WorldWideScience

Sample records for cultivator-flat cutting sweep

  1. Defining the effect of sweep tillage tool cutting edge geometry on tillage forces using 3D discrete element modelling

    Directory of Open Access Journals (Sweden)

    Mustafa Ucgul

    2015-09-01

    Full Text Available The energy required for tillage processes accounts for a significant proportion of total energy used in crop production. In many tillage processes decreasing the draft and upward vertical forces is often desired for reduced fuel use and improved penetration, respectively. Recent studies have proved that the discrete element modelling (DEM can effectively be used to model the soil–tool interaction. In his study, Fielke (1994 [1] examined the effect of the various tool cutting edge geometries, namely; cutting edge height, length of underside rub, angle of underside clearance, on draft and vertical forces. In this paper the experimental parameters of Fielke (1994 [1] were simulated using 3D discrete element modelling techniques. In the simulations a hysteretic spring contact model integrated with a linear cohesion model that considers the plastic deformation behaviour of the soil hence provides better vertical force prediction was employed. DEM parameters were determined by comparing the experimental and simulation results of angle of repose and penetration tests. The results of the study showed that the simulation results of the soil-various tool cutting edge geometries agreed well with the experimental results of Fielke (1994 [1]. The modelling was then used to simulate a further range of cutting edge geometries to better define the effect of sweep tool cutting edge geometry parameters on tillage forces. The extra simulations were able to show that by using a sharper cutting edge with zero vertical cutting edge height the draft and upward vertical force were further reduced indicating there is benefit from having a really sharp cutting edge. The extra simulations also confirmed that the interpolated trends for angle of underside clearance as suggested by Fielke (1994 [1] where correct with a linear reduction in draft and upward vertical force for angle of underside clearance between the ranges of −25 and −5°, and between −5 and 0°. The

  2. Cutting

    Science.gov (United States)

    ... a traumatic experience, such as living through abuse , violence, or a disaster. Self-injury may feel like ... embarrassed." Sometimes self-injury affects a person's body image. Jen says, "I actually liked how the cuts ...

  3. Sweeping the State Space

    DEFF Research Database (Denmark)

    Mailund, Thomas

    The thesis describes the sweep-line method, a newly developed reduction method for alleviating the state explosion problem inherent in explicit-state state space exploration. The basic idea underlying the sweep-line method is, when calculating the state space, to recognise and delete states...... that are not reachable from the currently unprocessed states. Intuitively we drag a sweep-line through the state space with the invariant that all states behind the sweep-line have been processed and are unreachable from the states in front of the sweep-line. When calculating the state space of a system we iteratively...

  4. Sweeping the State Space

    DEFF Research Database (Denmark)

    Mailund, Thomas

    The thesis describes the sweep-line method, a newly developed reduction method for alleviating the state explosion problem inherent in explicit-state state space exploration. The basic idea underlying the sweep-line method is, when calculating the state space, to recognise and delete states...... that are not reachable from the currently unprocessed states. Intuitively we drag a sweep-line through the state space with the invariant that all states behind the sweep-line have been processed and are unreachable from the states in front of the sweep-line. When calculating the state space of a system we iteratively...

  5. Cache Oblivious Distribution Sweeping

    DEFF Research Database (Denmark)

    Brodal, G.S.; Fagerberg, R.

    2002-01-01

    We adapt the distribution sweeping method to the cache oblivious model. Distribution sweeping is the name used for a general approach for divide-and-conquer algorithms where the combination of solved subproblems can be viewed as a merging process of streams. We demonstrate by a series of algorithms...

  6. Bubble-sweeping mechanisms

    Institute of Scientific and Technical Information of China (English)

    WANG; Hao; (王; 昊); PENG; Xiaofeng; (彭晓峰); WANG; Buxuan; (王补宣); LEE; Duzhong; (李笃中)

    2003-01-01

    A series of subcooled boiling experiments was conducted on very small platinum wires having diameters of 0.1 and 0.025 mm. Vapor bubbles were visually observed to sweep back and forth along the wires in the experiments. The dynamic characteristics of bubble-sweeping phenomenon are described, and the induced bubble interaction and nonlinear growth are investigated to understand the boiling heat transfer mechanisms. An unsymmetrical temperature model is proposed to explain the physical mechanism.

  7. Detection and reconstruction of freeform sweeps

    KAUST Repository

    Barton, Michael

    2014-05-01

    We study the difficult problem of deciding if parts of a freeform surface can be generated, or approximately generated, by the motion of a planar profile through space. While this task is basic for understanding the geometry of shapes as well as highly relevant for manufacturing and building construction, previous approaches were confined to special cases like kinematic surfaces or "moulding" surfaces. The general case remained unsolved so far. We approach this problem by a combination of local and global methods: curve analysis with regard to "movability", curve comparison by common substring search in curvature plots, an exhaustive search through all planar cuts enhanced by quick rejection procedures, the ordering of candidate profiles and finally, global optimization. The main applications of our method are digital reconstruction of CAD models exhibiting sweep patches, and aiding in manufacturing freeform surfaces by pointing out those parts which can be approximated by sweeps. © 2014 The Author(s) Computer Graphics Forum © 2014 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

  8. Cooperative Research Twin Trawl Sweep Comparison Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Twin-Trawl Sweep Efficiency Study" was intended to compare the sweep efficiency and selectivity of the NEFSC standardized bottom trawl to that of a standardized...

  9. PARALLEL IMPLEMENTATIONS OF THE FAST SWEEPING METHOD

    Institute of Scientific and Technical Information of China (English)

    Hongkai Zhao

    2007-01-01

    The fast sweeping method is an efficient iterative method for hyperbolic problems.It combines Gauss-Seidel iterations with alternating sweeping orderings.In this paper several parallel implementations of the fast sweeping method are presented. These parallel algorithms are simple and efficient due to the causality of the underlying partial different equations. Numerical examples are used to verify our algorithms.

  10. Research related to variable sweep aircraft development

    Science.gov (United States)

    Polhamus, E. C.; Toll, T. A.

    1981-01-01

    Development in high speed, variable sweep aircraft research is reviewed. The 1946 Langley wind tunnel studies related to variable oblique and variable sweep wings and results from the X-5 and the XF1OF variable sweep aircraft are discussed. A joint program with the British, evaluation of the British "Swallow", development of the outboard pivot wing/aft tail configuration concept by Langley, and the applied research program that followed and which provided the technology for the current, variable sweep military aircraft is outlined. The relative state of variable sweep as a design option is also covered.

  11. Image plane sweep volume illumination.

    Science.gov (United States)

    Sundén, Erik; Ynnerman, Anders; Ropinski, Timo

    2011-12-01

    In recent years, many volumetric illumination models have been proposed, which have the potential to simulate advanced lighting effects and thus support improved image comprehension. Although volume ray-casting is widely accepted as the volume rendering technique which achieves the highest image quality, so far no volumetric illumination algorithm has been designed to be directly incorporated into the ray-casting process. In this paper we propose image plane sweep volume illumination (IPSVI), which allows the integration of advanced illumination effects into a GPU-based volume ray-caster by exploiting the plane sweep paradigm. Thus, we are able to reduce the problem complexity and achieve interactive frame rates, while supporting scattering as well as shadowing. Since all illumination computations are performed directly within a single rendering pass, IPSVI does not require any preprocessing nor does it need to store intermediate results within an illumination volume. It therefore has a significantly lower memory footprint than other techniques. This makes IPSVI directly applicable to large data sets. Furthermore, the integration into a GPU-based ray-caster allows for high image quality as well as improved rendering performance by exploiting early ray termination. This paper discusses the theory behind IPSVI, describes its implementation, demonstrates its visual results and provides performance measurements.

  12. Surfactant enhanced volumetric sweep efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J.H.; Scamehorn, J.F.

    1989-10-01

    Surfactant-enhanced waterflooding is a novel EOR method aimed to improve the volumetric sweep efficiencies in reservoirs. The technique depends upon the ability to induce phase changes in surfactant solutions by mixing with surfactants of opposite charge or with salts of appropriate type. One surfactant or salt solution is injected into the reservoir. It is followed later by injection of another surfactant or salt solution. The sequence of injections is arranged so that the two solutions do not mix until they are into the permeable regions well away from the well bore. When they mix at this point, by design they form a precipitate or gel-like coacervate phase, plugging this permeable region, forcing flow through less permeable regions of the reservoir, improving sweep efficiency. The selectivity of the plugging process is demonstrated by achieving permeability reductions in the high permeable regions of Berea sandstone cores. Strategies were set to obtain a better control over the plug placement and the stability of plugs. A numerical simulator has been developed to investigate the potential increases in oil production of model systems. Furthermore, the hardness tolerance of anionic surfactant solutions is shown to be enhanced by addition of monovalent electrolyte or nonionic surfactants. 34 refs., 32 figs., 8 tabs.

  13. TIME CALIBRATED OSCILLOSCOPE SWEEP CIRCUIT

    Science.gov (United States)

    Smith, V.L.; Carstensen, H.K.

    1959-11-24

    An improved time calibrated sweep circuit is presented, which extends the range of usefulness of conventional oscilloscopes as utilized for time calibrated display applications in accordance with U. S. Patent No. 2,832,002. Principal novelty resides in the provision of a pair of separate signal paths, each of which is phase and amplitude adjustable, to connect a high-frequency calibration oscillator to the output of a sawtooth generator also connected to the respective horizontal deflection plates of an oscilloscope cathode ray tube. The amplitude and phase of the calibration oscillator signals in the two signal paths are adjusted to balance out feedthrough currents capacitively coupled at high frequencies of the calibration oscillator from each horizontal deflection plate to the vertical plates of the cathode ray tube.

  14. Traveling waves of selective sweeps

    CERN Document Server

    Durrett, Rick

    2009-01-01

    The goal of cancer genome sequencing projects is to determine the genetic alterations that cause common cancers. Many malignancies arise during the clonal expansion of a benign tumor which motivates the study of recurrent selective sweeps in an exponentially growing population. To better understand this process, Beerenwinkel et al.(2007) consider a Wright-Fisher model in which cells from an exponentially growing population accumulate advantageous mutations. Simulations show a traveling wave in which the time of the first k-fold mutant, $\\tau_k$, is approximately linear in $k$ and heuristics are used to obtain formulas for $E\\tau_k$. Here, we consider the analogous problem for the Moran model and prove that as the mutation rate $\\mu\\to 0$, $\\tau_k \\sim c_k \\log(1/\\mu)$, where the $c_k$ can be computed explicitly.

  15. Network models of frequency modulated sweep detection.

    Directory of Open Access Journals (Sweden)

    Steven Skorheim

    Full Text Available Frequency modulated (FM sweeps are common in species-specific vocalizations, including human speech. Auditory neurons selective for the direction and rate of frequency change in FM sweeps are present across species, but the synaptic mechanisms underlying such selectivity are only beginning to be understood. Even less is known about mechanisms of experience-dependent changes in FM sweep selectivity. We present three network models of synaptic mechanisms of FM sweep direction and rate selectivity that explains experimental data: (1 The 'facilitation' model contains frequency selective cells operating as coincidence detectors, summing up multiple excitatory inputs with different time delays. (2 The 'duration tuned' model depends on interactions between delayed excitation and early inhibition. The strength of delayed excitation determines the preferred duration. Inhibitory rebound can reinforce the delayed excitation. (3 The 'inhibitory sideband' model uses frequency selective inputs to a network of excitatory and inhibitory cells. The strength and asymmetry of these connections results in neurons responsive to sweeps in a single direction of sufficient sweep rate. Variations of these properties, can explain the diversity of rate-dependent direction selectivity seen across species. We show that the inhibitory sideband model can be trained using spike timing dependent plasticity (STDP to develop direction selectivity from a non-selective network. These models provide a means to compare the proposed synaptic and spectrotemporal mechanisms of FM sweep processing and can be utilized to explore cellular mechanisms underlying experience- or training-dependent changes in spectrotemporal processing across animal models. Given the analogy between FM sweeps and visual motion, these models can serve a broader function in studying stimulus movement across sensory epithelia.

  16. Reverse spontaneous laser line sweeping in ytterbium fiber laser

    Science.gov (United States)

    Navratil, P.; Peterka, P.; Honzatko, P.; Kubecek, V.

    2017-03-01

    Self-induced laser line sweeping of various regimes of sweep direction is reported for an experimental ytterbium fiber laser. The regimes involve sweeping from shorter to longer wavelengths (1076~\\text{nm}\\to 1083 nm)—so-called normal self-sweeping; from longer to shorter wavelengths (1079~\\text{nm}\\to 1073 nm)—so-called reverse self-sweeping; and a mixed regime in which a precarious balance of the normal and reverse sweeping exists and the sweep direction can change between consecutive sweeps. The regimes of sweeping were selected by changing the pump wavelength only. A detailed explanation of this sweep direction dynamics is presented based on a semi-empirical model. This model also provides a way to predict the sweep direction of fiber lasers based on other rare-earth-doped laser media.

  17. DEVELOPMENT AND RESEARCH OF A CORN HARVESTER WITH SWEEP FRAME DESIGN

    Directory of Open Access Journals (Sweden)

    Serga G. V.

    2016-09-01

    Full Text Available The article demonstrates a possibility of creation of a corn harvester with a sweep frame mounted from individual modules. Such corn harvesters include modules for cutting stalks, snapping modules, conveyor modules for turning, stacking and feeding the stalks in the shredding unit, conveyor modules for supplying corncobs to the cleaning device placed on the sweep frame, leading and managing bridges, power unit, as well as conveyor belt for cobs and auger for discharging the crushed plant matter. The technique for calculating the grinding module drive was shown. The arrangement of the modules on the corn harvester sweep frame was demonstrated. Corn harvesting with the suggested module corn harvester allows not only reducing combine metal consumption and reducing corn ears injuring, but improving maintainability as well

  18. Investigation of Spiral and Sweeping Holes

    Science.gov (United States)

    Thurman, Douglas; Poinsatte, Philip; Ameri, Ali; Culley, Dennis; Raghu, Surya; Shyam, Vikram

    2015-01-01

    Surface infrared thermography, hotwire anemometry, and thermocouple surveys were performed on two new film cooling hole geometries: spiral/rifled holes and fluidic sweeping holes. The spiral holes attempt to induce large-scale vorticity to the film cooling jet as it exits the hole to prevent the formation of the kidney shaped vortices commonly associated with film cooling jets. The fluidic sweeping hole uses a passive in-hole geometry to induce jet sweeping at frequencies that scale with blowing ratios. The spiral hole performance is compared to that of round holes with and without compound angles. The fluidic hole is of the diffusion class of holes and is therefore compared to a 777 hole and Square holes. A patent-pending spiral hole design showed the highest potential of the non-diffusion type hole configurations. Velocity contours and flow temperature were acquired at discreet cross-sections of the downstream flow field. The passive fluidic sweeping hole shows the most uniform cooling distribution but suffers from low span-averaged effectiveness levels due to enhanced mixing. The data was taken at a Reynolds number of 11,000 based on hole diameter and freestream velocity. Infrared thermography was taken for blowing rations of 1.0, 1.5, 2.0, and 2.5 at a density ration of 1.05. The flow inside the fluidic sweeping hole was studied using 3D unsteady RANS.

  19. Escape statistics for parameter sweeps through bifurcations.

    Science.gov (United States)

    Miller, Nicholas J; Shaw, Steven W

    2012-04-01

    We consider the dynamics of systems undergoing parameter sweeps through bifurcation points in the presence of noise. Of interest here are local codimension-one bifurcations that result in large excursions away from an operating point that is transitioning from stable to unstable during the sweep, since information about these "escape events" can be used for system identification, sensing, and other applications. The analysis is based on stochastic normal forms for the dynamic saddle-node and subcritical pitchfork bifurcations with a time-varying bifurcation parameter and additive noise. The results include formulation and numerical solution for the distribution of escape events in the general case and analytical approximations for delayed bifurcations for which escape occurs well beyond the corresponding quasistatic bifurcation points. These bifurcations result in amplitude jumps encountered during parameter sweeps and are particularly relevant to nano- and microelectromechanical systems, for which noise can play a significant role.

  20. Nonadiabatic exchange dynamics during adiabatic frequency sweeps.

    Science.gov (United States)

    Barbara, Thomas M

    2016-04-01

    A Bloch equation analysis that includes relaxation and exchange effects during an adiabatic frequency swept pulse is presented. For a large class of sweeps, relaxation can be incorporated using simple first order perturbation theory. For anisochronous exchange, new expressions are derived for exchange augmented rotating frame relaxation. For isochronous exchange between sites with distinct relaxation rate constants outside the extreme narrowing limit, simple criteria for adiabatic exchange are derived and demonstrate that frequency sweeps commonly in use may not be adiabatic with regard to exchange unless the exchange rates are much larger than the relaxation rates. Otherwise, accurate assessment of the sensitivity to exchange dynamics will require numerical integration of the rate equations. Examples of this situation are given for experimentally relevant parameters believed to hold for in-vivo tissue. These results are of significance in the study of exchange induced contrast in magnetic resonance imaging.

  1. Three-dimensional analysis of vane sweep effects on fan interaction noise

    Science.gov (United States)

    Zhang, Weiguang; Wang, Xiaoyu; Jing, Xiaodong; Liang, An; Sun, Xiaofeng

    2017-03-01

    The lifting surface method is an efficient solution for fully three-dimensional aerodynamic response of an annular cascade to the unsteady disturbances. Based on this response function, a prediction model for fan tonal and broadband interaction noise has been established. Three dimensional effects, including primarily the annular geometry and the radial non-uniformity of the upwash, can be fully taken into account. In this paper, a thorough analysis of vanes sweep effects is carried out by particularly considering the great dependence of the annular cascade aerodynamic response and modal acoustic field upon the radial phase profiles of incident disturbances. For fan tonal noise, different control behaviors of the forward and backward swept vanes are observed when the radial non-uniformity in the incident gust is introduced. The argument suggests that sweep should be selected so as to increase the wake intersections per vane, until it is larger than the number of cut-on radial acoustic modes. For fan broadband noise, the backward sweep succeeds in reducing the sound power level for a wide range of frequencies. Due to the statistical average effect, the efficiency relies much on the shape of the turbulence spectrum. And the sweep angle should be large enough to guarantee a preferable reduction to the fan broadband noise.

  2. Total body irradiation with a sweeping beam

    Energy Technology Data Exchange (ETDEWEB)

    Pla, M.; Chenery, S.G.; Podgorsak, E.B.

    1983-01-01

    A technique for total body irradiation, in which the patient lies in the prone or supine position in the beam of a conventional column mounted 4 MV linear accelerator, is described. A sufficiently large radiation field is obtained by rotating the beam in a vertical plane about the source (i.e., sweeping beam) at a source-to-skin distance of 190 cm on the vertical axis. The variation of the midplane dose is less than +lt. slash-5% in parallel-opposed beams, when attenuators are placed over the region containing the lungs and bolus is employed around the head and legs. The percentage depth dose for the sweeping beam is identical to that of a stationary beam for the same collimator setting and source-to-skin distance. A method for monitoring the dose to the patient by means of a thimble ionization chamber located on the vertical beam axis is outlined. The average dose rates used are between 5 and 10 cGy/min. The design and placement of lung attenuators is simple. The treatment technique with the sweeping beam requires minimal modification of a treatment unit and can be applied on any unit which has a head swivel option.

  3. Hausdorff metric BV discontinuity of sweeping processes

    Science.gov (United States)

    Klein, Olaf; Recupero, Vincenzo

    2016-06-01

    Sweeping processes are a class of evolution differential inclusions arising in elastoplasticity and were introduced by J.J. Moreau in the early seventies. The solution operator of the sweeping processes represents a relevant example of rate independent operator. As a particular case we get the so called play operator, which is a typical example of a hysteresis operator. The continuity properties of these operators were studied in several works. In this note we address the continuity with respect to the strict metric in the space of functions of bounded variation with values in the metric space of closed convex subsets of a Hilbert space. We provide counterexamples showing that for all BV-formulations of the sweeping process the corresponding solution operator is not continuous when its domain is endowed with the strict topology of BV and its codomain is endowed with the L1-topology. This is at variance with the play operator which has a BV-extension that is continuous in this case.

  4. Application of variable-sweep wings to commuter aircraft

    Science.gov (United States)

    Robins, A. W.; Beissner, F. L., Jr.; Lovell, W. A.; Price, J. E.; Turriiziani, R. V.; Washburn, F. F.

    1983-01-01

    The effects of using variable-sweep wings on the riding quality and mission-performance characteristics of commuter-type aircraft were studied. A fixed-wing baseline vehicle and a variable-sweep version of the baseline were designed and evaluated. Both vehicles were twin-turboprop, pressurized-cabin, 30-passenger commuter aircraft with identical mission requirements. Mission performance was calculated with and without various ride-quality constraints for several combinations of cruise altitude and stage lengths. The variable-sweep aircraft had a gross weight of almost four percent greater than the fixed-wing baseline in order to meet the design-mission requirements. In smooth air, the variable sweep configuration flying with low sweep had a two to three percent fuel-use penalty. However, the imposition of quality constraints in rough air can result in advantages in both fuel economy and flight time for the variable-sweep vehicle flying with high sweep.

  5. Solar Wind Earth Exchange Project (SWEEP)

    Science.gov (United States)

    2016-10-28

    AFRL-AFOSR-UK-TR-2016-0035 Solar Wind Earth Exchange Project 140200 Steven Sembay UNIVERSITY OF LEICESTER Final Report 10/28/2016 DISTRIBUTION A...To) 01 Sep 2014 to 31 Aug 2016 4. TITLE AND SUBTITLE Solar Wind Earth Exchange Project (SWEEP) 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-14-1...0200 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Steven Sembay 5d.  PROJECT NUMBER 5e.  TASK NUMBER 5f.   WORK UNIT NUMBER 7. PERFORMING

  6. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Troy Reed; Ergun Kuru

    2004-09-30

    part of this project, instrumentation was developed to monitor cuttings beds and characterize foams in the flow loop. An ultrasonic-based monitoring system was developed to measure cuttings bed thickness in the flow loop. Data acquisition software controls the system and processes the data. Two foam generating devices were designed and developed to produce foams with specified quality and texture. The devices are equipped with a bubble recognition system and an in-line viscometer to measure bubble size distribution and foam rheology, respectively. The 5-year project is completed. Future research activities will be under the umbrella of Tulsa University Drilling Research Projects. Currently the flow loop is being used for testing cuttings transport capacity of aqueous and polymer-based foams under elevated pressure and temperature conditions. Subsequently, the effect of viscous sweeps on cuttings transport under elevated pressure and temperature conditions will be investigated using the flow loop. Other projects will follow now that the ''steady state'' phase of the project has been achieved.

  7. Aggregate size distributions in sweep flocculation

    Directory of Open Access Journals (Sweden)

    Chairoj Rattanakawin

    2005-09-01

    Full Text Available The evolution of aggregate size distributions resulting from sweep flocculation has been investigated using laser light scattering technique. By measuring the (volume distributions of floc size, it is possible to distinguish clearly among floc formation, growth and breakage. Sweep flocculation of stable kaolin suspensions with ferric chloride under conditions of the rapid/slow mixing protocol produces uni-modal size distributions. The size distribution is shifted to larger floc size especially during the rapid mixing step. The variation of the distributions is also shown in the plot of cumulative percent finer against floc size. From this plot, the distributions maintain the same S-shape curves over the range of the mixing intensities/times studied. A parallel shift of the curves indicates that self-preserving size distribution occurred in this flocculation. It is suggested that some parameters from mathematical functions derived from the curves could be used to construct a model and predict the flocculating performance. These parameters will be useful for a water treatment process selection, design criteria, and process control strategies. Thus the use of these parameters should be employed in any further study.

  8. Selective sweeps in Cryptocercus woodroach antifungal proteins.

    Science.gov (United States)

    Velenovsky, Joseph F; Kalisch, Jessica; Bulmer, Mark S

    2016-10-01

    We identified the antifungal gene termicin in three species of Cryptocercus woodroaches. Cryptocercus represents the closest living cockroach lineage of termites, which suggests that the antifungal role of termicin evolved prior to the divergence of termites from other cockroaches. An analysis of Cryptocercus termicin and two β-1,3-glucanase genes (GNBP1 and GNBP2), which appear to work synergistically with termicin in termites, revealed evidence of selection in these proteins. We identified the signature of past selective sweeps within GNBP2 from Cryptocercus punctulatus and Cryptocercus wrighti. The signature of past selective sweeps was also found within termicin from Cryptocercus punctulatus and Cryptocercus darwini. Our analysis further suggests a phenotypically identical variant of GNBP2 was maintained within Cryptocercus punctulatus, Cryptocercus wrighti, and Cryptocercus darwini while synonymous sites diverged. Cryptocercus termicin and GNBP2 appear to have experienced similar selective pressure to that of their termite orthologues in Reticulitermes. This selective pressure may be a result of ubiquitous entomopathogenic fungal pathogens such as Metarhizium. This study further reveals the similarities between Cryptocercus woodroaches and termites.

  9. Improvement of Sweep Efficiency in Gasflooding

    Energy Technology Data Exchange (ETDEWEB)

    Kishore Mohanty

    2008-12-31

    Miscible and near-miscible gasflooding has proven to be one of the few cost effective enhance oil recovery techniques in the past twenty years. As the scope of gas flooding is being expanded to medium viscosity oils in shallow sands in Alaska and shallower reservoirs in the lower 48, there are questions about sweep efficiency in near-miscible regions. The goal of this research is to evaluate sweep efficiency of various gas flooding processes in a laboratory model and develop numerical tools to estimate their effectiveness in the field-scale. Quarter 5-spot experiments were conducted at reservoir pressure to evaluate the sweep efficiency of gas, WAG and foam floods. The quarter 5-spot model was used to model vapor extraction (VAPEX) experiments at the lab scale. A streamline-based compositional simulator and a commercial simulator (GEM) were used to model laboratory scale miscible floods and field-scale pattern floods. An equimolar mixture of NGL and lean gas is multicontact miscible with oil A at 1500 psi; ethane is a multicontact miscible solvent for oil B at pressures higher than 607 psi. WAG improves the microscopic displacement efficiency over continuous gas injection followed by waterflood in corefloods. WAG improves the oil recovery in the quarter 5-spot over the continuous gas injection followed by waterflood. As the WAG ratio increases from 1:2 to 2:1, the sweep efficiency in the 5-spot increases, from 39.6% to 65.9%. A decrease in the solvent amount lowers the oil recovery in WAG floods, but significantly higher amount of oil can be recovered with just 0.1 PV solvent injection over just waterflood. Use of a horizontal production well lowers the oil recovery over the vertical production well during WAG injection phase in this homogeneous 5-spot model. Estimated sweep efficiency decreases from 61.5% to 50.5%. In foam floods, as surfactant to gas slug size ratio increases from 1:10 to 1:1, oil recovery increases. In continuous gasflood VAPEX processes, as the

  10. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    Science.gov (United States)

    Spafford, Ryan D; Lortie, Christopher J

    2013-01-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  11. Cutting assembly

    Science.gov (United States)

    Racki, Daniel J.; Swenson, Clark E.; Bencloski, William A.; Wineman, Arthur L.

    1984-01-01

    A cutting apparatus includes a support table mounted for movement toward and away from a workpiece and carrying a mirror which directs a cutting laser beam onto the workpiece. A carrier is rotatably and pivotally mounted on the support table between the mirror and workpiece and supports a conduit discharging gas toward the point of impingement of the laser beam on the workpiece. Means are provided for rotating the carrier relative to the support table to place the gas discharging conduit in the proper positions for cuts made in different directions on the workpiece.

  12. Bone cutting.

    Science.gov (United States)

    Giraud, J Y; Villemin, S; Darmana, R; Cahuzac, J P; Autefage, A; Morucci, J P

    1991-02-01

    Bone cutting has always been a problem for surgeons because bone is a hard living material, and many osteotomes are still very crude tools. Technical improvement of these surgical tools has first been their motorization. Studies of the bone cutting process have indicated better features for conventional tools. Several non-conventional osteotomes, particularly ultrasonic osteotomes are described. Some studies on the possible use of lasers for bone cutting are also reported. Use of a pressurised water jet is also briefly examined. Despite their advantages, non-conventional tools still require improvement if they are to be used by surgeons.

  13. Single-sweep spectral analysis of contact heat evoked potentials

    DEFF Research Database (Denmark)

    Hansen, Tine M; Graversen, Carina; Frøkjaer, Jens B

    2015-01-01

    -sweep characteristics to identify alterations induced by morphine. METHODS: In a crossover study 15 single-sweep CHEPs were analyzed from 62 electroencephalography electrodes in 26 healthy volunteers before and after administration of morphine or placebo. Each sweep was decomposed by a continuous wavelet transform...... to obtain normalized spectral indices in the delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-32 Hz) and gamma (32-80 Hz) bands. The average distribution over all sweeps and channels was calculated for the four recordings for each volunteer, and the two recordings before treatments were assessed...

  14. Optimization and control of the sweeping range in an Yb-doped self-sweeping fiber laser

    Science.gov (United States)

    Lobach, I. A.; Tkachenko, A. Yu; Kablukov, S. I.

    2016-04-01

    Influence of the laser cavity parameters (an active fiber length and output coupling losses) and the temperature of elements (active fiber and pump laser diode) on the sweeping range in an Yb-doped self-sweeping laser is investigated. The obtained results show that the sweeping spectral region is shifted to shorter wavelengths for shorter active fibers and with increasing absorbed power. This allows one to obtain self-sweeping operation in a broad range within a ytterbium gain bandwidth from 1028 to 1080 nm. At the same time, there are optimal cavity parameters at which the sweeping span is the broadest (>20 nm). Good agreement between the experimental sweeping range and the calculated maximum gain wavelength is demonstrated.

  15. Controlling the mobility of sensors in Sweep Coverage%Sweep Coverage中的节点移动控制

    Institute of Scientific and Technical Information of China (English)

    王伟; 林锋; 周激流

    2010-01-01

    作为无线传感器网络中一种新的覆盖类型,Sweep Coverage与其他覆盖类型相比,可以使用较少的节点满足特定区域的监控需求.为了改进Sweep Coverage机制的性能,本文以Vehicle Routing Problem with Time Windows问题的模型,对Sweep coverage问题进行了分析,提出了一种基于模拟退火算法的Sweep Coverage机制(VRP-Sweep).实验结果表明,在相同的网络场景下,VRP-Sweep机制较以往的Sweep Coverage机制取得更好的性能表现.

  16. Wavelength Sweep Interferometry for Measuring the Refractive Index and Physical Thickness

    Institute of Scientific and Technical Information of China (English)

    SONG Guiju; WANG Xiangzhao; FANG Zujie

    2001-01-01

    A method combining wavelength sweep interferometry with the Fourior transform technique to perform the separate measurements of the physical thickness and the refractive index is proposed. By converting the optical path difference of the interferometer to the beat frequency of the interference signal we realize the depth scanning without mechanical moving parts. The effect of specimen dispersion is avoided by using a narrow tuning laser diode. For demonstrating this method we measure the physical thickness and the refractive index of an x-cut LiNbO3, BK9 and BK7 glass, and the results consist with the reported values.

  17. A Compositional Sweep-Line State Space Exploration Method

    DEFF Research Database (Denmark)

    Kristensen, Lars Michael; Mailund, Thomas

    2002-01-01

    State space exploration is a main approach to verification of finite-state systems. The sweep-line method exploits a certain kind of progress present in many systems to reduce peak memory usage during state space exploration. We present a new sweep-line algorithm for a compositional setting where...

  18. Periodic Sweep Coverage Scheme Based on Periodic Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Li Shu

    2014-03-01

    Full Text Available We provide a sweep coverage algorithm for routing mobile sensors that communicate with a central data sink. This algorithm improves on its predecessors by reducing the number of unnecessary scans when different points of interest (POIs have different requirements for the time interval within which they must be scanned (sweep period. Most sweep coverage algorithms seek to minimize the number of sensors required to cover a given collection of POIs. When POIs have different sweep period requirements, existing algorithms will produce solutions in which sensors visit some POIs much more frequently than is necessary. We define this as the POI Over-Coverage problem. In order to address this problem we develop a Periodic Sweep Coverage (PSC scheme based on a well-known solution to the Periodic Vehicle Routing Problem (PVRP. Our algorithm seeks a route for the mobile sensors that minimizes the number of unnecessary visits to each POI. To verify and test the proposed scheme we implemented a C++ simulation and ran scenarios with a variety of POI topologies (number and distribution of the POIs and the speed at which sensors could travel. The simulation results show that the PSC algorithm outperforms other sweep coverage algorithms such as CSweep and Vehicle Routing Problem Sweep Coverage (VRPSC on both the average number of sensors in a solution and in the computational time required to find a solution. Our results also demonstrate that the PSC scheme is more suitable for the sweep coverage scenarios in which higher speed mobile sensors are used.

  19. Selective sweeps across twenty millions years of primate evolution

    DEFF Research Database (Denmark)

    Munch, Kasper; Nam, Kiwoong; Schierup, Mikkel Heide

    2016-01-01

    The contribution from selective sweeps to variation in genetic diversity has proven notoriously difficult to assess, in part because polymorphism data only allows detection of sweeps in the most recent few hundred thousand years. Here we show how linked selection in ancestral species can be quant...

  20. Cutting Cosmos

    DEFF Research Database (Denmark)

    Mikkelsen, Henrik Hvenegaard

    The foundation for this book is an ethnographic study of masculinity in a Bugkalot village in northern Philippines. While offering new research on the Bugkalot, widely known as the Ilongot, more than 30 years after the last important works were written on this famous hill-people, Cutting Cosmos...... into egalitarian relations. Cutting Cosmos shows how these seemingly opposed characteristics of male life - the egalitarianism and the assertive ideals - are interwoven. Acts of dominance are presented as acts of transgression that are persistently ritualized, contained and isolated as spectacular events within...

  1. Influence of vane sweep on rotor-stator interaction noise

    Science.gov (United States)

    Envia, Edmane; Kerschen, Edward J.

    1990-01-01

    The influence of vane sweep in rotor-stator interaction noise is investigated. In an analytical approach, the interaction of a convected gust representing the rotor viscous wake, with a cascade of cascade of finite span swept airfoils, representing the stator, is analyzed. The analysis is based on the solution of the exact linearized equations of motion. High frequency convected gusts for which noise generation is concentrated near the leading edge of airfoils is considered. In a preliminary study, the problem of an isolated finite span swept airfoil interacting with a convected gust is analyzed. Results indicate that sweep can substantially reduce the farfield noise levels for a single airfoil. Using the single airfoil model, an approximate solution to the problem of noise radiation from a cascade of finite span swept airfoils interacting with a convected gust is derived. A parametric study of noise generated by gust cascade interaction is carried out to assess the effectiveness of vane sweep in reducing rotor-stator interaction noise. The results show that sweep is beneficial in reducing noise levels. Rotor wake twist or circumferential lean substantially influences the effectiveness of vane sweep. The orientation of vane sweep must be chosen to enhance the natural phase lag caused by wake lean, in which case rather small sweep angles substantially reduce the noise levels.

  2. Measuring long impulse responses with pseudorandom sequences and sweep signals

    DEFF Research Database (Denmark)

    Torras Rosell, Antoni; Jacobsen, Finn

    2010-01-01

    ) and inverse repeated sequences (IRS)) and with linear and logarithmic sweep signals have been examined. The results reveal that the sweep method can provide a significant reduction of the effect of distortion compared with MLS/IRS techniques but, unlike what is claimed in the literature, sweep signals cannot...... reject all distortion artifacts from the causal part of the estimated impulse response. In all cases, an improvement of 3 dB in signal-to-noise ratio can be achieved if the measurement time is doubled either by averaging over two excitations or by doubling the length of the excitation signal. The time...

  3. Sweep Width Estimation for Ground Search and Rescue

    Science.gov (United States)

    2004-12-30

    that may influence sweep width were measured during the experiments. Promising variables include SAR background, height, age, color - blindness , fatigue...123 8.3.9 Color Blindness ................................................................................................... 124... Color Blindness ................................................................................................ 200 Searcher Profile

  4. A Sweep Coverage Scheme Based on Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Li Shu

    2013-04-01

    Full Text Available As an emerging coverage problem in wireless sensor networks, sweep coverage which introducing mobile sensors to cover points of interest within certain time interval can satisfy monitoring request in some particular application scenarios with less number of nodes than the conventional static coverage approach. In this work, aiming to support dynamical POI coverage and data delivery simultaneously, a novel sweep coverage scheme, named VRPSC(Vehicle Routing Problem based Sweep Coverage, is proposed by modeling the minimum number of required sensors problem in sweep coverage as a Vehicle Routing Problem (VRP. In VRPSC, an insertion algorithm is first introduced to create the initial scanning routes for POIs, and then the Simulated Annealing is employed to optimize these routes. The simulation results show that the VRPSC scheme achieves better performance than existing schemes. 

  5. Stoichiometry and Formation Constant Determination by Linear Sweep Voltammetry.

    Science.gov (United States)

    Schultz, Franklin A.

    1979-01-01

    In this paper an experiment is described in which the equilibrium constants necessary for determining the composition and distribution of lead (II)-oxalate species may be measured by linear sweep voltammetry. (Author/BB)

  6. Theory of ring sweeping of energetic particles. [in Neptune environment

    Science.gov (United States)

    Paranicas, C. P.; Cheng, A. F.

    1991-01-01

    Because the effective 'area' of the Neptunian rings is larger than that of the inner moons, the sweeping of energetic particles by the rings is perhaps the dominant process for particle loss in the magnetosphere within 5 R(N). In this paper, a theory for calculating the absorption probability of energetic charged particles by the rings is described. The effects of a large tilt and an offset between the planet and dipole centers are included. It is found that the probability of absorption for protons is so high that the sweeping lifetime is only a few times the gradient-curvature drift period. For electrons, the sweeping lifetime is even less. The pitch angle dependence for sweeping manifests itself strongly only at large equatorial pitch angles. Lower-energy particles have higher absorption rates by the rings.

  7. A new interpretation of distortion artifacts in sweep measurements

    DEFF Research Database (Denmark)

    Torras Rosell, Antoni; Jacobsen, Finn

    2011-01-01

    The characterization of acoustical spaces by means of impulse response measurements is often biased by the nonlinear behavior of the loudspeaker used to excite the system under test. In this context the distortion immunity provided by the sweep technique has been investigated. The results show th...... that the sweep method can reject a significant amount of distortion artifacts but, in contrast to what is claimed in the literature, it cannot exclude all distortion artifacts from the causal part of the estimated impulse response....

  8. Yosida-Moreau Regularization of Sweeping Processes with Unbounded Variation

    Science.gov (United States)

    Kunze, M.; Monteiro Marques, M. D. P.

    1996-09-01

    Lett↦C(t) be a Hausdorff-continuous multifunction with closed convex values in a Hilbert spaceHsuch thatC(t) has nonempty interior for allt. We show that the Yosida-Moreau regularizations of the sweeping process with moving setC(t), i.e., the solutions of[formula]are strongly pointwisely convergent asλ→0+to the solution of the corresponding sweeping process, formally written as[formula

  9. MODELING OF AN OSCILLATORY FREELY-ROTATING CUTTING BRUSH FOR STREET SWEEPING

    Directory of Open Access Journals (Sweden)

    LIBARDO V. VANEGAS-USECHE

    2011-01-01

    Full Text Available Se desarrolla un modelo matemático de un cepillo lateral oscilatorio para barrido de calles en rotación libre. Las cerdas se modelan como vigas empotradas. La ecuación de movimiento se obtiene mediante la teoría de vibraciones forzadas de vigas, y la solución se basa en el método de modo normal. Se estudia una función sinusoidal y una novedosa función, llamada VAP. El modelo se valida mediante análisis de elementos finitos. Se identifican los efectos de los parámetros del cepillo sobre su dinámica. Para la función VAP, una condición similar a resonancia tiende a ocurrir en el plano fuerte para las deflexiones, cuando la frecuencia del cepillo es una fracción impar de una frecuencia natural de la cerda en dicho plano. El modelo sirve para estudiar las deflexiones pequeñas de una viga empotrada, sometida a vibraciones producidas por una onda sinusoidal, cuadrada, triangular o VAP.

  10. An analysis of sweep patterns for a handheld demining system

    Science.gov (United States)

    Wilson, J. N.; Gader, P. D.; Ho, K. C.; Mazhar, R.

    2006-05-01

    Handheld sensors are commonly used to assist in landmine location and removal. A number of computer systems aimed at assisting humans in discriminating between buried mines and other objects have been developed. Each such system requires some protocol that involves sweeping the sensor over a region of ground using some set of patterns to search for objects (detection) and determine the nature of those objects (discrimination). The work reported here is an effort to determine an acceptable sweep pattern for mine/nonmine discrimination that provides good performance while still being simple for the operator to use. The paper describes a series of data collections and case studies employing a combined radar and metal detection sensor. The system was evaluated first using a robotic operator and later human operators. We discuss the application of a supervised learning system discriminator to each data set, and evaluate discrimination performance. We found that using a relatively simple sweep pattern, computer algorithms can achieve better discrimination performance than an expert human operator, and that (at least up to ten sweeps) our computer algorithm performs better with more sweeps over target.

  11. Classic selective sweeps were rare in recent human evolution

    Science.gov (United States)

    Hernandez, Ryan D.; Kelley, Joanna L.; Elyashiv, Eyal; Melton, S. Cord; Auton, Adam; McVean, Gil; Sella, Guy; Przeworski, Molly

    2013-01-01

    Efforts to identify the genetic basis of human adaptations from polymorphism data have sought footprints of “classic selective sweeps”. Yet it remains unknown whether this form of natural selection was common in our evolution. We examined the evidence for classic sweeps in resequencing data from 179 human genomes. As expected under a recurrent sweep model, diversity levels decrease near exons and conserved non-coding regions. In contrast to expectation, however, the trough in diversity around human-specific amino acid substitutions is no more pronounced than around synonymous substitutions. Moreover, relative to the genome background, amino acid and putative regulatory sites are not significantly enriched for alleles that are highly differentiated between populations. These findings indicate that classic sweeps were not a dominant mode of adaptation over the past ~250,000 years. PMID:21330547

  12. Self-propelled sweeping removal of dropwise condensate

    Science.gov (United States)

    Qu, Xiaopeng; Boreyko, Jonathan B.; Liu, Fangjie; Agapov, Rebecca L.; Lavrik, Nickolay V.; Retterer, Scott T.; Feng, James J.; Collier, C. Patrick; Chen, Chuan-Hua

    2015-06-01

    Dropwise condensation can be enhanced by superhydrophobic surfaces on which the condensate drops spontaneously jump upon coalescence. However, the self-propelled jumping in prior reports is mostly perpendicular to the substrate. Here, we propose a substrate design with regularly spaced micropillars. Coalescence on the sidewalls of the micropillars leads to self-propelled jumping in a direction nearly orthogonal to the pillars and therefore parallel to the substrate. This in-plane motion in turn produces sweeping removal of multiple neighboring drops. The spontaneous sweeping mechanism may greatly enhance dropwise condensation in a self-sustained manner.

  13. A Compositional Sweep-Line State Space Exploration Method

    DEFF Research Database (Denmark)

    Kristensen, Lars Michael; Mailund, Thomas

    2002-01-01

    State space exploration is a main approach to verification of finite-state systems. The sweep-line method exploits a certain kind of progress present in many systems to reduce peak memory usage during state space exploration. We present a new sweep-line algorithm for a compositional setting where...... systems are composed of subsystems. The compositional setting makes it possible to divide subsystem progress measures into monotone and non-monotone progress measures to further reduce peak memory usage. We show that in a compositional setting, it is possible to automatically obtain a progress measure...

  14. Thermal characterization of optical fibers using wavelength-sweeping interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Perret, Luc; Pfeiffer, Pierre; Serio, Bruno; Twardowski, Patrice

    2010-06-20

    In this paper, we report a new method of thermal characterization of optical fibers using wavelength-sweeping interferometry and discuss its advantages compared to other techniques. The setup consists of two temperature-stabilized interferometers, a reference Michelson and a Mach-Zehnder, containing the fiber under test. The wavelength sweep is produced by an infrared tunable laser diode. We obtained the global phase shift coefficients of a large effective area fiber and gold-coated fiber optics with a 10{sup -7} accuracy.

  15. Using temperature sweeps to investigate rheology of bioplastics

    Science.gov (United States)

    As part of research toward production of protein-based bioplastics, small amplitude oscillatory shear analyses were performed in the temperature sweep mode to examine protein blends in the presence of wheat flour and glycerol. The elastic modulus (G') of these samples was much higher than the visco...

  16. The sweep-line state space exploration method

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars M.; Mailund, Thomas

    2012-01-01

    The sweep-line method exploits intrinsic progress in concurrent systems to alleviate the state explosion problem in explicit state model checking. The concept of progress makes it possible to delete states from the memory during state space exploration and thereby reduce peak memory usage...

  17. The SWEEP concept: a cost-benefit analysis

    NARCIS (Netherlands)

    Kempenaar, C.; Dijk, van C.J.

    2006-01-01

    SWEEP demonstrates a new concept for weed control on hard surfaces. The concept aims at a substantial reduction of herbicide emission to surface and soil waters. The concept is a decision support system with protocols that guarantee a substantial reduction in herbicide use and emission. Only a

  18. Multiscale mapping of frequency sweep rate in mouse auditory cortex.

    Science.gov (United States)

    Issa, John B; Haeffele, Benjamin D; Young, Eric D; Yue, David T

    2017-02-01

    Functional organization is a key feature of the neocortex that often guides studies of sensory processing, development, and plasticity. Tonotopy, which arises from the transduction properties of the cochlea, is the most widely studied organizational feature in auditory cortex; however, in order to process complex sounds, cortical regions are likely specialized for higher order features. Here, motivated by the prevalence of frequency modulations in mouse ultrasonic vocalizations and aided by the use of a multiscale imaging approach, we uncover a functional organization across the extent of auditory cortex for the rate of frequency modulated (FM) sweeps. In particular, using two-photon Ca(2+) imaging of layer 2/3 neurons, we identify a tone-insensitive region at the border of AI and AAF. This central sweep region behaves fundamentally differently from nearby neurons in AI and AII, responding preferentially to fast FM sweeps but not to tones or bandlimited noise. Together these findings define a second dimension of organization in the mouse auditory cortex for sweep rate complementary to that of tone frequency.

  19. Improved volumetric imaging in tomosynthesis using combined multiaxial sweeps.

    Science.gov (United States)

    Gersh, Jacob A; Wiant, David B; Best, Ryan C M; Bennett, Marcus C; Munley, Michael T; King, June D; McKee, Mahta M; Baydush, Alan H

    2010-09-03

    This study explores the volumetric reconstruction fidelity attainable using tomosynthesis with a kV imaging system which has a unique ability to rotate isocentrically and with multiple degrees of mechanical freedom. More specifically, we seek to investigate volumetric reconstructions by combining multiple limited-angle rotational image acquisition sweeps. By comparing these reconstructed images with those of a CBCT reconstruction, we can gauge the volumetric fidelity of the reconstructions. In surgical situations, the described tomosynthesis-based system could provide high-quality volumetric imaging without requiring patient motion, even with rotational limitations present. Projections were acquired using the Digital Integrated Brachytherapy Unit, or IBU-D. A phantom was used which contained several spherical objects of varying contrast. Using image projections acquired during isocentric sweeps around the phantom, reconstructions were performed by filtered backprojection. For each image acquisition sweep configuration, a contrasting sphere is analyzed using two metrics and compared to a gold standard CBCT reconstruction. Since the intersection of a reconstructed sphere and an imaging plane is ideally a circle with an eccentricity of zero, the first metric presented compares the effective eccentricity of intersections of reconstructed volumes and imaging planes. As another metric of volumetric reconstruction fidelity, the volume of one of the contrasting spheres was determined using manual contouring. By comparing these manually delineated volumes with a CBCT reconstruction, we can gauge the volumetric fidelity of reconstructions. The configuration which yielded the highest overall volumetric reconstruction fidelity, as determined by effective eccentricities and volumetric contouring, consisted of two orthogonally-offset 60° L-arm sweeps and a single C-arm sweep which shared a pivot point with one the L-arm sweeps. When compared to a similar configuration that

  20. Is membrane sweeping beneficial at the initiation of labor induction?

    Science.gov (United States)

    Al-Harmi, Jehad; Chibber, Rachana; Fouda, Mohamed; Mohammed, Zeinab K; El-Saleh, Eyad; Tasneem, Asiya

    2015-07-01

    To determine whether cervical membrane sweeping during labor induction is beneficial. Outcomes of labor after induction in pregnant women at term were compared in a randomized trial. Women were assigned to having their membranes "swept" or "not swept" at the initiation of labor induction. We recruited a total of 870 women of which 70 were excluded. There were 400 nullipara (Group A) [198 "swept", 202 "not swept"] and 400 multiparas (Group B) (201 "swept" and 199 "not swept"]. Among group A who received intravaginal prostaglandin (PG) E2, those who had simultaneous sweeping had significantly shorter mean induction-labor interval (12.9 ± 1.3 versus 16.2 ± 1.1 hours, p = 0.046), lower mean dose of oxytocin (6.6 ± 0.6 versus 10.11 ± 1.4 mU/minute, p = 0.01), and increased normal delivery rates (vaginal delivery 82.8% versus 58.6%, p = 0.01). Sweeping also had a favorable effect on nulliparas who had ARM and received oxytocin alone (mean induction-labor interval 5.9 ± 2.9 versus 10.9 ± 2.6 hours p = 0.04, mean maximum dose of oxytocin 9.8 ± 1.1 versus 15.2 ± 1.1 mU/min, p = 0.01). These results were restricted to women with unfavorable cervix in Group A those who had membrane sweeping. Membrane sweeping, has beneficial effects on labor and delivery, which is limited to nulliparas with unfavorable cervix requiring PGE2 or Oxytocin alone.

  1. A Parallel Sweeping Preconditioner for Heterogeneous 3D Helmholtz Equations

    KAUST Repository

    Poulson, Jack

    2013-05-02

    A parallelization of a sweeping preconditioner for three-dimensional Helmholtz equations without large cavities is introduced and benchmarked for several challenging velocity models. The setup and application costs of the sequential preconditioner are shown to be O(γ2N4/3) and O(γN logN), where γ(ω) denotes the modestly frequency-dependent number of grid points per perfectly matched layer. Several computational and memory improvements are introduced relative to using black-box sparse-direct solvers for the auxiliary problems, and competitive runtimes and iteration counts are reported for high-frequency problems distributed over thousands of cores. Two open-source packages are released along with this paper: Parallel Sweeping Preconditioner (PSP) and the underlying distributed multifrontal solver, Clique. © 2013 Society for Industrial and Applied Mathematics.

  2. Sweep Distortion Removal from THz Images via Blind Demodulation

    CERN Document Server

    Aghasi, Alireza; Redo-Sanchez, Albert; Romberg, Justin; Raskar, Ramesh

    2016-01-01

    Heavy sweep distortion induced by alignments and inter-reflections of layers of a sample is a major burden in recovering 2D and 3D information in time resolved spectral imaging. This problem cannot be addressed by conventional denoising and signal processing techniques as it heavily depends on the physics of the acquisition. Here we propose and implement an algorithmic framework based on low-rank matrix recovery and alternating minimization that exploits the forward model for THz acquisition. The method allows recovering the original signal in spite of the presence of temporal-spatial distortions. We address a blind-demodulation problem, where based on several observations of the sample texture modulated by an undesired sweep pattern, the two classes of signals are separated. The performance of the method is examined in both synthetic and experimental data, and the successful reconstructions are demonstrated. The proposed general scheme can be implemented to advance inspection and imaging applications in THz ...

  3. (Test and gather data on sweep spike combination tillage tool)

    Energy Technology Data Exchange (ETDEWEB)

    Lukach, J.

    1992-06-19

    This summary presents the data accumulated to date with only brief comment. It is prepared with the intent that the viewers will offer advice on terminology, data presentation, methods and other. The year end analysis will detail changes in the data due to the tillage treatments. The data is incomplete due to equipment problems and time limitations due to the wet fall and early freeze up. The trial was not completed due to our inability to get the Mikkelsen Chisel Plow Shovel (MCP), a 16 inch sweep with an anhydrous knife, to penetrate untilled land. The MCP shovel penetrated to deep on plowed ground and pulled so hard that the front wheels of our JD4440 tractor were jerked off the ground. The Standard Chisel Plow Shovels (SCP), a 16 inch sweep, worked well and the data is included.

  4. Sweep-twist adaptive rotor blade : final project report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashwill, Thomas D.

    2010-02-01

    Knight & Carver was contracted by Sandia National Laboratories to develop a Sweep Twist Adaptive Rotor (STAR) blade that reduced operating loads, thereby allowing a larger, more productive rotor. The blade design used outer blade sweep to create twist coupling without angled fiber. Knight & Carver successfully designed, fabricated, tested and evaluated STAR prototype blades. Through laboratory and field tests, Knight & Carver showed the STAR blade met the engineering design criteria and economic goals for the program. A STAR prototype was successfully tested in Tehachapi during 2008 and a large data set was collected to support engineering and commercial development of the technology. This report documents the methodology used to develop the STAR blade design and reviews the approach used for laboratory and field testing. The effort demonstrated that STAR technology can provide significantly greater energy capture without higher operating loads on the turbine.

  5. Multibeam fiber laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Hansen, Klaus Schütt; Nielsen, Jakob Skov

    2009-01-01

    The appearance of the high power high brilliance fiber laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating Cutting laser, the CO2 laser. However, quality problems in fiber-laser...... cutting have until now limited its application to metal cutting. In this paper the first results of proof-of-principle Studies applying a new approach (patent pending) for laser cutting with high brightness and short wavelength lasers will be presented. In the approach, multibeam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from two single mode fiber lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W...

  6. Multibeam Fibre Laser Cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    The appearance of the high power high brilliance fibre laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating cutting laser, the CO2-laser. However, quality problems in fibre-laser...... cutting have until now limited its application in metal cutting. In this paper the first results of proof-of-principle studies applying a new approach (patent pending) for laser cutting with high brightness short wavelength lasers will be presented. In the approach, multi beam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from 2 single mode fibre lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W of single...

