

    2010-11-01

    Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time-consuming and require some practice to perfect. Successful array tomography requires that the captured images be properly stacked and aligned, and the software to achieve these ends is freely available. This protocol describes the construction of volumetric image stacks from images of fluorescently labeled arrays for three-dimensional image visualization, analysis, and archiving. PMID:21041400

  2. R3D Align: global pairwise alignment of RNA 3D structures using local superpositions

    Science.gov (United States)

    Rahrig, Ryan R.; Leontis, Neocles B.; Zirbel, Craig L.

    2010-01-01

    Motivation: Comparing 3D structures of homologous RNA molecules yields information about sequence and structural variability. To compare large RNA 3D structures, accurate automatic comparison tools are needed. In this article, we introduce a new algorithm and web server to align large homologous RNA structures nucleotide by nucleotide using local superpositions that accommodate the flexibility of RNA molecules. Local alignments are merged to form a global alignment by employing a maximum clique algorithm on a specially defined graph that we call the ‘local alignment’ graph. Results: The algorithm is implemented in a program suite and web server called ‘R3D Align’. The R3D Align alignment of homologous 3D structures of 5S, 16S and 23S rRNA was compared to a high-quality hand alignment. A full comparison of the 16S alignment with the other state-of-the-art methods is also provided. The R3D Align program suite includes new diagnostic tools for the structural evaluation of RNA alignments. The R3D Align alignments were compared to those produced by other programs and were found to be the most accurate, in comparison with a high quality hand-crafted alignment and in conjunction with a series of other diagnostics presented. The number of aligned base pairs as well as measures of geometric similarity are used to evaluate the accuracy of the alignments. Availability: R3D Align is freely available through a web server http://rna.bgsu.edu/R3DAlign. The MATLAB source code of the program suite is also freely available for download at that location. Supplementary information: Supplementary data are available at Bioinformatics online. Contact: r-rahrig@onu.edu PMID:20929913

  3. Tracing magnetic fields with aligned grains

    Energy Technology Data Exchange (ETDEWEB)

    Lazarian, A. [Astronomy Department, University of Wisconsin-Madison, 475 N. Charter St., Madison, WI 53706 (United States)]. E-mail: lazarian@astro.wisc.edu

    2007-07-15

    Magnetic fields play a crucial role in various astrophysical processes, including star formation, accretion of matter, transport processes (e.g., transport of heat), and cosmic rays. One of the easiest ways to determine the magnetic field direction is via polarization of radiation resulting from extinction or/and emission by aligned dust grains. Reliability of interpretation of the polarization maps in terms of magnetic fields depends on how well we understand the grain-alignment theory. Explaining what makes grains aligned has been one of the big issues of the modern astronomy. Numerous exciting physical effects have been discovered in the course of research undertaken in this field. As both the theory and observations matured, it became clear that the grain-alignment phenomenon is inherent not only in diffuse interstellar medium or molecular clouds but also is a generic property of the dust in circumstellar regions, interplanetary space and cometary comae. Currently the grain-alignment theory is a predictive one, and its results nicely match observations. Among its predictions is a subtle phenomenon of radiative torques. This phenomenon, after having stayed in oblivion for many years after its discovery, is currently viewed as the most powerful means of alignment. In this article, I shall review the basic physical processes involved in grain alignment, and the currently known mechanisms of alignment. I shall also discuss possible niches for different alignment mechanisms. I shall dwell on the importance of the concept of grain helicity for understanding of many properties of grain alignment, and shall demonstrate that rather arbitrarily shaped grains exhibit helicity when they interact with gaseous and radiative flows.

  4. Tight-Binding Molecular Dynamics Simulations of Shock-Compressed Hydrocarbons

    Science.gov (United States)

    Kress, J. D.; Bickham, S. R.; Holian, B. L.; Collins, L. A.

    1999-06-01

    We have used tight-binding molecular dynamics to simulate shock waves in liquid hydocarbons. The equations of motion in supercells containing as many as 1024 methane and 576 benzene molecules (8192 and 17,280 valence electrons, respectively) are integrated using an O(N) electronic structure algorithm(S. Goedecker and L. Columbo, Phys. Rev. Lett. 73), 122 (1994); A.F. Voter, J.D. Kress and R.N. Silver, Phys. Rev. B 53, 12733 (1996) implemented on a massively parallel computer. In the non-equilibrium shock compression simulation, uniaxial contracting periodic boundary conditions were employed, with both ends of an elongated supercell moving inward at a constant (piston) velocity. The velocities of the shock waves created in this manner are compared to gas gun experimentsfootnote W. J. Nellis et al., J. Chem. Phys. 75, 3055 (1981). Analysis of the medium between the piston and shock front indicates that methane is decomposed into molecular hydrogen and carbon residue, while shocked benzene forms a mixture of hydrocarbons and molecular hydrogen. The dynamics of these chemical transformations will be discussed.

  5. The tight relation between X-ray and ultraviolet luminosity of quasars

    CERN Document Server

    Lusso, E

    2016-01-01

    The observed relation between the soft X-ray and the optical-ultraviolet emission in active galactic nuclei (AGN) is non-linear and it is usually parametrized as a dependence between the logarithm of the monochromatic luminosity at 2500 {\\AA} and at 2 keV. Previous investigations have found that the dispersion of this relation is rather high (~0.35-0.4 in log units), which may be caused by measurement uncertainties, variability, and intrinsic dispersion due to differences in the AGN physical properties (e.g. different accretion modes). We show that, once optically-selected quasars with homogeneous SED and X-ray detection are selected, and dust reddened and/or gas obscured objects are not included, the measured dispersion drops to significantly lower values (i.e. ~0.21-0.24 dex). We show that the residual dispersion is due to some extent to variability, and to remaining measurement uncertainties. Therefore, the real physical intrinsic dispersion should be <0.21 dex. Such a tight relation, valid over 4 decad...

  6. Toward Tight Gamma-Ray Burst Luminosity Relations

    Science.gov (United States)

    Qi, Shi; Lu, Tan

    2012-04-01

    The large scatters of luminosity relations of gamma-ray bursts (GRBs) have been one of the most important reasons preventing the extensive application of GRBs in cosmology. Many efforts have been made to seek tight luminosity relations. With the latest sample of 116 GRBs with measured redshift and spectral parameters, we investigate 6 two-dimensional (2D) correlations and 14 derived three-dimensional (3D) correlations of GRBs to explore the possibility of decreasing the intrinsic scatters of the luminosity relations of GRBs. We find the 3D correlation of E peak-τRT-L to be evidently tighter (at the 2σ confidence level) than its corresponding 2D correlations, i.e., the E peak-L and τRT-L correlations. In addition, the coefficients before the logarithms of E peak and τRT in the E peak-τRT-L correlation are almost exact opposites of each other. Inputting this situation as a prior reduces the relation to Lvprop(E'peak/τRT')0.842 ± 0.064, where E'peak and τ'RT denote the peak energy and minimum rise time in the GRB rest frame. We discuss how our findings can be interpreted/understood in the framework of the definition of the luminosity (energy released in units of time). Our argument about the connection between the luminosity relations of GRBs and the definition of the luminosity provides a clear direction for exploring tighter luminosity relations of GRBs in the future.

