WorldWideScience

Sample records for mean-spin barrier bump

  1. Under bump metallurgy study for Pb-free bumping

    Science.gov (United States)

    Jang, Se-Young; Wolf, Juergen; Paik, Kyung-Wook

    2002-05-01

    The demand for Pb-free and high-density interconnection technology is rapidly growing. The electroplating-bumping method is a good approach to meet finepitch requirements, especially for high-volume production, because to volume change of patterned-solder bumps during reflow is not so large compared with the stencil-printing method. This paper proposes a Sn/3.5 Ag Pb-free electroplating-bumping process for high-density Pb-free interconnects. It was found that a plated Sn/Ag bump becomes Sn/Ag/Cu by reflowing when Cu containing under bump metallurgy (UBM) is used. Another important issue for future flip-chip interconnects is to optimize the UBM system for high-density and Pb-free solder bumps. In this work, four UBM systems, sputtered TiW 0.2 µm/Cu 0.3 µm/electroplated Cu 5 µm, sputtered Cr 0.15 µm/Cr-Cu 0.3 µm/Cu 0.8 µm, sputtered NiV 0.2 µm/Cu 0.8 µm, and sputtered TiW 0.2 µm/NiV 0.8 µm, were investigated for interfacial reaction with electroplated Pb/63Sn and Sn/3.5Ag solder bumps. Both Cu-Sn and Ni-Sn intermetallic compound (IMC) growth were observed to spall-off from the UBM/solder interface when the solder-wettable layer is consumed during a liquid-state “reflow” process. This IMC-spalling mechanism differed depending on the barrier layer material.

  2. Condensation on Slippery Asymmetric Bumps

    CERN Document Server

    Park, Kyoo-Chul; He, Neil; Aizenberg, Joanna

    2015-01-01

    Bumps are omnipresent from human skin to the geological structures on planets, which offer distinct advantages in numerous phenomena including structural color, drag reduction, and extreme wettability. Although the topographical parameters of bumps such as radius of curvature of convex regions significantly influence various phenomena including anti-reflective structures and contact time of impacting droplets, the effect of the detailed bump topography on growth and transport of condensates have not been clearly understood. Inspired by the millimetric bumps of the Namib Desert beetle, here we report the identified role of radius of curvature and width of bumps with homogeneous surface wettability in growth rate, coalescence and transport of water droplets. Further rational design of asymmetric convex topography and synergetic combination with slippery coating simultaneously enable self-transport, leading to unseen five-fold higher growth rate and an order of magnitude faster shedding time of droplets compared...

  3. Recent advances in understanding the reminiscence bump

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Rubin, David C.

    2016-01-01

    the bump obtained when important memories are requested. The bump obtained in response to odor cues is even earlier. This variation in the size and temporal location of the reminiscence bump argues for theories based primarily on retrieval rather than encoding and retention, which most current theories...... stress. Furthermore, it points to the need to develop theories of autobiographical memory that account for this flexibility in the memories retrieved....

  4. Condensation on Slippery Asymmetric Bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Aizenberg, Joanna

    2016-11-01

    Controlling dropwise condensation by designing surfaces that enable droplets to grow rapidly and be shed as quickly as possible is fundamental to water harvesting systems, thermal power generation, distillation towers, etc. However, cutting-edge approaches based on micro/nanoscale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach based on principles derived from Namib desert beetles, cacti, and pitcher plants that synergistically couples both aspects of condensation and outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle's bump geometry in promoting condensation, we show how to maximize vapor diffusion flux at the apex of convex millimetric bumps by optimizing curvature and shape. Integrating this apex geometry with a widening slope analogous to cactus spines couples rapid drop growth with fast directional transport, by creating a free energy profile that drives the drop down the slope. This coupling is further enhanced by a slippery, pitcher plant-inspired coating that facilitates feedback between coalescence-driven growth and capillary-driven motion. We further observe an unprecedented six-fold higher exponent in growth rate and much faster shedding time compared to other surfaces. We envision that our fundamental understanding and rational design strategy can be applied to a wide range of phase change applications.

  5. Process for Patterning Indium for Bump Bonding

    Science.gov (United States)

    Denis, Kevin

    2012-01-01

    An innovation was created for the Cosmology Large Angular Scale Surveyor for integration of low-temperature detector chips with a silicon backshort and a silicon photonic choke through flipchip bonding. Indium bumps are typically patterned using liftoff processes, which require thick resist. In some applications, it is necessary to locate the bumps close to high-aspect-ratio structures such as wafer through-holes. In those cases, liftoff processes are challenging, and require complicated and time-consuming spray coating technology if the high-aspect-ratio structures are delineated prior to the indium bump process. Alternatively, processing the indium bumps first is limited by compatibility of the indium with subsequent processing. The present invention allows for locating bumps arbitrarily close to multiple-level high-aspect-ratio structures, and for indium bumps to be formed without liftoff resist. The process uses the poor step coverage of indium deposited on a silicon wafer that has been previously etched to delineate the location of the indium bumps. The silicon pattern can be processed through standard lithography prior to adding the high-aspect-ratio structures. Typically, high-aspectratio structures require a thick resist layer so this layer can easily cover the silicon topography. For multiple levels of topography, the silicon can be easily conformally coated through standard processes. A blanket layer of indium is then deposited onto the full wafer; bump bonding only occurs at the high points of the topography.

  6. Haglund syndrome with pump bump.

    Science.gov (United States)

    Kucuksen, Sami; Karahan, Ali Yavuz; Erol, Kemal

    2012-01-01

    Haglund's syndrome, which is an inflammation of the bursa and a bony enlargement on the back of the heel that most often leads to painful bursitis, is a rare cause of retrocalcaneal pain. The clinical diagnosis is often confusing as the clinical picture may mimic other causes of hindfoot pain such as isolated retrocalcaneal bursitis or hindfoot involvement from more systemic disorders such as seronegative spondyloarthropathies (Reiter's syndrome, ankylosing spondylitis) or rheumatoid arthritis. This report is of a 60-year-old woman with a painful swelling of the right heel, who was diagnosed with Haglund syndrome. The characteristic clinical photograph (showing the prominent 'pump bump'), radiographical and magnetic resonance imaging features are presented.

  7. Condensation on slippery asymmetric bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Grinthal, Alison; He, Neil; Fox, David; Weaver, James C.; Aizenberg, Joanna

    2016-03-01

    Controlling dropwise condensation is fundamental to water-harvesting systems, desalination, thermal power generation, air conditioning, distillation towers, and numerous other applications. For any of these, it is essential to design surfaces that enable droplets to grow rapidly and to be shed as quickly as possible. However, approaches based on microscale, nanoscale or molecular-scale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach—based on principles derived from Namib desert beetles, cacti, and pitcher plants—that synergistically combines these aspects of condensation and substantially outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle’s bumpy surface geometry in promoting condensation, and using theoretical modelling, we show how to maximize vapour diffusion fluxat the apex of convex millimetric bumps by optimizing the radius of curvature and cross-sectional shape. Integrating this apex geometry with a widening slope, analogous to cactus spines, directly couples facilitated droplet growth with fast directional transport, by creating a free-energy profile that drives the droplet down the slope before its growth rate can decrease. This coupling is further enhanced by a slippery, pitcher-plant-inspired nanocoating that facilitates feedback between coalescence-driven growth and capillary-driven motion on the way down. Bumps that are rationally designed to integrate these mechanisms are able to grow and transport large droplets even against gravity and overcome the effect of an unfavourable temperature gradient. We further observe an unprecedented sixfold-higher exponent of growth rate, faster onset, higher steady-state turnover rate, and a greater volume of water collected compared to other surfaces. We envision that this fundamental understanding and rational design strategy can be

  8. Wandering bumps in stochastic neural fields

    CERN Document Server

    Kilpatrick, Zachary P

    2012-01-01

    We study the effects of noise on stationary pulse solutions (bumps) in spatially extended neural fields. The dynamics of a neural field is described by an integrodifferential equation whose integral term characterizes synaptic interactions between neurons in different spatial locations of the network. Translationally symmetric neural fields support a continuum of stationary bump solutions, which may be centered at any spatial location. Random fluctuations are introduced by modeling the system as a spatially extended Langevin equation whose noise term we take to be multiplicative or additive. For nonzero noise, these bumps are shown to wander about the domain in a purely diffusive way. We can approximate the effective diffusion coefficient using a small noise expansion. Upon breaking the (continuous) translation symmetry of the system using a spatially heterogeneous inputs or synapses, bumps in the stochastic neural field can become temporarily pinned to a finite number of locations in the network. In the case...

  9. Recent advances in understanding the reminiscence bump

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Rubin, David C.

    2016-01-01

    The reminiscence bump is the increased proportion of autobiographical memories from youth and early adulthood observed in adults over 40. It is one of the most robust findings in autobiographical-memory research. Although described as a single period from which there are more memories, a recent...... the bump obtained when important memories are requested. The bump obtained in response to odor cues is even earlier. This variation in the size and temporal location of the reminiscence bump argues for theories based primarily on retrieval rather than encoding and retention, which most current theories...... stress. Furthermore, it points to the need to develop theories of autobiographical memory that account for this flexibility in the memories retrieved....

  10. The reminiscence bump in autobiographical memory and for public events

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    for autobiographical memories. For most important memories, we found a bump from ages 20 to 29 in autobiographical memory, but little discernible age pattern for public events. Rather, specific public events (e.g., the Fall of the Berlin Wall) dominated recall, producing a chronological distribution characterised......The reminiscence bump has been found for both autobiographical memories and memories of public events. However, there have been few comparisons of the bump across each type of event. In the current study, therefore, we compared the bump for autobiographical memories versus the bump for memories...... of public events. We did so between-subjects, through two cueing methods administered within-subjects, the cue word method and the important memories method. For word-cued memories, we found a similar bump from ages 5 to 19 for both types of memories. However, the bump was more pronounced...

  11. The reminiscence bump in autobiographical memory and for public events

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    The reminiscence bump has been found for both autobiographical memories and memories of public events. However, there have been few comparisons of the bump across each type of event. In the current study, therefore, we compared the bump for autobiographical memories versus the bump for memories...... of public events. We did so between-subjects, through two cueing methods administered within-subjects, the cue word method and the important memories method. For word-cued memories, we found a similar bump from ages 5 to 19 for both types of memories. However, the bump was more pronounced...... for autobiographical memories. For most important memories, we found a bump from ages 20 to 29 in autobiographical memory, but little discernible age pattern for public events. Rather, specific public events (e.g., the Fall of the Berlin Wall) dominated recall, producing a chronological distribution characterised...

  12. Quasars and the Big Blue Bump

    OpenAIRE

    Shang, Zhaohui; Brotherton, Michael S.; Green, Richard F.; Kriss, Gerard A.; Scott, Jennifer; Quijano, Jessica Kim; Blaes, Omer; Hubeny, Ivan; Hutchings, John; Kaiser, Mary Elizabeth; Koratkar, Anuradha; Oegerle, William; Zheng, Wei

    2004-01-01

    We investigate the ultraviolet-to-optical spectral energy distributions (SEDs) of 17 active galactic nuclei (AGNs) using quasi-simultaneous spectrophotometry spanning 900-9000 Angstrom (rest frame). We employ data from the Far Ultraviolet Spectroscopic Explorer (FUSE), the Hubble Space Telescope (HST), and the 2.1-meter telescope at Kitt Peak National Observatory (KPNO). Taking advantage of the short-wavelength coverage, we are able to study the so-called "big blue bump," the region where the...

  13. Extended intrinsic mean spin tensor for turbulence modelling in non-inertial frame of reference

    Institute of Scientific and Technical Information of China (English)

    HUANG Yu-ning; MA Hui-yang

    2008-01-01

    We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference.It is described by the Euclidean group of transformations and,in particular,its significance and importance in the approach of the algebraic Reynolds stress modelling,such as in a nonlinear K-εmodel.To this end and for illustration of the effect of extended intrinsic spin tensor on turbulence modelling,we examine several recently developed nonlinear K-ε models and compare their performance in predicting the homogeneous turbulent shear flow in a rotating frame of reference with LES data.Our results and analysis indicate that,only if the deficiencies of these models and the like be well understood and properly corrected,may in the near future,more sophisticated nonlinear K-ε models be 0eveloped to better predict complex turbulent flows in a non-inertial frame of reference.

  14. Subdiffusive dynamics of bump attractors: mechanisms and functional roles.

    Science.gov (United States)

    Qi, Yang; Breakspear, Michael; Gong, Pulin

    2015-02-01

    Bump attractors are localized activity patterns that can self-sustain after stimulus presentation, and they are regarded as the neural substrate for a host of perceptual and cognitive processes. One of the characteristic features of bump attractors is that they are neutrally stable, so that noisy inputs cause them to drift away from their initial locations, severely impairing the accuracy of bump location-dependent neural coding. Previous modeling studies of such noise-induced drifting activity of bump attractors have focused on normal diffusive dynamics, often with an assumption that noisy inputs are uncorrelated. Here we show that long-range temporal correlations and spatial correlations in neural inputs generated by multiple interacting bumps cause them to drift in an anomalous subdiffusive way. This mechanism for generating subdiffusive dynamics of bump attractors is further analyzed based on a generalized Langevin equation. We demonstrate that subdiffusive dynamics can significantly improve the coding accuracy of bump attractors, since the variance of the bump displacement increases sublinearly over time and is much smaller than that of normal diffusion. Furthermore, we reanalyze existing psychophysical data concerning the spread of recalled cue position in spatial working memory tasks and show that its variance increases sublinearly with time, consistent with subdiffusive dynamics of bump attractors. Based on the probability density function of bump position, we also show that the subdiffusive dynamics result in a long-tailed decay of firing rate, greatly extending the duration of persistent activity.

  15. The reminiscence bump reconsidered: Children's prospective life stories show a bump in young adulthood

    DEFF Research Database (Denmark)

    Bohn, Annette; Berntsen, Dorthe

    2011-01-01

    Abstract The reminiscence bump—the reporting of more memories from young adulthood than from other stages of life—is considered a hallmark of autobiographical memory research. The most prevalent explanations for this effect assume that events in young adulthood are favored because of the way...... showed a clear bump in young adulthood. In Study 2, children were prompted by word cues to write down events from their future lives. The events generated consisted mostly of non-life-script events, and those events did not show a bump in young adulthood. Our findings challenge prevailing explanations...

  16. Design of Bump Magnet of CSR

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Four bumpers are required for the injection and extraction of CSR. The parameters of the bumpers are shown in table 1. Because of the steep raising and falling time and therefore the inductance of the magnet should be as small as possible, so the material of the magnet cores must be ferrite. And in order to reduce the cost of the bump magnet, the cross-section of the four ferrite cores was designed as the same, as shown in Fig.1.It is very similar to the lamination of the H-type dipole. And Fig.2 is the...

  17. ICHEP 2016: to b(ump) or not to b(ump)

    CERN Multimedia

    2016-01-01

    This week I’m in Chicago for the 38th International Conference on High Energy Physics, ICHEP 2016, hosted this year by the US particle physics community. While it became clear at the conference that the famous 750 GeV bump has flatlined, there’s been a wealth of physics from CERN and around the world.   Everyone in their heart felt that the bump would turn out to be no more than a statistical fluctuation, while secretly hoping that it would be something new. Even the designer of the ICHEP 2016 logo cleverly hid a bump with a subtle question mark in the Chicago skyline – appropriately enough in Anish Kapoor’s mysterious ‘Cloud Gate’ sculpture. That question mark has now been resolved. Kapoor’s sculpture returns to being just that, and the search for new physics goes on albeit further constrained as theorists revealed in the 400+ papers in the wake of the bump discussion. The highlight from CERN was undoubtedly the spectacular pe...

  18. NSRL Extraction Bump Control in the Booster

    Energy Technology Data Exchange (ETDEWEB)

    Brennan,L.

    2008-10-01

    Due to inadequacies in the user interface of the booster orbit control system, a number of new tools were developed. The first priority was an accurate calculation of the winding currents given specific displacements at each extraction septa. Next, the physical limits of the power supplies ({+-}600 amps) needed to be taken into account. In light of this limit, a system is developed that indicates to the user what the allowed values of one bump parameter are once the other two have been specified. Finally, techniques are developed to account for the orbit behavior once power supplies are requested to exceed their {+-}600 amp limit. This includes a recalculation of bump parameters and a calculation of the amplitude of the residuals. Following this, possible areas for further development are outlined. These techniques were computationally developed in Mathematica and tested in the Methodical Accelerator Design (MAD) program before they were implemented into the control system. At the end, a description of the implementation of these techniques in a new interface is described. This includes a depiction of the appearance and functionality of the graphical user interface, a description of the input and output flow, and an outline of how each important calculation is performed.

  19. Cascading reminiscence bumps in popular music.

    Science.gov (United States)

    Krumhansl, Carol Lynne; Zupnick, Justin Adam

    2013-10-01

    Autobiographical memories are disproportionately recalled for events in late adolescence and early adulthood, a phenomenon called the reminiscence bump. Previous studies on music have found autobiographical memories and life-long preferences for music from this period. In the present study, we probed young adults' personal memories associated with top hits over 5-and-a-half decades, as well as the context of their memories and their recognition of, preference for, quality judgments of, and emotional reactions to that music. All these measures showed the typical increase for music released during the two decades of their lives. Unexpectedly, we found that the same measures peaked for the music of participants' parents' generation. This finding points to the impact of music in childhood and suggests that these results reflect the prevalence of music in the home environment. An earlier peak occurred for 1960s music, which may be explained by its quality or by its transmission through two generations. We refer to this pattern of musical cultural transmission over generations as cascading reminiscence bumps.

  20. Decomposing the sales promotion bump with store data

    NARCIS (Netherlands)

    van Heerde, H.J.; Leeflang, P.S.H.; Wittink, D.R.

    2004-01-01

    Sales promotions generate substantial short-term sales increases. To determine whether the sales promotion bump is truly beneficial from a managerial perspective, we propose a system of store-level regression models that decomposes the sales promotion bump into three parts: cross-brand effects (seco

  1. Decomposing the sales promotion bump with store data

    NARCIS (Netherlands)

    van Heerde, H.J.; Leeflang, P.S.H.; Wittink, D.R.

    2004-01-01

    Sales promotions generate substantial short-term sales increases. To determine whether the sales promotion bump is truly beneficial from a managerial perspective, we propose a system of store-level regression models that decomposes the sales promotion bump into three parts: cross-brand effects

  2. Two-Step Plasma Process for Cleaning Indium Bonding Bumps

    Science.gov (United States)

    Greer, Harold F.; Vasquez, Richard P.; Jones, Todd J.; Hoenk, Michael E.; Dickie, Matthew R.; Nikzad, Shouleh

    2009-01-01

    A two-step plasma process has been developed as a means of removing surface oxide layers from indium bumps used in flip-chip hybridization (bump bonding) of integrated circuits. The two-step plasma process makes it possible to remove surface indium oxide, without incurring the adverse effects of the acid etching process.

  3. Bump Bonding Using Metal-Coated Carbon Nanotubes

    Science.gov (United States)

    Lamb, James L.; Dickie, Matthew R.; Kowalczyk, Robert S.; Liao, Anna; Bronikowski, Michael J.

    2012-01-01

    Bump bonding hybridization techniques use arrays of indium bumps to electrically and mechanically join two chips together. Surface-tension issues limit bump sizes to roughly as wide as they are high. Pitches are limited to 50 microns with bumps only 8-14 microns high on each wafer. A new process uses oriented carbon nanotubes (CNTs) with a metal (indium) in a wicking process using capillary actions to increase the aspect ratio and pitch density of the connections for bump bonding hybridizations. It merges the properties of the CNTs and the metal bumps, providing enhanced material performance parameters. By merging the bumps with narrow and long CNTs oriented in the vertical direction, higher aspect ratios can be obtained if the metal can be made to wick. Possible aspect ratios increase from 1:1 to 20:1 for most applications, and to 100:1 for some applications. Possible pitch density increases of a factor of 10 are possible. Standard capillary theory would not normally allow indium or most other metals to be drawn into the oriented CNTs, because they are non-wetting. However, capillary action can be induced through the ability to fabricate oriented CNT bundles to desired spacings, and the use of deposition techniques and temperature to control the size and mobility of the liquid metal streams and associated reservoirs. This hybridization of two technologies (indium bumps and CNTs) may also provide for some additional benefits such as improved thermal management and possible current density increases.

  4. Flip chip bumping technology-Status and update

    Energy Technology Data Exchange (ETDEWEB)

    Juergen Wolf, M. [Fraunhofer IZM, Gustav-Meyer-Allee 25, 13355 Berlin (Germany)]. E-mail: juergen.Wolf@izm.fraunhofer.de; Engelmann, Gunter [Fraunhofer IZM, Gustav-Meyer-Allee 25, 13355 Berlin (Germany); Dietrich, Lothar [Fraunhofer IZM, Gustav-Meyer-Allee 25, 13355 Berlin (Germany); Reichl, Herbert [Fraunhofer IZM, Gustav-Meyer-Allee 25, 13355 Berlin (Germany)

    2006-09-01

    Flip chip technology is a key driver for new complex system architectures and high-density packaging, e.g. sensor or pixel devices. Bumped wafers/dice as key elements become very important in terms of general availability at low cost, high yield and quality level. Today, different materials, e.g. Au, Ni, AuSn, SnAg, SnAgCu, SnCu, etc., are used for flip chip interconnects and different bumping approaches are available. Electroplating is the technology of choice for high-yield wafer bumping for small bump sizes and pitches. Lead-free solder bumps require an increase in knowledge in the field of under bump metallization (UBM) and the interaction of bump and substrate metallization, the formation and growth of intermetallic compounds (IMCs) during liquid- and solid-phase reactions. Results of a new bi-layer UBM of Ni-Cu which is especially designed for small-sized lead-free solder bumps will be discussed.

  5. Critical Cleaning Requirements for Back End Wafer Bumping Processes

    Energy Technology Data Exchange (ETDEWEB)

    Bixenman, M. [Kyzen Corporation (United States)

    2000-04-24

    As integrated circuits become more complex, the number of I/O connections per chip grow. Conventional wire-bonding, lead-frame mounting techniques are unable to keep up. The space saved by shrinking die size is lost when the die is packages in a huge device with hundreds of leads. The solution is bumps; hold, conductive adhesive, but most importantly solder bumps. Virtually every semiconductor manufacturer in the world is using or planning to use bump technology for their larger and more complex devices. Several wafer-bumping processes used in the manufacture of bumped wafer. Some of the more popular techniques are evaporative, stencil or screen printing, electroplating, electroless nickel, solder jetting, stud bumping, decal transfer, punch and die, solder injection or extrusion, tacky dot process and ball placement. This paper will discuss the process steps for bumping wafers using these techniques. Critical cleaning is a requirement for each of these processes. Key contaminants that require removal are photoresist and flux residue. Removal of these contaminants requires wet processes, which will not attack, wafer metallization or passivation. Research gas focused on enhanced cleaning solutions that meet this critical cleaning solutions that meet this critical cleaning requirement. Process parameters defining time, temperature, solvency and impingement energy required to solvate and remove residues from bumped wafers will be presented herein. (author). 9 refs.

  6. On applying the extended intrinsic mean spin tensor to modelling the turbulence in non-inertial frames of reference

    Institute of Scientific and Technical Information of China (English)

    HUANG YuNing; MA HuiYang; XU JingLei

    2008-01-01

    Modelling the turbulent flows in non-inertial frames of reference has long been a challenging task. Recently we introduced the notion of the "extended intrinsic mean spin tensor" for turbulence modelling and pointed out that, when applying the Reynolds stress models developed in the inertial frame of reference to model-ling the turbulence in a non-inertial frame of reference, the mean spin tensor should be replaced by the extended intrinsic mean spin tensor to correctly account for the rotation effects induced by the non-inertial frame of reference, to conform in phys-ics with the Reynolds stress transport equation. To exemplify the approach, we conducted numerical simulations of the fully developed turbulent channel flow in a rotating frame of reference by employing four non-linear K-εmodels. Our numerical results based on this approach at a wide range of Reynolds and Rossby numbers evince that, among the models tested, the non-linear K-ε model of Huang and Ma and the non-linear K-ε model of Craft, Launder and Suga can better capture the rotation effects and the resulting influence on the structures of turbulence, and therefore are satisfactorily applied to dealing with the turbulent flows of practical interest in engineering. The general approach worked out in this paper is also ap-plied to the second-moment closure and the large-eddy simulation of turbulence.

  7. On applying the extended intrinsic mean spin tensor to modelling the turbulence in non-inertial frames of reference

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Modelling the turbulent flows in non-inertial frames of reference has long been a challenging task. Recently we introduced the notion of the "extended intrinsic mean spin tensor" for turbulence modelling and pointed out that, when applying the Reynolds stress models developed in the inertial frame of reference to model-ling the turbulence in a non-inertial frame of reference, the mean spin tensor should be replaced by the extended intrinsic mean spin tensor to correctly account for the rotation effects induced by the non-inertial frame of reference, to conform in phys-ics with the Reynolds stress transport equation. To exemplify the approach, we conducted numerical simulations of the fully developed turbulent channel flow in a rotating frame of reference by employing four non-linear K-ε models. Our numerical results based on this approach at a wide range of Reynolds and Rossby numbers evince that, among the models tested, the non-linear K-ε model of Huang and Ma and the non-linear K-ε model of Craft, Launder and Suga can better capture the rotation effects and the resulting influence on the structures of turbulence, and therefore are satisfactorily applied to dealing with the turbulent flows of practical interest in engineering. The general approach worked out in this paper is also ap-plied to the second-moment closure and the large-eddy simulation of turbulence.

  8. Optimization of Indium Bump Morphology for Improved Flip Chip Devices

    Science.gov (United States)

    Jones, Todd J.; Nikzad, Shouleh; Cunningham, Thomas J.; Blazejewski, Edward; Dickie, Matthew R.; Hoenk, Michael E.; Greer, Harold F.

    2011-01-01

    Flip-chip hybridization, also known as bump bonding, is a packaging technique for microelectronic devices that directly connects an active element or detector to a substrate readout face-to-face, eliminating the need for wire bonding. In order to make conductive links between the two parts, a solder material is used between the bond pads on each side. Solder bumps, composed of indium metal, are typically deposited by thermal evaporation onto the active regions of the device and substrate. While indium bump technology has been a part of the electronic interconnect process field for many years and has been extensively employed in the infrared imager industry, obtaining a reliable, high-yield process for high-density patterns of bumps can be quite difficult. Under the right conditions, a moderate hydrogen plasma exposure can raise the temperature of the indium bump to the point where it can flow. This flow can result in a desirable shape where indium will efficiently wet the metal contact pad to provide good electrical contact to the underlying readout or imager circuit. However, it is extremely important to carefully control this process as the intensity of the hydrogen plasma treatment dramatically affects the indium bump morphology. To ensure the fine-tuning of this reflow process, it is necessary to have realtime feedback on the status of the bumps. With an appropriately placed viewport in a plasma chamber, one can image a small field (a square of approximately 5 millimeters on each side) of the bumps (10-20 microns in size) during the hydrogen plasma reflow process. By monitoring the shape of the bumps in real time using a video camera mounted to a telescoping 12 magnifying zoom lens and associated optical elements, an engineer can precisely determine when the reflow of the bumps has occurred, and can shut off the plasma before evaporation or de-wetting takes place.

  9. Bump in the blue axion isocurvature spectrum

    Science.gov (United States)

    Chung, Daniel J. H.; Upadhye, Amol

    2017-01-01

    Blue axion isocurvature perturbations are both theoretically well motivated and interesting from a detectability perspective. These power spectra generically have a break from the blue region to a flat region. Previous investigations of the power spectra were analytic, which left a gap in the predicted spectrum in the break region due to the nonapplicability of the used analytic techniques. We therefore compute the isocurvature spectrum numerically for an explicit supersymmetric axion model. We find a bump that enhances the isocurvature signal for this class of scenarios. A fitting function of three parameters is constructed that fits the spectrum well for the particular axion model we study. This fitting function should be useful for blue isocurvature signal hunting in data and making experimental sensitivity forecasts.

  10. Bump-hunting in LHC ttbar events

    CERN Document Server

    Czakon, Michal; Mitov, Alexander

    2016-01-01

    We demonstrate that a purposefully normalised NNLO top pair invariant mass differential spectrum can have very small theoretical uncertainty and, in particular, a small sensitivity to the top quark mass. Such observable can thus be a very effective bump-hunting tool for resonances decaying to top pair events during LHC Run II and beyond. To illustrate how the approach works, we concentrate on one specific example of current interest, namely, the possible 750 GeV di-gamma excess resonance Phi. Considering only theoretical uncertainties, we demonstrate that it is possible to distinguish pp -> Phi -> tt signals studied in the recent literature [Hespel, Maltoni and Vryonidou, arXiv:1606.04149] from the pure SM background with very high significance. Alternatively, in case of non-observation, a strong upper limit on the decay rate Phi -> tt can be placed.

  11. Bumped-Kinase Inhibitors for Cryptosporidiosis Therapy.

    Science.gov (United States)

    Hulverson, Matthew A; Vinayak, Sumiti; Choi, Ryan; Schaefer, Deborah A; Castellanos-Gonzalez, Alejandro; Vidadala, Rama S R; Brooks, Carrie F; Herbert, Gillian T; Betzer, Dana P; Whitman, Grant R; Sparks, Hayley N; Arnold, Samuel L M; Rivas, Kasey L; Barrett, Lynn K; White, A Clinton; Maly, Dustin J; Riggs, Michael W; Striepen, Boris; Van Voorhis, Wesley C; Ojo, Kayode K

    2017-04-15

    Bumped kinase inhibitors (BKIs) of Cryptosporidium parvum calcium-dependent protein kinase 1 (CpCDPK1) are leading candidates for treatment of cryptosporidiosis-associated diarrhea. Potential cardiotoxicity related to anti-human ether-à-go-go potassium channel (hERG) activity of the first-generation anti-Cryptosporidium BKIs triggered further testing for efficacy. A luminescence assay adapted for high-throughput screening was used to measure inhibitory activities of BKIs against C. parvum in vitro. Furthermore, neonatal and interferon γ knockout mouse models of C. parvum infection identified BKIs with in vivo activity. Additional iterative experiments for optimum dosing and selecting BKIs with minimum levels of hERG activity and frequencies of other safety liabilities included those that investigated mammalian cell cytotoxicity, C. parvum proliferation inhibition in vitro, anti-human Src inhibition, hERG activity, in vivo pharmacokinetic data, and efficacy in other mouse models. Findings of this study suggest that fecal concentrations greater than parasite inhibitory concentrations correlate best with effective therapy in the mouse model of cryptosporidiosis, but a more refined model for efficacy is needed. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  12. Quasars and the Big Blue Bump

    CERN Document Server

    Shang, Z; Green, R F; Kriss, G A; Scott, J; Quijano, J K; Blaes, Omer M; Hubeny, I; Hutchings, J B; Kaiser, M E; Koratkar, A; Oegerle, W; Zheng, W; Shang, Zhaohui; Brotherton, Michael S.; Green, Richard F.; Kriss, Gerard A.; Scott, Jennifer; Quijano, Jessica Kim; Blaes, Omer; Hubeny, Ivan; Hutchings, John; Kaiser, Mary Elizabeth; Koratkar, Anuradha; Oegerle, William; Zheng, Wei

    2004-01-01

    We investigate the ultraviolet-to-optical spectral energy distributions (SEDs) of 17 active galactic nuclei (AGNs) using quasi-simultaneous spectrophotometry spanning 900-9000 Angstrom (rest frame). We employ data from the Far Ultraviolet Spectroscopic Explorer (FUSE), the Hubble Space Telescope (HST), and the 2.1-meter telescope at Kitt Peak National Observatory (KPNO). Taking advantage of the short-wavelength coverage, we are able to study the so-called ``big blue bump,'' the region where the energy output peaks, in detail. Most objects exhibit a spectral break around 1100 Angstrom Although this result is formally associated with large uncertainty for some objects, there is strong evidence in the data that the far-ultraviolet spectral region is below the extrapolation of the near-ultraviolet-optical slope, indicating a spectral break around 1100 Angstrom We compare the behavior of our sample to those of non-LTE thin-disk models covering a range in black-hole mass, Eddington ratio, disk inclination, and othe...

  13. Creep characterization of solder bumps using nanoindentation

    Science.gov (United States)

    Du, Yingjie; Liu, Xiao Hu; Fu, Boshen; Shaw, Thomas M.; Lu, Minhua; Wassick, Thomas A.; Bonilla, Griselda; Lu, Hongbing

    2017-08-01

    Current nanoindentation techniques for the measurement of creep properties are applicable to viscoplastic materials with negligible elastic deformations. A new technique for characterization of creep behavior is needed for situations where the elastic deformation plays a significant role. In this paper, the effect of elastic deformation on the determination of creep parameters using nanoindentation with a self-similar nanoindenter tip is evaluated using finite element analysis (FEA). It is found that the creep exponent measured from nanoindentation without taking into account of the contribution of elastic deformation tends to be higher than the actual value. An effective correction method is developed to consider the elastic deformation in the calculation of creep parameters. FEA shows that this method provides accurate creep exponent. The creep parameters, namely the creep exponent and activation energy, were measured for three types of reflowed solder bumps using the nanoindentation method. The measured parameters were verified using FEA. The results show that the new correction approach allows extraction of creep parameters with precision from nanoindentation data.

  14. Numerical analysis of bump foil bearings without nominal radial clearance

    Institute of Scientific and Technical Information of China (English)

    LIU Zhan-sheng; XU Huai-jin; ZHANG Guang-hui

    2008-01-01

    Bump foil bearings without nominal radial clearance were analyzed. An air film thickness model and a bearing theoretical analytical model were developed accounting for air compressibility and foil deformation. To analyze hydrodynamic characteristics of bump foil beatings with different operating eccentricities, the air film thickness equation and Reynolds equation were coupled through pressure and solved by Newton-Raphson Method(NRM) and Finite Difference Method (FDM). The characteristics of an bump foil bearing model were dis-cussed including load carrying capacity, film thickness and pressure distributions. The results of simulation show that bump foil beating without nominal radial clearance can provide better stability and greater load capaci-ty. This numerical analytical method also reveals a good convergence in numerical calculation.

  15. Low-cost bump bonding activities at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Vaehaenen, S; Tick, T; Campbell, M, E-mail: Sami.vaehaenen@cern.c [CERN, PH-ESE 1211 Geneva 23 (Switzerland)

    2010-11-15

    Conventional bumping processes used in the fabrication of hybrid pixel detectors for High Energy Physics (HEP) experiments use electroplating for Under Bump Metallization (UBM) and solder bump deposition. This process is laborious, involves time consuming photolithography and can only be performed using whole wafers. Electroplating has been found to be expensive when used for the low volumes which are typical of HEP experiments. In the low-cost bump bonding development work, electroless deposition technology of UBM is studied as an alternative to the electroplating process in the bump size / pitch window beginning from 20 {mu}m / 50 {mu}m. Electroless UBM deposition used in combination with solder transfer techniques has the potential to significantly lower the cost of wafer bumping without requiring increased wafer volumes. A test vehicle design of sensor and readout chip, having daisy chains and Kelvin bump structures, was created to characterize the flip chip process with electroless UBM. Two batches of test vehicle wafers were manufactured with different bump pad metallization. Batch no. 1 had AlSi(1%) metallization, which is similar to the one used on sensor wafers, and Batch no. 2 had AlSi(2%)Cu(1%) metallization, which is very similar to the one used on readout wafers. Electroless UBMs were deposited on both wafer batches. In addition, electroplated Ni UBM and SnPb solder bumps were grown on the test sensor wafers. Test assemblies were made by flip chip bonding the solder-bumped test sensors against the test readout chips with electroless UBMs. Electrical yields and individual joint resistances were measured from assemblies, and the results were compared to a well known reference technique based on electroplated solder bumps structures on both chips. The electroless UBMs deposited on AlSi(2%)Cu(1%) metallization showed excellent electrical yields and small tolerances in individual joint resistance. The results from the UBMs deposited on AlSi(1

  16. Do You Hear a Bump or a Hole?

    DEFF Research Database (Denmark)

    Serafin, Stefania; Turchet, Luca; Nordahl, Rolf

    2010-01-01

    In this paper, we present a preliminary experiment whose goal is to assess the role of temporal aspects in sonically simulating the act of walking on a bump or a hole. In particular, we investigate whether the timing between heel and toe and the timing between footsteps affects the perception of ...... of walking on unflat surfaces. Results show that it is possible to simulate a bump or a hole by only using temporal information in the auditory modality....

  17. Quality of scintillating fibres after hot bump shrinking

    CERN Document Server

    Rodrigues Cavalcante, Ana Barbara; Joram, Christian

    2016-01-01

    Shrinking the diameter of fibre bumps by a hot drawing tool requires to run the fibre through the hot tool over its full length, bearing the risk of a degradation of the fibre performance. In this study we demonstrated that the hot bump shrinking method has no visible effect on the optical attenuation length, the light yield following ionising radiation, the diameter, the mechanical stability and the integrity of the cladding. For the latter, even a small positive impact was observed.

  18. New Pulsed Orbit Bump Magnets for the Fermilab Booster Synchrotron

    CERN Document Server

    Lackey, James; John, Carson; Kashikhin, Vladimir; Makarov, Alexander; Prebys, Eric

    2005-01-01

    The beam from the Fermilab Linac is injected onto a bump in the closed orbit of the Booster Synchrotron where a carbon foil strips the electrons from the Linac’s negative ion hydrogen beam. Although the Booster itself runs at 15Hz, heat dissipation in the orbit bump magnets has been one limitation to the fraction of the cycles that can be used for beam. New, 0.28T pulsed window frame dipole magnets have been constructed that will fit into the same space as the old ones, run at the full repetition rate of the Booster, and provide a larger bump to allow a cleaner injection orbit. The new magnets use a high saturation flux density Ni-Zn ferrite in the yoke rather than laminated steel. The presented magnetic design includes two and three dimensional magnetic field calculations with eddy currents and ferrite nonlinear effects.

  19. Analysis of mechanism of shock bump due to roof fall

    Institute of Scientific and Technical Information of China (English)

    GU Xin-jian; LI Jian-xiong

    2004-01-01

    According to the characteristics of the shock bump due to roof fall, a simple mechanics model has been established by applying the catastrophic theory and the law of energy conservation. The author suggests that the shock bump may be induced by the sudden energy release in the roof falling after underground mineral extractions, and through the systematic analysis of actual examples on site, the empirical formulae for the roof falling and energy release are derived, which would provide a new way for the study of the origin and mechanism of mine tremor due to fallen-in roof structure. It is of a great importance to enrich the shock bump theory and production safety in mine.

  20. Directional Nanoslit-Bump Coupler for Surface Plasmon Polaritons

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong-Liang; ZHAO De-Yin; ZHOU Chuan-Hong; JIANG Xun-Ya

    2008-01-01

    We investigate a p-polarized plane wave transmitted through a metallic slit-bump nanostructure using the finite difference time domain simulation.It is found that narrow bumps with suitable separation can diffract surface plasmons into highly directional collimating beams,The number and directionality of the beams can be controlled by adjusting the geometry parameters of the nanostructure.The structure with optimized parameters may be interesting for practical applications as directional nanoslit SPP-light coupler in integrated photonic devices.

  1. Hanford Waste Tank Bump Accident and Consequence Analysis

    Energy Technology Data Exchange (ETDEWEB)

    BRATZEL, D.R.

    2000-06-20

    This report provides a new evaluation of the Hanford tank bump accident analysis and consequences for incorporation into the Authorization Basis. The analysis scope is for the safe storage of waste in its current configuration in single-shell and double-shell tanks.

  2. The first bump-bonded pixel detectors on CVD diamond

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Palmieri, V.G.; Pan, L.S.; Peitz, A.; Pernicka, M.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Steuerer, J.; Stone, R.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W. E-mail: william@physics.utoronto.ca; Turchetta, R.; Vittone, E.; Wagner, A.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Zeuner, W.; Ziock, H.; Zoeller, M.; Charles, E.; Ciocio, A.; Dao, K.; Einsweiler, K.; Fasching, D.; Gilchriese, M.; Joshi, A.; Kleinfelder, S.; Milgrome, O.; Palaio, N.; Richardson, J.; Sinervo, P.; Zizka, G

    1999-11-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98% of the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 {mu}m was observed, consistent with expectations given the detector pitch.

  3. Extended-spectrum antiprotozoal bumped kinase inhibitors: A review.

    Science.gov (United States)

    Van Voorhis, Wesley C; Doggett, J Stone; Parsons, Marilyn; Hulverson, Matthew A; Choi, Ryan; Arnold, Samuel L M; Riggs, Michael W; Hemphill, Andrew; Howe, Daniel K; Mealey, Robert H; Lau, Audrey O T; Merritt, Ethan A; Maly, Dustin J; Fan, Erkang; Ojo, Kayode K

    2017-09-01

    Many life-cycle processes in parasites are regulated by protein phosphorylation. Hence, disruption of essential protein kinase function has been explored for therapy of parasitic diseases. However, the difficulty of inhibiting parasite protein kinases to the exclusion of host orthologues poses a practical challenge. A possible path around this difficulty is the use of bumped kinase inhibitors for targeting calcium-dependent protein kinases that contain atypically small gatekeeper residues and are crucial for pathogenic apicomplexan parasites' survival and proliferation. In this article, we review efficacy against the kinase target, parasite growth in vitro, and in animal infection models, as well as the relevant pharmacokinetic and safety parameters of bumped kinase inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The 5 MeV bump - a nuclear whodunit mystery

    CERN Document Server

    Huber, Patrick

    2016-01-01

    We perform a combined analysis of recent NEOS and Daya Bay data on the reactor antineutrino spectrum. This analysis includes approximately 1.5 million antineutrino events, which is the largest neutrino event sample analyzed to date. We use a double ratio which cancels flux model dependence and related uncertainties as well as the effects of the detector response model. We find at 3-4 standard deviation significance level, that plutonium-239 and plutonium-241 are disfavored as the single source for the the so-called 5 MeV bump. This analysis method has general applicability and in particular with higher statistics data sets will be able to shed significant light on the issue of the bump. With some caveat this also should allow to improve the sensitivity for sterile neutrino searches in NEOS.

  5. The AGB bump: a calibrator for the core mixing

    CERN Document Server

    Bossini, Diego; Salaris, Maurizio; Girardi, Léo; Montalbán, Josefina; Bressan, Alessandro; Marigo, Paola; Noels, Arlette

    2015-01-01

    The efficiency of convection in stars affects many aspects of their evolution and remains one of the key-open questions in stellar modelling. In particular, the size of the mixed core in core-He-burning low-mass stars is still uncertain and impacts the lifetime of this evolutionary phase and, e.g., the C/O profile in white dwarfs. One of the known observables related to the Horizontal Branch (HB) and Asymptotic Giant Branch (AGB) evolution is the AGB bump. Its luminosity depends on the position in mass of the helium-burning shell at its first ignition, that is affected by the extension of the central mixed region. In this preliminary work we show how various assumptions on near-core mixing and on the thermal stratification in the overshooting region affect the luminosity of the AGB bump, as well as the period spacing of gravity modes in core-He-burning models.

  6. The AGB bump: a calibrator for core mixing

    Science.gov (United States)

    Bossini, Diego; Miglio, Andrea; Salaris, Maurizio; Girardi, Léo; Montalbán, Josefina; Bressan, Alessandro; Marigo, Paola; Noels, Arlette

    2015-09-01

    The efficiency of convection in stars affects many aspects of their evolution and remains one of the key-open questions in stellar modelling. In particular, the size of the mixed core in core-He-burning low-mass stars is still uncertain and impacts the lifetime of this evolutionary phase and, e.g., the C/O profile in white dwarfs. One of the known observables related to the Horizontal Branch (HB) and Asymptotic Giant Branch (AGB) evolution is the AGB bump. Its luminosity depends on the position in mass of the helium-burning shell at its first ignition, that is affected by the extension of the central mixed region. In this preliminary work we show how various assumptions on near-core mixing and on the thermal stratification in the overshooting region affect the luminosity of the AGB bump, as well as the period spacing of gravity modes in core-He-burning models.

  7. The AGB bump: a calibrator for core mixing

    Directory of Open Access Journals (Sweden)

    Bossini Diego

    2015-01-01

    Full Text Available The efficiency of convection in stars affects many aspects of their evolution and remains one of the key-open questions in stellar modelling. In particular, the size of the mixed core in core-He-burning low-mass stars is still uncertain and impacts the lifetime of this evolutionary phase and, e.g., the C/O profile in white dwarfs. One of the known observables related to the Horizontal Branch (HB and Asymptotic Giant Branch (AGB evolution is the AGB bump. Its luminosity depends on the position in mass of the helium-burning shell at its first ignition, that is affected by the extension of the central mixed region. In this preliminary work we show how various assumptions on near-core mixing and on the thermal stratification in the overshooting region affect the luminosity of the AGB bump, as well as the period spacing of gravity modes in core-He-burning models.

  8. Life story chapters, specific memories and the reminiscence bump

    DEFF Research Database (Denmark)

    Thomsen, Dorthe Kirkegaard; Pillemer, David B.; Ivcevic, Zorana

    2011-01-01

    Theories of autobiographical memory posit that extended time periods (here termed chapters) and memories are organised hierarchically. If chapters organise memories and guide their recall, then chapters and memories should show similar temporal distributions over the life course. Previous research...... demonstrates that positive but not negative memories show a reminiscence bump and that memories cluster at the beginning of extended time periods. The current study tested the hypotheses that (1) ages marking the beginning of positive but not negative chapters produce a bump, and that (2) specific memories...... are over-represented at the beginning of chapters. Potential connections between chapters and the cultural life script are also examined. Adult participants first divided their life story into chapters and identified their most positive and most negative chapter. They then recalled a specific memory from...

  9. Injection Bump Synchronization Study for the CERN PS

    CERN Document Server

    Serluca, Maurizio; Gilardoni, Simone; CERN. Geneva. ATS Department

    2016-01-01

    In the framework of the LHC Injector Upgrade (LIU) project the CERN PS injection kinetic energy will be upgraded from 1.4 to 2 GeV. The present injection bump is made by four bumpers in Straight Section (SS) 40, 42, 43, 44 and it will be converted in a five bumpers system to allow additional flexibility in the bump shape with a reduction of the proton losses during the bump closure. The injection section SS42 has being redesigned to accommodate a new eddy current septum which will host a new bumper magnet in the same vacuum vessel due to reduced longitudinal space availability. The synchronization and amplitude variation of the power converter of the in-vacuum bumper 42 with respect to the remaining outside vacuum bumpers 40, 41, 43, 44 can lead to orbit distortion and consequent losses during injection. In this note we present the experimental results from Machine Development (MD) studies along with simulations for the present system at 1.4 GeV to quantify the acceptable orbit distortion and the performance ...

  10. Electromigration of composite Sn-Ag-Cu solder bumps

    Science.gov (United States)

    Sharma, Ashutosh; Xu, Di Erick; Chow, Jasper; Mayer, Michael; Sohn, Heung-Rak; Jung, Jae Pil

    2015-11-01

    This study investigates the electromigration (EM) behavior of lead free Sn-Ag-Cu (SAC) solder alloys that were reinforced with different types of nanoparticles [Copper-coated carbon nanotubes (Cu/CNT), La2O3, Graphene, SiC, and ZrO2]. The composite solders were bumped on a Cu substrate at 220°C, and the resistance of the bumped solders was measured using a four wire setup. Current aging was carried out for 4 hours at a temperature of 160°C, and an increase in resistance was noted during this time. Of all the composite solders that were studied, La2O3 and SiC reinforced SAC solders exhibited the smallest resistances after current aging. However, the rate of change in the resistance at room temperature was lower for the SiC-reinforced SAC solder. The SAC and Graphene reinforced SAC solder bumps completely failed within 15 - 20 min of these tests. The SiC nanoparticles were reported to possibly entrap the SAC atoms better than other nanoparticles with a lower rate of EM. [Figure not available: see fulltext.

  11. The reminiscence bump in autobiographical memory and for public events: A comparison across different cueing methods.

    Science.gov (United States)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    The reminiscence bump has been found for both autobiographical memories and memories of public events. However, there have been few comparisons of the bump across each type of event. In the current study, therefore, we compared the bump for autobiographical memories versus the bump for memories of public events. We did so between-subjects, through two cueing methods administered within-subjects, the cue word method and the important memories method. For word-cued memories, we found a similar bump from ages 5 to 19 for both types of memories. However, the bump was more pronounced for autobiographical memories. For most important memories, we found a bump from ages 20 to 29 in autobiographical memory, but little discernible age pattern for public events. Rather, specific public events (e.g., the Fall of the Berlin Wall) dominated recall, producing a chronological distribution characterised by spikes in citations according to the years these events occurred. Follow-up analyses suggested that the bump in most important autobiographical memories was a function of the cultural life script. Our findings did not yield support for any of the dominant existing accounts of the bump as underlying the bump in word-cued memories.

  12. Aqueous-based thick photoresist removal for bumping applications

    Science.gov (United States)

    Moore, John C.; Brewer, Alex J.; Law, Alman; Pettit, Jared M.

