WorldWideScience

Sample records for boring

  1. Mind where you bore!

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    With renewable energies on the up and up, geothermal heating is becoming increasingly popular. An ardent supporter of sustainable development, CERN welcomes this trend, even though it has certain risks for the Laboratory.   More and more people in Switzerland and France are switching to geothermal heating, with the result that more and more bore holes are being sunk for geothermal probes. Since, on average, such bore holes go down to depths of 100 m they can have an impact on CERN’s underground facilities, which are also located at approximately that depth. In the Canton of Geneva, all bore holes, whatever their depth, are subject to planning permission. Applications for planning permission are granted – or refused – only after consultation with the Ground survey department (GESDEC). In France, only bore holes below a depth of 100 m require planning permission. In theory, bore holes to lesser depths simply need to be declared to the DREAL (Dire...

  2. Tsunami Bores in Kitakami River

    Science.gov (United States)

    Tolkova, Elena; Tanaka, Hitoshi

    2016-12-01

    The 2011 Tohoku tsunami entered the Kitakami river and propagated there as a train of shock waves, recorded with a 1-min interval at water level stations at Fukuchi, Iino, and the weir 17.2 km from the mouth, where the bulk of the wave was reflected back. The records showed that each bore kept its shape and identity as it traveled a 10.9-km-path Fukuchi-Iino-weir-Iino. Shock handling based on the cross-river integrated classical shock conditions was applied to reconstruct the flow velocity time histories at the measurement sites, to estimate inflow into the river at each site, to evaluate the wave heights of incident and reflected tsunami bores near the weir, and to estimate propagation speed of the individual bores. Theoretical predictions are verified against the measurements. We discuss experiences of exercising the shock conditions with actual tsunami measurements in the Kitakami river, and test applicability of the shallow-water approximation for describing tsunami bores with heights ranging from 0.3 to 4 m in a river segment with a depth of 3-4 m.

  3. Tsunami Bores in Kitakami River

    Science.gov (United States)

    Tolkova, Elena; Tanaka, Hitoshi

    2016-07-01

    The 2011 Tohoku tsunami entered the Kitakami river and propagated there as a train of shock waves, recorded with a 1-min interval at water level stations at Fukuchi, Iino, and the weir 17.2 km from the mouth, where the bulk of the wave was reflected back. The records showed that each bore kept its shape and identity as it traveled a 10.9-km-path Fukuchi-Iino-weir-Iino. Shock handling based on the cross-river integrated classical shock conditions was applied to reconstruct the flow velocity time histories at the measurement sites, to estimate inflow into the river at each site, to evaluate the wave heights of incident and reflected tsunami bores near the weir, and to estimate propagation speed of the individual bores. Theoretical predictions are verified against the measurements. We discuss experiences of exercising the shock conditions with actual tsunami measurements in the Kitakami river, and test applicability of the shallow-water approximation for describing tsunami bores with heights ranging from 0.3 to 4 m in a river segment with a depth of 3-4 m.

  4. Number of Producible and Service Well Bores on Federal Lands

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This table contains the total number of producible well bores by state as of the end of each fiscal year. A well bore is considered producible if the well bore is...

  5. Superconducting Super Collider Laboratory : tunnel boring

    CERN Document Server

    SSC Media Production

    1999-01-01

    This film will take you down into the tunnel, show you the technology involved in boring the tunnel, and show what the SSC fmeans to the U.S. in terms of scientific discovery, innovative collaborations with industry and stimulating the job base nation-wide.

  6. The possible forms of bore resistance

    Directory of Open Access Journals (Sweden)

    N. Balasubramanian

    1957-04-01

    Full Text Available A method is proposed for calculating the bore resistance of projectile by assuming as given the pressure-space curve. Applying this method to the Le Due and the isothermal systems of internal ballistics, it is shown that these systems imply certain physically in admissible features at the beginning of the motion.

  7. Tension Tests On Bored Piles In Sand

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Clausen, Johan; Damkilde, Lars

    2006-01-01

    The lengths of the bored piles varied from 2 m to 6 m and all were of a diameter of 140 mm. The piles were tested to failure in tension and the load-displacement relations were recorded. The investigation has shown pronounced differences between the load bearing capacities obtained by different...

  8. Experimental hydrodynamic study of the Qiantang River tidal bore

    Institute of Scientific and Technical Information of China (English)

    HUANG Jing; PAN Cun-hong; KUANG Cui-ping; ZENG Jian; CHEN Gang

    2013-01-01

    To study the hydrodynamics of tidal bore,a physical modeling study is carried out in a rectangular flume with considerations of the tidal bore heights,the propagation speeds,the tidal current velocities,the front steepness,and the bore shapes.After the validation with the field observations,the experimental results are analyzed,and it is shown that:(1) the greater initial ebb velocity or the larger initial water depth impedes the tidal bore propagation,(2) the maximum bore height appears at an initial ebb velocity in the range of 0.5 m/s-1.5 m/s,(3) when the Froude number exceeds 1.2,an undular bore appears,after it exceeds 1.3,a breaking bore occurs,and after it exceeds 1.7,the bore is broken.

  9. General model for boring tool optimization

    Science.gov (United States)

    Moraru, G. M.; rbes, M. V. Ze; Popescu, L. G.

    2016-08-01

    Optimizing a tool (and therefore those for boring) consist in improving its performance through maximizing the objective functions chosen by the designer and/or by user. In order to define and to implement the proposed objective functions, contribute numerous features and performance required by tool users. Incorporation of new features makes the cutting tool to be competitive in the market and to meet user requirements.

  10. The biomechanics of burrowing and boring.

    Science.gov (United States)

    Dorgan, Kelly M

    2015-01-15

    Burrowers and borers are ecosystem engineers that alter their physical environments through bioturbation, bioirrigation and bioerosion. The mechanisms of moving through solid substrata by burrowing or boring depend on the mechanical properties of the medium and the size and morphology of the organism. For burrowing animals, mud differs mechanically from sand; in mud, sediment grains are suspended in an organic matrix that fails by fracture. Macrofauna extend burrows through this elastic mud by fracture. Sand is granular and non-cohesive, enabling grains to more easily move relative to each other, and macrofaunal burrowers use fluidization or plastic rearrangement of grains. In both sand and mud, peristaltic movements apply normal forces and reduce shear. Excavation and localized grain compaction are mechanisms that plastically deform sediments and are effective in both mud and sand, with bulk excavation being used by larger organisms and localized compaction by smaller organisms. Mechanical boring of hard substrata is an extreme form of excavation in which no compaction of burrow walls occurs and grains are abraded with rigid, hard structures. Chemical boring involves secretion to dissolve or soften generally carbonate substrata. Despite substantial differences in the mechanics of the media, similar burrowing behaviors are effective in mud and sand.

  11. Undular bore theory for the Gardner equation.

    Science.gov (United States)

    Kamchatnov, A M; Kuo, Y-H; Lin, T-C; Horng, T-L; Gou, S-C; Clift, R; El, G A; Grimshaw, R H J

    2012-09-01

    We develop modulation theory for undular bores (dispersive shock waves) in the framework of the Gardner, or extended Korteweg-de Vries (KdV), equation, which is a generic mathematical model for weakly nonlinear and weakly dispersive wave propagation, when effects of higher order nonlinearity become important. Using a reduced version of the finite-gap integration method we derive the Gardner-Whitham modulation system in a Riemann invariant form and show that it can be mapped onto the well-known modulation system for the Korteweg-de Vries equation. The transformation between the two counterpart modulation systems is, however, not invertible. As a result, the study of the resolution of an initial discontinuity for the Gardner equation reveals a rich phenomenology of solutions which, along with the KdV-type simple undular bores, include nonlinear trigonometric bores, solibores, rarefaction waves, and composite solutions representing various combinations of the above structures. We construct full parametric maps of such solutions for both signs of the cubic nonlinear term in the Gardner equation. Our classification is supported by numerical simulations.

  12. Boring of full scale deposition holes using a novel dry blind boring method

    Energy Technology Data Exchange (ETDEWEB)

    Autio, J.; Kirkkomaeki, T. [Saanio and Riekkola Oy, Helsinki (Finland)

    1996-10-01

    Three holes the size of deposition holes (depth 7.5 m and diameter 1.5 m) were bored in the Research Tunnel at Olkiluoto, Finland. A novel full-face boring technique was used based on rotary crushing of rock and removal of crushed rock by vacuum flushing through the drill string. The purpose of the work was to demonstrate the feasibility of the technique. During the boring test procedures were carried out in order to determine the effect of changes in operating parameters on the performance of the boring machine and the quality of the hole. The boring method was found to be technically feasible and efficient. Evaluation of the quality of the hole included studies of the geometry of the hole, measurements of the surface roughness using a laser profilometer and study of excavation disturbances in the zone adjacent to the surface of the holes using two novel methods, He-gas diffusion and the {sup 14}C-polymethylmethacrylate methods. 43 refs.

  13. Catalog of worldwide tidal bore occurrences and characteristics

    Science.gov (United States)

    Bartsch-Winkler, S.; Lynch, David K.

    1988-01-01

    Documentation of tidal bore phenomena occurring throughout the world aids in defining the typical geographical setting of tidal bores and enables prediction of their occurrence in remote areas. Tidal bores are naturally occurring, tidally generated, solitary, moving water waves up to 6 meters in height that form upstream in estuaries with semidiurnal or nearly semidiurnal tide ranges exceeding 4 meters. Estuarine settings that have tidal bores typically include meandering fluvial systems with shallow gradients. Bores are well defined, having amplitudes greater than wind- or turbulence-caused waves, and may be undular or breaking. Formation of a bore is dependent on depth and velocity of the incoming tide and river outflow. Bores may occur in series (in several channels) or in succession (marking each tidal pulse). Tidal bores propagate up tidal estuaries a greater distance than the width of the estuary and most occur within 100 kilometers upstream of the estuary mouth. Because they are dynamic, bores cause difficulties in some shipping ports and are targets for eradication. Tidal bores are known to occur, or to have occurred in the recent past, in at least 67 localities in 16 countries at all latitudes, including every continent except Antarctica. Parts of Argentina, Canada, Central America, China, Mozambique, Madagascar, Northern Europe, North and South Korea, the United Kingdom, and the U.S.S.R. probably have additional undiscovered or unreported tidal bores. In Turnagain Arm estuary in Alaska, bores cause an abrupt increase in salinity, suspended sediment, surface character, and bottom pressure, a decrease in illumination of the water column, and a change in water temperature. Tidal bores occurring in Turnagain Arm, Alaska, have the

  14. Large Bore Powder Gun Qualification (U)

    Energy Technology Data Exchange (ETDEWEB)

    Rabern, Donald A. [Los Alamos National Laboratory; Valdiviez, Robert [Los Alamos National Laboratory

    2012-04-02

    A Large Bore Powder Gun (LBPG) is being designed to enable experimentalists to characterize material behavior outside the capabilities of the NNSS JASPER and LANL TA-55 PF-4 guns. The combination of these three guns will create a capability to conduct impact experiments over a wide range of pressures and shock profiles. The Large Bore Powder Gun will be fielded at the Nevada National Security Site (NNSS) U1a Complex. The Complex is nearly 1000 ft below ground with dedicated drifts for testing, instrumentation, and post-shot entombment. To ensure the reliability, safety, and performance of the LBPG, a qualification plan has been established and documented here. Requirements for the LBPG have been established and documented in WE-14-TR-0065 U A, Large Bore Powder Gun Customer Requirements. The document includes the requirements for the physics experiments, the gun and confinement systems, and operations at NNSS. A detailed description of the requirements is established in that document and is referred to and quoted throughout this document. Two Gun and Confinement Systems will be fielded. The Prototype Gun will be used primarily to characterize the gun and confinement performance and be the primary platform for qualification actions. This gun will also be used to investigate and qualify target and diagnostic modifications through the life of the program (U1a.104 Drift). An identical gun, the Physics Gun, will be fielded for confirmatory and Pu experiments (U1a.102D Drift). Both guns will be qualified for operation. The Gun and Confinement System design will be qualified through analysis, inspection, and testing using the Prototype Gun for the majority of process. The Physics Gun will be qualified through inspection and a limited number of qualification tests to ensure performance and behavior equivalent to the Prototype gun. Figure 1.1 shows the partial configuration of U1a and the locations of the Prototype and Physics Gun/Confinement Systems.

  15. The Bored Self in Knowledge Work

    DEFF Research Database (Denmark)

    Costas, Jana; Kärreman, Dan

    2016-01-01

    This article draws attention to reported experiences of boredom in knowledge work. Drawing on extensive qualitative data gathered at two management consultancy firms, we analyze these experiences as a particular interaction with identity regulation and work experiences. We conceptualize the reports...... of the bored self as a combination of unfilled aspirations and the sense of stagnation, leading to an arrested identity. Our contribution is to expand extant conceptualizations of employee interactions with identity regulation, in particular relating to identity work and identification. The findings provide...

  16. Key technologies of drilling process with raise boring method

    OpenAIRE

    Zhiqiang Liu(Institute of High Energy Physics); Yiping Meng

    2015-01-01

    This study presents the concept of shaft constructed by raise boring in underground mines, and the idea of inverse construction can be extended to other fields of underground engineering. The conventional raise boring methods, such as the wood support method, the hanging cage method, the creeping cage method, and the deep-hole blasting method, are analyzed and compared. In addition, the raise boring machines are classified into different types and the characteristics of each type are describe...

  17. Investigation of a mesospheric bore event over northern China

    Directory of Open Access Journals (Sweden)

    Q. Li

    2013-03-01

    Full Text Available A mesospheric bore event was observed using an OH all-sky airglow imager (ASAI at Xinglong (40.2° N, 117.4° E, in northern China, on the night of 8–9 January 2011. Simultaneous observations by a Doppler meteor radar, a broadband sodium lidar, and TIMED/SABER OH intensity and temperature measurements are used to investigate the characteristics and environment of the bore propagation and the possible relations with the Na density perturbations. The bore propagated from northeast to southwest and divided the sky into bright and dark halves. The calculations show that the bore has an average phase velocity of 68 m s−1. The crests following the bore have a horizontal wavelength of ~ 22 km. These parameters are consistent with the hydraulic jump theory proposed by Dewan and Picard, as well as the previous bore reports. Simultaneous wind measurements from the Doppler meteor radar at Shisanling (40.3° N, 116.2° E and temperature data from SABER on board the TIMED satellite are used to characterize the propagating environment of the bore. The result shows that a thermal-Doppler duct exists near the OH layer that supports the horizontal propagation of the bore. Simultaneous Na lidar observations at Yanqing (40.4° N, 116.0° E suggest that there is a downward displacement of Na density during the passage of the mesospheric bore event.

  18. A novel surface-repairing technique for gun bore

    Institute of Scientific and Technical Information of China (English)

    SU Bing; YU Xu-dong; WU Bin; WANG Cheng-tao

    2005-01-01

    A novel surface-repairing technique for gun bore was investigated, which was combined with the merits such as anti-erosion wear, damage-repairing, and etc. It was accomplished by adhering a special rare earth nanocom posite evenly to the micro-surface of gun bore. The effectiveness of this technique was approved by the target-firing using a domestic automatic rifle with chromium-coated bore. Its characteristics were discussed based on the surface analyses of the rifle bore by secondary ion mass spectrometry(SIMS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis.

  19. Intraoperative wide bore nasogastric tube knotting: A rare incidence.

    Science.gov (United States)

    Lamba, Sangeeta; Sethi, Surendra K; Khare, Arvind; Saini, Sudheendra

    2016-01-01

    Nasogastric tubes are commonly used in anesthetic practice for gastric decompression in surgical patients intraoperatively. The indications for its use are associated with a number of potential complications. Knotting of small-bore nasogastric tubes is usually common both during insertion and removal as compared to wide bore nasogastric tubes. Knotting of wide bore nasogastric tube is a rare complication and if occurs usually seen in long standing cases. We hereby report a case of incidental knotting of wide bore nasogastric tube that occurred intraoperatively.

  20. Nozzle assembly for an earth boring drill bit

    Energy Technology Data Exchange (ETDEWEB)

    Madigan, J. A.

    1985-09-24

    A nozzle assembly for an earth boring drill bit of the type adapted to receive drilling fluid under pressure and having a nozzle bore in the bottom thereof positioned closely adjacent the well bore bottom when the bit is in engagement therewith with the bore having inner and outer portions. The nozzle assembly comprises a generally cylindrical nozzle member of abrasion and erosion resistant material, selected from a plurality of such members, each being of the same outer diameter but having passaging therein of different cross-sectional area. The nozzle member is adapted to be fitted in the inner portion of the nozzle bore in sealing relationship therewith for forming a first seal for the nozzle assembly. The nozzle assembly further comprises a locknut, separate from the nozzle member, for detachbably securing the nozzle member in the nozzle bore, formed at least in part of an abrasion and erosion resistant material. The locknut has a threaded side wall engageable with the outer portion of the nozzle bore, and an aperture therethrough for enabling a stream of drilling fluid from the nozzle member to flow therethrough and being so configured in section as to receive a tool for turning the lockout to install it in and remove it from the nozzle bore.

  1. Key technologies of drilling process with raise boring method

    Institute of Scientific and Technical Information of China (English)

    Zhiqiang Liu; Yiping Meng

    2015-01-01

    This study presents the concept of shaft constructed by raise boring in underground mines, and the idea of inverse construction can be extended to other fields of underground engineering. The conventional raise boring methods, such as the wood support method, the hanging cage method, the creeping cage method, and the deep-hole blasting method, are analyzed and compared. In addition, the raise boring machines are classified into different types and the characteristics of each type are described. The components of a raise boring machine including the drill rig, the drill string and the auxiliary system are also presented. Based on the analysis of the raise boring method, the rock mechanics problems during the raise boring process are put forward, including rock fragmentation, removal of cuttings, shaft wall stability, and borehole deviation control. Finally, the development trends of raise boring technology are described as follows:(i) improve-ment of rock-breaking modes to raise drilling efficiency, (ii) development of an intelligent control tech-nique, and (iii) development of technology and equipment for nonlinear raise boring.

  2. Key technologies of drilling process with raise boring method

    Directory of Open Access Journals (Sweden)

    Zhiqiang Liu

    2015-08-01

    Full Text Available This study presents the concept of shaft constructed by raise boring in underground mines, and the idea of inverse construction can be extended to other fields of underground engineering. The conventional raise boring methods, such as the wood support method, the hanging cage method, the creeping cage method, and the deep-hole blasting method, are analyzed and compared. In addition, the raise boring machines are classified into different types and the characteristics of each type are described. The components of a raise boring machine including the drill rig, the drill string and the auxiliary system are also presented. Based on the analysis of the raise boring method, the rock mechanics problems during the raise boring process are put forward, including rock fragmentation, removal of cuttings, shaft wall stability, and borehole deviation control. Finally, the development trends of raise boring technology are described as follows: (i improvement of rock-breaking modes to raise drilling efficiency, (ii development of an intelligent control technique, and (iii development of technology and equipment for nonlinear raise boring.

  3. Formulating entompathogens for control of boring beetles in avocado orchards

    Science.gov (United States)

    A foam formulation of Beauveria bassiana was adapted to control boring beetles in avocado orchards. The two geographically independent avocado growing areas in the United States are threatened by emerging diseases vectored by boring beetles. In the California growing region, Fusarium dieback is vect...

  4. Effect of centrifugal forces on dimensional error of bored shapes

    Science.gov (United States)

    Arsuaga, M.; de Lacalle, L. N. López; Lobato, R.; Urbikain, G.; Campa, F.

    2012-04-01

    Boring operations of deep holes with a slender boring bar are often hindered by the precision because of their low static stiffness and high deformations. Because of that, it is not possible to remove much larger depths of cuts than the nose radius of the tool, unlike the case of turning and face milling operations, and consequently, the relationship between the cutting force distribution, tool geometry, feed rate and depth of cut becomes non-linear and complex. This problem gets worse when working with a rotating boring head where apart from the cutting forces and the variation of the inclination angle because of shape boring, the bar and head are affected by de centrifugal forces. The centrifugal forces, and therefore the centrifugal deflection, will vary as a function of the rotating speed, boring bar mass distribution and variable radial position of the bar in shape boring. Taking in to account all this effects, a load and deformation model was created. This model has been experimentally validated to use as a corrector factor of the radial position of the U axis in the boring head.

  5. Osedax borings in fossil marine bird bones

    Science.gov (United States)

    Kiel, Steffen; Kahl, Wolf-Achim; Goedert, James L.

    2011-01-01

    The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth's history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene.

  6. Pressure versus current scaling in a blocked bore rail gun

    Science.gov (United States)

    Barrett, B. D.; Eubank, Eric; Nunnally, W. C.