  7. Conservative tightly-coupled simulations of stochastic multiscale systems

    Science.gov (United States)

    Taverniers, Søren; Pigarov, Alexander Y.; Tartakovsky, Daniel M.

    2016-05-01

    Multiphysics problems often involve components whose macroscopic dynamics is driven by microscopic random fluctuations. The fidelity of simulations of such systems depends on their ability to propagate these random fluctuations throughout a computational domain, including subdomains represented by deterministic solvers. When the constituent processes take place in nonoverlapping subdomains, system behavior can be modeled via a domain-decomposition approach that couples separate components at the interfaces between these subdomains. Its coupling algorithm has to maintain a stable and efficient numerical time integration even at high noise strength. We propose a conservative domain-decomposition algorithm in which tight coupling is achieved by employing either Picard's or Newton's iterative method. Coupled diffusion equations, one of which has a Gaussian white-noise source term, provide a computational testbed for analysis of these two coupling strategies. Fully-converged ("implicit") coupling with Newton's method typically outperforms its Picard counterpart, especially at high noise levels. This is because the number of Newton iterations scales linearly with the amplitude of the Gaussian noise, while the number of Picard iterations can scale superlinearly. At large time intervals between two subsequent inter-solver communications, the solution error for single-iteration ("explicit") Picard's coupling can be several orders of magnitude higher than that for implicit coupling. Increasing the explicit coupling's communication frequency reduces this difference, but the resulting increase in computational cost can make it less efficient than implicit coupling at similar levels of solution error, depending on the communication frequency of the latter and the noise strength. This trend carries over into higher dimensions, although at high noise strength explicit coupling may be the only computationally viable option.

  8. Pores in the epidermis: aquaporins and tight junctions.

    Science.gov (United States)

    Brandner, J M

    2007-12-01

    Water homeostasis of the epidermis is important for the appearance and physical properties of the skin, as well as for water balance in the body. It depends on several factors, e.g. barrier quality, uptake of water into the epidermis, concentration of water-retaining humectants, and external humidity. Aquaporins (AQPs) are pores in the plasmamembranes of cells. Monomeric AQPs form barrel-like structures that are primarily water selective, some AQPs also transport glycerol and possibly other small solutes. In the epidermis, AQP3 is the predominant AQP. It is localized mainly in basal but also in suprabasal layers of the epidermis and is permeable for water as well as for glycerol, a humectant. Mice deficient in AQP3 exhibit reduced stratum corneum (SC) hydration and impaired SC barrier recovery after SC removal. In skin diseases associated with elevated transepidermal water loss (TEWL) and reduced SC hydration, altered expression of AQP3 was shown. Tight junctions (TJ) are cell-cell junctions, which play a central role in sealing the intercellular space of cell sheets and thereby establishing a paracellular barrier. Within the TJ, pores are postulated to exist, which allow the controlled diffusion of water and solutes via the paracellular pathway. In the epidermis, TJ structures were demonstrated in the stratum granulosum whereas TJ proteins were found in all viable layers. Mice which overexpress or are deficient of key-proteins of TJ die soon after birth because of a tremendous TEWL. In various skin diseases that are accompanied by elevated TEWL and reduced skin hydration, staining patterns of TJ proteins are altered. This review will summarize our current knowledge of the involvement of AQPs and TJ in the water homeostasis of the epidermis. PMID:18489380

  9. Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules

    International Nuclear Information System (INIS)

    We have succeeded in realizing an inclined homeotropic alignment of liquid crystal (LC) molecules by using photo-aligned films of a polyimide containing azobenzene in the backbone structure. To induce such an LC alignment, a side chain structure was introduced into the backbone structure. The LC pretilt angle, measured from the surface normal, could be controlled up to 1.75o by varying the light exposure in oblique angle irradiation with unpolarized light. Its thermal stability was examined by annealing the LC cell at 100 deg. C. No change was observed in the pretilt angle even after annealing for 36 h, indicative of its excellent thermal stability. Since photo-alignment has patterning capability, the photo-aligned polyimide film is expected as a promising alignment film for multi-domain vertical alignment mode LC displays

  10. Face Alignment via Regressing Local Binary Features.

    Science.gov (United States)

    Ren, Shaoqing; Cao, Xudong; Wei, Yichen; Sun, Jian

    2016-03-01

    This paper presents a highly efficient and accurate regression approach for face alignment. Our approach has two novel components: 1) a set of local binary features and 2) a locality principle for learning those features. The locality principle guides us to learn a set of highly discriminative local binary features for each facial landmark independently. The obtained local binary features are used to jointly learn a linear regression for the final output. This approach achieves the state-of-the-art results when tested on the most challenging benchmarks to date. Furthermore, because extracting and regressing local binary features are computationally very cheap, our system is much faster than previous methods. It achieves over 3000 frames per second (FPS) on a desktop or 300 FPS on a mobile phone for locating a few dozens of landmarks. We also study a key issue that is important but has received little attention in the previous research, which is the face detector used to initialize alignment. We investigate several face detectors and perform quantitative evaluation on how they affect alignment accuracy. We find that an alignment friendly detector can further greatly boost the accuracy of our alignment method, reducing the error up to 16% relatively. To facilitate practical usage of face detection/alignment methods, we also propose a convenient metric to measure how good a detector is for alignment initialization.

  11. Galaxy alignment on large and small scales

    CERN Document Server

    Kang, X; Wang, Y O; Dutton, A; Macciò, A

    2014-01-01

    Galaxies are not randomly distributed across the universe but showing different kinds of alignment on different scales. On small scales satellite galaxies have a tendency to distribute along the major axis of the central galaxy, with dependence on galaxy properties that both red satellites and centrals have stronger alignment than their blue counterparts. On large scales, it is found that the major axes of Luminous Red Galaxies (LRGs) have correlation up to 30Mpc/h. Using hydro-dynamical simulation with star formation, we investigate the origin of galaxy alignment on different scales. It is found that most red satellite galaxies stay in the inner region of dark matter halo inside which the shape of central galaxy is well aligned with the dark matter distribution. Red centrals have stronger alignment than blue ones as they live in massive haloes and the central galaxy-halo alignment increases with halo mass. On large scales, the alignment of LRGs is also from the galaxy-halo shape correlation, but with some ex...

  12. Panorama 2011: Unconventional gas and water

    International Nuclear Information System (INIS)

    For a number of years now, the rapid development of unconventional gas use in North America has been revolutionising the natural gas market. This generic term refers to several production types, such as tight gas, shale gas and coal bed methane. What they have in common is that the rock needs to be 'stimulated' in order to extract gas from it that can be commercially produced. These methods (horizontal drilling, hydraulic fracturing) all involve sensible management of the water needed for gas production. (author)

  13. Ranking horizontal-well sites in tight, naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Zammerilli, A.M. (US DOE Morgantown Energy Technology Center, Morgantown, WV (US))

    1991-01-01

    This paper describes a method to examine the relative merits of locations for horizontal wells in a naturally fractured shale gas basin. The methodology examines noncontrollable variables (existing reservoir pressure, pay-zone thickness, and success ratios) as well as controllable variables (gas price and drilling costs) to arrive at the profitability for a horizontal well project in a candidate area. An analysis of the expected monetary value (EMV) and a cash flow model are used to obtain a distribution of cash flow levels that yields a determination of whether a project is likely to succeed. Ranges of profitability for an unstimulated horizontal well are presented graphically. With this approach, the most likely areas for horizontal drilling to be economically and technically successful are identified easily and quickly.