  7. Ultra fast frequency sweep heterodyne reflectometer on the Tore Supra tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, Ph.; Clairet, F.; Chareau, J.M.; Paume, M.; Laviron, C

    1998-09-01

    A new O-Mode dual frequency heterodyne reflectometer has been installed on Tore Supra, introducing outstanding improvement of the phase determination due high dynamic heterodyne detection, and ultra fast sweeps capabilities (10 {mu}s) provided by the solid state source HTOs. This system operates with O-mode electric field polarization in the range of 26 - 36 GHz and has been designed for density profile measurements. The reflectometer launches simultaneously into the plasma two frequencies separated by 320 MHz. The heterodyne detection improves the dynamic, up to 60 db, and is associated with an I.Q. detection to allow separate analysis of amplitude and phase of each reflected signals of both probing waves. Therefore, to calculate the density profile, the group delay can be defined in two different ways: from the derivative of the absolute phase of one of the two probing waves or by calculating the phase difference between the two probing waves. It is explained how ultra fast sweep operations (down to 10 {mu}s) significantly reduce the influence of the plasma turbulence upon the phase measurements. It is also pointed out the importance of filtering carefully the detected signal in order to keep only the information coming from the reflection at the cut-off and to get rid of parasitic reflections. It is shown that the phase difference technique does not remove completely fluctuations such as long radial correlation MHD perturbation. Density profiles determined by the heterodyne reflectometer are in good agreement with the measurements from the other diagnostics of Tore Supra. (author) 16 refs.

  8. Multiple mechanisms shape FM sweep rate selectivity: complementary or redundant?

    Directory of Open Access Journals (Sweden)

    Zoltan M Fuzessery

    2012-08-01

    Full Text Available Auditory neurons in the inferior colliculus (IC of the pallid bat have strong rate selective responses to downward frequency modulated (FM sweeps attributable to the spectrotemporal pattern of their echolocation call (a brief FM pulse. Several mechanisms are known to shape FM rate selectivity within the pallid bat IC. Here we explore how two mechanisms, stimulus duration and high-frequency inhibition (HFI, can interact to shape FM rate selectivity within the same neuron. Results from extracellular recordings indicated that a derived duration-rate function (based on tonal response was highly predictive of the shape of the FM rate response. Longpass duration selectivity for tones was predictive of slowpass rate selectivity for FM sweeps, both of which required long stimulus durations and remained intact following iontophoretic blockade of inhibitory input. Bandpass duration selectivity for tones, sensitive to only a narrow range of tone durations, was predictive of bandpass rate selectivity for FM sweeps. Conversion of the tone duration response from bandpass to longpass after blocking inhibition was coincident with a change in FM rate selectivity from bandpass to slowpass indicating an active inhibitory component to the formation of bandpass selectivity. Independent of the effect of duration tuning on FM rate selectivity, the presence of HFI acted as a fastpass FM rate filter by suppressing slow FM sweep rates. In cases where both mechanisms were present, both had to be eliminated, by removing inhibition, before bandpass FM rate selectivity was affected. It is unknown why the auditory system utilizes multiple mechanisms capable of shaping identical forms of FM rate selectivity though it may represent distinct but convergent modes of neural signaling directed at shaping response selectivity for important biologically relevant sounds.

  9. Sweep-net sampling acorns in forested wetlands

    Science.gov (United States)

    Mitch D. Weegman; Richard M. Kaminski; Guiming Wang; Michael L. Schummer; Andrew W. Ezell; Theodor D. Leininger

    2010-01-01

    We are unaware of any previous studies to evaluate using a sweep net to estimate abundance of red oak acorns (Quercus spp.) after they fall from tree crowns, sink to the ground in flooded bottomlands (i.e., sound acorns), and become potential food for animals or propagules for seedlings. We placed known numbers of white-painted red oak acorns of 3 size classes and used...

  10. Flexible Laser Metal Cutting

    DEFF Research Database (Denmark)

    Villumsen, Sigurd; Jørgensen, Steffen Nordahl; Kristiansen, Morten

    2014-01-01

    This paper describes a new flexible and fast approach to laser cutting called ROBOCUT. Combined with CAD/CAM technology, laser cutting of metal provides the flexibility to perform one-of-a-kind cutting and hereby realises mass production of customised products. Today’s laser cutting techniques...... possess, despite their wide use in industry, limitations regarding speed and geometry. Research trends point towards remote laser cutting techniques which can improve speed and geometrical freedom and hereby the competitiveness of laser cutting compared to fixed-tool-based cutting technology...... such as punching. This paper presents the concepts and preliminary test results of the ROBOCUT laser cutting technology, a technology which potentially can revolutionise laser cutting....

  11. Cutting state identification

    Energy Technology Data Exchange (ETDEWEB)

    Berger, B.S.; Minis, I.; Rokni, M. [Univ. of Maryland, College Park, MD (United States)] [and others

    1997-12-31

    Cutting states associated with the orthogonal cutting of stiff cylinders are identified through an analysis of the singular values of a Toeplitz matrix of third order cumulants of acceleration measurements. The ratio of the two pairs of largest singular values is shown to differentiate between light cutting, medium cutting, pre-chatter and chatter states. Sequences of cutting experiments were performed in which either depth of cut or turning frequency was varied. Two sequences of experiments with variable turning frequency and five with variable depth of cut, 42 cutting experiments in all, provided a database for the calculation of third order cumulants. Ratios of singular values of cumulant matrices find application in the analysis of control of orthogonal cutting.

  12. Simulation of Laser Cutting

    Science.gov (United States)

    Schulz, Wolfgang; Nießen, Markus; Eppelt, Urs; Kowalick, Kerstin

    Laser cutting is a thermal separation process widely used in shaping and contour cutting applications. There are, however, gaps in understanding the dynamics of the process, especially issues related to cut quality. This work describes the advances in fundamental physical modelling and process monitoring of laser cutting, as well as time varying processes such as contour cutting. Diagnosis of ripple and dross formation is advanced to observe the melt flow and its separation simultaneously as well as the spatial shape of the cut kerf.

  13. Tycho 2: A Proxy Application for Kinetic Transport Sweeps

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Charles Kristopher [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Computer, Computational, and Statistical Sciences Division; Warsa, James S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Computer, Computational, and Statistical Sciences Division

    2016-09-14

    Tycho 2 is a proxy application that implements discrete ordinates (SN) kinetic transport sweeps on unstructured, 3D, tetrahedral meshes. It has been designed to be small and require minimal dependencies to make collaboration and experimentation as easy as possible. Tycho 2 has been released as open source software. The software is currently in a beta release with plans for a stable release (version 1.0) before the end of the year. The code is parallelized via MPI across spatial cells and OpenMP across angles. Currently, several parallelization algorithms are implemented.

  14. FUV Focus Sweep Exploratory Program for COS at LP4

    Science.gov (United States)

    Sonnentrucker, Paule; Fox, Andrew; Penton, Steve; Oliveira, Cristina; Roman-Duval, Julia; Sahnow, David

    2017-08-01

    As part of the exploratory phase of the move of COS/FUV operations to Lifetime Position 4 (LP4), we designed program 14527 to measure changes in the focus offsets required to optimize spectral resolution at the prospective LP4 position (-5.02" from LP1 in cross-dispersion direction). Following the successful strategy established in program LENA2 (P13635, LP3 move), we executed one focus sweep using the G130M/1222 configuration (FUVB only) and two sweeps using the G130M/1309 configuration (FUVA and FUVB treated separately). The target Feige 48 was observed in this program for a total of 4 external orbits. As previously, we used an auto-correlation method to derive the focus offsets relative to LP3 that maximize spectral resolution at LP4 for the G130M/1309 and G130M/1222 settings. We find that a focus offset value of +40 steps relative to LP3 maximizes spectral resolution at LP4 for the G130M/1309 configuration (FUVA and FUVB combined). For G130M/1222 (FUVB only), the ado! pted focus offset value that maximizes spectral resolution at LP4 is of +142 steps from the relative to LP3. These values were patched into a FSW update to LV0058 on December 17, 2016 (2016.354) and were permanently installed as part of LV0059 on May 8, 2017 (2017.128). This is a partner ISR to 2017-17.

  15. Evaluation and Enhancement of Carbon Dioxide Flooding Through Sweep Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Richard

    2009-09-30

    Carbon dioxide displacement is a common improved recovery method applied to light oil reservoirs (30-45{degrees}API). The economic and technical success of CO{sub 2} floods is often limited by poor sweep efficiency or large CO{sub 2} utilization rates. Projected incremental recoveries for CO{sub 2} floods range from 7% to 20% of the original oil in place; however, actual incremental recoveries range from 9% to 15% of the original oil in place, indicating the potential for significant additional recoveries with improved sweep efficiency. This research program was designed to study the effectiveness of carbon dioxide flooding in a mature reservoir to identify and develop methods and strategies to improve oil recovery in carbon dioxide floods. Specifically, the project has focused on relating laboratory, theoretical and simulation studies to actual field performance in a CO{sub 2} flood in an attempt to understand and mitigate problems of areal and vertical sweep efficiency. In this work the focus has been on evaluating the status of existing swept regions of a mature CO{sub 2} flood and developing procedures to improve the design of proposed floods. The Little Creek Field, Mississippi has been studied through laboratory, theoretical, numerical and simulation studies in an attempt to relate performance predictions to historical reservoir performance to determine sweep efficiency, improve the understanding of the reservoir response to CO{sub 2} injection, and develop scaling methodologies to relate laboratory data and simulation results to predicted reservoir behavior. Existing laboratory information from Little Creek was analyzed and an extensive amount of field data was collected. This was merged with an understanding of previous work at Little Creek to generate a detailed simulation study of two portions of the field – the original pilot area and a currently active part of the field. This work was done to try to relate all of this information to an understanding

  16. Device for cutting protrusions

    Science.gov (United States)

    Bzorgi, Fariborz M.

    2011-07-05

    An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade. The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.

  17. Potential flow calculations and preliminary wing design in support of an NLF variable sweep transition flight experiment

    Science.gov (United States)

    Waggoner, E. G.; Phillips, P. S.; Viken, J. K.; Davis, W. H.

    1985-01-01

    NASA Langley and NASA Ames-Dryden have defined a variable-sweep transition-flight experiment utilizing the F-14 aircraft to enhance understanding of the interaction of crossflow and Tollmien-Schlichting instabilities on a laminar-boundary-layer transition. The F-14 wing outer panel will be modified to generate favorable pressure gradients on the upper wing surface over a wide range of flight conditions. Extensive computations have been performed using two-dimensional and three-dimensional transonic analysis codes. Flight-test and computational data are compared and shown to validate the applicability of the three-dimensional codes (WBPPW and TAWFIVE). In addition, results from two preliminary glove designs derived from two different approaches to the design problem are presented. Advantages and disadvantages of each approach are identified, and it is concluded that coupling an analysis code with an automated design procedure yields a powerful code with distinct advantages over a 'cut-and-dry' approach.

  18. Graphs of Plural Cuts

    CERN Document Server

    Dosen, K

    2011-01-01

    Plural (or multiple-conclusion) cuts are inferences made by applying a structural rule introduced by Gentzen for his sequent formulation of classical logic. As singular (single-conclusion) cuts yield trees, which underlie ordinary natural deduction derivations, so plural cuts yield graphs of a more complicated kind, related to trees, which this paper defines. Besides the inductive definition of these oriented graphs, which is based on sequent systems, a non-inductive, graph-theoretical, combinatorial, definition is given, and to reach that other definition is the main goal of the paper. As trees underlie multicategories, so the graphs of plural cuts underlie polycategories. The graphs of plural cuts are interesting in particular when the plural cuts are appropriate for sequent systems without the structural rule of permutation, and the main body of the paper deals with that matter. It gives a combinatorial characterization of the planarity of the graphs involved.

  19. Laser Cutting, Development Trends

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    1999-01-01

    In this paper a short review of the development trends in laser cutting will be given.The technology, which is the fastest expanding industrial production technology will develop in both its core market segment: Flat bed cutting of sheet metal, as it will expand in heavy industry and in cutting o...... of 3-dimensional shapes.The CO2-laser will also in the near future be the dominating laser source in the market, although the new developments in ND-YAG-lasers opens for new possibilities for this laser type.......In this paper a short review of the development trends in laser cutting will be given.The technology, which is the fastest expanding industrial production technology will develop in both its core market segment: Flat bed cutting of sheet metal, as it will expand in heavy industry and in cutting...

  20. Laser cutting plastic materials

    Energy Technology Data Exchange (ETDEWEB)

    Van Cleave, R.A.

    1980-08-01

    A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

  1. Sweeping Preconditioner for the Helmholtz Equation: Artificial Perfectly Matched Layers

    CERN Document Server

    Engquist, Björn

    2010-01-01

    This paper introduces a new sweeping preconditioner for the iterative solution of the variable coefficient Helmholtz equation in two and three dimensions. The algorithms follow the general structure of constructing an approximate $LDL^t$ factorization by eliminating the unknowns layer by layer starting from an absorbing layer. The central idea of this paper is to approximate the Schur complement matrices of the factorization using artificial perfectly matched layers (PMLs) introduced in the interior of the domain. Applying each Schur complement matrix is equivalent to solving a quasi-1D problem with a banded LU factorization in the 2D case and to solving a quasi-2D problem with a multifrontal method in the 3D case. The resulting preconditioner has linear application cost and the preconditioned iterative solver converges in a number of iterations that scales at most logarithmically with the number of unknowns. Numerical results are presented in both two and three dimensions to demonstrate the efficiency of thi...

  2. Integrated circuit electrometer and sweep circuitry for an atmospheric probe

    Science.gov (United States)

    Zimmerman, L. E.

    1971-01-01

    The design of electrometer circuitry using an integrated circuit operational amplifier with a MOSFET input is described. Input protection against static voltages is provided by a dual ultra low leakage diode or a neon lamp. Factors affecting frequency response leakage resistance, and current stability are discussed, and methods are suggested for increasing response speed and for eliminating leakage resistance and current instabilities. Based on the above, two practical circuits, one having a linear response and the other a logarithmic response, were designed and evaluated experimentally. The design of a sweep circuit to implement mobility measurements using atmospheric probes is presented. A triangular voltage waveform is generated and shaped to contain a step in voltage from zero volts in both positive and negative directions.

  3. Elementary calculation of clip connections with incomplete sweep of shaft

    Directory of Open Access Journals (Sweden)

    Ivan P. Shatsky

    2015-06-01

    Full Text Available The article describes promising structures of clip (screw and friction connections with incomplete sweep of shaft used in machines and mechanisms for the oil and gas industry. The contact problems of interaction between semi-hubs and shaft for the symmetric and asymmetric connections are formulated. For structures that are asymmetric relatively the joint bolt two types of interaction are investigated: with and without lateral displacement. Based on a priori assumption about the distribution laws of contact pressure accepted in traditional courses of “Machine Details” an engineering method for calculating of clip connections is developed. Herewith different types of details coupling (with a gap, matched, with tension correspond to concentrated, cosine and sustainable (linear distributions of contact stresses. There are determined an analytical dependences of boundary points and breakloose force on spanning angles, bolt tightening force and tribological properties of joined parts of subassembly.

  4. Superluminal Spot Pair Events in Astronomical Settings: Sweeping Beams

    CERN Document Server

    Nemiroff, Robert J

    2014-01-01

    Sweeping beams of light can cast spots moving with superluminal speeds across scattering surfaces. Such faster-than-light speeds are well-known phenomena that do not violate special relativity. It is shown here that under certain circumstances, superluminal spot pair creation and annihilation events can occur that provide unique information to observers. These spot pair events are {\\it not} particle pair events -- they are the sudden creation or annihilation of a pair of relatively illuminated spots on a scattering surface. Real spot pair illumination events occur unambiguously on the scattering surface when spot speeds diverge, while virtual spot pair events are observer dependent and perceived only when real spot radial speeds cross the speed of light. Specifically, a virtual spot pair creation event will be observed when a real spot's speed toward the observer drops below $c$, while a virtual spot pair annihilation event will be observed when a real spot's radial speed away from the observer rises above $c...

  5. Determination of Pesticide Ethion by Linear Sweep Stripping Voltammetry

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The presence of the pesticide ethion was determined using an electroanalytical method, i. e. , linear sweep stripping voltammetry at a hanging mercury drop electrode in the Britton-Robbinson buffer with pH = 8. 36, based on its reduction peak observed at - 690 mV following its alkaline hydrolysis. The experimental parameters, namely, the preconcentration potential, the preconcentration time, and the scan rate were investigated and -300 mV (vs. Ag/AgCl), 270 s, and 100 mV/s were selected as the optimal values, respectively. The linear relationship between the peak current and the concentration was found to be in the range of 0. 02-0. 16 mg/L, with a detection limit of 0.0087 mg/L. The proposed method was applied to the determination of ethion in spiked vegetable and fruit samples via a preextraction with anhydrous ethanol.

  6. A double-sweeping preconditioner for the Helmholtz equation

    Science.gov (United States)

    Eslaminia, Mehran; Guddati, Murthy N.

    2016-06-01

    A new preconditioner is developed to increase the efficiency of iterative solution of the Helmholtz equation. The key idea of the proposed preconditioner is to split the domain of interest into smaller subdomains and sequentially approximate the forward and backward components of the solution. The sequential solution is facilitated by approximate interface conditions that ignore the effect of multiple reflections. The efficiency of the proposed method is tested using various 2-D heterogeneous media. We observe that the proposed preconditioner results in good convergence, with number of iterations growing very slowly with increasing frequency. We also note that the mesh size and number of subdomains do not affect the convergence rate. Finally, we find that the overall computational time is much smaller than that of the sweeping preconditioner.

  7. Ultrasonic Cutting of Foods

    Science.gov (United States)

    Schneider, Yvonne; Zahn, Susann; Rohm, Harald

    In the field of food engineering, cutting is usually classified as a mechanical unit operation dealing with size reduction by applying external forces on a bulk product. Ultrasonic cutting is realized by superpositioning the macroscopic feed motion of the cutting device or of the product with a microscopic vibration of the cutting tool. The excited tool interacts with the product and generates a number of effects. Primary energy concentration in the separation zone and the modification of contact friction along the tool flanks arise from the cyclic loading and are responsible for benefits such as reduced cutting force, smooth cut surface, and reduced product deformation. Secondary effects such as absorption and cavitation originate from the propagation of the sound field in the product and are closely related to chemical and physical properties of the material to be cut. This chapter analyzes interactions between food products and ultrasonic cutting tools and relates these interactions with physical and chemical product properties as well as with processing parameters like cutting velocity, ultrasonic amplitude and frequency, and tool design.

  8. Simulation of Sweep-Jet Flow Control, Single Jet and Full Vertical Tail

    Science.gov (United States)

    Childs, Robert E.; Stremel, Paul M.; Garcia, Joseph A.; Heineck, James T.; Kushner, Laura K.; Storms, Bruce L.

    2016-01-01

    This work is a simulation technology demonstrator, of sweep jet flow control used to suppress boundary layer separation and increase the maximum achievable load coefficients. A sweep jet is a discrete Coanda jet that oscillates in the plane parallel to an aerodynamic surface. It injects mass and momentum in the approximate streamwise direction. It also generates turbulent eddies at the oscillation frequency, which are typically large relative to the scales of boundary layer turbulence, and which augment mixing across the boundary layer to attack flow separation. Simulations of a fluidic oscillator, the sweep jet emerging from a nozzle downstream of the oscillator, and an array of sweep jets which suppresses boundary layer separation are performed. Simulation results are compared to data from a dedicated validation experiment of a single oscillator and its sweep jet, and from a wind tunnel test of a full-scale Boeing 757 vertical tail augmented with an array of sweep jets. A critical step in the work is the development of realistic time-dependent sweep jet inflow boundary conditions, derived from the results of the single-oscillator simulations, which create the sweep jets in the full-tail simulations. Simulations were performed using the computational fluid dynamics (CFD) solver Overow, with high-order spatial discretization and a range of turbulence modeling. Good results were obtained for all flows simulated, when suitable turbulence modeling was used.

  9. Sweeping a molecular Bose-Einstein condensate across a Feshbach resonance

    NARCIS (Netherlands)

    Haque, M.; Stoof, H.T.C.

    2007-01-01

    We consider the dissociation of a molecular Bose-Einstein condensate during a magnetic-field sweep through a Feshbach resonance that starts on the molecular side of the resonance and ends on the atomic side. In particular, we determine the energy distribution of the atoms produced after the sweep. W

  10. Saving Seal Cutting

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    On April 20, the graduation ceremony of China’s seal-cutting art postgraduates and visiting experts from the Institute of Seal Cutting Art under the China Art Academy was held in Beijing. On the same day, the exhibition of the works of the teachers and graduates of the institute was also held.

  11. Cutting Class Harms Grades

    Science.gov (United States)

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  12. Fundamentals of cutting.

    Science.gov (United States)

    Williams, J G; Patel, Y

    2016-06-06

    The process of cutting is analysed in fracture mechanics terms with a view to quantifying the various parameters involved. The model used is that of orthogonal cutting with a wedge removing a layer of material or chip. The behaviour of the chip is governed by its thickness and for large radii of curvature the chip is elastic and smooth cutting occurs. For smaller thicknesses, there is a transition, first to plastic bending and then to plastic shear for small thicknesses and smooth chips are formed. The governing parameters are tool geometry, which is principally the wedge angle, and the material properties of elastic modulus, yield stress and fracture toughness. Friction can also be important. It is demonstrated that the cutting process may be quantified via these parameters, which could be useful in the study of cutting in biology.

  13. Research of nonlinear simulation on sweep voltage of streak tube imaging lidar

    Science.gov (United States)

    Zhai, Qian; Han, Shao-kun; Zhai, Yu; Lei, Jie-yu; Yao, Jian-feng

    2016-10-01

    In order to study the influence of nonlinear sweep voltage on the range accuracy of streak tube imaging lidar, a nonlinear distance model of streak tube is proposed. The model of the parallel-plate deflection system is studied, and the mathematical relation between the sweep voltage and the position of the image point on the screen is obtained based on the movement rule of phoelectron. And the mathematical model of the sweep voltage is established on the basis of its principle. The simulation of streak image is carried out for the selected staircase target, the range image of the target can be reconstructed by extremum method. Comparing reconstruction result and actual target, the range accuracy caused by the nonlinear sweep voltage is obtained. The curve of the errors varying with target ranges is also obtained. And the range accuracy of the system is analyzed by the means of changing the parameter relate to sweep time.

  14. Online Cake Cutting

    CERN Document Server

    Walsh, Toby

    2010-01-01

    We propose an online form of the cake cutting problem. This models situations where players arrive and depart during the process of dividing a resource. We show that well known fair division procedures like cut-and-choose and the Dubins-Spanier moving knife procedure can be adapted to apply to such online problems. We propose some desirable properties that online cake cutting procedures might possess like online forms of proportionality and envy-freeness, and identify which properties are in fact possessed by the different online cake procedures.

  15. Experimental testing of exchangeable cutting inserts cutting ability

    OpenAIRE

    Čep, Robert; Janásek, Adam; Čepová Lenka; Petrů, Jana; Ivo HLAVATÝ; Car, Zlatan; Hatala, Michal

    2013-01-01

    The article deals with experimental testing of the cutting ability of exchangeable cutting inserts. Eleven types of exchangeable cutting inserts from five different manufacturers were tested. The tested cutting inserts were of the same shape and were different especially in material and coating types. The main aim was both to select a suitable test for determination of the cutting ability of exchangeable cutting inserts and to design such testing procedure that could make it possible...

  16. Beautiful heat: a master chimney sweep talks about burning issues

    Energy Technology Data Exchange (ETDEWEB)

    Hederich, M.P.

    2001-07-01

    Fire has played a major role in mankind's life from the beginning. Used for heating and cooking, its various uses have evolved to include controlled explosions shortly after the development of gunpowder, and the generation of electricity made other uses possible. The author, a certified solid fuel technician and chimney sweep, as well as a licensed technician for natural gas and propane, has written this book to enable the reader to enjoy safe and dependable wood fires year round by taking the necessary steps. The first recommendation made is against the homeowner installing himself/herself any solid fuel system. It is a job better left to the professionals, considering the substantial product and regulation knowledge and experience required. Specific information related to solid fuel burning technology is included in this book, to be used as a guide. Part 1 of the book deals with the fuel, touching on issues such as energy and the environment, wood combustion and air pollution, buying firewood, wood ashes, cleaning your heating system and others. Part 2 is devoted to the heating system. It introduces topics ranging from the systems advisor to the location and installation of the system, the principles of space heating, high efficiency wood burning, inspections, to name just a few. 22 refs., tabs., figs.

  17. Persistent Robotic Tasks: Monitoring and Sweeping in Changing Environments

    CERN Document Server

    Smith, Stephen L; Rus, Daniela

    2011-01-01

    We present controllers that enable mobile robots to persistently monitor or sweep a changing environment. The changing environment is modeled as a field which grows in locations that are not within range of a robot, and decreases in locations that are within range of a robot. We assume that the robots travel on given closed paths. The speed of each robot along its path is controlled to prevent the field from growing unbounded at any location. We consider the space of speed controllers that can be parametrized by a finite set of basis functions. For a single robot, we develop a linear program that is guaranteed to compute a speed controller in this space to keep the field bounded, if such a controller exists. Another linear program is then derived whose solution is the speed controller that minimizes the maximum field value over the environment. We extend our linear program formulation to develop a multi-robot controller that keeps the field bounded. The multi-robot controller has the unique feature that it do...

  18. High Speed Computational Ghost Imaging via Spatial Sweeping

    Science.gov (United States)

    Wang, Yuwang; Liu, Yang; Suo, Jinli; Situ, Guohai; Qiao, Chang; Dai, Qionghai

    2017-01-01

    Computational ghost imaging (CGI) achieves single-pixel imaging by using a Spatial Light Modulator (SLM) to generate structured illuminations for spatially resolved information encoding. The imaging speed of CGI is limited by the modulation frequency of available SLMs, and sets back its practical applications. This paper proposes to bypass this limitation by trading off SLM’s redundant spatial resolution for multiplication of the modulation frequency. Specifically, a pair of galvanic mirrors sweeping across the high resolution SLM multiply the modulation frequency within the spatial resolution gap between SLM and the final reconstruction. A proof-of-principle setup with two middle end galvanic mirrors achieves ghost imaging as fast as 42 Hz at 80 × 80-pixel resolution, 5 times faster than state-of-the-arts, and holds potential for one magnitude further multiplication by hardware upgrading. Our approach brings a significant improvement in the imaging speed of ghost imaging and pushes ghost imaging towards practical applications. PMID:28358010

  19. Fatigue crack growth rate test using a frequency sweep method

    Institute of Scientific and Technical Information of China (English)

    Xun ZHOU; Xiao-li YU

    2008-01-01

    Fatigue crack propagation characteristics of a diesel engine crankshaft are studied by measuring the fatigue crack growth rate using a frequency sweep method on a resonant fatigue test rig. Based on the phenomenon that the system frequency will change when the crack becomes large, this method can be directly applied to a complex component or structure. Finite element analyses (FEAs) are performed to calibrate the relation between the frequency change and the crack size, and to obtain the natural frequency of the test rig and the stress intensity factor (SIF) of growing cracks. The crack growth rate i.e. da/dN-AK of each crack size is obtained by combining the testing-time monitored data and FEA results. The results show that the crack growth rate of engine crankshaft, which is a component with complex geometry and special surface treatment, is quite different from that of a pure material. There is an apparent turning point in the Paris's crack partition. The cause of the fatigue crack growth is also dis-cussed.

  20. Testing Of Choiced Ceramics Cutting Tools At Irregular Interrupted Cut

    Science.gov (United States)

    Kyncl, Ladislav; Malotová, Šárka; Nováček, Pavel; Nicielnik, Henryk; Šoková, Dagmar; Hemžský, Pavel; Pitela, David; Holubjak, Jozef

    2015-12-01

    This article discusses the test of removable ceramic cutting inserts during machining irregular interrupted cut. Tests were performed on a lathe, with the preparation which simulated us the interrupted cut. By changing the number of plates mounted in a preparation it simulate us a regular or irregular interrupted cut. When with four plates it was regular interrupted cut, the remaining three variants were already irregular cut. It was examined whether it will have the irregular interrupted cutting effect on the insert and possibly how it will change life of inserts during irregular interrupted cut (variable delay between shocks).

  1. Investigations on Low Speed Axial Compressor with Forward and Backward Sweep

    Institute of Scientific and Technical Information of China (English)

    M.Govardhan; O.G.Krishna Kumar; N.Sitaram

    2007-01-01

    In the recent past, experimental studies have shown some advantages of blade lean and sweep in axial compressors. As most of the experimental results are combined with other features, it is difficult to determine the effect of individual parameters on the performance of the compressor. The present numerical studies are aimed at understanding the performance and three-dimensional flow pattern at the exit of swept and unswept rotors. Three rotors, namely; unswept, 200 forward swept and 200 backward swept rotors are analysed with a specific intention of understanding the pattern of the blade boundary layer flow. The analysis was done using a fully three-dimensional viscous CFD code CFX-5. Results indicated reduction in pressure rise with sweep. Backward sweep is detrimental as far as the performance near endwalls is considered. On the other hand total pressure loss in the wake in mid span region is less with backward sweep, which favours its application here. However, backward sweep adversely affects the stall margin. The ability of the forward sweep to deflect the streamlines towards hub gets diminished at low flow rates. Forward sweep changes the streamline pattern in such a way that the suction surface streamlines are deflected towards the hub and the pressure surface streamlines are deflected towards the casing. An opposite behaviour is observed in backward swept rotors.

  2. Load consequences when sweeping blades - A case study of a 5 MW pitch controlled wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Verelst, D.R.S.; Larsen, Torben J.

    2010-08-15

    The generic 5 MW NREL wind turbine model is used in Risoe's aeroelastic simulator HAWC2 to investigate 120 different swept blade configurations (forward and backward sweep). Sensitivity for 2 different controllers is considered as well. Backward sweep results in a pitch to feather torsional moment of the blade, effectively reducing blade twist angles under increased loading. This behaviour results in decreased flap-wise fatigue and extreme loads, an increase for edge-wise fatigue loading and status quo or slight decrease in extreme loads (depending on the controller). Tower base and shaft-end bending moments are reduced as well. Forward sweep leads to an increase in angle of attack under loading. For a pitch controlled turbine this leads to an increase in fatigue and extreme loading in all cases. A controller inflicted instability is present for the more extreme forward swept cases. Due to the shape of considered sweep curves, an inherent and significant increase in torsional blade root bending moment is noted. A boomerang shaped sweep curve is proposed to counteract this problematic increased loading. Controller sensitivity shows that adding sweep affects some loadings differently. Power output is reduced for backward sweep since the blade twist is optimized as a rigid structure, ignoring the torsional deformations which for a swept blade can be significant. (author)

  3. Experimental determination of optimum gutter brush parameters and road sweeping criteria for different types of waste.

    Science.gov (United States)

    Abdel-Wahab, Magd M; Wang, Chong; Vanegas-Useche, Libardo V; Parker, Graham A

    2011-06-01

    The removal ability of gutter brushes for road sweeping for various debris types and different sweeping parameters is studied through experimental tests. The brushing test rig used comprises two commercial gutter brushes, a concrete test bed, and an asphalt test road with a gutter of 0.25 cm width and 10° slope. The brush-surface contact area is determined by sweeping sand on the concrete test bed. Sweeping problems are identified and discussed, and sweeping criteria for the different debris types are suggested. Also, optimum sweeping parameters are proposed for each debris type. In addition, debris removal mechanisms are discussed and analysed. The results indicate that for large heavy debris such as stones and gravel, it is not difficult to achieve large removal forces, because the steel bristles are relatively stiff. Conversely, high removal forces are not needed for particles of millimetre or micron sizes, but bristle curvature has to be appropriate to remove particles from road concavities. Finally, it is found that mud, especially dry mud on a rough surface, is the hardest debris to sweep, requiring a brush with a large tilt angle and a very large penetration to produce large removal forces.

  4. Short-cut math

    CERN Document Server

    Kelly, Gerard W

    1984-01-01

    Clear, concise compendium of about 150 time-saving math short-cuts features faster, easier ways to add, subtract, multiply, and divide. Each problem includes an explanation of the method. No special math ability needed.

  5. Cutting Cakes Correctly

    CERN Document Server

    Hill, Theodore P

    2008-01-01

    Without additional hypotheses, Proposition 7.1 in Brams and Taylor's book "Fair Division" (Cambridge University Press, 1996) is false, as are several related Pareto-optimality theorems of Brams, Jones and Klamler in their 2006 cake-cutting paper.

  6. Measurements of the eigenfunction of reversed shear Alfvén eigenmodes that sweep downward in frequency

    Energy Technology Data Exchange (ETDEWEB)

    Heidbrink, W. W. [University of California Irvine, Irvine, California 92697 (United States); Austin, M. E. [University of Texas at Austin, Austin, Texas 78712 (United States); Spong, D. A. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Tobias, B. J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Van Zeeland, M. A. [General Atomics, San Diego, California 92186 (United States)

    2013-08-15

    Reversed shear Alfvén eigenmodes (RSAEs) usually sweep upward in frequency when the minimum value of the safety factor q{sub min} decreases in time. On rare occasions, RSAEs sweep downward prior to the upward sweep. Electron cyclotron emission measurements show that the radial eigenfunction during the downsweeping phase is similar to the eigenfunction of normal, upsweeping RSAEs.

  7. Membrane Sweeping for Vaginal Birth after Caesarean Section and its Outcome -A Comparative Study.

    Science.gov (United States)

    Ramya, V; Ghose, Seetesh; Pallavee, P

    2015-08-01

    Sweeping of membrane is a method of induction of labour. This is used to avoid prolonged labour. However, there is paucity of data about the use of this method for induction of labour and reducing prolonged labour in pregnancy with previous caesarean section. This study is an effort to find the effect of membrane sweeping in previous caesarean section. To initiate labour in previous LSCS patients by membrane sweeping and maternal outcome. This prospective randomised control study was conducted in Mahatma Gandhi Medical College and Research Institute, Puducherry between January 2011 to June 2012. Seventy five women were randomly assigned to membrane sweeping and seventy five to control. In study group serial membrane sweeping was done once weekly from 39 weeks of gestation until the onset of labour up to 41weeks of gestation. In control group, no intervention up to 41 weeks of gestation. All the cases were monitored by biophysical profile. The primary outcomes measured were number of patients who had onset of labour. The secondary outcome included the successful vaginal delivery, number of membrane sweeping to initiate labour, sweeping to delivery interval and amount of oxytocin required. The onset of labour in study group was 61.3% similar in control group 64% with p 0.736. The mean interval from sweeping to labour onset was 50.15±8 hours. The rate of VBAC was 17.3% in study group in compared to 18.7% in control group and LSCS was 82.7% in study group in compared to 81.3% in control group respectively. The mean gestation age at delivery 40±0.56 weeks for study group compared with 39.92±0.55 weeks for control group. Although membrane sweeping is an easy way of inducing labour, present study failed to demonstrate its beneficial effect on obstetrical outcome.

  8. Laser cutting system

    Science.gov (United States)

    Dougherty, Thomas J

    2015-03-03

    A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

  9. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-07-30

    This is the fourth quarterly progress report for Year-3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between April 1, 2002 and June 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)''; (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions''; (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''; (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  10. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-01-30

    This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  11. Oxygen permeation through perovskitic membranes: The influence of steam in the sweep on the permeation performance

    Directory of Open Access Journals (Sweden)

    Michael Müller

    2016-08-01

    Full Text Available Experimental approaches are employed for the understanding of oxygen permeation through membranes. For the experiments, different oxygen partial pressures are applied to both sides of a BSCF5582 membrane, using synthetic air as feed and vacuum or steam/argon as sweep gas. Beside the partial pressure gradient, the permeation rate depends on the temperature and the membrane thickness. Sufficient permeation rates can be achieved by sweeping the membrane with water vapor (steam instead of a noble gas, which is optimized by ascending water content in the sweep gas. The influence of the steam content on the permeation performance as well as microstructural changes are demonstrated.

  12. Autonomous Planning and Replanning for Mine-Sweeping Unmanned Underwater Vehicles

    Science.gov (United States)

    Gaines, Daniel M.

    2010-01-01

    This software generates high-quality plans for carrying out mine-sweeping activities under resource constraints. The autonomous planning and replanning system for unmanned underwater vehicles (UUVs) takes as input a set of prioritized mine-sweep regions, and a specification of available UUV resources including available battery energy, data storage, and time available for accomplishing the mission. Mine-sweep areas vary in location, size of area to be swept, and importance of the region. The planner also works with a model of the UUV, as well as a model of the power consumption of the vehicle when idle and when moving.

  13. Residual sweeping effects in the swept frame of reference in Kinematic Simulations

    CERN Document Server

    Malik, Nadeem A

    2015-01-01

    It has been suggested that sweeping effects make Lagrangian properties in Kinematic Simulations (KS) unreliable. Here we show through a novel analysis based upon analysing neighbouring particle trajectories in a frame of reference moving with the large energy contining scales that the residual sweeping error in the turbulent pair diffusivity ($K$) in KS is $e_K\\sim dt/\\tau_s$, where $dt$ is the numerical timestep and $\\tau_s$ is the time scale of the sweeping through local eddies. Thus, provided that $dt\\ll \\tau_s$, then $e_K\\ll 1$ and the Lagrangian properties in KS are reliable.

  14. Load Consequences when Sweeping Blades - A Case Study of a 5 MW Pitch Controlled Wind Turbine

    DEFF Research Database (Denmark)

    Verelst, David Robert; Larsen, Torben J.

    of the blade, effectively reducing blade twist angles under increased loading. This behaviour results in decreased flap-wise fatigue and extreme loads, an increase for edge-wise fatigue loading and status quo or slight decrease in extreme loads (depending on the controller). Tower base and shaft-end bending...... of considered sweep curves, an inherent and significant increase in torsional blade root bending moment is noted. A boomerang shaped sweep curve is proposed to counteract this problematic increased loading. Controller sensitivity shows that adding sweep affects some loadings differently. Power output is reduced...

  15. Mechanistic Understanding of Microbial Plugging for Improved Sweep Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Steven Bryant; Larry Britton

    2008-09-30

    Microbial plugging has been proposed as an effective low cost method of permeability reduction. Yet there is a dearth of information on the fundamental processes of microbial growth in porous media, and there are no suitable data to model the process of microbial plugging as it relates to sweep efficiency. To optimize the field implementation, better mechanistic and volumetric understanding of biofilm growth within a porous medium is needed. In particular, the engineering design hinges upon a quantitative relationship between amount of nutrient consumption, amount of growth, and degree of permeability reduction. In this project experiments were conducted to obtain new data to elucidate this relationship. Experiments in heterogeneous (layered) beadpacks showed that microbes could grow preferentially in the high permeability layer. Ultimately this caused flow to be equally divided between high and low permeability layers, precisely the behavior needed for MEOR. Remarkably, classical models of microbial nutrient uptake in batch experiments do not explain the nutrient consumption by the same microbes in flow experiments. We propose a simple extension of classical kinetics to account for the self-limiting consumption of nutrient observed in our experiments, and we outline a modeling approach based on architecture and behavior of biofilms. Such a model would account for the changing trend of nutrient consumption by bacteria with the increasing biomass and the onset of biofilm formation. However no existing model can explain the microbial preference for growth in high permeability regions, nor is there any obvious extension of the model for this observation. An attractive conjecture is that quorum sensing is involved in the heterogeneous bead packs.

  16. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mengjiao Yu; Ramadan Ahmed; Mark Pickell; Len Volk; Lei Zhou; Zhu Chen; Aimee Washington; Crystal Redden

    2003-09-30

    The Quarter began with installing the new drill pipe, hooking up the new hydraulic power unit, completing the pipe rotation system (Task 4 has been completed), and making the SWACO choke operational. Detailed design and procurement work is proceeding on a system to elevate the drill-string section. The prototype Foam Generator Cell has been completed by Temco and delivered. Work is currently underway to calibrate the system. Literature review and preliminary model development for cuttings transportation with polymer foam under EPET conditions are in progress. Preparations for preliminary cuttings transport experiments with polymer foam have been completed. Two nuclear densitometers were re-calibrated. Drill pipe rotation system was tested up to 250 RPM. Water flow tests were conducted while rotating the drill pipe up to 100 RPM. The accuracy of weight measurements for cuttings in the annulus was evaluated. Additional modifications of the cuttings collection system are being considered in order to obtain the desired accurate measurement of cuttings weight in the annular test section. Cutting transport experiments with aerated fluids are being conducted at EPET, and analyses of the collected data are in progress. The printed circuit board is functioning with acceptable noise level to measure cuttings concentration at static condition using ultrasonic method. We were able to conduct several tests using a standard low pass filter to eliminate high frequency noise. We tested to verify that we can distinguish between different depths of sand in a static bed of sand. We tested with water, air and a mix of the two mediums. Major modifications to the DTF have almost been completed. A stop-flow cell is being designed for the DTF, the ACTF and Foam Generator/Viscometer which will allow us to capture bubble images without the need for ultra fast shutter speeds or microsecond flash system.

  17. Improved cutting performance in high power laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2003-01-01

    Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described.......Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described....

  18. Improved cutting performance in high power laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2003-01-01

    Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described.......Recent results in high power laser cutting especially with focus on cutting of mild grade steel types for shipbuilding are described....

  19. Determination of cut front position in laser cutting

    Science.gov (United States)

    Pereira, M.; Thombansen, U.

    2016-07-01

    Laser cutting has a huge importance to manufacturing industry. Laser cutting machines operate with fixed technological parameters and this does not guarantee the best productivity. The adjustment of the cutting parameters during operation can improve the machine performance. Based on a coaxial measuring device it is possible to identify the cut front position during the cutting process. This paper describes the data analysis approach used to determine the cut front position for different feed rates. The cut front position was determined with good resolution, but improvements are needed to make the whole process more stable.

  20. Leading edge sweep effects in generic three-dimensional sidewall compression scramjet inlets

    Science.gov (United States)

    Cozart, Aaron B.; Holland, Scott D.; Trexler, Carl A.; Perkins, John N.

    1992-01-01

    A computational and experimental study of generic 3D sidewall compression inlets is conducted to examine the effects of fore and aft leading edge sweep on the internal shock structure. Inlets with leading edge sweeps of +30 deg and -30 deg with sidewall compression angles of 6 deg were tested in the NASA Langley Mach 4 air tunnel at a geometric contraction ratio of 1.87. The principal difference in performance was determined to be in the mass capture. Spillage was identified as having two components: a pressure induced component and a sweep induced component. It was found that while the direction of the leading edge sweep had a large influence on the spillage, the pressure effects were more important.

  1. Effects of flexibility on aerodynamic performance of delta wings with different sweep angles

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Force measurement and surface oil flow visualization experiments were conducted in a wind tunnel to investigate the effects of flexibility on aerodynamic performance of delta wings with different sweep angles.The experimental results indicate that the maximum lift coefficient is increased and the stall angle is delayed as the sweep angle increases for both rigid and flexible wings.It is also found that the maximum lift coefficients of the flexible wings with a sweep angle from 35° to 50° are higher than those of the rigid ones.The increment of the maximum lift coefficient in particular achieves 32.9% compared with the case without lift enhancement for the 40° flexible delta wing.Moreover,the surface oil flow visualization experiments show that the stall of the flexible wing of the moderate low sweep angle is accompanied by helical flow structure,while the vortex bursting appears on the corresponding rigid wing.

  2. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk, Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2002-10-30

    This is the first quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between July 1, 2002 and Sept. 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System, (b) New Research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings (Task 12), Viscosity of Foam under EPET (Task 9b). (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  3. The effect of leading-edge sweep angle asymmetry on lateral aerodynamics

    Institute of Scientific and Technical Information of China (English)

    ZHAN JingXia; WANG JinJun

    2009-01-01

    Based on the results of force measurement experiment in a low speed wind tunnel,the effect of asymmetrical leading-edge sweep angle on aerodynamic load was investigated with the commonswift's wing model.The wing model was divided into three segments,i.e.,arm wing,hand wingin and hand wingout,and the roll moment produced by the variation of asymmetrical change of wing segment's leading-edge sweep angle was analyzed.

  4. The effect of leading-edge sweep angle asymmetry on lateral aerodynamics

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Based on the results of force measurement experiment in a low speed wind tunnel, the effect of asymmetrical leading-edge sweep angle on aerodynamic load was investigated with the commonswift’s wing model. The wing model was divided into three segments, i.e., arm wing, hand wingin and hand wingout, and the roll moment produced by the variation of asymmetrical change of wing segment’s leading-edge sweep angle was analyzed.

  5. Membrane sweeping at initiation of formal labor induction: a randomized controlled trial.

    Science.gov (United States)

    Tan, Peng Chiong; Jacob, Reena; Omar, Siti Zawiah

    2006-03-01

    To determine the benefit of membrane sweeping at initiation of labor induction in conjunction with formal methods of labor induction. Two hundred seventy-four women at term with a singleton fetus in cephalic presentation and intact membranes were randomly assigned to receive membrane sweeping or no membrane sweeping at initiation of formal labor induction with either dinoprostone pessary or amniotomy. Outcome measures included mode of delivery, induction-to-delivery interval, dinosprostone dose, any oxytocin use and duration of oxytocin use in labor, visual analog score for pain associated with sweeping, and visual analog score for satisfaction with the birth process. Two hundred sixty-four women (136 sweep and 128 no sweep) had their data analyzed. Ten women (4 sweep and 6 no sweep) were excluded because of exclusion criteria infringements. Swept women had higher spontaneous vaginal delivery rate (69% compared with 56%, P = .041), shorter induction to delivery interval (mean 14 compared with 19 hours, P = .003), fewer that required oxytocin use (46% compared with 59%, P = .037), shorter duration of oxytocin infusion (mean 2.6 compared with 4.3 hours, P = .001) and improved visual analog score for birth process satisfaction (mean 4.0 compared with 4.7, P = .015). The reduction in dinoprostone dose used (mean 1.2 compared with 1.3, P = .082) was not significant. Postsweeping visual analog score for pain (mean 4.7 compared with 3.5, P initiation of labor induction increased the spontaneous vaginal delivery rate, reduced oxytocic drug use, shortened induction to delivery interval, and improved patient satisfaction. I.

  6. Evaluation of two sweeping methods for estimating the number of immature Aedes aegypti (Diptera: Culicidae in large containers

    Directory of Open Access Journals (Sweden)

    Margareth Regina Dibo

    2013-07-01

    Full Text Available Introduction Here, we evaluated sweeping methods used to estimate the number of immature Aedes aegypti in large containers. Methods III/IV instars and pupae at a 9:1 ratio were placed in three types of containers with, each one with three different water levels. Two sweeping methods were tested: water-surface sweeping and five-sweep netting. The data were analyzed using linear regression. Results The five-sweep netting technique was more suitable for drums and water-tanks, while the water-surface sweeping method provided the best results for swimming pools. Conclusions Both sweeping methods are useful tools in epidemiological surveillance programs for the control of Aedes aegypti.

  7. Dealing with Cuts (For Parents)

    Science.gov (United States)

    ... For Kids For Parents MORE ON THIS TOPIC Cellulitis First Aid: Cuts Staph Infections Bites and Scratches First Aid: Falls First Aid: ... Out Cuts, Scratches, and Abrasions What's a Scab? Cellulitis Cuts, Scratches, and Scrapes Staph Infections Dealing With Cuts and Wounds Contact Us Print ...

  8. Theoretical Models for Orthogonal Cutting

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”......This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”...

  9. Theoretical Models for Orthogonal Cutting

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”......This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”...

  10. Using Computational Fluid Dynamics and Experiments to Design Sweeping Jets for High Reynolds Number Cruise Configurations

    Science.gov (United States)

    Jones, Gregory S.; Milholen, William E., II; Fell, Jared S.; Webb, Sandy R.; Cagle, C. Mark

    2016-01-01

    The application of a sweeping jet actuator to a circulation control system was initiated by a risk reduction series of experiments to optimize the authority of a single sweeping jet actuator. The sweeping jet design was integrated into the existing Fundamental Aerodynamic Subsonic Transonic- Modular Active Control (FAST-MAC) model by replacing the steady blowing system with an array of thirty-nine sweeping jet cartridges. A constant slot height to wing chord ratio was similar to the steady blowing configuration resulting in each actuator having a unique in size for the sweeping jet configuration. While this paper will describe the scaling and optimization of the actuators for future high Reynolds number applications, the major focus of this effort was to target the transonic flight regime by increasing the amplitude authority of the actuator. This was accomplished by modifying the diffuser of the sweeping jet actuator, and this paper highlights twelve different diffuser designs. The experimental portion of this work was completed in the NASA Langley National Transonic Facility.

  11. Frequency sweep rate dependence on the dielectrophoretic response of polystyrene beads and red blood cells

    Science.gov (United States)

    Adams, T. N. G.; Leonard, K. M.; Minerick, A. R.

    2013-01-01

    Alternating current (AC) dielectrophoresis (DEP) experiments for biological particles in microdevices are typically done at a fixed frequency. Reconstructing the DEP response curve from static frequency experiments is laborious, but essential to ascertain differences in dielectric properties of biological particles. Our lab explored the concept of sweeping the frequency as a function of time to rapidly determine the DEP response curve from fewer experiments. For the purpose of determining an ideal sweep rate, homogeneous 6.08 μm polystyrene (PS) beads were used as a model system. Translatability of the sweep rate approach to ∼7 μm red blood cells (RBC) was then verified. An Au/Ti quadrapole electrode microfluidic device was used to separately subject particles and cells to 10Vpp AC electric fields at frequencies ranging from 0.010 to 2.0 MHz over sweep rates from 0.00080 to 0.17 MHz/s. PS beads exhibited negative DEP assembly over the frequencies explored due to Maxwell-Wagner interfacial polarizations. Results demonstrate that frequency sweep rates must be slower than particle polarization timescales to achieve reliable incremental polarizations; sweep rates near 0.00080 MHz/s yielded DEP behaviors very consistent with static frequency DEP responses for both PS beads and RBCs. PMID:24396548

  12. Determination of the magnetocaloric entropy change by field sweep using a heat flux setup

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, J. C. B., E-mail: jolmiui@gmail.com; Reis, R. D. dos; Mansanares, A. M.; Gandra, F. G. [Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin, Campinas, SP 13083-859 (Brazil)

    2014-08-18

    We report on a simple setup using a heat flux sensor adapted to a Quantum Design Physical Property Measurement System to determine the magnetocaloric entropy change (ΔS). The major differences for the existing setups are the simplicity of this assembly and the ease to obtain the isothermal entropy change either by a field sweep or a temperature sweep process. We discuss the use of these two processes applied to Gd and Gd{sub 5}Ge{sub 2}Si{sub 2} samples. The results are compared to the temperature sweep measurements and they show the advantages of this setup and of the field sweep procedure. We found a significant reduction of ΔS and on the refrigerating cooling power (RCP) at low field changes in a field sweep process when the sample is not driven to the same initial state for each temperature. We show that the field sweep process without any measuring protocol is the only correct way to experimentally determine ΔS and RCP for a practical regenerative refrigerator.

  13. Increasing the detection rate of congenital heart disease during routine obstetric screening using cine loop sweeps.

    Science.gov (United States)

    Scott, Ted E; Jones, Judy; Rosenberg, Herschel; Thomson, Andrea; Ghandehari, Hournaz; Rosta, Neil; Jozkow, Kim; Stromer, Malka; Swan, Hans

    2013-06-01

    The purpose of this study was to demonstrate an increase in the detection rate of fetal cardiac defects using 2 cine loop sweeps. Image reviewers examined a series of 93 cases randomly sorted, including 79 studies with normal findings and 14 studies with abnormal findings. All of the images were assessed by 5 standard criteria. Cases were classified as normal, abnormal, or indeterminate. Reviewers using the conventional approach reviewed 3 still images: the 4-chamber, left ventricular outflow tract, and right ventricular outflow tract views. Reviewers using the cine loop sweeps viewed 2 grayscale sweeps through the fetal heart in real time. The image sequences were reviewed independently by 2 experts, 3 nonexperts, and 2 sonographers blinded to each others' results. The cine loop sweeps had an increased detection rate of 38% for the nonexperts and 36% for the experts compared with the conventional approach. The cine loop sweeps allowed identification of all cardiac defects by at least 2 of the 7 reviewers; the percentage of cases with false-positive findings was 3.9%. With the conventional approach, 2 defects went undetected by all reviewers, and 4 defects were found by only 1 reviewer; the percentage of cases with false-positive findings was 5.4%. The use of cine loop sweeps has the potential to increase the detection of fetal cardiac defects without increasing the rate of false-positive findings or increasing the interpretation and decision-making times.

  14. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou

    2000-01-30

    This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.

  15. The perfect cut

    DEFF Research Database (Denmark)

    Scozzafava, G.; Mueller Loose, Simone; Corsi, A.

    (organic, standard, GMO free). The cross-price elasticity provides insights to which degree different cuts compete against each other from a consumer perspective and how price premiums can be achieved by producers and marketers with certification and labeling strategies. The paper will also provide...... other from the consumer perspective dependent on price, intrinsic and extrinsic product characteristics as well as intended usage. So far, there is limited knowledge about optimal marketing and pricing of meat cuts simultaneously offered at the retail shelf. Results from an online choice experiment...

  16. "Kid Cuts" by Broderbund.

    Science.gov (United States)

    Martin, Ron

    1994-01-01

    Describes "Kid Cuts," an arts and crafts computer software program for students in prekindergarten through sixth grade that provides 22 activities in 6 curriculum areas. An example is given of an activity for kindergarten and first graders related to counting that includes library media skills objectives and mathematics objectives. (LRW)

  17. Cutting Cakes Carefully

    Science.gov (United States)

    Hill, Theodore P.; Morrison, Kent E.