    1993-07-01

    The paper presents experimental results from a blocked bore plasma armature rail gun. A piezoelectric transducer mounted in the bore blocking structure recorded time-resolved pressures over a range of input currents from 50 to 150 kA. The bore block is located at four positions where peak current occurs for the four respective charging voltages to power the system. Problems associated with obtaining these measurements and the solutions employed are discussed. Average distances from the block face to the armature current centroid are estimated assuming a pressure balance between the magnetic and neutral pressures. The averages of the measured pressures were found to be proportional to the input current raised to the power of 1.655.

  7. Small-bore hypervelocity Electromagnetic Launcher research facility

    Science.gov (United States)

    Hurn, T. W.; Chapelle, S.; Lupan, S. P.; Holland, L.; Homeyer, W. G.; Rawls, J. M.

    1993-01-01

    A small-bore hypervelocity Electromagnetic Launcher laboratory research facility has been developed which has launched a 2-g projectile to a velocity in excess of 3.5 km/sec. This turn-key laboratory includes a 1 cm, square-bore railgun with a helium gas preaccelerator; a modular 328 kJ capacitor bank; a fiber-optically linked programmable logic control system with a graphical operator interface; a data acquisition system with current, magnetic, and projectile position diagnostics; and a flight range which provides in-flight velocity measurements and safely stops and contains the projectile. The control system fires the preaccelerator and, on receipt of an optical signal, fires the capacitor bank modules simultaneously or in a staggered mode. Armature separation and stalling limit the overall performance of the system. Changes in pulse shape and bore materials significantly improved performance. Attention is given to methods used to minimize armature separation and improve performance.

  8. Does Polishing a Rifle Bore Reduce Bullet Drag?

    Science.gov (United States)

    2012-01-17

    thus lower drag. A Remington 700 5R Mil-Spec chambered in 300 Winchester Magnum was used. The bullets used were a 155.5 grain Berger Fullbore Boat...drag on the bullets. 15. SUBJECT TERMS Ballistic coefficient, aerodynamic drag, rifle bore, bore polishing, Remington 700 5R 16. SECURITY...A Remington 700 5R Mil-Spec chambered in 300 Winchester Magnum was used. The bullets used were a 155.5 grain Berger Fullbore Boat Tail and a 125

  9. Melioidosis from contaminated bore water and successful UV sterilization.

    Science.gov (United States)

    McRobb, Evan; Kaestli, Mirjam; Mayo, Mark; Price, Erin P; Sarovich, Derek S; Godoy, Daniel; Spratt, Brian G; Currie, Bart J

    2013-08-01

    Two cases of melioidosis at a residence in rural northern Australia were linked to the unchlorinated domestic bore (automated well) water supply, which was found to have a high concentration of Burkholderia pseudomallei. Using multilocus sequence typing, clinical B. pseudomallei isolates from both cases were identical to an isolate from the bore water supply. A simple UV sterilizer reduced B. pseudomallei from the domestic water supply to undetectable levels. We have shown that UV treatment is highly effective for remediation of water contaminated with B. pseudomallei and recommend its consideration in households where individuals may be at heightened risk of contracting melioidosis.

  10. Rational Distribution of Heat Loss in Well Bore

    Institute of Scientific and Technical Information of China (English)

    Li Jingqin; Chen Yanhua; Xiang Xinyao

    1996-01-01

    @@ Introduction It is not easy to produce viscous crude because of its heavy viscosity. At present, viscous crude is mainly recovered by thermal recovery, i.e. by steam injection. In the course of steam injection, heat loss, especially that in well bore has a direct influence on thermal productive effectiveness.

  11. Slime thickness evaluation of bored piles by electrical resistivity probe

    Science.gov (United States)

    Chun, Ok-Hyun; Yoon, Hyung-Koo; Park, Min-Chul; Lee, Jong-Sub

    2014-09-01

    The bottoms of bored piles are generally stacked with soil particles, both while boreholes are being drilled, and afterward. The stacked soils are called slime, and when loads are applied on the pile, increase the pile settlement. Thus to guarantee the end bearing capacity of bored piles, the slime thickness should be precisely detected. The objective of this study is to suggest a new method for evaluating the slime thickness, using temperature compensated electrical resistivity. Laboratory studies are performed in advance, to estimate and compare the resolution of the electrical resistivity probe (ERP) and time domain reflectometry (TDR). The electrical properties of the ERP and TDR are measured using coaxial type electrodes and parallel type two-wire electrodes, respectively. Penetration tests, conducted in the fully saturated sand-clay mixtures, demonstrate that the ERP produces a better resolution of layer detection than TDR. Thus, field application tests using the ERP with a diameter of 35.7 mm are conducted for the investigation of slime thickness in large diameter bored piles. Field tests show that the slime layers are clearly identified by the ERP: the electrical resistivity dramatically increases at the interface between the slurry and slime layer. The electrical resistivity in the slurry layer inversely correlates with the amount of circulated water. This study suggests that the new electrical resistivity method may be a useful method for the investigation of the slime thickness in bored piles.

  12. Research on Valve Body Design of Large Bore Sodium Valve

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Large bore sodium valve is one kind of key equipments of China Demonstration Fast Reactor (CDFR). It is installed in the pipeline before and behind SG units as a locking mechanism. Valve body which is used to bear pressure is the core of sodium valve design.

  13. CNLC Provides Well-Bore Technical Services Worldwide

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ BRIEF INTRODUCTION of CNLC China National Logging Corporation (CNLC), a subsidiary of CNPC Services & Engineering Ltd.,which provides well bore technical services at international market solely on behalf of CNPC, is a specialized service company mainly engaged in: 1. Wire-line logging, mud logging, well testing,well completion, perforating and other relevant engineering services.

  14. Determination of Muzzle Velocity Loss by Bore Wear Pattern

    Institute of Scientific and Technical Information of China (English)

    LIU Yi-xin; WANG Gui-yu

    2007-01-01

    A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore, it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity loss. It has been applied to a national military standard since July 1, 2004.

  15. Quality Designed Twin Wire Arc Spraying of Aluminum Bores

    Science.gov (United States)

    König, Johannes; Lahres, Michael; Methner, Oliver

    2015-01-01

    After 125 years of development in combustion engines, the attractiveness of these powerplants still gains a great deal of attention. The efficiency of engines has been increased continuously through numerous innovations during the last years. Especially in the field of motor engineering, consequent friction optimization leads to cost-effective fuel consumption advantages and a CO2 reduction. This is the motivation and adjusting lever of NANOSLIDE® from Mercedes-Benz. The twin wire arc-spraying process of the aluminum bore creates a thin, iron-carbon-alloyed coating which is surface-finished through honing. Due to the continuous development in engines, the coating strategies must be adapted in parallel to achieve a quality-conformed coating result. The most important factors to this end are the controlled indemnification of a minimal coating thickness and a homogeneous coating deposition of the complete bore. A specific system enables the measuring and adjusting of the part and the central plunging of the coating torch into the bore to achieve a homogeneous coating thickness. Before and after measurement of the bore diameter enables conclusions about the coating thickness. A software tool specifically developed for coating deposition can transfer this information to a model that predicts the coating deposition as a function of the coating strategy.

  16. Acoustic Monitoring for Tunnel Boring in Soft Soils

    NARCIS (Netherlands)

    Swinnen, G.

    2003-01-01

    The TBM, not a blind mole! This thesis deals with some aspects of seismic imaging of the soft soil in front of a Tunnel Boring Machine to help tunnel constructors ``see'' the subsurface they are approaching, instead of steering the TBM forward like a ``blind mole''. The Dutch shallow subsurface has

  17. INTERNAL TIDES, SOLITARY WAVES AND BORES IN SHALLOW SEAS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Remote sensing and in situ observations of internal tides, solitary waves and bores in shallow water are briefly reviewed in this paper. The emphasis is laid on interpreting SAR images based on oceanographic measurements, and analyzing characteristics of internal waves in the China Seas. Directions for future research are discussed.

  18. Thermal modeling of bore fields with arbitrarily oriented boreholes

    Science.gov (United States)

    Lazzarotto, Alberto

    2016-04-01

    The accurate prediction of the thermal behavior of bore fields for shallow geothermal applications is necessary to carry out a proper design of such systems. A classical methodology to perform this analysis is the so-called g-function method. Most commercial tools implementing this methodology are designed to handle only bore fields configurations with vertical boreholes. This is a limitation since this condition might not apply in a real installation. In a recent development by the author, a semi-analytical method to determine g-function for bore fields with arbitrarily oriented boreholes was introduced. The strategy utilized is based on the idea introduced by Cimmino of representing boreholes as stacked finite line sources. The temperature along these finite lines is calculated by applying the superposition of the effects of each linear heat source in the field. This modeling technique allows to approximate uneven heat distribution along the boreholes which is a key feature for the calculation of g-functions according to Eskilson's boundary conditions. The method has been tested for a few simple configurations and showed results that are similar compare to previous results computed numerically by Eskilson. The method has been then successfully applied to the g-function calculation of an existing large scale highly asymmetrical bore field.

  19. Number of Well Bores Started (Spud) During the Fiscal Year on Federal Lands

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This table contains the total number of well bores started (spudded), by state, during each fiscal year. "Spudding in," or to "spud" a well bore, means to begin...

  20. Speed Regulator for Permanent Magnet DC Boring Machine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper a variable-speed system for a loaded permanent magnet direct current boring machine (PMDCBM) is described in details. The voltage adjustment of PMDCBM is accomplished by means of solid state switch with a high gain Darlington transistor. The device designed possesses good variable speed characteristic and Iow loss at low speed. The speed can be regulated automatically to hold at an ideal value according to the load.

  1. The propagation of internal undular bores over variable topography

    Science.gov (United States)

    Grimshaw, R.; Yuan, C.

    2016-10-01

    In the coastal ocean, large amplitude, horizontally propagating internal wave trains are commonly observed. These are long nonlinear waves and can be modelled by equations of the Korteweg-de Vries type. Typically they occur in regions of variable bottom topography when the variable-coefficient Korteweg-de Vries equation is an appropriate model. Of special interest is the situation when the coefficient of the quadratic nonlinear term changes sign at a certain critical point. This case has been widely studied for a solitary wave, which is extinguished at the critical point and replaced by a train of solitary waves of the opposite polarity to the incident wave, riding on a pedestal of the original polarity. Here we examine the same situation for an undular bore, represented by a modulated periodic wave train. Numerical simulations and some asymptotic analysis based on Whitham modulation equations show that the leading solitary waves in the undular bore are destroyed and replaced by a developing rarefaction wave supporting emerging solitary waves of the opposite polarity. In contrast the rear of the undular bore emerges with the same shape, but with reduced wave amplitudes, a shorter overall length scale and moves more slowly.

  2. In-Situ Test and Numerical Analysis of Bore Pressure on Sheet-Pile Groin

    Institute of Scientific and Technical Information of China (English)

    XU Chang-jie; CAI Yuan-qiang; XUAN Wei-li; CHEN Hai-jun; SONG Yang

    2006-01-01

    An in-situ test of bore pressure on a sheet-pile groin is carried out to investigate the characteristics of the bore pressure of tide in the Qian-tang River. The histories of bore pressure and the rule of the distribution of bore pressure on the sheet-pile groin are obtained through the test, which shows that the bore pressure on the sheet-pile groin are varies with time and space. The peak value of bore pressure on sheet-pile groin at different heights occurs almost at the same time. The vertical distribution of bore pressure on the sheet-pile groin is linear above the still water level. The maximum bore pressure on the sheet-pile groin occurs at the still water level. Then a numerical method is also used to further study the characteristics of bore pressure. The standard κ-ε turbulence model and VOF (volume of fluid) method for surface tracking are used to simulate the bore against the sheet-pile groin. The numerical results show flow fields, the position of free surface and time history and spatial distribution of bore pressure on the sheet-pile groin. The numerical and test results show good agreement.

  3. A new method for boring of non-circular holes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Kai; HU De-jin

    2006-01-01

    A revolving electromagnetic actuation mechanism composed of an electromagnetic stator and an electromagnetic rotor has been developed for boring non-circular holes.The main component of the rotor is a flexure-hinged based flexible body.There are four pole-pair coils in the stator supplying actuation currents.The micro-displacement between the stator and rotor can be controlled by changing the currents applied in the pole-pair coils.Through linearization of the actuation force near the static action point,a linear relationship between the control current and the actuation force was established,and the synchronizing control method of the electromagnetic actuation mechanism is presented here.With two-factor analysis of the linearization error of the actuation force,the influences of control current and micro-displacement to the linearization error of the actuation force were studied.Then,the principle for designing the basic parameters of the magnetic actuation mechanism is put forward.The calibration of the mechanism indicates that the relationship between the micro-displacement of the rotor and the control current has linear characteristics in the required micro-displacement range.Simulation tests show that the turning radius of the rotor changes with the control current.The proposed mechanism can feasibly supply a controllable micro displacement to the boring bar.

  4. Gun bore flaw image matching based on improved SIFT descriptor

    Science.gov (United States)

    Zeng, Luan; Xiong, Wei; Zhai, You

    2013-01-01

    In order to increase the operation speed and matching ability of SIFT algorithm, the SIFT descriptor and matching strategy are improved. First, a method of constructing feature descriptor based on sector area is proposed. By computing the gradients histogram of location bins which are parted into 6 sector areas, a descriptor with 48 dimensions is constituted. It can reduce the dimension of feature vector and decrease the complexity of structuring descriptor. Second, it introduce a strategy that partitions the circular region into 6 identical sector areas starting from the dominate orientation. Consequently, the computational complexity is reduced due to cancellation of rotation operation for the area. The experimental results indicate that comparing with the OpenCV SIFT arithmetic, the average matching speed of the new method increase by about 55.86%. The matching veracity can be increased even under some variation of view point, illumination, rotation, scale and out of focus. The new method got satisfied results in gun bore flaw image matching. Keywords: Metrology, Flaw image matching, Gun bore, Feature descriptor

  5. Turbulent mixing and wave radiation in non-Boussinesq internal bores

    DEFF Research Database (Denmark)

    Borden, Zac; Koblitz, Tilman; Meiburg, Eckart

    2012-01-01

    ratio, defined as the ratio of the density of the lighter fluid to the heavier fluid, is greater than approximately one half. For smaller density ratios, undular waves generated at the bore's front dominate over the effects of turbulent mixing, and the expanding layer loses energy across the bore. Based...... on our results, we show that if one can predict the amount of energy radiated by bores through undular waves, it is possible to derive an accurate model for the propagation of non-Boussinesq bores. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4745478]...

  6. TRANSMISSION BEHAVIOR OF MUD-PRESSURE PULSE ALONG WELL BORE

    Institute of Scientific and Technical Information of China (English)

    LIU Xiu-shan; LI Bo; YUE Yu-quan

    2007-01-01

    In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was considered to be a single-phase fluid through which the mud pulses travel, despite the fact that the drilling mud is composed of two or more phases. In this article, a multiphase flow formula was proposed to calculate the mud-pulse velocity as mud solids and free-gas content change, and a mathematical model was put forward to simulate the dynamic-transmission behavior of the mud-pressure pulse or waves. Compared to conventional methods, the present model provides more accurate mud-pulse attenuation, and the dynamic-transmission behavior of drilling-mud pulses along well bores can also be easily examined. The model is valuable in improving the existing mud-pulse systems and developing new drilling-mud pulse systems.

  7. Deep bore hole instrumentation along San Francisco Bay Bridges

    Energy Technology Data Exchange (ETDEWEB)

    Bakun, W.; Bowman, J.; Clymer, R.; Foxall, W.; Hipley, P.; Hollfelder, J.; Hutchings, L.; Jarpe, S.; Kasameyer, P.; McEvilly, T.; Mualchin, L.; Palmer, M.

    1998-10-01

    The Bay Bridges down hole network consists of sensors in bore holes that are drilled 100 ft. into bedrock around and in the San Francisco Bay. Between 2 and 8 instruments have been spaced along the Dumbarton, San Mateo, Bay, and San Rafael bridges. The instruments will provide multiple use data that is important to geotechnical, structural engineering, and seismological studies. The holes are between 100 and 1000 ft deep and were drilled by Caltrans. There are twenty- one sensor packages at fifteen sites. Extensive financial support is being contributed by Caltrans, UCB, LBL, LLNL-LDRD, U.C. Campus/Laboratory Collaboration (CLC) program, and USGS. The down hole instrument package contains a three component HS-1 seismometer and three orthogonal Wilcox 73 1 accelerometers, and is capable of recording a micro g from local M = 1.0 earthquakes to 0.5 g strong ground motion form large Bay Area earthquakes.

  8. An introduction to RAM analysis of EPB tunnel boring machine

    Directory of Open Access Journals (Sweden)

    Hasel Amini Khoshalan

    2014-03-01

    Full Text Available Earth pressure balance tunnel boring machines (EPB - TBMs are favorably used in construction of tunnels in urban areas. These more expensive machines with high operational costs require an exclusive study and knowledge on these machine components and subsystems and their failure and downtimes for time planning, cost control and performance prediction with a high accuracy. Thus guidelines for reliability, availability and maintainability (RAM analysis of an EPB machine are completely expressed. Gathering and recording all daily failure and repair times and other maintenance tasks, dividing the machine into subsystems (including mechanical subsystem, electrical subsystem, hydraulic subsystem, pneumatic subsystem and water subsystem, graphical tests (trend test and correlation test, statistical tests and analysis are discussed in detail.

  9. Looking ahead of a tunnel boring machine with 2-D SH full waveform inversion

    NARCIS (Netherlands)

    Pisupati, P.B.; Mulder, W.A.; Drijkoningen, G.G.; Reijnen, R.

    2015-01-01

    In the near-surface with unconsolidated soils, shear properties can be well imaged, sometimes better than P-wave properties. To facilitate ground prediction ahead of a tunnel boring machine (TBM), active ‘surveys’ with shear-wave vibrators are carried out during boring. In such surveys, only a few s

  10. Method and apparatus for completing a non-vertical portion of a subterranean well bore

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, J.F.; Spatz, E.C.; Salerni, J.V.; Peterson, E.R.; Weirich, J.B.

    1989-09-19

    This patent describes an apparatus for completing a well bore having a deviated configuration including an essentially vertical entry portion communicating with a curved portion extending away from the top surface of the well and communicating with a generally linear bore portion traversable with a production formation. It comprises: a plurality of tubular screen elements; a plurality of tubular stabilizer housings threadably interconnecting the tubular screen elements, thereby forming a tool string; means for securing the stabilizer elements in a radially retracted position during run-in of the screen elements into the generally linear portion of the well bore; and fluid pressure means for radially expanding the stabilizer elements into engagement with the wall of the generally linear portion of the well bore, thereby centering the tubular screen elements relative to the generally linear portion of the well bore. The method of completing a deviated subterranean well bore having a generally vertical entry portion and a nonvertical bore portion traversing a production formation. It comprises the steps of: inserting in the non-vertical well portion a plurality of tubular screen elements interconnected by tubular stabilizing housings; each stabilizer housing mounting a plurality of peripherally spaced, radially shiftable stabilizer elements; and placing the stabilizer elements in a radially retracted position during run in. The stabilizer elements being movable from retracted position and movable radially outwardly to engage the well bore when the tubular screen elements are positioned in the production formation.

  11. 46 CFR 148.04-13 - Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel).

    Science.gov (United States)

    2010-10-01

    .... Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel) must not be stowed and... 46 Shipping 5 2010-10-01 2010-10-01 false Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel). 148.04-13 Section 148.04-13 Shipping COAST GUARD, DEPARTMENT OF...

  12. Boring sponges (Porifera, Clionidae) collected during the "Tydeman" Canary Islands expedition Cancap-II, 1977

    NARCIS (Netherlands)

    Groot, de R.A.

    1980-01-01

    INTRODUCTION AND MATERIAL The boring sponges of the Canary Islands have never been studied in any detail, but the boring fauna of this archipelago cannot be expected to be very rich. All islands are volcanic and calcareous rocks are not common. Consequently, in most areas large shells and rhodophyte

  13. Ten Years of bored tunnels in the Netherlands: Part I: Geotechnical issues

    NARCIS (Netherlands)

    Bakker, K.J.; Bezuijen, A.