  14. The tiling C*-algebra viewed as a tight inverse semigroup algebra

    OpenAIRE

    Exel, Ruy; Gonçalves, Daniel; Starling, Charles

    2011-01-01

    We realize Kellendonk'?s C*-algebra of an aperiodic tiling as the tight C*-algebra of the inverse semigroup associated to the tiling, thus providing further evidence that the tight C*-algebra is a good candidate to be the natural associative algebra to go along with an inverse semigroup.

  15. An efficient magnetic tight-binding method for transition metals and alloys

    DEFF Research Database (Denmark)

    Barreteau, Cyrille; Spanjaard, Daniel; Desjonquères, Marie-Catherine

    2016-01-01

    An efficient parameterized self-consistent tight-binding model for transition metals using s, p and d valence atomic orbitals as a basis set is presented. The parameters of our tight-binding model for pure elements are determined from a fit to bulk ab-initio calculations. A very simple procedure ...

  16. Phase coherence in tight-binding models with nonrandom long-range hopping

    NARCIS (Netherlands)

    Balagurov, DB; Malyshev, VA; Adame, FD

    2004-01-01

    The density of states, even for a perfectly ordered tight-binding model, can exhibit a tail-like feature at the top of the band, provided the hopping integral falls off in space slowly enough. We apply the coherent potential approximation to study the eigenstates of a tight-binding Hamiltonian with

  17. Tightness of M-estimators for multiple linear regression in time series

    DEFF Research Database (Denmark)

    Johansen, Søren; Nielsen, Bent

    We show tightness of a general M-estimator for multiple linear regression in time series. The positive criterion function for the M-estimator is assumed lower semi-continuous and sufficiently large for large argument: Particular cases are the Huber-skip and quantile regression. Tightness requires...

  18. Rotational Alignment Altered by Source Position Correlations

    Science.gov (United States)

    Jacobs, Chris S.; Heflin, M. B.; Lanyi, G. E.; Sovers, O. J.; Steppe, J. A.

    2010-01-01

    In the construction of modern Celestial Reference Frames (CRFs) the overall rotational alignment is only weakly constrained by the data. Therefore, common practice has been to apply a 3-dimensional No-Net-Rotation (NNR) constraint in order to align an under-construction frame to the ICRF. We present evidence that correlations amongst source position parameters must be accounted for in order to properly align a CRF at the 5-10 (mu)as level of uncertainty found in current work. Failure to do so creates errors at the 10-40 (mu)as level.

  19. What drives natural gas prices?

    OpenAIRE

    Stephen P. A. Brown; Yücel, Mine K.

    2007-01-01

    For many years, fuel switching between natural gas and residual fuel oil kept natural gas prices closely aligned with those for crude oil. More recently, however, the number of U.S. facilities able to switch between natural gas and residual fuel oil has declined, and over the past five years, U.S. natural gas prices have been on an upward trend with crude oil prices but with considerable independent movement. Natural gas market analysts generally emphasize weather and inventories as drivers o...

  20. Aligned Fibrous Scaffold Induced Aligned Growth of Corneal Stroma Cells in vitro Culture

    Institute of Scientific and Technical Information of China (English)

    GAO Yan; YAN Jing; CUI Xue-jun; WANG Hong-yan; WANG Qing

    2012-01-01

    To investigate the contribution of fibre arrangement to guiding the aligned growth of corneal stroma cells,aligned and randomly oriented fibrous scaffolds of gelatin and poly-L-lactic acid(PLLA) were fabricated by electrospinning.A comparative study of two different systems with corneal stroma cells on randomly organized and aligned fibres were conducted.The efficiency of the scaffolds for inducing the aligned growth of cells was assessed by morphological observation and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT) assay.Results show that the cells cultured on both randomly oriented and aligned scaffolds maintained normal morphology and well spreading as well as long term proliferation.Importantly,corneal stroma cells grew high orderly on the aligned scaffold,while the cells grew disordered on the randomly oriented scaffold.Moreover,the cells exhibited higher viability in aligned scaffold than that in randomly oriented scaffold.These results indcate that electrospinng to prepare aligned fibrous scaffolds has provided an effective approach to the aligned growth of corneal stroma cells in vitro.Our findings that fiber arrangement plays a crucial role in guiding the aligned growth of cells may be helpful to the development of better biomaterials for tissue engineered cornea.

  1. Robust and Efficient Parametric Face Alignment

    NARCIS (Netherlands)

    Tzimiropoulos, Georgios; Zafeiriou, Stefanos; Pantic, Maja

    2011-01-01

    We propose a correlation-based approach to parametric object alignment particularly suitable for face analysis applications which require efficiency and robustness against occlusions and illumination changes. Our algorithm registers two images by iteratively maximizing their correlation coefficient

  2. Alignment of the NOMAD-STAR detector

    CERN Document Server

    Cervera-Villanueva, A

    2000-01-01

    This note describes the alignment of the NOMAD-STAR detector. This is the B/sub 4/C-silicon target installed in the NOMAD spectrometer in 1997. NOMAD-STAR is composed of modules of 12 silicon detectors each giving a total length of 72 cm. Ten of these modules (called ladders) are assembled to form a layer. There are five layers interleaved with passive boron carbide plates. The total surface of silicon is 1.14 m /sup 2/. Energetic muons from the flat-top of the CERN SPS cycle provide the necessary information to perform a very precise software alignment. This alignment is needed to ensure that the impact parameter measurement needed for the identification of taus in a detector like NOMAD-STAR will not be limited by the error in the alignment. (15 refs).

  3. Aligner for Elastic Collisions of Dropped Balls.

    Science.gov (United States)

    Mellen, Walter Roy

    1995-01-01

    Discusses an aligner that permits dropping a stack of any number of balls of different sizes, elasticities, hardnesses, or types to observe the rebound of the top ball. Experimental results allow a reasonable comparison with theory. (MVL)

  4. Alignment free characterization of 2D gratings

    CERN Document Server

    Madsen, Morten Hannibal; Hansen, Poul-Erik; Jørgensen, Jan Friis

    2015-01-01

    Fast characterization of 2-dimensional gratings is demonstrated using a Fourier lens optical system and a differential optimization algorithm. It is shown that both the grating specific parameters such as the basis vectors and the angle between them and the alignment of the sample, such as the rotation of the sample around the x-, y-, and z-axis, can be deduced from a single measurement. More specifically, the lattice vectors and the angle between them have been measured, while the corrections of the alignment parameters are used to improve the quality of the measurement, and hence reduce the measurement uncertainty. Alignment free characterization is demonstrated on both a 2D hexagonal grating with a period of 700 nm and a checkerboard grating with a pitch of 3000 nm. The method can also be used for both automatic alignment and in-line characterization of gratings.