    2010-01-01

    This paper surveys the fascinating mathematics of fair division, and provides a suite of examples using basic ideas from algebra, calculus, and probability which can be used to examine and test new and sometimes complex mathematical theories and claims involving fair division. Conversely, the classical cut-and-choose and moving-knife algorithms…

  18. Simultaneous Cake Cutting

    DEFF Research Database (Denmark)

    Balkanski, Eric; Branzei, Simina; Kurokawa, David;

    2014-01-01

    We introduce the simultaneous model for cake cutting (the fair allocation of a divisible good), in which agents simultaneously send messages containing a sketch of their preferences over the cake. We show that this model enables the computation of divisions that satisfy proportionality — a popular...

  19. Cutting Cakes Carefully

    Science.gov (United States)

    Hill, Theodore P.; Morrison, Kent E.

    2010-01-01

    This paper surveys the fascinating mathematics of fair division, and provides a suite of examples using basic ideas from algebra, calculus, and probability which can be used to examine and test new and sometimes complex mathematical theories and claims involving fair division. Conversely, the classical cut-and-choose and moving-knife algorithms…

  20. Kids Who Cut.

    Science.gov (United States)

    Coy, Doris Rhea; Simpson, Chris

    2002-01-01

    Regardless of whether it is cutting, burning or some other form of self-harm, self-injury is a serious problem requiring serious solutions. This article reviews the various types of self-harm, descriptions of self-mutilators, common myths about self-mutilation, and effective treatment methods. (GCP)

  1. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira

    2000-10-30

    This is the first quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between July 14, 2000 and September 30, 2000. This report presents information on the following specific tasks: (a) Progress in Advanced Cuttings Transport Facility design and development (Task 2), (b) Progress on research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress on research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress on research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress on research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Initiate research on project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Progress on instrumentation tasks to measure: Cuttings concentration and distribution (Tasks 11), and Foam properties (Task 12), (h) Initiate a comprehensive safety review of all flow-loop components and operational procedures. Since the previous Task 1 has been completed, we will now designate this new task as: (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  2. A selective sweep of >8 Mb on chromosome 26 in the Boxer genome

    Directory of Open Access Journals (Sweden)

    Altet Laura

    2011-07-01

    Full Text Available Abstract Background Modern dog breeds display traits that are either breed-specific or shared by a few breeds as a result of genetic bottlenecks during the breed creation process and artificial selection for breed standards. Selective sweeps in the genome result from strong selection and can be detected as a reduction or elimination of polymorphism in a given region of the genome. Results Extended regions of homozygosity, indicative of selective sweeps, were identified in a genome-wide scan dataset of 25 Boxers from the United Kingdom genotyped at ~20,000 single-nucleotide polymorphisms (SNPs. These regions were further examined in a second dataset of Boxers collected from a different geographical location and genotyped using higher density SNP arrays (~170,000 SNPs. A selective sweep previously associated with canine brachycephaly was detected on chromosome 1. A novel selective sweep of over 8 Mb was observed on chromosome 26 in Boxer and for a shorter region in English and French bulldogs. It was absent in 171 samples from eight other dog breeds and 7 Iberian wolf samples. A region of extended increased heterozygosity on chromosome 9 overlapped with a previously reported copy number variant (CNV which was polymorphic in multiple dog breeds. Conclusion A selective sweep of more than 8 Mb on chromosome 26 was identified in the Boxer genome. This sweep is likely caused by strong artificial selection for a trait of interest and could have inadvertently led to undesired health implications for this breed. Furthermore, we provide supporting evidence for two previously described regions: a selective sweep on chromosome 1 associated with canine brachycephaly and a CNV on chromosome 9 polymorphic in multiple dog breeds.

  3. Design and optimization of a bend-and-sweep compliant mechanism

    Science.gov (United States)

    Tummala, Y.; Frecker, M. I.; Wissa, A. A.; Hubbard, J. E., Jr.

    2013-09-01

    A novel contact aided compliant mechanism called bend-and-sweep compliant mechanism is presented in this paper. This mechanism has nonlinear stiffness properties in two orthogonal directions. An angled compliant joint (ACJ) is the fundamental element of this mechanism. Geometric parameters of ACJs determine the stiffness of the compliant mechanism. This paper presents the design and optimization of bend-and-sweep compliant mechanism. A multi-objective optimization problem was formulated for design optimization of the bend-and-sweep compliant mechanism. The objectives of the optimization problem were to maximize or minimize the bending and sweep displacements, depending on the situation, while minimizing the von Mises stress and mass of each mechanism. This optimization problem was solved using NSGA-II (a genetic algorithm). The results of this optimization for a single ACJ during upstroke and downstroke are presented in this paper. Results of two different loading conditions used during optimization of a single ACJ for upstroke are presented. Finally, optimization results comparing the performance of compliant mechanisms with one and two ACJs are also presented. It can be inferred from these results that the number of ACJs and the design of each ACJ determines the stiffness of the bend-and-sweep compliant mechanism. These mechanisms can be used in various applications. The goal of this research is to improve the performance of ornithopters by passively morphing their wings. In order to achieve a bio-inspired wing gait called continuous vortex gait, the wings of the ornithopter need to bend, and sweep simultaneously. This can be achieved by inserting the bend-and-sweep compliant mechanism into the leading edge wing spar of the ornithopters.

  4. Aspirin and clopidogrel: a sweeping combination in cardiology.

    Science.gov (United States)

    Manolis, Antonis S; Tzeis, Stylianos; Andrikopoulos, George; Koulouris, Spyros; Melita, Helen

    2005-07-01

    important large-scale clinical trials currently ongoing. Newer data are being accumulated from studies where indications for the use of clopidogrel and aspirin continue to expand into other patient groups, rendering this dual antiplatelet drug therapy a sweeping combination in Cardiology. However, important issues remain to be further and more thoroughly explored about the benefit of this antiplatelet drug combination in these other patient groups, such as in patients with heart failure, where preliminary data indicate a favorable effect on thrombotic vascular events, in patients with atrial fibrillation, where there is hope that this combination may replace or be an alternative treatment modality to coumadin in certain subpopulations, in patients undergoing demanding catheter ablation procedures, where data point to a protective effect from thromboembolic events. Another pertaining issue to be further investigated is the occurrence of drug-resistance observed in some patients for both these antithrombotic agents. This article is a comprehensive review of all these data and the landmark trials on the two antiplatelet agents, the issues involved and the current recommendations for their use in patients with atherosclerotic heart disease and other cardiovascular disorders and procedures.

  5. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-04-30

    Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have

  6. Investigation of the Hydrodynamics of Sweep Blade in Hi-Speed Axial Fuel Pump Impeller

    Directory of Open Access Journals (Sweden)

    Ran Tao

    2013-01-01

    Full Text Available Fuel pump is a crucial component in aircraft engine ignition system. For the hi-speed axial fuel pumps, rotating stall triggers vortex and affects the operation stability and security. Sweep blade is widely used to solve the stability problems in aerodynamics field. Investigation on the hydrodynamics was conducted in this study. Based on the typical straight blade pump, positive and negative sweep blade pumps were modeled. With the large eddy simulation method, CFD simulations were conducted to calculate and analyze the flow characteristics in the pump models. To verify the simulation, experiments were also launched on the hydraulic test rig. Results show that the vortex occurs at the suction surface of blade and gathers near the blade tip region. Positive sweep blade is effective to reduce the hydraulic losses by driving the stalled fluid into the mid-part of blade. By applying the positive sweep blade on the axial fuel pump, the instability operating region will be diminished. Adopting sweep blade provides an effective means for stability and security of axial fuel pumps.

  7. Numerical Investigation of Blade Lean and Sweep affecting Secondary Flows in an Axial Expansion Turbine

    Science.gov (United States)

    Neipp, A.; Riedelbauch, S.

    2016-11-01

    Based on an axial expansion turbine used for energy recovery from working fluids an automated CFD-flow optimization was performed to increase the turbine efficiency without narrowing the operating range. The optimization results showed that even small changes in the optimization target had a significant influence on the lean and sweep of the new blade designs. The resulting blade shapes were extraordinary. The lean and sweep resembled more that of thermal turbomachinery than hydraulic machinery. It became clear that the special blade shapes were a result of the very low aspect ratio of the turbine and the resulting large influence of secondary flows. The blade lean and sweep induce secondary flow structures which are of decisive importance for the turbine performance. The simulation results showed that positive compound lean increases the efficiency and positive compound sweep improves the cavitation behavior of the investigated axial expansion turbine. However the complexity of the occurring secondary flows make an universally valid statement on the effect of blade lean and sweep on the flow behavior of an axial turbine impossible.

  8. Acupuncture and/or sweeping of the fetal membranes before induction of labor

    DEFF Research Database (Denmark)

    Andersen, Bodil Birgitte; Knudsen, Birthe; Lyndrup, Jens

    2013-01-01

    AIMS: To evaluate the efficacy of acupuncture, and sweeping of the fetal membranes, as methods for induction of labor. METHODS: Four hundred and seven pregnant women with normal singleton pregnancies and cephalic presentations were randomized at three delivery wards in Denmark at day 290 of gesta......AIMS: To evaluate the efficacy of acupuncture, and sweeping of the fetal membranes, as methods for induction of labor. METHODS: Four hundred and seven pregnant women with normal singleton pregnancies and cephalic presentations were randomized at three delivery wards in Denmark at day 290...... of gestation into groups of acupuncture, sweeping, acupuncture and sweeping and controls. The primary objective was to compare the proportion of women going into labor before induction of labor at 294 days in the four groups. The secondary objective was to compare the combined groups: with and without...... acupuncture, and with and without sweeping of the fetal membranes. The midwives, completing the forms for the trial at labor or induction, were blinded to group assessments. RESULTS: Four hundred and seventeen women were randomized. Ten were excluded after randomization. One hundred and four women were...

  9. All-fiber broad-range self-sweeping Yb-doped fiber laser

    Science.gov (United States)

    Lobach, Ivan A.; Kablukov, Sergey A.; Podivilov, Evgeniy V.; Babin, Sergey A.

    2012-02-01

    The effect of broad-range self-sweeping in Yb-doped fiber laser has been demonstrated experimentally for the first time. The self-sweeping effect is observed in an all-fiber laser configuration with a double-clad Yb-doped fiber and a cavity formed by a broad-band fiber loop mirror and Fresnel reflection from one cleaved end. The sweep range is limited by the width of the broad-band reflector and reaches up to 16nm. It is found that the self-sweeping effect is related to selfpulsations. So the sweep rate is increased with an increase in pump power and is decreased with increasing cavity length. RF and optical spectra (linewidth is measured to be not more than 100 MHz) show that during the evolution of a single pulse a small number of longitudinal modes take a part in lasing. Based on these results we propose a model describing dynamics of the laser frequency. The model is based on the spatial hole burning effect and the gain saturation in Yb laser transition, and takes into account self-pulsations of the laser. Theoretical estimation for pulse to pulse change of lasing frequency is in good agreement with experimental data.

  10. NUMERICAL BOUNDARY CONDITIONS FOR THE FAST SWEEPING HIGH ORDER WENO METHODS FOR SOLVING THE EIKONAL EQUATION

    Institute of Scientific and Technical Information of China (English)

    Ling Huang; Chi-Wang Shu; Mengping Zhang

    2008-01-01

    High order fast sweeping methods have been developed recently in the literature to solve static Hamilton-Jacobi equations efficiently. Comparing with the first order fast sweeping methods, the high order fast sweeping methods are more accurate, but they often require additional numerical boundary treatment for several grid points near the boundary because of the wider numerical stencil. It is particularly important to treat the points near the inflow boundary accurately, as the information would flow into the computational domain and would affect global accuracy. In the literature, the numerical solution at these boundary points are either fixed with the exact solution, which is not always feasible, or computed with a first order discretization, which could reduce the global accuracy. In this paper, we discuss two strategies to handle the inflow boundary conditions. One is based on the numerical solutions of a first order fast sweeping method with several different mesh sizes near the boundary and a Richardson extrapolation, the other is based on a Lax-Wendroff type procedure to repeatedly utilizing the PDE to write the normal spatial derivatives to the inflow boundary in terms of the tangential derivatives, thereby obtaining high order solution values at the grid points near the inflow boundary. We explore these two approaches using the fast sweeping high order WENO scheme in [18] for solving the static Eikonal equation as a representative example. Numerical examples are given to demonstrate the performance of these two approaches.

  11. Cutting forces during turning with variable depth of cut

    Directory of Open Access Journals (Sweden)

    M. Sadílek

    2016-03-01

    The proposed research for the paper is an experimental work – measuring cutting forces and monitoring of the tool wear on the cutting edge. It compares the turning where standard roughing cycle is used and the turning where the proposed roughing cycle with variable depth of cut is applied.

  12. Cutting Out Continuations

    DEFF Research Database (Denmark)

    Bahr, Patrick; Hutton, Graham

    2016-01-01

    In the field of program transformation, one often transforms programs into continuation-passing style to make their flow of control explicit, and then immediately removes the resulting continuations using defunctionalisation to make the programs first-order. In this article, we show how these two...... transformations can be fused together into a single transformation step that cuts out the need to first introduce and then eliminate continuations. Our approach is calculational, uses standard equational reasoning techniques, and is widely applicable....

  13. Manual bamboo cutting tool.

    Science.gov (United States)

    Bezerra, Mariana Pereira; Correia, Walter Franklin Marques; da Costa Campos, Fabio Ferreira

    2012-01-01

    The paper presents the development of a cutting tool guide, specifically for the harvest of bamboo. The development was made based on precepts of eco-design and ergonomics, for prioritizing the physical health of the operator and the maintenance of the environment, as well as meet specific requirements of bamboo. The main goal is to spread the use of bamboo as construction material, handicrafts, among others, from a handy, easy assembly and material available tool.

  14. Making the cut

    OpenAIRE

    Millard, Chris

    2013-01-01

    ‘Deliberate self-harm’, ‘self-mutilation’ and ‘self-injury’ are just some of the terms used to describe one of the most prominent issues in British mental health policy in recent years. This article demonstrates that contemporary literature on ‘self-harm’ produces this phenomenon (to varying extents) around two key characteristics. First, this behaviour is predominantly performed by those identified as female. Second, this behaviour primarily involves cutting the skin. These constitutive char...

  15. Soluble oil cutting fluid

    Energy Technology Data Exchange (ETDEWEB)

    Rawlinson, A.P.; White, J.

    1987-06-23

    A soluble oil, suitable when diluted with water, for use as a cutting fluid comprises an alkali or alkaline-earth metal alkyl benzene sulphonate, a fatty acid diethanolamide, a mixed alkanolamine borate, a polyisobutenesuccinimide and a major proportion of mineral oil. The soluble oil is relatively stable without the need for a conventional coupling agent and some soluble oil emulsions are bio-static even though conventional biocides are not included.

  16. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Neelima Godugu

    2000-07-30

    ACTS flow loop is now operational under elevated pressure and temperature. Currently, experiments with synthetic based drilling fluids under pressure and temperature are being conducted. Based on the analysis of Fann 70 data, empirical correlations defining the shear stress as a function of temperature, pressure and the shear rate have been developed for Petrobras synthetic drilling fluids. PVT equipment has been modified for testing Synthetic oil base drilling fluids. PVT tests with Petrobras Synthetic base mud have been conducted and results are being analyzed Foam flow experiments have been conducted and the analysis of the data has been carried out to characterize the rheology of the foam. Comparison of pressure loss prediction from the available foam hydraulic models and the test results has been made. Cuttings transport experiments in horizontal annulus section have been conducted using air, water and cuttings. Currently, cuttings transport tests in inclined test section are being conducted. Foam PVT analysis tests have been conducted. Foam stability experiments have also been conducted. Effects of salt and oil concentration on the foam stability have been investigated. Design of ACTS flow loop modification for foam and aerated mud flow has been completed. A flow loop operation procedure for conducting foam flow experiments under EPET conditions has been prepared Design of the lab-scale flow loop for dynamic foam characterization and cuttings monitoring instrumentation tests has been completed. The construction of the test loop is underway. As part of the technology transport efforts, Advisory Board Meeting with ACTS-JIP industry members has been organized on May 13, 2000.

  17. EFFECT OF SWEEP ANGLE ON THE VORTICAL FLOW OVER DELTA WINGS AT AN ANGLE OF ATTACK OF 10°

    Directory of Open Access Journals (Sweden)

    JAMES BRETT

    2014-12-01

    Full Text Available CFD simulations have been used to analyse the vortical flows over sharp edged delta wings with differing sweep angles under subsonic conditions at an angle of attack of 10°. RANS simulations were validated against experimental data for a 65° sweep wing, with a flat cross-section, and the steadiness of the flow field was assessed by comparing the results against unsteady URANS and DES simulations. To assess the effect of sweep angle on the flow field, a range of sweep angles from 65° to 43° were simulated. For moderate sweep wings the primary vortex was observed to detach from the leading edge, undergoing vortex breakdown, and a weaker, replacement, "shadow" vortex was formed. The shadow vortex was observed for sweep angles of 50° and less, and resulted in reduced lift production near the wing tips loss of the stronger primary vortex.

  18. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Len Volk; Mark Pickell; Evren Ozbayoglu; Barkim Demirdal; Paco Vieira; Affonso Lourenco

    1999-10-15

    This report includes a review of the progress made in ACTF Flow Loop development and research during 90 days pre-award period (May 15-July 14, 1999) and the following three months after the project approval date (July15-October 15, 1999) The report presents information on the following specific subjects; (a) Progress in Advanced Cuttings Transport Facility design and development, (b) Progress report on the research project ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress report on the research project ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress report on the research project ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress report on the research project ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Progress report on the instrumentation tasks (Tasks 11 and 12) (g) Activities towards technology transfer and developing contacts with oil and service company members.

  19. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-07-30

    This Quarter has been divided between running experiments and the installation of the drill-pipe rotation system. In addition, valves and piping were relocated, and three viewports were installed. Detailed design work is proceeding on a system to elevate the drill-string section. Design of the first prototype version of a Foam Generator has been finalized, and fabrication is underway. This will be used to determine the relationship between surface roughness and ''slip'' of foams at solid boundaries. Additional cups and rotors are being machined with different surface roughness. Some experiments on cuttings transport with aerated fluids have been conducted at EPET. Theoretical modeling of cuttings transport with aerated fluids is proceeding. The development of theoretical models to predict frictional pressure losses of flowing foam is in progress. The new board design for instrumentation to measure cuttings concentration is now functioning with an acceptable noise level. The ultrasonic sensors are stable up to 190 F. Static tests with sand in an annulus indicate that the system is able to distinguish between different sand concentrations. Viscometer tests with foam, generated by the Dynamic Test Facility (DTF), are continuing.

  20. Performance Testing of Cutting Fluids

    DEFF Research Database (Denmark)

    Belluco, Walter

    within the whole range of operations, materials, cutting fluids, operating conditions, etc. Cutting fluid performance was evaluated in turning, drilling, reaming and tapping, and with respect to tool life, cutting forces, chip formation and product quality (dimensional accuracy and surface integrity......). A number of different work materials were considered, with emphasis on austenitic stainless steel. Cutting fluids from two main groups were investigated, water miscible (reviewed from previous work) and straight oils. Results show that correlation of cutting fluid performance in different operations exists...... within the same group of cutting fluids, for stainless steel. A possible rationalisation of cutting fluid performance tests is suggested. In order to select a set of basic tests and optimise them for use as general and standardised testing methods, an original approach to the evaluation of cutting force...

  1. Performance Testing of Cutting Fluids

    DEFF Research Database (Denmark)

    Belluco, Walter

    The importance of cutting fluid performance testing has increased with documentation requirements of new cutting fluid formulations based on more sustainable products, as well as cutting with minimum quantity of lubrication and dry cutting. Two sub-problems have to be solved: i) which machining...... tests feature repeatability, reproducibility and sensitivity to cutting fluids, and ii) to what extent results of one test ensure relevance to a wider set of machining situations. The present work is aimed at assessing the range of validity of the different testing methods, investigating correlation...... within the whole range of operations, materials, cutting fluids, operating conditions, etc. Cutting fluid performance was evaluated in turning, drilling, reaming and tapping, and with respect to tool life, cutting forces, chip formation and product quality (dimensional accuracy and surface integrity...

  2. Hybrid massively parallel fast sweeping method for static Hamilton–Jacobi equations

    Energy Technology Data Exchange (ETDEWEB)

    Detrixhe, Miles, E-mail: mdetrixhe@engineering.ucsb.edu [Department of Mechanical Engineering (United States); University of California Santa Barbara, Santa Barbara, CA, 93106 (United States); Gibou, Frédéric, E-mail: fgibou@engineering.ucsb.edu [Department of Mechanical Engineering (United States); University of California Santa Barbara, Santa Barbara, CA, 93106 (United States); Department of Computer Science (United States); Department of Mathematics (United States)

    2016-10-01

    The fast sweeping method is a popular algorithm for solving a variety of static Hamilton–Jacobi equations. Fast sweeping algorithms for parallel computing have been developed, but are severely limited. In this work, we present a multilevel, hybrid parallel algorithm that combines the desirable traits of two distinct parallel methods. The fine and coarse grained components of the algorithm take advantage of heterogeneous computer architecture common in high performance computing facilities. We present the algorithm and demonstrate its effectiveness on a set of example problems including optimal control, dynamic games, and seismic wave propagation. We give results for convergence, parallel scaling, and show state-of-the-art speedup values for the fast sweeping method.

  3. Absolute distance measurement using frequency-sweeping heterodyne interferometer calibrated by an optical frequency comb.

    Science.gov (United States)

    Wu, Xuejian; Wei, Haoyun; Zhang, Hongyuan; Ren, Libing; Li, Yan; Zhang, Jitao

    2013-04-01

    We present a frequency-sweeping heterodyne interferometer to measure an absolute distance based on a frequency-tunable diode laser calibrated by an optical frequency comb (OFC) and an interferometric phase measurement system. The laser frequency-sweeping process is calibrated by the OFC within a range of 200 GHz and an accuracy of 1.3 kHz, which brings about a precise temporal synthetic wavelength of 1.499 mm. The interferometric phase measurement system consisting of the analog signal processing circuit and the digital phase meter achieves a phase difference resolution better than 0.1 deg. As the laser frequency is sweeping, the absolute distance can be determined by measuring the phase difference variation of the interference signals. In the laboratory condition, our experimental scheme realizes micrometer accuracy over meter distance.

  4. Hybrid massively parallel fast sweeping method for static Hamilton-Jacobi equations

    Science.gov (United States)

    Detrixhe, Miles; Gibou, Frédéric

    2016-10-01

    The fast sweeping method is a popular algorithm for solving a variety of static Hamilton-Jacobi equations. Fast sweeping algorithms for parallel computing have been developed, but are severely limited. In this work, we present a multilevel, hybrid parallel algorithm that combines the desirable traits of two distinct parallel methods. The fine and coarse grained components of the algorithm take advantage of heterogeneous computer architecture common in high performance computing facilities. We present the algorithm and demonstrate its effectiveness on a set of example problems including optimal control, dynamic games, and seismic wave propagation. We give results for convergence, parallel scaling, and show state-of-the-art speedup values for the fast sweeping method.

  5. A simple frequency sweep linearization method for FM density profile reflectometry

    Science.gov (United States)

    Liu, Adi; Hu, Jianqiang; Doyle, Edward; Zhang, Jin; Li, Hong; Zhou, Chu; Zhang, Xiaohui; Wang, Mingyuan; Lan, Tao; Xie, Jinglin; Liu, Wandong; Yu, Changxuan

    2015-11-01

    Frequency modulated, continuous wave (FMCW) reflectometry is widely used to measure the electron density profile on fusion devices. To ensure the output intermediate frequency signal is proportional to the propagation delay time, the frequency sweep should be linearized, especially for reflectometry with sweeping periods of only a few microseconds. We introduce a simple dynamic calibration technique to linearize the frequency sweep based on digital complex demodulation methods, without using a Fourier transform, which would induce a trade-off between frequency and time resolution. The technique is convenient as it can be done in the same conditions as for plasma measurements. The method is in use on the EAST profile reflectometer, and results will be presented. Work was supported by the Natural Science Foundation of China (NSFC) under 11475173, National Magnetic Confinement Fusion Energy Development Program of China under 2013GB106002 and 2014GB109002, and US DOE Grants DE- SC0010424 and DE-SC0010469.

  6. Cleaning mechanism of particle contaminants on large aperture optical components by using air knife sweeping technology

    Science.gov (United States)

    Niu, Longfei; Liu, Hao; Miao, Xinxiang; Lv, Haibing; Yuan, Xiaodong; Zhou, Hai; Yao, Caizhen; Zhou, Guorui; Li, Qin

    2017-05-01

    The cleaning mechanism of optical surface particle contaminants in the light pneumatic tube was simulated based on the static equations and JKR model. Cleaning verification experiment based on air knife sweeping system and on-line monitoring system in high power laser facility was set up in order to verify the simulated results. Results showed that the removal ratio is significantly influenced by sweeping velocity and angle. The removal ratio can reach to 94.3% by using higher input pressure of the air knife, demonstrating that the air knife sweeping technology is useful for maintaining the surface cleanliness of optical elements, and thus guaranteeing the long-term stable running of the high power laser facility.

  7. Efficient Path Finding with the Sweep-Line Method using External Storage

    DEFF Research Database (Denmark)

    Kristensen, Lars Michael; Mailund, Thomas

    2003-01-01

    space exploration and gives the same reduction in peak memory usage as the stand-alone sweep-line method. We evaluate the proposed technique on a number of example systems, and compare its performance to a related technique. These practical experiments demonstrate how the suggested technique complements......The sweep-line method deletes states on-the-fly during state space exploration to reduce peak memory usage. This deletion of states prohibits the immediate generation of, e.g., an error-trace when the violation of a safety property is detected. We address this problem by combining the sweep......-line method with storing a spanning tree of the explored state space in external storage on a magnetic disk. We show how this allows us to easily obtain paths in the state space, such as error-traces. A key property of the proposed technique is that it avoids searching in external storage during the state...

  8. Application of Sweeping Jet Actuators on the NASA Hump Model and Comparison with CFDVAL2004 Experiments

    Science.gov (United States)

    Koklu, Mehti

    2017-01-01

    Flow separation control over a wall-mounted hump model was studied experimentally to assess the performance of sweeping jet actuators. Results were compared to that of the 2004 CFD validation experiment (CFDVAL2004), which examined flow separation control with steady suction and unsteady zero-net-mass-flow actuators. Comparisons were carried out at low and high amplitude excitations. In addition to the active flow control methods, a passive flow control method (i.e., vortex generator) was used to complement the dataset. Steady/unsteady surface pressure measurements and surface oilflow visualization were used in the performance assessment of the actuators. The results indicated that the sweeping jet actuators are more effective than the steady suction and unsteady zero-net-mass-flow actuators. For the same momentum coefficient, the sweeping jet actuators produced more flow acceleration upstream of separation, more pressure recovery downstream, and consistently a smaller separation bubble.

  9. Application of the WEPS and SWEEP models to non-agricultural disturbed lands

    Directory of Open Access Journals (Sweden)

    J. Tatarko

    2016-12-01

    Full Text Available Wind erosion not only affects agricultural productivity but also soil, air, and water quality. Dust and specifically particulate matter ≤10 μm (PM-10 has adverse effects on respiratory health and also reduces visibility along roadways, resulting in auto accidents. The Wind Erosion Prediction System (WEPS was developed by the USDA-Agricultural Research Service to simulate wind erosion and provide for conservation planning on cultivated agricultural lands. A companion product, known as the Single-Event Wind Erosion Evaluation Program (SWEEP, has also been developed which consists of the stand-alone WEPS erosion submodel combined with a graphical interface to simulate soil loss from single (i.e., daily wind storm events. In addition to agricultural lands, wind driven dust emissions also occur from other anthropogenic sources such as construction sites, mined and reclaimed areas, landfills, and other disturbed lands. Although developed for agricultural fields, WEPS and SWEEP are useful tools for simulating erosion by wind for non-agricultural lands where typical agricultural practices are not employed. On disturbed lands, WEPS can be applied for simulating long-term (i.e., multi-year erosion control strategies. SWEEP on the other hand was developed specifically for disturbed lands and can simulate potential soil loss for site- and date-specific planned surface conditions and control practices. This paper presents novel applications of WEPS and SWEEP for developing erosion control strategies on non-agricultural disturbed lands. Erosion control planning with WEPS and SWEEP using water and other dust suppressants, wind barriers, straw mulch, re-vegetation, and other management practices is demonstrated herein through the use of comparative simulation scenarios. The scenarios confirm the efficacy of the WEPS and SWEEP models as valuable tools for supporting the design of erosion control plans for disturbed lands that are not only cost-effective but

  10. Active Flow Control Using Sweeping Jet Actuators on a Semi-Span Wing Model

    Science.gov (United States)

    Melton, LaTunia Pack; Koklu, Mehti

    2016-01-01

    Wind tunnel experiments were performed using active flow control on an unswept semispan wing model with a 30% chord trailing edge flap to aid in the selection of actuators for a planned high Reynolds number experiment. Two sweeping jet actuator sizes were investigated to determine the influence of actuator size on the active flow control system efficiency. Sweeping jet actuators with orifice sizes of 1 mm x 2 mm and 2 mm x 4 mm were selected because of the differences in actuator jet sweep angle. The parameters that were varied include actuator momentum, freestream velocity, and trailing edge flap deflection angle. Steady and unsteady pressure data, Particle Image Velocimetry data, and force and moment data were acquired to assess the performance of the two actuators. In addition to the wind tunnel experiments, benchtop studies of the actuators were performed to characterize the jets produced by each actuator. Benchtop investigations of the smaller actuator reveal that the jet exiting the actuator has a reduced sweep angle compared to published data for larger versions of this type of actuator. The larger actuator produces an oscillating jet that attaches to the external di?user walls at low supply pressures and produces the expected sweep angles. The AFC results using the smaller actuators show that while the actuators can control flow separation, the selected spacing of 3.3 cm may be too large due to the reduced sweep angle. In comparison, the spacing for the larger actuators, 6.6 cm, appears to be optimal for the Mach numbers investigated. Particle Image Velocimetry results are presented and show how the wall jets produced by the actuators cause the flow to attach to the flap surface.

  11. Self-Propelled Sweeping Removal of Dropwise Condensate on Two-Tier Superhydrophobic Surfaces

    Science.gov (United States)

    Boreyko, Jonathan; Qu, Xiaopeng; Liu, Fangjie; Agapov, Rebecca; Lavrik, Nickolay; Retterer, Scott; Feng, James; Collier, Patrick; Chen, Chuan-Hua; Nature-Inspired Fluids; Interfaces Team; Microscale Physicochemical Hydrodynamics Laboratory Team; CenterNanophase Materials Sciences Team; Department of Mathematics Team

    2015-11-01

    Dropwise condensation can be enhanced by nanostructured superhydrophobic surfaces, on which the condensate drops spontaneously jump upon coalescence. However, the self-propelled jumping in prior reports is mostly perpendicular to the substrate. Here, we propose a substrate design with regularly spaced micropillars. Coalescence on the sidewalls of the micropillars leads to self-propelled jumping in a direction nearly orthogonal to the pillars and therefore parallel to the substrate. This in-plane motion in turn produces sweeping removal of multiple neighboring drops. The spontaneous sweeping mechanism may greatly enhance dropwise condensation in a self-sustained manner.

  12. New linear sweep technique to measure generation lifetimes in thin-film SOI MOSFET's

    Science.gov (United States)

    Venkatesan, S.; Pierret, R. F.; Neudeck, G. W.

    1994-04-01

    A new linear sweep technique to measure generation lifetimes (tau(sub g)) in silicon-on-insulator (SOI) material is presented. A detailed analytic formulation is applied to fully-depleted and partially-depleted SOI films and used to simulate the behavior of the SOI devices under linear sweep conditions. A novel algorithm accurately determines the effective generation width in fully depleted SOI films. The measurement technique is experimentally verified by applying the algorithm to fully depleted SIMOX P-channel MOSFET's where observed lifetimes ranged from 0.3 mu s to 2.4 mu s.

  13. Reinterpretation of reduction potential measurements done by linear sweep voltammetry in silicate melts

    Science.gov (United States)

    Colson, R. O.; Haskin, L. A.; Keedy, C. R.

    1991-01-01

    The equilibrium concentrations of Ni between silicate melt and Pt were determined experimentally as a function of oxygen fugacity. The results demonstrate that metallic species derived in linear sweep voltammetry experiments in silicate melts are diffusing into Pt electrodes and not into the melt, as was concluded by previoius studies. This requires reinterpretation of previous linear sweep voltammetry results and recalculation and correction of reported reduction potentials. This paper reports these corrected reduction potentials. Also reported are the activity coefficients for Ni in synthetic basalt and diopsidic melts and for Co in diopsidic melt.

  14. On detecting incomplete soft or hard selective sweeps using haplotype structure

    DEFF Research Database (Denmark)

    Ferrer-Admetlla, Anna; Liang, Mason; Korneliussen, Thorfinn Sand

    2014-01-01

    We present a new haplotype-based statistic (nSL) for detecting both soft and hard sweeps in population genomic data from a single population. We compare our new method with classic single-population haplotype and site frequency spectrum (SFS)-based methods and show that it is more robust, particu......We present a new haplotype-based statistic (nSL) for detecting both soft and hard sweeps in population genomic data from a single population. We compare our new method with classic single-population haplotype and site frequency spectrum (SFS)-based methods and show that it is more robust...

  15. A convergence analysis for a sweeping preconditioner for block tridiagonal systems of linear equations

    KAUST Repository

    Bagci, Hakan

    2014-11-11

    We study sweeping preconditioners for symmetric and positive definite block tridiagonal systems of linear equations. The algorithm provides an approximate inverse that can be used directly or in a preconditioned iterative scheme. These algorithms are based on replacing the Schur complements appearing in a block Gaussian elimination direct solve by hierarchical matrix approximations with reduced off-diagonal ranks. This involves developing low rank hierarchical approximations to inverses. We first provide a convergence analysis for the algorithm for reduced rank hierarchical inverse approximation. These results are then used to prove convergence and preconditioning estimates for the resulting sweeping preconditioner.

  16. Cutting the Cord-2

    Science.gov (United States)

    2004-01-01

    This animation shows the view from the rear hazard avoidance cameras on the Mars Exploration Rover Spirit as the rover turns 45 degrees clockwise. This maneuver is the first step in a 3-point turn that will rotate the rover 115 degrees to face west. The rover must make this turn before rolling off the lander because airbags are blocking it from exiting from the front lander petal. Before this crucial turn took place, engineers instructed the rover to cut the final cord linking it to the lander. The turn took around 30 minutes to complete.

  17. Cutting the Cord

    Science.gov (United States)

    2004-01-01

    This animation shows the view from the front hazard avoidance cameras on the Mars Exploration Rover Spirit as the rover turns 45 degrees clockwise. This maneuver is the first step in a 3-point turn that will rotate the rover 115 degrees to face west. The rover must make this turn before rolling off the lander because airbags are blocking it from exiting off the front lander petal. Before this crucial turn could take place, engineers instructed the rover to cut the final cord linking it to the lander. The turn took around 30 minutes to complete.

  18. Drilling cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Capuano, L.E. Jr.

    1996-12-31

    This presentation by Louis E. Capuano, Jr., President, ThermaSource, Inc., discusses cost-cutting in the drilling phase of geothermal energy exploration and production. All aspects of a geothermal project including the drilling must be streamlined to make it viable and commercial. If production could be maximized from each well, there would be a reduction in drilling costs. This could be achieved in several ways, including big hole and multi-hole completion, directional drilling, better knowledge of the resource and where to penetrate, etc.

  19. Improved performance of linear coal cutting compared with rotary cutting

    Energy Technology Data Exchange (ETDEWEB)

    Roepke, W.W.; Hanson, B.D.; Olson, R.C.; Wingquist, C.F.; Myren, T.A.

    1995-09-01

    The linear cutting system, developed by the US Bureau of Mines uses geometric principles developed by Cardan to produce a nearly constant cut depth. The new system has been extensively tested in a synthetic material under laboratory conditions to verify mechanical capability and to identify operational characteristics. Comparison between 15-rpm linear cutting and 50-rpm rotary cutting systems show significant improvement in respirable dust entrainment, product size distribution, and energy usage. Respirable dust is reduced by as much as 90%. Recovered product showed a 67% reduction in {minus}0.32-cm ({minus}1/8-in) material and a 200% increase in +5.08 cm (+ 2 in) materials. Average power was reduced by 66% for the linear cutting. Because the bit cutting paths differ between linear and rotary cutting, it was necessary to compare the two at the same cut depths and bit types. These comparisons show that low revolution per minute rotary cutting entrains about the same amount of respirable dust as the linear cutting system, but the average shaft torque may be 55 to 130% greater for the rotary system.

  20. CO2 laser cutting

    CERN Document Server

    Powell, John

    1998-01-01

    The laser has given manufacturing industry a new tool. When the laser beam is focused it can generate one of the world's most intense energy sources, more intense than flames and arcs, though similar to an electron beam. In fact the intensity is such that it can vaporise most known materials. The laser material processing industry has been growing swiftly as the quality, speed and new manufacturing possibilities become better understood. In the fore of these new technologies is the process of laser cutting. Laser cutting leads because it is a direct process substitu­ tion and the laser can usually do the job with greater flexibility, speed and quality than its competitors. However, to achieve these high speeds with high quality con­ siderable know how and experience is required. This information is usually carefully guarded by the businesses concerned and has to be gained by hard experience and technical understanding. Yet in this book John Powell explains in lucid and almost non­ technical language many o...

  1. Efficacy and safety of serial membrane sweeping to prevent post term pregnancy: a randomised study

    Directory of Open Access Journals (Sweden)

    Sabita Saichandran

    2015-12-01

    Conclusions: Serial membrane sweeping is both safe and effective in the prevention of pregnancy beyond 41 weeks. Hence reduces the post term pregnancy, need for induction of labour and related risks in low pregnancies. [Int J Reprod Contracept Obstet Gynecol 2015; 4(6.000: 1882-1886

  2. Sweeping of alprenolol enantiomers with an organic solvent and sulfated β-cyclodextrin in capillary electrophoresis.

    Science.gov (United States)

    Rabanes, Heide R; Quirino, Joselito P

    2013-05-01

    Sweeping, an on-line sample concentration technique in CE, is the picking and accumulation of analytes by the pseudostationary phase or complexing additive. In the presence of an electric field, the analytes concentrated at the additive front that initially penetrated the sample zone. Here, we describe the sweeping of cationic alprenolol enantiomers using sulfated β-CD and organic solvent. The separation solution contained the anionic additive while ACN was in the sample solution. With fused silica capillaries, positive polarity, and solutions buffered at pH 3, the direction of the enantiomers' effective electrophoretic mobility was the same as the electrophoretic mobility (or electrophoretic mobility without additive). When the amount of ACN in the sample was increased (i.e. 60%), the interaction between the analytes and additive became negligible. This caused the sweeping boundary to shift from the electrophoretically moving β-CD front to the zone between the sample and separation solution. The equation that described the narrowing of injected sample zone was derived. The performance of sweeping with 60% ACN in the sample was then studied under different operating conditions (e.g. type of injection, injection time, and CD concentration). The low interaction between enantiomers and additive gave only moderate increases in sensitivity (approximately tenfold), but was improved when field enhancement was used during electrokinetic injection. With a conductivity difference (separation/sample solution) of 70 and a short injection time of 30 s at 20 kV, peak improvements of >100-fold was easily achieved.

  3. Lock-free parallel and concurrent garbage collection by mark&sweep

    NARCIS (Netherlands)

    Gao, H.; Groote, J. F.; Hesselink, W. H.

    2007-01-01

    This paper presents a lock-free algorithm for mark&sweep garbage collection (GC) in a realistic model using synchronization primitives load-linked/store-conditional (LL/SC) or compare-and-swap (CAS) offered by machine arch i lectures. The algorithm is concurrent in the sense that garbage collection

  4. Masking of short probe sounds by tone bursts with a sweeping frequency

    NARCIS (Netherlands)

    Smoorenburg, G.F.; Coninx, F.

    1980-01-01

    The maske threshold of short (≤ 40 ms) probe tone or a short one-third octave probe noise appears to increase if the frequency of a tonal masker is swept. Frequency sweeps were exponential (octaves/s) and unidirectional. Probe sounds were presented in the time center of the masker at the center freq

  5. Wingbeat frequency-sweep and visual stimuli for trapping male Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Combinations of female wingbeat acoustic cues and visual cues were evaluated to determine their potential for use in male Aedes aegypti (L.) traps in peridomestic environments. A modified Centers for Disease control (CDC) light trap using a 350-500 Hz frequency-sweep broadcast from a speaker as an a...

  6. Effect of blade sweep on inlet flow in axial compressor cascades

    Directory of Open Access Journals (Sweden)

    Hao Chang

    2015-02-01

    Full Text Available This paper presents comparative numerical studies to investigate the effects of blade sweep on inlet flow in axial compressor cascades. A series of swept and straight cascades was modeled in order to obtain a general understanding of the inlet flow field that is induced by sweep. A computational fluid dynamics (CFD package was used to simulate the cascades and obtain the required three-dimensional (3D flow parameters. A circumferentially averaged method was introduced which provided the circumferential fluctuation (CF terms in the momentum equation. A program for data reduction was conducted to obtain a circumferentially averaged flow field. The influences of the inlet flow fields of the cascades were studied and spanwise distributions of each term in the momentum equation were analyzed. The results indicate that blade sweep does affect inlet radial equilibrium. The characteristic of radial fluid transfer is changed and thus influencing the axial velocity distributions. The inlet flow field varies mainly due to the combined effect of the radial pressure gradient and the CF component. The axial velocity varies consistently with the incidence variation induced by the sweep, as observed in the previous literature. In addition, factors that might influence the radial equilibrium such as blade camber angles, solidity and the effect of the distance from the leading edge are also taken into consideration and comparatively analyzed.

  7. S/HIC: Robust Identification of Soft and Hard Sweeps Using Machine Learning.

    Directory of Open Access Journals (Sweden)

    Daniel R Schrider

    2016-03-01

    Full Text Available Detecting the targets of adaptive natural selection from whole genome sequencing data is a central problem for population genetics. However, to date most methods have shown sub-optimal performance under realistic demographic scenarios. Moreover, over the past decade there has been a renewed interest in determining the importance of selection from standing variation in adaptation of natural populations, yet very few methods for inferring this model of adaptation at the genome scale have been introduced. Here we introduce a new method, S/HIC, which uses supervised machine learning to precisely infer the location of both hard and soft selective sweeps. We show that S/HIC has unrivaled accuracy for detecting sweeps under demographic histories that are relevant to human populations, and distinguishing sweeps from linked as well as neutrally evolving regions. Moreover, we show that S/HIC is uniquely robust among its competitors to model misspecification. Thus, even if the true demographic model of a population differs catastrophically from that specified by the user, S/HIC still retains impressive discriminatory power. Finally, we apply S/HIC to the case of resequencing data from human chromosome 18 in a European population sample, and demonstrate that we can reliably recover selective sweeps that have been identified earlier using less specific and sensitive methods.

  8. Oxide vapor distribution from a high-frequency sweep e-beam system

    Science.gov (United States)

    Chow, R.; Tassano, P. L.; Tsujimoto, N.

    1995-03-01

    Oxide vapor distributions have been determined as a function of operating parameters of a high frequency sweep e-beam source combined with a programmable sweep controller. We will show which parameters are significant, the parameters that yield the broadest oxide deposition distribution, and the procedure used to arrive at these conclusions. A design-of-experimental strategy was used with five operating parameters: evaporation rate, sweep speed, sweep pattern (pre-programmed), phase speed (azimuthal rotation of the pattern), profile (dwell time as a function of radial position). A design was chosen that would show which of the parameters and parameter pairs have a statistically significant effect on the vapor distribution. Witness flats were placed symmetrically across a 25 inches diameter platen. The stationary platen was centered 24 inches above the e-gun crucible. An oxide material was evaporated under 27 different conditions. Thickness measurements were made with a stylus profilometer. The information will enable users of the high frequency e-gun systems to optimally locate the source in a vacuum system and understand which parameters have a major effect on the vapor distribution.

  9. I/O-Optimal Distribution Sweeping on Private-Cache Chip Multiprocessors

    DEFF Research Database (Denmark)

    Ajwani, Deepak; Sitchinava, Nodar; Zeh, Norbert

    2011-01-01

    The parallel external memory (PEM) model has been used as a basis for the design and analysis of a wide range of algorithms for private-cache multi-core architectures. As a tool for developing geometric algorithms in this model, a parallel version of the I/O-efficient distribution sweeping framew...

  10. Wind turbine rotor blade with in-plane sweep and devices using same, and methods for making same

    Science.gov (United States)

    Wetzel, Kyle Kristopher

    2008-03-18

    A wind turbine includes a rotor having a hub and at least one blade having a torsionally rigid root, an inboard section, and an outboard section. The inboard section has a forward sweep relative to an elastic axis of the blade and the outboard section has an aft sweep.

  11. Wind turbine rotor blade with in-plane sweep and devices using the same, and methods for making the same

    Science.gov (United States)

    Wetzel, Kyle Kristopher

    2014-06-24

    A wind turbine includes a rotor having a hub and at least one blade having a torsionally rigid root, an inboard section, and an outboard section. The inboard section has a forward sweep relative to an elastic axis of the blade and the outboard section has an aft sweep.

  12. Population and Coherence Transfer Induced by Double Frequency Sweeps in Half-Integer Quadrupolar Spin Systems

    Science.gov (United States)

    Iuga, Dinu; Schäfer, Hartmut; Verhagen, Rieko; Kentgens, Arno P. M.

    2000-12-01

    We have recently shown that the sensitivity of single- and multiple-quantum NMR experiments of half-integer (N/2) quadrupolar nuclei can be increased significantly by introducing so-called double frequency sweeps (DFS) in various pulse schemes. These sweeps consist of two sidebands generated by an amplitude modulation of the RF carrier. Using a time-dependent amplitude modulation the sidebands can be swept through a certain frequency range. Inspired by the work of Vega and Naor (J. Chem. Phys. 75, 75 (1981)), this is used to manipulate ±(m - 1) ↔ ±m (3/2 ≤ m ≤ N/2) satellite transitions in half-integer spin systems simultaneously. For 23Na (I = 3/2) and 27Al (I = 5/2) spins in single crystals it proved possible to transfer the populations of the outer ±m spin levels to the inner ±1/2 spin levels. A detailed analysis shows that the efficiency of this process is a function of the adiabaticity with which the various spin transitions are passed during the sweep. In powders these sweep parameters have to be optimized to satisfy the appropriate conditions for a maximum of spins in the powder distribution. The effects of sweep rate, sweep range, and RF field strength are investigated both numerically and experimentally. Using a DFS as a preparation period leads to significantly enhanced central transition powder spectra under both static and MAS conditions, compared to single pulse excitation. DFSs prove to be very efficient tools not only for population transfer, but also for coherence transfer. This can be exploited for the multiple- to single-quantum transfer in MQMAS experiments. It is demonstrated, theoretically and experimentally, that DFSs are capable of transferring both quintuple-quantum and triple-quantum coherence into single-quantum coherence in I = 5/2 spin systems. This leads to a significant enhancement in signal-to-noise ratio and strongly reduces the RF power requirement compared to pulsed MQMAS experiments, thus extending their applicability

  13. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Nicholas Takach; Kaveh Ashenayi

    2004-01-31

    Final design of the mast was completed (Task 5). The mast is consisting of two welded plate girders, set next to each other, and spaced 14-inches apart. Fabrication of the boom will be completed in two parts solely for ease of transportation. The end pivot connection will be made through a single 2-inch diameter x 4 feet-8 inch long 316 SS bar. During installation, hard piping make-ups using Chiksan joints will connect the annular section and 4-inch return line to allow full movement of the mast from horizontal to vertical. Additionally, flexible hoses and piping will be installed to isolate both towers from piping loads and allow recycling operations respectively. Calibration of the prototype Foam Generator Cell has been completed and experiments are now being conducted. We were able to generate up to 95% quality foam. Work is currently underway to attach the Thermo-Haake RS300 viscometer and install a view port with a microscope to measure foam bubble size and bubble size distribution. Foam rheology tests (Task 13) were carried out to evaluate the rheological properties of the proposed foam formulation. After successful completion of the first foam test, two sets of rheological tests were conducted at different foam flow rates while keeping other parameters constant (100 psig, 70F, 80% quality). The results from these tests are generally in agreement with the previous foam tests done previously during Task 9. However, an unanticipated observation during these tests was that in both cases, the frictional pressure drop in 2 inch pipe was lower than that in the 3 inch and 4 inch pipes. We also conducted the first foam cuttings transport test during this quarter. Experiments on aerated fluids without cuttings have been completed in ACTF (Task 10). Gas and liquid were injected at different flow rates. Two different sets of experiments were carried out, where the only difference was the temperature. Another set of tests was performed, which covered a wide range of

  14. Vortex cutting in superconductors

    Science.gov (United States)

    Glatz, A.; Vlasko-Vlasov, V. K.; Kwok, W. K.; Crabtree, G. W.

    2016-08-01

    Vortex cutting and reconnection is an intriguing and still-unsolved problem central to many areas of classical and quantum physics, including hydrodynamics, astrophysics, and superconductivity. Here, we describe a comprehensive investigation of the crossing of magnetic vortices in superconductors using time dependent Ginsburg-Landau modeling. Within a macroscopic volume, we simulate initial magnetization of an anisotropic high temperature superconductor followed by subsequent remagnetization with perpendicular magnetic fields, creating the crossing of the initial and newly generated vortices. The time resolved evolution of vortex lines as they approach each other, contort, locally conjoin, and detach, elucidates the fine details of the vortex-crossing scenario under practical situations with many interacting vortices in the presence of weak pinning. Our simulations also reveal left-handed helical vortex instabilities that accompany the remagnetization process and participate in the vortex crossing events.

  15. Are sweep net sampling and pitfall trapping compatible with molecular analysis of predation?

    Science.gov (United States)

    Harwood, James D

    2008-08-01

    Molecular analysis of predation enables accurate and reliable elucidation of trophic linkages in complex food webs, but identifying the strength of such interactions can be subject to error. Currently two techniques dominate: monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). Although the optimization and characterization of these systems ensures their sensitivity and specificity, predator collection protocols such as sweep-netting and vacuum sampling could overestimate feeding rates because of surface-level contamination, yielding positive reactivity or predation within the sampling device. Therefore, two sampling techniques (sweep-net sampling and hand collection) were compared within an alfalfa agroecosystem using a monoclonal antibody-based ELISA to test the hypothesis that cross-contamination is a source of error, i.e., significantly more predators (linyphiid spiders) would test positive for prey (Diptera) proteins. A concurrent study examining the viability of trapping predators into saline solution was also undertaken. No significant differences were found between the proportions of spiders screening positive for Diptera when collected by sweep-net versus hand collection, rejecting the hypothesis that sweep-netting predators for subsequent molecular gut content analysis overestimates predation frequency. ELISA was also capable of detecting prey proteins in predator guts from pitfall traps containing phosphate-buffered saline, indicating the suitability of this approach for the collection and analysis of epigeal predators. Although these results indicate that sweep netting and pitfall trapping into solution is appropriate in this predator-prey and ELISA analysis system, caution should be exercised with other interactions and PCR-based analysis. The likelihood for false-positive reactivity should therefore be considered on a case-by-case basis.

  16. Laser Cutting of Different Materials

    Directory of Open Access Journals (Sweden)

    Kadir ÇAVDAR

    2013-08-01

    Full Text Available In this paper; in general potential developments and trends of a particular machining field by extensively evaluating present studies of laser beam machining have been discussed. As it is indicated below, technical literatures have been subsumed under five major headlines: Experimental studies, reviews, optimization researches of the cutting parameters, theoretical modelling studies of laser beam cutting and academic studies relating to laser cutting

  17. CALCULATION OF LASER CUTTING COSTS

    Directory of Open Access Journals (Sweden)

    Bogdan Nedic

    2016-09-01

    Full Text Available The paper presents description methods of metal cutting and calculation of treatment costs based on model that is developed on Faculty of mechanical engineering in Kragujevac. Based on systematization and analysis of large number of calculation models of cutting with unconventional methods, mathematical model is derived, which is used for creating a software for calculation costs of metal cutting. Software solution enables resolving the problem of calculating the cost of laser cutting, comparison' of costs made by other unconventional methods and provides documentation that consists of reports on estimated costs.

  18. NoSWEEP Technology for Wire bonding Applications%引线键合应用中的无延伸技术

    Institute of Scientific and Technical Information of China (English)

    HuiWang; DaveDeGrappo

    2003-01-01

    NoSWEEP is a technology to prevent wire sweep and/or sway during molding process. This technology includes unique material, equipment and process to provide cost-effective method which can be easily implemented on current production process.

  19. Dominus for cut flower production

    Science.gov (United States)

    Fumigation with methyl bromide was the principal method of soilborne pest control in cut flower production. Many cut flower growers in Florida have ceased production, but those that remain are restricted in the fumigants that they are able to utilize due to proximity to potable water sources and oc...

  20. Will Intel Grow Through Cuts?

    Institute of Scientific and Technical Information of China (English)

    DAN; STEINBOCK

    2006-01-01

    Short-term cuts, perhaps, but long-term growth in China may be inevitable T he world's largest chipmaker, Intel, is sending a ripple effect through its pool of labor globally, including in China, with the announcement of deep workforce cuts.

  1. Rimbaud Cut-Up Burroughs

    Directory of Open Access Journals (Sweden)

    Mauricio Vasconcelos

    1996-10-01

    Full Text Available O objetivo deste ensaio é o de explorar a relação entre a poesia de Rimbaud e as experiências de William Burroughs com os cut-ups. A influência de Rimbaud sobre o trabalho de Burroughs se estende, contudo, para além dos cut-ups, envolvendo sua escrita ficcional.

  2. OPTIMAL CONTROL OF CNC CUTTING PROCESS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The intelligent optimizing method of cutting parameters and the cutting stable districts searching method are set up. The cutting parameters of each cutting pass could be optimized automatically, the cutting chatter is predicted through setting up the dynamic cutting force AR(2) model on-line, the spindle rotation speed is adjusted according to the predicting results so as to ensure the cutting system work in stable district.