    2015-03-01

    Cleaning processes account for over 25% of processing in microelectronic manufacturing [1], suggesting electronics to be one of the most chemical intensive markets in commerce. Industry roadmaps exist to reduce chemical exposure, usage, and waste [2]. Companies are encouraged to create a safer working environment, or green factory, and ultimately become certified similar to LEED in the building industry [3]. A significant step in this direction is the integration of aqueous-based photoresist (PR) strippers which eliminate regulatory risks and cut costs by over 50%. One of the largest organic solvent usages is based upon thick PR removal during bumping processes [4-6]. Using market projections and the benefits of recycling, it is estimated that over 1,000 metric tons (mt) of residuals originating from bumping processes are incinerated or sent to a landfill. Aqueous-based stripping would eliminate this disposal while also reducing the daily risks to workers and added permitting costs. Positive-tone PR dissolves in aqueous strippers while negative-tone systems are lifted-off from the substrate, bumps, pillars, and redistribution layers (RDL). While the wafers are further processed and rinsed, the lifted-off PR is pumped from the tank, collected onto a filter, and periodically back-flushed to the trash. The PR solids become a non-hazardous plastic waste while the liquids are mixed with the developer stream, neutralized, filtered, and in most cases, disposed to the sewer. Regardless of PR thickness, removal processes may be tuned to perform in <15min, performing at rates nearly 10X faster than solvents with higher bath lives. A balanced formula is safe for metals, dielectrics, and may be customized to any fab.

  13. Structure of Three-Dimensional Separated Flow on Symmetric Bumps

    Science.gov (United States)

    2005-11-30

    calculated using N - tan(SSA) -ni(/W/iy) t (1 N- - = - --(4 1 )tan(F(;A) - UII /(LI/’) where vih and 17’- are the stream-wise and span-wise eddy...velocity vectors only in bimodal region and the black lines are connecting these vectors for visual aid . As expected, the two flow patterns are totally... aid only at different yi of. Figure 5.7 Normalized FrF + IWk- vectors locally tangent to surface. 5. LDV Measurements near Large Bump#3 Surface 160

  14. Analysis of Power Generating Speed Bumps Made of Concrete Foam Composite

    Science.gov (United States)

    Syam, B.; Muttaqin, M.; Hastrino, D.; Sebayang, A.; Basuki, W. S.; Sabri, M.; Abda, S.

    2017-03-01

    This paper discusses the analysis of speed bump made of concrete foam composite which is used to generate electrical power. Speed bumps are designed to decelerate the speed of vehicles before passing through toll gates, public areas, or any other safety purposes. In Indonesia a speed bump should be designed in the accordance with KM Menhub 3 year 1994. In this research, the speed bump was manufactured with dimensions and geometry comply to the regulation mentioned above. Concrete foam composite speed bumps were used due to its light weight and relatively strong to receive vertical forces from the tyres of vehicles passing over the bumps. The reinforcement materials are processed from empty fruit bunch of oil palm. The materials were subjected to various tests to obtain its physical and mechanical properties. To analyze the structure stability of the speed bumps some models were analyzed using a FEM-based numerical softwares. It was obtained that the speed bumps coupled with polymeric composite bar (3 inches in diameter) are significantly reduce the radial stresses. In addition, the speed bumps equipped with polymeric composite casing or steel casing are also suitable for use as part of system components in producing electrical energy.

  15. The Effects of Campus Bump on Drivers’ Fixation Dispersion and Speed Reduction

    Directory of Open Access Journals (Sweden)

    Qian Xu

    2015-01-01

    Full Text Available To evaluate the effects of campus speed bumps on drivers’ speed and fixation distribution, a quasinaturalistic driving test was conducted on a Chinese campus. Seven randomly selected drivers, wearing the Dikablis eye tracking devices, were required to drive an OPEL SUV passing the speed bumps. The area close to the bump was divided into ten subsegments (15 m for each one. The degree of fixation dispersion within each subsegment was defined as the distance from each subcenter to the whole fixation center. All traffic data were recorded using mounted camera, and the trajectories were extracted in Matlab. The speed and trajectory data was divided into two groups: the before group for bump-free case and the after group for a 5 cm bump case. The observational before-after analysis shows statistical significance between the two cases. The individual vehicular speed analysis reveals that bump reduces nearly 60% of vehicles’ speeds to a certain extent within the distance from 30 m upstream to 15 m downstream. The drivers’ fixation points begin to disperse 30–45 m before they see the bump, and it falls back to normal level 15–30 m downstream of the bump. These findings will help engineers install speed bumps at the most appropriate locations.

  16. The peaks of life: The differential temporal locations of the reminiscence bump across disparate cueing methods

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    The reminiscence bump has generally been assessed through either (1) the cue word method, or (2) several related methods which we refer to under the umbrella of the important memories method. Here we provide a review of the literature demonstrating that the temporal location of the bump varies...... systematically according to cueing method, with the mean range of the bump located from 8.7 to 22.5 years of age for word-cued memories, versus 15.1 to 27.9 for important memories. This finding has hitherto been under-acknowledged, as existing theoretical accounts of the bump generally hold its location...

  17. Sensory feedback in a bump attractor model of path integration.

    Science.gov (United States)

    Poll, Daniel B; Nguyen, Khanh; Kilpatrick, Zachary P

    2016-04-01

    Mammalian spatial navigation systems utilize several different sensory information channels. This information is converted into a neural code that represents the animal's current position in space by engaging place cell, grid cell, and head direction cell networks. In particular, sensory landmark (allothetic) cues can be utilized in concert with an animal's knowledge of its own velocity (idiothetic) cues to generate a more accurate representation of position than path integration provides on its own (Battaglia et al. The Journal of Neuroscience 24(19):4541-4550 (2004)). We develop a computational model that merges path integration with feedback from external sensory cues that provide a reliable representation of spatial position along an annular track. Starting with a continuous bump attractor model, we explore the impact of synaptic spatial asymmetry and heterogeneity, which disrupt the position code of the path integration process. We use asymptotic analysis to reduce the bump attractor model to a single scalar equation whose potential represents the impact of asymmetry and heterogeneity. Such imperfections cause errors to build up when the network performs path integration, but these errors can be corrected by an external control signal representing the effects of sensory cues. We demonstrate that there is an optimal strength and decay rate of the control signal when cues appear either periodically or randomly. A similar analysis is performed when errors in path integration arise from dynamic noise fluctuations. Again, there is an optimal strength and decay of discrete control that minimizes the path integration error.

  18. The peaks of life: The differential temporal locations of the reminiscence bump across disparate cueing methods

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    The reminiscence bump has generally been assessed through either (1) the cue word method, or (2) several related methods which we refer to under the umbrella of the important memories method. Here we provide a review of the literature demonstrating that the temporal location of the bump varies sy...

  19. Experimental and modeling study of the flow over a skewed bump

    Science.gov (United States)

    Ching, David S.; Elkins, Christopher J.; Eaton, John K.

    2016-11-01

    Three-dimensional separated flows can be very sensitive to geometry and inlet conditions, such that a small change in the geometry or the upstream boundary layer could cause the flow structure to change drastically. This study examines the geometric sensitivity of a skewed bump with axis ratio 4/3 by changing the angle of the bump with respect to the flow. The three-dimensional, three-component mean velocity field was acquired using Magnetic Resonance Velocimetry (MRV) for several bump angles. The flow is dominated by large coherent vortices in the wake. For a symmetric case, two counter-rotating vortices exist in the wake, but when the bump is skewed relative to the oncoming flow one vortex structure is much stronger and overwhelms the other vortex. A comparison to RANS simulations found that the RANS simulations predict the velocity fields with reasonable accuracy within the separation bubble, but are very inaccurate downstream of reattachment. Using a time-resolved MRV sequence, the shedding frequency of the wake was determined for two bump angles. Hot-wire anemometry confirmed the shedding frequencies found from the MRV data and observed that the shedding frequency is sensitive to the bump angle at low bump angles, but is insensitive at high bump angles. Funding provided by the Office of Naval Research.

  20. Development of a solder bump technique for contacting a three-dimensional multi electrode array

    NARCIS (Netherlands)

    Frieswijk, T.A.; Frieswijk, T.A.; Bielen, J.A.; Bielen, J.A.; Rutten, Wim; Bergveld, Piet

    1997-01-01

    The application of a solder bump technique for contacting a three-dimensional multi electrode array is presented. Solder bumping (or C4: Controlled Collapse Chip Connections, also called Flip Chip contacting) is the most suitable contacting technique available for small dimensions and large numbers

  1. Shrinking of bumps by drawing scintillating fibres through a hot conical tool

    CERN Document Server

    Rodrigues Cavalcante, Ana Barbara; Gavardi, Laura; Joram, Christian; Kristic, Robert; Pierschel, Gerhard; Schneider, Thomas

    2016-01-01

    The LHCb SciFi tracker will be based on scintillating fibres with a nominal diameter of 250 $\\mu$m. A small length fraction of these fibres shows millimetre-scale fluctuations of the diameter, also known as bumps and necks. In particular, bumps exceeding a diameter of about 350 $\\mu$m are problematic as they can distort the winding pattern of the fibre mats over more extended regions. We present a method to reduce the diameter of large bumps to a diameter of 350 $\\mu$m by locally heating and pulling the fibre through a conical tool. The method has been proven to work for bumps up to 450 – 500 $\\mu$m diameter. Larger bumps need to be treated manually by a cut-and-glue technique which relies on UV-curing instant glue. The bump shrinking and cut-and-glue processes were integrated in a fibre diameter scanner at CERN. The central scanning and bump shrinking of all fibres is expected to minimise bump related issues at the four mat winding centres of the SciFi project.

  2. 2D-bail simulations on stiffness influences for coal bump

    Institute of Scientific and Technical Information of China (English)

    TAN Yun-liang; SUN Chun-jiang; ZHANG Zhen-yu

    2009-01-01

    Coal bump is a dynamic process, thus it is necessary to reveal the process validly. 2D-ball code is an efficient approach developed by the authors based on the basic DEM rationale proposed by Cundall. Numerical simulations show that the coal bump ex-periences a process of energy accumulation, sudden release of energy and energy de-crease. The stiffness of coal particles has a great influence on the coal bump morphosis and particle velocity. Generally, the larger the stiffness of particles, the longer the shooting off period and the larger the bump velocity. This is in agreement with the results of labora-tory experiment and in-situ studies. However, the stiffness of particles has an influence on the quantity value energy and no influence on the releasing energy pattern of the coal bump.

  3. Seismic Hazard Prediction Using Seismic Bumps: A Data Mining Approach

    Directory of Open Access Journals (Sweden)

    Musa Peker

    2016-04-01

    Full Text Available Due to the large number of influencing factors, it is difficult to predict the earthquake which is a natural disaster. Researchers are working intensively on earthquake prediction. Loss of life and property can be minimized with earthquake prediction. In this study, a system is proposed for earthquake prediction with data mining techniques. In the study in which Cross Industry Standard Process for Data Mining (CRISP-DM approach has been used as data mining methodology, seismic bumps data obtained from mines has been analyzed. Extreme learning machine (ELM which is an effective and rapid classification algorithm has been used in the modeling phase. In the evaluation stage, different performance evaluation criteria such as classification accuracy, sensitivity, specificity and kappa value have been used. The results are promising for earthquake prediction.

  4. A Bump in the Blue Axion Isocurvature Spectrum

    CERN Document Server

    Chung, Daniel J H

    2016-01-01

    Blue axion isocurvature perturbations are both theoretically well-motivated and interesting from a detectability perspective. These power spectra generically have a break from the blue region to a flat region. Previous investigations of the power spectra were analytic, which left a gap in the predicted spectrum in the break region due to the non-applicability of the used analytic techniques. We therefore compute the isocurvature spectrum numerically for an explicit supersymmetric axion model. We find a bump that enhances the isocurvature signal for this class of scenarios. A fitting function of three parameters is constructed that fits the spectrum well for the particular axion model we study. This fitting function should be useful for blue isocurvature signal hunting in data and making experimental sensitivity forecasts.

  5. Investigation of fuel behaviour at different power levels (SKI-bump II). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lysell, G.; Bengtsson, Sven

    1994-12-31

    Fuel microstructure and fission product redistribution in the fuel and to the cladding inside were studied after a `bump` irradiation of a high burnup rod up to maximum Linear Heat Rating (LHR) of 43 kW/m. Fission gas induced swelling of the fuel imposed a large strain on the cladding. Total gas release in the rod as well as the local release at two different LHRs were measured. Reference fuel not subject to the bump was examined with the same techniques as the bumped fuel.

  6. Apparatus for Precise Indium-Bump Bonding of Microchips

    Science.gov (United States)

    Wild, Larry; Mulder, Jerry; Alvarado, Nicholas

    2005-01-01

    An improved apparatus has been designed and built for use in precise positioning and pressing of a microchip onto a substrate (which could, optionally, be another microchip) for the purpose of indium-bump bonding. The apparatus (see figure) includes the following: A stereomicroscope, A stage for precise positioning of the microchip in rotation angle (theta) about the nominally vertical pressing axis and in translation along two nominally horizontal coordinate axes (x and y), and An actuator system that causes a bonding tip to press the microchip against the substrate with a precisely controlled force. In operation, the microscope and the stage are used to position the microchip under the bonding tip and to align the indium bumps on the chip and the substrate, then the actuator system is used to apply a prescribed bonding force for a prescribed time. The improved apparatus supplants a partly similar prior apparatus that operated with less precision and repeatability, producing inconsistent and unreliable bonds. Results of the use of the prior apparatus included broken microchips, uneven bonds, and bonds characterized, variously, by overcompression or undercompression. In that apparatus, the bonding force was generated and controlled by use of a micrometer head positioned over the center of a spring-loaded scale, and the force was applied to the microchip via the scale, which was equipped for digital readout of the force. The inconsistency of results was attributed to the following causes: It was not possible to control the bonding force with sufficient precision or repeatability. Particularly troublesome was the inability to control the force at levels less than the weight of 150 g. Excessive compliance in the spring-loaded scale, combined with deviations from parallelarity of the substrate and bonding-tip surfaces, gave rise to nonuniformity in the pressure applied to the microchip, thereby generating excessive stresses and deformations in the microchip. In the

  7. Franz Joseph Gall and music: the faculty and the bump.

    Science.gov (United States)

    Eling, Paul; Finger, Stanley; Whitaker, Harry

    2015-01-01

    The traditional story maintains that Franz Joseph Gall's (1758-1828) scientific program began with his observations of schoolmates with bulging eyes and good verbal memories. But his search to understand human nature, in particular individual differences in capacities, passions, and tendencies, can also be traced to other important observations, one being of a young girl with an exceptional talent for music. Rejecting contemporary notions of cognition, Gall concluded that behavior results from the interaction of a limited set of basic faculties, each with its own processes for perception and memory, each with its own territory in both cerebral or cerebellar cortices. Gall identified 27 faculties, one being the sense of tone relations or music. The description of the latter is identical in both his Anatomie et Physiologie and Sur les Fonctions du Cerveau et sur Celles de Chacune de ses Parties, where he provided positive and negative evidences and discussed findings from humans and lower animals, for the faculty. The localization of the cortical faculty for talented musicians, he explained, is demonstrated by a "bump" on each side of the skull just above the angle of the eye; hence, the lower forehead of musicians is broader or squarer than in other individuals. Additionally, differences between singing and nonsinging birds also correlate with cranial features. Gall even brought age, racial, and national differences into the picture. What he wrote about music reveals much about his science and creative thinking.

  8. Bump hunting in LHC t t ¯ events

    Science.gov (United States)

    Czakon, Michal; Heymes, David; Mitov, Alexander

    2016-12-01

    We demonstrate that a purposefully normalized next-to-next-to-leading-order mt t ¯ differential spectrum can have very small theoretical uncertainty and, in particular, a small sensitivity to the top quark mass. Such an observable can thus be a very effective bump-hunting tool for resonances decaying to t t ¯ events during LHC run II and beyond. To illustrate how the approach works, we concentrate on one specific example of current interest, namely, the possible 750 GeV digamma excess resonance Φ . Considering only theoretical uncertainties, we demonstrate that it is possible to distinguish p p →Φ →t t ¯ signals studied in the recent literature [Hespel, Maltoni, and Vryonidou, J. High Energy Phys. 10 (2016) 016, 10.1007/JHEP10(2016)016] from the pure Standard Model background with very high significance. Alternatively, in the case of nonobservation, a strong upper limit on the decay rate Φ →t t ¯ can be placed.

  9. Ship Sensor Observations for Investigating the Charleston Bump 2003 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly measurements made by selected ship sensors on the R/V Seward Johnson during the "Investigating the Charleston Bump 2003" expedition sponsored by the National...

  10. Comparison of Off-Line IR Bump and Action-Angle Kick Minimization

    CERN Document Server

    Luo, Yun; Ptitsyn, Vadim; Trbojevic, Dejan; Wei, Jie

    2005-01-01

    The interaction region bump (IR bump) nonlinear correction method has been used for the sextupole and octupole field error on-line corrections in the Relativistic Heavy Ion Collider (RHIC). Some differences were found for the sextupole and octupole corrector strengths between the on-line IR bump correction and the predictions from the action-angle kick minimization. In this report we compare the corrector strengths from these two methods based on the RHIC Blue ring lattice with the IR nonlinear modeling. The comparison confirms the differences between resulting corrector strengths. And the reason for the differences is found and discussed. It is followed by a further discussion of the operational IR bump applications to the octupole, and skew sextupole and skew quadrupole field error corrections.

  11. Submersible Data (Dive Trackpoints) for Investigating the Charleston Bump 2003 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II along its track during fourteen dives of the 2003 "Investigating the Charleston Bump"...

  12. Two-Dimensional Bumps in Piecewise Smooth Neural Fields with Synaptic Depression

    KAUST Repository

    Bressloff, Paul C.

    2011-01-01

    We analyze radially symmetric bumps in a two-dimensional piecewise-smooth neural field model with synaptic depression. The continuum dynamics is described in terms of a nonlocal integrodifferential equation, in which the integral kernel represents the spatial distribution of synaptic weights between populations of neurons whose mean firing rate is taken to be a Heaviside function of local activity. Synaptic depression dynamically reduces the strength of synaptic weights in response to increases in activity. We show that in the case of a Mexican hat weight distribution, sufficiently strong synaptic depression can destabilize a stationary bump solution that would be stable in the absence of depression. Numerically it is found that the resulting instability leads to the formation of a traveling spot. The local stability of a bump is determined by solutions to a system of pseudolinear equations that take into account the sign of perturbations around the circular bump boundary. © 2011 Society for Industrial and Applied Mathematics.

  13. Indium bump array fabrication on small CMOS circuit for flip-chip bonding

    Institute of Scientific and Technical Information of China (English)

    Huang Yuyang; Zhang Yuxiang; Yin Zhizhen; Cui Guoxin; Liu H C; Bian Lifeng; Yang Hui; Zhang Yaohui

    2011-01-01

    We demonstrate a novel method for indium bump fabrication on a small CMOS circuit chip that is to be flip-chip bonded with a GaAs/AlGaAs multiple quantum well spatial light modulator.A chip holder with a via hole is used to coat the photoresist for indium bump lift-off.The 1000 μm-wide photoresist edge bead around the circuit chip can be reduced to less than 500μm,which ensures the integrity of the indium bump array.64 × 64 indium arrays with 20 μm-high,30 μm-diameter bumps are successfully formed on a 5 × 6.5 mm2 CMOS chip.

  14. On some results of Bump-Choie and Choie-Kim

    CERN Document Server

    Hundley, Joseph

    2011-01-01

    This paper is motivated by a 2001 paper of Choie and Kim and a 2006 paper of Bump and Choie. The paper of Choie and Kim extends an earlier result of Bol for elliptic modular forms to the setting of Siegel and Jacobi forms. The paper of Bump and Choie provides a representation theoretic interpretation of the phenomenon, and shows how a natural generalization of Choie and Kim's result on Siegel modular forms follows from a natural conjecture regarding (g,K)-modules. In this paper, it is shown that the conjecture of Bump and Choie follows from work of Boe. A second proof which is along the lines of the proof given by Bump and Choie in the genus 2 case is also included, as is a similar treatment of the result of Choie and Kim on Jacobi forms.

  15. Fine-pitch wafer bumping and assembly for high density detector systems

    CERN Document Server

    Huffman, A; La Bennett, R; Statler, C

    2004-01-01

    A number of high energy physics experiments will rely on pixilated detector arrays to track particles generated in a collision event. In addition, several medical imaging applications are using pixilated devices as the imaging elements. The pixels in these detectors are very small (50-100 mu m pitch) to provide adequate spatial resolution for particle tracking. Since the pixels and their electrical interconnections are arrayed over the entire area of the device, solder bumping is the natural choice for the integration of detector elements to readout and support electronics. The small pitch of the I /O presents new challenges to the bumping and assembly processes. The processes for fabricating bumps and assembling the detectors must have a high yield and be compatible with a high radiation, high vacuum, and low temperature operating environment to provide the necessary performance and operating lifetime. This paper presents an overview of MCNC Research & Development Institute's bumping and assembly process...

  16. Optimization of Kicker Pulse Bump by Using a SR Monitor at the Photon Factory

    CERN Document Server

    Mitsuhashi, Toshiyuki

    2005-01-01

    We plan to operate the Photon Factory storage ring by top-up injection mode from 2006. To realize this operation mode, remaining coherent oscillation of the stored beam due to error in the injection pulse bump is one of most serious problem. To reducing the error in the injection pulse bump, we calibrated kicking angles of the injection kicker magnets by means of the term by term instantaneous observation of beam profile. We have a SR monitor inside of injection pulse bump. By measureing the tern by tern beam position after the excitation of kicker magnet, we can calibrate the kick angle of the kicker magnet. By using this calibration, we optimized injection pulse bump. As a result, we reduced amplitude of remaining coherent oscillation less than 1/4 of the 1??of the beam size.

  17. Multi-bump solutions in a neural field model with external inputs

    Science.gov (United States)

    Ferreira, Flora; Erlhagen, Wolfram; Bicho, Estela

    2016-07-01

    We study the conditions for the formation of multiple regions of high activity or "bumps" in a one-dimensional, homogeneous neural field with localized inputs. Stable multi-bump solutions of the integro-differential equation have been proposed as a model of a neural population representation of remembered external stimuli. We apply a class of oscillatory coupling functions and first derive criteria to the input width and distance, which relate to the synaptic couplings that guarantee the existence and stability of one and two regions of high activity. These input-induced patterns are attracted by the corresponding stable one-bump and two-bump solutions when the input is removed. We then extend our analytical and numerical investigation to N-bump solutions showing that the constraints on the input shape derived for the two-bump case can be exploited to generate a memory of N > 2 localized inputs. We discuss the pattern formation process when either the conditions on the input shape are violated or when the spatial ranges of the excitatory and inhibitory connections are changed. An important aspect for applications is that the theoretical findings allow us to determine for a given coupling function the maximum number of localized inputs that can be stored in a given finite interval.

  18. Stability of bumps in piecewise smooth neural fields with nonlinear adaptation

    KAUST Repository

    Kilpatrick, Zachary P.

    2010-06-01

    We study the linear stability of stationary bumps in piecewise smooth neural fields with local negative feedback in the form of synaptic depression or spike frequency adaptation. The continuum dynamics is described in terms of a nonlocal integrodifferential equation, in which the integral kernel represents the spatial distribution of synaptic weights between populations of neurons whose mean firing rate is taken to be a Heaviside function of local activity. Discontinuities in the adaptation variable associated with a bump solution means that bump stability cannot be analyzed by constructing the Evans function for a network with a sigmoidal gain function and then taking the high-gain limit. In the case of synaptic depression, we show that linear stability can be formulated in terms of solutions to a system of pseudo-linear equations. We thus establish that sufficiently strong synaptic depression can destabilize a bump that is stable in the absence of depression. These instabilities are dominated by shift perturbations that evolve into traveling pulses. In the case of spike frequency adaptation, we show that for a wide class of perturbations the activity and adaptation variables decouple in the linear regime, thus allowing us to explicitly determine stability in terms of the spectrum of a smooth linear operator. We find that bumps are always unstable with respect to this class of perturbations, and destabilization of a bump can result in either a traveling pulse or a spatially localized breather. © 2010 Elsevier B.V. All rights reserved.

  19. Stress investigation on the rolling tires across the speed bump using finite element method

    Science.gov (United States)

    Hidayat, Royan; Pranoto, Sarwo Edy; Tauviqirrahman, Mohammad; Bayuseno, Athanasius P.

    2016-04-01

    The interaction between road surface and tire on a vehicle may strongly determine the vehicle's stability. This study was conducted to find out the stress distribution as a result of pressure on the tires rolling across the speed bumps. This study used Abaqus software to simulate the movement of the tire, which rolls across the speed bump to determine the stress distribution that may occur. The tire component material used was a full path rubber on a speed bump. For the boundary conditions of the study, it was assumed that the tires had load variations as much as 2 kN, 6 kN, 10 kN, as well as pressure variations as much as 17 Psi, 30 Psi, 40 Psi. The tires were then rolled 8 km/h crossing the speed bump. Modeling speed bumps also varied i.e. the first variation of speed bumps that have a height of 50 mm with a width of 250 mm, the second variation of height 75 mm with a width of 300 mm, and a third variation of height 100 mm with a width of 400 mm. The simulation was done by giving the tire pressures as much as 17 Psi, 30 Psi, 40 Psi and loads as much as 2 kN, 6 kN, 10 kN. Further, the tires were rolled three times. It was rolled crossing the first speed bump, the second, and the third, respectively. Results showed stress distribution's fig and graphs. From the analysis results and simulation, it was shown that the greater the load received by the tires, the higher stress they produced.

  20. Dynamic failure in coal seams:Implications of coal composition for bump susceptibility

    Institute of Scientific and Technical Information of China (English)

    Lawson Heather; Weakley Andrew; Miller Arthur

    2016-01-01

    As a contributing factor in the dynamic failure (bumping) of coal pillars, a bump-prone coal seam has been described as one that is ‘uncleated or poorly cleated, strong. . .that sustains high stresses.”Despite extensive research regarding engineering controls to help reduce the risk for coal bumps, there is a paucity of research related to the properties of coal itself and how those properties might contribute to the mechanics of failures. Geographic distribution of reportable dynamic failure events reveals a highly localized clustering of incidents despite widespread mining activities. This suggests that unique, contributing geologic characteristics exist within these regions that are less prevalent elsewhere. To investigate a new approach for identifying coal characteristics that might lead to bumping, a principal component analysis (PCA) was performed on 306 coal records from the Pennsylvania State Coal Sample database to determine which characteristics were most closely linked with a positive history of reportable bumping. Selected material properties from the data records for coal samples were chosen as variables for the PCA and included petrographic, elemental, and molecular properties. Results of the PCA suggest a clear correlation between low organic sulfur content and the occurrence of dynamic failure, and a secondary correlation between volatile matter and dynamic failure phenomena. The ratio of vola-tile matter to sulfur in the samples shows strong correlation with bump-prone regions, with a minimum threshold value of approximately 20, while correlations determined for other petrographic and elemental variables were more ambiguous. Results suggest that the composition of the coal itself is directly linked to how likely a coal is to have experienced a reportable dynamic failure event. These compositional controls are distinct from other previously established engineering and geologic criteria and represent a missing piece to the bump prediction puzzle.

  1. Application of robust color composite fringe in flip-chip solder bump 3-D measurement

    Science.gov (United States)

    Kuo, Chung-Feng Jeffrey; Wu, Han-Cheng

    2017-04-01

    This study developed a 3-D measurement system based on flip-chip solder bump, used fringes with different modulation intensities in color channels, in order to produce color composite fringe with robustness, and proposed a multi-channel composite phase unwrapping algorithm, which uses fringe modulation weights of different channels to recombine the phase information for better measurement accuracy and stability. The experimental results showed that the average measurement accuracy is 0.43μm and the standard deviation is 1.38 μm. The results thus proved that the proposed 3-D measurement system is effective in measuring a plane with a height of 50 μm. In the flip-chip solder bump measuring experiment, different fringe modulation configurations were tested to overcome the problem of reflective coefficient between the flip-chip base board and the solder bump. The proposed system has a good measurement results and robust stability in the solder bump measurement, and can be used for the measurement of 3-D information for micron flip-chip solder bump application.

  2. Investigation of Sn-Pb solder bumps of prototype photo detectors for the LHCb experiment

    CERN Document Server

    Delsante, M L; Arnau-Izquierdo, G

    2004-01-01

    The Large Hadron Collider (LHC) is now under construction at the European Organization for Nuclear Research (CERN). LHCb is one of the dedicated LHC experiments, allowing high energy proton-proton collisions to be exploited. This paper presents the results of the metallurgic studies carried out on Sn-Pb solder bumps of prototype vacuum photo detectors under development for LHCb, and in particular for the ring imaging Cherenkov-hybrid photo diode (RICH-HPD) project. These detectors encapsulate, in a vacuum tube, an assembly made of two silicon chips bonded together by a matrix of solder bumps. Each bump lies on a suitable system of under-bump metallic layers ensuring mechanical and electrical transition between the chip pad and the solder alloy. During manufacturing of the detector, bump-bonded (BB) assemblies are exposed to severe heat cycles up to 400 degree C inducing, in the present fabrication process, a clear degradation of electrical connectivity. Several investigations such as microstructural observati...

  3. The Best Location for Speed Bump Installation Using Experimental Design Methodology

    Directory of Open Access Journals (Sweden)

    Alireza Khademi

    2013-12-01

    Full Text Available Speed bumps, as traffic calming devices, have been extensively used to reduce traffic speed on local streets. This study represents a unique application of experimental design methodology where the effects of some controllable factors in determining the best location for installing speed bumps before stop points (e.g. entry gates, road junctions were investigated. Through Classical Design of Experiments (DOE, the optimum location of the speed bump was obtained based on the graphical plots of the significant effects. The speed at the stop point was treated as the response and minimum speed is desirable. Design-Expert® software was used to evaluate and analyze the results obtained. The suggested mathematical model effectively explains the performance indicators within the ranges of the factors. The car speed is the most significant factor that affects the distance-time in comparison with other factors, which provides secondary contributions.

  4. ADHESIVE CONTACT PROBLEM OF AXISYMMETRIC MINIATURE CIRCULAR PLATES WITH CENTRAL RIGID BUMP

    Institute of Scientific and Technical Information of China (English)

    Fu Yiming; Li Sheng; Tian Yanping

    2006-01-01

    Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.

  5. Load Express Analysis of the Car Running Against the Bumps in the Road

    Directory of Open Access Journals (Sweden)

    Yu. N. Baryshnikov

    2014-01-01

    Full Text Available In many fields of technology when calculating the strength there are options available to choose design cases and loads in compliance with different operating conditions. In the automotive industry there are no such standards yet. This is due to both a variety of operating conditions, and a complexity of calculating the actual loads.K. Ert`s article is considered to be a pioneering work in this regard. There the author makes a hypothesis of the linear dependence of torque acting on the car, and of the height of bumps in the road. All formulas were obtained for vehicles with the leaf spring suspensions. An appearing entire class of new cars made it necessary to generalize the experience.This paper proposes an engineering method for calculating the vertical loads acting on the car when bumping in the road. We derive general formulas to calculate the height of the road bumps (irregularities on the way of a running car with various types of suspension. A dump truck BELAZ with various types nonlinear of suspension has been used to test the obtained formulas. The results analysis has shown that under equal conditions a car with dependent rear suspension will bear the lower loads than its prototype with a different type of suspension.The paper presents the relationships between the hights of bumps, which cause an equivalent load when different wheels bump against them. It shows a relation between the loads acting on the car when bumping against the same road irregularity by different wheels. The practical significance of the equations is the possibility to calculate loads in various cases in the road using the one-test results. A comparative results analysis of analytical calculation of loads and numerical experiments is based on the nonlinear model of the vehicle.The proposed method is an effective tool for the rapid analysis of loads in the design and fine-tuning the car.

  6. Density bump formation in a collisionless electrostatic shock wave in a laser-ablated plasma

    CERN Document Server

    Garasev, M A; Kocharovsky, V V; Malkov, Yu A; Murzanev, A A; Nechaev, A A; Stepanov, A N

    2016-01-01

    The emergence of a density bump at the front of a collisionless electrostatic shock wave have been observed experimentally during the ablation of an aluminium foil by a femtosecond laser pulse. We have performed numerical simulations of the dynamics of this phenomena developing alongside the generation of a package of ion-acoustic waves, exposed to a continual flow of energetic electrons, in a collisionless plasma. We present the physical interpretation of the observed effects and show that the bump consists of transit particles, namely, the accelerated ions from the dense plasma layer, and the ions from the diluted background plasma, formed by a nanosecond laser prepulse during the ablation.

  7. Design of a local bump feedback system for a variably polarizing undulator.

    Science.gov (United States)

    Bizen, T; Shimada, T; Takao, M; Hiramatu, Y; Miyahara, Y

    1998-05-01

    A local bump feedback system is under construction to correct the orbit distortion caused by the magnetic field errors of a double-array undulator used to generate linear and circular polarization of light for a soft X-ray beamline. The local bump orbit is created by steering coils several turns long and four sets of steering magnets. The kick angle of the long steering coils and the steering magnets is determined according to the motion of the undulator and by detecting the beam position.

  8. The instability mechanics of surrounding rock-coal mass system in longwall face and the prevention of pressure bumps

    Institute of Scientific and Technical Information of China (English)

    李新元; 李英明

    2003-01-01

    According to the movement and change rules of mechanical structure of surrounding rock-coal mass system during coal excavation, the mechanism of sudden instability and damage was found out. The criterions that distinguishing the occurring of the pressure bump were put forward. This criteria have been applied successfully in the comprehensive prevent of pressure bumps in Tangshan colliery.

  9. The reminiscence bump for public events: A review of its prevalence and taxonomy of alternative age distributions

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark

    2013-01-01

    a legitimate effect, and (ii) the alternative age distributions that are otherwise seen in recall for public events. I conclude that, though the bump is frequently found, the legitimacy of the effect is contingent upon the strictness of the standard one employs. I also find significant exceptions to the bump...

  10. CO2laser-induced bump formation and growth on polystyrene for multi-depth soft lithography molds

    KAUST Repository

    Li, Huawei

    2012-10-19

    This paper reports the process of creating bumps on the surface of polystyrene (PS) induced by a CO2laser at low powers. The paper also outlines the procedure for growing bumps induced by multiple laser scans on the aforementioned bumps. These bumps result from the net volume gain of the laser heat-affected zone on the PS rather than from a deposition process, and the expansion of the heat-affected zone on PS was verified by measuring the hardness change using nanoindentation. The bumps have a much smoother surface than microchannels fabricated with laser cutting; depending on the laser power, they have heights ranging from hundreds of nanometers to 42m. The laser scanning speed and scan times along with this technique offer a fast and low-cost alternative for fabricating molds for multi-depth PDMS microfluidic devices. © 2012 IOP Publishing Ltd.

  11. Lateral Scanning Linnik Interferometry for Large Field of View and Fast Scanning: Wafer Bump Inspection

    Science.gov (United States)

    Kim, Min Y.; Veluvolu, Kalyana C.; Lee, Soon-Geul

    2011-07-01

    Wafer-level packaging is currently the major trend in semiconductor packaging for miniaturization and high-density integration. To ensure the package reliability, the wafer and substrate bumps utilized as connection junctions need to be in-line inspected as regards their top-height distribution, coplanarity, and volume uniformity. This article proposes a lateral scanning interferometric system for wafer bump shape inspection in three dimensions with a large field of view and fast inspection speed based on an optomechatronic system design. For multiple-peak interferogram from wafer bumps around a transparent film layer, two-step information extraction algorithms are suggested, including top surface profile and under-layer surface profile detection algorithms. The multiple-peak interferogram is acquired with variations of lateral position of the reference mirror by a piezoelectric transducer (PZT). A series of experiments is performed for representative wafer samples with solder and gold bumps, and the effectiveness of the proposed inspection system is verified from the test results.

  12. \\title{Low-Cost Bump-Bonding Processes for High Energy Physics Pixel Detectors}

    CERN Document Server

    Caselle, Michele; Colombo, Fabio; Dierlamm, Alexander Hermann; Husemann, Ulrich; Kudella, Simon; Weber, M

    2015-01-01

    In the next generation of collider experiments detectors will be challenged by unprecedented particle fluxes. Thus large detector arrays of highly pixelated detectors with minimal dead area at reasonable costs are required. Bump-bonding of pixel detectors has been shown to be a major cost-driver. KIT is one of the production centers of the CMS barrel pixel detector for the Phase I Upgrade. In this contribution the SnPb bump-bonding process and the production yield is reported. In parallel to the production of the new CMS pixel detector, several alternatives to the expensive photolithography electroplating/electroless metal deposition technologies are developing. Recent progress and challenges faced in the development of bump-bonding technology based on gold-stud bonding by thin ($15\\,\\rm{\\mu m}$) gold wire is presented. This technique allows producing metal bumps with diameters down to $30\\,\\rm{\\mu m}$ without using photolithography processes, which are typically required to provide suitable under bu...

  13. Decomposing the sales promotion bump accounting for cross-category effects

    NARCIS (Netherlands)

    Leeflang, Peter S. H.; Selva, Josefa Parreno; Wittink, Dick R.; Dijk, Albertus Alard van

    2008-01-01

    Extant research on the decomposition of unit sales bumps due to price promotions considers these effects only within a single product category. This article introduces a framework that accommodates specific cross-category effects. Empirical results based on daily data measured at the item/SKU level

  14. Photogrammetric 3d Acquisition and Analysis of Medicamentous Induced Pilomotor Reflex ("goose Bumps")

    Science.gov (United States)

    Schneider, D.; Hecht, A.

    2016-06-01

    In a current study at the University Hospital Dresden, Department of Neurology, the autonomous function of nerve fibres of the human skin is investigated. For this purpose, a specific medicament is applied on a small area of the skin of a test person which results in a local reaction (goose bumps). Based on the extent of the area, where the stimulation of the nerve fibres is visible, it can be concluded how the nerve function of the skin works. The aim of the investigation described in the paper is to generate 3D data of these goose bumps. Therefore, the paper analyses and compares different photogrammetric surface measurement techniques in regard to their suitability for the 3D acquisition of silicone imprints of the human skin. Furthermore, an appropriate processing procedure for analysing the recorded point cloud data is developed and presented. It was experimentally proven that by using (low-cost) photogrammetric techniques medicamentous induced goose bumps can be acquired in three dimensions and can be analysed almost fully automatically from the perspective of medical research questions. The relative accuracy was determined with 1% (RMSE) of the area resp. the volume of an individual goose bump.

  15. The 1600 Å Emission Bump in Protoplanetary Disks: A Spectral Signature of H2O Dissociation

    Science.gov (United States)

    France, Kevin; Roueff, Evelyne; Abgrall, Hervé

    2017-08-01

    The FUV continuum spectrum of many accreting pre-main sequence stars, Classical T Tauri Stars (CTTSs), does not continue smoothly from the well-studied Balmer continuum emission in the NUV, suggesting that additional processes contribute to the short-wavelength emission in these objects. The most notable spectral feature in the FUV continuum of some CTTSs is a broad emission approximately centered at 1600 Å, which has been referred to as the “1600 Å Bump.” The origin of this feature remains unclear. In an effort to better understand the molecular properties of planet-forming disks and the UV spectral properties of accreting protostars, we have assembled archival FUV spectra of 37 disk-hosting systems observed by the Hubble Space Telescope-Cosmic Origins Spectrograph. Clear 1600 Å Bump emission is observed above the smooth, underlying 1100-1800 Å continuum spectrum in 19/37 Classical T Tauri disks in the HST-COS sample, with the detection rate in transition disks (8/8) being much higher than that in primordial or non-transition sources (11/29). We describe a spectral deconvolution analysis to separate the Bump (spanning 1490-1690 Å) from the underlying FUV continuum, finding an average Bump luminosity L(Bump) ≈ 7 × 1029 erg s-1. Parameterizing the Bump with a combination of Gaussian and polynomial components, we find that the 1600 Å Bump is characterized by a peak wavelength λ o = 1598.6 ± 3.3 Å, with FWHM = 35.8 ± 19.1 Å. Contrary to previous studies, we find that this feature is inconsistent with models of H2 excited by electron -impact. We show that this Bump makes up between 5%-50% of the total FUV continuum emission in the 1490-1690 Å band and emits roughly 10%-80% of the total fluorescent H2 luminosity for stars with well-defined Bump features. Energetically, this suggests that the carrier of the 1600 Å Bump emission is powered by Lyα photons. We argue that the most likely mechanism is Lyα-driven dissociation of H2O in the inner disk, r

  16. A novel method for direct solder bump pull testing using lead-free solders

    Science.gov (United States)

    Turner, Gregory Alan

    This thesis focuses on the design, fabrication, and evaluation of a new method for testing the adhesion strength of lead-free solders, named the Isotraction Bump Pull method (IBP). In order to develop a direct solder joint-strength testing method that did not require customization for different solder types, bump sizes, specific equipment, or trial-and-error, a combination of two widely used and accepted standards was created. First, solder bumps were made from three types of lead free solder were generated on untreated copper PCB substrates using an in-house fabricated solder bump-on-demand generator, Following this, the newly developed method made use of a polymer epoxy to encapsulate the solder bumps that could then be tested under tension using a high precision universal vertical load machine. The tests produced repeatable and predictable results for each of the three alloys tested that were in agreement with the relative behavior of the same alloys using other testing methods in the literature. The median peak stress at failure for the three solders tested were 2020.52 psi, 940.57 psi, and 2781.0 psi, and were within one standard deviation of the of all data collected for each solder. The assumptions in this work that brittle fracture occurred through the Intermetallic Compound layer (IMC) were validated with the use of Energy-Dispersive X-Ray Spectrometry and high magnification of the fractured surface of both newly exposed sides of the test specimens. Following this, an examination of the process to apply the results from the tensile tests into standard material science equations for the fracture of the systems was performed..

  17. Artificial pinning centers using the barrier layer of ordered nanoporous alumina templates

    DEFF Research Database (Denmark)

    Hallet, X.; Mátéfi-Tempfli, Stefan; Mátéfi-Tempfli, M.

    2009-01-01

    The barrier layer of self-ordered anodized aluminium oxide, which is grown from an aluminium foil, has been revealed by a selective chemical etching of the remaining aluminium. The surface obtained in this way consists of a triangular lattice of bumps with 100nm spacing, and heights of approximat...

  18. Surface planarization of Cu and CuNiSn Micro-bumps embedded in polymer for below 20μm pitch 3DIC applications

    OpenAIRE

    De Preter, Inge; Derakhshandeh, Jaber; Heylen, Nancy; Van Acker, Lut; June Rebibis, Kenneth; Miller, Andy; Beyer, Gerald; Beyne, Eric

    2016-01-01

    Planarization techniques such as Surface planer (better known as Fly-cut) and chemical-mechanical polishing (CMP) can be used to improve the bump roughness and bump height uniformity within the die and wafer which can be beneficial for solder based bump stacking and Cu-Cu direct bonding [1]. In this paper the influence of both planarization techniques on 20μm pitch Cu and CuNiSn bumps embedded in polymer are studied. The polymer protects the bumps from the shearing force of the planarization ...

  19. Iron Opacity Bump Changes the Stability and Structure of Accretion Disks in Active Galactic Nuclei

    CERN Document Server

    Jiang, Yan-Fei; Stone, James

    2016-01-01

    Accretion disks around supermassive black holes have regions where the Rosseland mean opacity can be much larger than the electron scattering opacity primarily due to the large number of bound-bound transitions in iron. We study the effects of this iron opacity "bump" on the thermal stability and vertical structure of radiation pressure dominated accretion disks, utilizing three dimensional radiation magneto-hydrodynamic simulations in the local shearing box approximation. The simulations self-consistently calculate the heating due to MHD turbulence caused by magneto-rotational instability and radiative cooling by using the radiative transfer module based on a variable Eddington tensor in Athena. For a $5\\times 10^8$ solar mass black hole with $\\sim 3\\%$ of the Eddington luminosity, a model including the iron opacity bump maintains its structure for more than $10$ thermal times without showing significant signs of thermal runaway. In contrast, if only electron scattering and free-free opacity are included as ...

  20. A'Campo curvature bumps and the Dirac phenomenon near a singular point

    CERN Document Server

    Koike, S; Paunescu, L

    2012-01-01

    The level curves of an analytic function germ almost always have bumps at unexpected points near the singularity. This profound discovery of N. A'Campo is fully explored in this paper for $f(z,w)\\in \\C\\{z,w\\}$, using the Newton-Puiseux infinitesimals and the notion of gradient canyon. Equally unexpected is the Dirac phenomenon: as $c\\ra 0$, the total Gaussian curvature of $f(z,w)=c$ accumulates in the gradient canyons.

  1. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - Little Hales- (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of themultibeam bathymetry of the Charleston Bump off of the...

  2. NOAA TIFF Image - 50m Rugosity, Charleston Bump - Deep Coral Priority Areas - Whiting - (2000), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  3. NOAA TIFF Image - 50m Rugosity, Charleston Bump - Deep Coral Priority Areas - Little Hales - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  4. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  5. NOAA TIFF Image - 50m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Whiting - (2001), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  6. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the 2006 multibeam bathymetry of the Charleston Bump off of the South Atlantic Bight,...

  7. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of the 2006 multibeam bathymetry of the Charleston Bump off of...

  8. NOAA TIFF Image - 50m Singlebeam Slope, Charleston Bump - Deep Coral Priority Areas - Whiting - (2000), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the slope of the Charleston Bump off of the South Atlantic Bight, derived from...

  9. NOAA TIFF Image - 50m Backscatter, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  10. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of the 2006 multibeam bathymetry of the Charleston Bump off of...

  11. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  12. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of the 2006 multibeam bathymetry of the Charleston Bump off...

  13. The instability of viscous self-gravitating protostellar disk affected by density bump

    Science.gov (United States)

    Elyasi, Mahjubeh; Nejad-Asghar, Mohsen

    2017-09-01

    In this work, we study the instability of viscous self-gravitating protostellar disk affected by infalling Low-mass condensations (LMCs) from the envelope of collapsing molecular cloud cores. The infalling low-mass-condensations (LMCs) are considered as density bumps through the nearly Keplerian viscous accretion disk, and their evolutions are analyzed by using the linear perturbation approximation. We investigate occurrence of instability in the evolution of these density bumps. We find the unstable regions of the bumped accretion disk and evaluate the growth time scale (GTS) of the instability. We also study the radial accretion and azimuthal rotation in these unstable regions. The results show that the GTS will be minimum at a special radius so that the unstable regions can be divided in two parts (inner and outer regions). The perturbed radial and azimuthal velocities in the inner unstable regions are strengthened, while in the outer unstable regions are weakened. Decreasing the radial and azimuthal velocities in the outer unstable regions may lead to coagulation of matters. This effect can help the fragmentation of the disk and formation of the self-gravitating bound objects.

  14. Diagnostics on the source properties of type II radio burst with spectral bumps

    CERN Document Server

    Feng, S W; Kong, X L; Li, G; Song, H Q; Feng, X S; Guo, F

    2013-01-01

    In recent studies (Feng et al., 2012; Kong et al., 2012), we proposed that source properties of type II radio bursts can be inferred through a causal relationship between the special shape of the type II dynamic spectrum (e.g., bump or break) and simultaneous extreme ultraviolet (EUV)/white light imaging observations (e.g., CME-shock crossing streamer structures). As a further extension of these studies, in this paper we examine the CME event dated on December 31 2007 associated with a multiple type II radio burst. We identify the presence of two spectral bump features on the observed dynamic spectrum. By combining observational analyses of the radio spectral observations and the EUV-white light imaging data, we conclude that the two spectral bumps are resulted from CME-shock propagating across dense streamers on the southern and northern sides of the CME, respectively. It is inferred that the corresponding two type II emissions originate separately from the two CME-shock flanks where the shock geometries are...

  15. GIANT X-RAY BUMP IN GRB 121027A: EVIDENCE FOR FALL-BACK DISK ACCRETION

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xuefeng [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Hou Shujin [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China); Lei Weihua, E-mail: xfwu@pmo.ac.cn, E-mail: leiwh@hust.edu.cn [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2013-04-20

    A particularly interesting discovery in observations of GRB 121027A is that of a giant X-ray bump detected by the Swift/X-Ray Telescope. The X-ray afterglow re-brightens sharply at {approx}10{sup 3} s after the trigger by more than two orders of magnitude in less than 200 s. This X-ray bump lasts for more than 10{sup 4} s. It is quite different from typical X-ray flares. In this Letter we propose a fall-back accretion model to interpret this X-ray bump within the context of the collapse of a massive star for a long-duration gamma-ray burst. The required fall-back radius of {approx}3.5 Multiplication-Sign 10{sup 10} cm and mass of {approx}0.9-2.6 M{sub Sun} imply that a significant part of the helium envelope should survive through the mass loss during the last stage of the massive progenitor of GRB 121027A.

  16. HST Morphologies of z ~ 2 Dust-Obscured Galaxies II: Bump Sources

    CERN Document Server

    Bussmann, R S; Lotz, J; Armus, L; Brown, M J I; Desai, V; Eisenhardt, P; Higdon, J; Higdon, S; Jannuzi, B T; Floc'h, E Le; Melbourne, J; Soifer, B T; Weedman, D

    2011-01-01

    We present Hubble Space Telescope (HST) imaging of 22 ultra-luminous infrared galaxies (ULIRGs) at z~2 with extremely red R-[24] colors (called dust-obscured galaxies, or DOGs) which have a local maximum in their spectral energy distribution (SED) at rest-frame 1.6um associated with stellar emission. These sources, which we call "bump DOGs", have star-formation rates of 400-4000 Msun/yr and have redshifts derived from mid-IR spectra which show strong polycyclic aromatic hydrocarbon emission --- a sign of vigorous on-going star-formation. Using a uniform morphological analysis, we look for quantifiable differences between bump DOGs, power-law DOGs (Spitzer-selected ULIRGs with mid-IR SEDs dominated by a power-law and spectral features that are more typical of obscured active galactic nuclei than starbursts), sub-millimeter selected galaxies (SMGs), and other less-reddened ULIRGs from the Spitzer extragalactic First Look Survey (XFLS). Bump DOGs are larger than power-law DOGs (median Petrosian radius of 8.4 +/-...