    2008-01-01

    Ten years have passed since in 1997 for the first time construction of bored tunnels in the Netherlands soft soil was undertaken. Before that date essentially only immersed tunnels and cut-and-cover tunnels were constructed in the Netherlands. The first two bored tunnels were Pilot Projects, the 2nd

  14. Boring crustaceans damage polystyrene floats under docks polluting marine waters with microplastic.

    Science.gov (United States)

    Davidson, Timothy M

    2012-09-01

    Boring isopods damage expanded polystyrene floats under docks and, in the process, expel copious numbers of microplastic particles. This paper describes the impacts of boring isopods in aquaculture facilities and docks, quantifies and discusses the implications of these microplastics, and tests if an alternate foam type prevents boring. Floats from aquaculture facilities and docks were heavily damaged by thousands of isopods and their burrows. Multiple sites in Asia, Australia, Panama, and the USA exhibited evidence of isopod damage. One isopod creates thousands of microplastic particles when excavating a burrow; colonies can expel millions of particles. Microplastics similar in size to these particles may facilitate the spread of non-native species or be ingested by organisms causing physical or toxicological harm. Extruded polystyrene inhibited boring, suggesting this foam may prevent damage in the field. These results reveal boring isopods cause widespread damage to docks and are a novel source of microplastic pollution.

  15. Method for completing a non-vertical portion of a subterranean well bore

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, J.F.; Spatz, E.C.; Salerni, J.V.; Peterson, E.R.; Weirich, J.B.

    1990-04-10

    This patent describes a method of completing a well bore having a deviated configuration including an entry portion communicating with a curved portion extending downwardly in the well from the entry portion and a generally linear end portion traversable with a production formation. It comprises: forming a conduit including well isolation means, at least one screen element and at least one stabilizer means having at least one movable stabilizer portion movable from a first retracted position to a second expanded position; running the conduit into the well bore and manipulating the conduit to facilitate passage of the conduit through the curved portion of the well bore; setting the well isolation means to position the tubular screen means approximate the linear portion of the well bore; and actuating the stabilizer members to the second expanded position to engage the adjacent wall of the well bore and position the screen means away from the adjacent wall.

  16. Seismic monitoring experiment of raise boring in 2014

    Energy Technology Data Exchange (ETDEWEB)

    Saari, J.; Malm, M. [AaF-Consult Oy, Espoo (Finland)

    2015-01-15

    In Olkiluoto, Posiva Oy has operated a local seismic network since February 2002. The purpose of the microearthquake measurements at Olkiluoto is to improve understanding of the structure, behaviour and long term stability of the bedrock. The studies include both tectonic and excavation-induced microearthquakes. An additional task of monitoring is related to safeguarding of ONKALO. The possibility to excavate an illegal access to ONKALO has been concerned when the safeguards are discussed. Therefore all recorded explosions in the Olkiluoto area and in ONKALO are located. If a concentration of explosions is observed, the origin of that is found out. Also a concept of hidden illegal explosions, detonated at the same time as the real excavation blasts, has been examined. According to the experience gained in Olkiluoto, it can be concluded that, as long the seismic network is in operation and the results are analysed by a skilled person, it is practically impossible to do illegal undetected excavation by blasting within the Olkiluoto seismic network area. In this report a possibility of seismic monitoring of undeclared excavation done by tunnel boring machine (TBM) has been investigated. In the earlier investigations the instruments were at the ground surface and the sensors were triaxial short period (1 Hz) geophones or broadband geophones. The characteristics (frequency content, polarity and amplitude) of the continuous seismic vibration generated by TMB were studied. The onset time of the seismic signal were not distinguished. Altogether 16 new 10 kHz accelerometers were installed in boreholes inside ONKALO March 2012. The sensors comprised a new subnetwork that monitored the raise boring of two shafts done 2014, from the level -455 m to the level -290 m. The aim was to record the seismic signal generated when the drill bit hits the rock at the moment the tunnel boring begins. Altogether 113 seismic signals generated by the drill bit were located during the

  17. Continuous circulation apparatus for air drilling well bore operations

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, J.L.

    1982-02-16

    An apparatus is disclosed for maintaining a continuous supply of air pressure downhole during a well bore drilling operation, even during the addition of a pipe section to the drill string. It consists of a housing installed at the surface of the well at the position of the drilling equipment wherein the upper end of the drill string is separated from the drive mechanism in order that a new piece of drill pipe may be added to the drill string, a flapper or closure member pivotally secured within the housing normally held in an open position by the outer periphery of the drill string and spring urged in a direction toward the open end of the sleeve through which the drive mechanism passes when the drive mechanism has been backed off or removed for the addition of a section of pipe to the drill string, and a by-pass line in communication with the interior of the housing for directing air pressure from the air supply to the housing when the flapper member is in the closed position whereby the air pressure may be circulated downwardly through the drill string for maintaining the air circulation downhole during the entire drilling operation.

  18. Ecology of the wood-boring bivalve Martesia striata (Pholadidae) in Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Yennawar, P.L.; Thakur, N.L.; Anil, A.C.; Venkat, K.; Wagh, A.B.

    Martesia striata is one of the dominant wood-boring organisms found in Indian waters. Incidence of this organism in the Zuari estuary (Goa) was evaluated by exposing wooden panels (Mangifera indica) to the marine environment between January 1996...

  19. Effect of fluid viscosity on wave propagation in a cylindrical bore in micropolar elastic medium

    Indian Academy of Sciences (India)

    Sunita Deswal; Sushil K Tomar; Rajneesh Kumar

    2000-10-01

    Wave propagation in a cylindrical bore filled with viscous liquid and situated in a micropolar elastic medium of infinite extent is studied. Frequency equation for surface wave propagation near the surface of the cylindrical bore is obtained and the effect of viscosity and micropolarity on dispersion curves is observed. The earlier problems of Biot and of Banerji and Sengupta have been reduced as a special case of our problem.

  20. Solid-to-hybrid transitioning armature railgun with non-conforming-to-prejudice bore profile

    Science.gov (United States)

    Solberg, Jerome Michael

    2012-12-04

    An improved railgun, railgun barrel, railgun projectile, and railgun system for accelerating a solid-to-hybrid transitioning armature projectile using a barrel having a bore that does not conform to a cross-sectional profile of the projectile, to contact and guide the projectile only by the rails in a low pressure bore volume so as to minimize damage, failure, and/or underperformance caused by plasma armatures, insulator ablation, and/or restrikes.

  1. A Multi-Instrument Measurement of a Mesospheric Bore at the Equator

    Science.gov (United States)

    Shiokawa, K.; Suzuki, S.; Otsuka, Y.; Ogawa, T.; Nakamura, T.; Mlynczak, M. G.; Russell, J. M., III

    2005-01-01

    We have made a comprehensive measurement of mesospheric bore phenomenon at the equator at Kototabang, Indonesia (0.2 deg S, 100.3 deg E), using an airglow imager, an airglow temperature photometer, a meteor radar, and the SABER instrument on board the TIMED satellite. The bore was detected in airglow images of both OH-band (peak emission altitude: 87 km) and 557.7-nm (96 km) emissions, as east-west front-like structure propagating northward with a velocity of 52-58 m/s. Wave trains with a horizontal wavelength of 30-70 km are observed behind the bore front. The airglow intensity decreases for all the mesospheric emissions of OI (557.7 nm), OH-band, O2-band (altitude: 94 km), and Na (589.3 nm) (90 km) after the bore passage. The rotational temperatures of both OH-band and O2-band also decrease approximately 10 K after the bore passage. An intense shear in northward wind velocity of 80m/s was observed at altitudes of 84-90 km by the meteor radar. Kinetic temperature profile at altitudes of 20-120 km was observed near Kototabang by TIMED/SABER. On the basis of these observations, we discuss generation and ducting of the observed mesospheric bore.

  2. An undular bore solution for the higher-order Korteweg-de Vries equation

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, T R [School of Mathematics and Applied Statistics, University of Wollongong, Wollongong, 2522, NSW (Australia); Smyth, N F [School of Mathematics, University of Edinburgh, The King' s Buildings, Mayfield Road, Edinburgh, EH9 3JZ (United Kingdom)

    2006-09-15

    Undular bores describe the evolution and smoothing out of an initial step in mean height and are frequently observed in both oceanographic and meteorological applications. The undular bore solution for the higher-order Korteweg-de Vries (KdV) equation is derived, using an asymptotic transformation which relates the KdV equation and its higher-order counterpart. The higher-order KdV equation considered includes all possible third-order correction terms (where the KdV equation retains second-order terms). The asymptotic transformation is then applied to the KdV undular bore solution to obtain the higher-order undular bore. Examples of higher-order undular bores, describing both surface and internal waves, are presented. Key properties, such as the amplitude and speed of the lead soliton and the width of the bore, are found. An excellent comparison is obtained between the analytical and numerical solutions. Also, it is illustrated how an asymptotic transformation and numerical solutions can be combined to generate hybrid asymptotic-numerical solutions, thus avoiding the severe instabilities associated with numerical schemes for the higher-order KdV equation. (letter to the editor)

  3. A preliminary study of the turbulence features of the tidal bore in the Qiantang River, China

    Institute of Scientific and Technical Information of China (English)

    谢东风; 潘存鸿

    2013-01-01

    In this paper, the turbulence characteristics of the tidal flow in the Qiantang River, China, the world-famous Qiantang bore, are studied. A detailed field observation at the Yanguan section of the Qiantang River was carried out during the spring tide in October 2010 with a continuous collection of high frequency turbulence data. The data analysis shows that the hydrodynamic processes are characterized by a strong tidal bore. Statistics of the turbulence such as the probability distributions of the turbulent components, the variance terms and the covariance terms are found consistent with those of previous studies of estuaries without the tidal bore. However, along the vertical profile, the distributions of all variables become more scattered downwards. The horizontal turbulence fluctuations are of a similar magnitude while the vertical turbulence has a fluctuation magnitude about 1/3 of that of the horizontal turbulences. The fluctuation strengths and the Reynolds stresses are much larger than those of other estuaries when the bore arrives. The bottom shear stress varies periodically with the tides, less than 0.44 N/m2 during the ebb but is increased drastically at the bore arrival, with the maximum being 0.92 N/m2. A good linear relationship is found between the bottom shear stress and the bottom suspended sediment concentration.

  4. Armor Development from Decapitated Flash Flood Bores in Supply-Limited Flume Experiments

    Science.gov (United States)

    Goodwin, K.; Rhodes, R.; Johnson, J. P.

    2013-12-01

    In rivers assumed to have quasi-normal flow, three main processes have been used to explain bed surface armoring: i) selective entrainment and transport of smaller grains, ii) limited supply of smaller grain sizes, and iii) equal mobility of grains of different sizes, which develops through natural feedbacks such that larger, less mobile grains are enriched on the surface relative to smaller grains. Flash flood-dominated river channels in arid environments often completely lack surface armoring, yet it is unclear whether increased sediment supply or transport of all grain sizes prevents armor development. In order to examine armor development in an end-member case of non-normal flow, we conducted a series of laboratory experiments using flash flood bores. The flume is 33.5 m long, 0.5 m wide, 0.8 m tall, and capable of creating reproducible flood bores by raising a high-speed computerized lift gate and releasing impounded water. For each experiment, the gate was quickly lowered as soon as the flood bore traveled the length of the flume, 'decapitating' the bore from subsequent flow, to better isolate the effects of the bore alone on entrainment and transport. Sediment was not fed into the upstream end of the flume and only sourced from the gravel bed (2 mm to 40 mm), resulting in supply-limited experimental conditions. In response to repeated flood bores, the surface grain size distribution rapidly coarsened. We interpret that kinetic sieving was the dominant cause of surface armoring in these experiments. LiDAR scans of the bed topography from before and after each bore show increased surface roughness due to grain size changes, but small surface elevation changes due to relatively limited erosion. Digital gravelometry from photographs taken after each bore show increased armoring, while sediment transported out the downstream end of the flume tended to be as coarse or coarser than the bed surface. Travel distances of three sizes of RFID-tagged tracer clasts show

  5. Estimation of the equilibrium formation temperature in the presence of bore fluid invasion

    DEFF Research Database (Denmark)

    Poulsen, Søren Erbs; Nielsen, S.B.; Balling, N.

    2012-01-01

    Bottom hole temperatures (BHTs) measured during drilling operations are thermally disturbed by the drilling process. This paper presents a method, CSMI (Cylindrical Source Model with Invasion of bore mud filtrate), for estimating equilibrium formation temperatures with probability distributions...... the possibility of invasion (advection) of mud filtrate into the formation. In a synthetic example, it is demonstrated that given bore fluid invasion and a low and high temperature of the bore mud and formation, respectively, the equilibrium formation temperature and the uncertainty hereon is underestimated...... with the CSMI scheme. The analysis of five BHT records measured onshore Denmark, for which the equilibrium formation temperature is known, shows that CSMI temperatures based on single datum records are highly uncertain because of a strong negative coupling between the temperature of the mud filtrate...

  6. Solitons, compactons and undular bores in Benjamin–Bona–Mahony-like systems

    Indian Academy of Sciences (India)

    APARNA SAHA; B TALUKDAR; UMAPADA DAS; SUPRIYA CHATTERJEE

    2017-02-01

    We examine the effect of dissipation on travelling waves in nonlinear dispersive systems modelled by Benjamin–Bona–Mahony (BBM)-like equations. In the absence of dissipation, the BBM-like equations are found to support soliton and compacton/anticompacton solutions depending on whether the dispersive term islinear or nonlinear. We study the influence of increasing nonlinearity of the medium on the soliton and compacton dynamics. The dissipative effect is found to convert the solitons either to undular bores or to shock-like waves depending on the degree of nonlinearity of the equations. The anticompacton solutions are also transformed to undular bores by the effect of dissipation. But the compactons tend to vanish due to viscous effects. The local oscillatory structures behind the bores and/or shock-like waves in the case of solitons and anticompactons are found to depend sensitively both on the coefficient of viscosity and solution of the unperturbed problem.

  7. Observation of Optical Undular Bores in Multiple Four-Wave Mixing

    Science.gov (United States)

    Fatome, J.; Finot, C.; Millot, G.; Armaroli, A.; Trillo, S.

    2014-04-01

    We demonstrate that wave-breaking dramatically affects the dynamics of nonlinear frequency conversion processes that operate in the regime of high efficiency (strong multiple four-wave mixing). In particular, by exploiting an all-optical-fiber platform, we show that input modulations propagating in standard telecom fibers in the regime of weak normal dispersion lead to the formation of undular bores (dispersive shock waves) that mimic the typical behavior of dispersive hydrodynamics exhibited, e.g., by gravity waves and tidal bores. Thanks to the nonpulsed nature of the beat signal employed in our experiment, we are able to clearly observe how the periodic nature of the input modulation forces adjacent undular bores to collide elastically.

  8. In-bore setup and Software for 3T MRI-guided Transperineal Prostate Biopsy

    Science.gov (United States)

    Tokuda, Junichi; Tuncali, Kemal; Iordachita, Iulian; Song, Sang-Eun; Fedorov, Andriy; Oguro, Sota; Lasso, Andras; Fennessy, Fiona M; Tempany, Clare M; Hata, Nobuhiko

    2012-01-01

    MRI-guided prostate biopsy in conventional closed-bore scanners requires transferring the patient outside the bore during needle insertion due to the constrained in-bore space, causing a safety hazard and limiting image feedback. To address this issue, we present our custom-made in-bore setup and software to support MRI-guided transperineal prostate biopsy in a wide-bore 3 Tesla (T) MRI scanner. The setup consists of a specially designed tabletop and a needle-guiding template with Z-frame that give a physician access to the perineum of the patient at the imaging position and allow performance of MRI-guided transperineal biopsy without moving the patient out of the scanner. The software and Z-frame allow registration of the template, target planning, and biopsy guidance. Initially, we performed phantom experiments to assess the accuracy of template registration and needle placement in a controlled environment. Subsequently, we embarked on our clinical trial (N = 10). The phantom experiments showed that the translational errors of the template registration along the right-left (RP) and anterior-posterior (AP) axes were 1.1 ± 0.8 mm and 1.4 ± 1.1 mm respectively, while the rotational errors around the RL, AP, and superior-inferior axes were 0.8 ± 1.0 degrees, 1.7 ± 1.6 degrees, and 0.0 ± 0.0 degrees respectively. The 2D root-mean-square (RMS) needle placement error was 3.0 mm. The clinical biopsy procedures were safely carried out in all ten clinical cases with a needle placement error of 5.4 mm (2D RMS). In conclusion, transperineal prostate biopsy in a wide-bore 3T scanner is feasible using our custom-made tabletop set up and software, which supports manual needle placement without moving the patient out of the magnet. PMID:22951350

  9. The Effects of Guide Pads on Bore Diameter Enlargement Magnitude in Deep Hole Drilling

    Directory of Open Access Journals (Sweden)

    Zhang Huang

    2016-01-01

    Full Text Available Deep hole machining accuracy plays a crucial role in product’s quality. The results of an investigation into the machining accuracy of deep drilling holes which highlights problems of bore diameter enlargement magnitude assessment are presented in this paper. Through the study of BTA deep drilling tool properties and mechanism, as well as the formation rule of deep hole surface, clarified the burnishing mechanism of guide pad in deep hole drilling, and obtained the directly relationship between surface formation rule and the guide pad. After drilling experimentrevealed the effect of guide pad on bore diameter enlargement magnitude.

  10. Flexible small-bore hollow fibers with an inner polymer coating.

    Science.gov (United States)

    Abe, Y; Shi, Y W; Matsuura, Y; Miyagi, M

    2000-02-01

    Flexible hollow-glass fibers with small-bore diameters of 250 and 320 mum have been developed for Er:YAG laser delivery. The fibers consist of a glass capillary tube and an inner coating of silver and polymer thin films that are deposited by use of a simple liquid-phase technique. The 250-mum-bore fiber exhibits a straight loss of 0.8 dB/m and a bending loss of 1.2 dB when it is bent 180 degrees at the output end, with a bending radius of 2 cm. The maximum energy delivered by the fibers is ~100 mJ.

  11. Equilibrium equations for nonlinear buckling analysis of drill-strings in 3D curved well-bores

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    With the development of drilling technology, the oil/gas well has evolved from its early vertical straight form to the inclined, horizontal, plane curved, or even 3D curved well-bore. Understanding of the buck- ling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation. Therefore, equilibrium equations for analyzing the buckling behavior of a drill-string in a 3D curved well-bore are required. Based on Love’s equilibrium equations for a curved and twisted rod in space, a set of equi- librium equations for the nonlinear buckling analysis of a drill-string in a 3D curved well-bore are de- rived by introducing a radial constraint of the well-bore. The proposed formulae can account for the well curvature and tortuosity. Thus, it can be used to analyze the buckling behaviors of a drill-string constrained in a well-bore and subjected to axial compression, torsion at its upper end, and gravity simultaneously. It is worth noting that the existing equations in the literature for a drill-string in a straight and plane curved well-bore with a constant curvature are a special case of the proposed model. Thus, the present model can provide a theoretical basis for the nonlinear buckling analysis of a drill-string constrained in a 3D curved well-bore.

  12. Equilibrium equations for nonlinear buckling analysis of drill-strings in 3D curved well-bores

    Institute of Scientific and Technical Information of China (English)

    TAN MeiLan; GAN LiFei

    2009-01-01

    With the development of drilling technology, the oil/gas well has evolved from its early vertical straight form to the inclined, horizontal, plane curved, or even 3D curved well-bore. Understanding of the buck-ling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation. Therefore, equilibrium equations for analyzing the buckling behavior of a drill-string in a 3D curved well-bore are required. Based on Love's equilibrium equations for a curved and twisted rod in space, s set of equi-librium equations for the nonlinear buckling analysis of a drill-string in a 3D curved well-bore are de-rived by introducing a radial constraint of the well-bore. The proposed formulae can account for the well curvature and tortuosity. Thus, it can be used to analyze the buckling behaviors of a drill-string constrained in a well-bore and subjected to axial compression, torsion at its upper end, and gravity simultaneously. It is worth noting that the existing equations in the literature for a drill-string in a straight and plane curved well-bore with a constant curvature are a special case of the proposed model. Thus, the present model can provide s theoretical basis for the nonlinear buckling analysis of a drill-string constrained in a 3D curved well-bore.

  13. A Size-Distance Scaling Demonstration Based on the Holway-Boring Experiment

    Science.gov (United States)

    Gallagher, Shawn P.; Hoefling, Crystal L.

    2013-01-01

    We explored size-distance scaling with a demonstration based on the classic Holway-Boring experiment. Undergraduate psychology majors estimated the sizes of two glowing paper circles under two conditions. In the first condition, the environment was dark and, with no depth cues available, participants ranked the circles according to their angular…

  14. Progress in the development of an 88-mm bore 10 Tn3Sn dipole magnet

    NARCIS (Netherlands)

    Ouden, den A.; Wessel, W.A.J.; Kirby, G.A.; Taylor, T.; Siegel, N.; Kate, ten H.H.J.

    2001-01-01

    A 10 T, 2-layer cos(&thetas;)-dipole model magnet with an 88 mm clear bore utilizing an advanced powder-in-tube Nb3Sn conductor is being developed for the LHC. A dedicated conductor development program has resulted in a well performing Rutherford cable containing strands that uniquely exhibit both a

  15. Distribution and biomass estimation of shell-boring algae in the intertidal area at Goa India

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Sharma, S.; Lande, V.