  5. Precision alignment of permanent magnet drift tubes

    International Nuclear Information System (INIS)

    The Lawrence Berkeley National Laboratory (LBNL) technique of drift-tube alignment has been resurrected at Los Alamos for the precision alignment of 1-cm-core drift tubes that carry high gradient rare-earth-cobalt quadrupoles. Because the quadrupoles cannot be switched off, this technique is not applicable to a drift-tube assembly, but tests indicate that individual magnetic centers can be detected with a precision of +/-0.003 mm. Methods of transferring this information to machined alignment flats on the sides of the drift-tube body are discussed. With measurements of drift tubes designed for a 100-mA, 425-MHz drift-tube linac, offsets between the geometric and magnetic axes of up to +/-0.05 mm were detected following final assembly and welding. This degree of offset is serious if not accommodated, because it represents the entire alignment tolerance for the 40-cell tank. The measurement equipment and technique are described

  6. Faster exon assembly by sparse spliced alignment

    CERN Document Server

    Tiskin, Alexander

    2007-01-01

    Assembling a gene from candidate exons is an important problem in computational biology. Among the most successful approaches to this problem is \\emph{spliced alignment}, proposed by Gelfand et al., which scores different candidate exon chains within a DNA sequence of length $m$ by comparing them to a known related gene sequence of length n, $m = \\Theta(n)$. Gelfand et al.\\ gave an algorithm for spliced alignment running in time O(n^3). Kent et al.\\ considered sparse spliced alignment, where the number of candidate exons is O(n), and proposed an algorithm for this problem running in time O(n^{2.5}). We improve on this result, by proposing an algorithm for sparse spliced alignment running in time O(n^{2.25}). Our approach is based on a new framework of \\emph{quasi-local string comparison}.

  7. Robust and resistant 2D shape alignment

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Eiriksson, Hrafnkell

    2001-01-01

    We express the alignment of 2D shapes as the minimization of the norm of a linear vector function. The minimization is done in the \\$l\\_1\\$, \\$l\\_2\\$ and the \\$l\\_\\$\\backslash\\$infty\\$ norms using well known standard numerical methods. In particular, the \\$l\\_1\\$ and the \\$l\\_\\$\\backslash\\$infty\\......We express the alignment of 2D shapes as the minimization of the norm of a linear vector function. The minimization is done in the \\$l\\_1\\$, \\$l\\_2\\$ and the \\$l\\_\\$\\backslash\\$infty\\$ norms using well known standard numerical methods. In particular, the \\$l\\_1\\$ and the \\$l......\\_\\$\\backslash\\$infty\\$ norm alignments are formulated as linear programming problems. The linear vector function formulation along with the different norms results in alignment methods that are both resistant from influence from outliers, robust wrt. errors in the annotation and capable of handling missing datapoints...

  8. EURRECA—Framework for Aligning Micronutrient Recommendations

    NARCIS (Netherlands)

    Veer, van 't P.; Grammatikaki, E.; Matthys, C.; Raats, M.M.; Contor, L.

    2013-01-01

    There is currently no standard approach for deriving micronutrient recommendations, and large variations exist across Europe, causing confusion among consumers, food producers, and policy makers. More aligned information could influence dietary behaviors and potentially lead to a healthier populatio

  9. Theoretical Analysis of the Mechanism of Fracture Network Propagation with Stimulated Reservoir Volume (SRV Fracturing in Tight Oil Reservoirs.

    Directory of Open Access Journals (Sweden)

    Yuliang Su

    Full Text Available Stimulated reservoir volume (SRV fracturing in tight oil reservoirs often induces complex fracture-network growth, which has a fundamentally different formation mechanism from traditional planar bi-winged fracturing. To reveal the mechanism of fracture network propagation, this paper employs a modified displacement discontinuity method (DDM, mechanical mechanism analysis and initiation and propagation criteria for the theoretical model of fracture network propagation and its derivation. A reasonable solution of the theoretical model for a tight oil reservoir is obtained and verified by a numerical discrete method. Through theoretical calculation and computer programming, the variation rules of formation stress fields, hydraulic fracture propagation patterns (FPP and branch fracture propagation angles and pressures are analyzed. The results show that during the process of fracture propagation, the initial orientation of the principal stress deflects, and the stress fields at the fracture tips change dramatically in the region surrounding the fracture. Whether the ideal fracture network can be produced depends on the geological conditions and on the engineering treatments. This study has both theoretical significance and practical application value by contributing to a better understanding of fracture network propagation mechanisms in unconventional oil/gas reservoirs and to the improvement of the science and design efficiency of reservoir fracturing.

  10. Proceedings of the natural gas research and development contractors review meeting

    Energy Technology Data Exchange (ETDEWEB)

    Malone, R.D.; Shoemaker, H.D.; Byrer, C.W. (eds.)

    1990-11-01

    The purpose of this meeting was to present results of the research in the DOE-sponsored Natural Gas Program, and simultaneously to provide a forum for real-time technology transfer, to the active research community, to the interested public, and to the natural gas industry, who are the primary users of this technology. The current research focus is to expand the base of near-term and mid-term economic gas resources through research activities in Eastern Tight Gas, Western Tight Gas, Secondary Gas Recovery (increased recovery of gas from mature fields); to enhance utilization, particularly of remote gas resources through research in Natural Gas to Liquids Conversion; and to develop additional, long term, potential gas resources through research in Gas Hydrates and Deep Gas. With the increased national emphasis on the use of natural gas, this forum has been expanded to include summaries of DOE-sponsored research in energy-related programs and perspectives on the importance of gas to future world energy. Thirty-two papers and fourteen poster presentations were given in seven formal, and one informal, sessions: Three general sessions (4 papers); Western Tight Gas (6 papers); Eastern Tight Gas (8 papers); Conventional/Speculative Resources (8 papers); and Gas to Liquids (6 papers). Individual reports are processed separately on the data bases.

  11. Fabrication of a mechanically aligned single-wafer MEMS turbine with turbocharger

    Science.gov (United States)

    Pelekies, S. O.; Schuhmann, T.; Gardner, W. G.; Camacho, A.; Protz, J. M.

    2010-10-01

    We describe the fabrication of a turbocharged, microelectromechanical system (MEMS) turbine. The turbine will be part of a standalone power unit and includes extra layers to connect the turbine to a generator. The project goal is to demonstrate the successful combination of several features, namely: silicon fusion bonding (SFB), a micro turbocharger [2], two rotors, mechanical alignment between two wafers [1], and the use of only one 5" silicon wafer. The dimension of the actual turbine casing will be 14mm. The turbine rotor will have a diameter of 8mm. Given these dimensions, MEMS processes are an adequate way to fabricate the device, but it will be necessary to stack up seven different layers to build the turbine, as it is not possible to construct it out of one thick wafer. SFB will be used for bonding because it permits the great precision necessary for high quality alignment. Yet a more precise alignment will be necessary between the layers that contain the turbine rotor, to decrease imbalance and guarantee operation at a very high rpm. To achieve these tight tolerances, a mechanical alignment feature announced by Liudi Jiang [1] is used. The alignment accuracy is expected to be around 200nm. Despite the fact that the turbine consists of multiple layers, it will be fabricated on only one silicon-on-insulator (SOI) wafer. As a result, all layers are exposed to the same process flow. The fabrication process includes MEMS technology as photolithography, nine deep reactive ion etching (DRIE) steps, and six SFB operations. A total of 14 masks are necessary for the fabrication.

