Science.gov

Sample records for horizontal forward-facing step

  1. Flow and forced-convection heat transfer over forward-facing double steps (effects of step ratio)

    SciTech Connect

    Shakouchi, Toshihiko; Kajino, Itsuki

    1994-07-01

    The flow and heat transfer over a step (a forward- or backward-facing step) result in complicated flow conditions, such as a shear flow field, flow separation, and generation of vortices, and provide some interesting information that improves understanding of the heat transfer on the surface. This is a very frequent flow, and basic to various kinds of chemical equipment, fluid machinery, combustion furnaces, and IC-packages. Recently, there have been many studies on this flow situation by numerical analysis, measurement of mean and fluctuating velocities within the separation bubble using laser Doppler anemometer, and heat transfer analysis. A flow passage having two steps in tiers (forward- or backward-facing double steps) is also frequent, and it is very important to clarify the effects of each step on the flow and the heat-transfer characteristics. This however, has not yet been investigated. This study presents the results of an experimental investigation on the flow and forced convective heat transfer over forward-facing single and double steps. Measurements of velocity and turbulence intensity, flow visualization, pressure distribution, and heat transfer over forward-facing double steps were carried out for various step ratios, L/a (L: step length, a: step height). From these results, the effects of the step ratio on the flow and heat-transfer characteristics were clarified and the following results were confirmed. Heat-transfer enhancement of a double step is considerable compared with that of a single step or a flat plate.

  2. The Effect of Micro-ramps on Supersonic Flow over a Forward-Facing Step

    NASA Astrophysics Data System (ADS)

    Zhang, Qing-Hu; Yi, Shi-He; Zhu, Yang-Zhu; Chen, Zhi; Wu, Yu

    2013-04-01

    The effect of micro-ramp control on fully developed turbulent flow over a forward-facing step (FFS) is investigated in a supersonic low-noise wind tunnel at Mach number 3 using nano-tracer planar laser scattering (NPLS) and supersonic particle image velocimetry (PIV) techniques. High spatiotemporal resolution images and the average velocity profiles of supersonic flow over the FFS with and without the control of the micro-ramps are captured. The fine structures of both cases, including the coherent structures of fully developed boundary layer and the large-scale hairpin-like vortices originated from the micro-ramps as well as the interaction of shock waves with the large-scale structures, are revealed and compared. Based on the time-correlation images, the temporal and spatial evolutionary characteristics of the coherent structures are investigated. It is beneficial to understand the dynamic mechanisms of the separated flow and the control mechanisms of the micro-ramps. The size of the separation region is determined by the NPLS and PIV. The results indicate that the control of the micro-ramps is capable of delaying the separation and diminishing the extent of recirculation zone.

  3. Flow control of micro-ramps on supersonic forward-facing step flow

    NASA Astrophysics Data System (ADS)

    Qing-Hu, Zhang; Tao, Zhu; Shihe, Yi; Anping, Wu

    2016-05-01

    The effects of the micro-ramps on supersonic turbulent flow over a forward-facing step (FFS) was experimentally investigated in a supersonic low-noise wind tunnel at Mach number 3 using nano-tracer planar laser scattering (NPLS) and particle image velocimetry (PIV) techniques. High spatiotemporal resolution images and velocity fields of supersonic flow over the testing model were captured. The fine structures and their spatial evolutionary characteristics without and with the micro-ramps were revealed and compared. The large-scale structures generated by the micro-ramps can survive the downstream FFS flowfield. The micro-ramps control on the flow separation and the separation shock unsteadiness was investigated by PIV results. With the micro-ramps, the reduction in the range of the reversal flow zone in streamwise direction is 50% and the turbulence intensity is also reduced. Moreover, the reduction in the average separated region and in separation shock unsteadiness are 47% and 26%, respectively. The results indicate that the micro-ramps are effective in reducing the flow separation and the separation shock unsteadiness. Project supported by the National Natural Science Foundation of China (Grant Nos. 11172326 and 11502280).

  4. Beamforming of aeroacoustic sources in the time domain: An investigation of the intermittency of the noise radiated by a forward-facing step

    NASA Astrophysics Data System (ADS)

    Fischer, J.; Valeau, V.; Brizzi, L.-E.

    2016-11-01

    The present study investigates the intermittency of the broadband aeroacoustic noise produced by a forward-facing step in a flow. The noise source is viewed as a random succession of the so-called intermittent events of short duration distributed spatially in a source region in the flow. An array processing method based on time-domain beamforming has been developed in order to track systematically the intermittent events, both in the time and space domains. Based on a simulated model of the far-field pressure field, the method is validated in terms of event detection and of performance for recovering the pressure spectrum. The method is then applied to experimental array data taken in an anechoic wind-tunnel at low Mach numbers (not exceeding 0.15) for a forward-facing step of height 30 mm. The results show that some very short intermittent events (with a mean duration of the order of 0.15 ms) can be identified from the array data. The spatial distribution of the intermittent events is found to be in agreement with the frequency domain beamform maps. The probability density functions of the events, in terms of widths and apparition times, are shown to be governed by Gamma laws and indicate random phenomena; it is observed that the statistical distributions vary with the streamwise position downstream and upstream of the step, the trends being in agreement with the source behavior as evidenced by using the frequency-domain beamforming methods. The proposed method is then shown to identify, in terms of emission time, location and temporal width, a succession of short acoustic events that participate to the broadband aeroacoustic noise produced by the step; those random events are likely to be linked to the dynamics of the flow interacting with the step.

  5. Perceptual bias for forward-facing motion

    NASA Technical Reports Server (NTRS)

    Mcbeath, Michael K.; Morikawa, Kazunori; Kaiser, Mary K.

    1992-01-01

    When an occluded horizontal row of shapes is shifted laterally, apparent motion can be experienced in either the leftward or the rightward direction. Four experiments provide evidence for a motion bias in the direction that shapes appear to face. The bias tended to be largest when directionality was specified geometrically (e.g., triangles), next largest when it was specified biologically (e.g., mice), and absent when it was specified calligraphically (e.g., letter R). The bias increased parametrically as a function of triangle pointedness and was consistent with the directional interpretation of an ambiguous duck-rabbit. The results support the existence of a cognitively specified forward-facing attribute that can influence experienced direction of motion.

  6. Natural and orbital debris particles on LDEF's trailing and forward-facing surfaces

    NASA Technical Reports Server (NTRS)

    Hoerz, Friedrich; See, Thomas H.; Bernhard, Ronald P.; Brownlee, Donald E.

    1995-01-01

    Approximately 1000 impact craters on the Chemistry of Meteoroid Experiment (CME) have been analyzed by means of Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDXA) to determine the compositional make-up of projectile residues. This report completes our systematic survey of gold and aluminum surfaces exposed at the trailing-edge (A03) and forward-facing (A11) LDEF sites, respectively. The major categories for the projectile residues were (1) natural, with diverse subgroups such as chondritic, monomineralic silicates, and sulfides, and (2) man made, that were classified into aluminum (metallic or oxide) and miscellaneous materials (such as stainless steel, paint flakes, etc). On CME gold collectors on LDEF's trailing edge approximately 11 percent of all craters greater than 100 micron in diameter were due to man-made debris, the majority (8.6 percent) caused by pure aluminum, approximately 31.4 percent were due to cosmic dust, while the remaining 58 percent were indeterminate via the analytical techniques utilized in this study. The aluminum surfaces located at the A11 forward-facing site did not permit analysis of aluminum impactors, but approximately 9.4 percent of all craters were demonstratably caused by miscellaneous debris materials and approximately 39.2 percent were the result of natural particles, leaving approximately 50 percent which were indeterminate. Model considerations and calculations are presented that focus on the crater-production rates for features greater than 100 micron in diameter, and on assigning the intermediate crater population to man-made or natural particles. An enhancement factor of 6 in the crater-production rate of natural impactors for the 'forward-facing' versus the 'trailing-edge' CME collectors was found to best explain all observations (i.e., total crater number(s), as well as their computational characteristics). Enhancement factors of 10 and 4 are either too high or too low. It is also suggested that

  7. Pelvic step: the contribution of horizontal pelvis rotation to step length in young healthy adults walking on a treadmill.

    PubMed

    Liang, Bo Wei; Wu, Wen Hua; Meijer, Onno G; Lin, Jian Hua; Lv, Go Rong; Lin, Xiao Cong; Prins, Maarten R; Hu, Hai; van Dieën, Jaap H; Bruijn, Sjoerd M

    2014-01-01

    Transverse plane pelvis rotations during walking may be regarded as the "first determinant of gait". This would assume that pelvis rotations increase step length, and thereby reduce the vertical movements of the centre of mass-"the pelvic step". We analysed the pelvic step using 20 healthy young male subjects, walking on a treadmill at 1-5 km/h, with normal or big steps. Step length, pelvis rotation amplitude, leg-pelvis relative phase, and the contribution of pelvis rotation to step length were calculated. When speed increased in normal walking, pelvis rotation changed from more out-of-phase to in-phase with the upper leg. Consequently, the contribution of pelvis rotation to step length was negative at lower speeds, switching to positive at 3 km/h. With big steps, leg and pelvis were more in-phase, and the contribution of pelvis rotation to step length was always positive, and relatively large. Still, the overall contribution of pelvis rotations to step length was small, less than 3%. Regression analysis revealed that leg-pelvis relative phase predicted about 60% of the variance of this contribution. The results of the present study suggest that, during normal slow walking, pelvis rotations increase, rather than decrease, the vertical movements of the centre of mass. With large steps, this does not happen, because leg and pelvis are in-phase at all speeds. Finally, it has been suggested that patients with hip flexion limitation may use larger pelvis rotations to increase step length. This, however, may only work as long as the pelvis rotates in-phase with the leg.

  8. Influence of a step-change increase of peat moisture content on the horizontal propagation of smouldering fires

    NASA Astrophysics Data System (ADS)

    Prat-Guitart, Nuria; Belcher, Claire M.; Hadden, Rory M.; Rein, Guillermo; Yearsley, Jon M.

    2015-04-01

    In shallow layers of peat, the transition between moss species causes a step-change of the horizontal distribution of peat moisture content. Post-fire studies in peatlands have reported shallow layers being consumed in irregular distributions. The unburned areas were found to be patches of wet Sphagnum moss. Our laboratory scale study analyses the effect of a horizontal step-change in moisture content on the spread of smouldering. We designed a laboratory-scale experiment (20×18×5 cm) within an insulated box filled with milled peat. Peat was ignited on one side of the box from which the smouldering fire horizontally self-propagates through a region of dry peat (MC1) and then through a wetter region of peat (MC2). An infrared camera, a webcam and thermocouples monitor the position of the smouldering fire spreading horizontally. The experiment was repeated with peats at different moisture content combinations to analyse the smouldering behaviour on a range of moisture content step-change conditions. The data analysis estimates the burned area and examines smouldering fire behaviour across a wide range of moisture content combinations reproducing realistic scenarios. We found that the area burned depends on peat moisture content before the step-change (MC1) as well as the increase in moisture of the step-change itself (difference between MC1 and MC2). Our study assists in researching the influence of peat moisture content on the spread of smouldering in peatland fire and contributes to a better understanding of the post-fire peatland landscape, helping to reconstruct smouldering fire events.

  9. Frontal Sled Tests Comparing Rear and Forward Facing Child Restraints with 1–3 Year Old Dummies

    PubMed Central

    Sherwood, C. P.; Crandall, J. R.

    2007-01-01

    Although most countries recommend transitioning children from rear facing (RF) to forward facing (FF) child restraints at one year of age, Swedish data suggests that RF restraints are more effective. The objective of this study was to compare RF and FF orientations in frontal sled tests. Four dummies (CRABI 12mo, Q1.5, Hybrid III 3yr, and Q3) were used to represent children from 1 to 3 years of age. Restraint systems tested included both 1) LATCH and 2) rigid ISOFIX with support leg designs. Rear facing restraints with support legs provided the best results for all injury measures, while RF restraints in general provided the lowest chest displacements and neck loads. PMID:18184491

  10. Frontal sled tests comparing rear and forward facing child restraints with 1-3 year old dummies.

    PubMed

    Sherwood, C P; Crandall, J R

    2007-01-01

    Although most countries recommend transitioning children from rear facing (RF) to forward facing (FF) child restraints at one year of age, Swedish data suggests that RF restraints are more effective. The objective of this study was to compare RF and FF orientations in frontal sled tests. Four dummies (CRABI 12 mo, Q1.5, Hybrid III 3 yr, and Q3) were used to represent children from 1 to 3 years of age. Restraint systems tested included both 1) LATCH and 2) rigid ISOFIX with support leg designs. Rear facing restraints with support legs provided the best results for all injury measures, while RF restraints in general provided the lowest chest displacements and neck loads.

  11. Teaching Activities on Horizontal Nuclear Proliferation.

    ERIC Educational Resources Information Center

    Zola, John

    1990-01-01

    Provides learning activities concerning the horizontal proliferation of nuclear weapons. Includes step-by-step directions for four activities: (1) the life cycle of nuclear weapons; (2) nuclear nonproliferation: pros and cons; (3) the nuclear power/nuclear weapons connection; and (4) managing nuclear proliferation. (NL)

  12. Horizontal drilling developments

    SciTech Connect

    Gust, D.

    1997-05-01

    The advantages of horizontal drilling are discussed. Use of horizontal drilling has climbed in the past half decade as technology and familiarity offset higher costs with higher production rates and greater recoveries from new and existing wells. In essence, all types of horizontal wells expose a larger section of the reservoir to the wellbore with a resulting increase in flow rates. (A horizontal well may also be drilled to provide coning control or to intersect vertical fractures.) Thus, drilling horizontally, both onshore and offshore, reduces the number of wells necessary to develop a field.

  13. Anomalous rectification in horizontal cells.

    PubMed Central

    Werblin, F S

    1975-01-01

    1. The electrical properties of horizontal cells in the mudpuppy in light and dark were measured with a pair of micropipettes separated by about 1 mum with low coupling resistance so that no bridge circuitry was required. 2. All horizontal cells studied showed significant anomalous rectification: the current-voltage characteristic for about 60 per cent of the cells studied had a slope resistance of about 20-30 M omega at the dark potential level; the slope resistance increased by about 15% for each 10 mV depolarization and decreased by about 15% for each 10 mV hyperpolarization. The remaining 40% of the horizontal cells showed a higher input resistance at corresponding potential levels but had similar rectifying properties. 3. The increase in resistance with depolrization developed with a time course of about 1/2 sec when steady steps of outward current were passed across the membrane, but the time course for resistance decrease with hyperpolarization was much shorter for steady inward current steps. In about half the horizontal cells there was a transient decrease in resistance lasting about 100 msec immediately following the outward current steps superimposed upon the slower sustained resistance increase. 4. The normal 20-30 mV hyperpolarizing light response was associated with little or no change in input resistance. However, if the membrane potential was held at the dark potential level with extrinsic current, thereby eliminating the potential-dependent resistance change, a light-elicited resistance increase of about 10 M omega was measured. 5. The time-dependent change in membrane resistance elicited by polarizing steps of current obscured the reversal potential for the response. However, when the reversal potential was measured at short times following polarization of the membrane, before the time-dependent resistance change developed, it was estimated at between +15 and +50 m V. 6. The results suggest that the horizontal cell response is mediated by a light

  14. Security: Step by Step

    ERIC Educational Resources Information Center

    Svetcov, Eric

    2005-01-01

    This article provides a list of the essential steps to keeping a school's or district's network safe and sound. It describes how to establish a security architecture and approach that will continually evolve as the threat environment changes over time. The article discusses the methodology for implementing this approach and then discusses the…

  15. Effects of Forward- and Backward-Facing Steps on the Crossflow Receptivity and Stability in Supersonic Boundary Layers

    NASA Technical Reports Server (NTRS)

    Balakumar, P.; King, Rudolph A.; Eppink, Jenna L.

    2014-01-01

    The effects of forward- and backward-facing steps on the receptivity and stability of three-dimensional supersonic boundary layers over a swept wing with a blunt leading edge are numerically investigated for a freestream Mach number of 3 and a sweep angle of 30 degrees. The flow fields are obtained by solving the full Navier-Stokes equations. The evolution of instability waves generated by surface roughness is simulated with and without the forward- and backward-facing steps. The separation bubble lengths are about 5-10 step heights for the forward-facing step and are about 10 for the backward-facing step. The linear stability calculations show very strong instability in the separated region with a large frequency domain. The simulation results show that the presence of backward-facing steps decreases the amplitude of the stationary crossflow vortices with longer spanwise wavelengths by about fifty percent and the presence of forward-facing steps does not modify the amplitudes noticeably across the steps. The waves with the shorter wavelengths grow substantially downstream of the step in agreement with the linear stability prediction.

  16. Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Detail, Vertical Cross Bracing-End Detail - Cumberland Covered Bridge, Spanning Mississinewa River, Matthews, Grant County, IN

  17. Next Step for STEP

    SciTech Connect

    Wood, Claire; Bremner, Brenda

    2013-08-09

    The Siletz Tribal Energy Program (STEP), housed in the Tribe’s Planning Department, will hire a data entry coordinator to collect, enter, analyze and store all the current and future energy efficiency and renewable energy data pertaining to administrative structures the tribe owns and operates and for homes in which tribal members live. The proposed data entry coordinator will conduct an energy options analysis in collaboration with the rest of the Siletz Tribal Energy Program and Planning Department staff. An energy options analysis will result in a thorough understanding of tribal energy resources and consumption, if energy efficiency and conservation measures being implemented are having the desired effect, analysis of tribal energy loads (current and future energy consumption), and evaluation of local and commercial energy supply options. A literature search will also be conducted. In order to educate additional tribal members about renewable energy, we will send four tribal members to be trained to install and maintain solar panels, solar hot water heaters, wind turbines and/or micro-hydro.

  18. Horizontal carbon nanotube alignment.

    PubMed

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

    2016-09-21

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

  19. Horizontal carbon nanotube alignment.

    PubMed

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

    2016-09-21

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

  20. Horizontal Advanced Tensiometer

    SciTech Connect

    Hubbell, Joel M.; Sisson, James B.

    2004-06-22

    An horizontal advanced tensiometer is described that allows the monitoring of the water pressure of soil positions, particularly beneath objects or materials that inhibit the use of previous monitoring wells. The tensiometer includes a porous cup, a pressure transducer (with an attached gasket device), an adaptive chamber, at least one outer guide tube which allows access to the desired horizontal position, a transducer wire, a data logger and preferably an inner guide tube and a specialized joint which provides pressure on the inner guide tube to maintain the seal between the gasket of the transducer and the adaptive chamber.

  1. Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Joint, Vertical Cross Bracing End Detail - Ceylon Covered Bridge, Limberlost Park, spanning Wabash River at County Road 900 South, Geneva, Adams County, IN

  2. High-torque precision stepping drive

    NASA Technical Reports Server (NTRS)

    Kaspareck, W. E.

    1968-01-01

    Stepping drive has been designed for precise incremental angular positioning of scale models of spacecraft about a horizontal axis in order to accurately measure antenna receiving and transmitting characteristics. Positioning is insured by spring-loaded, self-locking plungers.

  3. Horizontally mounted solar collector

    NASA Technical Reports Server (NTRS)

    Black, D. H. (Inventor)

    1979-01-01

    Solar energy is collected by using a vertical deflector assembly, a stationary reflector and a horizontally mounted solar collector. The deflector assembly contains a plurality of vanes which change the direction of the solar energy to the vertical, while constantly keeping the same side of the deflector facing the sun. The vertical rays are then reflected off the stationary reflector and are then absorbed by the collector.

  4. Horizontal branch evolution

    NASA Astrophysics Data System (ADS)

    Rood, R. T.; Crocker, D. A.

    In 1973 the outstanding problems confronting the theory of horizontal-branch (HB) evolution were the second-parameter problem and the Oosterhoff effect. Despite significant progress, particularly in the observations and in the observation/theory interface, they remain as the outstanding problems of 1988. The Oosterhoff effect is now discussed primarily in the guise of the Sandage period-shift effect. The morphology of the HB seems more complicated than ever. Many clusters show bimodal distributions along the HB. Here these are tentatively considered to be manifestations of the second parameter problem.

  5. Horizontal baffle for nuclear reactors

    DOEpatents

    Rylatt, John A.

    1978-01-01

    A horizontal baffle disposed in the annulus defined between the core barrel and the thermal liner of a nuclear reactor thereby physically separating the outlet region of the core from the annular area below the horizontal baffle. The horizontal baffle prevents hot coolant that has passed through the reactor core from thermally damaging apparatus located in the annulus below the horizontal baffle by utilizing the thermally induced bowing of the horizontal baffle to enhance sealing while accommodating lateral motion of the baffle base plate.

  6. Horizontal SPINning of transposons.

    PubMed

    Gilbert, Clément; Pace, John K; Feschotte, Cédric

    2009-01-01

    The term 'horizontal transfer (HT)' refers to the transfer of genetic material between two reproductively isolated organisms. HT is thought to occur rarely in eukaryotes compared to vertical inheritance, the transmission of DNA from parent to offspring. In a recent study we have provided evidence that a family of DNA transposons, called SPACE INVADERS or SPIN, independently invaded horizontally the genome of seven distantly related tetrapod species and subsequently amplified to high copy number in each of them. This discovery calls for further investigations to better characterize the extent to which genomes have been shaped through HT events. In this addendum, we briefly discuss some general issues regarding the study of HT and further speculate on the sequence of events that could explain the current taxonomic distribution of SPIN. We propose that the presence of SPIN in the opossum (Monodelphis domestica), a taxon endemic to South America, reflects a transoceanic HT event that occurred from Old to New World, between 46 and 15 million years ago.

  7. Orthodontic extrusion of horizontally impacted mandibular molars

    PubMed Central

    Ma, Zhigui; Yang, Chi; Zhang, Shanyong; Xie, Qianyang; Shen, Yuqing; Shen, Pei

    2014-01-01

    Objective: To introduce and evaluate a novel approach in treating horizontally impacted mandibular second and third molars. Materials and methods: An orthodontic technique was applied for treatment of horizontally impacted mandibular second and third molars, which included a push-type spring for rotation first, and then a cantilever for extrusion. There were 8 mandibular third molars (M3s) and 2 second molars (M2s) in this study. Tooth mobility, extraction time, the inclination and parallelism of the impacted tooth, alveolar bone height of the adjacent tooth, and the relationship of impacted M3 and the inferior alveolar nerve (IAN) were evaluated. Results: Two horizontally impacted M2s could be upright in the arch and good occlusal relationships were obtained after treatment. All impacted M3s were successfully separated from the IAN, without any neurologic consequences. The average extraction time was 5 minutes. There was a significant change in the inclination and parallelism of the impacted tooth after treatment. A new bone apposition with the average height of 3.2 mm was noted distal to the adjacent tooth. Conclusions: This two-step orthodontic technique as presented here may be a safe and feasible alternative in management of severely horizontally impacted mandibular molars, which achieves a successful separation of M3s from the IAN and an excellent position for M2s. PMID:25419364

  8. PHOEBE - step by step manual

    NASA Astrophysics Data System (ADS)

    Zasche, P.

    2016-03-01

    An easy step-by-step manual of PHOEBE is presented. It should serve as a starting point for the first time users of PHOEBE analyzing the eclipsing binary light curve. It is demonstrated on one particular detached system also with the downloadable data and the whole procedure is described easily till the final trustworthy fit is being reached.

  9. Horizontal axis windmill

    SciTech Connect

    Mundhenke, I.W.

    1984-05-22

    A base frame supports a horizontal shaft having one or more wind driven members secured thereon. Each of the wind driven members includes a shaft of light-weight framing and plurality of elongated longitudinally extending light-weight vanes having wind engaging surfaces. The vanes have a wind driving position on one side of the shaft and a return position of the other, and light-weight wind deflectors disposed at the front of the frame protecting the return position of the vanes from the wind. The wind deflectors are angularly adjustable whereby the deflected wind flowing off the longitudinal edges thereof is selectively directed against the vane surfaces in their driving position. The shaft has an output for operating a selected driven apparatus such as a generator. The base frame is rotatably supported on a pivot for selected adjustment relative to the wind.

  10. HORIZONTAL BOILING REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  11. Horizontally shaken impact pendulums

    NASA Astrophysics Data System (ADS)

    Alexander, T. J.; Xu, Y.; Sidhu, H.

    2016-03-01

    We consider two pendulum masses attached to the same pivot point and which interact with each other through Hertzian impacts. We show that this splitting of the mass leads to an instability in the conservative case, in which initially synchronized large amplitude motion may evolve into out-of-phase (impacting) motion. We then study in detail the response of the impacting masses in the presence of damping and driving through horizontal shaking of the pivot point. We find that synchronized modes are usually accompanied by small amplitude quasi-periodic, or even chaotic, impacts and a number of multi-period solutions may appear in the bifurcation diagram. We reveal the existence and stability of a number of impact modes and scan the frequency response of the system to a series of initial conditions to identify which modes may be more easily generated in experiment.

  12. Inferring horizontal gene transfer.

    PubMed

    Ravenhall, Matt; Škunca, Nives; Lassalle, Florent; Dessimoz, Christophe

    2015-05-01

    Horizontal or Lateral Gene Transfer (HGT or LGT) is the transmission of portions of genomic DNA between organisms through a process decoupled from vertical inheritance. In the presence of HGT events, different fragments of the genome are the result of different evolutionary histories. This can therefore complicate the investigations of evolutionary relatedness of lineages and species. Also, as HGT can bring into genomes radically different genotypes from distant lineages, or even new genes bearing new functions, it is a major source of phenotypic innovation and a mechanism of niche adaptation. For example, of particular relevance to human health is the lateral transfer of antibiotic resistance and pathogenicity determinants, leading to the emergence of pathogenic lineages. Computational identification of HGT events relies upon the investigation of sequence composition or evolutionary history of genes. Sequence composition-based ("parametric") methods search for deviations from the genomic average, whereas evolutionary history-based ("phylogenetic") approaches identify genes whose evolutionary history significantly differs from that of the host species. The evaluation and benchmarking of HGT inference methods typically rely upon simulated genomes, for which the true history is known. On real data, different methods tend to infer different HGT events, and as a result it can be difficult to ascertain all but simple and clear-cut HGT events. PMID:26020646

  13. Inferring Horizontal Gene Transfer

    PubMed Central

    Lassalle, Florent; Dessimoz, Christophe

    2015-01-01

    Horizontal or Lateral Gene Transfer (HGT or LGT) is the transmission of portions of genomic DNA between organisms through a process decoupled from vertical inheritance. In the presence of HGT events, different fragments of the genome are the result of different evolutionary histories. This can therefore complicate the investigations of evolutionary relatedness of lineages and species. Also, as HGT can bring into genomes radically different genotypes from distant lineages, or even new genes bearing new functions, it is a major source of phenotypic innovation and a mechanism of niche adaptation. For example, of particular relevance to human health is the lateral transfer of antibiotic resistance and pathogenicity determinants, leading to the emergence of pathogenic lineages [1]. Computational identification of HGT events relies upon the investigation of sequence composition or evolutionary history of genes. Sequence composition-based ("parametric") methods search for deviations from the genomic average, whereas evolutionary history-based ("phylogenetic") approaches identify genes whose evolutionary history significantly differs from that of the host species. The evaluation and benchmarking of HGT inference methods typically rely upon simulated genomes, for which the true history is known. On real data, different methods tend to infer different HGT events, and as a result it can be difficult to ascertain all but simple and clear-cut HGT events. PMID:26020646

  14. Understanding Horizontal Governance. Research Brief

    ERIC Educational Resources Information Center

    Ferguson, Daniel

    2009-01-01

    Horizontal governance is an umbrella term that covers a range of approaches to policy development, service delivery issues, and management practices. A horizontal initiative may take place across levels of government, across boundaries between units of a single department or agency or among multiple departments or agencies, or across public,…

  15. Nurse Against Nurse: Horizontal Bullying in the Nursing Profession.

    PubMed

    Granstra, Katherine

    2015-01-01

    Healthcare professionals are not immune to bullying; in fact, they experience bullying at an alarming rate. Sometimes the bullying is passed down from superiors, but frequently bullying occurs between coworkers. This is known as "horizontal bullying," and it has become a serious issue within the nursing profession. Horizontal bullying between nurses can cause negative consequences for everyone involved, in particular the nurses, patients, and the entire organization. To fully address and resolve horizontal bullying in the nursing profession, we must consider many factors. The first step is to establish what constitutes bullying and to develop a clear process for dealing with it when it occurs. Before it is possible to eliminate the problem, we need to understand why bullying takes place. To be effective, solutions to the problem of horizontal bullying in the nursing profession must include the entire healthcare industry.

  16. Horizontal and Vertical Line Designs.

    ERIC Educational Resources Information Center

    Johns, Pat

    2003-01-01

    Presents an art lesson in which students learn about the artist Piet Mondrian and create their own abstract artworks. Focuses on geometric shapes using horizontal and vertical lines. Includes background information about the artist. (CMK)

  17. Stepped nozzle

    DOEpatents

    Sutton, George P.

    1998-01-01

    An insert which allows a supersonic nozzle of a rocket propulsion system to operate at two or more different nozzle area ratios. This provides an improved vehicle flight performance or increased payload. The insert has significant advantages over existing devices for increasing nozzle area ratios. The insert is temporarily fastened by a simple retaining mechanism to the aft end of the diverging segment of the nozzle and provides for a multi-step variation of nozzle area ratio. When mounted in place, the insert provides the nozzle with a low nozzle area ratio. During flight, the retaining mechanism is released and the insert ejected thereby providing a high nozzle area ratio in the diverging nozzle segment.

  18. Stepped nozzle

    DOEpatents

    Sutton, G.P.

    1998-07-14

    An insert is described which allows a supersonic nozzle of a rocket propulsion system to operate at two or more different nozzle area ratios. This provides an improved vehicle flight performance or increased payload. The insert has significant advantages over existing devices for increasing nozzle area ratios. The insert is temporarily fastened by a simple retaining mechanism to the aft end of the diverging segment of the nozzle and provides for a multi-step variation of nozzle area ratio. When mounted in place, the insert provides the nozzle with a low nozzle area ratio. During flight, the retaining mechanism is released and the insert ejected thereby providing a high nozzle area ratio in the diverging nozzle segment. 5 figs.

  19. Nuclear component horizontal seismic restraint

    DOEpatents

    Snyder, Glenn J.

    1988-01-01

    A nuclear component horizontal seismic restraint. Small gaps limit horizontal displacement of components during a seismic occurrence and therefore reduce dynamic loadings on the free lower end. The reactor vessel and reactor guard vessel use thicker section roll-forged rings welded between the vessel straight shell sections and the bottom hemispherical head sections. The inside of the reactor guard vessel ring forging contains local vertical dovetail slots and upper ledge pockets to mount and retain field fitted and installed blocks. As an option, the horizontal displacement of the reactor vessel core support cone can be limited by including shop fitted/installed local blocks in opposing alignment with the reactor vessel forged ring. Beams embedded in the wall of the reactor building protrude into apertures in the thermal insulation shell adjacent the reactor guard vessel ring and have motion limit blocks attached thereto to provide to a predetermined clearance between the blocks and reactor guard vessel ring.

  20. Speckle Imaging Over Horizontal Paths

    SciTech Connect

    Carrano, C J

    2002-05-21

    Atmospheric aberrations reduce the resolution and contrast in surveillance images recorded over horizontal or slant paths. This paper describes our recent horizontal and slant path imaging experiments of extended scenes as well as the results obtained using speckle imaging. The experiments were performed with an 8-inch diameter telescope placed on either a rooftop or hillside and cover ranges of interest from 0.5 km up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures. The improvement in image quality using speckle imaging is dramatic in many cases, and depends significantly upon the atmospheric conditions. We quantify resolution improvement through modulation transfer function measurement comparisons.

  1. Success in horizontal barrier developments

    SciTech Connect

    Pettit, P.J.; Ridenour, D.E.; Jalovec, J.

    1996-06-01

    A successful proof of concept demonstration has been conducted of operational methods and tooling for the in situ construction of underground horizontal barriers for the control and containment of groundwater and contamination. The method involves jet grouting with specially adapted tools guided between twin, parallel wells for the placement of a grout beneath a waste site. The objective of the work is to develop reliable methods of constructing extensive, competent horizontal barriers underneath waste sites without excavating or penetrating the waste during the process.

  2. Horizontal electric fields from lightning return strokes

    NASA Technical Reports Server (NTRS)

    Thomson, E. M.; Medelius, P. J.; Rubinstein, M.; Uman, M. A.; Johnson, J.

    1988-01-01

    An experiment to measure simultaneously the wideband horizontal and vertical electric fields from lightning return strokes is described. Typical wave shapes of the measured horizontal and vertical fields are presented, and the horizontal fields are characterized. The measured horizontal fields are compared with calculated horizontal fields obtained by applying the wavetilt formula to the vertical fields. The limitations and sources of error in the measurement technique are discussed.

  3. Theoretical horizontal-branch evolution

    NASA Technical Reports Server (NTRS)

    Sweigart, Allen V.

    1987-01-01

    The general features of the theoretical evolution of canonical horizontal-branch (HB) stars are briefly reviewed with specific emphasis on the track morphology in the HR diagram and the determination of the globular cluster helium abundance. The observational evidence for the occurrence of semiconvection is discussed together with some remaining theoretical uncertainty.

  4. Horizontal drilling installs dutch waterline

    SciTech Connect

    Not Available

    1986-08-01

    A 32-in. potable water line system, installed by Van Eijk Leidingen B.V. in Holland, was laid through an intensively cultivated vegetable gardening area, and designed to furnish additional irrigation water. Using a horizontally drilled 42-in. hole under the Maasdijk, though a difficult job, reduced the length by more than 3 miles.

  5. Dragging a floating horizontal cylinder

    NASA Astrophysics Data System (ADS)

    Lee, Duck-Gyu; Kim, Ho-Young

    2010-11-01

    A cylinder immersed in a fluid stream experiences a drag, and it is well known that the drag coefficient is a function of the Reynolds number only. Here we study the force exerted on a long horizontal cylinder that is dragged perpendicular to its axis while floating on an air-water interface with a high Reynolds number. In addition to the flow-induced drag, the floating body is subjected to capillary forces along the contact line where the three phases of liquid/solid/gas meet. We first theoretically predict the meniscus profile around the horizontally moving cylinder assuming the potential flow, and show that the profile is in good agreement with that obtained experimentally. Then we compare our theoretical predictions and experimental measurement results for the drag coefficient of a floating horizontal cylinder that is given by a function of the Weber number and the Bond number. This study can help us to understand the horizontal motion of partially submerged objects at air-liquid interface, such as semi-aquatic insects and marine plants.

  6. Some Considerations on Horizontal Displacement and Horizontal Displacement Coefficient B

    NASA Astrophysics Data System (ADS)

    Tajduś, Krzysztof; Tajduś, Antoni

    2015-12-01

    Mining-induced deformations of the ground surface and within the rock mass may pose danger not only for surface constructions but also for underground objects (e.g., tunnels, underground storages, garages), diverse types of pipelines, electric cables, etc. For a proper evaluation of hazard for surface and underground objects, such parameters as horizontal displacement and horizontal deformations, especially their maximum values, are of crucial importance. The paper is an attempt at a critical review of hitherto accomplished studies and state of the art of predicting horizontal displacement u, in particular the coefficient B, whose value allows determination of the value of maximum displacement if the value of maximum slope is known, or the value of maximum deformation if the value of maximum trough slope is recognized. Since the geodesic observations of fully developed subsidence troughs suggest that the value of the coefficient depends on the depth H, radius of main influences range r and properties of overburden rock, in particular the occurrence of sub-eras Paleogene and Neogene layers (old name: Quaternary and Tertiary) with low strength parameters, therefore a formula is provided in the present paper allowing for the estimation of the influence of those factors on the value of coefficient B.

  7. Synaptic Transmission from Horizontal Cells to Cones Is Impaired by Loss of Connexin Hemichannels

    PubMed Central

    Klaassen, Lauw J.; Sun, Ziyi; Steijaert, Marvin N.; Bolte, Petra; Fahrenfort, Iris; Sjoerdsma, Trijntje; Klooster, Jan; Claassen, Yvonne; Shields, Colleen R.; Ten Eikelder, Huub M. M.; Janssen-Bienhold, Ulrike; Zoidl, Georg; McMahon, Douglas G.; Kamermans, Maarten

    2011-01-01

    In the vertebrate retina, horizontal cells generate the inhibitory surround of bipolar cells, an essential step in contrast enhancement. For the last decades, the mechanism involved in this inhibitory synaptic pathway has been a major controversy in retinal research. One hypothesis suggests that connexin hemichannels mediate this negative feedback signal; another suggests that feedback is mediated by protons. Mutant zebrafish were generated that lack connexin 55.5 hemichannels in horizontal cells. Whole cell voltage clamp recordings were made from isolated horizontal cells and cones in flat mount retinas. Light-induced feedback from horizontal cells to cones was reduced in mutants. A reduction of feedback was also found when horizontal cells were pharmacologically hyperpolarized but was absent when they were pharmacologically depolarized. Hemichannel currents in isolated horizontal cells showed a similar behavior. The hyperpolarization-induced hemichannel current was strongly reduced in the mutants while the depolarization-induced hemichannel current was not. Intracellular recordings were made from horizontal cells. Consistent with impaired feedback in the mutant, spectral opponent responses in horizontal cells were diminished in these animals. A behavioral assay revealed a lower contrast-sensitivity, illustrating the role of the horizontal cell to cone feedback pathway in contrast enhancement. Model simulations showed that the observed modifications of feedback can be accounted for by an ephaptic mechanism. A model for feedback, in which the number of connexin hemichannels is reduced to about 40%, fully predicts the specific asymmetric modification of feedback. To our knowledge, this is the first successful genetic interference in the feedback pathway from horizontal cells to cones. It provides direct evidence for an unconventional role of connexin hemichannels in the inhibitory synapse between horizontal cells and cones. This is an important step in resolving a

  8. Horizontal drilling opportunities in Ohio

    SciTech Connect

    Noel, J.A. )

    1991-08-01

    Horizontal drilling has become commonplace in certain parts of Texas. The Austin Chalk is the favorite target, especially where fracture systems are present. The activity has become so intense that leases are now costly or nearly impossible to find. This type of activity was prevalent during the late oil boom, but with vertical wells. So, the same areas that were drilled then are being redone with horizontal drilling. In the past few months, carbonates with little or no evidence of fracture systems are being drilled with some success. Because of the difficulty in lease acquisition, operators are turning their attention elsewhere. Even though horizontal drilling has been conducted limitedly in the Devonian black shales, the Appalachian basin is an area that calls for attention. In Ohio, there have been instances of discoveries of one-well fields in both the Trenton and Trempealeau formations. The initial production from these wells ranges from a few to hundreds of barrels of oil per day. The lack of success in offset wells has been attributed to the interpretation that the producing wells were serendipitously drilled into a limited fractured reservoir. In most cases, the producer is surrounded by clusters of dry holes. These Ohio wells and wells in one other area are studied using well data, spectral and sonic logs, aerial photographs, side-looking radar surveys, and other data. The results are presented on structure contour and lineament maps, and quantitative log interpretations. The maps show the interpretations of those areas of fracture systems that might be viable targets for horizontal drilling.

  9. Horizontal-branch stellar evolution

    NASA Technical Reports Server (NTRS)

    Sweigart, Allen V.

    1990-01-01

    The results of canonical theory for the evolution of horizontal-branch (HB) stars are examined. Particular attention is given to how an HB star maintains the appropriate composition distribution within the semiconvective zone and how this composition is affected by the finite time-dependence with which convective boundaries actually move. Newly developed models based on time-dependent overshooting are presented for both the core-helium-exhaustion and main HB phases.

  10. Remediation using nested, horizontal wells

    SciTech Connect

    Desantis, P.J.; Andrilenas, J.S.; Cheng, S.; Esler, C.; Miller, R.S.; Lew, K.V.

    1995-11-01

    A pair of nested, horizontal wells (one for vapor extraction, one for groundwater extraction) were utilized to remediate a mixed aromatic volatile organic compound (AVOC) and halogenated volatile organic compound (HVOC) soil and groundwater plume. The project site is an operating gasoline service station located in Portland, Oregon. The site has low permeability soils, a thin unconfined aquifer, with a relatively steep groundwater gradient. Each of the nested horizontal wells was drilled using the continuous borehole directional drilling method. The wells are each 110 meters long employing 73 meters of pre-packed well screen. The groundwater extraction well was pumped via vacuum-enhanced methods utilizing a two-pump configuration to eliminate the need for installation of a pump within the horizontal well and to increase both flow and radius of influence in fine-grained soils. Two groundwater models, a 2D analytical model and a finite element model, were utilized to analyze the potential and actual performance of the well. Of the two models used, the finite element model has produced results closely matching the actual performance of the well. After one year of operation, both AVOCs and HVOCs concentrations have been reduced by between 70 to 100%. All but two downgradient site wells have met cleanup standards for AVOCs; all have met substantial compliance for HVOCs.

  11. Industry survey for horizontal wells. Final report

    SciTech Connect

    Wilson, D.D.; Kaback, D.S.; Denhan, M.E.; Watkins, D.

    1993-07-01

    An international survey of horizontal environmental wells was performed during May and June of 1993. The purpose of the survey was to provide the environmental industry with an inventory of horizontal environmental wells and information pertaining to the extent of the use of horizontal environmental wells, the variety of horizontal environmental well applications, the types of geologic and hydrogeologic conditions within which horizontal environmental wells have been installed, and the companies that perform horizontal environmental well installations. Other information, such as the cost of horizontal environmental well installations and the results of tests performed on the wells, is not complete but is provided as general information with the caveat that the information should not be used to compare drilling companies. The result of the survey is a catalogue of horizontal environmental wells that are categorized by the objective or use of the wells, the vertical depth of the wells, and the drilling company contracted to install the wells.

  12. Portable Horizontal-Drilling And Positioning Device

    NASA Technical Reports Server (NTRS)

    Smigocki, Edmund; Johnson, Clarence

    1988-01-01

    Portable horizontal-drilling and positioning device, constructed mainly of off-the-shelf components, accurately drills horizontal small holes in irregularly shaped objects. Holes precisely placed and drilled in objects that cannot be moved to shop area. New device provides three axes of movement while maintaining horizontal drilling.

  13. Neonatal Stepping in Relation to Terrestrial Optic Flow

    ERIC Educational Resources Information Center

    Barbu-Roth, Marianne; Anderson, David I.; Despres, Adeline; Provasi, Joelle; Cabrol, Dominique; Campos, Joseph J.

    2009-01-01

    This experiment examined whether newborn stepping, a primitive form of bipedal locomotion, could be modulated by optical flow. Forty-eight 3-day-old infants were exposed to optical flows that were projected onto a horizontal surface above which the infants were suspended. Significantly more air steps were elicited by exposure to a terrestrial…

  14. Panspermia and horizontal gene transfer

    NASA Astrophysics Data System (ADS)

    Klyce, Brig

    2009-08-01

    Evidence that extremophiles are hardy and ubiquitous is helping to make panspermia a respectable theory. But even if life on Earth originally came from space, biologists assume that the subsequent evolution of life is still governed by the darwinian paradigm. In this review we show how panspermia could amend darwinism and point to a cosmic source for, not only extremophiles but, all of life. This version of panspermia can be called "strong panspermia." To support this theory we will discuss recent evidence pertaining to horizontal gene transfer, viruses, genes apparently older than the Earthly evolution of the features they encode, and primate-specific genes without identifiable precursors.

  15. Orphan penumbrae: Submerging horizontal fields

    NASA Astrophysics Data System (ADS)

    Jurčák, J.; Bellot Rubio, L. R.; Sobotka, M.

    2014-04-01

    Aims: We investigate the properties of orphan penumbrae, which are photospheric filamentary structures observed in active regions near polarity inversion lines that resemble the penumbra of regular sunspots but are not connected to any umbra. Methods: We use Hinode data from the Solar Optical Telescope to determine the properties of orphan penumbrae. Spectropolarimetric data are employed to obtain the vector magnetic field and line-of-sight velocities in the photosphere. Magnetograms are used to study the overall evolution of these structures, and G-band and Ca ii H filtergrams are to investigate their brightness and apparent horizontal motions. Results: Orphan penumbrae form between regions of opposite polarity in places with horizontal magnetic fields. Their magnetic configuration is that of Ω-shaped flux ropes. In the two cases studied here, the opposite-polarity regions approach each other with time and the whole structure submerges as the penumbral filaments disappear. Orphan penumbrae are very similar to regular penumbrae, including the existence of strong gas flows. Therefore, they could have a similar origin. The main difference between them is the absence of a "background" magnetic field in orphan penumbrae. This could explain most of the observed differences. Conclusions: The fast flows we detect in orphan penumbrae may be caused by the siphon flow mechanism. Based on the similarities between orphan and regular penumbrae, we propose that the Evershed flow is also a manifestation of siphon flows. A movie attached to Fig. 11 is available in electronic form at http://www.aanda.org

  16. Task specific adaptations in rat locomotion: runway versus horizontal ladder.

    PubMed

    Bolton, David A E; Tse, Arthur D Y; Ballermann, Mark; Misiaszek, John E; Fouad, Karim

    2006-04-01

    In walking quadrupeds the alternating activity pattern of antagonistic leg muscles and the coordination between legs is orchestrated by central pattern generating networks within the spinal cord. These networks are activated by tonic input from the reticular formation in the brainstem. Under more challenging conditions, such as walking on a horizontal ladder, successful locomotion relies upon additional context dependent input from pathways such as the cortico- and rubro-spinal tracts. In this study we used electromyographic and kinematic approaches to characterize the adaptations in the walking pattern in adult uninjured rats crossing a horizontal ladder. We found that the placement of a hind limb on a rung precisely followed the placement of the ipsilateral fore limb. This is different to normal walking where the hind limb is placed behind the position of the ipsilateral fore limb. The increased reach of the hind limbs is achieved by increased flexion of the hip and rotation of the pelvis during the swing phase. Electromyographic observations showed decreased burst duration in Tibialis anterior an ankle flexor muscle. Further changes in the muscle activity pattern were likely due to the reduced stepping frequency during ladder walking. Following a lesion of the dorsal column, containing major parts of the corticospinal tract, we found an increased number of stepping errors and changes in the stepping strategy. The step length of the fore limbs was reduced and the hind limbs were frequently positioned on rungs other than those occupied by the fore limb. PMID:16406145

  17. Explorando nuevos horizontes en NASA

    NASA Astrophysics Data System (ADS)

    Villanueva, G. L.

    A pesar de la incesante expansión del Universo iniciada con el Big Bang 14 mil millones de años atrás, nuestro Universo se siente cada día más cercano. La inquebrantable vocación de la humanidad por descubrir nuevos horizontes ha permitido el acercamiento de civilizaciones en nuestro planeta y nos ha permitido conocer nuestro lugar en el Universo como nunca antes. En este artículo presento una breve sinopsis de nuestro trabajo que se relaciona con diversas investigaciones con implicaciones astrobiológicas, desde el origen de los ingredientes de la "sopa de la vida", hasta la evolución y composición de la atmósfera de Marte.

  18. Horizontal gene transfer in choanoflagellates.

    PubMed

    Tucker, Richard P

    2013-01-01

    Horizontal gene transfer (HGT), also known as lateral gene transfer, results in the rapid acquisition of genes from another organism. HGT has long been known to be a driving force in speciation in prokaryotes, and there is evidence for HGT from symbiotic and infectious bacteria to metazoans, as well as from protists to bacteria. Recently, it has become clear that as many as a 1,000 genes in the genome of the choanoflagellate Monosiga brevicollis may have been acquired by HGT. Interestingly, these genes reportedly come from algae, bacteria, and other choanoflagellate prey. Some of these genes appear to have allowed an ancestral choanoflagellate to exploit nutrient-poor environments and were not passed on to metazoan descendents. However, some of these genes are also found in animal genomes, suggesting that HGT into a common ancestor of choanozoans and animals may have contributed to metazoan evolution.

  19. Horizontal high speed stacking for batteries with prismatic cans

    DOEpatents

    Bartos, Andrew L.; Lin, Yhu-Tin; Turner, III, Raymond D.

    2016-06-14

    A system and method for stacking battery cells or related assembled components. Generally planar, rectangular (prismatic-shaped) battery cells are moved from an as-received generally vertical stacking orientation to a generally horizontal stacking orientation without the need for robotic pick-and-place equipment. The system includes numerous conveyor belts that work in cooperation with one another to deliver, rotate and stack the cells or their affiliated assemblies. The belts are outfitted with components to facilitate the cell transport and rotation. The coordinated movement between the belts and the components promote the orderly transport and rotation of the cells from a substantially vertical stacking orientation into a substantially horizontal stacking orientation. The approach of the present invention helps keep the stacked assemblies stable so that subsequent assembly steps--such as compressing the cells or attaching electrical leads or thermal management components--may proceed with a reduced chance of error.

  20. A rapid numerical method for horizontal fluid flow in unsaturated soils

    NASA Astrophysics Data System (ADS)

    Kirby, J. M.

    1984-06-01

    A rapid numerical method for the horizontal flow of water is presented, based on the approximation for conductivity k = k0 exp (αψ). A simple expression for the velocity of flow is obtained, which produces accurate solutions to horizontal infiltration problems even with very large time and length steps. The method is compared with previous solutions, including the much studied Yolo light clay infiltration problems. These examples are used to demonstrate the accuracy and economy (in terms of the time and necessary computer power) of the solution. The method is accurate for any choice of length step, provided that the time step is below a certain limit which is related to the length step. An expression for estimating the maximum permissible time step is presented and its use demonstrated via one of the examples.

  1. System for Estimating Horizontal Velocity During Descent

    NASA Technical Reports Server (NTRS)

    Johnson, Andrew; Cheng, Yang; Wilson, Reg; Goguen, Jay; Martin, Alejandro San; Leger, Chris; Matthies, Larry

    2007-01-01

    The descent image motion estimation system (DIMES) is a system of hardware and software, designed for original use in estimating the horizontal velocity of a spacecraft descending toward a landing on Mars. The estimated horizontal velocity is used in generating rocket-firing commands to reduce the horizontal velocity as part of an overall control scheme to minimize the landing impact. DIMES can also be used for estimating the horizontal velocity of a remotely controlled or autonomous aircraft for purposes of navigation and control.

  2. Stepping motor controller

    DOEpatents

    Bourret, S.C.; Swansen, J.E.

    1982-07-02

    A stepping motor is microprocessor controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  3. Stepping motor controller

    DOEpatents

    Bourret, Steven C.; Swansen, James E.

    1984-01-01

    A stepping motor is microprocessingly controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  4. Step-Growth Polymerization.

    ERIC Educational Resources Information Center

    Stille, J. K.

    1981-01-01

    Following a comparison of chain-growth and step-growth polymerization, focuses on the latter process by describing requirements for high molecular weight, step-growth polymerization kinetics, synthesis and molecular weight distribution of some linear step-growth polymers, and three-dimensional network step-growth polymers. (JN)

  5. Widespread horizontal transfer of retrotransposons

    PubMed Central

    Walsh, Ali Morton; Kortschak, R. Daniel; Gardner, Michael G.; Bertozzi, Terry; Adelson, David L.

    2013-01-01

    In higher organisms such as vertebrates, it is generally believed that lateral transfer of genetic information does not readily occur, with the exception of retroviral infection. However, horizontal transfer (HT) of protein coding repetitive elements is the simplest way to explain the patchy distribution of BovB, a long interspersed element (LINE) about 3.2 kb long, that has been found in ruminants, marsupials, squamates, monotremes, and African mammals. BovB sequences are a major component of some of these genomes. Here we show that HT of BovB is significantly more widespread than believed, and we demonstrate the existence of two plausible arthropod vectors, specifically reptile ticks. A phylogenetic tree built from BovB sequences from species in all of these groups does not conform to expected evolutionary relationships of the species, and our analysis indicates that at least nine HT events are required to explain the observed topology. Our results provide compelling evidence for HT of genetic material that has transformed vertebrate genomes. PMID:23277587

  6. Widespread horizontal transfer of retrotransposons.

    PubMed

    Walsh, Ali Morton; Kortschak, R Daniel; Gardner, Michael G; Bertozzi, Terry; Adelson, David L

    2013-01-15

    In higher organisms such as vertebrates, it is generally believed that lateral transfer of genetic information does not readily occur, with the exception of retroviral infection. However, horizontal transfer (HT) of protein coding repetitive elements is the simplest way to explain the patchy distribution of BovB, a long interspersed element (LINE) about 3.2 kb long, that has been found in ruminants, marsupials, squamates, monotremes, and African mammals. BovB sequences are a major component of some of these genomes. Here we show that HT of BovB is significantly more widespread than believed, and we demonstrate the existence of two plausible arthropod vectors, specifically reptile ticks. A phylogenetic tree built from BovB sequences from species in all of these groups does not conform to expected evolutionary relationships of the species, and our analysis indicates that at least nine HT events are required to explain the observed topology. Our results provide compelling evidence for HT of genetic material that has transformed vertebrate genomes. PMID:23277587

  7. Widespread horizontal transfer of retrotransposons.

    PubMed

    Walsh, Ali Morton; Kortschak, R Daniel; Gardner, Michael G; Bertozzi, Terry; Adelson, David L

    2013-01-15

    In higher organisms such as vertebrates, it is generally believed that lateral transfer of genetic information does not readily occur, with the exception of retroviral infection. However, horizontal transfer (HT) of protein coding repetitive elements is the simplest way to explain the patchy distribution of BovB, a long interspersed element (LINE) about 3.2 kb long, that has been found in ruminants, marsupials, squamates, monotremes, and African mammals. BovB sequences are a major component of some of these genomes. Here we show that HT of BovB is significantly more widespread than believed, and we demonstrate the existence of two plausible arthropod vectors, specifically reptile ticks. A phylogenetic tree built from BovB sequences from species in all of these groups does not conform to expected evolutionary relationships of the species, and our analysis indicates that at least nine HT events are required to explain the observed topology. Our results provide compelling evidence for HT of genetic material that has transformed vertebrate genomes.

  8. Horizontally opposed internal combustion engine

    SciTech Connect

    Honkanen, E.G.

    1992-07-28

    This patent describes a internal combustion engine. It comprises a base plate coincident with a horizontal plane and generally symmetrical with respect to a central longitudinal axis coincident with a vertical plane extending between fore and aft ends of the base plate, a main power crankshaft suspended below the base plate and extending parallel with the central longitudinal axis, a plurality of open-ended piston cylinders disposed below the base plate arranged in axially aligned pairs, a pair of auxiliary crankshafts detachably journaled below the base plate on opposite sides of the vertical plane; a connecting rod assembly pivotally interconnecting the pair of auxiliary crankshafts with the main power crankshaft; a piston assembly in each of the cylinders operatively connected with the associated auxiliary crankshaft and including a piston having a head, a wrist-pin and a connecting rod connecting the wrist-pin of each piston with the associated auxiliary crankshaft; a fuel induction assembly for admitting a combustible fuel mixture into the cylinders between the opposed heads of the pistons in a controlled sequence correlated to the receding movement of the pistons in the cylinders in a fuel intake stroke; means for igniting the fuel mixture compressed between the juxtaposed heads of the pistons; means for exhausting from the cylinders the products of combustion of the fuel mixture in correlation to the movement of the pistons in an exhaust stroke; and means including an oil pan enclosing the auxiliary crankshafts.