  3. Online Cake Cutting (published version)

    CERN Document Server

    Walsh, Toby

    2011-01-01

    We propose an online form of the cake cutting problem. This models situations where agents arrive and depart during the process of dividing a resource. We show that well known fair division procedures like cut-and-choose and the Dubins-Spanier moving knife procedure can be adapted to apply to such online problems. We propose some fairness properties that online cake cutting procedures can possess like online forms of proportionality and envy-freeness. We also consider the impact of collusion between agents. Finally, we study theoretically and empirically the competitive ratio of these online cake cutting procedures. Based on its resistance to collusion, and its good performance in practice, our results favour the online version of the cut-and-choose procedure over the online version of the moving knife procedure.

  4. Cutting forces in orthogonal cutting of unidirectional GFRP composites

    Energy Technology Data Exchange (ETDEWEB)

    Caprino, G.; Nele, L. [Univ. of Naples Federico II (Italy). Dept. of Materials and Production Engineering

    1996-07-01

    The results of orthogonal cutting tests carried out on unidirectional glass fiber reinforced plastic composites, using HSS tools, are presented and discussed. During the tests, performed on a milling machine at very low cutting speed to avoid thermal effects, the cutting speed was held constant and parallel to the fiber direction. Three parameters, namely the tool rake angle {alpha}, the tool relief angle {gamma}, and the depth of cut t, were varied. According to the experimental results, the horizontal force per unit width, F{sub hu}, undergoes a dramatic decrease, never verified for metals, with increasing {alpha}. Besides, F{sub hu} is only negligibly affected by the relief angle, and linearly increases with t. Similarly to metals, an effect of the depth of cut on the specific energy (size effect) is found also for composites. However, the presented results indicate that the size effect can be analytically modeled in a simple way in the case of composites. The vertical force per unit width, F{sub vu}, exhibits a marked reduction when the relief angle is increased. F{sub vu} is also very sensitive to the rake angle: the lower {alpha}, the higher is F{sub vu}. It is shown that this behavior probably reflects a strong influence of the rake angle on the forces developing at the flank. A linear dependence of the vertical force on the depth of cut is also demonstrated. Finally, the experimental data are utilized to obtain empirical formulae, allowing an approximate evaluation of cutting forces.

  5. OCT based on multi-frequency sweeping Fizeau interferometer with phase modulating method

    Science.gov (United States)

    Choi, S.; Watanabe, T.; Sasaki, O.; Suzuki, T.

    2013-09-01

    The Multi-frequency sweeping Fizeau-type interferometer (MFS-FI) for optical coherence tomography (OCT) is demonstrated. The multi-frequency sweeping by a variable Fabry-Perot filter permits detection of high-order low-coherence interferometric signals in the Fizeau interferometer. The sinusoidal phase modulation technique was utilized to detect accurate interference amplitude and phase distributions of back scattered light from surfaces of a sample. OCT measurements by the MFS-FI were conducted for vibrating glass plates with a frequency of 1 kHz, and cellular tissues fixed with formalin and embedded in paraffin. The tomographic 3-dimensional volume and cross-sectional surface displacements were detected with an accuracy of nano-meters.

  6. A theory of dropwise condensation at large subcooling including the effect of the sweeping

    Science.gov (United States)

    Yamali, C.; Merte, H., Jr.

    The effect of sweeping by the departing droplets on the heat transfer coefficient in dropwise condensation is studied analytically here. Using basic principles, an analytical model for dropwise condensation is devised, which takes into account the elementary processes that make up the dropwise condensation cycle. The analysis is divided into two parts: in the first part, the heat transfer as a result of nucleation and coalescing of the droplets is considered. In the second part, the effect of sweeping is introduced. The results are presented as the variation of nondimensional heat flux versus the distance from the upper edge of the condenser surface at various surface subcoolings. Calculations show that the variation of heat flux with surface subcooling is linear only at small values of subcooling. As the subcooling is increased the slope of the mean heat flux versus subcooling curve decreases, and for a sufficiently high body force passes through a maximum.

  7. A novel methodology for determining low-cost fine particulate matter street sweeping routes.

    Science.gov (United States)

    Blazquez, Carola A; Beghelli, Alejandra; Meneses, Veronica P

    2012-02-01

    This paper addresses the problem of low-cost PM10 (particulate matter with aerodynamic diameter arc routing problem into a node routing problem is proposed in this paper. This is accomplished by building a graph that represents the area to sweep in such a way that the problem can be solved by applying any known solution to the Traveling Salesman Problem (TSP). As a way of illustration, the proposed method was applied to the northeast area of the Municipality of Santiago (Chile). Results show that the proposed methodology achieved up to 37% savings in kilometers traveled by the sweeping vehicle when compared to the solution obtained by solving the TSP problem with Geographic Information Systems (GIS)--aware tools.

  8. On the effects of nonlinearities in room impulse response measurements with exponential sweeps

    DEFF Research Database (Denmark)

    Ciric, Dejan; Markovic, Milos; Mijic, Miomir

    2013-01-01

    In room impulse response measurements, there are some common disturbances that affect the measured results. These disturbances include nonlinearity, noise and time variance. In this paper, the effects of nonlinearities in the measurements with exponential sweep-sine signals are analyzed from...... different perspectives. The analysis combines theoretical approach, simulations and measurements. The focus is on distortion artifacts in the causal part of the impulse response and their effects on room acoustical parameters. The results show that the sweep-sine method is vulnerable to a certain extent...... to nonlinearities from a theoretical standpoint, but the consequences of this vulnerability are reduced in the responses measured in practice. However, due to irretrievable contamination of the impulse responses, the nonlinearities (especially strong ones) should be avoided....

  9. Rapid and broad wavelength sweeping of standard telecommunication distributed feedback laser diode.

    Science.gov (United States)

    Njegovec, Matej; Donlagic, Denis

    2013-06-01

    This Letter presents a method for the fast and broad wavelength sweeping of a standard setup of a diode's active region and its immediate vicinity, which contain the diode's optical feedback system. The selective and rapid heating of the active region is possible due to the confinement of the voltage drop to the active diode's region that has submicrometer thickness. Using the presented method and an off-the-shelf telecommunication distributed feedback laser diode, we demonstrate wavelength sweeps in excess of 10 nm that were completed in about 200 ns, while generating average optical power in excess of 50 mW. In spite of high-amplitude current-drive pulses, 6000 h continuous operation of the diode within such an operational regime did not show any significant degradation of the diode's performance.

  10. Sweeping Jet Actuators - A New Design Tool for High Lift Generation

    Science.gov (United States)

    Graff, Emilio; Seele, Roman; Lin, John C.; Wygnanski, Israel

    2013-01-01

    Active Flow Control (AFC) experiments performed at the Caltech Lucas Wind Tunnel on a generic airplane vertical tail model proved the effectiveness of sweeping jets in improving the control authority of a rudder. The results indicated that a momentum coefficient (C(sub u)) of approximately 2% increased the side force in excess of 50% at the maximum conventional rudder deflection angle in the absence of yaw. However, sparsely distributed actuators providing a collective C(sub u) approx. = 0.1% were able to increase the side force in excess of 20%. This result is achieved by reducing the spanwise flow along the swept back rudder and its success is attributed to the large sweep back angle of the vertical tail. This current effort was sponsored by the NASA Environmentally Responsible Aviation (ERA) project.

  11. Analysing Infinite-State Systems by Combining Equivalence Reduction and the Sweep-Line Method

    DEFF Research Database (Denmark)

    Mailund, Thomas

    2002-01-01

    The sweep-line method is a state space exploration method for on-the-fly verification aimed at systems exhibiting progress. Presence of progress in the system makes it possible to delete certain states during state space generation, which reduces the memory used for storing the states. Unfortunat......The sweep-line method is a state space exploration method for on-the-fly verification aimed at systems exhibiting progress. Presence of progress in the system makes it possible to delete certain states during state space generation, which reduces the memory used for storing the states....... Unfortunately, the same progress that is used to improve memory performance in state space exploration often leads to an infinite state space: The progress in the system is carried over to the states resulting in infinitely many states only distinguished through the progress. A finite state space can...

  12. Exact transition probabilities for a linear sweep through a Kramers-Kronig resonance

    Science.gov (United States)

    Sun, Chen; Sinitsyn, N. A.

    2015-12-01

    We consider a localized electronic spin controlled by a circularly polarized optical beam and an external magnetic field. When the frequency of the beam is tuned near an optical resonance with a continuum of higher energy states, effective magnetic fields are induced on the two-level system via the inverse Faraday effect. We explore the process in which the frequency of the beam is made linearly time-dependent so that it sweeps through the optical resonance, starting and ending at the values far away from it. In addition to changes of spin states, Kramers-Kronig relations guarantee that a localized electron can also escape into a continuum of states. We argue that probabilities of transitions between different possible electronic states after such a sweep of the optical frequency can be found exactly, regardless the shape of the resonance. We also discuss extension of our results to multistate systems.

  13. Theory of linear sweep voltammetry with diffuse charge: unsupported electrolytes, thin films, and leaky membranes

    CERN Document Server

    Yan, David; Pugh, Mary C; Dawson, Francis P

    2016-01-01

    Linear sweep and cyclic voltammetry techniques are important tools for electrochemists and have a variety of applications in engineering. Voltammetry has classically been treated with the Randles-Sevcik equation, which assumes an electroneutral supported electrolyte. No general theory of linear-sweep voltammetry is available, however, for unsupported electrolytes and for other situations where diffuse charge effects play a role. In this paper, we provide a historical review of previous models and experiments and present a comprehensive mathematical theory of voltammetry in electrochemical cells with diffuse charge. We solve the time-dependent Poisson-Nernst-Planck (PNP) equations with generalized Frumkin-Butler-Volmer (FBV) boundary conditions, and show theoretical and simulated current-voltage curves for liquid and solid thin films, cells with blocking electrodes, and membranes with fixed background charge. The full range of dimensionless parameters is considered, including the dimensionless Debye screening ...

  14. Reducing Sweeping Frequencies in Microwave NDT Employing Machine Learning Feature Selection

    Directory of Open Access Journals (Sweden)

    Abdelniser Moomen

    2016-04-01

    Full Text Available Nondestructive Testing (NDT assessment of materials’ health condition is useful for classifying healthy from unhealthy structures or detecting flaws in metallic or dielectric structures. Performing structural health testing for coated/uncoated metallic or dielectric materials with the same testing equipment requires a testing method that can work on metallics and dielectrics such as microwave testing. Reducing complexity and expenses associated with current diagnostic practices of microwave NDT of structural health requires an effective and intelligent approach based on feature selection and classification techniques of machine learning. Current microwave NDT methods in general based on measuring variation in the S-matrix over the entire operating frequency ranges of the sensors. For instance, assessing the health of metallic structures using a microwave sensor depends on the reflection or/and transmission coefficient measurements as a function of the sweeping frequencies of the operating band. The aim of this work is reducing sweeping frequencies using machine learning feature selection techniques. By treating sweeping frequencies as features, the number of top important features can be identified, then only the most influential features (frequencies are considered when building the microwave NDT equipment. The proposed method of reducing sweeping frequencies was validated experimentally using a waveguide sensor and a metallic plate with different cracks. Among the investigated feature selection techniques are information gain, gain ratio, relief, chi-squared. The effectiveness of the selected features were validated through performance evaluations of various classification models; namely, Nearest Neighbor, Neural Networks, Random Forest, and Support Vector Machine. Results showed good crack classification accuracy rates after employing feature selection algorithms.

  15. Sweep potential deposition of Tm-Ni-Co alloy films in dimethylsulfoxide

    Institute of Scientific and Technical Information of China (English)

    YUAN Dingsheng; LIU Yingliang; ZHANG Jingxian; LIU Guankun; TONG Yexiang

    2004-01-01

    The Tm-Ni-Co alloy films have been prepared by the sweep potential deposition technique. The surface appearance of Tm-Ni-Co alloy films was silver, smooth and adhesive. The surfaces of Tm-Ni-Co alloy films observed by scanning electron microscope (SEM) were uniform, adhesive and compact. The sizes of metallic grains were about 80-100 nm, 100-200 amorphous as proven by the X-ray diffraction (XRD).

  16. Reducing Sweeping Frequencies in Microwave NDT Employing Machine Learning Feature Selection.

    Science.gov (United States)

    Moomen, Abdelniser; Ali, Abdulbaset; Ramahi, Omar M

    2016-04-19

    Nondestructive Testing (NDT) assessment of materials' health condition is useful for classifying healthy from unhealthy structures or detecting flaws in metallic or dielectric structures. Performing structural health testing for coated/uncoated metallic or dielectric materials with the same testing equipment requires a testing method that can work on metallics and dielectrics such as microwave testing. Reducing complexity and expenses associated with current diagnostic practices of microwave NDT of structural health requires an effective and intelligent approach based on feature selection and classification techniques of machine learning. Current microwave NDT methods in general based on measuring variation in the S-matrix over the entire operating frequency ranges of the sensors. For instance, assessing the health of metallic structures using a microwave sensor depends on the reflection or/and transmission coefficient measurements as a function of the sweeping frequencies of the operating band. The aim of this work is reducing sweeping frequencies using machine learning feature selection techniques. By treating sweeping frequencies as features, the number of top important features can be identified, then only the most influential features (frequencies) are considered when building the microwave NDT equipment. The proposed method of reducing sweeping frequencies was validated experimentally using a waveguide sensor and a metallic plate with different cracks. Among the investigated feature selection techniques are information gain, gain ratio, relief, chi-squared. The effectiveness of the selected features were validated through performance evaluations of various classification models; namely, Nearest Neighbor, Neural Networks, Random Forest, and Support Vector Machine. Results showed good crack classification accuracy rates after employing feature selection algorithms.

  17. The Effects of Sweeping Jet Actuator Parameters on Flow Separation Control

    Science.gov (United States)

    Koklu, Mehti

    2015-01-01

    A parametric experimental study was performed with sweeping jet actuators (fluidic oscillators) to determine their effectiveness in controlling flow separation on an adverse pressure gradient ramp. Actuator parameters that were investigated include blowing coefficients, operation mode, pitch and spreading angles, streamwise location, aspect ratio, and scale. Surface pressure measurements and surface oil flow visualization were used to characterize the effects of these parameters on the actuator performance. 2D Particle Image Velocimetry measurements of the flow field over the ramp and hot-wire measurements of the actuator's jet flow were also obtained for selective cases. In addition, the sweeping jet actuators were compared to other well-known flow control techniques such as micro-vortex generators, steady blowing, and steady vortex-generating jets. The results confirm that the sweeping jet actuators are more effective than steady blowing and steady vortex-generating jets. The results also suggest that an actuator with a larger spreading angle placed closer to the location where the flow separates provides better performance. For the cases tested, an actuator with an aspect ratio, which is the width/depth of the actuator throat, of 2 was found to be optimal. For a fixed momentum coefficient, decreasing the aspect ratio to 1 produced weaker vortices while increasing the aspect ratio to 4 reduced coverage area. Although scaling down the actuator (based on the throat dimensions) from 0.25 inch x 0.125 inch to 0.15 inch x 0.075 inch resulted in similar flow control performance, scaling down the actuator further to 0.075 inch x 0.0375 inch reduced the actuator efficiency by reducing the coverage area and the amount of mixing in the near-wall region. The results of this study provide insight that can be used to design and select the optimal sweeping jet actuator configuration for flow control applications.

  18. Cyclic Voltammetry And Linear Sweep Voltammetry Study Of Cyclic Tertiary Amines

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ping; TIAN JinPing; YIN YingWu

    2001-01-01

    @@ Cyclic six membered a-aminonitrile have proved to be very versatile synthetic intermediates and have been widely used in the construction of a large number of indole alkaloids. In order to obtain some information about the mechanisn of electrochemical synthesis of aaminonitrile. Electrochemistry behaviors that include cyclic voltammetry and linear sweep voltammetry of cyclic tertiary amines which including N-benzylpiperidine (NBP), 1-(l-Methoxycarbonyl ethyl) piperidine (MCEP), N-methylcarbonylppiperidine (NMCP), Nethylpiperidine(NEP) was studied.

  19. Cyclic Voltammetry And Linear Sweep Voltammetry Study Of Cyclic Tertiary Amines

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Ping

    2001-01-01

    Cyclic six membered a-aminonitrile have proved to be very versatile synthetic intermediates and have been widely used in the construction of a large number of indole alkaloids. In order to obtain some information about the mechanisn of electrochemical synthesis of aaminonitrile. Electrochemistry behaviors that include cyclic voltammetry and linear sweep voltammetry of cyclic tertiary amines which including N-benzylpiperidine (NBP), 1-(l-Methoxycarbonyl ethyl) piperidine (MCEP), N-methylcarbonylppiperidine (NMCP), Nethylpiperidine(NEP) was studied.……

  20. Study of Near-Stall Flow Behavior in a Modern Transonic Fan with Composite Sweep

    Science.gov (United States)

    Hah, Chunill; Shin, Hyoun-Woo

    2011-01-01

    Detailed flow behavior in a modern transonic fan with a composite sweep is investigated in this paper. Both unsteady Reynolds-averaged Navier-Stokes (URANS) and Large Eddy Simulation (LES) methods are applied to investigate the flow field over a wide operating range. The calculated flow fields are compared with the data from an array of high-frequency response pressure transducers embedded in the fan casing. The current study shows that a relatively fine computational grid is required to resolve the flow field adequately and to calculate the pressure rise across the fan correctly. The calculated flow field shows detailed flow structure near the fan rotor tip region. Due to the introduction of composite sweep toward the rotor tip, the flow structure at the rotor tip is much more stable compared to that of the conventional blade design. The passage shock stays very close to the leading edge at the rotor tip even at the throttle limit. On the other hand, the passage shock becomes stronger and detaches earlier from the blade passage at the radius where the blade sweep is in the opposite direction. The interaction between the tip clearance vortex and the passage shock becomes intense as the fan operates toward the stall limit, and tip clearance vortex breakdown occurs at near-stall operation. URANS calculates the time-averaged flow field fairly well. Details of measured RMS static pressure are not calculated with sufficient accuracy with URANS. On the other hand, LES calculates details of the measured unsteady flow features in the current transonic fan with composite sweep fairly well and reveals the flow mechanism behind the measured unsteady flow field.

  1. Numerical and performance analysis of one row transonic rotor with sweep and lean angle

    Science.gov (United States)

    Razavi, Seyed Reza; Boroomand, Masoud

    2014-10-01

    In this study, aerodynamic behaviors of swept and leaned blades were investigated. Axial and tangential blade curvatures impacts on compressor's operating parameters were analyzed separately. A commercial CFD program which solves the Reynolds-averaged Navier-Stokes equations was used to find out the mentioned impact and the complicated flow field of transonic compressor-rotors. The CFD method that was used for solving flow field's equation was validated by experimental data of NASA Rotor 67. The results showed that the compressor with curved rotors had higher efficiency, rotor pressure ratio and stable operating range compared to the compressor with un-curved rotors. Using curved rotors mostly had higher impact on the overall stable operating range compared to the other operating parameters. Operating range involves choking point and stall point that were changed separately by using of bended blade. For finding the detailed impact of sweep and lean angle on transonic blades, various forms of lean and sweep angles were exerted to basic rotor. It was found that sweep angles increased overall operating range up to 30%, efficiency up to 2% and pressure ratio up to 1%. Leaning the blades increased the safe operating range, the pressure ratio and efficiency by 14%, 4% and 2% respectively.

  2. Derivation of Incident Angle and Sweeping Voltage Design on Advanced Ionospheric Probe onboard FORMOSAT-5

    Science.gov (United States)

    Lin, Z. W.; Chao, C. K.; Chang, Y. S.

    2014-12-01

    Advanced Ionospheric Probe (AIP) developed by the National Central University (NCU), Taiwan, has been selected to install on FORMOSAT-5 satellite. It is an all-in-one plasma sensor with the sampling rate up to 8,192 Hz to measure ionospheric plasma concentrations, velocities, and temperatures over a wide range of spatial scales. The design of AIP sensor allows it to sequentially perform as a Retarding Potential Analyzer (RPA), an Ion Drift Meter (IDM), an Ion Trap (IT), or a Planer Langmuir Probe (PLP). Unlike the inherited payload IPEI onboard FORMOSAT-1/ROCSAT-1, the entrance opening of IDM of AIP is circular instead of square shape, causes the difference in the geometry calculation of the projection area. New method is present to obtain the incident angle from the incoming plasma beam. Meanwhile, a set of sweeping voltage pattern is defined to get a better result of plasma parameters from RPA function. Upon the requirement of the mission, several sweeping voltage patterns are designed to fit the specified species of plasma to increase the accuracy in the derivation of ram speed and temperature. A simulation is present to show the fitting result in different assumptions and conditions for each sweeping pattern.

  3. Observational Test for a Random Sweeping Model in Solar Wind Turbulence.

    Science.gov (United States)

    Perschke, C; Narita, Y; Motschmann, U; Glassmeier, K H

    2016-03-25

    Evidence of frequency broadening at ion kinetic scales due to large-scale eddies and waves is found in solar wind turbulence by a test for a random sweeping model using the magnetic energy spectrum in the frequency vs wave number domain in the comoving frame of the flow obtained from multispacecraft observations. The statistical analysis of the frequency vs wave number spectra without using Taylor's hypothesis shows Gaussian frequency broadening around nearly zero frequencies that increases for larger wave numbers and non-Gaussian tails at higher frequencies. Comparison of the observed frequency broadening with a random sweeping model derived from hydrodynamic turbulence reveals similarities with respect to the Gaussian shape. The standard deviation of the broadening scales with ∼k^{1.6±0.2} and differs from the hydrodynamic turbulence model that predicts ∼k^{2/3}. We interpret this stronger increasing broadening as a consequence of the more diverse large scale structures (eddies and waves) in plasma turbulence and the accompanied more complex sweeping. Consequently, an identification and association of waves with normal modes based on their dispersion relation only, in particular at ion kinetic scales and below, is not possible in solar wind turbulence.

  4. "Paper Cut Lady" Ku Shulan

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    WHEN the people in Xunyi County of Shaanxi Province talk about the traditional paper cut, they always speak of a "paper cut lady" Ku Shulan. Her works have been shown at the Xi’an Artists’ Gallery, Beijing China Art Gallery and Exhibition Hall of Central Academy of Fine Arts. Almost seventy years old, Ku Shulan is an ordinary country lady, and her artistic achievements were closely linked with her mother countryside. The traditional paper cut created and developed in Xunyi County, has a simple and bold style of Northern Shaanxi, and an exquisitely

  5. Phaco sweep.

    Science.gov (United States)

    Gimbel, H V; Chin, P K

    1995-09-01

    We present a variation on a technique for down slope sculpting designed to enhance the safety of sculpting deeply in the central nucleus. The phaco tip moves laterally to remove very deep nuclear material, increasing visualization with less risk of occlusion and break through to the capsule.

  6. High Efficiency, Digitally Calibrated TR Modules Enabling Lightweight SweepSAR Architectures for DESDynI-Class Radar Instruments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop and demonstrate a next-generation digitally calibrated, highly scalable, L-band Transmit/Receive (TR) module to enable a precision beamforming SweepSAR...

  7. Megahertz FDML Laser with up to 143nm Sweep Range for Ultrahigh Resolution OCT at 1050nm

    CERN Document Server

    Kolb, Jan Philip; Eibl, Mattias; Pfeiffer, Tom; Wieser, Wolfgang; Huber, Robert

    2016-01-01

    We present a new design of a Fourier Domain Mode Locked laser (FDML laser), which provides a new record in sweep range at ~1um center wavelength: At the fundamental sweep rate of 2x417 kHz we reach 143nm bandwidth and 120nm with 4x buffering at 1.67MHz sweep rate. The latter configuration of our system is characterized: The FWHM of the point spread function (PSF) of a mirror is 5.6um (in tissue). Human in vivo retinal imaging is performed with the MHz laser showing more details in vascular structures. Here we could measure an axial resolution of 6.0um by determining the FWHM of specular reflex in the image. Additionally, challenges related to such a high sweep bandwidth such as water absorption are investigated.

  8. Megahertz FDML laser with up to 143nm sweep range for ultrahigh resolution OCT at 1050nm

    Science.gov (United States)

    Kolb, Jan Philip; Klein, Thomas; Eibl, Matthias; Pfeiffer, Tom; Wieser, Wolfgang; Huber, Robert

    2016-03-01

    We present a new design of a Fourier Domain Mode Locked laser (FDML laser), which provides a new record in sweep range at ~1μm center wavelength: At the fundamental sweep rate of 2x417 kHz we reach 143nm bandwidth and 120nm with 4x buffering at 1.67MHz sweep rate. The latter configuration of our system is characterized: The FWHM of the point spread function (PSF) of a mirror is 5.6μm (in tissue). Human in vivo retinal imaging is performed with the MHz laser showing more details in vascular structures. Here we could measure an axial resolution of 6.0μm by determining the FWHM of specular reflex in the image. Additionally, challenges related to such a high sweep bandwidth such as water absorption are investigated.

  9. AHM cutting expenses, adding technology.

    Science.gov (United States)

    Lutz, S

    1990-04-30

    American Healthcare Management, emerging from bankruptcy protection is cutting corporate costs and expanding into new technology to attract more private-paying patients and lessen dependence on Medicare business.

  10. Refrigerated cutting tools improve machining of superalloys

    Science.gov (United States)

    Dudley, G. M.

    1971-01-01

    Freon-12 applied to tool cutting edge evaporates quickly, leaves no residue, and permits higher cutting rate than with conventional coolants. This technique increases cutting rate on Rene-41 threefold and improves finish of machined surface.

  11. Process for separating carbon dioxide from flue gas using sweep-based membrane separation and absorption steps

    Science.gov (United States)

    Wijmans, Johannes G.; Baker, Richard W.; Merkel, Timothy C.

    2012-08-21

    A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves routing a first portion of the flue gas stream to be treated to an absorption-based carbon dioxide capture step, while simultaneously flowing a second portion of the flue gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.

  12. Optimization of Cutting Variables in Machining

    Institute of Scientific and Technical Information of China (English)

    Zhang Xueyan; Wu Zhenye; Zhou Guohua

    1996-01-01

    With the three criteria for cutting variables proposed by W. W. Gilbert and K.Hitomi, th is paper analyzes the reasonable selection of cutting variables, and further states the relations among maximum profit-oriented cutting speed,minimum cost-oriented cutting speed and maximum productivity-oriented cutting speed. It puts forward a mathematical model for the optimization of cutting variables in machining.

  13. Evaluation of the hemostatic and coagulation effects of AUTO CUT and DRY CUT using a computer-controlled cutting system.

    Science.gov (United States)

    Szyrach, Mara N I; Tolba, Rene H; Voigtländer, Matthias; Neugebauer, Alexander; Enderle, Markus D

    2010-05-01

    To evaluate a newly developed computer-controlled cutting system for the generation of standardized resections and to systematically compare the hemostatic properties and tissue effect of 2 cutting modes, namely, AUTO CUT and DRY CUT used in urologic procedures. An isolated perfused kidney model was used to assess blood loss and coagulation depth after resection of tissue specimens of standardized geometry, size, and cutting velocity with a resection loop. Three different effect settings (E1, E3, and E6; 200 W) of the electrosurgical modes AUTO CUT and DRY CUT were compared. Blood loss was determined semiquantitatively by weighing a swab before and after placing it onto the resection area. The coagulation depth was estimated microscopically on cross sections. The computer-controlled cutting system creates resections of standardized geometry and size with a high reproducibility. An effect level-dependent increase in hemostasis and coagulation depth could be demonstrated with the cutting modes DRY CUT and AUTO CUT using this computer-controlled cutting system. The hemostatic effect with DRY CUT is significantly more pronounced than with AUTO CUT (E1, E3: P computer-controlled cutting system creating reproducible resections in combination with the isolated perfused kidney model offers the possibility to systematically investigate bleeding rate and coagulation depth. The stronger hemostatic properties of the DRY CUT mode are more favorable for urologic interventions requiring a higher hemostatic effect than the AUTO CUT mode. Copyright 2010 Elsevier Inc. All rights reserved.

  14. Summary of NACA/NASA Variable-Sweep Research and Development Leading to the F-111 (TFX)

    Science.gov (United States)

    1966-01-01

    On November 24, 1962, the United States ushered in a new era of aircraft development when the Department of Defense placed an initial development contract for the world's first supersonic variable-sweep aircraft - the F-111 or so-called TFX (tactical fighter-experimental). The multimission performance potential of this concept is made possible by virtue of the variable-sweep wing - a research development of the NASA and its predecessor, the NACA. With the wing swept forward into the maximum span position, the aircraft configuration is ideal for efficient subsonic flight. This provides long-range combat and ferry mission capability, short-field landing and take-off characteristics, and compatibility with naval aircraft carrier operation. With the wing swept back to about 650 of sweep, the aircraft has optimum supersonic performance to accomplish high-altitude supersonic bombing or interceptor missions. With the wing folded still further back, the aircraft provides low drag and low gust loads during supersonic flight "on the deck" (altitudes under 1000 feet). The concept of wing variable sweep, of course, is not new. Initial studies were conducted at Langley as early as 1945, and two subsonic variable-sweep prototypes (Bell X-5 and Grumman XF-IOF) were flown as early as 1951/52. These were subsonic aircraft, however, and the great advantage of variable sweep in improving supersonic flight efficiency could not be realized. Further the structures of these early aircraft were complicated by the necessity for translating the ing fore and aft to achieve satisfactory longitUdinal stability as the wing sweep was varied. Late in 1958 a research breakthrough at Langley provided the technology for designing a variable-sweep wing having satisfactory stability through a wide sweep angle range without the necessity for fore and aft translation of the wing. In this same period there evolved within the military services an urgent requirement for a versatile fighter-bomber that

  15. Cut Front Geometry Characterization in Cutting Applications of Brass with Abrasive Water Jet

    Science.gov (United States)

    Akkurt, Adnan

    2010-06-01

    Abrasive water jet (AWJ) cutting is an advanced manufacturing process for machining hard to cut materials. In this study, brass-353 samples of different thicknesses were cut by AWJ using different feed rates to identify the relationships between depth of cut (material thickness), feed rate, and deflection of cutting edge geometry. The effects of material thickness on the AWJ cut surface roughness were investigated and discussed. Deflection of cutting edge geometry in AWJ cutting process was assessed. Cutting edge geometry was characterized by analyzing the surface properties of cut samples.

  16. Steady-state sweep visual evoked potential processing denoised by wavelet transform

    Science.gov (United States)

    Weiderpass, Heinar A.; Yamamoto, Jorge F.; Salomão, Solange R.; Berezovsky, Adriana; Pereira, Josenilson M.; Sacai, Paula Y.; de Oliveira, José P.; Costa, Marcio A.; Burattini, Marcelo N.

    2008-03-01

    Visually evoked potential (VEP) is a very small electrical signal originated in the visual cortex in response to periodic visual stimulation. Sweep-VEP is a modified VEP procedure used to measure grating visual acuity in non-verbal and preverbal patients. This biopotential is buried in a large amount of electroencephalographic (EEG) noise and movement related artifact. The signal-to-noise ratio (SNR) plays a dominant role in determining both systematic and statistic errors. The purpose of this study is to present a method based on wavelet transform technique for filtering and extracting steady-state sweep-VEP. Counter-phase sine-wave luminance gratings modulated at 6 Hz were used as stimuli to determine sweep-VEP grating acuity thresholds. The amplitude and phase of the second-harmonic (12 Hz) pattern reversal response were analyzed using the fast Fourier transform after the wavelet filtering. The wavelet transform method was used to decompose the VEP signal into wavelet coefficients by a discrete wavelet analysis to determine which coefficients yield significant activity at the corresponding frequency. In a subsequent step only significant coefficients were considered and the remaining was set to zero allowing a reconstruction of the VEP signal. This procedure resulted in filtering out other frequencies that were considered noise. Numerical simulations and analyses of human VEP data showed that this method has provided higher SNR when compared with the classical recursive least squares (RLS) method. An additional advantage was a more appropriate phase analysis showing more realistic second-harmonic amplitude value during phase brake.

  17. Frequency sweep for a beam system with local unilateral contact modeling satellite solar arrays

    CERN Document Server

    Hazim, Hamad

    2009-01-01

    In order to save mass of satellite solar arrays, the flexibility of the panels becomes not negligible and they may strike each other; this may damage the structure. To prevent this, rubber snubbers are mounted at well chosen points of the structure and they act as one sided linear spring; as a negative consequence, the dynamic of these panels becomes nonlinear. The finite element approximation is used to solve partial differential equations governing the structural dynamic. Frequency sweep has been performed numerically to study the dynamic behavior. Non linear normal modes are under study

  18. Investigation on False Peak Phenomena in On-line Sweeping Technique in MEKC

    Institute of Scientific and Technical Information of China (English)

    YANG,Geng-Liang(杨更亮); LI,Bao-Hui(李保会); WANG,De-Xian(王德先); CHEN,Yi(陈义)

    2002-01-01

    In this paper, several factors that could lead to the appearance of false peak were investigated by using on-line sample sweeping technique under different experimental conditions. The tested analytes were buflomedil hydrochloride, ephedrine hydrochloride, benzyl alcohol, vanillin, p-hydroxybenzaldehyde amd mmethylphenol. Results showed that among the six compounds,three of them, i.e., buflomedil hydrochloride, ephedrine hydrochloride and benzyl alcohol will cause false peaks to appear when sample injection time is long, sodium dodecyl sulfate (SDS) concentration is high and there is pH gradient between cathode and anode. In order to avoid the appearance of false peak, the pH gradient should be avoided.

  19. Efficient cross polarization with simultaneous adiabatic frequency sweep on the source and target channels.

    Science.gov (United States)

    Peng, Weng Kung; Takeda, Kazuyuki

    2007-10-01

    In this work, we propose a new and efficient heteronuclear cross polarization scheme, in which adiabatic frequency sweeps from far off-resonance toward on-resonance are applied simultaneously on both the source and target spins. This technique, which we call as Simultaneous ADIabatic Spin-locking Cross Polarization (SADIS CP), is capable of efficiently locking both the source and target spins with moderate power even in the presence of large spectral distribution and fast relaxation. It is shown that by keeping the time-dependent Hartmann-Hahn mismatch minimal throughout the mixing period, polarization transfer can be accelerated. Experiments are demonstrated in a powder sample of L-alanine.

  20. Local hardening evaluation of carbon steels by using frequency sweeping excitation and spectrogram method

    Science.gov (United States)

    Tsuchida, Yuji; Kudo, Yuki; Enokizono, Masato

    2017-02-01

    This paper presents our proposed frequency sweeping excitation and spectrogram method (FSES method) by a magnetic sensor for non-destructive testing of hardened low carbon steels. This method can evaluate the magnetic properties of low carbon steels which were changed after induction heating treatment. It was examined by our proposed method that the degrees of yield strength of low carbon steels were varied depending on hardened conditions. Moreover, it was made clear that the maximum magnetic field strength, Hmax, derived from the measured B-H loops was very sensitive to the hardening if the surface of the samples were flat.

  1. A Sweep-Plane Algorithm for Generating Random Tuples in Simple Polytopes

    OpenAIRE

    Leydold, Josef; Hörmann, Wolfgang

    1997-01-01

    A sweep-plane algorithm by Lawrence for convex polytope computation is adapted to generate random tuples on simple polytopes. In our method an affine hyperplane is swept through the given polytope until a random fraction (sampled from a proper univariate distribution) of the volume of the polytope is covered. Then the intersection of the plane with the polytope is a simple polytope with smaller dimension. In the second part we apply this method to construct a black-box algorithm for log-conca...

  2. The Grid[Way] Job Template Manager, a tool for parameter sweeping

    Science.gov (United States)

    Lorca, Alejandro; Huedo, Eduardo; Llorente, Ignacio M.

    2011-04-01

    Parameter sweeping is a widely used algorithmic technique in computational science. It is specially suited for high-throughput computing since the jobs evaluating the parameter space are loosely coupled or independent. A tool that integrates the modeling of a parameter study with the control of jobs in a distributed architecture is presented. The main task is to facilitate the creation and deletion of job templates, which are the elements describing the jobs to be run. Extra functionality relies upon the GridWay Metascheduler, acting as the middleware layer for job submission and control. It supports interesting features like multi-dimensional sweeping space, wildcarding of parameters, functional evaluation of ranges, value-skipping and job template automatic indexation. The use of this tool increases the reliability of the parameter sweep study thanks to the systematic bookkeeping of job templates and respective job statuses. Furthermore, it simplifies the porting of the target application to the grid reducing the required amount of time and effort. Program summaryProgram title: Grid[Way] Job Template Manager (version 1.0) Catalogue identifier: AEIE_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIE_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Apache license 2.0 No. of lines in distributed program, including test data, etc.: 3545 No. of bytes in distributed program, including test data, etc.: 126 879 Distribution format: tar.gz Programming language: Perl 5.8.5 and above Computer: Any (tested on PC x86 and x86_64) Operating system: Unix, GNU/Linux (tested on Ubuntu 9.04, Scientific Linux 4.7, centOS 5.4), Mac OS X (tested on Snow Leopard 10.6) RAM: 10 MB Classification: 6.5 External routines: The GridWay Metascheduler [1]. Nature of problem: To parameterize and manage an application running on a grid or cluster. Solution method: Generation of job templates as a cross product of

  3. Linear-sweep voltammetry of a soluble redox couple in a cylindrical electrode

    Science.gov (United States)

    Weidner, John W.

    1991-01-01

    An approach is described for using the linear sweep voltammetry (LSV) technique to study the kinetics of flooded porous electrodes by assuming a porous electrode as a collection of identical noninterconnected cylindrical pores that are filled with electrolyte. This assumption makes possible to study the behavior of this ideal electrode as that of a single pore. Alternatively, for an electrode of a given pore-size distribution, it is possible to predict the performance of different pore sizes and then combine the performance values.

  4. Extensions of cutting problems: setups

    Directory of Open Access Journals (Sweden)

    Sebastian Henn

    2013-08-01

    Full Text Available Even though the body of literature in the area of cutting and packing is growing rapidly, research seems to focus on standard problems in the first place, while practical aspects are less frequently dealt with. This is particularly true for setup processes which arise in industrial cutting processes whenever a new cutting pattern is started (i.e. a pattern is different from its predecessor and the cutting equipment has to be prepared in order to meet the technological requirements of the new pattern. Setups involve the consumption of resources and the loss of production time capacity. Therefore, consequences of this kind must explicitly be taken into account for the planning and control of industrial cutting processes. This results in extensions to traditional models which will be reviewed here. We show how setups can be represented in such models, and we report on the algorithms which have been suggested for the determination of solutions of the respective models. We discuss the value of these approaches and finally point out potential directions of future research.

  5. Cutting inlays with a laser

    Science.gov (United States)

    Swaczyna, Irena; Grabczewski, Zbigniew

    1995-03-01

    To cut inlay from a stack of glued veneer a CO2 HEBAR-1A laser was used. For setting optimal working parameters of the set used in industrial production of inlay the following elements were defined: the shape and dimensions of the cutting fissure, the dependence between the width of the cutting fissure and the speed with which the laser beam moves and the total thickness of the stack of veneer sheets, the application of the laser for cutting various patterns. Computer aided designing and computer steering of the laser beam enables fast and precise production of large numbers of inlay elements not only from wood but also from other materials like glass, stone, metal, etc. Taking into consideration the high running cost of such a laser set and its very big production only few factories or even one factory in the given area could produce inlay ready for gluing. Further investigation should be carried out on this field particularly considering the lowering of costs not only in inlay production but generally where cutting of wood is concerned.

  6. Study of Sweep and Induced Dihedral Effects in Subsonic Axial Flow Compressor Passages—Part I: Design Considerations—Changes in Incidence, Deflection, and Streamline Curvature

    Directory of Open Access Journals (Sweden)

    P. V. Ramakrishna

    2009-01-01

    Full Text Available This article presents the study of Tip Chordline Sweeping (TCS and Axial Sweeping (AXS of low-speed axial compressor rotor blades against the performance of baseline unswept rotor (UNS for different tip clearance levels. The first part of the paper discusses the changes in design parameters when the blades are swept, while the second part throws light on the effect of sweep on tip leakage flow-related phenomena. 15 domains are studied with 5 sweep configurations (0∘, 20∘ TCS, 30∘ TCS, 20∘ AXS, and 30∘ AXS and for 3 tip clearances (0.0%, 0.7%, and 2.7% of the blade chord. A commercial CFD package is employed for the flow simulations and analysis. Results are well validated with experimental data. Forward sweep reduced the flow incidences. This is true all over the span with axial sweeping while little higher incidences below the mid span are observed with tip chordline sweeping. Sweeping is observed to lessen the flow turning. AXS rotors demonstrated more efficient energy transfer among the rotors. Tip chordline sweep deflected the flow towards the hub while effective positive dihedral induced with axial sweeping resulted in outward deflection of flow streamlines. These deflections are more at lower mass flow rates.

  7. A Primary Study on Using Sweeping Micellar Electrokinetic Chromatography in Experimental Teaching%胶束扫集毛细管电动色谱用于实验教学初探

    Institute of Scientific and Technical Information of China (English)

    李斯光; 肖婉娜; 储炫

    2015-01-01

    Modern vocational education call for teaching integration with learning and practice, but it was difficult to carry out, because of high teaching cost when using high performance liquid chromatography ( HPLC ) whit expensive equipment and too many consumption.As a way to reduce cost, sweeping micellar electrokinetic chromatography (Sweep-MEKC) was proposed to using in chromatographic analysis basic experiment teaching, the cost was cut almost 99%down when compare to HPLC for each experiment, so Sweep-MEKC could provided more training chances for student.The aspects of experiment purposes, method principle, experimental design and experimental data processing were also discussed.%现代职业教育提倡“教学做一体化”的教学模式,针对液相色谱设备昂贵,实验消耗多,教学成本较高等问题,首次提出在色谱分析基础实验教学中应用胶束扫集毛细管电动色谱技术,单次实验成本降低到约为高效液相色谱法的百分之一,大大提高实验经费使用效率,增加学生实践机会。并从方法原理、实验目的、实验方法设计、数据记录及处理等方面开展实例探讨。

  8. Equilibrium Analysis in Cake Cutting

    DEFF Research Database (Denmark)

    Branzei, Simina; Miltersen, Peter Bro

    2013-01-01

    Cake cutting is a fundamental model in fair division; it represents the problem of fairly allocating a heterogeneous divisible good among agents with different preferences. The central criteria of fairness are proportionality and envy-freeness, and many of the existing protocols are designed...... to guarantee proportional or envy-free allocations, when the participating agents follow the protocol. However, typically, all agents following the protocol is not guaranteed to result in a Nash equilibrium. In this paper, we initiate the study of equilibria of classical cake cutting protocols. We consider one...... of the simplest and most elegant continuous algorithms -- the Dubins-Spanier procedure, which guarantees a proportional allocation of the cake -- and study its equilibria when the agents use simple threshold strategies. We show that given a cake cutting instance with strictly positive value density functions...

  9. Application of water jetfor cutting polymer materials

    Directory of Open Access Journals (Sweden)

    A. Stoić

    2013-04-01

    Full Text Available Due to the nature of polymeric materials, during thermal cutting processes it leads to their melting, and therefore appear errors in the final product. This paper presents a “cold” process of cutting polyamide 6 ie. SIPAS 60, where there are given the characteristics of materials and guidelines for satisfactory quality of process. The authors made the cut experiment 32 were they changed the cutting parameters (cutting pressure, cutting feed and abrasive mass flow; the surface roughness was measured by the depth of material, because the roughness changes with the thickness of the material to be cut.

  10. Cutting temperature measurement and material machinability

    Directory of Open Access Journals (Sweden)

    Nedić Bogdan P.

    2014-01-01

    Full Text Available Cutting temperature is very important parameter of cutting process. Around 90% of heat generated during cutting process is then away by sawdust, and the rest is transferred to the tool and workpiece. In this research cutting temperature was measured with artificial thermocouples and question of investigation of metal machinability from aspect of cutting temperature was analyzed. For investigation of material machinability during turning artificial thermocouple was placed just below the cutting top of insert, and for drilling thermocouples were placed through screw holes on the face surface. In this way was obtained simple, reliable, economic and accurate method for investigation of cutting machinability.

  11. Cutting Characteristics of Force Controllable Milling Head

    Institute of Scientific and Technical Information of China (English)

    Shirakashi; Takahiro; Shibuya; Wataru

    2002-01-01

    In order to control cutting force and its direction i n milling operation, a new milling head was developed. The head has two milling cutters, which are connected by a pair of gears and rotate in opposite direction respectively. Both up-cut and down-cut can be carried out simultaneously by t hese milling cutters. The each depth of cut, the ratio of up/down cutting depth , by these cutters can be also selected. The cutting force characteristics were experimentally discussed by changing the ratio. The cut...

  12. The Cutting Process, Chips and Cutting Forces in Machining CFRP

    DEFF Research Database (Denmark)

    Koplev, A.; Lystrup, Aage; Vorm, T.

    1983-01-01

    The cutting of unidirectional CFRP, perpendicular as well as parallel to the fibre orientation, is examined. Shaping experiments, ‘quick-stop’ experiments, and a new chip preparation technique are used for the investigation. The formation of the chips, and the quality of the machined surface...

  13. Correlation methods in cutting arcs

    Energy Technology Data Exchange (ETDEWEB)

    Prevosto, L; Kelly, H, E-mail: prevosto@waycom.com.ar [Grupo de Descargas Electricas, Departamento Ing. Electromecanica, Universidad Tecnologica Nacional, Regional Venado Tuerto, Laprida 651, Venado Tuerto (2600), Santa Fe (Argentina)

    2011-05-01

    The present work applies similarity theory to the plasma emanating from transferred arc, gas-vortex stabilized plasma cutting torches, to analyze the existing correlation between the arc temperature and the physical parameters of such torches. It has been found that the enthalpy number significantly influence the temperature of the electric arc. The obtained correlation shows an average deviation of 3% from the temperature data points. Such correlation can be used, for instance, to predict changes in the peak value of the arc temperature at the nozzle exit of a geometrically similar cutting torch due to changes in its operation parameters.

  14. Microbiopsy/precision cutting devices

    Science.gov (United States)

    Krulevitch, Peter A.; Lee, Abraham P.; Northrup, M. Allen; Benett, William J.

    1999-01-01

    Devices for performing tissue biopsy on a small scale (microbiopsy). By reducing the size of the biopsy tool and removing only a small amount of tissue or other material in a minimally invasive manner, the risks, costs, injury and patient discomfort associated with traditional biopsy procedures can be reduced. By using micromachining and precision machining capabilities, it is possible to fabricate small biopsy/cutting devices from silicon. These devices can be used in one of four ways 1) intravascularly, 2) extravascularly, 3) by vessel puncture, and 4) externally. Additionally, the devices may be used in precision surgical cutting.

  15. Laser Timing Jitter Measurements using a Dual-Sweep Streak Camera at the A0 Photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Ruan, J.; Lumpkin, A.H.; Santucci, J.K.; /Fermilab

    2009-04-30

    Excellent phase stability of the drive laser is a critical performance specification of photoinjectors such as Fermilab's A0 photoinjector (A0PI). Previous efforts based on the measurement of the power spectrum of the signal of a fast photodiode illuminated by the mode locked infrared laser pulse component indicated a phase jitter of less than 1.4 ps (technique limited). A recently procured dual sweep plugin unit and existing Hamamatsu C5680 streak camera were used to study the phase stability of the UV laser pulse component. Initial measurements with the synchroscan vertical sweep unit locked to 81.25 MHz showed that the phase slew through the micropulse train and the phase jitter micropulse to micropulse were two key aspects that could be evaluated. The phase slew was much less than 100 fs per micropulse, and the total phase jitter (camera, trigger, and laser) was approximately 300 fs RMS for measurements of 50-micropulse trains. Data on the macropulse phase stability were also obtained. A possible upgrade to achieve better phase stability will be also discussed.

  16. A selective sweep on a deleterious mutation in CPT1A in Arctic populations

    KAUST Repository

    Clemente, Florian J.

    2014-11-01

    Arctic populations live in an environment characterized by extreme cold and the absence of plant foods for much of the year and are likely to have undergone genetic adaptations to these environmental conditions in the time they have been living there. Genome-wide selection scans based on genotype data from native Siberians have previously highlighted a 3 Mb chromosome 11 region containing 79 protein-coding genes as the strongest candidates for positive selection in Northeast Siberians. However, it was not possible to determine which of the genes might be driving the selection signal. Here, using whole-genome high-coverage sequence data, we identified the most likely causative variant as a nonsynonymous G>A transition (rs80356779; c.1436C>T [p.Pro479Leu] on the reverse strand) in CPT1A, a key regulator of mitochondrial long-chain fatty-acid oxidation. Remarkably, the derived allele is associated with hypoketotic hypoglycemia and high infant mortality yet occurs at high frequency in Canadian and Greenland Inuits and was also found at 68% frequency in our Northeast Siberian sample. We provide evidence of one of the strongest selective sweeps reported in humans; this sweep has driven this variant to high frequency in circum-Arctic populations within the last 6-23 ka despite associated deleterious consequences, possibly as a result of the selective advantage it originally provided to either a high-fat diet or a cold environment.

  17. Mutagenic activity of sweepings and pigments from a household-wax factory assayed with Salmonella typhimurium.

    Science.gov (United States)

    Varella, S D; Pozetti, G L; Vilegas, W; Varanda, E A

    2004-12-01

    The mutagenic activity of garbage originating from a household wax industry was determined by the Salmonella/microsome assay, using the bacterial strains TA100, TA98 and YG1024. The garbage was obtained by sweeping the floor of the factory at the end of the work shift. Organic compounds were extracted by ultrasound for 30 min in dichloromethane or 70% ethanol. After evaporation of solvent, these extracts (HFS: household-wax factory sweepings) were dissolved in DMSO, and were tested for the mutagenic activity at varying concentrations (HFS-ET: 0.08-0.68 mg/plate, HFS-DCM: 0.60-7.31 mg/plate). The colouring agents (pigments) used in the production of the wax were also dissolved in DMSO and tested with the assay. The concentrations tested for each pigment were: Amaranth: 0.46-3.65 mg/plate, Auramine: 0.15-1.2 mg/plate and Rhodamine B: 0.22-1.82 mg/plate. Both ET and DCM organic extracts had mutagenic activity, especially in the YG1024 strain. The pigments behaved in a similar way, demonstrating that YG1024 was the most sensitive strain for the detection of mutagenicity, and that metabolization increased the activity. Human exposure (occupational and non-occupational) to industrial residues generated during the household-wax manufacturing and packaging process should be monitored, since this type of garbage is normally deposited in the environment without any control.

  18. Selection Under Domestication: Evidence for a Sweep in the Rice Waxy Genomic Region

    Science.gov (United States)

    Olsen, Kenneth M.; Caicedo, Ana L.; Polato, Nicholas; McClung, Anna; McCouch, Susan; Purugganan, Michael D.

    2006-01-01

    Rice (Oryza sativa) was cultivated by Asian Neolithic farmers >11,000 years ago, and different cultures have selected for divergent starch qualities in the rice grain during and after the domestication process. An intron 1 splice donor site mutation of the Waxy gene is responsible for the absence of amylose in glutinous rice varieties. This mutation appears to have also played an important role in the origin of low amylose, nonglutinous temperate japonica rice varieties, which form a primary component of Northeast Asian cuisines. Waxy DNA sequence analyses indicate that the splice donor mutation is prevalent in temperate japonica rice varieties, but rare or absent in tropical japonica, indica, aus, and aromatic varieties. Sequence analysis across a 500-kb genomic region centered on Waxy reveals patterns consistent with a selective sweep in the temperate japonicas associated with the mutation. The size of the selective sweep (>250 kb) indicates very strong selection in this region, with an inferred selection coefficient that is higher than similar estimates from maize domestication genes or wild species. These findings demonstrate that selection pressures associated with crop domestication regimes can exceed by one to two orders of magnitude those observed for genes under even strong selection in natural systems. PMID:16547098

  19. Analytic curve frequency-sweeping stability tests for systems with commensurate delays

    CERN Document Server

    Li, Xu-Guang; Cela, Arben

    2015-01-01

    In this brief the authors establish a new frequency-sweeping framework to solve the complete stability problem for time-delay systems with commensurate delays. The text describes an analytic curve perspective which allows a deeper understanding of spectral properties focusing on the asymptotic behavior of the characteristic roots located on the imaginary axis as well as on properties invariant with respect to the delay parameters. This asymptotic behavior is shown to be related by another novel concept, the dual Puiseux series which helps make frequency-sweeping curves useful in the study of general time-delay systems. The comparison of Puiseux and dual Puiseux series leads to three important results: an explicit function of the number of unstable roots simplifying analysis and design of time-delay systems so that to some degree they may be dealt with as finite-dimensional systems; categorization of all time-delay systems into three types according to their ultimate stability properties; and a simple frequenc...

  20. Theory of linear sweep voltammetry with diffuse charge: Unsupported electrolytes, thin films, and leaky membranes

    Science.gov (United States)

    Yan, David; Bazant, Martin Z.; Biesheuvel, P. M.; Pugh, Mary C.; Dawson, Francis P.

    2017-03-01

    Linear sweep and cyclic voltammetry techniques are important tools for electrochemists and have a variety of applications in engineering. Voltammetry has classically been treated with the Randles-Sevcik equation, which assumes an electroneutral supported electrolyte. In this paper, we provide a comprehensive mathematical theory of voltammetry in electrochemical cells with unsupported electrolytes and for other situations where diffuse charge effects play a role, and present analytical and simulated solutions of the time-dependent Poisson-Nernst-Planck equations with generalized Frumkin-Butler-Volmer boundary conditions for a 1:1 electrolyte and a simple reaction. Using these solutions, we construct theoretical and simulated current-voltage curves for liquid and solid thin films, membranes with fixed background charge, and cells with blocking electrodes. The full range of dimensionless parameters is considered, including the dimensionless Debye screening length (scaled to the electrode separation), Damkohler number (ratio of characteristic diffusion and reaction times), and dimensionless sweep rate (scaled to the thermal voltage per diffusion time). The analysis focuses on the coupling of Faradaic reactions and diffuse charge dynamics, although capacitive charging of the electrical double layers is also studied, for early time transients at reactive electrodes and for nonreactive blocking electrodes. Our work highlights cases where diffuse charge effects are important in the context of voltammetry, and illustrates which regimes can be approximated using simple analytical expressions and which require more careful consideration.