  17. Experiments to measure ablative Richtmyer-Meshkov growth of Gaussian bumps in plastic capsules

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, Eric [Los Alamos National Laboratory; Batha, Steve [Los Alamos National Laboratory; Sedillo, Tom [Los Alamos National Laboratory; Evans, Scott [Los Alamos National Laboratory; Sorce, Chuck [LLE; Landen, Otto [LLNL; Braun, Dave [LLNL

    2010-06-02

    Growth of hydrodynamic instabilities at the interfaces of inertial confinement fusion capsules (ICF) due to ablator and fuel non-uniformities have been of primary concern to the ICF program since its inception. To achieve thermonuclear ignition at Megajoule class laser systems such as the NIF, targets must be designed for high implosion velocities, which requires higher in-flight aspect ratios (IFAR) and diminished shell stability. Controlling capsule perturbations is thus of the utmost importance. Recent simulations have shown that features on the outer surface of an ICF capsule as small as 10 microns wide and 100's of nanometers tall such as bumps, divots, or even dust particles can profoundly impact capsule performance by leading to material jetting or mix into the hotspot. Recent x-ray images of implosions on the NIF may be evidence of such mixing. Unfortunately, our ability to accurately predict these effects is uncertain due to disagreement between equation of state (EOS) models. In light of this, we have begun a campaign to measure the growth of isolated defects (Gaussian bumps) due to ablative Richtmyer-Meshkov in CH capsules to validate these models. The platform that has been developed uses halfraums with radiation temperatures near 75 eV (Rev. 4 foot-level) driven by 15-20 beams from the Omega laser (Laboratory for Laser Energetics, University of Rochester, NY), which sends a ~2.5 Mbar shock into a planar CH foil. Gaussian-shaped bumps (20 microns wide, 4-7 microns tall) are deposited onto the ablation side of the target. On-axis radiography with a saran (Cl Heα - 2.8 keV) backlighter is used to measure bump evolution prior to shock breakout. Shock speed measurements will also be made with Omega's active shock breakout (ASBO) and streaked optical pyrometery (SOP) diagnostics in conjunction with filtered x-ray photodiode arrays (DANTE) to determine drive conditions in the target. These data will be used to discriminate between EOS

  18. Effects of PCB Pad Metal Finishes on the Cu-Pillar/Sn-Ag Micro Bump Joint Reliability of Chip-on-Board (COB) Assembly

    Science.gov (United States)

    Kim, Youngsoon; Lee, Seyong; Shin, Ji-won; Paik, Kyung-Wook

    2016-06-01

    While solder bumps have been used as the bump structure to form the interconnection during the last few decades, the continuing scaling down of devices has led to a change in the bump structure to Cu-pillar/Sn-Ag micro-bumps. Cu-pillar/Sn-Ag micro-bump interconnections differ from conventional solder bump interconnections in terms of their assembly processing and reliability. A thermo-compression bonding method with pre-applied b-stage non-conductive films has been adopted to form solder joints between Cu pillar/Sn-Ag micro bumps and printed circuit board vehicles, using various pad metal finishes. As a result, various interfacial inter-metallic compounds (IMCs) reactions and stress concentrations occur at the Cu pillar/Sn-Ag micro bumps joints. Therefore, it is necessary to investigate the influence of pad metal finishes on the structural reliability of fine pitch Cu pillar/Sn-Ag micro bumps flip chip packaging. In this study, four different pad surface finishes (Thin Ni ENEPIG, OSP, ENEPIG, ENIG) were evaluated in terms of their interconnection reliability by thermal cycle (T/C) test up to 2000 cycles at temperatures ranging from -55°C to 125°C and high-temperature storage test up to 1000 h at 150°C. The contact resistances of the Cu pillar/Sn-Ag micro bump showed significant differences after the T/C reliability test in the following order: thin Ni ENEPIG > OSP > ENEPIG where the thin Ni ENEPIG pad metal finish provided the best Cu pillar/Sn-Ag micro bump interconnection in terms of bump joint reliability. Various IMCs formed between the bump joint areas can account for the main failure mechanism.

  19. Improved Switching Characteristics of Fast Power MOSFETs Applying Solder Bump Technology

    Directory of Open Access Journals (Sweden)

    Sibylle Dieckerhoff

    2008-01-01

    Full Text Available The impact of a reduced package stray inductance on the switching performance of fast power MOSFETs is discussed applying advanced 3D packaging technologies. Starting from an overview over new packaging approaches, a solder bump technology using a flexible PI substrate is exemplarily chosen for the evaluation. Measurement techniques to determine the stray inductance are discussed and compared with a numerical solution based on the PEEC method. Experimental results show the improvement of the voltage utilization while there is only a slight impact on total switching losses.

  20. Aerodynamic Drag Reduction for a Generic Truck Using Geometrically Optimized Rear Cabin Bumps

    Directory of Open Access Journals (Sweden)

    Abdellah Ait Moussa

    2015-01-01

    Full Text Available The continuous surge in gas prices has raised major concerns about vehicle fuel efficiency, and drag reduction devices offer a promising strategy. In this paper, we investigate the mechanisms by which geometrically optimized bumps, placed on the rear end of the cabin roof of a generic truck, reduce aerodynamic drag. The incorporation of these devices requires proper choices of the size, location, and overall geometry. In the following analysis we identify these factors using a novel methodology. The numerical technique combines automatic modeling of the add-ons, computational fluid dynamics and optimization using orthogonal arrays, and probabilistic restarts. Numerical results showed reduction in aerodynamic drag between 6% and 10%.

  1. Unsteady features of the flow on a bump in transonic environment

    Science.gov (United States)

    Budovsky, A. D.; Sidorenko, A. A.; Polivanov, P. A.; Vishnyakov, O. I.; Maslov, A. A.

    2016-10-01

    The study deals with experimental investigation of unsteady features of separated flow on a profiled bump in transonic environment. The experiments were conducted in T-325 wind tunnel of ITAM for the following flow conditions: P0 = 1 bar, T0 = 291 K. The base flow around the model was studied by schlieren visualization, steady and unsteady wall pressure measurements and PIV. The experimentally data obtained using PIV are analyzed by Proper Orthogonal Decomposition (POD) technique to investigate the underlying unsteady flow organization, as revealed by the POD eigenmodes. The data obtained show that flow pulsations revealed upstream and downstream of shock wave are correlated and interconnected.

  2. The big blue bump and soft X-ray excess of individual quasars

    CERN Document Server

    Haro-Corzo, Sinhue A R; Krongold, Yair

    2008-01-01

    For 11 quasar, we find that the soft X-ray excess component is not prolongation of the Big Blue Bump. Furthermore, adopting a theoretical continuum that is absorbed by the appropriate amount of intrinsic dust, we are able to reconcile this universal theoretical continuum with the UV break and the softness problem. Para 11 quasares, encontramos que el exceso de rayos-X suaves no es una prolongacion de la Gran Joroba Azul. Aun mas, adoptando un continuo ionizante teorico absorbido por una cantidad diversa de polvo intrinseco para cada quasar, podemos reconciliar este continuo teorico con el quiebre UV con el problema de suavidad.

  3. The reminiscence bump without memories: The distribution of imagined word-cued and important autobiographical memories in a hypothetical 70-year-old

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    The reminiscence bump is the disproportionate number of autobiographical memories dating from adolescence and early adulthood. It has often been ascribed to a consolidation of the mature self in the period covered by the bump. Here we stripped away factors relating to the characteristics of autob......The reminiscence bump is the disproportionate number of autobiographical memories dating from adolescence and early adulthood. It has often been ascribed to a consolidation of the mature self in the period covered by the bump. Here we stripped away factors relating to the characteristics...

  4. Failure mechanisms and assembly-process-based solution of FCBGA high lead C4 bump non-wetting

    Institute of Scientific and Technical Information of China (English)

    Li Wenqi; Qiu Yiming; Jin Xing; Wang Lei; Wu Qidi

    2012-01-01

    This paper studies the typical failure modes and failure mechanisms of non-wetting in an FCBGA (flip chip ball grid array) assembly.We have identified that the residual lead and tin oxide layer on the surface of the die bumps as the primary contributor to non-wetting between die bumps and substrate bumps during the chipattach reflow process.Experiments with bump reflow parameters revealed that an optimized reflow dwell time and H2 flow rate in the reflow oven can significantly reduce the amount of lead and tin oxides on the surface of the die bumps,thereby reducing the non-wetting failure rate by about 90%.Both failure analysis results and mass production data validate the non-wetting failure mechanisms identified by this study.As a result of the reflow process optimization,the failure rate associated with non-wetting is significantly reduced,which further saves manufacturing cost and increases capacity utilization.

  5. Numerical Analysis of Warpage Induced by Thermo-Compression Bonding Process of Cu Pillar Bump Flip Chip Package

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Oh Young; Jung, Hoon Sun; Lee, Jung Hoon; Choa, Sung-Hoon [Seoul Nat’l Univ. of Science and Technology, Seoul (Korea, Republic of)

    2017-06-15

    In flip chip technology, the conventional solder bump has been replaced with a copper (Cu) pillar bump owing to its higher input/output (I/O) density, finer pitch, and higher reliability. However, Cu pillar bump technology faces several issues, such as interconnect shorting and higher low-k stress due to stiffer Cu pillar structure when the conventional reflow process is used. Therefore, the thermal compression bonding (TCB) process has been adopted in the flip chip attachment process in order to reduce the package warpage and stress. In this study, we investigated the package warpage induced during the TCB process using a numerical analysis. The warpage of the TCB process was compared with that of the reflow process.

  6. Indium-bump-free antimonide superlattice membrane detectors on a silicon substrates

    Science.gov (United States)

    Zamiri, M.; Klein, B.; Schuler, T.; Myers, S.; Cavallo, F.; Krishna, S.

    2016-05-01

    We present an approach to realize antimonide based superlattices on silicon substrates without using conventional Indium-bump hybridization. In this approach, PIN based superlattice detectors are grown on top of a 60 nm Al0.6Ga0.4Sb sacrificial layer on a GaSb host substrate. Following the growth, the individual pixels are transferred using our epitaxiallift off technique, which consists of a wet-etch to undercut the pixels followed by a dry-stamp process to transfer the pixels to a silicon substrate prepared with a gold layer. Structural and optical characterization of the transferred pixels was done using an optical microscope, scanning electron microscopy and photoluminescence. The interface between the transferred pixels and the new substrate was abrupt and no significant degradation in the optical quality was observed. An Indium-bump-free membrane detector was then fabricated using this approach. Spectral response measurements provided a 100% cut-off wavelength of 4.3 μm at 77 K. The performance of the membrane detector was compared to a control detector on the as-grown substrate. The membrane detector was limited by surface leakage current. The proposed approach could pave the way for wafer-level integration of photonic detectors on silicon substrates, which could dramatically reduce the cost of these detectors.

  7. Miniaturization of Micro-Solder Bumps and Effect of IMC on Stress Distribution

    Science.gov (United States)

    Choudhury, Soud Farhan; Ladani, Leila

    2016-07-01

    As the joints become smaller in more advanced packages and devices, intermetallic (IMCs) volume ratio increases, which significantly impacts the overall mechanical behavior of joints. The existence of only a few grains of Sn (Tin) and IMC materials results in anisotropic elastic and plastic behavior which is not detectable using conventional finite element (FE) simulation with average properties for polycrystalline material. In this study, crystal plasticity finite element (CPFE) simulation is used to model the whole joint including copper, Sn solder and Cu6Sn5 IMC material. Experimental lap-shear test results for solder joints from the literature were used to validate the models. A comparative analysis between traditional FE, CPFE and experiments was conducted. The CPFE model was able to correlate the experiments more closely compared to traditional FE analysis because of its ability to capture micro-mechanical anisotropic behavior. Further analysis was conducted to evaluate the effect of IMC thickness on stress distribution in micro-bumps using a systematic numerical experiment with IMC thickness ranging from 0% to 80%. The analysis was conducted on micro-bumps with single crystal Sn and bicrystal Sn. The overall stress distribution and shear deformation changes as the IMC thickness increases. The model with higher IMC thickness shows a stiffer shear response, and provides a higher shear yield strength.

  8. Ultra-fast Movies Resolve Ultra-short Pulse Laser Ablation and Bump Formation on Thin Molybdenum Films

    Science.gov (United States)

    Domke, Matthias; Rapp, Stephan; Huber, Heinz

    For the monolithic serial interconnection of CIS thin film solar cells, 470 nm molybdenum films on glass substrates must be separated galvanically. The single pulse ablation with a 660 fs laser at a wavelength of 1053 nm is investigated in a fluence regime from 0.5 to 5.0 J/cm2. At fluences above 2.0 J/cm2 bump and jet formation can be observed that could be used for creating microstructures. For the investigation of the underlying mechanisms of the laser ablation process itself as well as of the bump or jet formation, pump probe microscopy is utilized to resolve the transient ablation behavior.

  9. The eddy current induced in the pulsed bump magnet for the CSNS/RCS injection%The eddy current induced in the pulsed bump magnet for the CSNS/RCS injection

    Institute of Scientific and Technical Information of China (English)

    宋金星; 康文; 霍丽华; 郝耀斗; 王磊

    2011-01-01

    The injecton pulsed bending bump magnets of Rapid Cycling Synchrotron (RCS) in China Spalla- tion Neutron Source (CSNS) consist of four horizontal bending (BH) magnets and four vertical bending (BV) magnets. The BH magnets are operated at a repetition rat

  10. Investigation of turbulent boundary layer flow over 2D bump using highly resolved large eddy simulation

    DEFF Research Database (Denmark)

    Cavar, Dalibor; Meyer, Knud Erik

    2011-01-01

    A large eddy simulation (LES) study of turbulent non-equilibrium boundary layer flow over 2 D Bump, at comparatively low Reynolds number Reh = U∞h/ν = 1950, was conducted. A well-known LES issue of obtaining and sustaining turbulent flow inside the computational domain at such low Re, is addresse...... partially confirm a close interdependency between generation and evolution of internal layers and the abrupt changes in the skin friction, previously reported in the literature. © 2011 American Society of Mechanical Engineers......., showed a good agreement with the available laser Doppler anemometry (LDA) measurements. Analysis of the flow was directly able to identify and confirm the existence of internal layers at positions related to the vicinity of the upstream and downstream discontinuities in the surface curvature and also...

  11. Failure Modes of Lead Free Solder Bumps Formed by Induction Spontaneous Heating Reflow

    Institute of Scientific and Technical Information of China (English)

    Mingyu LI; Hongbo XU; Jongmyung KIM; Hongbae KIM

    2007-01-01

    The shear failure modes and respective failure mechanism of Sn3.5Ag and Sn3.0Ag0.5Cu lead-free solder bumping on Au/Ni/Cu metallization formed by induction spontaneous heating reflow process have been investigated through the shear test after aging at 120℃ for 0, 1, 4, 9 and 16 d. Different typical shear failure behaviors have been found in the loading curves (shear force vs displacement). From the results of interfacial morphology analysis of the fracture surfaces and cross-sections, two main typical failure modes have been identified. The probabilities of the failure modes occurrence are inconsistent when the joints were aged for different times. The evolution of the brittle Ni3Sn4 and Cu-Ni-Au-Sn layers and the grains coarsening of the solder bulk are the basic reasons for the change of shear failure modes.

  12. The eddy current induced in the pulsed bump magnet for the CSNS/RCS injection

    Institute of Scientific and Technical Information of China (English)

    SONG Jin-Xing; KANG Wen; HUO Li-Hua; HAO Yao-Dou; WANG Lei

    2011-01-01

    The injecton pulsed bending bump magnets of Rapid Cycling Synchrotron (RCS) in China Spallar tion Neutron Source (CSNS) consist of four horizontal bending (BH) magnets and four vertical bending (BV)magnets. The BH magnets are operated at a repetition rate of 25 Hz and are excited with a trapezoid rectangle waveform with about 1.6 milliseconds duration. The eddy current is induced in BH magnets and in the end plates it is expected to be large, so the heat generation is of our great concern. In this paper, the eddy current loss of the BH magnet has been investigated and calculated by using a coupling method of 3D electromagnetic and thermal analysis. The accuracy of the analysis is confirmed by testing the prototype BH magnet. The end plate temperature of the BH magnet provided with slit cuts has been decreased obviously and met the requirements.

  13. Nonuniqueness and multi-bump solutions in parabolic problems with the p-Laplacian

    Science.gov (United States)

    Benedikt, Jiří; Girg, Petr; Kotrla, Lukáš; Takáč, Peter

    2016-01-01

    The validity of the weak and strong comparison principles for degenerate parabolic partial differential equations with the p-Laplace operator Δp is investigated for p > 2. This problem is reduced to the comparison of the trivial solution (≡0, by hypothesis) with a nontrivial nonnegative solution u (x , t). The problem is closely related also to the question of uniqueness of a nonnegative solution via the weak comparison principle. In this article, realistic counterexamples to the uniqueness of a nonnegative solution, the weak comparison principle, and the strong maximum principle are constructed with a nonsmooth reaction function that satisfies neither a Lipschitz nor an Osgood standard "uniqueness" condition. Nonnegative multi-bump solutions with spatially disconnected compact supports and zero initial data are constructed between sub- and supersolutions that have supports of the same type.

  14. Solderjet bumping technique used to manufacture a compact and robust green solid-state laser

    Science.gov (United States)

    Ribes, P.; Burkhardt, T.; Hornaff, M.; Kousar, S.; Burkhardt, D.; Beckert, E.; Gilaberte, M.; Guilhot, D.; Montes, D.; Galan, M.; Ferrando, S.; Laudisio, M.; Belenguer, T.; Ibarmia, S.; Gallego, P.; Rodríguez, J. A.; Eberhardt, R.; Tünnermann, A.

    2015-06-01

    Solder-joining using metallic solder alloys is an alternative to adhesive bonding. Laser-based soldering processes are especially well suited for the joining of optical components made of fragile and brittle materials such as glasses, ceramics and optical crystals due to a localized and minimized input of thermal energy. The Solderjet Bumping technique is used to assemble a miniaturized laser resonator in order to obtain higher robustness, wider thermal conductivity performance, higher vacuum and radiation compatibility, and better heat and long term stability compared with identical glued devices. The resulting assembled compact and robust green diode-pumped solid-state laser is part of the future Raman Laser Spectrometer designed for the Exomars European Space Agency (ESA) space mission 2018.

  15. The reminiscence bump for public events: A review of its prevalence and taxonomy of alternative age distributions

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark

    2013-01-01

    , with a number of alternative age distributions seen in the literature. Therefore, I present a taxonomy of these alternative age distributions. Lastly, I discuss the implications of the existing literature regarding the mechanisms underlying the bump and offer suggestions for future research....

  16. The effect of intermetallic compound morphology on Cu diffusion in Sn-Ag and Sn-Pb solder bump on the Ni/Cu Under-bump metallization

    Science.gov (United States)

    Jang, Guh-Yaw; Duh, Jenq-Gong

    2005-01-01

    The eutectic Sn-Ag solder alloy is one of the candidates for the Pb-free solder, and Sn-Pb solder alloys are still widely used in today’s electronic packages. In this tudy, the interfacial reaction in the eutectic Sn-Ag and Sn-Pb solder joints was investigated with an assembly of a solder/Ni/Cu/Ti/Si3N4/Si multilayer structures. In the Sn-3.5Ag solder joints reflowed at 260°C, only the (Ni1-x,Cux)3Sn4 intermetallic compound (IMC) formed at the solder/Ni interface. For the Sn-37Pb solder reflowed at 225°C for one to ten cycles, only the (Ni1-x,Cux)3Sn4 IMC formed between the solder and the Ni/Cu under-bump metallization (UBM). Nevertheless, the (Cu1-y,Niy)6Sn5 IMC was observed in joints reflowed at 245°C after five cycles and at 265°C after three cycles. With the aid of microstructure evolution, quantitative analysis, and elemental distribution between the solder and Ni/Cu UBM, it was revealed that Cu content in the solder near the solder/IMC interface played an important role in the formation of the (Cu1-y,Niy)6Sn5 IMC. In addition, the diffusion behavior of Cu in eutectic Sn-Ag and Sn-Pb solders with the Ni/Cu UBM were probed and discussed. The atomic flux of Cu diffused through Ni was evaluated by detailed quantitative analysis in an electron probe microanalyzer (EPMA). During reflow, the atomic flux of Cu was on the order of 1016-1017 atoms/cm2sec in both the eutectic Sn-Ag and Sn-Pb systems.

  17. Iron Opacity Bump Changes the Stability and Structure of Accretion Disks in Active Galactic Nuclei

    Science.gov (United States)

    Jiang, Yan-Fei; Davis, Shane W.; Stone, James M.

    2016-08-01

    Accretion disks around supermassive black holes have regions where the Rosseland mean opacity can be larger than the electron scattering opacity due to the large number of bound-bound transitions in iron. We study the effects of this iron opacity “bump” on the thermal stability and vertical structure of radiation-pressure-dominated accretion disks, utilizing three-dimensional radiation magnetohydrodynamic (MHD) simulations in the local shearing box approximation. The simulations self-consistently calculate the heating due to MHD turbulence caused by magneto-rotational instability and radiative cooling by using the radiative transfer module based on a variable Eddington tensor in Athena. For a 5 × 108 solar mass black hole with ˜3% of the Eddington luminosity, a model including the iron opacity bump maintains its structure for more than 10 thermal times without showing significant signs of thermal runaway. In contrast, if only electron scattering and free-free opacity are included as in the standard thin disk model, the disk collapses on the thermal timescale. The difference is caused by a combination of (1) an anti-correlation between the total optical depth and the midplane pressure, and (2) enhanced vertical advective energy transport. These results suggest that the iron opacity bump may have a strong impact on the stability and structure of active galactic nucleus (AGN) accretion disks, and may contribute to a dependence of AGN properties on metallicity. Since this opacity is relevant primarily in UV emitting regions of the flow, it may help to explain discrepancies between observation and theory that are unique to AGNs.

  18. Interfacial reactions and compound formation of Sn-Ag-Cu solders by mechanical alloying on electroless Ni-P/Cu under bump metallization

    Science.gov (United States)

    Kao, Szu-Tsung; Duh, Jenq-Gong

    2005-08-01

    Electroless Ni-P under bump metallization (UBM) has been widely used in electronic interconnections due to the good diffusion barrier between Cu and solder. In this study, the mechanical alloying (MA) process was applied to produce the SnAgCu lead-free solder pastes. Solder joints after annealing at 240°C for 15 min were employed to investigate the evolution of interfacial reaction between electroless Ni-P/Cu UBM and SnAgCu solder with various Cu concentrations ranging from 0.2 to 1.0 wt.%. After detailed quantitative analysis with an electron probe microanalyzer, the effect of Cu content on the formation of intermetallic compounds (IMCs) at SnAgCu solder/electroless Ni-P interface was evaluated. When the Cu concentration in the solder was 0.2 wt.%, only one (Ni, Cu)3Sn4 layer was observed at the solder/electroless Ni-P interface. As the Cu content increased to 0.5 wt.%, (Cu, Ni)6Sn5 formed along with (Ni, Cu)3Sn4. However, only one (Cu, Ni)6Sn5 layer was revealed, if the Cu content was up to 1 wt.%. With the aid of microstructure evolution, quantitative analysis, and elemental distribution by x-ray color mapping, the presence of the Ni-Sn-P phase and P-rich layer was evidenced.

  19. Bump evolution driven by the x-ray ablation Richtmyer-Meshkov effect in plastic inertial confinement fusion Ablators

    Directory of Open Access Journals (Sweden)

    Loomis Eric

    2013-11-01

    Full Text Available Growth of hydrodynamic instabilities at the interfaces of inertial confinement fusion capsules (ICF due to ablator and fuel non-uniformities are a primary concern for the ICF program. Recently, observed jetting and parasitic mix into the fuel were attributed to isolated defects on the outer surface of the capsule. Strategies for mitigation of these defects exist, however, they require reduced uncertainties in Equation of State (EOS models prior to invoking them. In light of this, we have begun a campaign to measure the growth of isolated defects (bumps due to x-ray ablation Richtmyer-Meshkov in plastic ablators to validate these models. Experiments used hohlraums with radiation temperatures near 70 eV driven by 15 beams from the Omega laser (Laboratory for Laser Energetics, University of Rochester, NY, which sent a ∼1.25Mbar shock into a planar CH target placed over one laser entrance hole. Targets consisted of 2-D arrays of quasi-gaussian bumps (10 microns tall, 34 microns FWHM deposited on the surface facing into the hohlraum. On-axis radiography with a saran (Cl Heα − 2.76keV backlighter was used to measure bump evolution prior to shock breakout. Shock speed measurements were also performed to determine target conditions. Simulations using the LEOS 5310 and SESAME 7592 models required the simulated laser power be turned down to 80 and 88%, respectively to match observed shock speeds. Both LEOS 5310 and SESAME 7592 simulations agreed with measured bump areal densities out to 6 ns where ablative RM oscillations were observed in previous laser-driven experiments, but did not occur in the x-ray driven case. The QEOS model, conversely, over predicted shock speeds and under predicted areal density in the bump.

  20. Maximal loads acting on legs of powered roof support unit in longwalls with bumping hazards

    Institute of Scientific and Technical Information of China (English)

    StanislawSzweda

    2001-01-01

    In the article the results of measurements of the resultant force in the legs of a powered roof support unit, caused by a dynamic interaction bf the rock mass, are discussed. The measurements have been taken in the Iongwalls mined with a roof fall, characterized by the highest degree of bumping hazard. It has been stated that the maximal force in the legs Fro, recorded during a dynamic interaction of the rock mass, is proportional to the initial static force in the legs Fst.p Therefore a need for a careful selection of the initial load of the powered roof support, according to the local mining and geological conditions, results from such a statement. Setting the legs with the supporting load exceeding the indispensable value for keeping the direct roof solids in balance, deteriorating the operational parameters of a Iongwall system also has a disadvantageous influence on the value of the force in the legs and the rate of its increase, caused by a dynamic interaction of the rock mass. A correct selection of the initial load causes a decrease in the intensity of a dynamic interaction of the rock mass on powered roof supports, which also has an advanta igeous influence on their life, Simultaneously with the measurements of the resultant force in the legs, the vertical acceleration of the canopy was also recorded. It has enabled to prove that the external dynamic forces may act on the unit both from the roof as well as from the floor. The changes of the force in the legs caused by dynamic phenomena intrinsically created in the roof and changes of the force in the legs caused by blasting explosives in the roof of the working, have been analyzed separately. It has been stated that an increase in the loads of legs, caused by intrinsic phenomena is significantly higher than a force increase in the legs caused by blasting. It means that powered roof supports, to be operated in the workings, where the bumping hazard occurs, will also transmit the loads acting on a unit

  1. NEOS Data and the Origin of the 5 MeV Bump in the Reactor Antineutrino Spectrum

    Science.gov (United States)

    Huber, Patrick

    2017-01-01

    We perform a combined analysis of recent NEOS and Daya Bay data on the reactor antineutrino spectrum. This analysis includes approximately 1.5 million antineutrino events, which is the largest neutrino event sample analyzed to date. We use a double ratio which cancels flux model dependence and related uncertainties as well as the effects of the detector response model. We find at 3-4 standard deviation significance level, that plutonium-239 and plutonium-241 are disfavored as the single source for the so-called 5 MeV bump. This analysis method has general applicability and, in particular, with higher statistics data sets, will be able to shed significant light on the issue of the bump. With some caveats, this should also allow us to improve the sensitivity for sterile neutrino searches in NEOS.

  2. A Tale of Two Mysteries in Interstellar Astrophysics: The 2175 Angstrom Extinction Bump and Diffuse Interstellar Bands

    CERN Document Server

    Xiang, F Y; Zhong, J X

    2012-01-01

    The diffuse interstellar bands (DIBs) are ubiquitous absorption spectral features arising from the tenuous material in the space between stars -- the interstellar medium (ISM). Since their first detection nearly nine decades ago, over 400 DIBs have been observed in the visible and near-infrared wavelength range in both the Milky Way and external galaxies, both nearby and distant. However, the identity of the species responsible for these bands remains as one of the most enigmatic mysteries in astrophysics. An equally mysterious interstellar spectral signature is the 2175 Angstrom extinction bump, the strongest absorption feature observed in the ISM. Its carrier also remains unclear since its first detection 46 years ago. Polycyclic aromatic hydrocarbon (PAH) molecules have long been proposed as a candidate for DIBs as their electronic transitions occur in the wavelength range where DIBs are often found. In recent years, the 2175 Angstrom extinction bump is also often attributed to the \\pi--\\pi* transition in ...

  3. High-order integral equation methods for problems of scattering by bumps and cavities on half-planes

    CERN Document Server

    Pérez-Arancibia, Carlos

    2014-01-01

    This paper presents high-order integral equation methods for evaluation of electromagnetic wave scattering by dielectric bumps and dielectric cavities on perfectly conducting or dielectric half-planes. In detail, the algorithms introduced in this paper apply to eight classical scattering problems, namely: scattering by a dielectric bump on a perfectly conducting or a dielectric half-plane, and scattering by a filled, overfilled or void dielectric cavity on a perfectly conducting or a dielectric half-plane. In all cases field representations based on single-layer potentials for appropriately chosen Green functions are used. The numerical far fields and near fields exhibit excellent convergence as discretizations are refined--even at and around points where singular fields and infinite currents exist.

  4. Does recall of a past music event invoke a reminiscence bump in young adults?

    Science.gov (United States)

    Schubert, Emery

    2016-08-01

    Many studies of the reminiscence bump (RB) in music invoke memories from different autobiographical times by using stimulus specific prompts (SSPs). This study investigated the utility of a non-SSP paradigm to determine whether the RB would emerge when participants were asked to recall a single memorable musical event from "a time long ago". The presence of a RB in response to music has not been obtained in such a manner for younger participants. Eighty-eight 20-22 year olds reported music episodes that peaked when their autobiographical age was 13-14 years. Self-selected stimuli included a range of musical styles, including classical and non-Western pop forms, such as J-pop and K-pop, as well as generational pop music, such as the Beatles. However, most participants reported pop/rock music that was contemporaneous with encoding age, providing support for the utility of published SSP paradigms using pop music. Implications for and limitations of SSP paradigms are discussed. Participants were also asked to relate the selected musical piece to current musical tastes. Most participants liked the music that they selected, with many continuing to like the music, but most also reported a general broadening of their taste, consistent with developmental literature on open-earedness.

  5. GRB 110530A: Peculiar Broad Bump and Delayed Plateau in Early Optical Afterglows

    Science.gov (United States)

    Zhong, Shu-Qing; Xin, Li-Ping; Liang, En-Wei; Wei, Jian-Yan; Urata, Yuji; Huang, Kui-Yun; Qiu, Yu-Lei; Deng, Can-Min; Wang, Yuan-Zhu; Deng, Jin-Song

    2016-11-01

    We report our very early optical observations of GRB 110530A and investigate its jet properties together with its X-ray afterglow data. A peculiar broad onset bump followed by a plateau is observed in its early R band afterglow light curve. The optical data in the other bands and the X-ray data are well consistent with the temporal feature of the R band light curve. Our joint spectral fits of the optical and X-ray data show that they are in the same regime, with a photon index of ∼1.70. The optical and X-ray afterglow light curves are well fitted with the standard external shock model by considering a delayed energy injection component. Based on our modeling results, we find that the radiative efficiency of the gamma-ray burst jet is ∼ 1 % and the magnetization parameter of the afterglow jet is \\lt 0.04 with a derived extremely low {ε }B (the ratio of shock energy to the magnetic field) of (1.64+/- 0.25)× {10}-6. These results indicate that the jet may be matter dominated. A discussion on delayed energy injection from the accretion of the late fall-back material of its pre-supernova star is also presented.

  6. Using a shock control bump to improve the performance of an axial compressor blade section

    Science.gov (United States)

    Mazaheri, K.; Khatibirad, S.

    2017-03-01

    Here, we use numerical analysis to study the effects of a shock control bump (SCB) on the performance of a transonic axial compressor blade section and to optimize its shape and location to improve the compressor performance. A section of the NASA rotor 67 blade is used for this study. Two Bézier curves, each consisting of seven control points, are used to model the suction and pressure surfaces of the blade section. The SCB is modeled with the Hicks-Henne function and, using five design parameters, is added to the suction side. The total pressure loss through a cascade of blade sections is selected as the cost function. A continuous adjoint optimization method is used along with a RANS solver to find a new blade section shape. A grid independence study is performed, and all optimization and flow solver algorithms are validated. Two single-point optimizations are performed in the design condition and in an off-design condition. It is shown that both optimized shapes have overall better performance for both on-design and off-design conditions. An analysis is given regarding how the SCB has changed the wave structure between blade sections resulting in a more favorable flow pattern.

  7. The influential effect of blending, bump, changing period and eclipsing Cepheids on the Leavitt law

    CERN Document Server

    García-Varela, A; Sabogal, B E; Domínguez, S Vargas; Martínez, J

    2016-01-01

    The investigation of the non-linearity of the Leavitt law is a topic that began more than seven decades ago, when some of the studies in this field found that the Leavitt law has a break at about ten days. The goal of this work is to investigate a possible statistical cause of this non-linearity. By applying linear regressions to OGLE-II and OGLE-IV data, we find that, in order to obtain the Leavitt law by using linear regression, robust techniques to deal with influential points and/or outliers are needed instead of the ordinary least-squares regression traditionally used. In particular, by using $M$- and $MM$-regressions we establish firmly and without doubts the linearity of the Leavitt law in the Large Magellanic Cloud, without rejecting or excluding Cepheid data from the analysis. This implies that light curves of Cepheids suggesting blending, bumps, eclipses or period changes, do not affect the Leavitt law for this galaxy. For the SMC, including this kind of Cepheids, it is not possible to find an adequ...

  8. Speed Bumps on the Road to Sustainability - Energy Technology and Geopolitics

    Energy Technology Data Exchange (ETDEWEB)

    Mandil, C.; Taylor, P.; Van Der Linde, C.; Buchner, B.; Ramsay, W.C.; Lipponen, J.; Meier, A.; Berkeley, L.; Di Paola-Galloni, J.L.; Jaureguy-Naudin, M.; Charpin, J.M.; Segar, Ch.; Zaleski, P.; Lesourne, J.; Pires Santos, A.; Menard, D.; Neuhoff, K.; Oettinger, G.

    2011-07-01

    This document gathers the slides of the available presentations given at the 2011 issue of the annual Conference of the Ifri (French Institute of International Relations) Energy Program: 1 - An Energy revolution under way (Peter Taylor, Head of the Energy Technology Division, International Energy Agency); 2 - A look back at Cancun: 'top down' versus 'bottom up' (Barbara Buchner, Director of the CPI - Climate Policy Initiative - Venice office; 3 - CCS: Still in the Starting Blocks? (Juho Lipponen, Head of CCS Unit, International Energy Agency); 4 - Energy Efficiency: Does Anyone Care? (Alan Meier, Senior Scientist and Principal Investigator, Lawrence Berkeley National Laboratory); 5 - The Transport Sector: Anything Goes? (Jean-Luc di Paola-Galloni, Corporate Vice-President, Sustainable Development and External Affairs, Valeo Group); 6 - The Mediterranean Ring: Power or Politics? (Jean-Michel Charpin, Inspecteur General des Finances); 7 - Iran gas and Iraq oil (Chris Segar, Regional Analyst/Middle East and North Africa, International Energy Agency); 8 - Nuclear Power: New Players, New Game, New Rules (Pierre Zaleski, General delegate for the Center of Geopolitics of Energy and Raw Materials, Universite Paris-Dauphine); 9 - The Grid: a Generic Speed Bump (Antonio Pires Santos, Energy and Utilities Industry Leader, Southwest Europe, IBM); 10 - Intellectual Property Rights/Technology transfer (Dominique Menard, Partner, Hogan Lovells (Paris) LLP); 11 - Energy Markets: Conducive to Sustainability (Karsten Neuhoff, Director of the CPI - Climate Policy Initiative - Berlin office, German Institute for Economic Research, DIW Berlin)

  9. Numerical Analysis of Wind Turbine Airfoil Aerodynamic Performance with Leading Edge Bump

    Directory of Open Access Journals (Sweden)

    Majid Asli

    2015-01-01

    Full Text Available Aerodynamic performance improvement of wind turbine blade is the key process to improve wind turbine performance in electricity generated and energy conversion in renewable energy sources concept. The flow behavior on wind turbine blades profile and the relevant phenomena like stall can be improved by some modifications. In the present paper, Humpback Whales flippers leading edge protuberances model as a novel passive stall control method was investigated on S809 as a thick airfoil. The airfoil was numerically analyzed by CFD method in Reynolds number of 106 and aerodynamic coefficients in static angle of attacks were validated with the experimental data reported by Somers in NREL. Therefore, computational results for modified airfoil with sinusoidal wavy leading edge were presented. The results revealed that, at low angles of attacks before the stall region, lift coefficient decreases slightly rather than baseline model. However, the modified airfoil has a smooth stall trend while baseline airfoil lift coefficient decreases sharply due to the separation which occurred on suction side. According to the flow physics over the airfoils, leading edge bumps act as vortex generator so vortices containing high level of momentum make the flow remain attached to the surface of the airfoil at high angle of attack and prevent it from having a deep stall.

  10. GRB 110530A: Peculiar Broad Bump and Delayed Plateau in Early Optical Afterglows

    CERN Document Server

    Zhong, Shu-Qing; Liang, En-Wei; Wei, Jian-Yan; Urata, Yuji; Huang, Kui-Yun; Qiu, Yu-Lei; Deng, Can-Min; Wang, Yuan-Zhu; Deng, Jin-Song

    2016-01-01

    We report our very early optical observations of GRB 110530A and investigate its jet properties together with its X-ray afterglow data. A peculiar broad onset bump followed by a plateau is observed in its early R band afterglow lightcurve. The optical data in the other bands and the X-ray data are well consistent with the temporal feature of the R band lightcurve. Our joint spectral fits of the optical and X-ray data show that they are in the same regime, with a photon index of $\\sim 1.70$. The optical and X-ray afterglow lightcurves are well fitted with the standard external shock model by considering a delayed energy injection component. Based on our modeling results, we find that the radiative efficiency of the GRB jet is $\\sim 1\\%$ and the magnetization parameter of the afterglow jet is $<0.04$ with the derived extremely low $\\epsilon_B$ (the fraction of shock energy to magnetic field) of $(1.64\\pm 0.25)\\times 10^{-6}$. These results indicate that the jet may be matter dominated. Discussion on delayed ...

  11. A Tale of Two Mysteries in Interstellar Astrophysics: The 2175 Å Extinction Bump and Diffuse Interstellar Bands

    Science.gov (United States)

    Xiang, F. Y.; Li, Aigen; Zhong, J. X.

    2011-06-01

    The diffuse interstellar bands (DIBs) are ubiquitous absorption spectral features arising from the tenuous material in the space between stars—the interstellar medium (ISM). Since their first detection nearly nine decades ago, over 400 DIBs have been observed in the visible and near-infrared wavelength range in both the Milky Way and external galaxies, both nearby and distant. However, the identity of the species responsible for these bands remains as one of the most enigmatic mysteries in astrophysics. An equally mysterious interstellar spectral signature is the 2175 Å extinction bump, the strongest absorption feature observed in the ISM. Its carrier also remains unclear since its first detection 46 years ago. Polycyclic aromatic hydrocarbon (PAH) molecules have long been proposed as a candidate for DIBs as their electronic transitions occur in the wavelength range where DIBs are often found. In recent years, the 2175 Å extinction bump is also often attributed to the π-π* transition in PAHs. If PAHs are indeed responsible for both the 2175 Å extinction feature and DIBs, their strengths may correlate. We perform an extensive literature search for lines of sight for which both the 2175 Å extinction feature and DIBs have been measured. Unfortunately, we found no correlation between the strength of the 2175 Å feature and the equivalent widths of the strongest DIBs. A possible explanation might be that DIBs are produced by small free gas-phase PAH molecules and ions, while the 2175 Å bump is mainly from large PAHs or PAH clusters in condensed phase so that there is no tight correlation between DIBs and the 2175 Å bump.

  12. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  13. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  14. NOAA TIFF Image - 30m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  15. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  16. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  17. NOAA TIFF Image - 50m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Little Hales - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  18. NOAA TIFF Image - 50m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Little Hales - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  19. NOAA TIFF Image - 30m Backscatter, Charleston Bump - Deep Coral Priority Areas - NOAA Ship Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  20. Improving Touschek lifetime in ultralow-emittance lattices through systematic application of successive closed vertical dispersion bumps

    Science.gov (United States)

    Breunlin, J.; Leemann, S. C.; Andersson, Å.

    2016-06-01

    In present ultralow-emittance storage ring designs the emittance coupling required for the production of vertically diffraction-limited synchrotron radiation in the hard x-ray regime is achieved and in many cases surpassed by a correction of the orbit and the linear optics alone. However, operating with a vertical emittance lower than required is disadvantageous, since it decreases Touschek lifetime and reduces brightness due to the transverse emittance increase from intrabeam scattering. In this paper we present a scheme consisting of closed vertical dispersion bumps successively excited in each arc of the storage ring by skew quadrupoles that couple horizontal dispersion into the vertical plane to a desired level and thereby raise the vertical emittance in a controlled fashion. A systematic approach to vertical dispersion bumps has been developed that suppresses dispersion and betatron coupling in the straight sections in order to maintain a small projected emittance for insertion devices. In this way, beam lifetime can be significantly increased without negatively impacting insertion device source properties and hence brightness. Using simulation results for the MAX IV 3 GeV storage ring including magnet and alignment imperfections we demonstrate that Touschek lifetime can be increased by more than a factor 2 by adjusting the vertical emittance from 1.3 pm rad (after orbit correction) to 8 pm rad (after application of dispersion bumps) using two to three independent skew quadrupole families all the while ensuring deviations from design optics are restrained to a minimum.

  1. Design of main linac emittance tuning bumps for the Compact Linear Collider and the International Linear Collider

    CERN Document Server

    Eliasson, Peder

    2008-01-01

    The installation of elements in the main linac of future linear colliders can only be done with a limited precision. The inevitable misalignments lead to unacceptable emittance growth. Beam-based alignment, e.g., one-to-one correction, dispersion free steering, or ballistic alignment, is necessary to reduce the emittance growth. In some cases, this is, however, not sufficient. For further reduction of the emittance growth, so-called emittance tuning bumps have to be used. A general strategy for the design of emittance tuning bumps has been developed and tested. Simulations suggest that the method can be conveniently used to understand the weaknesses of existing emittance tuning bumps and to significantly improve their performance in terms of, e.g., emittance reduction capability and convergence speed. An example of an application is the design of ten orthogonal knobs that, according to simulations, can reduce the normalized emittance growth in the Compact Linear Collider (CLIC) main linac from 23.8 to 0.34 nm...

  2. Self-Similar Bumps and Wiggles: Isolating the Evolution of the BAO Peak with Power-law Initial Conditions

    CERN Document Server

    Orban, Chris

    2011-01-01

    Motivated by cosmological surveys that demand accurate theoretical modeling of the baryon acoustic oscillation (BAO) feature in galaxy clustering, we analyze N-body simulations in which a BAO-like gaussian bump modulates the linear theory correlation function \\xi_L(r)=(r_0/r)^{n+3} of an underlying self-similar model with initial power spectrum P(k)=A k^n. These simulations test physical and analytic descriptions of BAO evolution far beyond the range of most studies, since we consider a range of underlying power spectra (n=-0.5, -1, -1.5) and evolve simulations to large effective correlation amplitudes (equivalent to \\sigma_8=4-12 for r_bao = 100 Mpc/h). In all cases, non-linear evolution flattens and broadens the BAO bump in \\xi(r) while approximately preserving its area. This evolution resembles a "diffusion" process in which the bump width \\sigma_bao is the quadrature sum of the linear theory width and a length proportional to the rms relative displacement \\Sigma_pair(r_bao}) of particle pairs separated by...

  3. Design of main linac emittance tuning bumps for the Compact Linear Collider and the International Linear Collider

    Directory of Open Access Journals (Sweden)

    Peder Eliasson

    2008-01-01

    Full Text Available The installation of elements in the main linac of future linear colliders can only be done with a limited precision. The inevitable misalignments lead to unacceptable emittance growth. Beam-based alignment, e.g., one-to-one correction, dispersion free steering, or ballistic alignment, is necessary to reduce the emittance growth. In some cases, this is, however, not sufficient. For further reduction of the emittance growth, so-called emittance tuning bumps have to be used. A general strategy for the design of emittance tuning bumps has been developed and tested. Simulations suggest that the method can be conveniently used to understand the weaknesses of existing emittance tuning bumps and to significantly improve their performance in terms of, e.g., emittance reduction capability and convergence speed. An example of an application is the design of ten orthogonal knobs that, according to simulations, can reduce the normalized emittance growth in the Compact Linear Collider (CLIC main linac from 23.8 to 0.34 nm with convergence within two iterations. Four orthogonal knobs have also been designed for the International Linear Collider (ILC. Simulations show that these knobs converge within a single iteration and reduce normalized emittance growth from 3.8 to 0.05 nm.

  4. Control of flow separation on a contour bump by jets in a Mach 1.9 free-stream: An experimental study

    Science.gov (United States)

    Lo, Kin Hing; Zare-Behtash, Hossein; Kontis, Konstantinos

    2016-09-01

    Flow separation control over a three-dimensional contour bump using jet in a Mach 1.9 supersonic free-stream has been experimentally investigated using a transonic/supersonic wind tunnel. Jet total pressure in the range of 0-4 bar was blowing at the valley of the contour bump. Schlieren photography, surface oil flow visualisation and particle image velocimetry measurements were employed for flow visualisation and diagnostics. Experimental results show that blowing jet at the valley of the contour bump can hinder the formation and distort the spanwise vortices. The blowing jet can also reduce the extent of flow separation appears downstream of the bump crest. It was observed that this approach of flow control is more effective when high jet total pressure is employed. It is believed that a pressure gradient is generated as a result of the interaction between the flow downstream of the bump crest and the jet induced shock leads to the downwards flow motion around the bump valley.

  5. Maximal loads acting on legs of powered roof support unit in longwalls with bumping hazards

    Institute of Scientific and Technical Information of China (English)

    Stanislaw Szweda

    2001-01-01

    In the article the results of measurements of the resultant force in th e legs of a powered roof support unit, caused by a dynamic interaction of the ro ck mass, are discussed. The measurements have been taken in the longwalls mined with a roof fall, characterized by the highest degree of bumping hazard. It has been stated that the maximal force in the legs Fm, recorded during a dynam ic interaction of the rock mass, is proportional to the initial static force in the legs Fst,p. Th erefore a need for a careful selection of the initial load of the powered roof s upport, according to the local mining and geological conditions, results from su ch a statement. Setting the legs with the supporting load exceeding the indispen sable value for keeping the direct roof solids in balance, deteriorating the ope rational parameters of a longwall system also has a disadvantageous influence on the value of the force in the legs and the rate of its increase, caused by a dy namic interaction of the rock mass. A correct selection of the initial load caus es a decrease in the intensity of a dynamic interaction of the rock mass on powe red roof supports, which also has an advantageous influence on their life.   Simultaneously with the measurements of the resultant force in the legs, the vertical acceleration of the canopy was also recorded. It has enabled to prove that the exte rnal dynamic forces may act on the unit both from the roof as well as from the f loor. The changes of the force in the legs caused by dynamic phenomena intrinsic ally created in the roof and changes of the force in the legs caused by blasting explosives in the roof of the working, have been analyzed separately. It has been stated that an increase in the loads of legs, caused by intrinsi c phenomena is significantly higher than a force increase in the legs caused by blasting. It means that powered roof supports, to be operated in the workings, w here the bumping hazard occurs, will also transmit the loads

  6. Sputtered Ni-Zn under bump metallurgy (UBM) for Sn-Ag-Cu solders

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Jin; Kim, Young Min [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Kim, Young-Ho, E-mail: kimyh@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Ni-Zn UBM can effectively suppress the growth of IMCs and the consumption of UBM. Black-Right-Pointing-Pointer The growth of (Ni, Cu){sub 3}Sn{sub 4} was retarded at the SAC305/Ni-Zn interface after aging. Black-Right-Pointing-Pointer Only a single (Cu, Ni){sub 6}Sn{sub 5} formed at the SAC107/Ni-Zn interface after aging. Black-Right-Pointing-Pointer Segregated Zn atoms on IMC layers retarded the interdiffusion of Cu, Ni, and Sn. Black-Right-Pointing-Pointer Sputtered Ni-Zn UBM is promising for Pb-free solder flip chip applications. - Abstract: We developed a new sputtered under bump metallurgy (UBM) based on Ni-20wt% Zn thin films for Pb-free solders. This study focuses on the interfacial reactions between two Pb-free solders (Sn3.0Ag0.5Cu and Sn1.0Ag0.7Cu) and a Ni-Zn alloy UBM. By adding Zn to Ni UBM, Zn is incorporated into intermetallic compounds (IMCs) to form a quaternary Cu-Ni-Zn-Sn phase at the solder/Ni-Zn interface after reflow and subsequent isothermal aging. The Ni-Zn UBM sufficiently reduces the interfacial reaction and IMCs formation rates as well as UBM consumption rates compared to a Ni UBM. In particular, the formation of (Ni, Cu){sub 3}Sn{sub 4} IMC was significantly retarded by adding Zn into UBM.