  9. 13. CLOSEUP OF AFT BULKHEAD IN THE MAIN HOLD. HORIZONTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. CLOSE-UP OF AFT BULKHEAD IN THE MAIN HOLD. HORIZONTAL ALUMINUM SCALE RESTING ON STEP IS FOUR FEET LONG. THE BOTTOM OF THE HOLD IS MADE OF POURED CONCRETE AND HAS A CENTER DRAIN TO COLLECT WATER FROM MELTING ICE AND OTHER FLUIDS. THE DRAIN LED TO A SUMP CLEARED BY A BILGE PUMP WHICH PUMPED OVERBOARD. THE RECTANGULAR OPENING IN THE BULKHEAD WAS CUT TO ENABLE EASIER REMOVAL OF THE ENGINE AFTER THE EVELINA M. GOULART WAS ABANDONED. - Auxiliary Fishing Schooner "Evelina M. Goulart", Essex Shipbuilding Museum, 66 Main Street, Essex, Essex County, MA

  10. Worldwide experience shows horizontal well success

    SciTech Connect

    Karlsson, H.; Bitto, R.

    1989-03-01

    The convergence of technology and experience has made horizontal drilling an important tool in increasing production and solving a variety of completion problems. Since the early 1980s, horizontal drilling has been used to improve production on more than 700 oil and gas wells throughout the world. Approximately 200 horizontal wells were drilled in 1988 alone. Interest in horizontal drilling has been accelerating rapidly as service companies have developed and offered new technology for drilling and producing horizontal wells. Simultaneously, oil companies have developed better methods for evaluating reservoirs for potential horizontal applications, while their production departments have gained experience at completing and producing them. To date, most horizontal wells have been drilled in the United States. A major application is to complete naturally fractured formations, such as the Austin chalk in Texas, the Bakken shale in the Williston basin, the Spraberry in West Texas and the Devonian shale in the Eastern states. In addition, many horizontal wells have been drilled to produce the Niagaran reefs and the irregular Antrim shale reservoirs in Michigan.

  11. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Horizontal sectors. 84.17 Section 84.17 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INLAND NAVIGATION RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors....

  12. Detection of Horizontal Gene Transfers from Phylogenetic Comparisons

    PubMed Central

    Pylro, Victor Satler; Vespoli, Luciano de Souza; Duarte, Gabriela Frois; Yotoko, Karla Suemy Clemente

    2012-01-01

    Bacterial phylogenies have become one of the most important challenges for microbial ecology. This field started in the mid-1970s with the aim of using the sequence of the small subunit ribosomal RNA (16S) tool to infer bacterial phylogenies. Phylogenetic hypotheses based on other sequences usually give conflicting topologies that reveal different evolutionary histories, which in some cases may be the result of horizontal gene transfer events. Currently, one of the major goals of molecular biology is to understand the role that horizontal gene transfer plays in species adaptation and evolution. In this work, we compared the phylogenetic tree based on 16S with the tree based on dszC, a gene involved in the cleavage of carbon-sulfur bonds. Bacteria of several genera perform this survival task when living in environments lacking free mineral sulfur. The biochemical pathway of the desulphurization process was extensively studied due to its economic importance, since this step is expensive and indispensable in fuel production. Our results clearly show that horizontal gene transfer events could be detected using common phylogenetic methods with gene sequences obtained from public sequence databases. PMID:22675653

  13. Step by Step: Avoiding Spiritual Bypass in 12-Step Work

    ERIC Educational Resources Information Center

    Cashwell, Craig S.; Clarke, Philip B.; Graves, Elizabeth G.

    2009-01-01

    With spirituality as a cornerstone, 12-step groups serve a vital role in the recovery community. It is important for counselors to be mindful, however, of the potential for clients to be in spiritual bypass, which likely will undermine the recovery process.

  14. Horizontal fields generated by return strokes

    NASA Technical Reports Server (NTRS)

    Cooray, Vernon

    1991-01-01

    Horizontal fields generated by return strokes play an important role in the interaction of lightning generated electric fields with power lines. In many of the recent investigations on the interaction of lightning electromagnetic fields with power lines, the horizontal field was calculated by employing the expression for the tilt of the electric field of a plane wave propagating over finitely conducting earth. The method is suitable for calculating horizontal fields generated by return strokes at distances as close as 200m. At these close ranges, the use of the wavetilt expression can cause large errors.

  15. Influence of a Horizontal Approach on the Mechanical Output during Drop Jumps

    ERIC Educational Resources Information Center

    Ruan, Mianfang; Li, Li

    2008-01-01

    This study investigated the influence of a horizontal approach to mechanical output during drop jumps. Participants performed drop jumps from heights of 15, 30, 45, and 60 cm with zero, one, two, and three approach steps. The peak summed power during the push-off phase changed quadratically across heights (6.2 [plus or minus] 0.3, 6.7 [plus or…

  16. Recompletion by horizontal drilling pays off

    SciTech Connect

    Holifield, R.H.; Rehm, B.

    1989-03-01

    More than 20 wells have been recompleted in the Giddings field by drilling a new, horizontal interval from existing 5 1/2-in. cased wells for distances of 300 to 1,250 ft. Recompleting existing wells is much cheaper than drilling a new well. Plus, the new completions, overall, produce better. The horizontal wells are routinely profitable now, and pay out occurs in 3 to 24 months. During this program, the techniques for slim-hole- medium-radius, horizontal drilling in Giddings have been mastered and costs have dropped 75%. It is believed that this program may be the first (or among the first) continuing horizontal project drilled out of cased wells with repeatable profitability as opposed to projected viability.

  17. Horizontal sidetrack taps reservoir sweet spots''

    SciTech Connect

    Wible, J.R. )

    1994-02-21

    Cutting a window at 85[degree] deviation allowed a sidetrack to pass through the high-resistivity sections in a Gulf of Mexico reservoir. Results from logging-while-drilling (LWD) tools indicated the original horizontal bore dropped too low in the reservoir, possibly leading to a low productivity well. The subsequent sidetrack successfully delivered the desired well bore, and the increased productivity justified the efforts in cutting a window in the horizontal section.

  18. Report of the Horizontal Launch Study

    NASA Technical Reports Server (NTRS)

    Wilhite, Alan W.; Bartolotta, Paul A.

    2011-01-01

    A study of horizontal launch concepts has been conducted. This study, jointly sponsored by the Defense Advanced Research Projects Agency (DARPA) and the National Aeronautics and Space Administration (NASA) was tasked to estimate the economic and technical viability of horizontal launch approaches. The study team identified the key parameters and critical technologies which determine mission viability and reported on the state of the art of critical technologies, along with objectives for technology development.

  19. Emotion recognition (sometimes) depends on horizontal orientations

    PubMed Central

    Huynh, Carol M; Balas, Benjamin

    2014-01-01

    Face recognition depends critically on horizontal orientations (Goffaux & Dakin, 2010). Face images that lack horizontal features are harder to recognize than those that have that information preserved. Presently, we asked if facial emotional recognition also exhibits this dependency by asking observers to categorize orientation-filtered happy and sad expressions. Furthermore, we aimed to dissociate image-based orientation energy from object-based orientation by rotating images 90-degrees in the picture-plane. In our first experiment, we showed that the perception of emotional expression does depend on horizontal orientations and that object-based orientation constrained performance more than image-based orientation. In Experiment 2 we showed that mouth openness (i.e. open versus closed-mouths) also influenced the emotion-dependent reliance on horizontal information. Lastly, we describe a simple computational analysis that demonstrates that the impact of mouth openness was not predicted by variation in the distribution of orientation energy across horizontal and vertical orientation bands. Overall, our results suggest that emotion recognition does largely depend on horizontal information defined relative to the face, but that this bias is modulated by multiple factors that introduce variation in appearance across and within distinct emotions. PMID:24664854

  20. Cyclic steps on ice

    NASA Astrophysics Data System (ADS)

    Yokokawa, M.; Izumi, N.; Naito, K.; Parker, G.; Yamada, T.; Greve, R.

    2016-05-01

    Boundary waves often form at the interface between ice and fluid flowing adjacent to it, such as ripples under river ice covers, and steps on the bed of supraglacial meltwater channels. They may also be formed by wind, such as the megadunes on the Antarctic ice sheet. Spiral troughs on the polar ice caps of Mars have been interpreted to be cyclic steps formed by katabatic wind blowing over ice. Cyclic steps are relatives of upstream-migrating antidunes. Cyclic step formation on ice is not only a mechanical but also a thermodynamic process. There have been very few studies on the formation of either cyclic steps or upstream-migrating antidunes on ice. In this study, we performed flume experiments to reproduce cyclic steps on ice by flowing water, and found that trains of steps form when the Froude number is larger than unity. The features of those steps allow them to be identified as ice-bed analogs of cyclic steps in alluvial and bedrock rivers. We performed a linear stability analysis and obtained a physical explanation of the formation of upstream-migrating antidunes, i.e., precursors of cyclic steps. We compared the results of experiments with the predictions of the analysis and found the observed steps fall in the range where the analysis predicts interfacial instability. We also found that short antidune-like undulations formed as a precursor to the appearance of well-defined steps. This fact suggests that such antidune-like undulations correspond to the instability predicted by the analysis and are precursors of cyclic steps.

  1. Golgi-Cox Staining Step by Step

    PubMed Central

    Zaqout, Sami; Kaindl, Angela M.

    2016-01-01

    Golgi staining remains a key method to study neuronal morphology in vivo. Since most protocols delineating modifications of the original staining method lack details on critical steps, establishing this method in a laboratory can be time-consuming and frustrating. Here, we describe the Golgi-Cox staining in such detail that should turn the staining into an easily feasible method for all scientists working in the neuroscience field. PMID:27065817

  2. Response of carp (Cyprinus carpio) horizontal cells to heterochromatic flicker photometry.

    PubMed

    De Aguiar, Marlison José L; Ventura, Dora Fix; da Silva Filho, Manoel; de Souza, John Manuel; Maciel, Rogério; Lee, Barry B

    2006-01-01

    The objective of the present work was to determine the interaction of cone inputs in the response of horizontal cells using heterochromatic flicker photometry (HFP). Intracellular electrophysiological recordings were made in horizontal cells of isolated retinae of carp maintained in physiological solution, with the receptor side up. Sharp glass microelectrodes filled with 3 M KCl solution with resistances between 100 and 120 M Omega were used. Stimuli comprised six cycles of two 6-Hz sinusoidal light waves in counterphase adjusted for the same number of quanta: a green light (550 nm) from a monochromator with a Xenon lamp and an LED red light (628 nm). The stimulation program consisted of 10 steps with the 550-nm wave at constant amplitude, while the 628-nm wave varied in increments of 10% up to 100%, followed by another 10 steps with the 628-nm wave at constant amplitude while the 550-nm wave varied in increments of 10% up to 100%. We recorded responses from four different horizontal cell classes: H1 (monophasic, broadband, n = 37), H2 (biphasic, red-green color-opponent, n = 13), and H3 (biphasic, blue-yellow color-opponent, n = 2) cone horizontal cells; and RH (monophasic, broadband, n = 3) rod horizontal cells. H1 and RH horizontal cells showed a similar cancellation point at a heterochromatic mixture consistent with mixed inputs from 630- and 550-nm cones. No cancellation point was found for the H2 cell class. Fish H1 cells add cone inputs and signal "luminance" in light levels appropriate for cone stimulation. The same occurs with RH cells, which also signal "luminance," but in light levels appropriate for rod work. For both cell classes there is an HFP cancellation point occurring at a combination of 628-nm and 550-nm lights in opposing phase that leads to the cancellation of the cell's response. No cancellation was found for H2 and H3 cells, which are the chromatically opponent horizontal cells in lower vertebrates.

  3. How to drill horizontal sections faster

    SciTech Connect

    Chaffin, M. )

    1991-12-01

    This paper reports that fewer trips, reduced slide time and lower drag during sliding have resulted from the application of downhole-adjustable stabilizers to horizontal drilling. Faster drilling times mean lower measurement while drilling (MWD) cost, and less wear on downhole equipment, motors and bits. These advantages combined with reduced drilling shocks have increased drilling rates and efficiency. Applying existing technology in new situations is an important way of reducing the cost of finding, exploring for and developing reserves. Engineers are responsible for using current technology to its fullest and developing new technology to reduce drilling expenses. Horizontal drilling was used in its early stages to develop the Austin chalk formation in Pearsall oil field more effectively. As procedures were generated to drill horizontal wells, Oryx drilling engineers began to develop new technology and investigate ways for existing technology to be used or altered to fit horizontal drilling programs. The new technology of downhole-adjustable stabilizers has been used successfully to further improve horizontal drilling efficiency.

  4. STEP Experiment Requirements

    NASA Technical Reports Server (NTRS)

    Brumfield, M. L. (Compiler)

    1984-01-01

    A plan to develop a space technology experiments platform (STEP) was examined. NASA Langley Research Center held a STEP Experiment Requirements Workshop on June 29 and 30 and July 1, 1983, at which experiment proposers were invited to present more detailed information on their experiment concept and requirements. A feasibility and preliminary definition study was conducted and the preliminary definition of STEP capabilities and experiment concepts and expected requirements for support services are presented. The preliminary definition of STEP capabilities based on detailed review of potential experiment requirements is investigated. Topics discussed include: Shuttle on-orbit dynamics; effects of the space environment on damping materials; erectable beam experiment; technology for development of very large solar array deployers; thermal energy management process experiment; photovoltaic concentrater pointing dynamics and plasma interactions; vibration isolation technology; flight tests of a synthetic aperture radar antenna with use of STEP.

  5. Horizontal drilling techniques at Prudhoe Bay, Alaska

    SciTech Connect

    Wilkirson, J.P.; Smith, J.H.; Stagg, T.O.; Walters, D.A.

    1986-01-01

    Three extended departure horizontal wells have been drilled and completed at Prudhoe Bay, Alaska by Standard Alaska Production Company. Horizontal slotted liner completions of 1575 feet (480 m), 1637 feet (499 m), and 1163 feet (354 m) were accomplished at an average vertical depth of 9000 feet (2743 m). Improvements in technology and operating procedures have resulted in a cost per foot reduction of 40% over the three well program. When compared to conventional completions, initial production data indicates rate benefits of 300% and a major increase in ultimate recovery. This paper discusses the development of the techniques used to drill horizontal wells at Prudhoe Bay and reviews the drilling operations for each well.

  6. ESP's placed in horizontal lateral increase production

    SciTech Connect

    Gallup, A.; Wilson, B.L. ); Marshall, R. )

    1990-06-18

    By design, the electric submersible pump (ESP) is an effective method of lifting fluids from horizontal wells. But this ESP application does have unique installation and operating parameters that need to be considered. ESP's have been used for many years in directional wells. This application provides an experience base for understanding deflection limits on the unit. To avoid damaging the ESP, special equipment may be required in some horizontal installations. This paper discusses how several ESP's have been designed specifically for medium-radius wells. In these applications, the deeper pump setting provides for a significant increase in production rate. In general, to realize the full benefit of a horizontal installation, the ESP should be considered when planning, drilling, and completing the well.

  7. Successful horizontal completions require an integrated approach

    SciTech Connect

    Richard, B.; Smejkal, K.; Penberthy, W. Jr.

    1997-01-01

    While a perfect well completion may not exist, depleting a hydrocarbon resource at a sustained high rate--without a workover--is the ultimate goal. Unfortunately, many horizontal well completions fail to achieve this due to wellbore damage or loss of reservoir pressure. These conditions manifest themselves in reduced production rates, extended well life and reduced profitability. Standard completion techniques are not always compatible with each other for site specific well applications. The combination of two incompatible technologies or slight changes in a completion procedure may negatively impact productivity. Hence, the most successful horizontal completion results are obtained using a compatible integrated system approach--an approach that carefully combines the best completion tools and processes to deliver an undamaged well completed at the lowest possible cost. After studying the compatibilities of various drill-in fluids, screens, filter cakes and gravel packs, recommended procedures are presented for successfully completing horizontal wells.

  8. Space shuttle horizontal flight test plan

    NASA Technical Reports Server (NTRS)

    Mosley, R. L.

    1972-01-01

    A horizontal takeoff flight test concept for testing space shuttle vehicles is presented. The guidelines used in planning and support requirements for the flight tests are developed. Details of the test program are provided. The instrumentation requirements are defined. The limitations imposed by the short flight endurance and restricted maneuvering capability of the shuttle booster/orbiter in the horizontal mode are described. The test program covers the following investigations. (1) stall and lift boundary tests, (2)takeoff and landing tests, (3) level flight speed power tests, (4) longitudinal and laterial directional dynamic stability, and (5) static directional stability.

  9. Stepping back to improve sprint performance: a kinetic analysis of the first step forwards.

    PubMed

    Frost, David M; Cronin, John B

    2011-10-01

    Using a step backward to initiate forward movement can increase force and power at push-off and improve sprint performance over short distances. However, it is not clear whether the benefit provided by this paradoxical step influences the mechanics of the first step forwards. Twenty-seven men of an athletic background performed maximal effort 5-m sprints from a standing start and employed a step forwards (parallel and split stance) or backwards (false) to initiate movement. Each sprint was started with an audio cue that also activated the timing gates. Three trials of each starting style were performed and movement (0 m), 2.5-, and 5-m times were recorded. An in-ground force plate placed at the 0-m mark measured the kinetic and temporal characteristics of the first step. Sprint times to 2.5 and 5 m were slower (p < 0.05) when a parallel start was used. No differences were seen in the normalized peak forces (vertical and horizontal) or the vertical impulse between starts, but the vertical mean force was 11 and 12% higher for the false and split starts, respectively. Surprisingly, the parallel start's impulse was significantly greater than that of the false (24%) and split (22%) styles, a consequence of the additional time spent in contact with the ground. The ground contact time, time to peak force, and time from peak force to toe-off (vertical and horizontal) were significantly longer for the parallel start. These temporal variables were also better correlated with sprint performance than any kinetic measure (0.42 ≤ r ≤ 0.75). The false start appears to be advantageous over short distances by improving push-off and the temporal characteristics of the first step.

  10. The Next Giant Step

    NASA Video Gallery

    Artist Robert McCall painted "The Next Giant Step" in 1979 to commemorate the heroism and courage of spaceflight pioneers. Located in the lobby of Johnson's building 2, the mural depicts America's ...

  11. A big first step.

    PubMed

    Jones, Howard W

    2004-11-01

    The singleton, term gestation, live birth rate per cycle initiated (BESST) endpoint proposed at the beginning of 2004 is a first big step which should be added to by the consideration of multiple pregnancy rates in relation to singleton rates, by recording of fetal reductions and of pregnancies resulting from cryopreserved material. After three or more steps we may have an accurate reporting system which helps patients to distinguish the pros and cons for singleton term delivery. PMID:15479704

  12. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... practical cut-off at not more than 5 degrees outside the prescribed sectors. (b) All-round lights shall be... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors. (a)(1... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside...

  13. 33 CFR 84.17 - Horizontal sectors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... practical cut-off at not more than 5 degrees outside the prescribed sectors. (b) All-round lights shall be... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.17 Horizontal sectors. (a)(1... intensities. The intensities shall decrease to reach practical cut-off between 1 and 3 degrees outside...

  14. Horizontally separated 1-in-1 crossing insertions

    SciTech Connect

    Syphers, M.J.

    1985-10-01

    Previous to this workshop, realistic lattices have been developed for vertically separated l-in-l (e.g., D.E. Johnson, A.A. Garren) and 2-in-1 (e.g., S. Heifets) magnets as well as for horizontally separated 2-in-l magnets (e.g., SSC RDS). Bringing together the widely separated ({approximately}60-70 cm) beams in a reasonable length of tunnel and keeping the dispersion zero at the interaction point has been difficult in the vertical l-in-l case. Most designs have required spacial 2-in-1 quadrupoles near the interaction point where the beams are separated by 15 cm or less. It is not clear that such magnets, as dictated by some of these lattice designs, can easily be built. The purpose of this exercise is to provide a crossing insertion for a realistic lattice which involves horizontally separated l-in-l magnets. The following horizontal crossing insertions, which incorporate the dispersion suppressors and phase trombones into the major arcs, need no special 2-in-1 magnets near the interaction point. The dispersion at the IP created by the horizontal crossing can be cancelled by the dispersion suppressor and one set of triplets.

  15. A laboratory investigation of cementing horizontal wells

    SciTech Connect

    Wilson, M.A.; Sabins, F.L. )

    1988-09-01

    Obtaining a successful cement job will remain one of the most important factors to the productive life of any well and will be especially critical for horizontal-well completions. Achieving a high mud-displacement efficiency under highly deviated or horizontal-well conditions requires that special attention be given to the many aspects of drilling/completion practices - e.g., drill-fluid systems and properties and casing and hole sizes - to obtain optimum mud displacement and cementing results. A study of factors affecting mud-displacement efficiency focused on cementing an ultralow-permeability formation that is being evaluated as a subject for horizontal completion. Realistic laboratory testing was conducted on a large-scale test model that has been used for many years to evaluate factors influencing drilling-fluid displacement efficiency. Factors evaluated for this study included influence of hold and pipe sizes, pipe centralization, displacement rates, and spacer systems. Findings from this study provided specific recommendations for low-permeability reservoirs that also can be applied to horizontally drilled wells. Various techniques for cementing horizonal wells will be discussed and general recommendations will be given.

  16. Cutting Down the Tall Poppies: Horizontal Violence.

    ERIC Educational Resources Information Center

    Funk, Carole

    Many women in educational leadership positions experience negative treatment from female teachers and female superintendents. This phenomenon is known as horizontal violence, "the curious behavior of members of oppressed groups who often lash out at their peers in response to oppression instead of attacking their oppressors." This paper explores…

  17. [From vertical to horizontal. Writing in adolescence].

    PubMed

    Catheline-Antipoff, N

    1995-04-01

    Writing at adolescence has a non negligible part in identity's construction. Vertical writing as tags, graphs and graffiti refer to a narcissism deficiency and express a pulsional necessity, whereas, horizontal writing as private diaries, letters and novels express object's search and are made in dreaming attitude.

  18. Electroluminescence from completely horizontally oriented dye molecules

    NASA Astrophysics Data System (ADS)

    Komino, Takeshi; Sagara, Yuta; Tanaka, Hiroyuki; Oki, Yuji; Nakamura, Nozomi; Fujimoto, Hiroshi; Adachi, Chihaya

    2016-06-01

    A complete horizontal molecular orientation of a linear-shaped thermally activated delayed fluorescent guest emitter 2,6-bis(4-(10Hphenoxazin-10-yl)phenyl)benzo[1,2-d:5,4-d'] bis(oxazole) (cis-BOX2) was obtained in a glassy host matrix by vapor deposition. The orientational order of cis-BOX2 depended on the combination of deposition temperature and the type of host matrix. Complete horizontal orientation was obtained when a thin film with cis-BOX2 doped in a 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) host matrix was fabricated at 200 K. The ultimate orientation of guest molecules originates from not only the kinetic relaxation but also the kinetic stability of the deposited guest molecules on the film surface during film growth. Utilizing the ultimate orientation, a highly efficient organic light-emitting diode with the external quantum efficiency of 33.4 ± 2.0% was realized. The thermal stability of the horizontal orientation of cis-BOX2 was governed by the glass transition temperature (Tg) of the CBP host matrix; the horizontal orientation was stable unless the film was annealed above Tg.

  19. Horizontal Axis Levitron--A Physics Demonstration

    ERIC Educational Resources Information Center

    Michaelis, Max M.

    2014-01-01

    After a brief history of the Levitron, the first horizontal axis Levitron is reported. Because it is easy to operate, it lends itself to educational physics experiments and analogies. Precession and nutation are visualized by reflecting the beam from a laser pointer off the "spignet". Precession is fundamental to nuclear magnetic…

  20. Dairy washwater treatment using a horizontal flow biofilm system.

    PubMed

    Rodgers, M; de Paor, D; Clifford, E

    2008-01-01

    In Ireland, dairy farmyard washwater commonly comprises farmyard run-off and dairy parlour washings. Land-spreading is the most widely used method for treating this wastewater. However, this method can be labour intensive and can cause, in some cases, the degradation of surface and ground waters, mainly due to nitrogen contamination. In this study, a horizontal flow biofilm reactor (HFBR) with step-feed was constructed and tested in the laboratory, to remove organic carbon and nitrogen from a agricultural strength synthetic washwater (SWW). The HFBR had an average top plan surface area (TPSA) of 0.1002 m(2) and consisted of a stack of 45 polystyrene horizontal sheets--15 sheets embedded with 25 mm deep frustums above 30 sheets with 10 mm deep frustums. The frustums acted as miniature reservoirs. The sheets were alternately offset to allow the wastewater to flow horizontally along each sheet and vertically from sheet to sheet down through the reactor. Biofilms developed on the sheets and treated the wastewater. During the 212-d study, the total hydraulic loading rate based on the TPSA of the sheets was 35 l m(-2) d(-1). SWW was pumped for 10 min each hour, in a step feed arrangement at a rate of 23.33 l m(-2) d(-1) on to the top sheet during Phases 1 and 2, and 11.67 l m(-2) d(-1) onto Sheet 16 during Phase 1 (days 1-92) and onto Sheet 30 during Phase 2 (days 93-212). The substrate loading rate during Phases 1 and 2 was 94.8 g total chemical oxygen demand (COD) m(-2) d(-1) and 10.5 g total nitrogen (TN) m(-2) d(-1), based on the TPSA. At steady state in Phase 2, the unit achieved excellent carbon removal of 99.7% 5-day biochemical oxygen demand (BOD(5)) and 96.7% total COD, equivalent to TPSA removal rates of 67.5 g BOD(5)m(-2)d(-1) and 91.7 g COD m(-2) d(-1). The nitrogen removal percentages were 98.3% total ammonium-nitrogen (NH(4)-N(t)) and 72.8% TN, which equated to TPSA removal rates of 4.8 g NH(4)-N(t) m(-2) d(-1) and 7.6g TN m(-2) d(-1). No sloughing of

  1. Articulating Support for Horizontal Resistive Exercise

    NASA Technical Reports Server (NTRS)

    Gundo, Daniel; Schaffner, Grant; Bentley, Jason; Loehr, James A.

    2005-01-01

    A versatile mechanical device provides support for a user engaged in any of a variety of resistive exercises in a substantially horizontal orientation. The unique features and versatility of the device promise to be useful in bedrest studies, rehabilitation, and specialized strength training. The device affords a capability for selectively loading and unloading of portions of the user s body through its support mechanisms, so that specific parts of the body can be trained with little or no effect on other parts that may be disabled or in the process of recovery from injury. Thus, the device is ideal for rehabilitation exercise programs prescribed by physicians and physical therapists. The capability for selective loading and support also offers potential benefits to strength and conditioning trainers and athletes who wish to selectively strengthen selected parts. The principal innovative aspect of the device is that it supports the subject s weight while enabling the subject, lying substantially horizontally, to perform an exercise that closely approximates a full standing squat. The device includes mechanisms that support the subject in such a way that the hips are free to translate both horizontally and vertically and are free to rotate about the line connecting the hips. At the same time, the shoulders are free to translate horizontally while the upper back is free to rotate about the line connecting the shoulders. Among the mechanisms for hip motion and support is a counterbalance that offsets the weight of the subject as the subject s pelvis translates horizontally and vertically and rotates the pelvis about the line connecting the hips. The counterbalance is connected to a pelvic support system that allows these pelvic movements. The subject is also supported at the shoulder by a mechanism that can tilt to provide continuous support of the upper back while allowing the rotation required for arching the back as the pelvis is displaced. The shoulder support

  2. Horizontal modular dry irradiated fuel storage system

    DOEpatents

    Fischer, Larry E.; McInnes, Ian D.; Massey, John V.

    1988-01-01

    A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

  3. Elf cites 5 advantages of horizontal drilling

    SciTech Connect

    Not Available

    1984-06-01

    ELF Aquitaine used horizontal drilling during a pilot test program to bring commercial production from its Rospo Mare oil discovery in the Adriatic, which would have been a costly disappointment if drilled by a conventional vertical well bore. Rospo Mare is a large reservoir containing a top column of highly viscous crude underlain by a water column. The company felt that a well bore that penetrated the reservoir vertically would bring early flooding of the oil column and yield only water. By penetrating the reservoir with a horizontal well drilled high in the oil column, the well successfully produced on numerous tests from Oct. 1982 until the end of the test program in 1983. Production was termed excellent, with productivity during tests reportedly reaching ca 15 times the rate produced from nearby vertical wells. However, ELF said the results usually average ca 5 times the usual rate of vertical wells.

  4. Film condensation in a horizontal rectangular duct

    NASA Technical Reports Server (NTRS)

    Lu, Qing; Suryanarayana, N. V.

    1993-01-01

    Condensation heat transfer in a horizontal rectangular duct was experimentally and analytically investigated. To prevent the dripping of condensate on the film, the experiment was conducted inside a horizontal rectangular duct with vapor condensing only on the bottom cooled plate of the duct. R-113 and FC-72 (Fluorinert Electronic Fluid developed by the 3M Company) were used as the condensing fluids. The experimental program included measurements of film thickness, local and average heat transfer coefficients, wave length, wave speed, and a study of wave initiation. The measured film thickness was used to obtain the local heat transfer coefficient. The wave initiation was studied both with condensation and with an adiabatic air-liquid flow. The test sections used in both experiments were identical.

  5. Horizontal slug flow modeling and metering

    SciTech Connect

    Kouba, G.E.

    1986-01-01

    An experimental and theoretical investigation of horizontal two-phase slug flow was performed with the purpose of developing a method to measure the in-situ flow rates of the liquid and the gas phases using non-intrusive devices. A microcomputer based data acquisition system was used to acquire slug flow data on a 3 in.(76.2 mm) diameter, 1370 ft (418 m) long, horizontal pipeline. These data include the following slug characteristics: liquid holdups in the slug and film, slug and gas pocket lengths, and slug translational velocity. The data were gathered over a wide range of flow conditions in groups of constant superficial liquid and mixture velocities. The volumetric phase flow rate equation, for either liquid or gas, was developed for slug flow conditions. Within the flow rate equation, a key flow distribution parameter was defined that related the phase velocity in the slug to the translational velocity of the slug.

  6. Stepped inlet optical panel

    DOEpatents

    Veligdan, James T.

    2001-01-01

    An optical panel includes stacked optical waveguides having stepped inlet facets collectively defining an inlet face for receiving image light, and having beveled outlet faces collectively defining a display screen for displaying the image light channeled through the waveguides by internal reflection.

  7. Horizontal drilling in shallow, geologically complex reservoirs

    SciTech Connect

    Venable, S.D.

    1992-01-01

    The objective of this project is to test the concept that multiple hydraulic fracturing from a directionally-drilled horizontal well, using the medium radius build rate method, can increase gas production sufficiently to justify economic viability over conventional stimulated vertical wells. The test well is located in Yuma County, Colorado, in a favorable area of established production to avoid exploration risks. This report presents: background information; project description which covers location selection/geologic considerations; and preliminary work plan. (AT)

  8. Horizontal drilling in shallow, geologically complex reservoirs

    SciTech Connect

    Venable, S.D.

    1992-10-01

    The objective of this project is to test the concept that multiple hydraulic fracturing from a directionally-drilled horizontal well, using the medium radius build rate method, can increase gas production sufficiently to justify economic viability over conventional stimulated vertical wells. The test well is located in Yuma County, Colorado, in a favorable area of established production to avoid exploration risks. This report presents: background information; project description which covers location selection/geologic considerations; and preliminary work plan. (AT)

  9. Management of horizontally impacted dilacerated lateral incisor

    PubMed Central

    Katta, Anil Kumar; Peddu, Revathi; Vannala, Venkataramana; Dasari, Vaishnavi

    2015-01-01

    Impaction of maxillary lateral incisor with odontome and retained deciduous tooth is not often seen in regular dental practice. Impaction of anterior teeth cause generalized spacing which affects the esthetics of the face. Here we report a case of an 18-year-old patient with horizontally impacted dilacerated lateral incisor, which was bought into occlusion with the help of orthodontic tooth movement within a span of 18 months. PMID:26538954

  10. Spin stabilized magnetic levitation of horizontal rotors.

    SciTech Connect

    Romero, Louis Anthony

    2004-10-01

    In this paper we present an analysis of a new configuration for achieving spin stabilized magnetic levitation. In the classical configuration, the rotor spins about a vertical axis; and the spin stabilizes the lateral instability of the top in the magnetic field. In this new configuration the rotor spins about a horizontal axis; and the spin stabilizes the axial instability of the top in the magnetic field.

  11. Cellular Distribution and Subcellular Localization of Molecular Components of Vesicular Transmitter Release in Horizontal Cells of Rabbit Retina

    PubMed Central

    HIRANO, ARLENE A.; BRANDSTÄTTER, JOHANN H.; BRECHA, NICHOLAS C.

    2010-01-01

    The mechanism underlying transmitter release from retinal horizontal cells is poorly understood. We investigated the possibility of vesicular transmitter release from mammalian horizontal cells by examining the expression of synaptic proteins that participate in vesicular transmitter release at chemical synapses. Using immunocytochemistry, we evaluated the cellular and subcellular distribution of complexin I/II, syntaxin-1, and synapsin I in rabbit retina. Strong labeling for complexin I/II, proteins that regulate a late step in vesicular transmitter release, was found in both synaptic layers of the retina, and in somata of A- and B-type horizontal cells, of γ-aminobutyric acid (GABA)- and glycinergic amacrine cells, and of ganglion cells. Immunoelectron microscopy demonstrated the presence of complexin I/II in horizontal cell processes postsynaptic to rod and cone ribbon synapses. Syntaxin-1, a core protein of the soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) complex known to bind to complexin, and synapsin I, a synaptic vesicle-associated protein involved in the Ca2+-dependent recruitment of synaptic vesicles for transmitter release, were also present in the horizontal cells and their processes at photoreceptor synapses. Photoreceptors and bipolar cells did not express any of these proteins at their axon terminals. The presence of complexin I/II, syntaxin-1, and synapsin I in rabbit horizontal cell processes and tips suggests that a vesicular mechanism may underlie transmitter release from mammalian horizontal cells. PMID:15912504

  12. Contribution of irregular semicircular canal afferents to the horizontal vestibuloocular response during constant velocity rotation

    NASA Technical Reports Server (NTRS)

    Angelaki, D. E.; Perachio, A. A.

    1993-01-01

    1. The effects of constant anodal currents (100 microA) delivered bilaterally to both labyrinths on the horizontal vestibuloocular response (VOR) were studied in squirrel monkeys during steps of angular velocity in the dark. We report that bilateral anodal currents decreased eye velocity approximately 30-50% during the period of galvanic stimulation without a change in the time constant of VOR. The decrease in eye velocity, present during steps of angular velocity, was not observed during sinusoidal head rotation at 0.2, 0.5, and 1 Hz. The results suggest that responses from irregular vestibular afferents influence VOR amplitude during constant velocity rotation.

  13. Axial segregation of horizontally vibrated binary granular mixtures in an offset-Christmas tree channel

    NASA Astrophysics Data System (ADS)

    Bhateja, Ashish; Sharma, Ishan; Singh, Jayant K.

    2013-06-01

    We investigate segregation in a horizontally vibrated binary granular mixture in a closed offset-Christmas tree channel. The segregation phenomenon occurs in two steps: vertical sorting followed by axial segregation. In the first step, sorting occurs via Brazil-nut effect or reverse Brazil-nut effect depending on the particles' size and density ratios. The two layers thus formed then separate axially towards opposite-ends of the channel with the top layer always moving towards root of the Christmas tree. We discuss the segregation mechanism responsible for axial segregation.

  14. 12. VIEW LOOKING SOUTHWEST, CHESTNUT ST. (lower horizontal line) TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW LOOKING SOUTHWEST, CHESTNUT ST. (lower horizontal line) TO WALNUT ST. (upper horizontal line), SHOWING SECOND BANK OF U.S. - Independence National Historical Park, Walnut, Sixth, Chestnut & Second Streets, Philadelphia, Philadelphia County, PA

  15. Micromachine Wedge Stepping Motor

    SciTech Connect

    Allen, J.J.; Schriner, H.K.

    1998-11-04

    A wedge stepping motor, which will index a mechanism, has been designed and fabricated in the surface rnicromachine SUMMiT process. This device has demonstrated the ability to index one gear tooth at a time with speeds up to 205 teeth/see. The wedge stepper motor has the following features, whi:h will be useful in a number of applications. o The ability to precisely position mechanical components. . Simple pulse signals can be used for operation. o Only 2 drive signals are requixed for operation. o Torque and precision capabilities increase with device size . The device to be indexed is restrained at all times by the wedge shaped tooth that is used for actuation. This paper will discuss the theory of operation and desi=m of the wedge stepping motor. The fabrication and testing of I he device will also be presented.

  16. The digital step edge

    NASA Technical Reports Server (NTRS)

    Haralick, R. M.

    1982-01-01

    The facet model was used to accomplish step edge detection. The essence of the facet model is that any analysis made on the basis of the pixel values in some neighborhood has its final authoritative interpretation relative to the underlying grey tone intensity surface of which the neighborhood pixel values are observed noisy samples. Pixels which are part of regions have simple grey tone intensity surfaces over their areas. Pixels which have an edge in them have complex grey tone intensity surfaces over their areas. Specially, an edge moves through a pixel only if there is some point in the pixel's area having a zero crossing of the second directional derivative taken in the direction of a non-zero gradient at the pixel's center. To determine whether or not a pixel should be marked as a step edge pixel, its underlying grey tone intensity surface was estimated on the basis of the pixels in its neighborhood.

  17. Proper horizontal photospheric flows in a filament channel

    NASA Astrophysics Data System (ADS)

    Schmieder, B.; Roudier, T.; Mein, N.; Mein, P.; Malherbe, J. M.; Chandra, R.

    2014-04-01

    Context. An extended filament in the central part of the active region NOAA 11106 crossed the central meridian on Sept. 17, 2010 in the southern hemisphere. It has been observed in Hα with the THEMIS telescope in the Canary Islands and in 304 Å with the EUV imager (AIA) onboard the Solar Dynamic Observatory (SDO). Counterstreaming along the Hα threads and bright moving blobs (jets) along the 304 Å filament channel were observed during 10 h before the filament erupted at 17:03 UT. Aims: The aim of the paper is to understand the coupling between magnetic field and convection in filament channels and relate the horizontal photospheric motions to the activity of the filament. Methods: An analysis of the proper photospheric motions using SDO/HMI continuum images with the new version of the coherent structure tracking (CST) algorithm developed to track granules, as well as the large scale photospheric flows, was performed for three hours. Using corks, we derived the passive scalar points and produced a map of the cork distribution in the filament channel. Averaging the velocity vectors in the southern hemisphere in each latitude in steps of 3.5 arcsec, we defined a profile of the differential rotation. Results: Supergranules are clearly identified in the filament channel. Diverging flows inside the supergranules are similar in and out of the filament channel. Converging flows corresponding to the accumulation of corks are identified well around the Hα filament feet and at the edges of the EUV filament channel. At these convergence points, the horizontal photospheric velocity may reach 1 km s-1, but with a mean velocity of 0.35 km s-1. In some locations, horizontal flows crossing the channel are detected, indicating eventually large scale vorticity. Conclusions: The coupling between convection and magnetic field in the photosphere is relatively strong. The filament experienced the convection motions through its anchorage points with the photosphere, which are

  18. Study of the Local Horizon. (Spanish Title: Estudio del Horizonte Local.) Estudo do Horizonte Local

    NASA Astrophysics Data System (ADS)

    Ros, Rosa M.

    2009-12-01

    The study of the horizon is fundamental to easy the first observations of the students at any education center. A simple model, to be developed in each center, allows to easy the study and comprehension of the rudiments of astronomy. The constructed model is presented in turn as a simple equatorial clock, other models (horizontal and vertical) may be constructed starting from it. El estudio del horizonte es fundamental para poder facilitar las primeras observaciones de los alumnos en un centro educativo. Un simple modelo, que debe realizarse para cada centro, nos permite facilitar el estudio y la comprensión de los primeros rudimentos astronómicos. El modelo construido se presenta a su vez como un sencillo modelo de reloj ecuatorial y a partir de él se pueden construir otros modelos (horizontal y vertical). O estudo do horizonte é fundamental para facilitar as primeiras observações dos alunos num centro educativo. Um modelo simples, que deve ser feito para cada centro, permite facilitar o estudo e a compreensão dos primeiros rudimentos astronômicos. O modelo construído apresenta-se, por sua vez, como um modelo simples de relógio equatorial e a partir dele pode-se construir outros modelos (horizontal e vertical)

  19. YPF uses horizontal reentry to aid thin bed production

    SciTech Connect

    Acosta, M.R.; Leiro, F.A.; Sesano, G.S.; Hill, D.

    1997-01-01

    Reentry and horizontal drilling/completion techniques have proven themselves useful in exploiting thin beds. A pilot horizontal reentry contracted by Yacimiento Petroliferos Fiscales (YPF) for a marginal well in its Lomita Sur field resulted in decreased water coning and production rates four times greater than expected. Further horizontal reentries in this thin-bed field are planned.

  20. Sidewall containment of liquid metal with horizontal alternating magnetic fields

    DOEpatents

    Praeg, Walter F.

    1995-01-01

    An apparatus for confining molten metal with a horizontal alternating magnetic field. In particular, this invention employs a magnet that can produce a horizontal alternating magnetic field to confine a molten metal at the edges of parallel horizontal rollers as a solid metal sheet is cast by counter-rotation of the rollers.

  1. Sidewall containment of liquid metal with horizontal alternating magnetic fields

    DOEpatents

    Pareg, Walter F.

    1990-01-01

    An apparatus for confining molten metal with a horizontal alternating magnetic field. In particular, this invention employs a magnet that can produce a horizontal alternating magnetic field to confine a molten metal at the edges of parallel horizontal rollers as a solid metal sheet is cast by counter-rotation of the rollers.

  2. Horizontal core acquisition and orientation for formation evaluation

    SciTech Connect

    Skopec, R.A. ); Mann, M.M. ); Grier, S.P. )

    1992-03-01

    The increase in horizontal drilling activity has produced a need for improved coring technology. The development of a reliable horizontal (medium-radius) coring and orientation system has greatly improved the acquisition of information necessary for formation evaluation and reservoir engineering. This paper describes newly developed hardware and methods for obtaining horizontal core sections.

  3. Effect of turbulence intensity on cross-injection film cooling at a stepped or smooth endwall of a gas turbine vane passage.

    PubMed

    Wu, Pey-Shey; Tsai, Shen-Ta; Jhuo, Yue-Hua

    2014-01-01

    This study is concerned with a film cooling technique applicable to the protection of the endwalls of a gas turbine vane. In the experiments, cross-injection coolant flow from two-row, paired, inclined holes with nonintersecting centerlines was utilized. The test model is a scaled two-half vane. The levels of turbulence intensity used in the experiments are T.I. = 1.8%, 7%, and 12%. Other parameters considered in the film cooling experiments include three inlet Reynolds numbers (9.20 × 10(4), 1.24 × 10(5), and 1.50 × 10(5)), three blowing ratios (0.5, 1.0, and 2.0), and three endwall conditions (smooth endwall and stepped endwall with forward-facing or backward-facing step). Thermochromic liquid crystal (TLC) technique with steady-state heat transfer experiments was used to obtain the whole-field film cooling effectiveness. Results show that, at low turbulence intensity, increasing Reynolds number decreases the effectiveness in most of the vane passage. There is no monotonic trend of influence by Reynolds number at high turbulence intensity. The effect of blowing ratio on the effectiveness has opposite trends at low and high turbulence levels. Increasing turbulent intensity decreases the effectiveness, especially near the inlet of the vane passage. With a stepped endwall, turbulence intensity has only mild effect on the film cooling effectiveness.

  4. Effect of turbulence intensity on cross-injection film cooling at a stepped or smooth endwall of a gas turbine vane passage.

    PubMed

    Wu, Pey-Shey; Tsai, Shen-Ta; Jhuo, Yue-Hua

    2014-01-01

    This study is concerned with a film cooling technique applicable to the protection of the endwalls of a gas turbine vane. In the experiments, cross-injection coolant flow from two-row, paired, inclined holes with nonintersecting centerlines was utilized. The test model is a scaled two-half vane. The levels of turbulence intensity used in the experiments are T.I. = 1.8%, 7%, and 12%. Other parameters considered in the film cooling experiments include three inlet Reynolds numbers (9.20 × 10(4), 1.24 × 10(5), and 1.50 × 10(5)), three blowing ratios (0.5, 1.0, and 2.0), and three endwall conditions (smooth endwall and stepped endwall with forward-facing or backward-facing step). Thermochromic liquid crystal (TLC) technique with steady-state heat transfer experiments was used to obtain the whole-field film cooling effectiveness. Results show that, at low turbulence intensity, increasing Reynolds number decreases the effectiveness in most of the vane passage. There is no monotonic trend of influence by Reynolds number at high turbulence intensity. The effect of blowing ratio on the effectiveness has opposite trends at low and high turbulence levels. Increasing turbulent intensity decreases the effectiveness, especially near the inlet of the vane passage. With a stepped endwall, turbulence intensity has only mild effect on the film cooling effectiveness. PMID:24592153

  5. Effect of Turbulence Intensity on Cross-Injection Film Cooling at a Stepped or Smooth Endwall of a Gas Turbine Vane Passage

    PubMed Central

    Tsai, Shen-Ta; Jhuo, Yue-Hua

    2014-01-01

    This study is concerned with a film cooling technique applicable to the protection of the endwalls of a gas turbine vane. In the experiments, cross-injection coolant flow from two-row, paired, inclined holes with nonintersecting centerlines was utilized. The test model is a scaled two-half vane. The levels of turbulence intensity used in the experiments are T.I. = 1.8%, 7%, and 12%. Other parameters considered in the film cooling experiments include three inlet Reynolds numbers (9.20 × 104, 1.24 × 105, and 1.50 × 105), three blowing ratios (0.5, 1.0, and 2.0), and three endwall conditions (smooth endwall and stepped endwall with forward-facing or backward-facing step). Thermochromic liquid crystal (TLC) technique with steady-state heat transfer experiments was used to obtain the whole-field film cooling effectiveness. Results show that, at low turbulence intensity, increasing Reynolds number decreases the effectiveness in most of the vane passage. There is no monotonic trend of influence by Reynolds number at high turbulence intensity. The effect of blowing ratio on the effectiveness has opposite trends at low and high turbulence levels. Increasing turbulent intensity decreases the effectiveness, especially near the inlet of the vane passage. With a stepped endwall, turbulence intensity has only mild effect on the film cooling effectiveness. PMID:24592153

  6. Horizontal tapping furnace and method of operation

    SciTech Connect

    Wunsche, E.R.

    1987-07-14

    A metallurgical furnace is described including: a furnace floor and a furnace wall means extending generally upwardly about the floor, the furnace having a vertical axis and a horizontal axis, means mounting the furnace for pivotal tilting movement about the horizontal axis between a non-tilted, normal upright position, and a tilted discharge position with the furnace tilted less than 15/sup 0/ to the vertical axis; a hearth zone defined between the floor and wall means adapted to house a bath of liquid metal of predetermined volume, the hearth zone having an upper end defining a predetermined upper level for the bath and for a layer of liquid slag floating on the upper level, when the furnace is in a non-tilted, normal upright position; the hearth zone having a lower end adjacent the floor, a tapping passage extending through the wall means from a liquid metal discharge outlet at an outer end into the lower end of the hearth zone, at an inner end, the discharge outlet being defined by an outwardly facing passage wall and the passage at the outer end; the tapping passage disposed generally parallel to the horizontal axis and vertically below the predetermined upper level, when the furnace is in the non-tilted, normal, upright position; a discharge outlet closure having a closure surface and pivotally mounted externally of the passage for pivotal to and for movement towards and away from the furnace wall means between a first position. The closure surface engages the passage wall at the outer end to fully close the discharge outlet, and a second position spaced apart from the passage wall.

  7. Does horizontal transmission invalidate cultural phylogenies?

    PubMed Central

    Greenhill, Simon J.; Currie, Thomas E.; Gray, Russell D.

    2009-01-01

    Phylogenetic methods have recently been applied to studies of cultural evolution. However, it has been claimed that the large amount of horizontal transmission that sometimes occurs between cultural groups invalidates the use of these methods. Here, we use a natural model of linguistic evolution to simulate borrowing between languages. The results show that tree topologies constructed with Bayesian phylogenetic methods are robust to realistic levels of borrowing. Inferences about divergence dates are slightly less robust and show a tendency to underestimate dates. Our results demonstrate that realistic levels of reticulation between cultures do not invalidate a phylogenetic approach to cultural and linguistic evolution. PMID:19324763

  8. In situ bioremediation using horizontal wells

    SciTech Connect

    1995-04-01

    In Situ Bioremediation (ISB), which is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation, remediates soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISB involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove .VOCs from the vadose zone concomitant with biodegradation of VOCs. The innovation is in the combination of 3 emerging technologies, air stripping, horizontal wells, and bioremediation via gaseous nutrient injection with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

  9. Impulse absorption by horizontal magnetic granular chain

    NASA Astrophysics Data System (ADS)

    Leng, Dingxin; Wang, Xiaojie; Liu, Guijie; Sun, Lingyu

    2016-02-01

    The granular medium is known as a protecting material for shock mitigation. We study the impulse absorption of an alignment of magnetic spheres placed horizontally under a non-uniform magnetic field. The phenomenon of the wave dispersion is presented. This system can absorb 85% ˜ 95% (88% ˜ 98%) of the incident peak force (energy) under the applied magnetic field strength in 0.1 T ˜ 1.0 T. The shock attenuation capacities are enhanced by the increment of field strength. With an intelligent control system, it is conceivable that the magnetic granular chain may offer possibilities in developing adaptive shock protectors.

  10. Does horizontal transmission invalidate cultural phylogenies?

    PubMed

    Greenhill, Simon J; Currie, Thomas E; Gray, Russell D

    2009-06-22

    Phylogenetic methods have recently been applied to studies of cultural evolution. However, it has been claimed that the large amount of horizontal transmission that sometimes occurs between cultural groups invalidates the use of these methods. Here, we use a natural model of linguistic evolution to simulate borrowing between languages. The results show that tree topologies constructed with Bayesian phylogenetic methods are robust to realistic levels of borrowing. Inferences about divergence dates are slightly less robust and show a tendency to underestimate dates. Our results demonstrate that realistic levels of reticulation between cultures do not invalidate a phylogenetic approach to cultural and linguistic evolution.

  11. Horizontal stability of a bouncing ball

    NASA Astrophysics Data System (ADS)

    McBennett, Brendan G.; Harris, Daniel M.

    2016-09-01

    We present an investigation of a partially elastic ball bouncing on a vertically vibrated concave parabolic surface in two dimensions. In particular, we demonstrate that simple vertical motion, wherein the ball bounces periodically at the parabola's vertex, is unstable to horizontal perturbations when the parabolic coefficient defining the surface shape exceeds a critical value. The result is a new periodic solution where the ball bounces laterally over the vertex. As the parabola is further steepened, this new solution also becomes unstable which gives rise to other complex periodic and chaotic bouncing states, all characterized by persistent lateral motion.

  12. Effect of a horizontal plane boundary on a falling horizontal cylinder at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Chen, Y.-J.; Hussey, R. G.

    1980-05-01

    Experimental results are presented for the change in velocity of a slender cylinder with its axis horizontal as it falls through a viscous fluid toward a horizontal plane boundary. When the boundary influence is strong, the deceleration of the cylinder is observed to be constant, and the velocity extrapolates to zero at the boundary. When the relative change in velocity is small (less than 20%), it is observed to depend inversely on the square of the distance from the boundary. The Reynolds number based on cylinder diameter ranges from 2.9 to 0.015 and the Reynolds number based on cylinder length ranges from 122 to 0.16.

  13. New photolithography stepping machine

    SciTech Connect

    Hale, L.; Klingmann, J.; Markle, D.

    1995-03-08

    A joint development project to design a new photolithography steeping machine capable of 150 nanometer overlay accuracy was completed by Ultratech Stepper and the Lawrence Livermore National Laboratory. The principal result of the project is a next-generation product that will strengthen the US position in step-and-repeat photolithography. The significant challenges addressed and solved in the project are the subject of this report. Design methods and new devices that have broader application to precision machine design are presented in greater detail while project specific information serves primarily as background and motivation.

  14. Steps to the moon

    USGS Publications Warehouse

    ,; Dale, Alvin E.

    1976-01-01

    On July 20, 1969, man walked on the surface of the Moon and began a new chapter of his studies that will eventually disclose the geologic nature of the Earth's nearest neighbor. Although he has finally reached the Moon and sampled its substance, much work and study remain before he will know the full scientific significance of the first landing. This booklet briefly summarizes the steps man has taken to understand the Moon and what he thinks he has learned to date as a result of his centuries-long speculations and studies.

  15. Experimentation: the next step

    PubMed Central

    Marinker, Marshall

    1987-01-01

    General practice has entered a period of accelerating change, and those responsible for planning its development now put forward a variety of promising proposals. Unless provision is made for large scale experimentation and scientific evaluation, the direction of future change will be determined not by evidence but by rhetoric. A framework for creating and evaluating a substantial programme of experimentation is suggested. The programme is the logical next step in the process of change which was given impetus by the publication of the government green paper. It should be seen as a professional, moral and political priority. PMID:3681850

  16. Generation of Large-Scale Winds in Horizontally Anisotropic Convection.

    PubMed

    von Hardenberg, J; Goluskin, D; Provenzale, A; Spiegel, E A

    2015-09-25

    We simulate three-dimensional, horizontally periodic Rayleigh-Bénard convection, confined between free-slip horizontal plates and rotating about a distant horizontal axis. When both the temperature difference between the plates and the rotation rate are sufficiently large, a strong horizontal wind is generated that is perpendicular to both the rotation vector and the gravity vector. The wind is turbulent, large-scale, and vertically sheared. Horizontal anisotropy, engendered here by rotation, appears necessary for such wind generation. Most of the kinetic energy of the flow resides in the wind, and the vertical turbulent heat flux is much lower on average than when there is no wind. PMID:26451558

  17. Horizontal coherence in the NPAL experiment

    NASA Astrophysics Data System (ADS)

    Vera, Michael; Dzieciuch, Matthew

    2001-05-01

    Acoustic transmissions from a broadband source near Kauai with a center frequency of 75 Hz were recorded on a two-dimensional receiver array at a range of 3900 km as part of the North Pacific Acoustic Laboratory (NPAL) experiment. The receiver array consisted of five vertical line arrays (VLAs), with separations transverse to the propagation path ranging from a few hundred meters to a few kilometers. The coherences derived from the data have been compared to two different numerical predictions based on sound-speed perturbations due to internal waves. An approximation to the acoustic path integral yields a prediction for the length scale of horizontal coherence. Parabolic-equation simulations of propagation from the source to each VLA through multiple realizations of a random internal-wave field provide another estimate of the coherence at each horizontal separation. [Work supported by ONR.] a)J. A. Colosi, B. D. Cornuelle, B. D. Dushaw, M. A. Dzieciuch, B. M. Howe, J. A. Mercer, R. C. Spindel, and P. F. Worcester.