  1. Genome-wide Selective Sweeps in Natural Bacterial Populations Revealed by Time-series Metagenomics

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Leong-Keat; Bendall, Matthew L.; Malfatti, Stephanie; Schwientek, Patrick; Tremblay, Julien; Schackwitz, Wendy; Martin, Joel; Pati, Amrita; Bushnell, Brian; Foster, Brian; Kang, Dongwan; Tringe, Susannah G.; Bertilsson, Stefan; Moran, Mary Ann; Shade, Ashley; Newton, Ryan J.; Stevens, Sarah; McMahon, Katherine D.; Malmstrom, Rex R.

    2014-06-18

    Multiple evolutionary models have been proposed to explain the formation of genetically and ecologically distinct bacterial groups. Time-series metagenomics enables direct observation of evolutionary processes in natural populations, and if applied over a sufficiently long time frame, this approach could capture events such as gene-specific or genome-wide selective sweeps. Direct observations of either process could help resolve how distinct groups form in natural microbial assemblages. Here, from a three-year metagenomic study of a freshwater lake, we explore changes in single nucleotide polymorphism (SNP) frequencies and patterns of gene gain and loss in populations of Chlorobiaceae and Methylophilaceae. SNP analyses revealed substantial genetic heterogeneity within these populations, although the degree of heterogeneity varied considerably among closely related, co-occurring Methylophilaceae populations. SNP allele frequencies, as well as the relative abundance of certain genes, changed dramatically over time in each population. Interestingly, SNP diversity was purged at nearly every genome position in one of the Chlorobiaceae populations over the course of three years, while at the same time multiple genes either swept through or were swept from this population. These patterns were consistent with a genome-wide selective sweep, a process predicted by the ‘ecotype model’ of diversification, but not previously observed in natural populations.

  2. Electromotive Triggering and Single Sweep Analysis of Vestibular Evoked Myogenic Potentials (VEMPs).

    Science.gov (United States)

    Hecker, Dietmar J; Lohscheller, Joerg; Schorn, Bianca; Koch, Klaus Peter; Schick, Bernhard; Dlugaiczyk, Julia

    2014-01-01

    Cervical (c) and ocular (o) vestibular evoked myogenic potentials (VEMPs) provide important tools for measuring otolith function. However, two major drawbacks of this method are encountered in clinical practice. First, recording of oVEMPs is compromised by small n10 amplitudes. Second, VEMP analysis is currently based on the averaging technique, resulting in a loss of information compared to single sweep analysis. Here, we: 1) developed a novel electromotive trigger mechanism for evoking VEMPs by bone-conducted vibration to the forehead and 2) established maximum entropy extraction of complex wavelet transforms for calculation of phase synchronization between VEMP single sweeps. Both c- and oVEMPs were recorded for n=10 healthy individuals. The oVEMP n10 amplitude was consistently higher (right: 24.84±9.71 μV; left: 27.40±14.55 μV) than previously described. Stable VEMP signals were reached after a smaller number of head taps (oVEMPs 6; cVEMPs 11) compared to current recommendations. Phase synchronization vectors and phase shift values were successfully determined for simulated and clinically recorded VEMPs, providing information about the impact of noise and phase jitter on the VEMP signal. Thus, the proposed method constitutes an easy-to-use approach for the fast detection and analysis of VEMPs in clinical practice.

  3. Rapidly fluctuating environments constrain coevolutionary arms races by impeding selective sweeps.

    Science.gov (United States)

    Harrison, Ellie; Laine, Anna-Liisa; Hietala, Mikael; Brockhurst, Michael A

    2013-08-07

    Although pervasive, the impact of temporal environmental heterogeneity on coevolutionary processes is poorly understood. Productivity is a key temporally heterogeneous variable, and increasing productivity has been shown to increase rates of antagonistic arms race coevolution, and lead to the evolution of more broadly resistant hosts and more broadly infectious parasites. We investigated the effects of the grain of environmental heterogeneity, in terms of fluctuations in productivity, on bacteria-phage coevolution. Our findings demonstrate that environmental heterogeneity could constrain antagonistic coevolution, but that its effect was dependent upon the grain of heterogeneity, such that both the rate and extent of coevolution were most strongly limited in fine-grained, rapidly fluctuating heterogeneous environments. We further demonstrate that rapid environmental fluctuations were likely to have impeded selective sweeps of resistance alleles, which occurred over longer durations than the fastest, but not the slowest, frequency of fluctuations used. Taken together our results suggest that fine-grained environmental heterogeneity constrained the coevolutionary arms race by impeding selective sweeps.

  4. Evidence for selective sweeps by Wolbachia infections: phylogeny of Altica leaf beetles and their reproductive parasites.

    Science.gov (United States)

    Jäckel, Regina; Mora, Diana; Dobler, Susanne

    2013-08-01

    Infections with maternally inherited Wolbachia bacteria may have dramatic influences on reproductive traits and speciation patterns of their hosts. We here show that in the beetle genus Altica, infection has influenced phylogenetic patterns of the host's mtDNA and different strains led to repeated selective sweeps. By comparing a COI/II-based phylogeny of the hosts with a phylogeny of the bacteria based on ftsZ, we show that cospeciation is rare and restricted to few recently diverged species. While in general each species apparently harbours a single Wolbachia strain, Altica lythri presents a strikingly different pattern: in the polyphyletic species, three highly divergent mtDNA haplotypes (2.1-4.6% p-distance) are coupled with three different Wolbachia strains (wLytA1, wLytA2 and wLytB). These haplotypes and Wolbachia strains are widely distributed and mostly found in sympatry. A phylogeny based on microsatellite data supports the monophyly of A. lythri. The discrepancy between mtDNA and nuclear phylogeny may best be explained by interspecific hybridization that led to introgression of mtDNA coupled with a different Wolbachia strain. Selective sweeps apparently drove the introgressed haplotypes to widespread distribution. As for effects of Wolbachia on reproduction, infection with wLytA1 appears to be correlated with a substantial sex ratio distortion, which was most prominent in A. lythri.

  5. Cross-polarization phenomena in the NMR of fast spinning solids subject to adiabatic sweeps.

    Science.gov (United States)

    Wi, Sungsool; Gan, Zhehong; Schurko, Robert; Frydman, Lucio

    2015-02-14

    Cross-polarization magic-angle spinning (CPMAS) experiments employing frequency-swept pulses are explored within the context of obtaining broadband signal enhancements for rare spin S = 1/2 nuclei at very high magnetic fields. These experiments employ adiabatic inversion pulses on the S-channel ((13)C) to cover a wide frequency offset range, while simultaneously applying conventional spin-locking pulse on the I-channel ((1)H). Conditions are explored where the adiabatic frequency sweep width, Δν, is changed from selectively irradiating a single magic-angle-spinning (MAS) spinning centerband or sideband, to sweeping over multiple sidebands. A number of new physical features emerge upon assessing the swept-CP method under these conditions, including multiple zero- and double-quantum CP transfers happening in unison with MAS-driven rotary resonance phenomena. These were examined using an average Hamiltonian theory specifically designed to tackle these experiments, with extensive numerical simulations, and with experiments on model compounds. Ultrawide CP profiles spanning frequency ranges of nearly 6⋅γB1 (s) were predicted and observed utilizing this new approach. Potential extensions and applications of this extremely broadband transfer conditions are briefly discussed.

  6. Experiments and error analysis of laser ranging based on frequency-sweep polarization modulation

    Science.gov (United States)

    Gao, Shuyuan; Ji, Rongyi; Li, Yao; Cheng, Zhi; Zhou, Weihu

    2016-11-01

    Frequency-sweep polarization modulation ranging uses a polarization-modulated laser beam to determine the distance to the target, the modulation frequency is swept and frequency values are measured when transmitted and received signals are in phase, thus the distance can be calculated through these values. This method gets much higher theoretical measuring accuracy than phase difference method because of the prevention of phase measurement. However, actual accuracy of the system is limited since additional phase retardation occurs in the measuring optical path when optical elements are imperfectly processed and installed. In this paper, working principle of frequency sweep polarization modulation ranging method is analyzed, transmission model of polarization state in light path is built based on the theory of Jones Matrix, additional phase retardation of λ/4 wave plate and PBS, their impact on measuring performance is analyzed. Theoretical results show that wave plate's azimuth error dominates the limitation of ranging accuracy. According to the system design index, element tolerance and error correcting method of system is proposed, ranging system is built and ranging experiment is performed. Experiential results show that with proposed tolerance, the system can satisfy the accuracy requirement. The present work has a guide value for further research about system design and error distribution.

  7. Effects of Fin Leading Edge Sweep on Shock-Shock Interaction at Mach 6

    Science.gov (United States)

    Berry, Scott A.; Nowak, Robert J.

    1996-01-01

    The effects of fin leading edge sweep on peak heating rates due to shock-shock interaction have been experimentally examined in the Langley 20-Inch Mach 6 Tunnel. The shock interaction was produced by the intersection of a planar incident shock (16.8 deg shock angle relative to the freestream, generated by a 9 deg wedge) with the bow shock formed around a O.5-inch diameter cylindrical leading edge fin. Heating distributions along the leading edge stagnation line have been obtained using densely spaced thin film resistive-type sensors. Schlieren images were obtained to illustrate the very complex shock-shock interactions. The fin leading edge sweep angle was varied from 15-degrees swept back to 45-degrees swept forward for a freestream unit Reynolds number of 2 x 10(exp 6)/ft. Two models were utilized during the study, one with 0.025-inch spacing between gage centers, and the other 0.015-inch spacing. Gage spatial resolution on the order of 0.015-in appeared to accurately capture the narrow spike in heating. Peak heating due to shock interaction was maximized when the fin was swept forward 15 deg and 25 deg, both promoting augmentations about 7 times the baseline value. The schlieren images for these cases revealed Type 4 and Type 3 interactions, respectively.

  8. Genome-wide Selective Sweeps in Natural Bacterial Populations Revealed by Time-series Metagenomics

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Leong-Keat; Bendall, Matthew L.; Malfatti, Stephanie; Schwientek, Patrick; Tremblay, Julien; Schackwitz, Wendy; Martin, Joel; Pati, Amrita; Bushnell, Brian; Foster, Brian; Kang, Dongwan; Tringe, Susannah G.; Bertilsson, Stefan; Moran, Mary Ann; Shade, Ashley; Newton, Ryan J.; Stevens, Sarah; McMcahon, Katherine D.; Mamlstrom, Rex R.

    2014-05-12

    Multiple evolutionary models have been proposed to explain the formation of genetically and ecologically distinct bacterial groups. Time-series metagenomics enables direct observation of evolutionary processes in natural populations, and if applied over a sufficiently long time frame, this approach could capture events such as gene-specific or genome-wide selective sweeps. Direct observations of either process could help resolve how distinct groups form in natural microbial assemblages. Here, from a three-year metagenomic study of a freshwater lake, we explore changes in single nucleotide polymorphism (SNP) frequencies and patterns of gene gain and loss in populations of Chlorobiaceae and Methylophilaceae. SNP analyses revealed substantial genetic heterogeneity within these populations, although the degree of heterogeneity varied considerably among closely related, co-occurring Methylophilaceae populations. SNP allele frequencies, as well as the relative abundance of certain genes, changed dramatically over time in each population. Interestingly, SNP diversity was purged at nearly every genome position in one of the Chlorobiaceae populations over the course of three years, while at the same time multiple genes either swept through or were swept from this population. These patterns were consistent with a genome-wide selective sweep, a process predicted by the ecotype model? of diversification, but not previously observed in natural populations.

  9. Linear sweep polarographic determination of nucleic acids using acridine orange as a bioprobe

    Directory of Open Access Journals (Sweden)

    WEI SUN

    2007-11-01

    Full Text Available The interaction of acridine orange (AO with double-stranded (ds DNA in aqueous solution was investigated by linear sweep polarography (LSP on a dropping mercury working electrode (DME. In pH 2.5 Britton–Robinson (B–R buffer solution, AO had a sensitive linear sweep polarographic reductive peak at –0.89 V (vs. SCE, which could be greatly inhibited by the addition of dsDNA, with a positive shift of the peak potential. Based on the decrease of the reductive peak current, a new quantitative electrochemical determination method for dsDNA was developed with a linear range of 2.0−20.0 mg l-1 and the linear regression equation: ΔIp” (nA = 111.90 C (mg l-1+125.32 (n = 9, γ = 0.997. The influences of commonly co-existing substances, such as metal ions, amino acid, etc., on the determination were also investigated. The method is sensitive, rapid and simple with good selectivity. The new proposed method was further applied to the detection of RNA and three synthetic samples containing dsDNA with satisfactory results. The binding number and the equilibrium constant between dsDNA and AO were calculated by an electrochemical method.

  10. Femtosecond Laser Tagging Characterization of a Sweeping Jet Actuator Operating in the Compressible Regime

    Science.gov (United States)

    Peters, Christopher J.; Miles, Richard B.; Burns, Ross A.; Bathel, Brett F.; Jones, Gregory S.; Danehy, Paul M.

    2016-01-01

    A sweeping jet (SWJ) actuator operating over a range of nozzle pressure ratios (NPRs) was characterized with femtosecond laser electronic excitation tagging (FLEET), single hot-wire anemometry (HWA) and high-speed/phase-averaged schlieren. FLEET velocimetry was successfully demonstrated in a highly unsteady, oscillatory flow containing subsonic through supersonic velocities. Qualitative comparisons between FLEET and HWA (which measured mass flux since the flow was compressible) showed relatively good agreement in the external flow profiles. The spreading rate was found to vary from 0.5 to 1.2 depending on the pressure ratio. The precision of FLEET velocity measurements in the external flow field was poorer (is approximately equal to 25 m/s) than reported in a previous study due to the use of relatively low laser fluences, impacting the velocity fluctuation measurements. FLEET enabled velocity measurements inside the device and showed that choking likely occurred for NPR = 2.0, and no internal shockwaves were present. Qualitative oxygen concentration measurements using FLEET were explored in an effort to gauge the jet's mixing with the ambient. The jet was shown to mix well within roughly four throat diameters and mix fully within roughly eight throat diameters. Schlieren provided visualization of the internal and external flow fields and showed that the qualitative structure of the internal flow does not vary with pressure ratio and the sweeping mechanism observed for incompressible NPRs also probably holds for compressible NPRs.

  11. The Effect of Leading-Edge Sweep and Surface Inclination on the Hypersonic Flow Field Over a Blunt Flat Plate

    Science.gov (United States)

    Creager, Marcus O.

    1959-01-01

    An investigation of the effects of variation of leading-edge sweep and surface inclination on the flow over blunt flat plates was conducted at Mach numbers of 4 and 5.7 at free-stream Reynolds numbers per inch of 6,600 and 20,000, respectively. Surface pressures were measured on a flat plate blunted by a semicylindrical leading edge over a range of sweep angles from 0 deg to 60 deg and a range of surface inclinations from -10 deg to +10 deg. The surface pressures were predicted within an average error of +/- 8 percent by a combination of blast-wave and boundary-layer theory extended herein to include effects of sweep and surface inclination. This combination applied equally well to similar data of other investigations. The local Reynolds number per inch was found to be lower than the free-stream Reynolds number per inch. The reduction in local Reynolds number was mitigated by increasing the sweep of the leading edge. Boundary-layer thickness and shock-wave shape were changed little by the sweep of the leading edge.

  12. Wedge cutting of mild steel by CO 2 laser and cut-quality assessment in relation to normal cutting

    Science.gov (United States)

    Yilbas, B. S.; Karatas, C.; Uslan, I.; Keles, O.; Usta, Y.; Yilbas, Z.; Ahsan, M.

    2008-10-01

    In some applications, laser cutting of wedge surfaces cannot be avoided in sheet metal processing and the quality of the end product defines the applicability of the laser-cutting process in such situations. In the present study, CO 2 laser cutting of the wedge surfaces as well as normal surfaces (normal to laser beam axis) is considered and the end product quality is assessed using the international standards for thermal cutting. The cut surfaces are examined by the optical microscopy and geometric features of the cut edges such as out of flatness and dross height are measured from the micrographs. A neural network is introduced to classify the striation patterns of the cut surfaces. It is found that the dross height and out of flatness are influenced significantly by the laser output power, particularly for wedge-cutting situation. Moreover, the cut quality improves at certain value of the laser power intensity.

  13. Analysis of changes in paper cutting forces during the cutting cycle in single-knife guillotine

    OpenAIRE

    Rusin, Agnieszka; Petriaszwili, Georgij

    2013-01-01

    Paper presents the results of changes in the three components of cutting forces of paper stacks cutting during the cutting cycle in single-knife guillotine. The changes of the three components of cutting force at different stages of cutting cycle were analyzed.

  14. How Can I Stop Cutting?

    Science.gov (United States)

    ... have razors near the tub) listen to soothing music that will shift your mood try a breathing exercise try some relaxing yoga exercises previous continue Things to Help You Express the Pain and Deep Emotion Some people cut because the emotions that they ...

  15. How Can I Stop Cutting?

    Science.gov (United States)

    ... previous continue Things to Help You Express the Pain and Deep Emotion Some people cut because the emotions that they ... may be hard for them to recognize these emotions for what they are — like anger, ... out your hurt, anger, or pain using a pen and paper draw the pain ...

  16. Why I like power cuts...

    CERN Multimedia

    Computer Security Team

    2012-01-01

    Accidental power cuts - a permanent nuisance when running accelerators or computing services, since it takes a lot of time to recover from them. While I feel very sorry for those who are under pressure to get their service running again and deeply regret the loss of down-time and availability, I must admit that I like power cuts: power cuts make computers reboot! And rebooting computers at CERN means all the pending software patches are automatically applied.   But don’t think I am egotistic enough to endorse power cuts. Not necessarily! I am already happy if you regularly patch your computer(s) yourself, where regularly means at least once a month: · If you run a centrally or locally managed Windows computer, give that small orange blinking “CMF” icon in the taskbar a chance in the evening to apply all the pending patches. Also, let it initiate a reboot at the end! · If you have a personal computer with your own Windows operating system, ...

  17. Quality Analysis of Cutting Steel Using Laser

    Directory of Open Access Journals (Sweden)

    Vladislav Markovič

    2013-02-01

    Full Text Available The article explores the quality dependence of the edge surface of steel C45 LST EN 10083-1 obtained cutting the material using laser on different cutting regimes and variations in the thickness of trial steel. The paper presents the influence of the main modes of laser cutting equipment Trulaser 3030, including cutting speed, pressure, angle and the thickness of the surface on the quality characteristics of the sample. The quality of the edge after laser cutting is the most important indicator influencing such technological spread in industry worldwide. Laser cutting is the most popular method of material cutting. Therefore, the article focuses on cutting equipment, cutting defects and methods of analysis. Research on microstructure, roughness and micro-toughness has been performed with reference to edge samples. At the end of the publication, conclusions are drawn.Article in Lithuanian

  18. Quality Analysis of Cutting Steel Using Laser

    Directory of Open Access Journals (Sweden)

    Vladislav Markovič

    2012-12-01

    Full Text Available The article explores the quality dependence of the edge surface of steel C45 LST EN 10083-1 obtained cutting the material using laser on different cutting regimes and variations in the thickness of trial steel. The paper presents the influence of the main modes of laser cutting equipment Trulaser 3030, including cutting speed, pressure, angle and the thickness of the surface on the quality characteristics of the sample. The quality of the edge after laser cutting is the most important indicator influencing such technological spread in industry worldwide. Laser cutting is the most popular method of material cutting. Therefore, the article focuses on cutting equipment, cutting defects and methods of analysis. Research on microstructure, roughness and micro-toughness has been performed with reference to edge samples. At the end of the publication, conclusions are drawn.Article in Lithuanian

  19. Fibre laser cutting stainless steel: Fluid dynamics and cut front morphology

    Science.gov (United States)

    Pocorni, Jetro; Powell, John; Deichsel, Eckard; Frostevarg, Jan; Kaplan, Alexander F. H.

    2017-01-01

    In this paper the morphology of the laser cut front generated by fibre lasers was investigated by observation of the 'frozen' cut front, additionally high speed imaging (HSI) was employed to study the fluid dynamics on the cut front while cutting. During laser cutting the morphology and flow properties of the melt film on the cut front affect cut quality parameters such as cut edge roughness and dross (residual melt attached to the bottom of the cut edge). HSI observation of melt flow down a laser cutting front using standard cutting parameters is experimentally problematic because the cut front is narrow and surrounded by the kerf walls. To compensate for this, artificial parameters are usually chosen to obtain wide cut fronts which are unrepresentative of the actual industrial process. This paper presents a new experimental cutting geometry which permits HSI of the laser cut front using standard, commercial parameters. These results suggest that the cut front produced when cutting medium section (10 mm thick) stainless steel with a fibre laser and a nitrogen assist gas is covered in humps which themselves are covered by a thin layer of liquid. HSI observation and theoretical analysis reveal that under these conditions the humps move down the cut front at an average speed of approximately 0.4 m/s while the covering liquid flows at an average speed of approximately 1.1 m/s, with an average melt depth at the bottom of the cut zone of approximately 0.17 mm.

  20. Cationic gemini pyrrolidinium surfactants based sweeping-micellar electrokinetic chromatography for simultaneous detection of nine organic pollutants in environmental water.

    Science.gov (United States)

    Tian, Yu; Wei, Ran; Cai, Bo; Dong, Jinfeng; Deng, Bin; Xiao, Yuxiu

    2016-12-02

    A series of novel cationic gemini surfactants with pyrrolidinium head groups, 1,1'-(butane-1,s-alkyl) bis (1-alkylpyrrolidinium) (Cn-4-CnPB, n=12, 14, 16), were employed as carriers in sweeping-micellar electrokinetic chromatography (sweeping-MEKC) for simultaneous detection of nine organic water pollutants, including polycyclic aromatic hydrocarbons, sulfonamides and steroids. The sweeping and separation conditions were optimized. Cn-4-CnPB (n=12, 14, 16) were compared with cetyltrimethylammonium bromide (CTAB) in terms of their abilities to preconcentrate and separate the nine analytes. Under the optimized conditions, the sensitivity enhancement factors based on the peak height (SEFsHeight) were ca. 310-580 of C16-4-C16PB, which were higher than those of C14-4-C14PB (120-290) and C12-4-C12PB (110-160). Meanwhile, the SEFsHeight of C16-4-C16PB were higher than those of 30% (v/v) methanol-modified CTAB (140-320). The C16-4-C16PB based sweeping-MEKC, coupled with offline solid phase extraction and UV detection (228nm), was used to analyze spiked environmental water samples. The nine analytes were successfully separated and detected. The limit of detection (S/N=3) was in range of 2.79-3.76ng/mL, and the recovery ranged from 70.8% to 95.5% with the RSDs less than 9.89%. This study confirms that the C16-4-C16PB based sweeping-MEKC has significant advantages over the CTAB based sweeping-MEKC and it is a promising method for sensitive and simultaneous detection of polycyclic aromatic hydrocarbons, sulfonamides and steroids in environmental water samples.

  1. Determination of ephedrine and codeine in human urine by cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography

    Institute of Scientific and Technical Information of China (English)

    Li Jun Li; Si Guang Li; Hai Yan Li; Zhuo Cai; Hao Cheng

    2009-01-01

    A sensitive method for the determination of ephedrine and codeine in human urine by capillary electrophoresis (CE) was described. In order to improve the sensitivity, two online concentration techniques including cation-selective exhaustive injection (CSEI) and sweeping micellar electrokinetic chromatography (sweeping-MEKC) were used. Under the optimum conditions, the detection limits (S/N = 3) were 0.10 μg/L for ephedrine and 0.80 μg/L for codeine. This method was successfully applied to real urine sample analysis.

  2. Broad-range self-sweeping of a narrow-line self-pulsing Yb-doped fiber laser

    Science.gov (United States)

    Lobach, Ivan A.; Kablukov, Sergey I.; Podivilov, Evgeniy V.; Babin, Sergey A.

    2011-08-01

    The effect of broad-range (16 nm) self-sweeping of a narrow-line (less than 1 pm) Yb-doped fiber laser has been demonstrated experimentally. It is found that the effect arises from the self-sustained relaxation oscillations. As a result, the sweeping rate increases as square root of the laser power and decreases with increasing cavity length. Based on these results we propose a model describing dynamics of the laser frequency. The model takes into account the effects of gain saturation at the laser transition and spatial hole burning in the self-pulsing regime.

  3. Laser Cutting of Thin Nickel Bellows

    Science.gov (United States)

    Butler, C. L.

    1986-01-01

    Laser cutting technique produces narrow, precise, fast, and repeatable cuts in thin nickel-allow bellows material. Laser cutting operation uses intense focused beam to melt material and assisting gas to force melted material through part thickness, creating void. When part rotated or moved longitudinally, melting and material removal continuous and creates narrow, fast, precise, and repeatable cut. Technique used to produce cuts of specified depths less than material thickness. Avoids distortion, dents, and nicks produced in delicate materials during lathe trimming operations, which require high cutting-tool pressure and holding-fixture forces.

  4. Cutting

    Science.gov (United States)

    ... way some people try to cope with the pain of strong emotions, intense pressure , or upsetting relationship problems . They may ... with difficulties, even big problems and terrible emotional pain. The help of ... or overwhelming emotions. For other tough situations or strong emotions, it ...

  5. Effect of cutting parameters on chip formation in orthogonal cutting

    Directory of Open Access Journals (Sweden)

    S. Ben Salem

    2012-01-01

    Full Text Available Purpose: of this paper is to study the chip formation to obtain the optimal cutting conditions and to observe the different chip formation mechanisms. Analysis of machining of a hardened alloy, X160CrMoV12-1 (cold work steel: AISI D2 with a ferritic and cementite matrix and coarse primary carbides, showed that there are relationships between the chip geometry, cutting conditions and the different micrographs under different metallurgical states.Design/methodology/approach: Machining of hardened alloys has some metallurgical and mechanical difficulties even if many successful processes have been increasingly developed. A lot of study has been carried out on this subject, however only with modest progress showing specific results concerning the real efficiency of chip formation. Hence, some crucial questions remain unanswered: the evolution of white layers produced during progressive tool flank wear in dry hard turning and to correlate this with the surface integrity of the machined surface. For the experimental study here, various cutting speeds and feed rates have been applied on the work material.Findings: The “saw-tooth type chips” geometry has been examined and a specific attention was given to the chip samples that were metallographically processed and observed under scanning electronic microscope (SEM to determine if white layers are present.Research limitations/implications: This research will be followed by a detail modelling and need more experimental results for a given a good prediction of the results occurred on the damage related to the microstructure by using the cutting parameters.Practical implications: A special detail was given to the mechanism of chip formation resulting from hard machining process and behaviour of steel at different metallurgical states on the material during the case of annealing and or the case of quench operations.Originality/value: For the sake of simplicity, ANOVA (Analysis of Variance was used to

  6. DEVELOPMENT OF POLYMER GEL SYSTEMS TO IMPROVE VOLUMETRIC SWEEP AND REDUCE PRODUCING WATER/OIL RATIOS

    Energy Technology Data Exchange (ETDEWEB)

    G. Paul Willhite; Don W. Green; Stan McCool; Min Cheng; Feiyan Chen

    2004-02-01

    The objectives of the research are to improve the effectiveness of polymer gels to increase volumetric sweep efficiency of fluid displacement processes and to reduce water production in production wells. The research is based on experimental data and conceptual and mathematical models developed from interpretation of experimental data. This report describes two types of mathematical models that were developed. One model type simulates the chemical reactions where polymer molecules are crosslinked to form a 3-dimensional network or gel. The model is based on statistical probabilities of reactions and yields molecular weights averages and distributions as functions of conversion. The second model type simulates the transport of chromium acetate, a common polymer crosslinker, through porous dolomite rock and includes the mechanisms of dolomite dissolution and chromium precipitation. The chromium transport model reasonably agreed with experimental data.

  7. Selective sweep on human amylase genes postdates the split with Neanderthals

    Science.gov (United States)

    Inchley, Charlotte E.; Larbey, Cynthia D. A.; Shwan, Nzar A. A.; Pagani, Luca; Saag, Lauri; Antão, Tiago; Jacobs, Guy; Hudjashov, Georgi; Metspalu, Ene; Mitt, Mario; Eichstaedt, Christina A.; Malyarchuk, Boris; Derenko, Miroslava; Wee, Joseph; Abdullah, Syafiq; Ricaut, François-Xavier; Mormina, Maru; Mägi, Reedik; Villems, Richard; Metspalu, Mait; Jones, Martin K.; Armour, John A. L.; Kivisild, Toomas

    2016-01-01

    Humans have more copies of amylase genes than other primates. It is still poorly understood, however, when the copy number expansion occurred and whether its spread was enhanced by selection. Here we assess amylase copy numbers in a global sample of 480 high coverage genomes and find that regions flanking the amylase locus show notable depression of genetic diversity both in African and non-African populations. Analysis of genetic variation in these regions supports the model of an early selective sweep in the human lineage after the split of humans from Neanderthals which led to the fixation of multiple copies of AMY1 in place of a single copy. We find evidence of multiple secondary losses of copy number with the highest frequency (52%) of a deletion of AMY2A and associated low copy number of AMY1 in Northeast Siberian populations whose diet has been low in starch content. PMID:27853181

  8. Unsteady Flow Simulation of a Sweeping Jet Actuator Using a Lattice-Boltzmann Method

    Science.gov (United States)

    Duda, B.; Wessels, M.; Fares, E.; Vatsa, V.

    2016-01-01

    Active flow control technology is increasingly used in aerospace applications to control flow separation and to improve aerodynamic performance. In this paper, PowerFLOW is used to simulate the flow through a sweeping jet actuator at two different pressure ratios. The lower pressure ratio leads to a high subsonic flow, whereas the high pressure ratio produces a choked flow condition. Comparison of numerical results with experimental data is shown, which includes qualitatively good agreement of pressure histories and spectra. PIV measurements are also available but the simulation overestimates mean and fluctuation quantities outside the actuator. If supply pressure is matched at one point inside the mixing chamber a good qualitative agreement is achieved at all other monitor points.

  9. General Existence Results for Third-Order Nonconvex State-Dependent Sweeping Process with Unbounded Perturbations

    Directory of Open Access Journals (Sweden)

    M. Bounkhel

    2012-01-01

    Full Text Available We prove the existence of solutions for third-order nonconvex state-dependent sweeping process with unbounded perturbations of the form: -A(x(3(t∈N(K(t,ẋ(t;  A(ẍ(t+F(t,x(t,ẋ(t,ẍ(t+G(x(t,ẋ(t,ẍ(t      a.e.  [0,T], A(ẍ(t∈K(t,ẋ(t, a.e.    t∈[0,T], x(0=x0,ẋ(0=u0, ẍ(0=υ0, where T>0, K is a nonconvex Lipschitz set-valued mapping, F is an unbounded scalarly upper semicontinuous convex set-valued mapping, and G is an unbounded uniformly continuous nonconvex set-valued mapping in a separable Hilbert space H.

  10. Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

    Science.gov (United States)

    Torrisi, Giuseppe; Mascali, David; Neri, Lorenzo; Leonardi, Ornella; Sorbello, Gino; Celona, Luigi; Castro, Giuseppe; Agnello, Riccardo; Caruso, Antonio; Passarello, Santi; Longhitano, Alberto; Isernia, Tommaso; Gammino, Santo

    2016-02-01

    The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 1011-1013 cm-3 and it needs a probing beam wavelength of the order of few centimetres, comparable to the chamber radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called "frequency sweep" method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.

  11. A parallel sweeping preconditioner for frequency-domain seismic wave propagation

    KAUST Repository

    Poulson, Jack

    2012-09-01

    We present a parallel implementation of Engquist and Ying\\'s sweeping preconditioner, which exploits radiation boundary conditions in order to form an approximate block LDLT factorization of the Helmholtz operator with only O(N4/3) work and an application (and memory) cost of only O(N logN). The approximate factorization is then used as a preconditioner for GMRES, and we show that essentially O(1) iterations are required for convergence, even for the full SEG/EAGE over-thrust model at 30 Hz. In particular, we demonstrate the solution of said problem in a mere 15 minutes on 8192 cores of TACC\\'s Lonestar, which may be the largest-scale 3D heterogeneous Helmholtz calculation to date. Generalizations of our parallel strategy are also briefly discussed for time-harmonic linear elasticity and Maxwell\\'s equations.

  12. Fluid Diversion and Sweep Improvement with Chemical Gels in Oil Recovery Processes

    Energy Technology Data Exchange (ETDEWEB)

    Seright, R.S.; Martin, F.D.

    1991-11-01

    This report describes progress made during the second year of the three-year project, Fluid diversion and Sweep Improvement with Chemical Gels in Oil Recovery Processes.'' The objectives of this project are to identify the mechanisms by which gel treatments divert fluids in reservoirs and to establish where and how gel treatments are best applied. Several different types of gelants are being examined. This research is directed at gel applications in water injection wells, in production wells, and in high-pressure gasfloods. The work examines how the flow properties of gels and gelling agents are influenced by permeability, lithology, and wettability. Other goals include determining the proper placement of gelants, the stability of in-place gels, and the types of gels required for the various oil recovery processes and for different scales of reservoir heterogeneity. 93 refs., 39 figs., 43 tabs.

  13. The simulative calculation and optimum design for FOA, the purge gas sweeping system

    Science.gov (United States)

    Wang, Liquan; Jing, Yukun; Feng, Bing; Li, Fuquan; Xiang, Yong; Han, Wei; Wang, Fang

    2016-01-01

    This paper first studies the structure effect law in order to design a reasonable option in theory for the Final Optics Assembly(FOA)' harmonic converter module, involved in the design of the fluid theory, including the basic equations of fluid motion, the form of fluid motion and fluid movement in the small hole. Optimizing the structure need to be applied to the simulation software, which requires the Fluent simulation principle. Then, combined with theoretical knowledge to design the overall structure of the multiplier module, It will apply the simulation software to optimize structural parameters of the board and use control system to realize it for verifying the law obtained by simulation under various conditions whether consistent with the law in actual work of the sweeping system.

  14. Surfaces Relief Profilometry of Solid Objects by Sweeping of a Laser Line

    Science.gov (United States)

    Salas-Peimbert, Didia P.; Trujillo-Schiaffino, Gerardo; Mendoza-Villegas, Paloma G.; Ojeda-González, Daniel; Almazán-Cuellar, Saúl; Corral-Martínez, Luis F.

    2008-04-01

    This paper describes the development of a laser system for the digitalization and three-dimensional reconstruction of solid objects. The first step consists of applying on the object a linear sweeping of a thin laser line using a laser diode with 635 nm and 5 mW, a motorized stage for linear displacement of 138 mm, and a controller with RS232 interface. The next step consists of capturing and transmitting the image of the deformed line on the object to a computer. For this step was used a monochrome camera CCD, and an image acquisition board. The last step consists of the three-dimensional reconstruction of the solid object. All the corresponding algorithms were implemented using the programming language LabVIEW.

  15. Fast sweep-rate plastic Faraday force magnetometer with simultaneous sample temperature measurement.

    Science.gov (United States)

    Slobinsky, D; Borzi, R A; Mackenzie, A P; Grigera, S A

    2012-12-01

    We present a design for a magnetometer capable of operating at temperatures down to 50 mK and magnetic fields up to 15 T with integrated sample temperature measurement. Our design is based on the concept of a Faraday force magnetometer with a load-sensing variable capacitor. A plastic body allows for fast sweep rates and sample temperature measurement, and the possibility of regulating the initial capacitance simplifies the initial bridge balancing. Under moderate gradient fields of ~1 T/m our prototype performed with a resolution better than 1 × 10(-5) emu. The magnetometer can be operated either in a dc mode, or in an oscillatory mode which allows the determination of the magnetic susceptibility. We present measurements on Dy(2)Ti(2)O(7) and Sr(3)Ru(2)O(7) as an example of its performance.

  16. A Genome-wide Scan for Selective Sweeps in Racing Horses

    Science.gov (United States)

    Moon, Sunjin; Lee, Jin Woo; Shin, Donghyun; Shin, Kwang-Yun; Kim, Jun; Choi, Ik-Young; Kim, Jaemin; Kim, Heebal

    2015-01-01

    Using next-generation sequencing, we conducted a genome-wide scan of selective sweeps associated with selection toward genetic improvement in Thoroughbreds. We investigated potential phenotypic consequence of putative candidate loci by candidate gene association mapping for the finishing time in 240 Thoroughbred horses. We found a significant association with the trait for Ral GApase alpha 2 (RALGAP2) that regulates a variety of cellular processes of signal trafficking. Neighboring genes around RALGAP2 included insulinoma-associated 1 (INSM1), pallid (PLDN), and Ras and Rab interactor 2 (RIN2) genes have similar roles in signal trafficking, suggesting that a co-evolving gene cluster located on the chromosome 22 is under strong artificial selection in racehorses. PMID:26333666

  17. A Genome-wide Scan for Selective Sweeps in Racing Horses

    Directory of Open Access Journals (Sweden)

    Sunjin Moon

    2015-11-01

    Full Text Available Using next-generation sequencing, we conducted a genome-wide scan of selective sweeps associated with selection toward genetic improvement in Thoroughbreds. We investigated potential phenotypic consequence of putative candidate loci by candidate gene association mapping for the finishing time in 240 Thoroughbred horses. We found a significant association with the trait for Ral GApase alpha 2 (RALGAP2 that regulates a variety of cellular processes of signal trafficking. Neighboring genes around RALGAP2 included insulinoma-associated 1 (INSM1, pallid (PLDN, and Ras and Rab interactor 2 (RIN2 genes have similar roles in signal trafficking, suggesting that a co-evolving gene cluster located on the chromosome 22 is under strong artificial selection in racehorses.

  18. A Test of HTS Power Cable in a Sweeping Magnetic Field

    CERN Document Server

    Piekarz, H; Blowers, J; Shiltsev, V

    2012-01-01

    Short sample HTS power cable composed of multiple 344C-2G strands and designed to energize a fast-cycling dipole magnet was exposed to a sweeping magnetic field in the (2-20) T/s rate. The B-field orientation toward the HTS strands wide surface was varied from 0 deg. to 10 deg., in steps of 1 deg.. The test arrangement allowed measurement of the combined hysteresis and eddy current power losses. For the validity of these measurements, the power losses of a short sample cable composed of multiple LTS wire strands were also performed to compare with the known data. The test arrangement of the power cable is described, and the test results are compared with the projections for the eddy and hysteresis power losses using the fine details of the test cable structures.

  19. Planetesimal formation via sweep-up growth at the inner edge of dead zones

    CERN Document Server

    Drazkowska, J; Dullemond, C P

    2013-01-01

    The early stages of planet formation are still not well understood. Coagulation models have revealed numerous obstacles to the dust growth, such as the bouncing, fragmentation and radial drift barriers. We study the interplay between dust coagulation and drift in order to determine the conditions in protoplanetary disk that support the formation of planetesimals. We focus on planetesimal formation via sweep-up and investigate whether it can take place in a realistic protoplanetary disk. We have developed a new numerical model that resolves spatial distribution of dust in the radial and vertical dimension. The model uses representative particles approach to follow the dust evolution in protoplanetary disk. The coagulation and fragmentation of solids is taken into account using Monte Carlo method. A collision model adopting the mass transfer effect, that can occur for different-sized dust aggregate collisions, is implemented. We focus on a protoplanetary disk including a pressure bump caused by a steep decline ...

  20. Effect of leading edge sweep on shock-shock interference at Mach 8

    Science.gov (United States)

    Glass, Christopher E.; Wieting, Allan R.; Holden, Michael S.

    1989-01-01

    These Mach 8 experimental results are applicable to the details of a shock-shock interference that may occur on an engine inlet of a hypersonic vehicle from a swept forebody shock interacting with a swept cowl leading edge bow shock or from a swept splitter plate shock interacting with a swept fuel injection strut bow shock. Peak surface pressure and heat transfer rate on the cylinder were about 10 and 30 times the undisturbed flow stagnation point value, respectively, for the 0 deg sweep test. A comparison of the 15 deg and 30 deg swept results with the 0 deg swept results shows that peak pressure was reduced about 13 percent and 44 percent, respectively, and peak heat transfer rate was reduced about 7 percent and 27 percent, respectively.

  1. Phase lock acquisition for sampled data PLLs using the sweep technique

    Science.gov (United States)

    Aguirre, S.; Brown, D. H.; Hurd, W. J.

    1986-01-01

    Simulation results of the swept-acquisition performance of residual carrier phase-locked loops (PLLs) are reported. The loops investigated are sampled data counterparts of the continuous time type II and III loops currently in use in Deep Space Network receivers. It was found that sweep rates of 0.2 B(sub L)(2) to 0.4 B(sub L)(2) Hz/s can be used, depending on the loop parameters and loop signal-to-noise ratio (SNR), where B(sub L) is the one-sided loop noise bandwidth. Type III loops are shown to be not as reliable as type II loops for acquisition using this technique, especially at low SNRs.

  2. Reducing Side-Sweep Accidents with Vehicle-to-Vehicle Communication

    Directory of Open Access Journals (Sweden)

    Gamini Bulumulle

    2016-12-01

    Full Text Available Side-sweep accidents are one of the major causes of loss of life and property damage on highways. This type of accident is caused by a driver initiating a lane change while another vehicle is blocking the road in the target lane. In this article, we are trying to quantify the degree to which different implementations of vehicle-to-vehicle (V2V communication could reduce the occurrence of such accidents. We present the design of a simulator that takes into account common sources of lack of driver awareness such as blind-spots and lack of attention. Then, we study the impact of both traditional, non-technological communication means such as turning signals as well as unidirectional and bidirectional V2V communications.

  3. Influence of the Magnetic High-speed Steel Cutting Tool on Cutting Capability

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The high-speed steel cutting tool has advantaged i n modern cutting tool for its preferable synthetical performance, especially, in a pplication of complicated cutting tools. Therefore, the study of the high-speed steel cutting tools that occupied half of cutting tools has become an importa nt way of studying on modern cutting technology. The cutting performance of hi gh speed-steel cutting tools will be improved by magnetization treating method. Microstructure of high-speed steel will be changed as a ...

  4. Soluble-oil cutting fluid

    Energy Technology Data Exchange (ETDEWEB)

    Rawlinson, A.P.; Whitby, R.D.; White, J.

    1989-04-11

    A composition for the preparation of a soluble oil for use in a cutting fluid comprises a mineral oil and, as an emuslifier, an effective amount of a sulfonate of a branched polymer of a C/sub 3/ to C/sub 5/ olefin. Preferably the polyolefin chain of the sulphonate has an average molecular weight in the range 275 to 560 and the polyolefin is polyisobutene. A soluble oil can be prepared from the above composition by the addition of a conventional corrosion inhibitor and diluted with water to make a cutting fluid. Advantages of the novel emulsifier are that it is resistant to breakdown by micro-organisms and does not require the addition of a coupling agent.

  5. Mine detection performance comparison between manual sweeping and tele-operated robotic system

    Science.gov (United States)

    Herman, Herman; Higgins, Todd; Falmier, Olga; Valois, Jean-Sebastien; McMahill, Jeff

    2010-04-01

    Mine detection is a dangerous and physically demanding task that is very well-suited for robotic applications. In the experiment described in this paper, we try to determine whether a remotely-operated robotic mine detection system equipped with a hand-held mine detector can match the performance of a human equipped with a hand-held mine detector. To achieve this objective, we developed the Robotic Mine Sweeper (RMS). The RMS platform is capable of accurately sweeping and mapping mine lanes using common detectors, such as the Minelab F3 Mine Detector or the AN/PSS-14. The RMS is fully remote controlled from a safe distance by a laptop via a redundant wireless connection link. Data collected from the mine detector and various sensors mounted on the robot are transmitted and logged in real-time to the remote user interface and simultaneously graphically displayed. In addition, a stereo color camera mounted on top of the robot sends a live picture of the terrain. The system plays audio feedback from the detector to further enhance the user's situational awareness. The user is trained to drag and drop various icons onto the user interface map to locate mines and non-mine clutter objects. We ran experiments with the RMS to compare its detection and false alarm rates with those obtained when the user physically sweeps the detectors in the field. The results of two trials: one with the Minelab F3, the other with the Cyterra AN/PSS-14 are presented here.

  6. Electrophoretic concentration and sweeping-micellar electrokinetic chromatography analysis of cationic drugs in water samples.

    Science.gov (United States)

    Wuethrich, Alain; Haddad, Paul R; Quirino, Joselito P

    2015-07-03

    Sample preparation by electrophoretic concentration, followed by analysis using sweeping-micellar electrokinetic chromatography, was studied as a green and simple analytical strategy for the trace analysis of cationic drugs in water samples. Electrophoretic concentration was conducted using 50 mmol/L ammonium acetate at pH 5 as acceptor electrolyte. Electrophoretic concentration was performed at 1.0 kV for 50 min and 0.5 kV and 15 min for purified and 10-fold diluted waste water samples, respectively. Sweeping-micellar electrokinetic chromatography was with 100 mmol/L sodium phosphate at pH 2, 100 mmol/L sodium dodecyl sulfate and 27.5%-v/v acetonitrile as separation electrolyte. The separation voltage was -20 kV, UV-detection was at 200 nm, and the acidified concentrate was injected for 36 s at 1 bar (or 72% of the total capillary length, 60 cm). Both purified water and 10-fold diluted waste water exhibited a linear range of two orders of concentration magnitude. The coefficient of determination, and intra- and interday repeatability were 0.991-0.997, 2.5-6.2, and 4.4-9.7%RSD (n=6), respectively, for purified water. The values were 0.991-0.997, 3.4-7.1, and 8.7-9.8%RSD (n=6), correspondingly, for 10-fold diluted waste water. The method detection limit was in the range from 0.04-0.09 to 1.20-6.97 ng/mL for purified and undiluted waste water, respectively.

  7. Planetesimal formation via sweep-up growth at the inner edge of dead zones

    Science.gov (United States)

    Drążkowska, J.; Windmark, F.; Dullemond, C. P.

    2013-08-01

    Context. The early stages of planet formation are still not well understood. Coagulation models have revealed numerous obstacles to the dust growth, such as the bouncing, fragmentation, and radial drift barriers. Gas drag causes rapid loss, and turbulence leads to generally destructive collisions between the dust aggregates. Aims: We study the interplay between dust coagulation and drift to determine the conditions in protoplanetary disk that support the formation of planetesimals. We focus on planetesimal formation via sweep-up and investigate whether it can take place in a realistic protoplanetary disk. Methods: We have developed a new numerical model that resolves the spatial distribution of dust in the radial and vertical dimensions. The model uses representative particles approach to follow the dust evolution in a protoplanetary disk. The coagulation and fragmentation of solids is taken into account in the Monte Carlo method. A collision model adopting the mass transfer effect, which can occur for different-sized dust aggregate collisions, is implemented. We focus on a protoplanetary disk that includes a pressure bump caused by a steep decline of turbulent viscosity around the snow line. Results: Our results show that high enough resolution of the vertical disk structure in dust coagulation codes is needed to obtain adequately short growth timescales, especially in the case of a low turbulence region. We find that a sharp radial variation in the turbulence strength at the inner edge of dead zone promotes planetesimal formation in several ways. It provides a pressure bump that efficiently prevents the dust from drifting inwards. It also causes a radial variation in the size of aggregates at which growth barriers occur, favoring the growth of large aggregates by sweeping up of small particles. In our model, by employing an ad hoc α viscosity change near the snow line, it is possible to grow planetesimals by incremental growth on timescales of approximately 105

  8. LARGE AERODYNAMIC FORCES ON A SWEEPING WING AT LOW REYNOLDS NUMBER

    Institute of Scientific and Technical Information of China (English)

    SUN Mao; WU Jianghao

    2004-01-01

    The aerodynamic forces and flow structure of a model insect wing is studied by solving the Navier-Stokes equations numerically. After an initial start from rest, the wing is made to execute an azimuthal rotation (sweeping) at a large angle of attack and constant angular velocity. The Reynolds number (Re) considered in the present note is 480 (Re is based on the mean chord length of the wing and the speed at 60% wing length from the wing root). During the constant-speed sweeping motion, the stall is absent and large and approximately constant lift and drag coefficients can be maintained. The mechanism for the absence of the stall or the maintenance of large aerodynamic force coefficients is as follows. Soon after the initial start, a vortex ring, which consists of the leading-edge vortex (LEV), the starting vortex, and the two wing-tip vortices, is formed in the wake of the wing. During the subsequent motion of the wing, a base-to-tip spanwise flow converts the vorticity in the LEV to the wing tip and the LEV keeps an approximately constant strength. This prevents the LEV from shedding. As a result,the size of the vortex ring increases approximately linearly with time, resulting in an approximately constant time rate of the first moment of vorticity, or approximately constant lift and drag coefficients.The variation of the relative velocity along the wing span causes a pressure gradient along the wingspan. The base-to-tip spanwise flow is mainly maintained by the pressure-gradient force.

  9. Acceleration of groundwater remediation by deep sweeps and vortex ejections induced by rapidly pulsed pumping

    Science.gov (United States)

    Kahler, David M.; Kabala, Zbigniew J.

    2016-05-01

    One key limiting factor to groundwater remediation is contaminant sequestered in pores whose contents do not mix well with the bulk flow. Mixing between well-connected (pores whose volume is flushed as water flows through the aquifer) and poorly connected pores (pores whose volume does not exchange readily when water flows through the aquifer) is of primary concern. Under steady flow, contaminants are effectively trapped in the poorly connected pores and are transferred only by molecular diffusion. This slow mixing process between pore types is a bottleneck to remediation. We present a novel rapidly pulsed pumping method that increases the mixing between these pore types. We do it in the context of pump-and-treat remediation because it is the most common remediation practice. In rapidly pulsed pumping, the increase in flow causes a deep sweep, which pushes the flow into poorly connected pores and sweeps out sequestered contaminants. The decrease in flow causes a vortex ejection, which causes the vortex within the poorly connected pore to emerge with contaminant. These actions are modeled with computational fluid mechanics to elucidate the individual mechanisms and determine how they function and interact. Cleanup of single and multiple poorly connected pore systems were simulated and show the acceleration possible. This technique can decrease the time and cost needed to remediate contaminated aquifers, which in the United States has been estimated to exceed $1 trillion. Since our rapidly pulsed pumping method enhances mixing between well-connected and poorly connected pores, it can be applied to other remediation schemes such as in situ methods.

  10. Amibiasis cutánea

    OpenAIRE

    Saravia Gómez, José; Rocha Posada, Hernando; Cortés B., Carlos; Ríos, Aníbal

    2011-01-01

    Los autores hacen un análisis de la etiopatogenia, de la anatomía patológica y del cuadro clínico de la amibiasis cutánea. Valoran los diferentes métodos de diagnóstico, el diagnóstico diferencial y el tratamiento de la entidad. Ilustran el trabajo con la presentación de un caso.

  11. Drill cuttings mount formation study

    Science.gov (United States)

    Teh, Su Yean; Koh, Hock Lye

    2014-07-01

    Oil, Gas and Energy sector has been identified as an essential driving force in the Malaysian Economic Transformation Programs (ETP). Recently confirmed discovery of many offshore oil and gas deposits in Malaysian waters has ignited new confidence in this sector. However, this has also spurred intense interest on safeguarding the health and environment of coastal waters in Malaysia from adverse impact resulting from offshore oil and gas production operation. Offshore discharge of spent drilling mud and rock cuttings is the least expensive and simplest option to dispose of large volumes of drilling wastes. But this onsite offshore disposal may have adverse environmental impacts on the water column and the seabed. It may also pose occupational health hazards to the workers living in the offshore platforms. It is therefore important to model the transport and deposition of drilling mud and rock cuttings in the sea to enable proper assessment of their adverse impacts on the environment and the workers. Further, accumulation of drill particles on the seabed may impede proper operation of pipelines on the seabed. In this paper, we present an in-house application model TUNA-PT developed to cater to local oil and gas industry needs to simulate the dispersion and mount formation of drill cuttings by offshore oil and gas exploration and production platforms. Using available data on Malaysian coastal waters, simulation analyses project a pile formation on the seabed with a maximum height of about 1 m and pile radius of around 30 to 50 m. Simulated pile heights are not sensitive to the heights of release of the cuttings as the sensitivity has been mitigated by the depth of water.

  12. Reservoir management cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  13. Evaluation of water-jet-assisted cutting

    National Research Council Canada - National Science Library

    1987-01-01

    Recent studies show that the addition of a water jet to the cutting bit can improve cutting performance in harder materials, significantly reduce respirable dust and bit wear, and increase particle size...

  14. European labs fight back against cuts

    CERN Multimedia

    König, R

    1997-01-01

    Germany's 1997 budget contains cuts amounting to 3.7% in funding of domestic research programs and in contributions to international labs. Contributions will be cut to the European Space Agency, the European Synchrotron facility and CERN.

  15. Eliminate Sweetened Drinks, Cut Kids' Sugar Intake

    Science.gov (United States)

    ... fullstory_161163.html Eliminate Sweetened Drinks, Cut Kids' Sugar Intake Average U.S. child consumes about 80 grams ... Looking for the quickest way to cut added sugar from your kid's diet? Eliminate sugar-sweetened drinks, ...

  16. Chip-ejection interference in cutting processes of modern cutting tools

    Institute of Scientific and Technical Information of China (English)

    师汉民

    1999-01-01

    Based on the “principle of minimum energy”, the basic characteristics of non-free cutting are studied; the phenomenon and the nature of chip-ejection interference commonly existing in the cutting process of modem cutting tools are explored. A "synthesis method of elementary cutting tools" is suggested for modeling the cutting process of modem complex cutting tools. The general equation governing the chip-ejection motion is deduced. Real examples of non-free cutting are analyzed and the theoretically predicted results are supported by the experimental data or facts. The sufficient and necessary conditions for eliminating chip-ejection interference and for realizing free cutting are given; the idea and the technical approach of "the principle of free cutting" are also discussed, and a feasible way for improving or optimizing the cutting performance of modem cutting tools is, therefore, found.