    The distribution and frequency of shell-boring green and blue-green algae in the intertidal at Goa, India were studied. The green alga Gomontia sp. and the blue green algae Hyella caespitosa Bornet et Flahault, H. gigas Lucas et Golubic...

  16. Technical Diagnostics of Tank Cannon Smooth Barrel Bore and Ramming Device

    Directory of Open Access Journals (Sweden)

    Jiri Balla

    2015-09-01

    Full Text Available The technical diagnostics of 125 mm tank cannon 2A46 smooth barrel and ramming devices are discussed respectively. Focuses on barrel diagnostics and suggests new procedures based on reconstructed BG20 Gun Barrel Bore Gauge System, measuring internal diameter of the barrel bore. The new system measures throughout the whole barrel bore the inner diameter not only at the beginning of barrel bore as it was usually measured before. Different nature of barrel wear was revealed between barrels firing sub-calibre and high explosive projectiles. A method for ramming device diagnostics is presented. An accurate method was proposed, determining projectile extraction force from barrel, as one of the main ramming device parameters for weapons that are used in all areas of armed forces. Results are based on experimental methods assessing the extraction forces from barrel after projectile loading. These tests were performed as a series of tests with consequent technical diagnostics according to the new Czech Defence Standards (derived from NATO standards. The results are presented as the new methodologies for diagnostics of 125 mm barrel 2A46 and ramming devices of tank T-72 for use by technical logistic units in the Czech Republic Armed Forces.

  17. EVALUATION OF RESERVOIR ROCK AND WELL BORE CEMENT ALTERATION WITH SUPERCRITICAL CO2

    Energy Technology Data Exchange (ETDEWEB)

    William k. O' Connor; Gilbert E Rush

    2009-01-01

    An evaluation of the alteration of reservoir rock and well bore cement at their interface, under supercritical CO{sub 2} (SCCO{sub 2}), was conducted at the laboratory-scale using simulated brine solutions at down-hole conditions. These studies were intended to identify potential leakage pathways for injected CO{sub 2} due to degradation of the well bore. Two distinct test series were conducted on core samples of the Mt. Simon sandstone from the Illinois Basin, IL, and the Grand Ronde basalt from the Pasco Basin, WA. LaFarge Class H well bore cement was used for both series. Reservoir rock/cement cores were immersed within a CO{sub 2}-saturated brine for up to 2000 hours at 35 degrees C and 100 atm CO{sub 2}. Results suggest that the impact of SCCO{sub 2} injection is reservoir-specific, being highly dependent on the reservoir brine and rock type. Brine pH can be significantly altered by CO{sub 2} injection, which in turn can dramatically impact the dissolution characteristics of the reservoir rock. Finally, well bore cement alteration was identified, particularly for fresh cast cement allowed to cure at SCCO{sub 2} conditions. However, this alteration was generally limited to an outer rind of carbonate and Ca-depleted cement which appeared to protect the majority of the cement core from further attack. These studies indicate that at the cement-rock interface, the annular space may be filled by carbonate which could act as an effective barrier against further CO{sub 2} migration along the well bore.

  18. Fundamental tests and operational suitability tests in the field. Large diameter boring with water jets (2nd report)

    Energy Technology Data Exchange (ETDEWEB)

    Oga, Kotaro; Higuchi, Kiyoshi; Uehara, Masabumi

    1987-09-25

    The application test of large diameter boring in coal seams assisted with water jet was made and two plunger pumps were used. Maximum hydraulic pressure were 300Kg/cm/sup 2/ and 700Kg/cm/sup 2/ and maximum flow rate were 140l/min and 47l/min respectively. Jet water was injected from each nozzle through the pressure resistant hose. Basic test and application test results in Taiheiyo and Akabira mines were summarized as follows: lengths of boreholes were 38 to 78 m and bored diameters were 30 to 70cm. The bored diameter depended on the coal zone hardness and the in-situ stress and indicated similar tendency to the previous large diameter boring. Boring speed was 0.14 to 0.33m/min in case of high velocity jet stream and 0.09m/min at the large diameter boring. Two miners can set and withdraw the boring equipments including the drilling work. (7 figs, 8 tabs, 6 refs)

  19. Reduction of claustrophobia with short-bore versus open magnetic resonance imaging: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Judith Enders

    Full Text Available BACKGROUND: Claustrophobia is a common problem precluding MR imaging. The purpose of the present study was to assess whether a short-bore or an open magnetic resonance (MR scanner is superior in alleviating claustrophobia. METHODS: Institutional review board approval and patient informed consent were obtained to compare short-bore versus open MR. From June 2008 to August 2009, 174 patients (139 women; mean age = 53.1 [SD 12.8] with an overall mean score of 2.4 (SD 0.7, range 0 to 4 on the Claustrophobia Questionnaire (CLQ and a clinical indication for imaging, were randomly assigned to receive evaluation by open or by short-bore MR. The primary outcomes were incomplete MR examinations due to a claustrophobic event. Follow-up was conducted 7 months after MR imaging. The primary analysis was performed according to the intention-to-treat strategy. RESULTS: With 33 claustrophobic events in the short-bore group (39% [95% confidence interval [CI] 28% to 50% versus 23 in the open scanner group (26% [95% CI 18% to 37%]; P = 0.08 the difference was not significant. Patients with an event were in the examination room for 3.8 min (SD 4.4 in the short-bore and for 8.5 min (SD 7 in the open group (P = 0.004. This was due to an earlier occurrence of events in the short-bore group. The CLQ suffocation subscale was significantly associated with the occurrence of claustrophobic events (P = 0.003. New findings that explained symptoms were found in 69% of MR examinations and led to changes in medical treatment in 47% and surgery in 10% of patients. After 7 months, perceived claustrophobia increased in 32% of patients with events versus in only 11% of patients without events (P = 0.004. CONCLUSIONS: Even recent MR cannot prevent claustrophobia suggesting that further developments to create a more patient-centered MR scanner environment are needed. TRIAL REGISTRATION: ClinicalTrials.gov NCT00715806.

  20. Functionally adapted final machining for cylinder bores made of cast iron; Funktionsgerechte Endbearbeitung von Zylinderbohrungen aus Gusseisen

    Energy Technology Data Exchange (ETDEWEB)

    Flores, G. [Gehring GmbH und Co. KG, Ostfildern (Germany); Fachhochschule Esslingen (Germany). Fachbereich Maschinenbau; Abeln, T.; Klink, U. [Gehring GmbH und Co. KG, Ostfildern (Germany)

    2007-03-15

    The cylinder bore is of interest for functional and production development processes. The cylinder bore of the piston stroke engine is the place of the highest friction efficiency and its topographical design is decisive for the oil consumption and the emission of modern motor-vehicles, a challenge for engine development and production engineers. Gehring GmbH and Co. KG, Ostfildern, Germany, is an experienced partner for the realization of efficient cylinder bores. On the basis of the tribological requirements present honing variants are described. (orig.)

  1. Application defects detection in the small bore pipe using infrared thermography technique

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Kyung Won; Kim, Dong Lyul; Jung, Hyun Chul; Hong, Dong Pyo; Kim, Kyeong Suk [Chosun Univ., Gwangju (Korea, Republic of)

    2013-02-15

    In the advanced research deducted infrared thermography (IRT) test using 4 inch pipe with artificial wall thinning defect to measure on the wall thinned nuclear pipe components. This study conducted for defect detection condition of nuclear small bore pipe research using deducted condition in the advanced research. Defect process is processed by change for defect length, circumferential direction angle, wall thinning depth. In the used equipment IR camera and two halogen lamps, whose full power capacity is 1 kW, halogen lamps and Target pipe experiment performed to the distance of the changed 1 m, 1.5 m, 2 m. To analysis of the experimental results ensure for the temperature distribution data, by this data measure for defect length. Artificial defect of 4 inch pipe is high reliability in the 2 m, but small bore pipe is in the 1.5 m from defect clearly was detected.

  2. Enhanced hole boring with two-color relativistic laser pulses in the fast ignition scheme

    Science.gov (United States)

    Yu, Changhai; Deng, Aihua; Tian, Ye; Li, Wentao; Wang, Wentao; Zhang, Zhijun; Qi, Rong; Wang, Cheng; Liu, Jiansheng

    2016-08-01

    A scheme of using two-color laser pulses for hole boring into overdense plasma as well as energy transfer into electron and ion beams has been studied using particle-in-cell simulations. Following an ultra-short ultra-intense hole-boring laser pulse with a short central wavelength in extreme ultra-violet range, the main infrared driving laser pulse can be guided in the hollow channel preformed by the former laser and propagate much deeper into an overdense plasma, as compared to the case using the infrared laser only. In addition to efficiently transferring the main driving laser energy into energetic electrons and ions generation deep inside the overdense plasma, the ion beam divergence can be greatly reduced. The results might be beneficial for the fast ignition concept of inertial confinement fusion.

  3. Experimental Study on Post Grouting Bearing Capacity of Large Diameter Bored Piles

    Directory of Open Access Journals (Sweden)

    Wang Duanduan

    2015-01-01

    Full Text Available Post grouting can improve the inherent defects such as the formation of the mud cake at pile side and the sediment at pile end in the process of bored pile construction. Thus post grouting has been widely used in Engineering. The purpose of this paper is to research the influences of post grouting to pile bearing capacity more systematically and intuitively. Combined with the static load test of four test piles in Weihe River Bridge test area of new airport highway in Xi’an, the bearing capacity and settlement of routine piles and post grouting piles are comparatively analyzed. The test results show that under the same geological condition, post grouting can improve the properties of pile tip and pile shaft soil of bored piles significantly, enhance the ultimate resistance, improve the ultimate bearing capacity and reduce the pile tip settlement. Then post grouting can aim to optimize pile foundation.

  4. The Effects of Guide Pads on Bore Diameter Enlargement Magnitude in Deep Hole Drilling

    OpenAIRE

    2016-01-01

    Deep hole machining accuracy plays a crucial role in product’s quality. The results of an investigation into the machining accuracy of deep drilling holes which highlights problems of bore diameter enlargement magnitude assessment are presented in this paper. Through the study of BTA deep drilling tool properties and mechanism, as well as the formation rule of deep hole surface, clarified the burnishing mechanism of guide pad in deep hole drilling, and obtained the directly relationship betwe...

  5. Boring sponges, an increasing threat for coral reefs affected by bleaching events.

    Science.gov (United States)

    Carballo, José L; Bautista, Eric; Nava, Héctor; Cruz-Barraza, José A; Chávez, Jesus A

    2013-04-01

    Coral bleaching is a stress response of corals induced by a variety of factors, but these events have become more frequent and intense in response to recent climate-change-related temperature anomalies. We tested the hypothesis that coral reefs affected by bleaching events are currently heavily infested by boring sponges, which are playing a significant role in the destruction of their physical structure. Seventeen reefs that cover the entire distributional range of corals along the Mexican Pacific coast were studied between 2005/2006, and later between 2009/2010. Most of these coral reefs were previously impacted by bleaching events, which resulted in coral mortalities. Sponge abundance and species richness was used as an indicator of bioerosion, and coral cover was used to describe the present condition of coral reefs. Coral reefs are currently highly invaded (46% of the samples examined) by a very high diversity of boring sponges (20 species); being the coral reef framework the substrate most invaded (56%) followed by the rubbles (45%), and the living colonies (36%). The results also indicated that boring sponges are promoting the dislodgment of live colonies and large fragments from the framework. In summary, the eastern coral reefs affected by bleaching phenomena, mainly provoked by El Niño, present a high diversity and abundance of boring sponges, which are weakening the union of the colony with the reef framework and promoting their dislodgment. These phenomena will probably become even more intense and severe, as temperatures are projected to continue to rise under the scenarios for future climate change, which could place many eastern coral reefs beyond their survival threshold.

  6. Submarine canyons as the preferred habitat for wood-boring species of Xylophaga (Mollusca, Bivalvia)

    Science.gov (United States)

    Romano, C.; Voight, J. R.; Company, J. B.; Plyuscheva, M.; Martin, D.

    2013-11-01

    Submarine canyons are often viewed as natural “debris concentrators” on the seafloor. Organic substrates may be more abundant inside than outside canyon walls. To determine the effects of the presence these substrates in the Blanes submarine canyon (NW Mediterranean) and its adjacent western open slope, we deployed wood to study colonizing organisms. Three replicate pine and oak cubes (i.e. most common trees inland) were moored at 900, 1200, 1500 and 1800 m depth and collected after 3, 9 and 12 months. Wood from inside the canyon was significantly more heavily colonized by the five morphotypes of wood-boring bivalves than was wood on the adjacent open slope. Xylophaga sp. A dominated all wood types and locations, with peak abundance at 900 and 1200 m depth. Its growth rate was highest (0.070 mm d-1) during the first three months and was faster (or it recruits earlier) in pine than in oak. Size distribution showed that several recruitment events may have occurred from summer to winter. Xylophaga sp. B, appeared first after 9 months and clearly preferred pine over oak. As the immersion time was the same, this strongly supported a specific association between recruiters and type of substrate. Three morphotypes, pooled as Xylophaga spp. C, were rare and seemed to colonize preferentially oak inside the canyon and pine in the adjacent open slope. Individuals of Xylophaga were more abundant inside the canyon than in nearby off-canyon locations. Blanes Canyon may serve as a long-term concentrator of land-derived vegetal fragments and as a consequence sustain more animals. Are the species richness and abundance of wood-boring bivalves higher inside the canyon than on the adjacent open slope? Do the composition and density of the wood-boring bivalves change with deployment time and depth, as well as on the type of the sunken wood? What is the growth rate of the dominant wood-boring species?

  7. The evolution of an internal bore at the Malin shelf break

    Directory of Open Access Journals (Sweden)

    J. Small

    Full Text Available Observations of internal waves were made at the Malin shelf edge during SESAME (Shelf Edge Studies Acoustic Measurement Experiment, a part of the NERC LOIS-SES experiment, in August-September 1996. These measurements provide a high resolution dataset demonstrating internal wave generation and propagation. This note presents observations of the evolution of an internal bore. The process is shown clearly in a sequence of thermistor chain tows across the shelf break covering a complete tidal cycle, as the double-sided bore transforms into a group of undulations and eventually into more distinct solitary waveforms. Current structures associated with the bore and waves were also observed by ship-mounted ADCP. Analysis of the waveforms in terms of the linear modes and empirical orthogonal functions (EOFs indicate the dominance of the first mode, which is typical of a shallow water seasonal thermocline environment. Determination of the phase speed of the waves from the consecutive ship surveys enabled the Doppler shift in the towed data to be removed, allowing analysis of the real length scales of the waves. The bore evolution has been modelled using a first order non-linear KdV model for the first mode, initialised with the waveform in the first survey. Comparison of the model and the observations show close agreement in the amplitudes, length scales, phase speeds and separations of the leading internal waves as they evolve. Finally, analysis of the observed internal wave shapes indicates that, within the uncertainties of measurement, the wave-lengths lie between those predicted by first and second order soliton theory.

    Key words. Oceanography: general (continental shelf processes; ocean prediction. Oceanography: physical (internal and inertial waves

  8. Study of spatio-temporal dynamics of laser-hole boring in near critical plasma

    Science.gov (United States)

    Tochitsky, Sergei; Gong, Chao; Fiuza, Frederico; Pigeon, Jeremy; Joshi, Chan

    2015-11-01

    At high-intensities of light, radiation pressure becomes one of the dominant mechanisms in laser-plasma interaction. The radiation pressure of an intense laser pulse can steepen and push the critical density region of an overdense plasma creating a cavity or a hole. This hole boring phenomenon is of importance in fast-ignition fusion, high-gradient laser-plasma ion acceleration, and formation of collisionless shocks. Here multi-frame picosecond optical interferometry is used for the first direct measurements of space and time dynamics of the density cavity as it is pushed forward by a train of CO2 laser pulses in a helium plasma. The measured values of the hole boring velocity into an overdense plasma as a function of laser intensity are consistent with a theory based on energy and momentum balance between the heated plasma and the laser and with two-dimensional numerical simulations. We show possibility to extract a relative plasma electron temperature within the laser pulse by applying an analytical theory to the measured hole boring velocities. This work was supported by DOE grant DE-SC0010064.

  9. Hole boring velocity measurements in near critical density plasmas by a CO2 laser pulse

    Science.gov (United States)

    Gong, Chao; Tochitsky, Sergei; Pigeon, Jeremy; Joshi, Chan

    2014-10-01

    Measurements of plasma dynamics during the interaction of a high-power laser pulse with an above critical density plasma is important for understanding absorption, transport and particle acceleration mechanisms. An important process that affects these mechanisms is hole boring occurring at the critical density because of the radiation pressure of the laser pulse. Yet, no systematic measurements of the hole boring velocity's (vhb) dependence on laser intensity (I) have been made. In this talk, we present experimental results of vhb in near critical density plasmas produced by CO2 laser as a function of I in the range of 1*1015 to 1.6*1016 W/cm2. A novel four frame Mach-Zehnder interferometer using a 1 ps, 532 nm probe laser pulse was developed to record the evolution of the plasma density profile and the motion of the near critical density layer. Using this diagnostic, we observed the motion of the steepened plasma profile due to the incident, time-structured CO2 laser pulse. Experimental results show the hole boring velocity increases from 0.004c to 0.007c as the laser intensity is increased from 1*1015 to 1.6*1016 W/cm2. This work is supported by DOE grant DE-FG02-92-ER40727, NSF grant PHY-0936266 at UCLA.

  10. Development of the large-bore powder gun for the Nevada Test Site

    Science.gov (United States)

    Esparza, James; Jensen, Brian

    2009-06-01

    Past fundamental work at the Nevada Test Site (NTS) U1a complex has been performed using explosively-driven flyer plates which provide high-pressure loading at the expense of some shock. In contrast, plate-impact experiments on single stage guns provide very planar loading conditions suitable for studying complex phenomena such as phase transitions and material strength, and provide important data useful for constraining and validating predictive models. The objective of the current work was to develop a large-bore powder gun capable of accelerating projectiles to moderately high velocity for impact experiments at NTS. This gun will span a performance gap between existing gun facilities and provide a means of examining phenomena over a wide range of stresses and time-scales. Advantages of the large-bore gun include the capability to load multiple samples simultaneously, the use of large diameter samples that significantly extend the time duration of the experiment, and minimal tilt. This new capability required the development of a disposable confinement system that used an explosively driven closure method to prevent contamination from moving up into the gun system. Experimental results of the qualification testing of the large-bore gun, the confinement system, and the explosively driven valve will be presented.

  11. Tri-bore PVDF hollow fibers with a super-hydrophobic coating for membrane distillation

    KAUST Repository

    Lu, Kang-Jia

    2016-04-26

    Membranes with good mechanical strength, high vapor flux and outstanding anti-wetting properties are essential for membrane distillation (MD) applications. In this work, porous polyvinylidene fluoride (PVDF) tri-bore hollow fiber membranes with super-hydrophobicity are developed to achieve these desired properties. The tri-bore hollow fiber offers better mechanical strength than the conventional single-bore fiber. To improve its anti-wetting properties, Teflon® AF 2400 is coated on the membrane surface. The effects of coating on membrane morphology, performance and anti-wetting properties have been thoroughly investigated. With an optimal coating condition (0.025 wt% of Teflon® AF 2400, 30 s), a super-hydrophobic surface with a contact angle of 151o is achieved. The resultant membrane shows an increase of 109% in liquid entry pressure (LEP) with a slight sacrifice of 21% in flux. Long term direct contact MD tests have confirmed that the Teflon® AF 2400 coated membrane has enhanced stability with an average flux of 21 kg m-2 h-1 and rejection of 99.99% at 60 °° C for desalination application.

  12. Magnetic design of large-bore superconducting quadrupoles for the AHF

    Energy Technology Data Exchange (ETDEWEB)

    Vladimir S Kashikhin et al.

    2002-08-13

    The Advanced Hydrotest Facility (AHF), under study by LANL, utilizes large-bore superconducting quadrupole magnets to image protons for radiography of fast events. In this concept, 50-GeV proton bunches pass through a thick object and are imaged by a lens system that analyzes the scattered beam to determine object details. Twelve simultaneous views of the object are obtained using multiple beam lines. The lens system uses two types of quadrupoles: a large bore (48-cm beam aperture) for wide field of view imaging and a smaller bore (23 cm aperture) for higher resolution images. The gradients of the magnets are 10.14 T/m and 18.58 T/m with magnetic lengths of 4.3 m and 3.0 m, respectively. The magnets are sufficiently novel to present a design challenge. Evaluation and comparisons were made for various types of magnet design: shell and racetrack coils, cold and warm iron, as well as an active superconducting screen. Nb{sub 3}Sn cable was also considered as an alternative to avoid quenching under high beam-scattering conditions. The superconducting shield concept eliminates the iron core and greatly lessens the cryogenic energy needed for cool down. Several options are discussed and comparisons are made.