  18. Reservoir visualization for geosteering of horizontal wells

    SciTech Connect

    Bryant, I.D.; Baygun, B.; Frass, M.; Casco, R.

    1996-08-01

    Horizontal infill wells in the Lower Lagunillas reservoir of Bloque IV, Lake Maracaibo are being drilled in thin, oil-bearing zones that have been bypassed by gas. Steering the horizontal sections of these wells requires high resolution reservoir models that can be updated during drilling. An example from well VLD-1152 serves to illustrate how these models are generated and used. Resistivity images collected by wireline and logging-while-drilling (LWD) tools in the pilot well formed the basis of prejob, high resolution modeling of the formation properties. 3-D seismic data and data from an offset vertical seismic profile collected in the pilot well provided the structural model. During drilling information from cuttings and LWD tools was used to continuously update these models. After the well had been drilled, analysis of LWD resistivity images provided a detailed model of the relationship between the well trajectory and the dip of the formation. This information is used to improve interpretation of the LWD logs to provide a petrophysical evaluation of the well.

  19. Horizontal Air Bearing Experiment Number 1

    SciTech Connect

    Clauson, T.L.

    1999-08-31

    The Horizontal Air Bearing Experiment No.1 is a series of tests intended to further the understanding of rotational dynamics. A simple experimental assembly is rotated using the Horizontal Air Bearing and allowed to spin freely as the internal rotational damping is measured. The low friction of the bearing effectively isolates the test assembly, allowing the internal damping of the test object to be evaluated. The experimental assembly is composed of an aluminum ball within a spherical cavity. A flanged pipe section and an auxiliary adapter plate secure the assembly to the Air Bearing interface plate. Three aluminum balls are interchanged to vary test parameters. The aluminum balls are free to move independently as the entire assembly rotates. The aluminum balls vary in diameter and/or surface finish. While the diameter and surface finish is varied, the space between the ball and socket is dry. To examine the effect of viscosity, the space is filled with a lubricant while the ball diameter and surface finish is held constant.

  20. SPAR-H Step-by-Step Guidance

    SciTech Connect

    W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

    2011-05-01

    This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

  1. Stair-stepped Mound

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-429, 22 July 2003

    This April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a stair-stepped mound of sedimentary rock (right of center) on the floor of a large impact crater in western Arabia Terra near 11.0oN, 4.4oW. Sedimentary rock outcrops are common in the craters of this region. The repeated thickness and uniformity of the layers that make up this mound suggest that their depositional environment was one in which cyclic or episodic events occurred over some period of time. The sediments might have been deposited in a lake, or they may have settled directly out of the atmosphere. Most of the layered material was later eroded away, leaving this circular mound and the other nearby mesas and knobs. The image is illuminated by sunlight from the lower left.

  2. Intense turbulent convection in a horizontal plane liquid layer

    NASA Astrophysics Data System (ADS)

    Gertsenshtein, S. Ya.; Palymskii, I. A.; Sibgatullin, I. N.

    2008-02-01

    Direct numerical simulation of turbulent convection in a horizontal liquid layer heated from below is performed within the framework of the nonstationary Navier—Stokes equations with the use of the Bubnov—Galerkin method. The main attention is given to calculations for superhigh supercriticalities. Computational burden is reduced by the use of the splitting method at each step of integration. Previously, the smallness of the residual arising from substitution of simulated results into the initial system of equations is demonstrated and the residual’s dependence on the number of reference functions and supercriticality is considered. A good agreement of the results obtained with the use of different numerical implementations of the Bubnov—Galerkin procedure is shown, in particular, for the stochastic processes corresponding to a low supercriticality and appearing with the formation of strange attractors close to a Mobius strip. The calculations were carried out for a wide range of supercriticality (from 1 to 34000). It is shown that simulations and experiment are in good qualitative agreement.

  3. Step bunching and ordering induced by step-edge barriers

    NASA Astrophysics Data System (ADS)

    Zhao, Yuegang; Liu, Feng; Tersoff, Jerry; Lagally, Max G.

    2000-03-01

    We derive the equation of motion of steps for step flow growth under the influence of both misfit strain and step-edge barriers. An energy barrier at a step for an atom arriving from the lower terrace causes a step bunching instability. Simulation results show that the bunching is predominantly driven by a coalescence mechanism, leading to multiple transient stages of metastable step bunch arrays, with average bunch size of 2, 4, and 8 steps. The bunch array in these transient stages exhibits a surprisingly good long-range order. Similar kinetic step-bunch ordering has been seen in a a recent experiment[1]. Reference: [1]: C. Schelling, G. Springholz, and F. Schäffler, Phys. Rev. Letts, 83(995)1999.

  4. Horizontal Gene Transfer, Dispersal and Haloarchaeal Speciation

    PubMed Central

    Papke, R. Thane; Corral, Paulina; Ram-Mohan, Nikhil; de la Haba, Rafael R.; Sánchez-Porro, Cristina; Makkay, Andrea; Ventosa, Antonio

    2015-01-01

    The Halobacteria are a well-studied archaeal class and numerous investigations are showing how their diversity is distributed amongst genomes and geographic locations. Evidence indicates that recombination between species continuously facilitates the arrival of new genes, and within species, it is frequent enough to spread acquired genes amongst all individuals in the population. To create permanent independent diversity and generate new species, barriers to recombination are probably required. The data support an interpretation that rates of evolution (e.g., horizontal gene transfer and mutation) are faster at creating geographically localized variation than dispersal and invasion are at homogenizing genetic differences between locations. Therefore, we suggest that recurrent episodes of dispersal followed by variable periods of endemism break the homogenizing forces of intrapopulation recombination and that this process might be the principal stimulus leading to divergence and speciation in Halobacteria. PMID:25997110

  5. Passive magnetic bearing for a horizontal shaft

    DOEpatents

    Post, Richard F.

    2003-12-02

    A passive magnetic bearing is composed of a levitation element and a restorative element. The levitation element is composed of a pair of stationary arcuate ferromagnetic segments located within an annular radial-field magnet array. The magnet array is attached to the inner circumference of a hollow shaft end. An attractive force between the arcuate segments and the magnet array acts vertically to levitate the shaft, and also in a horizontal transverse direction to center the shaft. The restorative element is comprised of an annular Halbach array of magnets and a stationary annular circuit array located within the Halbach array. The Halbach array is attached to the inner circumference of the hollow shaft end. A repulsive force between the Halbach array and the circuit array increases inversely to the radial space between them, and thus acts to restore the shaft to its equilibrium axis of rotation when it is displaced therefrom.

  6. Conjugate natural convection between horizontal eccentric cylinders

    NASA Astrophysics Data System (ADS)

    Nasiri, Davood; Dehghan, Ali Akbar; Hadian, Mohammad Reza

    2016-06-01

    This study involved the numerical investigation of conjugate natural convection between two horizontal eccentric cylinders. Both cylinders were considered to be isothermal with only the inner cylinder having a finite wall thickness. The momentum and energy equations were discretized using finite volume method and solved by employing SIMPLER algorithm. Numerical results were presented for various solid-fluid conductivity ratios (KR) and various values of eccentricities in different thickness of inner cylinder wall and also for different angular positions of inner cylinder. From the results, it was observed that in an eccentric case, and for KR < 10, an increase in thickness of inner cylinder wall resulted in a decrease in the average equivalent conductivity coefficient (overline{{K_{eq} }} ); however, a KR > 10 value caused an increase in overline{{K_{eq} }} . It was also concluded that in any angular position of inner cylinder, the value of overline{{K_{eq} }} increased with increase in the eccentricity.

  7. Horizontal Drop of 21- PWR Waste Package

    SciTech Connect

    A.K. Scheider

    2007-01-31

    The objective of this calculation is to determine the structural response of the waste package (WP) dropped horizontally from a specified height. The WP used for that purpose is the 21-Pressurized Water Reactor (PWR) WP. The scope of this document is limited to reporting the calculation results in-terms of stress intensities. This calculation is associated with the WP design and was performed by the Waste Package Design group in accordance with the ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 16). AP-3.12Q, ''Calculations'' (Ref. 1 1) is used to perform the calculation and develop the document. The sketches attached to this calculation provide the potential dimensions and materials for the 21-PWR WP design.

  8. Horizontal Gene Exchange in Environmental Microbiota

    PubMed Central

    Aminov, Rustam I.

    2011-01-01

    Horizontal gene transfer (HGT) plays an important role in the evolution of life on the Earth. This view is supported by numerous occasions of HGT that are recorded in the genomes of all three domains of living organisms. HGT-mediated rapid evolution is especially noticeable among the Bacteria, which demonstrate formidable adaptability in the face of recent environmental changes imposed by human activities, such as the use of antibiotics, industrial contamination, and intensive agriculture. At the heart of the HGT-driven bacterial evolution and adaptation are highly sophisticated natural genetic engineering tools in the form of a variety of mobile genetic elements (MGEs). The main aim of this review is to give a brief account of the occurrence and diversity of MGEs in natural ecosystems and of the environmental factors that may affect MGE-mediated HGT. PMID:21845185

  9. Method for horizontally growing ribbon crystal

    NASA Technical Reports Server (NTRS)

    Kudo, B.

    1980-01-01

    A high speed method for forming ribbon crystal of desired width and thickness is characterized by drawing out the ribbon through a space whose distance is 5.7 times that of the thickness of the grown ribbon. The ribbon is drawn out between the molten body of the lower surface and the tip of the upper surface of the seed crystal and growing crystal. The ribbon growing at the tip of the seed crystal is drawn out horizontally and centrifugally by controlling the amount of cooling and heating. The temperature is maintained about equal to the upper surface of the outlets from which the molten substance is drawn, at least in certain portions of the crucible rim, the rim is elevated to prevent dropping of the molten raw material.

  10. Horizontal gene transfer, dispersal and haloarchaeal speciation.

    PubMed

    Papke, R Thane; Corral, Paulina; Ram-Mohan, Nikhil; Haba, Rafael R de la; Sánchez-Porro, Cristina; Makkay, Andrea; Ventosa, Antonio

    2015-01-01

    The Halobacteria are a well-studied archaeal class and numerous investigations are showing how their diversity is distributed amongst genomes and geographic locations. Evidence indicates that recombination between species continuously facilitates the arrival of new genes, and within species, it is frequent enough to spread acquired genes amongst all individuals in the population. To create permanent independent diversity and generate new species, barriers to recombination are probably required. The data support an interpretation that rates of evolution (e.g., horizontal gene transfer and mutation) are faster at creating geographically localized variation than dispersal and invasion are at homogenizing genetic differences between locations. Therefore, we suggest that recurrent episodes of dispersal followed by variable periods of endemism break the homogenizing forces of intrapopulation recombination and that this process might be the principal stimulus leading to divergence and speciation in Halobacteria. PMID:25997110

  11. Large, horizontal-axis wind turbines

    NASA Technical Reports Server (NTRS)

    Linscott, B. S.; Perkins, P.; Dennett, J. T.

    1984-01-01

    Development of the technology for safe, reliable, environmentally acceptable large wind turbines that have the potential to generate a significant amount of electricity at costs competitive with conventional electric generating systems are presented. In addition, these large wind turbines must be fully compatible with electric utility operations and interface requirements. There are several ongoing large wind system development projects and applied research efforts directed toward meeting the technology requirements for utility applications. Detailed information on these projects is provided. The Mod-O research facility and current applied research effort in aerodynamics, structural dynamics and aeroelasticity, composite and hybrid composite materials, and multiple system interaction are described. A chronology of component research and technology development for large, horizontal axis wind turbines is presented. Wind characteristics, wind turbine economics, and the impact of wind turbines on the environment are reported. The need for continued wind turbine research and technology development is explored. Over 40 references are sited and a bibliography is included.

  12. Horizontal Hostility among Non-Meat Eaters

    PubMed Central

    Rothgerber, Hank

    2014-01-01

    The present study examined intergroup judgments made between four groups of non-meat eaters: health vegetarians; ethical vegetarians; health vegans, and ethical vegans. Consistent with hypotheses based on horizontal hostility and the need to maintain ingroup distinctiveness, ethical vegetarians gave unfavorable evaluations to health vegetarians relative to vegans, especially when the mainstream omnivore group was made salient. Contrary to expectations, vegans gave relatively more favorable evaluations to ethical vegetarians than health vegetarians when mainstream salience was low. This was especially true for vegans who were motivated primarily by ethical concerns. When mainstream salience was high, vegans did not distinguish between the vegetarian subgroups. Results suggest that one’s motives for abstaining from meat often play a larger role in this type of intergroup perceptions than one’s dietary practices. PMID:24809342

  13. Horizontal gene transfer: A critical view

    PubMed Central

    Kurland, C. G.; Canback, B.; Berg, Otto G.

    2003-01-01

    It has been suggested that horizontal gene transfer (HGT) is the “essence of phylogeny.” In contrast, much data suggest that this is an exaggeration resulting in part from a reliance on inadequate methods to identify HGT events. In addition, the assumption that HGT is a ubiquitous influence throughout evolution is questionable. Instead, rampant global HGT is likely to have been relevant only to primitive genomes. In modern organisms we suggest that both the range and frequencies of HGT are constrained most often by selective barriers. As a consequence those HGT events that do occur most often have little influence on genome phylogeny. Although HGT does occur with important evolutionary consequences, classical Darwinian lineages seem to be the dominant mode of evolution for modern organisms. PMID:12902542

  14. Green Schools Energy Project: A Step-by-Step Manual.

    ERIC Educational Resources Information Center

    Quigley, Gwen

    This publication contains a step-by-step guide for implementing an energy-saving project in local school districts: the installation of newer, more energy-efficient "T-8" fluorescent tube lights in place of "T-12" lights. Eleven steps are explained in detail: (1) find out what kind of lights the school district currently uses; (2) form a group to…

  15. Experimental study of evaporation of horizontal films of water-salt solutions

    NASA Astrophysics Data System (ADS)

    Elistratov, S. L.; Morozov, V. S.

    2015-01-01

    The present studies were carried out for the horizontal films (thin layers) of water and water solutions of NaCl, CaCl2, LiCl, and LiBr with different solubility characteristics, as well as with specific features of formation and decay of water hydrates. Required volume of solution Vo of given weight concentration ξo, preliminary heated to the working surface temperature, was put in one step on the horizontal bottom of the bowl, heated to working temperature tCT, by means of volume batchers Thermo Scientific. After evaporation completion, the final mass of solution and form of their residue were registered. At the final stage of evaporation formation of NaCl crystals and water hydrates of CaCl2 · 2H2O, LiCl · H2O, and LiBr · 2H2O occurred.

  16. How important is randomisation in a stepped wedge trial?

    PubMed

    Hargreaves, James R; Prost, Audrey; Fielding, Katherine L; Copas, Andrew J

    2015-01-01

    In cluster randomised trials, randomisation increases internal study validity. If enough clusters are randomised, an unadjusted analysis should be unbiased. If a smaller number of clusters are included, stratified or matched randomisation can increase comparability between trial arms. In addition, an adjusted analysis may be required; nevertheless, randomisation removes the possibility for systematically biased allocation and increases transparency. In stepped wedge trials, clusters are randomised to receive an intervention at different start times ('steps'), and all clusters eventually receive it. In a recent study protocol for a 'modified stepped wedge trial', the investigators considered randomisation of the clusters (hospital wards), but decided against it for ethical and logistical reasons, and under the assumption that it would not add much to the rigour of the evaluation. We show that the benefits of randomisation for cluster randomised trials also apply to stepped wedge trials. The biggest additional issue for stepped wedge trials in relation to parallel cluster randomised trials is the need to control for secular trends in the outcome. Analysis of stepped wedge trials can in theory be based on 'horizontal' or 'vertical' comparisons. Horizontal comparisons are based on measurements taken before and after the intervention is introduced in each cluster, and are unbiased if there are no secular trends. Vertical comparisons are based on outcome measurements from clusters that have switched to the intervention condition and those from clusters that have yet to switch, and are unbiased under randomisation since at any time point, which clusters are in intervention and control conditions will have been determined at random. Secular outcome trends are a possibility in many settings. Many stepped wedge trials are analysed with a mixed model, including a random effect for cluster and fixed effects for time period to account for secular trends, thereby combining both

  17. 1992 STEP Symposium

    NASA Astrophysics Data System (ADS)

    Lui, Tony

    The year 1992 marks the quincentenary jubilee of the famous voyage of Christopher Columbus to the New World, a trip which initiated sustained contact between Europe and the American continent. Courageous explorations often lead to advancement of mankind, be they in uncharted territory or science. As much as Columbus was unaware of what lay in store for his voyage, we were just as poorly informed about what lay beyond our home planet when we began space exploration about three decades ago. There is much similarity among the pioneering spirits characteristic of both endeavors. It is thus fitting to celebrate this quincentenary occasion by declaring 1992 International Space Year (ISY).In conjunction with the COSPAR Meeting and the International Convention of the World Space Congress to be held in Washington, D.C., from August to September 1992, a 4-day symposium on the initial results from the Solar-Terrestrial Energy Program (STEP) Facilities and Theory Campaigns will be held at Johns Hopkins University, Applied Physics Laboratory, Laurel, Md., August 24-27. 1992.

  18. Dopamine D1 receptor modulation of calcium channel currents in horizontal cells of mouse retina.

    PubMed

    Liu, Xue; Grove, James C R; Hirano, Arlene A; Brecha, Nicholas C; Barnes, Steven

    2016-08-01

    Horizontal cells form the first laterally interacting network of inhibitory interneurons in the retina. Dopamine released onto horizontal cells under photic and circadian control modulates horizontal cell function. Using isolated, identified horizontal cells from a connexin-57-iCre × ROSA26-tdTomato transgenic mouse line, we investigated dopaminergic modulation of calcium channel currents (ICa) with whole cell patch-clamp techniques. Dopamine (10 μM) blocked 27% of steady-state ICa, an action blunted to 9% in the presence of the L-type Ca channel blocker verapamil (50 μM). The dopamine type 1 receptor (D1R) agonist SKF38393 (20 μM) inhibited ICa by 24%. The D1R antagonist SCH23390 (20 μM) reduced dopamine and SKF38393 inhibition. Dopamine slowed ICa activation, blocking ICa by 38% early in a voltage step. Enhanced early inhibition of ICa was eliminated by applying voltage prepulses to +120 mV for 100 ms, increasing ICa by 31% and 11% for early and steady-state currents, respectively. Voltage-dependent facilitation of ICa and block of dopamine inhibition after preincubation with a Gβγ-blocking peptide suggested involvement of Gβγ proteins in the D1R-mediated modulation. When the G protein activator guanosine 5'-O-(3-thiotriphosphate) (GTPγS) was added intracellularly, ICa was smaller and showed the same slowed kinetics seen during D1R activation. With GTPγS in the pipette, additional block of ICa by dopamine was only 6%. Strong depolarizing voltage prepulses restored the GTPγS-reduced early ICa amplitude by 36% and steady-state ICa amplitude by 3%. These results suggest that dopaminergic inhibition of ICa via D1Rs is primarily mediated through the action of Gβγ proteins in horizontal cells. PMID:27193322

  19. STEPS: JPL's Astrometric Exoplanet Survey

    NASA Technical Reports Server (NTRS)

    Shaklan, Stuart; Pravdo, Steve

    2008-01-01

    Presentation topics include: STEPS ground-based astrometry at Hale Telescope; the instrument; why astronomy and why M-dwarfs; motion of center of light about center of mass in photocentric orbit; photocentric motion vs. fractional mass; high-resolution imaging of STEPS targets; GU 802 p one possible orbit plotted with data, Keplerian frame; GJ 802 results; STEPS future; and a bibliography of STEPS papers.

  20. SPAR-H Step-by-Step Guidance

    SciTech Connect

    April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

    2012-06-01

    Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

  1. Multiple stage miniature stepping motor

    DOEpatents

    Niven, William A.; Shikany, S. David; Shira, Michael L.

    1981-01-01

    A stepping motor comprising a plurality of stages which may be selectively activated to effect stepping movement of the motor, and which are mounted along a common rotor shaft to achieve considerable reduction in motor size and minimum diameter, whereby sequential activation of the stages results in successive rotor steps with direction being determined by the particular activating sequence followed.

  2. Powerlessness Reinterpreted: Reframing Step One.

    ERIC Educational Resources Information Center

    Young, Susan L.

    The 12 steps of the well-known mutual help group, Alcoholics Anonymous (AA), begin with Step One, admitting powerlessness. Although Step One has helped many problem drinkers and other addicts, its spiritual concepts have been criticized. The possibility of reconceptualizing powerlessness as empowering, not only within AA and its offshoot programs,…

  3. Demonstration of a utility industry horizontal drilling system: Horizontal well AMH-5 installation report

    SciTech Connect

    Not Available

    1992-12-31

    The Department of Energy`s Office of Technology Development initiated an integrated demonstration of innovative technologies and systems for cleanup of VOCs in soils and groundwater at the Savannah River Site (SRS) in 1989. The overall goal of the program is demonstration of multiple technologies and systems in the fields of drilling, characterization, monitoring, and remediation at a single test bed. Innovative technologies are compared to one another and to baseline technologies in terms of technical performance and cost effectiveness. Transfer of successfully demonstrated technologies and systems to DOE environmental restoration organizations, to other government agencies, and to industry is a critical part of the program. Directional drilling has been shown to be a successful technique for enhancing access to the subsurface, thus improving remediation systems, especially remediation systems which perform in situ. Demonstration of an innovative directional drilling system at the Integrated Demonstration Site at the SRS, was initiated in June of 1992. The directional drilling system was designed to install an in situ remediation system. The drilling system is an experimental compaction/dry drilling technique developed by Charles Machine Works (Ditch Witch{reg_sign}) of Perry, Oklahoma. A horizontal well was installed in the M Area of the SRS below and parallel to an abandoned tile process sewer line. The installation of the horizontal well was a two-part process. Part one consisted of drilling the borehole, and part two was the horizontal well completion.

  4. Evaluation of global horizontal irradiance to plane-of-array irradiance models at locations across the United States

    SciTech Connect

    Lave, Matthew; Hayes, William; Pohl, Andrew; Hansen, Clifford W.

    2015-02-02

    We report an evaluation of the accuracy of combinations of models that estimate plane-of-array (POA) irradiance from measured global horizontal irradiance (GHI). This estimation involves two steps: 1) decomposition of GHI into direct and diffuse horizontal components and 2) transposition of direct and diffuse horizontal irradiance (DHI) to POA irradiance. Measured GHI and coincident measured POA irradiance from a variety of climates within the United States were used to evaluate combinations of decomposition and transposition models. A few locations also had DHI measurements, allowing for decoupled analysis of either the decomposition or the transposition models alone. Results suggest that decomposition models had mean bias differences (modeled versus measured) that vary with climate. Transposition model mean bias differences depended more on the model than the location. Lastly, when only GHI measurements were available and combinations of decomposition and transposition models were considered, the smallest mean bias differences were typically found for combinations which included the Hay/Davies transposition model.

  5. Step-step interactions on GaAs (110) nanopatterns

    SciTech Connect

    Galiana, B.; Benedicto, M.; Tejedor, P.

    2013-01-14

    The step-step interactions on vicinal GaAs (110) surface patterns have been extracted from the quantitative analysis of the terrace width distribution (TWD). We have specifically studied the interactions in near-equilibrium faceting and kinetics-driven step bunching and meandering formed by spontaneous self-organization or through the modification of GaAs growth kinetics by atomic hydrogen. We show that the experimental TWDs determined from atomic force microscopy measurements can be accurately described by a weighed sum of a generalized Wigner distribution and several Gaussians. The results of our calculations indicate that straight facets are formed during high temperature homoepitaxy due to attractive interactions between [110] steps. At low temperatures, steady state attractive interactions in [110] step bunches are preceded by a transition regime dominated by entropic and energetic repulsions between meandering [11n]-type steps (n {>=} 2), whose population density exceeds that of the [110] bunched steps. In addition, it has been found that atomic H reduces the attractive interactions between [110] bunched steps and enhances entropic and dipole-induced energetic repulsions between H-terminated [11n] steps through the inhibition of As-As bond formation at step edges. Our analysis has evidenced a correlation between the value of the adjustable parameter that accounts in our model for the specific weight of the secondary peaks in the TWD ({beta}) and the extent of transverse meandering on the vicinal surface.

  6. New solutions for the confined horizontal aquifer

    NASA Astrophysics Data System (ADS)

    Akylas, Evangelos; Gravanis, Elias

    2016-04-01

    The Boussinesq equation is a dynamical equation for the free surface of saturated subsurface flows over an impervious bed. Boussinesq equation is non-linear. The non-linearity comes from the reduction of the dimensionality of the problem: The flow is assumed to be vertically homogeneous, therefore the flow rate through a cross section of the flow is proportional to the free surface height times the hydraulic gradient, which is assumed to be equal to the slope of the free surface. In the present work we consider the case of the subsurface flow with horizontal bed. This is a case with an infinite Henderson and Wooding parameter, that is, it is the limiting case where the non-linear term is present in the Boussinesq equation while the linear spatial derivative term vanishes. Nonetheless, no analogue of the kinematic wave exists in this case as there is no exact solution for the build-up phase. Neither is there an exact recession-phase solution that holds in early times, as the Boussinesq separable solution is actually an asymptotic solution for large times. We construct approximate solutions for the horizontal aquifer which utilize directly the dynamical content of the non-linear Boussinesq equation. The approximate character of the solution lies in the fact that we start with a pre-supposed form for the solution, an educated guess, based on the nature of the initial condition as well as empirical observations from the numerical solution of the problem. The forms we shall use are power series of the location variable x along the bed with time-dependent coefficients. The series are not necessarily analytic. The boundary conditions are incorporated in the structure of the series from the beginning. The time-dependent coefficients are then determined by applying the Boussinesq equation and its spatial derivatives at the end-points of the aquifer. The forms are chosen also on the basis of their solubility; we would like to be able to construct explicitly the approximate

  7. Shallow water model for horizontal centrifugal casting

    NASA Astrophysics Data System (ADS)

    Boháček, J.; Kharicha, A.; Ludwig, A.; Wu, M.

    2012-07-01

    A numerical model was proposed to simulate the solidification process of an outer shell of work roll made by the horizontal centrifugal casting technique. Shallow water model was adopted to solve the 2D average flow dynamics of melt spreading and the average temperature distribution inside the centrifugal casting mould by considering the centrifugal force, Coriolis force, viscous force due to zero velocity on the mould wall, gravity, and energy transport by the flow. Additionally, a 1D sub-model was implemented to consider the heat transfer in the radial direction from the solidifying shell to the mould. The solidification front was tracked by fulfilling the Stefan condition. Radiative and convective heat losses were included from both, the free liquid surface and the outer wall of the mould. Several cases were simulated with the following assumed initial conditions: constant height of the liquid metal (10, 20, and 30 mm), uniform temperature of the free liquid surface (1755 K). The simulation results have shown that while the solidification front remained rather flat, the free surface was disturbed by waves. The amplitude of waves increased with the liquid height. Free surface waves diminished as the solidification proceeded.

  8. Magneto-convective instabilities in horizontal cavities

    NASA Astrophysics Data System (ADS)

    Mistrangelo, Chiara; Bühler, Leo

    2016-02-01

    A linear stability analysis is performed to investigate the onset of convective motions in a flat cavity filled with liquid metal. A volumetric heat source is uniformly distributed in the fluid and a horizontal magnetic field is imposed. Walls perpendicular to the magnetic field are thermally insulating, and the top wall is isothermal and the bottom adiabatic. When a magnetic field is applied, electromagnetic forces tend to transform 3D convective flow structures into quasi-2D rolls aligned to the magnetic field. By integrating 3D equations along magnetic field lines, a quasi-2D mathematical model has been derived. A dissipation term in the 2D equations accounts for 3D viscous effects in boundary layers at Hartmann walls perpendicular to the magnetic field. The influence of various parameters on flow stability is investigated. The flow is stabilized by increasing the magnetic field intensity or the electric conductance of Hartmann walls and by reducing the aspect ratio of the cavity. Numerical simulations are performed to verify the analytical results and to describe the main convective flow patterns in the non-linear regime.

  9. Yaw dynamics of horizontal axis wind turbines

    SciTech Connect

    Hansen, A.C. )

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  10. Film condensation in a horizontal rectangular duct

    NASA Technical Reports Server (NTRS)

    Lu, Qing; Suryanarayana, N. V.

    1992-01-01

    Condensation heat transfer in an annular flow regime with and without interfacial waves was experimentally investigated. The study included measurements of heat transfer rate with condensation of vapor flowing inside a horizontal rectangular duct and experiments on the initiation of interfacial waves in condensation, and adiabatic air-liquid flow. An analytical model for the condensation was developed to predict condensate film thickness and heat transfer coefficients. Some conclusions drawn from the study are that the condensate film thickness was very thin (less than 0.6 mm). The average heat transfer coefficient increased with increasing the inlet vapor velocity. The local heat transfer coefficient decreased with the axial distance of the condensing surface, with the largest change at the leading edge of the test section. The interfacial shear stress, which consisted of the momentum shear stress and the adiabatic shear stress, appeared to have a significant effect on the heat transfer coefficients. In the experiment, the condensate flow along the condensing surface experienced a smooth flow, a two-dimensional wavy flow, and a three-dimensional wavy flow. In the condensation experiment, the local wave length decreased with the axial distance of the condensing surface and the average wave length decreased with increasing inlet vapor velocity, while the wave speed increased with increasing vapor velocity. The heat transfer measurements are reliable. And, the ultrasonic technique was effective for measuring the condensate film thickness when the surface was smooth or had waves of small amplitude.

  11. Maximal liquid bridges between horizontal cylinders

    NASA Astrophysics Data System (ADS)

    Cooray, Himantha; Huppert, Herbert E.; Neufeld, Jerome A.

    2016-08-01

    We investigate two-dimensional liquid bridges trapped between pairs of identical horizontal cylinders. The cylinders support forces owing to surface tension and hydrostatic pressure that balance the weight of the liquid. The shape of the liquid bridge is determined by analytically solving the nonlinear Laplace-Young equation. Parameters that maximize the trapping capacity (defined as the cross-sectional area of the liquid bridge) are then determined. The results show that these parameters can be approximated with simple relationships when the radius of the cylinders is small compared with the capillary length. For such small cylinders, liquid bridges with the largest cross-sectional area occur when the centre-to-centre distance between the cylinders is approximately twice the capillary length. The maximum trapping capacity for a pair of cylinders at a given separation is linearly related to the separation when it is small compared with the capillary length. The meniscus slope angle of the largest liquid bridge produced in this regime is also a linear function of the separation. We additionally derive approximate solutions for the profile of a liquid bridge, using the linearized Laplace-Young equation. These solutions analytically verify the above-mentioned relationships obtained for the maximization of the trapping capacity.

  12. Horizontal visibility graphs from integer sequences

    NASA Astrophysics Data System (ADS)

    Lacasa, Lucas

    2016-09-01

    The horizontal visibility graph (HVG) is a graph-theoretical representation of a time series and builds a bridge between dynamical systems and graph theory. In recent years this representation has been used to describe and theoretically compare different types of dynamics and has been applied to characterize empirical signals, by extracting topological features from the associated HVGs which have shown to be informative on the class of dynamics. Among some other measures, it has been shown that the degree distribution of these graphs is a very informative feature that encapsulates nontrivial information of the series's generative dynamics. In particular, the HVG associated to a bi-infinite real-valued series of independent and identically distributed random variables is a universal exponential law P(k)=(1/3){(2/3)}k-2, independent of the series marginal distribution. Most of the current applications have however only addressed real-valued time series, as no exact results are known for the topological properties of HVGs associated to integer-valued series. In this paper we explore this latter situation and address univariate time series where each variable can only take a finite number n of consecutive integer values. We are able to construct an explicit formula for the parametric degree distribution {P}n(k), which we prove to converge to the continuous case for large n and deviates otherwise. A few applications are then considered.

  13. Horizontal Shear Wave Imaging of Large Optics

    SciTech Connect

    Quarry, M J

    2007-09-05

    When complete the National Ignition Facility (NIF) will be the world's largest and most energetic laser and will be capable of achieving for the first time fusion ignition in the laboratory. Detecting optics features within the laser beamlines and sizing them at diameters of 0.1 mm to 10 mm allows timely decisions concerning refurbishment and will help with the routine operation of the system. Horizontally polarized shear waves at 10 MHz were shown to accurately detect, locate, and size features created by laser operations from 0.5 mm to 8 mm by placing sensors at the edge of the optic. The shear wave technique utilizes highly directed beams. The outer edge of an optic can be covered with shear wave transducers on four sides. Each transducer sends a pulse into the optic and any damage reflects the pulse back to the transmitter. The transducers are multiplexed, and the collected time waveforms are enveloped and replicated across the width of the element. Multiplying the data sets from four directions produces a map of reflected amplitude to the fourth power, which images the surface of the optic. Surface area can be measured directly from the image, and maximum depth was shown to be correlated to maximum amplitude of the reflected waveform.

  14. Short‐term time step convergence in a climate model

    PubMed Central

    Rasch, Philip J.; Taylor, Mark A.; Jablonowski, Christiane

    2015-01-01

    Abstract This paper evaluates the numerical convergence of very short (1 h) simulations carried out with a spectral‐element (SE) configuration of the Community Atmosphere Model version 5 (CAM5). While the horizontal grid spacing is fixed at approximately 110 km, the process‐coupling time step is varied between 1800 and 1 s to reveal the convergence rate with respect to the temporal resolution. Special attention is paid to the behavior of the parameterized subgrid‐scale physics. First, a dynamical core test with reduced dynamics time steps is presented. The results demonstrate that the experimental setup is able to correctly assess the convergence rate of the discrete solutions to the adiabatic equations of atmospheric motion. Second, results from full‐physics CAM5 simulations with reduced physics and dynamics time steps are discussed. It is shown that the convergence rate is 0.4—considerably slower than the expected rate of 1.0. Sensitivity experiments indicate that, among the various subgrid‐scale physical parameterizations, the stratiform cloud schemes are associated with the largest time‐stepping errors, and are the primary cause of slow time step convergence. While the details of our findings are model specific, the general test procedure is applicable to any atmospheric general circulation model. The need for more accurate numerical treatments of physical parameterizations, especially the representation of stratiform clouds, is likely common in many models. The suggested test technique can help quantify the time‐stepping errors and identify the related model sensitivities.

  15. Orientation and heat capacity of horizontally adsorbed molecules in electric fields

    NASA Astrophysics Data System (ADS)

    Liao, Ying-Yen

    2014-02-01

    The orientation and the heat capacity of horizontally adsorbed molecules are investigated in static electric fields. We evaluate the energy spectrum and the wave function to probe the rotational characteristics of the molecule. Numerical results indicate that the electric field and the effect of quantum confinement lead to anticrossing behaviors in the energy levels. The orientation reveals a stepped feature due to the anticrossing in the ground state. Moreover, the heat capacity displays two peaks near the anticrossing. By means of comparison, each peak of the heat capacity corresponds to a particular degree of orientation.

  16. Applications of horizontal well completions to gas-productive formations

    SciTech Connect

    Hill, R.E.; Peterson, R.E.; Middlebrook, M.I. ); Aslakson, J.K. )

    1993-08-01

    The Gas Research Institute (GRI) has initiated a project to determine the reservoir characteristics and appropriate horizontal well designs in various gas-productive formations. The goal of the project is to evaluate horizontal completions as a means of reducing unit production costs in comparison to vertical well-completion methods. Three gas-productive formations were evaluated in the initial phase of the project: the Mancos B on the Douglas Creek arch in northwestern Colorado; the Davis Sand in the Fort Worth basin; and the Barnett Shale, also in the Fort Worth basin. Geologic and engineering data from vertical wells were collected for each formation and used to strategically plan offset horizontal wells. Specifically, information was gathered to characterize the natural and induced fractures, model the reservoirs, and establish a production baseline for each reservoir. The next phase involved GRI participation in the drilling of the three offset horizontal wells with three independent producers. A 1500-ft horizontal section was air drilled across the Mancos B; a 2000-ft horizontal well was air drilled in the Davis sandstone; and a 2000-ft horizontal section was fluid drilled across the 300-ft-thick Barnett Shale. Each of the horizontal wells exhibit varying reservoir characteristics and associated gas production.

  17. Horizontal technology helps spark Louisiana`s Austin chalk trend

    SciTech Connect

    Koen, A.D.

    1996-04-29

    A handful of companies paced by some of the most active operators in the US are pressing the limits of horizontal technology to ramp up Cretaceous Austin chalk exploration and development (E and D) across Louisiana. Companies find applications in Louisiana for lessons learned drilling horizontal wells to produce chalk intervals in Texas in Giddings, Pearsall, and Brookeland fields. Continuing advances in horizontal well technology are helping operators deal with deeper, hotter reservoirs in more complex geological settings that typify the chalk in Louisiana. Better horizontal drilling, completion, formation evaluation, and stimulation techniques have enabled operators to produce oil and gas from formations previously thought to be uneconomical. Most of the improved capabilities stem from better horizontal tools. Horizontal drilling breakthroughs include dual powered mud motors and retrievable whipstocks, key links in the ability to drill wells with more than one horizontal lateral. Better geosteering tools have enabled operators to maintain horizontal wellbores in desired intervals by signaling bit positions downhole while drilling. This paper reviews the technology and provides a historical perspective on the various drilling programs which have been completed in this trend. It also makes predictions on future drilling successes.

  18. Chord Panel Post, Vertical X Bracing & Horizontal Tie Joint ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Chord Panel Post, Vertical X Bracing & Horizontal Tie Joint Detail; Chord Joining Block & Spacer Block Detail; Cross Bracing Joint Detail; Chord Panel Post Diagonal & Horizontal Tie Joint Detail - Jackson Covered Bridge, Spanning Sugar Creek, CR 775N (Changed from Spanning Sugar Creek), Bloomingdale, Parke County, IN

  19. District Power Equalization, Horizontal Equity and the Property Mix.

    ERIC Educational Resources Information Center

    Hilley, John

    1980-01-01

    Argues that the traditional district power equalization (DPE) grant formula achieves horizontal equity, that the formula must be modified when the measure of fiscal capacity differs from the legal tax base, and that the inclusion of a tax exporting variable leads to the breakdown of horizontal equity. (Author/IRT)

  20. Horizontal biases in rats' use of three-dimensional space.

    PubMed

    Jovalekic, Aleksandar; Hayman, Robin; Becares, Natalia; Reid, Harry; Thomas, George; Wilson, Jonathan; Jeffery, Kate

    2011-09-23

    Rodent spatial cognition studies allow links to be made between neural and behavioural phenomena, and much is now known about the encoding and use of horizontal space. However, the real world is three dimensional, providing cognitive challenges that have yet to be explored. Motivated by neural findings suggesting weaker encoding of vertical than horizontal space, we examined whether rats show a similar behavioural anisotropy when distributing their time freely between vertical and horizontal movements. We found that in two- or three-dimensional environments with a vertical dimension, rats showed a prioritization of horizontal over vertical movements in both foraging and detour tasks. In the foraging tasks, the animals executed more horizontal than vertical movements and adopted a "layer strategy" in which food was collected from one horizontal level before moving to the next. In the detour tasks, rats preferred the routes that allowed them to execute the horizontal leg first. We suggest three possible reasons for this behavioural bias. First, as suggested by Grobety and Schenk, it allows minimisation of energy expenditure, inasmuch as costly vertical movements are minimised. Second, it may be a manifestation of the temporal discounting of effort, in which animals value delayed effort as less costly than immediate effort. Finally, it may be that at the neural level rats encode the vertical dimension less precisely, and thus prefer to bias their movements in the more accurately encoded horizontal dimension. We suggest that all three factors are related, and all play a part.

  1. Steerable vertical to horizontal energy transducer for mobile robots

    DOEpatents

    Spletzer, Barry L.; Fischer, Gary J.; Feddema, John T.

    2001-01-01

    The present invention provides a steerable vertical to horizontal energy transducer for mobile robots that less complex and requires less power than two degree of freedom tilt mechanisms. The present invention comprises an end effector that, when mounted with a hopping actuator, translates along axis (typically vertical) actuation into combined vertical and horizontal motion. The end effector, or foot, mounts with an end of the actuator that moves toward the support surface (typically a floor or the earth). The foot is shaped so that the first contact with the support surface is off the axis of the actuator. Off-axis contact with the support surface generates an on-axis force (typically resulting in vertical motion) and a moment orthogonal to the axis. The moment initiates a horizontal tumbling motion, and tilts the actuator so that its axis is oriented with a horizontal component and continued actuation generates both vertical and horizontal force.

  2. Preview Scheduled Model Predictive Control For Horizontal Axis Wind Turbines

    NASA Astrophysics Data System (ADS)

    Laks, Jason H.

    This research investigates the use of model predictive control (MPC) in application to wind turbine operation from start-up to cut-out. The studies conducted are focused on the design of an MPC controller for a 650˜KW, three-bladed horizontal axis turbine that is in operation at the National Renewable Energy Laboratory's National Wind Technology Center outside of Golden, Colorado. This turbine is at the small end of utility scale turbines, but it provides advanced instrumentation and control capabilities, and there is a good probability that the approach developed in simulation for this thesis, will be field tested on the actual turbine. A contribution of this thesis is a method to combine the use of preview measurements with MPC while also providing regulation of turbine speed and cyclic blade loading. A common MPC technique provides integral-like control to achieve offset-free operation. At the same time in wind turbine applications, multiple studies have developed "feed-forward" controls based on applying a gain to an estimate of the wind speed changes obtained from an observer incorporating a disturbance model. These approaches are based on a technique that can be referred to as disturbance accommodating control (DAC). In this thesis, it is shown that offset-free tracking MPC is equivalent to a DAC approach when the disturbance gain is computed to satisfy a regulator equation. Although the MPC literature has recognized that this approach provides "structurally stable" disturbance rejection and tracking, this step is not typically divorced from the MPC computations repeated each sample hit. The DAC formulation is conceptually simpler, and essentially uncouples regulation considerations from MPC related issues. This thesis provides a self contained proof that the DAC formulation (an observer-controller and appropriate disturbance gain) provides structurally stable regulation.

  3. Dairy washwater treatment using a horizontal flow biofilm system.

    PubMed

    Clifford, E; Rodgers, M; Paor, D de

    2008-01-01

    In Ireland, land-spreading is the most widely used method for treating dairy wastewaters. This can be labour intensive and can cause, in some cases, nitrate contamination of groundwater. In this study a simple pilot-scale horizontal flow biofilm reactor (HFBR) with a step-feed was developed and tested at a dairy farm site in County Offaly, Ireland for partial remediation of this soiled water prior to landspreading.During the 122-day study, the top surface plan area (TSPA) hydraulic loading rate was 50 L/m2/day. Influent concentrations averaged: 2904.2 mg total chemical oxygen demand (COD)/L, 950 mg 5-day biochemical oxygen demand (BOD5)/L and 177.9 mg total nitrogen (TN)/L. Between Days 1 and 45 frequent ambient temperatures below 4 degrees C inhibited the build-up of biomass resulting in low removals. From Day 45 the HFBR unit removed 74.9% total COD and 69.6% BOD5, equivalent to TSPA removals of 108.8 g COD/m2/day and 33.1 g BOD5/m2/day. On Sheet 29, by the end of the study, the NH4-N had reduced from 123.1 mg/L in the influent to 37.0 mg/L. TN removal in the reactor averaged 56.0% equating to a TSPA removal rate of 5.0 g TN/m2/day.The HFBR does not require any mechanical aeration, was simple and inexpensive to construct and can provide a robust and economical alternative for the remediation of agricultural soiled water before landspreading.

  4. The stimulus integration area for horizontal vergence.

    PubMed

    Allison, Robert S; Howard, Ian P; Fang, Xueping

    2004-06-01

    Over what region of space are horizontal disparities integrated to form the stimulus for vergence? The vergence system might be expected to respond to disparities within a small area of interest to bring them into the range of precise stereoscopic processing. However, the literature suggests that disparities are integrated over a fairly large parafoveal area. We report the results of six experiments designed to explore the spatial characteristics of the stimulus for vergence. Binocular eye movements were recorded using magnetic search coils. Each dichoptic display consisted of a central target stimulus that the subject attempted to fuse, and a competing stimulus with conflicting disparity. In some conditions the target was stationary, providing a fixation stimulus. In other conditions, the disparity of the target changed to provide a vergence-tracking stimulus. The target and competing stimulus were combined in a variety of conditions including those in which (1) a transparent textured-disc target was superimposed on a competing textured background, (2) a textured-disc target filled the centre of a competing annular background, and (3) a small target was presented within the centre of a competing annular background of various inner diameters. In some conditions the target and competing stimulus were separated in stereoscopic depth. The results are consistent with a disparity integration area with a diameter of about 5 degrees. Stimuli beyond this integration area can drive vergence in their own right, but they do not appear to be summed or averaged with a central stimulus to form a combined disparity signal. A competing stimulus had less effect on vergence when separated from the target by a disparity pedestal. As a result, we propose that it may be more useful to think in terms of an integration volume for vergence rather than a two-dimensional retinal integration area. PMID:14985895

  5. Leading Change Step-by-Step: Tactics, Tools, and Tales

    ERIC Educational Resources Information Center

    Spiro, Jody

    2010-01-01

    "Leading Change Step-by-Step" offers a comprehensive and tactical guide for change leaders. Spiro's approach has been field-tested for more than a decade and proven effective in a wide variety of public sector organizations including K-12 schools, universities, international agencies and non-profits. The book is filled with proven tactics for…

  6. Step by Step to Smoke-Free Schools.

    ERIC Educational Resources Information Center

    VanSciver, James H.; Roberts, H. Earl

    1989-01-01

    This ERIC digest discusses ways of effectively banning smoking in schools so that controversies do not continue after implementation of the policy. By advocating a process approach, the document cites steps taken by the Lake Forest School Board to prohibit smoking in and around school grounds. Step one involved committee planning involving…

  7. Step-By-Step Professional Development in Technology

    ERIC Educational Resources Information Center

    Meltzer, Sarah T.

    2012-01-01

    Don't train your teachers in instructional technology without reading this resource-packed book from Sarah T. Meltzer. Meltzer presents easy-to-follow guidelines for bringing about effective professional development in technology from start to finish. She takes you step-by-step through the process of planning, implementing, and managing…

  8. Guided growth of horizontal nanowires: A new path to self-integrated nanosystems

    NASA Astrophysics Data System (ADS)

    Joselevich, Ernesto

    2014-03-01

    The large-scale assembly of nanowires with controlled orientation on surfaces remains one of the most critical challenges toward their integration into practical devices. We report the vapor-liquid-solid growth of perfectly aligned, millimeter-long, horizontal GaN and ZnO nanowires with controlled crystallographic orientations on different planes of sapphire and other substrates. The growth directions, crystallographic orientation and faceting of the nanowires vary with each surface orientation, as determined by their epitaxial relationship with the substrate, as well as by a graphoepitaxial effect that guides their growth along surface steps and grooves. Despite their interaction with the surface, these horizontally grown nanowires display few structural defects, exhibiting optical and electronic properties comparable to those of vertically grown nanowires. Guided GaN nanowires and ZnO nanowires present general similarities and a few interesting differences, which shed light into the guided growth mechanism. The controlled horizontal growth of nanowires of different materials on different substrates proves the generality of the guided growth approach. Recently, we demonstrated the feasibility of massively parallel ``self-integration'' of NWs into functional systems based on guided growth, including hundreds of sing-NW based field-effect transistors made all at once, and complex logic circuits, such as a 3-bit address decoder. These examples highlight the potential of guided growth for the large-scale integration of nanowires into practical devices.

  9. Nystagmus responses in a group of normal humans during earth-horizontal axis rotation.

    PubMed

    Wall, C; Furman, J M

    1989-01-01

    Horizontal eye movement responses to earth-horizontal yaw axis rotation were evaluated in 50 normal human subjects who were uniformly distributed in age (20-69 years) and equally divided by gender for each decade. The subjects were rotated with eyes open in the dark, using clockwise and counterclockwise 60 degree/s velocity trapezoids. The nystagmus slow component velocity (SCV) was analysed using four parameters: Amp, Bias, Mod and Tau. Amp and Tau characterize the canal-ocular reflex to constant velocity steps, while Mod and Bias characterize the "AC" and "DC" components of the otolith-ocular reflex. Results indicated that intersubject variability was larger than that seen in earth-vertical axis data. Tau depended significantly (p less than 0.05) upon subject gender, while Mod increased monotonically with age decade. Linear regression showed a positive correlation between pairs of SCV magnitude parameters (Amp, Bias and Mod), suggesting a common scaling effect. In addition, there was a negative correlation between the value of the decay time constant Tau and each of the three magnitude parameters. Thus, despite large intersubject variability, parameters that describe earth-horizontal yaw axis responses are loosely interrelated and some of them vary significantly with gender and age.

  10. Effect of Passive Horizontal Rotations and Vertical Oscillations on Dynamic Visual Acuity

    NASA Technical Reports Server (NTRS)

    Mulavara, Ajitkumar; Peters, Brian; Wood, Scott; Cohen, Helen; Kulecz, Walter B.; Miller, Chris; Reschke, Millard; Bloomberg, Jacob

    2010-01-01

    Astronauts experience sensorimotor disturbances after long duration space flight. These crewmembers may need to egress the vehicle within a few minutes for safety and operational reasons in various sea state conditions following a water landing. Exposure to even low frequency motions induced by sea conditions surrounding a vessel can cause significant fine and gross motor control problems affecting critical functions. The objective of this study was to document human motor and visual performance during simulated wave motion in the 0.1 to 2.0 Hz range. We examined in 12 healthy subjects the changes in accuracy when performing a seated visual target acquisition task in which the location of target was offset vertically during horizontal full body rotation at an oscillating frequency of 0.8 Hz (peak velocity of 160 deg/s). The main finding was that the accuracy of performance degraded in 7 of 12 subjects when acquiring vertical targets at perturbing frequencies of 0.8 Hz in the horizontal plane by one step size. We also examined in a separate study on 12 healthy subjects seated dynamic visual acuity (DVA) task performance during vertical full body oscillations at perturbing frequencies of 2 Hz (peak to peak motion of 5 cm). The main finding was that DVA was significantly reduced when acquiring targets at perturbing oscillations at frequencies of 2 Hz in the vertical plane by approximately 1 chart line. Thus low frequencies of perturbations in the horizontal and vertical planes can cause decrement in visual performance.

  11. Horizontal oil well applications and oil recovery assessment. Volume 1: Success of horizontal well technology, Final report

    SciTech Connect

    Deskins, W.G.; McDonald, W.J.; Knoll, R.G.; Springer, S.J.

    1995-03-01

    Horizontal technology has been applied in over 110 formations in the USA. Volume I of this study addresses the overall success of horizontal technology, especially in less-publicized formations, i.e., other than the Austin Chalk, Bakken, and Niobrara. Operators in the USA. and Canada were surveyed on a formation-by-formation basis by means of a questionnaire. Response data were received describing horizontal well projects in 58 formations in the USA. and 88 in Canada. Operators responses were analyzed for trends in technical and economic success based on lithology (clastics and carbonates) and resource type (light oil, heavy oil, and gas). The potential impact of horizontal technology on reserves was also estimated. A forecast of horizontal drilling activity over the next decade was developed.

  12. Physical modeling of stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped spillways applied to embankment dams are becoming popular for addressing the rehabilitation of aging watershed dams, especially those situated in the urban landscape. Stepped spillways are typically placed over the existing embankment, which provides for minimal disturbance to the original ...

  13. Development of a "Steps Questionnaire".

    PubMed

    Gilbert, F S

    1991-07-01

    Thousands of men and women have begun their recovery from alcoholism through the support of Alcoholics Anonymous (AA) and its well-known "12-Step" program. The purpose of the present study was to develop a scale to measure alcoholics' levels of agreement with the first three of AA's 12 Steps and to test the relationship between sobriety and belief in these three steps. Using both factor analysis and Rasch analysis, two versions of a "Steps Questionnaire" were developed. A 96-member subset of the original subject pool was assessed quarterly for 1 year following inpatient treatment to determine the predictive validity of the questionnaire. The results of this study suggested that agreement with AA's first three steps can be measured and that agreement with AA's first step correlates with number of sober days posttreatment. The dichotomization of Steps Questionnaire scores into total agreement versus partial agreement with Step 1, and from this the reduction of uncertainty in the prediction of abstention over a lengthy follow-up period, provides support for AA's contention that total surrender to one's powerlessness over alcohol is part of the process of achieving abstention.

  14. Formation damage effects on horizontal-well flow efficiency

    SciTech Connect

    Renard, G.; Dupuy, J.M. )

    1991-07-01

    Wellbore damage commonly is accounted for by an apparent skin factor. A better relative index for determining the efficiency with which a well has been drilled and completed is the flow efficiency, the ration of a well's actual PI to ideal PI. The flow efficiency of horizontal wells is derived assuming steady-state flow of an incompressible fluid in a homogeneous, anisotropic medium. A comparison between the flow efficiencies of vertical and horizontal wells indicates that permeability reduction around the wellbore is less detrimental to horizontal wells. This paper shows that the effect of damage around a horizontal wellbore is reduced slightly by increasing the well length. Conversely, if the vertical permeability is less than the horizontal permeability, the anisotropy ratio, {radical} k{sub H}/k{sub V}, magnifies the influence of formation damage near the horizontal wellbore. Examples of flow efficiency calculations assuming a formation damage or a formation collapse around a liner in poorly consolidated formations are provided for horizontal and vertical wells.

  15. Geologic aspects of horizontal drilling in self-sourcing reservoirs

    SciTech Connect

    Illich, H.A. )

    1991-03-01

    Horizontal drilling techniques provide a way to exploit hydrocarbon reserves that are either noneconomic or only marginally economic using vertical drilling techniques. A significant fraction of these reserves is contained in reservoirs that are self-sourcing or in reservoirs that are closely associated with their resources. Most formations drilled as horizontal targets are self-sourcing. The Austin Chalk, Niobrara, Mesaverde, and Bakken are examples of horizontally drilled, self-sourcing reservoir systems. In formations like the Bakken or Austin Chalk, the close relationship between reservoir and source makes risks associated with migration and accumulation less important. Reservoirs of this kind can contain oil or gas and often have little or no associated water. They can be matrix-dominated reservoirs, dual-porosity reservoirs (Mesaverde), or fractured reservoirs (Austin Chalk, Bakken, and Niobrara). Fractured, self-sourcing reservoirs also can possess matrix characteristics that contribute increased recovery efficiency. Most reservoirs drilled horizontally possess matrix characteristics that contribute increased recovery efficiency. Most reservoirs drilled horizontally possess highly heterogeneous reservoir systems. Characterization of the style of reservoir heterogeneity in self-sourcing systems is important if the favorable properties of horizontally oriented bore holes are to be realized. Production data and rock mechanics considerations are important in horizontal drilling ventures. Examples of the use of these data for the purpose of defining reservoir characteristics are discussed. Knowledge of lateral changes in reservoir properties is essential if we are to recover known reserves efficiently.