  17. Study on Ceramic Cutting by Plasma Arc

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Engineering ceramics are typical difficult-to-machine materials because of high hardness and brittleness. PAC (Plasma Arc Cutting) is a very important thermal cutting process and has been successfully used in cutting stainless steel and other difficult-to-machine alloys. PAC's application in cutting ceramics, however, is still limited because the most ceramics are not good electronic conducts, and transferred plasma arc cannot be produced between cathode and work-piece. So we presented a method of plasma ...

  18. Air in xylem vessels of cut flowers

    NARCIS (Netherlands)

    Nijsse, J.; Meeteren, van U.; Keijzer, C.J.

    2000-01-01

    Until now all studies on the role of air emboli in the water uptake of cut flowers describe indirect methods to demonstrate the presencFe of air in the plant tissues. Using cut chrysanthemum flowers, this report is the first one that directly visualises both air and water in xylem ducts of cut

  19. Spending and Cutting are Two Different Worlds

    DEFF Research Database (Denmark)

    Houlberg, Kurt; Olsen, Asmus Leth; Holm Pedersen, Lene

    2016-01-01

    deserving receive the highest cuts. Ideology matters as left-wing councillors prefer more vague categories when cutting and prioritise childcare and unemployment policies when increasing spending. In contrast, right-wing councillors prefer to cut administration and increase spending on roads....

  20. Optical Cutting Interruption Sensor for Fiber Lasers

    Directory of Open Access Journals (Sweden)

    Benedikt Adelmann

    2015-09-01

    Full Text Available We report on an optical sensor system attached to a 4 kW fiber laser cutting machine to detect cutting interruptions. The sensor records the thermal radiation from the process zone with a modified ring mirror and optical filter arrangement, which is placed between the cutting head and the collimator. The process radiation is sensed by a Si and InGaAs diode combination with the detected signals being digitalized with 20 kHz. To demonstrate the function of the sensor, signals arising during fusion cutting of 1 mm stainless steel and mild steel with and without cutting interruptions are evaluated and typical signatures derived. In the recorded signals the piercing process, the laser switch on and switch off point and waiting period are clearly resolved. To identify the cutting interruption, the signals of both Si and InGaAs diodes are high pass filtered and the signal fluctuation ranges being subsequently calculated. Introducing a correction factor, we identify that only in case of a cutting interruption the fluctuation range of the Si diode exceeds the InGaAs diode. This characteristic signature was successfully used to detect 80 cutting interruptions of 83 incomplete cuts (alpha error 3.6% and system recorded no cutting interruption from 110 faultless cuts (beta error of 0. This particularly high detection rate in combination with the easy integration of the sensor, highlight its potential for cutting interruption detection in industrial applications.

  1. 27 CFR 6.92 - Newspaper cuts.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Newspaper cuts. 6.92 Section 6.92 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.92 Newspaper cuts. Newspaper cuts, mats, or...

  2. Improving rooting uniformity in rose cuttings

    NARCIS (Netherlands)

    Telgen, van H.J.; Eveleens-Clark, B.A.; Garcia Victoria, N.

    2007-01-01

    Studies to improve rooting uniformity of single node stem cuttings for rose are reported. We found that the variation in shoot growth in a young rose crop depended on the variation in root number of the cuttings, which, in turn, was related to the auxin concentration applied to the cutting before ro

  3. From Sweeping to the Caress: Similarities and Discrepancies between Human and Non-Human Primates’ Pleasant Touch

    Science.gov (United States)

    Grandi, Laura C.

    2016-01-01

    Affective touch plays a key role in affiliative behavior, offering a mechanism for the formation and maintenance of social bonds among conspecifics, both in humans and non-human primates. Furthermore, it has been speculated that the CT fiber system is a specific coding channel for affiliative touch that occurs during skin-to-skin interactions with conspecifics. In humans, this touch is commonly referred to as the caress, and its correlation with the CT fiber system has been widely demonstrated. It has been hypothesized that the sweeping touch that occurs during grooming in non-human primates may modulate the CT fibers, with recent preliminary studies on rhesus monkeys supporting this hypothesis. The present mini-review proposes a comparison between the pleasant touch, caress and sweeping of humans and non-human primates, respectively. The currently available data was therefore reviewed regarding (i) the correlation between pleasant touch and CT fibers both in humans and non-human primates, (ii) the autonomic effects, (iii) the encoding at the central nervous system, (iv) the development from early life to adulthood, and (v) the potential applications of pleasant touch in the daily lives of both humans and non-human primates. Moreover, by considering both the similarities and discrepancies between the human caress and non-human primate sweeping, a possible evolutionary mechanism can be proposed that has developed from sweeping as a utilitarian action with affiliative meaning among monkeys, to the caress as a purely affective gesture associated with humans. PMID:27660620

  4. From sweeping to the caress: similarities and discrepancies between human and non-human primates' pleasant touch

    Directory of Open Access Journals (Sweden)

    Laura Clara Grandi

    2016-09-01

    Full Text Available Affective touch plays a key role in affiliative behavior, offering a mechanism for the formation and maintenance of social bonds among conspecifics, both in humans and non-human primates. Furthermore, it has been speculated that the CT fiber system is a specific coding channel for affiliative touch that occurs during skin-to-skin interactions with conspecifics. In humans, this touch is commonly referred to as the caress, and its correlation with the CT fiber system has been widely demonstrated. It has been hypothesized that the sweeping touch that occurs during grooming in non-human primates may modulate the CT fibers, with recent preliminary studies on rhesus monkeys supporting this hypothesis. The present mini-review proposes a comparison between the pleasant touch, caress and sweeping of humans and non-human primates, respectively. The currently available data was therefore reviewed regarding i the correlation between pleasant touch and CT fibers both in humans and non-human primates, ii the autonomic effects, iii the encoding at the central nervous system, iv the development from early life to adulthood, and v the potential applications of pleasant touch in the daily lives of both humans and non-human primates. Moreover, by considering both the similarities and discrepancies between the human caress and non-human primate sweeping, a possible evolutionary mechanism can be proposed that has developed from sweeping as a utilitarian action with affiliative meaning among monkeys, to the caress as a purely affective gesture associated with humans.

  5. Initial stages of anodic oxidation of silver in sodium hydroxide solution studied by potential sweep voltammetry and ellipsometry

    NARCIS (Netherlands)

    Droog, J.M.M.; Alderliesten, P.T.; Bootsma, G.A.

    1979-01-01

    The first stages of the oxidation of polycrystalline silver electrodes in NaOH solutions were studied by potential sweep voltammetry and ellipsometry. Formation of bulk Ag2O was found to be preceded by dissolution of silver species and deposition of a surface oxide. The equilibrium oxide coverage de

  6. A Comparison of Fast Marching, Fast Sweeping and Fast Iterative Methods for the Solution of the Eikonal Equation

    Directory of Open Access Journals (Sweden)

    A. Capozzoli

    2014-11-01

    Full Text Available We compare the computational performance of the Fast Marching Method, the Fast Sweeping Method and the Fast Iterative Method to determine a numerical solution to the eikonal equation. We point out how the Fast Iterative Method outperforms the other two thanks to its parallel processing capabilities.

  7. Processes involved in sweeping as sample enrichment method in cyclodextrin-modified micellar electrokinetic chromatography of hydrophobic basic analytes.

    Science.gov (United States)

    El-Awady, Mohamed; Pyell, Ute

    2014-03-01

    Sweeping is an enrichment method in MEKC, which includes following steps: stacking/destacking of the micelles, sweeping of analyte by the stacked/destacked micelles, destacking/stacking of the swept analyte zone and additional focusing/defocusing due to the retention factor gradient effect (RFGE). In this study, we investigate additional processes, regarding online focusing in cyclodextrin-modified MEKC (CD-MEKC) of hydrophobic basic analytes: dynamic pH junction (sample with pH different from that of BGE) and adsorption of analyte onto the capillary wall within the sample zone. It is demonstrated that the developed method for the assessment of the sweeping efficiency is also applicable to CD-MEKC taking ethylparaben as an example of acidic analytes and desloratadine as an example of basic analytes using different types of β-cyclodextrin. Our previous results regarding RFGE as an additional focusing/defocusing effect in sweeping-MEKC are confirmed for the case that the apparent distribution coefficient differs for the sample and the BGE due to a different content of the complex-forming agent cyclodextrin and due to a pH difference between the sample and the BGE. Despite being significantly more hydrophobic than ethylparaben, desloratadine shows an unexpectedly low enrichment factor. This enrichment factor is nearly unaffected by the addition of CD to the BGE. This unexpected behavior is attributed to wall adsorption of the protonated hydrophobic basic analyte within the sample zone, which significantly counteracts the sweeping process. This assumption is corroborated by an improvement in the enrichment factor achieved via addition of a dynamic coating agent (triethylamine) to the sample solution. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Automated Laser Cutting In Three Dimensions

    Science.gov (United States)

    Bird, Lisa T.; Yvanovich, Mark A.; Angell, Terry R.; Bishop, Patricia J.; Dai, Weimin; Dobbs, Robert D.; He, Mingli; Minardi, Antonio; Shelton, Bret A.

    1995-01-01

    Computer-controlled machine-tool system uses laser beam assisted by directed flow of air to cut refractory materials into complex three-dimensional shapes. Velocity, position, and angle of cut varied. In original application, materials in question were thermally insulating thick blankets and tiles used on space shuttle. System shapes tile to concave or convex contours and cuts beveled edges on blanket, without cutting through outer layer of quartz fabric part of blanket. For safety, system entirely enclosed to prevent escape of laser energy. No dust generated during cutting operation - all material vaporized; larger solid chips dislodged from workpiece easily removed later.

  9. Effect of Type of Cutting Tips on Cutting Forces in Turning

    Directory of Open Access Journals (Sweden)

    Polák Pavel

    2014-10-01

    Full Text Available The aim of this article is to demonstrate the efect of cutting materials and geometry of cutting tips on cutting forces in turning as well as the quality and precision of machined surface. The experiment focuses on measuring cutting forces when turning a sample of steel 11 523 at a constant feed rate and cut depth and at varying speeds of a spindle. Measurements were made using exchangeable cutting tips of diferent types. The results will be evaluated in terms of the impact of diferent characteristics of cutting tips and variable spindle speeds.

  10. Clinically lean; "cutting the crap".

    Science.gov (United States)

    Caldwell, G

    2012-01-01

    Proponents of Lean Philosophy believe that successful businesses must reduce waste in working time and resources to a minimum, and maximise their use in productive work. The productive work of the Acute Medical Unit is to provide effective clinical management to a daily cohort of acutely ill patients. Many Clinicians are cynical about Lean. In this article, Dr Caldwell discusses how many clinicians complain of too much crap in the workplace, which gets in the way of swift, safe high quality clinical care. He argues that "Cutting the Crap" in the Acute Medical Unit is entirely consistent with Lean approaches to management of complex systems.

  11. Rooting of stem cuttings of ixora

    Directory of Open Access Journals (Sweden)

    Aline De Souza Silva

    2015-08-01

    Full Text Available The ixora is ornamental plant widely used in landscaping. In order to maximize the propagation of cuts, we evaluated the concentrations of auxin (indolbutiric acid and the presence of leaves on the rooting in cuts of Ixora coccinea L. The experiment was conducted in randomized block design, in factorial design 3x4, with three types of cuts (without leaf, with two or four leaves, four concentrations of indolbutiric acid (0, 1000, 2000 and 4000 mg L-1, with four replications and 10 cuts in each experimental unit. After 53 days of implantation the experiment, evaluated the survival(%, rooting(%, sprouting(%, formation of callus(%, number, length and biomass of roots formed. The interaction of the type of cuts with concentrations of auxin was not significant for any of the variables analyzed. The survival of cuttings was not influenced by the treatments. Cuts with two or four leaves presented rooting and length of roots above the cuttings without leaves. The application of auxin does not substitute the presence of leaf in cuts of ixora in vegetative propagation. The vegetative propagation by cut of ixora can be made without application of auxin, and the leaves must be maintained in the cuttings.

  12. Numerical investigation of collector cooling for a 1 MW ITER gyrotron operated with vertical sweeping

    Energy Technology Data Exchange (ETDEWEB)

    Savoldi, Laura; Bertani, Cristina [Dipartimento Energia, Politecnico di Torino (Italy); Cau, Francesca; Cismondi, Fabio [Fusion for Energy, Barcelona (Spain); Gantenbein, Gerd; Illy, Stefan [KIT, Karlsruhe (Germany); Monni, Grazia [Dipartimento Energia, Politecnico di Torino (Italy); Zanino, Roberto, E-mail: roberto.zanino@polito.it [Dipartimento Energia, Politecnico di Torino (Italy)

    2015-11-15

    The present gyrotron designs for EC plasma heating in nuclear fusion reactors require the safe exhaust of a power comparable to that injected into the plasma, in order to keep the maximum temperature below the acceptable value of 300 °C. In this paper, the commercial computational fluid dynamics (CFD) software STAR-CCM+{sup ®} is used to analyze the thermal performance of the annular copper collector of a 1 MW ITER gyrotron, equipped with a hypervapotron structure made of annular fins with rectangular cavities of aspect ratio (depth/width) = 3, cooled by highly subcooled (90–100 °C) pressurized water flowing at ∼4 m/s. It is assumed that the simple vertical sweeping strategy is used to reduce the very high peak heat flux on the collector (up to 30 MW/m{sup 2} transient, 5 MW/m{sup 2} time average), due to the spent electron beam. The 2D steady-state conjugate heat transfer problem is solved assuming azimuthal symmetry and accounting for 2-phase flow. The single-cavity flow and heat transfer problem is considered first, to optimize the mesh and the selection of the turbulence model. For the operating conditions considered in this paper, the full collector (100+ cavities) solution shows that boiling occurs only in a limited number of cavities close to the peaks of the heat flux, with the vapor remaining trapped in the bottom of the cavities, i.e. no full hypervapotron regime should be achieved in these operating conditions. The steady-state analysis allows the numerical evaluation of the heat transfer coefficients between Cu and water; these are then used as input for the simplified, purely thermal (solid only) analysis of the actual transient problem for the full collector. The results of the simplified model, which allows a huge reduction of the computational effort, are successfully benchmarked against those of a comprehensive thermal–hydraulic simulation. The computed peak Cu temperature is below the acceptable limit under the steady-state (time averaged

  13. The center-cut solution.

    Science.gov (United States)

    Firnstahl, T W

    1993-01-01

    Timothy Firnstahl owns five successful restaurants in Seattle, but he recently came very close to owning none. In the early 1990s, he found himself, like so many restauranteurs, facing rising costs, inefficient management, and a recession. Confronting financial annihilation, Firnstahl had to act quickly: since he had no peripherals to trim, he cut off the head of his company. Remarkably, it worked. Firnstahl's problem was his new and innovative restaurant, Sharps Fresh Roasting. The heart of the Sharps concept was a unique long-roasting technique that made lean, inexpensive meats taste as juicy and delicious as fattier, expensive cuts. The process also lent itself to faster service and lower labor costs. But it wasn't working. Sharps wasn't breaking even, and his other restaurants couldn't make up the difference. He needed a solution fast. Firnstahl got his answer from Mikhail Gorbachev: slash the centralized command and liberate the company. In doing so, he would also transfer virtually all power and responsibility to his line managers. And after five months of intensive study and planning, he accomplished what he set out to do. He fired most of his corporate staff, empowered his restaurant managers with "100% Power and Responsibility," and, finally, undertook a massive promotion campaign. A year later, Sharps Fresh Roasting is the gold mine Firnstahl always believed it could be. He's done away with bureaucracy and turned business around in a down market. All this because his managers are managing themselves.

  14. Effects of heat on cut mark characteristics.

    Science.gov (United States)

    Waltenberger, Lukas; Schutkowski, Holger

    2017-02-01

    Cut marks on bones provide crucial information about tools used and their mode of application, both in archaeological and forensic contexts. Despite a substantial amount of research on cut mark analysis and the influence of fire on bones (shrinkage, fracture pattern, recrystallisation), there is still a lack of knowledge in cut mark analysis on burnt remains. This study provides information about heat alteration of cut marks and whether consistent features can be observed that allow direct interpretation of the implemented tools used. In a controlled experiment, cut marks (n=25) were inflicted on pig ribs (n=7) with a kitchen knife and examined using micro-CT and digital microscopy. The methods were compared in terms of their efficacy in recording cut marks on native and heat-treated bones. Statistical analysis demonstrates that floor angles and the maximum slope height of cuts undergo significant alteration, whereas width, depth, floor radius, slope, and opening angle remain stable. Micro-CT and digital microscopy are both suitable methods for cut mark analysis. However, significant differences in measurements were detected between both methods, as micro-CT is less accurate due to the lower resolution. Moreover, stabbing led to micro-fissures surrounding the cuts, which might also influence the alteration of cut marks.

  15. A Support Vector Machine Approach for Truncated Fingerprint Image Detection from Sweeping Fingerprint Sensors

    Directory of Open Access Journals (Sweden)

    Chi-Jim Chen

    2015-03-01

    Full Text Available A sweeping fingerprint sensor converts fingerprints on a row by row basis through image reconstruction techniques. However, a built fingerprint image might appear to be truncated and distorted when the finger was swept across a fingerprint sensor at a non-linear speed. If the truncated fingerprint images were enrolled as reference targets and collected by any automated fingerprint identification system (AFIS, successful prediction rates for fingerprint matching applications would be decreased significantly. In this paper, a novel and effective methodology with low time computational complexity was developed for detecting truncated fingerprints in a real time manner. Several filtering rules were implemented to validate existences of truncated fingerprints. In addition, a machine learning method of supported vector machine (SVM, based on the principle of structural risk minimization, was applied to reject pseudo truncated fingerprints containing similar characteristics of truncated ones. The experimental result has shown that an accuracy rate of 90.7% was achieved by successfully identifying truncated fingerprint images from testing images before AFIS enrollment procedures. The proposed effective and efficient methodology can be extensively applied to all existing fingerprint matching systems as a preliminary quality control prior to construction of fingerprint templates.

  16. Dissolved oxygen transfer to sediments by sweep and eject motions in aquatic environments

    Science.gov (United States)

    O'Connor, B.L.; Hondzo, Miki

    2008-01-01

    Dissolved oxygen (DO) concentrations were quantified near the sediment-water interface to evaluate DO transfer to sediments in a laboratory recirculating flume and open channel under varying fluid-flow conditions. DO concentration fluctuations were observed within the diffusive sublayer, as defined by the time-averaged DO concentration gradient near the sediment-water interface. Evaluation of the DO concentration fluctuations along with detailed fluid-flow characterizations were used to quantify quasi-periodic sweep and eject motions (bursting events) near the sediments. Bursting events dominated the Reynolds shear stresses responsible for momentum and mass fluctuations near the sediment bed. Two independent methods for detecting bursting events using DO concentration and velocity data produced consistent results. The average time between bursting events was scaled with wall variables and was incorporated into a similarity model to describe the dimensionless mass transfer coefficient (Sherwood number, Sh) in terms of the Reynolds number, Re, and Schmidt number, Sc, which described transport in the flow. The scaling of bursting events was employed with the similarity model to quantify DO transfer to sediments and results showed a high degree of agreement with experimental data. ?? 2008, by the American Society of Limnology and Oceanography, Inc.

  17. The yule approximation for the site frequency spectrum after a selective sweep.

    Science.gov (United States)

    Bossert, Sebastian; Pfaffelhuber, Peter

    2013-01-01

    In the area of evolutionary theory, a key question is which portions of the genome of a species are targets of natural selection. Genetic hitchhiking is a theoretical concept that has helped to identify various such targets in natural populations. In the presence of recombination, a severe reduction in sequence diversity is expected around a strongly beneficial allele. The site frequency spectrum is an important tool in genome scans for selection and is composed of the numbers S(1),...,S(n-1), where S(k) is the number of single nucleotide polymorphisms (SNPs) present in k from n individuals. Previous work has shown that both the number of low- and high-frequency variants are elevated relative to neutral evolution when a strongly beneficial allele fixes. Here, we follow a recent investigation of genetic hitchhiking using a marked Yule process to obtain an analytical prediction of the site frequency spectrum in a panmictic population at the time of fixation of a highly beneficial mutation. We combine standard results from the neutral case with the effects of a selective sweep. As simulations show, the resulting formula produces predictions that are more accurate than previous approaches for the whole frequency spectrum. In particular, the formula correctly predicts the elevation of low- and high-frequency variants and is significantly more accurate than previously derived formulas for intermediate frequency variants.

  18. Distinguishing between Selective Sweeps from Standing Variation and from a De Novo Mutation

    DEFF Research Database (Denmark)

    Peter, Benjamin M.; Huerta-Sanchez, Emilia; Nielsen, Rasmus

    2012-01-01

    An outstanding question in human genetics has been the degree to which adaptation occurs from standing genetic variation or from de novo mutations. Here, we combine several common statistics used to detect selection in an Approximate Bayesian Computation (ABC) framework, with the goal of discrimi......An outstanding question in human genetics has been the degree to which adaptation occurs from standing genetic variation or from de novo mutations. Here, we combine several common statistics used to detect selection in an Approximate Bayesian Computation (ABC) framework, with the goal...... of discriminating between models of selection and providing estimates of the age of selected alleles and the selection coefficients acting on them. We use simulations to assess the power and accuracy of our method and apply it to seven of the strongest sweeps currently known in humans. We identify two genes, ASPM...... and PSCA, that are most likely affected by selection on standing variation; and we find three genes, ADH1B, LCT, and EDAR, in which the adaptive alleles seem to have swept from a new mutation. We also confirm evidence of selection for one further gene, TRPV6. In one gene, G6PD, neither neutral models nor...

  19. Sweeping away protein aggregation with entropic bristles: intrinsically disordered protein fusions enhance soluble expression.

    Science.gov (United States)

    Santner, Aaron A; Croy, Carrie H; Vasanwala, Farha H; Uversky, Vladimir N; Van, Ya-Yue J; Dunker, A Keith

    2012-09-18

    Intrinsically disordered, highly charged protein sequences act as entropic bristles (EBs), which, when translationally fused to partner proteins, serve as effective solubilizers by creating both a large favorable surface area for water interactions and large excluded volumes around the partner. By extending away from the partner and sweeping out large molecules, EBs can allow the target protein to fold free from interference. Using both naturally occurring and artificial polypeptides, we demonstrate the successful implementation of intrinsically disordered fusions as protein solubilizers. The artificial fusions discussed herein have a low level of sequence complexity and a high net charge but are diversified by means of distinctive amino acid compositions and lengths. Using 6xHis fusions as controls, soluble protein expression enhancements from 65% (EB60A) to 100% (EB250) were observed for a 20-protein portfolio. Additionally, these EBs were able to more effectively solubilize targets compared to frequently used fusions such as maltose-binding protein, glutathione S-transferase, thioredoxin, and N utilization substance A. Finally, although these EBs possess very distinct physiochemical properties, they did not perturb the structure, conformational stability, or function of the green fluorescent protein or the glutathione S-transferase protein. This work thus illustrates the successful de novo design of intrinsically disordered fusions and presents a promising technology and complementary resource for researchers attempting to solubilize recalcitrant proteins.

  20. The effect of contrast polarity reversal on face detection: evidence of perceptual asymmetry from sweep VEP.

    Science.gov (United States)

    Liu-Shuang, Joan; Ales, Justin M; Rossion, Bruno; Norcia, Anthony M

    2015-03-01

    Contrast polarity inversion (i.e., turning dark regions light and vice versa) impairs face perception. We investigated the perceptual asymmetry between positive and negative polarity faces (matched for overall luminance) using a sweep VEP approach in the context of face detection (Journal of Vision 12 (2012) 1-18). Phase-scrambled face stimuli alternated at a rate of 3 Hz (6 images/s). The phase coherence of every other stimulus was parametrically increased so that a face gradually emerged over a 20-s stimulation sequence, leading to a 3 Hz response reflecting face detection. Contrary to the 6 Hz response, reflecting low-level visual processing, this 3 Hz response was larger and emerged earlier over right occipito-temporal channels for positive than negative polarity faces. Moreover, the 3 Hz response emerged abruptly to positive polarity faces, whereas it increased linearly for negative polarity faces. In another condition, alternating between a positive and a negative polarity face also elicited a strong 3 Hz response, indicating an asymmetrical representation of positive and negative polarity faces even at supra-threshold levels (i.e., when both stimuli were perceived as faces). Overall, these findings demonstrate distinct perceptual representations of positive and negative polarity faces, independently of low-level cues, and suggest qualitatively different detection processes (template-based matching for positive polarity faces vs. linear accumulation of evidence for negative polarity faces).

  1. Diversity of lactase persistence alleles in Ethiopia: signature of a soft selective sweep.

    Science.gov (United States)

    Jones, Bryony L; Raga, Tamiru O; Liebert, Anke; Zmarz, Pawel; Bekele, Endashaw; Danielsen, E Thomas; Olsen, Anders Krüger; Bradman, Neil; Troelsen, Jesper T; Swallow, Dallas M

    2013-09-05

    The persistent expression of lactase into adulthood in humans is a recent genetic adaptation that allows the consumption of milk from other mammals after weaning. In Europe, a single allele (-13910(∗)T, rs4988235) in an upstream region that acts as an enhancer to the expression of the lactase gene LCT is responsible for lactase persistence and appears to have been under strong directional selection in the last 5,000 years, evidenced by the widespread occurrence of this allele on an extended haplotype. In Africa and the Middle East, the situation is more complicated and at least three other alleles (-13907(∗)G, rs41525747; -13915(∗)G, rs41380347; -14010(∗)C, rs145946881) in the same LCT enhancer region can cause continued lactase expression. Here we examine the LCT enhancer sequence in a large lactose-tolerance-tested Ethiopian cohort of more than 350 individuals. We show that a further SNP, -14009T>G (ss 820486563), is significantly associated with lactose-digester status, and in vitro functional tests confirm that the -14009(∗)G allele also increases expression of an LCT promoter construct. The derived alleles in the LCT enhancer region are spread through several ethnic groups, and we report a greater genetic diversity in lactose digesters than in nondigesters. By examining flanking markers to control for the effects of mutation and demography, we further describe, from empirical evidence, the signature of a soft selective sweep.

  2. A Sweeping based Kinematic Simulation for the Stably Stratified Surface Layer

    Science.gov (United States)

    Ghate, Aditya; Lele, Sanjiva

    2014-11-01

    A Kinematic Simulation (KS) for a statistically stationary and stably stratified surface layer is proposed. The Fourier coefficients are obtained by numerically solving the linearized NS equations with Boussinesq approximation in spectral space, under the assumption of ``rapid'' deformation (RDT) due to combined shear and stratification. The linearization of RDT, which is unrealistic for the surface layer, is rectified using Mann's (JFM, 1994) idea of wavenumber dependent eddy lifetime. The input parameters required by the KS are estimated using either Monin-Obukhov theory, or an appropriate Second Moment Closure. In order to overcome the frozen turbulence hypothesis made in the Mann model, we incorporate inter-scale ``sweeping'' of eddies following the ideas of Fung et al. (JFM, 1992), along with temporal decorrelation associated with the natural eddy time scale. The solenoidal velocity field generated by the KS allows inclusion of a wide range of scales with correct space-time correlations, making it ideal to investigate particle dispersion in a stably stratified environment, and can also serve as inflow for the study of Wind Farm-PBL interactions. The effect of varying Obukhov length will be discussed by analyzing the frozen Eulerian spectra and Lagrangian particle dispersion.

  3. Linear sweep voltametry studies on oxygen reduction of some oxides in alkaline electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Ananth, M.V. [Ni-MH Section, Electrochemical Power Sources Division, Central Electrochemical Research Institute, Karaikudi, 630 006 Tamil Nadu (India); Giridhar, V.V. [Electrodics and Electrocatalysis (EEC) Division, Central Electrochemical Research Institute, Karaikudi, 630 006 Tamil Nadu (India); Renuga, K. [Department of Chemistry, Thiagarajar College, Madurai 625 009 (India)

    2009-01-15

    The study uses linear sweep voltametry (LSV) to observe the efficiency of oxygen reduction on some oxides and their mixtures in 6 M KOH at 25 C. The investigated materials are Ag{sub 2}O, MnO{sub 2}, Sm{sub 2}O{sub 3}, Dy{sub 2}O{sub 3} and NdO{sub 2}. The electrocatalytic oxygen reduction reactions (ORR) on Teflon-bonded, oxide + graphite electrodes are studied. The oxygen reduction potentials for electrodes containing these materials as catalyst are seen as -60.67, -270.31, -111, -159.58 and -130.24 mV, respectively. Mixture combinations of these oxides give a higher ORR peak current thereby showing evidence of synergetic effect. Air-MH cells using some of the above investigated oxides as catalyst for air electrode are constructed and studied. Best performance is obtained with silver oxide. The LSV findings are in accordance with air-MH cell charge/discharge experiments and for best performance prefer shift of the ORR onset potential to more positive positions. (author)

  4. Comparison of Snellen acuity and objective assessment using the spatial frequency sweep PVER.

    Science.gov (United States)

    Arai, M; Katsumi, O; Paranhos, F R; Lopes De Faria, J M; Hirose, T

    1997-07-01

    We compared the vision objectively assessed by spatial frequency sweep pattern-reversal visual-evoked response (SPVER) with the Snellen acuity in patients. SPVER acuity and Snellen acuity were measured in 100 patients with various ocular pathologies, including macular diseases, diffuse retinal degeneration, optic nerve diseases, glaucoma, and high myopia. For SPVER, 10 sinusoidally modulated vertical gratings were presented as stimuli. The responses were averaged and displayed through the discrete Fourier transform on the monitor display. The PVER acuity was determined by extrapolating the SPVER amplitude-spatial frequency function to baseline. Vision ranged from 20/15 to 20/400 with Snellen acuity, and from 20/25 to 20/190 with SPVER. The overall correlation between the two acuities was r = 0.666. The correlation varied from r = 0.895 in eyes with glaucoma to r = 0.436 in eyes with optic nerve disease. Seventy-seven eyes (77%) had a visual acuity agreement of within 1.0 octave between the two measurements. The SPVER acuity and the Snellen acuity correlated to a certain degree. Discrepancies were found in certain diseases, with the highest disparity in patients with optic nerve disease. We conclude that the SPVER is effective in estimating vision objectively, particularly in patients in whom the standard Snellen test is impossible to perform or yields unreliable results.

  5. Production of artificial ionospheric layers by frequency sweeping near the 2nd gyroharmonic

    Directory of Open Access Journals (Sweden)

    T. Pedersen

    2011-01-01

    Full Text Available Artificial ionospheric plasmas descending from the background F-region have been observed on multiple occasions at the High Frequency Active Auroral Research Program (HAARP facility since it reached full 3.6 MW power. Proximity of the transmitter frequency to the 2nd harmonic of the electron gyrofrequency (2fce has been noted as a requirement for their occurrence, and their disappearance after only a few minutes has been attributed to the increasing frequency mismatch at lower altitudes. We report new experiments employing frequency sweeps to match 2fce in the artificial plasmas as they descend. In addition to revealing the dependence on the 2fce resonance, this technique reliably produces descending plasmas in multiple transmitter beam positions and appears to increase their stability and lifetime. High-speed ionosonde measurements are used to monitor the altitude and density of the artificial plasmas during both the formation and decay stages.

  6. Identification of local selective sweeps in human populations since the exodus from Africa.

    Science.gov (United States)

    Johansson, Asa; Gyllensten, Ulf

    2008-06-01

    Selection on the human genome has been studied using comparative genomics and SNP architecture in the lineage leading to modern humans. In connection with the African exodus and colonization of other continents, human populations have adapted to a range of different environmental conditions. Using a new method that jointly analyses haplotype block length and allele frequency variation (F(ST)) within and between populations, we have identified chromosomal regions that are candidates for having been affected by local selection. Based on 1.6 million SNPs typed in 71 individuals of African American, European American and Han Chinese descent, we have identified a number of genes and non-coding regions that are candidates for having been subjected to local positive selection during the last 100 000 years. Among these genes are those involved in skin pigmentation (SLC24A5) and diet adaptation (LCT). The list of genes implicated in these local selective sweeps overlap partly with those implicated in other studies of human populations using other methods, but show little overlap with those postulated to have been under selection in the 5-7 myr since the divergence of the ancestors of human and chimpanzee. Our analysis provides focal points in the genome for detailed studies of evolutionary events that have shaped human populations as they explored different regions of the world.

  7. Linearity enhancement of TVGA based on adaptive sweep optimisation in monostatic radar receiver

    Science.gov (United States)

    Almslmany, Amir; Wang, Caiyun; Cao, Qunsheng

    2016-08-01

    The limited input dynamic power range of the radar receiver and the power loss due to the targets' ranges are two potential problems in the radar receivers. This paper proposes a model based on the time-varying gain amplifier (TVGA) to compensate the power loss from the targets' ranges, and using the negative impedance compensation technique to enhance the TVGA linearity based on Volterra series. The simulation has been done based on adaptive sweep optimisation (ASO) using advanced design system (ADS) and Matlab. It shows that the suppression of the third-order intermodulation products (IMR3) was carried out for two-tone test, the high-gain accuracy improved by 3 dB, and the high linearity IMR3 improved by 14 dB. The monostatic radar system was tested to detect three targets at different ranges and to compare its probability of detection with the prior models; the results show that the probability of detection has been increased for ASO/TVGA.

  8. Acetate and phosphate anion adsorption linear sweep voltammograms simulated using density functional theory

    KAUST Repository

    Savizi, Iman Shahidi Pour

    2011-04-01

    Specific adsorption of anions to electrode surfaces may alter the rates of electrocatalytic reactions. Density functional theory (DFT) methods are used to predict the adsorption free energy of acetate and phosphate anions as a function of Pt(1 1 1) electrode potential. Four models of the electrode potential are used including a simple vacuum slab model, an applied electric field model with and without the inclusion of a solvating water bi-layer, and the double reference model. The linear sweep voltammogram (LSV) due to anion adsorption is simulated using the DFT results. The inclusion of solvation at the electrochemical interface is necessary for accurately predicting the adsorption peak position. The Langmuir model is sufficient for predicting the adsorption peak shape, indicating coverage effects are minor in altering the LSV for acetate and phosphate adsorption. Anion adsorption peak positions are determined for solution phase anion concentrations present in microbial fuel cells and microbial electrolysis cells and discussion is provided as to the impact of anion adsorption on oxygen reduction and hydrogen evolution reaction rates in these devices. © 2011 Elsevier Ltd. All rights reserved.

  9. Effects of inlet circumferential fluctuation on the sweep aerodynamic performance of axial fans/compressors

    Science.gov (United States)

    Gui, Xingmin; Zhu, Fang; Wan, Ke; Jin, Donghai

    2013-10-01

    Swept blades have been widely used in the transonic fan/compressor of aircraft engines with the aids of 3D CFD simulation since the design concept of controlling the shock structure was firstly proposed and successfully tested by Dr. Wennerstrom in the 1980s. However, some disadvantage phenomenon has also been induced by excessively 3D blade geometries on the structure stress insufficiency, vibration and reliability. Much confusion in the procedure of design practice leading us to recognize a new view on the flow mechanism of sweep aerodynamical induction: the new radial equilibrium established by the influence of inlet circumferential fluctuation (CF) changes the inlet flows of blading and induces the performance modification of axial fans/compressors blade. The view is verified by simplified models through numerical simulation and circumferentially averaged analysis in the present paper. The results show that the CF source items which originate from design parameters, such as the spanwise distributions of the loading and blading geometries, contribute to the changing of averaged incidence spanwise distribution, and further more affect the performance of axial fans/compressors with swept blades.

  10. A Support Vector Machine Approach for Truncated Fingerprint Image Detection from Sweeping Fingerprint Sensors

    Science.gov (United States)

    Chen, Chi-Jim; Pai, Tun-Wen; Cheng, Mox

    2015-01-01

    A sweeping fingerprint sensor converts fingerprints on a row by row basis through image reconstruction techniques. However, a built fingerprint image might appear to be truncated and distorted when the finger was swept across a fingerprint sensor at a non-linear speed. If the truncated fingerprint images were enrolled as reference targets and collected by any automated fingerprint identification system (AFIS), successful prediction rates for fingerprint matching applications would be decreased significantly. In this paper, a novel and effective methodology with low time computational complexity was developed for detecting truncated fingerprints in a real time manner. Several filtering rules were implemented to validate existences of truncated fingerprints. In addition, a machine learning method of supported vector machine (SVM), based on the principle of structural risk minimization, was applied to reject pseudo truncated fingerprints containing similar characteristics of truncated ones. The experimental result has shown that an accuracy rate of 90.7% was achieved by successfully identifying truncated fingerprint images from testing images before AFIS enrollment procedures. The proposed effective and efficient methodology can be extensively applied to all existing fingerprint matching systems as a preliminary quality control prior to construction of fingerprint templates. PMID:25835186

  11. Computational wing design in support of an NLF variable sweep transition flight experiment. [Natural Laminar Flow

    Science.gov (United States)

    Waggoner, E. G.; Campbell, R. L.; Phillips, P. S.

    1985-01-01

    A natural laminar flow outer panel wing glove has been designed for a variable sweep fighter aircraft using state-of-the-art computational techniques. Testing of the design will yield wing pressure and boundary-layer data under actual flight conditions and environment. These data will be used to enhance the understanding of the interaction between crossflow and Tollmien-Schlichting disturbances on boundary-layer transition. The outer wing panel was contoured such that a wide range of favorable pressure gradients could be obtained on the wing upper surface. Extensive computations were performed to support the design effort which relied on two- and three-dimensional transonic design and analysis techniques. A detailed description of the design procedure that evolved during this study is presented. Results on intermediate designs at various stages in the design process demonstrate how the various physical and aerodynamic constraints were integrated into the design. Final results of the glove design analyzed as part of the complete aircraft configuration with a full-potential wing/body analysis code indicate that the aerodynamic design objectives were met.

  12. Determination of Sulpiride by Linear Sweep Stripping Voltammetry at a Mercury Electrode

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper reports the electrochemical properties of sulpiride at a mercury electrode, especially its adsorptive characteristic. Sulpiride dissolved in a supporting electrolyte of a McIlvaine buffer at pH 6.8 represents a sensitive and well defined reduction wave by linear sweep stripping voltammetry. This method is based on the pre-concentration and the reduction of sulpiride at a hung mercury drop electrode. The reduction peak potential is -1.72 V(vs. Ag-AgCl) and the peak current is proportional to the concentration of sulpiride in the range of 0.1-0.6 μg/mL. The detection limit is 0.025 μg/mL obtained under the experimental conditions selected in this work. The electrochemical properties of this system were investigated, and the proposed method was applied to the determination of sulpiride in pharmaceutical tablets with satisfactory results. It was compared well with the UV spectrophotometric method, showing a superior sensitivity.

  13. Polysulfide transport through separators measured by a linear voltage sweep method

    Science.gov (United States)

    Cui, Yi; Fu, Yongzhu

    2015-07-01

    Shuttle of polysulfide from the sulfur cathode to lithium metal anode in rechargeable lithium-sulfur batteries is a critical issue hindering cycling efficiency and life. Several approaches have been developed to minimize it including polysulfide-blocking separators; there is a need for measuring polysulfide transport through separators. We here show a linear voltage sweep method to measure anodic (oxidization) current of polysulfide crossed separators, which can be used as a quantitative measurement of the polysulfide transport. The electrochemical oxidation of polysulfide is diffusion controlled. The electrical charge in Coulombs produced by the oxidation of polysulfide is linearly related to the concentration of polysulfide within a certain range (≤0.5 M). Separators with a high porosity (large pore size) show high anodic currents, resulting in fast capacity degradation and low Coulombic efficiencies in Li-S cells. These results demonstrate this method can be used to correlate the polysulfide transport through separators with the separator structure and battery performance, therefore provide guidance for developing new separators for lithium-sulfur batteries.

  14. Determination of bosentan in pharmaceutical preparations by linear sweep, square wave and differential pulse voltammetry methods.

    Science.gov (United States)

    Atila, Alptug; Yilmaz, Bilal

    2015-01-01

    In this study, simple, fast and reliable cyclic voltammetry (CV), linear sweep voltammetry (LSV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV) methods were developed and validated for determination of bosentan in pharmaceutical preparations. The proposed methods were based on electrochemical oxidation of bosentan at platinum electrode in acetonitrile solution containing 0.1 M TBACIO4. The well-defined oxidation peak was observed at 1.21 V. The calibration curves were linear for bosentan at the concentration range of 5-40 µg/mL for LSV and 5-35 µg/mL for SWV and DPV methods, respectively. Intra- and inter-day precision values for bosentan were less than 4.92, and accuracy (relative error) was better than 6.29%. The mean recovery of bosentan was 100.7% for pharmaceutical preparations. No interference was found from two tablet excipients at the selected assay conditions. Developed methods in this study are accurate, precise and can be easily applied to Tracleer and Diamond tablets as pharmaceutical preparation.

  15. Testing of Commercial Cutting Heads for Abrasive Water Jet Technology

    OpenAIRE

    Klich, J. (Jiří); Hlaváček, P.; M. Zeleňák; Sitek, L. (Libor); Foldyna, J. (Josef)

    2013-01-01

    Five different cutting heads designed for cutting by high-speed abrasive water jet technology were tested from cutting ability point of view. Straight kerfs were cut in several metal materials by abrasive water jet. Material removal volume was determined as a measure of performance of specific cutting head. Quality of cutting surface was observed, too. Results are compared and discussed.

  16. Ceramic cutting tools materials, development and performance

    CERN Document Server

    Whitney, E Dow

    1994-01-01

    Interest in ceramics as a high speed cutting tool material is based primarily on favorable material properties. As a class of materials, ceramics possess high melting points, excellent hardness and good wear resistance. Unlike most metals, hardness levels in ceramics generally remain high at elevated temperatures which means that cutting tip integrity is relatively unaffected at high cutting speeds. Ceramics are also chemically inert against most workmetals.

  17. A cactus theorem for end cuts

    CERN Document Server

    Evangelidou, Anastasia

    2011-01-01

    Dinits-Karzanov-Lomonosov showed that it is possible to encode all minimal edge cuts of a graph by a tree-like structure called a cactus. We show here that minimal edge cuts separating ends of the graph rather than vertices can be `encoded' also by a cactus. We apply our methods to finite graphs as well and we show that several types of cuts can be encoded by cacti.

  18. FPGA-based multi-channel fluorescence lifetime analysis of Fourier multiplexed frequency-sweeping lifetime imaging.

    Science.gov (United States)

    Zhao, Ming; Li, Yu; Peng, Leilei

    2014-09-22

    We report a fast non-iterative lifetime data analysis method for the Fourier multiplexed frequency-sweeping confocal FLIM (Fm-FLIM) system [Opt. Express 22, 10221 (2014)]. The new method, named R-method, allows fast multi-channel lifetime image analysis in the system's FPGA data processing board. Experimental tests proved that the performance of the R-method is equivalent to that of single-exponential iterative fitting, and its sensitivity is well suited for time-lapse FLIM-FRET imaging of live cells, for example cyclic adenosine monophosphate (cAMP) level imaging with GFP-Epac-mCherry sensors. With the R-method and its FPGA implementation, multi-channel lifetime images can now be generated in real time on the multi-channel frequency-sweeping FLIM system, and live readout of FRET sensors can be performed during time-lapse imaging.

  19. [Test and gather data on sweep spike combination tillage tool]. Quarterly technical report, August 1991--March 1992

    Energy Technology Data Exchange (ETDEWEB)

    Lukach, J.

    1992-06-19

    This summary presents the data accumulated to date with only brief comment. It is prepared with the intent that the viewers will offer advice on terminology, data presentation, methods and other. The year end analysis will detail changes in the data due to the tillage treatments. The data is incomplete due to equipment problems and time limitations due to the wet fall and early freeze up. The trial was not completed due to our inability to get the Mikkelsen Chisel Plow Shovel (MCP), a 16 inch sweep with an anhydrous knife, to penetrate untilled land. The MCP shovel penetrated to deep on plowed ground and pulled so hard that the front wheels of our JD4440 tractor were jerked off the ground. The Standard Chisel Plow Shovels (SCP), a 16 inch sweep, worked well and the data is included.

  20. Determination of triazine herbicide residues in water samples by on-line sweeping concentration in micellar electrokinetic chromatography

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A new method for the determination of atrazine, simazine and prometryn in water samples by on-line sweeping concentration technique in micellar electrokinetic chromatography (MEKC) was developed. Various parameters affecting sample enrichment and separation efficiency were systematically studied. Compared with the conventional MEKC method, up to 60-200-fold improve-merit in concentration sensitivity was achieved in terms of peak height by using this sweeping injection technique. The compound strychnine was used as the internal standard for the improvement of the experimental reproducibility. The limits of detection (S/ N = 3:1) for atrazine, simazine and prometryn were 9, 10 and 0.5 ng mL-1, respectively. This method has been successfully applied to the analysis of atrazine, simazine and prometryn in lake, steam and ground water.

  1. NoSWEEP Technology for Wire bonding Applications%引线键合应用中的无偏倒技术

    Institute of Scientific and Technical Information of China (English)

    Hui Wang; Dave DeGrappo

    2003-01-01

    NoSWEEP is a technology to prevent wire sweep and/or sway during molding process. Thistechnology includes unique material, equipment and process to provide cost-effective method which can beeasily implemented on current production process.%无偏倒技术(NoSWEEP)是引线成型工艺过程中防止引线偏倒或偏斜的一种工艺技术.该工艺技术包含独特的材料、设备和工艺,提供了当前生产工艺便于实施的有效方法.

  2. Machining Challenges: Macro to Micro Cutting

    Science.gov (United States)

    Shunmugam, M. S.

    2016-04-01

    Metal cutting is an important machining operation in the manufacture of almost all engineering components. Cutting technology has undergone several changes with the development of machine tools and cutting tools to meet challenges posed by newer materials, complex shapes, product miniaturization and competitive environments. In this paper, challenges in macro and micro cutting are brought out. Conventional and micro end-milling are included as illustrative examples and details are presented along with discussion. Lengthy equations are avoided to the extent possible, as the emphasis is on the basic concepts.

  3. A cutting force model for micromilling applications

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2006-01-01

    In micro milling the maximum uncut chip thickness is often smaller than the cutting edge radius. This paper introduces a new cutting force model for ball nose micro milling that is capable of taking into account the effect of the edge radius.......In micro milling the maximum uncut chip thickness is often smaller than the cutting edge radius. This paper introduces a new cutting force model for ball nose micro milling that is capable of taking into account the effect of the edge radius....

  4. Cutting food in terrestrial carnivores and herbivores.

    Science.gov (United States)

    Sanson, Gordon

    2016-06-06

    Insects and mammals cut their food up into small pieces to facilitate ingestion and chemical digestion. Teeth and jaws act as cutting tools, but, unlike engineering tools designed for a specific purpose, must generally cope with substantial variation in food properties and work at many scales. Knowing how teeth and jaws work effectively requires an understanding of the cutting on the edges and the mechanisms that remove cut material. Variability and heterogeneity of diet properties are not well known, and, for example, may be higher and overlap more in the browsing and grazing categories of plant diets. A reinterpretation of tooth function in large mammal browsers and grazers is proposed.

  5. Underwater laser cutting of metal structures

    Energy Technology Data Exchange (ETDEWEB)

    Alfille, J.P.; Prunele, D. de [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Direction des Technologies Avancees; Pilot, G. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Dept. de Protection de l`Environnement et des Installations; Fredrick, P.; Ramaswami, V.S.; Muys, P. [Radius Engineering, Gent (Belgium)

    1994-12-31

    Cutting tests were carried out on stainless steel (304L) in air and under 7 meters of water (application to reactor pools), using CO{sub 2} and YAG lasers; results concerned cutting speed, quality of cut, cutting thickness. By-products of sectioning operations using a CO{sub 2} laser were studied: dross, aerosols, suspended particles in water, gas analysis, chemical analysis of the aerosols. Same measurements are currently being taken in the case of the YAG laser with beam transported via optical fiber. (from author). 16 figs., 2 tabs., 3 refs.

  6. Extended-bandwidth frequency sweeps of a distributed feedback laser using combined injection current and temperature modulation

    Science.gov (United States)

    Hefferman, Gerald; Chen, Zhen; Wei, Tao

    2017-07-01

    This article details the generation of an extended-bandwidth frequency sweep using a single, communication grade distributed feedback (DFB) laser. The frequency sweep is generated using a two-step technique. In the first step, injection current modulation is employed as a means of varying the output frequency of a DFB laser over a bandwidth of 99.26 GHz. A digital optical phase lock loop is used to lock the frequency sweep speed during current modulation, resulting in a linear frequency chirp. In the second step, the temperature of the DFB laser is modulated, resulting in a shifted starting laser output frequency. A laser frequency chirp is again generated beginning at this shifted starting frequency, resulting in a frequency-shifted spectrum relative to the first recorded data. This process is then repeated across a range of starting temperatures, resulting in a series of partially overlapping, frequency-shifted spectra. These spectra are then aligned using cross-correlation and combined using averaging to form a single, broadband spectrum with a total bandwidth of 510.9 GHz. In order to investigate the utility of this technique, experimental testing was performed in which the approach was used as the swept-frequency source of a coherent optical frequency domain reflectometry system. This system was used to interrogate an optical fiber containing a 20 point, 1-mm pitch length fiber Bragg grating, corresponding to a period of 100 GHz. Using this technique, both the periodicity of the grating in the frequency domain and the individual reflector elements of the structure in the time domain were resolved, demonstrating the technique's potential as a method of extending the sweeping bandwidth of semiconductor lasers for frequency-based sensing applications.

  7. EQUATIONS OF RADIATION TRANSFER IN INFRARED TOMOGRAPHY IN THE CASE OF ACTIVE-PASSIVE DIAGNOSIS AND SWEEPING SCANNING

    Directory of Open Access Journals (Sweden)

    A. A. Makarova

    2014-01-01

    Full Text Available Sweeping scanning scheme of a hot gas in the task of infrared tomography is formulated. Two diagnosis regimes are used: the active one (ON – with included source and the passive one (OFF – without it. Two integral equations are deduced concerning the absorption coefficient k and the Planck function B of a medium (by which it is possible to calculate the temperature profile of a medium T.

  8. A Method on Non-Linear Correction of Broadband LFMCW Signal Utilizing Its Relative Sweep Non-Linear Error

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper presents a method on non-linear correction of broadband LFMCW signal utilizing its relativenonlinear error. The deriving procedure and the results simulated by a computer and tested by a practical system arealso introduced. The method has two obvious advantages compared with the previous methods: (1) Correction has norelation with delay time td and sweep bandwidth B; (2) The inherent non-linear error of VCO has no influence on thecorrection and its last results.

  9. Cutting Properties of Austenitic Stainless Steel by Using Laser Cutting Process without Assist Gas

    Directory of Open Access Journals (Sweden)

    Hitoshi Ozaki

    2012-01-01

    Full Text Available Recently, laser cutting is used in many industries. Generally, in laser cutting of metallic materials, suitable assist gas and its nozzle are needed to remove the molten metal. However, because of the gas nozzle should be set closer to the surface of a workpiece, existence of the nozzle seems to prevent laser cutting from being used flexible. Therefore, the new cutting process, Assist Gas Free laser cutting or AGF laser cutting, has been developed. In this process, the pressure at the bottom side of a workpiece is reduced by a vacuum pump, and the molten metal can be removed by the air flow caused by the pressure difference between both sides of the specimen. In this study, cutting properties of austenitic stainless steel by using AGF laser cutting with 2 kW CO2 laser were investigated. Laser power and cutting speed were varied in order to study the effect of these parameters on cutting properties. As a result, austenitic stainless steel could be cut with dross-free by AGF laser cutting. When laser power was 2.0 kW, cutting speed could be increased up to 100 mm/s, and kerf width at specimen surface was 0.28 mm.

  10. Strong Selective Sweeps on the X Chromosome in the Human-Chimpanzee Ancestor Explain Its Low Divergence.

    Directory of Open Access Journals (Sweden)

    Julien Y Dutheil

    2015-08-01

    Full Text Available The human and chimpanzee X chromosomes are less divergent than expected based on autosomal divergence. We study incomplete lineage sorting patterns between humans, chimpanzees and gorillas to show that this low divergence can be entirely explained by megabase-sized regions comprising one-third of the X chromosome, where polymorphism in the human-chimpanzee ancestral species was severely reduced. We show that background selection can explain at most 10% of this reduction of diversity in the ancestor. Instead, we show that several strong selective sweeps in the ancestral species can explain it. We also report evidence of population specific sweeps in extant humans that overlap the regions of low diversity in the ancestral species. These regions further correspond to chromosomal sections shown to be devoid of Neanderthal introgression into modern humans. This suggests that the same X-linked regions that undergo selective sweeps are among the first to form reproductive barriers between diverging species. We hypothesize that meiotic drive is the underlying mechanism causing these two observations.

  11. Linear sweep voltammetric studies on the supramolecular complex of alizarin red S with lysozyme and determination of lysozyme

    Indian Academy of Sciences (India)

    Wei Sun; Na Zhao; Xueliang Niu; Yan Wang; Kui Jiao

    2009-03-01

    An electrochemical method for the determination of lysozyme (LYS) based on its interaction with alizarin red S (ARS) was established by linear sweep voltammetry in this paper. The electrochemical behaviour of ARS with LYS was investigated on a dropping mercury working electrode in 0.2 mol/L pH 4.8 Britton-Robinson (B-R) buffer solution. ARS showed a sensitive second order derivative linear sweep voltammetric reductive peak at -0.42 V (vs SCE). After the addition of LYS, the reductive peak current of ARS decreased without the shift of the reductive peak potential and no new waves appeared, which was due to the formation of a supramolecular complex of ARS with LYS in the solution. The stoichiometry of the ARS-LYS complex was further calculated by the electrochemical data with the results of the binding ratio as 3 : 1 and the binding constant as 2.82 × 1014. Under the selected conditions, the decrease of the second order derivative linear sweep voltammetric reductive peak current of ARS was in proportion to the LYS concentration in the range from 0.8 to 35.0 mg/L and the detection limit of LYS was calculated as 0.52 mg/L (3). Different kinds of LYS samples were detected satisfactorily with this method.