  13. Assessment of water quality index of bore well water samples from some selected locations of South Gujarat, India.

    Science.gov (United States)

    Tripathi, S; Patel, H M; Srivastava, P K; Bafna, A M

    2013-10-01

    The present study calculates the water quality index (WQI) of some selected sites from South Gujarat (India) and assesses the impact of industries, agriculture and human activities. Chemical parameters were monitored for the calculation of WQI of some selected bore well samples. The results revealed that the WQI of the some bore well samples exceeded acceptable levels due to the dumping of wastes from municipal, industrial and domestic sources and agricultural runoff as well. Inverse Distance Weighting (IDW) was implemented for interpolation of each water quality parameter (pH, EC, alkalinity, total hardness, chloride, nitrate and sulphate) for the entire sampled area. The bore water is unsuitable for drinking and if the present state of affairs continues for long, it may soon become an ecologically dead bore.

  14. Small-bore chest tubes seem to perform better than larger tubes in treatment of spontaneous pneumothorax

    DEFF Research Database (Denmark)

    Iepsen, Ulrik Winning; Ringbæk, Thomas

    2013-01-01

    The aim of this study was to compare the efficacy and complications of surgical (large-bore) chest tube drainage with smaller and less invasive chest tubes in the treatment of non-traumatic pneumothorax (PT). ......The aim of this study was to compare the efficacy and complications of surgical (large-bore) chest tube drainage with smaller and less invasive chest tubes in the treatment of non-traumatic pneumothorax (PT). ...

  15. Estimation of Tsunami Bore Forces on a Coastal Bridge Using an Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Iman Mazinani

    2016-04-01

    Full Text Available This paper proposes a procedure to estimate tsunami wave forces on coastal bridges through a novel method based on Extreme Learning Machine (ELM and laboratory experiments. This research included three water depths, ten wave heights, and four bridge models with a variety of girders providing a total of 120 cases. The research was designed and adapted to estimate tsunami bore forces including horizontal force, vertical uplift and overturning moment on a coastal bridge. The experiments were carried out on 1:40 scaled concrete bridge models in a wave flume with dimensions of 24 m × 1.5 m × 2 m. Two six-axis load cells and four pressure sensors were installed to the base plate to measure forces. In the numerical procedure, estimation and prediction results of the ELM model were compared with Genetic Programming (GP and Artificial Neural Networks (ANNs models. The experimental results showed an improvement in predictive accuracy, and capability of generalization could be achieved by the ELM approach in comparison with GP and ANN. Moreover, results indicated that the ELM models developed could be used with confidence for further work on formulating novel model predictive strategy for tsunami bore forces on a coastal bridge. The experimental results indicated that the new algorithm could produce good generalization performance in most cases and could learn thousands of times faster than conventional popular learning algorithms. Therefore, it can be conclusively obtained that utilization of ELM is certainly developing as an alternative approach to estimate the tsunami bore forces on a coastal bridge.

  16. Zone electrophoresis in an inner-cooling wide-bore electrophoresis system with UV detection.

    Science.gov (United States)

    Guo, Yugao; Liu, Danning; Wang, Huaifeng; Yuan, Ruijuan; Bao, James Jianmin

    2008-08-01

    A novel, high-performance wide-bore electrophoresis (WE) system with inner-cooling has been developed. By introducing the mode of a shell and tube heat exchanger into this system to remove Joule heat generated during electrophoresis, it is feasible to extend electrophoresis from the conventional capillary (i.d. tube (i.d. >1000 microm). The wide tube allows the loading of over 1.0 microL of the sample with an LOD of 3.0 x 10(-4) mg/mL (signal-to-noise ratio, 3:1). Satisfactory separations of model compounds have been achieved on the WE system.

  17. RESEARCH ON THE DYNAMIC PROPERTY OF PIEZOELECTRIC MICRO DISPLACEMENT ACTUATOR FOR BORING ERROR COMPENSATION

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The dynamic property of piezoelectric micro displacement actuator (PMDA) is analyzed, especially the mechanical characteristic, lag phase property and hysteresis phenomenon. The influence factors of static and dynamic mechanical characteristics and the lag phase property are analyzed systematically. Three main influence factors of lag phase property are discovered. With comparison to mechanical Coulomb friction, a generalized model of nonlinear hysteresis of PMDA is advanced, based on the essential analysis of nonlinear phenomenon. Finally the application of PMDA in error compensation control system of boring is introduced. A good compensation result is achieved.

  18. MANTA, a novel plug-based vascular closure device for large bore arteriotomies: technical report.

    Science.gov (United States)

    van Gils, Lennart; Daemen, Joost; Walters, Greg; Sorzano, Todd; Grintz, Todd; Nardone, Sam; Lenzen, Mattie; De Jaegere, Peter P T; Roubin, Gary; Van Mieghem, Nicolas M

    2016-09-18

    Catheter-based interventions have become a less invasive alternative to conventional surgical techniques for a wide array of cardiovascular diseases but often create large arteriotomies. A completely percutaneous technique is attractive as it may reduce the overall complication rate and procedure time. Currently, large bore arteriotomy closure relies on suture-based techniques. Access-site complications are not uncommon and often seem related to closure device failure. The MANTA VCD is a novel collagen-based closure device that specifically targets arteriotomies between 10 and 22 Fr. This technical report discusses the MANTA design concept, practical instructions for use and preliminary clinical experience.

  19. Development of a Small-Bore, High-Efficiency, Helical Coil Electromagnetic Launcher

    Science.gov (United States)

    2003-06-01

    larger than a conventional railgun at 45 µH/m. The HCEL derives powered from a capacitor -based PFN which typically provides 11 kA current at a charge...gradient of the HCEL is more than a factor of 100 times larger than a conventional railgun at 45 mH/m. The HCEL derives powered from a capacitor -based...DEVELOPMENT OF A SMALL-BORE, HIGH-EFFICIENCY, HELICAL COIL ELECTROMAGNETIC LAUNCHER∗ T.G. Engelξ, W.C. Nunnally University of Missouri

  20. Measurements of an ion beam diameter extracted into air through a large-bore metal capillary

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Y.; Umigishi, M. [Graduate School of Humanities and Sciences, Nara Women’s University, Nara 630-8506 (Japan); Ishii, K.; Ogawa, H. [Department of Physics, Nara Women’s University, Nara 630-8506 (Japan)

    2015-07-01

    To extract an ion beam into air, the technique using a single macro-capillary has been paid attention. We have expanded the bore of the metal capillary up to 500 μm∅ inlet diameter to increase the beam intensity and have measured the intensity distributions of the extracted 3 MeV proton beam. Furthermore, we have tilted the capillary angle and measured the intensity distributions of the ion beam. In this article, we will present the experimental results together with the simulation which takes the tilt angles of the capillary into account.

  1. Measurement of in-bore side loads and comparison to first maximum yaw

    Institute of Scientific and Technical Information of China (English)

    Donald E. CARLUCCI; Ryan DECKER; Julio VEGA; Douglas RAY

    2016-01-01

    In-bore yaw of a projectile in a gun tube has been shown to result in range loss if the yaw is significant. An attempt was made to determine if relationships between in-bore yaw and projectile First Maximum Yaw (FMY) were observable. Experiments were conducted in which pressure transducers were mounted near the muzzle of a 155 mm cannon in three sets of four. Each set formed a cruciform pattern to obtain a differential pressure across the projectile. These data were then integrated to form a picture of what the overall pressure distribution was along the side of the projectile. The pressure distribution was used to determine a magnitude and direction of the overturning moment acting on the projectile. This moment and its resulting angular acceleration were then compared to the actual first maximum yaw observed in the test. The degree of correlation was examined using various statistical techniques. Overall uncertainty in the projectile dynamics was between 20%and 40%of the mean values of FMY.

  2. Bore holes and the vanishing of guinea worm disease in Ghana's upper region.

    Science.gov (United States)

    Hunter, J M

    1997-07-01

    Ghana's Upper Region provides an excellent example of the beneficial effects of improved water security provided by hand-pump tube wells. Following a Ghana-Canada bilateral development project that installed some 2500 pumps, protection rates against guinea worm disease may be estimated as 88% in the west, and 96% in the east. Survey comparisons between ca 1960 and 1990 show that dracunculiasis declined in 32 of a total of 38 areas. The shadow of guinea worm has been lifted from the land and, in many areas, a true "vanishing" has occurred. The few areas of disease increase are characterized by the lowest population densities, pioneer settlement for cotton farming, and an absence of bore holes. Vagaries of development have inadvertently produced disease transformations or "metamorphoses" from dracunculiasis to elephantiasis (lymphatic filariasis) in one area, and to red water disease (schistosomiasis hematobium) in other areas. Correlative associations between pump densities and guinea worm disease are weakened by the large size of areas for which disease is reported in 1990. One preliminary finding is that geographical distance to the pump is a stronger influence than demographic pressure on pumps, regarding dracunculiasis. Diminishing returns on higher pump densities in many areas support the idea of making fuller, safer use of supplementary non-pump water. Despite crises of fee payment and pump maintenance, the rural bore hole project has struck a mortal blow against guinea worm, and permanently raised the quality of life in the Upper Region.

  3. Developing of the large-bore powder gun for the Nevada test site

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Brian J [Los Alamos National Laboratory; Esparza, James S [Los Alamos National Laboratory

    2009-01-01

    Plate-impact experiments on single stage guns provide very planar loading conditions suitable for studying complex phenomena such as phase transitions and material strength, and provide important data useful for constraining and validating predictive models. The objective of the current work was to develop a large-bore (3.5-inches or greater) powder gun capable of accelerating projectiles to moderately high velocities (greater than 2.25 km/s) for impact experiments at Nevada Test Site. This gun will span a performance gap between existing gun facilities and provide a means of examining phenomena over a wide range of stresses and time-scales. Advantages of the large-bore gun include the capability to load multiple samples simultaneously, the use of large diameter samples that significantly extend the time duration of the experiment, and minimal tilt (no bow). This new capability required the development of a disposable confinement system that used an explosively driven closure method to prevent contamination from moving up into the gun system. Experimental results for both the gun system and the explosive valve are presented.

  4. Geotechnical maps for recommendation on bored pile capacity in Nakhon Ratchasima municipality, Thailand

    Directory of Open Access Journals (Sweden)

    Suksun Horpibulsuk

    2013-08-01

    Full Text Available This paper presents the development of geotechnical maps in Nakhon Ratchasima municipality, Nakhon Ratchasima province, Thailand based on the boring logs and in situ test results collected from public and private sector sources. The standard penetration number, N was used to identify the soil type. The soil deposits in Nakhon Ratchasima municipality are divided into three layers: medium-to-stiff silty clay with N 50. The medium-to-stiff silty clay layer has a thickness varying from 1.8 to 7.5 metres and an average N value of 14 with a relatively low standard deviation of 1.08. The first hard silty clay layer has a thickness varying from 1.2 to 3.0 metres and an average N value of 42 with a standard deviation of 1.37. For a practical application in foundation engineering in which the pile tips of the bored piles are located in the second hard stratum with N > 50, eight pile tip zones with approximated load capacity are recommended for pile lengths of 3-10 metres.

  5. Internal bores and gravity currents in a two-fluid system

    CERN Document Server

    Maruyama, Kiyoshi

    2014-01-01

    In this paper, a unified theory of internal bores and gravity currents is presented within the framework of the one-dimensional two-layer shallow-water equations. The equations represent four basic physical laws: the theory is developed on the basis of these laws. Though the first three of the four basic laws are apparent, the forth basic law has been uncertain. This paper shows first that this forth basic law can be deduced from the law which is called in this paper the conservation law of circulation. It is then demonstrated that, within the framework of the equations, an internal bore is represented by a shock satisfying the shock conditions that follow from the four basic laws. A gravity current can also be treated within the framework of the equations if the front conditions, i.e. the boundary conditions to be imposed at the front of the current, are known. Basically, the front conditions for a gravity current also follow from the four basic laws. When the gravity current is advancing along a no-slip bou...

  6. Asymmetric gradient coil design for use in a short, open bore magnetic resonance imaging scanner.

    Science.gov (United States)

    Wang, Yaohui; Liu, Feng; Li, Yu; Tang, Fangfang; Crozier, Stuart

    2016-08-01

    A conventional cylindrical whole-body MRI scanner has a long bore that may cause claustrophobia for some patients in addition to being inconvenient for healthcare workers accessing the patient. A short-bore scanner usually offers a small sized imaging area, which is impractical for imaging some body parts, such as the torso. This work proposes a novel asymmetric gradient coil design that offers a full-sized imaging area close to one end of the coil. In the new design, the primary and shielding coils are connected at one end whilst separated at the other, allowing the installation of the cooling system and shim trays. The proposed coils have a larger wire gap, higher efficiency, lower inductance, less resistance and a higher figure of merit than the non-connected coils. This half-connected coil structure not only improves the coils' electromagnetic performance, but also slightly attenuates acoustic radiation at most frequencies when compared to a non-connected gradient coil. It is also quieter in some frequency bands than a conventional symmetric gradient coil.

  7. Design of a Large Bore 60-T Pulse Magnet for Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    LESCH,B.; LI,L.; PERNAMBUCO-WISE,P.; ROVANG,DEAN C.; SCHNEIDER-MUNTAU,H.J.

    1999-09-23

    The design of a new pulsed magnet system for the generation of intense electron beams is presented. Determined by the required magnetic field profile along the axis, the magnet system consists of two coils (Coil No.1 and No.2) separated by a 32-mm axial gap. Each coil is energized independently. Both coils are internally reinforced with HIM Zylon fiber/epoxy composite. Coil No.1 made with AI-15 Glidcop wire has a bore of 110-mm diameter and is 200-mm long; it is energized by a 1.3-MJ, 13-kV capacitor bank. The magnetic field at the center of this coil is 30 T. Coil No.2 made with CuNb wire has a bore of 45 mm diameter, generates 60 T with a pulse duration of 60 ms, and is powered by a 4.0-MJ, 17.7-kV capacitor bank. We present design criteria, the coupling of the magnets, and the normal and the fault conditions during operation.

  8. Bore-Sight Calibration of Multiple Laser Range Finders for Kinematic 3D Laser Scanning Systems

    Directory of Open Access Journals (Sweden)

    Jaehoon Jung

    2015-05-01

    Full Text Available The Simultaneous Localization and Mapping (SLAM technique has been used for autonomous navigation of mobile systems; now, its applications have been extended to 3D data acquisition of indoor environments. In order to reconstruct 3D scenes of indoor space, the kinematic 3D laser scanning system, developed herein, carries three laser range finders (LRFs: one is mounted horizontally for system-position correction and the other two are mounted vertically to collect 3D point-cloud data of the surrounding environment along the system’s trajectory. However, the kinematic laser scanning results can be impaired by errors resulting from sensor misalignment. In the present study, the bore-sight calibration of multiple LRF sensors was performed using a specially designed double-deck calibration facility, which is composed of two half-circle-shaped aluminum frames. Moreover, in order to automatically achieve point-to-point correspondences between a scan point and the target center, a V-shaped target was designed as well. The bore-sight calibration parameters were estimated by a constrained least squares method, which iteratively minimizes the weighted sum of squares of residuals while constraining some highly-correlated parameters. The calibration performance was analyzed by means of a correlation matrix. After calibration, the visual inspection of mapped data and residual calculation confirmed the effectiveness of the proposed calibration approach.

  9. Measurement of in-bore side loads and comparison to first maximum yaw

    Directory of Open Access Journals (Sweden)

    Donald E. Carlucci

    2016-04-01

    Full Text Available In-bore yaw of a projectile in a gun tube has been shown to result in range loss if the yaw is significant. An attempt was made to determine if relationships between in-bore yaw and projectile First Maximum Yaw (FMY were observable. Experiments were conducted in which pressure transducers were mounted near the muzzle of a 155 mm cannon in three sets of four. Each set formed a cruciform pattern to obtain a differential pressure across the projectile. These data were then integrated to form a picture of what the overall pressure distribution was along the side of the projectile. The pressure distribution was used to determine a magnitude and direction of the overturning moment acting on the projectile. This moment and its resulting angular acceleration were then compared to the actual first maximum yaw observed in the test. The degree of correlation was examined using various statistical techniques. Overall uncertainty in the projectile dynamics was between 20% and 40% of the mean values of FMY.

  10. Analysis and separation of boron isotopes; Analyse et separation des isotopes du bore

    Energy Technology Data Exchange (ETDEWEB)

    Perie, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-11-01

    The nuclear applications of boron-10 justify the study of a method of measurement of its isotopic abundance as well as of very small traces of boron in different materials. A systematic study of thermionic emission of BO{sub 2}Na{sub 2}{sup +} has been carried out. In the presence of a slight excess of alkalis, the thermionic emission is considerably reduced. On the other hand, the addition of a mixture of sodium hydroxide-glycerol (or mannitol) to borax permits to obtain an intense and stable beam. These results have permitted to establish an operative method for the analysis of traces of boron by isotopic dilution. In other respects, the needs of boron-10 in nuclear industry Justify the study of procedures of separation of isotopes of boron. A considerable isotopic effect has been exhibited in the chemical exchange reaction between methyl borate and borate salt in solution. In the case of exchange between methyl borate and sodium borate, the elementary separation factor {alpha} is: {alpha}=(({sup 11}B/{sup 10}B)vap.)/(({sup 11}B/{sup 10}B)liq.)=1.03{sub 3}. The high value of this elementary effect has been multiplied in a distillation column in which the problem of regeneration of the reactive has been resolved. An alternative procedure replacing the alkali borate by a borate of volatile base, for example diethylamine, has also been studied ({alpha}=1,02{sub 5} in medium hydro-methanolic with 2,2 per cent water). (author) [French] Les applications nucleaires du bore 10 justifient l'etude d'une methode de mesure de son abondance isotopique dans divers materiaux ainsi que le dosage de tres faibles traces de bore. Une etude systematique de l'emission thermoionique de BO{sub 2} Na{sub 2}{sup +} a ete effectuee. En presence d'un leger exces d'alcalins, l'emission thermoionique est considerablement reduite. Par contre l'addition au borax d'un melange soude-glycerol (ou mannitol) permet d'obtenir un faisceau stable et intense

  11. STABILITY AND VIBRATION OF DRILL STRINGS WITH INTERNAL FLOWS OF LIQUIDS IN THE CHANNELS OF HORIZONTAL BORE-HOLES

    Directory of Open Access Journals (Sweden)

    Andrusenko E.N.

    2015-12-01

    Full Text Available In connection with elaboration of new technologies of hydrocarbons extraction from shales, in the oil and gas industry, the great attention is payed to the problems of drilling inclined and horizontal bore-holes. The peculiarities of these bore-hole drivage consist in essential influence of friction and contact forces on proceeding of drilling processes. In this paper, the problem about bifurcational buckling and small bending vibration of a rotating drill string lying in the channel of a horizontal bore-hole is stated. With allowance made for friction forces and additional constraint reactions, differential equations are deduced, their eigen-value solutions describing stability and vibration of the drill string of finite and infinite lengths are received.

  12. Phase contrast imaging of high-intensity laser hole boring of solid-density wires at LCLS-MEC

    Science.gov (United States)

    Schumaker, W.; Brown, S.; Curry, C.; Gauthier, M.; Gamboa, E.; Goede, S.; Fletcher, L.; Kim, J.; MacDonald, M.; Mishra, R.; Roedel, C.; Glenzer, S.; Fiuza, F.; Granados, E.; Nagler, B.; Zhou, Z.; MacKinnon, A.; Obst, L.; Ziel, K.; Pak, A.; Williams, G.; Fajardo, M.

    2016-10-01

    High-intensity, relativistic (a0 > 1) laser plasma interactions on solid surfaces produce a rich mix of dynamics on the laser timescale (Weibel instabilities, surface effects, sheath formation, etc.) and hydrodynamic timescale (hole-boring, shocks, etc.). Probing these interactions optically is difficult due to critical density layer obscuring the surface of the target, whereas probing with hard X-rays from K-alpha sources does not sufficiently resolve these interactions temporally as they are typically many ps in duration. Presented here are the first experimental measurements of laser hole-boring on a carbon wire surfaces performed at the LCLS-MEC facility. With laser intensities of up to 1019 W / cm2 , we observe the dissociation of micron-sized wires over 100 ps timescale with peak hole boring velocities up to 0.001 c using phase-contrast imaging. This work was funded by DOE FES under FWP #100182.