  16. Chromospheric Circulation Driven by Horizontally Inhomogeneous Heating

    NASA Astrophysics Data System (ADS)

    Vasyliunas, V. M.; Song, P.

    2013-12-01

    The rate of chromospheric heating by damping of Alfvén waves propagating upward from below the photosphere (Song and Vasyliunas, 2011) depends on the strength of the magnetic field. In regions of locally confined very strong magnetic field, particularly at the boundaries of the chromospheric network, the heating rate is greatly enhanced, and the heating per unit mass is concentrated toward higher altitudes. Song and Vasyliunas (2012) proposed that the resulting inhomogeneity of pressure may drive circulating flows in the chromosphere, horizontally away from the strong-field region at one altitude and returning at another. We investigate this circulation further, with particular attention to the flow patterns and to the question to what extent the circulation might be impeded by MHD effects. The heating process acts equally on the plasma and on the neutral gas, but because most of the chromosphere is weakly ionized, the flow is predominantly that of the neutral gas. Below the altitude he at which electron collision frequency equals electron gyrofrequency, all the species (electrons, ions, neutrals) flow together; the magnetic field can change relative to the flow only by diffusion. In the altitude range above he but below the altitude hi at which ion collision frequency equals ion gyrofrequency, ions and neutrals flow together, but electron flow is decoupled from neutral flow; the magnetic field is frozen to the motion of electrons. Above hi neutrals are decoupled from ions, while electrons and ions flow nearly together with the common plasma flow; the magnetic field is frozen to the plasma flow. (This is analogous to the well-studied neutral-wind dynamo process in the terrestrial ionosphere and thermosphere, except that at the Sun there is no counterpart to the non-conducting terrestrial atmosphere.) The circulation, confined to altitudes above he, consists of neutral and ion flow between he and hi; above hi, there is only neutral flow, with ions at rest, while

  17. Photometric identification of blue horizontal branch stars

    NASA Astrophysics Data System (ADS)

    Smith, K. W.; Bailer-Jones, C. A. L.; Klement, R. J.; Xue, X. X.

    2010-11-01

    We investigate the performance of some common machine learning techniques in identifying blue horizontal branch (BHB) stars from photometric data. To train the machine learning algorithms, we use previously published spectroscopic identifications of BHB stars from Sloan digital sky survey (SDSS) data. We investigate the performance of three different techniques, namely k nearest neighbour classification, kernel density estimation for discriminant analysis and a support vector machine (SVM). We discuss the performance of the methods in terms of both completeness (what fraction of input BHB stars are successfully returned as BHB stars) and contamination (what fraction of contaminating sources end up in the output BHB sample). We discuss the prospect of trading off these values, achieving lower contamination at the expense of lower completeness, by adjusting probability thresholds for the classification. We also discuss the role of prior probabilities in the classification performance, and we assess via simulations the reliability of the dataset used for training. Overall it seems that no-prior gives the best completeness, but adopting a prior lowers the contamination. We find that the support vector machine generally delivers the lowest contamination for a given level of completeness, and so is our method of choice. Finally, we classify a large sample of SDSS Data Release 7 (DR7) photometry using the SVM trained on the spectroscopic sample. We identify 27 074 probable BHB stars out of a sample of 294 652 stars. We derive photometric parallaxes and demonstrate that our results are reasonable by comparing to known distances for a selection of globular clusters. We attach our classifications, including probabilities, as an electronic table, so that they can be used either directly as a BHB star catalogue, or as priors to a spectroscopic or other classification method. We also provide our final models so that they can be directly applied to new data. Full Tables 7, A.3

  18. Computational studies of horizontal axis wind turbines

    NASA Astrophysics Data System (ADS)

    Xu, Guanpeng

    A numerical technique has been developed for efficiently simulating fully three-dimensional viscous fluid flow around horizontal axis wind turbines (HAWT) using a zonal approach. The flow field is viewed as a combination of viscous regions, inviscid regions and vortices. The method solves the costly unsteady Reynolds averaged Navier-Stokes (RANS) equations only in the viscous region around the turbine blades. It solves the full potential equation in the inviscid region where flow is irrotational and isentropic. The tip vortices are simulated using a Lagrangean approach, thus removing the need to accurately resolve them on a fine grid. The hybrid method is shown to provide good results with modest CPU resources. A full Navier-Stokes based methodology has also been developed for modeling wind turbines at high wind conditions where extensive stall may occur. An overset grid based version that can model rotor-tower interactions has been developed. Finally, a blade element theory based methodology has been developed for the purpose of developing improved tip loss models and stall delay models. The effects of turbulence are simulated using a zero equation eddy viscosity model, or a one equation Spalart-Allmaras model. Two transition models, one based on the Eppler's criterion, and the other based on Michel's criterion, have been developed and tested. The hybrid method has been extensively validated for axial wind conditions for three rotors---NREL Phase II, Phase III, and Phase VI configurations. A limited set of calculations has been done for rotors operating under yaw conditions. Preliminary simulations have also been carried out to assess the effects of the tower wake on the rotor. In most of these cases, satisfactory agreement has been obtained with measurements. Using the numerical results from present methodologies as a guide, Prandtl's tip loss model and Corrigan's stall delay model were correlated with present calculations. An improved tip loss model has been

  19. Tank Tests of Models of Flying Boat Hulls Having Longitudinal Steps

    NASA Technical Reports Server (NTRS)

    Allison, John M; Ward, Kenneth E

    1936-01-01

    Four models with longitudinal steps on the forebody were developed by modification of a model of a conventional hull and were tested in the National Advisory Committee for Aeronautics (NACA) tank. Models with longitudinal steps were found to have smaller resistance at high speed and greater resistance at low speed than the parent model that had the same afterbody but a conventional V-section forebody. The models with a single longitudinal step had better performance at hump speed and as low high-speed resistance except at very light loads. Spray strips at angles from 0 degrees to 45 degrees to the horizontal were fitted at the longitudinal steps and at the chine on one of the two step models having two longitudinal steps. The resistance and the height of the spray were less with each of the spray strips than without; the most favorable angle was found to lie between 15 degrees and 30 degrees.

  20. Progress in Horizontal and Slant-Path Imaging Speckle Imaging

    SciTech Connect

    Carrano, C J

    2003-01-30

    The difficulty in terrestrial imaging over long horizontal or slant paths is that atmospheric aberrations and distortions reduce the resolution and contrast in images recorded at high resolution. This paper will describe the problem of horizontal-path imaging, briefly cover various methods for imaging over horizontal paths and then describe the speckle imaging method actively being pursued at LLNL. We will review some closer range (1-3 km range) imagery of people we have already published, as well as show new results of vehicles we have obtained over longer slant-range paths greater than 20 km.

  1. Horizontal Transfer and the Evolution of Host-Pathogen Interactions

    PubMed Central

    de la Casa-Esperón, Elena

    2012-01-01

    Horizontal gene transfer has been long known in viruses and prokaryotes, but its importance in eukaryotes has been only acknowledged recently. Close contact between organisms, as it occurs between pathogens and their hosts, facilitates the occurrence of DNA transfer events. Once inserted in a foreign genome, DNA sequences have sometimes been coopted by pathogens to improve their survival or infectivity, or by hosts to protect themselves against the harm of pathogens. Hence, horizontal transfer constitutes a source of novel sequences that can be adopted to change the host-pathogen interactions. Therefore, horizontal transfer can have an important impact on the coevolution of pathogens and their hosts. PMID:23227424

  2. Step-by-step growth of complex oxide microstructures

    SciTech Connect

    Datskos, Panos G.; Cullen, David A.; Sharma, Jaswinder K.

    2015-06-10

    The synthesis of complex and hybrid oxide microstructures is of fundamental interest and practical applications. However, the design and synthesis of such structures is a challenging task. We developed a solution phase process to synthesize complex silica and silica titania hybrid microstructures by exploiting the emulsion droplet based shape control and step by step growth. The strategy is robust and can be extended to make complex hybrid structures made of two or more materials while each having its own shape.

  3. Two-step electroweak baryogenesis

    NASA Astrophysics Data System (ADS)

    Inoue, Satoru; Ovanesyan, Grigory; Ramsey-Musolf, Michael J.

    2016-01-01

    We analyze electroweak baryogenesis during a two-step electroweak symmetry-breaking transition, wherein the baryon asymmetry is generated during the first step and preserved during the second. Focusing on the dynamics of C P violation required for asymmetry generation, we discuss general considerations for successful two-step baryogenesis. Using a concrete model realization, we illustrate in detail the viability of this scenario and the implications for present and future electric dipole moment (EDM) searches. We find that C P violation associated with a partially excluded sector may yield the observed baryon asymmetry while evading present and future EDM constraints.

  4. 27. Credit JTL. Second floor, detail of Eureka horizontal wheat ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. Credit JTL. Second floor, detail of Eureka horizontal wheat scourer, by S. Howes Co., (Silver Creek, NY). After leaving scourer, grain passed directly to the Midget Marvel Machine. - Bunker Hill Mill, County Route 26, Bunker Hill, Berkeley County, WV

  5. Chord, Horizontal Tie Bar & Crossbracing Joint Details; Crossbracing Center ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Chord, Horizontal Tie Bar & Crossbracing Joint Details; Crossbracing Center Joint Detail; Chord, Panel Posts, Braces & Counterbrace Joint Detail - Brownsville Covered Bridge, Spanning East Fork Whitewater River (moved to Eagle Creek Park, Indianapolis), Brownsville, Union County, IN

  6. Lessons learned from installation of an environmental horizontal well

    SciTech Connect

    Oakley, D.B.; Nickelson, M.D.

    1994-12-31

    At Williams Air Force Base near Phoenix, Arizona, a Pilot Study/Demonstration Study is being performed to evaluate the effectiveness of horizontal vs vertical wells in remediating and containing a jet fuel contaminant plume. An early stage of this project included successful installation of the world`s longest, deepest environmental horizontal wells. The horizontal well was installed using river crossing technology developed for drilling boreholes and installing utility conduits under rivers. Boreholes over 5,000 ft long have been successfully installed using river crossing technology. However, these boreholes are typically shallower than 100 ft below land surface (BLS). Installation of the environmental horizontal well proved to be extremely challenging because of the depth (235 ft BLS), the length (2,500 ft) of the borehole, and the requirements dictated by well installation criteria. Two installation attempts failed before the successful installation.

  7. Naval Air Station Lighter than Air Hangar, wood construction horizontal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Naval Air Station Lighter than Air Hangar, wood construction horizontal rolling door. Drawing no. 2122 820. - Marine Corps Air Station Tustin, Northern Lighter Than Air Ship Hangar, Meffett Avenue & Maxfield Street, Tustin, Orange County, CA

  8. Naval Air Station Lighter than Air Hangar, wood construction horizontal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Naval Air Station Lighter than Air Hangar, wood construction horizontal rolling door. Drawing no. 2122 820. - Marine Corps Air Station Tustin, East of Red Hill Avenue between Edinger Avenue & Barranca Parkway, Tustin, Orange County, CA

  9. Horizontal running mattress suture modified with intermittent simple loops.

    PubMed

    Chacon, Anna H; Shiman, Michael I; Strozier, Narissa; Zaiac, Martin N

    2013-01-01

    Using the combination of a horizontal running mattress suture with intermittent loops achieves both good eversion with the horizontal running mattress plus the ease of removal of the simple loops. This combination technique also avoids the characteristic railroad track marks that result from prolonged non-absorbable suture retention. The unique feature of our technique is the incorporation of one simple running suture after every two runs of the horizontal running mattress suture. To demonstrate its utility, we used the suturing technique on several patients and analyzed the cosmetic outcome with post-operative photographs in comparison to other suturing techniques. In summary, the combination of running horizontal mattress suture with simple intermittent loops demonstrates functional and cosmetic benefits that can be readily taught, comprehended, and employed, leading to desirable aesthetic results and wound edge eversion.

  10. 7. NORTH SIDE CHESTNUT ST. (horizontal line) BETWEEN THIRD (left) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. NORTH SIDE CHESTNUT ST. (horizontal line) BETWEEN THIRD (left) AND BREAD (right) STS., SHOWING OLD BUILDINGS - Independence National Historical Park, Walnut, Sixth, Chestnut & Second Streets, Philadelphia, Philadelphia County, PA

  11. 16. INDEPENDENCE HALL LOOKING SOUTH ON CHESTNUT ST. (horizontal line) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. INDEPENDENCE HALL LOOKING SOUTH ON CHESTNUT ST. (horizontal line) BETWEEN SIXTH (right) AND FIFTH (left) STS. - Independence National Historical Park, Walnut, Sixth, Chestnut & Second Streets, Philadelphia, Philadelphia County, PA

  12. 2. EAST ELEVATION OF POWER PLANT TEST STAND (HORIZONTAL TEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. EAST ELEVATION OF POWER PLANT TEST STAND (HORIZONTAL TEST STAND REMNANTS OF BUILDING-BLANK WHITE WALL ONLY ORIGINAL REMAINS. - Marshall Space Flight Center, East Test Area, Power Plant Test Stand, Huntsville, Madison County, AL

  13. 10. INTERIOR VIEW OF BUILDING 106, SHOWING HORIZONTAL CATAPULT, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. INTERIOR VIEW OF BUILDING 106, SHOWING HORIZONTAL CATAPULT, LOOKING NORTHEAST - Frankford Arsenal, Building No. 106, South of Tacony Street between Bridge Street & tracks of former Pennsylvania Railroad, Philadelphia, Philadelphia County, PA

  14. 9. INTERIOR VIEW OF BUILDING 106, SHOWING HORIZONTAL CATAPULT, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. INTERIOR VIEW OF BUILDING 106, SHOWING HORIZONTAL CATAPULT, LOOKING NORTHEAST - Frankford Arsenal, Building No. 106, South of Tacony Street between Bridge Street & tracks of former Pennsylvania Railroad, Philadelphia, Philadelphia County, PA

  15. 7. Underside of Roadbed (Interior beams cast horizontal, imprints of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Underside of Roadbed (Interior beams cast horizontal, imprints of timbers used as formwork visible on abutment walls and beams) - North Bridge, Spanning Quarton Lake branch of River Rouge, Birmingham, Oakland County, MI

  16. 7. Underside of Roadbed (Interior beams cast horizontal, imprints of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Underside of Roadbed (Interior beams cast horizontal, imprints of timbers used as formwork visible on abutment walls and beams) - South Bridge, Spanning Quarton Lake branch of River Rouge, Birmingham, Oakland County, MI

  17. 15. Detail of Well Head Showing Horizontal Release Pipe for ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Detail of Well Head Showing Horizontal Release Pipe for Natural Gas, Looking North - David Renfrew Oil Rig, East side of Connoquenessing Creek, 0.4 mile North of confluence with Thorn Creek, Renfrew, Butler County, PA

  18. 5. HORIZONTAL COOLEDWATER STORAGE TANKS. Hot Springs National Park, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. HORIZONTAL COOLED-WATER STORAGE TANKS. - Hot Springs National Park, Bathhouse Row, Fordyce Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  19. Determination of Elastic Twist in Horizontal Axis Wind Turbines (HAWTs)

    SciTech Connect

    Stoddard, F.; Nelson, V.; Starcher, K.; Andrews, B.

    2006-06-01

    This report presents the results of a project at the Alternative Energy Institute (AEI) which measured and calculated the elastic twist of three representative composite horizontal-axis blades: Carter 300, Gougeon ESI 54, and UTRC 8 kW.

  20. 36. ISLAND PLANT: Nos. 1 AND 2 TWENTYSIX INCH HORIZONTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. ISLAND PLANT: Nos. 1 AND 2 TWENTY-SIX INCH HORIZONTAL SAMSON TURBINES - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  1. 13. DETAIL OF BEVEL GEAR TRANSFERRING HORIZONTAL DRIVE FROM MAIN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. DETAIL OF BEVEL GEAR TRANSFERRING HORIZONTAL DRIVE FROM MAIN WATERWHEEL SHAFT TO VERTICAL SHAFT DRIVING COFFEE HUSKING MILL ON SECOND FLOOR - Hacienda Cafetalera Santa Clara, Coffee Mill, KM 19, PR Route 372, Hacienda La Juanita, Yauco Municipio, PR

  2. Robust syntaxin-4 immunoreactivity in mammalian horizontal cell processes

    PubMed Central

    HIRANO, ARLENE A.; BRANDSTÄTTER, JOHANN HELMUT; VILA, ALEJANDRO; BRECHA, NICHOLAS C.

    2009-01-01

    Horizontal cells mediate inhibitory feed-forward and feedback communication in the outer retina; however, mechanisms that underlie transmitter release from mammalian horizontal cells are poorly understood. Toward determining whether the molecular machinery for exocytosis is present in horizontal cells, we investigated the localization of syntaxin-4, a SNARE protein involved in targeting vesicles to the plasma membrane, in mouse, rat, and rabbit retinae using immunocytochemistry. We report robust expression of syntaxin-4 in the outer plexiform layer of all three species. Syntaxin-4 occurred in processes and tips of horizontal cells, with regularly spaced, thicker sandwich-like structures along the processes. Double labeling with syntaxin-4 and calbindin antibodies, a horizontal cell marker, demonstrated syntaxin-4 localization to horizontal cell processes; whereas, double labeling with PKC antibodies, a rod bipolar cell (RBC) marker, showed a lack of co-localization, with syntaxin-4 immunolabeling occurring just distal to RBC dendritic tips. Syntaxin-4 immunolabeling occurred within VGLUT-1-immunoreactive photoreceptor terminals and underneath synaptic ribbons, labeled by CtBP2/RIBEYE antibodies, consistent with localization in invaginating horizontal cell tips at photoreceptor triad synapses. Vertical sections of retina immunostained for syntaxin-4 and peanut agglutinin (PNA) established that the prominent patches of syntaxin-4 immunoreactivity were adjacent to the base of cone pedicles. Horizontal sections through the OPL indicate a one-to-one co-localization of syntaxin-4 densities at likely all cone pedicles, with syntaxin-4 immunoreactivity interdigitating with PNA labeling. Pre-embedding immuno-electron microscopy confirmed the subcellular localization of syntaxin-4 labeling to lateral elements at both rod and cone triad synapses. Finally, co-localization with SNAP-25, a possible binding partner of syntaxin-4, indicated co-expression of these SNARE proteins in

  3. SNAP25 Expression in Mammalian Retinal Horizontal Cells

    PubMed Central

    Hirano, Arlene A.; Brandstätter, Johann Helmut; Morgans, Catherine W.; Brecha, Nicholas C.

    2014-01-01

    Horizontal cells mediate inhibitory feedforward and feedback lateral interactions in the outer retina at photoreceptor terminals and bipolar cell dendrites; however, the mechanisms that underlie synaptic transmission from mammalian horizontal cells are poorly understood. The localization of a vesicular γ-aminobutyric acid (GABA) transporter (VGAT) to horizontal cell processes in primate and rodent retinae suggested that mammalian horizontal cells release transmitter in a vesicular manner. Toward determining whether the molecular machinery for vesicular transmitter release is present in horizontal cells, we investigated the expression of SNAP25 (synaptosomal-associated protein of 25 kDa), a key SNARE protein, by immunocytochemistry with cell type-specific markers in the retinae of mouse, rat, rabbit, and monkey. Different commercial antibodies to SNAP25 were tested on vertical sections of retina. We report the robust expression of SNAP25 in both plexiform layers. Double labeling with SNAP25 and calbindin antibodies demonstrated that horizontal cell processes and their endings in photoreceptor triad synapses were strongly labeled for both proteins in mouse, rat, rabbit, and monkey retinae. Double labeling with parvalbumin antibodies in monkey retina verified SNAP25 immunoreactivity in all horizontal cells. Pre-embedding immunoelectron microscopy in rabbit retina confirmed expression of SNAP25 in lateral elements within photoreceptor triad synapses. The SNAP25 immunoreactivity in the plexiform layers and outer nuclear layer fell into at least three patterns depending on the antibody, suggesting a differential distribution of SNAP25 isoforms. The presence of SNAP25a and SNAP25b isoforms in mouse retina was established by reverse transcriptase-polymerase chain reaction. SNAP25 expression in mammalian horizontal cells along with other SNARE proteins is consistent with vesicular exocytosis. PMID:21280047

  4. SATURATED-SUBCOOLED STRATIFIED FLOW IN HORIZONTAL PIPES

    SciTech Connect

    Richard Schultz

    2010-08-01

    Advanced light water reactor systems are designed to use passive emergency core cooling systems with horizontal pipes that provide highly subcooled water from water storage tanks or passive heat exchangers to the reactor vessel core under accident conditions. Because passive systems are driven by density gradients, the horizontal pipes often do not flow full and thus have a free surface that is exposed to saturated steam and stratified flow is present.

  5. You have no credibility: nursing students' experiences of horizontal violence.

    PubMed

    Curtis, Janette; Bowen, Isla; Reid, Amanda

    2007-05-01

    Horizontal violence is a significant issue confronting the nursing profession both in Australia and internationally. The term horizontal violence is used to describe bullying and aggression involving inter-group conflict. Some evidence suggests that nursing students commonly experience this during clinical placement(s). Despite the current shortage of nurses and the fact that clinical placement experiences may influence whether students remain in the nursing profession, there has been little research undertaken on this topic. This study used a questionnaire to investigate 152 second and third year nursing student's experiences of horizontal violence (either directly experienced or witnessed). Analysis identified five major themes: humiliation and lack of respect; powerlessness and becoming invisible; hierarchical nature of horizontal violence; coping strategies; and future employment choices. More than half of the sample indicated that they had experienced or witnessed horizontal violence; importantly, most of these (51% of the total sample) also indicated that it would impact on their future career and/or their employment choices. Strategies are discussed that could be implemented to reduce the effect of horizontal violence, including giving a higher priority to debriefing within a supportive university environment, and teaching assertiveness and conflict resolution skills within the Bachelor of Nursing Degree. PMID:17689439

  6. Horizontal Launch: A Versatile Concept for Assured Space Access

    NASA Technical Reports Server (NTRS)

    Bartolotta, Paul; Wilhite, Alan W.; Schaffer, Mark; Voland, Randall T.; Huebner, Larry

    2011-01-01

    The vision of horizontal launch is the capability to provide a mobile launch pad that can use existing aircraft runways, cruise above weather, loiter for mission instructions, and achieve precise placement for orbital intercept, rendezvous, or reconnaissance. Another compelling benefit of horizontal launch is that today s ground-based vertical launch pads are a single earthquake, hurricane, or terrorist attack away from disruption of critical U.S. launch capabilities. The study did not attempt to design a new system concept for horizontal launch, but rather focused on the refinement of many previously-studied horizontal launch concepts. Because of the large number of past horizontal launch studies, a process was developed to narrow the number of concepts through prescreening, screening, and evaluation of point designs. The refinement process was not intended to select the "best" concept, but rather to establish the feasibility of horizontal launch from a balanced assessment of figures of merit and to identify potential concepts that warrant further exploration.

  7. Utilization of horizontal drainholes in developing multilayered reservoir

    SciTech Connect

    Siddiqui, T.K.; Al Khatib, H.M.; Sultan, A.J.

    1995-10-01

    Drilling deviated wells in the Upper Zakum field did not allow to develop this field to its full potential. It is an offshore field, only a limited number of platforms are available. Therefore, it may become uneconomical to drill a large number of deviated wells for the full development of the reservoirs. Application of horizontal wells in this filed helped in redeveloping the reservoirs. Data were integrated form different petroleum engineering disciplines and analyzed to identify problems in the reservoirs. Horizontal wells played a vital role to resolve various problems faced in different parts of these heterogeneous reservoirs. This paper reviews the field development strategy which was further refined with time as more horizontal wells were drilled in this field. Performance of horizontal wells have been compared and evaluated with the deviated wells. A brief discussion on drilling, completion, and stimulation procedures used for horizontal wells has also been included. This study contributed to some extent in resolving reservoir problems ranging from enhancement of productivity index, development of reservoir flanks, and recovering un-swept oil from water flooded layers with the applications of horizontal wells.

  8. Should sex-ratio distorting parasites abandon horizontal transmission?

    PubMed Central

    2011-01-01

    Background Sex-ratio distorting parasites are of interest due to their effects upon host population dynamics and their potential to influence the evolution of host sex determination systems. In theory, the ability to distort host sex-ratios allows a parasite with efficient vertical (hereditary) transmission to dispense completely with horizontal (infectious) transmission. However, recent empirical studies indicate that some sex-ratio distorting parasites have retained the capability for horizontal transmission. Results Numerical simulations using biologically realistic parameters suggest that a feminising parasite is only likely to lose the capability for horizontal transmission if its host occurs at low density and/or has a male-biased primary sex ratio. It is also demonstrated that even a small amount of horizontal transmission can allow multiple feminising parasites to coexist within a single host population. Finally it is shown that, by boosting its host's rate of population growth, a feminising parasite can increase its own horizontal transmission and allow the invasion of other, more virulent parasites. Conclusions The prediction that sex-ratio distorting parasites are likely to retain a degree of horizontal transmission has important implications for the epidemiology and host-parasite interactions of these organisms. It may also explain the frequent co-occurrence of several sex-ratio distorting parasite species in nature. PMID:22188680

  9. Transoral Robotic Surgery: Step-by-Step Radical Tonsillectomy

    PubMed Central

    Millas, Teresa

    2014-01-01

    Introduction. Transoral robotic surgery (TORS) radical tonsillectomy is an emerging minimally invasive surgical procedure for the treatment of cancer of the tonsil. The detailed surgical technique and claims for its reproducibility have been previously published. Case Presentation. We present a patient with a T2N2bM0 epidermoid carcinoma of the tonsil to illustrate step by step the surgical procedure for TORS radical tonsillectomy. Neck dissection and TORS were staged. No surgical reconstruction of the defect was required. No tracheostomy was necessary. The patient could eat without any feeding tube and was on full oral diet on the fifth postoperative day. Discussion. The transoral approach offers the benefits of minimally invasive surgery to patients with cancer of the tonsil. The excellent exposure and high precision provided by robotic instrumentation allow the surgeon to closely follow and accomplish the surgical steps, which is the best warranty for safety and effectiveness. PMID:24808963

  10. A step-by-step methodology for enterprise interoperability projects

    NASA Astrophysics Data System (ADS)

    Chalmeta, Ricardo; Pazos, Verónica

    2015-05-01

    Enterprise interoperability is one of the key factors for enhancing enterprise competitiveness. Achieving enterprise interoperability is an extremely complex process which involves different technological, human and organisational elements. In this paper we present a framework to help enterprise interoperability. The framework has been developed taking into account the three domains of interoperability: Enterprise Modelling, Architecture and Platform and Ontologies. The main novelty of the framework in comparison to existing ones is that it includes a step-by-step methodology that explains how to carry out an enterprise interoperability project taking into account different interoperability views, like business, process, human resources, technology, knowledge and semantics.

  11. Step-by-Step Growth of Complex Oxide Microstructures.

    PubMed

    Datskos, Panos; Cullen, David A; Sharma, Jaswinder

    2015-07-27

    The synthesis of complex and hybrid oxide microstructures is of fundamental interest and practical applications. However, the design and synthesis of such structures is a challenging task. A solution-phase process to synthesize complex silica and silica-titania hybrid microstructures was developed by exploiting the emulsion-droplet-based step-by-step growth featuring shape control. The strategy is robust and can be extended to the preparation of complex hybrid structures consisting of two or more materials, with each having its own shape. PMID:26095228

  12. Writing a Simulation Scenario: A Step-By-Step Guide.

    PubMed

    Bambini, Deborah

    2016-02-01

    Simulation is becoming a widely used method of helping nurses learn and maintain competency in the clinical area for both staff educators in clinical settings and nursing faculty in academic settings. Designing an effective simulation experience requires thoughtful planning, knowledge of educational principles, and knowledge of best practices in both simulation and clinical practice. An evidence-based strategy for writing a simulation scenario for nurses and other health care providers in any setting is described. A step-by-step process is outlined that incorporates best practices. Examples and suggestions are provided to help readers create quality simulation experiences.

  13. Partial return yoke for MICE step IV and final step

    SciTech Connect

    Witte, H.; Plate, S.; Berg, J. S.; Tarrant, J.; Bross, A.

    2015-05-03

    This paper reports on the progress of the design and construction of a retro-fitted return yoke for the international Muon Ionization Cooling Experiment (MICE). MICE is a proof-of-principle experiment aiming to demonstrate ionization cooling experimentally. In earlier studies we outlined how a partial return yoke can be used to mitigate stray magnetic field in the experimental hall; we report on the progress of the construction of the partial return yoke for MICE Step IV. We also discuss an extension of the Partial Return Yoke for the final step of MICE; we show simulation results of the expected performance.

  14. Partial Return Yoke for MICE Step IV and Final Step

    SciTech Connect

    Witte, Holger; Plate, Stephen; Berg, J.Scott; Tarrant, Jason; Bross, Alan

    2015-06-01

    This paper reports on the progress of the design and construction of a retro-fitted return yoke for the international Muon Ionization Cooling Experiment (MICE). MICE is a proof-of-principle experiment aiming to demonstrate ionization cooling experimentally. In earlier studies we outlined how a partial return yoke can be used to mitigate stray magnetic field in the experimental hall; we report on the progress of the construction of the partial return yoke for MICE Step IV. We also discuss an extension of the Partial Return Yoke for the final step of MICE; we show simulation results of the expected performance.

  15. An isoform of retinoid-related orphan receptor β directs differentiation of retinal amacrine and horizontal interneurons

    PubMed Central

    Liu, Hong; Kim, Soo-Young; Fu, Yulong; Wu, Xuefeng; Ng, Lily; Swaroop, Anand; Forrest, Douglas

    2013-01-01

    Amacrine and horizontal interneurons integrate visual information as it is relayed through the retina from the photoreceptors to the ganglion cells. The early steps that generate these interneuron networks remain unclear. Here we show that a distinct RORβ1 isoform encoded by the retinoid-related orphan nuclear receptor β gene (Rorb) is critical for both amacrine and horizontal cell differentiation in mice. A fluorescent protein cassette targeted into Rorb revealed RORβ1 as a novel marker of immature amacrine and horizontal cells and of undifferentiated, dividing progenitor cells. RORβ1-deficient mice lose expression of pancreas-specific transcription factor 1a (Ptf1a) but retain forkhead box n4 factor (Foxn4), two early-acting factors necessary for amacrine and horizontal cell generation. RORβ1 and Foxn4 synergistically induce Ptf1a expression, suggesting a central role for RORβ1 in a transcriptional hierarchy that directs this interneuron differentiation pathway. Moreover, ectopic RORβ1 expression in neonatal retina promotes amacrine cell differentiation. PMID:23652001

  16. Design and Application of Novel Horizontal Circulating Fluidized Bed Boiler

    NASA Astrophysics Data System (ADS)

    Lit, Q. H.; Zhang, Y. G.; Meng, A. H.

    The vertical circulating fluidized bed (CFB) boiler has been found wide application in power generation and tends to be enlarged in capacity. Because CFB is one of environment friendly and high efficiency combustion technologies, the CFB boiler has also been expected to be used in the industrial area, such as textile mill, region heating, brewery, seed drying and so on. However, the necessary height of furnace is hard to be implemented for CFB with especially small capacity. Thereby, a novel horizontal circulating fluidized bed boiler has been proposed and developed. The horizontal CFB is composed of primary combustion chamber, secondary combustion chamber, burnout chamber, cyclone, loop seal, heat recovery area. The primary combustion chamber is a riser like as that in vertical CFB, and the secondary combustion chamber is a downward passage that is a natural extension of the primary riser, which can reduce the overall height of the boiler. In some extent, the burnout chamber is also the extension of primary riser. The capacity of horizontal CFB is about 4.2-24.5MWth (6-35t/h) steam output or equivalent hot water supply. The hot water boiler of 7MWth and steam boilers of 4.2MWth (6t/h) and 10.5MWth (15t/h) are all designed and working well now. The three units of hot water horizontal CFB boiler were erected in the Neimenggu Autonomous Region, Huhehaote city for region heating. The three units of steam horizontal CFB has been installed in Yunnan, Jiang Xi and Guangdong provinces, respectively. The basic principle for horizontal CFB and experiences for designing and operating are presented in this paper. Some discussions are also given to demonstrate the promising future of horizontal CFB.

  17. Cleanup/stimulation of a horizontal wellbore using propellants

    SciTech Connect

    Rougeot, J.E.; Lauterbach, K.A.

    1993-01-01

    This report documents the stimulation/cleanup of a horizontal well bore (Wilson 25) using propellants. The Wilson 25 is a Bartlesville Sand well located in the Flatrock Field, Osage County, Oklahoma. The Wilson 25 was drilled to determine if horizontal drilling could be used as a means to economically recover primary oil that had been left in place in a mostly abandoned oil field because of the adverse effects of water coning. Pump testing of the Wilson 25 horizontal well bore before cleanup or stimulation produced 6 barrels of oil and .84 barrels of water per day. The high percentage of daily oil production to total daily fluid production indicated that the horizontal well bore had accessed potentially economical oil reserves if the fluid production rate could be increased by performing a cleanup/stimulation treatment. Propellants were selected as an inexpensive means to stimulate and cleanup the near well bore area in a uniform manner. The ignition of a propellant creates a large volume of gas which penetrates the formation, creating numerous short cracks through which hydrocarbons can travel into the well bore. More conventional stimulation/cleanup techniques were either significantly more expensive, less likely to treat uniformly, or could not be confined to the near well bore area. Three different propellant torpedo designs were tested with a total of 304' of horizontal well bore being shot and producible. The initial test shot caused 400' of the horizontal well bore to become plugged off, and subsequently it could not be production tested. The second and third test shots were production tested, with the oil production being increased 458% and 349%, respectively, on a per foot basis. The Wilson 25 results indicate that a propellant shot treatment is an economically viable means to cleanup/stimulate a horizontal well bore.

  18. Influence of sprint acceleration stance kinetics on velocity and step kinematics in field sport athletes.

    PubMed

    Lockie, Robert G; Murphy, Aron J; Schultz, Adrian B; Jeffriess, Matthew D; Callaghan, Samuel J

    2013-09-01

    The interaction between step kinematics and stance kinetics determines sprint velocity. However, the influence that stance kinetics has on effective acceleration in field sport athletes requires clarification. About 25 men (age = 22.4 ± 3.2 years; mass = 82.8 ± 7.2 kg; height = 1.81 ± 0.07 m) completed twelve 10-m sprints, 6 sprints each for kinematic and kinetic assessment. Pearson's correlations (p ≤ 0.05) examined relationships between 0-5, 5-10, and 0-10 m velocity; step kinematics (mean step length [SL], step frequency, contact time [CT], flight time over each interval); and stance kinetics (relative vertical, horizontal, and resultant force and impulse; resultant force angle; ratio of horizontal to resultant force [RatF] for the first, second, and last contacts within the 10-m sprint). Relationships were found between 0-5, 5-10, and 0-10 m SL and 0-5 and 0-10 m velocity (r = 0.397-0.535). CT of 0-5 and 0-10 m correlated with 5-10 m velocity (r = -0.506 and -0.477, respectively). Last contact vertical force correlated with 5-10 m velocity (r = 0.405). Relationships were established between the second and last contact vertical and resultant force and CT over all intervals (r = -0.398 to 0.569). First and second contact vertical impulse correlated with 0-5 m SL (r = 0.434 and 0.442, respectively). Subjects produced resultant force angles and RatF suitable for horizontal force production. Faster acceleration in field sport athletes involved longer steps, with shorter CT. Greater vertical force production was linked with shorter CT, illustrating efficient force production. Greater SLs during acceleration were facilitated by higher vertical impulse and appropriate horizontal force. Speed training for field sport athletes should be tailored to encourage these technique adaptations.

  19. Short‐term time step convergence in a climate model

    PubMed Central

    Rasch, Philip J.; Taylor, Mark A.; Jablonowski, Christiane

    2015-01-01

    Abstract This paper evaluates the numerical convergence of very short (1 h) simulations carried out with a spectral‐element (SE) configuration of the Community Atmosphere Model version 5 (CAM5). While the horizontal grid spacing is fixed at approximately 110 km, the process‐coupling time step is varied between 1800 and 1 s to reveal the convergence rate with respect to the temporal resolution. Special attention is paid to the behavior of the parameterized subgrid‐scale physics. First, a dynamical core test with reduced dynamics time steps is presented. The results demonstrate that the experimental setup is able to correctly assess the convergence rate of the discrete solutions to the adiabatic equations of atmospheric motion. Second, results from full‐physics CAM5 simulations with reduced physics and dynamics time steps are discussed. It is shown that the convergence rate is 0.4—considerably slower than the expected rate of 1.0. Sensitivity experiments indicate that, among the various subgrid‐scale physical parameterizations, the stratiform cloud schemes are associated with the largest time‐stepping errors, and are the primary cause of slow time step convergence. While the details of our findings are model specific, the general test procedure is applicable to any atmospheric general circulation model. The need for more accurate numerical treatments of physical parameterizations, especially the representation of stratiform clouds, is likely common in many models. The suggested test technique can help quantify the time‐stepping errors and identify the related model sensitivities. PMID:27660669

  20. A Step-by-Step Guide to Personalize Learning

    ERIC Educational Resources Information Center

    Bray, Barbara; McClaskey, Kathleen

    2013-01-01

    It is known that every learner is unique and that one-size-fits-all instruction does not work for most. How can a classroom environment be created that gives each learner voice and choice? The co-founders of Personalize Learning, LLC, offer a detailed six-step approach. This article provides the background on what is and what is not Personalized…

  1. Writing the Winning Dissertation: A Step-By-Step Guide.

    ERIC Educational Resources Information Center

    Glatthorn, Allan A.

    This book is a practical guide to researching and writing the doctoral dissertation or master's thesis. Part 1 offers seven chapters on preparatory steps: laying the groundwork for the thesis and dissertation; finding a research problem; conducting a focused review of the literature; making a preliminary choice of methodology; organizing and…

  2. Step fluctuations and step interactions on Mo(0 1 1)

    NASA Astrophysics Data System (ADS)

    Ondrejcek, M.; Swiech, W.; Durfee, C. S.; Flynn, C. P.

    2003-09-01

    Step fluctuations have been studied on Mo(0 1 1) thin single crystal films with various orientations of miscut, in order to determine the step stiffnesses. Effects of unseen defect structures were clearly visible in some data. Measurements of fluctuation amplitudes and relaxation times were made in the temperature range 1100-1680 K. The results show an anisotropic stiffness of about 0.36 eV/nm along [0 1¯ 1] and about 0.15 eV/nm along [1 0 0]. No temperature dependence of the stiffness was detected. The step free energies derived from the stiffnesses average about 0.27 eV/nm and are less anisotropic by about a factor 3. From the temperature dependence of the relaxation rates, an activation energy of 0.8 ± 0.2 eV was determined for the mass diffusion of the mobile defects responsible for the fluctuations. An appendix details an investigation of correlations induced in the motions of neighboring steps by diffusion and by energetic interactions.

  3. Publishing Ethical Research: A Step-by-Step Overview

    ERIC Educational Resources Information Center

    Wester, Kelly L.

    2011-01-01

    To publish ethical research, one must conduct research responsibly, making ethical choices from the inception of the research idea and throughout the research process. Conducting and publishing ethical research is important because of the impact the results will have on the counseling profession. Steps to consider are discussed.

  4. Cataloging Books Step by Step. CSLA Guide No. 5.

    ERIC Educational Resources Information Center

    Smith, Ruth S.

    Designed as a beginning, how-to guide, this handbook lists 20 short steps to cataloging library materials for a church or synagogue library. The guide opens with a history and a brief explanation of the Dewey Decimal System, with special attention given to the divisions and subdivisions that fall under the category "Religion." Several references…

  5. From raw material to dish: pasta quality step by step.

    PubMed

    Sicignano, Angelo; Di Monaco, Rossella; Masi, Paolo; Cavella, Silvana

    2015-10-01

    Pasta is a traditional Italian cereal-based food that is popular worldwide because of its convenience, versatility, sensory and nutritional value. The aim of this review is to present a step-by-step guide to facilitate the understanding of the most important events that can affect pasta characteristics, directing the reader to the appropriate production steps. Owing to its unique flavor, color, composition and rheological properties, durum wheat semolina is the best raw material for pasta production. Although pasta is traditionally made from only two ingredients, sensory quality and chemical/physical characteristics of the final product may vary greatly. Starting from the same ingredients, there are a lot of different events in each step of pasta production that can result in the development of varieties of pasta with different characteristics. In particular, numerous studies have demonstrated the importance of temperature and humidity conditions of the pasta drying operation as well as the significance of the choice of raw material and operating conditions on pasta quality. PMID:25783568

  6. Piezoelectric step-motion actuator

    DOEpatents

    Mentesana; Charles P.

    2006-10-10

    A step-motion actuator using piezoelectric material to launch a flight mass which, in turn, actuates a drive pawl to progressively engage and drive a toothed wheel or rod to accomplish stepped motion. Thus, the piezoelectric material converts electrical energy into kinetic energy of the mass, and the drive pawl and toothed wheel or rod convert the kinetic energy of the mass into the desired rotary or linear stepped motion. A compression frame may be secured about the piezoelectric element and adapted to pre-compress the piezoelectric material so as to reduce tensile loads thereon. A return spring may be used to return the mass to its resting position against the compression frame or piezoelectric material following launch. Alternative embodiment are possible, including an alternative first embodiment wherein two masses are launched in substantially different directions, and an alternative second embodiment wherein the mass is eliminated in favor of the piezoelectric material launching itself.

  7. Shapiro step at nonequilibrium conditions

    NASA Astrophysics Data System (ADS)

    Shukrinov, Yu. M.; Nashaat, M.; Kulikov, K. V.; Dawood, R.; El Samman, H.; El Sherbini, Th. M.

    2016-07-01

    Detailed numerical simulations of intrinsic Josephson junctions of high-temperature superconductors under external electromagnetic radiation are performed taking into account a charge imbalance effect. We demonstrate that the charge imbalance is responsible for a slope in the Shapiro step in the IV-characteristic. The value of slope increases with a nonequilibrium parameter. Coupling between junctions leads to the distribution of the slope's values along the stack. The nonperiodic boundary conditions shift the Shapiro step from the canonical position determined by Vss=\\hbar f /(2e) , where f is a frequency of external radiation. This fact makes the interpretation of the experimentally found Shapiro step shift by the charge imbalance effect ambiguous.

  8. MMH fluids reduce formation damage in horizontal wells

    SciTech Connect

    Fraser, L. ); Williamson, D. ); Haydel, S. )

    1994-02-01

    It has been more than 3 years since a mixed metal hydroxide fluid was used by Texaco to drill the Gulf of Mexico's first horizontal hole. Since, the fluid has been used to drill dozens of horizontal sections worldwide, including Australia, Indonesia, CIS, UAE, UK, and in North an South America. Due to Texaco's drilling success on the first Gulf of Mexico horizontal well in 1990, several horizontal wells were drilled in the Gulf's shallow gas sands. Fluids were weighted exclusively with ground marble. The marble, with measured grind size distributions similar to commercial barite, is used as a combination weighting and bridging material and is about 99% acid soluble. Completions were carried out by running a slotted liner, displacing the mixed metal hydroxide (MMH) fluid with calcium chloride brine, and running prepacked screens. Clean-up times where short and production rates equaled or exceeded expectations. Since the technique was relatively new, no comparisons could be made. One operator, however, achieved success during 18 months of production. During this period, the fluid was also used to drill a horizontal section through the Cardium Sandstone at Lodgepole in Alberta, Canada. The fluid out-performed other in return permeability tests on cores from the reservoir. Its performance was enhanced by addition of propylene glycol. High field production rates supported laboratory findings.

  9. Pathologic diagnosis of central centrifugal cicatricial alopecia on horizontal sections.

    PubMed

    Miteva, Mariya; Tosti, Antonella

    2014-11-01

    The pathologic findings in Central Centrifugal Cicatricial Alopecia (CCCA) have not been studied systematically in horizontal sections. Our objective was to establish the pathologic features, and their frequency in horizontal sections of scalp biopsies obtained from patients with clinically and histologically proven CCCA. Serial horizontal sections of 51 cases were evaluated retrospectively. All biopsies were assessed at 4 levels and at least on 24 horizontal sections. The most common pathologic findings were follicular miniaturization (81% of the cases); premature desquamation of the inner root sheath (96%), focal preservation of the sebaceous glands (94%), which in most of these cases appeared as surrounding "in a hug" an intact vellus follicle; compound follicular structures with perifollicular fibrosis and/or inflammation (89%), lamellar hyperkeratosis/parakeratosis in the hair canal (79%), absent or mild inflammation (77%), and naked hair shafts (68%). Horizontal sections are useful in CCCA to identify early or focal disease and to provide the clinician with better information on the presence of follicular miniaturization, inflammation, and scarring, which can be used to tailor the treatment to the individual patient.

  10. Effects of vertical shear in modelling horizontal oceanic dispersion

    NASA Astrophysics Data System (ADS)

    Lanotte, A. S.; Corrado, R.; Palatella, L.; Pizzigalli, C.; Schipa, I.; Santoleri, R.

    2016-02-01

    The effect of vertical shear on the horizontal dispersion properties of passive tracer particles on the continental shelf of the South Mediterranean is investigated by means of observation and model data. In situ current measurements reveal that vertical gradients of horizontal velocities in the upper mixing layer decorrelate quite fast ( ˜ 1 day), whereas an eddy-permitting ocean model, such as the Mediterranean Forecasting System, tends to overestimate such decorrelation time because of finite resolution effects. Horizontal dispersion, simulated by the Mediterranean sea Forecasting System, is mostly affected by: (1) unresolved scale motions, and mesoscale motions that are largely smoothed out at scales close to the grid spacing; (2) poorly resolved time variability in the profiles of the horizontal velocities in the upper layer. For the case study we have analysed, we show that a suitable use of deterministic kinematic parametrizations is helpful to implement realistic statistical features of tracer dispersion in two and three dimensions. The approach here suggested provides a functional tool to control the horizontal spreading of small organisms or substance concentrations, and is thus relevant for marine biology, pollutant dispersion as well as oil spill applications.

  11. A heat transfer model of a horizontal ground heat exchanger

    NASA Astrophysics Data System (ADS)

    Mironov, R. E.; Shtern, Yu. I.; Shtern, M. Yu.; Rogachev, M. S.

    2016-04-01

    Ground-source heat pumps are gaining popularity in Eastern Europe, especially those which are using the horizontal ground heat exchanger (GHX). Due to the difficulty of accessing GHX after the installation, materials and the quality of the installation must satisfy the very high requirements. An inaccurate calculation of GHX can be the reason of a scarcity of heat power in a crucial moment. So far, there isn't any appropriate mathematical description of the horizontal GHX which takes into account the mutual influence of GHX pipes on each other. To solve this problem we used the temperature wave approach. As a result, a mathematical model which describes the dependence of the heat transfer rate per unit length of the horizontal GHX pipe on the thermal properties of soil, operating time of GHX and the distance between pipes was obtained. Using this model, heat transfer rates per unit length of a horizontal GHX were plotted as functions of the distance between pipes and operating time. The modeling shows that heat transfer rates decreases rapidly with the distance between pipes lower then 2 meters. After the launch of heat pump, heat power of GHX is reduced during the first 20 - 30 days and get steady after that. The obtained results correlate with experimental data. Therefore the proposed mathematical model can be used to design a horizontal GHX with the optimal characteristics, and predict its capability during operation.

  12. Pathologic diagnosis of central centrifugal cicatricial alopecia on horizontal sections.

    PubMed

    Miteva, Mariya; Tosti, Antonella

    2014-11-01

    The pathologic findings in Central Centrifugal Cicatricial Alopecia (CCCA) have not been studied systematically in horizontal sections. Our objective was to establish the pathologic features, and their frequency in horizontal sections of scalp biopsies obtained from patients with clinically and histologically proven CCCA. Serial horizontal sections of 51 cases were evaluated retrospectively. All biopsies were assessed at 4 levels and at least on 24 horizontal sections. The most common pathologic findings were follicular miniaturization (81% of the cases); premature desquamation of the inner root sheath (96%), focal preservation of the sebaceous glands (94%), which in most of these cases appeared as surrounding "in a hug" an intact vellus follicle; compound follicular structures with perifollicular fibrosis and/or inflammation (89%), lamellar hyperkeratosis/parakeratosis in the hair canal (79%), absent or mild inflammation (77%), and naked hair shafts (68%). Horizontal sections are useful in CCCA to identify early or focal disease and to provide the clinician with better information on the presence of follicular miniaturization, inflammation, and scarring, which can be used to tailor the treatment to the individual patient. PMID:25222198

  13. Automated Tracing of Horizontal Neuron Processes During Retinal Development

    SciTech Connect

    Kerekes, Ryan A; Martins, Rodrigo; Dyer, Michael A; Gleason, Shaun Scott; Karakaya, Mahmut; Davis, Denise

    2011-01-01

    In the developing mammalian retina, horizontal neurons undergo a dramatic reorganization oftheir processes shortly after they migrate to their appropriate laminar position. This is an importantprocess because it is now understood that the apical processes are important for establishing theregular mosaic of horizontal cells in the retina and proper reorganization during lamination isrequired for synaptogenesis with photoreceptors and bipolar neurons. However, this process isdifficult to study because the analysis of horizontal neuron anatomy is labor intensive and time-consuming. In this paper, we present a computational method for automatically tracing the three-dimensional (3-D) dendritic structure of horizontal retinal neurons in two-photon laser scanningmicroscope (TPLSM) imagery. Our method is based on 3-D skeletonization and is thus able topreserve the complex structure of the dendritic arbor of these cells. We demonstrate theeffectiveness of our approach by comparing our tracing results against two sets of semi-automatedtraces over a set of 10 horizontal neurons ranging in age from P1 to P5. We observe an averageagreement level of 81% between our automated trace and the manual traces. This automatedmethod will serve as an important starting point for further refinement and optimization.

  14. The interconnection between biofilm formation and horizontal gene transfer.

    PubMed

    Madsen, Jonas Stenløkke; Burmølle, Mette; Hansen, Lars Hestbjerg; Sørensen, Søren Johannes

    2012-07-01

    Recent research has revealed that horizontal gene transfer and biofilm formation are connected processes. Although published research investigating this interconnectedness is still limited, we will review this subject in order to highlight the potential of these observations because of their believed importance in the understanding of the adaptation and subsequent evolution of social traits in bacteria. Here, we discuss current evidence for such interconnectedness centred on plasmids. Horizontal transfer rates are typically higher in biofilm communities compared with those in planktonic states. Biofilms, furthermore, promote plasmid stability and may enhance the host range of mobile genetic elements that are transferred horizontally. Plasmids, on the other hand, are very well suited to promote the evolution of social traits such as biofilm formation. This, essentially, transpires because plasmids are independent replicons that enhance their own success by promoting inter-bacterial interactions. They typically also carry genes that heighten their hosts' direct fitness. Furthermore, current research shows that the so-called mafia traits encoded on mobile genetic elements can enforce bacteria to maintain stable social interactions. It also indicates that horizontal gene transfer ultimately enhances the relatedness of bacteria carrying the mobile genetic elements of the same origin. The perspective of this review extends to an overall interconnectedness between horizontal gene transfer, mobile genetic elements and social evolution of bacteria.

  15. Horizontal transfer of DNA methylation patterns into bacterial chromosomes

    PubMed Central

    Shin, Jung-Eun; Lin, Chris; Lim, Han N.

    2016-01-01

    Horizontal gene transfer (HGT) is the non-inherited acquisition of novel DNA sequences. HGT is common and important in bacteria because it enables the rapid generation of new phenotypes such as antibiotic resistance. Here we show that in vivo and in vitro DNA methylation patterns can be horizontally transferred into bacterial chromosomes to program cell phenotypes. The experiments were performed using a synthetic system in Escherichia coli where different DNA methylation patterns within the cis-regulatory sequence of the agn43 gene turn on or off a fluorescent reporter (CFP). With this system we demonstrated that DNA methylation patterns not only accompany the horizontal transfer of genes into the bacterial cytoplasm but can be transferred into chromosomes by: (i) bacteriophage P1 transduction; and (ii) transformation of extracellular synthetic DNA. We also modified the experimental system by replacing CFP with the SgrS small RNA, which regulates glucose and methyl α-D-glucoside uptake, and showed that horizontally acquired DNA methylation patterns can increase or decrease cell fitness. That is, horizontally acquired DNA methylation patterns can result in the selection for and against cells that have HGT. Findings from these proof-of-concept experiments have applications in synthetic biology and potentially broad implications for bacterial adaptation and evolution. PMID:27084942

  16. Influence of pavement condition on horizontal curve safety.

    PubMed

    Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A

    2013-03-01

    Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments.

  17. Influence of pavement condition on horizontal curve safety.

    PubMed

    Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A

    2013-03-01

    Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments. PMID:23298704

  18. Applicability of the polysulphone horizontal calibration to differently inclined dosimeters.

    PubMed

    Casale, Giuseppe R; Siani, Anna Maria; Diémoz, Henri; Kimlin, Michael G; Colosimo, Alfredo

    2012-01-01

    Polysulphone (PS) dosimetry has been a widely used technique for more than 30 years to quantify the erythemally effective UV dose received by anatomic sites (personal exposure). The calibration of PS dosimeters is an important issue as their spectral response is different from the erythemal action spectrum. It is performed exposing a set of PS dosimeters on a horizontal plane and measuring the UV doses received by dosimeters using calibrated spectroradiometers or radiometers. In this study, data collected during PS field campaigns (from 2004 to 2006), using horizontal and differently inclined dosimeters, were analyzed to provide some considerations on the transfer of the horizontal calibration to differently inclined dosimeters, as anatomic sites usually are. The role of sky conditions, of the angle of incidence between the sun and the normal to the slope, and of the type of surrounding surface on the calibration were investigated. It was concluded that PS horizontal calibrations apply to differently inclined dosimeters for incidence angles up to approximately 70° and for surfaces excluding ones with high albedo. Caution should be used in the application of horizontal calibrations for cases of high-incidence angle and/or high albedo surfaces.

  19. Approximation for Horizontal Photon Transport in Cloud Remote Sensing Problems

    NASA Technical Reports Server (NTRS)

    Plantnick, Steven

    1999-01-01

    The effect of horizontal photon transport within real-world clouds can be of consequence to remote sensing problems based on plane-parallel cloud models. An analytic approximation for the root-mean-square horizontal displacement of reflected and transmitted photons relative to the incident cloud-top location is derived from random walk theory. The resulting formula is a function of the average number of photon scatterings, and particle asymmetry parameter and single scattering albedo. In turn, the average number of scatterings can be determined from efficient adding/doubling radiative transfer procedures. The approximation is applied to liquid water clouds for typical remote sensing solar spectral bands, involving both conservative and non-conservative scattering. Results compare well with Monte Carlo calculations. Though the emphasis is on horizontal photon transport in terrestrial clouds, the derived approximation is applicable to any multiple scattering plane-parallel radiative transfer problem. The complete horizontal transport probability distribution can be described with an analytic distribution specified by the root-mean-square and average displacement values. However, it is shown empirically that the average displacement can be reasonably inferred from the root-mean-square value. An estimate for the horizontal transport distribution can then be made from the root-mean-square photon displacement alone.