  12. Molecular focusing and alignment with plasmon fields.

    Science.gov (United States)

    Artamonov, Maxim; Seideman, Tamar

    2010-12-01

    We show the possibility of simultaneously aligning molecules and focusing their center-of-mass motion near a metal nanoparticle in the field intensity gradient created by the surface plasmon enhancement of incident light. The rotational motion is described quantum mechanically while the translation is treated classically. The effects of the nanoparticle shape on the alignment and focusing are explored. Our results carry interesting implications to the field of molecular nanoplasmonics and suggest several potential applications in nanochemistry.

  13. Fiber optics welder having movable aligning mirror

    Science.gov (United States)

    Higgins, Robert W.; Robichaud, Roger E.

    1981-01-01

    A system for welding fiber optic waveguides together. The ends of the two fibers to be joined together are accurately, collinearly aligned in a vertical orientation and subjected to a controlled, diffuse arc to effect welding and thermal conditioning. A front-surfaced mirror mounted at a 45.degree. angle to the optical axis of a stereomicroscope mounted for viewing the junction of the ends provides two orthogonal views of the interface during the alignment operation.

  14. Optimal Nonlinear Filter for INS Alignment

    Institute of Scientific and Technical Information of China (English)

    赵瑞; 顾启泰

    2002-01-01

    All the methods to handle the inertial navigation system (INS) alignment were sub-optimal in the past. In this paper, particle filtering (PF) as an optimal method is used for solving the problem of INS alignment. A sub-optimal two-step filtering algorithm is presented to improve the real-time performance of PF. The approach combines particle filtering with Kalman filtering (KF). Simulation results illustrate the superior performance of these approaches when compared with extended Kalman filtering (EKF).

  15. Strategic alignment: a performance tool for SMEs

    OpenAIRE

    Jouirou, Nihel; Kalika, Michel

    2004-01-01

    The purpose of this research is to investigate whether the alignment of IT with the strategy (particularly the partnership strategy or cooperation practice) and organizational structure of an SME could have a decisive influence on its performance. We constructed a model and tested it empirically using data from 381 SMEs operating in different sectors. A multivariate perspective, modelled with structural equations, was used to test the alignment between strategy, structure and IT. The alignmen...

  16. Unscented Kalman filter for SINS alignment

    Institute of Scientific and Technical Information of China (English)

    Zhou Zhanxin; Gao Yanan; Chen Jiabin

    2007-01-01

    In order to improve the filter accuracy for the nonlinear error model of strapdown inertial navigation system (SINS) alignment, Unscented Kalman Filter (UKF) is presented for simulation with stationary base and moving base of SINS alignment.Simulation results show the superior performance of this approach when compared with classical suboptimal techniques such as extended Kalman filter in cases of large initial misalignment.The UKF has good performance in case of small initial misalignment.

  17. Aligning sourcing activities with corporate strategy

    OpenAIRE

    Buczek, Kristopher

    2014-01-01

    In this paper I set out to discover how global firms ensure that sourcing activities are aligned with corporate strategy. In order to understand this, I broke the problem down into three specific questions, which were: 1) How does strategy flow through the sourcing departments of large firms? 2) What hurdles do sourcing departments face when trying to implement corporate strategy? 3) What tools are available in improving the alignment between corporate strategies and sourcing activi...

  18. Genome Update: alignment of bacterial chromosomes

    DEFF Research Database (Denmark)

    Ussery, David; Jensen, Mette; Poulsen, Tine Rugh;

    2004-01-01

    There are four new microbial genomes listed in this month's Genome Update, three belonging to Gram-positive bacteria and one belonging to an archaeon that lives at pH 0; all of these genomes are listed in Table 1⇓. The method of genome comparison this month is that of genome alignment and......, as an example, an alignment of seven Staphylococcus aureus genomes and one Staphylococcus epidermidis genome is presented....

  19. Orthodontics Align Crooked Teeth and Boost Self-Esteem

    Science.gov (United States)

    ... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem Orthodontics print full article print this chapter email ...

  20. LHCb VELO software alignment, Part I the alignment of the VELO modules in their half boxes

    CERN Document Server

    Viret, S; Petrie, D

    2005-01-01

    Software alignment of the Vertex Locator (VELO) is a critical stage of the LHCb alignment strategy. This note presents a demonstration of a potential algorithm to satisfy the requirements of this stage. A fast track-based software alignment procedure is described. This method is based on non-iterative least squares fitting. The first step of the algorithm, the alignment of the VELO modules in their half-boxes, is fully described and results obtained with simulated events are presented and discussed. The approach described in this document, and the tools developed, are also applicable to the alignment of the other LHCb sub-systems and the global relative alignment of the sub-detectors.

  1. Can technology improve alignment during knee arthroplasty.

    Science.gov (United States)

    Thienpont, Emmanuel; Fennema, Peter; Price, Andrew

    2013-09-01

    Component malalignment remains a concern in total knee arthroplasty (TKA); therefore, a series of technologies have been developed to improve alignment. The authors conducted a systematic review to compare computer-assisted navigation with conventional instrumentation, and assess the current evidence for patient-matched instrumentation and robot-assisted implantation. An extensive search of the PubMed database for relevant meta-analyses, systematic reviews and original articles was performed, with each study scrutinised by two reviewers. Data on study characteristics and outcomes were extracted from each study and compared. In total 30 studies were included: 10 meta-analyses comparing computer-assisted navigation and conventional instrumentation, 13 studies examining patient-matched instrumentation, and seven investigating robot-assisted implantation. Computer-assisted navigation showed significant and reproducible improvements in mechanical alignment over conventional instrumentation. Patient-matched instrumentation appeared to achieve a high degree of mechanical alignment, although the majority of studies were of poor quality. The data for robot-assisted surgery was less indicative. Computer-assisted navigation improves alignment during TKA over conventional instrumentation. For patient-matched instrumentation and robot-assisted implantation, alignment benefits have not been reliably demonstrated. For all three technologies, clinical benefits cannot currently be assumed, and further studies are required. Although current technologies to improve alignment during TKA appear to result in intra-operative benefits, their clinical impact remains unclear, and surgeons should take this into account when considering their adoption.

  2. Alignments between galaxies, satellite systems and haloes

    CERN Document Server

    Shao, Shi; Frenk, Carlos S; Gao, Liang; Crain, Robert A; Schaller, Matthieu; Schaye, Joop; Theuns, Tom

    2016-01-01

    The spatial distribution of the satellite populations of the Milky Way and Andromeda are puzzling in that they are nearly perpendicular to the disks of their central galaxies. To understand the origin of such configurations we study the alignment of the central galaxy, satellite system and dark matter halo in the largest of the "Evolution and Assembly of GaLaxies and their Environments" (EAGLE) simulation. We find that centrals and their satellite systems tend to be well aligned with their haloes, with a median misalignment angle of $33^{\\circ}$ in both cases. While the centrals are better aligned with the inner $10$ kpc halo, the satellite systems are better aligned with the entire halo indicating that satellites preferentially trace the outer halo. The central - satellite alignment is weak (median misalignment angle of $52^{\\circ}$) and we find that around $20\\%$ of systems have a misalignment angle larger than $78^{\\circ}$, which is the value for the Milky Way. The central - satellite alignment is a conseq...