  13. Etudes sur la phase carbure de bore. Corrélations propriétés-composition

    OpenAIRE

    1982-01-01

    No english abstract; La connaissance du diagramme de phases bore-carbone, des propriétés physico chimiques et la structure du carbure de bore ont été approfondies. Dans ce but, nous avons mis en œuvre principalement deux méthodes de préparation de nos échantillons : ¤ la fusion au canon à électrons, ¤ la compression à chaud. Il faut noter que nous avons considérablement amélioré cette dernière méthode pour la rendre apte à la préparation en particulier d'échantillons constitués de bore pur ou...

  14. Maintaining Masculinity in Mid-Twentieth-Century American Psychology: Edwin Boring, Scientific Eminence, and the "Woman Problem".

    Science.gov (United States)

    Rutherford, Alexandra

    2015-01-01

    Using mid-twentieth-century American psychology as my focus, I explore how scientific psychology was constructed as a distinctly masculine enterprise and was navigated by those who did not conform easily to this masculine ideal. I show how women emerged as problems for science through the vigorous gatekeeping activities and personal and professional writings of disciplinary figurehead Edwin G. Boring. I trace Boring's intellectual and professional socialization into masculine science and his efforts to understand women's apparent lack of scientific eminence, efforts that were clearly undergirded by preexisting and widely shared assumptions about men's and women's capacities and preferences.

  15. Reducing ion energy spread in hole-boring radiation pressure acceleration by using two-ion-species targets

    CERN Document Server

    Weng, S M; Sheng, Z M

    2014-01-01

    The generation of fast ion beams in the hole-boring radiation pressure acceleration by intense laser pulses has been studied for targets with different ion components. We find that the oscillation of the longitudinal electric field for accelerating ions can be effectively suppressed by using a two-ion-species target, because fast ions from a two-ion-species target are distributed into more bunches and each bunch bears less charge. Consequently, the energy spread of ion beams generated in the hole-boring radiation pressure acceleration can be greatly reduced down to 3.7% according to our numerical simulation.

  16. Active and passive migration in boring isopods Limnoria spp. (Crustacea, Peracarida) from kelp holdfasts

    Science.gov (United States)

    Miranda, Leonardo; Thiel, Martin

    2008-10-01

    Many boring isopods inhabit positively buoyant substrata (wood and algae), which float after detachment, permitting passive migration of inhabitants. Based on observations from previous studies, it was hypothesized that juvenile, subadult and male isopods migrate actively, and will rapidly abandon substrata after detachment. In contrast, reproductive females and small offspring were predicted to remain in floating substrata and thus have a high probability to disperse passively via rafting. In order to test this hypothesis, a colonization and an emigration experiment were conducted with giant kelp ( Macrocystis integrifolia), the holdfasts of which are inhabited by boring isopods from the genus Limnoria. A survey of benthic substrata in the kelp forest confirmed that limnoriids inhabited the holdfasts and did not occur in holdfast-free samples. Results of the colonization experiment showed that all life history stages of the boring isopods immigrated into young, largely uncolonized holdfasts, and after 16 weeks all holdfasts were densely colonized. In the emigration experiment, all life history stages of the isopods rapidly abandoned the detached holdfasts — already 5 min after detachment only few individuals remained in the floating holdfasts. After this initial rapid emigration of isopods, little changes in isopod abundance occurred during the following 24 h, and at the end of the experiment some individuals of all life history stages still remained in the holdfasts. These results indicate that all life history stages of Limnoria participate in both active migration and passive dispersal. It is discussed that storm-related dynamics within kelp forests may contribute to intense mixing of local populations of these burrow-dwelling isopods, and that most immigrants to young holdfasts probably are individuals emigrating from old holdfasts detached during storm events. The fact that some individuals of all life history stages and both sexes remain in floating

  17. Cylindricity Error Measuring and Evaluating for Engine Cylinder Bore in Manufacturing Procedure

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2016-01-01

    Full Text Available On-line measuring device of cylindricity error is designed based on two-point method error separation technique (EST, which can separate spindle rotation error from measuring error. According to the principle of measuring device, the mathematical model of the minimum zone method for cylindricity error evaluating is established. Optimized parameters of objective function decrease to four from six by assuming that c is equal to zero and h is equal to one. Initial values of optimized parameters are obtained from least square method and final values are acquired by the genetic algorithm. The ideal axis of cylinder is fitted in MATLAB. Compared to the error results of the least square method, the minimum circumscribed cylinder method, and the maximum inscribed cylinder method, the error result of the minimum zone method conforms to the theory of error evaluation. The results indicate that the method can meet the requirement of engine cylinder bore cylindricity error measuring and evaluating.

  18. Prediction of Surface Roughness Based on Machining Condition and Tool Condition in Boring EN31 Steel

    Directory of Open Access Journals (Sweden)

    P. Mohanaraman

    2016-04-01

    Full Text Available Prediction of Surface roughness plays a vital role in manufacturing process. In manufacturing industries, productions of metallic materials require high surface finish in various components. In the present work, the effect of spindle speed, feed rate, depth of cut and flank wear of the tool on the surface roughness has been studied. Carbide tipped insert was used for boring operation. Experiments were conducted in CNC lathe. The experimental setup was prepared with sixteen levels of cutting parameters and was conducted with two tool tip conditions in dry machining. A piezoelectric accelerometer was used to measure the vibrational signals while machining. The data acquisition card which connected between accelerometer and lab-view software to record the signals. Simple linear and least median regression models were used for prediction of surface roughness. The models were developed by weka analysis software. The best suitable regression model is implemented based on maximum correlation coefficient and the minimum error values.

  19. Ecology of the Wood-boring Bivalve Martesia striata (Pholadidae) in Indian Waters

    Science.gov (United States)

    Yennawar, P. L.; Thakur, N. L.; Anil, A. C.; Venkat, K.; Wagh, A. B.

    1999-08-01

    Martesia striata (Linnaeus) is one of the dominant wood-boring organisms found in Indian waters. Incidence of this organism in the Zuari estuary (Goa) was evaluated by exposing wooden panels (Mangifera indica) to the marine environment between January 1996 and January 1997. Effects of salinity variation on embryonic and larval development were evaluated (salinity 0, 10, 20, 30, 35, 40 and 50, temperature 25 °C) and maximum metamorphic success was observed at 30 salinity. Results of the rearing experiments, destruction pattern of wood in the environment and reproductive biology indicate that although recruitment is halted during the monsoon, adults survive and become reproductively mature in the following post-monsoon, leading to increased recruitment during pre-monsoon months.

  20. Predator-prey interactions between shell-boring beetle larvae and rock-dwelling land snails.

    Science.gov (United States)

    Baalbergen, Els; Helwerda, Renate; Schelfhorst, Rense; Castillo Cajas, Ruth F; van Moorsel, Coline H M; Kundrata, Robin; Welter-Schultes, Francisco W; Giokas, Sinos; Schilthuizen, Menno

    2014-01-01

    Drilus beetle larvae (Coleoptera: Elateridae) are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae) species in Greece. We observe that Drilus species may be facultative or obligate Albinaria-specialists. We map geographically varying predation rates in Crete, where on average 24% of empty shells carry fatal Drilus bore holes. We also provide first-hand observations and video-footage of prey entry and exit strategies of the Drilus larvae, and evaluate the potential mutual evolutionary impacts. We find limited evidence for an effect of shell features and snail behavioral traits on inter- and intra-specifically differing predation rates. We also find that Drilus predators adjust their predation behavior based on specific shell traits of the prey. In conclusion, we suggest that, with these baseline data, this interesting predator-prey system will be available for further, detailed more evolutionary ecology studies.

  1. Dosimetric impact of image artifact from a wide-bore CT scanner in radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Vincent; Podgorsak, Matthew B.; Tran, Tuan-Anh; Malhotra, Harish K.; Wang, Iris Z. [Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States)

    2011-07-15

    Purpose: Traditional computed tomography (CT) units provide a maximum scan field-of-view (sFOV) diameter of 50 cm and a limited bore size, which cannot accommodate a large patient habitus or an extended simulation setup in radiation therapy (RT). Wide-bore CT scanners with increased bore size were developed to address these needs. Some scanners have the capacity to reconstruct the CT images at an extended FOV (eFOV), through data interpolation or extrapolation, using projection data acquired with a conventional sFOV. Objects that extend past the sFOV for eFOV reconstruction may generate image artifacts resulting from truncated projection data; this may distort CT numbers and structure contours in the region beyond the sFOV. The purpose of this study was to evaluate the dosimetric impact of image artifacts from eFOV reconstruction with a wide-bore CT scanner in radiotherapy (RT) treatment planning. Methods: Testing phantoms (i.e., a mini CT phantom with equivalent tissue inserts, a set of CT normal phantoms and anthropomorphic phantoms of the thorax and the pelvis) were used to evaluate eFOV artifacts. Reference baseline images of these phantoms were acquired with the phantom centrally positioned within the sFOV. For comparison, the phantoms were then shifted laterally and scanned partially outside the sFOV, but still within the eFOV. Treatment plans were generated for the thoracic and pelvic anthropomorphic phantoms utilizing the Eclipse treatment planning system (TPS) to study the potential effects of eFOV artifacts on dose calculations. All dose calculations of baseline and test treatment plans were carried out using the same MU. Results: Results show that both body contour and CT numbers are altered by image artifacts in eFOV reconstruction. CT number distortions of up to -356 HU for bone tissue and up to 323 HU for lung tissue were observed in the mini CT phantom. Results from the large body normal phantom, which is close to a clinical patient size, show

  2. Dynamic nuclear polarization for magnetic resonance imaging. An in-bore approach

    Energy Technology Data Exchange (ETDEWEB)

    Krummenacker, Jan G.

    2012-07-01

    In this thesis, the development of an in-bore liquid state DNP polarizer for MRI applications operating in flow through mode at a magnetic field strength of 1.5 T was described. After an introductory chapter 1 and a chapter 2 on the theoretical background, chapter 3 dealt chiefly with the challenge of performing liquid state DNP at a high magnetic field of 9.2 T. The feasibility of performing liquid state DNP at this field was demonstrated for various solvents, as well as for metabolites in solution. Chapter 4 then moved to the aim of this work, the application of liquid state DNP for MRI experiments. It introduced the rationale of our approach, the hardware that was developed and demonstrated its performance in a clinical MRI tomograph.

  3. Lesson for the Calculation No Longer Boring%让计算课不再枯燥

    Institute of Scientific and Technical Information of China (English)

    冯培崇

    2014-01-01

    Although calculation content is boring,but if we can stand on the perspective of the students to look at teaching,carefully adjust their own class,in calculation classes focus on creating close to the situation of life to arouse students’interests,pay attention to let students understand calculate.%计算内容虽然是枯燥的,但教师要能站在学生的角度去审视教学,精心调整自己的课堂,在计算课中注重创设贴近生活的情境以调动学生的兴趣,注重让学生明白算理。

  4. Measurements of laser-hole boring into overdense plasmas using x-ray laser refractometry (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Kodama, R.; Takahashi, K.; Tanaka, K.A.; Kato, Y. [Institute of Laser Engineering (ILE), Osaka University, Suita, Osaka 565 (Japan); Murai, K. [DMP, ONRI, Ikeda, Osaka 563 (Japan); Weber, F.; Barbee, T.W.; DaSilva, L.B. [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)

    1999-01-01

    We developed a 19.6 nm laser x-ray laser grid-image refractometer (XRL-GIR) to diagnose laser-hole boring into overdense plasmas. The XRL-GIR was optimized to measure two-dimensional electron density perturbation on a scale of a few tens of {mu}m in underdense plasmas. Electron density profiles of laser-produced plasmas were obtained for 10{sup 20}{endash}10{sup 22}thinspcm{sup {minus}3} with the XRL-GIR and for 10{sup 19}{endash}10{sup 20}thinspcm{sup {minus}3} from an ultraviolet interferometer, the profiles of which were compared with those from hydrodynamic simulation. By using this XRL-GIR, we directly observed laser channeling into overdense plasmas accompanied by a bow shock wave showing a Mach cone ascribed to supersonic propagation of the channel front. {copyright} {ital 1999 American Institute of Physics.}

  5. 3D Finite Element Simulation of Tunnel Boring Machine Construction Processes in Deep Water Conveyance Tunnel

    Institute of Scientific and Technical Information of China (English)

    ZHONG Denghua; TONG Dawei

    2009-01-01

    Applying stiffness migration method, a 3D finite element mechanical model is established to simulate the excavation and advance processes. By using 3D nonlinear finite element method, the tunnel boring machine (TBM) excavation process is dynamically simulated to analyze the stress and strain field status of surrounding rock and segment. The maximum tensile stress of segment ring caused by tunnel construction mainly lies in arch bottom and presents zonal distribution. The stress increases slightly and limitedly in the course of excavation. The maxi-mum and minimum displacements of segment, manifesting as zonal distribution, distribute in arch bottom and vault respectively. The displacements slightly increase with the advance of TBM and gradually tend to stability.

  6. Numerical Simulation of Muzzle Flow Field Based on Calculation of Combustion Productions in Bore

    Institute of Scientific and Technical Information of China (English)

    Liang Wang∗,Houqian Xu,Wei Wu; Rui Xue

    2015-01-01

    To improve the accuracy of numerical simulation of muzzle chemical flow field, and study the gunpowder combustion productions, the muzzle flow field is simulated coupled with the calculation of combustion productions in bore. The calculation in bore uses the gibbs free⁃energy minimization method and the classical interior ballistics model. The simulation of the muzzle flow field employs the multi⁃component ALE ( Arbitrary Lagrange⁃Euler ) equations. Computations are performed for a 12�7 mm gun. From 2�48 ms to 3�14 ms, the projectile moves in the gun barrel. CO and H2 O masses decrease by 3�37% and 6�51%, and H2 and CO2 masses increase by 11�11% and 10�58%. The changes conform to the fact that the water⁃gas equilibrium reaction of all reactions plays a dominant role in this phase. After the projectile leaves the barrel, the masses of H2 and CO decrease, and the masses of H2 O and CO2 increase. When it moves to 80d away from the muzzle, the decreases are 12�75% and 8�05%, and the increases are 12�76% and 36�26%, which tallies with the existence of muzzle flame. Further, CO and H2 burn more and more fiercely with the muzzle pressure pg increasing, and burn more and more weakly with the altitude rising. When two projectiles launch in series, the combustion of the second projectile muzzle flow field is fiercer than the first projectile. Analysis results have shown that the proposed method is effective for simulating the muzzle flow filed.

  7. CFD Modelling of Bore Erosion in Two-Stage Light Gas Guns

    Science.gov (United States)

    Bogdanoff, D. W.

    1998-01-01

    A well-validated quasi-one-dimensional computational fluid dynamics (CFD) code for the analysis of the internal ballistics of two-stage light gas guns is modified to explicitly calculate the ablation of steel from the gun bore and the incorporation of the ablated wall material into the hydrogen working cas. The modified code is used to model 45 shots made with the NASA Ames 0.5 inch light gas gun over an extremely wide variety of gun operating conditions. Good agreement is found between the experimental and theoretical piston velocities (maximum errors of +/-2% to +/-6%) and maximum powder pressures (maximum errors of +/-10% with good igniters). Overall, the agreement between the experimental and numerically calculated gun erosion values (within a factor of 2) was judged to be reasonably good, considering the complexity of the processes modelled. Experimental muzzle velocities agree very well (maximum errors of 0.5-0.7 km/sec) with theoretical muzzle velocities calculated with loading of the hydrogen gas with the ablated barrel wall material. Comparison of results for pump tube volumes of 100%, 60% and 40% of an initial benchmark value show that, at the higher muzzle velocities, operation at 40% pump tube volume produces much lower hydrogen loading and gun erosion and substantially lower maximum pressures in the gun. Large muzzle velocity gains (2.4-5.4 km/sec) are predicted upon driving the gun harder (that is, upon using, higher powder loads and/or lower hydrogen fill pressures) when hydrogen loading is neglected; much smaller muzzle velocity gains (1.1-2.2 km/sec) are predicted when hydrogen loading is taken into account. These smaller predicted velocity gains agree well with those achieved in practice. CFD snapshots of the hydrogen mass fraction, density and pressure of the in-bore medium are presented for a very erosive shot.

  8. Load-sharing characteristic of multiple pinions driving in tunneling boring machine

    Science.gov (United States)

    Wei, Jing; Sun, Qinchao; Sun, Wei; Ding, Xin; Tu, Wenping; Wang, Qingguo

    2013-05-01

    The failure of the key parts, such as gears, in cutter head driving system of tunneling boring machine has not been properly solved under the interaction of driving motors asynchronously and wave tunneling torque load. A dynamic model of multi-gear driving system is established considering the inertia effects of driving mechanism and cutter head as well as the bending-torsional coupling. By taking into account the nonlinear coupling factors between ring gear and multiple pinions, the influence for meshing angle by bending-torsional coupling and the dynamic load-sharing characteristic of multiple pinions driving are analyzed. Load-sharing coefficients at different rotating cutter head speeds and input torques are presented. Numerical results indicate that the load-sharing coefficients can reach up to 1.2-1.3. A simulated experimental platform of the multiple pinions driving is carried out and the torque distributions under the step load in driving shaft of pinions are measured. The imbalance of torque distribution of pinions is verified and the load-sharing coefficients in each pinion can reach 1.262. The results of simulation and test are similar, which shows the correctness of theoretical model. A loop coupling control method is put forward based on current torque master slave control method. The imbalance of the multiple pinions driving in cutter head driving system of tunneling boring machine can be greatly decreased and the load-sharing coefficients can be reduced to 1.051 by using the loop coupling control method. The proposed research provides an effective solution to the imbalance of torque distribution and synchronous control method for multiple pinions driving of TBM.

  9. Study on the response of the full-bore conductance sensor for water cut measurement

    Science.gov (United States)

    Xie, Ronghua; Liu, Xingbin; Hu, Jinhai; Dai, Xuefei; Shan, Fujun; Xu, Wenfeng

    2009-02-01

    This paper has proposed a new structure of full-bore conductance sensor, which is designed for measuring water cut of the oil-water two-phase flow. The structure of the full-bore conductance sensor and the measurement principle are introduced in the paper. The mental ring-shaped electrode is mounted on the outside wall of the cylindrical insulation body. When the electrode is provided with constant current, according to the electrical theory, the electrode generates a voltage, the value of which is inversely proportional to the conductivity of fluid flowing between the sensor and the casing. The electrostatic field simulations of the sensor are accomplished by using ANSYS software. The results of the potential distribution simulation show that the potential decays quickly from the electrode along r direction (radial) and z direction (axial)to both sides, and the potential only distributes in a very narrow area near the electrode. A series of static experiments on the sensor are carried out in laboratory. The experiment results agree with the simulation results. In radial direction, the closer the rod is to the sensor, the more sensitive the sensor becomes and the greater the relative response becomes. In axial direction, the electrode only responds in a certain region on both sides of the electrode and decays rapidly from the electrode to both sides. And the salinity experiment is conducted in salt solution (3000 ppm), which shows that within the allowable range of experiment error, there is no effect of salinity on the sensor response. response.

  10. Bored pile construction%冲孔灌注桩施工要点

    Institute of Scientific and Technical Information of China (English)

    陈明晓; 洪小灵

    2012-01-01

    Bored pile foundation as a mature technology,because of its simple installation,construction machinery import and the convenience,fast pile forming speed,quality and reliable,widely used.The bored pile construction process may produce problems in detail,for coastal mud layer too thick,too many boulder distribution of geological environment,the old city construction site is small,it may encounter problems,especially the pile press machine,the punching process emerged in the mud circulation plugging,probe stone underwater concrete,quality control,reasonable solutions and preventive measures.%冲孔灌注桩作为一种成熟的桩基工艺,因其施工机械安装简单、进出场地方便,成桩速度快、桩身质量可靠,得到广泛的应用。本文对冲孔灌注桩施工过程中可能产生的问题进行详细阐述,针对沿海淤泥层过厚,孤石分布偏多的地质环境,老城区施工场地偏小,就可能遇到的问题,特别是桩机走机、冲孔过程中出现的泥浆循环堵管、探头石、水下混凝土质量控制,提出合理的解决方法及预防措施。

  11. Influence of friction on buckling of a drill string in the circular channel of a bore hole

    Directory of Open Access Journals (Sweden)

    Valery Gulyayev

    2016-10-01

    Full Text Available Abstract Enhancement of technology and techniques for drilling deep directed oil and gas bore hole is one of the most important problems of the current petroleum industry. Not infrequently, the drilling of these bore holes is attended by occurrence of extraordinary situations associated with technical accidents. Among these is the Eulerian loss of stability of a drill string in the channel of a curvilinear bore hole. Methods of computer simulation should play a dominant role in prediction of these states. In this paper, a new statement of the problem of critical buckling of the drill strings in 3D curvilinear bore holes is proposed. It is based on combined use of the theory of curvilinear elastic rods, Eulerian theory of stability, theory of channel surfaces, and methods of classical mechanics of systems with nonlinear constraints. It is noted that the stated problem is singularly perturbed and its solutions have the shapes of localized harmonic wavelets. The calculation results showed that the friction effects lead to essential redistribution of internal axial forces, as well as changing the eigenmode shapes and sites of their localization. These features make the buckling phenomena less predictable and raise the role of computer simulation of these effects.