  7. Characteristics of Laser Reflow Bumping of Sn3.5Ag and Sn3.5Ag0.5Cu Lead-Free Solder Balls

    Institute of Scientific and Technical Information of China (English)

    Yanhong TIAN; Chunqing WANG; Yarong CHEN

    2008-01-01

    Lead-free Sn3.5Ag and Sn3.5Ag0.5Cu solder balls were reflowed by laser to form solder bumps. Shear test was performed on the solder bumps, and SEM/EDX (scanning electron microscopy/energy dispersive X-ray spectrometer) was used to analyze the formation of intermetallic compounds (IMCs) at interface region. A finite element modeling on the temperature gradient and distribution at the interface of solder bump during laser reflow process was conducted to elucidate the mechanism of the IMCs growth direction. The results show that the parameters window for laser reflow bumping of Sn3.5Ag0.5Cu was wider than that of Sn3.5Ag. The shear strength of Sn3.5Ag0.5Cu solder bump was comparable to that of Sn3.5Ag solder bump, and was not affected obviously by laser power and irradiation time when appropriate parameters were used. Both laser power and heating time had a significant effect on the formation of IMCs. A continuous AuSn4 interrnetallic compound layer and some needle-like AuSn4 were observed at the interface of solder and Au/Ni/Cu metallization layer when the laser power is small. The formation of needle-like AuSn4 was due to temperature gradient at the interface, and the direction of temperature gradient was the preferred growth direction of AuSn4. With increasing the laser power and heating time, the needle-like AuSn4 IMCs dissolved into the bulk solder, and precipitated out once again during solidification along the grain boundary of the solder bump.

  8. A new modal-based approach for modelling the bump foil structure in the simultaneous solution of foil-air bearing rotor dynamic problems

    Science.gov (United States)

    Bin Hassan, M. F.; Bonello, P.

    2017-05-01

    Recently-proposed techniques for the simultaneous solution of foil-air bearing (FAB) rotor dynamic problems have been limited to a simple bump foil model in which the individual bumps were modelled as independent spring-damper (ISD) subsystems. The present paper addresses this limitation by introducing a modal model of the bump foil structure into the simultaneous solution scheme. The dynamics of the corrugated bump foil structure are first studied using the finite element (FE) technique. This study is experimentally validated using a purpose-made corrugated foil structure. Based on the findings of this study, it is proposed that the dynamics of the full foil structure, including bump interaction and foil inertia, can be represented by a modal model comprising a limited number of modes. This full foil structure modal model (FFSMM) is then adapted into the rotordynamic FAB problem solution scheme, instead of the ISD model. Preliminary results using the FFSMM under static and unbalance excitation conditions are proven to be reliable by comparison against the corresponding ISD foil model results and by cross-correlating different methods for computing the deflection of the full foil structure. The rotor-bearing model is also validated against experimental and theoretical results in the literature.

  9. Comparison of thermomigration behaviors between Pb-free flip chip solder joints and microbumps in three dimensional integrated circuits: Bump height effect

    Science.gov (United States)

    Ouyang, Fan-Yi; Jhu, Wei-Cheng

    2013-01-01

    Packaging technology is currently transition from flip chip technology to three dimensional integrated circuits (3D ICs) to meet the requirements of consumer electronic products. Compared to flip chip technology, the dimension of microbumps in 3D ICs is shrunk by a factor of 10. In this study, the behaviors of thermomigration in Pb-free solders of flip chip and 3D ICs are presented. When the bump height is 100 μm in the flip chip samples, the Sn protrusion was observed at the hot end and voids formation at the cold end. However, when the bump height is reduced to 5.8 μm in the 3D IC samples, no significant microstructural evolution of Sn was found; instead, the dissolution of Ni under-bump metallization at hot end was observed. We propose that discrepancy between flip chip solder joints and 3D IC microbumps is mainly attributed to the effect of back stress and the presence of thicker Ni under-bump metallization in the 3D IC packaging. Moreover, the critical temperature gradient in terms of different bump heights is discussed, showing below which there will be no net effect of thermomigration of Sn.

  10. Can the bump in the composite spectrum of GRB 910503 be an emission line feature of gamma-ray bursts?

    Institute of Scientific and Technical Information of China (English)

    Yi-Ping Qin; Fu-Wen Zhang

    2005-01-01

    Appearing in the composite spectral data of BATSE, EGRET and COMPTEL for GRB 910503, there is a bump at around 1600keV. We perform a statistical analysis on the spectral data, trying to find out if the bump could be accounted for by a blue-shifted and significantly broadened rest frame line due to the Doppler effect of an expanding fireball surface. We made an F-test and adopted previously proposed criteria. The study reveals that the criteria are well satisfied and the feature can be interpreted as the blue shifted 6.4 keV line. From the fit with this line taken into account, we find the Lorentz factor of this source to be Γ = 116+9-9 (at the 68% confident level,△X2 = 1) and the rest frame spectral peak energy to be EO,p= 2.96+0.24-0.18 keV. Although the existence of the emission line feature requires other independent tests to confirm, the analysis suggests that it is feasible to detect emission line features in the high energy range of GRB spectra when taking into account the Doppler effect of fireball expansion.

  11. Electronic spectroscopy of medium-sized polycyclic aromatic hydrocarbons: Implications for the carriers of the 2175 {\\AA} UV bump

    CERN Document Server

    Steglich, M; Rouillé, G; Huisken, F; Mutschke, H; Henning, Th

    2010-01-01

    Mixtures of polycylic aromatic hydrocarbons (PAHs) have been produced by means of laser pyrolysis. The main fraction of the extracted PAHs were primarily medium-sized, up to a maximum size of 38 carbon atoms per molecule. The use of different extraction solvents and subsequent chromatographic fractionation provided mixtures of different size distributions. UV-VIS absorption spectra have been measured at low temperature by matrix isolation spectroscopy and at room temperature with PAHs as film-like deposits on transparent substrates. In accordance with semi-empirical calculations, our findings suggest that large PAHs with sizes around 50 to 60 carbon atoms per molecule could be responsible for the interstellar UV bump at 217.5 nm.

  12. Effect of Joint Scale and Processing on the Fracture of Sn-3Ag-0.5Cu Solder Joints: Application to Micro-bumps in 3D Packages

    Science.gov (United States)

    Talebanpour, B.; Huang, Z.; Chen, Z.; Dutta, I.

    2016-01-01

    In 3-dimensional (3D) packages, a stack of dies is vertically connected to each other using through-silicon vias and very thin solder micro-bumps. The thinness of the micro-bumps results in joints with a very high volumetric proportion of intermetallic compounds (IMCs), rendering them much more brittle compared to conventional joints. Because of this, the reliability of micro-bumps, and the dependence thereof on the proportion of IMC in the joint, is of substantial concern. In this paper, the growth kinetics of IMCs in thin Sn-3Ag-0.5Cu joints attached to Cu substrates were analyzed, and empirical kinetic laws for the growth of Cu6Sn5 and Cu3Sn in thin joints were obtained. Modified compact mixed mode fracture mechanics samples, with adhesive solder joints between massive Cu substrates, having similar thickness and IMC content as actual micro-bumps, were produced. The effects of IMC proportion and strain rate on fracture toughness and mechanisms were investigated. It was found that the fracture toughness G C decreased with decreasing joint thickness ( h Joint). In addition, the fracture toughness decreased with increasing strain rate. Aging also promoted alternation of the crack path between the two joint-substrate interfaces, possibly proffering a mechanism to enhance fracture toughness.

  13. Instability leading to coal bumps and nonlinear evolutionary mechanisms for a coal-pillar-and-roof system

    Energy Technology Data Exchange (ETDEWEB)

    Qin, S.Q.; Jiao, J.J.; Tang, C.A.; Li, Z.G. [Chinese Academy of Sciences, Beijing (China)

    2006-12-15

    This paper studies the unstable mechanisms of the mechanical system that is composed of the stiff hosts (roof and floor) and the coal pillar using catastrophe theory. It is assumed that the roof is an elastic beam and the coal pillar is a strain-softening medium which can be described by the Weibull's distribution theory of strength. It is found that the instability leading to coal bump depends mainly on the system's stiffness ratio k, which is defined as the ratio of the flexural stiffness of the beam to the absolute value of the stiffness at the turning point of the constitutive curve of the coal pillar, and the homogeneity index m or shape parameter of the Weibull's distribution for the coal pillar. The applicability of the cusp catastrophe is demonstrated by applying the equations to the Mentougou coal mine. A non-linear dynamical model, which is derived by considering the time-dependent property of the coal pillar, is used to study the physical prediction of coal bumps. An algorithm of inversion for determining the parameters of the nonlinear dynamical model is suggested for seeking the precursory abnormality from the observed series of roof settlement. A case study of the Muchengjian coal mine is conducted and its nonlinear dynamical model is established from the observation series using the algorithm of inversion. An important finding is that the catastrophic characteristic index D (i.e., the bifurcation set of the cusp catastrophe model) drastically increases to a high peak value and then quickly drops close to instability. From the viewpoint of damage mechanics of coal pillar, a dynamical model of acoustic emission (AE) is established for modeling the AE activities in the evolutionary process of the system. It is revealed that the values of m and the evolutionary path (D = 0 or D not equal 0) of the system have a great impact on the AE activity patterns and characters.

  14. Investigation Of The Effects Of Reflow Profile Parameters On Lead-free Solder Bump Volumes And Joint Integrity

    Science.gov (United States)

    Amalu, E. H.; Lui, Y. T.; Ekere, N. N.; Bhatti, R. S.; Takyi, G.

    2011-01-01

    The electronics manufacturing industry was quick to adopt and use the Surface Mount Technology (SMT) assembly technique on realization of its huge potentials in achieving smaller, lighter and low cost product implementations. Increasing global customer demand for miniaturized electronic products is a key driver in the design, development and wide application of high-density area array package format. Electronic components and their associated solder joints have reduced in size as the miniaturization trend in packaging continues to be challenged by printing through very small stencil apertures required for fine pitch flip-chip applications. At very narrow aperture sizes, solder paste rheology becomes crucial for consistent paste withdrawal. The deposition of consistent volume of solder from pad-to-pad is fundamental to minimizing surface mount assembly defects. This study investigates the relationship between volume of solder paste deposit (VSPD) and the volume of solder bump formed (VSBF) after reflow, and the effect of reflow profile parameters on lead-free solder bump formation and the associated solder joint integrity. The study uses a fractional factorial design (FFD) of 24-1 Ramp-Soak-Spike reflow profile, with all main effects and two-way interactions estimable to determine the optimal factorial combination. The results from the study show that the percentage change in the VSPD depends on the combination of the process parameters and reliability issues could become critical as the size of solder joints soldered on the same board assembly vary greatly. Mathematical models describe the relationships among VSPD, VSBF and theoretical volume of solder paste. Some factors have main effects across the volumes and a number of interactions exist among them. These results would be useful for R&D personnel in designing and implementing newer applications with finer-pitch interconnect.

  15. Active Drag-Reducing Technique Using Bumps on Transonic Wings%跨音速机翼采用鼓包主动减阻技术研究

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Research on shock wave drag-reducing using two dimensional and three dimensional bumps is performed, including comparisons on wings of large aircraft. The mechanism of bump drag-reducing is researched via supercritical airfoil profile, and geometrical shape and location of bump are optimized. The research results show that location, shape and serial distribution of bump have significant effects on drag-reducing for wings. Finally, the drag-reducing technique using bumps is applied to the large aircraft. As a result, the presented technique reduces shock wave drag to a great extent, increases the ratio of lift to drag, and improves aerodynamic efficiency of the aircraft.%对二维、三维鼓包进行激波控制减阻,并在大型客机的机翼上进行了对比研究。在研究鼓包减阻的机理时,采用了超临界翼型,鼓包的几何形状及鼓包位置的优化也进行了研究。研究结果表明,鼓包位置、形状及串列式分布对机翼的减阻影响较大。最后把得到的研究结果应用到大型飞机的激波减阻上,结果表明,该方法能较大程度地减小激波阻力,进而提高飞机的升阻比,提高飞机的气动效率。

  16. Industry Speed Bumps on Local Tobacco Control in Japan? The Case of Hyogo

    Science.gov (United States)

    Yamada, Keiko; Mori, Nagisa; Kashiwabara, Mina; Yasuda, Sakiko; Horie, Rumi; Yamato, Hiroshi; Garçon, Loic; Armada, Francisco

    2015-01-01

    Background Despite being a signatory since 2004, Japan has not yet fully implemented Article 8 of the World Health Organization’s Framework Convention on Tobacco Control regarding 100% protection against exposure to second-hand smoke (SHS). The Japanese government still recognizes designated smoking rooms (DSRs) in public space as a valid control measure. Furthermore, subnational initiatives for tobacco control in Japan are of limited effectiveness. Through an analysis of the Hyogo initiative in 2012, we identified key barriers to the achievement of a smoke-free environment. Methods Using a descriptive case-study approach, we analyzed the smoke-free policy development process. The information was obtained from meeting minutes and other gray literature, such as public records, well as key informant interviews. Results Hyogo Prefecture established a committee to propose measures against SHS, and most committee members agreed with establishing completely smoke-free environments. However, the hospitality sector representatives opposed regulation, and tobacco companies were allowed to make a presentation to the committee. Further, political power shifted against completely smoke-free environments in the context of upcoming local elections, which was an obvious barrier to effective regulation. Throughout the approving process, advocacy by civil society for stronger regulation was weak. Eventually, the ordinance approved by the Prefectural Assembly was even weaker than the committee proposal and included wide exemptions. Conclusions The analysis of Hyogo’s SHS control initiative shed light on three factors that present challenges to implementing tobacco control regulations in Japan, from which other countries can also draw lessons: incomplete national legislation, the weakness of advocacy by the civil society, and the interference of the tobacco industry. PMID:26155758

  17. Investigation of Intrinsic and External Factors Contributing to the Occurrence of Coal Bumps in the Mining Area of Western Beijing, China

    Science.gov (United States)

    Wang, Hongwei; Jiang, Yaodong; Xue, Sheng; Pang, Xufeng; Lin, Zhinan; Deng, Daixin

    2017-04-01

    An investigation has been made to relate the occurrence of coal bumps to specific geological and mining conditions to the mining area of western Beijing. This investigation demonstrates that the high frequency of coal bumps in this area is due to four localized conditions, namely intrinsic coal properties, the presence of overturned strata and thrust faults, high in situ stress and the extraction of coal from island mining faces. Laboratory tests of coal samples indicated that the coals have a short duration of dynamic fracture, high bursting energy and high elastic strain energy, indicating that the coal is intrinsically prone to the occurrence of coal bumps. This investigation has also revealed that there are overturned strata and well-developed large- and medium-scale thrust faults in this area, and the presence of these structures results in plastic flow, severe discontinuities, rapid changes in overburden thickness and dipping of the coal seams. Well-developed secondary fold structures are also present in the axes and limbs of the primary folds. The instability of thrust faults, in combination with large-scale intrusion of igneous rocks, is closely associated with sudden roof breaking and induces sharp variations in electromagnetic radiation (EMR) and micro-seismic signals, which could be used to help predict coal bumps. In situ stress tests in the mining area demonstrate that the maximum and minimum principal stresses are nearly horizontal and that the intermediate principal stress is approximately vertical. The in situ stress level in the area is higher than the average in the Beijing area, North China and mainland China. In addition to the presence of overturned strata and thrust faults and high in situ stress levels, another external factor contributing to the frequency of coal bumps is coal extraction from island mining faces in this area. Island mining faces experience intermittent mining-induced abutment stress when a fault exists at one side of the

  18. Smart parking barrier

    KAUST Repository

    Alharbi, Abdulrazaq M.

    2016-05-06

    Various methods and systems are provided for smart parking barriers. In one example, among others, a smart parking barrier system includes a movable parking barrier located at one end of a parking space, a barrier drive configured to control positioning of the movable parking barrier, and a parking controller configured to initiate movement of the parking barrier, via the barrier drive. The movable parking barrier can be positioned between a first position that restricts access to the parking space and a second position that allows access to the parking space. The parking controller can initiate movement of the movable parking barrier in response to a positive identification of an individual allowed to use the parking space. The parking controller can identify the individual through, e.g., a RFID tag, a mobile device (e.g., a remote control, smartphone, tablet, etc.), an access card, biometric information, or other appropriate identifier.

  19. PARTITION-OPTIMIZED SINGLE EMULSION PARTICLES IMPROVE SUSTAINED RELEASE OF AMPHIPHILIC BUMPED KINASE INHIBITORS TO CONTROL MALARIA TRANSMISSION

    Directory of Open Access Journals (Sweden)

    Christina Yacoob

    2015-11-01

    Full Text Available Amphiphilic molecules are challenging to be incorporatedinto polymeric particles for sustained release due to their significant solubility in both water and organic solvent used in the fabrication process. Here, we investigated an extensive panel of fabrication methods for the incorporation and release of amphiphilic molecules, in particular, novel amphiphilic bumped kinase inhibitors (BKIs. Previously, BKIswere shown to reduce malaria transmission by blocking of gametocyte exflagellation. Prolonged BKI bioavailability for effective transmission blocking is crucial since infectious gametocytes circulate for several weeks inthe mammalian host, well beyond the half-life of BKIs. So far, delivery systems for sustained release of those BKIs have not been successfully formulated yet. Here we demonstrate that out of several delivery vehicles the partition-optimized single emulsion particles are the ideal system for incorporation and sustained release of amphiphilic BKIs. They increased the incorporation greater than 90% through optimized partitioning of amphiphilic molecules to the polymer phase and sustained release of BKIs up to several weeks with a reduction in the initial burst release. Overall this work provides a method for the incorporation and sustained release of amphiphilic BKIs, and can be adapted for other amphiphilic molecules.

  20. X-ray bumps, iron K-alpha lines, and X-ray suppression by obscuring tori in Seyfert galaxies

    Science.gov (United States)

    Krolik, Julian H.; Madau, Piero; Zycki, Piotr T.

    1994-01-01

    We investigate the X-ray spectral properties of unobscured type 1 and obscured type 2 Seyferts as predicted by the unified Seyfert scheme. We consider the reprocessing of X-ray photons by photoelectric absorption, iron fluorescence, and Compton downscattering in the obscuring tori surrounding these active nuclei, and compute by Monte Carlo methods the reprocessed spectra as a function of the viewing angle. Depending on the optical depth and shape of the torus, and on the viewing angle, the X-ray flux can be suppressed by substantial factors when our line of sight is obscured. We show that an immediate consequence of the existence of an obscuring thick torus is the production in the spectra of type 1 Seyfert galaxies of a bump in the continuum above 10-20 keV and an Fe K-alpha line with significant equivalent width. In those type 2 Seyferts for which the hard X-ray spectrum has been substantially suppressed, the equivalent width of the Fe K-alpha line in the transmitted spectrum can be very large.

  1. Laser generation of elliptical nanometre and sub-nanometre bump arrays on NiP/Al data storage disks and their effect on stiction performance.

    Science.gov (United States)

    Pena, A A; Wang, Z B; Zhang, J; Wu, N E; Li, L

    2011-09-07

    Elliptical nano-bumps on nickel-phosphorus coated aluminium (NiP/Al) hard disks were fabricated by a laser texturing system (maximum power 8 W, maximum frequency 300 kHz). By carefully selecting the level of laser power attenuation and defocus offset distance, bump height can be controlled below 6 nm and down to the sub-nanometre scale. This type of laser-induced texture (elliptical shape) on a disk surface is expected to provide better control of the stiction force along with the smallest separation distance between the head slider and the disk. Quantitative modelling based on the classical Hertzian theory for elliptic contacts has been carried out with the purpose of predicting the stiction behaviour of the presented elliptical shaped sub-10 nm bumps. It has been found that an elliptical shape not only reduces the overall stiction performance of the laser texturing zone (LZT) compared to the conventional circular shape but also extends the occurrence of the 'stiction wall' towards the sub-10 nm regime for ultra-low-glide applications.

  2. Lithium abundance in the globular cluster M4: from the turn-off to the red giant branch bump

    Science.gov (United States)

    Mucciarelli, A.; Salaris, M.; Lovisi, L.; Ferraro, F. R.; Lanzoni, B.; Lucatello, S.; Gratton, R. G.

    2011-03-01

    We present Li and Fe abundances for 87 stars in the globular cluster M4, obtained by using high-resolution spectra collected with GIRAFFE at the Very Large Telescope. The targets range from the turn-off up to the red giant branch bump. The Li abundance in the turn-off stars is uniform, with an average value equal to A(Li)= 2.30 ± 0.02 dex (σ= 0.10 dex), consistent with the upper envelope of Li content measured in other globular clusters and in the halo field stars, confirming also for M4 the discrepancy with the primordial Li abundance predicted by Wilkinson Microwave Anisotropy Probe+ big bang nucleosynthesis (WMAP+BBNS). The global behaviour of A(Li) as a function of the effective temperature allows us to identify the two main drops in the Li evolution due to the first dredge-up and to the extra-mixing episode after the red giant branch bump. The measured iron content of M4 results to [Fe/H]=-1.10 ± 0.01 dex (σ= 0.07 dex), with no systematic offsets between dwarf and giant stars. The behaviour of the Li and Fe abundances along the entire evolutionary path is incompatible with theoretical models including pure atomic diffusion, pointing out that an additional turbulent mixing below the convective region needs to be taken into account, able to inhibit the atomic diffusion. The measured value of A(Li) and its homogeneity in the turn-off stars allow us to put strong constraints on the shape of the Li profile inside the M4 turn-off stars. The global behaviour of A(Li) with the effective temperature can be reproduced with different pristine Li abundances, depending on the kind of adopted turbulent mixing. One cannot reproduce the global trend that starts from the WMAP+BBNS A(Li) and adopts the turbulent mixing described by Richard, Michaud & Richer with the same efficiency as that used by Korn et al. to explain the Li content in NGC 6397. In fact, such a solution is not able to well reproduce simultaneously the Li abundance observed in turn-off and red giant branch

  3. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

    are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk......Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... analysis with operational safety management....

  4. Extremal surface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Engelhardt, Netta; Wall, Aron C. [Department of Physics, University of California,Santa Barbara, CA 93106 (United States)

    2014-03-13

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy.

  5. Barriers to screening mammography.

    Science.gov (United States)

    Sarma, Elizabeth A

    2015-01-01

    Breast cancer (BRCA) is the second most commonly diagnosed cancer among women in the USA, and mammography is an effective means for the early detection of BRCA. Identifying the barriers to screening mammography can inform research, policy and practice aiming to increase mammography adherence. A literature review was conducted to determine common barriers to screening mammography adherence. PsycINFO and PubMed databases were searched to identify studies published between 2000 and 2012 that examined barriers associated with reduced mammography adherence. Three thematic groups of barriers, based on social ecology, were identified from the literature: healthcare system-level, social and individual-level barriers. Researchers must consider screening behaviour in context and, therefore, should simultaneously consider each level of barriers when attempting to understand screening behaviour and create interventions to increase mammography adherence.

  6. The reminiscence bump without memories: The distribution of imagined word-cued and important autobiographical memories in a hypothetical 70-year-old

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2016-01-01

    of autobiographical memories per se, most notably factors that aid in their encoding or retention, by asking students to generate imagined word-cued and imagined ‘most important’ autobiographical memories of a hypothetical, prototypical 70-year-old of their own culture and gender. We compared the distribution...... of these fictional memories with the distributions of actual word-cued and most important autobiographical memories in a sample of 61–70-year-olds. We found a striking similarity between the temporal distributions of the imagined memories and the actual memories. These results suggest that the reminiscence bump...

  7. Converse Barrier Certificate Theorems

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2016-01-01

    This paper shows that a barrier certificate exists for any safe dynamical system. Specifically, we prove converse barrier certificate theorems for a class of structurally stable dynamical systems. Other authors have developed a related result by assuming that the dynamical system has neither sing...

  8. The red giant branch phase transition: Implications for the RGB luminosity function bump and detections of Li-rich red clump stars

    CERN Document Server

    Cassisi, Santi; Pietrinferni, Adriano

    2015-01-01

    We performed a detailed study of the evolution of the luminosity of He-ignition stage and of the red giant branch bump luminosity during the red giant branch phase transition for various metallicities. To this purpose we calculated a grid of stellar models that sample the mass range of the transition with a fine mass step equal to ${\\rm 0.01M_\\odot}$. We find that for a stellar population with a given initial chemical composition, there is a critical age (of 1.1-1.2~Gyr) around which a decrease in age of just 20-30 million years causes a drastic drop in the red giant branch tip brightness. We also find a narrow age range (a few $10^7$ yr) around the transition, characterized by the luminosity of the red giant branch bump being brighter than the luminosity of He ignition. We discuss a possible link between this occurrence and observations of Li-rich core He-burning stars.

  9. Skin barrier function

    DEFF Research Database (Denmark)

    2016-01-01

    Renowned experts present the latest knowledge Although a very fragile structure, the skin barrier is probably one of the most important organs of the body. Inward/out it is responsible for body integrity and outward/in for keeping microbes, chemicals, and allergens from penetrating the skin. Since...... the role of barrier integrity in atopic dermatitis and the relationship to filaggrin mutations was discovered a decade ago, research focus has been on the skin barrier, and numerous new publications have become available. This book is an interdisciplinary update offering a wide range of information...... on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...

  10. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work...

  11. Recycler barrier RF buckets

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, C.M.; /Fermilab

    2011-03-01

    The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.

  12. [Vascular endothelial Barrier Function].

    Science.gov (United States)

    Ivanov, A N; Puchinyan, D M; Norkin, I A

    2015-01-01

    Endothelium is an important regulator of selective permeability of the vascular wall for different molecules and cells. This review summarizes current data on endothelial barrier function. Endothelial glycocalyx structure, its function and role in the molecular transport and leukocytes migration across the endothelial barrier are discussed. The mechanisms of transcellular transport of macromolecules and cell migration through endothelial cells are reviewed. Special section of this article addresses the structure and function of tight and adherens endothelial junction, as well as their importance for the regulation of paracellular transport across the endothelial barrier. Particular attention is paid to the signaling mechanism of endothelial barrier function regulation and the factors that influence on the vascular permeability.

  13. Barriers to Effective Listening.

    Science.gov (United States)

    Hulbert, Jack E.

    1989-01-01

    Discusses the following barriers which interfere with listening efficiency: content, speaker, medium, distractions, mindset, language, listening speed, and feedback. Suggests ways to combat these obstacles to accurate comprehension. (MM)

  14. Barriers to SCM implementing

    OpenAIRE

    M.E. Rosli; B. Md Dero; A. R. Ismail; M. N. Ab Rahman

    2008-01-01

    Purpose: This paper explores the barriers faced by Malaysian manufacturing companies in successfullyimplementing the Supply Chain Management (SCM). The study has highlighted some pertinent factorsperforming the barriers that are most frequently reported by the studied companies. Sixteen companies, fromservice and manufacturing companies were studied over a period of two years to assess their SCM practicesthrough survey and interview processes.Design/methodology/approach: This part discusses t...

  15. LATE TIME MULTI-WAVELENGTH OBSERVATIONS OF SWIFT J1644+5734: A LUMINOUS OPTICAL/IR BUMP AND QUIESCENT X-RAY EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Levan, A. J.; Brown, G. C.; Lyman, J. D.; Stanway, E. R. [Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Tanvir, N. R.; Page, K. L.; O’Brien, P. T.; Wiersema, K. [Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH (United Kingdom); Metzger, B. D. [Columbia Astrophysics Laboratory, New York, NY 10027 (United States); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Perley, D. A. [Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Bloom, J. S., E-mail: A.J.Levan@warwick.ac.uk [Astronomy Department, University of California, Berkeley, CA 94720-7450 (United States)

    2016-03-01

    We present late time multi-wavelength observations of Swift J1644+57, suggested to be a relativistic tidal disruption flare (TDF). Our observations extend to >4 years from discovery and show that 1.4 years after outburst the relativistic jet switched off on a timescale less than tens of days, corresponding to a power-law decay faster than t{sup −70}. Beyond this point weak X-rays continue to be detected at an approximately constant luminosity of L{sub X} ∼ 5 × 10{sup 42} erg s{sup −1} and are marginally inconsistent with a continuing decay of t{sup −5/3}, similar to that seen prior to the switch-off. Host photometry enables us to infer a black hole mass of M{sub BH} = 3 × 10{sup 6} M{sub ⊙}, consistent with the late time X-ray luminosity arising from sub-Eddington accretion onto the black hole in the form of either an unusually optically faint active galactic nucleus or a slowly varying phase of the transient. Optical/IR observations show a clear bump in the light curve at timescales of 30–50 days, with a peak magnitude (corrected for host galaxy extinction) of M{sub R} ∼ −22 to −23. The luminosity of the bump is significantly higher than seen in other, non-relativistic TDFs and does not match any re-brightening seen at X-ray or radio wavelengths. Its luminosity, light curve shape, and spectrum are broadly similar to those seen in superluminous supervnovae, although subject to large uncertainties in the correction of the significant host extinction. We discuss these observations in the context of both TDF and massive star origins for Swift J1644+5734 and other candidate relativistic tidal flares.

  16. Hedging Double Barriers with Singles

    NARCIS (Netherlands)

    Sbuelz, A.

    2000-01-01

    Double barrier options provide risk managers with good-deal flexibility in tailoring portfolio returns.Their hedges offer full protection only if unwound along the barriers.This work provides non-dynamic hedges that project the risk of double barriers on to single barriers.Non-dynamic hedges overcom

  17. Vacuum barrier for excimer lasers

    Energy Technology Data Exchange (ETDEWEB)

    Shurter, Roger P. (Jemez Springs, NM)

    1992-01-01

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput.

  18. Vacuum barrier for excimer lasers

    Energy Technology Data Exchange (ETDEWEB)

    Shurter, R.P.

    1992-09-15

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput. 3 figs.

  19. Barriers to cancer screening.

    Science.gov (United States)

    Womeodu, R J; Bailey, J E

    1996-01-01

    Many barriers to cancer screening have been summarized and discussed. Barriers have been documented in all patient populations, but some groups such as ethnic minorities and the elderly face unique barriers. The barriers to cancer screening, are multifactorial, but much of the responsibility for change must lie with health care providers and the health care delivery industry. This is not to free the patient of all responsibility, but some significant barriers are beyond their direct control. Take, for example, socioeconomic status, disease knowledge, and culturally related perceptions and myths about cancer detection and treatment. The health care industry must do a better job identifying and overcoming these barriers. The significant effects of provider counseling and advice must not be underestimated. Patients must first be advised, and then further actions must be taken if they reject the screening advice. Did they refuse adherence to recommendations because they do not view themselves as susceptible, because of overwhelming personal barriers, or because of a fatalistic attitude toward cancer detection and treatment? If that is the case, physicians and health care institutions must attempt to change perceptions, educate, and personalize the message so that patients accept their disease susceptibility [table: see text]. Multiple patient and provider risk factors have been identified that can be used to target patients particularly at high risk for inadequate cancer screening and providers at high risk for performing inadequate screening. Research has clearly demonstrated the effectiveness of interventions to improve tracking of patient and physician compliance with screening recommendations. Further research is needed to show the impact of managed-care penetration and payer status on screening efforts, and incentive schemes need to be tested that reward institutions and third-party payers who develop uniform standards and procedures for cancer screening. The

  20. Support or Barrier?

    DEFF Research Database (Denmark)

    Sanden, Guro Refsum; Lønsmann, Dorte

    This study offers a critical look at how corporate-level language management influences front-line language practices among employees in three multinational corporations (MNCs) headquartered in Scandinavia. Based on interview and document data, we examine, firstly, what front-line practices emplo...... to a discussion of how a company’s language policy may be seen as both support and a barrier....

  1. Overcoming Language Barriers

    Science.gov (United States)

    De Buda, Yvonne

    1976-01-01

    Many family physicians in Canada experience language and cultural barriers between themselves and their patients. Several aspects of the ensuing problems are described and some practical suggestions for solutions are made. The importance of health education for new Canadians in the family physician's office as well as through the media and community projects is stressed. Imagesp68-ap68-bp70-a PMID:21308059

  2. Barriers to obesity treatment.

    Science.gov (United States)

    Mauro, Marina; Taylor, Valerie; Wharton, Sean; Sharma, Arya M

    2008-05-01

    Obesity, one of the most prevalent health problems in the Western world, is a chronic and progressive condition. Therefore, as with other chronic diseases, patients with obesity require lifelong treatment. Long-term efficacy and effectiveness of obesity treatments is notoriously poor. This may in part be attributable to the substantial barriers that undermine long-term obesity management strategies. These can include lack of recognition of obesity as a chronic condition, low socioeconomic status, time constraints, intimate saboteurs, and a wide range of comorbidities including mental health, sleep, chronic pain, musculoskeletal, cardiovascular, respiratory, digestive and endocrine disorders. Furthermore, medications used to treat some of these disorders may further undermine weight-loss efforts. Lack of specific obesity training of health professionals, attitudes and beliefs as well as coverage and availability of obesity treatments can likewise pose important barriers. Health professionals need to take care to identify, acknowledge and address these barriers where possible to increase patient success as well as compliance and adherence with treatments. Failure to do so may further undermine the sense of failure, low self esteem and self efficacy already common among obese individuals. Addressing treatment barriers can save resources and increase the prospect of long-term success.

  3. C4NP - Lead Free Flip Chip Solder Bumping Manufacturing and Reliability Data%C4NP-无铅倒装晶片焊凸形成生产工艺与可靠性数据

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    受控倒塌芯片连接新工艺是一种由IBM公司开发、由Suss MicroTec公司推向商品化的新型焊凸形成技术.受控倒塌芯片连接新工艺采用各种无铅焊料合金致力于解决现有的凸台.形成技术限定,使低成本小节距焊凸形成成为可能.受控倒塌芯片连接新工艺是一种焊球转移技术,熔焊料被注入预先制成并可重复使用的玻璃模板(模具).这种注满焊料的模具在焊料转入圆片之前先经过检查以确保高成品率.注满焊料的模具与圆片达到精确的接近后以与液态熔剂复杂性无关的简单工序转移在整个300 mm(或300 mm以下)圆片上.受控倒塌芯片连接新工艺技术能够在焊膏印刷中实现小节距凸台形成的同时提供相同合金选择的适应性.这种简单的受控倒塌芯片连接新工艺使低成本、高成品率以及快速封装周期的解决方法对于细节距FCiP以及WLCSP凸台形成均能适用.%C4NP is a new solder bumping technology developed by IBM and commercialized by Suss MicroTec. C4NP addresses the limitations of existing bumping technologies by enabling low-cost, fine pitch bumping using a variety of lead-free solder alloys. C4NP is a solder transfer technology where molten solder is injected into pre-fabricated and reusable glass templates (molds). The filled mold is inspected prior to solder transfer to the wafer to ensure high final yields. Filled mold and wafer are brought into close proximity and solder bumps are transferred onto the entire 300 mm (or smaller)wafer in a single process step without the complexities associated with liquid flux. C4NP technology is capable of fine pitch bumping while offering the same alloy selection flexibility as solder paste printing.The simplicity of the C4NP process makes it a low cost, high yield and fast cycle time solution for both,fine-pitch FCiP as well as WLCSP bumping applications.This paper summarizes the latest manufacturing and reliability data for

  4. Evaluation of 320x240 pixel LEC GaAs Schottky barrier X-ray imaging arrays, hybridized to CMOS readout circuit based on charge integration

    CERN Document Server

    Irsigler, R; Alverbro, J; Borglind, J; Froejdh, C; Helander, P; Manolopoulos, S; O'Shea, V; Smith, K

    1999-01-01

    320x240 pixels GaAs Schottky barrier detector arrays were fabricated, hybridized to silicon readout circuits, and subsequently evaluated. The detector chip was based on semi-insulating LEC GaAs material. The square shaped pixel detector elements were of the Schottky barrier type and had a pitch of 38 mu m. The GaAs wafers were thinned down prior to the fabrication of the ohmic back contact. After dicing, the chips were indium bump, flip-chip bonded to CMOS readout circuits based on charge integration, and finally evaluated. A bias voltage between 50 and 100 V was sufficient to operate the detector. Results on I-V characteristics, noise behaviour and response to X-ray radiation are presented. Images of various objects and slit patterns were acquired by using a standard dental imaging X-ray source. The work done was a part of the XIMAGE project financed by the European Community (Brite-Euram). (author)

  5. Barrier mechanisms in the Drosophila blood-brain barrier

    OpenAIRE

    Samantha Jane Hindle; Roland Jerome Bainton

    2014-01-01

    The invertebrate blood-brain barrier field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through GPCR signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate blood-brain barrier has recently been shown to require coordinated funct...

  6. Geophysical characterization of subsurface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Borns, D.J.

    1995-08-01

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier.

  7. Vacuum barrier for excimer lasers

    Energy Technology Data Exchange (ETDEWEB)

    Shurter, R.P.

    1990-10-10

    This invention is comprised of a barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yearns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput.

  8. [The cultural barrier in care].

    Science.gov (United States)

    Djadaoudjee, Lisa

    2013-11-01

    French cultural diversity is evident within French hospitals, where nurses are confronted with communication problems resulting from the language barrier. While communication is indeed essential, there is another important aspect of caring for a patient for behind the language barrier lies a cultural barrier which must be taken into account in order to provide high-quality care.

  9. Thermal barrier coating materials

    Directory of Open Access Journals (Sweden)

    David R. Clarke

    2005-06-01

    Full Text Available Improved thermal barrier coatings (TBCs will enable future gas turbines to operate at higher gas temperatures. Considerable effort is being invested, therefore, in identifying new materials with even better performance than the current industry standard, yttria-stabilized zirconia (YSZ. We review recent progress and suggest that an integrated strategy of experiment, intuitive arguments based on crystallography, and simulation may lead most rapidly to the development of new TBC materials.

  10. The comprehensive treatment technology of vehicle bumping at bridge head under the bad geological condition%不良地质条件下桥梁桥头跳车的综合处治技术

    Institute of Scientific and Technical Information of China (English)

    常杰

    2012-01-01

    Combining with the specific example, this paper analyzed the root causes of bumping at bridge head phenomenon. Through the use of cement mixed pile foundation, construction of permeable materials, compaction, grouting, setting of bridge head slab and other comprehensive treatment technology to solve the problem of bumping at bridge head, had good using effect, was worth popularizing.%结合具体实例,分析了产生桥头跳车现象的根本原因,通过采用水泥搅拌桩地基、填筑透水性材料、强夯、注浆、设置桥头搭板等综合处治技术解决了桥头跳车难题,使用效果较好,值得推广。

  11. Cold gas and a Milky Way-type 2175 {\\AA} bump in a metal-rich and highly depleted absorption system

    CERN Document Server

    Ma, Jingzhe; Noterdaeme, Pasquier; Ge, Jian; Prochaska, J Xavier; Ji, Tuo; Zhang, Shaohua; Rahmani, Hadi; Jiang, Peng; Schneider, Donald P; Lundgren, Britt; Pâris, Isabelle

    2015-01-01

    We report the detection of a strong Milky Way-type 2175 \\AA$ $ extinction bump at $z$ = 2.1166 in the quasar spectrum towards SDSS J121143.42+083349.7 from the Sloan Digital Sky Survey (SDSS) Data Release 10. We conduct follow up observations with the Echelle Spectrograph and Imager (ESI) onboard the Keck-II telescope and the Ultraviolet and Visual Echelle Spectrograph (UVES) on the VLT. This 2175 \\AA$ $ absorber is remarkable in that we simultaneously detect neutral carbon (C I), neutral chlorine (Cl I), and carbon monoxide (CO). It also qualifies as a damped Lyman alpha system. The J1211+0833 absorber is found to be metal-rich and has a dust depletion pattern resembling that of the Milky Way disk clouds. We use the column densities of the C I fine structure states and the C II/C I ratio (under the assumption of ionization equilibrium) to derive the temperature and volume density in the absorbing gas. A Cloudy photoionization model is constructed, which utilizes additional atoms/ions to constrain the physica...

  12. Uncertainties on near-core mixing in red-clump stars: effects on the period spacing and on the luminosity of the AGB bump

    CERN Document Server

    Bossini, Diego; Salaris, Maurizio; Pietrinferni, Adriano; Montalbán, Josefina; Bressan, Alessandro; Noels, Arlette; Cassisi, Santi; Girardi, Léo; Marigo, Paola

    2015-01-01

    Low-mass stars in the He-core-burning phase (HeCB) play a major role in stellar, galactic, and extragalactic astrophysics. The ability to predict accurately the properties of these stars, however, depends on our understanding of convection, which remains one of the key open questions in stellar modelling. We argue that the combination of the luminosity of the AGB bump (AGBb) and the period spacing of gravity modes (DP) during the HeCB phase, provides us with a decisive test to discriminate between competing models of these stars. We use the MESA, BaSTI, and PARSEC stellar evolution codes to model a typical giant star observed by Kepler. We explore how various near-core-mixing scenarios affect the predictions of the above-mentioned constraints, and we find that DP depends strongly on the prescription adopted. Moreover we show that the detailed behaviour of DP shows the signature of sharp variations in the Brunt-Vaisala frequency, which could potentially give additional information about near-core features. We ...

  13. In situ heating transmission electron microscopy observation of nanoeutectic lamellar structure in Sn-Ag-Cu alloy on Au under-bump metallization.

    Science.gov (United States)

    Seo, Jong-Hyun; Yoon, Sang-Won; Kim, Kyou-Hyun; Chang, Hye-Jung; Lee, Kon-Bae; Seong, Tae-Yeon; Fleury, Eric; Ahn, Jae-Pyoung

    2013-08-01

    We investigated the microstructural evolution of Sn(96.4)Ag(2.8)Cu(0.8) solder through in situ heating transmission electron microscopy observations. As-soldered bump consisted of seven layers, containing the nanoeutectic lamella structure of AuSn and Au₅Sn phases, and the polygonal grains of AuSn₂ and AuSn₄, on Au-plated Cu bond pads. Here, we found that there are two nanoeutectic lamellar layers with lamella spacing of 40 and 250 nm. By in situ heating above 140°C, the nanoeutectic lamella of AuSn and Au₅Sn was decomposed with structural degradation by sphering and coarsening processes of the lamellar interface. At the third layer neighboring to the lamella layer, on the other hand, Au₅Sn particles with a zig-zag shape in AuSn matrix became spherical and were finally dissipated in order to minimize the interface energy between two phases. In the other layers except both lamella layers, polycrystal grains of AuSn₂ and AuSn₄ grew by normal grain growth during in situ heating. The high interface energy of nanoeutectic lamella and polygonal nanograins, which are formed by rapid solidification, acted as a principal driving force on the microstructural change during the in situ heating.

  14. Barrier mechanisms in the Drosophila blood-brain barrier

    Directory of Open Access Journals (Sweden)

    Samantha Jane Hindle

    2014-12-01

    Full Text Available The invertebrate blood-brain barrier field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through GPCR signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate blood-brain barrier has recently been shown to require coordinated function of all layers of the compound barrier structure, analogous to signaling between the layers of the vertebrate neurovascular unit. These findings strengthen the notion that many blood-brain barrier mechanisms are conserved between vertebrates and invertebrates, and suggest that novel findings in invertebrate model organisms will have a significant impact on the understanding of vertebrate BBB functions. In this vein, important roles in coordinating localized and systemic signaling to dictate organism development and growth are beginning to show how the blood-brain barrier can govern whole animal physiologies. This includes novel functions of blood-brain barrier gap junctions in orchestrating synchronized neuroblast proliferation, and of blood-brain barrier secreted antagonists of insulin receptor signaling. These advancements and others are pushing the field forward in exciting new directions. In this review, we provide a synopsis of invertebrate blood-brain barrier anatomy and physiology, with a focus on insights from the past 5 years, and highlight important areas for future study.

  15. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst...

  16. [Barrier methods of contraception].

    Science.gov (United States)

    Goldsmith, A; Edelman, D A

    1982-01-01

    Vaginal methods of contraception were the earliest types used and some references to them date back to antiquity. Most of the vaginal contraceptive agents identified by the ancient Greeks, Indians, Japanese, and Chinese have been found in modern laboratory tests to have spermicidal properties, but it is doubtful that the methods were fully reliable or were used by many people. During the 19th century the condom, vaginal spermicides, and diaphragm became available. The development of nonoxynol-9 and other nonirritating but effective spermicidal agents improved vaginal contraceptives greatly by the 1950s, but starting in the 1960s newer methods began to replace the vaginal methods. Interest in barrier methods has been reawakened somewhat by concern about the health effects of hormonal methods. At present all barrier methods leave something to be desired. Failure rates of 3-30% for barrier methods in general have been estimated, but the higher rates are believed due to incorrect or inconsistent use. Theoretical failure rates of condoms and diaphragms have been estimated at 3/100 women-years, but in actual use failure rates may reach 15 for condoms and 13 for diaphragms used with spermicides. Use-effectiveness rates are greatly influenced by motivation. For a variety of reasons, the acceptability of barrier methods is low, especially in developing countries. New developments in spermicidal agents include sperm inhibitors, which impede the fertilizing capacity of sperm rather than attempting a spermicidal effect; a number of such agents have been studied and have proven more effective in animal tests than conventional spermicides. Neosampoon, a new spermicidal foam, has attracted an increasing number of users, especially in developing countries. A new condom, made of thin polymers and containing a standard dose of nonoxynol-9, has been designed to dissolve in the vaginal fluid. Further studies are needed of its acceptability, efficacy, and side effects before it becomes

  17. Technical barrier challenges

    Institute of Scientific and Technical Information of China (English)

    李思佳

    2014-01-01

    according to a famouse report,the foreign Technical Barriers to Trade(TBT)have some effects on the exports of the People’s Republic of China.Major findings are as follows:(1)TBT makes it more difficult for China to export;(2)TBT increases the costs of Chinese export commodities;(3)TBT causes friction and confilicts in the international trade;(4)SOME developed countries have moved their phase-outs to China and other developing countries,which have become victims of TBT.

  18. Support or Barrier?

    DEFF Research Database (Denmark)

    Sanden, Guro Refsum; Lønsmann, Dorte

    This study offers a critical look at how corporate-level language management influences front-line language practices among employees in three multinational corporations (MNCs) headquartered in Scandinavia. Based on interview and document data, we examine, firstly, what front-line practices...... employees use to cross language boundaries in their everyday work, and, secondly, how these practices relate to top-down language management in the case companies. Our findings show that employees are often dependent on ad hoc and informal solutions in cross- language situations, which leads us...... to a discussion of how a company’s language policy may be seen as both support and a barrier....

  19. Optimum Barrier Height for SiC Schottky Barrier Diode

    OpenAIRE

    Mohamed Abd El-Latif; Alaa El-Din Sayed Hafez

    2013-01-01

    The study of barrier height control and optimization for Schottky barrier diode (SBD) from its physical parameters have been introduced using particle swarm optimization (PSO) algorithm. SBD is the rectifying barrier for electrical conduction across the metal semiconductor (MS) junction and, therefore, is of vital importance to the successful operation of any semiconductor device. 4H-SiC is used as a semiconductor material for its good electrical characteristics with high-power semiconductor ...

  20. 经外侧裂脑池开放减压治疗额颞对冲性脑挫裂伤%Opening cistern combined decompression by transsylvian surgical approach in treatment of severe bump contusion and laceration of brain

    Institute of Scientific and Technical Information of China (English)

    曾昭明; 郭予大; 邵强; 陈秋明; 冯志铁; 吴分浪

    2008-01-01

    Objective To summarize the clinical effects of opening cistern combined decompression of severe bump contusion and laceration of brain by transsylvian surgical approach. Methods Clinical data from 31 cases with severe bump contusion and laceration of brain in the decompression treatment combined with open-ing parasellar and basal cisterns by transsylvian surgical approach was analyzed retrospectively. Results Post- operative did not show visible brain edema in severe bump contusion and laceration of brain,2 cases died of brain exhaustion,2 cases died of severe complications. The Glasgow Outcome Score (COS) was determined at 3-6 months of follow-up for other 27 cases:20 cases had a good recovery,5 cases had moderate disability,2 cases were in a vegetative state. Conclusion Opening cistern combined decompression of severe bump contusion and laceration of brain by transsylvian surgical approach could alleviate secondary brain edema and improve the clin- ical effect for severe bump contusion and laceration of brain.%目的 总结经外侧裂脑池开放在对冲性脑挫裂伤减压术中的应用效果.方法 对31例额颞对冲性脑挫裂伤术中经外侧裂入路施行鞍旁脑池和基底池开放的患者进行临床资料的进行回顾性分析.结果 术后动态复查头颅CT,全部患者额颞脑挫裂伤区域未见明显脑水肿现象,2例死于脑功能衰竭,2例死于严重并发症.其余随访3~6个月,按GOS评分,良好20例,中残5例,植物状生存2例.结论 额颞对冲性脑挫裂伤术中经外侧裂施行鞍旁脑池和基底池开放减压可减轻继发性脑水肿,提高临床效果.

  1. Nanomedicine Faces Barriers

    Directory of Open Access Journals (Sweden)

    Paul Debbage

    2010-10-01

    Full Text Available Targeted nanoparticles have the potential to improve drug delivery efficiencies by more than two orders of magnitude, from the ~ 0.1% which is common today. Most pharmacologically agents on the market today are small drug molecules, which diffuse across the body’s blood-tissue barriers and distribute not only into the lesion, but into almost all organs. Drug actions in the non-lesion organs are an inescapable part of the drug delivery principle, causing “side-effects” which limit the maximally tolerable doses and result in inadequate therapy of many lesions. Nanoparticles only cross barriers by design, so side-effects are not built into their mode of operation. Delivery rates of almost 90% have been reported. This review examines the significance of these statements and checks how far they need qualification. What type of targeting is required? Is a single targeting sufficient? What new types of clinical challenge, such as immunogenicity, might attend the use of targeted nanoparticles?