  3. An implicit spatial memory alignment effect.

    Science.gov (United States)

    Cerles, Mélanie; Gomez, Alice; Rousset, Stéphane

    2015-09-01

    The memory alignment effect is the advantage of reasoning from a perspective which is aligned with the frame of reference used to encode an environment in memory. It usually occurs when participants have to consciously take a perspective to perform a spatial memory task. The present experiment assesses whether the memory alignment effect can occur without requiring to consciously take a given perspective, when the misaligned perspective is only perceptively provided. In others words, does the memory alignment effect still arise when it is only implicitly prompted? Thirty participants learned a sequence of four objects' positions in a room from a north-as-up survey perspective. During the testing phase, they had to point to the direction of a target object from another object ('the reference') with a fixed north-up orientation. The background behind the reference object displayed either a uniform color (control condition) or a misaligned ground-level perspective. The latter displayed a reference object's position information which was either congruent with the studied environment (congruent misaligned condition) or incongruent (incongruent misaligned condition). Mean pointing errors were higher in the congruent misaligned condition than in the control condition, whereas the incongruent misaligned condition did not differ from the control one. The present study shows that the memory alignment effect can arise without requiring a conscious misaligned perspective taking. Moreover, the perceived misaligned perspective must share the same spatial content as the memorized spatial representation in order to induce an alignment effect. PMID:26233526

  4. Alignment of nanostructure templated from lyotropic liquid crystals in membrane preparation

    International Nuclear Information System (INIS)

    This project is developing a new class of efficient and low-cost porous membrane materials for water treatment and desalination contributing to alleviate water shortage problems in Australia. We have recently synthesized well oriented Lyotropic liquid crystal (LLC) templated membranes with an average diameter of 2mm and enhanced the retention of the original order of nanostructure after photopolymerization. We will further improve the alignment of lyotropic liquid crystal when template is formed. These LLC membranes will have great potential to significantly reduce the energy used in the desalination processes. The alignment of the LLC nanostructure is very significant and challenging. Long-range orientational order of LLC has potential applications, such as tissue engineering, gas separation, water purification, and high-density storage media. However, polydomain structures of LLC samples are randomly distributed and alignment of the lyotropic liquid crystals of the template during the membrane synthesis process will improve the performance. Magnetic field and electric field are employed to align the LLC nanostructure in nanoparticles-doped samples before polymerization. After alignment, it is expected that the nanostructure pores are well oriented in the direction perpendicular to the surface of membrane. Small Angle Scattering of X-ray and Neutron will be performed as the main means to characterize and evaluate the alignment of the LLC nanostructure.

  5. Meta-Alignment with Crumble and Prune: Partitioning very large alignment problems for performance and parallelization

    Directory of Open Access Journals (Sweden)

    Paten Benedict

    2011-05-01

    Full Text Available Abstract Background Continuing research into the global multiple sequence alignment problem has resulted in more sophisticated and principled alignment methods. Unfortunately these new algorithms often require large amounts of time and memory to run, making it nearly impossible to run these algorithms on large datasets. As a solution, we present two general methods, Crumble and Prune, for breaking a phylogenetic alignment problem into smaller, more tractable sub-problems. We call Crumble and Prune meta-alignment methods because they use existing alignment algorithms and can be used with many current alignment programs. Crumble breaks long alignment problems into shorter sub-problems. Prune divides the phylogenetic tree into a collection of smaller trees to reduce the number of sequences in each alignment problem. These methods are orthogonal: they can be applied together to provide better scaling in terms of sequence length and in sequence depth. Both methods partition the problem such that many of the sub-problems can be solved independently. The results are then combined to form a solution to the full alignment problem. Results Crumble and Prune each provide a significant performance improvement with little loss of accuracy. In some cases, a gain in accuracy was observed. Crumble and Prune were tested on real and simulated data. Furthermore, we have implemented a system called Job-tree that allows hierarchical sub-problems to be solved in parallel on a compute cluster, significantly shortening the run-time. Conclusions These methods enabled us to solve gigabase alignment problems. These methods could enable a new generation of biologically realistic alignment algorithms to be applied to real world, large scale alignment problems.

  6. Patellofemoral pain in female ballet dancers: correlation with iliotibial band tightness and tibial external rotation.

    Science.gov (United States)

    Winslow, J; Yoder, E

    1995-07-01

    Review of the literature reveals that ballet dancers have a high incidence of idiopathic patellofemoral pain. Twenty-four female ballet dancers were subjects in a study of the relationship between: 1) iliotibial band (ITB) tightness and patellofemoral pain, and 2) ITB tightness and degrees of tibial external rotation used in the dance demi-plie. Dancers were initially assessed by questionnaire to determine if any had knee pain. Twelve subjects met the study criteria for patellofemoral pain, and 12 dancers without knee pain served as controls for the study, Iliotibial band tightness was measured (Ober test), and degrees of tibial external rotation used during knee flexion (demi-plie) in standing were measured in both legs of all 24 subjects (48 legs). Chi-square analysis of the collected data revealed that there was an association between ITB tightness and patellofemoral pain in the dancers. Data analysis using the Wilcoxon Rank Sum test revealed that the degree of tibial external rotation used by dancers with iliotibial band tightness was significantly greater than those without ITB tightness. This study confirms the assumption that ITB tightness in dancers may be a contributing factor to patellofemoral pain. Follow-up study is indicated to determine if the preservation or restoration of functional ITB length is effective in the prevention and/or treatment of patellofemoral pain in ballet dancers. PMID:7550298

  7. Impact of Air Tightness on the Evaluation of Building Energy Performance in Lithuania

    Directory of Open Access Journals (Sweden)

    Jolanta Šadauskienė

    2014-08-01

    Full Text Available In order to fulfil the European Energy Performance of Buildings Directive (EPBD requirements for the reduction of energy consumption, European national requirements have been created for building envelope thermal properties and calculation methodology to determine if building energy efficiency is created. This is however not true in all methodologies. The necessity of building air tightness appears only for new A class buildings, and there are no requirements for air tightness for other building classes. Therefore, the aim of this work is to improve the methodology for the calculation of energy efficiency of buildings, while taking into account the air tightness of the buildings. In order to achieve this aim, the sum energy consumption of investigated buildings was calculated, energy efficiency classes were determined, air tightness of the buildings was measured, and reasons for insufficient air tightness were analyzed. Investigation results show that the average value of air tightness of A energy efficiency class buildings is 0.6 h−1. The results of other investigated buildings, corresponding to B and C energy efficiency classes, show insufficient air tightness (the average n50 value is 6 h−1; herewith, energy consumption for heating is higher than calculated, according to the energy efficiency methodology. This paper provides an energy performance evaluation scheme, under which performed evaluation of energy performance of buildings ensures high quality construction work, building durability, and the reliability of heat-loss calculations.

  8. In vitro cumulative gas production techniques: history, methodological considerations and challenges

    NARCIS (Netherlands)

    Rymer, C.; Huntington, J.A.; Williams, B.A.; Givens, D.I.