  12. Triple-bore hollow fiber membrane contactor for liquid desiccant based air dehumidification

    KAUST Repository

    Bettahalli, N.M. Srivatsa

    2016-04-26

    Dehumidification is responsible for a large part of the energy consumption in cooling systems in high humidity environments worldwide. Improving efficiency is therefore essential. Liquid desiccants offer a promising solution for dehumidification, as desired levels of humidity removal could be easily regulated. The use of membrane contactors in combination with liquid desiccant is attractive for dehumidification because they prevent direct contact between the humid air and the desiccant, removing both the potential for desiccant carryover to the air and the potential for contamination of the liquid desiccant by dust and other airborne materials, as well as minimizing corrosion. However, the expected additional mass transport barrier of the membrane surface can lower the expected desiccation rate per unit of desiccant surface area. In this context, hollow fiber membranes present an attractive option for membrane liquid desiccant contactors because of their high surface area per unit volume. We demonstrate in this work the performance of polyvinylidene fluoride (PVDF) based triple-bore hollow fiber membranes as liquid desiccant contactors, which are permeable to water vapor but impermeable to liquid water, for dehumidification of hot and humid air.

  13. Preliminary studies of a novel multifunctional wide-bore electrophoresis system.

    Science.gov (United States)

    Li, You-Xin; Dan, Yong-Bo; Fang, Xin; Bao, James Jianmin

    2010-10-01

    This paper presents the results obtained from a novel multifunctional analysis platform established on the basis of wide-bore electrophoresis (WBE) and CE. The WBE–CE system integrated various analytical steps including separation, transfer, reaction, detection, and storage into a single system. During the WBE–CE process, a distinct three-electrode format was adopted to continuously separate and transfer samples between WBE and CE without the interruption of switching on-and-off the power suppliers. This continuous mode of operation also helped to eliminate the need for exactly timing the transfer of specific samples zone from WBE to CE and avoided the danger of missing specific samples. Samples representing mixtures of acids, bases, or proteins were analyzed on this system for evaluating its feasibility and applicability. The results indicated that the resolution achieved on this WBE–CE system was better than either the WBE or the CE alone. Further, samples transferred out of the WBE system could participate in online reaction, such as enzymatic reaction in the CE. Alternatively, samples from the WBE system could be transferred out and stored offline in a vial for post-transfer reaction. The results demonstrated that this WBE–CE system has the potential to be a multifunctional platform for a range of applications.

  14. Flexible but boring: medical students' perceptions of a career in general practice.

    Science.gov (United States)

    Koehler, Nicole; McMenamin, Christine

    2016-07-01

    Australia will continue to face a general practitioner (GP) shortage unless a significant number of medical students make general practice their chosen career. Perceptions regarding general practice may influence career choices. Thus this study investigated what Australian medical students perceived to be the advantages and disadvantages of pursuing a career in general practice via an anonymous online survey. Fifty-one students indicated general practice to be their first ranked career preference, 200 indicated a career other than general practice, and 106 were undecided. Two-hundred and two students reported having been on a GP placement, whereas 88 students had not. Flexibility, continuity of patient care and work-life balance were the three most common stated advantages to pursuing a career in general practice whereas general practice being boring, poorly paid, and of low prestige were the three most common disadvantages stated. Some disadvantages stated by those with a non-GP preference were not stated by those with a GP preference (e.g. lack of procedural skills, lack of career advancement opportunities). Students with more than 80 h of GP placement experience were more likely to list the advantages of work-life balance and a diversity of problems/illnesses/patients than those with no placement experience but were also more likely to list the disadvantage of low prestige. Negative stereotypes regarding general practice continue to exist which may influence students' career choices.

  15. Safety assessment of a bored pile diaphragm in a medium-height dam

    Directory of Open Access Journals (Sweden)

    Sainov Mikhail Petrovich

    2014-01-01

    Full Text Available The article deals with the analysis of embankment dams of a new type: a rockfill dam with a clay-cement concrete diaphragm built by bored-pile method. The authors give the results of numerical modeling of a stress-strain state of 69 m high dam, where a diaphragm in the form of a slurry trench cutoff wall cuts the whole dam body and a23 m deep gravel-pebble foundation. The co-authors describe a dam design where the diaphragm is constructed in three lifts. The diaphragm lifts are connected by slabs made of clay-cement concrete or clay. Numerical modeling was carried out with the use of the author’s computer program with consideration of non-linearity of soils deformation. Analyses showed that clay-cement concrete of a slurry trench cutoff wall is in a favorable stress state, as clay-cement concrete by its deformation characteristics (E = 100 МPа is close to gravel-pebble soil. The diaphragm deflections turned to be small; therefore, tensile stresses will not occur in it. In the diaphragm the clay-cement concrete is in a state of triaxial compression, therefore, its strength will be higher than unconfined compression strength (1-2 МPа. It may be expected that its strength will be provided. The nodes of connection of the slurry trench cutoff wall lifts also demonstrate safe operation.

  16. Arrival of the Robbins machine in LSS1 after completing the boring of the SPS tunnel.

    CERN Multimedia

    1974-01-01

    A few months after the signature of the agreement giving the go-ahead for the expansion of CERN into French territory (see Bulletin no.24/2004), work began on the Super Proton Synchrotron (SPS). Two years later, on 31 July 1974, the Robbins tunnel-boring machine excavating the SPS tunnel returned to its starting point (see photograph). It had excavated a tunnel with a circumference of 7 kilometres, at an average depth of 40 metres below the surface. The tunnel straddled the Franco-Swiss border, making the SPS the first cross-border accelerator. More than a thousand magnets were needed to equip the ring. The civil engineering and installation work was completed in record time after only four years. The SPS was equipped with a control system which was ahead of its time, consisting of 24 small control computers distributed in the tunnel and the control room and communicating by means of a high-rate data transmission system. The main control room housed only four consoles as opposed to the banks of electronic eq...

  17. Initial studies of Bremsstrahlung energy deposition in small-bore superconducting undulator structures in linac environments

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, T.; Tatchyn, R. [Stanford Univ., CA (United States)

    1995-12-31

    One of the more promising technologies for developing minimal-length insertion devices for linac-driven, single-pass Free Electron Lasers (FELs) operating in the x-ray range is based on the use of superconducting (SC) materials. In recent FEL simulations, for example, a bifilar helical SC device with a 2 cm period and 1.8 T field was found to require a 30 m saturation length for operation at 1.5{Angstrom} on a 15 GeV linac, more than 40% shorter than an alternative hybrid/permanent magnet (hybrid/PM) undulator. AT the same time, however, SC technology is known to present characteristic difficulties for insertion device design, both in engineering detail and in operation. Perhaps the most critical problem, as observed, e.g., by Madey and co-workers in their initial FEL experiments, was the frequent quenching induced by scattered electrons upstream of their (bifilar) device. Postulating that this quenching was precipitated by directly-scattered or bremsstrahlung-induced particle energy deposited into the SC material or into material contiguous with it, the importance of numerical and experimental characterizations of this phenomenon for linac-based, user-facility SC undulator design becomes evident. In this paper we discuss selected prior experimental results and report on initial EGS4 code studies of scattered and bremsstrahlung induced particle energy deposition into SC structures with geometries comparable to a small-bore bifilar helical undulator.

  18. A Superconducting Magnet with Center Field of 10 T and φ100 mm Warm Bore

    Institute of Scientific and Technical Information of China (English)

    王秋良; 严陆光; 赵宝志; 宋守森

    2006-01-01

    A conduction-cooled superconducting magnet with central field of 10T and warm bore of 100 mm was designed based on a Nb3Sn and two NbTi superconducting coils. At the first stage, the NbTi coils have been fabricated and tested. A two-stage 4 K Gifford-McMahon (GM) cryocooler with the second-stage power in 1W, 4.2K is used to cool the magnet from room temperature to 4 K. The superconducting magnet with the same power supply has the operating current of 116A. The magnet can be rotated with a support frame to be operated with either horizontal or vertical position. A pair of Bi-2223 high temperature superconducting current leads was employed to reduce heat leakage into 4.2K level. The NbTi coils reachto the operating current of 120A without training effect to be observed during charging of the magnet during 40 minutes charging time and generate the center field of 6.5T. The training effect in the NbTi magnet directly cool-down by cryocooler and inter-winding support structure in magnet can be remarkably improved. The superconducting magnet has been stably operated for more than 275 hours with 6.5T. In this paper, the detailed design, fabrication, stress analysis and quench protection characteristics are presented.

  19. Simulation of rock fragmentation induced by a tunnel boring machine disk cutter

    Directory of Open Access Journals (Sweden)

    Huiyun Li

    2016-05-01

    Full Text Available A constitutive model based on the Johnson–Cook material model and the extended Drucker–Prager strength criterion was implemented in LS-DYNA to simulate the rock failure process induced by a single disk cutter of a tunnel boring machine. The normal, rolling, and side forces were determined by numerical tests. The simulation results showed that the normal and rolling forces increased with increasing penetration while the side force changed little. The normal force also increased under the conditions of confining pressures. The damage region of rock and cutting forces were also obtained by simulation of two disk cutters acting in tandem with different cutting spacings. The optimum ratio of cutter spacing to penetration depth determined from numerical modeling agrees well with that obtained by linear cutting machine tests. The average normal and rolling forces acting on the first cutter are slightly greater than those acting on the second when the cutting disk spacing is relatively small. The numerical modeling was verified to accurately capture the fragmentation of rock induced by disk cutter.

  20. Research on Dynamic Models and Performances of Shield Tunnel Boring Machine Cutterhead Driving System

    Directory of Open Access Journals (Sweden)

    Xianhong Li

    2013-01-01

    Full Text Available A general nonlinear time-varying (NLTV dynamic model and linear time-varying (LTV dynamic model are presented for shield tunnel boring machine (TBM cutterhead driving system, respectively. Different gear backlashes and mesh damped and transmission errors are considered in the NLTV dynamic model. The corresponding multiple-input and multiple-output (MIMO state space models are also presented. Through analyzing the linear dynamic model, the optimal reducer ratio (ORR and optimal transmission ratio (OTR are obtained for the shield TBM cutterhead driving system, respectively. The NLTV and LTV dynamic models are numerically simulated, and the effects of physical parameters under various conditions of NLTV dynamic model are analyzed. Physical parameters such as the load torque, gear backlash and transmission error, gear mesh stiffness and damped, pinions inertia and damped, large gear inertia and damped, and motor rotor inertia and damped are investigated in detail to analyze their effects on dynamic response and performances of the shield TBM cutterhead driving system. Some preliminary approaches are proposed to improve dynamic performances of the cutterhead driving system, and dynamic models will provide a foundation for shield TBM cutterhead driving system's cutterhead fault diagnosis, motion control, and torque synchronous control.

  1. Introducing passive acoustic filter in acoustic based condition monitoring: Motor bike piston-bore fault identification

    Science.gov (United States)

    Jena, D. P.; Panigrahi, S. N.

    2016-03-01

    Requirement of designing a sophisticated digital band-pass filter in acoustic based condition monitoring has been eliminated by introducing a passive acoustic filter in the present work. So far, no one has attempted to explore the possibility of implementing passive acoustic filters in acoustic based condition monitoring as a pre-conditioner. In order to enhance the acoustic based condition monitoring, a passive acoustic band-pass filter has been designed and deployed. Towards achieving an efficient band-pass acoustic filter, a generalized design methodology has been proposed to design and optimize the desired acoustic filter using multiple filter components in series. An appropriate objective function has been identified for genetic algorithm (GA) based optimization technique with multiple design constraints. In addition, the sturdiness of the proposed method has been demonstrated in designing a band-pass filter by using an n-branch Quincke tube, a high pass filter and multiple Helmholtz resonators. The performance of the designed acoustic band-pass filter has been shown by investigating the piston-bore defect of a motor-bike using engine noise signature. On the introducing a passive acoustic filter in acoustic based condition monitoring reveals the enhancement in machine learning based fault identification practice significantly. This is also a first attempt of its own kind.

  2. Disinfection of bore well water with chlorine dioxide/sodium hypochlorite and hydrodynamic cavitation.

    Science.gov (United States)

    Wang, Yifei; Jia, Aiyin; Wu, Yue; Wu, Chunde; Chen, Lijun

    2015-01-01

    The effect of hydrodynamic cavitation (HC) on potable water disinfection of chemicals was investigated. The bore well water was introduced into HC set-up to examine the effect of HC alone and combination of HC and chemicals such as chlorine dioxide and sodium hypochlorite. The effect of inlet pressure and geometrical parameters on disinfection was studied using HC alone and the results showed that increasing inlet pressure and using more and bigger holes of orifice plates can result in a higher disinfection rates. When HC was combined with chemicals, HC can reduce the doses of the chemicals and shorten the time of disinfection. It was also found that the decrease in bacteria concentration followed a first-order kinetic model. As for the experiment of combination of HC and sodium hypochlorite for disinfection, HC not only improves the disinfection rate but also degrades natural organic matter and chloroform. Compared with only sodium hypochlorite disinfection, combined processes get higher disinfection rate and lower production of chloroform, particularly the pretreatment with HC enhances the disinfection rate by 32% and there is a simultaneous reduction in production of chloroform by 39%.

  3. Modeling and Dynamic Analysis of Cutterhead Driving System in Tunnel Boring Machine

    Directory of Open Access Journals (Sweden)

    Wei Sun

    2017-01-01

    Full Text Available Failure of cutterhead driving system (CDS of tunnel boring machine (TBM often occurs under shock and vibration conditions. To investigate the dynamic characteristics and reduce system vibration further, an electromechanical coupling model of CDS is established which includes the model of direct torque control (DTC system for three-phase asynchronous motor and purely torsional dynamic model of multistage gear transmission system. The proposed DTC model can provide driving torque just as the practical inverter motor operates so that the influence of motor operating behavior will not be erroneously estimated. Moreover, nonlinear gear meshing factors, such as time-variant mesh stiffness and transmission error, are involved in the dynamic model. Based on the established nonlinear model of CDS, vibration modes can be classified into three types, that is, rigid motion mode, rotational vibration mode, and planet vibration mode. Moreover, dynamic responses under actual driving torque and idealized equivalent torque are compared, which reveals that the ripple of actual driving torque would aggravate vibration of gear transmission system. Influence index of torque ripple is proposed to show that vibration of system increases with torque ripple. This study provides useful guideline for antivibration design and motor control of CDS in TBM.

  4. Regressive approach for predicting bearing capacity of bored piles from cone penetration test data

    Directory of Open Access Journals (Sweden)

    Iyad S. Alkroosh

    2015-10-01

    Full Text Available In this study, the least square support vector machine (LSSVM algorithm was applied to predicting the bearing capacity of bored piles embedded in sand and mixed soils. Pile geometry and cone penetration test (CPT results were used as input variables for prediction of pile bearing capacity. The data used were collected from the existing literature and consisted of 50 case records. The application of LSSVM was carried out by dividing the data into three sets: a training set for learning the problem and obtaining a relationship between input variables and pile bearing capacity, and testing and validation sets for evaluation of the predictive and generalization ability of the obtained relationship. The predictions of pile bearing capacity by LSSVM were evaluated by comparing with experimental data and with those by traditional CPT-based methods and the gene expression programming (GEP model. It was found that the LSSVM performs well with coefficient of determination, mean, and standard deviation equivalent to 0.99, 1.03, and 0.08, respectively, for the testing set, and 1, 1.04, and 0.11, respectively, for the validation set. The low values of the calculated mean squared error and mean absolute error indicated that the LSSVM was accurate in predicting the pile bearing capacity. The results of comparison also showed that the proposed algorithm predicted the pile bearing capacity more accurately than the traditional methods including the GEP model.

  5. A methodology for laser diagnostics in large-bore marine two-stroke diesel engines

    Science.gov (United States)

    Hult, J.; Mayer, S.

    2013-04-01

    Large two-stroke diesel engines for marine propulsion offer several challenges to successful implementation of the laser diagnostic techniques applied extensively in smaller automotive engines. For this purpose a fully operational large-bore engine has been modified to allow flexible optical access, through 24 optical ports with clear diameters of 40 mm. By mounting the entire optical set-up directly to the engine, effects of the vigorous vibrations and thermal drifts on alignment can be minimized. Wide-angle observation and illumination, as well as relatively large aperture detection, is made possible through mounting of optical modules and relays inside optical ports. This allows positioning of the last optical element within 10 mm from the cylinder wall. Finally, the implementation on a multi-cylinder engine allows for flexible and independent operation of the optically accessible cylinder for testing purposes. The performance of the integrated optical engine and imaging system developed is demonstrated through laser Mie scattering imaging of fuel jet structures, from which information on liquid penetration and spray angles can be deduced. Double pulse laser-sheet imaging of native in-cylinder structures is also demonstrated, for the purpose of velocimetry.

  6. Numerical and experimental analysis of middle-bore copper-vapor laser discharge

    Science.gov (United States)

    Yu, Deli; Tao, Yongxiang; Yin, Xianhua; Chen, Lin; Yang, Yan; Li, Hailan; Wang, Runwen

    1998-08-01

    A single simulation model describing the discharge circuitry is introduced. First the differential equations are presented. In order to calculate the laser head discharge current, the thyratron resistance with a switching time coefficient (tau) s is investigated. The plasma conductivity used in these models is estimated using the available data on plasma parameters. Here 0.6 eV of the average electron temperature and 80 nH of thyratron inductance are assumed according to our previous model. The laser head discharge current of the differential equations is calculated with the method of Runge- Kutta. The discharge current profiles of the simulation are found to be in close agreement with the experimental data which come from 4.8-cm-diameter and 6.5-cm-diameter middle- bore Copper-Vapor Laser. In this way, the factors which effect the short rise time to increase lasing ability in the CVL (Copper-Vapor Laser) are studied on the bases of studying the storage capacitor's and the peaking capacitor's effect. As a calculation result, the inductance of the laser head takes an inferior effect to the thyratron circuit inductance on the discharge current rise time. Very good agreement exists between the calculated and measured results. This is a successful single discharge model.

  7. A Method Using Optical Contactless Displacement Sensors to Measure Vibration Stress of Small-Bore Piping.

    Science.gov (United States)

    Maekawa, Akira; Tsuji, Takashi; Takahashi, Tsuneo; Noda, Michiyasu

    2014-02-01

    In nuclear power plants, vibration stress of piping is frequently evaluated to prevent fatigue failure. A simple and fast measurement method is attractive to evaluate many piping systems efficiently. In this study, a method to measure the vibration stress using optical contactless displacement sensors was proposed, the prototype instrument was developed, and the instrument practicality for the method was verified. In the proposed method, light emitting diodes (LEDs) were used as measurement sensors and the vibration stress was estimated by measuring the deformation geometry of the piping caused by oscillation, which was measured as the piping curvature radius. The method provided fast and simple vibration estimates for small-bore piping. Its verification and practicality were confirmed by vibration tests using a test pipe and mock-up piping. The stress measured by both the proposed method and an accurate conventional method using strain gauges were in agreement, and it was concluded that the proposed method could be used for actual plant piping systems.

  8. Predator-prey interactions between shell-boring beetle larvae and rock-dwelling land snails.

    Directory of Open Access Journals (Sweden)

    Els Baalbergen

    Full Text Available Drilus beetle larvae (Coleoptera: Elateridae are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae species in Greece. We observe that Drilus species may be facultative or obligate Albinaria-specialists. We map geographically varying predation rates in Crete, where on average 24% of empty shells carry fatal Drilus bore holes. We also provide first-hand observations and video-footage of prey entry and exit strategies of the Drilus larvae, and evaluate the potential mutual evolutionary impacts. We find limited evidence for an effect of shell features and snail behavioral traits on inter- and intra-specifically differing predation rates. We also find that Drilus predators adjust their predation behavior based on specific shell traits of the prey. In conclusion, we suggest that, with these baseline data, this interesting predator-prey system will be available for further, detailed more evolutionary ecology studies.