  20. Coordination of axial rotation and step execution: deficits in Parkinson's disease.

    PubMed

    Vaugoyeau, M; Viallet, F; Mesure, S; Massion, J

    2003-12-01

    To determine why parkinsonian patients (PP) present some difficulties to initiate locomotion, a diagonal step has been investigated in two tasks in five control subjects (CS) and in ten PP. In the first task, the subjects had to perform one diagonal step without change in their orientation (WR); in the second task, they had to perform one diagonal step with a body rotation in the step direction (RO). The defended hypothesis is that the gait initiation deficits in Parkinson disease are a consequence of their difficulties to coordinate al the component of a complex movement. The analysed parameters were the duration of the postural and movement phases, the step length and velocity, and the amplitude of the horizontal ground reaction forces during each phase. Compared to CS, the PP showed a lengthening of the postural phase, a decrease in the step length and velocity and a reduction of the horizontal forces. The comparisons between the performances obtained in the WR versus those obtained the RO show in CS that the performances remained unchanged, whereas in PP the performances were significantly more altered in the RO. It illustrates the specific deficit occurring in PP while performing complex tasks where coordination between several components has to be achieved simultaneously.

  1. Contribution to the Study of Ferrite Nanobeads: Synthesis, Characterization and Investigation of Horizontal Low Gradient Magnetophoresis Behaviour

    SciTech Connect

    Benelmekki, Maria; Caparros, Cristina; Goncalves, Renao; Lanceros-Mendez, Senenxu; Montras, Anna; Martinez, Lluis Miquel

    2010-12-02

    In this work we investigate the possibilities of the use of Horizontal Low Gradient Magnetic Field (HLGMF)(<100 T/m) for filtration, control and separation of the synthesized magnetic particles, considering, the characteristics of the suspension, the size and the type of nanoparticles (NPs) and focusing on the process scale up. Reversible aggregation is considered in the different steps of magnetic nanobeads synthesis. For these purpose, we synthesized Fe{sub 2}O{sub 3}-silica core-shell nanobeads by co-precipitation, monodispersion and silica coating. SQUID, TEM, XRD, and Zeta potential techniques were used to characterize the synthesized nanobeads. An extensive magnetophoresis study was performed at different magnetophoretic conditions. Different reversible aggregation times were observed at different HLGMF, at each step of the synthesis route: Several orders of magnitude differences where observed when comparing citric acid (CA) suspension with silicon coated beads. Reversible aggregation times are correlated with the properties of the NPs at different steps of synthesis.

  2. Calculation of area-averaged vertical profiles of the horizontal wind velocity from volume-imaging lidar data

    NASA Technical Reports Server (NTRS)

    Schols, J. L.; Eloranta, E. W.

    1992-01-01

    Area-averaged horizontal wind measurements are derived from the motion of spatial inhomogeneities in aerosol backscattering observed with a volume-imaging lidar. Spatial averaging provides high precision, reducing sample variations of wind measurements well below the level of turbulent fluctuations, even under conditions of very light mean winds and strong convection or under the difficult conditions represented by roll convection. Wind velocities are measured using the two-dimensional spatial cross correlation computed between successive horizontal plane maps of aerosol backscattering, assembled from three-dimensional lidar scans. Prior to calculation of the correlation function, three crucial steps are performed: (1) the scans are corrected for image distortion by the wind during a finite scan time; (2) a temporal high pass median filtering is applied to eliminate structures that do not move with the wind; and (3) a histogram equalization is employed to reduce biases to the brightest features.

  3. On the role of horizontal displacements in the exhumation of high pressure metamorphic rocks

    NASA Astrophysics Data System (ADS)

    Brun, J.-P.; Tirel, C.; Philippon, M.; Burov, E.; Faccenna, C.; Gueydan, F.; Lebedev, S.

    2012-04-01

    High pressure metamorphic rocks exposed in the core of many mountain belts correspond to various types of upper crustal materials that have been buried to mantle depths and, soon after, brought back to surface at mean displacement rates up to few cm/y, comparable to those of plate boundaries. The vertical component of HP rock exhumation velocity back to surface is commonly well constrained by pressure estimates from petrology and geochronological data whereas the horizontal component remains generally difficult or impossible to estimate. Consequently, most available models, if not all, attempt to simulate exhumation with a minimal horizontal component of displacement. Such models, require that the viscosity of HP rocks is low and/or the erosion rate large -i.e. at least equal to the rate of exhumation. However, in some regions like the Aegean, where the exhumation of blueschists and eclogites is driven by slab rollback, it can be shown that the horizontal component of exhumation related displacement, obtained from map view restoration, is 5 to 7 times larger than the vertical one, deduced from metamorphic pressure estimates. Using finite element models performed with FLAMAR, we show that such a situation simply results from the subduction of small continental blocks (< 500km) that stimulate subduction rollback. The continental block is dragged downward and sheared off the downgoing mantle slab by buoyancy force. Exhumation of the crustal block occurs through a one step Caterpillar-type walk, with the block's tail slipping along a basal décollement, approaching the head and making a large buckle, which then unrolls at surface as soon as the entire block is delaminated. Finally, the crustal block emplaces at surface in the space created by trench retreat. This process of exhumation requires neither rheological weakening of HP rocks nor high rates of erosion.

  4. Effect of Target Location on Dynamic Visual Acuity During Passive Horizontal Rotation

    NASA Technical Reports Server (NTRS)

    Appelbaum, Meghan; DeDios, Yiri; Kulecz, Walter; Peters, Brian; Wood, Scott

    2010-01-01

    The vestibulo-ocular reflex (VOR) generates eye rotation to compensate for potential retinal slip in the specific plane of head movement. Dynamic visual acuity (DVA) has been utilized as a functional measure of the VOR. The purpose of this study was to examine changes in accuracy and reaction time when performing a DVA task with targets offset from the plane of rotation, e.g. offset vertically during horizontal rotation. Visual acuity was measured in 12 healthy subjects as they moved a hand-held joystick to indicate the orientation of a computer-generated Landolt C "as quickly and accurately as possible." Acuity thresholds were established with optotypes presented centrally on a wall-mounted LCD screen at 1.3 m distance, first without motion (static condition) and then while oscillating at 0.8 Hz (DVA, peak velocity 60 deg/s). The effect of target location was then measured during horizontal rotation with the optotypes randomly presented in one of nine different locations on the screen (offset up to 10 deg). The optotype size (logMar 0, 0.2 or 0.4, corresponding to Snellen range 20/20 to 20/50) and presentation duration (150, 300 and 450 ms) were counter-balanced across five trials, each utilizing horizontal rotation at 0.8 Hz. Dynamic acuity was reduced relative to static acuity in 7 of 12 subjects by one step size. During the random target trials, both accuracy and reaction time improved proportional to optotype size. Accuracy and reaction time also improved between 150 ms and 300 ms presentation durations. The main finding was that both accuracy and reaction time varied as a function of target location, with greater performance decrements when acquiring vertical targets. We conclude that dynamic visual acuity varies with target location, with acuity optimized for targets in the plane of motion. Both reaction time and accuracy are functionally relevant DVA parameters of VOR function.

  5. Slim-hole casing program adapted to horizontal well

    SciTech Connect

    Foster, L. )

    1993-09-06

    A type of slim-hole well design reduced the cost of drilling a horizontal well in the southern North Sea. The basic slim-hole drilling and casing program was similar to that used in conventional directional wells in the field, but with slight modifications for drilling with logging-while-drilling (LWD) tools and running production liners. Nearly 2,600 ft were successfully drilled at over 80[degree] inclination in ARCO British Ltd.'s Pickerill A6 well, the first time in the southern North Sea that a horizontal well was drilled through the reservoir without first casting off the overlying evaporite sequence. The paper describes the well design, the pilot hole plan, the evaluation program for directional drilling, a horizontal sidetrack plan, its evaluation and drilling, hole conditions, liners, well completion, and results.

  6. Horizontal well drilled into deep, hot Austin chalk

    SciTech Connect

    Pearce, D.; Johnson, M.; Godfrey, B.

    1995-04-03

    Bent-housing steerable downhole motors helped maintain course for a deep, hot, horizontal well in the Austin chalk. The Navasota Unit No. 1 was planned as a B zone, single downdip lateral, Austin chalk horizontal well with a maximum departure from vertical of 3,767 ft and a planned total depth (TD) of 17,342 ft measured depth (MD)/14,172 ft TVD. The Austin chalk was found significantly deeper in this well than planned, which resulted in an actual TD of 17,899 ft MD/14,993 ft TVD, the deepest (TVD) horizontal well in the Austin chalk to date. The well was spudded on August 6, 1994, and took 52 days to reach TD. The static bottom hole temperature was almost 350 F. The paper describes the well plan, drilling results, and the lateral section.

  7. Numerical Modelling of the Mining Induced Horizontal Displacement

    NASA Astrophysics Data System (ADS)

    Tajduś, Krzysztof

    2015-12-01

    The paper presents results of numerical calculations and modeling of mining-induced surface deformation based on Finite Element Method (FEM). Applying the numerical method discussed to calculations allows us to assume a larger number of factors, such as rock mass structure, fracture network, rock properties, etc., which essentially affect the results obtained. On the basis of an elastic transversely isotropic model, an analysis of horizontal displacement distribution and surface subsidence was carried out for two sample regions of mines. The results of numerical calculations were later compared with the measured values. Such an analysis proved that the applied numerical model properly described distribution and values of subsidence and slope of subsidence trough, though there were serious differences in the values of calculated horizontal displacement, especially in areas of far influence range. In order to improve the matching, the influence of boundary conditions of the model on the value of calculated horizontal displacement was analyzed. The results are presented in graphs.

  8. High-performance horizontal side scanner using holographic technology

    NASA Astrophysics Data System (ADS)

    Cheng, Charles C. K.

    1998-06-01

    A new holographic technique has been used to make a compact, accurate and reliable POS scanner. The holo-window technology permits compact POS scanner optical scanning in horizontal plan while maintaining excellent performance in changing the scan direction, equalizing the scan velocity and collecting the signal light. The holo-window design and fabrication in the holographic optical element (HOE) for such a compact POS scanner are described in this paper. Additionally this new horizontal side scanning possesses large depth of field (greater than 10 inches), allows the grocery items to be scanned horizontally thus eliminating the commonly experienced carpal tunnel syndrome (CTS) hand injuries of the checkers. This newly designed POS scanner has been recognized by industry as the standard for the future POS scanning configuration.

  9. Horizontal and vertical reading: a comparative investigation of eye movements.

    PubMed

    Schmidt, D; Ullrich, D; Rossner, R

    1993-08-01

    Electronystagmographic (ENG) recordings of eye movements were made during the horizontal and vertical reading of a standardized text. The text was rotated to one side through an angle of 90 degrees for vertical reading. A total of 35 normal subjects was investigated under identical conditions. The following differences were found: A "staircase" pattern of successive, remarkably regular eye jerks was observed during horizontal reading. The reading speed was significantly higher in the horizontal direction. Vertical eye movements during vertical reading were less regular and showed a greater number of small jerks of varying size. No significant difference in reading speed between the two vertical directions was found. The search coil method (Robinson), which was employed in one subject, yielded much more accurate recordings than did the ENG. As a control experiment for vertical reading, the letters were rotated through 90 degrees. Reading this transposed text took twice as long as reading a 90 degrees-rotated text.

  10. Contrast between the vertical and horizontal mercury discharge lamps

    SciTech Connect

    Ben Hamida, M. B.; Helali, H.; Araoud, Z.; Charrada, K.

    2011-06-15

    This paper discusses the thermal behavior of a high pressure mercury lamp in a horizontal position, compared with that of a vertical lamp. The model adopted is three-dimensional, steady, and powered DC. After the model validation, we analyzed temperature fields and velocities for the case of the lamp in a horizontal position by comparing it with those of a lamp in vertical position. This setting initially fixed the wall temperature equal to 1000 K. However, the morphology of the temperature profile in the case of the horizontal lamp indicates that the temperature of the wall cannot be uniform. Thus, we have, in a second time, performed an energy balance at the wall to calculate its temperature. This aims to understand the influence of convection on the thermal properties of the source.

  11. Seven Steps to Successful Inclusion.

    ERIC Educational Resources Information Center

    Whitworth, Jerry

    This report highlights the experiences of the Lighthouse Project, which successfully included students with disabilities in elementary, middle, and high school general education classes in a school district in southwest Tennessee. Drawing on findings from the Lighthouse Project, the report describes the following seven steps that must be present…

  12. Steps to Maturity Program. Evaluation.

    ERIC Educational Resources Information Center

    Nanaimo School District #68 (British Columbia).

    In fall 1989, the Nanaimo (British Columbia) School District No. 68 asked five people, selected from the school system and community, to evaluate the "Steps to Maturity" Program (STMP), a district-wide family life education and affective development program that has developed gradually since 1972. The evaluation team interviewed a large number of…

  13. Evaluation of Florida's STEP Program.

    ERIC Educational Resources Information Center

    Florida State Dept. of Health and Rehabilitative Services, Tallahassee.

    Project STEP (Short Term Elective Program) is an outdoor-educational program that, through teaching wilderness survival skills and affording a necessity for their use, provides juvenile delinquents with a feeling of self-reliance and self-worth. The program is designed for committed youths, primarily males, at least 13 to 14 years of age, but…

  14. Ten Steps to "TQM Plus."

    ERIC Educational Resources Information Center

    Kaufman, Roger; Hirumi, Atsusi

    1992-01-01

    Total Quality Management Plus (TQM) goes beyond customer satisfaction to consider quality of life, environmental conditions, crime rates, and health and well-being. Steps to integrate such concerns into the TQM process include being ready for challenges, creating a quality system to collect performance data, defining the ideal school and world…

  15. Pride Is the First Step

    ERIC Educational Resources Information Center

    Rourke, James; Boone, Elizabeth

    2008-01-01

    When visitors step inside Pocomoke (MD) Middle School, they are immediately surrounded by a profound sense of pride and high expectations. Students are actively engaged in instruction, the classroom walls are covered with student work, and the halls are lined with pictures of students demonstrating success. Beanbag chairs await eager readers,…

  16. One-Step Coal Liquefaction

    NASA Technical Reports Server (NTRS)

    Qader, S. A.

    1984-01-01

    Steam injection improves yield and quality of product. Single step process for liquefying coal increases liquid yield and reduces hydrogen consumption. Principal difference between this and earlier processes includes injection of steam into reactor. Steam lowers viscosity of liquid product, so further upgrading unnecessary.

  17. 10 Steps for Implementing Change.

    ERIC Educational Resources Information Center

    Marsee, Jeff

    2002-01-01

    Offers steps for adapting the change process to institutional culture: align leadership style with organizational culture, don't overuse change missionaries, protect change agents, define the problem, maintain focus when the project drifts, identify and remove barriers before implementing action plans, assign responsibilities to individuals,…

  18. Initial steps of aerosol growth

    NASA Astrophysics Data System (ADS)

    Kulmala, M.; Laakso, L.; Lehtinen, K. E. J.; Riipinen, I.; Dal Maso, M.; Anttila, T.; Kerminen, V.-M.; Hõrrak, U.; Vana, M.; Tammet, H.

    2004-12-01

    The formation and growth of atmospheric aerosols depend on several steps, namely nucleation, initial steps of growth and subsequent - mainly condensational - growth. This work focuses on the initial steps of growth, meaning the growth right after nucleation, where the interplay of curvature effects and thermodynamics has a significant role on the growth kinetics. More specifically, we investigate how ion clusters and aerosol particles grow from 1.5 nm to 20 nm (diameter) in atmospheric conditions using experimental data obtained by air ion and aerosol spectrometers. The measurements have been performed at a boreal forest site in Finland. The observed trend that the growth rate seems to increase as a function of size can be used to investigate possible growth mechanisms. Such a growth rate is consistent with a recently suggested nano-Köhler mechanism, in which growth is activated at a certain size with respect to condensation of organic vapors. The results also imply that charge-enhanced growth associated with ion-mediated nucleation plays only a minor role in the initial steps of growth, since it would imply a clear decrease of the growth rate with size. Finally, further evidence was obtained on the earlier suggestion that atmospheric nucleation and the subsequent growth of fresh nuclei are likely to be uncoupled phenomena via different participating vapors.

  19. Initial steps of aerosol growth

    NASA Astrophysics Data System (ADS)

    Kulmala, O.; Laakso, L.; Lehtinen, K. E. J.; Riipinen, I.; Dal Maso, M.; Anttila, T.; Kerminen, V.-M.; Hõrrak, U.; Vana, M.; Tammet, H.

    2004-09-01

    The formation and growth of atmospheric aerosols depend on several steps, namely nucleation, initial steps of growth and subsequent - mainly condensational - growth. This work focuses on the initial steps of growth, meaning the growth right after nucleation, where the interplay of curvature effects and thermodynamics has a significant role on the growth kinetics. More specifically, we investigate how ion clusters and aerosol particles grow from 1.5 nm to 20 nm in atmospheric conditions using experimental data obtained by air ion and aerosol spectrometers. The measurements have been performed at a boreal forest site in Finland. The observed trend that the growth rate seems to increase as a function of size can be used to investigate possible growth mechanisms. Such a growth rate is consistent with a recently suggested nano-Köhler mechanism, in which growth is activated at a certain size with respect to condensation of organic vapors. The results also imply that charge-enhance growth associated with ion-mediated nucleation plays only a minor role in the initial steps of growth, since it would imply a clear decrease of the growth rate with size. Finally, further evidence was obtained on the earlier suggestion that atmospheric nucleation and the subsequent growth of fresh nuclei are likely to be uncoupled phenomena via different participating vapors.

  20. Five questions to consider before conducting a stepped wedge trial.

    PubMed

    Hargreaves, James R; Copas, Andrew J; Beard, Emma; Osrin, David; Lewis, James J; Davey, Calum; Thompson, Jennifer A; Baio, Gianluca; Fielding, Katherine L; Prost, Audrey

    2015-08-17

    Researchers should consider five questions before starting a stepped wedge trial. Why are you planning one? Researchers sometimes think that stepped wedge trials are useful when there is little doubt about the benefit of the intervention being tested. However, if the primary reason for an intervention is to measure its effect, without equipoise there is no ethical justification for delaying implementation in some clusters. By contrast, if you are undertaking pragmatic research, where the primary reason for rolling out the intervention is for it to exert its benefits, and if phased implementation is inevitable, a stepped wedge trial is a valid option and provides better evidence than most non-randomized evaluations. What design will you use? Two common stepped wedge designs are based on the recruitment of a closed or open cohort. In both, individuals may experience both control and intervention conditions and you should be concerned about carry-over effects. In a third, continuous-recruitment, short-exposure design, individuals are recruited as they become eligible and experience either control or intervention condition, but not both. How will you conduct the primary analysis? In stepped wedge trials, control of confounding factors through secular variation is essential. 'Vertical' approaches preserve randomization and compare outcomes between randomized groups within periods. 'Horizontal' approaches compare outcomes before and after crossover to the intervention condition. Most analysis models used in practice combine both types of comparison. The appropriate analytic strategy should be considered on a case-by-case basis. How large will your trial be? Standard sample size calculations for cluster randomized trials do not accommodate the specific features of stepped wedge trials. Methods exist for many stepped wedge designs, but simulation-based calculations provide the greatest flexibility. In some scenarios, such as when the intracluster correlation coefficient is

  1. Is angular momentum in the horizontal plane during gait a controlled variable?

    PubMed

    Thielemans, Valerie; Meyns, Pieter; Bruijn, Sjoerd M

    2014-04-01

    It has been suggested that angular momentum in the horizontal plane during human gait is controlled (i.e., kept minimal). However, this has not been explored in conditions when angular momentum of different segments is manipulated explicitly. In order to examine the behavior of angular momentum, 12 participants walked in 17 conditions in which angular momentum of either the arms or legs was manipulated. Subjects walked at different step lengths, different speeds and with an additional weight on either the wrist or ankle. Angular momentum of total body, arms and legs was calculated from gait kinematics. Increasing step length increased total body and leg angular momentum. When weight was added to the limbs, arm and leg angular momentum were affected and counteracted each other, so that total body angular momentum did not change. Moreover, increasing walking speed increased arm, leg and total body angular momentum. Thus, it may be concluded that if angular momentum is controlled (which only seems to be the case for conditions when weights are added), it is not strictly controlled in all gait conditions (as it may increase by walking faster/with larger steps).

  2. Modeling Horizontal GPS Seasonal Signals Caused by Ocean Loading

    NASA Astrophysics Data System (ADS)

    Bartlow, N. M.; Fialko, Y. A.

    2014-12-01

    GPS monuments around the world exhibit seasonal signals in both the horizontal and vertical components with amplitudes on the order of centimeters. For analysis of tectonic signals, researchers typically fit and remove a sine wave with an annual period, and sometimes an additional sine wave with a semiannual period. As interest grows in analyzing smaller, slower signals it becomes more important to correct for these seasonal signals accurately. It is well established that the vertical component of seasonal GPS signals is largely due to continental water storage cycles (e.g. van Dam et al., GRL, 2001). Horizontal seasonal signals however are not well explained by continental water storage. We examine horizontal seasonal signals across western North America and find that the horizontal component is coherent at very large spatial scales and is in general oriented perpendicular to the nearest coastline, indicating an oceanic origin. Additionally, horizontal and vertical annual signals are out of phase by approximately 2 months indicating different physical origins. Studies of GRACE and ocean bottom pressure data indicate an annual variation of non-steric, non-tidal ocean height with an average amplitude of 1 cm globally (e.g. Ponte et al., GRL, 2007). We use Some Programs for Ocean Tide Loading (SPOTL; Agnew, SIO Technical Report, 2012) to model predicted displacements due to these (non-tidal) ocean loads and find general agreement with observed horizontal GPS seasonal signals. In the future, this may lead to a more accurate way to predict and remove the seasonal component of GPS displacement time-series, leading to better discrimination of the true tectonic signal. Modeling this long wavelength signal also provides a potential opportunity to probe the structure of the Earth.

  3. Near-term Horizontal Launch for Flexible Operations: Results of the DARPA/NASA Horizontal Launch Study

    NASA Technical Reports Server (NTRS)

    Bartolotta, Paul A.; Wilhite, Alan W.; Schaffer, Mark G.; Huebner, Lawrence D.; Voland, Randall T.; Voracek, David F.

    2012-01-01

    Horizontal launch has been investigated for 60 years by over 130 different studies. During this time only one concept, Pegasus, has ever been in operation. The attractiveness of horizontal launch is the capability to provide a "mobile launch pad" that can use existing aircraft runways, cruise above weather, loiter for mission instructions, and provide precise placement for orbital intercept, rendezvous, or reconnaissance. A jointly sponsored study by DARPA and NASA, completed in 2011, explored the trade space of horizontal launch system concepts which included an exhaustive literature review of the past 70 years. The Horizontal Launch Study identified potential near- and mid-term concepts capable of delivering 15,000 lb payloads to a 28.5 due East inclination, 100 nautical-mile low-Earth orbit. Results are presented for a range of near-term system concepts selected for their availability and relatively low design, development, test, and evaluation (DDT&E) costs. This study identified a viable low-cost development path forward to make a robust and resilient horizontal launch capability a reality.

  4. 2-Step IMAT and 2-Step IMRT in three dimensions

    SciTech Connect

    Bratengeier, Klaus

    2005-12-15

    In two dimensions, 2-Step Intensity Modulated Arc Therapy (2-Step IMAT) and 2-Step Intensity Modulated Radiation Therapy (IMRT) were shown to be powerful methods for the optimization of plans with organs at risk (OAR) (partially) surrounded by a target volume (PTV). In three dimensions, some additional boundary conditions have to be considered to establish 2-Step IMAT as an optimization method. A further aim was to create rules for ad hoc adaptations of an IMRT plan to a daily changing PTV-OAR constellation. As a test model, a cylindrically symmetric PTV-OAR combination was used. The centrally placed OAR can adapt arbitrary diameters with different gap widths toward the PTV. Along the rotation axis the OAR diameter can vary, the OAR can even vanish at some axis positions, leaving a circular PTV. The width and weight of the second segment were the free parameters to optimize. The objective function f to minimize was the root of the integral of the squared difference of the dose in the target volume and a reference dose. For the problem, two local minima exist. Therefore, as a secondary criteria, the magnitude of hot and cold spots were taken into account. As a result, the solution with a larger segment width was recommended. From plane to plane for varying radii of PTV and OAR and for different gaps between them, different sets of weights and widths were optimal. Because only one weight for one segment shall be used for all planes (respectively leaf pairs), a strategy for complex three-dimensional (3-D) cases was established to choose a global weight. In a second step, a suitable segment width was chosen, minimizing f for this global weight. The concept was demonstrated in a planning study for a cylindrically symmetric example with a large range of different radii of an OAR along the patient axis. The method is discussed for some classes of tumor/organ at risk combinations. Noncylindrically symmetric cases were treated exemplarily. The product of width and weight of

  5. Method and apparatus for logging short radius horizontal drainholes

    SciTech Connect

    Taylor, D.E.

    1991-04-30

    This patent describes an apparatus for use in logging a short radius horizontal drainhole. It comprises: a tubing string having a low portion; the lower portion of the tubing string including sensor support means therein; the lower portion of the tubing string containing openings communicating with the interior thereof in the vicinity of the sensor support means to thereby exposed the interior to the pressure and temperature conditions of the horizontal drainhole; and the lower portion of the tubing string including an end portion extending transversely of the tubing sting.

  6. Kinetic modelling of nitrogen and organics removal in vertical and horizontal flow wetlands.

    PubMed

    Saeed, Tanveer; Sun, Guangzhi

    2011-05-01

    This paper provides a comparative evaluation of the kinetic models that were developed to describe the biodegradation of nitrogen and organics removal in wetland systems. Reaction kinetics that were considered in the model development included first order kinetics, Monod and multiple Monod kinetics; these kinetics were combined with continuous-stirred tank reactor (CSTR) or plug flow pattern to produce equations to link inlet and outlet concentrations of each key pollutants across a single wetland. Using three statistical parameters, a critical evaluation of five potential models was made for vertical and horizontal flow wetlands. The results recommended the models that were developed based on Monod models, for predicting the removal of nitrogen and organics in a vertical and horizontal flow wetland system. No clear correlation was observed between influent BOD/COD values and kinetic coefficients of BOD(5) in VF and HF wetlands, illustrating that the removal of biodegradable organics was insensitive to the nature of organic matter. Higher effluent COD/TN values coincided with greater denitrification kinetic coefficients, signifying the dependency of denitrification on the availability of COD in VF wetland systems. In contrast, the trend was opposite in HF wetlands, indicating that availability of NO(3)-N was the main limiting step for nitrogen removal. Overall, the results suggested the possible application of the developed alternative predictive models, for understanding the complex biodegradation routes of nitrogen and organics removal in VF and HF wetland systems.

  7. Experimental study of stability and transients in a horizontally heated boiling helium thermosyphon

    NASA Astrophysics Data System (ADS)

    Furci, H.; Four, A.; Baudouy, B.

    2015-12-01

    Experiments were conducted on a liquid helium natural circulation loop with a 4 m long horizontal heated section. Wall temperatures on the heated section, mass flow rate and pressure drop were measured in steady and transient regimes. The stability of the loop has been studied and the power stability limits have been found. Also, different heating configurations were explored and their drawbacks and benefits were observed. The result is that the loop is stable only above a non-zero low power and below a certain upper power limit. The distance from the heating to the vertical riser affects the stability range. It has been found that instabilities at low power or transients following a low power step pulse can produce considerable temperature oscillations, potentially dangerous from the magnet protection point of view.

  8. Non-Uniform Dose Mapping Controlled by Modulated Vertical and Horizontal Scans

    SciTech Connect

    Ninomiya, S.; Kimura, Y.; Kudo, T.; Ochi, A.; Toda, R.; Tsukihara, M.; Sato, F.; Fuse, G.; Ueno, K.; Sugitani, M.

    2008-11-03

    Since geometries of semi-conductor devices continue to shrink, the requirement for each process becomes severer to keep uniformity of electrical parameters of the semi-conductor devices. A larger wafer also causes larger variations. Thus it has been strongly required for ion implantation process to compensate for the variations from other processes because of its good dose controllability. A newly developed mapping of intentional non-uniform dosage system, which is named 'MIND system', is implemented in SEN's single-wafer-type implanters. The MIND system controls both horizontal and vertical scan speed simultaneously. Intentional two-dimensional non-uniform profiles of sheet resistance, such as concentric and eccentric profiles, are obtained only by single-step ion implantation.

  9. Meissner-Effect Stepping Motor

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1991-01-01

    Proposed stepping motor derives torque from diamagnetic repulsion produced by Meissner effect - exclusion of magnetic field from interior of superconductor. Design of motor takes advantage of silver-doped YB2Cu3O and other compounds superconductive at temperatures as high as that of liquid nitrogen. Skin of rotor cooled below its superconducting-transition temperature by liquid nitrogen. O-rings prevent leaks of liquid nitrogen from rotor. Weight, cost, and maintenance reduced.

  10. Segmented Coil Fails In Steps

    NASA Technical Reports Server (NTRS)

    Stedman, Ronald S.

    1990-01-01

    Electromagnetic coil degrades in steps when faults occur, continues to operate at reduced level instead of failing catastrophically. Made in segments connected in series and separated by electrically insulating barriers. Fault does not damage adjacent components or create hazard. Used to control valves in such critical applications as cooling systems of power generators and chemical process equipment, where flammable liquids or gases handled. Also adapts to electrical control of motors.

  11. Stepped frequency ground penetrating radar

    DOEpatents

    Vadnais, Kenneth G.; Bashforth, Michael B.; Lewallen, Tricia S.; Nammath, Sharyn R.

    1994-01-01

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  12. An irradiation facility with a horizontal beam for radiobiological studies.

    PubMed

    Czub, J; Banas, D; Braziewicz, J; Choinski, J; Jaskóla, M; Korman, A; Szeflinski, Z; Wójcik, A

    2006-01-01

    A facility with a horizontal beam for radiobiological experiments with heavy ions has been designed and constructed at the Heavy Ion Laboratory in Warsaw University. The facility is optimal to investigate the radiobiological effects of charged heavy particles on a cellular or molecular level as in the region of the Bragg peak.

  13. 8. VIEW SOUTH OF PRIMARY REDUCING GEARS; HORIZONTAL ARM AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW SOUTH OF PRIMARY REDUCING GEARS; HORIZONTAL ARM AT CENTER OF PHOTOGRAPH IS A PART OF LEVER MECHANISM THAT LOCKS MECHANICAL BRAKE; 75 LB. COUNTERWEIGHT IS AT EXTREME LEFT CENTER - East Washington Avenue Bridge, Spanning Pequonnock River at East Washington Avenue, Bridgeport, Fairfield County, CT

  14. Physiology and Impact of Horizontal Connections in Rat Neocortex.

    PubMed

    Schnepel, Philipp; Kumar, Arvind; Zohar, Mihael; Aertsen, Ad; Boucsein, Clemens

    2015-10-01

    Cortical information processing at the cellular level has predominantly been studied in local networks, which are dominated by strong vertical connectivity between layers. However, recent studies suggest that the bulk of axons targeting pyramidal neurons most likely originate from outside this local range, emphasizing the importance of horizontal connections. We mapped a subset of these connections to L5B pyramidal neurons in rat somatosensory cortex with photostimulation, identifying intact projections up to a lateral distance of 2 mm. Our estimates of the spatial distribution of cells presynaptic to L5B pyramids support the idea that the majority is located outside the local volume. The synaptic physiology of horizontal connections does not differ markedly from that of local connections, whereas the layer and cell-type-dependent pattern of innervation does. Apart from L2/3, L6A provides a strong source of horizontal connections. Implementing our data into a spiking neuronal network model shows that more horizontal connections promote robust asynchronous ongoing activity states and reduce noise correlations in stimulus-induced activity.

  15. Horizontal and Vertical Attentional Orienting in Parkinson's Disease

    ERIC Educational Resources Information Center

    Nys, Gudrun M. S.; Santens, Patrick; Vingerhoets, Guy

    2010-01-01

    Patients with Parkinson's disease (PD) typically suffer from an asymmetric degeneration of dopaminergic cells in the substantia nigra, resulting in right-sided (RPD) or left-sided (LPD) predominance of motor symptomatology. As the dopaminergic system is also involved in attention, we examined horizontal and vertical orienting of attention in LPD…

  16. 48. View of typical 90 degree elbow located at horizontal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. View of typical 90 degree elbow located at horizontal corner with output (to scanner radar system control switch) waveguide on top and return wave on bottom of photograph. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  17. Slim-hole horizontal well improves gas storage field deliverability

    SciTech Connect

    Gredell, M.E.; Benson, M.A.

    1995-12-11

    A slim-hole horizontal well in a gas storage field, drilled with a 2,000-ft lateral section under a city, initially produced about four times more than a nearby offset vertical well. The ability of the well to cycle gas efficiently from the area under the city will be determined by monitoring the future performance of the well and field. The objectives and conditions of this project were ideal for a slim-hole horizontal well, and the results suggest the potential for more horizontal slim-hole wells in other gas storage applications. The slim-hole well design helped lower total costs. Among the technical and operational issues addressed on this horizontal well project were prediction of well performance and benefits, environmental and safety concerns of drilling in an urban area, optimizing well design parameters, protecting the integrity of the storage zone, and geosteering in a thin reservoir. The paper describes the reservoir, field development, feasibility studies, well location, well plan, radius, the lateral section, well completion, and results.

  18. DETAIL OF THE TRIPLEGANGED WINDOWS WITH HORIZONTAL LIGHTS AT THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THE TRIPLE-GANGED WINDOWS WITH HORIZONTAL LIGHTS AT THE END OF THE SECOND STORY PORTION OF THE SOUTHWEST WING. VIEW FACING NORTH - U.S. Naval Base, Pearl Harbor, Bloch Recreation Center & Arena, Between Center Drive & North Road near Nimitz Gate, Pearl City, Honolulu County, HI

  19. 77. Detail view looking east showing Dovel horizontal gas washer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    77. Detail view looking east showing Dovel horizontal gas washer in foreground, Rust Co. boilers and blowing engine house at left, and Babcock & Wilcox type boilers at right. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  20. Detail of 25' highband reflector screen pole showing the horizontal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of 25' high-band reflector screen pole showing the horizontal wood beams and vertical wires hung from ceramic insulators, note the dipole antenna element and 94' low-band reflector screen poles in background, view facing north - U.S. Naval Base, Pearl Harbor, Naval Radio Station, AF/FRD-10 Circularly Disposed Antenna Array, Wahiawa, Honolulu County, HI

  1. On lifting line analysis of horizontal axis windturbines

    NASA Astrophysics Data System (ADS)

    Politis, G. K.; Loukakis, T. A.

    A convergent iteration scheme for lifting line performance analysis of horizontal axis windturbines is presented. Lifting line correction factors are introduced and compared with those of Prandtl and Goldstein. Lifting line and strip theory formulations are applied for the calculation of performance for two windturbines. Differences of engineering importance are shown to exist in the prediction of the Power coefficient.

  2. 10. VIEW EAST, RECESS AREA WITH BOTTOM HORIZONTAL BEAM FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW EAST, RECESS AREA WITH BOTTOM HORIZONTAL BEAM FOR EAST GATE - Bald Eagle Cross-Cut Canal Lock, North of Water Street along West Branch of Susquehanna River South bank, 500 feet East of Jay Street Bridge, Lock Haven, Clinton County, PA

  3. EXAMINATION OF MODEL PREDICTIONS AT DIFFERENT HORIZONTAL GRID RESOLUTIONS

    EPA Science Inventory

    While fluctuations in meteorological and air quality variables occur on a continuum of spatial scales, the horizontal grid spacing of coupled meteorological and photochemical models sets a lower limit on the spatial scales that they can resolve. However, both computational costs ...

  4. Modified horizontal solar collector for low temperature grain drying

    SciTech Connect

    1980-01-27

    The project consisted of constructing a horizontal solar collector with a small amount of rock storage integrated into the collector air stream. The collected energy was used to dry corn in a 6000 bushel low-temperature drying facility. The collector proved to be economically feasible to build and collected sufficient energy to show a reasonable return on the investment.

  5. HORIZONTAL CONFIGURATION OF THE LASAGNA (TM) TREATMENT TECHNOLOGY USER GUIDE

    EPA Science Inventory

    This report is a user's guide that discusses the technology and operations unique to the installation and operation of the horizontal configuration of the Lasagna? integrated soil remediation technology. This technology, called Lasagna? because of the layers of electrodes and tr...

  6. Language Training for Enhanced Horizontal Communication: A Challenge for MNCs.

    ERIC Educational Resources Information Center

    Charles, Mirjaliisa; Marschan-Piekkari, Rebecca

    2002-01-01

    Identifies and examines the problems that staff in multinational corporations (MNCs) experience in horizontal communication with other units and discusses the implications of these problems for in-company language training. Concludes that illustrative interview data suggests that corporate training schemes should focus on the broad spectrum of…

  7. Global Analysis of Horizontal Gene Transfer in Fusarium verticillioides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The co-occurrence of microbes within plants and other specialized niches may facilitate horizontal gene transfer (HGT) affecting host-pathogen interactions. We recently identified fungal-to-fungal HGTs involving metabolic gene clusters. For a global analysis of HGTs in the maize pathogen Fusarium ve...

  8. PERSPECTIVE WITH WEST PORTAL. THE BRIDGE IS CLAD IN HORIZONTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE WITH WEST PORTAL. THE BRIDGE IS CLAD IN HORIZONTAL CLAPBOARD SIDING AND HAS A SHEET METAL ROOF. NOTE THE TWO OPENINGS THAT RUN THE LENGTH OF THE BRIDGE; ONE IS AT THE EAVES AND THE OTHER IS ABOUT 4’ ABOVE THE DECK. - Dreibelbis Station Bridge, Spanning Maiden Creek, Balthaser Road (TR 745), Lenhartsville, Berks County, PA

  9. Completion techniques for horizontal wells in the Pearsall Austin Chalk

    SciTech Connect

    Pope, C.D.; Handren, P.J. )

    1992-05-01

    Oryx Energy Co. used three basic completion techniques and various combinations of them to complete 20 horizontal wells in the Pearsall Austin Chalk. The completion method selected is based on a general set of guidelines. In this paper additionally, equipment selection and various types of workover operations are reviewed.

  10. 5. VIEW, LOOKING WEST BENEATH BRIDGE, SHOWING GIRDER FRAMEWORK, HORIZONTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW, LOOKING WEST BENEATH BRIDGE, SHOWING GIRDER FRAMEWORK, HORIZONTAL LATERAL DIAGONAL TENSION EYEBARS, PAIRS OF EYEBARS RUNNING THE LENGTH OF THE BRIDGE, AND RUNNING SURFACE RAILROAD TIES - Heber Creeper Railroad Line, Olmstead Bridge, Spanning Provo River, Provo, Utah County, UT

  11. Modeling the impact of spatial relationships on horizontal curve safety.

    PubMed

    Findley, Daniel J; Hummer, Joseph E; Rasdorf, William; Zegeer, Charles V; Fowler, Tyler J

    2012-03-01

    The curved segments of roadways are more hazardous because of the additional centripetalforces exerted on a vehicle, driver expectations, and other factors. The safety of a curve is dependent on various factors, most notably by geometric factors, but the location of a curve in relation to other curves is also thought to influence the safety of those curves because of a driver's expectation to encounter additional curves. The link between an individual curve's geometric characteristics and its safety performance has been established, but spatial considerations are typically not included in a safety analysis. The spatial considerations included in this research consisted of four components: distance to adjacent curves, direction of turn of the adjacent curves, and radius and length of the adjacent curves. The primary objective of this paper is to quantify the spatial relationship between adjacent horizontal curves and horizontal curve safety using a crash modification factor. Doing so enables a safety professional to more accurately estimate safety to allocate funding to reduce or prevent future collisions and more efficiently design new roadway sections to minimize crash risk where there will be a series of curves along a route. The most important finding from this research is the statistical significance of spatial considerations for the prediction of horizontal curve safety. The distances to adjacent curves were found to be a reliable predictor of observed collisions. This research recommends a model which utilizes spatial considerations for horizontal curve safety prediction in addition to current Highway Safety Manual prediction capabilities using individual curve geometric features.

  12. Horizontal wells improve recovery at the Elk Hills Petroleum Reserve

    SciTech Connect

    Rintoul, B.

    1995-11-01

    In 1988 the US Department of Energy and Bechtel implemented a program to slow production declines in the Elk Hills 26R pool sand of the Naval Petroleum Reserve No. 1. It was also hoped horizontal wells would increase the production rate, decrease gas production and extend economic life of the reservoir. The Stevens sand pool targeted for the project is a high-quality, sand-rich turbidite channel system encapsulated within Miocene Monterey siliceous shales, mudstones and associated sediments. The pool is about 3-miles long by 3/4-mile wide. The paper describes the specifications and drilling of the first four out of the 14 horizontal wells drilled at this facility. Horizontal drilling technology has completely altered the future of the 26R pool. In 1980 estimated ultimate recovery (EUR) from the sand was 211 million bbl. With the latest horizontal well drilling campaign, the pool is expected to pass that estimate in 1997 when oil production is forecasted to be at least 13,000 b/d. EUR form the 26R sand now is more than 250 million bbl, and even that estimate is being revised upward.

  13. Improved oil recovery using horizontal wells at Elk Hills, California

    SciTech Connect

    Gangle, F.J.; Schultz, K.L.; McJannet, G.S.; Ezekwe, N.

    1995-03-01

    Eight horizontal wells have been drilled and completed in a steeply dipping Stevens sand reservoir in the Elk Hills field, Kern County, California. The subject reservoir, called the Stevens 26R, is a turbidite channel sand deposit one mile wide, three miles long, and one mile deep. Formation beds have a gross thickness up to 1,500 feet and dips as high as 60 degrees on the flanks. The original oil column of 1,810 feet has been pulled down to 200 feet by continual production since 1976. The reservoir management operating strategy has been full pressure maintenance by crestal gas injection since 1976. The steep dip of the formation makes gravity drainage the dominant drive mechanism. Additionally, improved recovery is coming from cycling dry gas through the large secondary gas cap region. The prudent placement of the horizontal wells above the oil/water contact promises to improve oil recovery and extend the operating life of the reservoir. Field results are given to compare the performance of the horizontal wells with the conventional wells. The horizontal wells produce at higher rates, lower draw downs, and lower gas/oil ratio which will extend the life of the project and result in higher recovery.

  14. Evolution of and horizontal gene transfer in the Endornavirus genus.

    PubMed

    Song, Dami; Cho, Won Kyong; Park, Sang-Ho; Jo, Yeonhwa; Kim, Kook-Hyung

    2013-01-01

    The transfer of genetic information between unrelated species is referred to as horizontal gene transfer. Previous studies have demonstrated that both retroviral and non-retroviral sequences have been integrated into eukaryotic genomes. Recently, we identified many non-retroviral sequences in plant genomes. In this study, we investigated the evolutionary origin and gene transfer of domains present in endornaviruses which are double-stranded RNA viruses. Using the available sequences for endornaviruses, we found that Bell pepper endornavirus-like sequences homologous to the glycosyltransferase 28 domain are present in plants, fungi, and bacteria. The phylogenetic analysis revealed the glycosyltransferase 28 domain of Bell pepper endornavirus may have originated from bacteria. In addition, two domains of Oryza sativa endornavirus, a glycosyltransferase sugar-binding domain and a capsular polysaccharide synthesis protein, also exhibited high similarity to those of bacteria. We found evidence that at least four independent horizontal gene transfer events for the glycosyltransferase 28 domain have occurred among plants, fungi, and bacteria. The glycosyltransferase sugar-binding domains of two proteobacteria may have been horizontally transferred to the genome of Thalassiosira pseudonana. Our study is the first to show that three glycome-related viral genes in the genus Endornavirus have been acquired from marine bacteria by horizontal gene transfer.

  15. Widespread horizontal transfer of mitochondrial genes in flowering plants.

    PubMed

    Bergthorsson, Ulfar; Adams, Keith L; Thomason, Brendan; Palmer, Jeffrey D

    2003-07-10

    Horizontal gene transfer--the exchange of genes across mating barriers--is recognized as a major force in bacterial evolution. However, in eukaryotes it is prevalent only in certain phagotrophic protists and limited largely to the ancient acquisition of bacterial genes. Although the human genome was initially reported to contain over 100 genes acquired during vertebrate evolution from bacteria, this claim was immediately and repeatedly rebutted. Moreover, horizontal transfer is unknown within the evolution of animals, plants and fungi except in the special context of mobile genetic elements. Here we show, however, that standard mitochondrial genes, encoding ribosomal and respiratory proteins, are subject to evolutionarily frequent horizontal transfer between distantly related flowering plants. These transfers have created a variety of genomic outcomes, including gene duplication, recapture of genes lost through transfer to the nucleus, and chimaeric, half-monocot, half-dicot genes. These results imply the existence of mechanisms for the delivery of DNA between unrelated plants, indicate that horizontal transfer is also a force in plant nuclear genomes, and are discussed in the contexts of plant molecular phylogeny and genetically modified plants.

  16. The effect of tip shields on a horizontal tail surface

    NASA Technical Reports Server (NTRS)

    Dronin, Paul V; Ramsden, Earl I; Higgins, George J

    1928-01-01

    A series of experiments made in the wind tunnel of the Daniel Guggenheim School of Aeronautics, New York University, on the effect of tip shields on a horizontal tail surface are described and discussed. It was found that some aerodynamic gain can be obtained by the use of tip shields though it is considered doubtful whether their use would be practical.

  17. Coking oven with horizontal chambers for producing coke

    SciTech Connect

    Jakobi, W.

    1984-06-26

    In a coking oven with a horizontal chamber the chamber is provided with a filling hole having a cylindrical portion with the diameter D and a reduced portion downwardly extending therefrom into the chamber over the height H. The ratio between D and H 1.5.

  18. Survey of Unsteady Computational Aerodynamics for Horizontal Axis Wind Turbines

    NASA Astrophysics Data System (ADS)

    Frunzulicǎ, F.; Dumitrescu, H.; Cardoş, V.

    2010-09-01

    We present a short review of aerodynamic computational models for horizontal axis wind turbines (HAWT). Models presented have a various level of complexity to calculate aerodynamic loads on rotor of HAWT, starting with the simplest blade element momentum (BEM) and ending with the complex model of Navier-Stokes equations. Also, we present some computational aspects of these models.

  19. General view in the Horizontal Processing Area of the Space ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view in the Horizontal Processing Area of the Space Shuttle Main Engine (SSME) Processing Facility at Kennedy Space Center. This view is looking at SSME 2052 and 2051 mounted on their SSME Engine Handlers. - Space Transportation System, Space Shuttle Main Engine, Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  20. General view in the Horizontal Processing Area of the Space ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view in the Horizontal Processing Area of the Space Shuttle Main Engine (SSME) Processing Facility at Kennedy Space Center. This view is looking at SSME number 2048 mounted on an SSME engine Handler. - Space Transportation System, Space Shuttle Main Engine, Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  1. Burst of ethylene upon horizontal placement of tomato seedlings

    NASA Technical Reports Server (NTRS)

    Harrison, M.; Pickard, B. G.

    1984-01-01

    Seedlings of Lycopersicon esculentum Mill. cv Rutgers emit a pulse of ethylene during the first 2 to 4 minutes following horizontal placement. Because this burst appears too rapid and brief to be mediated by increase in net activity of 1-aminocyclopropane-1-carboxylic acid synthase, it might result form accelerated transformation of vacuolar 1-aminocyclopropane-1-carboxylic acid to ethylene.

  2. ALCAR - A Model for Horizontal R&D Consortia

    SciTech Connect

    Barthold, G.B.; Das, S.K.; Hayden, H.W.

    1999-03-01

    The ALCARTM Consortium was created to develop a low cost, non-heat treatable automotive body sheet alloy. This paper will discuss the management aspects of organizing and running a horizontal consortium for competing companies to cooperate in conducting pre-competitive research and development involving the US Department of Energy, National Laboratories, Universities and industrial consultants.

  3. Evolution of and horizontal gene transfer in the Endornavirus genus.

    PubMed

    Song, Dami; Cho, Won Kyong; Park, Sang-Ho; Jo, Yeonhwa; Kim, Kook-Hyung

    2013-01-01

    The transfer of genetic information between unrelated species is referred to as horizontal gene transfer. Previous studies have demonstrated that both retroviral and non-retroviral sequences have been integrated into eukaryotic genomes. Recently, we identified many non-retroviral sequences in plant genomes. In this study, we investigated the evolutionary origin and gene transfer of domains present in endornaviruses which are double-stranded RNA viruses. Using the available sequences for endornaviruses, we found that Bell pepper endornavirus-like sequences homologous to the glycosyltransferase 28 domain are present in plants, fungi, and bacteria. The phylogenetic analysis revealed the glycosyltransferase 28 domain of Bell pepper endornavirus may have originated from bacteria. In addition, two domains of Oryza sativa endornavirus, a glycosyltransferase sugar-binding domain and a capsular polysaccharide synthesis protein, also exhibited high similarity to those of bacteria. We found evidence that at least four independent horizontal gene transfer events for the glycosyltransferase 28 domain have occurred among plants, fungi, and bacteria. The glycosyltransferase sugar-binding domains of two proteobacteria may have been horizontally transferred to the genome of Thalassiosira pseudonana. Our study is the first to show that three glycome-related viral genes in the genus Endornavirus have been acquired from marine bacteria by horizontal gene transfer. PMID:23667703

  4. Horizontal well application in QGPC - Qatar, Arabian Gulf

    SciTech Connect

    Jubralla, A.F.; Al-Omran, J.; Al-Omran, S.

    1995-08-01

    As with many other areas in the world, the application of horizontal well technology in Qatar has changed the {open_quotes}old time{close_quotes} reservoir development philosophy and approach. QGPC`s first experience with this technology was for increased injectivity in an upper Jurassic reservoir which is comprised by alternating high and low permeable layers. The first well drilled in 1990 offshore was an extreme success and the application was justified for fieldwide implementation. Huge costs were saved as a result. This was followed by 2 horizontal wells for increased productivity in a typically tight (< 5 mD) chalky limestone of Cretaceous age. A fourth offshore well drilled in a thin (30 ft) and tight (10-100 mD) Jurassic dolomite overlaying a stack of relatively thick (25-70 ft) and {open_quotes}Watered Out{close_quotes} grain and grain-packstones, (500-4500 mD) indicated another viable and successful application. A similar approach in the Onshore Dukhan field has been adopted for another Upper Jurassic reservoir. The reservoir is 80 ft thick and is being developed by vertical wells. However, permeability contrast between the upper and lower cycles had caused preferential production and hence injection across the lower cycles, leaving the upper cycles effectively undrained. Horizontal wells have resulted in productivity and injectivity improvements by a factor 3 to 5 that of vertical wells. Therefore a field wide development scheme is being implemented. 3D seismic and the imaging tools, such as the FMS, reconciled with horizontal cores have assisted in understanding the lateral variation and the macro and micro architectural and structural details of these reservoirs. Such tools are essential for the optimum design of horizontal wells.

  5. Horizontal drilling the Bakken Formation, Williston basin: A new approach

    SciTech Connect

    Lefever, J.A. )

    1990-05-01

    Horizontal drilling is an attractive new approach to exploration and development of the Mississippian/Devonian Bakken Formation in the southwestern part of North Dakota. This drilling technique increases the probability of success, the profit potential, the effective drainage area maximizing recoverable reserves, and the productivity by encountering more natural occurring fractures. The target formation, the Mississippian/Devonian Bakken, consists of three members in an overlapping relationship, a lower organic-rich black shale, a middle siltstone/limestone, and an upper organic-rich black shale. It attains a maximum thickness of 145 ft and thins to a feather edge along its depositional limit. Considered to be a major source rock for the Williston basin, the Bakken is usually overpressured where productive. Overpressuring is attributed to intense hydrocarbon generation. Reservoir properties are poor with core fluid porosities being generally 5% or less and permeabilities ranging from 0.1 to 0.2 md. The presence of natural fractures in the shale are necessary for production. Two types of fractures are associated with Bakken reservoirs: large vertical fractures (of tectonic origin) and microfractures (probably related to hydrocarbon generation). An economic comparison between horizontal and vertical wells show that well completion costs are approximately two times higher (average costs; $1,500,000 for a horizontal to $850,000 for a vertical) with average payout for horizontal wells projected to occur in half the time (1.5 yr instead of 3.4 yr). Projected production and reserves are considered to be 2 to 4 times greater from a horizontal well.

  6. Measuring the vertical permeability of horizontally- stratified sedimentary rocks

    SciTech Connect

    Novakowski, K.S.; Lapcevic, P.A. ); Reichart, T.M. )

    1993-03-01

    The vertical permeability of horizontally stratified rocks is usually assumed to be significantly less than the permeability of horizontal structural features such as bedding plane partings and sheeting structure. Consequently it is also assumed that this type of media provides suitable vertical barriers to the migration of both aqueous and non-aqueous phase groundwater contaminants. To investigate this assumption, a site adjacent to an inactive dolostone quarry was instrumented using nine boreholes drilled to a depth of approximately 25 m in a 30 x 30 m area. The area is immediately underlain by flat-lying thick-bedded dolostones of Middle-Silurian age. Six of the boreholes were drilled at angle of 45[degree] to intersect two vertical fracture sets oriented at 020[degree] and 110[degree] which were identified by mapping the fractures in the quarry. Detailed hydraulic tests (constant-head method) were conducted in each of the boreholes using a packer spacing of 0.5 m to determine the hydraulic properties of the individual horizontal and vertical fractures and fracture zones. In addition, four pumping tests were conducted in which a fracture zone in one of the vertical boreholes was shut-in and pumped and the hydraulic response was monitored in the observation boreholes using pressure transducer installed in 15 intervals isolated with multiple-packer strings. The results of the constant-head tests show that although the groundwater flow system in the dolostone is dominated by 3--4 horizontal fracture zones, the average permeability of the vertical fractures is only one order of magnitude less than the average permeability of the horizontal fractures. However, this aspect of the flow system is not detected using pumping tests, the results of which suggest that the average permeability is 3--4 orders of magnitude less in the vertical direction.

  7. [Effect of horizontal rotary culture on zebrafish vascular development].