    2005-01-01

    Methodology used to measure in vitro gas production is reviewed to determine impacts of sources of variation on resultant gas production profiles (GPP). Current methods include measurement of gas production at constant pressure (e.g., use of gas tight syringes), a system that is inexpensive, but may

  9. Automatic laser beam alignment using blob detection for an environment monitoring spectroscopy

    Science.gov (United States)

    Khidir, Jarjees; Chen, Youhua; Anderson, Gary

    2013-05-01

    This paper describes a fully automated system to align an infra-red laser beam with a small retro-reflector over a wide range of distances. The component development and test were especially used for an open-path spectrometer gas detection system. Using blob detection under OpenCV library, an automatic alignment algorithm was designed to achieve fast and accurate target detection in a complex background environment. Test results are presented to show that the proposed algorithm has been successfully applied to various target distances and environment conditions.

  10. Symmetry Feature and Construction for the 3-Band Tight Framelets with Prescribed Properties

    Directory of Open Access Journals (Sweden)

    Jianjun Sun

    2012-01-01

    Full Text Available A construction approach for the 3-band tight wavelet frames by factorization of paraunitary matrix is developed. Several necessary constraints on the filter lengths and symmetric features of wavelet frames are investigated starting at the constructed paraunitary matrix. The matrix is a symmetric extension of the polyphase matrix corresponding to 3-band tight wavelet frames. Further, the parameterizations of 3-band tight wavelet frames with 3N+1 filter lengths are established. Examples of framelets with symmetry/antisymmetry and Sobolev exponent are computed by appropriately choosing the parameters in the scheme.

  11. State vector evolution localized over the edges of a square tight-binding lattice

    Institute of Scientific and Technical Information of China (English)

    He Liang-Ming; Shi Duan-Wen

    2009-01-01

    We study the time evolution of a state vector in a square tight-binding lattice, focusing on its evolution localized over the system surfaces. In this tight-binding lattice, the energy of atomic orbital centred at surface site is different from that at the interior (bulky) site by an energy shift U. It is shown that for the state vector initially localized on a surface, there exists an exponential law (y = aex/b + yo) determined by the absolute value of the energy shift, \\U\\, which describes the transition of the state evolving on the square tight-binding lattice, from delocalized over the whole lattice to localized over the surfaces.

  12. Proteomic and bioinformatic analysis of epithelial tight junction reveals an unexpected cluster of synaptic molecules

    Directory of Open Access Journals (Sweden)

    Tang Vivian W

    2006-12-01

    Full Text Available Abstract Background Zonula occludens, also known as the tight junction, is a specialized cell-cell interaction characterized by membrane "kisses" between epithelial cells. A cytoplasmic plaque of ~100 nm corresponding to a meshwork of densely packed proteins underlies the tight junction membrane domain. Due to its enormous size and difficulties in obtaining a biochemically pure fraction, the molecular composition of the tight junction remains largely unknown. Results A novel biochemical purification protocol has been developed to isolate tight junction protein complexes from cultured human epithelial cells. After identification of proteins by mass spectroscopy and fingerprint analysis, candidate proteins are scored and assessed individually. A simple algorithm has been devised to incorporate transmembrane domains and protein modification sites for scoring membrane proteins. Using this new scoring system, a total of 912 proteins have been identified. These 912 hits are analyzed using a bioinformatics approach to bin the hits in 4 categories: configuration, molecular function, cellular function, and specialized process. Prominent clusters of proteins related to the cytoskeleton, cell adhesion, and vesicular traffic have been identified. Weaker clusters of proteins associated with cell growth, cell migration, translation, and transcription are also found. However, the strongest clusters belong to synaptic proteins and signaling molecules. Localization studies of key components of synaptic transmission have confirmed the presence of both presynaptic and postsynaptic proteins at the tight junction domain. To correlate proteomics data with structure, the tight junction has been examined using electron microscopy. This has revealed many novel structures including end-on cytoskeletal attachments, vesicles fusing/budding at the tight junction membrane domain, secreted substances encased between the tight junction kisses, endocytosis of tight junction

  13. Installation of the light tight cover for the SSD modules (the modules are behind the aluminium plate). The silicon sensors are sensitive to light tight, so ambient light will increase the noise and may even damage them.

    CERN Multimedia

    Nooren, G.

    2004-01-01

    Installation of the light tight cover for the SSD modules (the modules are behind the aluminium plate). The silicon sensors are sensitive to light tight , so ambient light will increase the noise and may even damage them.

  14. Advances in process overlay: alignment solutions for future technology nodes

    Science.gov (United States)

    Megens, Henry; van Haren, Richard; Musa, Sami; Doytcheva, Maya; Lalbahadoersing, Sanjay; van Kemenade, Marc; Lee, Hyun-Woo; Hinnen, Paul; van Bilsen, Frank

    2007-03-01

    Semiconductor industry has an increasing demand for improvement of the total lithographic overlay performance. To improve the level of on-product overlay control the number of alignment measurements increases. Since more mask levels will be integrated, more alignment marks need to be printed when using direct-alignment (also called layer-to-layer alignment). Accordingly, the alignment mark size needs to become smaller, to fit all marks into the scribelane. For an in-direct alignment scheme, e.g. a scheme that aligns to another layer than the layer to which overlay is being measured, the number of needed alignment marks can be reduced. Simultaneously there is a requirement to reduce the size of alignment mark sub-segmentations without compromising the alignment and overlay performance. Smaller features within alignment marks can prevent processing issues like erosion, dishing and contamination. However, when the sub-segmentation size within an alignment mark becomes comparable to the critical dimension, and thus smaller than the alignment-illuminating wavelength, polarization effects might start to occur. Polarization effects are a challenge for optical alignment systems to maintain mark detectability. Nevertheless, this paper shows how to actually utilize those effects in order to obtain enhanced alignment and overlay performance to support future technology nodes. Finally, another challenge to be met for new semiconductor product technologies is the ability to align through semi-opaque materials, like for instance new hard-mask materials. Enhancement of alignment signal strength can be reached by adapting to new alignment marks that generate a higher alignment signal. This paper provides a description of an integral alignment solution that meets with these emerging customer application requirements. Complying with these requirements will significantly enhance the flexibility in production strategies while maintaining or improving the alignment and overlay

  15. Laser alignment of rotating equipment at PNL

    International Nuclear Information System (INIS)

    Lateral vibration in direct-drive equipment is usually caused by misalignment. Over the years, because of the need to improve on techniques and ways of working more efficiently, various types of alignment methods have evolved. In the beginning, craftsmen used a straight-edge scale across the coupling with a feeler gauge measuring the misalignment error. This is still preferred today for aligning small couplings. The industry has since decided that alignment of large direct-drive equipment needed a more accurate type of instrumentation. Rim and face is another of the first alignment methods and is used on all sizes of equipment. A disadvantage of the rim and face method is that in most cases the coupling has to be disassembled. This can cause alignment problems when the coupling is reassembled. Also, the rim and face method is not fast enough to work satisfactorily on alignment of thermally hot equipment. Another concern is that the coupling has to be manufactured accurately for correct rim and face readings. Reverse dial alignment is an improvement over the rim and face method, and depending on the operator's experience, this method can be very accurate. A good training program along with field experience will bring the operator to a proper level of proficiency for a successful program. A hand-held computer with reverse dial calculations in memory is a must for job efficiency. An advantage over the rim and face method is that the coupling is not disassembled and remains locked together. Reverse dial instrumentation measures from both shaft center lines, rather than the coupling surface so the machining of the coupling during manufacture is not a major concern