  12. Improving the sweeping efficiency of permanganate into low permeable zones to treat TCE: experimental results and model development.

    Science.gov (United States)

    Chokejaroenrat, Chanat; Kananizadeh, Negin; Sakulthaew, Chainarong; Comfort, Steve; Li, Yusong

    2013-11-19

    The residual buildup and treatment of dissolved contaminants in low permeable zones (LPZs) is a particularly challenging issue for injection-based remedial treatments. Our objective was to improve the sweeping efficiency of permanganate into LPZs to treat dissolved-phase TCE. This was accomplished by conducting transport experiments that quantified the ability of xanthan-MnO4(-) solutions to penetrate and cover (i.e., sweep) an LPZ that was surrounded by transmissive sands. By incorporating the non-Newtonian fluid xanthan with MnO4(-), penetration of MnO4(-) into the LPZ improved dramatically and sweeping efficiency reached 100% in fewer pore volumes. To quantify how xanthan improved TCE removal, we spiked the LPZ and surrounding sands with (14)C-lableled TCE and used a multistep flooding procedure that quantified the mass of (14)C-TCE oxidized and bypassed during treatment. Results showed that TCE mass removal was 1.4 times greater in experiments where xanthan was employed. Combining xanthan with MnO4(-) also reduced the mass of TCE in the LPZ that was potentially available for rebound. By coupling a multiple species reactive transport model with the Brinkman equation for non-Newtonian flow, the simulated amount of (14)C-TCE oxidized during transport matched experimental results. These observations support the use of xanthan as a means of enhancing MnO4(-) delivery into LPZs for the treatment of dissolved-phase TCE.

  13. Effect of ohmic, mass-transfer, and kinetic resistances on linear-sweep voltammetry in a cylindrical-pore electrode

    Science.gov (United States)

    Weidner, John W.; Fedkiw, Peter S.

    1991-01-01

    A means is presented to account for the effect of ohmic, mass-transfer, and kinetic resistances on linear-sweep voltammograms by modeling a pore in a porous matrix as a cylindrical-pore electrode, and solving the mass and charge conservation equations in the context of this geometry for the simply redox reaction O + ne(-) yield R where both O and R are soluble species. Both analytical and numerical techniques are used to solve the governing equations. The calculated peak currents and potentials are correlated by empirical formulas to the measurable parameters: sweep rate, concentration of the redox species, diffusion coefficient, conductivity of the electrolyte, and pore dimensions. Using the correlations, a methodology is established for determining if the redox reaction kinetics are irreversible or reversible (Nernstian). If the reaction is irreversible, it is shown how the standard rate constant and the transfer coefficient may be extracted from linear-sweep voltammetry data, or, if the reaction is reversible, how the number of electrons transferred may be deduced.

  14. Influence of high-conductivity buffer composition on field-enhanced sample injection coupled to sweeping in CE.

    Science.gov (United States)

    Anres, Philippe; Delaunay, Nathalie; Vial, Jérôme; Thormann, Wolfgang; Gareil, Pierre

    2013-02-01

    The aim of this work was to clarify the mechanism taking place in field-enhanced sample injection coupled to sweeping and micellar EKC (FESI-Sweep-MEKC), with the utilization of two acidic high-conductivity buffers (HCBs), phosphoric acid or sodium phosphate buffer, in view of maximizing sensitivity enhancements. Using cationic model compounds in acidic media, a chemometric approach and simulations with SIMUL5 were implemented. Experimental design first enabled to identify the significant factors and their potential interactions. Simulation demonstrates the formation of moving boundaries during sample injection, which originate at the initial sample/HCB and HCB/buffer discontinuities and gradually change the compositions of HCB and BGE. With sodium phosphate buffer, the HCB conductivity increased during the injection, leading to a more efficient preconcentration by staking (about 1.6 times) than with phosphoric acid alone, for which conductivity decreased during injection. For the same injection time at constant voltage, however, a lower amount of analytes was injected with sodium phosphate buffer than with phosphoric acid. Consequently sensitivity enhancements were lower for the whole FESI-Sweep-MEKC process. This is why, in order to maximize sensitivity enhancements, it is proposed to work with sodium phosphate buffer as HCB and to use constant current during sample injection. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Interactions between oxygen permeation and homogeneous-phase fuel conversion on the sweep side of an ion transport membrane

    KAUST Repository

    Hong, Jongsup

    2013-02-01

    The interactions between oxygen permeation and homogeneous fuel oxidation reactions on the sweep side of an ion transport membrane (ITM) are examined using a comprehensive model, which couples the dependency of the oxygen permeation rate on the membrane surface conditions and detailed chemistry and transport in the vicinity of the membrane. We assume that the membrane surface is not catalytic to hydrocarbon or syngas oxidation. Results show that increasing the sweep gas inlet temperature and fuel concentration enhances oxygen permeation substantially. This is accomplished through promoting oxidation reactions (oxygen consumption) and the transport of the products and reaction heat towards the membrane, which lowers the oxygen concentration and increases the gas temperature near the membrane. Faster reactions at higher fuel concentration and higher inlet gas temperature support substantial fuel conversion and lead to a higher oxygen permeation flux without the contribution of surface catalytic activity. Beyond a certain maximum in the fuel concentration, extensive heat loss to the membrane (and feed side) reduces the oxidation kinetic rates and limits oxygen permeation as the reaction front reaches the membrane. The sweep gas flow rate and channel height have moderate impacts on oxygen permeation and fuel conversion due to the residence time requirements for the chemical reactions and the location of the reaction zone relative to the membrane surface. © 2012 Elsevier B.V.

  16. Segmentation of knee joints in x-ray images using decomposition-based sweeping and graph search

    Science.gov (United States)

    Mu, Jian; Liu, Xiaomin; Luan, Shuang; Heintz, Philip H.; Mlady, Gary W.; Chen, Danny Z.

    2011-03-01

    Plain radiography (i.e., X-ray imaging) provides an effective and economical imaging modality for diagnosing knee illnesses and injuries. Automatically segmenting and analyzing knee radiographs is a challenging problem. In this paper, we present a new approach for accurately segmenting the knee joint in X-ray images. We first use the Gaussian high-pass filter to remove homogeneous regions which are unlikely to appear on bone contours. We then presegment the bones and develop a novel decomposition-based sweeping algorithm for extracting bone contour topology from the filtered skeletonized images. Our sweeping algorithm decomposes the bone structures into several relatively simple components and deals with each component separately based on its geometric characteristics using a sweeping strategy. Utilizing the presegmentation, we construct a graph to model the bone topology and apply an optimal graph search algorithm to optimize the segmentation results (with respect to our cost function defined on the bone boundaries). Our segmented results match well with the manual tracing results by radiologists. Our segmentation approach can be a valuable tool for assisting radiologists and X-ray technologists in clinical practice and training.

  17. Variable Sweep Transition Flight Experiment (VSTFE)-Parametric Pressure Distribution Boundary Layer Stability Study and Wing Glove Design Task

    Science.gov (United States)

    Rozendaal, Rodger A.

    1986-01-01

    The Variable Sweep Transition Flight Experiment (VSTFE) was initiated to establish a boundary-layer transition data base for laminar flow wing design. For this experiment, full-span upper-surface gloves will be fitted to a variable sweep F-14 aircraft. The results of two initial tasks are documented: a parametric pressure distribution/boundary-layer stability study and the design of an upper-surface glove for Mach 0.8. The first task was conducted to provide a data base from which wing-glove pressure distributions could be selected for glove designs. Boundary-layer stability analyses were conducted on a set of pressure distributions for various wing sweep angles, Mach numbers, and Reynolds number in the range of those anticipated for the flight-test program. The design procedure for the Mach 0.8 glove is described, and boundary-layer stability calculations and pressure distributions are presented both at design and off-design conditions. Also included is the analysis of the clean-up glove (smoothed basic wing) that will be flight-tested initially and the analysis of a Mach 0.7 glove designed at the NASA Langley Research Center.

  18. (1)H-(2)H cross-polarization NMR in fast spinning solids by adiabatic sweeps.

    Science.gov (United States)

    Wi, Sungsool; Schurko, Robert; Frydman, Lucio

    2017-03-14

    Cross-polarization (CP) experiments employing frequency-swept radiofrequency (rf) pulses have been successfully used in static spin systems for obtaining broadband signal enhancements. These experiments have been recently extended to heteronuclear I, S = spin-1/2 nuclides under magic-angle spinning (MAS), by applying adiabatic inversion pulses along the S (low-γ) channel while simultaneously applying a conventional spin-locking pulse on the I-channel ((1)H). This study explores an extension of this adiabatic frequency sweep concept to quadrupolar nuclei, focusing on CP from (1)H (I = 1/2) to (2)H spins (S = 1) undergoing fast MAS (νr = 60 kHz). A number of new features emerge, including zero- and double-quantum polarization transfer phenomena that depend on the frequency offsets of the swept pulses, the rf pulse powers, and the MAS spinning rate. An additional mechanism found operational in the (1)H-(2)H CP case that was absent in the spin-1/2 counterpart, concerns the onset of a pseudo-static zero-quantum CP mode, driven by a quadrupole-modulated rf/dipolar recoupling term arising under the action of MAS. The best CP conditions found at these fast spinning rates correspond to double-quantum transfers, involving weak (2)H rf field strengths. At these easily attainable (ca. 10 kHz) rf field conditions, adiabatic level-crossings among the {|1⟩,|0⟩,|-1⟩} mS energy levels, which are known to complicate the CP MAS of quadrupolar nuclei, are avoided. Moreover, the CP line shapes generated in this manner are very close to the ideal (2)H MAS spectral line shapes, facilitating the extraction of quadrupolar coupling parameters. All these features were corroborated with experiments on model compounds and justified using numerical simulations and average Hamiltonian theory models. Potential applications of these new phenomena, as well as extensions to higher spins S, are briefly discussed.

  19. Diversity and selective sweep in the OsAMT1;1 genomic region of rice

    Directory of Open Access Journals (Sweden)

    Chen Sheng

    2011-03-01

    Full Text Available Abstract Background Ammonium is one of the major forms in which nitrogen is available for plant growth. OsAMT1;1 is a high-affinity ammonium transporter in rice (Oryza sativa L., responsible for ammonium uptake at low nitrogen concentration. The expression pattern of the gene has been reported. However, variations in its nucleotides and the evolutionary pathway of its descent from wild progenitors are yet to be elucidated. In this study, nucleotide diversity of the gene OsAMT1;1 and the diversity pattern of seven gene fragments spanning a genomic region approximately 150 kb long surrounding the gene were surveyed by sequencing a panel of 216 rice accessions including both cultivated rice and wild relatives. Results Nucleotide polymorphism (Pi of OsAMT1;1 was as low as 0.00004 in cultivated rice (Oryza sativa, only 2.3% of that in the common wild rice (O. rufipogon. A single dominant haplotype was fixed at the locus in O. sativa. The test values for neutrality were significantly negative in the entire region stretching 5' upstream and 3' downstream of the gene in all accessions. The value of linkage disequilibrium remained high across a 100 kb genomic region around OsAMT1;1 in O. sativa, but fell rapidly in O. rufipogon on either side of the promoter of OsAMT1;1, demonstrating a strong natural selection within or nearby the ammonium transporter. Conclusions The severe reduction in nucleotide variation at OsAMT1;1 in rice was caused by a selective sweep around OsAMT1;1, which may reflect the nitrogen uptake system under strong selection by the paddy soil during the domestication of rice. Purifying selection also occurred before the wild rice diverged into its two subspecies, namely indica and japonica. These findings would provide useful insights into the processes of evolution and domestication of nitrogen uptake genes in rice.

  20. A selective sweep in a Varroa destructor resistant honeybee (Apis mellifera) population.

    Science.gov (United States)

    Lattorff, H Michael G; Buchholz, Josephine; Fries, Ingemar; Moritz, Robin F A

    2015-04-01

    The mite Varroa destructor is one of the most dangerous parasites of the Western honeybee (Apis mellifera) causing enormous colony losses worldwide. Various chemical treatments for the control of the Varroa mite are currently in use, which, however, lead to residues in bee products and often to resistance in mites. This facilitated the exploration of alternative treatment methods and breeding for mite resistant honeybees has been in focus for breeders in many parts of the world with variable results. Another approach has been applied to a honeybee population on Gotland (Sweden) that was exposed to natural selection and survived Varroa-infestation for more than 10years without treatment. Eventually this population became resistant to the parasite by suppressing the reproduction of the mite. A previous QTL mapping study had identified a region on chromosome 7 with major loci contributing to the mite resistance. Here, a microsatellite scan of the significant candidate QTL regions was used to investigate potential footprints of selection in the original population by comparing the study population on Gotland before (2000) and after selection (2007). Genetic drift had caused an extreme loss of genetic diversity in the 2007 population for all genetic markers tested. In addition to this overall reduction of heterozygosity, two loci on chromosome 7 showed an even stronger and significant reduction in diversity than expected from genetic drift alone. Within the selective sweep eleven genes are annotated, one of them being a putative candidate to interfere with reduced mite reproduction. A glucose-methanol-choline oxidoreductase (GMCOX18) might be involved in changing volatiles emitted by bee larvae that might be essential to trigger oogenesis in Varroa.

  1. Laser cutting of triangular geometries in aluminum foam: Effect of cut size on thermal stress levels

    Science.gov (United States)

    Yilbas, B. S.; Akhtar, S. S.; Keles, O.

    2013-06-01

    Laser cutting of triangle shaped geometries in aluminum foam is carried out and the influence of triangle size on temperature and stress fields is examined. ABAQUS finite element code is used to simulate temperature and stress fields in the cut sections in line with the experimental conditions. Laser cut sections are examined incorporating optical and scanning electron microscopes, and energy dispersive spectroscopy. It is found that small size triangle cut results in relatively higher temperatures around the cut edges as compared to large size triangle cut; however, opposite is true for von Mises stress. This is attributed to the slow cooling rate in the case of the small size triangle cuts. Laser cut surfaces are free from large defects and locally scattered small dross attachment are found at the kerf exit.

  2. Selection of Near Optimal Laser Cutting Parameters in CO2 Laser Cutting by the Taguchi Method

    Directory of Open Access Journals (Sweden)

    Miloš MADIĆ

    2013-12-01

    Full Text Available Identification of laser cutting conditions that are insensitive to parameter variations and noise is of great importance. This paper demonstrates the application of Taguchi method for optimization of surface roughness in CO2 laser cutting of stainless steel. The laser cutting experiment was planned and conducted according to the Taguchi’s experimental design using the L27 orthogonal array. Four laser cutting parameters such as laser power, cutting speed, assist gas pressure, and focus position were considered in the experiment. Using the analysis of means and analysis of variance, the significant laser cutting parameters were identified, and subsequently the optimal combination of laser cutting parameter levels was determined. The results showed that the cutting speed is the most significant parameter affecting the surface roughness whereas the influence of the assist gas pressure can be neglected. It was observed, however, that interaction effects have predominant influence over the main effects on the surface roughness.

  3. Experimental research on the durability cutting tools for cutting-off steel profiles

    Directory of Open Access Journals (Sweden)

    Cristea Alexandru

    2017-01-01

    Full Text Available The production lines used for manufacturing U-shaped profiles are very complex and they must have high productivity. One of the most important stages of the fabrication process is the cutting-off. This paper presents the experimental research and analysis of the durability of the cutting tools used for cutting-off U-shaped metal steel profiles. The results of this work can be used to predict the durability of the cutting tools.

  4. On the influence of the nozzle length on the arc properties in a cutting torch

    Energy Technology Data Exchange (ETDEWEB)

    Prevosto, L; Risso, M; Infante, D [Grupo de Descargas Electricas, Departamento Ingenieria Electromecanica, Universidad Tecnologica Nacional, Regional Venado Tuerto, Las Heras 644, Venado Tuerto (2600), Santa Fe (Argentina); Kelly, H, E-mail: prevosto@waycom.com.a [Instituto de FIsica del Plasma (CONICET), Departamento de Fisica, Facultad de Ciencias Exactas y Naturales (UBA) Ciudad Universitaria Pab. I, 1428 Buenos Aires (Argentina)

    2009-05-01

    In this work, an experimental study on the influence of the nozzle geometry on the physical properties of a cutting arc is reported. Ion current signals collected by an electrostatic probe sweeping across a 30 A oxygen cutting arc at 3.5 mm from the nozzle exit were registered for different nozzle lengths. The temperature and density radial profiles of the arc plasma were found in each case by an inversion procedure of these signals. A comparison between the obtained results shows that the shorter nozzle (R{sub N} = 0.50 mm, L{sub N} = 4.5 mm operated at 0.7 MPa and 35 Nl/min) produces a thinner and hotter arc than the larger nozzle (R{sub N} = 0.50 mm, L{sub N} = 9.0 mm operated at 1.1 MPa and 20 Nl/min). This behavior is attributed to the marked difference of gas flow rate due to the clogging effect. A smaller gas mass flow reduces the convective cooling at the arc border and decreases the power dissipation of the arc column, resulting in small axis temperatures.

  5. Combustion systems and power plants incorporating parallel carbon dioxide capture and sweep-based membrane separation units to remove carbon dioxide from combustion gases

    Science.gov (United States)

    Wijmans, Johannes G.; Merkel, Timothy C; Baker, Richard W.

    2011-10-11

    Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbon dioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.

  6. Determination of lysergic acid diethylamide (LSD) in mouse blood by capillary electrophoresis/ fluorescence spectroscopy with sweeping techniques in micellar electrokinetic chromatography.

    Science.gov (United States)

    Fang, Ching; Liu, Ju-Tsung; Chou, Shiu-Huey; Lin, Cheng-Huang

    2003-03-01

    The separation and on-line concentration of lysergic acid diethylamide (LSD) in mouse blood was achieved by means of capillary electrophoresis/fluorescence spectroscopy using sodium dodecyl sulfate (SDS) as the surfactant. Techniques involving on-line sample concentration, including sweeping micellar electrokinetic chromatography (sweeping-MEKC) and cation-selective exhaustive injection-sweep-micellar electrokinetic chromatography (CSEI-sweep-MEKC) were applied; the optimum on-line concentration and separation conditions were determined. In the analysis of an actual sample, LSD was found in a blood sample from a test mouse (0.1 mg LSD fed to a 20 g mouse; approximately 1/10 to the value of LD(50)). As a result, 120 and 30 ng/mL of LSD was detected at 20 and 60 min, respectively, after ingestion of the doses.

  7. Determination of lysergic acid diethylamide (LSD) by application of online 77 K fluorescence spectroscopy and a sweeping technique in micellar electrokinetic chromatography.

    Science.gov (United States)

    Fang, Ching; Liu, Ju-Tsung; Lin, Cheng-Huang

    2002-10-16

    The principal advantage of the use of Shopl'skii effect (low temperature spectrum) is that spectral sharpening occurs both in absorption and emission. However, thus far using the technique of capillary electrophoresis/low temperature fluorescence spectroscopy (CE/LTFS) either at 77 or 4.2 K remains difficult to obtain an on-line spectrum, if the analyte is present at low concentration. This paper examines the feasibility of combining the techniques of online concentration and CE/LTFS to identify LSD and related compounds in urine at 77 K. To improve sensitivity, sweeping-micellar electrokinetic chromatography (sweeping-MEKC) and cation-selective exhaustive injection-sweep-micellar electrokinetic chromatography (CSEI-sweep-MEKC) were used for on-line concentration which resulted in detection limits of approximately 20 approximately 60 ppt, respectively.

  8. Quarter-sweep Gauss-Seidel method with quadratic spline scheme applied to fourth order two-point boundary value problems

    Science.gov (United States)

    Mohd Fauzi, Norizyan Izzati; Sulaiman, Jumat

    2013-04-01

    The aim of this paper is to describe the application of Quarter-Sweep Gauss-Seidel (QSGS) iterative method using quadratic spline scheme for solving fourth order two-point linear boundary value problems. In the line to derive approximation equations, firstly the fourth order problems need to be reduced onto a system of second-order two-point boundary value problems. Then two linear systems have been constructed via discretization process by using the corresponding quarter-sweep quadratic spline approximation equations. The generated linear systems have been solved using the proposed QSGS iterative method to show the superiority over Full-Sweep Gauss-Seidel (FSGS) and Half-Sweep Gauss-Seidel (HSGS) methods. Computational results are provided to illustrate that the effectiveness of the proposed QSGS method is more superior in terms of computational time and number of iterations as compared to other tested methods.

  9. Postharvest: Cut flowers and potted plants

    Science.gov (United States)

    In the past fifty years, the cut flower market has changed dramatically, from a local market with growers located on city outskirts, to a global one; flowers and cut foliage sourced from throughout the world are sold as bunches or combined into arrangements and bouquets in the major target markets. ...

  10. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is generate

  11. Experimental analysis of cut welding in aluminium

    DEFF Research Database (Denmark)

    Dorph, Pernille; De Chiffre, Leonardo; Bay, Niels

    1993-01-01

    Cut welding is a newly developed cold pressure welding process. In the present work, an experimental investigation was carried out analyzing the mechanisms involved in cut welding of a block to a strip. Experiments were carried out in technically pure aluminium. The investigation has involved...

  12. Designing for hot-blade cutting

    DEFF Research Database (Denmark)

    Brander, David; Bærentzen, Jakob Andreas; Clausen, Kenn

    2016-01-01

    -trivial constraints of blade-cutting in a bottom-up fashion, enabling an exploration of the unique architectural potential of this fabrication approach. The method is implemented as prototype design tools in MatLAB, C++, GhPython, and Python and demonstrated through cutting of expanded polystyrene foam design...

  13. Drilling subsurface wellbores with cutting structures

    Science.gov (United States)

    Mansure, Arthur James; Guimerans, Rosalvina Ramona

    2010-11-30

    A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

  14. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is

  15. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is generate

  16. Laser cutting - trends in the development,

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2002-01-01

    Since the laser was invented in 1960, the industrial applications of this tool has grown and grown. And - since the beginning of the 1980'ies, the major industrial application of lasers in production has been laser cutting. In this paper a short review of the development of the laser cutting...

  17. Gluebond strength of laser cut wood

    Science.gov (United States)

    Charles W. McMillin; Henry A. Huber

    1985-01-01

    The degree of strength loss when gluing laser cut wood as compared to conventionally sawn wood and the amount of additional surface treatment needed to improve bond quality were assessed under normal furniture plant operating conditions. The strength of laser cut oak glued with polyvinyl acetate adhesive was reduced to 75 percent of sawn joints and gum was reduced 43...

  18. Laser cutting - trends in the development,

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove

    2002-01-01

    Since the laser was invented in 1960, the industrial applications of this tool has grown and grown. And - since the beginning of the 1980'ies, the major industrial application of lasers in production has been laser cutting. In this paper a short review of the development of the laser cutting...

  19. 33 CFR 117.143 - Bishop Cut.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bishop Cut. 117.143 Section 117... OPERATION REGULATIONS Specific Requirements California § 117.143 Bishop Cut. The draw of the San Joaquin County highway bridge, mile 1.0 between King Island and Bishop Tract, shall open on signal if at least...

  20. Cutting Watermelon: Lessons in Instructional Coaching

    Science.gov (United States)

    Sandstead, Martha

    2016-01-01

    Literacy coordinator Martha Sandstead finds inspiration for her coaching work in a quote from civil rights organizer Lawrence Guyot: "Let's say you're riding past a picnic, and people are cuttin' watermelons. You don't immediately go and say, "stop the watermelon cutting" and let's talk. … You cut some watermelons, or you help…

  1. Cutting tool form compensation system and method

    Science.gov (United States)

    Barkman, W.E.; Babelay, E.F. Jr.; Klages, E.J.

    1993-10-19

    A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed. 9 figures.

  2. Cutting tool form compensaton system and method

    Science.gov (United States)

    Barkman, William E.; Babelay, Jr., Edwin F.; Klages, Edward J.

    1993-01-01

    A compensation system for a computer-controlled machining apparatus having a controller and including a cutting tool and a workpiece holder which are movable relative to one another along a preprogrammed path during a machining operation utilizes a camera and a vision computer for gathering information at a preselected stage of a machining operation relating to the actual shape and size of the cutting edge of the cutting tool and for altering the preprogrammed path in accordance with detected variations between the actual size and shape of the cutting edge and an assumed size and shape of the cutting edge. The camera obtains an image of the cutting tool against a background so that the cutting tool and background possess contrasting light intensities, and the vision computer utilizes the contrasting light intensities of the image to locate points therein which correspond to points along the actual cutting edge. Following a series of computations involving the determining of a tool center from the points identified along the tool edge, the results of the computations are fed to the controller where the preprogrammed path is altered as aforedescribed.

  3. Bun splitting: a practical cutting stock problem

    NARCIS (Netherlands)

    C.A. Glass (Catherine); J.M. van Oostrum (Jeroen)

    2010-01-01

    textabstractWe describe a new hierarchical 2D-guillotine Cutting Stock Problem. In contrast to the classic cutting stock problem, waste is not an issue. The problem relates to the removal of a defective part and assembly of the remaining parts into homogeneous size blocks. The context is the packing

  4. Cutting Watermelon: Lessons in Instructional Coaching

    Science.gov (United States)

    Sandstead, Martha

    2016-01-01

    Literacy coordinator Martha Sandstead finds inspiration for her coaching work in a quote from civil rights organizer Lawrence Guyot: "Let's say you're riding past a picnic, and people are cuttin' watermelons. You don't immediately go and say, "stop the watermelon cutting" and let's talk. … You cut some watermelons, or you help…

  5. Thermophysical problems of laser cutting of metals

    Directory of Open Access Journals (Sweden)

    Orishich Anatoliy

    2017-01-01

    Full Text Available Variety and complex interaction of physical processes during laser cutting is a critical characteristic of the laser cutting of metals. Small spatial and temporal scales complicate significantly the experimental investigations of the multi-phase fluid flow in the conditions of laser cutting of metals. In these conditions, the surface formed during the cutting is an indicator determining the melt flow character. The quantitative parameter reflecting the peculiarities of the multi-phase fluid flow, is normally the roughness of the forming surface, and the minimal roughness is the criterion of the qualitative flow [1 – 2]. The purpose of this work is to perform the experimental comparative investigation of the thermophysical pattern of the multi-phase melt flow in the conditions of the laser cutting of metals with the laser wavelength of 10.6 μm and 1.07 μm.

  6. Cutting as a continuous business process

    Directory of Open Access Journals (Sweden)

    Miro Gradišar

    2009-11-01

    Full Text Available A review of state-of-the-art methods for cutting stock problem optimisation shows that the current methods lead to near-optimum results for the instantaneous optimisation of trim loss. Further optimisation of this activity would not bring a considerable improvement. Therefore, the paper treats cutting stock as a continuous business process and not as an isolated activity. An exact method for a general one-dimensional cutting stock problem is presented and tested. The method is mainly suitable for smaller orders. It is then applied to continuous cutting and used to develop a method for assessing cutting costs in consecutive time periods. The modified method finds a good solution over the whole time-span, rather than just local optima.

  7. Corn stalk orientation effect on mechanical cutting

    Energy Technology Data Exchange (ETDEWEB)

    Igathinathane, C. [Mississippi State University (MSU); Womac, A.R. [University of Tennessee; Sokhansanj, Shahabaddine [ORNL

    2010-07-01

    Research efforts that increase the efficiency of size reduction of biomass can lead to a significant energy saving. This paper deals with the determination of the effect of sample orientation with respect to cutting element and quantify the possible cutting energy reduction, utilising dry corn stalks as the test material (15%e20% wet basis). To evaluate the mechanical cutting characteristics of corn stalks, a Warnere Bratzler device was modified by replacing its blunt edged cutting element with one having a 30_ single bevel sharp knife edge. Cutting force-deformation characteristics obtained with a universal testing machine were analysed to evaluate the orientation effects at perpendicular (90o), inclined (45o), and parallel (0o) orientations on internodes and nodes for cutting force, energy, ultimate stress, and specific energy of corn stalks. The corn stalks cutting force-displacement characteristics were found to differ with orientation, and internode and node material difference. Overall, the peak failure force, and the total cutting energy of internodes and nodes varied significantly (P < 0.05) with stalk cross-sectional area. The specific energy values (total energy per unit cut area) of dry corn stalk internodes ranged from 11.3 to 23.5 kN m_1, and nodes from 8.6 to 14.0 kN m_1. The parallel orientation (along grain) compared to perpendicular (across grain) produced a significant reduction of the cutting stress and the specific energy to one tenth or better for internodes, and to about one-fifth for nodes.

  8. Changing cultural attitudes towards female genital cutting.

    Science.gov (United States)

    Vogt, Sonja; Mohmmed Zaid, Nadia Ahmed; El Fadil Ahmed, Hilal; Fehr, Ernst; Efferson, Charles

    2016-10-27

    As globalization brings people with incompatible attitudes into contact, cultural conflicts inevitably arise. Little is known about how to mitigate conflict and about how the conflicts that occur can shape the cultural evolution of the groups involved. Female genital cutting is a prominent example. Governments and international agencies have promoted the abandonment of cutting for decades, but the practice remains widespread with associated health risks for millions of girls and women. In their efforts to end cutting, international agents have often adopted the view that cutting is locally pervasive and entrenched. This implies the need to introduce values and expectations from outside the local culture. Members of the target society may view such interventions as unwelcome intrusions, and campaigns promoting abandonment have sometimes led to backlash as they struggle to reconcile cultural tolerance with the conviction that cutting violates universal human rights. Cutting, however, is not necessarily locally pervasive and entrenched. We designed experiments on cultural change that exploited the existence of conflicting attitudes within cutting societies. We produced four entertaining movies that served as experimental treatments in two experiments in Sudan, and we developed an implicit association test to unobtrusively measure attitudes about cutting. The movies depart from the view that cutting is locally pervasive by dramatizing members of an extended family as they confront each other with divergent views about whether the family should continue cutting. The movies significantly improved attitudes towards girls who remain uncut, with one in particular having a relatively persistent effect. These results show that using entertainment to dramatize locally discordant views can provide a basis for applied cultural evolution without accentuating intercultural divisions.

  9. Laser cutting of Kevlar laminates and thermal stress formed at cutting sections

    Science.gov (United States)

    Yilbas, B. S.; Akhtar, S. S.

    2012-02-01

    Laser cutting of Kevlar laminates is carried out and thermal stress field developed in the cutting region is predicted using the finite element code. Temperature predictions are validated through the thermocouple data. The morphological changes in the cutting section are examined by incorporating optical and scanning electron microscopes. It is found that temperature predictions agree well with the thermocouple data. High values of von Mises stress are observed at the cutting edges and at the mid-thickness of the Kevlar laminate due to thermal compression formed in this region. The laser cut edges are free from whiskers; however, striation formation and some small sideways burning is observed at the kerf edges.

  10. Planetesimal formation by sweep-up: how the bouncing barrier can be beneficial to growth

    Science.gov (United States)

    Windmark, F.; Birnstiel, T.; Güttler, C.; Blum, J.; Dullemond, C. P.; Henning, Th.

    2012-04-01

    Context. The formation of planetesimals is often accredited to the collisional sticking of dust grains. The exact process is unknown, as collisions between larger aggregates tend to lead to fragmentation or bouncing rather than sticking. Recent laboratory experiments have however made great progress in the understanding and mapping of the complex physics involved in dust collisions. Aims: We study the possibility of planetesimal formation using the results of the latest laboratory experiments, particularly by including the fragmentation with mass transfer effect, which might lead to growth even at high impact velocities. Methods: We present a new experimentally and physically motivated dust collision model capable of predicting the outcome of a collision between two particles of arbitrary mass and velocity. The new model includes a natural description of cratering and mass transfer, and provides a smooth transition from equal- to different-sized collisions. It is used together with a continuum dust-size evolution code, which is both fast in terms of execution time and able to resolve the dust at all sizes, allowing for all types of interactions to be studied without biases. Results: For the general dust population, we find that bouncing collisions prevent any growth above millimeter-sizes. However, if a small number of cm-sized particles are introduced, for example by either vertical mixing or radial drift, they can act as a catalyst and start to sweep up the smaller particles. At a distance of 3 AU, 100-m-sized bodies are formed on a timescale of 1 Myr. Conclusions: Direct growth of planetesimals might be a possibility thanks to a combination of the bouncing barrier and the fragmentation with mass transfer effect. The bouncing barrier is here even beneficial, as it prevents the growth of too many large particles that would otherwise only fragment among each other, and creates a reservoir of small particles that can be swept up by larger bodies. However, for this

  11. Estimating cutting front temperature difference in disk and CO2 laser beam fusion cutting

    Science.gov (United States)

    Scintilla, L. D.; Tricarico, L.

    2012-07-01

    A three-dimensional, semi-stationary, simplified thermal numerical model was developed. The average cutting front temperature difference in disk and CO2 laser beam fusion cutting of 90MnCrV8 was estimated by computing the conductive power loss. Basing on heat affected zone extension experimentally measured and using an inverse methodology approach, the unknown thermal load on the cutting front during laser cutting was calculated. The accuracy of the numerical power loss estimation was evaluated comparing the results from simulation with the ones from analytical models. A good agreement was found for all the test cases considered in this study. The conduction losses estimation was used for justifying the lower quality of disk laser cuts due to the lower average cut front temperature. This results in the increase of viscosity of molten material and in the subsequent more difficult ejection of the melted material from the cut kerf.

  12. Results of investigations into coal cutting by asymmetric disks

    Energy Technology Data Exchange (ETDEWEB)

    Krauze, K.

    1985-02-01

    Effects are analyzed of design and specifications of asymmetric disk cutters on coal cutting by a shearer loader with disk cutters on helical cutting drums. Effects of disk diameter, wedge angle, cutting depth and chip thickness on cutting resistance were analyzed under operational conditions (a coal seam was cut by asymmetric disk cutters). On the basis of analysis of coal resistance to cutting by asymmetric cutting disks, regression equations were derived which describe coal cutting. Effects of disk parameters and cutting conditions on cutting resistance were determined. Analyses show that replacing radial cutting tools with asymmetric disk cutters would cause an increase in energy consumption of cutting and increase coal resistance to cutting. 1 reference.

  13. Rejuvenated sycamore cuttings for energy plantations

    Energy Technology Data Exchange (ETDEWEB)

    Land, S.B. Jr.; Elam, W.W. [Mississippi State Univ., MS (United States). Dept. of Forestry; Khan, Mohammad [Pakistan Forest Inst., Peshawar (Pakistan). Forestry Research Div.

    1995-12-31

    Rejuvination of mature, progeny tested American sycamore trees is needed to increase rooting success of cuttings for energy plantations. Studies conducted in Mississippi (U.S.A.) indicated that hedging of stock plants and spraying the stock plants with benzyl adenine may rejuvinate the cuttings. Percentages of cuttings with early bud break in one study and with sprouts and roots after nine months in another study were increased. The rooted cuttings grew rapidly like juvenile material and showed no plagiotrophic effects during the first year after transplanting. At the end of that year the dry weight was 2.13 Mg ha{sup -1} (1.2 m x 3.6 m spacing) and was distributed in stems (31%), branches (14%), leaves (24%) and roots (31%). An IBA rooting powder decreased rooting success. Planting cuttings directly in the nursery, rather than first in the greenhouse, increased success when frost was absent. Use of cuttings of greater than 14 m diameter with a node within 2 cm of the base increased success. Clonal differences in frost susceptibility of sprouting cuttings were observed. (author)

  14. New Tool Coatings for Light Metal Cutting

    Institute of Scientific and Technical Information of China (English)

    DaveDoerwald; ThomasKrug; RoelTietema; Wei-MingSim; QuanshunLuo; PapkenHovsepian

    2004-01-01

    New carbon based coatings have been developed for cutting of light metals such as aluminum. These coatings can be used either directly on the tool or as topcoating combined with another hard base coating. Cutting tests show that the coating gives good performance for materials that tend to stick to the cutting tools, such as aluminium alloys, because of the substantial reduction of appearance of the so-called built-up edge (BUE). This results in a longer life time of the tool and smoother surface finish of the cut made in the work-piece material. Especially in dry machining and deep hole drilling this coating performed very well. An overview of the properties and initial cutting results of this coating will be presented. This paper will also present results from recent industrial field tests carried out by a leading European aerospace manufacturer. Cutting forces, BUE formation and surface roughness data will be presented to explain the cutting process during dry machining.

  15. New Tool Coatings for Light Metal Cutting

    Institute of Scientific and Technical Information of China (English)

    Dave Doerwald; Thomas Krug; Roel Tietema; Wei-Ming Sim; Quanshun Luo; Papken Hovsepian

    2004-01-01

    New carbon based coatings have been developed for cutting of light metals such as aluminum. These coatings can be used either directly on the tool or as topcoating combined with another hard base coating. Cutting tests show that the coating gives good performance for materials that tend to stick to the cutting tools, such as aluminium alloys, because of the substantial reduction of appearance of the so-called built-up edge (BUE). This results in a longer life time of the tool and smoother surface finish of the cut made in the work-piece material. Especially in dry machining and deep hole drilling this coating performed very well. An overview of the properties and initial cutting results of this coating will be presented. This paper will also present results from recent industrial field tests carried out by a leading European aerospace manufacturer.Cutting forces, BUE formation and surface roughness data will be presented to explain the cutting process during dry machining.

  16. Laser cutting of sheets for Tailored Blanks

    DEFF Research Database (Denmark)

    Bagger, Claus; Olsen, Flemming Ove

    1999-01-01

    Over the past few years there has been an enormous increase in the use of tailored blanks, especially in the automotive industry. Often the sheets for tailored blanks are shear cut, but results have been reported that the allowable sheet gap distance should not exceed 0.1 mm in order to obtain...... sound welds. Laser cutting the sheets may therefore be an alternative to shear cutting, if the cut kerf squareness can be kept below 0.05 mm.In a number of systematic laboratory experiments the effects of the major process parameters in laser cutting have been investigated. Each cut was quantified...... by the squareness, the surface roughness and the burr height. Mild steel as well as high strength steel with and with out galvanisation with thickness' of 0.7(5) and 1.25 were used.In the tests the difference in cut quality between a 5" and a 7.5" focusing lens were tested and the effect of using pulsed mode laser...

  17. Reachability cuts for the vehicle routing problem with time windows

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    2004-01-01

    This paper introduces a class of cuts, called reachability cuts, for the Vehicle Routing Problem with Time Windows (VRPTW). Reachability cuts are closely related to cuts derived from precedence constraints in the Asymmetric Traveling Salesman Problem with Time Windows and to k-path cuts...

  18. Reachability cuts for the vehicle routing problem with time windows

    DEFF Research Database (Denmark)

    Lysgaard, Jens

    2004-01-01

    This paper introduces a class of cuts, called reachability cuts, for the Vehicle Routing Problem with Time Windows (VRPTW). Reachability cuts are closely related to cuts derived from precedence constraints in the Asymmetric Traveling Salesman Problem with Time Windows and to k-path cuts...

  19. PH Sensitive Polymers for Improving Reservoir Sweep and Conformance Control in Chemical Flooring

    Energy Technology Data Exchange (ETDEWEB)

    Mukul Sharma; Steven Bryant; Chun Huh

    2008-03-31

    There is an increasing opportunity to recover bypassed oil from depleted, mature oilfields in the US. The recovery factor in many reservoirs is low due to inefficient displacement of the oil by injected fluids (typically water). The use of chemical flooding methods to increase recovery efficiencies is severely constrained by the inability of the injected chemicals to contact the bypassed oil. Low sweep efficiencies are the primary cause of low oil recoveries observed in the field in chemical flooding operations even when lab studies indicate high oil recovery efficiency. Any technology that increases the ability of chemical flooding agents to better contact the remaining oil and reduce the amount of water produced in conjunction with the produced oil will have a significant impact on the cost of producing oil domestically in the US. This translates directly into additional economically recoverable reserves, which extends the economic lives of marginal and mature wells. The objective of this research project was to develop a low-cost, pH-triggered polymer for use in IOR processes to improve reservoir sweep efficiency and reservoir conformance in chemical flooding. Rheological measurements made on the polymer solution, clearly show that it has a low viscosity at low pH and exhibits a sudden increase in viscosity (by 2 orders of magnitude or more) at a pH of 3.5 to 4. This implies that the polymer would preferentially flow into zones containing water since the effective permeability to water is highest in these zones. As the pH of the zone increases due to the buffering capacity of the reservoir rock, the polymer solution undergoes a liquid to gel transition causing a sharp increase in the viscosity of the polymer solution in these zones. This allows operationally robust, in-depth conformance treatment of such water bearing zones and better mobility control. The rheological properties of HPAM solutions were measured. These include: steady-shear viscosity and

  20. PH Sensitive Polymers for Improving Reservoir Sweep and Conformance Control in Chemical Flooring

    Energy Technology Data Exchange (ETDEWEB)

    Mukul Sharma; Steven Bryant; Chun Huh

    2008-03-31

    There is an increasing opportunity to recover bypassed oil from depleted, mature oilfields in the US. The recovery factor in many reservoirs is low due to inefficient displacement of the oil by injected fluids (typically water). The use of chemical flooding methods to increase recovery efficiencies is severely constrained by the inability of the injected chemicals to contact the bypassed oil. Low sweep efficiencies are the primary cause of low oil recoveries observed in the field in chemical flooding operations even when lab studies indicate high oil recovery efficiency. Any technology that increases the ability of chemical flooding agents to better contact the remaining oil and reduce the amount of water produced in conjunction with the produced oil will have a significant impact on the cost of producing oil domestically in the US. This translates directly into additional economically recoverable reserves, which extends the economic lives of marginal and mature wells. The objective of this research project was to develop a low-cost, pH-triggered polymer for use in IOR processes to improve reservoir sweep efficiency and reservoir conformance in chemical flooding. Rheological measurements made on the polymer solution, clearly show that it has a low viscosity at low pH and exhibits a sudden increase in viscosity (by 2 orders of magnitude or more) at a pH of 3.5 to 4. This implies that the polymer would preferentially flow into zones containing water since the effective permeability to water is highest in these zones. As the pH of the zone increases due to the buffering capacity of the reservoir rock, the polymer solution undergoes a liquid to gel transition causing a sharp increase in the viscosity of the polymer solution in these zones. This allows operationally robust, in-depth conformance treatment of such water bearing zones and better mobility control. The rheological properties of HPAM solutions were measured. These include: steady-shear viscosity and

  1. Cut elimination in multifocused linear logic

    DEFF Research Database (Denmark)

    Guenot, Nicolas; Brock-Nannestad, Taus

    2015-01-01

    We study cut elimination for a multifocused variant of full linear logic in the sequent calculus. The multifocused normal form of proofs yields problems that do not appear in a standard focused system, related to the constraints in grouping rule instances in focusing phases. We show that cut...... elimination can be performed in a sensible way even though the proof requires some specific lemmas to deal with multifocusing phases, and discuss the difficulties arising with cut elimination when considering normal forms of proofs in linear logic....

  2. Cut elimination in multifocused linear logic

    DEFF Research Database (Denmark)

    Guenot, Nicolas; Brock-Nannestad, Taus

    2015-01-01

    We study cut elimination for a multifocused variant of full linear logic in the sequent calculus. The multifocused normal form of proofs yields problems that do not appear in a standard focused system, related to the constraints in grouping rule instances in focusing phases. We show that cut elim...... elimination can be performed in a sensible way even though the proof requires some specific lemmas to deal with multifocusing phases, and discuss the difficulties arising with cut elimination when considering normal forms of proofs in linear logic....

  3. Reconfigurable manufacturing execution system for pipe cutting

    Science.gov (United States)

    Yin, Y. H.; Xie, J. Y.

    2011-08-01

    This article presents a reconfigurable manufacturing execution system (RMES) filling the gap between enterprise resource planning and resource layer for pipe-cutting production with mass customisation and rapid adaptation to dynamic market, which consists of planning and scheduling layer and executive control layer. Starting from customer's task and process requirements, the cutting trajectories are planned under generalised mathematical model able to reconfigure in accordance with various intersecting types' joint, and all tasks are scheduled by nesting algorithm to maximise the utilisation rate of rough material. This RMES for pipe cutting has been effectively implemented in more than 100 companies.

  4. A discrete element model for soil-sweep interaction in three different soils

    DEFF Research Database (Denmark)

    Chen, Y; Munkholm, Lars Juhl; Nyord, Tavs

    2013-01-01

    Soil–tool interactions are at the centre of many agricultural field operations, including slurry injection. Understanding of soil–tool interaction behaviours (soil cutting forces and soil disturbance) is important for designing high performance injection tools. A discrete element model was develo....... The calibrated model was validated using the soil disturbance characteristics measured in those three soils. The simulations agreed well with the measurements with relative errors below 10% in most cases....... were measured. The measured draught and vertical forces were used in calibrations of the most sensitive model parameter, particle stiffness. The calibrated particle stiffness was 0.75 × 103 N m−1 for the coarse sand, 2.75 × 103 N m−1 for the loamy sand, and 6 × 103 N m−1 for the sandy loam...

  5. Alkyl imidazolium ionic liquid based sweeping-micellar electrokinetic chromatography for simultaneous determination of seven tea catechins in human plasma.

    Science.gov (United States)

    El-Hady, Deia Abd; Albishri, Hassan M

    2014-10-15

    Determination of tea catechins in human plasma might provide a means of better evaluation of their benefits. The main difficulty in their analysis is the low catechins concentrations in plasma and their susceptible to oxidation during sample pretreatment. In the current work, a sweeping-micellar electrokinetic chromatography (sweeping-MEKC) by long alkyl chain ionic liquid was investigated for the simultaneous determination of seven principal naturally-occurring tea catechins in human plasma under acidic conditions after the intake of green tea beverage. The effects of type and concentration of three 1-tetradecyl-3-methylimidazolium ionic liquids, namely bromide, acetate and hydrogen sulfate salts were studied. The seven catechins were successfully separated within 5min by micellar running buffer of 5mmolL(-1) 1-tetradecyl-3-methylimidazolium bromide and 15mmolL(-1) phosphate buffer at pH 4.5 under optimal parameters of 50mbar injection for 150s, 10kV, 25°C and 200nm. To prevent the possibility of IL adsorption, an appropriate rinsing protocol was established. The method has analytical ranges from 0.5, 1, 0.5, 1, 2, 1 and 1 to 500ngmL(-1) for GC, C, EC, EGCG, GCG, ECG and EGC, respectively (r ranged from 0.995 to 0.999). The intraday precision and accuracy were 0.1-0.9% RSD (n=10) and 97-106% recovery, respectively. Limits of detections of analytes were ranged from 0.2 to 1.2ngmL(-1). The current sweeping-MEKC achieved sensitivity enhancement factor (SEF) up to 183-fold of analytes concentrations compared to other hitherto published CE reports that is suitable to find out the trace amounts of catechins in plasma.

  6. The effects of corrugation and wing planform on the aerodynamic force production of sweeping model insect wings

    Institute of Scientific and Technical Information of China (English)

    Guoyu Luo; Mao Sun

    2005-01-01

    The effects of corrugation and wing planform (shape and aspect ratio) on the aerodynamic force production of model insect wings in sweeping (rotating after an initial start) motion at Reynolds number 200 and 3500 at angle of attack 40° are investigated, using the method of computational fluid dynamics. A representative wing corrugation is considered. Wing-shape and aspect ratio (AR) of ten representative insect wings are considered; they are the wings of fruit fly, cranefly, dronefly, hoverfly, ladybird, bumblebee, honeybee, lacewing (forewing), hawkmoth and dragonfly (forewing), respectively (AR of these wings varies greatly,from 2.84 to 5.45). The following facts are shown.(1) The corrugated and flat-plate wings produce approximately the same aerodynamic forces. This is because for a sweeping wing at large angle of attack, the length scale of the corrugation is much smaller than the size of the separated flow region or the size of the leading edge vortex (LEV). (2) The variation in wing shape can have considerable effects on the aerodynamic force; but it has only minor effects on the force coefficients when the velocity at r2 (the radius of the second moment of wing area) is used as the reference velocity; i.e.the force coefficients are almost unaffected by the variation in wing shape. (3) The effects of AR are remarkably small:when AR increases from 2.8 to 5.5, the force coefficients vary only slightly; flowfield results show that when AR is relatively large, the part of the LEV on the outer part of the wings sheds during the sweeping motion. As AR is increased, on one hand,the force coefficients will be increased due to the reduction of 3-dimensional flow effects; on the other hand, they will be decreased due to the shedding of pan of the LEV; these two effects approximately cancel each other, resulting in only minor change of the force coefficients.

  7. Method to synthesize polynomial current waveforms and intensity compensation functions for DFB lasers in digital sweep integration gas analyzers.

    Science.gov (United States)

    Kidd, Gary

    2002-09-01

    With analysis methods using digital sweep integration of the absorbance function, linear current ramps can produce non-linear laser intensity and wavenumber functions from distributed feedback lasers. These non-linear functions produce offset and gain errors in mole fraction estimates on tunable diode laser gas analyzers. A method is described to synthesize polynomial current waveforms and laser intensity compensation functions to give linear wavenumber functions and to minimize the offset error. Quantitative and qualitative results are presented to evaluate reduction in mole fraction errors.

  8. Generation of constant-amplitude radio-frequency sweeps at a tunnel junction for spin resonance STM

    Science.gov (United States)

    Paul, William; Baumann, Susanne; Lutz, Christopher P.; Heinrich, Andreas J.

    2016-07-01

    We describe the measurement and successful compensation of the radio-frequency transfer function of a scanning tunneling microscope over a wide frequency range (15.5-35.5 GHz) and with high dynamic range (>50 dB). The precise compensation of cabling resonances and attenuations is critical for the production of constant-voltage frequency sweeps for electric-field driven electron spin resonance (ESR) experiments. We also demonstrate that a well-calibrated tunnel junction voltage is necessary to avoid spurious ESR peaks that can arise due to a non-flat transfer function.

  9. Improved performance of linear coal cutting compared with rotary cutting. Report of investigations/1995

    Energy Technology Data Exchange (ETDEWEB)

    Roepke, W.W.; Hanson, B.D.; Olson, R.C.; Wingquist, C.F.; Myren, T.A.

    1995-07-01

    The linear cutting system, developed by the U.S. Bureau of Mines, uses geometric principles developed by Cardan to produce a nearly constant cut depth. The new system has been extensively tested in a synthetic material under laboratory conditions to verify mechanical capability and to identify operational characteristics. Comparisons between 15-rpm linear cutting and 50-rpm rotary cutting systems show significant improvement in respirable dust entrainment, product size distribution, and energy usage. Respirable dust is reduced by as much as 90 pct. Recovered product showed a 67-pct reduction in -0.32-cm (-1/8-in) material and a 200-pct increase in +5.08 cm (+2 in) material. Average power was reduced by 66 pct for the linear cutting. Because the bit cutting paths differ between linear and rotary cutting, it was necessary to compare the two at the same cut depths and bit types. These comparisons show that low revolution per minute rotary cutting entrains about the same amount of respirable dust as the linear cutting system, but the average shaft torque may be 55 to 130 pct greater for the rotary system.

  10. An FMS Dynamic Production Scheduling Algorithm Considering Cutting Tool Failure and Cutting Tool Life

    Science.gov (United States)

    Setiawan, A.; Wangsaputra, R.; Martawirya, Y. Y.; Halim, A. H.

    2016-02-01

    This paper deals with Flexible Manufacturing System (FMS) production rescheduling due to unavailability of cutting tools caused either of cutting tool failure or life time limit. The FMS consists of parallel identical machines integrated with an automatic material handling system and it runs fully automatically. Each machine has a same cutting tool configuration that consists of different geometrical cutting tool types on each tool magazine. The job usually takes two stages. Each stage has sequential operations allocated to machines considering the cutting tool life. In the real situation, the cutting tool can fail before the cutting tool life is reached. The objective in this paper is to develop a dynamic scheduling algorithm when a cutting tool is broken during unmanned and a rescheduling needed. The algorithm consists of four steps. The first step is generating initial schedule, the second step is determination the cutting tool failure time, the third step is determination of system status at cutting tool failure time and the fourth step is the rescheduling for unfinished jobs. The approaches to solve the problem are complete-reactive scheduling and robust-proactive scheduling. The new schedules result differences starting time and completion time of each operations from the initial schedule.

  11. Definition of fine cutting features for laser fusion cutting of stainless steel

    Science.gov (United States)

    Seebach, J.; Norman, S.; Harrison, P.

    2015-07-01

    Laser fusion cutting of stainless steel is often considered in a material range from 0,3mm up to 4mm and laser powers up to 2kW. For a given material thickness, different optimum beam and process parameters can be determined empirically, leading to a dross-free cut for high tool travel speeds. Realising sharp 90-degree corners, dross formation is observed and leads to a deteriorated cutting quality. With reorientation at small radii, the speed-dependent change in the cutting process is superimposed by the existing beam to nozzle misalignment and contributes to the stability of a cut. The feature radius R on the stability of the cutting process is being determined by reducing feature radius R. In this paper, cutting of different radii for different sized conventional nozzles is considered and analysed. Based on cutting quality evaluation, fine feature cutting is defined by discussing thickness-dependent finest cutting feature for a given gas dynamic input.

  12. Rational cutting height for large cutting height fully mechanized top-coal caving

    Institute of Scientific and Technical Information of China (English)

    Huang Bingxiang; Li Hongtao; Liu Changyou; Xing Shijun; Xue Weichao

    2011-01-01

    Large cutting height fully mechanized top-coal caving is a new mining method that improves recovery ratio and single-pass production.It also allows safe and efficient mining.A rational cutting height is one key parameter of this technique.Numerical simulation and a granular-media model experiment were used to analyze the effect of cutting height on the rock pressure of a fully mechanized top-coal caving work face.The recovery ratio was also studied.As the cutting height increases the top-coal thickness is reduced.Changing the ratio of cutting to drawing height intensifies the face pressure and the top-coal shattering.A maximum cutting height exists under a given set of conditions due to issues with surrounding rock-mass control.An increase in cutting height makes the top-coal cave better and the recovery ratio when drawing top-coal is then improved.A method of adjusting the face rock pressure is presented.Changing the cutting to drawing height ratio is the technique used to control face rock pressure.The recovery ratio when cutting coal exceeds that when caving top-coal so the face recovery ratio may be improved by over sizing the cutting height and increasing the top-coal drawing ratio.An optimum ratio of cutting to drawing height exists that maximizes the face recovery ratio.A rational cutting height is determined by comprehensively considering the surrounding rock-mass control and the recovery ratio.At the same time increasing the cutting height can improve single pass mining during fully mechanized top-coal caving.