  2. Higgs vacua behind barriers

    CERN Document Server

    Tamarit, Carlos

    2014-01-01

    Scenarios in which the Higgs vacuum arises radiatively and separated from the origin by a potential barrier at zero temperature are known to be attainable in models with extra singlet scalars, which in the limit of zero barrier height give rise to Coleman-Weinberg realizations of electroweak symmetry breaking. However, this requires large values of Higgs-portal couplings or a large number N of singlets. This is quantified in detail by considering, for varying N, the full two-loop effective potential at zero temperature, as well as finite temperature effects including the dominant two-loop corrections due to the singlets. Despite the large couplings, two-loop effects near the electroweak scale are under control, and actually better behaved in models with larger couplings yet fewer singlets. Strong first-order phase transitions are guaranteed even in the Coleman-Weinberg scenarios. Cubic Higgs couplings and Higgs associated-production cross sections exhibit deviations from the Standard Model predictions which c...

  3. Stability of barrier buckets with zero RF-barrier separations

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.Y.; /Fermilab

    2005-03-01

    A barrier bucket with very small separation between the rf barriers (relative to the barrier widths) or even zero separation has its synchrotron tune decreasing rather slowly from a large value towards the boundary of the bucket. As a result, large area at the bucket edges can become unstable under the modulation of rf voltage and/or rf phase. In addition, chaotic regions may form near the bucket center and extend outward under increasing modulation. Application is made to those barrier buckets used in the process of momentum mining at the Fermilab Recycler Ring.

  4. In Vitro and In Vivo Effects of the Bumped Kinase Inhibitor 1294 in the Related Cyst-Forming Apicomplexans Toxoplasma gondii and Neospora caninum.

    Science.gov (United States)

    Winzer, Pablo; Müller, Joachim; Aguado-Martínez, Adriana; Rahman, Mahbubur; Balmer, Vreni; Manser, Vera; Ortega-Mora, Luis Miguel; Ojo, Kayode K; Fan, Erkang; Maly, Dustin J; Van Voorhis, Wesley C; Hemphill, Andrew

    2015-10-01

    We report on the in vitro effects of the bumped kinase inhibitor 1294 (BKI-1294) in cultures of virulent Neospora caninum isolates Nc-Liverpool (Nc-Liv) and Nc-Spain7 and in two strains of Toxoplasma gondii (RH and ME49), all grown in human foreskin fibroblasts. In these parasites, BKI-1294 acted with 50% inhibitory concentrations (IC50s) ranging from 20 nM (T. gondii RH) to 360 nM (N. caninum Nc-Liv), and exposure of intracellular stages to 1294 led to the nondisjunction of newly formed tachyzoites, resulting in the formation of multinucleated complexes similar to complexes previously observed in BKI-1294-treated N. caninum beta-galactosidase-expressing parasites. However, such complexes were not seen in a transgenic T. gondii strain that expressed CDPK1 harboring a mutation (G to M) in the gatekeeper residue. In T. gondii ME49 and N. caninum Nc-Liv, exposure of cultures to BKI-1294 resulted in the elevated expression of mRNA coding for the bradyzoite marker BAG1. Unlike in bradyzoites, SAG1 expression was not repressed. Immunofluorescence also showed that these multinucleated complexes expressed SAG1 and BAG1 and the monoclonal antibody CC2, which binds to a yet unidentified bradyzoite antigen, also exhibited increased labeling. In a pregnant mouse model, BKI-1294 efficiently inhibited vertical transmission in BALB/c mice experimentally infected with one of the two virulent isolates Nc-Liv or Nc-Spain7, demonstrating proof of concept that this compound protected offspring from vertical transmission and disease. The observed deregulated antigen expression effect may enhance the immune response during BKI-1294 therapy and will be the subject of future studies.

  5. A single mutation in the gatekeeper residue in TgMAPKL-1 restores the inhibitory effect of a bumped kinase inhibitor on the cell cycle

    Directory of Open Access Journals (Sweden)

    Tatsuki Sugi

    2015-04-01

    Full Text Available Toxoplasma gondii is the causative pathogen for Toxoplasmosis. Bumped kinase inhibitor 1NM-PP1 inhibits the growth of T. gondii by targeting TgCDPK1. However, we recently reported that resistance to 1NM-PP1 can be acquired via a mutation in T. gondii mitogen-activated protein kinase like 1 (TgMAPKL-1. Further characterization of how this TgMAPKL-1 mutation restores the inhibitory effect of 1NM-PP1 would shed further light on the function of TgMAPKL-1 in the parasite life cycle. Therefore, we made parasite clones with TgMAPKL-1 mutated at the gatekeeper residue Ser 191, which is critical for 1NM-PP1 susceptibility. Host cell lysis of RH/ku80-/HA-TgMAPKL-1S191A was completely inhibited at 250 nM 1NM-PP1, whereas that of RH/ku80-/HA-TgMAPKL-1S191Y was not. By comparing 1NM-PP1-sensitive (RH/ku80-/HA-TgMAPKL-1S191A and -resistant (RH/ku80-/HA-TgMAPKL-1S191Y clones, we observed that inhibition of TgMAPKL-1 blocked cell cycle progression after DNA duplication. Morphological analysis revealed that TgMAPKL-1 inhibition caused enlarged parasite cells with many daughter cell scaffolds and imcomplete cytokinesis. We conclude that the mutation in TgMAPKL-1 restored the cell cycle-arresting effect of 1NM-PP1 on T. gondii endodyogeny. Given that endodyogeny is the primary mechanism of cell division for both the tachyzoite and bradyzoite stages of this parasite, TgMAPKL-1 may be a promising target for drug development. Exploration of the signals that regulate TgMAPKL-1 will provide further insights into the unique mode of T. gondii cell division.

  6. Silicon Carbide Schottky Barrier Diode

    Science.gov (United States)

    Zhao, Jian H.; Sheng, Kuang; Lebron-Velilla, Ramon C.

    2004-01-01

    This chapter reviews the status of SiC Schottky barrier diode development. The fundamental of Schottky barrier diodes is first provided, followed by the review of high-voltage SiC Schottky barrier diodes, junction-barrier Schottky diodes, and merged-pin-Schottky diodes. The development history is reviewed ad the key performance parameters are discussed. Applications of SiC SBDs in power electronic circuits as well as other areas such as gas sensors, microwave and UV detections are also presented, followed by discussion of remaining challenges.

  7. Translating barriers into potential improvements

    DEFF Research Database (Denmark)

    Altintzoglou, Themistoklis; Hansen, Karina Birch; Valsdottir, Thora

    2010-01-01

    Purpose: The aim of this study is to explore potential barriers to seafood consumption by The aim of this study is to explore potential barriers to seafood consumption by young adults and the parents of young children. Knowledge of these barriers will be used to assist the development of new...... to lead to practical input The present study combines qualitative methods to lead to practical input for NPD focusing on overcoming the barriers that keep consumers from choosing existing healthy seafood products. The importance of the consumers' confidence in their ability to successfully prepare...

  8. Countermeasures and barriers

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Johannes [Oersted - DTU, Automation, Kgs. Lyngby (Denmark)

    2005-10-01

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  9. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst......The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...

  10. Informal export barriers and poverty

    OpenAIRE

    Porto, Guido G.

    2004-01-01

    The author investigates the poverty impacts of informal export barriers like transport costs, cumbersome customs practices, costly regulations, and bribes. He models these informal barriers as export taxes that distort the efficient allocation of resources. In low-income agricultural economies, this distortion lowers wages and household agricultural income, thereby leading to higher pover...

  11. Barriers to Women in Science

    Science.gov (United States)

    Butler, Rosemary

    2013-01-01

    The Presiding Officer of the National Assembly for Wales, Rosemary Butler AM, has put the issue of barriers to women in public life at the top of the political agenda in Wales. She has held sessions with women across Wales to find out what those barriers are and how they can be tackled. On International Women's Day in February, she invited…

  12. Barriers to Women in Science

    Science.gov (United States)

    Butler, Rosemary

    2013-01-01

    The Presiding Officer of the National Assembly for Wales, Rosemary Butler AM, has put the issue of barriers to women in public life at the top of the political agenda in Wales. She has held sessions with women across Wales to find out what those barriers are and how they can be tackled. On International Women's Day in February, she invited…

  13. BARRIERS OF STRATEGIC ALLIANCES ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Vladislav M. Sannikov

    2014-01-01

    Full Text Available General barriers of organization of different types of strategic alliances have beenconsidered in the article. There are several recommendations for overcoming themin cases of international alliances, and in case of work in one state. The article also identified goals and tasks of single coordination center of alliance to overcome organization barriers.

  14. Spanning trees crossing few barriers

    NARCIS (Netherlands)

    Asano, T.; Berg, M. de; Cheong, O.; Guibas, L.J.; Snoeyink, J.; Tamaki, H.

    2002-01-01

    We consider the problem of finding low-cost spanning trees for sets of n points in the plane, where the cost of a spanning tree is defined as the total number of intersections of tree edges with a given set of m barriers. We obtain the following results: (i) if the barriers are possibly intersecting

  15. Epistemological barriers to radical behaviorism.

    Science.gov (United States)

    O'Donohue, W T; Callaghan, G M; Ruckstuhl, L E

    1998-01-01

    The historian and philosopher of science Gaston Bachelard proposed the concept of epistemological barriers to describe the intellectual challenges encountered by scientists in their work. In order to embrace novel ways of approaching a problem in science, scientists must overcome barriers or obstacles posed by their prior views. For example, Einsteinian physics presents scientists with claims that space is curved and that time and space are on the same continuum. We utilize Bachelard's concept of epistemological barriers to describe the differences between the intellectual journeys students pursuing advanced studies face when attempting to accept cognitive psychology or radical behaviorism. We contend that the folk psychological beliefs that students typically hold when entering these studies pose less challenge to cognitive psychology than to radical behaviorism. We also suggest that these barriers may also partly be involved in the problematic exegesis that has plagued radical behaviorism. In close, we offer some suggestions for dealing with these epistemological barriers.

  16. Epistemological barriers to radical behaviorism

    Science.gov (United States)

    O'Donohue, William T.; Callaghan, Glenn M.; Ruckstuhl, L. E.

    1998-01-01

    The historian and philosopher of science Gaston Bachelard proposed the concept of epistemological barriers to describe the intellectual challenges encountered by scientists in their work. In order to embrace novel ways of approaching a problem in science, scientists must overcome barriers or obstacles posed by their prior views. For example, Einsteinian physics presents scientists with claims that space is curved and that time and space are on the same continuum. We utilize Bachelard's concept of epistemological barriers to describe the differences between the intellectual journeys students pursuing advanced studies face when attempting to accept cognitive psychology or radical behaviorism. We contend that the folk psychological beliefs that students typically hold when entering these studies pose less challenge to cognitive psychology than to radical behaviorism. We also suggest that these barriers may also partly be involved in the problematic exegesis that has plagued radical behaviorism. In close, we offer some suggestions for dealing with these epistemological barriers. PMID:22478314

  17. Development of engineered barrier

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  18. Bump bonding of pixel systems

    Energy Technology Data Exchange (ETDEWEB)

    Lozano, M. E-mail: manuel.lozano@cnm.es; Cabruja, E.; Collado, A.; Santander, J.; Ullan, M

    2001-11-01

    A pixel detector consists of an array of radiation sensing elements which is connected to an electronic read-out unit. Many different ways of making this connection between these two different devices are currently being used or considered to be used in the next future. Bonding techniques such as flip chip technology can present real advantages because they allow very fine pitch and a high number of I/Os. This paper presents a review of the different flip chip technologies available and their suitability for manufacturing pixel detectors. The particular problems concerning testing of pixel detectors and thermal issues related to them are pointed out.

  19. Say No to Speed Bumps!

    Science.gov (United States)

    Brannon, Sian

    2010-01-01

    No matter how cutting edge (and nicely funded) one's library is, there is always something cooler and more efficient on the horizon. Granted, not all new technology may be necessary in the library. But chances are one is going to want to get something--RFID (radio frequency identification), text reference, downloadable content, gaming,…

  20. Bump bonding of pixel systems

    CERN Document Server

    Lozano, M; Collado, A; Santander, J; Ullán, M

    2001-01-01

    A pixel detector consists of an array of radiation sensing elements which is connected to an electronic read-out unit. Many different ways of making this connection between these two different devices are currently being used or considered to be used in the next future. Bonding techniques such as flip chip technology can present real advantages because they allow very fine pitch and a high number of I/Os. This paper presents a review of the different flip chip technologies available and their suitability for manufacturing pixel detectors. The particular problems concerning testing of pixel detectors and thermal issues related to them are pointed out.

  1. Say No to Speed Bumps!

    Science.gov (United States)

    Brannon, Sian

    2010-01-01

    No matter how cutting edge (and nicely funded) one's library is, there is always something cooler and more efficient on the horizon. Granted, not all new technology may be necessary in the library. But chances are one is going to want to get something--RFID (radio frequency identification), text reference, downloadable content, gaming,…

  2. A Bump on the Head

    Centers for Disease Control (CDC) Podcasts

    2011-02-15

    In this podcast for kids, the Kidtastics talk about concussions, including how serious they are, symptoms, what to do if you think you have one, and tips for preventing them.  Created: 2/15/2011 by National Center for Injury Prevention and Control (NCIPC).   Date Released: 2/15/2011.

  3. Effect of TiO{sub 2} nanoparticle addition on electroless Ni–P under bump metallization for lead-free solder interconnection

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xiao; Xu, Sha [Department of Electronic Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Yang, Ying; Chen, Zhong [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Chan, Y.C., E-mail: eeycchan@cityu.edu.hk [Department of Electronic Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)

    2014-04-01

    One primary purpose of this study is to introduce an electroless Ni–P–TiO{sub 2} (17.5 at% of P) composite coating as a pad finish for advanced electronic packaging. In this study, TiO{sub 2} nanoparticles were incorporated into the Ni–P layer by electroless deposition and its function as novel under bump metallization (UBM) was intensively investigated. The majority of the added TiO{sub 2} nanoparticles were proved to be uniformly distributed in UBM by scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The interfacial reaction between electrolessly deposited Ni–P–TiO{sub 2} layer and Sn–3.5Ag solder alloy was systematically analyzed. The prime Ni–P UBM was used for comparison to evaluate the effect of TiO{sub 2} nanoparticle on the interfacial microstructure and mechanical property. Both solder/Ni–P and solder/Ni–P–TiO{sub 2} joints were aged at temperature from 150 °C to 190 °C for different aging periods in order to study the intermetallic compounds (IMCs) growth and calculate the activation energy. It was found the growth of Ni{sub 3}Sn{sub 4} IMC layer and the void formation at the reaction interface were successfully suppressed with the help of the TiO{sub 2} nanoparticle. The activation energies for the growth of Ni{sub 3}Sn{sub 4} on Ni–P and Ni–P–TiO{sub 2} layers were calculated to be 50.9 kJ/mol and 55.7 kJ/mol, respectively. The extensive growth of Ni{sub 3}P and Ni–Sn–P phases as well as the consumption rate of the amorphous UBM was controlled in joints with TiO{sub 2} nanoparticles. Thus Ni–P–TiO{sub 2} UBM blocked the Cu diffusion from substrate to interface. A detailed reaction induced diffusion mechanism was proposed. The solder/Ni–P–TiO{sub 2} solder joint consistently demonstrated higher shear strength than solder/Ni–P joint as a function of aging time. TiO{sub 2} nanoparticle contributed to slow down the declining rate of shear strength from 0.021 Mpa/h to 0.013 Mpa/h with the aging time

  4. 华亭煤矿冲击地压监测及防治技术%Monitoring and Measuring of Mine Pressure Bumping and Prevention and Control Technology in Huating Mine

    Institute of Scientific and Technical Information of China (English)

    张玉亮; 徐元强; 李俊; 李守峰

    2012-01-01

    为有效防治华亭煤矿冲击地压,系统分析了矿井冲击地压发生的原因,建立了以微震法为主,声发射、电磁辐射及钻屑检测为辅的冲击地压综合监测和预警管理体系。通过优化工作面布置、煤柱宽度、采放比、推进速度,改善了开采技术条件。采用煤层注水、顶底板深孔爆破、煤体卸压爆破及大直径钻孔等措施,实施主动解危。同时加强巷道支护和个体防护等强化防范措施,使冲击地压对矿井生产的影响时间由每年36 d减少到6 d,保证矿井安全生产。%In order effectively prevent and control the mine pressure bumping occurred in Huating Mine, the cause of the mine pressure bumping occurred was systematically analyzed and a mine pressure comprehensive monitoring and measuring and early warning manage-ment system was established mainly with micro seismic method and secondary with the acoustic emission, electromagnetic radiation and drilling cuttings detection. With the optimization of the coal mining face layout, coal pillar width, mining and caving ratio and the coal mining face advancing rate, the coal mining technology condition was improved. With the application of the seam water injection, the deep borehole blasting in the roof and floor, pressure releasing blasting in seam, the large diameter borehole and other measures, the mine pres- sure bumping danger could be actively released. Meanwhile the mine roadway support was enhanced and the personnel protection and other enhanced prevention measures conducted, the time of the mine pressure bumping affected to the mine production was reduced from 36 days to 6 days per year. The mine safety production could be ensured.

  5. Tritium/hydrogen barrier development

    Energy Technology Data Exchange (ETDEWEB)

    Hollenberg, G.W.; Simonen, E.P. [Pacific Northwest Lab., Richland, WA (United States); Kalinen, G. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany). International Thermonuclear Experimental Reactor (ITER) Team; Terlain, A. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Service de la Corrosion, d`Electrochimie et Chimie des Fluides

    1994-06-01

    A review of hydrogen permeation barriers that can be applied to structural metals used in fusion power plants is presented. Both implanted and chemically available hydrogen isotopes must be controlled in fusion plants. The need for permeation barriers appears strongest in Li17-Pb blanket designs, although barriers also appear necessary for other blanket and coolant systems. Barriers that provide greater than a 1000 fold reduction in the permeation of structural metals are desired. In laboratory experiments, aluminide and titanium ceramic coatings provide permeation reduction factors, PRFS, from 1000 to over 100,000 with a wide range of scatter. The rate-controlling mechanism for hydrogen permeation through these barriers may be related to the number and type of defects in the barriers. Although these barriers appear robust and resistant to liquid metal corrosion, irradiation tests which simulate blanket environments result in very low PRFs in comparison to laboratory experiments, i.e., <150. It is anticipated from fundamental research activities that the REID enhancement of hydrogen diffusion in oxides may contribute to the lower permeation reduction factors during in-reactor experiments.

  6. A LOOK AT CULTURAL BARRIERS

    Directory of Open Access Journals (Sweden)

    Carmen A. VRÂNCEANU

    2015-06-01

    Full Text Available Nowadays the global market allows each individual to work in foreign countries. This fact is a great opportunity for business development, but also puts into light the problem of cultural barriers. Ineffective cross-cultural communication and collaboration can harm employees, customers, and other stakeholders. A company with employees from different cultures must acknowledge and understand these barriers in order to overcome them and to obtain the desired performance. The present study aims to expose the cultural barriers encountered by foreigners in a multinational company from Romania.

  7. Barriers in Concurrent Separation Logic

    Science.gov (United States)

    Hobor, Aquinas; Gherghina, Cristian

    We develop and prove sound a concurrent separation logic for Pthreads-style barriers. Although Pthreads barriers are widely used in systems, and separation logic is widely used for verification, there has not been any effort to combine the two. Unlike locks and critical sections, Pthreads barriers enable simultaneous resource redistribution between multiple threads and are inherently stateful, leading to significant complications in the design of the logic and its soundness proof. We show how our logic can be applied to a specific example program in a modular way. Our proofs are machine-checked in Coq.

  8. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Department of Resources — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...

  9. and use of barrier techniques

    African Journals Online (AJOL)

    Attitudes of Nigerian dentists towards hepatitis B vaccination and use of barrier techniques .... tine screening of only high-risk patients has been recommended.“ .... i337-1342. Sote EO. AIDS and infection Control: experiences, attitudes,.

  10. Barriers for recess physical activity

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper

    2014-01-01

    they would like to have more secluded areas added to the school playground, even in large schoolyards where lack of space was not a barrier. This aligned with girls' requests for more "hanging-out" facilities, whereas boys primarily wanted activity promoting facilities. CONCLUSION: Based on the results from......BACKGROUND: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender....... This was verified by a thematic analysis of transcripts from the open discussions and go-along interviews. RESULTS: The most frequently identified barriers for both boys and girls were weather, conflicts, lack of space, lack of play facilities and a newly-found barrier, use of electronic devices. While boys...

  11. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Department of Resources — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...

  12. Low Conductivity Thermal Barrier Coatings

    Science.gov (United States)

    Zhu, Dong-Ming

    2005-01-01

    Thermal barrier coatings will be more aggressively designed to protect gas turbine engine hot-section components in order to meet future engine higher fuel efficiency and lower emission goals. In this presentation, thermal barrier coating development considerations and requirements will be discussed. An experimental approach is established to monitor in real time the thermal conductivity of the coating systems subjected to high-heat-flux, steady-state and cyclic temperature gradients. Advanced low conductivity thermal barrier coatings have also been developed using a multi-component defect clustering approach, and shown to have improved thermal stability. The durability and erosion resistance of low conductivity thermal barrier coatings have been improved utilizing advanced coating architecture design, composition optimization, in conjunction with more sophisticated modeling and design tools.

  13. Guided tissue regeneration. Absorbable barriers.

    Science.gov (United States)

    Wang, H L; MacNeil, R L

    1998-07-01

    Over the past 15 years, techniques aimed at regeneration of lost periodontal tissue have become widely used and accepted in clinical practice. Among these techniques are those which use the principles of guided tissue regeneration (GTR), wherein barriers (i.e., membranes) are used to control cell and tissue repopulation of the periodontal wound. A variety of non-absorbable and absorbable barriers have been developed and used for this purpose, with a trend in recent years toward increased use of absorbable GTR materials. This article describes the evolution of absorbable barrier materials and overview materials available for clinical use today. In addition, advantages and disadvantages of these materials are discussed, as well as possible new developments in barrier-based GTR therapy.

  14. Nonlocal reflection by photonic barriers

    OpenAIRE

    Vetter, R. -M.; A. Haibel; Nimtz, G.

    2001-01-01

    The time behaviour of microwaves undergoing partial reflection by photonic barriers was measured in the time and in the frequency domain. It was observed that unlike the duration of partial reflection by dielectric layers, the measured reflection duration of barriers is independent of their length. The experimental results point to a nonlocal behaviour of evanescent modes at least over a distance of some ten wavelengths. Evanescent modes correspond to photonic tunnelling in quantum mechanics.

  15. Schooling Inequality and Language Barriers

    OpenAIRE

    Parker, Susan W.; Rubalcava, Luis; Teruel, Graciela

    2005-01-01

    This article estimates the impact of language barriers on school achievement and the potential ameliorating role of bilingual education. Using large household data sets from poor rural communities in Mexico, we find that parental language (failure to speak Spanish) represents an important barrier to the schooling of indigenous children. We provide an empirical test suggesting that this largely reflects parental human capital related to culture/language, rather than unobserved wealth effects. ...

  16. Economic alternatives for containment barriers

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, P.J.; Jasperse, B.H.; Fisher, M.J. [Geo-Con, Inc., Monroeville, PA (United States)

    1997-12-31

    Fixation, barriers, and containment of existing landfills and other disposal areas are often performed by insitu auger type soil mixing and jet grouting. Cement or other chemical reagents are mixed with soil to form both vertical and horizontal barriers. Immobilization of contaminants can be economically achieved by mixing soil and the contaminants with reagents that solidify or stabilize the contaminated area. Developed in Japan, and relatively new to the United States, the first large scale application was for a vertical barrier at the Jackson Lake Dam project in 1986. This technology has grown in both the civil and environmental field since. The paper describes current United States practice for Deep Soil Mixing (over 12 meters in depth), and Shallow Soil Mixing for vertical barriers and stabilization/solidification, and Jet Grouting for horizontal and vertical barriers. Creating very low permeability barriers at depth with minimal surface return often makes these techniques economical when compared to slurry trenches. The paper will discuss equipment, materials, soil and strength parameters, and quality control.

  17. Filaggrin and Skin Barrier Function.

    Science.gov (United States)

    Kezic, Sanja; Jakasa, Ivone

    2016-01-01

    The skin barrier function is greatly dependent on the structure and composition of the uppermost layer of the epidermis, the stratum corneum (SC), which is made up of flattened anucleated cells surrounded by highly organized and continuous lipid matrix. The interior of the corneocytes consists mainly of keratin filaments aggregated by filaggrin (FLG) protein. Next, together with several other proteins, FLG is cross-linked into a mechanically robust cornified cell envelope providing a scaffold for the extracellular lipid matrix. In addition to its role for the SC structural and mechanical integrity, FLG degradation products account in part for the water-holding capacity and maintenance of acidic pH of the SC, both crucial for the epidermal barrier homoeostasis by regulating activity of multiple enzymes that control desquamation, lipid synthesis and inflammation. The major determinant of FLG expression in the skin are loss-of-function mutations in FLG, the strongest genetic risk factor for atopic dermatitis (AD), an inflammatory skin disease characterized by a reduced skin barrier function. The prevalence of FLG mutations varies greatly among different populations and ranges from about 10% in Northern Europeans to less than 1% in the African populations. An impaired skin barrier facilitates absorption of potentially hazardous chemicals, which might cause adverse effects in the skin, such as contact dermatitis, or systemic toxicity after their passage into blood. In another direction, a leaky epidermal barrier will lead to enhanced loss of water from the skin. A recent study has shown that even subtle increase in epidermal water loss in newborns increases the risk for AD. Although there are multiple modes of action by which FLG might affect skin barrier it is still unclear whether and how FLG deficiency leads to the reduced skin barrier function. This chapter summarizes the current knowledge in this field obtained from clinical studies, and animal and in vitro models

  18. Diabetes and diet: Managing dietary barriers.

    NARCIS (Netherlands)

    Friele, R.D.

    1989-01-01

    This thesis reports on the barriers diabetic patients experience with their diet, and the ways they cope with these barriers. A dietary barrier is a hinderance to a person's well-being, induced by being advised a diet. First inventories were made of possible dietary barriers and ways of coping with

  19. Cytokines and the Skin Barrier

    Directory of Open Access Journals (Sweden)

    Jens Malte Baron

    2013-03-01

    Full Text Available The skin is the largest organ of the human body and builds a barrier to protect us from the harmful environment and also from unregulated loss of water. Keratinocytes form the skin barrier by undergoing a highly complex differentiation process that involves changing their morphology and structural integrity, a process referred to as cornification. Alterations in the epidermal cornification process affect the formation of the skin barrier. Typically, this results in a disturbed barrier, which allows the entry of substances into the skin that are immunologically reactive. This contributes to and promotes inflammatory processes in the skin but also affects other organs. In many common skin diseases, including atopic dermatitis and psoriasis, a defect in the formation of the skin barrier is observed. In these diseases the cytokine composition within the skin is different compared to normal human skin. This is the result of resident skin cells that produce cytokines, but also because additional immune cells are recruited. Many of the cytokines found in defective skin are able to influence various processes of differentiation and cornification. Here we summarize the current knowledge on cytokines and their functions in healthy skin and their contributions to inflammatory skin diseases.

  20. Cylindrical air flow reversal barrier

    Energy Technology Data Exchange (ETDEWEB)

    Woznica, C.; Rodziewicz, M.

    1988-06-01

    Describes an innovative design introduced in the ZMP mine in Zory for quick reversal of ventilation air flow. Geologic mining conditions at the 705 m deep horizon, where the barrier was built, are described. According to the design used until now, a reversal system consisted of safety barriers, ventilation air locks, a ventilation bridge and stopping needed in case of a fire when air flow direction must be reversed. Nine air locks and an expensive concrete ventilation bridge were needed and the air locks had to be operated at 8 points of the region to effect reversal. The new design consists of a 2-storey cylindrical barrier which also fulfills the function of a ventilation bridge. It can be manually or remotely operated by a mechanical or pneumatic system. Tests showed that the new barrier permits immediate air flow reversal while retaining 60% of the original air, which is important in the case of fire and methane hazards. It permits improved seam panelling and splitting of pillars and brings an economy of about 40 million zlotys in construction cost. Design and operation of the barrier is illustrated and ventilation air circulation is explained. 7 figs.

  1. Structure information from fusion barriers

    Indian Academy of Sciences (India)

    S V S Sastry; S Santra

    2000-06-01

    It is shown that the analysis of fusion barrier distributions is not always an unambiguous test or a ‘fingerprint’ of the structure information of the colliding nuclei. Examples are presented with same fusion barrier distributions for nuclei having different structures. The fusion excitation functions for 16O+208Pb, using the coupled reaction channel (CRC) method and correct structure information, have been analysed. The barrier distributions derived from these excitation functions including many of the significant channels are featureless, although these channels have considerable effects on the fusion excitation function. However, a simultaneous analysis of the fusion, elastic and quasi-elastic channels would fix the structure and the reaction unambiguously

  2. Skin Barrier Function and Allergens

    DEFF Research Database (Denmark)

    Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

    2016-01-01

    The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...... and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due......) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen...

  3. Sound propagation over curved barriers

    Science.gov (United States)

    Pierce, Allan D.; Main, Geoffrey L.; Kearns, James A.; Hsieh, H.-A.

    1986-01-01

    Wide barriers with curved tops are studied with emphasis placed on circumstances whereby the local radius of curvature R of the barrier is continuous along the surface and is large compared to a wavelength. Results analogous to those given by Hayek et al. (1978) are reviewed and extended to cases where the radius of curvature and the surface impedance may vary with position. Circumstances not easily interpreted within the framework of the model proposed by Keller (1956) and Hayek et al. are also considered.

  4. The Solution to Green Barrier

    Institute of Scientific and Technical Information of China (English)

    Cui Yan

    2009-01-01

    @@ The recovery process of world economy is rough and full of twists and turns.Especially the trade protectionism,having reemerged under the mask of"green barrier",is making a great impact on the slowly recovering world economy and trade.Then,what are the characteristics of trade barriers in the post-crisis era?Where is the outlet of Chinese manufacturing industry?With these questions,ourreporter interviewed Professor Zhou Shijian,Standing Director to China Association of International Trade and Senior Researcher to SINO-US Relationship Research Centre of Tsinghua University.

  5. Shock Control Bump Optimization for Drag Reduction Using Parallel Efficient Global Optimization Algorithm%基于并行EGO算法的激波控制鼓包减阻优化

    Institute of Scientific and Technical Information of China (English)

    邓枫; 覃宁; 伍贻兆

    2013-01-01

    建立了并行EGO全局优化算法框架,并将其应用于二维和三维激波控制鼓包减阻优化设计当中.EGO全局优化算法是一类基于克里金(Kriging)代理模型的全局优化算法,具有自动平衡全局搜索与局部搜索的优点,适合于处理具有少量设计参数但是函数计算耗时很长的优化问题,例如基于计算流体力学的气动优化设计.为考察并行EGO全局优化算法的效率,选用了4个解析优化算例以及二维和三维激波控制鼓包减阻优化问题对克里金信任法、常数取代法以及罚点法等3种启发式并行策略进行了比较.数值实验表明,并行EGO全局优化算法每次取点个数可多达16个之多,加速将近16倍,其中在3种并行策略中又以罚点法效率最高,因而在计算耗时很长的气动外形优化问题当中具有很大的应用前景.%The parallel efficient global optimization (EGO) algorithm is applied to the 2-D/3-D shock control bump optimizations.The EGO algorithm is a global optimization method based on the Kriging model,which is especially designed for expensive black box functions,such as high-fidelity aerodynamic shape optimizations.Three heuristic parallel strategies including "Kriging believer","constant liar" and " imputed point" strategies are investigated based on four benchmark optimization problems and two shock control bump optimization problems.In shock control bump optimization problems,the parallel EGO algorithm is nearly 16 times faster than the serial EGO algorithm.And our research also shows that' Imputed point' strategy is the best strategy in these optimization problems.

  6. Systems study on engineered barriers: barrier performance analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stula, R.T.; Albert, T.E.; Kirstein, B.E.; Lester, D.H.

    1980-09-01

    A performance assessment model for multiple barrier packages containing unreprocessed spent fuel has been modified and applied to several package designs. The objective of the study was to develop information to be used in programmatic decision making concerning engineered barrier package design and development. The assessment model, BARIER, was developed in previous tasks of the System Study on Engineered Barriers (SSEB). The new version discussed in this report contains a refined and expanded corrosion rate data base which includes pitting, crack growth, and graphitization as well as bulk corrosion. Corrosion rates for oxic and anoxic conditions at each of the two temperature ranges are supplied. Other improvements include a rigorous treatment of radionuclide release after package failure which includes resistance of damaged barriers and backfill, refined temperature calculations that account for convection and radiation, a subroutine to calculate nuclear gamma radiation field at each barrier surface, refined stress calculations with reduced conservatism and various coding improvements to improve running time and core usage. This report also contains discussion of alternative scenarios to the assumed flooded repository as well as the impact of water exclusion backfills. The model was used to assess post repository closure performance for several designs which were all variation of basic designs from the Spent Unreprocessed Fuel (SURF) program. Many designs were found to delay the onset of leaching by at least a few hundreds of years in all geologic media. Long delay times for radionuclide release were found for packages with a few inches of sorption backfill. Release of uranium, plutonium, and americium was assessed.

  7. Plastic Schottky barrier solar cells

    Science.gov (United States)

    Waldrop, James R.; Cohen, Marshall J.

    1984-01-24

    A photovoltaic cell structure is fabricated from an active medium including an undoped, intrinsically p-type organic semiconductor comprising polyacetylene. When a film of such material is in rectifying contact with a magnesium electrode, a Schottky-barrier junction is obtained within the body of the cell structure. Also, a gold overlayer passivates the magnesium layer on the undoped polyacetylene film.

  8. Seasonal breaching of coastal barriers

    NARCIS (Netherlands)

    Tuan, Thieu Quang

    2007-01-01

    Natural or unintended breaching can be catastrophic, causing loss of human lives and damage to infrastructures, buildings and natural habitats. Quantitative understand-ing of coastal barrier breaching is therefore of great importance to vulnerability as-sessment of protection works as well as to

  9. Functional barriers: Properties and evaluation

    NARCIS (Netherlands)

    Feigenbaum, A.; Dole, P.; Aucejo, S.; Dainelli, D.; Cruz Garcia, C. de la; Hankemeier, T.; N'Gono, Y.; Papaspyrides, C.D.; Paseiro, P.; Pastorelli, S.; Pavlidou, S.; Pennarun, P.Y.; Saillard, P.; Vidal, L.; Vitrac, O.; Voulzatis, Y.

    2005-01-01

    Functional barriers are multilayer structures deemed to prevent migration of some chemicals released by food-contact materials into food. In the area of plastics packaging, different migration behaviours of mono- and multilayer structures are assessed in terms of lag time and of their influence of t

  10. Communication Barriers in Distance Education

    Science.gov (United States)

    Isman, Aytekin; Dabaj, Fahme; Altinay, Fahriye; Altinay, Zehra

    2003-01-01

    Communication is a key concept as being the major tool for people in order to satisfy their needs. It is an activity which refers as process and effective communication requires qualified communication with the elimination of communication barriers. As it is known, distance education is a new trend by following contemporary facilities and tools…

  11. FX barriers with smile dynamics

    NARCIS (Netherlands)

    Baker, Glyn; Beneder, Reimer; Zilber, Alex

    2004-01-01

    Our mandate in this work has been to isolate the features of smile consistent models that are most relevant to the pricing of barrier options. We consider the two classical approaches of stochastic and (parametric) local volatility. Although neither has been particularly successful in practice their

  12. Planar doped barrier subharmonic mixers

    Science.gov (United States)

    Lee, T. H.; East, J. R.; Haddad, G. I.

    1992-01-01

    The Planar Doped Barrier (PDB) diode is a device consisting of a p(+) doping spike between two intrinsic layers and n(+) ohmic contacts. This device has the advantages of controllable barrier height, diode capacitance and forward to reverse current ratio. A symmetrically designed PDB has an anti-symmetric current vs. voltage characteristic and is ideal for use as millimeter wave subharmonic mixers. We have fabricated such devices with barrier heights of 0.3, 0.5 and 0.7 volts from GaAs and InGaAs using a multijunction honeycomb structure with junction diameters between one and ten microns. Initial RF measurements are encouraging. The 0.7 volt barrier height 4 micron GaAs devices were tested as subharmonic mixers at 202 GHz with an IF frequency of 1 GHz and had 18 dB of conversion loss. The estimated mismatch loss was 7 dB and was due to higher diode capacitance. The LO frequency was 100.5 GHz and the pump power was 8 mW.

  13. Barrier/Cu contact resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Reid, J.S.; Nicolet, M.A. [California Inst. of Tech., Pasadena, CA (United States); Angyal, M.S.; Lilienfeld, D.; Shacham-Diamand, Y. [Cornell Univ., Ithaca, NY (United States); Smith, P.M. [Sandia National Labs., Albuquerque, NM (United States)

    1995-10-17

    The specific contact resistivity of Cu with ({alpha} + {beta})-Ta, TiN, {alpha}-W, and amorphous-Ta{sub 36}Si{sub 14}N{sub 50} barrier films is measured using a novel four-point-probe approach. Geometrically, the test structures consist of colinear sets of W-plugs to act as current and voltage probes that contact the bottom of a planar Cu/barrier/Cu stack. Underlying Al interconnects link the plugs to the current source and voltmeter. The center-to-center distance of the probes ranges from 3 to 200 {micro}m. Using a relation developed by Vu et al., a contact resistivity of roughly 7 {times} 10{sup {minus}9} {Omega} cm{sup 2} is obtained for all tested barrier/Cu combinations. By reflective-mode small-angle X-ray scattering, the similarity in contact resistivity among the barrier films may be related to interfacial impurities absorbed from the deposition process.

  14. Dynamic characteristics analysis of bump foil journal bearings with air lubrication%气体润滑弹性波箔片轴承动态特性分析

    Institute of Scientific and Technical Information of China (English)

    许怀锦; 刘占生; 吕伟剑; 李华峰

    2011-01-01

    Differential equations of air film in elastic bump foil journal bearing were deducted by the perturbation method with air lubrication Reynolds equation and series expansions of air film, air film thickness and foil deformation.The mathematics model of the relations among air film thickness, bump foil deformation and air film pressure was developed in consideration of air compressibility.Both finite difference method and Newton-Raphson method were applied to solve the coupled differential equations and air film thickness mathematics model equations, while the variation rules of air film stiffness and damping coefficients were achieved with different eccentricities, speeds, perturbation frequencies and different length-diameter ratios.This provides a basis for bump foil journal bearing design,optimization and theoretical and test analysis of rotor-elastic foil bearing system.The numerical results show that the main air film stiffness is enhanced when eccentricity and speed increase, and the value of air film stiffness and damping of bump foil journal bearing are connected strongly with the perturbation frequencies.%通过摄动方法并结合气体润滑压力控制Reynolds方程和气膜压力、气膜厚度及箔片变形等变量的Taylor展开式,推导出弹性波箔片轴承气膜动力特性系数计算微分方程组.同时,考虑气体可压缩性等因素,建立气膜厚度、箔片变形和气膜压力三者之间关系的数学模型方程组.运用Newton-Raphson迭代法和有限差分法耦合求解气膜动力特性系数计算微分方程组和气膜厚度数学模型方程组,得到弹性波箔片轴承气膜刚度和阻尼等动力特性系数随偏心率、转速、扰动频率及轴承长径比等参数变化的规律特性,为箔片轴承设计、优化和弹性波箔片轴承-转子系统理论及试验分析奠定基础.计算结果表明,随着偏心率和转速的增大,润滑气膜主刚度均有不同程度的提高,同时,润滑气膜刚

  15. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the ``barriers`` literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  16. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the barriers'' literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  17. Patient advocacy: barriers and facilitators

    Directory of Open Access Journals (Sweden)

    Nikravesh Mansoure

    2006-03-01

    Full Text Available Abstract Background During the two recent decades, advocacy has been a topic of much debate in the nursing profession. Although advocacy has embraced a crucial role for nurses, its extent is often limited in practice. While a variety of studies have been generated all over the world, barriers and facilitators in the patient advocacy have not been completely identified. This article presents the findings of a study exploring the barriers and facilitators influencing the role of advocacy among Iranian nurses. Method This study was conducted by grounded theory method. Participants were 24 Iranian registered nurses working in a large university hospital in Tehran, Iran. Semi-structured interviews were used for data collection. All interviews were transcribed verbatim and simultaneously Constant comparative analysis was used according to the Strauss and Corbin method. Results Through data analysis, several main themes emerged to describe the factors that hindered or facilitated patient advocacy. Nurses in this study identified powerlessness, lack of support, law, code of ethics and motivation, limited communication, physicians leading, risk of advocacy, royalty to peers, and insufficient time to interact with patients and families as barriers to advocacy. As for factors that facilitated nurses to act as a patient advocate, it was found that the nature of nurse-patient relationship, recognizing patients' needs, nurses' responsibility, physician as a colleague, and nurses' knowledge and skills could be influential in adopting the advocacy role. Conclusion Participants believed that in this context taking an advocacy role is difficult for nurses due to the barriers mentioned. Therefore, they make decisions and act as a patient's advocate in any situation concerning patient needs and status of barriers and facilitators. In most cases, they can not act at an optimal level; instead they accept only what they can do, which we called 'limited advocacy' in

  18. Dielectric barrier discharges applied for optical spectrometry

    Science.gov (United States)

    Brandt, S.; Schütz, A.; Klute, F. D.; Kratzer, J.; Franzke, J.

    2016-09-01

    The present review reflects the importance of dielectric barrier discharges for optical spectrometric detection in analytical chemistry. In contrast to usual discharges with a direct current the electrodes are separated by at least one dielectric barrier. There are two main features of the dielectric barrier discharges: they can serve as dissociation and excitation devices as well as ionization sources, respectively. This article portrays various application fields of dielectric barrier discharges in analytical chemistry used for elemental and molecular detection with optical spectrometry.

  19. Penetration through the Skin Barrier

    DEFF Research Database (Denmark)

    Nielsen, Jesper Bo; Benfeldt, Eva; Holmgaard, Rikke

    2016-01-01

    . During recent decades, the latter has received increased attention as a route for intentionally delivering drugs to patients. This has stimulated research in methods for sampling, measuring and predicting percutaneous penetration. Previous chapters have described how different endogenous, genetic...... and exogenous factors may affect barrier characteristics. The present chapter introduces the theory for barrier penetration (Fick's law), and describes and discusses different methods for measuring the kinetics of percutaneous penetration of chemicals, including in vitro methods (static and flow......-through diffusion cells) as well as in vivo methods (microdialysis and microperfusion). Then follows a discussion with examples of how different characteristics of the skin (age, site and integrity) and of the penetrants (size, solubility, ionization, logPow and vehicles) affect the kinetics of percutaneous...

  20. Security barriers with automated reconnaissance

    Science.gov (United States)

    McLaughlin, James O; Baird, Adam D; Tullis, Barclay J; Nolte, Roger Allen

    2015-04-07

    An intrusion delaying barrier includes primary and secondary physical structures and can be instrumented with multiple sensors incorporated into an electronic monitoring and alarm system. Such an instrumented intrusion delaying barrier may be used as a perimeter intrusion defense and assessment system (PIDAS). Problems with not providing effective delay to breaches by intentional intruders and/or terrorists who would otherwise evade detection are solved by attaching the secondary structures to the primary structure, and attaching at least some of the sensors to the secondary structures. By having multiple sensors of various types physically interconnected serves to enable sensors on different parts of the overall structure to respond to common disturbances and thereby provide effective corroboration that a disturbance is not merely a nuisance or false alarm. Use of a machine learning network such as a neural network exploits such corroboration.

  1. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  2. Barrierer for realisering af energibesparelser i bygninger

    DEFF Research Database (Denmark)

    Jensen, Ole Michael

    2004-01-01

    For få bygningsejere går i gang med at investere i energibesparelser. Årsagen tilskrives en række barrierer, som møder den enkelte bygningsejer, når denne vil i gang med at foretage energirenoveringer. Men ikke alle barrierer handler om barrierer i traditionel forstand, men om tilbageholdenhed. Den...

  3. Market barriers to welfare product innovations

    NARCIS (Netherlands)

    Binnekamp, M.H.A.; Ingenbleek, P.T.M.

    2006-01-01

    New products that are based on higher animal welfare standards encounter several barriers on the road to market acceptance. The authors focus on the Dutch poultry sector and distinguish between retailer and consumer barriers. Retailer barriers include the powerful position of retailers, the price co

  4. Design of the Muong Chuoi Barrier

    NARCIS (Netherlands)

    Van Vliegen, K.; Van Oorschot, N.; Meinen, N.; Van Dijk, S.; Reimert, Z.

    2013-01-01

    Ho Chi Minh City has to deal with severe flooding in the rainy season. To prevent the city from this flooding, MARD set up plan 1547. The main idea of the plan is to build a ring dike around HCMC in combination with several movable tidal barriers. One of these barriers is the Muong Chuoi Barrier. I

  5. Barriers to Mammography among Inadequately Screened Women

    Science.gov (United States)

    Stoll, Carolyn R. T.; Roberts, Summer; Cheng, Meng-Ru; Crayton, Eloise V.; Jackson, Sherrill; Politi, Mary C.

    2015-01-01

    Mammography use has increased over the past 20 years, yet more than 30% of women remain inadequately screened. Structural barriers can deter individuals from screening, however, cognitive, emotional, and communication barriers may also prevent mammography use. This study sought to identify the impact of number and type of barriers on mammography…

  6. Market barriers to welfare product innovations

    NARCIS (Netherlands)

    Binnekamp, M.H.A.; Ingenbleek, P.T.M.

    2006-01-01

    New products that are based on higher animal welfare standards encounter several barriers on the road to market acceptance. The authors focus on the Dutch poultry sector and distinguish between retailer and consumer barriers. Retailer barriers include the powerful position of retailers, the price

  7. Flexible pile thermal barrier insulator

    Science.gov (United States)

    Anderson, G. E.; Fell, D. M.; Tesinsky, J. S. (Inventor)

    1978-01-01

    A flexible pile thermal barrier insulator included a plurality of upstanding pile yarns. A generally planar backing section supported the upstanding pile yarns. The backing section included a plurality of filler yarns forming a mesh in a first direction. A plurality of warp yarns were looped around said filler yarns and pile yarns in the backing section and formed a mesh in a second direction. A binder prevented separation of the yarns in the backing section.

  8. Overcome barriers to career success

    Energy Technology Data Exchange (ETDEWEB)

    Raudsepp, E.

    1983-04-01

    A test is given to determine if an engineer suffers from one of the three barriers to technical success: fear of success, fear of failure, or perfectionism. As in most such tests, the middle way is best. Successful engineers know that perfection cannot be attained, that they don't have time to worry about failure or success, and that by aiming and perservering in doing things well, success can be achieved.

  9. Removing Barriers to Interdisciplinary Research

    CERN Document Server

    Jacobs, Naomi

    2010-01-01

    A significant amount of high-impact contemporary scientific research occurs where biology, computer science, engineering and chemistry converge. Although programmes have been put in place to support such work, the complex dynamics of interdisciplinarity are still poorly understood. In this paper we interrogate the nature of interdisciplinary research and how we might measure its "success", identify potential barriers to its implementation, and suggest possible mechanisms for removing these impediments.

  10. Wet Work and Barrier Function.

    Science.gov (United States)

    Fartasch, Manigé

    2016-01-01

    Wet work defined as unprotected exposure to humid environments/water; high frequencies of hand washing procedures or prolonged glove occlusion is believed to cause irritant contact dermatitis in a variety of occupations. This review considers the recent studies on wet-work exposure and focuses on its influence on barrier function. There are different methods to study the effect of wet work on barrier function. On the one hand, occupational cohorts at risk can be monitored prospectively by skin bioengineering technology and clinical visual scoring systems; on the other hand, experimental test procedures with defined application of water, occlusion and detergents are performed in healthy volunteers. Both epidemiological studies and the results of experimental procedures are compared and discussed. A variety of epidemiological studies analyze occupational cohorts at risk. The measurement of transepidermal water loss, an indicator of the integrity of the epidermal barrier, and clinical inspection of the skin have shown that especially the frequencies of hand washing and water contact/contact to aqueous mixtures seem to be the main factors for the occurrence of barrier alterations. On the other hand, in a single cross-sectional study, prolonged glove wearing (e.g. occlusion for 6 h per shift in clean-room workers) without exposure to additional hazardous substances seemed not to affect the skin negatively. But regarding the effect of occlusion, there is experimental evidence that previously occluded skin challenged with sodium lauryl sulfate leads to an increased susceptibility to the irritant with an aggravation of the irritant reaction. These findings might have relevance for the real-life situation in so far as after occupational glove wearing, the skin is more susceptible to potential hazards to the skin even during leisure hours.

  11. Lake Borgne Surge Barrier Study

    Science.gov (United States)

    2010-09-01

    Savant , and Darla C. McVan September 2010 Approved for public release; distribution is unlimited. ERDC/CHL TR-10-10 September 2010 Lake...Borgne Surge Barrier Study S. Keith Martin, Gaurav Savant , and Darla C. McVan Coastal and Hydraulics Laboratory U.S. Army Engineer Research and...conducted by Keith Martin, Dr. Gaurav Savant , and Darla C. McVan. This work was conducted at the Coastal and Hydraulics Laboratory (CHL) of the

  12. Perceived Sodium Reduction Barriers Among Patients with Chronic Kidney Disease: Which Barriers Are Important and Which Patients Experience Barriers?