  16. Using Quasi-Horizontal Alignment in the absence of the actual alignment.

    Science.gov (United States)

    Banihashemi, Mohamadreza

    2016-10-01

    Horizontal alignment is a major roadway characteristic used in safety and operational evaluations of many facility types. The Highway Safety Manual (HSM) uses this characteristic in crash prediction models for rural two-lane highways, freeway segments, and freeway ramps/C-D roads. Traffic simulation models use this characteristic in their processes on almost all types of facilities. However, a good portion of roadway databases do not include horizontal alignment data; instead, many contain point coordinate data along the roadways. SHRP 2 Roadway Information Database (RID) is a good example of this type of data. Only about 5% of this geodatabase contains alignment information and for the rest, point data can easily be produced. Even though the point data can be used to extract actual horizontal alignment data but, extracting horizontal alignment is a cumbersome and costly process, especially for a database of miles and miles of highways. This research introduces a so called "Quasi-Horizontal Alignment" that can be produced easily and automatically from point coordinate data and can be used in the safety and operational evaluations of highways. SHRP 2 RID for rural two-lane highways in Washington State is used in this study. This paper presents a process through which Quasi-Horizontal Alignments are produced from point coordinates along highways by using spreadsheet software such as MS EXCEL. It is shown that the safety and operational evaluations of the highways with Quasi-Horizontal Alignments are almost identical to the ones with the actual alignments. In the absence of actual alignment the Quasi-Horizontal Alignment can easily be produced from any type of databases that contain highway coordinates such geodatabases and digital maps. PMID:27391796

  17. Using Quasi-Horizontal Alignment in the absence of the actual alignment.

    Science.gov (United States)

    Banihashemi, Mohamadreza

    2016-10-01

    Horizontal alignment is a major roadway characteristic used in safety and operational evaluations of many facility types. The Highway Safety Manual (HSM) uses this characteristic in crash prediction models for rural two-lane highways, freeway segments, and freeway ramps/C-D roads. Traffic simulation models use this characteristic in their processes on almost all types of facilities. However, a good portion of roadway databases do not include horizontal alignment data; instead, many contain point coordinate data along the roadways. SHRP 2 Roadway Information Database (RID) is a good example of this type of data. Only about 5% of this geodatabase contains alignment information and for the rest, point data can easily be produced. Even though the point data can be used to extract actual horizontal alignment data but, extracting horizontal alignment is a cumbersome and costly process, especially for a database of miles and miles of highways. This research introduces a so called "Quasi-Horizontal Alignment" that can be produced easily and automatically from point coordinate data and can be used in the safety and operational evaluations of highways. SHRP 2 RID for rural two-lane highways in Washington State is used in this study. This paper presents a process through which Quasi-Horizontal Alignments are produced from point coordinates along highways by using spreadsheet software such as MS EXCEL. It is shown that the safety and operational evaluations of the highways with Quasi-Horizontal Alignments are almost identical to the ones with the actual alignments. In the absence of actual alignment the Quasi-Horizontal Alignment can easily be produced from any type of databases that contain highway coordinates such geodatabases and digital maps.

  18. Empirical tight-binding modeling of ordered and disordered semiconductor structures; Empirische Tight-Binding-Modellierung geordneter und ungeordneter Halbleiterstrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Mourad, Daniel

    2010-11-30

    In this thesis, we investigate the electronic and optical properties of pure as well as of substitutionally alloyed II-VI and III-V bulk semiconductors and corresponding semiconductor quantum dots by means of an empirical tight-binding (TB) model. In the case of the alloyed systems of the type A{sub x}B{sub 1-x}, where A and B are the pure compound semiconductor materials, we study the influence of the disorder by means of several extensions of the TB model with different levels of sophistication. Our methods range from rather simple mean-field approaches (virtual crystal approximation, VCA) over a dynamical mean-field approach (coherent potential approximation, CPA) up to calculations where substitutional disorder is incorporated on a finite ensemble of microscopically distinct configurations. In the first part of this thesis, we cover the necessary fundamentals in order to properly introduce the TB model of our choice, the effective bond-orbital model (EBOM). In this model, one s- and three p-orbitals per spin direction are localized on the sites of the underlying Bravais lattice. The matrix elements between these orbitals are treated as free parameters in order to reproduce the properties of one conduction and three valence bands per spin direction and can then be used in supercell calculations in order to model mixed bulk materials or pure as well as mixed quantum dots. Part II of this thesis deals with unalloyed systems. Here, we use the EBOM in combination with configuration interaction calculations for the investigation of the electronic and optical properties of truncated pyramidal GaN quantum dots embedded in AlN with an underlying zincblende structure. Furthermore, we develop a parametrization of the EBOM for materials with a wurtzite structure, which allows for a fit of one conduction and three valence bands per spin direction throughout the whole Brillouin zone of the hexagonal system. In Part III, we focus on the influence of alloying on the electronic

  19. New alignment marks for improved measurement maturity

    Science.gov (United States)

    Weidenmueller, U.; Alves, H.; Schnabel, B.; Icard, B.; Pain, L.; Le Denmat, J.-C.; Manakli, S.; Pradelles, J.

    2008-04-01

    With shrinking dimensions in the semiconductor industry the lithographic demands are exceeding the parameters of the standard optical lithography. Electron beam direct write (EBDW) presents a good solution to overcome these limits and to successfully use this technology in R&D as well as in prototyping and some niche applications. For the industrial application of EBDW an alignment strategy adapted to the industrial standards is required to be compatible with optical lithography. In this context the crucial factor is the overlay performance, i.e. the maturity of the alignment strategy under different process conditions. New alignment marks improve the alignment repeatability and increase the window of the signal-to-noise ratio towards smaller or noisier signals. Particularly the latter has proved to be a major contribution to a higher maturity of the alignment. A comparison between the double cross and the new Barker mark type is presented in this paper. Furthermore, the mark reading repeatability and the final overlay results achieved are discussed.

  20. Enabling Process Alignment for IT Entrepreneurship

    Directory of Open Access Journals (Sweden)

    Sonia D. Bot

    2012-11-01

    Full Text Available All firms use information technology (IT. Larger firms have IT organizations whose business function is to supply and manage IT infrastructure and applications to support the firm's business objectives. Regardless of whether the IT function has been outsourced or is resident within a firm, the objectives of the IT organization must be aligned to the strategic needs of the business. It is often a challenge to balance the demand for IT against the available supply within the firm. Most IT organizations have little capacity to carry out activities that go beyond the incremental ones that are needed to run the immediate needs of the business. A process-ambidexterity framework for IT improves the IT organization's entrepreneurial ability, which in turn, better aligns the IT function with the business functions in the firm. Process ambidexterity utilizes both process alignment and process adaptability. This article presents a framework for process alignment in IT. This is useful for understanding how the processes in Business Demand Management, a core component of the process-ambidexterity framework for IT, relate to those in IT Governance and IT Supply Chain Management. The framework is presented through three lenses (governance, business, and technology along with real-world examples from major firms in the USA. Enabling process alignment in the IT function, and process ambidexterity overall, benefits those who govern IT, the executives who lead IT, as well as their peers in the business functions that depend on IT.