  13. Laser Cutting of Leather: Tool for Industry or Designers?

    Science.gov (United States)

    Stepanov, Alexander; Manninen, Matti; Pärnänen, Inni; Hirvimäki, Marika; Salminen, Antti

    Currently technologies which are applied for leather cutting include slitting knifes, die press techniques and manual cutting. Use of laser technology has grown significantly during recent years due to number of advantages over conventional cutting methods; flexibility, high production speed, possibility to cut complex geometries, easier cutting of customized parts, and less leftovers of leather makes laser cutting more and more economically attractive to apply for leather cutting. Laser technology provides advantages in cutting complex geometries, stable cutting quality and possibility to utilize leather material in economically best way. Constant quality is important in industrial processes and laser technology fulfills this requirement: properly chosen laser cutting parameters provides identical cuts. Additionally, laser technology is very flexible in terms of geometries: complex geometries, individual designs, prototypes and small scale products can be manufactured by laser cutting. Variety of products, which needed to be cut in small volumes, is also the application where laser cutting can be more beneficial due to possibility to change production from one product to another only by changing geometry without a need to change cutting tool. Disadvantages of laser processing include high initial investment costs and some running costs due to maintenance and required gas supply for the laser. Higher level of operator's expertise is required due to more complicated machinery in case of laser cutting. This study investigates advantages and disadvantages of laser cutting in different areas of application and provides comparison between laser cutting and mechanical cutting of leather.

  14. Thermoelectrical numerical model of electrosurgical rf cutting

    Science.gov (United States)

    Protsenko, Dmitry E.; Pearce, John A.

    2001-06-01

    We developed a 3D thermo-electrical model of RF tissue cutting that takes into account variations in electrical and thermal properties with temperature and water content, dynamics of water evaporation and thermal and electrical processes at the tissue-scalpel interface. The model predicts measurable parameters of the electric circuit (tissue impedance, ESU output RMS voltage and current) and tissue cutting rate. Results of numerical simulations suggest that high circuit impedance during electrosurgical cutting can result not only from tissue dehydration but from the configuration of the electric field as well. It appears that the area of tissue-scalpel electric contact is significantly smaller than the area of the scalpel itself but is large enough to rule out electric sparks as a major mechanism of electrosurgical cutting.

  15. New opportunities for cutting with lasers.

    Science.gov (United States)

    Renner, Thomas; Mairhörmann, Dieter

    2004-01-01

    Laser microcutting is a leading technology for the manufacture of surgical instruments and medical implants. This article assesses its capabilities for stents and surgical-needle manufacture and for other tube-cutting applications that require microscaled designs.

  16. Cuts and coproducts of massive triangle diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Samuel [Higgs Centre for Theoretical Physics, School of Physics and Astronomy,The University of Edinburgh,Mayfield Road, Edinburgh EH9 3JZ, Scotland (United Kingdom); Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS,Orme des Merisiers, F-91191 Gif-sur-Yvette (France); Britto, Ruth [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS,Orme des Merisiers, F-91191 Gif-sur-Yvette (France); School of Mathematics, Trinity College,College Green, Dublin 2 (Ireland); Hamilton Mathematical Institute, Trinity College,College Green, Dublin 2 (Ireland); Grönqvist, Hanna [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS,Orme des Merisiers, F-91191 Gif-sur-Yvette (France)

    2015-07-21

    Relations between multiple unitarity cuts and coproducts of Feynman integrals are extended to allow for internal masses. These masses introduce new branch cuts, whose discontinuities can be derived by placing single propagators on shell and identified as particular entries of the coproduct. First entries of the coproduct are then seen to include mass invariants alone, as well as threshold corrections for external momentum channels. As in the massless case, the original integral can possibly be recovered from its cuts by starting with the known part of the coproduct and imposing integrability contraints. We formulate precise rules for cuts of diagrams, and we gather evidence for the relations to coproducts through a detailed study of one-loop triangle integrals with various combinations of external and internal masses.

  17. Oil Refining Giants to Cut Output

    Institute of Scientific and Technical Information of China (English)

    Zhang Dingmin

    2002-01-01

    @@ China's refined oil product output rose slightly in the first five months of this year on strong demand,but the two biggest domestic producers plan to cut production rates in an attempt to bolster the sluggish price.

  18. On Triple-Cut of Scattering Amplitudes

    CERN Document Server

    Mastrolia, Pierpaolo

    2007-01-01

    It is analysed the triple-cut of one-loop amplitudes in dimensional regularisation within spinor-helicity representation. The triple-cut is defined as a difference of two double-cuts with the same particle content, and a same propagator carrying, respectively, causal and anti-causal prescription in each of the two cuts. That turns out into an effective tool for extracting the coefficients of the three-point functions (and higher-point ones) from one-loop-amplitudes. The phase-space integration is oversimplified by using residues theorem to perform the integration over the spinor variables, via the holomorphic anomaly, and a trivial integration on the Feynman parameter. The results are valid for arbitrary values of dimensions.

  19. Correlation of cutting fluid performance in different machining operations

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Belluco, Walter

    2001-01-01

    An analysis of cutting fluid performance in different metal cutting operations is presented, based on experimental investigations in which type of operation, performance criteria, work material, and fluid type are considered. Cutting fluid performance was evaluated in turning, drilling, reaming...

  20. Frequency sweep jitter and wander of a Vernier-Tuned Distributed Bragg Reflector (VT-DBR) laser at 1550 nm in OCT applications

    Science.gov (United States)

    Martens Biersach, R. C.; Derickson, Dennis; Ensher, Jason

    2015-07-01

    The short-term jitter and longer-term wander of the frequency sweep profile of a Vernier-Tuned Distributed Bragg Reflector (VT-DBR) laser at 1550 nm used in OCT applications is characterized in this work. The VT-DBR has demonstrated success in source-swept OCT (SSOCT), performing both intensity [1] and phase-sensitive [2] OCT. The purpose of this paper is to investigate one of the unique aspects of the VT-DBR laser that makes it successful in OCT: the stability of the linear optical frequency sweep of the source. Jitter measurements of the optical frequency sweep are recorded using a 3-cavity 100 GHz free spectral range (FSR) solid etalon. A gas absorption reference cell is used for wander characterization. We report that the VT-DBR jitters by no more than 82 MHz RMS in optical frequency while sweeping at an 8 kHz repetition rate. Longer-term wander provides insight into the accuracy of the VT-DBR selfcalibration routine which produces an intrinsically linear optical frequency sweep. Over an 8-hour data collection period, the system maintains a linear sweep with an optical frequency step of 105 MHz per 2.5 ns with +/- 3 kHz per 2.5 ns (+/- 0.03%) peak-to-peak deviation. We find that the absolute frequency drifts by 325 MHz (2.6pm) over the same 8- hour period with ambient temperature fluctuations of no more than 5 °C. Results show that using calibration with a gas reference cell, picometer absolute wavelength accuracy of the laser can be achieved at any time for a single sweep. Stability and accuracy limits are thought to be due to electronic drive circuitry in the current design.

  1. Link between chips and cutting moments evolution

    CERN Document Server

    Cahuc, Olivier; Gérard, Alain; 10.4028/WWW.scientific.net/AMR.423.89

    2012-01-01

    The better understanding of the material cutting process has been shown with the benefit of the forces and moments measurement since some years ago. In paper, simultaneous six mechanical components and chip orientation measurements were realized during turning tests. During these tests, the influence of the depth of cut or feed rate has been observed and a link between the chip orientation and the moment vector orientation or the central axis characteristics has been shown.

  2. From Dimensional to Cut-Off Regularization

    CERN Document Server

    Dillig, M

    2006-01-01

    We extent the standard approach of dimensional regularization of Feynman diagrams: we replace the transition to lower dimensions by a 'natural' cut-off regulator. Introducing an external regulator of mass Lambda^(2e), we regain in the limit e -> 0 and e > 0 the results of dimensional and cut-off regularization, respectively. We demonstrate the versatility and adequacy of the different regularization schemes for practical examples (such as non covariant regularization, the axial anomaly or regularization in effective field theories).

  3. Rooting of carnation cuttings: The auxin signal

    OpenAIRE

    Acosta, Manuel; Oliveros-Valenzuela, M Rocío; Nicolás, Carlos; Sánchez-Bravo, José

    2009-01-01

    The rooting of stem cuttings is a common vegetative propagation practice in many ornamental species. Among other signals, auxin polarly transported through the stem plays a key role in the formation and growth of adventitious roots. Unlike in other plant species, auxin from mature leaves plays a decisive role in the rooting of carnation (Dianthus caryophyllus. L) cuttings. The gene DcAUX1, which codifies an auxin influx carrier involved in polar auxin transport, has now been cloned and charac...

  4. Cut Size Statistics of Graph Bisection Heuristics

    OpenAIRE

    Schreiber, G. R.; Martin, O. C.

    1998-01-01

    We investigate the statistical properties of cut sizes generated by heuristic algorithms which solve approximately the graph bisection problem. On an ensemble of sparse random graphs, we find empirically that the distribution of the cut sizes found by ``local'' algorithms becomes peaked as the number of vertices in the graphs becomes large. Evidence is given that this distribution tends towards a Gaussian whose mean and variance scales linearly with the number of vertices of the graphs. Given...

  5. Geometric Modelling by Recursively Cutting Vertices

    Institute of Scientific and Technical Information of China (English)

    吕伟; 梁友栋; 等

    1989-01-01

    In this paper,a new method for curve and surface modelling is introduced which generates curves and surfaces by recursively cutting and grinding polygons and polyhedra.It is a generalization of the existing corner-cutting methods.A lot of properties,such as geometric continuity,representation,shape-preserving,and the algorithm are studied which show that such curves and surfaces are suitable for geometric designs in CAD,computer graphics and their application fields.

  6. Cutting Symmetrical Recesses In Soft Ceramic Tiles

    Science.gov (United States)

    Nesotas, Tony C.; Tyler, Brent

    1989-01-01

    Simple tool cuts hemispherical recesses in soft ceramic tiles. Designed to expose wires of thermocouples embedded in tiles without damaging leads. Creates neat, precise holes around wires. End mill includes axial hole to accommodate thermocouple wires embedded in material to be cut. Wires pass into hole without being bent or broken. Dimensions in inches. Used in place of such tools as dental picks, tweezers, spatulas, and putty knives.

  7. Alternative Metal Hot Cutting Operations for Opacity

    Science.gov (United States)

    2014-11-01

    testing was conducted on 9/32” ordinary strength steel bulkhead section from the ex-CGN-9 and, if possible, 2” high yield strength steel ( HY80 ...recorded for both the alternative fuel and propane. Test cuts were on 9/32” steel surface ship sections with additional demonstration cuts performed on...thicker surface ship sections and 2” high yield strength steel submarine pressure hull as the pieces became available. The results from the

  8. LASER CUTTING MACHINES FOR 3-D THIN SHEET PARTS

    Directory of Open Access Journals (Sweden)

    Miroslav RADOVANOVIC

    2012-11-01

    Full Text Available Laser cutting machines are used for precise contour cutting thin sheet. In industrial application nowadays various types and construction of laser cutting machines can be met. For contour cutting 3-D thin sheet parts laser cutting machines with rotation movements and laser robots are used. Laser generates the light beam, that presents a tool in working process. Application of laser cutting machines made possible good quality of products, flexibility of production and enlargement of economy

  9. New law to cut 1986 budgets

    Science.gov (United States)

    Katzoff, Judith A.

    The National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), the National Science Foundation (NSF), and the U.S. Geological Survey (USGS) are among the agencies whose budgets are likely to be cut 4.3% on March 1, 1986, when the Balanced Budget and Emergency Deficit Control Act of 1985 makes its first impact.Under the law, the cuts will be implemented across the board by an order from the president. Unless Congress passes legislation to make its own cuts sometime between now and March 1, these cuts will automatically take an equal percentage from every nondefense program, project, and activity not protected from “sequestration” of funds and will automatically take a slightly higher percentage from the unprotected portions of the defense budget. Individual agencies could circumvent the across-the-board cuts by formulating their own plans to distribute their share of the reductions; however, these plans would need congressional approval. These cuts will affect budgets for the federal government in fiscal year (FY) 1986, which began on October 1, 1985. Unless revenues increase substantially, additional and mone severe belt-tightening is in store for FY 1987 and beyond.

  10. Demonstrating diamond wire cutting of the TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Rule, K.; Perry, E.; Larson, S.; Viola, M. [and others

    2000-02-24

    The Tokamak Fusion Test Reactor (TFTR) ceased operation in April 1997 and decommissioning commenced in October 1999. The deuterium-tritium fusion experiments resulted in contaminating the vacuum vessel with tritium and activating the materials with 14 Mev neutrons. The total tritium content within the vessel is in excess of 7,000 Curies while dose rates approach 50 mRem/hr. These radiological hazards along with the size of the Tokamak (100 cubic meters) present a unique and challenging task for dismantling. Plasma arc cutting is the current baseline technology for the dismantlement of fission reactors. This technology is typically used because of its faster cutting times. Alternatively, an innovative approach for dismantlement of the TFTR is the use of diamond wire cutting technology. Recent improvements in diamond wire technology have allowed the cutting of carbon steel components such as pipe, plate, and tube bundles in heat exchangers. Some expected benefits of this technology include: significantly reduction in airborne contaminates, reduced personnel exposure, a reduced risk of spread of tritium contamination, and reduced overall costs as compared to using plasma arc cutting. This paper will provide detailed results of the diamond wire cutting demonstration that was completed in September of 1999, on a mock-up of this complex reactor. The results will identify cost, safety, industrial and engineering parameters, and the related performance of each situation.

  11. Plasma arc cutting technology: simulation and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Cantoro, G; Colombo, V; Concetti, A; Ghedini, E; Sanibondi, P; Zinzani, F; Rotundo, F [Department of Mechanical Engineering (D.I.E.M.) and Research Center for Applied Mathematics (C.I.R.A.M.), Alma Mater Studiorum-Universita di Bologna, Via Saragozza 8, 40123 Bologna (Italy); Dallavalle, S; Vancini, M, E-mail: emanuele.ghedini@unibo.it [Cebora S.p.A., Via Andrea Costa 24, 40057 Cadriano di Granarolo (Italy)

    2011-01-01

    Transferred arc plasma torches are widely used in industrial processes for cutting of metallic materials because of their ability to cut a wide range of metals with very high productivity. The process is characterized by a transferred electric arc established between an electrode inside the torch (the cathode) and another electrode, the metallic workpiece to be cut (the anode). In order to obtain a high quality cut and a high productivity, the plasma jet must be as collimated as possible and must have the higher achievable power density. Plasma modelling and numerical simulation can be very useful tools for the designing and optimizing these devices, but research is still in the making for finding a link between simulation of the plasma arc and a consistent prevision of cut quality. Numerical modelling of the behaviour of different types of transferred arc dual gas plasma torches can give an insight on the physical reasons for the industrial success of various design and process solutions that have appeared over the last years. Diagnostics based on high speed imaging and Schlieren photography can play an important role for investigating piercing, dross generation, pilot arcing and anode attachment location. Also, the behaviour of hafnium cathodes at high current levels at the beginning of their service life can been experimentally investigated, with the final aim of understanding the phenomena that take place during those initial piercing and cutting phases and optimizing the initial shape of the surface of the emissive insert exposed to plasma atmosphere.

  12. Ion implantation of superhard ceramic cutting tools

    Science.gov (United States)

    Chou, Y. Kevin; Liu, Jie

    2004-08-01

    Despite numerous reports of tool life increase by ion implantation in machining operations, ion implantation applications of cutting tools remain limited, especially for ceramic tools. Mechanisms of tool-life improvement by implantation are not clearly established due to complexity of both implantation and tool-wear processes. In an attempt to improve performance of cubic boron nitride (CBN) tools for hard machining by ion implantation, a literature survey of ion-implanted cutting tools was carried out with a focus on mechanisms of tool-wear reduction by ion implantation. Implantation and machining experiments were then conducted to investigate implantation effects on CBN tools in hard machining. A batch of CBN tools was implanted with nitrogen ions at 150 keV and 2.5×1017 ions/cm2 and further used to cut 61 HRc AISI 52100 steel at different conditions. Results show that ion implantation has strong effects on partsurface finish, moderate effect on cutting forces, but an insignificant impact on tool wear. Friction coefficients, estimated from measured cutting forces, are possibly reduced by ion implantation, which may improve surface finish. However, surprisingly, 2-D orthogonal cutting to evaluate tribological loading in hard machining showed no difference on contact stresses and friction coefficients between implanted and nonimplanted CBN tools.

  13. Quantum Max-flow/Min-cut

    Science.gov (United States)

    Cui, Shawn X.; Freedman, Michael H.; Sattath, Or; Stong, Richard; Minton, Greg

    2016-06-01

    The classical max-flow min-cut theorem describes transport through certain idealized classical networks. We consider the quantum analog for tensor networks. By associating an integral capacity to each edge and a tensor to each vertex in a flow network, we can also interpret it as a tensor network and, more specifically, as a linear map from the input space to the output space. The quantum max-flow is defined to be the maximal rank of this linear map over all choices of tensors. The quantum min-cut is defined to be the minimum product of the capacities of edges over all cuts of the tensor network. We show that unlike the classical case, the quantum max-flow=min-cut conjecture is not true in general. Under certain conditions, e.g., when the capacity on each edge is some power of a fixed integer, the quantum max-flow is proved to equal the quantum min-cut. However, concrete examples are also provided where the equality does not hold. We also found connections of quantum max-flow/min-cut with entropy of entanglement and the quantum satisfiability problem. We speculate that the phenomena revealed may be of interest both in spin systems in condensed matter and in quantum gravity.

  14. EXPERIMENTAL ESTIMATION OF TOOL WEAR AND CUTTING TEMPERATURES IN MQL USING CUTTING FLUIDS WITH CNT INCLUSION

    Directory of Open Access Journals (Sweden)

    S.NARAYANA RAO,

    2011-04-01

    Full Text Available Machining often witnesses frequent interruption caused by friction and heat. Cutting fluids are being used in machining for centuries to counter the effects of friction and temperatures. However, because of many disadvantages, MQL has emerged. MQL demands fluids with high performance. This work tries to estimate tool wear and cutting temperatures while using cutting fluids, prepared with carbon nano tube (CNT inclusion.

  15. Generalized logarithmic scaling for high-order moments of the longitudinal velocity component explained by the random sweeping decorrelation hypothesis

    Science.gov (United States)

    Katul, Gabriel G.; Banerjee, Tirtha; Cava, Daniela; Germano, Massimo; Porporato, Amilcare

    2016-09-01

    Expressions for the logarithmic variations of the normalized turbulent longitudinal velocity (u2p ¯ +) 1 /p with normalized distance z/δ from a boundary for high-order (p) moments in the intermediate region of wall bounded flows characterized by thickness δ are derived. The ansatz that ( u2p¯ +) 1 /pvariationin ln(z/δ) originates from a compound effect of random sweeping and -1 power-law scaling in the longitudinal velocity spectrum Eu(k) is discussed, where k is the wavenumber. Using velocity time series sampled above a uniform ice sheet, an Eu(k) ˜ k-1 scaling is confirmed for kz 1. The data were then used to analyze assumptions required for the utility of the random sweeping decorrelation (RSD) hypothesis connecting the k-1 power-law with log-scaling in (u2p ¯ +) 1 /p. It has been found out that while the RSD hypothesis is operationally applicable to scales associated with attached eddies bounded by kz 1, significant interactions among high-order turbulent velocity and velocity increments lead to the conclusion that the RSD hypothesis cannot be exactly valid. Its operational utility stems from the observations that some of the interaction terms among the high-order velocity and velocity increments act in opposite directions thereby canceling their additive effects in RSD.

  16. Acoustic guided waves in cylindrical solid-fluid structures: Modeling with a sweeping frequency finite element method and experimental validation

    Science.gov (United States)

    Liu, Yang; D'Angelo, Ralph M.; Sinha, Bikash K.; Zeroug, Smaine

    2017-02-01

    Modeling and understanding the complex elastic-wave physics prevalent in solid-fluid cylindrically-layered structures is of importance in many NDE fields, and most pertinently in the domain of well integrity evaluation of cased holes in the oil and gas industry. Current sonic measurements provide viable techniques for well integrity evaluation yet their practical effectiveness is hampered by the current lack of knowledge of acoustic wave fields particularly in complicated cased-hole geometry where for instance two or more nested steel strings are present in the borehole. In this article, we propose and implement a Sweeping Frequency Finite Element Method (SFFEM) for acoustic guided waves simulation in complex geometries that include double steel strings cemented to each other and to the formation and where the strings may be non-concentric. Transient dynamic finite element models are constructed with sweeping frequency signals being applied as the excitation sources. The sources and receivers disposition simulate current sonic measurement tools deployed in the oilfield. Synthetic wavetrains are recorded and processed with modified matrix pencil method to isolate both the dispersive and non-dispersive propagating guided wave modes. Scaled experiments of fluid-filled double strings with dimensions mimicking the real ones encountered in the field have also been carried out to generate reference data. A comparison of the experimental and numerical results indicates that the SFFEM is capable of accurately reproducing the rich and intricate higher-order multiple wave fields observed experimentally in the fluid-filled double string geometries.

  17. Laser cutting of various materials: Kerf width size analysis and life cycle assessment of cutting process

    Science.gov (United States)

    Yilbas, Bekir Sami; Shaukat, Mian Mobeen; Ashraf, Farhan

    2017-08-01

    Laser cutting of various materials including Ti-6Al-4V alloy, steel 304, Inconel 625, and alumina is carried out to assess the kerf width size variation along the cut section. The life cycle assessment is carried out to determine the environmental impact of the laser cutting in terms of the material waste during the cutting process. The kerf width size is formulated and predicted using the lump parameter analysis and it is measured from the experiments. The influence of laser output power and laser cutting speed on the kerf width size variation is analyzed using the analytical tools including scanning electron and optical microscopes. In the experiments, high pressure nitrogen assisting gas is used to prevent oxidation reactions in the cutting section. It is found that the kerf width size predicted from the lump parameter analysis agrees well with the experimental data. The kerf width size variation increases with increasing laser output power. However, this behavior reverses with increasing laser cutting speed. The life cycle assessment reveals that material selection for laser cutting is critical for the environmental protection point of view. Inconel 625 contributes the most to the environmental damages; however, recycling of the waste of the laser cutting reduces this contribution.

  18. Approaching over 10 000-fold sensitivity increase in chiral capillary electrophoresis: Cation-selective exhaustive injection and sweeping cyclodextrin-modified micellar electrokinetic chromatography.

    Science.gov (United States)

    Mikuma, Toshiyasu; Iwata, Yuko T; Miyaguchi, Hajime; Kuwayama, Kenji; Tsujikawa, Kenji; Kanamori, Tatsuyuki; Kanazawa, Hideko; Inoue, Hiroyuki

    2016-11-01

    A novel and simple method that combines an online concentration technique with an enantioseparation technique for capillary electrophoresis-namely, cation-selective exhaustive injection and sweeping cyclodextrin-modified micellar electrokinetic chromatography (CSEI-sweeping CD-modified MEKC)-realizes the effective enantioseparation of cationic analytes while keeping a significant increase of detection sensitivity. This technique consists of a slight modification of the basic CSEI-sweeping MEKC. The main idea is to simply add an anionic CD as a chiral selector into the micellar buffer including sodium dodecyl sulfate, but not to change any other buffers in order to preserve the online concentration mechanism. When applied to analysis of the street drug, methamphetamine, the method achieved not only a baseline enantioseparation but also limits of detection (LODs; S/N = 3) of 70-90 pg/mL (ppt) for each isomer. This translates to a more than 10 000-fold improvement compared to the LODs by the usual injection method. The present technique, which was made from a slight modification of CSEI-sweeping MEKC, would give an attractive approach that is applicable to almost any analytes for which CSEI-sweeping MEKC is applicable; all that is required is the selection of an appropriate anionic CD to be added to the micellar buffer.

  19. Effects of leading edge sweep angle and design lift coefficient on performance of a modified arrow wing at a design Mach number of 2.6

    Science.gov (United States)

    Mack, R. J.

    1974-01-01

    Wing models were tested in the high-speed section of the Langley Unitary Plan wind tunnel to study the effects of the leading-edge sweep angle and the design lift coefficient on aerodynamic performance and efficiency. The models had leading-edge sweep angles of 69.44 deg, 72.65 deg, and 75.96 deg which correspond to values of the design Mach-number-sweep-angle parameter (beta cotangent A) sub DES of 0.6, 0.75, and 0.9, respectively. For each sweep angle, camber surfaces having design lift coefficients of 0,0.08, and 0.12 at a design Mach number of 2.6 were generated. The wind-tunnel tests were conducted at Mach numbers of 2.3, 2.6, and 2.96 with a stagnation temperature of 338.7 K (150 F) and a Reynolds number per meter of 9.843 times 10 to the 6th power. The results of the tests showed that only a moderate sweeping of the wing leading edge aft of the Mach line along with a small-to-moderate amount of camber and twist was needed to significantly improve the zero-lift (flat camber surface) wing performance and efficiency.

  20. The size effect in metal cutting

    Indian Academy of Sciences (India)

    Milton C Shaw

    2003-10-01

    When metal is removed by machining there is substantial increase in the specific energy required with decrease in chip size. It is generally believed this is due to the fact that all metals contain defects (grain boundaries, missing and impurity atoms, etc.), and when the size of the material removed decreases, the probability of encountering a stress-reducing defect decreases. Since the shear stress and strain in metal cutting is unusually high, discontinuous microcracks usually form on the metal-cutting shear plane. If the material being cut is very brittle, or the compressive stress on the shear plane is relatively low, microcracks grow into gross cracks giving rise to discontinuous chip formation. When discontinuous microcracks form on the shear plane they weld and reform as strain proceeds, thus joining the transport of dislocations in accounting for the total slip of the shear plane. In the presence of a contaminant, such as CCl4 vapour at a low cutting speed, the rewelding of microcracks decreases, resulting in decrease in the cutting force required for chip formation. A number of special experiments are described in the paper that support the transport of microcracks across the shear plane, and the important role compressive stress plays on the shear plane. Relatively recently, an alternative explanation for the size effect in cutting was provided based on the premise that shear stress increases with increase in strain rate. When an attempt is made to apply this to metal cutting by Dinesh et al (2001) it is assumed in the analysis that the von Mises criterion pertains to the shear plane. This is inconsistent with the experimental findings of Merchant. Until this difficulty is taken care of, together with the promised experimental verification of the strain rate approach, it should be assumed that the strain rate effect may be responsible for some notion of the size effect in metal cutting. However, based on the many experiments discussed here, it is

  1. Comparing efficacy of a sweep net and a dip method for collection of mosquito larvae in large bodies of water in South Africa [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Katherine K. Brisco

    2016-04-01

    Full Text Available In this study we tested an alternative method for collecting mosquito larvae called the sweep net catch method and compared its efficiency to that of the traditional dip method. The two methods were compared in various water bodies within Kruger National Park and Lapalala Wilderness area, South Africa. The sweep net catch method performed 5 times better in the collection of Anopheles larvae and equally as well as the dip method in the collection of Culex larvae (p =8.58 x 10-5. Based on 15 replicates the collector’s experience level did not play a significant role in the relative numbers of larvae collected using either method. This simple and effective sweep net catch method will greatly improve the mosquito larval sampling capacity in the field setting.

  2. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.; Kooten, van O.

    2005-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5°C. Intact (control) fruits were stored in the same conditions. The antioxidant activity was evalu

  3. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.

    2006-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5 °C. Intact fruits were stored in the same conditions as a control. The antioxidant activity was e

  4. Effects of cutting and maturity on antioxidant activity of fresh-cut tomatoes

    NARCIS (Netherlands)

    Moreira Lana, M.; Tijskens, L.M.M.

    2006-01-01

    To investigate the changes in total antioxidant activity of fresh-cut tomato during storage, tomato fruits harvested at three different stages of maturity were cut into 7-mm thick slices and stored at 5 °C. Intact fruits were stored in the same conditions as a control. The antioxidant activity was e

  5. Laser cutting of rectangular geometry into aluminum alloy: Effect of cut sizes on thermal stress field

    Science.gov (United States)

    Akhtar, Sohail; Kardas, Omer Ozgur; Keles, Omer; Yilbas, Bekir Sami

    2014-10-01

    Laser cutting of a rectangular geometry into aluminum alloy 2024 is carried out. Temperature and stress fields are predicted in the cutting section using the ABAQUS finite element code in line with the experimental conditions. Effect of the size of the rectangular geometry on the thermal stress fields is examined in the cutting section. Temperature predictions are validated through the thermocouple data. To identify the morphological changes in the cutting section, an experiment is carried out and the resulting cutting sections are examined under optical and scanning electron microscopes. It is found that temperature and stress fields are affected by the size of the rectangular cut geometry. Temperature and von Mises stress attains higher values for small size rectangular geometry as compared to its counterpart corresponding to the large size geometry. Laser cut sections are free from large size asperities including sideways burning and out-off flatness at the cut edges. Locally scattered some small dross attachments are observed at the kerf exit.

  6. Influence of cutting conditions on chip side curl

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    2004-01-01

    The paper describes the influence of local variations of contact length, cutting speed and material constraint, showing the effect of lubrication, on the side curl of the chip. The following examples are illustrated by experiments: cutting of a tube vs. cutting of a bar; cutting using a tool...

  7. Influence of cutting conditions on chip side curl

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    2004-01-01

    The paper describes the influence of local variations of contact length, cutting speed and material constraint, showing the effect of lubrication, on the side curl of the chip. The following examples are illustrated by experiments: cutting of a tube vs. cutting of a bar; cutting using a tool with...

  8. Investigations of Cutting Fluid Performance Using Different Machining Operations

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Belluco, Walter

    2002-01-01

    An analysis of cutting fluid performance in dif-ferent metal cutting operations is presented based on performance criteria, work material and fluid type. Cutting fluid performance was evaluated in turning, drilling, reaming and tapping operations, with respect to tool life, cutting forces and prod...

  9. Evaluation of Cutting Fluids in Multiple Reaming of Stainless Steel

    DEFF Research Database (Denmark)

    Belluco, Walter; Zeng, Z.; De Chiffre, Leonardo

    2001-01-01

    An investigation on the effect of different cutting fluids in reaming is presented. The performance of three water based cutting fluids and one cutting oil was compared to that of a reference water based commercial product by measurement of cutting forces, surface roughness and part accuracy. Three...

  10. 7 CFR 58.413 - Cutting and packaging rooms.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cutting and packaging rooms. 58.413 Section 58.413....413 Cutting and packaging rooms. When small packages of cheese are cut and wrapped, separate rooms shall be provided for the cleaning and preparation of the bulk cheese and for the cutting and...

  11. 21 CFR 882.4275 - Dowel cutting instrument.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dowel cutting instrument. 882.4275 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4275 Dowel cutting instrument. (a) Identification. A dowel cutting instrument is a device used to cut dowels of bone for bone grafting....

  12. STUDY ON SUB-DRY CUTTING GCr12

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Through the comparison study on cutting force, cutting temperature and machined surface quality with the sub-dry cutting traditional cooling method, it is shown that sub-dry cutting can retard the wear of the tooled parts. It is beneficial to realize the production without pollution and meet the demand of clean environment.

  13. Material testing of copper by extrusion-cutting

    DEFF Research Database (Denmark)

    Segalina, F.; De Chiffre, Leonardo

    2017-01-01

    was developed and implemented on a CNC lathe. An investigation was carried out extrusion-cutting copper discs using high-speed-steel cutting tools at 100 m/min cutting speed. Flow stress values for copper under machining-relevant conditions were obtained from measurement of the extrusion-cutting force...

  14. 49 CFR 236.52 - Relayed cut-section.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Relayed cut-section. 236.52 Section 236.52...: All Systems Track Circuits § 236.52 Relayed cut-section. Where relayed cut-section is used in... shall be open and the track circuit shunted when the track relay at such cut-section is in deenergized...

  15. Recent results in mirror based high power laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Nielsen, Jakob Skov; Elvang, Mads

    2004-01-01

    In this paper, recent results in high power laser cutting, obtained in reseach and development projects are presented. Two types of mirror based focussing systems for laser cutting have been developed and applied in laser cutting studies on CO2-lasers up to 12 kW. In shipyard environment cutting...

  16. Trim cut machining and surface integrity analysis of Nimonic 80A alloy using wire cut EDM

    Directory of Open Access Journals (Sweden)

    Amitesh Goswami

    2017-02-01

    Full Text Available This present work deals with the features of trim cut wire EDM machining of Nimonic 80A in terms of machining parameters, to predict material removal rate (MRR, surface roughness (Ra, wire wear ratio (WWR and microstructure analysis. Trim cut is performed after rough cut to remove the rough layer deposited after machining due to melting and re-solidification of the eroded metal from workpiece as well as from wire electrode. Taguchi’s design of experiments methodology has been used for planning and designing the experiments. The relative significance of various factors has also been evaluated and analyzed using ANOVA. The results clearly indicate trim cut potential for high surface finish compared to rough cut machining.

  17. The $\\mathcal{Q}$-cut Representation of One-loop Integrands and Unitarity Cut Method

    CERN Document Server

    Huang, Rijun; Rao, Junjie; Zhou, Kang; Feng, Bo

    2015-01-01

    Recently, a new construction for complete loop integrands of massless field theories has been proposed, with on-shell tree-level amplitudes delicately incorporated into its algorithm. This new approach reinterprets integrands in a novel form, namely the $\\mathcal{Q}$-cut representation. In this paper, by deriving one-loop integrands as examples, we elaborate in details the technique of this new representation, e.g., the summation over all possible $\\mathcal{Q}$-cuts as well as helicity states for the non-scalar internal particle in the loop. Moreover, we show that the integrand in the $\\mathcal{Q}$-cut representation naturally reduces to the integrand in the traditional unitarity cut method for each given cut channel, providing a cross-check for the new approach.

  18. Photonic mesophases from cut rod rotators

    Energy Technology Data Exchange (ETDEWEB)

    Stelson, Angela C.; Liddell Watson, Chekesha M., E-mail: cml66@cornell.edu [Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Avendano, Carlos [Chemical Engineering and Analytical Science, The University of Manchester, Manchester M13 9PL (United Kingdom)

    2016-01-14

    The photonic band properties of random rotator mesophases are calculated using supercell methods applied to cut rods on a hexagonal lattice. Inspired by the thermodynamic mesophase for anisotropic building blocks, we vary the shape factor of cut fraction for the randomly oriented basis. We find large, stable bandgaps with high gap isotropy in the inverted and direct structures as a function of cut fraction, dielectric contrast, and filling fraction. Bandgap sizes up to 34.5% are maximized at high dielectric contrast for rods separated in a matrix. The bandgaps open at dielectric contrasts as low as 2.0 for the transverse magnetic polarization and 2.25 for the transverse electric polarization. Additionally, the type of scattering that promotes the bandgap is correlated with the effect of disorder on bandgap size. Slow light properties are investigated in waveguide geometry and slowdown factors up to 5 × 10{sup 4} are found.

  19. Manipulation and cutting of carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nanomanipulation plays an important role in nanofabrication, it is also a technology necessary in exploring the secrets of nanoworld, and it thus beco mesa start point to research future nanomachine. In this study, manipulation and cutting of carbon nanotubes have been conducted in order to examine whether we can move a nanocomponent from one site to another by using the tip of atomic fo rce microscope (AFM). The technique may also be valuable for providing the const ructive materials of nanofabrication. While exploring the method for manipulatin g and cutting of nanotubes, some new phenomena have been observed during the process. Results show that carbon nanotubes present a feature of deformation combin ing bending and distortion when subjected to large mechanical forces exerted by the tip of AFM. In special cases, long carbon nanotubes can be cut into two part s, by which we can remove the part where crystal lattice is flawed, and therefor e a perfect nanocomponent can be obtained.

  20. ENVIRONMENTALLY REDUCING OF COOLANTS IN METAL CUTTING

    Directory of Open Access Journals (Sweden)

    Veijo KAUPPINEN

    2012-11-01

    Full Text Available Strained environment is a global problem. In metal industries the use of coolant has become more problematic in terms of both employee health and environmental pollution. It is said that the use of coolant forms approximately 8 - 16 % of the total production costs.The traditional methods that use coolants are now obviously becoming obsolete. Hence, it is clear that using a dry cutting system has great implications for resource preservation and waste reduction. For this purpose, a new cooling system is designed for dry cutting. This paper presents the new eco-friendly cooling innovation and the benefits gained by using this method. The new cooling system relies on a unit for ionising ejected air. In order to compare the performance of using this system, cutting experiments were carried out. A series of tests were performed on a horizontal turning machine and on a horizontal machining centre.

  1. COMPUTER AIDED DESIGN OF CUTTING TOOLS

    Directory of Open Access Journals (Sweden)

    Jakub Matuszak

    2015-11-01

    Full Text Available Correct and stable machining process requires an appropriate cutting tool. In most cases the tool can be selected by using special tool catalogs often available in online version. But in some cases there is a need to design unusual tools, for special treatment, which are not available in tool manufacturers’ catalogs. Proper tool design requires strength and geometric calculations. Moreover, in many cases specific technical documentation is required. By using Computer Aided Design of cutting tools this task can be carried out quickly and with high accuracy. Cutting tool visualization in CAD programs gives a clear overview of the design process. Besides, these programs provide the ability to simulate real machining process. Nowadays, 3D modeling in CAD programs is a fundamental tool for engineers. Therefore, it is important to use them in the education process.

  2. Basics of cutting and abrasive processes

    CERN Document Server

    Toenshoff, Hans Kurt

    2013-01-01

    Manufacturing is the basic industrial activity generating real value. Cutting and abrasive technologies are the backbone of precision production in machine, automotive and aircraft building as well as of production of consumer goods. We present the knowledge of modern manufacturing in these technologies on the basis of scientific research. The theory of cutting and abrasive processes and the knowledge about their application in industrial practice are a prerequisite for the studies of manufacturing science and an important part of the curriculum of the master study in German mechanical engineering. The basis of this book is our lecture “Basics of cutting and abrasive processes” (4 semester hours/3 credit hours) at the Leibniz University Hannover, which we offer to the diploma and master students specializing in manufacturing science.

  3. Laser Cutting of Materials of Various Thicknesses

    Directory of Open Access Journals (Sweden)

    Martin Grepl

    2012-01-01

    Full Text Available Thise paper deals with the application of laser technology and optimizing the parameters for cutting nickel alloy. The theoretical part of the paper describes various types of lasers, their principles and usage. The experimental part focuses on optimizing the section parameteres of Haynes 718 alloy using a CO2 gas laser. This alloy is employed in the production of components for the aircraft industry. The experiment was performed on the Wibro Delta laser system designed for sizable parts. The actual section is measured with respect to its quality and any accompanying side effects that occur during the process. In this case, laser output and cutting speed were the parameters with most influence on the final cut. The summary explains the results achieved in a metallographic laboratory.

  4. Cut Locus Construction using Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas; Anton, François;

    2011-01-01

    In this paper we present a method for appproximating cut loci for a given point p on Riemannian 2D manifolds, closely related to the notion of Voronoi diagrams. Our method finds the cut locus by advecting a front of points equally distant from p along the geodesics originating at p and finding...... the domain to have disk topology. We test our method for tori of revolution and compare our results to the benchmark ones from [2]. The method, however, is generic and can be easily adapted to construct cut loci for other manifolds of genera other than 1....... the lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  5. A framework for cut-over management

    Directory of Open Access Journals (Sweden)

    Guido Nageldinger

    2015-11-01

    Full Text Available The purpose of this paper is to provide a governance structure for IT-related projects in order to assure a safeguarded and timely transition to a productive environment. This transitioning, which rarely exceeds a weekend, is colloquially called ‘cut-over’, ‘rollout’ or ‘deployment’. The governance structure is defined in accordance with a set of project-specific deliverables for a cascade-type procedural project-management model, which is integrated within an Information Technology Infrastructure Library (ITIL-orientated service organization. This integration is illustrated by the use of a semi-agile release model. Due to the release model selected, which is particularly characterized by its bundling of projects for a release-specific rollout (as it is referred to in the project documentation, a new definition and interpretation of deployment from a generic ITIL perspective is required. The facilitated release model requires a distinction between a project-specific cut-over and a release-specific rollout. This separation gives rise to two types of go-live scenarios: one for each participating project and one for each release. Additionally, an interplay between cut-over planning for a project and rollout planning for a release becomes apparent. Projects should already incorporate cut-over related deliverables in the initial planning phase. Even though consulting methodologies such as ASAP (Accelerated SAP, recommend scattered, project-specific deliverables useful for cut-over planning, this publication offers an integrated approach on how to prepare systematically for a project-specific cut-over with all required deliverables. The framework provided maps out ITIL’s release and deployment process by means of IT projects; furthermore it allows IT projects to interface easily with the ITIL change-management process.

  6. ITER lip seal welding and cutting developments

    Energy Technology Data Exchange (ETDEWEB)

    Levesy, B.; Cordier, J.J.; Jokinen, T. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Kujanpää, V.; Karhu, M. [VTT Technical Research Centre of Finland (Finland); Le Barbier, R. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Määttä, T. [VTT Technical Research Centre of Finland (Finland); Martins, J.P.; Utin, Y. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

    2015-10-15

    Highlights: • Different TIG and Laser welding techniques are tested. • Twin spot laser welding techniques is the best. • Limited heat input gives a stable weld pool in all positions. • Penetrations is achieved. • Lip seal welding and cutting with a robotic arm is successfully performed on a representative mock-up. - Abstract: The welded lip seals form part of the torus primary vacuum boundary in between the port plugs and the vacuum vessel, and are classified as Protection Important Component. In order to refurbish the port plugs or the in-vessel components, port plugs have to be removed from the machine. The lip seal design must enable up to ten opening of the vacuum vessel during the life time operation of the ITER machine. Therefore proven, remote reliable cutting and re-welding are essential, as these operations need to be performed in the port cells in a nuclear environment, where human presence will be restricted. Moreover, the combination of size of the components to be welded (∼10 m long vacuum compatible thin welds) and the congested environment close to the core of the machine constraint the type and size of tools to be used. This paper describes the lip seal cutting and welding development programme performed at the VTT Technical Research Centre, Finland. Potential cutting and welding techniques are analyzed and compared. The development of the cutting, TIG and laser welding techniques on samples are presented. Effects of lip seal misalignments and optimization of the 2 welding processes are discussed. Finally, the manufacturing and test of the two 1.2 m × 1 m representative mock-ups are presented. The set-up and use of a robotic arm for the mock-up cutting and welding operations are also described.

  7. Combination of hollow fiber-based liquid-phase microextraction with sweeping techniques in micellar electrokinetic chromatography for the determination of Strychnos alkaloids in human urine

    Institute of Scientific and Technical Information of China (English)

    Xiao Huan Zang; Cai Rui Li; Qiu Hua Wu; Chun Wang; Dan Dan Han; Zhi Wang

    2007-01-01

    A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase rnicroextraction (LPME) based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electrokinetic chromatography was developed. The calibration curve was linear over the range of 20-200 ng mL-1 for both strychnine and brucine in human urine sample. The detection limits (S/N = 3:1) for strychnine and brucine were 1 ng mL-1 and 2 ng mL-1, respectively. The LPME-sweeping method has been successfully applied to the analysis of strychnine and brucine in real urine samples.

  8. Gate frequency sweep: An effective method to evaluate the dynamic performance of AlGaN/GaN power heterojunction field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Santi, C. de; Meneghini, M., E-mail: matteo.meneghini@dei.unipd.it; Meneghesso, G.; Zanoni, E. [Department of Information Engineering, University of Padua, via Gradenigo 6/B, Padova 35131 (Italy); Ishida, H.; Ueda, T. [Panasonic Corporation, Semiconductor Device Research Center, SDRC, 1 Kotari-yakemachi, Nagaokakyio City, Kyoto 317-8520 (Japan)

    2014-08-18

    With this paper we propose a test method for evaluating the dynamic performance of GaN-based transistors, namely, gate-frequency sweep measurements: the effectiveness of the method is verified by characterizing the dynamic performance of Gate Injection Transistors. We demonstrate that this method can provide an effective description of the impact of traps on the transient performance of Heterojunction Field Effect Transistors, and information on the properties (activation energy and cross section) of the related defects. Moreover, we discuss the relation between the results obtained by gate-frequency sweep measurements and those collected by conventional drain current transients and double pulse characterization.

  9. Laser cutting of thick sheet metals: Residual stress analysis

    Science.gov (United States)

    Arif, A. F. M.; Yilbas, B. S.; Aleem, B. J. Abdul

    2009-04-01

    Laser cutting of tailored blanks from a thick mild steel sheet is considered. Temperature and stress field in the cutting sections are modeled using the finite element method. The residual stress developed in the cutting section is determined using the X-ray diffraction (XRD) technique and is compared with the predictions. The structural and morphological changes in the cut section are examined using the optical microscopy and scanning electron microscopy (SEM). It is found that temperature and von Mises stress increase sharply in the cutting section, particularly in the direction normal to the cutting direction. The residual stress remains high in the region close to the cutting section.

  10. Nonabelian cut diagrams and their applications

    CERN Document Server

    Lam, C S

    1996-01-01

    A new kind of cut diagram is introduced to sum Feynman diagrams with nonabelian vertices. Unlike the Cutkosky diagrams which compute the discontinuity of single Feynman diagrams, the nonabelian cut diagrams represent a resummation of both the real and the imaginary parts of Feynman diagrams related by permutations. Several applications of the technique are reported, including a resolution of the apparent inconsistency of the baryon problem in large-N_c QCD, a simplified calculation of high-energy low-order QCD diagrams, and progress made with this technique on the unitarization of the BFKL equation.

  11. On Non-Abelian Symplectic Cutting

    DEFF Research Database (Denmark)

    Martens, Johan; Thaddeus, Michael

    2012-01-01

    We discuss symplectic cutting for Hamiltonian actions of non-Abelian compact groups. By using a degeneration based on the Vinberg monoid we give, in good cases, a global quotient description of a surgery construction introduced by Woodward and Meinrenken, and show it can be interpreted in algebro......-geometric terms. A key ingredient is the `universal cut' of the cotangent bundle of the group itself, which is identified with a moduli space of framed bundles on chains of projective lines recently introduced by the authors....

  12. Cut Locus Construction using Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas; Anton, François

    2011-01-01

    In this paper we present a method for appproximating cut loci for a given point p on Riemannian 2D manifolds, closely related to the notion of Voronoi diagrams. Our method finds the cut locus by advecting a front of points equally distant from p along the geodesics originating at p and finding...... the lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  13. Concrete Cutting Refinement for Crater Repair

    Science.gov (United States)

    2015-08-01

    ER D C/ G SL T R- 15 -2 9 Concrete Cutting Refinement for Crater Repair G eo te ch ni ca l a nd S tr uc tu re s La bo ra to ry...by ERDC, visit the ERDC online library at http://acwc.sdp.sirsi.net/client/default. ERDC/GSL TR-15-29 August 2015 Concrete Cutting Refinement...equipment in both soft and hard aggregate-mixed concrete . The investigated equipment included the Vermeer RW1236W and CC1531, Caterpillar SW45 and

  14. Cutting balloon angioplasty for intrastent restenosis treatment

    Directory of Open Access Journals (Sweden)

    João Orávio de Freitas Jr

    1999-05-01

    Full Text Available We describe here two patients with angiographic diagnosis of intrastent restenosis and regional myocardial ischemia. One stent restenosis was located in a native coronary artery and the other in a vein graft. Both were treated with cutting balloon angioplasty (CBA, inflated at low pressures. Angiographic success was obtained and both patients were discharged in the day after the procedure. Cutting balloon angioplasty using low inflation pressures achieved important luminal gains, in these two cases of intrastent restenosis. Further studies are necessary before the effectiveness of this procedure can be precisely defined.

  15. Recent results in mirror based high power laser cutting

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Nielsen, Jakob Skov; Elvang, Mads

    2004-01-01

    In this paper, recent results in high power laser cutting, obtained in reseach and development projects are presented. Two types of mirror based focussing systems for laser cutting have been developed and applied in laser cutting studies on CO2-lasers up to 12 kW. In shipyard environment cutting...... speed increase relative to state-of-the-art cutting of over 100 % has been achieved....

  16. A control performance analysis for MacPherson active suspension system under bounce sine sweep road profile

    Science.gov (United States)

    Ismail, M. Fahezal; Sam, Yahaya Md.; Sudin, Shahdan; Aripin, M. Khairi

    2016-10-01

    This paper studies a control performance analysis for MacPherson active suspension system. The ride comfort quality is a very important specification for modern automotive suspension system. The Proportional Integral Sliding Mode Control-Evolutionary Strategy-Composite Nonlinear Feedback (PISMC-ES-CNF) controller is designed to solve the transient problem occurred in vertical acceleration of sprung mass. The control performance is tested by using PISMC-ES-CNF and compared with Sliding Mode Controller (SMC) and Composite Nonlinear Feedback (CNF) under Bounce Sine Sweep road profile. The ISO 2631-1, 1997 is a standard for vertical acceleration of sprung mass level and degree of comfort. The one way Analysis of Variance (ANOVA) and standard deviation have showed that the PISMC- ES-CNF controller compared with others controllers achieved the best control performance.

  17. Frequency sweep of the field scattered by an inhomogeneous structure using method of moments and asymptotic waveform evaluation

    DEFF Research Database (Denmark)

    Troelsen, Jens; Meincke, Peter; Breinbjerg, Olav

    2000-01-01

    In many radar applications it is necessary to determine the scattering from an object over a wide frequency band. The asymptotic waveform evaluation (AWE), which is a moment matching (MM) technique, constitutes a method to this end. In general, MM techniques provide a reduced-order model of a fun......In many radar applications it is necessary to determine the scattering from an object over a wide frequency band. The asymptotic waveform evaluation (AWE), which is a moment matching (MM) technique, constitutes a method to this end. In general, MM techniques provide a reduced-order model...... into account. To the knowledge of the authors the AWE technique has not previously been applied to a MoM solution based on this kind of integral equation. It is the purpose of this paper to investigate the use of the AWE technique as a tool to obtain a fast frequency sweep of the field scattered...

  18. Enhanced oil recovery by surfactant-enhanced volumetric sweep efficiency: Second annual report, September 30, 1986-September 30, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J H; Scamehorn, J F

    1988-04-01

    It is widely known that heterogeneities in oil reservoirs occurring as a result of permeability variations in the rock can have a detrimental effect on an oil recovery process; preferential diversion of injected displacement fluid occurs through the high-permeability zones, leaving the lower-permeability zones at a high residual oil content at a time when it is no longer economically viable to continue the oil recovery process. A novel oil recovery process is described which aims to improve the volumetric sweep efficiency of oil recovery. High-permeability zones are partially or completely plugged off by using the chromatographic and phase behavior of surfactants and their mixtures and the preferential invasion of high-permeability areas by low-viscosity injected fluids. The plugging will divert flow into regions of higher oil saturation. 85 refs., 46 figs., 6 tabs.

  19. Optimizing the Distribution System of Fast Moving Consumer Goods Company Using Sweeping Methods with Discrete Event Simulation Approach

    Directory of Open Access Journals (Sweden)

    Rahmawan D. Arry

    2017-01-01

    Full Text Available FMCG is considered as one of the industry with the highest competition in the world. To win this industry, customer satisfaction becomes the main thing. In this paper, authors will simulate a system of distribution of goods from PT X TBK which has 3 categories, namely M1 (biscuit, M2 (powder and M3 (liquid. The distribution system has a problem on time delivery of goods which have a wide variety of obstacles, mainly on routing. There are 8 trucks with different routes and different utilization. There's trucks with over hour work and trucks with long idle time. The routing also causes problem for unused truck weight and volume capacity, where cost could possibly be reduced. Through Discrete event simulation and sweeping method, authors try to solve the problem by modelling the existing system and then find the solution to improve the distribution system and reaching the model objective.

  20. DETERMINING PLANE-SWEEP SAMPLING POINTS IN IMAGE SPACE USING THE CROSS-RATIO FOR IMAGE-BASED DEPTH ESTIMATION

    Directory of Open Access Journals (Sweden)

    B. Ruf

    2017-08-01

    Full Text Available With the emergence of small consumer Unmanned Aerial Vehicles (UAVs, the importance and interest of image-based depth estimation and model generation from aerial images has greatly increased in the photogrammetric society. In our work, we focus on algorithms that allow an online image-based dense depth estimation from video sequences, which enables the direct and live structural analysis of the depicted scene. Therefore, we use a multi-view plane-sweep algorithm with a semi-global matching (SGM optimization which is parallelized for general purpose computation on a GPU (GPGPU, reaching sufficient performance to keep up with the key-frames of input sequences. One important aspect to reach good performance is the way to sample the scene space, creating plane hypotheses. A small step size between consecutive planes, which is needed to reconstruct details in the near vicinity of the camera may lead to ambiguities in distant regions, due to the perspective projection of the camera. Furthermore, an equidistant sampling with a small step size produces a large number of plane hypotheses, leading to high computational effort. To overcome these problems, we present a novel methodology to directly determine the sampling points of plane-sweep algorithms in image space. The use of the perspective invariant cross-ratio allows us to derive the location of the sampling planes directly from the image data. With this, we efficiently sample the scene space, achieving higher sampling density in areas which are close to the camera and a lower density in distant regions. We evaluate our approach on a synthetic benchmark dataset for quantitative evaluation and on a real-image dataset consisting of aerial imagery. The experiments reveal that an inverse sampling achieves equal and better results than a linear sampling, with less sampling points and thus less runtime. Our algorithm allows an online computation of depth maps for subsequences of five frames, provided that