    PubMed

    Sun, Ting; Xie, Xiang; Zhang, Jian-Qing; Bao, Jing; Tang, Chuan-Zheng; Lei, Dao-Xi; Qiu, Ju-Hui; Wang, Gui-Xue

    2013-04-01

    With the development of space life science, a study on the influence of microgravity on organism has been an increasingly concerned topic. Lots of studies indicate that microgravity plays an important role in the early development of embryos. The vascular system as the first-function system of embryos provides an interesting topic for many researchers. However, those studies were mostly carried out in vitro by rotary cell culture system (RCCS), while few experiments were done in vivo. Using zebrafish as a model, this research investigated the effects of horizontal rotary culture on the vascular development in vivo. Zebrafish embryos at 24 hpf (hour post-fertilization) were selected and divided into two groups. One group was cultured by the shaker, and the other was cultured normally as the control. After 12 h, all the embryos were collected and detected. The phenotype of zebrafish was observed by stereo microscope. Then, the expression of vascular specific expression factor, flk1, flt4, and ephrinB2 was compared by RT-PCR, qPCR, and in situ hybridization, respectively. Cell apoptosis and proliferation in situ were observed using TUNEL assay and bromodeoxyuridine incorporation. The results demonstrated that horizontal rotary culture at 90 r/min decreased the hatching of embryos (10.3±0.41 vs. 0.0, P<0.05), accelerate the heart rate (223.5±2.32 vs. 185.0±3.23, P<0.05) and increased the content of melanin in zebrafish significantly. At the same time, we found some differences in the vascular system of zebrafish after horizontal rotary culture which caused a down regulation of flk1, flt4, and ephrinB2. On the other hand, horizontal rotary culture accelerated the apoptosis of cells in zebrafish, but showed no significance in proliferation. In conclusion, horizontal rotary culture has a significant influence on the vascular development in zebrafish. PMID:23659941

  8. Auditory spatial resolution in horizontal, vertical, and diagonal planes.

    PubMed

    Grantham, D Wesley; Hornsby, Benjamin W Y; Erpenbeck, Eric A

    2003-08-01

    Minimum audible angle (MAA) and minimum audible movement angle (MAMA) thresholds were measured for stimuli in horizontal, vertical, and diagonal (60 degrees) planes. A pseudovirtual technique was employed in which signals were recorded through KEMAR's ears and played back to subjects through insert earphones. Thresholds were obtained for wideband, high-pass, and low-pass noises. Only 6 of 20 subjects obtained wideband vertical-plane MAAs less than 10 degrees, and only these 6 subjects were retained for the complete study. For all three filter conditions thresholds were lowest in the horizontal plane, slightly (but significantly) higher in the diagonal plane, and highest for the vertical plane. These results were similar in magnitude and pattern to those reported by Perrott and Saberi [J. Acoust. Soc. Am. 87, 1728-1731 (1990)] and Saberi and Perrott [J. Acoust. Soc. Am. 88, 2639-2644 (1990)], except that these investigators generally found that thresholds for diagonal planes were as good as those for the horizontal plane. The present results are consistent with the hypothesis that diagonal-plane performance is based on independent contributions from a horizontal-plane system (sensitive to interaural differences) and a vertical-plane system (sensitive to pinna-based spectral changes). Measurements of the stimuli recorded through KEMAR indicated that sources presented from diagonal planes can produce larger interaural level differences (ILDs) in certain frequency regions than would be expected based on the horizontal projection of the trajectory. Such frequency-specific ILD cues may underlie the very good performance reported in previous studies for diagonal spatial resolution. Subjects in the present study could apparently not take advantage of these cues in the diagonal-plane condition, possibly because they did not externalize the images to their appropriate positions in space or possibly because of the absence of a patterned visual field.

  9. Acta Clinica Croatica: progress of a journal step by step.

    PubMed

    Ramljak, Gordana

    2014-03-01

    The journal Acta Clinica Croatica (ACC) was founded in 1962 under the title Anali Bolnice Dr. M. Stojanović. In 1995, the title of the journal was changed into its present form and ever since all papers have been published in English. In 2000, the electronic (online) edition of the ACC was released in addition to the print version. The paper presents development of the journal from 1962 to 2012 based on the analysis of the following SCOPUS citation index parameters: type and number of documents published in the journal; number of citations; and number of domestic and foreign authors. The studied period was analyzed in three time segments: the period from 1995 to 1999, the period from 2000 to 2006 and the period from 2007 to 2012. The same parameters were analyzed in the Web of Science/SCI-Expanded bibliographic and citation index for the 2007-2012 period. The increasing number of documents, authors (both domestic and foreign) and citations demonstrates gradual rise in the quality, visibility and impact of the journal. The fifty years of experience show that a goal, at first very distant and almost unachievable, may be reached by progressing step by step.

  10. An evaluation of dimensional accuracy of one-step and two-step impression technique using addition silicone impression material: an in vitro study.

    PubMed

    Pande, Neelam A; Parkhedkar, R D

    2013-09-01

    The study is aimed to evaluate the dimensional accuracy, the effect of undercut of two different configurations and the elastic recovery of addition silicone impression material assessed indirectly, by measuring the dimensions on stone models recorded from the impression of the master model, using one-step and two-step impression technique, for addition silicone impression materials. Measurements are taken to evaluate horizontal or linear and vertical dimensional changes, of the abutment V and abutment C from the stainless steel model. Heavy body/light body material is used for making one-step impression technique in a custom tray. Putty/light body is used for taking two-step technique in a stock metal tray. Improved die stone is used for pouring the impression. The different 11 locations on the dies produced by two different techniques are measured microscopically on image analyzer and compared with those of stainless steel model. Anova test was applied to test the differences of mean values of inter and intra abutment measurements, to calculate p value. Unpaired t test was applied to calculate t value. Results showed less deviation of stone models produced by one-step technique from stainless steel model, whereas the deviation of stone models produced by two-step is comparatively more. (p < 0.01). This difference of deviation is significantly less in one-step as compared to two-step technique. One-step is sufficiently dimensionally accurate than two-step technique in conjunction with addition silicone impression material. They have the best elastic recovery from the two undercut configurations.

  11. Completion Design Considerations for a Horizontal Enhanced Geothermal System

    SciTech Connect

    Olson, Jeffrey; Eustes, Alfred; Fleckenstein, William; Eker, Erdinc; Baker, Reed; Augustine, Chad

    2015-09-02

    The petroleum industry has had considerable success in recent decades in developing unconventional shale plays using horizontal drilling and multi-zonal isolation and stimulation techniques to fracture tight formations to enable the commercial production of oil and gas. Similar well completions could be used in Enhanced Geothermal Systems (EGS) to create multiple fractures from horizontal wells. This study assesses whether well completion techniques used in the unconventional shale industry to create multi-stage fractures can be applied to an enhanced geothermal system, with a focus on the completion of the EGS injection well. This study assumes an Enhanced Geothermal System (EGS) consisting of a central horizontal injection well flanked on each side by horizontal production wells, connected to the injection well by multiple fractures. The focus is on the design and completion of the horizontal well. For the purpose of developing design criteria, a reservoir temperature of 200 degrees C (392 degrees F) and an injection well flow rate of 87,000 barrels per day (160 kg/s), corresponding to production well flow rates of 43,500 barrels per day (80 kg/s) is assumed. The analysis found that 9-5/8 inches 53.5 pounds per foot (ppf) P110 casing string with premium connections meets all design criteria for the horizontal section of injection well. A P110 grade is fairly common and is often used in horizontal sections of shale development wells in petroleum operations. Next, several zonal isolation systems commonly used in the shale gas industry were evaluated. Three techniques were evaluated -- a 'plug and perf' design, a 'sand and perf' design, and a 'packer and port' design. A plug and perf system utilizes a cemented casing throughout the length of the injector wellbore. The sand and perf system is identical to the plug and perf system, but replaces packers with sand placed in the casing after stimulation to screen out the stimulated perforated zones and provide zonal

  12. 48 CFR 52.214-25 - Step Two of Two-Step Sealed Bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Step Two of Two-Step... Clauses 52.214-25 Step Two of Two-Step Sealed Bidding. As prescribed in 14.201-6(t), insert the following provision: Step Two of Two-Step Sealed Bidding (APR 1985) (a) This invitation for bids is issued to...

  13. 48 CFR 52.214-25 - Step Two of Two-Step Sealed Bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Step Two of Two-Step... Clauses 52.214-25 Step Two of Two-Step Sealed Bidding. As prescribed in 14.201-6(t), insert the following provision: Step Two of Two-Step Sealed Bidding (APR 1985) (a) This invitation for bids is issued to...

  14. Adsorption on a stepped substrate

    NASA Astrophysics Data System (ADS)

    Merikoski, J.; Timonen, J.; Kaski, K.

    1994-09-01

    The effect of substrate steps on the adsorption of particles is considered. The problem is formulated as a lattice-gas model with nearest neighbor interactions and it is studied by a numerical transfer-matrix method. In particular, the influence of the substrate-induced row potential on adsorbed monolayers is discussed. It is found that strong row-transition-like features appear in the presence of a row potential and it is suggested that these may be seen in adsorption on vicinal faces.

  15. Lessons learned in stepped chute research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early research on stepped chutes focused on steep gravity style stepped chutes. Today, the research trend has shifted to stepped chutes applied to more moderate slopes like those for aging embankment dams. Research contributions have been made on hydraulic properties of stepped chutes including ai...

  16. Hydraulic Design of Stepped Spillways Workshop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped chutes and spillways are commonly used for routing discharges during flood events. In addition, stepped chutes are used for overtopping protection of earthen embankments. Stepped spillways provide significant energy dissipation due to its stepped feature; as a result, the stilling basin as...

  17. Enhanced nitrogen removal in constructed wetlands: effects of dissolved oxygen and step-feeding.

    PubMed

    Li, Fengmin; Lu, Lun; Zheng, Xiang; Ngo, Huu Hao; Liang, Shuang; Guo, Wenshan; Zhang, Xiuwen

    2014-10-01

    Four horizontal subsurface flow constructed wetlands (HSFCWs), named HSFCW1 (three-stage, without step-feeding), HSFCW2 (three-stage, with step-feeding), HSFCW3 (five-stage, without step-feeding) and HSFCW4 (five-stage, with step-feeding) were designed to investigate the effects of dissolved oxygen (DO) and step-feeding on nitrogen removal. High removal of 90.9% COD, 99.1% ammonium nitrogen and 88.1% total nitrogen (TN) were obtained simultaneously in HSFCW4 compared with HSFCW1-3. The excellent TN removal of HSFCW4 was due to artificial aeration provided sufficient DO for nitrification and the favorable anoxic environment created for denitrification. Step-feeding was a crucial factor because it provided sufficient carbon source (high COD: nitrate ratio of 14.3) for the denitrification process. Microbial activities and microbial abundance in HSFCW4 was found to be influenced by DO distribution and step-feeding, and thus improve TN removal. These results suggest that artificial aeration combined with step-feeding could achieve high nitrogen removal in HSFCWs.

  18. Interactions leading to horizontal cell responses in the turtle retina.

    PubMed

    Fuortes, M G; Simon, E J

    1974-07-01

    1. Small responses to large fields of dim monochromatic lights were recorded intracellularly from luminosity horizontal cells (L-cells), chromaticity horizontal cells (C-cells) and cones in the retinae of turtles, Pseudemys scripta elegans.2. Responses of cones to brief flashes applied over steady backgrounds were studied in order to interpret the corresponding responses of horizontal cells. Steady red or green backgrounds make the responses of red-sensitive cones smaller, faster and often diphasic. Green backgrounds have similar effects on the responses of green-sensitive cones to green flashes, but red backgrounds do not change them appreciably. Responses of double cones have properties intermediate between those of red and green cones.3. L-cells of both type I and type II are hyperpolarized by all visible wave-lengths, and their spectral sensitivity in the linear range resembles that of red cones. Their responses are not invariant with respect to colour, and their sensitivity to green relative to red stimuli increases during red backgrounds. These properties suggest that L-cells are activated mainly by red cones but also receive impingement from the red members of double cones.4. Spectral properties of red/green C-cells resemble those of green cones as modified by the recurrent action of L-cells. They can be explained assuming that red/green C-cells receive their principal impingement from green cones and subsidiary interactions from green/blue C-cells and the green members of double comes.5. The spectral sensitivity of the hyperpolarizing responses of green/blue C-cells is ascribed to impingement from blue cones. Their depolarizing responses have complex properties which suggest that they are brought about by the activity of both L-cells (probably through the blue cones) and red/green C-cells.6. It is concluded that the main properties of the responses of the horizontal cells can be explained by a simple circuit in which each horizontal cell is connected to a

  19. What Promotes Wisdom in 12-Step Recovery?

    PubMed

    DiGangi, Julia A; Majer, John M; Mendoza, Leslie; Droege, Jocelyn R; Jason, Leonard A; Contreras, Richard

    2014-01-01

    Research investigations on twelve-step groups such as Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) have addressed a number of resources associated with 12-step recovery. However, little is known about the role of wisdom, and whether aspects of 12-step participation might increase this resource among 12-step members. An exploratory analysis revealed that participants who reported having a "spiritual awakening" and considered themselves "members" of 12-step groups reported significantly higher levels of wisdom. Twelve-step meeting attendance was not significantly related to wisdom scores. Findings suggest certain aspects of 12-step involvement are associated with wisdom and may play a role in substance abuse recovery.

  20. Finite population analysis of the effect of horizontal gene transfer on the origin of an universal and optimal genetic code.

    PubMed

    Aggarwal, Neha; Bandhu, Ashutosh Vishwa; Sengupta, Supratim

    2016-05-27

    The origin of a universal and optimal genetic code remains a compelling mystery in molecular biology and marks an essential step in the origin of DNA and protein based life. We examine a collective evolution model of genetic code origin that allows for unconstrained horizontal transfer of genetic elements within a finite population of sequences each of which is associated with a genetic code selected from a pool of primordial codes. We find that when horizontal transfer of genetic elements is incorporated in this more realistic model of code-sequence coevolution in a finite population, it can increase the likelihood of emergence of a more optimal code eventually leading to its universality through fixation in the population. The establishment of such an optimal code depends on the probability of HGT events. Only when the probability of HGT events is above a critical threshold, we find that the ten amino acid code having a structure that is most consistent with the standard genetic code (SGC) often gets fixed in the population with the highest probability. We examine how the threshold is determined by factors like the population size, length of the sequences and selection coefficient. Our simulation results reveal the conditions under which sharing of coding innovations through horizontal transfer of genetic elements may have facilitated the emergence of a universal code having a structure similar to that of the SGC.

  1. Evaluation of global horizontal irradiance to plane-of-array irradiance models at locations across the United States

    DOE PAGES

    Lave, Matthew; Hayes, William; Pohl, Andrew; Hansen, Clifford W.

    2015-02-02

    We report an evaluation of the accuracy of combinations of models that estimate plane-of-array (POA) irradiance from measured global horizontal irradiance (GHI). This estimation involves two steps: 1) decomposition of GHI into direct and diffuse horizontal components and 2) transposition of direct and diffuse horizontal irradiance (DHI) to POA irradiance. Measured GHI and coincident measured POA irradiance from a variety of climates within the United States were used to evaluate combinations of decomposition and transposition models. A few locations also had DHI measurements, allowing for decoupled analysis of either the decomposition or the transposition models alone. Results suggest that decompositionmore » models had mean bias differences (modeled versus measured) that vary with climate. Transposition model mean bias differences depended more on the model than the location. Lastly, when only GHI measurements were available and combinations of decomposition and transposition models were considered, the smallest mean bias differences were typically found for combinations which included the Hay/Davies transposition model.« less

  2. Finite population analysis of the effect of horizontal gene transfer on the origin of an universal and optimal genetic code

    NASA Astrophysics Data System (ADS)

    Aggarwal, Neha; Vishwa Bandhu, Ashutosh; Sengupta, Supratim

    2016-06-01

    The origin of a universal and optimal genetic code remains a compelling mystery in molecular biology and marks an essential step in the origin of DNA and protein based life. We examine a collective evolution model of genetic code origin that allows for unconstrained horizontal transfer of genetic elements within a finite population of sequences each of which is associated with a genetic code selected from a pool of primordial codes. We find that when horizontal transfer of genetic elements is incorporated in this more realistic model of code-sequence coevolution in a finite population, it can increase the likelihood of emergence of a more optimal code eventually leading to its universality through fixation in the population. The establishment of such an optimal code depends on the probability of HGT events. Only when the probability of HGT events is above a critical threshold, we find that the ten amino acid code having a structure that is most consistent with the standard genetic code (SGC) often gets fixed in the population with the highest probability. We examine how the threshold is determined by factors like the population size, length of the sequences and selection coefficient. Our simulation results reveal the conditions under which sharing of coding innovations through horizontal transfer of genetic elements may have facilitated the emergence of a universal code having a structure similar to that of the SGC.

  3. Horizontal monitoring of soil water content using a novel automated and mobile electromagnetic access-tube sensor

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Zhou, H.; Qin, Y.; Schulze Lammers, P.; Berg, A.; Deng, H.; Cai, X.; Wang, D.; Jones, S. B.

    2014-08-01

    Advances in sensor technology continue to provide new and significant benefits to agriculture. An innovative approach for observing soil water dynamics in the subsurface is introduced using a mobile electromagnetic sensor prototype traveling through a horizontal PVC access tube. A series of tests for evaluating the prototype were designed and conducted to (i) determine the sensor's area of sensitivity (AOS), (ii) measure varied levels of soil water content along the tube and (iii) track temporal changes in soil water content under; (a) two drippers on a horizontal- and (b) multiple drippers on a sloped-soil surface (i.e., 6° slope). The AOS experiment suggested the sensor's fringing field extends to a radius of 5.5 cm from the pipe wall yielding an AOS of 181.3 cm2. Measured step-wise changes in soil water content along the tube were highly correlated to those of extracted core samples (R2 = 0.99 and RMSE = 0.012 cm3 cm-3). The drip emitter tests illustrated spatial hydrodynamics of water infiltration around the access tube. These results illustrate potential applications for this sensing approach, yielding one-dimensional monitoring of soil water along a horizontal line in the root zone or deeper subsurface. Future developments should explore performance in longer and potentially curvilinear pipes for environmental and engineering applications.

  4. Evolution of early male-killing in horizontally transmitted parasites.

    PubMed

    Bernhauerová, Veronika; Berec, Luděk; Maxin, Daniel

    2015-11-01

    Early male-killing (MK) bacteria are vertically transmitted reproductive parasites which kill male offspring that inherit them. Whereas their incidence is well documented, characteristics allowing originally non-MK bacteria to gradually evolve MK ability remain unclear. We show that horizontal transmission is a mechanism enabling vertically transmitted bacteria to evolve fully efficient MK under a wide range of host and parasite characteristics, especially when the efficacy of vertical transmission is high. We also show that an almost 100% vertically transmitted and 100% effective male-killer may evolve from a purely horizontally transmitted non-MK ancestor, and that a 100% efficient male-killer can form a stable coexistence only with a non-MK bacterial strain. Our findings are in line with the empirical evidence on current MK bacteria, explain their high efficacy in killing infected male embryos and their variability within and across insect taxa, and suggest that they may have evolved independently in phylogenetically distinct species.

  5. Horizontal air drilling increases gas recovery in depleted zone

    SciTech Connect

    Elrod, J.P.

    1997-06-30

    Increased gas recoveries in depleted gas zones can be achieved through horizontal air drilling. In December 1995, OXY USA Inc. drilled the Pirkle 2, the first air-drilled horizontal well in the Carthage field of Texas. Targeting the Cretaceous Frost ``A`` zone of the lower Pettit limestone at 6,000 ft true vertical depth, the well established production in a 1,400 ft lateral section with a bottom hole pressure (BHP) of 185 psi. The initial BHP for the zone was 3,280 psi in 1942. As of April 27, 1997, the Pirkle 2 had produced 530 MMcf of gas at a rate of 1.1 MMcfd. Total cumulative gas production for the lower Pettit limestone in the Carthage field was 3.83 tcf as of January 1997. The paper discusses reservoir properties, abandonment pressure, minimizing well bore damage, drilling fluid selection, special equipment and modifications, compressors, BOPs, steering tools, drilling, completion, and production.

  6. 10. RW Meyer Sugar Mill: 18761889. Simple, singlecylinder, horizontal, reciprocating ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. RW Meyer Sugar Mill: 1876-1889. Simple, single-cylinder, horizontal, reciprocating steam engine, model No. 1, 5' x 10', 6 hp, 175 rpm. Manufactured by Ames Iron Works, Oswego, New York, 1879. View: Steam engine powered the mill's centrifugals. To the left of the horizontal (fluted) cylinder is the water pump which moved the boiler feed water through the engine's pre-heat system (the exhaust steam heated the boiler feedwater before it was pumped on to the boiler). The steam-feed port, manual throttle valve, and fly-ball governor and pulley and to the right of the cylinder. The drive shaft with flywheel to the left and pulley to the right are seen behind the piston rod, cross-head, wrist pen, connecting rod and the slide valve and eccentric. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

  7. Boiling heat transfer enhancement in subsurface horizontal and vertical tunnels

    SciTech Connect

    Pastuszko, Robert

    2008-09-15

    Complex experimental investigations of boiling heat transfer on structured surfaces covered with perforated foil were taken up. Experimental data were discussed for two kinds of enhanced surfaces formed by joined horizontal and vertical tunnels: tunnel structures (TS) and narrow tunnel structures (NTS). The experiments were carried out with water, ethanol and R-123 at atmospheric pressure. The TS and NTS surfaces were manufactured out of perforated copper foil of 0.05 mm thickness (hole diameters: 0.3, 0.4, 0.5 mm) sintered with the mini-fins, formed on the vertical side of the 5 mm high rectangular fins and horizontal inter-fin surface. The effects of hole (pore) diameters, tunnel pitch for TS and tunnel width for NTS on nucleate pool boiling were examined. Substantial enhancement of heat transfer coefficient was observed. The investigated surfaces showed boiling heat transfer coefficients similar to those of existing structures with subsurface tunnels, but at higher heat fluxes range. (author)

  8. Evaluation of Horizontal Seismic Hazard of Shahrekord, Iran

    SciTech Connect

    Amiri, G. Ghodrati; Dehkordi, M. Raeisi; Amrei, S. A. Razavian; Kamali, M. Koohi

    2008-07-08

    This paper presents probabilistic horizontal seismic hazard assessment of Shahrekord, Iran. It displays the probabilistic estimate of Peak Ground Horizontal Acceleration (PGHA) for the return period of 75, 225, 475 and 2475 years. The output of the probabilistic seismic hazard analysis is based on peak ground acceleration (PGA), which is the most common criterion in designing of buildings. A catalogue of seismic events that includes both historical and instrumental events was developed and covers the period from 840 to 2007. The seismic sources that affect the hazard in Shahrekord were identified within the radius of 150 km and the recurrence relationships of these sources were generated. Finally four maps have been prepared to indicate the earthquake hazard of Shahrekord in the form of iso-acceleration contour lines for different hazard levels by using SEISRISK III software.

  9. Horizontal flow and capillarity-driven redistribution in porous media.

    PubMed

    Doster, F; Hönig, O; Hilfer, R

    2012-07-01

    A recent macroscopic mixture theory for two-phase immiscible displacement in porous media has introduced percolating and nonpercolating phases. Quasi-analytic solutions are computed and compared to the traditional theory. The solutions illustrate physical insights and effects due to spatiotemporal changes of nonpercolating phases, and they highlight the differences from traditional theory. Two initial and boundary value problems are solved in one spatial dimension. In the first problem a fluid is displaced by another fluid in a horizontal homogeneous porous medium. The displacing fluid is injected with a flow rate that keeps the saturation constant at the injection point. In the second problem a horizontal homogeneous porous medium is considered which is divided into two subdomains with different but constant initial saturations. Capillary forces lead to a redistribution of the fluids. Errors in the literature are reported and corrected.

  10. Horizontal and Slant-Path Surveillance with Speckle Imaging

    SciTech Connect

    Carrano, C J; Brase, J M

    2002-08-19

    A fundamental problem in providing high-quality surveillance images recorded over long horizontal or slant paths is the blurring caused by atmospheric turbulence, which reduces both the resolution and contrast. The objective of the work reported here is to develop a capability for long-range imaging through the atmosphere that is not limited by the atmosphere but only by the fundamental diffraction limit of the optics. This paper describes our recent horizontal and slant-path imaging experiments of point targets and extended scenes as well as simulations of point targets in comparison to experiment. We show the near-diffraction limited resolution results obtained using bispectral speckle-imaging techniques. The experiments were performed with an 8-inch diameter telescope placed either in a field, on a rooftop, or on a hillside and cover ranges of interest from 100 meters up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures.

  11. Growth of horizontally aligned dense carbon nanotubes from trench sidewalls.

    PubMed

    Lu, Jingyu; Miao, Jianmin; Xu, Ting; Yan, Bin; Yu, Ting; Shen, Zexiang

    2011-07-01

    Horizontally aligned, dense carbon nanotubes (HADCNTs) in the form of CNT cantilevers/bridges were grown from selected trench sidewalls in silicon substrate by chemical vapor deposition (CVD). The as-grown CNT cantilevers/bridges are packed with multiwalled carbon nanotubes (MWCNTs) with a linear density of about 10 CNTs µm(-1). The excellent horizontal alignment of these CNTs is mainly ascribed to the van der Waals interactions within the dense CNT bundles. What is more, the Raman intensity ratio I(G)/I(D) shows a gradual increase from the CNT roots to tips, indicating a defect gradient along CNTs generated during their growth. These results will inspire further efforts to explore the fundamentals and applications of HADCNTs. PMID:21586807

  12. Multiple Tune Jumps to Overcome Horizontal Depolarizing Resonances

    NASA Astrophysics Data System (ADS)

    Huang, H.; Ahrens, L. A.; Bai, M.; Brown, K. A.; Dutheil, Y.; Gardner, C.; Glenn, J. W.; Lin, F.; Mackay, W. W.; Meot, F.; Poblaguev, A.; Ranjbar, V.; Roser, T.; Schoefer, V.; Tepikian, S.; Tsoupas, N.; Yip, K.; Zelenski, A.; Zeno, K.

    2016-02-01

    Imperfection and vertical intrinsic depolarizing resonances have been overcome by the two partial Siberian snakes in the Alternative Gradient Synchrotron(AGS). The relatively weak but numerous horizontal resonances are the main source of polarization loss in the AGS. A pair of horizontal tune jump quads have been used to overcome these weak resonances. The locations of the two quads have to be chosen such that the disturbance to the beam optics is minimum. The emittance growth has to be mitigated for this method to work. In addition, this technique needs very accurate jump timing. Using two partial Siberian snakes, with vertical tune inside the spin tune gap and 80% polarization at AGS injection, polarized proton beam had reached 1.5 × 1011 proton per bunch with 65% polarization. With the tune jump timing optimized and emittance preserved, more than 70% polarization with 2 × 1011 protons per bunch has been achieved.

  13. Horizontal integration of the basic sciences in the chiropractic curriculum.

    PubMed

    Ward, Kevin P

    2010-01-01

    Basic science curricula at most chiropractic colleges consist of courses (eg, general anatomy, physiology, biochemistry, etc) that are taught as stand-alone content domains. The lack of integration between basic science disciplines causes difficulties for students who need to understand how the parts function together as an integrated whole and apply this understanding to solving clinical problems. More horizontally integrated basic science curricula could be achieved by several means: integrated Part I National Board of Chiropractic Examiners questions, a broader education for future professors, an increased emphasis on integration within the current model, linked courses, and an integrated, thematic basic science curriculum. Horizontally integrating basic science curricula would require significant efforts from administrators, curriculum committees, and instructional faculty. Once in place this curriculum would promote more clinically relevant learning, improved learning outcomes, and superior vertical integration.

  14. Horizontally integrated atmospheric heat flux from an Arctic lead

    NASA Astrophysics Data System (ADS)

    Glendening, John W.

    1995-03-01

    Vertical distribution of the horizontally integrated heat injected into the atmosphere by an Arctic lead is investigated, based upon large-eddy simulations of its convective plume. The horizontally integrated heat flux varies exponentially with height except under conditions of relatively weak cross flow, when vertical advective transport becomes significant. Its vertical scale, which depends upon the lead size, surface heat flux, atmospheric stratification, and cross-lead wind component, is approximately one fourth of the maximum plume height, indicating that the depth of largest heat transfer is significantly shallower than the depth of the plume. A parameterization is developed to incorporate this small-scale heat injection into large-scale models which cannot resolve individual leads. The amount of heat recaptured by the ice downwind of a lead is significant when cross-lead flow is relatively strong and when the plume depth is shallow.

  15. Advanced high performance horizontal piezoelectric hybrid synthetic jet actuator

    NASA Technical Reports Server (NTRS)

    Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor)

    2012-01-01

    The present invention comprises a high performance, horizontal, zero-net mass-flux, synthetic jet actuator for active control of viscous, separated flow on subsonic and supersonic vehicles. The present invention is a horizontal piezoelectric hybrid zero-net mass-flux actuator, in which all the walls of the chamber are electrically controlled synergistically to reduce or enlarge the volume of the synthetic jet actuator chamber in three dimensions simultaneously and to reduce or enlarge the diameter of orifice of the synthetic jet actuator simultaneously with the reduction or enlargement of the volume of the chamber. The present invention is capable of installation in the wing surface as well as embedding in the wetted surfaces of a supersonic inlet. The jet velocity and mass flow rate for the SJA-H will be several times higher than conventional piezoelectric actuators.

  16. The evolution of horizontal-branch stars - Theoretical sequences

    NASA Technical Reports Server (NTRS)

    Lee, Young-Wook; Demarque, Pierre

    1990-01-01

    A new grid of standard (i.e., solar CNO/Fe, no core rotation, and including semiconvection) horizontal-branch evolutionary sequences are presented which extend the grid of Sweigart both by including the final phase of core helium exhaustion and by using a finer grid of compositions. These sequences were constructed specifically for the studies of the Sandage period-shift effect and the second parameter phenomenon among the Galactic globular clusters. The numerical results for the observable characteristics of the sequences are tabulated which can be directly used to synthesize the observed horizontal-branch distributions. The present computations suggest that the observed difference in period change of RR Lyrae stars in the globular clusters M3 and M15 could be attributed, at least in the mean, to stellar evolution.

  17. Downwind rotor horizontal axis wind turbine noise prediction

    NASA Technical Reports Server (NTRS)

    Metzger, F. B.; Klatte, R. J.

    1981-01-01

    NASA and industry are currently cooperating in the conduct of extensive experimental and analytical studies to understand and predict the noise of large, horizontal axis wind turbines. This effort consists of (1) obtaining high quality noise data under well controlled and documented test conditions, (2) establishing the annoyance criteria for impulse noise of the type generated by horizontal axis wind turbines with rotors downwind of the support tower, (3) defining the wake characteristics downwind of the axial location of the plane of rotation, (4) comparing predictions with measurements made by use of wake data, and (5) comparing predictions with annoyance criteria. The status of work by Hamilton Standard in the above areas which was done in support of the cooperative NASA and industry studies is briefly summarized.

  18. Effects of structure flexibility on horizontal axis wind turbine performances

    NASA Astrophysics Data System (ADS)

    Coiro, D. P.; Daniele, E.; Scherillo, F.

    2013-10-01

    This work illustrates the effects of flexibility of rotor blades and turbine tower on the performances of an horizontal axis wind turbine (HAWT) designed by our ADAG research group, by means of several example applied on a recent project for a active pitch controlled upwind 60 kW HAWT. The influence of structural flexibility for blade only, tower only and blade coupled with tower configuration is investigated using an aero-elastic computer-aided engineering (CAE) tool for horizontal axis wind turbines named FAST developed at National Renewable Energy Laboratory (NREL) of USA. For unsteady inflow conditions in front of the isolated HAWT the performances in rigid and flexible operation mode are computed and compared in order to illustrate the limitation included within a classical rigid body approach to wind turbine simulation.

  19. Vertical versus scanning lidar measurements in a horizontally homogeneous atmosphere.

    PubMed

    Adam, Mariana

    2012-07-01

    This study compares the aerosol backscatter and extinction coefficients retrieved from vertical elastic and Raman channels with those derived from measurements with multiangle elastic channels. Retrievals from simulated vertical signals at 355 nm, 387 nm, 532 nm, and 607 nm are compared with those from multiangle measurements (at 15 elevation angles) at 355 nm and 532 nm. The atmosphere is considered horizontally homogeneously stratified. For the backscatter coefficient, the Raman backscatter solution and the multiangle solution are considered. For the extinction coefficient, retrievals from the Raman channel and multiangle measurements are compared. The comparison shows that in the presence of horizontal homogeneity, multiangle measurements provide more reliable results, especially for the aerosol extinction coefficient. The uncertainty in the measured signals is considered in an alternative approach to quantify the relative error of the retrieved profiles with respect to the models (linear regression between retrieval and model). PMID:22772123

  20. Horizontal Wind Measurements using the HARLIE Holographic Lidar

    NASA Technical Reports Server (NTRS)

    Wilkerson, Thomas; Andrus, Ionio; Sanders, Jason; Schwemmer, Geary; Miller, David; Guerra, David; Starr, David OC. (Technical Monitor)

    2001-01-01

    We report the results of three campaigns in which the horizontal wind vector at cloud altitudes was measured using the holographic, conical-scan lidar HARLIE in its nadir-viewing mode. Measurements were made during the HOLO-1 and -2 tests in Utah and New Hampshire in March and June 1999, respectively, and at the DoE-ARM site in Oklahoma in September/October 2000. A novel algorithm facilitates the wind vector analysis of the HARLIE data. Observed wind velocity and direction were compared with radiosonde records and with other data obtained from video cloud imagery and independent lidar ranging. The results demonstrate good agreement between HARLIE data and the results of other methods. The conically scanning holographic lidar opens up new possibilities for obtaining the vertical profile of horizontal winds.

  1. Horizontal film balance having wide range and high sensitivity

    DOEpatents

    Abraham, B.M.; Miyano, K.; Ketterson, J.B.

    1981-03-05

    A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed.

  2. Horizontal and vertical concentrations in the evolution of hospital competition.

    PubMed

    Starkweather, D B; Carman, J M

    1987-01-01

    Summing across the three phases, the pattern of evolution was as follows: (1) the emergence of a market orientation by hospitals as the industry moved away from regulation; (2) steady expansion of what the hospitals considered to be their business, to include nonacute and wellness services, with vertical integration and diversification the vehicle for accomplishing this; (3) remarkable change with respect to who was competing with whom, stemming from restructuring of the market toward horizontal concentration and domination by a few rather than continuing open competition among many; (4) a shift in the market from one of competitive consumer choices among physicians and hospitals toward one of competitive choice among health plans; and (5) the beginnings of price dynamics within the context of oligopoly, due primarily to heightened power of corporate and other purchasers. A striking feature of this evolution was the role of concentration as both a response to increased competition and a vector of change in restructuring the market. Another notable feature was the relationship of vertical and horizontal integrations to each other: Stage I corporate reorganization and limited vertical integration provided the vehicle for horizontal integration in Stage II; then horizontal integration achieved a new critical mass and market dominance, yielding more vertical integration in Stage III. Finally, we note that of the numerous reasons advanced for mergers in industrial sectors and among hospitals in particular, a singular motivation was pursued in Community A: in an era of increasing competition, the stronger hospitals moved with determination to reduce competition and establish domination. The fundamental motive was market control. PMID:10291980

  3. Detection of homologous horizontal gene transfer in SNP data

    2012-07-23

    We study the detection of mutations, sequencing errors, and homologous horizontal gene transfers (HGT) in a set of closely related microbial genomes. We base the model on single nucleotide polymorphisms (SNP's) and break the genomes into blocks to handle the rearrangement problem. Then we apply a synamic programming algorithm to model whether changes within each block are likely a result of mutations, sequencing errors, or HGT.

  4. Clinical Results of Meniscal Repair Using Submeniscal Horizontal Sutures

    PubMed Central

    Navali, Amir Mohammad; Aslani, Hossein

    2015-01-01

    Background: Parts of the implants placed over the meniscus during meniscal repair can wear down the cartilage in the contact zones and cause chronic synovitis. Placing horizontal sutures under the meniscus may overcome this potential hazard. The purpose of this prospective study was to evaluate the midterm results of arthroscopic meniscal repair using submeniscally placed out-in horizontal sutures. Methods: One hundred and three meniscal repairs with submeniscal horizontal out-in technique in 103 patients were performed between 2009 and 2012. Our indications for meniscal repair were all longitudinal tear in red-red and red-white zone with acceptable tissue quality. Clinical evaluation included the Tegner and Lysholm knee scores and clinical success was defined as absence of joint-line tenderness, locking, swelling, and a negative McMurray test. Results: The average follow-up was 19 months (range, 14 to 40 months). The time interval from injury to meniscal repair ranged from 2 days to 390 days (median, 96 days). At the end of follow-up, the clinical success rate was 86.5%. Fourteen of 103 repaired menisci (13.5%) were considered failures according to Barrett’s criteria. The mean Lysholm score significantly improved from 39.6 preoperatively to 84.5 postoperatively (P<0.001). Eighty five patients (82.5%) had an excellent or good result according to Lysholm knee score. Tegner activity score improved significantly (P<0.01) from an average of 3.4 (range, 2-6) preoperatively to 5.9 (range, 5-8) postoperatively. Statistical analysis showed that age, simultaneous anterior cruciate ligament reconstruction, chronicity of injury did not affect the clinical outcome. Conclusion: Our results showed that acceptable midterm results are expected from submeniscal horizontal out-in repair technique. This technique is cheap, safe and has the advantage of avoiding chondral abrasion caused by solid implants and suture materials placed over the meniscus. PMID:26213701

  5. Extensive analysis critical for horizontal well tie-in

    SciTech Connect

    Wilson, A.; Hartmann, C. )

    1990-07-02

    The design of the tie-in of the Gamma North field's horizontal well to the Oseberg field complex required extensive analysis of the physical properties, hydrate evaluation, material studies, and multiphase flow. The physical property generation was based on in-house procedures that to a large extent are applications of the Gas Processors Association (GPA) developed techniques and method. Experimental verifications have confirmed the need for these predictions.

  6. Photographic copy of plan of new Dy horizontal station and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Photographic copy of plan of new Dy horizontal station and accumulator additions to Test Stand "D," also showing existing Dd test station. JPL drawing by VTN Consolidated, Inc. Engineers, Architects, Planners, 2301 Campus Drive, Irvine, California 92664: "Jet Propulsion Laboratory-Edwards Test Station, Motive Steam Supply & Ejector Pumping System: Plan - Test Stand "D," sheet M-3 (JPL sheet number E24/33), 21 December 1976 - Jet Propulsion Laboratory Edwards Facility, Test Stand D, Edwards Air Force Base, Boron, Kern County, CA

  7. A shear horizontal surface wave in magnetoelectric materials.

    PubMed

    Liu, Jinxi; Fang, Daining; Liu, Xiangling

    2007-07-01

    We show that a semi-infinite magnetoelectric (ME) material adjoining a vacuum sustains the propagation of a shear horizontal wave accompanied by electromagnetic waves. The ME material is assumed to possess hexagonal (6 mm) symmetry. The expression for the phase velocity of this wave is obtained explicitly. The result is helpful for applications of piezoelectric-piezomagnetic composites to acoustic wave and microwave devices.

  8. DIVERGENT HORIZONTAL SUB-SURFACE FLOWS WITHIN ACTIVE REGION 11158

    SciTech Connect

    Jain, Kiran; Tripathy, S. C.; Hill, F. E-mail: stripathy@nso.edu

    2015-07-20

    We measure the horizontal subsurface flow in a fast emerging active region (AR; NOAA 11158) using the ring-diagram technique and the Helioseismic and Magnetic Imager high spatial resolution Dopplergrams. This AR had a complex magnetic structure and displayed significant changes in morphology during its disk passage. Over a period of six days from 2011 February 11 to 16, the temporal variation in the magnitude of the total velocity is found to follow the trend of magnetic field strength. We further analyze regions of individual magnetic polarity within AR 11158 and find that the horizontal velocity components in these sub-regions have significant variation with time and depth. The leading and trailing polarity regions move faster than the mixed-polarity region. Furthermore, both zonal and meridional components have opposite signs for trailing and leading polarity regions at all depths showing divergent flows within the AR. We also find a sharp decrease in the magnitude of total horizontal velocity in deeper layers around major flares. It is suggested that the re-organization of magnetic fields during flares, combined with the sunspot rotation, decreases the magnitude of horizontal flows or that the flow kinetic energy has been converted into the energy released by flares. After the decline in flare activity and sunspot rotation, the flows tend to follow the pattern of magnetic activity. We also observe less variation in the velocity components near the surface but these tend to increase with depth, further demonstrating that the deeper layers are more affected by the topology of ARs.

  9. Horizontal and vertical concentrations in the evolution of hospital competition.

    PubMed

    Starkweather, D B; Carman, J M

    1987-01-01

    Summing across the three phases, the pattern of evolution was as follows: (1) the emergence of a market orientation by hospitals as the industry moved away from regulation; (2) steady expansion of what the hospitals considered to be their business, to include nonacute and wellness services, with vertical integration and diversification the vehicle for accomplishing this; (3) remarkable change with respect to who was competing with whom, stemming from restructuring of the market toward horizontal concentration and domination by a few rather than continuing open competition among many; (4) a shift in the market from one of competitive consumer choices among physicians and hospitals toward one of competitive choice among health plans; and (5) the beginnings of price dynamics within the context of oligopoly, due primarily to heightened power of corporate and other purchasers. A striking feature of this evolution was the role of concentration as both a response to increased competition and a vector of change in restructuring the market. Another notable feature was the relationship of vertical and horizontal integrations to each other: Stage I corporate reorganization and limited vertical integration provided the vehicle for horizontal integration in Stage II; then horizontal integration achieved a new critical mass and market dominance, yielding more vertical integration in Stage III. Finally, we note that of the numerous reasons advanced for mergers in industrial sectors and among hospitals in particular, a singular motivation was pursued in Community A: in an era of increasing competition, the stronger hospitals moved with determination to reduce competition and establish domination. The fundamental motive was market control.

  10. Method for culturing mammalian cells in a horizontally rotated bioreactor

    NASA Technical Reports Server (NTRS)

    Schwarz, Ray P. (Inventor); Wolf, David A. (Inventor); Trinh, Tinh T. (Inventor)

    1992-01-01

    A bio-reactor system where cell growth microcarrier beads are suspended in a zero head space fluid medium by rotation about a horizontal axis and where the fluid is continuously oxygenated from a tubular membrane which rotates on a shaft together with rotation of the culture vessel. The oxygen is continuously throughput through the membrane and disbursed into the fluid medium along the length of the membrane.

  11. Horizontal film balance having wide range and high sensitivity

    DOEpatents

    Abraham, Bernard M.; Miyano, Kenjiro; Ketterson, John B.

    1983-01-01

    A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed.

  12. Horizontal film balance having wide range and high sensitivity

    DOEpatents

    Abraham, B.M.; Miyano, K.; Ketterson, J.B.

    1983-11-08

    A thin-film, horizontal balance instrument is provided for measuring surface tension (surface energy) of thin films suspended on a liquid substrate. The balance includes a support bearing and an optical feedback arrangement for wide-range, high sensitivity measurements. The force on the instrument is balanced by an electromagnet, the current through the magnet providing a measure of the force applied to the instrument. A novel float construction is also disclosed. 5 figs.

  13. A Horizontal Brazil-Nut Effect and Its Reverse

    NASA Astrophysics Data System (ADS)

    Schnautz, T.; Brito, R.; Kruelle, C. A.; Rehberg, I.

    2005-07-01

    Transport effects in a monolayer consisting of a binary granular mixture, confined in a horizontally vibrating circular dish, are studied experimentally and compared with a reduced theoretical model. Depending on the ratio of the particles’ material density and size, migration of the larger particles occurs either towards the boundary or to the center of the circular container. These directed motions show similarities to the Brazil-nut effect and its reverse form.

  14. 24 CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

    SciTech Connect

    Erik C. Westman

    2002-07-01

    This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method of emplacing the array in a long, horizontal borehole. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.

  15. A Simple Model of Cirrus Horizontal Inhomogeneity and Cloud Fraction

    NASA Technical Reports Server (NTRS)

    Smith, Samantha A.; DelGenio, Anthony D.

    1998-01-01

    A simple model of horizontal inhomogeneity and cloud fraction in cirrus clouds has been formulated on the basis that all internal horizontal inhomogeneity in the ice mixing ratio is due to variations in the cloud depth, which are assumed to be Gaussian. The use of such a model was justified by the observed relationship between the normalized variability of the ice water mixing ratio (and extinction) and the normalized variability of cloud depth. Using radar cloud depth data as input, the model reproduced well the in-cloud ice water mixing ratio histograms obtained from horizontal runs during the FIRE2 cirrus campaign. For totally overcast cases the histograms were almost Gaussian, but changed as cloud fraction decreased to exponential distributions which peaked at the lowest nonzero ice value for cloud fractions below 90%. Cloud fractions predicted by the model were always within 28% of the observed value. The predicted average ice water mixing ratios were within 34% of the observed values. This model could be used in a GCM to produce the ice mixing ratio probability distribution function and to estimate cloud fraction. It only requires basic meteorological parameters, the depth of the saturated layer and the standard deviation of cloud depth as input.

  16. Horizontal drilling in the Austin Chalk: Stratigraphic factors

    SciTech Connect

    Durham, C.O. Jr. ); Bobigian, R.A. )

    1990-05-01

    Horizontal drilling has renewed interest in the Austin chalk in south-central Texas. Large fields on opposite sides of the San Marcos arch Giddings to the northeast and Pearsall to the southwest were active with vertical drilling 10 years ago. Giddings' 4,500 Austin wells produced 209 million BO and 934 bcfg of gas through 1988; Pearsall's 1,440 wells produced 57 million BO and 35 bcfg of gas. Most vertical wells were completed, 20% were economic successes, 40% were marginal, 40% were uneconomic due to uneven areal distribution of near-vertical fractures and small faults, which provide reservoirs in otherwise tight chalk. Horizontal drilling, led by Amoco in Giddings and Oryx in Pearsall, enhances the chances of encountering the fractures by drilling perpendicular to the fracture trend. Horizontal drilling requires preselection of the stratigraphic horizon to be penetrated. One must understand the variable Austin stratigraphy to choose the zone with the most brittle character and best matrix porosity, both reduced by increased clay content. Chalk 130 ft thick on the San Marcos arch thickens to 600 to 800 ft in central Giddings field where middle marl separates lower and upper chalk Northeastward only lower chalk is preserved beneath a post-Austin submarine channel. The Austin thickens to 300-500 ft in Pearsall field where middle member ash beds separate lower and upper chalk inhibiting vertical reservoir communication. Locally, on the Pearsall arch, ash is missing, lower chalk thickens, and upper chalk thins.

  17. Natural convection heat transfer within horizontal spent nuclear fuel assemblies

    SciTech Connect

    Canaan, R.E.

    1995-12-01

    Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.

  18. Borehole Stability Analysis of Horizontal Drilling in Shale Gas Reservoirs

    NASA Astrophysics Data System (ADS)

    Yuan, Jun-Liang; Deng, Jin-Gen; Tan, Qiang; Yu, Bao-Hua; Jin, Xiao-Chun

    2013-09-01

    Serious wellbore instability occurs frequently during horizontal drilling in shale gas reservoirs. The conventional forecast model of in situ stresses is not suitable for wellbore stability analysis in laminated shale gas formations because of the inhomogeneous mechanical properties of shale. In this study, a new prediction method is developed to calculate the in situ stresses in shale formations. The pore pressure near the borehole is heterogeneous along both the radial and tangential directions due to the inhomogeneity in the mechanical properties and permeability. Therefore, the stress state around the wellbore will vary with time after the formation is drained. Besides, based on the experimental results, a failure criterion is verified and applied to determine the strength of Silurian shale in the Sichuan Basin, including the long-term strength of gas shale. Based on this work, horizontal well borehole stability is analyzed by the new in situ stress prediction model. Finally, the results show that the collapse pressure will be underestimated if the conventional model is used in shale gas reservoirs improperly. The collapse pressure of a horizontal well is maximum at dip angle of 45°. The critical mud weight should be increased constantly to prevent borehole collapse if the borehole is exposed for some time.

  19. The role of vertical shear on the horizontal oceanic dispersion

    NASA Astrophysics Data System (ADS)

    Lanotte, A. S.; Corrado, R.; Lacorata, G.; Palatella, L.; Pizzigalli, C.; Schipa, I.; Santoleri, R.

    2015-09-01

    The effect of vertical shear on the horizontal dispersion properties of passive tracer particles on the continental shelf of South Mediterranean is investigated by means of observative and model data. In-situ current measurements reveal that vertical velocity gradients in the upper mixed layer decorrelate quite fast (∼ 1 day), whereas basin-scale ocean circulation models tend to overestimate such decorrelation time because of finite resolution effects. Horizontal dispersion simulated by an eddy-permitting ocean model, like, e.g., the Mediterranean Forecasting System, is mosty affected by: (1) unresolved scale motions, and mesoscale motions that are largely smoothed out; (2) poorly resolved time variability of vertical velocity profiles in the upper layer. For the case study we have analysed, we show that a suitable use of kinematic parameterisations is helpful to implement realistic statistical features of tracer dispersion in two and three dimensions. The approach here suggested provides a functional tool to control the horizontal spreading of small organisms or substance concentrations, and is thus relevant for marine biology, pollutant dispersion as well as oil spill applications.

  20. Rock characterization in reservoirs targeted for horizontal drilling

    SciTech Connect

    Skopec, R.A. )

    1993-12-01

    Achieving the maximum economic benefit from horizontal drilling requires thorough understanding of reservoir characteristics. The direct measurement of rock properties from oriented core is critical in horizontal-wellbore design. This paper outlines the measures and testing necessary to evaluate naturally fractured reservoirs effectively with field and laboratory technologies. Rock mechanical properties, fracture strike, and principal in-situ stress magnitudes and directions should be known before a horizontal wellbore is drilled. These data can then be used to maximize the intersection of natural fractures and to minimize the potential of borehole failure. In exploration wells, a vertical pilot hole must first be drilled. The zone of interest is cored, field tests are performed, laboratory testing is completed, and the reservoir is evaluated. With this information available, decisions can be made to optimize the borehole azimuth and well placement. The authors have used this approach to formation evaluation in several reservoirs where rock characterization is essential in the exploration and drilling program. 72 refs., 10 figs.

  1. Horizontal transfer of non-LTR retrotransposons in vertebrates.

    PubMed

    Kordis, D; Gubensek, F

    1999-01-01

    Since their discovery in family Bovidae (bovids), Bov-B LINEs, believed to be order-specific SINEs, have been found in all ruminants and recently also in Viperidae snakes. The distribution and the evolutionary relationships of Bov-B LINEs provide an indication of their origin and evolutionary dynamics in different species. The evolutionary origin of Bov-B LINE elements has been shown unequivocally to be in Squamata (squamates). The horizontal transfer of Bov-B LINE elements in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The direction of horizontal transfer from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution of Bov-B LINE elements. The ancestral snake lineage (Boidae) has been recognized as a possible donor of Bov-B LINE elements to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINE elements in Ruminantia and the fossil data of Ruminantia to be 40-50 mya. The phylogenetic relationships of Bov-B LINE elements from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINE elements have been stably maintained by vertical transmission since the origin of Squamata in the Mesozoic era.

  2. Comparing reading speed for horizontal and vertical English text.

    PubMed

    Yu, Deyue; Park, Heejung; Gerold, David; Legge, Gordon E

    2010-02-23

    There are three formats for arranging English text for vertical reading-upright letters arranged vertically (marquee), and horizontal text rotated 90 degrees clockwise or counterclockwise. Previous research has shown that reading is slower for all three vertical formats than for horizontal text, with marquee being slowest (M. D. Byrne, 2002). It has been proposed that the size of the visual span-the number of letters recognized with high accuracy without moving the eyes-is a visual factor limiting reading speed. We predicted that reduced visual-span size would be correlated with the slower reading for the three vertical formats. We tested this prediction with uppercase and lowercase letters. Reading performance was measured using two presentation methods: RSVP (Rapid Serial Visual Presentation) and flashcard (a block of text on four lines). On average, reading speed for horizontal text was 139% faster than marquee text and 81% faster than the rotated texts. Size of the visual span was highly correlated with changes in reading speed for both lowercase and uppercase letters and for both RSVP and flashcard reading. Our results are consistent with the view that slower reading of vertical text is due to a decrease in the size of the visual span for vertical reading.

  3. Changes in monkey horizontal semicircular canal afferent responses after spaceflight

    NASA Technical Reports Server (NTRS)

    Correia, M. J.; Perachio, A. A.; Dickman, J. D.; Kozlovskaia, I. B.; Sirota, M. G.; Iakushin, S. B.; Beloozerova, I. N.

    1992-01-01

    Extracellular responses from single horizontal semicircular canal afferents in two rhesus monkeys were studied after recovery from a 14-day biosatellite (Cosmos 2044) orbital spaceflight. On the 1st postflight day, the mean gain for 9 different horizontal canal afferents, tested using one or several different passive yaw rotation waveforms, was nearly twice that for 20 horizontal canal afferents similarly tested during preflight and postflight control studies. Adaptation of the afferent response to passive yaw rotation on the 1st postflight day was also greater. These results suggest that at least one component of the vestibular end organ (the semicircular canals) is transiently modified after exposure to 14 days of microgravity. It is unclear whether the changes are secondary to other effects of microgravity, such as calcium loss, or an adaptive response. If the response is adaptive, then this report is the first evidence that the response of the vestibular end organ may be modified (presumably by the central nervous system via efferent connections) after prolonged unusual vestibular stimulation. If this is the case, the sites of plasticity of vestibular responses may not be exclusively within central nervous system vestibular structures, as previously believed.

  4. Horizontal natural gas storage caverns and methods for producing same

    DOEpatents

    Russo, Anthony

    1995-01-01

    The invention provides caverns and methods for producing caverns in bedded salt deposits for the storage of materials that are not solvents for salt. The contemplated salt deposits are of the bedded, non-domed variety, more particularly salt found in layered formations that are sufficiently thick to enable the production of commercially usefully sized caverns completely encompassed by walls of salt of the formation. In a preferred method, a first bore hole is drilled into the salt formation and a cavity for receiving insolubles is leached from the salt formation. Thereafter, at a predetermined distance away from the first bore hole, a second bore hole is drilled towards the salt formation. As this drill approaches the salt, the drill assumes a slant approach and enters the salt and drills through it in a horizontal direction until it intersects the cavity for receiving insolubles. This produces a substantially horizontal conduit from which solvent is controlledly supplied to the surrounding salt formation, leaching the salt and producing a concentrated brine which is removed through the first bore hole. Insolubles are collected in the cavity for receiving insolubles. By controlledly supplying solvent, a horizontal cavern is produced with two bore holes extending therefrom.

  5. Overcoming horizontal depolarizing resonances with multiple tune jumps

    NASA Astrophysics Data System (ADS)

    Huang, H.; Ahrens, L. A.; Bai, M.; Brown, K. A.; Dutheil, Y.; Gardner, C.; Glenn, J. W.; Lin, F.; MacKay, W. W.; Meot, F.; Poblaguev, A.; Ranjbar, V.; Roser, T.; Schoefer, V.; Tepikian, S.; Tsoupas, N.; Yip, K.; Zelenski, A.; Zeno, K.

    2014-08-01

    In a medium energy proton synchrotron, strong enough partial Siberian snakes can be used to avoid both imperfection and vertical intrinsic depolarizing resonances. However, partial snakes tilt the stable spin direction away from vertical, which generates depolarizing resonances associated with horizontal tune. The relatively weak but numerous horizontal intrinsic resonances are the main source of the residual polarization losses. A pair of horizontal tune jump quads have been used in the Brookhaven Alternating Gradient Synchrotron to overcome these weak resonances. The locations of the two quads have to be chosen such that the disturbance to the beam optics is minimum. The emittance growth has to be mitigated for this method to work. In addition, this technique needs very accurate jump timing. Using two partial Siberian snakes, with vertical tune inside the spin tune gap and 80% polarization at the Alternating Gradient Synchrotron injection, polarized proton beam had reached 1.5×1011 proton per bunch with 65% polarization. With the tune jump timing optimized and emittance preserved, more than 70% polarization with 2×1011 protons per bunch has been achieved. The polarization transport efficiency is close to 90%.