    Science.gov (United States)

    Meuleman, Yvette; Hoekstra, Tiny; Dekker, Friedo W; van der Boog, Paul J M; van Dijk, Sandra

    2017-09-08

    The purposes of this study were to assess the importance of perceived sodium reduction barriers among patients with chronic kidney disease (CKD) and identify associated sociodemographic, clinical, and psychosocial factors. A total of 156 patients with CKD completed a questionnaire assessing sodium reduction barriers (18 self-formulated items), depressive symptoms (Beck Depression Inventory), perceived autonomy support (Modified Health Care Climate Questionnaire), and self-efficacy (Partners in Health Questionnaire). Factor analysis was used to identify barrier domains. Correlation coefficients were computed to examine relationships between barrier domains and patient characteristics. Nine barrier domains were identified. Barriers perceived as important were as follows: high sodium content in products, lack of sodium feedback, lack of goal setting and discussing strategies for sodium reduction, and not experiencing CKD-related symptoms (mean scores > 3.0 on 5-point scales, ranging from 1 'no barrier' to 5 'very important barrier'). Other barriers (knowledge, attitude, coping skills when eating out, and professional support) were rated as moderately important (rated around midpoint), and the barrier 'intrinsic motivation' was rated as somewhat important (mean score = 1.9). Sodium reduction barrier domains were not associated with gender and kidney function, but were associated with age, level of education, number of comorbidities, perceived autonomy support, depressive symptoms, and self-efficacy (range r = 0.17-0.35). Patients with lower self-efficacy and perceived autonomy support scores experienced most sodium reduction barriers. Patients with CKD experience multiple important sodium reduction barriers and could benefit from support strategies that target various sodium reduction barriers and strengthen beliefs regarding self-efficacy and autonomy support. Additionally, environmental interventions should be implemented to reduce sodium levels in processed

  13. Class barriers to psychotherapy and counselling.

    Science.gov (United States)

    Ollerton, I

    1995-01-01

    This paper focuses on the barriers to the uptake of counselling and psychotherapy from a social class perspective. It begins with a definition of class before discussing particular aspects that inhibit uptake. Barriers focused upon are those regarding travel, costs, child care, appointment times and location of actual therapists. Likewise barriers to the effective outcome, for example cognitive and verbal abilities of clients, are addressed and the way in which these barriers inhibit the referral rate from particular social groups. Finally the self-imposed barriers of certain social groups are explored regarding self exile from the counselling arena.

  14. Diffraction of sound by nearly rigid barriers

    Science.gov (United States)

    Hadden, W. J., Jr.; Pierce, A. D.

    1976-01-01

    The diffraction of sound by barriers with surfaces of large, but finite, acoustic impedance was analyzed. Idealized source-barrier-receiver configurations in which the barriers may be considered as semi-infinite wedges are discussed. Particular attention is given to situations in which the source and receiver are at large distances from the tip of the wedge. The expression for the acoustic pressure in this limiting case is compared with the results of Pierce's analysis of diffraction by a rigid wedge. An expression for the insertion loss of a finite impedance barrier is compared with insertion loss formulas which are used extensively in selecting or designing barriers for noise control.

  15. Mathematical modeling of complex noise barriers

    Energy Technology Data Exchange (ETDEWEB)

    Hayek, S.I.

    1982-01-01

    Mathematical modeling of the noise reduction efficiency of highway noise barriers depends on the shape and absorptivity of the barrier, the influence of the impedance of the ground under the receiver, the atmospheric conditions as well as traffic details. The mathematical model for a barrier's noise reduction requires the knowledge of point-to-point acoustic diffraction models. In many instances, the shape of the barrier is simple; such as thin wall (edge), sharp wedge, and cylindrically topped berms. However, new designs of more efficient barriers have been investigated recently.

  16. Study on Mine Pressure Bumping Prevention and Control of Slice Mining in Ultra Thick Steep Inclined Seam of Deep Mine%深部急倾斜特厚煤层分层开采冲击地压防治技术

    Institute of Scientific and Technical Information of China (English)

    于贵良; 李前; 王元杰

    2011-01-01

    为了防治砚北煤矿1502采区急倾斜特厚煤层水平分段开采的冲击地压.对该矿冲击地压发生的影响因素及实测数据进行了分析研究,得出运输巷冲击地压的发生主要受上下分层工作面采掘交替影响,在上部回采工作面超前下部掘进工作面80~150 m时影响最为明显;回风巷除受采掘交替影响外,还受地质构造应力的影响,在煤层倾角突变处的前方100-150 m影响显著.采用钻屑法、电磁辐射法、微震法和地音法对冲击地压实施预测预报;并采取切顶爆破、煤体爆破对顶板及煤体进行卸压措施,掘进工作面冲击地压次数降低了44.4%,回采工作面降低了66.6%,保障了砚北煤矿强冲击地压工作面的安全生产.%In order to prevent and control of the mine pressure bumping of the horizontal slice mining in the steep inclined and ultra thick seam in No.1502 mining block in Yanbei Mine, the paper had an analysis and study on the influence factors of the mine pressure bumping occurred and the site measured data.The analysis and study showed that the mine pressure bumping occurred in the transportation gateway would mainly be affected by the mining and excavation alternative influences of the mining faces in the top and low slice seam.When the top slice coal mining face was 80 ~ 150 m advanced of the low slice gateway driving face, the influence of the mine pressure bumping would be more obvious.Except for the mining and excavation alternative inferences, the air returning gateway would be also affected by the geological structure stress and at 100-150 m in front of the seam angle varied, the influence of the mine pressure bumping would be obvious.The drilling cuttings method, the electromagnetic radiation method, the micro seismic method and acoustic emission method were applied to predict and pre-warn the mine pressure bumping.The roof cut blasting and the seam blasting were applied to release the pressure of the roof and

  17. Avoiding barriers in control of mowing robot

    Institute of Scientific and Technical Information of China (English)

    QIU Bai-jing; QIAN Guo-hong; XIANG Zhong-ping; LI Zuo-peng

    2006-01-01

    Due to complicated barriers,it is difficult to track the path of the mowing robot and to avoid barriers.In order to solve the problem,a method based on distance-measuring sensors and fuzzy control inputs was proposed.Its track was composed of beelines and was easy to tail.The fuzzy control inputs were based on the front barrier distance and the difference between the left and right barrier distance measured by ultrasonic sensors;the output was the direction angle.The infrared sensors around the robot improved its safety in avoiding barriers.The result of the method was feasible,agile,and stable.The distance between the robot and the barriers could be changed by altering the inputs and outputs of fuzzy control and the length of the beelines.The disposed sensors can fulfill the need of the robot in avoiding barriers.

  18. Dielectric barrier discharges in analytical chemistry.

    Science.gov (United States)

    Meyer, C; Müller, S; Gurevich, E L; Franzke, J

    2011-06-21

    The present review reflects the importance of dielectric barrier discharges in analytical chemistry. Special about this discharge is-and in contrast to usual discharges with direct current-that the plasma is separated from one or two electrodes by a dielectric barrier. This gives rise to two main features of the dielectric barrier discharges; it can serve as dissociation and excitation device and as ionization mechanism, respectively. The article portrays the various application fields for dielectric barrier discharges in analytical chemistry, for example the use for elemental detection with optical spectrometry or as ionization source for mass spectrometry. Besides the introduction of different kinds of dielectric barrier discharges used for analytical chemistry from the literature, a clear and concise classification of dielectric barrier discharges into capacitively coupled discharges is provided followed by an overview about the characteristics of a dielectric barrier discharge concerning discharge properties and the ignition mechanism.

  19. Mixing processes during the evolution of red giants with moderate metal deficiencies the role of molecular-weight barriers

    CERN Document Server

    Charbonnel, C; Wallerstein, G; Charbonnel, Corinne; Brown, Jeffery A.; Wallerstein, George

    1997-01-01

    We have assembled accurate abundance data for Li, C, and N as well as the 12C/13C ratio for five field giants with [Fe/H]=-0.6 including Arcturus and two stars in the globular cluster 47 Tuc. Using their very precise Mbol values obtained from HIPPARCOSparallaxes, we can place them into an evolutionary sequence. The sequence shows that the 12C/13C ratios ratios drops from 20 to near 7 between Mbol=+1 and +0.5, while Li disappears. At the same time the 12C/14N ratio diminishes by 0.2 to 0.4 dex. The two stars in 47 Tuc with Mbol near -2.0 show even lower 12C14N ratios by 0.4 dex indicating further mixing as they evolved to the top of the red giant branch. These observations confirm the existence of an extra-mixing process that becomes efficient on the red giant branch only when the low-mass stars reach the so-called luminosity function bump. We use the values of the carbon isotopic ratio observed in our sample to get constraints on the mu-barriers that may shield the central regions of a star from extra-mixing....

  20. Tunneling without barriers with gravity

    CERN Document Server

    Kanno, Sugumi; Soda, Jiro

    2012-01-01

    We consider the vacuum decay of the flat Minkowski space to an anti-de Sitter space. We find a one-parameter family of potentials that allow exact, analytical instanton solutions describing tunneling without barriers in the presence of gravity. In the absence of gravity such instantons were found and discussed by Lee and Weinberg more than a quarter of a century ago. The bounce action is also analytically computed. We discuss possible implications of these new instantons to cosmology in the context of the string theory landscape.

  1. 柱形铜凸点在热力耦合场中的原子迁移%Atomic migration of Cu-pillar bumps in thermomechanical coupling fields

    Institute of Scientific and Technical Information of China (English)

    何俐萍; 邬博义; 李艳; 张道姝; 黄洪钟

    2011-01-01

    With further miniaturization and harsh service loading,the failure problems of atomic migration for solder joints become more dominative in integrated circuit(IC) packaging.The temperature difference caused by thermal properties and electrical resistivity among different materials is a vital factor for IC package solder joints.In consideration of such a new lip-chip interconnect form as a Cu-pillar bump,thermo-migration and stress-migration of Cu-pillar bumps in thermomechanical coupling fields were investigated via the kinetic theory and viscoplastic mechanical analysis by means of finite element method.Informed of influencing factors of atomic migration,we obtained such parameters as temperature gradient and stress distribution in a specific model under temperature load,and then concluded the failure mechanism and occurrence conditions of atomic migration in multi-field coupling.The established failure models of atomic migration in the paper are expected to help improving the reliability in IC packaging.%随着尺寸的进一步微型化和载荷严酷化,集成电路(integrated circuit,IC)封装焊点中的原子迁移失效问题越来越突出。由于材料热性能和电阻率的差异而造成的温差是封装焊点所要面对的主要问题之一。针对铜柱形凸点这种新型倒装芯片互连形式,通过热动力学理论和黏塑性力学分析,运用有限元方法研究了热场和力场耦合作用下柱形铜凸点的热迁移和应力迁移现象。通过分析温度载荷模型下影响原子迁移的多个因素,提取了温度梯度和应力分布等关键参数,进而得到热力耦合场作用下原子迁移的失效机制和发生条件。所建立的失效模型有助于促进IC封装方面原子迁移的可靠性改善工作。

  2. Westinghouse thermal barrier coatings development

    Energy Technology Data Exchange (ETDEWEB)

    Goedjen, J.G.; Wagner, G. [Westinghouse Electric Corp., Orlando, FL (United States)

    1995-10-01

    Westinghouse, in conjunction with the Department of Energy and Oak Ridge National Laboratory, has embarked upon a program for the development of advanced thermal barrier coatings for industrial gas turbines. Development of thermal barrier coatings (TBC`s) for industrial gas turbines has relied heavily on the transfer of technology from the aerospace industry. Significant differences in the time/temperature/stress duty cycles exist between these two coating applications. Coating systems which perform well in aerospace applications may not been optimized to meet power generation performance requirements. This program will focus on development of TBC`s to meet the specific needs of power generation applications. The program is directed at developing a state-of-the-art coating system with a minimum coating life of 25,000 hours at service temperatures required to meet increasing operating efficiency goals. Westinghouse has assembled a team of university and industry leaders to accomplish this goal. Westinghouse will coordinate the efforts of all program participants. Chromalloy Turbine Technologies, Inc. and Sermatech International, Inc. will be responsible for bond coat and TBC deposition technology. Praxair Specialty Powders, Inc. will be responsible for the fabrication of all bond coat and ceramic powders for the program. Southwest Research Institute will head the life prediction modelling effort; they will also be involved in coordinating nondestructive evaluation (NDE) efforts. Process modelling will be provided by the University of Arizona.

  3. PWM Converter Power Density Barriers

    Science.gov (United States)

    Kolar, Johann W.; Drofenik, Uwe; Biela, Juergen; Heldwein, Marcelo; Ertl, Hans; Friedli, Thomas; Round, Simon

    Power density of power electronic converters has roughly doubled every 10 years since 1970. Behind this trajectory is the continuous advancement of power semiconductor devices, which has increased the converter switching frequencies by a factor of 10 every decade. However, today's cooling concepts and passive components are major barriers for a continuation of this trend. To identify such technological barriers, this paper investigates the volume of the cooling system and passive components as a function of the switching frequency for power electronic converters and determines the switching frequency that minimizes the total volume. A power density limit of 28kW/dm3 at 300kHz is calculated for an isolated DC-DC converter, 44kW/dm3 at 820kHz for a three-phase unity power factor PWM rectifier, and 26kW/dm3 at 21kHz for a sparse matrix converter. For single-phase AC-DC conversion a general limit of 35kW/dm3 results from the DC link capacitor. These power density limits highlight the need to broaden the scope of power electronics research to include cooling systems, high frequency electromagnetics, interconnection and packaging technology, and multi-domain modelling and simulation to ensure further advancement along the power density trajectory.

  4. A double barrier memristive device

    Science.gov (United States)

    Hansen, M.; Ziegler, M.; Kolberg, L.; Soni, R.; Dirkmann, S.; Mussenbrock, T.; Kohlstedt, H.

    2015-09-01

    We present a quantum mechanical memristive Nb/Al/Al2O3/NbxOy/Au device which consists of an ultra-thin memristive layer (NbxOy) sandwiched between an Al2O3 tunnel barrier and a Schottky-like contact. A highly uniform current distribution for the LRS (low resistance state) and HRS (high resistance state) for areas ranging between 70 μm2 and 2300 μm2 were obtained, which indicates a non-filamentary based resistive switching mechanism. In a detailed experimental and theoretical analysis we show evidence that resistive switching originates from oxygen diffusion and modifications of the local electronic interface states within the NbxOy layer, which influences the interface properties of the Au (Schottky) contact and of the Al2O3 tunneling barrier, respectively. The presented device might offer several benefits like an intrinsic current compliance, improved retention and no need for an electric forming procedure, which is especially attractive for possible applications in highly dense random access memories or neuromorphic mixed signal circuits.

  5. Overcoming Barriers in Unhealthy Settings

    Directory of Open Access Journals (Sweden)

    Michael K. Lemke

    2016-03-01

    Full Text Available We investigated the phenomenon of sustained health-supportive behaviors among long-haul commercial truck drivers, who belong to an occupational segment with extreme health disparities. With a focus on setting-level factors, this study sought to discover ways in which individuals exhibit resiliency while immersed in endemically obesogenic environments, as well as understand setting-level barriers to engaging in health-supportive behaviors. Using a transcendental phenomenological research design, 12 long-haul truck drivers who met screening criteria were selected using purposeful maximum sampling. Seven broad themes were identified: access to health resources, barriers to health behaviors, recommended alternative settings, constituents of health behavior, motivation for health behaviors, attitude toward health behaviors, and trucking culture. We suggest applying ecological theories of health behavior and settings approaches to improve driver health. We also propose the Integrative and Dynamic Healthy Commercial Driving (IDHCD paradigm, grounded in complexity science, as a new theoretical framework for improving driver health outcomes.

  6. Barriers to medical error reporting

    Directory of Open Access Journals (Sweden)

    Jalal Poorolajal

    2015-01-01

    Full Text Available Background: This study was conducted to explore the prevalence of medical error underreporting and associated barriers. Methods: This cross-sectional study was performed from September to December 2012. Five hospitals, affiliated with Hamadan University of Medical Sciences, in Hamedan,Iran were investigated. A self-administered questionnaire was used for data collection. Participants consisted of physicians, nurses, midwives, residents, interns, and staffs of radiology and laboratory departments. Results: Overall, 50.26% of subjects had committed but not reported medical errors. The main reasons mentioned for underreporting were lack of effective medical error reporting system (60.0%, lack of proper reporting form (51.8%, lack of peer supporting a person who has committed an error (56.0%, and lack of personal attention to the importance of medical errors (62.9%. The rate of committing medical errors was higher in men (71.4%, age of 50-40 years (67.6%, less-experienced personnel (58.7%, educational level of MSc (87.5%, and staff of radiology department (88.9%. Conclusions: This study outlined the main barriers to reporting medical errors and associated factors that may be helpful for healthcare organizations in improving medical error reporting as an essential component for patient safety enhancement.

  7. Barrier experiment: Shock initiation under complex loading

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  8. Identification of Key Barriers in Workforce Development

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-03-31

    This report documents the identification of key barriers in the development of an adequate national security workforce as part of the National Security Preparedness Project, being performed under a Department of Energy/National Nuclear Security Administration grant. Many barriers exist that prevent the development of an adequate number of propertly trained national security personnel. Some barriers can be eliminated in a short-term manner, whereas others will involve a long-term strategy that takes into account public policy.

  9. The biological significance of brain barrier mechanisms

    DEFF Research Database (Denmark)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld

    2016-01-01

    properties. In the blood-brain barrier proper, this is combined with a paucity of vesicular transport that is a characteristic of other vascular beds. Without such a diffusional restrain, the cellular transport mechanisms in the barrier interfaces would be ineffective. Superimposed on these physical....... In addition, such studies, if applied to brain pathologies such as stroke, trauma, or multiple sclerosis, will aid in defining the contribution of brain barrier pathology to these conditions, either causative or secondary....

  10. Barriers for realisation of energy savings in buildings; Barrierer for realisering af energibesparelser i bygninger

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, O.M.

    2004-07-01

    Many years' efforts within the energy labelling area have shown large saving potentials in heating and use of electricity in buildings. At the same time it has been proved that these saving potentials, even when economically advantageous, only are cashed to a limited extent. The reason to this is ascribed to barriers that meet the individual building owner who wants to start saving energy. Most barriers are known and a lot of these have been sought overcome for some time. The questions are how many barriers still exist, have new barriers arisen and the character of these barriers. On this background the objective of this survey has been to concretize and study the barriers, which are blocking reasonable energy savings. Focus has especially been on barriers for realisation of heating savings, but through a general evaluation of energy savings of barriers other forms of energy saving methods have been taken into consideration. Special interest has been directed towards houses, typically one family houses, which are affected by the Energy Labelling Scheme. The concept barriers include all kinds of barriers, also barriers that not are acknowledged as barriers by the individual house owner, or that on closer inspection turn out to be something else than actual barriers. This note suggests an alternative inertia model, in order to create an idea of the inertness characteristic of the many house owners who understand the message but fail to act on it. (BA)

  11. Barriers Approach to Innovation in Academic Libraries

    Directory of Open Access Journals (Sweden)

    Fu-Hsuan Chuang

    2016-11-01

    Full Text Available Innovation in academic libraries is not a brand new issue. Academic libraries can benefit from successful innovation, since innovation is a key contributor to gaining and sustaining competitive advantage for survival. Building on two case studies, 28 participants from leadership teams to practitioners are involved, the qualitative findings identified the specific two types of barriers that academic libraries face by applying a barriers approach to innovation, that’s, environmental and organizational barriers. Especially, seven dimensions of two types of barriers to innovation are found.

  12. Altered permeability barrier structure in cholesteatoma matrix

    DEFF Research Database (Denmark)

    Svane-Knudsen, Viggo; Halkier-Sørensen, Lars; Rasmussen, Gurli

    2002-01-01

    The stratum corneum of the cholesteatoma epithelium comprises the greater part of the cholesteatoma matrix. The permeability barrier that militates against diffusion and penetration of infectious and toxic agents into and through the epithelium is situated here. The multiple long sheets of lamellar...... lipid structures filling the intercellular spaces mainly control the barrier function. The barrier in cholesteatoma epithelium is several times thicker than in unaffected skin but presents distinctive features of a defective barrier as seen in other scaling skin diseases. The intercellular spaces appear...

  13. Beam loss caused by edge focusing of injection bump magnets and its mitigation in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    Science.gov (United States)

    Hotchi, H.; Tani, N.; Watanabe, Y.; Harada, H.; Kato, S.; Okabe, K.; Saha, P. K.; Tamura, F.; Yoshimoto, M.

    2016-01-01

    In the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, transverse injection painting is utilized not only to suppress space-charge induced beam loss in the low energy region but also to mitigate foil scattering beam loss during charge-exchange injection. The space-charge induced beam loss is well minimized by the combination of modest transverse painting and full longitudinal painting. But, for sufficiently mitigating the foil scattering part of beam loss, the transverse painting area has to be further expanded. However, such a wide-ranging transverse painting had not been realized until recently due to beta function beating caused by edge focusing of pulsed injection bump magnets during injection. This beta function beating additionally excites random betatron resonances through a distortion of the lattice superperiodicity, and its resultant deterioration of the betatron motion stability causes significant extra beam loss when expanding the transverse painting area. To solve this issue, we newly installed pulse-type quadrupole correctors to compensate the beta function beating. This paper presents recent experimental results on this correction scheme for suppressing the extra beam loss, while discussing the beam loss and its mitigation mechanisms with the corresponding numerical simulations.

  14. Beam loss caused by edge focusing of injection bump magnets and its mitigation in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    Directory of Open Access Journals (Sweden)

    H. Hotchi

    2016-01-01

    Full Text Available In the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, transverse injection painting is utilized not only to suppress space-charge induced beam loss in the low energy region but also to mitigate foil scattering beam loss during charge-exchange injection. The space-charge induced beam loss is well minimized by the combination of modest transverse painting and full longitudinal painting. But, for sufficiently mitigating the foil scattering part of beam loss, the transverse painting area has to be further expanded. However, such a wide-ranging transverse painting had not been realized until recently due to beta function beating caused by edge focusing of pulsed injection bump magnets during injection. This beta function beating additionally excites random betatron resonances through a distortion of the lattice superperiodicity, and its resultant deterioration of the betatron motion stability causes significant extra beam loss when expanding the transverse painting area. To solve this issue, we newly installed pulse-type quadrupole correctors to compensate the beta function beating. This paper presents recent experimental results on this correction scheme for suppressing the extra beam loss, while discussing the beam loss and its mitigation mechanisms with the corresponding numerical simulations.

  15. Pratt & Whitney thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Bornstein, N. [United Technologies Research Center, East Hartford, CT (United States); Marcin, J. [Pratt & Whitney Aircraft Co., East Hartford, CT (United States)

    1995-10-01

    The objective of the Advanced Turbine Systems (ATS) Program is to develop ultra-high efficient, environmentally superior, and cost competitive gas turbine systems. The operating profiles of these industrial gas turbines are long, less cyclic with fewer transients-compared with those for aircraft gas turbine engines. Therefore, creep rather than thermal fatigue, becomes primary life-limiting for hot section components. Thermal barrier coatings (TBCs) will be used to achieve the objectives of the program. TBCs allow surface temperatures to increase without compromising the structural properties of the alloy. TBCs typically consist of a ceramic insulating layer, deposited onto the substrate with an intervening metallic layer, which imparts oxidation protection to the substrate and provides a surface to which the ceramic layer can adhere.

  16. Crash barrier research in the Netherlands.

    NARCIS (Netherlands)

    Flury, F.C. & Paar, H.G.

    1973-01-01

    Research by the SWOV has led to the development of a series of crash barriers of basically the same design but with varying degrees of resistance to lateral deflection. Requirements to which in general a crash barrier should fulfill are presented.

  17. Barriers to adherence in cystic fibrosis

    DEFF Research Database (Denmark)

    Bregnballe, Vibeke; Schiøtz, Peter Oluf

    2012-01-01

    Danish patients with cystic fibrosis aged 14 to 25 years and their parents. Conclusions: The present study showed that the majority of adolescents with CF and their parents experienced barriers to treatment adherence. Patients and parents agreed that the three most common barriers encountered lack...

  18. Overcoming Blocks and Barriers to Creativity.

    Science.gov (United States)

    Raudsepp, Eugene

    1982-01-01

    Organizational barriers to creativity are examined. It is noted that resistance to change is a major impediment to creative problem solving in most organizations. Understanding the barriers to change that exist is viewed to help people exercise and develop their creativity more fully and effectively. (MP)

  19. Storm impacts on small barrier islands

    DEFF Research Database (Denmark)

    Kroon, Aart; Fruergaard, Mikkel

    The shorelines of the Baltic Sea and the inner coastal waters in Denmark consist of many barrier islands. These sandy barrier islands were mainly formed in the Holocene and are still very dynamic. The present day changes in the morphology are dominantly governed by storm waves and associated high...

  20. Fracture mechanism of a thermal barrier coating

    Science.gov (United States)

    Samoilenko, V. M.; Ravilov, R. G.; Drevnyak, V. V.; Petrova, M. A.

    2016-06-01

    The fracture mechanism of the thermal barrier coating of gas turbine blades is studied. The causes of the fracture of the ceramic layer are discussed and the possible ways to increase the fatigue life of the thermal barrier coating are considered.

  1. Nurses' barriers to learning: an integrative review.

    Science.gov (United States)

    Santos, Marion C

    2012-07-01

    This integrative review of the literature describes nurses' barriers to learning. Five major themes emerged: time constraints, financial constraints, workplace culture, access/relevance, and competency in accessing electronic evidence-based practice literature. The nurse educator must address these barriers for the staff to achieve learning and competency.

  2. Antimicrobial Peptides, Infections and the Skin Barrier

    DEFF Research Database (Denmark)

    Clausen, Maja-Lisa; Agner, Tove

    2016-01-01

    The skin serves as a strong barrier protecting us from invading pathogens and harmful organisms. An important part of this barrier comes from antimicrobial peptides (AMPs), which are small peptides expressed abundantly in the skin. AMPs are produced in the deeper layers of the epidermis...

  3. Mucus as a Barrier to Drug Delivery

    DEFF Research Database (Denmark)

    Bøgh, Marie; Nielsen, Hanne Mørck

    2015-01-01

    Viscoelastic mucus lines all mucosal surfaces of the body and forms a potential barrier to mucosal drug delivery. Mucus is mainly composed of water and mucins; high-molecular weight glycoproteins forming an entangled network. Consequently, mucus forms a steric barrier and due to its negative charge...... and hydrophobic domains, the overall hydrophilic mucus also presents an interactive barrier limiting the free diffusion of components within and through the mucus. Furthermore, mucus is a dynamic barrier due to its continuous secretion and shedding from the mucosal surfaces. Mucus is thus a highly complex gel......, studies of peptide and protein drug diffusion in and through mucus and studies of mucus-penetrating nanoparticles are included to illustrate the mucus as a potentially important barrier to obtain sufficient bioavailability of orally administered drugs, and thus an important parameter to address...

  4. Advancements in subsurface barrier wall technology

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Ash, R.E. IV; Caputi, J.R. [Eckenfelder Inc., Mahwah, NJ (United States)

    1995-12-31

    Subsurface barrier walls have been an important component of site remediation efforts for nearly thirty years. However, until the last decade, limited design options were available for barrier wall construction. Most barrier walls were constructed using traditional technologies such as soil-bentonite slurry trench and, in some instances, conventional compacted clay. While other technologies certainly existed, such as vibrating beam and sheet pile walls, they represented a minor share of the remediation market. Today the remediation engineer considering a subsurface barrier wall-based remediation is confronted with a baffling array, of new technologies and permutations of these technologies. Moreover, new technologies are entering the marketplace seemingly on a monthly basis. A partial listing of available barrier wall technologies is presented.

  5. Barriers to physical activity among working mothers.

    Science.gov (United States)

    Dombrowski, Jill J

    2011-04-01

    Working mothers experience several barriers to physical activity. If these barriers can be identified by occupational health nurses and they can partner with working mothers to reduce these perceived barriers, the health of these workers can be improved and chronic disease risk prevented. The purpose of this study was to measure the effect of self-regulatory efficacy on physical activity among working mothers and to describe specific barriers to physical activity. The Barriers Specific Self-Efficacy Scale (BARSE) and the Kaiser Physical Activity Survey (KPAS) were used to measure the variables. Self-regulatory efficacy was found to be a strong predictor of physical activity in a diverse sample of working mothers who did not meet current recommendations for physical activity. Occupational health nurses can use these findings to design programs for groups and for counseling individuals.

  6. Advanced thermal barrier coating systems

    Science.gov (United States)

    Dorfman, M. R.; Reardon, J. D.

    1985-01-01

    Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer.

  7. Overcoming Biological Barriers with Ultrasound

    Science.gov (United States)

    Thakkar, Dhaval; Gupta, Roohi; Mohan, Praveena; Monson, Kenneth; Rapoport, Natalya

    2011-01-01

    Effect of ultrasound on the permeability of blood vessels and cell membranes to macromolecules and nanodroplets was investigated using mouse carotid arteries and tumor cells. Model macromolecular drug, FITC-dextran with molecular weight of 70,000 Da was used in experiments with carotid arteries. The effect of unfocused 1-MHz ultrasound and and perfluoro-15-crown-5-ether nanodroplets stabilized with the poly(ethylene oxide)-co-poly(D,L-lactide) block copolymer shells was studied. In cell culture experiments, ovarian carcinoma cells and Doxorubicin (DOX) loaded poly(ethylene oxide)-co-polycaprolactone nanodroplets were used. The data showed that the application of ultrasound resulted in permeabilization of all biological barriers tested. Under the action of ultrasound, not only FITC-dextran but also nanodroplets effectively penetrated through the arterial wall; the effect of continuous wave ultrasound was stronger than that of pulsed ultrasound. In cell culture experiments, ultrasound triggered DOX penetration into cell nuclei, presumably due to releasing the drug from the carrier. Detailed mechanisms of the observed effects require further study. PMID:24839333

  8. Transport in the barrier billiard

    Science.gov (United States)

    Saberi Fathi, S. M.; Ettoumi, W.; Courbage, M.

    2016-06-01

    We investigate transport properties of an ensemble of particles moving inside an infinite periodic horizontal planar barrier billiard. A particle moves among bars and elastically reflects on them. The motion is a uniform translation along the bars' axis. When the tangent of the incidence angle, α , is fixed and rational, the second moment of the displacement along the orthogonal axis at time n , , is either bounded or asymptotic to K n2 , when n →∞ . For irrational α , the collision map is ergodic and has a family of weakly mixing observables, the transport is not ballistic, and autocorrelation functions decay only in time average, but may not decay for a family of irrational α 's. An exhaustive numerical computation shows that the transport may be superdiffusive or subdiffusive with various rates or bounded strongly depending on the values of α . The variety of transport behaviors sounds reminiscent of well-known behavior of conservative systems. Considering then an ensemble of particles with nonfixed α , the system is nonergodic and certainly not mixing and has anomalous diffusion with self-similar space-time properties. However, we verified that such a system decomposes into ergodic subdynamics breaking self-similarity.

  9. Engineered barrier environment, Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Wilder, D.G. [Lawrence Livermore National Lab., CA (United States)

    1994-12-31

    The suitability of Yucca Mountain (YM) as a potential nuclear waste repository site will ultimately depend on how well it provides for isolation of the waste. Analysis of isolation capabilities of YM must consider interactions between natural and engineered systems. In addition, environmental conditions are important to EBS design, materials testing, selection, design criteria, and waste-form characterization. Studies of environmental interactions with the EBS, have emphasized processes and changed (not ambient) conditions resulting from interaction with waste, since these are the pertinent conditions for the EBS. The results of these studies indicate that the radioactive heat-of-decay from spent nuclear fuel will play a dominant role in the performance of a potential repository at Yucca Mountain. In addition, coupled hydrothermal-geochemical phenomena may significantly affect the performance of natural barriers surrounding the repository. Depending on the thermal-loading management strategy, as well as site conditions, repository heat may either substantially increase the likelihood of water contacting waste packages, with an associated potential increased magnitude of release and transport of radionuclides, or preclude, or at least minimize, these effects for extended periods of time, perhaps as much as hundreds of thousand years.

  10. The immunological barriers to xenotransplantation.

    Science.gov (United States)

    Vadori, M; Cozzi, E

    2015-10-01

    The availability of cells, tissues and organs from a non-human species such as the pig could, at least in theory, meet the demand of organs necessary for clinical transplantation. At this stage, the important goal of getting over the first year of survival has been reported for both cellular and solid organ xenotransplantation in relevant preclinical primate models. In addition, xenotransplantation is already in the clinic as shown by the broad use of animal-derived medical devices, such as bioprosthetic heart valves and biological materials used for surgical tissue repair. At this stage, however, prior to starting a wide-scale clinical application of xenotransplantation of viable cells and organs, the important obstacle represented by the humoral immune response will need to be overcome. Likewise, the barriers posed by the activation of the innate immune system and coagulative pathway will have to be controlled. As far as xenogeneic nonviable xenografts, increasing evidence suggests that considerable immune reactions, mediated by both innate and adaptive immunity, take place and influence the long-term outcome of xenogeneic materials in patients, possibly precluding the use of bioprosthetic heart valves in young individuals. In this context, the present article provides an overview of current knowledge on the immune processes following xenotransplantation and on the possible therapeutic interventions to overcome the immunological drawbacks involved in xenotransplantation.

  11. Static characterization of bump-type gas foil bearing: intergration of top foil 2-D thick plate model%基于二维厚板模型的波箔片轴承静特性

    Institute of Scientific and Technical Information of China (English)

    刘占生; 徐方程; 张广辉; 曹智选

    2012-01-01

    The 2-D (two-dimensional) thick plate finite element model for top foil was developed. By using coupled finite element mothod and finite difference method, the com- pressible gas lubricated Reynolds equation and the film thickness equation were solved cou- pling together. Predictions of minimum gas film thickness for increasing static loads at two speeds were obtained for bearing mid-plane and edge of bump-type gas foil bearing. The nu- merical results of this finite element model were compared with 1-D (one-dimensional) beam model model, 2-D shin shell model and test data. The results indicate that the minimum film thickness of three models agree well with test data at bearing min-plane, but at bearing edge, the accuracy of 2-D thick plate model is the highest due to its shear effect. 1-D beam model can not reflect film thickness variation along the bearing length direction because it on- ly considers the circumferential direction. The study in this paper established the theoretical foundation of dynamic characteristics research of bump-type gas foil bearing.%建立平箔片的二维厚板有限元模型,运用有限单元法和有限差分法耦合求解Reynolds方程和气膜厚度方程,研究了在两个工作转速下气体波箔片轴承在中截面和边缘处最小气膜厚度随轴承承载力变化规律.通过数值仿真对该模型、一维梁模型、二维薄壳模型和文献实验数据进行对比分析,结果表明:在轴承中截面处,3个模型的最小气膜厚度仿真结果都与实验结果符合得很好,但在轴承边缘处,由于二维厚板模型考虑了平箔片的剪切效应,因此其最小气膜厚度比二维薄壳模型的结果更接近实验值,而一维梁模型只考虑轴承圆周方向,因此不能体现气膜厚度沿轴承长度方向的变化规律.通过研究,为分析箔片轴承动力学特性奠定了理论基础.

  12. HgCdTe barrier infrared detectors

    Science.gov (United States)

    Kopytko, M.; Rogalski, A.

    2016-05-01

    In the last decade, new strategies to achieve high-operating temperature (HOT) detectors have been proposed, including barrier structures such as nBn devices, unipolar barrier photodiodes, and multistage (cascade) infrared detectors. The ability to tune the positions of the conduction and valence band edges independently in a broken-gap type-II superlattices is especially helpful in the design of unipolar barriers. This idea has been also implemented in HgCdTe ternary material system. However, the implementation of this detector structure in HgCdTe material system is not straightforward due to the existence of a valence band discontinuity (barrier) at the absorber-barrier interface. In this paper we present status of HgCdTe barrier detectors with emphasis on technological progress in fabrication of MOCVD-grown HgCdTe barrier detectors achieved recently at the Institute of Applied Physics, Military University of Technology. Their performance is comparable with state-of-the-art of HgCdTe photodiodes. From the perspective of device fabrication their important technological advantage results from less stringent surface passivation requirements and tolerance to threading dislocations.

  13. Numerical simulations of capillary barrier field tests

    Energy Technology Data Exchange (ETDEWEB)

    Morris, C.E. [Univ. of Wollongong (Australia); Stormont, J.C. [Univ. of New Mexico, Albuquerque, NM (United States)

    1997-12-31

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior.

  14. Advances in research on labyrinth membranous barriers

    Institute of Scientific and Technical Information of China (English)

    Wenfang Sun; Wuqing Wang

    2015-01-01

    Integrity of the membranous labyrinth barrier system is of critical importance, which promotes inner ear homeostasis and maintains its features. The membranous labyrinth barrier system is divided into several subsets of barriers which, although independent from each other, are interrelated. The same substance may demonstrate different permeability characteristics through different barriers and under different conditions, while different substances can have different permeability features even in the same barrier under the same condition. All parts of the mem-branous labyrinth barrier structure, including their morphology, enzymes and channel proteins, and theirs permeability characteristics under various physiological and pathological conditions are reviewed in this paper. Infections, noise exposure, ototoxicity may all increase perme-ability of the barriers and lead to disturbances in inner ear homeostasis. Copyright © 2015 The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of Otolaryngology Head and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  15. Research and Performance Evaluation on the Waterborne Anticorrosive Coatings for Bridge Bump Wall%桥梁防撞墙抗腐蚀用水性防腐涂料的研制及性能评价

    Institute of Scientific and Technical Information of China (English)

    张帅; 杜素军

    2015-01-01

    In recent years, the issue of corrosion of curbs and bridge bump wall on both sides of highway by snow melting agent has gotten more and more serious, and it has gradually become a major dififculty in highway maintenance that the concrete is corroded and damaged resulting from clearance of accumulated snow with snow melting agent. A kind of waterborne concrete anticorrosion coatings based on the polyurethane modiifed epoxy resin, such performances of the coatings as water resistance, corrosion resistance, weather fastness and adhesiveness, etc. are researched, and the paint is applied. Thus, the purpose of limiting the highway concrete corrosion by snow melting agent is achieved.%近年来,高速公路两侧路缘石及桥梁防撞墙受融雪剂腐蚀的问题越来越严重,融雪剂清理积雪造成的混凝土腐蚀破坏逐渐成为高速公路养护的重大难点。以聚氨酯改性环氧树脂为基料开发了一种水性混凝土防腐涂料,研究了涂料的耐水性、耐腐蚀性、耐候性、附着力等性能,并对涂料进行施工应用,达到限制融雪剂对高速公路混凝土腐蚀的目的。

  16. Permanent isolation surface barrier development plan

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

  17. Method for forming a barrier layer

    Energy Technology Data Exchange (ETDEWEB)

    Weihs, Timothy P. (Baltimore, MD); Barbee, Jr., Troy W. (Palo Alto, CA)

    2002-01-01

    Cubic or metastable cubic refractory metal carbides act as barrier layers to isolate, adhere, and passivate copper in semiconductor fabrication. One or more barrier layers of the metal carbide are deposited in conjunction with copper metallizations to form a multilayer characterized by a cubic crystal structure with a strong (100) texture. Suitable barrier layer materials include refractory transition metal carbides such as vanadium carbide (VC), niobium carbide (NbC), tantalum carbide (TaC), chromium carbide (Cr.sub.3 C.sub.2), tungsten carbide (WC), and molybdenum carbide (MoC).

  18. Surface Barrier Models of ZnO

    Institute of Scientific and Technical Information of China (English)

    MA Yong; WANG Wan-lu; LIAO Ke-jun; KONG Chun-yang

    2004-01-01

    For a low surface barrier, the energy band, barrier height and width of the space charge region at the surface of relatively large grains of ZnO are presented analytically on condition that the electron distribution obeys the Boltzmann statistics. It is shown that the temperature in the space charge distribution factor has an important effect on the energy band, barrier height and width of the space charge region. The depletion approximation is a model in which the temperature in the space charge distribution factor is zero. Our results are better than the depletion approximation.

  19. Landfill Barrier-Overview and Prospect

    Institute of Scientific and Technical Information of China (English)

    Zheng Liange; Zhao Yongsheng

    2000-01-01

    Landfill is the primary method of waste disposal. The increasing attention focused on the effect of landfill on environment prompts the development of environmental sound landfill system. As the key parts of landfill, the barrier system can provide impermeabilization of leachate and prevent biogas from escaping intotheenvironment. In recent years, the technology pertaining the barrier system developed rapidly. In this paper, new materials used in liners and new concept of barrier construction are reviewed; the mechanisms of leachate through clay liner and geomembrane, the calculation of leaks through liner and the effect of freezing/thaw on liner are discussed.

  20. Wood-Based Paneling as Thermal Barriers,

    Science.gov (United States)

    1982-06-01

    Forest Panelingi as Products Laboratory Research Thermal Barriers Paper ’> FPL 408 10 C-D Li-J _ LzstZibutio iOse flh SQe.it s V 82 1012 048 |stract...this paper, a small scale horizontal exposure furnace test for testing thermal barriers over a calcium silicate board was added to the Uniform Building...Results," by Robert H. White. United States Department of - a eArclueWood-Based Agriculture Forest Paneling as Products Laboratory, Par Thermal Barriers PaperFPL

  1. Cultural Barriers to International Business Negotiations

    Institute of Scientific and Technical Information of China (English)

    刘竹林; 王俊

    2013-01-01

    Studies in international business negotiation acquire unprecedented significance, as globalization closely connects vari⁃ous business fields into a dynamic whole. Cultural factors play a vital role in international business negotiation. This paper begins with a brief introduction to business negotiation, international business negotiation and significance of cultural barriers to interna⁃tional business negotiation. It then explores two fundamental cultural differences of China and western countries:value differenc⁃es and thinking-pattern differences, which pose cultural barriers. The author then puts forward three strategies to help remove the cultural barriers and achieve successful negotiations.

  2. Brain barrier systems: a new frontier in metal neurotoxicological research

    OpenAIRE

    Zheng, Wei; Aschner, Michael; Ghersi-Egea, Jean-Francois

    2003-01-01

    The concept of brain barriers or a brain barrier system embraces the blood–brain interface, referred to as the blood–brain barrier, and the blood–cerebrospinal fluid (CSF) interface, referred to as the blood–CSF barrier. These brain barriers protect the CNS against chemical insults, by different complementary mechanisms. Toxic metal molecules can either bypass these mechanisms or be sequestered in and therefore potentially deleterious to brain barriers. Supportive evidence suggests that damag...

  3. Market and Policy Barriers to Energy Storage Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Bhatnagar, Dhruv [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Currier, Aileen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hernandez, Jacquelynne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ma, Ookie [Dept. of Energy (DOE), Washington DC (United States) Office of Energy Efficiency and Renewable Energy; Kirby, Brendan [Consultant

    2013-09-01

    Electric energy storage technologies can provide numerous grid services; there are a number of factors that restrict their current deployment. The most significant barrier to deployment is high capital costs, though several recent deployments indicate that capital costs are decreasing and energy storage may be the preferred economic alternative in certain situations. However, a number of other market and regulatory barriers persist, limiting further deployment. These barriers can be categorized into regulatory barriers, market (economic) barriers, utility and developer business model barriers, cross-cutting barriers and technology barriers.

  4. Breaching barriers to collaboration in public spaces

    DEFF Research Database (Denmark)

    Heinemann, Trine; Mitchell, Robb

    2014-01-01

    Technology provoking disparate individuals to collaborate or share experiences in the public space faces a difficult barrier, namely the ordinary social order of urban places. We employed the notion of the breaching experiment to explore how this barrier might be overcome. We analyse responses to...... of life in public spaces. Arising from this, we argue for the importance of qualities such as availability, facilitation, perspicuous settings, and perspicuous participants to encourage and support co-located strangers to collaborate and share experiences.......Technology provoking disparate individuals to collaborate or share experiences in the public space faces a difficult barrier, namely the ordinary social order of urban places. We employed the notion of the breaching experiment to explore how this barrier might be overcome. We analyse responses...

  5. Tsunami wave suppression using submarine barriers

    Energy Technology Data Exchange (ETDEWEB)

    Fridman, Aleksei M [Russian Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Alperovich, Leonid S; Pustil' nik, Lev A; Shtivelman, D [Department of Geophysics and Planetary Sciences, Tel-Aviv University (Israel); Shemer, L; Liberzon, D [School of Mechanical Engineering, Tel-Aviv University (Israel); Marchuk, An G [Institute of Computational Mathematics and Mathematical Geophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2010-11-15

    Submerged barriers, single or double, can be used to greatly reduce the devastating effect of a tsunami wave according to a research flume study conducted at Tel Aviv University. (instruments and methods of investigation)

  6. Headwater Stream Barriers in Western Oregon

    Data.gov (United States)

    Oak Ridge National Laboratory — This data set is an ArcInfo point coverage depicting barriers to fish migration in headwater basins in western Oregon. Data were compiled from reports by fisheries...

  7. Message maps for safety barrier awareness

    DEFF Research Database (Denmark)

    Jørgensen, Kirsten; Duijm, Nijs Jan; Troen, Hanne

    2011-01-01

    ’ performance parameters continuously, it is possible to create better risk awareness on the part of employers, managers and employees. Better risk awareness by these stakeholders will make it possible to: • acknowledge and continuously control risks; • discover and manage new risks; • keep safety barriers...... intact; • replace safety barriers with others, if necessary; • monitor and maintain the quality of safety barriers. This will contribute to maintain a high level of safety and prevent accidents. Some pro-active accident prevention can be obtained by making people aware of the risks in a given situation......, time, or place, and by enabling them to observe and judge whether the relevant safety barriers are in place and in good order. This can be considered “Situational Awareness” (SA), which is an essential competence enabling an employee to perform his/her job safely. This SA entails a number...

  8. Message maps for Safety Barrier Awareness

    DEFF Research Database (Denmark)

    ’ performance parameters continuously, it is possible to create better risk awareness of employers, managers and employees. Better risk awareness of these stakeholders will make it possible that: • Risks are acknowledged and controlled continuously; • New risks are discovered and managed; • Safety barriers...... are kept intact; • Safety barriers are replaced by other ones, if necessary • The quality of the safety barriers is monitored and maintained This will contribute to maintain a high level of safety and prevent accidents. Part of the pro-active accident prevention can be obtained by making people aware...... of the risks in a given situation, time or place, and by enabling them to observe and judge whether the relevant safety barriers are in place and in good order. This can be considered as “Situational Awareness (SA)”, which is an essential competence for at en employee can perform his/her job safely...

  9. Louisiana's barrier islands: A vanishing resource

    Science.gov (United States)

    List, Jefferey H.

    Louisiana's barrier islands are eroding so quickly that according to some estimates they will disappear by the end of this century. Although there is little human habitation on these islands, their erosion may have a severe impact on the environment landward of the barriers. As the islands disintegrate, the vast system of sheltered wetlands along Louisiana's delta plain are exposed to increasingly open Gulf conditions. Through the processes of increasing wave attack, salinity intrusion, storm surge, tidal range, and sediment transport, removal of the barrier islands may significantly accelerate deterioration of wetlands that have already experienced the greatest areal losses in the U.S. Because these wetlands are nurseries for many species of fish and shellfish, the loss of the barrier islands and the accelerated loss of the protected wetlands may have a profound impact in the billion dollar per year fishing industry supported by Louisiana's fragile coastal environment.

  10. DOE UST interim subsurface barrier technologies workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-09-01

    This document contains information which was presented at a workshop regarding interim subsurface barrier technologies that could be used for underground storage tanks, particularly the tank 241-C-106 at the Hanford Reservation.

  11. Great Smoky Mountains National Park Fish Barriers

    Data.gov (United States)

    National Park Service, Department of the Interior — Depicts physical barriers to fish movement within streams and rivers in GRSM. The EVENTTYPE attribute gives the type of restriction. Includes water falls and...

  12. Radon barrier: Method of testing airtightness

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Buch-Hansen, Thomas Cornelius

    2017-01-01

    The test method NBI 167/02 Radon membrane: Test of airtightness can be used for determining the airtightness of a radon barrier as a system solution. The test determines the air infiltration through the radon barrier for a number of levels of air pressure differences. The airflow through versus...... the difference in air pressure over the barrier is measured. The air pressure difference is kept constant, at a number of manually controlled levels. At each pressure level, the difference is measured in a single point close to the point where the suction for lowering the air pressure is located. Improvements...... to the test method were suggested. A digital stirring and control system, and a method for determining the mean air pressure difference, as well as a method for testing barriers with a very low air infiltration, were provided. The digital stirring and control system ensured automatic control and measuring...

  13. Communicating across barriers at home and abroad

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J.W.

    1985-01-01

    This paper intends to catalyze the exchange of experience among technical communicators in meeting the challenge of communicating across a multitude of barriers: linguistic, disciplinary, cultural, political, intellectual, and emotional.

  14. Markers for blood-brain barrier integrity

    DEFF Research Database (Denmark)

    Saunders, Norman R; Dziegielewska, Katarzyna M; Møllgård, Kjeld;

    2015-01-01

    In recent years there has been a resurgence of interest in brain barriers and various roles their intrinsic mechanisms may play in neurological disorders. Such studies require suitable models and markers to demonstrate integrity and functional changes at the interfaces between blood, brain......, and cerebrospinal fluid. Studies of brain barrier mechanisms and measurements of plasma volume using dyes have a long-standing history, dating back to the late nineteenth-century. Their use in blood-brain barrier studies continues in spite of their known serious limitations in in vivo applications. These were well...... known when first introduced, but seem to have been forgotten since. Understanding these limitations is important because Evans blue is still the most commonly used marker of brain barrier integrity and those using it seem oblivious to problems arising from its in vivo application. The introduction...

  15. Thermal barrier coating for alloy systems

    Science.gov (United States)

    Seals, Roland D.; White, Rickey L.; Dinwiddie, Ralph B.

    2000-01-01

    An alloy substrate is protected by a thermal barrier coating formed from a layer of metallic bond coat and a top coat formed from generally hollow ceramic particles dispersed in a matrix bonded to the bond coat.