  6. Moral transhumanism: the next step.

    PubMed

    Tennison, Michael N

    2012-08-01

    Although transhumanism offers hope for the transcendence of human biological limitations, it generates many intrinsic and consequential ethical concerns. The latter include issues such as the exacerbation of social inequalities and the exponentially increasing technological capacity to cause harm. To mitigate these risks, many thinkers have initiated investigations into the possibility of moral enhancement that could limit the power disparities facilitated by biotechnological enhancement. The arguments often focus on whether moral enhancement is morally permissible, or even obligatory, and remain largely in the realm of the hypothetical. This paper proposes that psilocybin may represent a viable, practical option for moral enhancement and that its further research in the context of moral psychology could comprise the next step in the development of moral transhumanism.

  7. Staircase Structure of Shapiro Steps

    NASA Astrophysics Data System (ADS)

    Shukrinov, Yu. M.; Rahmonov, I. R.; Nashaat, M.

    2015-12-01

    We investigate IV-characteristics of coupled Josephson junctions which model the intrinsic Josephson junctions in high temperature superconductors under external electromagnetic radiation. A staircase structure of Shapiro steps is found in the branching region. Its origin is related to the coupling between junctions and their switching from rotating to oscillating states. This conclusion is tested by detailed analysis of the IV-characteristics as for total stack and for each junction in the stack. IV-curves of junctions in the stack are compared with the average of time derivative of phase difference. Experimental observation of this staircase structure would give us a proof of coupling between junctions and a way for precise measurement of its value. Such investigations would be also useful for a diagnostic of Josephson junctions in the stack.

  8. A Step by Step Protocol for Subretinal Surgery in Rabbits.

    PubMed

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V

    2016-09-13

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models.

  9. A Step by Step Protocol for Subretinal Surgery in Rabbits.

    PubMed

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V

    2016-01-01

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models. PMID:27684952

  10. Improving airborne strapdown vector gravimetry using stabilized horizontal components

    NASA Astrophysics Data System (ADS)

    Cai, Shaokun; Zhang, Kaidong; Wu, Meiping

    2013-11-01

    Integrating the deflections of the vertical along the flight line can yield geoid profiles which are valuable in the study of geodesy and geophysics, fortunately, the deflections can be measured directly by vector gravimetry. Airborne vector gravimetry using a Strapdown Inertial Navigation System and the Global Navigation Satellite System (SINS/GNSS) has shown promising results in previous studies. However, the quality of the SINS and GNSS is a major limitation; in particular, the attitude errors induced by the gyros will result in large measurement errors to the horizontal components of the gravity disturbance, and these measurement errors represent the behavior of low-frequency trend. An airborne vector gravimetry method used to remove the bias and low-frequency trends in the gravity disturbance estimated for each survey line has been developed. This method uses the horizontal components of the gravity disturbance computed from EGM2008 (Earth Gravitational Model 2008) as a reference. Firstly, the horizontal measurement results obtained from the gravimeter are divided into high- and low-frequency components according to the resolution of the EGM2008, and then, the bias and low-frequency trends of the low-frequency components are corrected using a linear fit to the EGM2008 reference data. Finally, the ultimate results can be acquired after combining the high-frequency components and the corrected low-frequency components. The data used was obtained from the SGA-WZ, which is the first strapdown airborne gravimeter developed in China. The results of this method are promising. The internal accuracy of the gravity disturbance's horizontal components for repeated survey lines exceeds 3.5 mGal, and the corresponding resolution is approximately 4.8 km based on 160-s data smoothing and an airplane averaging speed of approximately 216 km/h. After applying the WCF (Wavenumber Correlation Filter), the internal accuracy of the horizontal components exceeds 2 mGal. This can

  11. Horizontal oil and gas wells prove value in bringing economic sense to tough zones

    SciTech Connect

    Lyle, D.

    1995-10-01

    From the Northeast to the Pacific Coast, horizontal wells make previously uneconomic pay zones look like oilpatch winners. The horizontal revolution has passed, and the nation`s oil and gas industry is moving into a refinement of the technology.

  12. The Hottest Horizontal-Branch Stars in Omega Centauri: Late Hot Flasher vs. Helium Enrichment

    NASA Technical Reports Server (NTRS)

    Moehler, S.; Dreizler, S.; Lanz, T.; Bono, G.; Sweigart, A V.; Calamida, A.; Monelli, M.; Nonino, M.

    2007-01-01

    UV observations of some massive globular clusters uncovered a significant population of very hot stars below the hot end of the horizontal branch (HB), the so-called blue hook stars. This feature might be explained either by the late hot flasher scenario here stars experience the helium flash while on the white dwarf cooling curve or by the helium-rich sub-population recently postulated to exist in some clusters. Spectroscopic analyses of blue hook stars in omega Cen and NGC 2808 support the late hot flasher scenario, but the stars contain much less helium than expected and the predicted C, N enrichment could not be verified from existing data. We want to determine effective temperatures, surface gravities and abundances of He, C, N in blue hook and canonical extreme horizontal branch (EHB) star candidates. Moderately high resolution spectra of stars at the hot end of the blue horizontal branch in the globular cluster omega Cen were analysed for atmospheric parameters (T(sub eff), log g) and abundances using LTE and Non-LTE model atmospheres. In the temperature range 30,000 K to 50,000 K we find that 37% of our stars are helium-poor (log nHe/nH less than -2), 49% have solar helium abundance within a factor of 3 (-1.5 less than or equal to log nHe/nH less than or equal to -0.5) and 14% are helium rich (log nHe/nH greater than -0.4). We also find carbon enrichment in step with helium enrichment, with a maximum carbon enrichment of 3% by mass. At least 30% of the hottest HB stars in omega Centauri show helium abundances well above the predictions from the helium enrichment scenario (Y = 0.42 corresponding to log nHe/nH approximately equal to -0.74). In addition the most helium-rich stars show strong carbon enrichment as predicted by the late hot flasher scenario. We conclude that the helium-rich HB stars in omega Cen cannot be explained solely by the helium-enrichment scenario invoked to explain the blue main sequence.

  13. Neural mechanism of oculomotor horizontal velocity-to- position temporal integration

    NASA Astrophysics Data System (ADS)

    Aksay, Emre R. F.

    Storage of briefly presented information in ``working'' memory correlates with persistent firing in the brain. Persistent activity in response to transient stimulation is a form of neural temporal integration. Here, the mechanism of temporal integration was explored in the oculomotor velocity-to-position neural integrator (VPNI), where persistent activity is used to maintain eye position and fixation. Extracellular and intracellular electrophysiology, single-cell dye- labeling, and pharmacological inactivation were performed in awake behaving goldfish while monitoring eye motion with the scleral search-coil method. Neurons identified within a compact subnucleus in the medulla designated as Area I are part of the VPNI for horizontal eye movements. Neurons fired tonically during fixations, with tonic rate higher for lateral eye positions and no discharge below a threshold position value. Dye-labeled somata were localized in a 350 micron extent of the inferior reticular formation. Axons either projected ipsilaterally to abducens motoneurons, or crossed the midline and projected toward the contralateral Area I and abducens. Bilateral inactivation of Area I induced inability to maintain eccentric gaze. During intracellular recording, step changes in eye position and firing rate were accompanied by steps in underlying membrane potential. Steps remained when neurons were hyperpolarized below action potential threshold. Perturbation with brief intracellular current pulses only induced transient changes in firing rate and potential. Membrane potential fluctuations were greater during more depolarized steps. These results suggest that steps are generated by synaptic input changes rather than intrinsic properties like membrane multistability. Spiking of unilateral pairs was positively correlated with 0-10 ms lag. Bilateral pairs were negatively correlated with 0-10 ms lag. These results are consistent with excitatory connections between unilateral pairs and inhibitory

  14. 76 FR 16394 - Analysis of Horizontal Market Power Under the Federal Power Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-23

    ... Energy Regulatory Commission Analysis of Horizontal Market Power Under the Federal Power Act AGENCY... should revise its approach for examining horizontal ] market power concerns in transactions under Sec. 203 of the Federal Power Act to reflect the Horizontal Merger Guidelines issued by the Department...

  15. Effect of convection on the microstructure of a lamellar eutectic growing with a stepped interface

    NASA Technical Reports Server (NTRS)

    Seth, Jayshree; Wilcox, W. R.

    1990-01-01

    A two dimensional model developed to study the influence of convective flow on the concentration field ahead of a growing lamellar eutectic is described when one phase projects out into the melt creating a stepped interface. The two dimensional convective flow field, which is periodic in the horizontal direction, was computed numerically using the software FLUENT. The velocity field generated due to the flow of melt over the steps was then incorporated into a finite difference scheme employed to solve the concentration field. The average interfacial composition was calculated and converted to lamellar spacing using the Jackson and Hunt minimum supercooling criterion. It was found that a stepped interface is more sensitive to convection than a planar interface.

  16. Effect of convection on the microstructure of a lamellar eutectic growing with a stepped interface

    NASA Technical Reports Server (NTRS)

    Seth, Jayshree; Wilcox, W. R.

    1991-01-01

    A two dimensional model developed to study the influence of convective flow on the concentration field ahead of a growing lamellar eutectic is described when one phase projects out into the melt creating a stepped interface. The two dimensional convective flow field, which is periodic in the horizontal direction, was computed numerically using the software FLUENT. The velocity field generated due to the flow of melt over the steps was then incorporated into a finite difference scheme employed to solve the concentration field. The average interfacial composition was calculated and converted to lamellar spacing using the Jackson and Hunt minimum supercooling criterion. It was found that a stepped interface is more sensitive to convection than a planar interface.

  17. Terrace-width distributions of touching steps: Modification of the fermion analogy with implications for measuring step-step interactions

    NASA Astrophysics Data System (ADS)

    Sathiyanarayanan, Rajesh; Hamouda, Ajmi Bh.; Einstein, T. L.

    2009-10-01

    Using Monte Carlo simulations, we compute the terrace-width distributions (TWDs) of surfaces in which steps can touch each other, forming multiple-atomic height steps, but cannot cross (no overhangs), and so inconsistent with the standard mapping to spinless fermions. Our results show that the generalized Wigner distribution with minor modifications at small step separations, gives a very good fit for TWDs of touching steps. The interaction strength derived from the fit parameter (ϱ) indicates an effective attraction between steps. The strength of this effective attraction decreases for larger mean-step separations and decreasing step-touching energies; describable via finite-size scaling. Hence, accurate extraction of the true repulsion strength requires multiple vicinalities.

  18. Stepping Up to Science and Math

    ERIC Educational Resources Information Center

    Goldston, Dee

    2004-01-01

    "Stepping Up to Science and Math" invites teachers to step back and rethink the way they teach both of these essential subjects. Then it illustrates how teachers can step up the pace with Standards-based activities that make learning more effective and efficient. (New lessons featuring gummy worms, school buses, or the planet Mars help teachers…

  19. 7 CFR 65.230 - Production step.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Production step. 65.230 Section 65.230 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards..., PEANUTS, AND GINSENG General Provisions Definitions § 65.230 Production step. Production step means,...

  20. 7 CFR 60.122 - Production step.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Production step. 60.122 Section 60.122 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... FOR FISH AND SHELLFISH General Provisions Definitions § 60.122 Production step. Production step...

  1. 7 CFR 65.230 - Production step.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Production step. 65.230 Section 65.230 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards..., PEANUTS, AND GINSENG General Provisions Definitions § 65.230 Production step. Production step means,...

  2. Ten Steps to Making Evaluation Matter

    ERIC Educational Resources Information Center

    Sridharan, Sanjeev; Nakaima, April

    2011-01-01

    This paper proposes ten steps to make evaluations matter. The ten steps are a combination of the usual recommended practice such as developing program theory and implementing rigorous evaluation designs with a stronger focus on more unconventional steps including developing learning frameworks, exploring pathways of evaluation influence, and…

  3. Ten steps to successful software process improvement

    NASA Technical Reports Server (NTRS)

    Kandt, R. K.

    2003-01-01

    This paper identifies ten steps for managing change that address organizational and cultural issues. Four of these steps are critical, that if not done, will almost guarantee failure. This ten-step program emphasizes the alignment of business goals, change process goals, and the work performed by the employees of an organization.

  4. STEPS: Moving from Welfare to Work.

    ERIC Educational Resources Information Center

    Vail, Ann; Cummings, Merrilyn; Kratzer, Connie; Galindo, Vickie

    Cooperative extension service faculty at New Mexico State University started the Steps to Employment and Personal Success (STEPS) program to help Temporary Assistance for Needy Families (TANF) clients qualify for and maintain full-time employment and strengthen their families for long-term success. Clients are referred to STEPS by New Mexico…

  5. The 5-Step Method: Principles and Practice

    ERIC Educational Resources Information Center

    Copello, Alex; Templeton, Lorna; Orford, Jim; Velleman, Richard

    2010-01-01

    This article includes a description of the 5-Step Method. First, the origins and theoretical basis of the method are briefly described. This is followed by a discussion of the general principles that guide the delivery of the method. Each step is then described in more detail, including the content and focus of each of the five steps that include:…

  6. Evolution of gene fusions: horizontal transfer versus independent events

    PubMed Central

    Yanai, Itai; Wolf, Yuri I; Koonin, Eugene V

    2002-01-01

    Background Gene fusions can be used as tools for functional prediction and also as evolutionary markers. Fused genes often show a scattered phyletic distribution, which suggests a role for processes other than vertical inheritance in their evolution. Results The evolutionary history of gene fusions was studied by phylogenetic analysis of the domains in the fused proteins and the orthologous domains that form stand-alone proteins. Clustering of fusion components from phylogenetically distant species was construed as evidence of dissemination of the fused genes by horizontal transfer. Of the 51 examined gene fusions that are represented in at least two of the three primary kingdoms (Bacteria, Archaea and Eukaryota), 31 were most probably disseminated by cross-kingdom horizontal gene transfer, whereas 14 appeared to have evolved independently in different kingdoms and two were probably inherited from the common ancestor of modern life forms. On many occasions, the evolutionary scenario also involves one or more secondary fissions of the fusion gene. For approximately half of the fusions, stand-alone forms of the fusion components are encoded by juxtaposed genes, which are known or predicted to belong to the same operon in some of the prokaryotic genomes. This indicates that evolution of gene fusions often, if not always, involves an intermediate stage, during which the future fusion components exist as juxtaposed and co-regulated, but still distinct, genes within operons. Conclusion These findings suggest a major role for horizontal transfer of gene fusions in the evolution of protein-domain architectures, but also indicate that independent fusions of the same pair of domains in distant species is not uncommon, which suggests positive selection for the multidomain architectures. PMID:12049665

  7. Dynamic monitoring of horizontal gene transfer in soil

    NASA Astrophysics Data System (ADS)

    Cheng, H. Y.; Masiello, C. A.; Silberg, J. J.; Bennett, G. N.

    2015-12-01

    Soil microbial gene expression underlies microbial behaviors (phenotypes) central to many aspects of C, N, and H2O cycling. However, continuous monitoring of microbial gene expression in soils is challenging because genetically-encoded reporter proteins widely used in the lab are difficult to deploy in soil matrices: for example, green fluorescent protein cannot be easily visualized in soils, even in the lab. To address this problem we have developed a reporter protein that releases small volatile gases. Here, we applied this gas reporter in a proof-of-concept soil experiment, monitoring horizontal gene transfer, a microbial activity that alters microbial genotypes and phenotypes. Horizontal gene transfer is central to bacterial evolution and adaptation and is relevant to problems such as the spread of antibiotic resistance, increasing metal tolerance in superfund sites, and bioremediation capability of bacterial consortia. This process is likely to be impacted by a number of matrix properties not well-represented in the petri dish, such as microscale variations in water, nutrients, and O2, making petri-dish experiments a poor proxy for environmental processes. We built a conjugation system using synthetic biology to demonstrate the use of gas-reporting biosensors in safe, lab-based biogeochemistry experiments, and here we report the use of these sensors to monitor horizontal gene transfer in soils. Our system is based on the F-plasmid conjugation in Escherichia coli. We have found that the gas signal reports on the number of cells that acquire F-plasmids (transconjugants) in a loamy Alfisol collected from Kellogg Biological Station. We will report how a gas signal generated by transconjugants varies with the number of F-plasmid donor and acceptor cells seeded in a soil, soil moisture, and soil O2 levels.

  8. Analysis of vocal and swallowing functions after horizontal glottectomy.

    PubMed

    Topaloğlu, İlhan; Bal, Muhlis; Salturk, Ziya; Berkiten, Güler; Atar, Yavuz

    2016-08-01

    We conducted a cross-sectional study to assess vocal and swallowing functions after horizontal glottectomy. Our study population was made up of 22 men aged 45 to 72 years (mean: 58.3) who underwent horizontal glottectomy and completed at least 1 year of follow-up. To compare postoperative results, 20 similarly aged men were included as a control group; all glottectomy patients and all controls were smokers. We used three methods-acoustic and aerodynamic voice analyses, the GRBAS (grade, roughness, breathiness, asthenicity, and strain) scale, and the voice handicap index-30 (VHI-30)-to assess vocal function objectively, perceptually, and subjectively, respectively. We also assessed swallowing function objectively by fiberoptic endoscopic evaluation of swallowing (FEES) and subjectively with the M.D. Anderson dysphagia inventory (MDADI). The 22 patients were also subcategorized into three groups according to the extent of their arytenoid cartilage resection, and their outcomes were compared. Acoustic and aerodynamic analyses showed that the mean maximum phonation time was significantly shorter and the fundamental frequency was significantly lower in the glottectomy group than in the controls (p = 0.001 for both), and that the mean jitter and shimmer values and the mean harmonics-to-noise ratio were all significantly higher (p = 0.001 for all); there were no significant differences among the three arytenoid subgroups. Self-assessments revealed that there were no statistically significant differences among the three subgroups in GRBAS scale scores except for the breathiness score (p = 0.045), which was lower in the arytenoid preservation subgroup than in the total resection subgroup; there were no statistically significant differences among the three subgroups in VHI-30 scores. Finally, swallow testing found no statistically significant differences in FEES scores or MDADI scores. We conclude that horizontal glottectomy caused a deterioration in vocal function, but

  9. Geophysical investigations in deep horizontal holes drilled ahead of tunnelling

    USGS Publications Warehouse

    Carroll, R.D.; Cunningham, M.J.

    1980-01-01

    Deep horizontal drill holes have been used since 1967 by the Defense Nuclear Agency as a primary exploration tool for siting nuclear events in tunnels at the Nevada Test Site. The U.S. Geological Survey had developed geophysical logging techniques for obtaining resistivity and velocity in these holes, and to date 33 horizontal drill holes in excess of 300 m in depth have been successfully logged. The deepest hole was drilled to a horizontal depth of 1125 m. The purposes of the logging measurements are to define clay zones, because of the unstable ground conditions such zones can present to tunnelling, and to define zones of partially saturated rock, because of the attenuating effects such zones have on the shock wave generated by the nuclear detonation. Excessive attenuation is undesirable because the shock wave is used as a tunnel closure mechanism to contain debris and other undesirable explosion products. Measurements are made by pumping resistivity, sonic and geophone probes down the drill string and out of the bit into the open hole. Clay zones are defined by the electrical resistivity technique based on empirical data relating the magnitude of the resistivity measurement to qualitative clay content. Rock exhibiting resistivity of less than 20 ??-m is considered potentially unstable, and resistivities less than 10 ??-m indicate appreciable amounts of clay are present in the rock. Partially saturated rock zones are defined by the measurement of the rock sound speed. Zones in the rock which exhibit velocities less than 2450 m/sec are considered of potential concern. ?? 1980.

  10. SAW convolvers using the transverse-horizontal bilinear field

    NASA Astrophysics Data System (ADS)

    Monks, T.; Paige, E. G. S.; Woods, R. C.

    1983-06-01

    The surface-acoustic-wave (SAW) convolver provides a means of achieving high time-bandwidth, programmable signal processing. The operation of most SAW convolver designs has been based on the detection of an electric-polarization field normal to the crystal surface. The field arises from the mixing of two counter-propagating surface-acoustic waves. The present investigation is concerned with a new type of convolver which is based on the detection of the bilinear electric polarization parallel to the crystal surface and to the input wave-front. The new device is called a transverse-horizontal convolver (THC). A new electrode arrangement is needed to detect the polarization.

  11. Effect of occlusion, directionality and age on horizontal localization

    NASA Astrophysics Data System (ADS)

    Alworth, Lynzee Nicole

    Localization acuity of a given listener is dependent upon the ability discriminate between interaural time and level disparities. Interaural time differences are encoded by low frequency information whereas interaural level differences are encoded by high frequency information. Much research has examined effects of hearing aid microphone technologies and occlusion separately and prior studies have not evaluated age as a factor in localization acuity. Open-fit hearing instruments provide new earmold technologies and varying microphone capabilities; however, these instruments have yet to be evaluated with regard to horizontal localization acuity. Thus, the purpose of this study is to examine the effects of microphone configuration, type of dome in open-fit hearing instruments, and age on the horizontal localization ability of a given listener. Thirty adults participated in this study and were grouped based upon hearing sensitivity and age (young normal hearing, >50 years normal hearing, >50 hearing impaired). Each normal hearing participant completed one localization experiment (unaided/unamplified) where they listened to the stimulus "Baseball" and selected the point of origin. Hearing impaired listeners were fit with the same two receiver-in-the-ear hearing aids and same dome types, thus controlling for microphone technologies, type of dome, and fitting between trials. Hearing impaired listeners completed a total of 7 localization experiments (unaided/unamplified; open dome: omnidirectional, adaptive directional, fixed directional; micromold: omnidirectional, adaptive directional, fixed directional). Overall, results of this study indicate that age significantly affects horizontal localization ability as younger adult listeners with normal hearing made significantly fewer localization errors than older adult listeners with normal hearing. Also, results revealed a significant difference in performance between dome type; however, upon further examination was not

  12. Frequency of encounter of aircraft in a random horizontal field

    NASA Technical Reports Server (NTRS)

    Bird, J. D.; Smith, K. A.

    1976-01-01

    Calculations were made of the frequency of encounter as a function of azimuth of encounter of a passing aircraft with the aircraft in a random planar horizontal field. All the field aircraft moved at a constant speed but in random directions. These calculations included the total frequency of encounter with the aircraft of the field and the frequency of encounter with those aircraft of the field which were encountered in the fore quadrant, in the lateral quadrants, and in the rear quadrant; the calculations were made for various speed ratios of the field aircraft and the passing aircraft.

  13. Numerical simulation of internal waves past a horizontal strip

    NASA Astrophysics Data System (ADS)

    Riahi Khalloufi, Mahmoud; Houcine, Hatem; Fraunié, Philippe; Chashechkin, Yuli; Redondo, Jose Manuel; Gharvi, Adel

    2016-04-01

    A numerical model for stratified flows has been developed and validated from laboratory experiments performed in a salty water channel at low Reynolds number, exhibiting reasonable agreement with data of Schlieren visualization, density marker and probe measurements of internal wave fields. In continuation to previous work concerning a vertical strip towed in a channel, new numerical results are presented for the more delicate case of horizontal plate. These results are discussed concerning theoretical approaches including singular components and observations in atmosphere and ocean. Acknowledgements : This research was supported by the Modtercom project of Region PACA, and the Laboratoire Mixte International COSYS-MED.

  14. Productivity improvement by frontier horizontal drilling in Italy

    SciTech Connect

    Schenato, A.

    1995-12-31

    Italian domestic activity on horizontal wells has been specially addressed to carbonate reservoir and specifically targeted to re-entry in existing wells. The speech will focus on the specific experience matured in frontier applications in Italy, from 1989 with the short radius drain holes in Sicily, throughout world record deep water short radius in the southern part of Adriatic sea and depth world record medium radius in a HP/HT reservoir in the Po Valley. Production results will be reported as well as the achieved technological aspects.

  15. Italian river crossing; Horizontal drilling meets pipeline project criteria

    SciTech Connect

    Not Available

    1988-06-01

    The River Piave flows out of the Italian Alps, crossing the Veneto farmlands on its way to the Adriatic Sea. It is an important commerce-carrying waterway. SNAM, the Italian state gas pipeline company, wanted to install a 22-in. pipeline across the Piave just north of Venice. The method chosen for crossing the river had to meet several important criteria. InArc had used its river crossing method on seven previous SNAM projects and recommended the Piave crossing should be drilled. This paper describes the use of this horizontal drilling method for this application.

  16. Smoldering combustion propagation through a permeable horizontal fuel layer

    SciTech Connect

    Ohlemiller, T.J. )

    1990-09-01

    Although the propagation rate of smoldering through porous horizontal fuel layers has been measured for a variety of materials, there has been little work on the structure of the smolder reaction zone and the factors controlling it. These latter aspects are the focus for this paper for the case of thick (18 cm) layers of wood-based fibers in the form of cellulosic insulation smoldering under natural convection air supply conditions. Two-dimensional profiles of temperature, oxygen mole fraction, and residual organic material have been measured both for unretarded insulation and for insulation having 25 wt% of the smolder retardant, boric acid, added on.

  17. Frontogenesis driven by horizontally quadratic distributions of density

    NASA Technical Reports Server (NTRS)

    Jacqmin, David

    1991-01-01

    Attention is given to the quadratic density distribution in a channel, which has been established by Simpson and Linden to be the simplest case of the horizontally nonlinear distribution of fluid density required for the production of frontogenesis. The porous-media and Boussinesq flow models are examined, and their evolution equations are reduced to one-dimensional systems. While both the porous-media and the inviscid/nondiffusive Boussinesq systems exhibit classic frontogenesis behavior, the viscous Boussinesq system exhibits a more complex behavior: boundary-layer effects force frontogenesis away from the lower boundary, and at late times the steepest density gradients are close to mid-channel.

  18. Convection in a colloidal suspension in a closed horizontal cell

    SciTech Connect

    Smorodin, B. L. Cherepanov, I. N.

    2015-02-15

    The experimentally detected [1] oscillatory regimes of convection in a colloidal suspension of nanoparticles with a large anomalous thermal diffusivity in a closed horizontal cell heated from below have been simulated numerically. The concentration inhomogeneity near the vertical cavity boundaries arising from the interaction of thermal-diffusion separation and convective mixing has been proven to serve as a source of oscillatory regimes (traveling waves). The dependence of the Rayleigh number at the boundary of existence of the traveling-wave regime on the aspect ratio of the closed cavity has been established. The spatial characteristics of the emerging traveling waves have been determined.

  19. ENDOSYMBIOTIC AND HORIZONTAL GENE TRANSFER IN CHROMALVEOLATES(1).

    PubMed

    Bhattacharya, Debashish; Nosenko, Tetyana

    2008-02-01

    Chromalveolates include photosynthetic and nonphotosynthetic (some plastid-lacking) algae and protists that define a vast swath of eukaryotic diversity. These taxa are masters of gene acquisition through serial endosymbiosis (endosymbiotic gene transfer, EGT) and horizontal gene transfer (HGT). Understanding the contribution of these sources to nuclear genomes is key to elucidating chromalveolate evolution and to identifying suitable phylogenetic markers to place this lineage in the tree of life. Here we briefly review recent findings in our lab with regard to EGT and HGT in chromalveolates.

  20. Detection of Steps in Single Molecule Data

    PubMed Central

    Aggarwal, Tanuj; Materassi, Donatello; Davison, Robert; Hays, Thomas; Salapaka, Murti

    2013-01-01

    Over the past few decades, single molecule investigations employing optical tweezers, AFM and TIRF microscopy have revealed that molecular behaviors are typically characterized by discrete steps or events that follow changes in protein conformation. These events, that manifest as steps or jumps, are short-lived transitions between otherwise more stable molecular states. A major limiting factor in determining the size and timing of the steps is the noise introduced by the measurement system. To address this impediment to the analysis of single molecule behaviors, step detection algorithms incorporate large records of data and provide objective analysis. However, existing algorithms are mostly based on heuristics that are not reliable and lack objectivity. Most of these step detection methods require the user to supply parameters that inform the search for steps. They work well, only when the signal to noise ratio (SNR) is high and stepping speed is low. In this report, we have developed a novel step detection method that performs an objective analysis on the data without input parameters, and based only on the noise statistics. The noise levels and characteristics can be estimated from the data providing reliable results for much smaller SNR and higher stepping speeds. An iterative learning process drives the optimization of step-size distributions for data that has unimodal step-size distribution, and produces extremely low false positive outcomes and high accuracy in finding true steps. Our novel methodology, also uniquely incorporates compensation for the smoothing affects of probe dynamics. A mechanical measurement probe typically takes a finite time to respond to step changes, and when steps occur faster than the probe response time, the sharp step transitions are smoothed out and can obscure the step events. To address probe dynamics we accept a model for the dynamic behavior of the probe and invert it to reveal the steps. No other existing method addresses

  1. About the horizontal variability of effective radius in stratocumulus clouds

    NASA Astrophysics Data System (ADS)

    Magaritz-Ronen, L.; Khain, A.; Pinsky, M.

    2016-08-01

    The role of turbulent mixing in formation of low horizontal variability of effective radius near the top of nondrizzling stratocumulus clouds is investigated in simulations of clouds observed during the Second Dynamics and Chemistry of Marine Stratocumulus field experiment. The clouds are simulated using a spectral bin microphysics Lagrangian-Eulerian model consisting of ~2000 adjacent parcels moving in a turbulence-like field with observed correlation properties. The parcels interact through drop sedimentation and turbulent mixing. It was found that the effective radius variability in the horizontal direction near cloud top does not exceed ~10% of the averaged value. Three different types of cloud parcels are revealed to be differently influenced by mixing: ascending slightly diluted parcels, cloudy parcels experiencing intense mixing with parcels from inversion, and initially dry parcels. The evolution of droplet size distributions in parcels belonging to these types is investigated. It is shown that in parcels of the first two types the values of effective radii do not change or change only slightly remaining close to the adiabatic value. In initially droplet-free parcels effective radius rapidly reaches a value close to the adiabatic value, while liquid water content remains low. Therefore, turbulent mixing leads to establishing vertical profiles of effective radius, which are close to the adiabatic profile.

  2. Adaptive Horizontal Gene Transfers between Multiple Cheese-Associated Fungi.

    PubMed

    Ropars, Jeanne; Rodríguez de la Vega, Ricardo C; López-Villavicencio, Manuela; Gouzy, Jérôme; Sallet, Erika; Dumas, Émilie; Lacoste, Sandrine; Debuchy, Robert; Dupont, Joëlle; Branca, Antoine; Giraud, Tatiana

    2015-10-01

    Domestication is an excellent model for studies of adaptation because it involves recent and strong selection on a few, identified traits [1-5]. Few studies have focused on the domestication of fungi, with notable exceptions [6-11], despite their importance to bioindustry [12] and to a general understanding of adaptation in eukaryotes [5]. Penicillium fungi are ubiquitous molds among which two distantly related species have been independently selected for cheese making-P. roqueforti for blue cheeses like Roquefort and P. camemberti for soft cheeses like Camembert. The selected traits include morphology, aromatic profile, lipolytic and proteolytic activities, and ability to grow at low temperatures, in a matrix containing bacterial and fungal competitors [13-15]. By comparing the genomes of ten Penicillium species, we show that adaptation to cheese was associated with multiple recent horizontal transfers of large genomic regions carrying crucial metabolic genes. We identified seven horizontally transferred regions (HTRs) spanning more than 10 kb each, flanked by specific transposable elements, and displaying nearly 100% identity between distant Penicillium species. Two HTRs carried genes with functions involved in the utilization of cheese nutrients or competition and were found nearly identical in multiple strains and species of cheese-associated Penicillium fungi, indicating recent selective sweeps; they were experimentally associated with faster growth and greater competitiveness on cheese and contained genes highly expressed in the early stage of cheese maturation. These findings have industrial and food safety implications and improve our understanding of the processes of adaptation to rapid environmental changes.

  3. Horizontal pumping system installed at East Texas gas plant

    SciTech Connect

    Lopez, M.; Goodwin, B.

    1998-07-20

    Installation of horizontal, multistage centrifugal pumps in lean-amine service has proven successful and economical at Union Pacific Resources (UPR) East Texas gas plant (ETGP), Carthage, Tex. In the past, UPR had used either vertical can pumps or positive displacement (PD) pumps for amine circulation in gas-treating operations. When the need to replace a PD pump in the No. 4 amine plant arose, UPR solicited bids from both traditional pump suppliers. Additionally, UPR solicited a bid from REDA for its horizontal pumping system (HPS) based on previous success of this type of pump at ETGP for saltwater disposal. The first pump was installed in May 1996 and designed to circulate a maximum of 80 gpm. Since installation of the pump in No. 4 amine-treating unit, UPR has experienced no downtime and realized a significant cost savings on maintenance labor and parts over the previous positive displacement installation. The success of this HPS in amine service has led UPR to invest in five additional HPS pumps for ETGP`s amine service. The paper describes the decision, economics, pumping systems, preventive maintenance, and post installation performance.

  4. Horizontal Strain Field for the Bohemian Massif, Central Europe

    NASA Astrophysics Data System (ADS)

    Schenk, V.; Pichl, R.; Schenkova, Z.; Marek, T.

    2010-12-01

    The horizontal strain field of the Bohemian Massif, central Europe, was assessed from GNSS data monitored on permanent stations of the Geodynamic Network of the Academy of Science of the Czech Republic (GEONAS) and of the Czech Office for Surveying, Mapping and Cadastre (CZEPOS). For every area a representative motion velocity was determined. Their comparison with general motions of the Eurasian plate ascertained by the NNR-NUVEL-1A model gave deviations characterizing recent influence of the Alps to the northern geological units, in our case the Bohemian Massif. From these motions a regional pattern of the horizontal strain field for the Bohemian Massif had been calculated. It was found that (i) the northern part of the Massif is under dominant E-W extensions and (ii) slight contractions were detected for the NNE-SSW direction in eastern regions of the Massif. Obtained results will be presented and discussed from a viewpoint of the Alpine structural unit actions to surrounding geological units.

  5. Horizontal Transfer of Spinosad in Coptotermes formosanus (Isoptera: Rhinotermitidae).

    PubMed

    Bhatta, D; Henderson, G

    2016-08-01

    Slow-acting and nonrepellent termiticides are possible candidates for nestmate to nestmate transfer called horizontal transfer. For the horizontal transfer study of spinosad, Coptotermes formosanus Shiraki was released in sand and soil at 1, 25, and 50 ppm Entrust(®) for 1 h and then mixed with healthy untreated termites for 21 d at the ratio of 1:1. Donor and recipient termites began to contact and groom each other immediately after release. Mortality of termites was recorded at 1, 3, 7, and 14 d after treatment. Spinosad was more effectively transferred in sand than in soil. In sand at 25 and 50 ppm, significantly high mortality of donors and recipients was observed after 7 d. When termites were exposed to treated soil at day 21, all three concentrations resulted in significantly higher mortality compared to the control. In our laboratory study, spinosad was effectively transferred by donor termites. Transfer of spinosad depended on its bioavailability and concentration. Further study is needed to address its effects against C. formosanus under field conditions.

  6. Crosswell Imaging Technology & Advanced DSR Navigation for Horizontal Directional Drilling

    SciTech Connect

    Larry Stolarczyk

    2008-08-08

    The objective of Phase II is to develop and demonstrate real-time measurement-while-drilling (MWD) for guidance and navigation of drill strings during horizontal drilling operations applicable to both short and long holes. The end product of Phase II is a functional drill-string assembly outfitted with a commercial version of Drill String Radar (DSR). Project Objectives Develop and demonstrate a dual-phase methodology of in-seam drilling, imaging, and structure confirmation. This methodology, illustrated in Figure 1, includes: (1) Using RIM to image between drill holes for seam thickness estimates and in-seam structures detection. Completed, February 2005; and (2) Using DSR for real-time MWD guidance and navigation of drillstrings during horizontal drilling operations. Completed, November 2008. As of November 2008, the Phase II portion of Contract DE-FC26-04NT42085 is about 99% complete, including milestones and tasks original outlined as Phase II work. The one percent deficiency results from MSHA-related approvals which have yet to be granted (at the time of reporting). These approvals are pending and are do not negatively impact the scope of work or project objectives.

  7. Intraradicular Splinting with Endodontic Instrument of Horizontal Root Fracture

    PubMed Central

    Çiçek, Ersan; Yılmaz, Neslihan; Koçak, Mustafa Murat

    2015-01-01

    Introduction. Root fractures, defined as fractures involving dentine, cementum, and pulpal and supportive tissues, constitute only 0.5–7% of all dental injuries. Horizontal root fractures are commonly observed in the maxillary anterior region and 75% of these fractures occur in the maxillary central incisors. Methods. A 14-year-old female patient was referred to our clinic three days after a traffic accident. In radiographic examination, the right maxillary central incisor was fractured horizontally in apical thirds. Initially, following local infiltrative anesthetics, the coronal fragment was repositioned and this was radiographically confirmed. Then the stabilization splint was applied and remained for three months. After three weeks, according to the results of the vitality tests, the right and left central incisors were nonvital. For the right central incisor, both the coronal and apical fragments were involved in the endodontic preparation. Results. For the right central tooth, both the coronal and apical root fragments were endodontically treated and obturated at a single visit with white mineral trioxide aggregate whilst the fragments were stabilized internally by insertion of a size 40 Hedstrom stainless-steel endodontic file into the canal. Conclusion. Four-year follow-up examination revealed satisfactory clinical and radiographic findings with hard tissue repair of the fracture line. PMID:25648395

  8. Experimental consequences of a horizontal gauge model for CP nonconservation

    SciTech Connect

    Hou, W.; Soni, A.

    1985-05-13

    The experimental consequences of a model that links CP nonconservation with horizontal interactions and is based on the gauge group SU/sub l//sup W/(2) x SU/sub R//sup H/(2) x U/sup Y/ (1) are investigated. The magnitude of the observed CP nonconservation and that of the K/sub L/-K/sub S/ mass difference constrains the horizontal gauge boson masses (M/sub s/crR) such that 66 TeV> or approx. =M/sub s/crR>5 TeV. The model implies an extremely small value for Vertical Barepsilon'/epsilonVertical Bar. The branching ratio for K/sub L/..--> mu..e (K..--> pi mu..e) could be greater than roughly-equal10/sup -10/ (approx.10/sup -12/). theta/sub QFD/ vanishes at the tree level. The contribution from the gauge sector, arising at two loops, is also discussed.

  9. Design guidelines and procedures for guided horizontal drilling

    SciTech Connect

    Kirby, M.J.; Kramer, S.R.; Pittard, G.T.; Mamoun, M.

    1996-08-01

    Jason Consultants International, Inc., under the sponsorship of the Gas Research Institute (GRI), has developed guidelines, procedures and software, which are described in this paper, for the installation of polyethylene gas pipe using guided horizontal drilling. Jason was aided in this development by two key subcontractors; Maurer Engineering who wrote the software and NICOR Technologies who reviewed the software and guidelines from a utility perspective. This program resulted in the development of commerically viable software for utilities, contractors, engineering firms, and others involved with the installation of pipes using guided horizontal drilling. The software is an interactive design tool that allows the user to enter ground elevation data, alignment information and pipe data. The software aides the engineer in designing a drill path and provides plan and profile views along with tabular data for pipe depth and surface profile. Finally, the software calculates installation loads and pipe stresses, compares these values against pipe manufacturer`s recommendations, and provides this information graphically and in tabular form. 5 refs., 18 figs., 2 tabs.

  10. Abundances in A-type Horizontal Branch Stars

    NASA Astrophysics Data System (ADS)

    Wilhelm, R.; Smith, V. V.

    1998-12-01

    As part of a program to explore correlations between abundance anomilies and physical parameters (e.g. Teff, vsini) in horizontal branch stars, we present preliminary results from high-resolution (R ~ 18,000) spectral observations of a small sample of A-type, horizontal branch stars. The sample was obtained using the 2.1m telescope and Sandiford Echelle at McDonald Observatory. A total of six standard FHB stars were observed including two, HD 130095 and HD 167105, which have been previously shown by Adleman and Philip to posses anomalously low [Ca/Fe] values. We have also obtained observations of eight of the brighter (B = 11.5-12.5) FHB stars from the HK objective-prism survey and two BHB stars from the globular cluster, M4. We will present abundance results that include [Ca/Fe], [Mg/Fe], and vsini values for the sample along with O and Na results for the two M4 stars. Our findings will be compared to previously published results for cluster BHB and field HB stars.

  11. Horizontal Path Laser Communications Employing MEMS Adaptive Optics Correction

    SciTech Connect

    Thompson, C A; Wilks, S C; Brase, J M; Young, R A; Johnson, G W; Ruggiero, A J

    2001-09-05

    Horizontal path laser communications are beginning to provide attractive alternatives for high-speed optical communications, In particular, companies are beginning to sell fiberless alternatives for intranet and sporting event video. These applications are primarily aimed at short distance applications (on the order of 1 km pathlength). There exists a potential need to extend this pathlength to distances much greater than a 1km. For cases of long distance optical propagation, atmospheric turbulence will ultimately limit the maximum achievable data rate. In this paper, we propose a method of improved signal quality through the use of adaptive optics. In particular, we show work in progress toward a high-speed, small footprint Adaptive Optics system for horizontal path laser communications. Such a system relies heavily on recent progress in Micro-Electro-Mechanical Systems (MEMS) deformable mirrors as well as improved communication and computational components. In this paper we detail two Adaptive Optics approaches for improved through-put, the first is the compensated receiver (the traditional Adaptive Optics approach), the second is the compensated transmitter/receiver. The second approach allows for correction of the optical wavefront before transmission from the transmitter and prior to detection at the receiver.

  12. Analysis of horizontal flows in the solar granulation

    NASA Astrophysics Data System (ADS)

    Quintero Noda, C.; Shimizu, T.; Suematsu, Y.

    2016-04-01

    Solar limb observations sometimes reveal the presence of a satellite lobe in the blue wing of the Stokes I profile from pixels belonging to granules. The presence of this satellite lobe has been associated in the past to strong line-of-sight gradients and, as the line-of-sight component is almost parallel to the solar surface, to horizontal granular flows. We aim to increase the knowledge about these horizontal flows studying a spectropolarimetric observation of the north solar pole. We will make use of two state of the art techniques, the spatial deconvolution procedure that increases the quality of the data removing the stray light contamination, and spectropolarimetric inversions that will provide the vertical stratification of the atmospheric physical parameters where the observed spectral lines form. We inverted the Stokes profiles using a two component configuration, obtaining that one component is strongly blueshifted and displays a temperature enhancement at upper photospheric layers while the second component has low redshifted velocities and it is cool at upper layers. In addition, we examined a large number of cases located at different heliocentric angles, finding smaller velocities as we move from the centre to the edge of the granule. Moreover, the height location of the enhancement on the temperature stratification of the blueshifted component also evolves with the spatial location on the granule being positioned on lower heights as we move to the periphery of the granular structure.

  13. Adjustable recessions in horizontal comitant strabismus: A pilot study

    PubMed Central

    Agrawal, Siddharth; Singh, Vinita; Singh, Priyanka

    2015-01-01

    Aim: To compare the surgical outcome of adjustable with the conventional recession in patients with horizontal comitant strabismus. Patients and Methods: A prospective comparative nonrandomized interventional pilot study was performed on patients with horizontal comitant strabismus. Fifty-four patients (27 in each group) were allocated into 2 groups to undergo either adjustable suture (AS) recession or non-AS (NAS) recession along with conventional resection. The patients were followed up for 6 months. A successful outcome was defined as deviation ±10 prism diopters at 6 months. The results were statistically analyzed by Chi-square test, Fisher's exact test, and Student's t-test. Results: A successful outcome was found in 24 (88.8%) patients in AS and 17 (62.9%) in NAS group (P = 0.02). The postoperative adjustment was done in 13 (48.1%) patients in AS group. There was one complication (tenon's cyst) in AS group. Conclusion: AS recession may be considered in all cooperative patients undergoing strabismus surgery for comitant deviations. PMID:26458480

  14. Anisoplanatic Performance of Horizontal-Path Speckle Imaging

    SciTech Connect

    Carrano, C J

    2003-07-01

    We have previously demonstrated and reported on the use of sub-field speckle processing for the enhancement of both near and far-range surveillance imagery of people and vehicles that have been degraded by atmospheric turbulence. We have obtained near diffraction-limited imagery in many cases and have shown dramatic image quality improvement in other cases. As it is possible to perform only a limited number of experiments in a limited number of conditions, we have developed a computer simulation capability to aid in the prediction of imaging performance in a wider variation of conditions. Our simulation capability includes the ability to model extended scenes in distributed turbulence. Of great interest is the effect of the isoplanatic angle on speckle imaging performance as well as on single deformable mirror and multiconjugate adaptive optics system performance. These angles are typically quite small over horizontal and slant paths. This paper will begin to explore these issues which are important for predicting the performance of both passive and active horizontal and slant-path imaging systems.

  15. Horizontal-axis clothes washer market poised for expansion

    SciTech Connect

    George, K.L.

    1994-12-31

    The availability of energy- and water-efficient horizontal-axis washing machines in the North American market is growing, as US and European manufacturers position for an expected long-term market shift toward horizontal-axis (H-axis) technology. Four of the five major producers of washing machines in the US are developing or considering new H-axis models. New entrants, including US-based Staber Industries and several European manufacturers, are also expected to compete in this market. The intensified interest in H-axis technology is partly driven by speculation that new US energy efficiency standards, to be proposed in 1996 and implemented in 1999, will effectively mandate H-axis machines. H-axis washers typically use one-third to two-thirds less energy, water, and detergent than vertical-axis machines. Some models also reduce the energy needed to dry the laundry, since their higher spin speeds extract more water than is typical with vertical-axis designs. H-axis washing machines are the focus of two broadly-based efforts to support coordinated research and incentive programs by electric, gas, and water utilities: The High-Efficiency Laundry Metering/Marketing Analysis (THELMA), and the Consortium for Energy Efficiency (CEE) High-Efficiency Clothes Washer Initiative. These efforts may help to pave the way for new types of marketing partnerships among utilities and other parties that could help to speed adoption of H-axis washers.

  16. Aeroelastic stability and response of horizontal axis wind turbine blades

    NASA Technical Reports Server (NTRS)

    Kottapalli, S. B. R.; Friedmann, P. P.; Rosen, A.

    1978-01-01

    The coupled flap-lag-torsion equations of motion of an isolated horizontal axis wind turbine blade are formulated. Quasi-steady blade-element strip theory was applied to derive the aerodynamic operator which includes boundary layer type gradient winds. The final equations which have periodic coefficients were solved in order to obtain the aeroelastic response and stability of large horizontal axis wind turbine blade. A new method of generating an appropriate time-dependent equilibrium position (required for the stability analysis) has been implemented. Representative steady-state responses and stability boundaries, applicable mainly to an existing blade design (NASA/-ERDA MOD-0), are presented. The results indicate that the MOD-0 configuration is a basically stable design and that blade stability is not sensitive to offsets between blade elastic axis and aerodynamic center. Blade stability appears to be sensitive to precone. The tower shadow (or wake) has a considerable effect on the flap response but leaves blade stability unchanged. Finally, it was found that non linear terms in the equations of motion can significantly affect the linearized stability boundaries, however, these terms have a negligible effect on blade response at operating conditions.

  17. Horizontal Transfer of Spinosad in Coptotermes formosanus (Isoptera: Rhinotermitidae).

    PubMed

    Bhatta, D; Henderson, G

    2016-08-01

    Slow-acting and nonrepellent termiticides are possible candidates for nestmate to nestmate transfer called horizontal transfer. For the horizontal transfer study of spinosad, Coptotermes formosanus Shiraki was released in sand and soil at 1, 25, and 50 ppm Entrust(®) for 1 h and then mixed with healthy untreated termites for 21 d at the ratio of 1:1. Donor and recipient termites began to contact and groom each other immediately after release. Mortality of termites was recorded at 1, 3, 7, and 14 d after treatment. Spinosad was more effectively transferred in sand than in soil. In sand at 25 and 50 ppm, significantly high mortality of donors and recipients was observed after 7 d. When termites were exposed to treated soil at day 21, all three concentrations resulted in significantly higher mortality compared to the control. In our laboratory study, spinosad was effectively transferred by donor termites. Transfer of spinosad depended on its bioavailability and concentration. Further study is needed to address its effects against C. formosanus under field conditions. PMID:27207263

  18. Quasi-horizontal circulation cells in 3D seawater intrusion

    USGS Publications Warehouse

    Abarca, E.; Carrera, J.; Sanchez-Vila, X.; Voss, C.I.

    2007-01-01

    The seawater intrusion process is characterized by the difference in freshwater and seawater density that causes freshwater to float on seawater. Many confined aquifers have a large horizontal extension with respect to thickness. In these cases, while buoyancy acts in the vertical direction, flow is confined between the upper and bottom boundaries and the effect of gravity is controlled by variations of aquifer elevation. Therefore, the effective gravity is controlled by the slope and the shape of the aquifer boundaries. Variability in the topography of the aquifer boundaries is one case where 3D analysis is necessary. In this work, density-dependent flow processes caused by 3D aquifer geometry are studied numerically and specifically, considering a lateral slope of the aquifer boundaries. Sub-horizontal circulation cells are formed in the saltwater entering the aquifer. The penetration of the saltwater can be quantified by a dimensionless buoyancy number that measures the lateral slope of the aquifer relative to freshwater flux. The penetration of the seawater intrusion wedge is controlled more by this slope than by the aquifer thickness and dispersivity. Thus, the slope must be taken into account in order to accurately evaluate seawater intrusion. ?? 2007 Elsevier B.V. All rights reserved.

  19. Experimental and numerical investigation of the horizontal ribbon growth process

    NASA Astrophysics Data System (ADS)

    Helenbrook, Brian T.; Kellerman, Peter; Carlson, Frederick; Desai, Nandish; Sun, Dawei

    2016-11-01

    Experimental and numerical results are presented on the process of horizontal ribbon growth (HRG) of single-crystal silicon. Experimental data on the leading edge position of the growth front as a function of pull speed is compared to model predictions with and without solidification kinetic effects. Without kinetics, the numerical results predict leading edge positions which are completely different than that observed in the experiment. With kinetics, the leading edge position is predicted typically within 1 mm and the change in position with pull speed also is well predicted. Conclusions from the kinetic model are that the growth occurs through a faceted process where the leading edge is a {111} facet that requires significant supercooling to maintain the growth. An outcome of the model is that the leading edge position versus pull speed response shows a turning point beyond which there are no steady growth solutions. This is consistent with all previously reported experiments on this process, which have reported maximum attainable pull-speeds. These results directly contradict previous conclusions from the "wedge" model of horizontal ribbon growth, which predicts that a large area wedge-shaped growth region exists and that increasing pull speeds simply result in a narrower wedge angle.

  20. Model for sweet corrosion in horizontal multiphase slug flow

    SciTech Connect

    Jepson, W.P.; Stitzel, S.; Kang, C.; Gopal, M.

    1997-08-01

    A model has been developed that can predict the corrosion rate in horizontal slug flows. The effect of the slug frequency and oil type on corrosion rate have been included. The model has been compared to experimental data, and, to the model and field data of Gunaltun (1996). For all conditions, the corrosion rate increased with increase in slug frequency until a maximum in corrosion rate is reached at approximately 35 slugs/minute. At 60 C, the model compares well with that of Gunaltun (1996) if a slug frequency of 10 to 12 is used. For 80 C, the Gunaltun model is in good agreement if a frequency of 1 slug/minute is used. His model does not include a term that predicts a maximum in the corrosion rate between 60 and 80 C. This has not been noticed in this laboratory for slug flows. For horizontal pipelines, field data suggests that, the slug frequency is usually in the range of 1 to 20 slugs/minute, depending on the liquid velocity. When the pipe is inclined, the slug frequency can increase to values much greater than these and this may lead to higher levels of corrosion. The oil type is accounted for using the suggestion of Efird (1989) based on the product of oil acid number and % nitrogen. When this relation is used, the results compare very well with those of Efird for the oils he studied.

  1. Horizontal gene transfer and mobile genetic elements in marine systems.

    PubMed

    Sobecky, Patricia A; Hazen, Tracy H

    2009-01-01

    The pool of mobile genetic elements (MGE) in microbial communities consists of viruses, plasmids, and associated elements (insertion sequences, transposons, and integrons) that are either self-transmissible or use mobile plasmids and viruses as vehicles for their dissemination. This mobilome facilitates the horizontal transfer of genes that promote the evolution and adaptation of microbial communities. Efforts to characterize MGEs from microbial populations resident in a variety of ecological habitats have revealed a surprisingly novel and seemingly untapped biodiversity. To better understand the impact of horizontal gene transfer (HGT), as well as the agents that promote HGT in marine ecosystems and to determine whether or not environmental parameters can effect the composition and structure of the mobilome in marine microbial communities, information on the distribution, diversity, and ecological traits of the marine mobilome is presented. In this chapter we discuss recent insights gained from different methodological approaches used to characterize the biodiversity and ecology of MGE in marine environments and their contributions to HGT. In addition, we present case studies that highlight specific HGT examples in coastal, open-ocean, and deep-sea marine ecosystems.

  2. Vibrational stability of a cryocooled horizontal double-crystal monochromator.

    PubMed

    Kristiansen, Paw; Johansson, Ulf; Ursby, Thomas; Jensen, Brian Norsk

    2016-09-01

    The vibrational stability of a horizontally deflecting double-crystal monochromator (HDCM) is investigated. Inherently a HDCM will preserve the vertical beam stability better than a `normal' vertical double-crystal monochromator as the vibrations of a HDCM will almost exclusively affect the horizontal stability. Here both the relative pitch vibration between the first and second crystal and the absolute pitch vibration of the second crystal are measured. All reported measurements are obtained under active cooling by means of flowing liquid nitrogen (LN2). It is found that it is favorable to circulate the LN2 at high pressures and low flow rates (up to 5.9 bar and down to 3 l min(-1) is tested) to attain low vibrations. An absolute pitch stability of the second crystal of 18 nrad RMS, 2-2500 Hz, and a relative pitch stability between the two crystals of 25 nrad RMS, 1-2500 Hz, is obtained under cryocooling conditions that allow for 1516 W to be adsorbed by the LN2 before it vaporizes. PMID:27577758

  3. Modelling of horizontal centrifugal casting of work roll

    NASA Astrophysics Data System (ADS)

    Xu, Zhian; Song, Nannan; Tol, Rob Val; Luan, Yikun; Li, Dianzhong

    2012-07-01

    A numerical model to simulate horizontal centrifugal roll castings is presented in this paper. In order to simulate the flow fluid and solidification of horizontal centrifugal roll casting correctly, the model uses a body fitted mesh technique to represent the geometry. This new method maps a plate layer mesh to a circular mesh. The smooth body fitted mesh method gives more accurate calculation results for cylindrical geometries. A velocity depending on the angular velocity and inner radius of the mould is set up as a velocity boundary condition. The fluid flow coupled with heat transfer and solidification in a rapidly rotating roll is simulated. A gravity free falling method is applied as a pouring condition. A moveable pouring system is also used in the simulations. High speed steel is used to produce the work roll. Two different gating positions and a moveable gating system are simulated in this paper. Results show that the position of pouring system has a significant influence on the temperature distribution. The temperature distribution at a fixed central pouring system is more favourable than the distribution from a side pouring system. A moving gating system method is a better way to obtain a uniform temperature field in centrifugal casting and offers an alternative for existing techniques.