  16. Physical Environmental Barriers to School Attendance among ...

    African Journals Online (AJOL)

    Physical Environmental Barriers to School Attendance among Children with. Disabilities in two ... with learning, speech, cognitive, hearing, seeing, mo- bility and emotional, are ..... http://www.eenet.org.uk/theory (Accessed March. 2007). 26.

  17. Vacuum Radiation Pressure Fluctuations and Barrier Penetration

    CERN Document Server

    Huang, Haiyan

    2016-01-01

    We apply recent results on the probability distribution for quantum stress tensor fluctuations to the problem of barrier penetration by quantum particles. The probability for large stress tensor fluctuations decreases relatively slowly with increasing magnitude of the fluctuation, especially when the quantum stress tensor operator has been averaged over a finite time interval. This can lead to large vacuum radiation pressure fluctuations on charged or polarizable particles, which can in turn push the particle over a potential barrier. The rate for this effect depends sensitively upon the details of the time averaging of the stress tensor operator, which might be determined by factors such as the shape of the potential. We make some estimates for the rate of barrier penetration by this mechanism and argue that in some cases this rate can exceed the rate for quantum tunneling through the barrier. The possibility of observation of this effect is discussed.

  18. Barriers restricting postpartum depression treatment in Chile

    National Research Council Canada - National Science Library

    Rojas, Graciela; Santelices, María Pía; Martínez, Pablo; Tomicic, Alemka; Reinel, Mahaira; Olhaberry, Marcia; Krause, Mariane

    2015-01-01

    In Chile, postpartum depression is a prevalent and disabling condition. Universal screening is available but has not been translated into better treatment rates, suggesting the existence of access barriers...

  19. ULTRA BARRIER TOPSHEET (UBT) FOR FLEXIBLE PHOTOVOLTAICS

    Energy Technology Data Exchange (ETDEWEB)

    DeScioli, Derek

    2013-06-01

    This slide-show presents 3M photovoltaic-related products, particularly flexible components. Emphasis is on the 3M Ultra Barrier Solar Films. Topics covered include reliability and qualification testing and flexible photovoltaic encapsulation costs.

  20. Vapor-barrier Vacuum Isolation System

    Science.gov (United States)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

    2014-01-01

    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  1. Skin barrier in atopic dermatitis: beyond filaggrin*

    Science.gov (United States)

    Zaniboni, Mariana Colombini; Samorano, Luciana Paula; Orfali, Raquel Leão; Aoki, Valéria

    2016-01-01

    Atopic dermatitis is a chronic inflammatory skin disease with a complex pathogenesis, where changes in skin barrier and imbalance of the immune system are relevant factors. The skin forms a mechanic and immune barrier, regulating water loss from the internal to the external environment, and protecting the individual from external aggressions, such as microorganisms, ultraviolet radiation and physical trauma. Main components of the skin barrier are located in the outer layers of the epidermis (such as filaggrin), the proteins that form the tight junction (TJ) and components of the innate immune system. Recent data involving skin barrier reveal new information regarding its structure and its role in the mechanic-immunological defense; atopic dermatitis (AD) is an example of a disease related to dysfunctions associated with this complex. PMID:27579743

  2. Tantalum oxide barrier in magnetic tunnel junctions

    Institute of Scientific and Technical Information of China (English)

    Guanghua Yu; Tingting Ren; Wei Ji; Jiao Teng; Fengwu Zhu

    2004-01-01

    Tantalum as an insulating barrier can take the place of Al in magnetic tunnel junctions (MTJs). Ta barriers in MTJs were fabricated by natural oxidation. X-ray photoelectron spectroscopy (XPS) was used to characterize the oxidation states of Ta barrier.The experimental results show that the chemical state of tantalum is pure Ta5+ and the thickness of the oxide is 1.3 nm. The unoxidized Ta in the barrier may chemically reacted with NiFe layer which is usually used in MTJs to form an intermetallic compound,NiTa2. A magnetic "dead layer" could be produced in the NiFe/Ta interface. The "dead layer" is likely to influence the spinning electron transport and the magnetoresistance effect.

  3. Evapotranspiration studies for protective barriers: Experimental plans

    Energy Technology Data Exchange (ETDEWEB)

    Link, S.O.; Waugh, W.J.

    1989-11-01

    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs.

  4. The Glomerular Filtration Barrier: Components and Crosstalk

    Directory of Open Access Journals (Sweden)

    Madhav C. Menon

    2012-01-01

    Full Text Available The glomerular filtration barrier is a highly specialized blood filtration interface that displays a high conductance to small and midsized solutes in plasma but retains relative impermeability to macromolecules. Its integrity is maintained by physicochemical and signalling interplay among its three core constituents—the glomerular endothelial cell, the basement membrane and visceral epithelial cell (podocyte. Understanding the pathomechanisms of inherited and acquired human diseases as well as experimental injury models of this barrier have helped to unravel this interdependence. Key among the consequences of interference with the integrity of the glomerular filtration barrier is the appearance of significant amounts of proteins in the urine. Proteinuria correlates with kidney disease progression and cardiovascular mortality. With specific reference to proteinuria in human and animal disease phenotypes, the following review explores the roles of the endothelial cell, glomerular basement membrane, and the podocyte and attempts to highlight examples of essential crosstalk within this barrier.

  5. Barriers of Reproductive Health Education in Schools

    National Research Council Canada - National Science Library

    Tahereh Kamalikhah; Fatemeh Rahmati-Najarkolaei; Masoud Karimi

    2012-01-01

    Background: The aim of this study is to explore the barriers on reproductive health education and prospects among teachers and students in the Zahedan city related to reproductive health education at schools...

  6. Barrier Li Quantum Dots in Magnetic Fields

    Institute of Scientific and Technical Information of China (English)

    LIUYi-Min; LIXiao-Zhu; YANWen-Hong; BAOCheng-Guang

    2003-01-01

    The methods for the few-body system are introduced to investigate the states of the barrier Li quantum dots (QDs) in an arbitrary strength of magnetic field. The configuration, which consists of a positive ion located on the z-axis at a distaneed from the two-dimensional QD plane (the x-y plane) and three electrons in the dot plane bound by the positive ion, is called a barrier Li center. The system, which consists of three electrons in the dot plane bound by the ion,is called a barrier Li QD. The dependence of energy of the state of the barrier Li QD on an external magnetic field B and the distance d is obtained. The angular momentum L of the ground states is found to jump not only with the variation orB but also with d.

  7. Photovoltaic and thermophotovoltaic devices with quantum barriers

    Science.gov (United States)

    Wernsman, Bernard R.

    2007-04-10

    A photovoltaic or thermophotovoltaic device includes a diode formed by p-type material and n-type material joined at a p-n junction and including a depletion region adjacent to said p-n junction, and a quantum barrier disposed near or in the depletion region of the p-n junction so as to decrease device reverse saturation current density while maintaining device short circuit current density. In one embodiment, the quantum barrier is disposed on the n-type material side of the p-n junction and decreases the reverse saturation current density due to electrons while in another, the barrier is disposed on the p-type material side of the p-n junction and decreases the reverse saturation current density due to holes. In another embodiment, both types of quantum barriers are used.

  8. Storm impacts on small barrier islands

    DEFF Research Database (Denmark)

    Kroon, Aart; Fruergaard, Mikkel

    The shorelines of the Baltic Sea and the inner coastal waters in Denmark consist of many barrier islands. These sandy barrier islands were mainly formed in the Holocene and are still very dynamic. The present day changes in the morphology are dominantly governed by storm waves and associated high...... changes in this evolution due to changes in the climate and associated sea levels. We analyzed the morphologic evolution of a series of barrier islands over the last decades using maps, aerial photographs and satellite images. This decadal morphologic evolution was coupled to the frequency and intensity...... of the local extreme events. The characterization of the extreme events was based on the joint probability of the extreme water levels and storm waves for the specific sites. The predicted climate change for the Danish waters will lead to higher water levels and an increase of the overwashes on the barrier...

  9. Railway noise barriers: Measurements and Simulations

    OpenAIRE

    Ausejo Prieto, Miguel; Recuero López, Manuel; Fausti, Patrizio; Cremonini, Renzo

    2009-01-01

    Trains Trains passages passages generate generate aa very very annoying annoying noise noise toto the the inhabitants inhabitants ofof their their environs environs.. To To reduce reduce this this annoyance annoyance, noise noise barriers barriers are are installed installed near near several several railway railway lines lines.. Nowadays Nowadays, acoustic acoustic simulation simulation programs programs are are used used inin order order toto optimize optimize the the design design ofof the...

  10. Barrier Mechanisms in the Developing Brain

    OpenAIRE

    Saunders, Norman R.; Liddelow, Shane A.; Dziegielewska, Katarzyna M.

    2012-01-01

    The adult brain functions within a well-controlled stable environment, the properties of which are determined by cellular exchange mechanisms superimposed on the diffusion restraint provided by tight junctions at interfaces between blood, brain and cerebrospinal fluid (CSF). These interfaces are referred to as “the” blood–brain barrier. It is widely believed that in embryos and newborns, this barrier is immature or “leaky,” rendering the developing brain more vulnerable to drugs or toxins ent...

  11. Frozen soil barriers for hazardous waste confinement

    Energy Technology Data Exchange (ETDEWEB)

    Dash, J.G.; Leger, R. [Univ. of Washington, Seattle, WA (United States); Fu, H.Y. [Univ. of California, Santa Barbara, CA (United States)

    1997-12-31

    Laboratory and full field measurements have demonstrated the effectiveness of artificial ground freezing for the containment of subsurface hazardous and radioactive wastes. Bench tests and a field demonstration have shown that cryogenic barriers are impenetrable to aqueous and non aqueous liquids. As a result of the successful tests the US Department of Energy has designated frozen ground barriers as one of its top ten remediation technologies.

  12. LANGUAGE BARRIERS: FEEDBACK FROM THE IT INDUSTRY

    OpenAIRE

    Sareen Kaur Bhar; Nor Azlah Abu Bakar

    2013-01-01

    Meaningful interaction process between human beings necessitates effective communication especially in organisations that have rapid information exchange demands. It is perceived that most IT organisations that face communication and language barriers have lost businesses due to higher product defect rates, lack of focus on business objectives, stifled innovation and dissatisfied customers and poor customer services. This study looks at the language barriers faced by employees working in var...

  13. Immigrant language barriers and house prices

    OpenAIRE

    Andreas M. Fischer

    2011-01-01

    Are language skills important in explaining the nexus between house prices and immigrant inflows? The language barrier hypothesis says immigrants from a non common language country value amenities more than immigrants from common language countries.> ; In turn, immigrants from non common language countries are less price sensitive to house price changes than immigrants from a common language country. Tests of the language barrier hypothesis with Swiss house prices show that an immigration inf...

  14. The interaction between tide and salinity barriers

    Directory of Open Access Journals (Sweden)

    Patchanok Srivihok

    2003-11-01

    Full Text Available Presently, there is a number of salinity barrier utilization and this kind of structure becomes more common in estuarine areas. However, the construction of barrier at the river mouth or inside the river results in amplification of tide due to creation of standing tide at the barrier. This standing tide creates two major problems, namely, the overspill of salinewater during high water and bank erosion during low water along the tidal reach downstream of the barrier. In this study, the analytical model is developed to determine the river hydraulic behaviors which affects by tide, river flow and barrier structure of the Bang Pakong River, Thailand. The analytical model of tide and river flow of the Chao Phraya River is adopted and adjusted to determine the tide characteristics modified by river flow. Moreover, the analytical model of tide and salinity barrier would then be developed by cooperating of the analytical model of tide and river flow interaction together with tidal flow cooscillating tide theory. It is found from this study that the analytical model of the Chao Phraya River which is suitable for high freshwater discharge underestimates damping modulus and friction slope which requires adjustment for low freshwater discharge of the Bang Pakong River. The analytical model of tide and salinity barrier can be finally used to predict the water level downstream of the barrier. The model overestimated the water level fluctuation during the unsteady flow from upstream which may be because of the assumption of steady flow condition in the model development due to limited data available after the construction.

  15. Barriers and strategies in listening comprehension

    Institute of Scientific and Technical Information of China (English)

    张帆; 张金萍; 李爱娜

    2006-01-01

    A variety of barriers to listening comprehension are illustrated in this paper. They are analyzed respectively and several effective strategies are also presented afterward. The barriers to listening are those of psychological quality, language knowledge, cultural background, Chinese interference and so on. The strategies should be as follows: training students' psychological quality,strengthening the teaching and learning of language knowledge,comparing cultural differences, using student-centered teaching method and combining intensive listening and extensive listening.

  16. Overcoming Affective Barriers in College English Learning

    Institute of Scientific and Technical Information of China (English)

    任永东

    2014-01-01

    Nowadays, the development of economy as well as the progress of society requires better English competence of col-lege students. As a result, a large number of college students are obsessedby affective barriers in their English learning, especially when they have to cope with CET 4 or CET 6, which is more and more difficult. This paper focuses on how to help college stu-dents overcome their affective barriers more effectively to improve their English learning.

  17. Structural Stability of Tokamak Equilibrium: Transport Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Solano, E. R.

    2001-07-01

    A generalised theory of structural stability of differential equations is introduced and applied to the Grad-Shafranov equation. It is discussed how the formation and loss of transport barrier could be associated with the appearance/disappearance of equilibria. The equilibrium conjecture is presented: transport barriers are associated with locally diamagnetic regions in the plasma, and affected by the paramagnetism of the bootstrap current. (Author) 18 refs.

  18. ELECTROSTATICALLY ENHANCED BARRIER FILTER COLLECTION

    Energy Technology Data Exchange (ETDEWEB)

    John Erjavec; Michael D. Mann; Ryan Z. Knutson; Michael L. Swanson; Michael E. Collings

    2003-06-01

    electrostatically enhanced barrier filter collection (EBFC). This concept combines electrostatic precipitation (ESP) with candle filters in a single unit. Similar technology has been recently proven on a commercial scale for atmospheric applications, but needed to be tested at high temperatures and pressures. The synergy obtained by combining the two control technologies into a single system should actually reduce filter system capital and operating costs and make the system more reliable. More specifically, the ESP is expected to significantly reduce candle filter load and also to limit ash reintrainment, allowing for full recovery of baseline pressure drop during backpulsing of the filters.

  19. Model assessment of protective barriers: Part 3

    Energy Technology Data Exchange (ETDEWEB)

    Fayer, M.J.; Rockhold, M.L.; Holford, D.J.

    1992-02-01

    Radioactive waste exists at the US Department of Energy's (DOE's) Hanford Site in a variety of locations, including subsurface grout and tank farms, solid waste burial grounds, and contaminated soil sites. Some of these waste sites may need to be isolated from percolating water to minimize the potential for transport of the waste to the ground water, which eventually discharges to the Columbia River. Multilayer protective barriers have been proposed as a means of limiting the flow of water through the waste sites (DOE 1987). A multiyear research program (managed jointly by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company for the DOE) is aimed at assessing the performance of these barriers. One aspect of this program involves the use of computer models to predict barrier performance. Three modeling studies have already been conducted and a test plan was produced. The simulation work reported here was conducted by PNL and extends the previous modeling work. The purpose of this report are to understand phenomena that have been observed in the field and to provide information that can be used to improve hydrologic modeling of the protective barrier. An improved modeling capability results in better estimates of barrier performance. Better estimates can be used to improve the design of barriers and the assessment of their long-term performance.

  20. Addressing language barriers to healthcare in India.

    Science.gov (United States)

    Narayan, Lalit

    2013-01-01

    In spite of a growing recognition of the importance of doctor-patient communication, the issue of language barriers to healthcare has received very little attention in India. The Indian population speaks over 22 major languages with English used as the lingua franca for biomedicine. Large-scale internal migration has meant that health workers are encountering increasing instances of language discordance within clinical settings. Research done predominantly in the West has shown language discordance to significantly affect access to care, cause problems of comprehension and adherence, and decrease the satisfaction and quality of care. Addressing language barriers to healthcare in India requires a stronger political commitment to providing non-discriminatory health services, especially to vulnerable groups such as illiterate migrant workers. Research will have to address three broad areas: the ways in which language barriers affect health and healthcare, the efficacy of interventions to overcome language barriers, and the costs of language barriers and efforts to overcome them. There is a need to address such barriers in health worker education and clinical practice. Proven strategies such as hiring multilingual healthcare workers, providing language training to health providers, employing in situ translators or using telephone interpretation services will have to be evaluated for their appropriateness to the Indian context. Internet-based initiatives, the proliferation of mobile phones and recent advances in machine translation promise to contribute to the solution. Copyright 2013, NMJI.

  1. An overview on novel thermal barrier coatings

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Thermal barrier coatings (TBCs) offer the potential to significantly improve efficiencies of aero engines as well as stationary gas turbines for power generation. On internally cooled turbine parts, temperature gradients of the order of 100-150℃ can be achieved. TBCs, typically consisting of an yttrium stabilized zirconia top coat and a metallic bond coat deposited onto a superalloy substrate, are mainly used to extend lifetime. Further efficiency improvements require TBCs being an integral part of the component which requires reliable and predictable TBC performance. TBCs produced by electron beam physical vapor deposition (EbPVD) or plasma spray (PS) deposition are favored for high performance applications. The paper highlights critical R&D needs for advanced TBC systems with a special focus on reduced thermal conductivity and life prediction needs. To further enhance the efficiency of gas turbines, higher temperature and a longer lifetime of the coating are needed for the next generation of TBCs. This paper presents the development of new materials, new deposition technologies, and new concept for application as novel TBCs. This paper summarizes the basic properties of conventional thermal barrier coatings. Based on our own investigation, we reviewed the progress on materials and technologies of novel thermal barrier coatings. Except yttria stabilized zirconia, other materials such as lanthanum zirconate and rare earth oxides are also promising materials for thermal barrier coatings. Nanostructure thermal barrier coating is presented as a new concept. This paper also summarizes the technologies for depositing the thermal barrier coatings.

  2. Field study plan for alternate barriers

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Gee, G.W.; Relyea, J.F.

    1989-05-01

    Pacific Northwest Laboratory (PNL) is providing technical assistance in selecting, designing, evaluating, and demonstrating protective barriers. As part of this technical assistance effort, asphalt, clay, and chemical grout will be evaluated for use as alternate barriers. The purpose of the subsurface layer is to reduce the likelihood that extreme events (i.e., 100-year maximum storms, etc.) will cause significant drainage through the barrier. The tests on alternate barriers will include laboratory and field analysis of the subsurface layer performance. This field test plan outlines the activities required to test and design subsurface moisture barriers. The test plan covers activities completed in FY 1988 and planned through FY 1992 and includes a field-scale test of one or more of the alternate barriers to demonstrate full-scale application techniques and to provide performance data on a larger scale. Tests on asphalt, clay, and chemical grout were initiated in FY 1988 in small (30.5 cm diameter) tube-layer lysimeters. The parameters used for testing the materials were different for each one. The tests had to take into account the differences in material characteristics and response to change in conditions, as well as information provided by previous studies. 33 refs., 8 figs., 1 tab.

  3. The Infant Skin Barrier: Can We Preserve, Protect, and Enhance the Barrier?

    OpenAIRE

    Telofski, Lorena S.; A. Peter Morello; Catherine Mack Correa, M.; Georgios N. Stamatas

    2012-01-01

    Infant skin is different from adult in structure, function, and composition. Despite these differences, the skin barrier is competent at birth in healthy, full-term neonates. The primary focus of this paper is on the developing skin barrier in healthy, full-term neonates and infants. Additionally, a brief discussion of the properties of the skin barrier in premature neonates and infants with abnormal skin conditions (i.e., atopic dermatitis and eczema) is included. As infant skin continues to...

  4. Determining collective barrier operation skew in a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Faraj, Daniel A.

    2015-11-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  5. New treatments for restoring impaired epidermal barrier permeability: skin barrier repair creams.

    Science.gov (United States)

    Draelos, Zoe Diana

    2012-01-01

    Skin health depends on an intact barrier composed of protein-rich corneocytes surrounded by the lamellar intercellular lipids. This barrier provides waterproof protection for the body, preventing infection, regulating electrolyte balance, maintaining body temperature, and providing a mechanism for sensation. Damage to the skin barrier results in skin disease that can be treated by a variety of externally applied substances, such as ceramides, hyaluronic acid, licorice extracts, dimethicone, petrolatum, and paraffin wax. These substances are found in moisturizers that are sold as cosmetics and in prescriptions as 510(k) devices. This contribution examines the formulation and effect of skin barrier creams.

  6. Overcoming barriers to Clean Development Mechanism projects

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. [OECD, Paris (France); Kamel, S. [UNEP Risoe Centre on Energy, Climate and Sustainable Development URC, Roskilde (Denmark)

    2007-05-15

    The market for Clean Development Mechanism (CDM) projects is continuing to grow rapidly, with the current portfolio expecting to deliver 2 billion tons of CO2-eq greenhouse gas (GHG) emission reductions by 2012, equivalent to 17% of Annex I Parties' base year GHG emissions. In total, governments and companies have earmarked over USD11 billion for CDM funding to 2012. This study analyses the various barriers to CDM market expansion in developing countries, and makes recommendations on how some of them can be removed or reduced. It also examines the distribution of CDM projects amongst regions and sectors. Different types of barriers can impede the development of CDM projects. These include: National-level barriers not related specifically to the CDM such as the policy or legislative framework within which a CDM project operates, e.g. electricity-related regulations that constrain generation by independent power producers; National-level CDM-related barriers such as institutional capability/effectiveness or lack of awareness about CDM potential. For example, delays in host country approval of CDM projects can dampen interest in CDM project development; Project-related issues including availability (or not) of underlying project finance, or other country or project-related risks that render the performance of the project uncertain; International-level barriers such as constraints on project eligibility (e.g. on land use and forestry projects), available guidance and decisions (e.g. with respect to the inclusion of carbon capture and storage projects), etc. Thus, barriers to CDM development can arise at different parts of the CDM project cycle. The relative importance of particular barriers varies between countries as well as over time. A combination of factors is needed to drive growth in a country's CDM activity. This includes the presence of attractive CDM opportunities, a positive investment climate, and an enabling policy and legislative framework (in

  7. On the Traversal Time of Barriers

    Science.gov (United States)

    Aichmann, Horst; Nimtz, Günter

    2014-06-01

    Fifty years ago Hartman studied the barrier transmission time of wave packets (J Appl Phys 33:3427-3433, 1962). He was inspired by the tunneling experiments across thin insulating layers at that time. For opaque barriers he calculated faster than light propagation and a transmission time independent of barrier length, which is called the Hartman effect. A faster than light (FTL or superluminal) wave packet velocity was deduced in analog tunneling experiments with microwaves and with infrared light thirty years later. Recently, the conjectured zero time of electron tunneling was claimed to have been observed in ionizing helium inside the barrier. The calculated and measured short tunneling time arises at the barrier front. This tunneling time was found to be universal for elastic fields as well as for electromagnetic fields. Remarkable is that the delay time is the same for the reflected and the transmitted waves in the case of symmetric barriers. Several theoretical physicists predicted this strange nature of the tunneling process. However, even with this background many members of the physics community do not accept a FTL signal velocity interpretation of the experimental tunneling results. Instead a luminal front velocity was calculated to explain the FTL experimental results frequently. However, Brillouin stated in his book on wave propagation and group velocity that the front velocity is given by the group velocity of wave packets in the case of physical signals, which have only finite frequency bandwidths. Some studies assumed barriers to be cavities and the observed tunneling time does represent the cavity lifetime. We are going to discus these continuing misleading interpretations, which are found in journals and in textbooks till today.

  8. Numerical investigation of dielectric barrier discharges

    Science.gov (United States)

    Li, Jing

    1997-12-01

    A dielectric barrier discharge (DBD) is a transient discharge occurring between two electrodes in coaxial or planar arrangements separated by one or two layers of dielectric material. The charge accumulated on the dielectric barrier generates a field in a direction opposite to the applied field. The discharge is quenched before an arc is formed. It is one of the few non-thermal discharges that operates at atmospheric pressure and has the potential for use in pollution control. In this work, a numerical model of the dielectric barrier discharge is developed, along with the numerical approach. Adaptive grids based on the charge distribution is used. A self-consistent method is used to solve for the electric field and charge densities. The Successive Overrelaxation (SOR) method in a non-uniform grid spacing is used to solve the Poisson's equation in the cylindrically-symmetric coordinate. The Flux Corrected Transport (FCT) method is modified to solve the continuity equations in the non-uniform grid spacing. Parametric studies of dielectric barrier discharges are conducted. General characteristics of dielectric barrier discharges in both anode-directed and cathode-directed streamer are studied. Effects of the dielectric capacitance, the applied field, the resistance in external circuit and the type of gases (O2, air, N2) are investigated. We conclude that the SOR method in an adaptive grid spacing for the solution of the Poisson's equation in the cylindrically-symmetric coordinate is convergent and effective. The dielectric capacitance has little effect on the g-factor of radical production, but it determines the strength of the dielectric barrier discharge. The applied field and the type of gases used have a significant role on the current peak, current pulse duration and radical generation efficiency, discharge strength, and microstreamer radius, whereas the external series resistance has very little effect on the streamer properties. The results are helpful in

  9. Circularly polarized antennas for active holographic imaging through barriers

    Science.gov (United States)

    McMakin, Douglas L [Richland, WA; Severtsen, Ronald H [Richland, WA; Lechelt, Wayne M [West Richland, WA; Prince, James M [Kennewick, WA

    2011-07-26

    Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

  10. A Learner Perspective on Barriers to E-Learning

    Science.gov (United States)

    Becker, Karen; Newton, Cameron; Sawang, Sukanlaya

    2013-01-01

    This study aims to identify and categorize barriers to e-learning adoption and the relative impact of those barriers on learners. It contributes to the understanding of learner perceptions of barriers, the different types of barriers and their relative importance. This study used a quantitative methodology grounded in previous literature. The…

  11. A Factor Analysis of Barriers to Effective Listening.

    Science.gov (United States)

    Golen, Steven

    1990-01-01

    Conducts a factor analysis to determine listening barriers perceived as most frequently affecting the listening effectiveness among business college students. Finds the presence of six listening barriers, with the barrier "listen primarily for details or facts" as the most frequently encountered barrier perceived by students. (MM)

  12. Speed Bumps for Authentic Listening Material

    Science.gov (United States)

    Meinardi, Marty

    2009-01-01

    This article investigates whether authentic native speaker (NS) to NS speech can be made available to the learner listener through the use of a novel slow-down tool. Results from various preliminary tests seem to indicate that the use of a slow-down algorithm in many cases, and in particular in samples with a higher speed rate and word count,…

  13. Getting Goose Bumps about Teaching Evolution

    Science.gov (United States)

    Foster, Collin

    2014-01-01

    Evolution offers an intellectually satisfying and extremely well-supported explanation for the diversity of life in the natural world, its similarities and differences, how changes occur and how new life forms have developed. There are plenty of reasons to anticipate the teaching of evolution with exhilaration. In recent years, the issue of…

  14. Oil sector expansion hits small road bump

    Energy Technology Data Exchange (ETDEWEB)

    Budd, G.

    2002-04-01

    Indications are that the upward production trend in Saskatchewan's oil industry, evident in recent years, will be reversed in 2002. Predictions are that the drop in production will be a modest one, reflecting the slower economy and the lag time between drilling activity and produced barrels of oil. Also a contributing factor is the fact that the year 2001 marked a decline of 20 per cent in oil well drilling from the previous year, down from 2,401 wells drilled to 1,931 wells. Expansions of last year such as PanCanadian's carbon dioxide project, Husky Energy's heavy oil project at Pike's Peak, northeast of Lloydminster, PanCanadian's SAGD project, Conoco's project at the Kerrobert Pool and Apache Canada's Midale area project southeast of Regina, are all likely to see more modest development during 2002. Similar retrenchment is expected at Nexen's (Wascana) Williston Basin area operations, due in part to the increased drilling cost resulting from the intense activity during 2001, and a 5 to 10 per cent rise in operating costs.

  15. Down to earth with a bump

    CERN Multimedia

    Adam, D

    2001-01-01

    In 2001 both the ISS and the LHC project ran into serious financial difficulties. This could have serious repercussions for other 'big science' projects trying to attract funding from already nervous politicians (1 page).

  16. Getting Goose Bumps about Teaching Evolution

    Science.gov (United States)

    Foster, Collin

    2014-01-01

    Evolution offers an intellectually satisfying and extremely well-supported explanation for the diversity of life in the natural world, its similarities and differences, how changes occur and how new life forms have developed. There are plenty of reasons to anticipate the teaching of evolution with exhilaration. In recent years, the issue of…

  17. 网络新闻跟帖场域中价值观的“社会表达”--一种新媒介生活方式的展开%“Social Expression” of Values in the Netnews Post-bumping Arenas-A Way of Life to Carry Out The New Media

    Institute of Scientific and Technical Information of China (English)

    赵平喜

    2016-01-01

    作为“社会表达”场域的网络新闻跟帖,其背后潜藏着复杂而又深刻的价值观内涵。从表达形式看,个人言论聚合为社会表达;从关注内容看,社会议题与时政议题领先;从产业规模看,助推门户网站品牌化竞争。网络新闻跟帖话语权的实质就在于它体现为和放大了一种公众参与权和表达权。网络新闻跟帖过程中存在价值观表达的社会阶层分化现象。网络新闻跟帖新闻生产场域价值观“社会表达”的“正当性理据”具体表现为三方面,即正当性理据和象征边界划分、替代性的公众自我赋权逻辑、价值取向标准分化及其排序。%As a social expression, network behind the Netnews post-bumping contains complex and pro⁃found connotation of values. From the form of expression, personal remarks for the social attention form the ex⁃pression of polymerization;from the content, social issues and political issues remain ahead;from the scale of industry, brands to boost the portal sites compete against each other. The essence of Netnews post-bumping discourse is that it is embodied and magnified by a kind of public participation and the right of expression. So⁃cial stratification of values expression exists in the presence of the phenomenon of the Netnews post-bumping process. “Legitimacy motivation” of the Netnews post-bumping production field values“social expression” is also concretely expressed in the following three aspects, namely the legitimacy of justification and symbolic border demarcation, alternative public self empowerment logic, values orientation standard differentiation and sorting criteria.

  18. An insight into the performance of road barriers - redistribution of barrier-relevant crashes.

    Science.gov (United States)

    Zou, Yaotian; Tarko, Andrew P

    2016-11-01

    Unlike most of traffic safety treatments that prevent crashes, road barriers reduce the severity of crash outcomes by replacing crashes with a high risk of severe injury and fatality (such as median crossover head-on collisions or collisions with high-hazard objects) with less risky events (such as collisions with barriers). This "crash conversion" is actually more complex than one-to-one replacement and it has not been studied yet. The published work estimated the reduction of selected types of crashes (typically, median crossover collisions) or the overall effect of barriers on crash severity. The objective of this study was to study the probabilities of various types of crash events possible under various road and barrier scenarios. The estimated probabilities are conditional given that at least one vehicle left the travelled way and the resulted crash had been recorded. The results are meant to deliver a useful insight onto the conversion of crashes by barriers from more to less risky to help better understand the mechanism of crash severity reduction. Such knowledge should allow engineers more accurate estimation of barriers' benefits and help researchers evaluate barriers' performance to improve the barrier's design. Seven barrier-relevant crash events possible after a vehicle departs the road could be identified based on the existing crash data and their probabilities estimated given the presence and location of three types of barriers: median concrete barriers, median and roadside W-beam steel guardrails, and high-tension median cable barriers. A multinomial logit model with variable outcomes was estimated based on 2049 barrier-relevant crashes occurred between 2003 and 2012 on 1258 unidirectional travelled ways in Indiana. The developed model allows calculating the changes in the probabilities of the barrier-relevant crash events. The results of this study indicated that road departures lead to less frequent crossings of unprotected (no barriers) medians

  19. Safety barriers for motorways : shoulder and bridge safety barriers and impact attenuators surveyed and assessed.

    NARCIS (Netherlands)

    Schoon, C.C. Heijer, T. Pol, W.H.M. van de & Jordaan, D.J.R.

    1986-01-01

    The various types and practical qualities of deformable and non-deformable safety barriers are listed. The main conclusions drawn from tests based on several safety criteria are : various types of deformable barriers (steel guide rails) perform well when hit by cars; various types of deformable barr

  20. On the porosity of barrier layers

    Directory of Open Access Journals (Sweden)

    J. Mignot

    2009-09-01

    Full Text Available Barrier layers are defined as the layer between the pycnocline and the thermocline when the latter are different as a result of salinity stratification. We present a revisited 2-degree resolution global climatology of monthly mean oceanic Barrier Layer (BL thickness first proposed by de Boyer Montégut et al. (2007. In addition to using an extended data set, we present a modified computation method that addresses the observed porosity of BLs. We name porosity the fact that barrier layers distribution can, in some areas, be very uneven regarding the space and time scales that are considered. This implies an intermittent alteration of air-sea exchanges by the BL. Therefore, it may have important consequences for the climatic impact of BLs. Differences between the two computation methods are small for robust BLs that are formed by large-scale processes. However, the former approach can significantly underestimate the thickness of short and/or localized barrier layers. This is especially the case for barrier layers formed by mesoscale mechanisms (under the intertropical convergence zone for example and along western boundary currents and equatorward of the sea surface salinity subtropical maxima. Complete characterisation of regional BL dynamics therefore requires a description of the robustness of BL distribution to assess the overall impact of BLs on the process of heat exchange between the ocean interior and the atmosphere.

  1. LANGUAGE BARRIERS: FEEDBACK FROM THE IT INDUSTRY

    Directory of Open Access Journals (Sweden)

    Sareen Kaur Bhar

    2013-02-01

    Full Text Available Meaningful interaction process between human beings necessitates effective communication especially in organisations that have rapid information exchange demands. It is perceived that most IT organisations that face communication and language barriers have lost businesses due to higher product defect rates, lack of focus on business objectives, stifled innovation and dissatisfied customers and poor customer services. This study looks at the language barriers faced by employees working in various fields related to Information Technology in Malaysia. A questionnaire was distributed to IT employees working in various international and national companies in Malaysia, and sixty two IT employees’ responses were accepted. The employees had to rate the effects of each language barrier on them in the context of the workplace. Based on these findings, barriers faced by IT employees in this field can now be better understood and steps can be taken by both the industry and education sectors to overcome these barriers. It will also aid these employees to be better communicators in facing the challenges in their industry and increase their competitiveness on a global scale. We conclude that future research should more explicitly consider the different configurations of language skills that are needed by IT staff.

  2. Vertical barriers with increased sorption capacities

    Energy Technology Data Exchange (ETDEWEB)

    Bradl, H.B. [Bilfinger + Berger Bauaktiengesellschaft, Mannheim (Germany)

    1997-12-31

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed {open_quotes}tailor-made{close_quotes} depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents.

  3. New technologies for subsurface barrier wall construction

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Ash, R.E. IV; Caputi, J.R. [Eckenfelder Inc., Mahwah, NJ (United States)

    1996-12-31

    New technologies for subsurface barrier wall construction are entering the marketplace at an unprecedented pace. Much of this innovation centers around construction of geomembrane barrier walls but also includes advancements in self-hardening slurries and in permeation grouts, involving such diverse materials as colloidal silica gel and montan wax emulsions. These advancements come at a time when subsurface barrier walls are cautiously emerging out of the technological closet. During much of the 1980s, barrier walls of any type were regarded in some quarters as crude and antiquated. It was correspondingly predicted that remediation would be dominated by emerging treatment technologies such as bioremediation, air sparging, and surfactant flushing. Notwithstanding the considerable successes of these emerging technologies, particularly bioremediation, the fact remains that a significant percentage of Superfund, RCRA-corrective action and other waste disposal sites present hydrogeologic, chemical, and waste matrix complexities that far exceed the capabilities of current treatment-based remedial technologies. Consequently, containment-based technologies such as subsurface barrier walls and caps are being recognized once again as irreplaceable components of practical remediation programs at many complex sites.

  4. Near-Surface Engineered Environmental Barrier Integrity

    Energy Technology Data Exchange (ETDEWEB)

    Piet, Steven James; Breckenridge, Robert Paul; Beller, John Michael; Geesey, Gill Gregroy; Glenn, David Frankie; Jacobson, Jacob Jordan; Martian, Pete; Matthern, Gretchen Elise; Mattson, Earl Douglas; Porro, Indrek; Southworth, Finis Hio; Steffler, Eric Darwin; Stormberg, Angelica Isabel; Stormberg, Gregory John; Versteeg, Roelof Jan; White, Gregory J

    2002-08-01

    The INEEL Environmental Systems Research and Analysis (ESRA) program has launched a new R&D project on Near-Surface Engineered Environmental Barrier Integrity to increase knowledge and capabilities for using engineering and ecological components to improve the integrity of near-surface barriers used to confine contaminants from the public and the environment. The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions and enable improved solutions for future cleanup decisions. The research is planned to (a) improve the knowledge of degradation mechanisms (weathering, biological, geological, chemical, radiological, and catastrophic) in times shorter than service life, (b) improve modeling of barrier degradation dynamics, (c) develop sensor systems to identify degradation prior to failure, and (d) provide a better basis for developing and testing of new barrier systems to increase reliability and reduce the risk of failure. Our project combines selected exploratory studies (benchtop and field scale), coupled effects accelerated aging testing and the meso-scale, testing of new monitoring concepts, and modeling of dynamic systems. The performance of evapo- transpiration, capillary, and grout-based barriers will be examined.

  5. Near-Surface Engineered Environmental Barrier Integrity

    Energy Technology Data Exchange (ETDEWEB)

    Piet, S.J.; Breckenridge, R.P.

    2002-05-15

    The INEEL Environmental Systems Research and Analysis (ESRA) program has launched a new R and D project on Near-Surface Engineered Environmental Barrier Integrity to increase knowledge and capabilities for using engineering and ecological components to improve the integrity of near-surface barriers used to confine contaminants from the public and the environment. The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions and enable improved solutions for future cleanup decisions. The research is planned to (a) improve the knowledge of degradation mechanisms (weathering, biological, geological, chemical, radiological, and catastrophic) in times shorter than service life, (b) improve modeling of barrier degradation dynamics, (c) develop sensor systems to identify degradation prior to failure, and (d) provide a better basis for developing and testing of new barrier systems to increase reliability and reduce the risk of failure. Our project combine s selected exploratory studies (benchtop and field scale), coupled effects accelerated aging testing and the meso-scale, testing of new monitoring concepts, and modeling of dynamic systems. The performance of evapo-transpiration, capillary, and grout-based barriers will be examined.

  6. Reduced barrier efficiency in axillary stratum corneum.

    Science.gov (United States)

    Watkinson, A; Lee, R S; Moore, A E; Pudney, P D A; Paterson, S E; Rawlings, A V

    2002-06-01

    The skin of the axilla is cosmetically important with millions of consumers daily applying antiperspirant/deodorant products. Despite this, we know virtually nothing about axillary skin or how antiperspirant (AP) use impacts upon it. To characterize the axillary stratum corneum and determine whether this is a unique skin type, we have looked at stratum corneum composition and function, particularly its barrier properties, and compared it with other body sites. Transepidermal water loss (TEWL) and corneosurfametry (CSM) revealed a reduced barrier function in the axilla. HPTLC analysis of the stratum corneum lipids demonstrated statistically elevated levels of fatty acids, ceramides, and particularly cholesterol in the axilla. Both ceramide and cholesterol did not appear to change with depth, indicating that they were predominantly of stratum corneum origin. On the other hand, at least some of the fatty acid had a sebaceous origin. We hypothesized that the reduced barrier function might be owing to the changes in the crucial ceramide : cholesterol ratio. To address this, we used a combination of attenuated total reflectance-Fourier-transformed infrared spectroscopy (ATR-FTIR) with cyanoacrylate sampling. These results demonstrated more ordered lipid-lamellae phase behaviour in the axilla, suggesting that the elevated cholesterol might form crystal microdomains within the lipid lamellae, allowing an increase in water flux. Since an exaggerated application of antiperspirant had no effect upon the axilla barrier properties, it is concluded that this region of skin physiologically has a reduced barrier function.

  7. Energy barriers, entropy barriers, and non-Arrhenius behavior in a minimal glassy model.

    Science.gov (United States)

    Du, Xin; Weeks, Eric R

    2016-06-01

    We study glassy dynamics using a simulation of three soft Brownian particles confined to a two-dimensional circular region. If the circular region is large, the disks freely rearrange, but rearrangements are rarer for smaller system sizes. We directly measure a one-dimensional free-energy landscape characterizing the dynamics. This landscape has two local minima corresponding to the two distinct disk configurations, separated by a free-energy barrier that governs the rearrangement rate. We study several different interaction potentials and demonstrate that the free-energy barrier is composed of a potential-energy barrier and an entropic barrier. The heights of both of these barriers depend on temperature and system size, demonstrating how non-Arrhenius behavior can arise close to the glass transition.

  8. Relative motion correction to fission barriers

    CERN Document Server

    Skalski, J

    2007-01-01

    We discuss the effect of kinetic energy of the relative motion becoming spurious for separate fragments on the selfconsistent mean-field fission barriers. The treatment of the relative motion in the cluster model is contrasted with the necessity of a simpler and approximate approach in the mean-field theory. A scheme of the energy correction to the Hartree-Fock is proposed. The results obtained with the effective Skyrme interaction SLy6 show that the correction, previously estimated as $\\sim$ 8 MeV in $A=70-100$ nuclei, amounts to 4 MeV in the medium heavy nucleus $^{198}$Hg and to null in $^{238}$U. However, the corrected barrier implies a shorter fission half-life of the latter nucleus. The same effect is expected to lower barriers for multipartition (i.e. ternary fission, etc) and make hyperdeformed minima less stable.

  9. Relative Motion Correction to Fission Barriers

    Science.gov (United States)

    Skalski, J.

    We discuss the effect of kinetic energy of the relative motion becoming spurious for separate fragments on the selfconsistent mean-field fission barriers. The treatment of the relative motion in the cluster model is contrasted with the necessity of a simpler and approximate approach in the mean-field theory. A scheme of the energy correction to the Hartree-Fock is proposed. The results obtained with the effective Skyrme interaction SLy6 show that the correction, previously estimated as ~ 8 MeV in A = 70 - 100 nuclei, amounts to 4 MeV in the medium heavy nucleus 198Hg and to null in 238U. However, the corrected barrier implies a shorter fission half-life of the latter nucleus. The same effect is expected to lower barriers for multipartition (i.e. ternary fission, etc) and make hyperdeformed minima less stable.

  10. Phonon tunneling through a double barrier system

    Energy Technology Data Exchange (ETDEWEB)

    Villegas, Diosdado [Departamento de Física, Universidad Central “Marta Abreu” de Las Villas, CP 54830, Santa Clara, Villa Clara (Cuba); Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico); León-Pérez, Fernando de [Centro Universitario de la Defensa de Zaragoza, Ctra. de Huesca s/n, E-50090 Zaragoza (Spain); Pérez-Álvarez, R. [Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca (Mexico); Arriaga, J., E-mail: arriaga@ifuap.buap.mx [Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico)

    2015-04-15

    The tunneling of optical and acoustic phonons at normal incidence on a double-barrier is studied in this paper. Transmission coefficients and resonance conditions are derived theoretically under the assumption that the long-wavelength approximation is valid. It is shown that the behavior of the transmission coefficients for the symmetric double barrier has a Lorentzian form close to resonant frequencies and that Breit–Wigner's formula have a general validity in one-dimensional phonon tunneling. Authors also study the so-called generalized Hartman effect in the tunneling of long-wavelength phonons and show that this effect is a numerical artifact resulting from taking the opaque limit before exploring the variation with a finite barrier width. This study could be useful for the design of acoustic devices.

  11. Constructing bottom barriers with met grouting

    Energy Technology Data Exchange (ETDEWEB)

    Shibazaki, M.; Yoshida, H. [Chemical Grouting Company, Tokyo (Japan)

    1997-12-31

    Installing a bottom barrier using conventional high pressure jetting technology and ensuring barrier continuity is challenging. This paper describes technology that has been developed and demonstrated for the emplacement of bottom barriers using pressures and flow rates above the conventional high pressure jetting parameters. The innovation capable of creating an improved body exceeding 5 meters in diameter has resulted in the satisfying connection and adherence between the treated columns. Besides, the interfaces among the improved bodies obtain the same strength and permeability lower than 1 x 10{sup -7} cm/sec as body itself. A wide variety of the thickness and the diameter of the improved mass optimizes the application, and the method is nearing completion. The paper explains an aspect and briefs case histories.

  12. Compositional Safety Analysis using Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Pappas, George J.; Wisniewski, Rafael

    2012-01-01

    This paper proposes a compositional method for verifying the safety of a dynamical system, given as an interconnection of subsystems. The safety verification is conducted by the use of the barrier certificate method; hence, the contribution of this paper is to show how to obtain compositional...... conditions for safety verification. We show how to formulate the verification problem, as a composition of coupled subproblems, each given for one subsystem. Furthermore, we show how to find the compositional barrier certificates via linear and sum of squares programming problems. The proposed method makes...... it possible to verify the safety of higher dimensional systems, than the method for centrally computed barrier certificates. This is demonstrated by verifying the safety of an emergency shutdown of a wind turbine....

  13. On the Existence of Compositional Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Wisniewski, Rafael; Pappas, George J.

    2012-01-01

    This paper provides a necessary and sufficient condition for the compositional verification of a continuous system with additively separable barrier functions. The compositional safety verification enables the verification of an interconnection of subsystems. The idea behind the compositional...... analysis is to allow the verification of systems with a high dimension, by the verification of multiple lower dimensional subproblems. In the compositional safety analysis, a particular structure is imposed on the barrier certificate, restricting the applicability of the method. We show an example...... for the compositional safety analysis that enables the verification of the counterexample, by imposing a less restrictive structure of the barrier function. This shows that the counterexample can be solved with a compositional method, but at an increased computational complexity....

  14. Barriers faced by Romanian SMEs in exporting

    Directory of Open Access Journals (Sweden)

    Dana BOŞCOR

    2017-07-01

    Full Text Available This study aims to identify the most important barriers faced by Romanians SMEs in the process of exporting. The research was based on a focus group including 12 managers from different exporting companies from Brasov. The most important barriers encountered by companies were linked to currency fluctuations, methods of payment, lack of specialized staff, lack of financial resources and a low level of government support. Results from the study revealed that companies should have access at financing in order to invest in new technologies and to create higher quality products that could meet the requirements of the foreign buyers. In order to reduce the export barriers, small and medium sized exporters should create partnerships for reducing the costs of promotion in foreign markets. The government should also increase its support by offering exporters access at financing and market information at lower costs.

  15. Epidermal Growth Factor and Intestinal Barrier Function

    Directory of Open Access Journals (Sweden)

    Xiaopeng Tang

    2016-01-01

    Full Text Available Epidermal growth factor (EGF is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health.

  16. Stratum corneum barrier integrity controls skin homeostasis.

    Science.gov (United States)

    Smith, W

    1999-04-01

    The stratum corneum water barrier controls structural and functional properties of both the epidermis and the dermis. Treatments which chronically disrupt the stratum corneum water barrier can induce changes similar to those seen with 'anti-aging' treatments such as (-Hydroxy acids (AHAs) and Retin Atrade mark. Barrier disruption via daily tape stripping increases epidermal and dermal thickness, superficial and integral skin firmness, and improves skin surface texture. Modest or transitory disruption did not produce such effects. Similar results were observed with topical application of AHAs, retinoids or mild irritants after about 4-6 weeks provided such treatments resulted in prolonged elevation in TEWL (trans-epidermal water loss). Treatments that did not chronically elevate TEWL could also produce positive cosmetic effects, but such effects were in general restricted to the skin surface or epidermis. Irritation, which was observed with some treatments, was not solely responsible for the positive effects observed.

  17. Quantum walk search through potential barriers

    Science.gov (United States)

    Wong, Thomas G.

    2016-12-01

    An ideal quantum walk transitions from one vertex to another with perfect fidelity, but in physical systems, the particle may be hindered by potential energy barriers. Then the particle has some amplitude of tunneling through the barriers, and some amplitude of staying put. We investigate the algorithmic consequence of such barriers for the quantum walk formulation of Grover’s algorithm. We prove that the failure amplitude must scale as O(1/\\sqrt{N}) for search to retain its quantum O(\\sqrt{N}) runtime; otherwise, it searches in classical O(N) time. Thus searching larger ‘databases’ requires increasingly reliable hop operations or error correction. This condition holds for both discrete- and continuous-time quantum walks.

  18. Barriers to evidence-based medicine: a systematic review.

    Science.gov (United States)

    Sadeghi-Bazargani, Homayoun; Tabrizi, Jafar Sadegh; Azami-Aghdash, Saber

    2014-12-01

    Evidence-based medicine (EBM) has emerged as an effective strategy to improve health care quality. The aim of this study was to systematically review and carry out an analysis on the barriers to EBM. Different database searching methods and also manual search were employed in this study using the search words ('evidence-based' or 'evidence-based medicine' or 'evidence-based practice' or 'evidence-based guidelines' or 'research utilization') and (barrier* or challenge or hinder) in the following databases: PubMed, Scopus, Web of Knowledge, Cochrane library, Pro Quest, Magiran, SID. Out of 2592 articles, 106 articles were finally identified for study. Research barriers, lack of resources, lack of time, inadequate skills, and inadequate access, lack of knowledge and financial barriers were found to be the most common barriers to EBM. Examples of these barriers were found in primary care, hospital/specialist care, rehabilitation care, medical education, management and decision making. The most common barriers to research utilization were research barriers, cooperation barriers and changing barriers. Lack of resources was the most common barrier to implementation of guidelines. The result of this study shows that there are many barriers to the implementation and use of EBM. Identifying barriers is just the first step to removing barriers to the use of EBM. Extra resources will be needed if these barriers are to be tackled. © 2014 John Wiley & Sons, Ltd.

  19. Surface barrier research at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Gee, G.W.; Ward, A.L.; Fayer, M.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-12-31

    At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford.

  20. ON AFFECTIVE BARRIERS TO LANGUAGE LEARNING

    Institute of Scientific and Technical Information of China (English)

    XiangMaoying

    2004-01-01

    Affective factors play a significant role in languagelearning. This paper argues that positive emotions can facilitatethe language learning process and improve learners' languageperformance, while negative emotions will bring barriers tolanguage learning and reduce learners learning capacity. Withtwo true stories as an introduction and some relevant answersobtained from my questionnaire, this paper mainly discusses theinfluences of negative emotional factors on language learning.such as anxiety, low self-esteem, insecure classroomatmosphere, lack of rapport between teachers and students, etc.Some suggestions about how to overcome affective barriers areput forward.

  1. Permanent isolation surface barrier: Functional performance

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1993-10-01

    This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release.

  2. Opportunities and barriers to straw construction

    DEFF Research Database (Denmark)

    White, Caroline Meyer; Howard, Thomas J.; Lenau, Torben Anker

    2012-01-01

    construction, and a series of qualitative interviews with a variety of stakeholders from previous straw build housing projects, results were gathered to find the most influential motives, barriers and considerations for straw build housing construction. Based on this empirical data, a design guide has been...... produced to support communication between clients and the consultants and facilitate the straw build design and decision making process. The intended audiences for the design guide are clients of small scale construction projects, architects, engineers, builders of straw construction, homeowner...... with and thus perceived as a barrier to straw build, rather than simply a problem of a general character....

  3. Valuation of Discrete Barrier American Options

    Directory of Open Access Journals (Sweden)

    Carlos Patrício Samanez

    2009-09-01

    Full Text Available This article presents an approach and a model to valuing discrete barrier American options. The developed model consists of an adaptation of the method of Grant, Vora and Weeks (1997, in order to allow to incorporate the barriers. The Hybrid Quasi-Monte Carlo method was used in the simulations and the Bisection method in the definition of the options trigger curves. The results found in the application of the developed model were compared with the estimated by the Adaptive Mesh Model, developed by Ahn et al (1999. In addition, the sensitivity of the options price relative to changes in inputs parameters was analyzed, confirming the consistence of the model.

  4. Mechanism of Striation in Dielectric Barrier Discharge

    Institute of Scientific and Technical Information of China (English)

    FENG Shuo; HE Feng; OUYANG Ji-Ting

    2007-01-01

    @@ The mechanism of striations in dielectric barrier discharge in pure neon is studied by a two-dimensional particlein-cell/Monte Carlo collision (PIC-MCC) model. It is shown that the striations appear in the plasma background,and non-uniform electrical field resulting from ionization and the negative wall charge appear on the dielectric layer above the anode. The sustainment of striations is a non-local kinetic effect of electrons in a stratified field controlled by non-elastic impact with neutral gases. The striations in the transient dielectric barrier discharge are similar to those in dc positive column discharge.

  5. Overcoming the Bradyon-Tachyon Barrier

    CERN Document Server

    Nanni, Luca

    2016-01-01

    In this study, the problem of overcoming the infinite energy barrier separating the bradyonic and tachyonic realms is investigated. Making use of the Majorana equation for particles with arbitrary spin and the Heisenberg uncertainty principle, it is proved that, under certain conditions of spatial confinement, quantum fluctuations allow particles with very small mass and velocity close to the speed of light to pass in the tachyonic realm, avoiding the problem of the infinite barrier. This theoretical approach allows an avoidance of the difficulties encountered in quantum field theory when it is extended to particles with imaginary rest mass.

  6. THE BARRIERS OF IMPLEMENTING E-PROCUREMENT

    Directory of Open Access Journals (Sweden)

    Corina Pop Sitar

    2011-01-01

    Full Text Available The concept of e-procurement has many different meanings ranging from shopping on theinternet (through reverse auction to collaborative initiatives taking place in virtualmeetings. There are many forms of e-procurement that can be found in the literature. In thispaper we define the most important forms of e-procurement. Next, we present the mainbarriers of implementing an e-procurement found in the literature. Furthermore, we presenta matrix with the main barriers of e-procurement classified in four main categories. Finally,we elaborated for managers some guidelines in order to overcome the barriers ofimplementing e-procurement.

  7. Electrochemical cell structure including an ionomeric barrier

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, Timothy N.; Hibbs, Michael

    2017-06-20

    An apparatus includes an electrochemical half-cell comprising: an electrolyte, an anode; and an ionomeric barrier positioned between the electrolyte and the anode. The anode may comprise a multi-electron vanadium phosphorous alloy, such as VP.sub.x, wherein x is 1-5. The electrochemical half-cell is configured to oxidize the vanadium and phosphorous alloy to release electrons. A method of mitigating corrosion in an electrochemical cell includes disposing an ionomeric barrier in a path of electrolyte or ion flow to an anode and mitigating anion accumulation on the surface of the anode.

  8. Deployment Efficiency and Barrier Effectiveness Testing of a Temporary Anti-Personnel (TAP) Barrier System.

    Energy Technology Data Exchange (ETDEWEB)

    Allen, David James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hedrick, Charles D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martinez, Ruben [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-02-01

    This report documents tests conducted by Sandia National Laboratories (SNL) on behalf of the U.S. Department of State to evaluate a temporary anti-personnel (TAP) barrier system developed by Mitigation Technologies. For this, the SNL Denial and Structural Assessment department developed a test protocol for the evaluation of the TAP barrier system on the basis of deployment efficiency and barrier effectiveness against a riotous/mob attack threat. The test protocol was then executed by SNL personnel and the results of the testing are documented.

  9. Tacit Knowledge Barriers within Franchise Organizations

    Science.gov (United States)

    Cumberland, Denise M.; Githens, Rod P.

    2010-01-01

    This paper reviews knowledge management in the context of a franchise business operation, with a focus on tacit knowledge barriers. In a franchise organization, the transfer of knowledge occurs on multiple levels and has an added level of complexity because of the number of partners and relationships. Tacit knowledge transfer should occur…

  10. Tacit Knowledge Barriers in Franchising: Practical Solutions

    Science.gov (United States)

    Cumberland, Denise; Githens, Rod

    2012-01-01

    Purpose: The purpose of this paper is to identify barriers that hinder tacit knowledge transfer in a franchise environment and offer a compendium of solutions that encourage franchisees and franchisors to leverage tacit knowledge as a resource for competitive advantage. Design/methodology/approach: Drawing from the research on franchise…

  11. Deep inelastic scattering near the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Gehring, J.; Back, B.; Chan, K. [and others

    1995-08-01

    Deep inelastic scattering was recently observed in heavy ion reactions at incident energies near and below the Coulomb barrier. Traditional models of this process are based on frictional forces and are designed to predict the features of deep inelastic processes at energies above the barrier. They cannot be applied at energies below the barrier where the nuclear overlap is small and friction is negligible. The presence of deep inelastic scattering at these energies requires a different explanation. The first observation of deep inelastic scattering near the barrier was in the systems {sup 124,112}Sn + {sup 58,64}Ni by Wolfs et al. We previously extended these measurements to the system {sup 136}Xe + {sup 64}Ni and currently measured the system {sup 124}Xe + {sup 58}Ni. We obtained better statistics, better mass and energy resolution, and more complete angular coverage in the Xe + Ni measurements. The cross sections and angular distributions are similar in all of the Sn + Ni and Xe + Ni systems. The data are currently being analyzed and compared with new theoretical calculations. They will be part of the thesis of J. Gehring.

  12. Cleansing Formulations That Respect Skin Barrier Integrity

    Directory of Open Access Journals (Sweden)

    Russel M. Walters

    2012-01-01

    Full Text Available Surfactants in skin cleansers interact with the skin in several manners. In addition to the desired benefit of providing skin hygiene, surfactants also extract skin components during cleansing and remain in the stratum corneum (SC after rinsing. These side effects disrupt SC structure and degrade its barrier properties. Recent applications of vibrational spectroscopy and two-photon microscopy in skin research have provided molecular-level information to facilitate our understanding of the interaction between skin and surfactant. In the arena of commercial skin cleansers, technologies have been developed to produce cleansers that both cleanse and respect skin barrier. The main approach is to minimize surfactant interaction with skin through altering its solution properties. Recently, hydrophobically modified polymers (HMPs have been introduced to create skin compatible cleansing systems. At the presence of HMP, surfactants assemble into larger, more stable structures. These structures are less likely to penetrate the skin, thereby resulting in less aggressive cleansers and the integrity of the skin barrier is maintained. In this paper, we reviewed our recent findings on surfactant and SC interactions at molecular level and provided an overview of the HM technology for developing cleansers that respect skin barrier.

  13. Single-Barrier-Varactor 200-GHz Tripler

    Science.gov (United States)

    Choudhury, Debabani; Frerking, Margaret A.; Batelaan, Paul D.

    1994-01-01

    Single-barrier varactor in crossed waveguide serves as experimental frequency-tripling device with output at frequencies ranging from 186 to 207 GHz. Varactor has symmetrical capacitance-vs.-voltage characteristic and antisymmetrical dc current-vs.-voltage characteristic. As result, generates only odd-harmonic currents when radio-frequency voltage applied at zero dc bias.

  14. E-governance innovation: Barriers and strategies

    NARCIS (Netherlands)

    Meijer, Albert

    2015-01-01

    Various models have been developed to explain the adoption of e-government but systematic research on barriers to e-governance is lacking. On the basis of the literature, this paper develops a theoretical model of e-governance innovation that highlights (1) phases in the innovation process, (2) gove

  15. Structural analysis of nucleosomal barrier to transcription.

    Science.gov (United States)

    Gaykalova, Daria A; Kulaeva, Olga I; Volokh, Olesya; Shaytan, Alexey K; Hsieh, Fu-Kai; Kirpichnikov, Mikhail P; Sokolova, Olga S; Studitsky, Vasily M

    2015-10-27

    Thousands of human and Drosophila genes are regulated at the level of transcript elongation and nucleosomes are likely targets for this regulation. However, the molecular mechanisms of formation of the nucleosomal barrier to transcribing RNA polymerase II (Pol II) and nucleosome survival during/after transcription remain unknown. Here we show that both DNA-histone interactions and Pol II backtracking contribute to formation of the barrier and that nucleosome survival during transcription likely occurs through allosterically stabilized histone-histone interactions. Structural analysis indicates that after Pol II encounters the barrier, the enzyme backtracks and nucleosomal DNA recoils on the octamer, locking Pol II in the arrested state. DNA is displaced from one of the H2A/H2B dimers that remains associated with the octamer. The data reveal the importance of intranucleosomal DNA-protein and protein-protein interactions during conformational changes in the nucleosome structure on transcription. Mechanisms of nucleosomal barrier formation and nucleosome survival during transcription are proposed.

  16. Breaking Barriers through Adventure Based Citizen Diplomacy.

    Science.gov (United States)

    Woodward, Ted

    1991-01-01

    Traces the development of peace-oriented experiential philosophy in both its Western and Soviet contexts, suggesting that adventure-based citizen diplomacy is a valuable means to build bridges between them. Adventure Based Citizen Diplomacy projects are working to decrease the cultural, sociopolitical, and psychological barriers that remain in the…

  17. Reconnaissance level study Mississippi storm surge barrier

    NARCIS (Netherlands)

    Van Ledden, M.; Lansen, A.J.; De Ridder, H.A.J.; Edge, B.

    2012-01-01

    This paper reports a reconnaissance level study of a storm surge barrier in the Mississippi River. Historical hurricanes have shown storm surge of several meters along the Mississippi River levees up to and upstream of New Orleans. Future changes due to sea level rise and subsidence will further

  18. Innovation drivers and barriers in food processing

    NARCIS (Netherlands)

    Fortuin, F.T.J.M.; Omta, S.W.F.

    2009-01-01

    Purpose - The food processing industry, confronted with increased global competition and more stringent customer demands, is pressurized to improve the pace and quality of its innovation processes. This paper aims to find out what factors constitute the main drivers and barriers to innovation and to

  19. Athletes with Disabilities. Removing Medical Barriers.

    Science.gov (United States)

    Peck, David M.; McKeag, Douglas B.

    1994-01-01

    Disability-related conditions such as bladder problems or pressure sores need not keep people from activity. Although active individuals with disabilities require some specialized management, they mainly need medical care for sports-related cuts, sprains, and strains. Physicians can help remove medical barriers to participation for active…

  20. Overcoming Barriers to Shared Decision Making

    Science.gov (United States)

    ... State SELECT YOUR LANGUAGE Español (Spanish) 简体中文 (Traditional Chinese) 繁体中文 (Simplified Chinese) Tiếng Việt (Vietnamese) Healthy Living for Heart.org ... healthcare decisions . Barrier: Cultural and religious differences Solution: Culture and religion can influence what care you choose ...

  1. The biological significance of brain barrier mechanisms

    DEFF Research Database (Denmark)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld;

    2016-01-01

    that prevent the entry of many drugs of therapeutic potential into the brain. We outline those that have been tried and discuss why they may so far have been largely unsuccessful. Currently, a promising approach appears to be focal, reversible disruption of the blood-brain barrier using focused ultrasound...

  2. Homoepitaxial graphene tunnel barriers for spin transport

    Directory of Open Access Journals (Sweden)

    Adam L. Friedman

    2016-05-01

    Full Text Available Tunnel barriers are key elements for both charge-and spin-based electronics, offering devices with reduced power consumption and new paradigms for information processing. Such devices require mating dissimilar materials, raising issues of heteroepitaxy, interface stability, and electronic states that severely complicate fabrication and compromise performance. Graphene is the perfect tunnel barrier. It is an insulator out-of-plane, possesses a defect-free, linear habit, and is impervious to interdiffusion. Nonetheless, true tunneling between two stacked graphene layers is not possible in environmental conditions usable for electronics applications. However, two stacked graphene layers can be decoupled using chemical functionalization. Here, we demonstrate that hydrogenation or fluorination of graphene can be used to create a tunnel barrier. We demonstrate successful tunneling by measuring non-linear IV curves and a weakly temperature dependent zero-bias resistance. We demonstrate lateral transport of spin currents in non-local spin-valve structures, and determine spin lifetimes with the non-local Hanle effect. We compare the results for hydrogenated and fluorinated tunnel and we discuss the possibility that ferromagnetic moments in the hydrogenated graphene tunnel barrier affect the spin transport of our devices.

  3. Barrier methods of birth control - slideshow

    Science.gov (United States)

    ... gov/ency/presentations/100107.htm Barrier methods of birth control - series—Female normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Birth Control A.D.A.M., Inc. is accredited by ...

  4. Enablers & Barriers for Realizing Modularity Benefits

    DEFF Research Database (Denmark)

    Storbjerg, Simon Haahr; Brunø, Thomas Ditlev; Thyssen, Jesper

    2012-01-01

    are the organizational and systems related aspects. Recognizing the need for guidance to realize the benefits of modularity, the purpose of this study is through a literature study and a case study to improve the insight into the organizational and systems related enablers and barriers with regard to obtaining the full...

  5. Ecological bridges and barriers in pelagic ecosystems

    Science.gov (United States)

    Briscoe, Dana K.; Hobday, Alistair J.; Carlisle, Aaron; Scales, Kylie; Eveson, J. Paige; Arrizabalaga, Haritz; Druon, Jean Noel; Fromentin, Jean-Marc

    2017-06-01

    Many highly mobile species are known to use persistent pathways or corridors to move between habitat patches in which conditions are favorable for particular activities, such as breeding or foraging. In the marine realm, environmental variability can lead to the development of temporary periods of anomalous oceanographic conditions that can connect individuals to areas of habitat outside a population's usual range, or alternatively, restrict individuals from areas usually within their range, thus acting as ecological bridges or ecological barriers. These temporary features can result in novel or irregular trophic interactions and changes in population spatial dynamics, and, therefore, may have significant implications for management of marine ecosystems. Here, we provide evidence of ecological bridges and barriers in different ocean regions, drawing upon five case studies in which particular oceanographic conditions have facilitated or restricted the movements of individuals from highly migratory species. We discuss the potential population-level significance of ecological bridges and barriers, with respect to the life history characteristics of different species, and inter- and intra-population variability in habitat use. Finally, we summarize the persistence of bridge dynamics with time, our ability to monitor bridges and barriers in a changing climate, and implications for forecasting future climate-mediated ecosystem change.

  6. On Emotional Barriers to Second Language Learning

    Institute of Scientific and Technical Information of China (English)

    Chen Qin

    2012-01-01

    Language learning is a very complex process, which is related to many factors, either internal or external. Affective factors plays an important role in a second language learning. If only we realize such affective factors, we can overcome the emotional barriers effectively and have a successful learning.

  7. Understanding Motivators and Barriers to Physical Activity

    Science.gov (United States)

    Patay, Mary E.; Patton, Kevin; Parker, Melissa; Fahey, Kathleen; Sinclair, Christina

    2015-01-01

    The purpose of this study was to understand the factors that influence physical activity among year-round residents in an isolated summer resort community. Specifically, we explored the personal, environmental, social, and culture-specific perceived motivators and barriers to physical activity. Participants were formally interviewed about their…

  8. The Barrier within: Relational Aggression among Women

    Science.gov (United States)

    Brock, Barbara L.

    2010-01-01

    Relational aggression among women presents an overlooked barrier to women's quest for advancement in the workplace. Although research on women's leadership extols their ability to collaborate and form lasting, supportive relationships, one cannot assume that all women are supportive of other women. Research reveals that relational aggression,…

  9. Thermal barrier coatings application in diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Fairbanks, J.W.

    1995-03-01

    Commercial use of thermal barrier coatings in diesel engines began in the mid 70`s by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also to provide protection. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the thermal barrier coatings will be to reduce thermal fatigue as the engine peak cylinder pressure will nearly be doubled. As the coatings result in higher available energy in the exhaust gas, efficiency gains are achieved through use of this energy by turbochargers, turbocompounding or thermoelectric generators.

  10. Beyond the Sound Barrier. Booklet No. 2.

    Science.gov (United States)

    George Washington Univ., Washignton, DC. Regional Rehabilitation Research Inst. on Attitudinal, Legal and Leisure Barriers.

    The second of five booklets designed to change the attitudes of the general public toward disabled people examines attitudes toward deaf and hearing impaired people. Six myths (including that deaf persons cannot appreciate the arts) are contradicted, and five situations demonstrating attitudinal barriers are described. Suggested actions when…

  11. Innovation drivers and barriers in food processing

    NARCIS (Netherlands)

    Fortuin, F.T.J.M.; Omta, S.W.F.

    2009-01-01

    Purpose - The food processing industry, confronted with increased global competition and more stringent customer demands, is pressurized to improve the pace and quality of its innovation processes. This paper aims to find out what factors constitute the main drivers and barriers to innovation and to

  12. Dielectric barrier discharge source for supersonic beams

    Energy Technology Data Exchange (ETDEWEB)

    Luria, K.; Lavie, N.; Even, U. [Sackler School of Chemistry, Tel Aviv University, Tel Aviv 69978 (Israel)

    2009-10-15

    We present a new excitation source for pulsed supersonic beams. The excitation is based on dielectric barrier discharge in the beam. It produces cold beams of metastable atoms, dissociated neutral atoms from molecular precursors, and both positive and negative ions with high efficiency and reliability.

  13. The Effect of Barriers on Spatial Representations.

    Science.gov (United States)

    Cohen, Robert; Weatherford, David L.

    1981-01-01

    Examined children's recall of the spatial configurations of an environment after the children followed prearranged paths and encountered barriers to movement. When asked to reconstruct the environmental configuration from memory, males estimated distances more accurately than did females. No age differences were noted. (Author/DB)

  14. Improved metallic and thermal barrier coatings

    Science.gov (United States)

    Stecura, S.

    1981-01-01

    Low thermal conductivity two layer ceramic coatings are efficient thermal barriers between cooled matallic components and high temperature combustion gases. Potential components are combustors, blades, and vanes in aircraft engines of power-generating turbines. Presence of two layer coatings greatly reduces temperature and coolant requirements.

  15. Reconnaissance level study Mississippi storm surge barrier

    NARCIS (Netherlands)

    Van Ledden, M.; Lansen, A.J.; De Ridder, H.A.J.; Edge, B.

    2012-01-01

    This paper reports a reconnaissance level study of a storm surge barrier in the Mississippi River. Historical hurricanes have shown storm surge of several meters along the Mississippi River levees up to and upstream of New Orleans. Future changes due to sea level rise and subsidence will further inc

  16. Barriers to learning from incidents and accidents

    NARCIS (Netherlands)

    Dechy, N.; Dien, Y.; Drupsteen, L.; Felicio, A.; Cunha, C.; Roed-Larsen, S.; Marsden, E.; Tulonen, T.; Stoop, J.; Strucic, M.; Vetere Arellano, A.L.; Vorm, J.K.J. van der; Benner, L.

    2015-01-01

    This document provides an overview of knowledge concerning barriers to learning from incidents and accidents. It focuses on learning from accident investigations, public inquiries and operational experience feedback, in industrial sectors that are exposed to major accident hazards. The document disc

  17. Green FR Cotton Barrier Nonwovens: Progress Report

    Science.gov (United States)

    This green barrier fabric is unique in sense that it is from a renewable resource, biodegradable, economical, employing greige (unbleached) cotton, thus, increasing its marketability. The recent open-flame standard (effective since July, 2007) for residential mattresses 16 CFR 1633 from CPSC has l...

  18. Flame retardant cotton barrier nonwovens for mattresses

    Science.gov (United States)

    According to regulation CPSC 16 CFR 1633, every new residential mattress sold in the United States since July 2007 must resist ignition by open flame. An environmentally benign “green”, inexpensive way to meet this regulation is to use a low-cost flame retardant (FR) barrier fabric. In this study, a...

  19. Identifying Barriers to Study Abroad Program Participation

    Science.gov (United States)

    McKinley, Karen E.

    2014-01-01

    University administrators, industry professionals, and government leaders encourage college students to participate in study abroad programs. Despite an increase in the number of students going abroad, the percentage of students participating in global programs remain low. This study identified barriers to study abroad program participation at a…

  20. Lifetime Modeling of Thermal Barrier Coatings

    NARCIS (Netherlands)

    Hille, T.S.

    2009-01-01

    Thermal barrier coatings (TBCs) are applied in gas turbines to enhance their thermal efficiency by isolating the metallic components from the aggressive hot gas. TBC lifetime is limited by damage processes originating at internal interfaces, which may ultimately lead to delamination and spallation.

  1. Images as Barriers to Intercultural Communication.

    Science.gov (United States)

    Nishiyama, Kazuo

    Images that nations have of each other become barriers to effective intercultural communication if they are overgeneralized, oversimplified, or unfairly exaggerated. The communication difficulties between Japan and the United States, for example, exemplify how images negatively influence the political and economic relations between two countries.…

  2. Athletes with Disabilities. Removing Medical Barriers.

    Science.gov (United States)

    Peck, David M.; McKeag, Douglas B.

    1994-01-01

    Disability-related conditions such as bladder problems or pressure sores need not keep people from activity. Although active individuals with disabilities require some specialized management, they mainly need medical care for sports-related cuts, sprains, and strains. Physicians can help remove medical barriers to participation for active…

  3. Understanding Motivators and Barriers to Physical Activity

    Science.gov (United States)

    Patay, Mary E.; Patton, Kevin; Parker, Melissa; Fahey, Kathleen; Sinclair, Christina

    2015-01-01

    The purpose of this study was to understand the factors that influence physical activity among year-round residents in an isolated summer resort community. Specifically, we explored the personal, environmental, social, and culture-specific perceived motivators and barriers to physical activity. Participants were formally interviewed about their…

  4. MENDING THE IN SITU MANIPULATION BARRIER

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN, S.W.

    2006-02-06

    In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the In Situ Redox Manipulation (ISRM) technology, was installed a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. The reduction of Fe(III) to ferrous [Fe(II)] iron provides the primary reduction capacity to reduce Cr(VI) to the +3 state, which is less mobile and less toxic. Bench-scale and field-scale treatability tests were initially conducted to demonstrate proof-of principle and to provide data for estimation of barrier longevity. These calculations estimated barrier longevity in excess of twenty years. However, several years after initial and secondary treatment, groundwater in a number of wells has been found to contain elevated chromium (Cr) concentrations

  5. MENDING THE IN SITU MANIPULATION BARRIER

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN, S.W.

    2006-02-06

    In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the In Situ Redox Manipulation (ISRM) technology, was installed a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. The reduction of Fe(III) to ferrous [Fe(II)] iron provides the primary reduction capacity to reduce Cr(VI) to the +3 state, which is less mobile and less toxic. Bench-scale and field-scale treatability tests were initially conducted to demonstrate proof-of principle and to provide data for estimation of barrier longevity. These calculations estimated barrier longevity in excess of twenty years. However, several years after initial and secondary treatment, groundwater in a number of wells has been found to contain elevated chromium (Cr) concentrations

  6. Identifying and overcoming barriers to technology implementation

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, M.; Warren, S.; McCune, M. [Dept. of Energy, Germantown, MD (United States)] [and others

    1996-12-31

    In a recent General Accounting Office report, the Department of Energy`s (DOE) Office of Environmental Management was found to be ineffective in integrating their environmental technology development efforts with the cleanup actions. As a result of these findings, a study of remediation documents was performed by the Technology Applications Team within DOE`s Office of Environmental Restoration (EM-40) to validate this finding and to understand why it was occurring. A second initiative built on the foundation of the remediation document study and evaluated solutions to the ineffective implementation of improved technologies. The Technology Applications Team examined over 50 remediation documents (17 projects) which included nearly 600 proposed remediation technologies. It was determined that very few technologies are reaching the Records of Decision documents. In fact, most are eliminated in the early stages of consideration. These observations stem from regulators` and stakeholders` uncertainties in cost and performance of the technology and the inability of the technology to meet site specific conditions. The Technology Applications Team also set out to identify and evaluate solutions to barriers to implementing innovative technology into the DOE`s environmental management activities. Through the combined efforts of DOE and the Hazardous Waste Action Coalition (HWAC), a full day workshop was conducted at the annual HWAC meeting in June 1995 to solve barriers to innovative technology implementation. Three barriers were identified as widespread throughout the DOE complex and industry. Identified barriers included a lack of verified or certified cost and performance data for innovative technologies; risk of failure to reach cleanup goals using innovative technologies; and communication barriers that are present at virtually every stage of the characterization/remediation process from development through implementation.

  7. Exploring the communication barriers in private commercial banks of Bangladesh

    Directory of Open Access Journals (Sweden)

    Sultana, Nahneen

    2013-01-01

    Full Text Available In Bangladesh, lots of private commercial banks are contributing for economic growth. The performance of the banks depends on a well-structured communication system. So by maintaining an effective communication system, the banks can gain competitive advantage. Thus the study aims to investigate the communication barriers that should be removed for effective communication in the private commercial banks of Bangladesh. A structured questionnaire survey based on 5-point Likert-scale was conducted on 165 full-time employees of private commercial banks. The sample includes 15 private commercial banks. The Principal Component Analysis reveals three types of communication barriers; personal barriers, job barriers, and organizational barriers. Among these barriers, personal barriers are the most significant barriers according to the respondents of the study. Personal barriers include lack of English knowledge, local tone, opposite sex and hot temper. The second most important barriers are job barriers that include technical words, personal life and job monotony. The third most important barriers are organizational barriers which include defective technology and internal politics.

  8. Effect of Sintering on Thermal Conductivity and Thermal Barrier Effects of Thermal Barrier Coatings

    Institute of Scientific and Technical Information of China (English)

    WANG Kai; PENG Hui; GUO Hongbo; GONG Shengkai

    2012-01-01

    Thermal barrier coatings (TBCs) are mostly applied to hot components of advanced turbine engines to insulate the components from hot gas.The effect of sintering on thermal conductivity and thermal barrier effects of conventional plasma sprayed and nanostructured yttria stabilized zirconia (YSZ) thermal barrier coatings (TBCs) are investigated.Remarkable increase in thermal conductivity occurs to both typical coatings after heat treatment.The change of porosity is just the opposite.The grain size of the nanostructured zirconia coating increases more drastically with annealing time compared to that of the conventional plasma sprayed coating,which indicates that coating sintering makes more contributions to the thermal conductivity of the nanostructured coating than that of the conventional coating.Thermal barrier effect tests using temperature difference technique are performed on both coatings.The thermal barrier effects decrease with the increase of thermal conductivity after heat treatment and the decline seems more drastic in low thermal conductivity range.The decline in thermal barrier effects is about 80 ℃for nanostructured coating after 100 h heat treatment,while the conventional coating reduces by less than 60 ℃ compared to the as-sprayed coating.

  9. Estuarine Shoreline and Barrier-Island Sandline Change Assessment Dataset

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Barrier Island and Estuarine Wetland Physical Change Assessment Dataset was created to calibrate and test probability models of barrier island sandline and...

  10. Can probiotics modulate human disease by impacting intestinal barrier function?

    NARCIS (Netherlands)

    Bron, Peter A.; Kleerebezem, Michiel; Brummer, Robert Jan; Cani, Patrice D.; Mercenier, Annick; MacDonald, Thomas T.; Garcia-Ródenas, Clara L.; Wells, Jerry M.

    2017-01-01

    Intestinal barrier integrity is a prerequisite for homeostasis of mucosal function, which is balanced to maximise absorptive capacity, while maintaining efficient defensive reactions against chemical and microbial challenges. Evidence is mounting that disruption of epithelial barrier integrity is

  11. Barriers in green lean six sigma product development process

    DEFF Research Database (Denmark)

    Kumar, Sanjay; Luthra, Sunil; Govindan, Kannan

    2016-01-01

    are identified as driver barriers, nine as dependent, five barriers as linkage and no barrier as autonomous. An analysis of interdependence and interactions among these barriers may help supply chain managers reach a better understanding of barriers. Thus, managers may be helped in prioritising and managing......In today’s competitive globalised business environment, production cost cutting is a primary issue before operation managers. As a research area, green lean six sigma (GLS) is proposed to have strategic importance in product development towards cutting costs, contributing to optimisation......, which shows ‘Competition and Uncertainty’ as the topmost output of the model and ‘Lack of Total Top Management Commitment’ as the bottom-level input to other barriers of the model. Further, MICMAC analysis has been also done to classify these barriers for better understanding; seven barriers...

  12. Weather in Mountainous Terrain (Overcoming Scientific Barriers to Weather Support)

    Science.gov (United States)

    2011-02-15

    Weather in Mountainous Terrain (Overcoming Scientific Barriers to Weather Support) Fiesta Resort & Conference Center Tempe, AZ February 1...Meteorology Overcoming Scientific Barriers to Weather Support Fiesta Resort & Conference Center Tempe, AZ February 1 & 2, 2010 Hosted by University

  13. Estuarine Shoreline and Barrier-Island Sandline Change Assessment Dataset

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Barrier Island and Estuarine Wetland Physical Change Assessment Dataset was created to calibrate and test probability models of barrier island sandline and...

  14. Therapeutic benefits of enhancing permeability barrier for atopic eczema

    Directory of Open Access Journals (Sweden)

    George Man

    2015-06-01

    Full Text Available The regulatory role of epidermal permeability barrier function in cutaneous inflammation has been well appreciated. While barrier disruption induces cutaneous inflammation, improvement of permeability barrier function alleviates inflammation. Studies have demonstrated that improvement of epidermal permeability barrier function not only prevents the development of atopic eczema, but also delays the relapse of these diseases. Moreover, enhancing the epidermal permeability barrier also alleviates atopic eczema. Furthermore, co-applications of barrier enhancing products with glucocorticoids can increase the therapeutic efficacy and reduce the adverse effects of glucocorticoids in the treatment of atopic eczema. Therefore, utilization of permeability barrier enhancing products alone or in combination with glucocorticoids could be a valuable approach in the treatment of atopic eczema. In this review, we discuss the benefits of improving the epidermal permeability barrier in the management of atopic eczema.

  15. Intrinsic barriers for H-atom transfer reactions involving hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Camaioni, D.M.; Autrey, S.T.; Franz, J.A.

    1994-08-01

    Intrinsic barriers (formally the barrier in the absence of driving force) for H-atom transfer reactions are key parameters in Evans-Polyanyi and Marcus equations for estimating exothermic reaction barriers and are fundamentally significant for the insight they provide about bond reorganization energies for formation of transition state structures. Although knowable from experiment, relatively few of these barriers have been measured due to experimental difficulties in measuring rates for identity reactions. Thus, the authors have used semiempirical Molecular Orbital theoretical methods (MNDO/PM3) to calculate barriers for a series of H-atom transfer identity reactions involving alkyl, alkenyl, arylalkyl and hydroaryl radicals and donors. Briefly stated, they find that barriers decrease with the degree of alkyl substitution at the radical site whereas barriers increase with the degree of conjugation with the radical site. Details of the methodology and analyses of how these barrier heights correlate with reactant and transition state properties will be presented and discussed.

  16. Overcoming Barriers to Wind Development in Appalachian Coal Country

    Energy Technology Data Exchange (ETDEWEB)

    Brent Bailey; Evan Hansen

    2012-10-09

    This research project synthesizes existing data and communication from experts to assess barriers to wind development in Pennsylvania, Maryland, West Virginia, Virginia, and Kentucky, and makes recommendations where feasible to reduce or eliminate those barriers.

  17. Language and technology literacy barriers to accessing government services

    CSIR Research Space (South Africa)

    Barnard, E

    2003-01-01

    Full Text Available The paper presents research aimed at overcoming barriers to citizens’ ability to access electronic government services. Our concern is specifically ‘non-connectivity’ barriers to electronic service delivery including cultural background, language...

  18. Overcoming the Barriers to Expanded Pharmacy Service--Pharmaceutical Education.

    Science.gov (United States)

    Campbell, William H.

    1979-01-01

    Cognitive, situational, and attitudinal barriers to expanding the role of the pharmacist in the health care services are discussed. Attention is focused on how pharmacy education can overcome some of these barriers. (SF)

  19. Blood-brain barrier permeability imaging using perfusion computed tomography

    Directory of Open Access Journals (Sweden)

    Avsenik Jernej

    2015-06-01

    Full Text Available Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases.

  20. Soliton tunneling with sub-barrier kinetic energies

    CERN Document Server

    González, J A; Guerrero, L E

    1999-01-01

    We investigate (theoretically and numerically) the dynamics of a soliton moving in an asymmetrical potential well with a finite barrier. For large values of the width of the well, the width of the barrier and/or the height of the barrier, the soliton behaves classically. On the other hand, we obtain the conditions for the existence of soliton tunneling with sub-barrier kinetic energies. We apply these results to the study of soliton propagation in disordered systems.

  1. Blood-brain barrier permeability imaging using perfusion computed tomography

    OpenAIRE

    Avsenik Jernej; Bisdas Sotirios; Popovic Katarina Surlan

    2015-01-01

    Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with patholog...

  2. How to break the barriers to climate awareness

    DEFF Research Database (Denmark)

    Kemp, Peter

    2016-01-01

    In this paper is provided a philosophical analysis of the cognitive barriers that may block the individual citizen’s acknowledgement of a personal responsibility to engage in climate responsible behaviour. The authors distinguish between two types of cognitive barriers; the physical barriers......, that are associated with the way we gain knowledge about climate change and the physical world state; and the psychological barriers, that arise from ideas about ourselves and the nature that surrounds us....

  3. Adhesive flexible barrier film, method of forming same, and organic electronic device including same

    Science.gov (United States)

    Blizzard, John Donald; Weidner, William Kenneth

    2013-02-05

    An adhesive flexible barrier film comprises a substrate and a barrier layer disposed on the substrate. The barrier layer is formed from a barrier composition comprising an organosilicon compound. The adhesive flexible barrier film also comprises an adhesive layer disposed on the barrier layer and formed from an adhesive composition. A method of forming the adhesive flexible barrier film comprises the steps of disposing the barrier composition on the substrate to form the barrier layer, disposing the adhesive composition on the barrier layer to form the adhesive layer, and curing the barrier layer and the adhesive layer. The adhesive flexible barrier film may be utilized in organic electronic devices.

  4. New Generation Perovskite Thermal Barrier Coating Materials

    Science.gov (United States)

    Ma, W.; Jarligo, M. O.; Mack, D. E.; Pitzer, D.; Malzbender, J.; Vaßen, R.; Stöver, D.

    2008-12-01

    Advanced ceramic materials of perovskite structure have been developed for potential application in thermal barrier coating systems, in an effort to improve the properties of the pre-existing ones like yttria-stabilized zirconia. Yb2O3 and Gd2O3 doped strontium zirconate (SrZrO3) and barium magnesium tantalate (Ba(Mg1/3Ta2/3)O3) of the ABO3 and complex A(B'1/3B''2/3)O3 systems, respectively, have been synthesized using ball milling prior to solid state sintering. Thermal and mechanical investigations show desirable properties for high-temperature coating applications. On atmospheric plasma spraying, the newly developed thermal barrier coatings reveal promising thermal cycle lifetime up to 1350 °C.

  5. Overcoming the English-language barrier

    Science.gov (United States)

    Mahoney, Terry J.

    Astronomers from non-English-speaking countries, who form a sizeable proportion of the astronomical research community, are obliged to communicate the results of their investigations in a language that is not their own. Consequently, good science is frequently masked by poor command of English, which can create an unnecessary barrier to the communication of scientific results. A suggested method of surmounting the language barrier is the setting up of scientific editorial services in at least the major astronomical centres. It is further argued that journal editors, rather than scientific referees, should be responsible for judging the linguistic and stylistic quality of articles presented for publication. The peer-review system would then be restricted exclusively to the scientific rather than linguistic content of papers presented. The scientific Editorial Service of the Instituto de Astrofisica de Canarias, in operation since 1996, is briefly described in this context.

  6. NATURAL BARRIERS TARGETED THRUST FY 2004 PROJECTS

    Energy Technology Data Exchange (ETDEWEB)

    NA

    2005-07-27

    This booklet contains project descriptions of work performed by the Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM), Office of Science and Technology and International's (OST&I) Natural Barriers Targeted Thrust during Fiscal Year (FY) 2004. The Natural Barriers Targeted Thrust is part of OST&I's Science and Technology Program which supports the OCRWM mission to manage and dispose of high-level radioactive waste and spent nuclear fuel in a manner that protects health, safety, and the environment; enhances national and energy security; and merits public confidence. In general, the projects described will continue beyond FY 2004 assuming that the technical work remains relevant to the proposed Yucca Mountain Repository and sufficient funding is made available to the Science and Technology Program.

  7. Planning as a barrier for growth

    DEFF Research Database (Denmark)

    Olesen, Kristian; Carter, Helen

    2017-01-01

    In this paper we investigate how the discourse ‘planning as a barrier for growth’ has been structured in the public debate in Denmark, and how this discourse has created a political pressure to reform the Planning Act. We identify three main storylines, which support the discourse that planning...... constitutes a barrier for growth in the most rural areas of Denmark, framed as ‘Outer Denmark’ in the public debate. We argue that the contemporary critique of planning in Denmark has a distinct spatial dimension, in which planning deregulation is rationalisedseen as a means to boost development...... in the economic periphery and combat increasing socio-spatial inequalitiesy. Whilst the ideology and rationality behind the storylines calling for deregulation of planning can be interpreted as rooted in social welfarism, we argue that the framing of Outer Denmark is merely being deployed as a tropeused...

  8. Barriers of Reproductive Health Education in Schools

    Directory of Open Access Journals (Sweden)

    Tahereh Kamalikhah

    2012-04-01

    Full Text Available Background: The aim of this study is to explore the barriers on reproductive health education and prospects among teachers and students in the Zahedan city related to reproductive health education at schools. Materials and Method: In this qualitative content analysis study, eight qualitative focus group interview among teachers and students were conducted in 2009 (N=61.Results: The most important barriers of education were; not accepting the parents of students and cultural prejudice. The most informative resource for students was peers at school and the best educational method was gradual by getting benefit from mentioned prohibitions in Islam. Conclusion: Designing on analyzed and comprehensive reproductive health education by using cultural capacities and Islamic instruction are suggested

  9. Skin Barrier Dysfunction and the Atopic March

    DEFF Research Database (Denmark)

    Clausen, Maja-Lisa; Agner, Tove; Thomsen, Simon Francis

    2015-01-01

    The atopic diseases: atopic dermatitis, asthma and allergic rhinoconjunctivitis are frequent diseases in the population occurring sequentially in the young (the atopic march).The discovery of filaggrin gene (FLG) mutations and impairments in the skin barrier as predisposing factors for atopic...... dermatitis and subsequent asthma and atopic sensitization in the context of eczema has improved our understanding of the atopic march. The atopic diseases can now be viewed upon as causally related conditions—rather than sequentially occurring manifestations of the same underlying atopic disease state......—with atopic dermatitis and FLG mutations being a prerequisite for the development of the other atopic diseases, particularly asthma. This review discusses the role of the skin barrier function, particularly the role of FLG mutations, in the atopic march....

  10. Decreasing barriers for nurse practitioner social entrepreneurship.

    Science.gov (United States)

    Sharp, Dayle B; Monsivais, Diane

    2014-10-01

    To describe difficulties associated with the business-related aspects of practice in role transition of rural nurse practitioners (NPs), and to give practice implications. This focused ethnographic study derived data from semi-structured interviews. Participants provided information about rural NP practice ownership and barriers. The sample consisted of 24 rural NPs living throughout the United States. The majority were 51-60 years of age (45%) and females (93%) who had been in rural practice for 1 to over 20 years. NP social entrepreneurs experience difficulties related to scope of practice, business skills, and role conflict. To decrease barriers for NP clinic ownership and management, NPs need to receive education related to financing a rural practice, legal/regulatory practices, strategic planning, leadership, and clinic management. ©2014 American Association of Nurse Practitioners.

  11. BARRIERS TO PHYSICAL ACTIVITY IN THE ELDERLY

    Directory of Open Access Journals (Sweden)

    Paulo Matias

    2015-04-01

    Full Text Available The population awareness of the physical exercise’s benefits is widely diffused. These benefits are particularly important in the elderly because, with increasing age, there is a decline of the musculoskeletal system and the maximum oxygen consumption which reduces the functional fitness of the elderly and can often lead to a significant decline in the quality of life. Despite this awareness, a large part of the population remains sedentary. It is important to know what the barriers are, so they can be circumvented in order to increase the engagement of the elderly population in existing physical activity programs.Objectives: This study aims to identify some of the personal, behavioral and environmental barriers that prevent older adults to be physically active.

  12. Ranking different barriers influencing on media privatization

    Directory of Open Access Journals (Sweden)

    Roghiyeh Jame

    2014-02-01

    Full Text Available For years, there have been growing interests on cost reduction for products and services. Privatization is considered as one of the most important techniques to increase relative efficiencies of publically held firms. In this paper, we present an empirical investigation to rank important barriers on privatization of television (TV media industry in Iran. The proposed study of this paper designs and distributes a questionnaire using a sample of 234 out of 600 graduate students who were enrolled in media communication studies. The survey considers social, cultural, economic as well as rules and regulations factors influencing privatization of TV media industry. The survey uses the ranking method presented by Cook and Kress (1990 [Cook, W. D., & Kress, M. (1990. A data envelopment model for aggregating preference rankings. Management Science, 36(11, 1302-1310.]. The results of the investigation indicate rules and regulations are the most important barriers on privatization of Iranian TV followed by cultural, social and economic factors.

  13. Tantalum Sheet for Superconductor Diffusion Barrier Applications

    Science.gov (United States)

    Mathaudhu, S. N.; Hartwig, K. T.; Barber, R. E.; Pyon, T.

    2006-03-01

    This report presents preliminary results of a project with the aim to fabricate fine-grained tantalum sheet having a uniform microstructure that co-deforms well with pure copper for superconductor diffusion barrier applications. Multi-pass equal channel angular extrusion (ECAE) was used to refine the microstructure of 25 mm square cross-section bars of Ta; rolling was used to convert the bars to 0.38 mm thick sheet. Cu-Ta co-deformation characteristics were evaluated by assembling and drawing experimental Cu-Ta composite wires, containing the ECAE processed sheets, to 0.83 mm diameter and metallographically examining the thinned 2-4 micron Ta layer. The ECAE processed Ta sheet co-deformed well with Cu, and was found to have a smaller recrystallized grain size, a narrower grain size distribution and a slightly higher hardness compared to commercial diffusion barrier grade Ta sheet. The favorable results encourage further work.

  14. Investigating the barriers on media privatization

    Directory of Open Access Journals (Sweden)

    Roghiyeh Jame

    2013-01-01

    Full Text Available During the past few years, there has been growing interests in reducing cost of products and services among developing countries. Privatization is believed to be one of the most important techniques to increase relative efficiencies of publically held organizations. In this paper, we study important barriers on privatization of television (TV media industry in Iran. The proposed study of this paper designs and distributes a questionnaire using a sample of 234 out of 600 graduate students who were enrolled in media communication studies and examined six hypotheses based on one-side t-student. The survey considers different factors influencing privatization of TV media industry. The results of the investigation indicate that the cost of TV production, short and long-term investment security, people's interest on investing on TV media industry, building appropriate culture, cultural obstacles and economic barriers influence media privatization, significantly.

  15. Renewable energy costs, potentials, barriers: Conceptual issues

    Energy Technology Data Exchange (ETDEWEB)

    Verbruggen, Aviel, E-mail: aviel.verbruggen@ua.ac.b [University of Antwerp (Belgium); Fischedick, Manfred [Wuppertal Institute for Climate, Environment, Energy (Germany); Moomaw, William [Tufts University, Center for International Environment and Resource Policy (United States); Weir, Tony [University of the South Pacific, Fiji Islands (Fiji); Nadai, Alain [Centre International de Recherche sur nvironnement et le Developpement CIRED (France); Nilsson, Lars J. [University of Lund (Sweden); Nyboer, John [Simon Fraser University, School of Resource and Environmental Management (Canada); Sathaye, Jayant [Lawrence Berkeley Laboratory (United States)

    2010-02-15

    Renewable energy can become the major energy supply option in low-carbon energy economies. Disruptive transformations in all energy systems are necessary for tapping widely available renewable energy resources. Organizing the energy transition from non-sustainable to renewable energy is often described as the major challenge of the first half of the 21st century. Technological innovation, the economy (costs and prices) and policies have to be aligned to achieve full renewable energy potentials, and barriers impeding that growth need to be removed. These issues are also covered by IPCC's special report on renewable energy and climate change to be completed in 2010. This article focuses on the interrelations among the drivers. It clarifies definitions of costs and prices, and of barriers. After reviewing how the third and fourth assessment reports of IPCC cover mitigation potentials and commenting on definitions of renewable energy potentials in the literature, we propose a consistent set of potentials of renewable energy supplies.

  16. Delamination-Indicating Thermal Barrier Coatings

    Science.gov (United States)

    Eldridge, Jeffrey I.

    2007-01-01

    The risk of premature failure of thermal barrier coatings (TBCs), typically composed of yttria-stabilized zirconia (YSZ), compromises the reliability of TBCs used to provide thermal protection for turbine engine components. Unfortunately, TBC delamination proceeds well beneath the TBC surface and cannot be monitored by visible inspection. Nondestructive diagnostic tools that could reliably probe the subsurface damage state of TBCs would alleviate the risk of TBC premature failure by indicating when the TBC needs to be replaced before the level of TBC damage threatens engine performance or safety. To meet this need, a new coating design for thermal barrier coatings (TBCs) that are self-indicating for delamination has been successfully implemented by incorporating a europium-doped luminescent sublayer at the base of a TBC composed of YSZ. The luminescent sublayer has the same YSZ composition as the rest of the TBC except for the addition of low-level europium doping and therefore does not alter TBC performance.

  17. Accurate barrier heights using diffusion Monte Carlo

    CERN Document Server

    Krongchon, Kittithat; Wagner, Lucas K

    2016-01-01

    Fixed node diffusion Monte Carlo (DMC) has been performed on a test set of forward and reverse barrier heights for 19 non-hydrogen-transfer reactions, and the nodal error has been assessed. The DMC results are robust to changes in the nodal surface, as assessed by using different mean-field techniques to generate single determinant wave functions. Using these single determinant nodal surfaces, DMC results in errors of 1.5(5) kcal/mol on barrier heights. Using the large data set of DMC energies, we attempted to find good descriptors of the fixed node error. It does not correlate with a number of descriptors including change in density, but does correlate with the gap between the highest occupied and lowest unoccupied orbital energies in the mean-field calculation.

  18. Barriers and strategies for innovations entering BoP markets

    NARCIS (Netherlands)

    Kamp, L.M.; Ortt, J.R.; Harahap, B.

    2015-01-01

    Companies that bring a new product to the market or enter a new market with an existing product, come across a number of barriers that prevent large‐scale diffusion. In order to circumvent or remove these barriers, they can adopt alternative strategies. This paper looks into these barriers and

  19. Explaining and overcoming barriers to climate change adaptation

    NARCIS (Netherlands)

    Eisenack, K.; Moser, S.C.; Hoffmann, E.; Klein, R.J.T.; Oberlack, C.; Pechan, A.; Rotter, M.; Termeer, C.J.A.M.

    2014-01-01

    The concept of barriers is increasingly used to describe the obstacles that hinder the planning and implementation of climate change adaptation. The growing literature on barriers to adaptation reveals not only commonly reported barriers, but also conflicting evidence, and few explanations of why

  20. Barriers to and Facilitators of Health for Latina Undergraduate Students

    Science.gov (United States)

    Mount, Jill

    2015-01-01

    Latina undergraduate students' barriers and facilitators of health are examined: Barriers to psychological health--separating from family, pressure to succeed, and racism; Barriers to physical health--lacking health insurance, and discomfort using campus sports facilities; and Facilitators of psychological health--membership in Latina student…