  4. Torricelli's curtain: morphology of horizontal laminar jets under gravity

    NASA Astrophysics Data System (ADS)

    Ribe, Neil; Paternoster, Gabriel; Rabaud, Marc

    2012-11-01

    It has been ``known'' since the seventeenth century that a jet of water issuing horizontally from a hole in the side of a bucket describes a parabolic trajectory. However, this bit of canonical fluid mechanical lore is wrong in many cases. Our recent experiments performed on laminar jets issuing from a horizontal tube show that the initially round jet typically evolves into a thin vertical curtain bounded by bulbous rims at its upper and lower extremities. Moreover, injected dye reveals the presence of a recirculating flow with helical streamlines around the jet's axis. To understand this behavior, we formulate an analytical model for the near-orifice structure of the jet in the limit of large Froude number Fr ≡ɛ-1 >> 1 . We find that a recirculating flow is generated by the sinusoidal variation of the nonhydrostatic pressure around cross-sections of the jet at order ɛ, and that deformation of the cross-section occurs at order ɛ2. We also use the volume-of-fluid code Gerris to study numerically the evolution of the jet's morphology as a function of the Reynolds, Froude and Ohnesorge numbers, and compare the results with our analytical theory and with laboratory experiments.

  5. Vibrational stability of a cryocooled horizontal double-crystal monochromator

    PubMed Central

    Kristiansen, Paw; Johansson, Ulf; Ursby, Thomas; Jensen, Brian Norsk

    2016-01-01

    The vibrational stability of a horizontally deflecting double-crystal monochromator (HDCM) is investigated. Inherently a HDCM will preserve the vertical beam stability better than a ‘normal’ vertical double-crystal monochromator as the vibrations of a HDCM will almost exclusively affect the horizontal stability. Here both the relative pitch vibration between the first and second crystal and the absolute pitch vibration of the second crystal are measured. All reported measurements are obtained under active cooling by means of flowing liquid nitrogen (LN2). It is found that it is favorable to circulate the LN2 at high pressures and low flow rates (up to 5.9 bar and down to 3 l min−1 is tested) to attain low vibrations. An absolute pitch stability of the second crystal of 18 nrad RMS, 2–2500 Hz, and a relative pitch stability between the two crystals of 25 nrad RMS, 1–2500 Hz, is obtained under cryocooling conditions that allow for 1516 W to be adsorbed by the LN2 before it vaporizes. PMID:27577758

  6. Effects of Horizontal Magnetic Fields on Acoustic Travel Times

    NASA Astrophysics Data System (ADS)

    Jain, Rekha

    2007-02-01

    Local helioseismology techniques seek to probe the subsurface magnetic fields and flows by observing waves that emerge at the solar surface after passing through these inhomogeneities. Active regions on the surface of the Sun are distinguished by their strong magnetic fields, and techniques such as time-distance helioseismology can provide a useful diagnostic for probing these structures. Above the active regions, the fields fan out to create a horizontal magnetic canopy. We investigate the effect of a uniform horizontal magnetic field on the travel time of acoustic waves by considering vertical velocity in a simple plane-parallel adiabatically stratified polytrope. It is shown that such fields can lower the upper turning point of p-modes and hence influence their travel time. It is found that acoustic waves reflected from magnetically active regions have travel times up to a minute less than for waves similarly reflected in quiet regions. It is also found that sound speeds are increased below the active regions. These findings are consistent with time-distance measurements.

  7. Multi-mode reliability-based design of horizontal curves.

    PubMed

    Essa, Mohamed; Sayed, Tarek; Hussein, Mohamed

    2016-08-01

    Recently, reliability analysis has been advocated as an effective approach to account for uncertainty in the geometric design process and to evaluate the risk associated with a particular design. In this approach, a risk measure (e.g. probability of noncompliance) is calculated to represent the probability that a specific design would not meet standard requirements. The majority of previous applications of reliability analysis in geometric design focused on evaluating the probability of noncompliance for only one mode of noncompliance such as insufficient sight distance. However, in many design situations, more than one mode of noncompliance may be present (e.g. insufficient sight distance and vehicle skidding at horizontal curves). In these situations, utilizing a multi-mode reliability approach that considers more than one failure (noncompliance) mode is required. The main objective of this paper is to demonstrate the application of multi-mode (system) reliability analysis to the design of horizontal curves. The process is demonstrated by a case study of Sea-to-Sky Highway located between Vancouver and Whistler, in southern British Columbia, Canada. Two noncompliance modes were considered: insufficient sight distance and vehicle skidding. The results show the importance of accounting for several noncompliance modes in the reliability model. The system reliability concept could be used in future studies to calibrate the design of various design elements in order to achieve consistent safety levels based on all possible modes of noncompliance.

  8. Horizontal Borehole Flowmeter Evaluations in an Unconsolidated Aquifer Simulator

    NASA Astrophysics Data System (ADS)

    Bayless, E. R.

    2009-12-01

    Borehole flowmeters that measure horizontal flow velocity and direction of groundwater are being applied to a wide variety of environmental problems. This study was done to evaluate the measurement accuracy of several flowmeters. The flowmeters included a commercially available heat-pulse flowmeter, an acoustic Doppler flowmeter, a scanning colloidal borescope flowmeter, and a hydrophysical logging system. Measurements taken in an unconsolidated aquifer simulator tested flowmeter response to hydraulic gradient, aquifer properties and well-screen construction. Results of the study indicated that at least one flowmeter was capable of accurately measuring velocity and direction in most simulated conditions. Correction factors for differences between borehole and formation conditions were computed and generally fell within the theoretical ranges determined by previous investigations. The directional accuracy of all tested flowmeters improved with increasing hydraulic gradient. The accuracy of velocity measurements varied with well construction and simulator-velocity magnitude. The use of non-standard well construction methods and materials that maximize slot-opening area and control well-screen orientation may be preferred if flowmeter measurements are expected. The use of horizontal flowmeters in environmental studies appears promising but flowmeter applications may require more than one tool to measure the range of conditions encountered in the field.

  9. Horizontal Gene Transfer Contributes to the Evolution of Arthropod Herbivory

    PubMed Central

    Wybouw, Nicky; Pauchet, Yannick; Heckel, David G.; Van Leeuwen, Thomas

    2016-01-01

    Within animals, evolutionary transition toward herbivory is severely limited by the hostile characteristics of plants. Arthropods have nonetheless counteracted many nutritional and defensive barriers imposed by plants and are currently considered as the most successful animal herbivores in terrestrial ecosystems. We gather a body of evidence showing that genomes of various plant feeding insects and mites possess genes whose presence can only be explained by horizontal gene transfer (HGT). HGT is the asexual transmission of genetic information between reproductively isolated species. Although HGT is known to have great adaptive significance in prokaryotes, its impact on eukaryotic evolution remains obscure. Here, we show that laterally transferred genes into arthropods underpin many adaptations to phytophagy, including efficient assimilation and detoxification of plant produced metabolites. Horizontally acquired genes and the traits they encode often functionally diversify within arthropod recipients, enabling the colonization of more host plant species and organs. We demonstrate that HGT can drive metazoan evolution by uncovering its prominent role in the adaptations of arthropods to exploit plants. PMID:27307274

  10. Multi-mode reliability-based design of horizontal curves.

    PubMed

    Essa, Mohamed; Sayed, Tarek; Hussein, Mohamed

    2016-08-01

    Recently, reliability analysis has been advocated as an effective approach to account for uncertainty in the geometric design process and to evaluate the risk associated with a particular design. In this approach, a risk measure (e.g. probability of noncompliance) is calculated to represent the probability that a specific design would not meet standard requirements. The majority of previous applications of reliability analysis in geometric design focused on evaluating the probability of noncompliance for only one mode of noncompliance such as insufficient sight distance. However, in many design situations, more than one mode of noncompliance may be present (e.g. insufficient sight distance and vehicle skidding at horizontal curves). In these situations, utilizing a multi-mode reliability approach that considers more than one failure (noncompliance) mode is required. The main objective of this paper is to demonstrate the application of multi-mode (system) reliability analysis to the design of horizontal curves. The process is demonstrated by a case study of Sea-to-Sky Highway located between Vancouver and Whistler, in southern British Columbia, Canada. Two noncompliance modes were considered: insufficient sight distance and vehicle skidding. The results show the importance of accounting for several noncompliance modes in the reliability model. The system reliability concept could be used in future studies to calibrate the design of various design elements in order to achieve consistent safety levels based on all possible modes of noncompliance. PMID:27180287

  11. A horizontal vane radiometer: Experiment, theory, and simulation

    NASA Astrophysics Data System (ADS)

    Wolfe, David; Larraza, Andres; Garcia, Alejandro

    2016-03-01

    The existence of two motive forces on a Crookes radiometer has complicated the investigation of either force independently. The thermal creep shear force in particular has been subject to differing interpretations of the direction in which it acts and its order of magnitude. In this article, we provide a horizontal vane radiometer design which isolates the thermal creep shear force. The horizontal vane radiometer is explored through experiment, kinetic theory, and the Direct Simulation Monte Carlo (DSMC) method. The qualitative agreement between the three methods of investigation is good except for a dependence of the force on the width of the vane even when the temperature gradient is narrower than the vane which is present in the DSMC method results but not in the theory. The experimental results qualitatively resemble the theory in this regard. The quantitative agreement between the three methods of investigation is better than an order of magnitude in the cases examined. The theory is closer to the experimental values for narrow vanes and the simulations are closer to the experimental values for the wide vanes. We find that the thermal creep force acts from the hot side to the cold side of the vane. We also find the peak in the radiometer's angular speed as a function of pressure is explained as much by the behavior of the drag force as by the behavior of the thermal creep force.

  12. Using horizontal well technology for enhanced recovery in very mature, depletion drive gas reservoirs - Pirkle No. 2 well, a case history, carthage (Lower Pettit) field, Panola County, Texas

    SciTech Connect

    McCoy, A.W.; Davis, F.A.; Elrod, J.P.; Rhodes, S.L. Jr.; Singh, S.P.

    1996-12-31

    Horizontal well technology has been successfully applied to exploit reservoirs involving thin beds, low permeability zones, naturally fractured reservoirs, high-cost areas, and zones of water coning. The Pirkle No. 2 well represents the first use of horizontal technology to enhance ultimate gas recovery in a very mature, low pressure zone in the Lower Pettit horizon at Carthage Field, Panola County, Texas. The Pirkle No. 2 well was drilled to test the concept that a horizontal well could enhance ultimate recovery by lowering the final abandonment pressure in a very mature, depletion drive gas reservoir. However, numerous technical obstacles existed to the successful drilling and completion of an economic well in a 0.0308 psi/ft pressure gradient environment. This paper outlines the steps taken by OXY team members in planning and executing the project, as well as the results achieved from the Pirkle No. 2 well. Information gained from this project will help others to define appropriate screening criteria and provide dance for planning/application of horizontal technology to guide other mature gas reservoirs worldwide.

  13. Time scaling relations for step bunches from models with step-step attractions (B1-type models)

    NASA Astrophysics Data System (ADS)

    Krasteva, A.; Popova, H.; Akutsu, N.; Tonchev, V.

    2016-03-01

    The step bunching instability is studied in three models of step motion defined in terms of ordinary differential equations (ODE). The source of instability in these models is step-step attraction, it is opposed by step-step repulsion and the developing surface patterns reflect the balance between the two. The first model, TE2, is a generalization of the seminal model of Tersoff et al. (1995). The second one, LW2, is obtained from the model of Liu and Weeks (1998) using the repulsions term to construct the attractions one with retained possibility to change the parameters in the two independently. The third model, MM2, is a minimal one constructed ad hoc and in this article it plays a central role. New scheme for scaling the ODE in vicinal studies is applied towards deciphering the pre-factors in the time-scaling relations. In all these models the patterned surface is self-similar - only one length scale is necessary to describe its evolution (hence B1-type). The bunches form finite angles with the terraces. Integrating numerically the equations for step motion and changing systematically the parameters we obtain the overall dependence of time-scaling exponent β on the power of step-step attractions p as β = 1/(3+p) for MM2 and hypothesize based on restricted set of data that it is β = 1/(5+p) for LW2 and TE2.

  14. A Step-by-Step Teaching Technique for Teachers with Adult Students of Mathematics

    ERIC Educational Resources Information Center

    McDonald, Betty

    2013-01-01

    Step-by-step teaching is a researcher-designed innovative process that takes the adult learner, step-by-step, from his present level of understanding to the required level. The technique is based on well-researched and accepted pedagogical practices set in their psychological, sociological, and andragogical perspectives. Using a convenience sample…

  15. The upright posture improves plantar stepping and alters responses to serotonergic drugs in spinal rats

    PubMed Central

    Sławińska, Urszula; Majczyński, Henryk; Dai, Yue; Jordan, Larry M

    2012-01-01

    Recent studies on the restoration of locomotion after spinal cord injury have employed robotic means of positioning rats above a treadmill such that the animals are held in an upright posture and engage in bipedal locomotor activity. However, the impact of the upright posture alone, which alters hindlimb loading, an important variable in locomotor control, has not been examined. Here we compared the locomotor capabilities of chronic spinal rats when placed in the horizontal and upright postures. Hindlimb locomotor movements induced by exteroceptive stimulation (tail pinching) were monitored with video and EMG recordings. We found that the upright posture alone significantly improved plantar stepping. Locomotor trials using anaesthesia of the paws and air stepping demonstrated that the cutaneous receptors of the paws are responsible for the improved plantar stepping observed when the animals are placed in the upright posture. We also tested the effectiveness of serotonergic drugs that facilitate locomotor activity in spinal rats in both the horizontal and upright postures. Quipazine and (±)-8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OH-DPAT) improved locomotion in the horizontal posture but in the upright posture either interfered with or had no effect on plantar walking. Combined treatment with quipazine and 8-OH-DPAT at lower doses dramatically improved locomotor activity in both postures and mitigated the need to activate the locomotor CPG with exteroceptive stimulation. Our results suggest that afferent input from the paw facilitates the spinal CPG for locomotion. These potent effects of afferent input from the paw should be taken into account when interpreting the results obtained with rats in an upright posture and when designing interventions for restoration of locomotion after spinal cord injury. PMID:22351637

  16. The upright posture improves plantar stepping and alters responses to serotonergic drugs in spinal rats.

    PubMed

    Sławińska, Urszula; Majczyński, Henryk; Dai, Yue; Jordan, Larry M

    2012-04-01

    Recent studies on the restoration of locomotion after spinal cord injury have employed robotic means of positioning rats above a treadmill such that the animals are held in an upright posture and engage in bipedal locomotor activity. However, the impact of the upright posture alone, which alters hindlimb loading, an important variable in locomotor control, has not been examined. Here we compared the locomotor capabilities of chronic spinal rats when placed in the horizontal and upright postures. Hindlimb locomotor movements induced by exteroceptive stimulation (tail pinching) were monitored with video and EMG recordings. We found that the upright posture alone significantly improved plantar stepping. Locomotor trials using anaesthesia of the paws and air stepping demonstrated that the cutaneous receptors of the paws are responsible for the improved plantar stepping observed when the animals are placed in the upright posture.We also tested the effectiveness of serotonergic drugs that facilitate locomotor activity in spinal rats in both the horizontal and upright postures. Quipazine and (±)-8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OH-DPAT) improved locomotion in the horizontal posture but in the upright posture either interfered with or had no effect on plantar walking. Combined treatment with quipazine and 8-OH-DPAT at lower doses dramatically improved locomotor activity in both postures and mitigated the need to activate the locomotor CPG with exteroceptive stimulation. Our results suggest that afferent input from the paw facilitates the spinal CPG for locomotion. These potent effects of afferent input from the paw should be taken into account when interpreting the results obtained with rats in an upright posture and when designing interventions for restoration of locomotion after spinal cord injury.

  17. Control Circuit For Two Stepping Motors

    NASA Technical Reports Server (NTRS)

    Ratliff, Roger; Rehmann, Kenneth; Backus, Charles

    1990-01-01

    Control circuit operates two independent stepping motors, one at a time. Provides following operating features: After selected motor stepped to chosen position, power turned off to reduce dissipation; Includes two up/down counters that remember at which one of eight steps each motor set. For selected motor, step indicated by illumination of one of eight light-emitting diodes (LED's) in ring; Selected motor advanced one step at time or repeatedly at rate controlled; Motor current - 30 mA at 90 degree positions, 60 mA at 45 degree positions - indicated by high or low intensity of LED that serves as motor-current monitor; Power-on reset feature provides trouble-free starts; To maintain synchronism between control circuit and motors, stepping of counters inhibited when motor power turned off.

  18. A Versatile Step-Up/Step-Down Switched-Capacitor-Based DC-DC Converter

    NASA Astrophysics Data System (ADS)

    Wei, Chia-Ling; Wu, Lu-Yao; Yang, Hsiu-Hui; Tsai, Chien-Hung; Liu, Bin-Da; Chang, Soon-Jyh

    For battery-powered electronic products, one way to extend battery life is to use a versatile step-up/step-down DC-DC converter. A new versatile step-up/step-down switched-capacitor-based converter structure is proposed, and its efficiency is analyzed. In the step-down case, the efficiency is the same as, or even better than the efficiency of linear regulators.

  19. Sage Simulation Model for Technology Demonstration Convertor by a Step-by-Step Approach

    NASA Technical Reports Server (NTRS)

    Demko, Rikako; Penswick, L. Barry

    2006-01-01

    The development of a Stirling model using the 1-D Saga design code was completed using a step-by-step approach. This is a method of gradually increasing the complexity of the Saga model while observing the energy balance and energy losses at each step of the development. This step-by-step model development and energy-flow analysis can clarify where the losses occur, their impact, and suggest possible opportunities for design improvement.

  20. Simultaneous detection of vertical and horizontal text lines based on perceptual organization

    NASA Astrophysics Data System (ADS)

    Faure, Claudie; Vincent, Nicole

    2009-01-01

    A page of a document is a set of small components which are grouped by a human reader into higher level components, such as lines and text blocs. Document image analysis is aimed at detecting these components in document images. We propose the encoding of local information by considering the properties that determine perceptual grouping. Each connected component is labelled according to the location of its nearest neighbour connected component. These labelled components constitute the input of a rule-based incremental process. Vertical and horizontal text lines are detected without prior assumption on their direction. Touching characters belonging to different lines are detected early and discarded from the grouping process to avoid line merging. The tolerance for grouping components increases in the course of the process until the final decision. After each step of the grouping process, conflict resolution rules are activated. This work was motivated by the automatic detection of Figure&Caption pairs in the documents of the historical collection of the BIUM digital library (Bibliotheque InterUniversitaire Medicale). The images that were used in this study belong to this collection.

  1. Widespread Horizontal Gene Transfer from Circular Single-stranded DNA Viruses to Eukaryotic Genomes

    PubMed Central

    2011-01-01

    Background In addition to vertical transmission, organisms can also acquire genes from other distantly related species or from their extra-chromosomal elements (plasmids and viruses) via horizontal gene transfer (HGT). It has been suggested that phages represent substantial forces in prokaryotic evolution. In eukaryotes, retroviruses, which can integrate into host genome as an obligate step in their replication strategy, comprise approximately 8% of the human genome. Unlike retroviruses, few members of other virus families are known to transfer genes to host genomes. Results Here we performed a systematic search for sequences related to circular single-stranded DNA (ssDNA) viruses in publicly available eukaryotic genome databases followed by comprehensive phylogenetic analysis. We conclude that the replication initiation protein (Rep)-related sequences of geminiviruses, nanoviruses and circoviruses have been frequently transferred to a broad range of eukaryotic species, including plants, fungi, animals and protists. Some of the transferred viral genes were conserved and expressed, suggesting that these genes have been coopted to assume cellular functions in the host genomes. We also identified geminivirus-like and parvovirus-like transposable elements in genomes of fungi and lower animals, respectively, and thereby provide direct evidence that eukaryotic transposons could derive from ssDNA viruses. Conclusions Our discovery extends the host range of circular ssDNA viruses and sheds light on the origin and evolution of these viruses. It also suggests that ssDNA viruses act as an unforeseen source of genetic innovation in their hosts. PMID:21943216

  2. Modeling and analysis of ORNL horizontal storage tank mobilization and mixing

    SciTech Connect

    Mahoney, L.A.; Terrones, G.; Eyler, L.L.

    1994-06-01

    The retrieval and treatment of radioactive sludges that are stored in tanks constitute a prevalent problem at several US Department of Energy sites. The tanks typically contain a settled sludge layer with non-Newtonian rheological characteristics covered by a layer of supernatant. The first step in retrieval is the mobilization and mixing of the supernatant and sludge in the storage tanks. Submerged jets have been proposed to achieve sludge mobilization in tanks, including the 189 m{sup 3} (50,000 gallon) Melton Valley Storage tanks (MVST) at Oak Ridge National Laboratory (ORNL) and the planned 378 m{sup 3} (100,000 gallon) tanks being designed as part of the MVST Capacity Increase Project (MVST-CIP). This report focuses on the modeling of mixing and mobilization in horizontal cylindrical tanks like those of the MVST design using submerged, recirculating liquid jets. The computer modeling of the mobilization and mixing processes uses the TEMPEST computational fluid dynamics program (Trend and Eyler 1992). The goals of the simulations are to determine under what conditions sludge mobilization using submerged liquid jets is feasible in tanks of this configuration, and to estimate mixing times required to approach homogeneity of the contents.

  3. A new sample applicator for isoelectric focusing in horizontal polyacrylamide gels.

    PubMed

    Altland, K; Becher, P

    1988-09-01

    A new sample applicator for horizontal flat gels is described. The applicator is practically safe against contamination from adjacent samples and can be used for all types of electrophoretic separations including a concentration step for either the sample (i.e. disc electrophoresis) or the separated zones (i.e. isoelectric focusing). The applicator is a piece of flat glass with 26 or 51 parallel 2 mm wide grooves, drilled at distances of 9 or 4.5 mm. Samples, maximally 25 or 50, are applied to the areas between the grooves. By inverting the applicator, the samples are brought into close vicinity to the gel surface and the pendant droplets expand by capillary attraction into the slits between the glass and gel with resultant even distribution across the lanes of 2.5 or 7 mm width. The applicator can be used for separations with and without protection of the electrophoretic setup by paraffin oil and allows for fast multiple handling of samples by means of appropriate syringes and microtiter plates.

  4. Effects of intermittent loading on nitrogen removal in horizontal subsurface flow wetlands.

    PubMed

    Forbes, Margaret G; Yelderman, Joe C; Potterton, Tina; Doyle, Robert D

    2010-01-01

    Removal of CBOD(5) and nitrogen from septic tank effluent was evaluated in four horizontal subsurface flow (HSSF) wetlands. An intermittently loaded cell was compared to a continuously loaded control cell, with both treatments receiving the same weekly volume. The intermittent cell was rapidly drained and "rested" for 24-hr, then refilled in steps, twice weekly. Two media with different particle sizes but similar porosities were also compared. The two media, light weight expanded shale and gravel, were both continuously loaded. As hypothesized, the wetland cell that was intermittently loaded had higher dissolved oxygen, greater ammonia removal, and greater nitrate production than the continuously loaded cells. Areal NH(3)-N removal for the intermittently loaded cell was 0.90 g m(-2) d(-1) compared to 0.47 g m(-2) d(-1) for the control. Ammonia removal was also higher in continuously loaded gravel cells than in cells with expanded shale. Ammonia-N removal was an order of magnitude lower in a similar SSF wetland that had been in operation for 3 years. However, CBOD(5), total suspended solids, and total nitrogen did not vary substantially among the treatments.

  5. Effects of intermittent loading on nitrogen removal in horizontal subsurface flow wetlands.

    PubMed

    Forbes, Margaret G; Yelderman, Joe C; Potterton, Tina; Doyle, Robert D

    2010-01-01

    Removal of CBOD(5) and nitrogen from septic tank effluent was evaluated in four horizontal subsurface flow (HSSF) wetlands. An intermittently loaded cell was compared to a continuously loaded control cell, with both treatments receiving the same weekly volume. The intermittent cell was rapidly drained and "rested" for 24-hr, then refilled in steps, twice weekly. Two media with different particle sizes but similar porosities were also compared. The two media, light weight expanded shale and gravel, were both continuously loaded. As hypothesized, the wetland cell that was intermittently loaded had higher dissolved oxygen, greater ammonia removal, and greater nitrate production than the continuously loaded cells. Areal NH(3)-N removal for the intermittently loaded cell was 0.90 g m(-2) d(-1) compared to 0.47 g m(-2) d(-1) for the control. Ammonia removal was also higher in continuously loaded gravel cells than in cells with expanded shale. Ammonia-N removal was an order of magnitude lower in a similar SSF wetland that had been in operation for 3 years. However, CBOD(5), total suspended solids, and total nitrogen did not vary substantially among the treatments. PMID:20962402

  6. Spatial-temporal stability analysis of faceted growth with application to horizontal ribbon growth

    NASA Astrophysics Data System (ADS)

    Helenbrook, Brian T.; Barlow, Nathaniel S.

    2016-11-01

    Spatial-temporal stability analysis has been applied to a solidification model that includes both isotropic and non-isotropic kinetics. In agreement with previous temporal stability analyses, it was shown that the kinetics associated with the propagation of steps across a facet can stabilize solidification processes that would normally be thermally unstable. In cases where the solidification is unstable, it was also shown that pulling the solid with a tangential velocity can cause a transition from "absolute" instability where perturbations cause growth at all locations to "convective" instability where a perturbation grows as it propagates, but at any fixed location disturbances decay away after the perturbation passes. These results were applied to understand instabilities in the floating silicon method (FSM), which is a particular type of horizontal ribbon growth. It was shown that increasing pull-speeds in FSM leads to increasingly unstable thermal growth conditions, but the combination of the kinetics of faceted growth and the tangential pull velocity can stabilize the process. As the pull speed increases, however, the process becomes increasingly sensitive to perturbation.

  7. Multi-step contrast sensitivity gauge

    SciTech Connect

    Quintana, Enrico C; Thompson, Kyle R; Moore, David G; Heister, Jack D; Poland, Richard W; Ellegood, John P; Hodges, George K; Prindville, James E

    2014-10-14

    An X-ray contrast sensitivity gauge is described herein. The contrast sensitivity gauge comprises a plurality of steps of varying thicknesses. Each step in the gauge includes a plurality of recesses of differing depths, wherein the depths are a function of the thickness of their respective step. An X-ray image of the gauge is analyzed to determine a contrast-to-noise ratio of a detector employed to generate the image.

  8. Surface-Step-Induced Oscillatory Oxide Growth

    NASA Astrophysics Data System (ADS)

    Li, Liang; Luo, Langli; Ciston, Jim; Saidi, Wissam A.; Stach, Eric A.; Yang, Judith C.; Zhou, Guangwen

    2014-09-01

    We report in situ atomic-resolution transmission electron microscopy observations of the oxidation of stepped Cu surfaces. We find that the presence of surface steps both inhibits oxide film growth and leads to the oxide decomposition, thereby resulting in oscillatory oxide film growth. Using atomistic simulations, we show that the oscillatory oxide film growth is induced by oxygen adsorption on the lower terrace along the step edge, which destabilizes the oxide film formed on the upper terrace.

  9. Progressive micrographia shown in horizontal, but not vertical, writing in Parkinson's disease.

    PubMed

    Ma, Hui-Ing; Hwang, Wen-Juh; Chang, Shao-Hsia; Wang, Tsui-Ying

    2013-01-01

    All published studies on micrographia, a diminution of letter size, examine handwriting in the horizontal direction. Writing horizontally typically requires increased wrist extension as handwriting progresses from left to right. Chinese characters, however, can be written not only horizontally from left to right, but also vertically from top to bottom. We examined the effect of handwriting direction on character size and stroke length. Fifteen participants with Parkinson's disease (PD) and 15 age-matched controls wrote the same Chinese characters both horizontally and vertically. Handwriting performance was recorded with a digitizing tablet, and a custom-written computer program was used to provide objective data about character size and stroke length. The PD group had a linear decrease in overall character size and horizontal strokes along the writing sequence in the horizontal direction, but not in the vertical direction. The controls had shorter horizontal strokes in the horizontal than the vertical direction, but there was no progressive shortening of stroke length along the writing sequence. The results suggest that traditionally reported progressive micrographia in horizontal writing may not be generalizable to vertical writing. The observed decrease of handwriting size in the horizontal direction suggests that micrographia in PD may be associated with wrist extension. For clinical implications, patients may mitigate their micrographia by changing handwriting direction.

  10. Formation of sporadic E under the influence of AGWs and horizontal background wind

    NASA Astrophysics Data System (ADS)

    Matiashvili, Giorgi; Dalakishvili, Giorgi; Didebulidze, Goderdzi G.

    2016-04-01

    It is shown that the declined propagation of atmospheric gravity waves (AGWs) (with horizontal kx,ky≠0and vertical wavenumbers kz≠0) can influence the horizontal and vertical convergence of heavy metallic ions at the mid-latitude lower thermosphere. In the case of presence of background horizontal wind with velocity close to AGWs horizontal phase velocity and opposite to AGWs horizontal phase velocity occurs the increase of the ions vertical convergence inside regions with spatial scale of half vertical wavelength λz/2 and the formation of the multilayered sporadic E takes place. In order to investigate temporal evolution of processes related with sporadic E formation the 3-D numerical simulations are performed in the following cases (1) horizontal background wind and AGWs are absent, (2) background horizontal wind with arbitrary direction is considered and (3) AGWs and background horizontal wind ae considered along with taking into account ambipolar diffusion. In the cases of presence of AGW the ions/electron convergence in thin dense layers and formation of multi-layered sporadic E is demonstrated. It is shown that the ions/electron density of Es layers also depends on the horizontal and vertical wavelengths of AGWs' velocity perturbations. The vertical spatial location of the horizontal Es layers is determined by the vertical wavelength of AGWs. Acknowledgements: This work has been supported by Shota Rustaveli National Science Foundation grant No 31/81.

  11. A vibrators alternation stepping ultrasonic motor.

    PubMed

    Jin, Jiamei; Zhao, Chunsheng

    2006-12-22

    A new concept of a vibrators alternation stepping ultrasonic motor, based on longitudinal vibrations of rectangular Langevin resonators, is presented. The new motor fed by a single-phase resource without feedback is capable of bi-directions step displacements without accumulative displacement error. The step angle is 1.44 degrees, when the 150 grooves on the rotor are used in positioning. The average rotation speed without load in one step is 16.49-14.65 rad/s, and the braking torque is 0.071-0.088 Nm in operating frequency 30 kHz and operation voltage 200 V.

  12. Steady particulate flows in a horizontal rotating cylinder

    NASA Astrophysics Data System (ADS)

    Yamane, K.; Nakagawa, M.; Altobelli, S. A.; Tanaka, T.; Tsuji, Y.

    1998-06-01

    Results of discrete element method (DEM) simulation and magnetic resonance imaging (MRI) experiments are compared for monodisperse granular materials flowing in a half-filled horizontal rotating cylinder. Because opacity is not a problem for MRI, a long cylinder with an aspect ratio ˜7 was used and the flow in a thin transverse slice near the center was studied. The particles were mustard seeds and the ratio of cylinder diameter to particle diameter was approximately 50. The parameters compared were dynamic angle of repose, velocity field in a plane perpendicular to the cylinder axis, and velocity fluctuations at rotation rates up to 30 rpm. The agreement between DEM and MRI was good when the friction coefficient and nonsphericity were adjusted in the simulation for the best fit.

  13. Studies of the horizontal vestibulo-ocular reflex in spaceflight

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Uri, John J.; Moore, Tom; Pool, Sam

    1989-01-01

    Changes in the vestibulo-ocular reflex (VOR) during space flight have been suspected of contributing to space motion sickness. The horizontal VOR was studied in nine subjects on two space shuttle missions. Active unpaced head oscillation at 0.3 Hz was used as the stimulus to examine the gain and phase of the VOR with and without visual input, as well as the visual suppression of the reflex. No statistically significant changes were noted inflight in the gains or phase shifts of the VOR during any test condition, or between space motion sickness susceptible and nonsusceptible populations. Although VOR suppression was unaffected by spaceflight, the space motion sickness-susceptible group tended to exhibit greater error in the suppression than the nonsusceptible group. It is concluded that at this stimulus frequency, VOR gain is unaffected by space-flight, and any minor individual changes do not seem to contribute to space motion sickness.

  14. Borehole survey method and apparatus for drilling substantially horizontal boreholes

    SciTech Connect

    Trowsdale, L.S.

    1982-11-30

    A borehole survey method and apparatus are claimed for use in drilling substantially horizontal boreholes through a mineral deposit wherein a dip accelerometer, a roll accelerometer assembly and a fluxgate are disposed near the drill bit, which is mounted on a bent sub, and connected to a surface computation and display unit by a cable which extends through the drill string. The dip angle of the borehole near the drill bit, the azimuth of the borehole near the drill bit and the roll angle or orientation of the bent sub are measured and selectively displayed at the surface while the drill string is in the borehole for utilization in guiding the drill bit through the mineral deposit along a predetermined path.

  15. Horizontal deflection of single particle in a paramagnetic fluid.

    PubMed

    Liu, S; Yi, Xiang; Leaper, M; Miles, N J

    2014-06-01

    This paper describes the horizontal deflection behaviour of a single particle in paramagnetic fluids under a high-gradient superconducting magnetic field. A glass box was designed to carry out experiments and test assumptions. It was found that the particles were deflected away from the magnet bore centre and particles with different density and/or susceptibility settled at a certain position on the container floor due to the combined forces of gravity and magneto-Archimedes as well as lateral buoyant (displacement) force. Matlab was chosen to simulate the movement of the particle in the magnetic fluid, the simulation results were in good accordance with experimental data. The results presented here, though, are still very much in their infancy, which could potentially form the basis of a new approach to separating materials based on a combination of density and susceptibility. PMID:24894886

  16. SPRITE MRI of bubbly flow in a horizontal pipe.

    PubMed

    Sankey, Mark; Yang, Zhi; Gladden, Lynn; Johns, Michael L; Lister, Derek; Newling, Benedict

    2009-08-01

    Bubble flow is characterised by numerous phase interfaces and turbulence, leading to fast magnetic resonance signal decay and artefacts in spin-warp imaging. In this paper, the SPRITE MRI pulse sequence, with its potential for very short encoding times, is demonstrated as an ideal technique for studying such dynamic systems. It has been used to acquire liquid velocity and relative intensity maps of two-phase gas-liquid dispersed bubble flow in a horizontal pipe at a liquid Reynolds number of 14,500. The fluids were air and water and a turbulence grid was used to generate a dispersed bubble flow pattern. The SPRITE technique shows promise for future research in gas-liquid flow. PMID:19481190

  17. An appraisal of straight bladed vertical and horizontal windmills

    NASA Astrophysics Data System (ADS)

    McAnulty, K. F.

    Vertical (VA) and horizontal axis (HA) windmills were compared in uniform wind and free air tests. Free air performance for both types is similar. The absence of yaw control mechanism is a significant factor in favor of the VA type. Pitch control over the entire blade allows both types to operate in high winds. Cyclic stall in high wind speeds makes extensive (whole blade) pitch control essential for VA machines, and incurs an unquantified penalty in terms of rotor complexity and tower head weight. There is no favored output shaft arrangement. The simple blade shape of VA machines should result in cost savings. The dynamic characteristics of VA machines are uncertain, in contrast to a well developed and validated analysis for the HA type. If light weight rotors can be built for VA machines (using advanced, high specific strength materials), their development to large sizes is attractive.

  18. 8. RW Meyer Sugar Mill: 18761889. Simple, singlecylinder, horizontal, reciprocating ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. RW Meyer Sugar Mill: 1876-1889. Simple, single-cylinder, horizontal, reciprocating steam engine, model No. 1, 5' x 10', 6 hp, 175 rpm. Manufactured by Ames Iron Works, Oswego, New York, 1879. View: Steam engine powered the mill's centrifugals. It received steam from the locomotive type, fire-tube portable boiler in the background. The engine's water pump which pumped water from the feed-water clarifying cistern, in between the boiler and engine, through a pre-heat system and on to the boiler, is seen in front of the fluted cylinder. The fly-ball governor, missing its balls, the steam port, and manual throttle valve are above and behind the cylinder. The flywheel, drive shaft, and pulley are on the left side of the engine bed. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

  19. 21. RW Meyer Sugar Mill: 18761889. Simple, singlecylinder, horizontal, reciprocating ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. RW Meyer Sugar Mill: 1876-1889. Simple, single-cylinder, horizontal, reciprocating steam engine, model no. 1, 5' x 10', 6 hp, 175 rpm. Manufactured by Ames Iron Works, Oswego, New York, 1879. View: Steam engine powered the mill's centrifugals. Steam-feed pipe at top left of engine. Steam exhaust pipe leaves base of engine on right end and projects upwards. The boiler feed and supply pipe running water through the engine's pre-heat system are seen running to the lower left end of the engine. Pulley in the foreground was not used. The centrifugals were powered by a belt running from the flywheel in the background. Ball-type governor and pulley are on left end of the engine. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

  20. Effect of horizontal pick and place locations on shoulder kinematics.

    PubMed

    Könemann, R; Bosch, T; Kingma, I; Van Dieën, J H; De Looze, M P

    2015-01-01

    In this study the effects of horizontal bin locations in an order picking workstation on upper arm elevation, trunk inclination and hand use were investigated. Eight subjects moved (self-paced) light or heavy products (0.2 and 3.0 kg) from a central product bin to an inner or outer order bin (at 60 or 150 cm) on the left or right side of the workstation, while movements were recorded. The outer compared to inner bin location resulted in more upper arm elevation and trunk inclination per work cycle, both in terms of number of peak values and in terms of time integrals of angles (which is a dose measure over time). Considering the peak values and time integrals per minute (instead of per work cycle), these effects are reduced, due to the higher cycle times for outer bins. Hand use (left, right or both) was not affected by order bin locations.

  1. Active Circulation Control for Horizontal Axis Wind Turbine

    NASA Astrophysics Data System (ADS)

    Dumitrache, Alexandru; Dumitrescu, Horia; Preotu, Octavian

    2011-09-01

    A based method for modeling the aerodynamics of horizontal axis wind turbine has been developed. Circulation control is implemented by tangentially blowing a small high-velocity jet over a highly curved surface, such as a rounded trailing edge. This causes the boundary layer and the jet sheet to remain attached along the curved surface due to the Coanda effect and causing the jet to turn without separation. This analysis has been validated for the experimental data of a rotor tested at NASA Ames Research Center. Comparisons have been done against measurements for surface pressure distribution, force coefficients normal and tangential to the chord line, torque and root bending moments. This approach for enhancing the circulation around the airfoil sections (and hence L/D and power production) has been examined and found to produce useful increases in power at low wind speeds.

  2. Detection of Sound Image Movement During Horizontal Head Rotation

    PubMed Central

    Ohba, Kagesho; Iwaya, Yukio; Suzuki, Yôiti

    2016-01-01

    Movement detection for a virtual sound source was measured during the listener’s horizontal head rotation. Listeners were instructed to do head rotation at a given speed. A trial consisted of two intervals. During an interval, a virtual sound source was presented 60° to the right or left of the listener, who was instructed to rotate the head to face the sound image position. Then in one of a pair of intervals, the sound position was moved slightly in the middle of the rotation. Listeners were asked to judge the interval in a trial during which the sound stimuli moved. Results suggest that detection thresholds are higher when listeners do head rotation. Moreover, this effect was found to be independent of the rotation velocity. PMID:27698993

  3. New bits, motors improve economics of slim hole horizontal wells

    SciTech Connect

    McDonald, S.; Felderhoff, F.; Fisher, K.

    1996-03-11

    The latest generation of small-diameter bits, combined with a new extended power section positive displacement motor (PDM), has improved the economics of slim hole drilling programs. As costs are driven down, redevelopment reserves are generated in the older, more established fields. New reserves result from increases in the ultimate recovery and accelerated production rates from the implementation of horizontal wells in reentry programs. This logic stimulated an entire development program for a Gulf of Mexico platform, which was performed without significant compromises in well bore geometry. The savings from this new-generation drilling system come from reducing the total number of trips required during the drilling phase. This paper reviews the design improvements of roller cone bits, PDC bits, and positive displacement motors for offshore directional drilling operations.

  4. Horizontal transmission of parthenogenesis-inducing microbes in Trichogramma wasps.

    PubMed Central

    Schilthuizen, M; Stouthamer, R

    1997-01-01

    Complete parthenogenesis (thelytoky) in species of the parasitic wasp Trichogramma is usually caused by the cytoplasmically inherited bacterium Wolbachia. This symbiont induces gamete duplication, which, in these haplodiploid organisms, results in all-female broods. Antibiotic treatment "cures' this condition, restoring normal sexual reproduction. Phylogenetic analysis of Wolbachia has shown that, in contrast with the strains in other host organisms (where the symbiont also induces different reproductive alterations), those in Trichogramma form a monophyletic group. This might be an indication of symbiont-host cocladogenesis. To test this, we performed comparative molecular phylogenetics on 20 parthenogenetic Trichogramma cultures and their Wolbachiae. We conclude that there is, in fact, little evidence for cocladogenesis. Instead, the phylogenetic distribution of the symbionts appears to result from occasional horizontal transmission, which probably takes place inside the hosts of Trichogramma parasitoids (usually lepidopteran eggs). This study therefore suggests that parthenogenesis is not only curable, it can sometimes be contagious also. PMID:9107051

  5. Pool boiling on a large horizontal flat resistance heater

    SciTech Connect

    Reguillot, F.; Witte, L.; Lienhard, J.; Poniewski, M. Kielce University of Technology, )

    1992-08-01

    Results are presented of experiments on n-pentane/Freon-113 system, carried out to investigate the film-transition boiling region where liquid-solid contacts contribute significantly to the local heat flux, using a large flat horizontal resistance heater mounted on a ceramic insulating substrate. After steady film boiling was reached, the heat flux was decreased and recorded simultaneously with the temperature measured by thermocouples attached to the lower side of the heater surface. It is shown that the observed data on the quasi-linear film boiling regime are better represented by Berenson's (1960) correlation than by Klimenko's (1981) correlation. Burnout values measured for Freon-113 compared reasonably well to available correlations for the flat plate geometry. 10 refs.

  6. Horizontal gene transfer in eukaryotes: the weak-link model.

    PubMed

    Huang, Jinling

    2013-10-01

    The significance of horizontal gene transfer (HGT) in eukaryotic evolution remains controversial. Although many eukaryotic genes are of bacterial origin, they are often interpreted as being derived from mitochondria or plastids. Because of their fixed gene pool and gene loss, however, mitochondria and plastids alone cannot adequately explain the presence of all, or even the majority, of bacterial genes in eukaryotes. Available data indicate that no insurmountable barrier to HGT exists, even in complex multicellular eukaryotes. In addition, the discovery of both recent and ancient HGT events in all major eukaryotic groups suggests that HGT has been a regular occurrence throughout the history of eukaryotic evolution. A model of HGT is proposed that suggests both unicellular and early developmental stages as likely entry points for foreign genes into multicellular eukaryotes.

  7. Maximum allowable heat flux for a submerged horizontal tube bundle

    SciTech Connect

    McEligot, D.M. |

    1996-12-31

    For application to industrial heating of large pools by immersed heat exchangers, the so called maximum allowable (or critical) heat flux is studied for unconfined tube bundles aligned horizontally in a pool without forced flow. This is the condition at which vapor blanketing is expected to be initiated. Phenomenological considerations demonstrate why the maximum allowable heat flux would be expected to be less than for single tubes. Hydrodynamic theory is applied to extend the results of Lienhard and Dhir to large submerged bundles and the consequent correlation is compared to the correlation of Palen and Small and the limited data available for saturated conditions. To date the main conclusion is that estimates of q{double_prime}{sub chf} are highly uncertain for this configuration.

  8. Helicopter Control Energy Reduction Using Moving Horizontal Tail.

    PubMed

    Oktay, Tugrul; Sal, Firat

    2015-01-01

    Helicopter moving horizontal tail (i.e., MHT) strategy is applied in order to save helicopter flight control system (i.e., FCS) energy. For this intention complex, physics-based, control-oriented nonlinear helicopter models are used. Equations of MHT are integrated into these models and they are together linearized around straight level flight condition. A specific variance constrained control strategy, namely, output variance constrained Control (i.e., OVC) is utilized for helicopter FCS. Control energy savings due to this MHT idea with respect to a conventional helicopter are calculated. Parameters of helicopter FCS and dimensions of MHT are simultaneously optimized using a stochastic optimization method, namely, simultaneous perturbation stochastic approximation (i.e., SPSA). In order to observe improvement in behaviors of classical controls closed loop analyses are done.

  9. Helicopter Control Energy Reduction Using Moving Horizontal Tail

    PubMed Central

    Oktay, Tugrul; Sal, Firat

    2015-01-01

    Helicopter moving horizontal tail (i.e., MHT) strategy is applied in order to save helicopter flight control system (i.e., FCS) energy. For this intention complex, physics-based, control-oriented nonlinear helicopter models are used. Equations of MHT are integrated into these models and they are together linearized around straight level flight condition. A specific variance constrained control strategy, namely, output variance constrained Control (i.e., OVC) is utilized for helicopter FCS. Control energy savings due to this MHT idea with respect to a conventional helicopter are calculated. Parameters of helicopter FCS and dimensions of MHT are simultaneously optimized using a stochastic optimization method, namely, simultaneous perturbation stochastic approximation (i.e., SPSA). In order to observe improvement in behaviors of classical controls closed loop analyses are done. PMID:26180841

  10. The Feasibility of Railgun Horizontal-Launch Assist

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C.; Cox, Robert B.

    2011-01-01

    Railguns typically operate for a few milliseconds, supplying thousands of G's of acceleration to a small projectile, resulting in exceptional speeds. This paper argues through analysis and experiment, that this "standard" technology can be modified to provide 2-3 G's acceleration to a relatively heavy launch vehicle for a time period exceeding several seconds, yielding a launch assist velocity in excess of Mach 1. The key insight here is that an efficient rail gun operates at a speed approximately given by the system resistance divided by the inductance gradient, which can be tailored because recent MOSFET and ultra-capacitor advances allow very low total power supply resistances with high capacitance and augmented railgun architectures provide a scalable inductance gradient. Consequently, it should now be possible to construct a horizontal launch assist system utilizing railgun based architecture.

  11. Gravity wave turbulence revealed by horizontal vibrations of the container.

    PubMed

    Issenmann, B; Falcon, E

    2013-01-01

    We experimentally study the role of forcing on gravity-capillary wave turbulence. Previous laboratory experiments using spatially localized forcing (vibrating blades) have shown that the frequency power-law exponent of the gravity wave spectrum depends on the forcing parameters. By horizontally vibrating the whole container, we observe a spectrum exponent that does not depend on the forcing parameters for both gravity and capillary regimes. This spatially extended forcing leads to a gravity spectrum exponent in better agreement with the theory than by using a spatially localized forcing. The role of the vessel shape has been also studied. Finally, the wave spectrum is found to scale linearly with the injected power for both regimes whatever the forcing type used.

  12. Human vertical eye movement responses to earth horizontal pitch

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Petropoulos, A. E.

    1993-01-01

    The vertical eye movements in humans produced in response to head-over-heels constant velocity pitch rotation about a horizontal axis resemble those from other species. At 60 degrees/s these are persistent and tend to have non-reversing slow components that are compensatory to the direction of rotation. In most, but not all subjects, the slow component velocity was well characterized by a rapid build-up followed by an exponential decay to a non-zero baseline. Super-imposed was a cyclic or modulation component whose frequency corresponded to the time for one revolution and whose maximum amplitude occurred during a specific head orientation. All response components (exponential decay, baseline and modulation) were larger during pitch backward compared to pitch forward runs. Decay time constants were shorter during the backward runs, thus, unlike left to right yaw axis rotation, pitch responses display significant asymmetries between paired forward and backward runs.

  13. New airfoils for small horizontal axis wind turbines

    SciTech Connect

    Giguere, P.; Selig, M.S.

    1997-12-31

    In a continuing effort to enhance the performance of small energy systems, one root airfoil and three primary airfoils were specifically designed for small horizontal axis wind turbines. These airfoils are intended primarily for 1-10 kW variable-speed wind turbines for both conventional (tapered/twisted) or pultruded blades. The four airfoils were wind-tunnel tested at Reynolds numbers between 100,000 and 500,000. Tests with simulated leading-edge roughness were also conducted. The results indicate that small variable-speed wind turbines should benefit from the use of the new airfoils which provide enhanced lift-to-drag ratio performance as compared with previously existing airfoils.

  14. Horizontally rotated cell culture system with a coaxial tubular oxygenator

    NASA Technical Reports Server (NTRS)

    Wolf, David A. (Inventor); Schwarz, Ray P. (Inventor); Trinh, Tinh T. (Inventor)

    1991-01-01

    The present invention relates to a horizontally rotating bioreactor useful for carrying out cell and tissue culture. For processing of mammalian cells, the system is sterilized and fresh fluid medium, microcarrier beads, and cells are admitted to completely fill the cell culture vessel. An oxygen containing gas is admitted to the interior of the permeable membrane which prevents air bubbles from being introduced into the medium. The cylinder is rotated at a low speed within an incubator so that the circular motion of the fluid medium uniformly suspends the microbeads throughout the cylinder during the cell growth period. The unique design of this cell and tissue culture device was initially driven by two requirements imposed by its intended use for feasibility studies for three dimensional culture of living cells and tissues in space by JSC. They were compatible with microgravity and simulation of microgravity in one G. The vessels are designed to approximate the extremely quiescent low shear environment obtainable in space.

  15. Heat and momentum transport scalings in horizontal convection

    NASA Astrophysics Data System (ADS)

    Shishkina, Olga; Grossmann, Siegfried; Lohse, Detlef

    2016-02-01

    In a horizontal convection (HC) system heat is supplied and removed exclusively through a single, top, or bottom, surface of a fluid layer. It is commonly agreed that in the studied Rayleigh number (Ra) range, the convective heat transport, measured by the Nusselt number, follows the Rossby (1965) scaling, which is based on the assumptions that the HC flows are laminar and determined by their boundary layers. However, the universality of this scaling is questionable, as these flows are observed to become more turbulent with increasing Ra. Here we propose a theoretical model for heat and momentum transport scalings with Ra, which is based on the Grossmann and Lohse (2000) ideas, applied to HC flows. The obtained multiple scaling regimes include in particular the Rossby scaling and the ultimate scaling by Siggers et al. (2004). Our results have bearing on the understanding of the convective processes in many geophysical systems and engineering applications.

  16. Horizontally acquired genomic islands in the tubercle bacilli.

    PubMed

    Jang, Jichan; Becq, Jennifer; Gicquel, Brigitte; Deschavanne, Patrick; Neyrolles, Olivier

    2008-07-01

    Most mycobacteria are environmental species, causing disease only occasionally when they encounter a susceptible human or animal host. A few species, such as Mycobacterium tuberculosis and Mycobacterium avium, have acquired the ability to parasitize host macrophages during the course of evolution and have become major pathogens. Recent genetic studies in these two species have suggested that early episodes of horizontal transfer of genomic islands from surrounding environmental species might have contributed to the evolution towards this virulence phenotype, possibly by helping bacilli to persist in protozoa and, subsequently, in mammalian phagocytes. A better understanding of the function of the proteins encoded by these genomic islands in mycobacterial metabolism might help to define novel targets for the development of future antimicrobials.

  17. Condensation heat transfer of steam on a single horizontal tube

    NASA Astrophysics Data System (ADS)

    Graber, K. A.

    1983-06-01

    An experimental apparatus was designed, constructed and instrumented in an effort to systematically and carefully study the condensation heat-transfer coefficient on a single, horizontal tube. A smooth, thick-walled copper tube of length 133.5 mm, with an outside diameter of 15.9 mm and an inside diameter of 12.7 mm was instrumented with six wall thermocouples. The temperature rise across the test section was measured accurately using quartz crystal thermometers. The inside heat-transfer coefficient was determined using the Sieder-Tate correlation with leading coefficient of 0.029. Initial steam side data were taken at atmospheric pressure to test the data acquisition/reduction computer programs.

  18. Rapid DNA sequencing by horizontal ultrathin gel electrophoresis.

    PubMed Central

    Brumley, R L; Smith, L M

    1991-01-01

    A horizontal polyacrylamide gel electrophoresis apparatus has been developed that decreases the time required to separate the DNA fragments produced in enzymatic sequencing reactions. The configuration of this apparatus and the use of circulating coolant directly under the glass plates result in heat exchange that is approximately nine times more efficient than passive thermal transfer methods commonly used. Bubble-free gels as thin as 25 microns can be routinely cast on this device. The application to these ultrathin gels of electric fields up to 250 volts/cm permits the rapid separation of multiple DNA sequencing reactions in parallel. When used in conjunction with 32P-based autoradiography, the DNA bands appear substantially sharper than those obtained in conventional electrophoresis. This increased sharpness permits shorter autoradiographic exposure times and longer sequence reads. Images PMID:1870968

  19. Zonal isolation and evaluation for cemented horizontal liners

    SciTech Connect

    Gai, H; Summers, T.D.; Cocking, D.A.; Greaves, C.

    1996-12-01

    This paper discusses the novel application of technology in the cementing and bond evaluation from the world-record breaking extended-reach drilling (ERD) wells in Wytch Farm, where horizontal liners of the order of 800 to 1,300 m at TVD of approximately 1,600 m have been successfully cemented and perforated. Detailed analysis of the conditions by a multidisciplinary team provided some practical procedures that enabled the authors to achieve their objectives of zonal isolation and cement bond evaluation successfully. Important aspects of zonal isolation, such as the use of spiral-blade centralizers, rotating the liner, and trials of the external casing packer (ECP), are discussed in detail. Cement bond evaluation is also detailed, involving coiled tubing (CT) deployment and various bond-logging tools, including ultrasonic tools. The cement bond log (CBL) was found to be surprisingly reliable if used correctly.

  20. Summary of tower designs for large horizontal axis wind turbines

    NASA Technical Reports Server (NTRS)

    Frederick, G. R.; Savino, J. M.

    1986-01-01

    Towers for large horizontal axis wind turbines, machines with a rotor axis height above 30 meters and rated at more than 500 kW, have varied in configuration, materials of construction, type of construction, height, and stiffness. For example, the U.S. large HAWTs have utilized steel truss type towers and free-standing steel cylindrical towers. In Europe, the trend has been to use only free-standing and guyed cylindrical towers, but both steel and reinforced concrete have been used as materials of construction. These variations in materials of construction and type of construction reflect different engineering approaches to the design of cost effective towers for large HAWTs. Tower designs are the NASA/DOE Mod-5B presently being fabricated. Design goals and requirements that influence tower configuration, height and materials are discussed. In particular, experiences with United States large wind turbine towers are elucidated. Finally, current trends in tower designs for large HAWTs are highlighted.