  9. ZEDEX - A study of damage and disturbance from tunnel excavation by blasting and tunnel boring

    Energy Technology Data Exchange (ETDEWEB)

    Emsley, S. [Golder Associates, Maidenhead (United Kingdom); Olsson, Olle; Stenberg, L. [Swedish Nuclear Fuel and Waste Co., Figeholm (Sweden); Alheid, H.J. [Federal Inst. for Geosciences and Natural Resources, Hannover (Germany); Falls, S. [Queens Univ., Kingston, ON (Canada)

    1997-12-01

    The objectives of the ZEDEX project were to understand the mechanical behaviour of the excavation disturbed zone (EDZ) with respect to its origin, character, magnitude of property change, extent and its dependence on excavation method. Excavation with normal smooth blasting, blasting with low shock explosives and tunnel boring were studied. The drifts are located at Aespoe at a depth of 420 m, the profiles are circular and 5 m in diameter. The results have shown that there is a damaged zone, close to the drift wall dominated by changes in rock properties which are irreversible, and that there is a disturbed zone beyond the damaged zone that is dominated by changes in stress state and mainly reversible. There is no distinct boundary between the two zones. The results from ZEDEX indicate that the role of the EDZ as a preferential pathway to radionuclide transport is limited to the damaged zone. The extent of the damaged zone can be limited through application of appropriate excavation methods. By limiting the extent of the damaged zone it should also be feasible to block pathways in the damaged zone by plugs placed at strategic locations 68 refs, 92 figs, 31 tabs

  10. Generation of undular bores in the shelves of slowly-varying solitary waves.

    Science.gov (United States)

    El, G. A.; Grimshaw, R. H. J.

    2002-12-01

    We study the long-time evolution of the trailing shelves that form behind solitary waves moving through an inhomogeneous medium, within the framework of the variable-coefficient Korteweg-de Vries equation. We show that the nonlinear evolution of the shelf leads typically to the generation of an undular bore and an expansion fan, which form apart but start to overlap and nonlinearly interact after a certain time interval. The interaction zone expands with time and asymptotically as time goes to infinity occupies the whole perturbed region. Its oscillatory structure strongly depends on the sign of the inhomogeneity gradient of the variable background medium. We describe the nonlinear evolution of the shelves in terms of exact solutions to the KdV-Whitham equations with natural boundary conditions for the Riemann invariants. These analytic solutions, in particular, describe the generation of small "secondary" solitary waves in the trailing shelves, a process observed earlier in various numerical simulations. (c) 2002 American Institute of Physics.

  11. Performance of a 14-T CuNb/Nb3Sn Rutherford coil with a 300 mm wide cold bore

    Science.gov (United States)

    Oguro, Hidetoshi; Watanabe, Kazuo; Awaji, Satoshi; Hanai, Satoshi; Ioka, Shigeru; Sugimoto, Masahiro; Tsubouchi, Hirokazu

    2016-08-01

    A large-bore 14-T CuNb/Nb3Sn Rutherford coil was developed for a 25 T cryogen-free superconducting magnet. The magnet consisted of a low-temperature superconducting (LTS) magnet of NbTi and Nb3Sn Rutherford coils, and a high-temperature superconducting magnet. The Nb3Sn Rutherford coil was fabricated by the react-and-wind method for the first time. The LTS magnet reached the designed operation current of 854 A without a training quench at a 1 h ramp rate. The central magnetic field generated by the LTS magnet was measured by a Hall sensor to be 14.0 T at 854 A in a 300 mm cold bore.

  12. An alternative to the traveling-wave approach for use in two-port descriptions of acoustic bores

    Science.gov (United States)

    Ducasse, Eric

    2002-12-01

    For more than a decade, the digital waveguide model for musical instruments has been improved through the simulation of cylindrical and conical bores. But several difficulties remain, such as instabilities due to growing exponentials which appear when two conical bores are connected with decreasing taper. In this paper, an alternative overcoming these difficulties is proposed and can be extended to shapes other than cylinders, cones, and hyperbolic horns. A two-port model with more general state variables than usual traveling waves works efficiently for any shape without discontinuities in cross section. The equations for connecting separate elements at discontinuities make this two-port model appropriate for use in time domain simulation of the physical behavior of the wind instrument and its interactions with the player. The potential of this new approach is illustrated by several detailed examples.

  13. Development of 5 T NbTi Superconducting Magnet with 160 mm Warm Bore for Magnetic Separation

    Institute of Scientific and Technical Information of China (English)

    SHI Yi; WU Yu; LI Shaolei

    2008-01-01

    A wide-bore 5 T NbTi superconducting magnet,for magnetic separator,with an operational current of 106 A is designed and fabricated. This magnet with a φ60 mm room temperature bore is installed in a vacuum cryostat and immersed in liquid helium.A two-stage 4 K Gifford-McMahon (GM) cryocooler is used to maintain the cooling shield at 70 K and the condenser at 4 K in order to achieve the zero vaporization loss of liquid helium. The cooling power of the GM cryocooler is 1.5 W.In this paper,the design,heat leakage,stress analysis,quench protection characteristics and preliminary test results are presented.

  14. Cone penetration tests and soil borings at the Mason Road site in Green Valley, Solano County, California

    Science.gov (United States)

    Bennett, Michael J.; Noce, Thomas E.; Lienkaemper, James J.

    2011-01-01

    In support of a study to investigate the history of the Green Valley Fault, 13 cone penetration test soundings and 3 auger borings were made at the Mason Road site in Green Valley, Solano County, California. Three borings were made at or near two of the cone penetration test soundings. The soils are mostly clayey with a few sandy layers or lenses. Fine-grained soils range from low plasticity sandy lean clay to very plastic fat clay. Lack of stratigraphic correlation in the subsurface prevented us from determining whether any channels had been offset at this site. Because the soils are generally very clayey and few sand layers or lenses are loose, the liquefaction potential at the site is very low.

  15. "The defects of his race": E.G. Boring and antisemitism in American psychology, 1923-1953.

    Science.gov (United States)

    Winston, A S

    1998-02-01

    From the 1920s to the 1950s, Edwin G. Boring wrote letters of reference for Jewish students and colleagues in which he followed the common practice of identifying them as Jews and assessing whether they showed "objectionable traits" thought to characterize Jews. These practices are discussed in relation to the increasing antisemitism of the interwar period, with specific reference to Abraham A. Roback and Kurt Lewin. In Roback's case, the "defect" of Jewishness was thought to explain his undesirable personality: with Lewin, personal charm mitigated the "defect" of Jewishness. Boring's unsuccessful attempts to place Jewish students, his subsequent pessimism, and his postwar discussions of Jewish identity are examined in relation to the general issue of antisemitism in the history of academic psychology.

  16. North American Lauraceae: terpenoid emissions, relative attraction and boring preferences of redbay ambrosia beetle, Xyleborus glabratus (coleoptera: curculionidae: scolytinae.

    Directory of Open Access Journals (Sweden)

    Paul E Kendra

    Full Text Available The invasive redbay ambrosia beetle, Xyleborus glabratus, is the primary vector of Raffaelea lauricola, a symbiotic fungus and the etiologic agent of laurel wilt. This lethal disease has caused severe mortality of redbay (Persea borbonia and swampbay (P. palustris trees in the southeastern USA, threatens avocado (P. americana production in Florida, and has potential to impact additional New World species. To date, all North American hosts of X. glabratus and suscepts of laurel wilt are members of the family Lauraceae. This comparative study combined field tests and laboratory bioassays to evaluate attraction and boring preferences of female X. glabratus using freshly-cut bolts from nine species of Lauraceae: avocado (one cultivar of each botanical race, redbay, swampbay, silkbay (Persea humilis, California bay laurel (Umbellularia californica, sassafras (Sassafras albidum, northern spicebush (Lindera benzoin, camphor tree (Cinnamomum camphora, and lancewood (Nectandra coriacea. In addition, volatile collections and gas chromatography-mass spectroscopy (GC-MS were conducted to quantify terpenoid emissions from test bolts, and electroantennography (EAG was performed to measure olfactory responses of X. glabratus to terpenoids identified by GC-MS. Significant differences were observed among treatments in both field and laboratory tests. Silkbay and camphor tree attracted the highest numbers of the beetle in the field, and lancewood and spicebush the lowest, whereas boring activity was greatest on silkbay, bay laurel, swampbay, and redbay, and lowest on lancewood, spicebush, and camphor tree. The Guatemalan cultivar of avocado was more attractive than those of the other races, but boring response among the three was equivalent. The results suggest that camphor tree may contain a chemical deterrent to boring, and that different cues are associated with host location and host acceptance. Emissions of α-cubebene, α-copaene, α-humulene, and

  17. Intrinsic advantages of packed capillaries over narrow-bore columns in very high-pressure gradient liquid chromatography.

    Science.gov (United States)

    Gritti, Fabrice; McDonald, Thomas; Gilar, Martin

    2016-06-17

    250μm×100mm fused silica glass capillaries were packed with 1.8μm high-strength silica (HSS) fully porous particles. They were prepared without bulky stainless steel endfittings and metal frits, which both generate significant sample dispersion. The isocratic efficiencies and gradient peak capacities of these prototype capillary columns were measured for small molecules (n-alkanophenones) using a home-made ultra-low dispersive micro-HPLC instrument. Their resolution power was compared to that of standard 2.1mm×100mm very high-pressure liquid chromatography (vHPLC) narrow-bore columns packed with the same particles. The results show that, for the same column efficiency (25000 plates) and gradient steepness (0.04min(-1)), the peak capacity of the 250μm i.d. capillary columns is systematically 15-20% higher than that of the 2.1mm i.d. narrow-bore columns. A validated model of gradient chromatography enabled one to predict accurately the observed peak capacities of the capillary columns for non-linear solvation strength retention behavior and under isothermal conditions. Thermodynamics applied to the eluent quantified the temperature difference for the thermal gradients in both capillary and narrow-bore columns. Experimental data revealed that the gradient peak capacity is more affected by viscous heating than the column efficiency. Unlike across 2.1mm i.d. columns, the changes in eluent composition across the 250μm i.d. columns during the gradient is rapidly relaxed by transverse dispersion. The combination of (1) the absence of viscous heating and (2) the high uniformity of the eluent composition across the diameter of capillary columns explains the intrinsic advantage of capillary over narrow-bore columns in gradient vHPLC.

  18. 弹带挤进过程身管内壁损伤的数值模拟研究%Numerical simulation for gun barrel bore damage during shells with into bore

    Institute of Scientific and Technical Information of China (English)

    刘广生; 孙河洋; 周伟

    2015-01-01

    针对火炮发射过程中内膛的损伤、裂纹萌生和扩展问题,基于 HLC 细观损伤本构模型建立了相应的损伤力学有限元数值计算方法,将完全隐式应力更新算法与显式有限元计算相结合,通过用户自定义材料子程序 VUMAT 将损伤模型嵌入到有限元软件 ABAQUS /EXPLICIT 模块中。对某型火炮多发射击工况下内膛损伤破坏过程进行了数值模拟计算,分析了弹带挤进内膛过程中身管内壁材料性能随射弹发数变化的规律,并与实验进行了对比。结果表明:HLC细观损伤模型可以有效揭示身管内膛复杂的损伤行为并预测破裂缺陷,为火炮身管安全性设计提供有益的参考。%A damage mechanics finite element numerical computation method was established based on HLC microscopic damage model to solve problems of gun barrel bore damage,crack initialization and growth during gun firing. With this method,the completely implicit stress renewing algorithm was combined with the explicit finite element computation,the damage model was embedded into the finite element software ABAQUS /EXPLICIT module with a VUMAT subroutine.The damage and failure process of the barrel bore of a certain type of gun was simulated numerically during multiple rounds of firings.The law of the barrel bore material performance changing with the number of firing rounds was analyzed during shells with into bore and the simulated results were compared with the experimental ones.The results showed that HLC microscopic damage model can reveal the complicate damage behavior of the barrel bore and predict its cracking defects.The results provided a reference for safety design of gun barrels.

  19. Respiratory-Gated MRgHIFU in Upper Abdomen Using an MR-Compatible In-Bore Digital Camera

    Directory of Open Access Journals (Sweden)

    Vincent Auboiroux

    2014-01-01

    Full Text Available Objective. To demonstrate the technical feasibility and the potential interest of using a digital optical camera inside the MR magnet bore for monitoring the breathing cycle and subsequently gating the PRFS MR thermometry, MR-ARFI measurement, and MRgHIFU sonication in the upper abdomen. Materials and Methods. A digital camera was reengineered to remove its magnetic parts and was further equipped with a 7 m long USB cable. The system was electromagnetically shielded and operated inside the bore of a closed 3T clinical scanner. Suitable triggers were generated based on real-time motion analysis of the images produced by the camera (resolution 640×480 pixels, 30 fps. Respiratory-gated MR-ARFI prepared MRgHIFU ablation was performed in the kidney and liver of two sheep in vivo, under general anaesthesia and ventilator-driven forced breathing. Results. The optical device demonstrated very good MR compatibility. The current setup permitted the acquisition of motion artefact-free and high resolution MR 2D ARFI and multiplanar interleaved PRFS thermometry (average SNR 30 in liver and 56 in kidney. Microscopic histology indicated precise focal lesions with sharply delineated margins following the respiratory-gated HIFU sonications. Conclusion. The proof-of-concept for respiratory motion management in MRgHIFU using an in-bore digital camera has been validated in vivo.

  20. Deformation Compensation of Ram Components of Super-heavy-duty CNC Floor Type Boring and Milling Machine

    Institute of Scientific and Technical Information of China (English)

    WU Fenghe; QIAO Lijun; XU Yaoling

    2012-01-01

    Ram is a very important component of super-heavy-duty computer numerical control (CNC) floor type boring-milling machine,and deformation of ram is a significant source causing errors in machining process.To compensate the deformation error of super-heavy-duty CNC floor type boring-milling machine,based on force analysis theory,the law and compensation measures of deformation of ram are researched.Based on the principle of torque (force) balance of the ram components,the formulas of compensation forces and compensation torques are derived,the relations between compensation forces (compensation torques)and the stroke distance of the ram are given.According to theoretical analysis results and the structural characteristics of super-heavy-duty CNC floor type boring and milling machine of TK6932,rods compensation,hydrostatic pressure compensation and wire rope compensation measures are taken to compensate the deformation error of ram.The experiments and computer simulation results show that the straightness of the ram at its overhanging end meets the national machinery industry standards.

  1. Traps and attractants for wood-boring insects in ponderosa pine stands in the Black Hills, South Dakota.

    Science.gov (United States)

    Costello, Sheryl L; Negrón, José F; Jacobi, William R

    2008-04-01

    Recent large-scale wildfires have increased populations of wood-boring insects in the Black Hills of South Dakota. Because little is known about possible impacts of wood-boring insects in the Black Hills, land managers are interested in developing monitoring techniques such as flight trapping with semiochemical baits. Two trap designs and four semiochemical attractants were tested in a recently burned ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in the Black Hills. Modified panel and funnel traps were tested in combination with the attractants, which included a woodborer standard (ethanol and alpha-pinene), standard plus 3-carene, standard plus ipsenol, and standard plus ipsdienol. We found that funnel traps were equally efficient or more efficient in capturing wood-boring insects than modified panel traps. Trap catches of cerambycids increased when we added the Ips spp. pheromone components (ipsenol or ipsdienol) or the host monoterpene (3-carene) to the woodborer standard. During the summers of 2003 and 2004, 18 cerambycid, 14 buprestid, and five siricid species were collected. One species of cerambycid, Monochamus clamator (LeConte), composed 49 and 40% of the 2003 and 2004 trap catches, respectively. Two other cerambycids, Acanthocinus obliquus (LeConte) and Acmaeops proteus (Kirby), also were frequently collected. Flight trap data indicated that some species were present throughout the summer, whereas others were caught only at the beginning or end of the summer.

  2. Interpretation of Geological Correlation Borings 1, 2, 3 in the A/M Area of the Savannah River Site, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Wyatt, D.E. [Westinghouse Savannah River Company, AIKEN, SC (United States); Cumbest, R.J.; Aadland, R.K.; Syms, F.H.; Stephenson, D.E.; Sherrill, J.C.

    1997-06-01

    The Geophysical Correlation Boring (GCB) Program was organized to provide a comprehensive correlation capability between geological core and advanced borehole geophysical data, surface high resolution reflection seismic information and, when available, borehole geochemical and cone penetrometer data. This report provides results and initial geological interpretations of borings one, two, and three (GCB-1, GCB-2, GCB-3) located within the Upper Three Runs Watershed (A/M Area) of the Savannah River Site.

  3. Novel fiber-based technique for inspection of holes in narrow-bore tubes

    Science.gov (United States)

    Bernard, Fabien; Flaherty, Tony; O'Connor, Gerard M.

    2009-06-01

    Optical tools offer a route to increasing throughput and efficiency in industrial inspection operations, one of the most time-consuming and labour-intensive aspects of modern manufacturing. One prominent example in the medical device industry is inspection of drilled holes, particularly in narrow-bore tubes (precision-flow devices, such as catheters for drug delivery, radio-opaque contrast agents, etc). The products in which these holes feature are increasing in complexity (reduced dimensions, increasing number of drilled features- in some products now reaching into the hundreds). These trends present a number of technical challenges, not least to ensure that holes are completed and that no damage to the part occurs as a result of over-drilling, for example. This paper will present a novel sensor based on back-side illumination of the drilled hole using side-glowing optical fibers to detect, qualify and quantify drilled holes. The concept is based on inserting a laser-coupled side-glowing optical fiber into the lumen of the tube to be drilled, and imaging the light emitted from this fiber through a drilled hole using a vision system mounted external to the tube. The light from the fiber allows rapid determination of hole completion, shape and size, as well as quantity in the case of products with multiple holes. If the fiber is mounted in the tube prior to drilling, the light emitted from the fiber can be used as a real-time hole breakthrough sensor, preventing under or overdrilling of the tube.

  4. An experimental and computational investigation of electrical resistivity imaging for prediction ahead of tunnel boring machines

    Science.gov (United States)

    Schaeffer, Kevin P.

    Tunnel boring machines (TBMs) are routinely used for the excavation of tunnels across a range of ground conditions, from hard rock to soft ground. In complex ground conditions and in urban environments, the TBM susceptible to damage due to uncertainty of what lies ahead of the tunnel face. The research presented here explores the application of electrical resistivity theory for use in the TBM tunneling environment to detect changing conditions ahead of the machine. Electrical resistivity offers a real-time and continuous imaging solution to increase the resolution of information along the tunnel alignment and may even unveil previously unknown geologic or man-made features ahead of the TBM. The studies presented herein, break down the tunneling environment and the electrical system to understand how its fundamental parameters can be isolated and tested, identifying how they influence the ability to predict changes ahead of the tunnel face. A proof-of-concept, scaled experimental model was constructed in order assess the ability of the model to predict a metal pipe (or rod) ahead of face as the TBM excavates through a saturated sand. The model shows that a prediction of up to three tunnel diameters could be achieved, but the unique presence of the pipe (or rod) could not be concluded with certainty. Full scale finite element models were developed in order evaluate the various influences on the ability to detect changing conditions ahead of the face. Results show that TBM/tunnel geometry, TBM type, and electrode geometry can drastically influence prediction ahead of the face by tens of meters. In certain conditions (i.e., small TBM diameter, low cover depth, large material contrasts), changes can be detected over 100 meters in front of the TBM. Various electrode arrays were considered and show that in order to better detect more finite differences (e.g., boulder, lens, pipe), the use of individual cutting tools as electrodes is highly advantageous to increase spatial

  5. Closed-bore XMR (CBXMR) systems for aortic valve replacement: X-ray tube imaging performance

    Energy Technology Data Exchange (ETDEWEB)

    Bracken, John A.; Komljenovic, Philip; Lillaney, Prasheel V.; Fahrig, Rebecca; Rowlands, J. A. [Department of Medical Biophysics and Sunnybrook Health Sciences Center, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Medical Biophysics and Sunnybrook Health Sciences Center, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada)

    2009-04-15

    A hybrid closed-bore x-ray/MRI system (CBXMR) is proposed to improve the safety and efficacy of percutaneous aortic valve replacement procedures. In this system, an x-ray C-arm will be positioned about 1 m from the entrance of a 1.5 T MRI scanner. The CBXMR system will harness the complementary strengths of both modalities to guide and deploy a bioprosthetic valve into the aortic annulus of the heart without coronary artery obstruction. A major challenge in constructing this system is ensuring proper operation of a rotating-anode x-ray tube in the MRI magnetic fringe field environment. The electron beam in the x-ray tube responsible for producing x rays can be deflected by the fringe field. However, the clinical impact of electron beam deflection in a magnetic field has not yet been studied. Here, the authors investigated changes in focal spot resolving power, field of view shift, and field of view truncation in x-ray images as a result of electron beam deflection. The authors found that in the fringe field acting on the x-ray tube at the clinical location for the x-ray C-arm (4 mT), focal spot size increased by only 2%, so the fringe field did not limit the resolving power of the x-ray system. The magnetic field also caused the field of view to shift by 3 mm. This shift must be corrected to avoid unnecessary primary radiation exposure to the patient and the staff in the cardiac catheterization laboratory. The fringe field was too weak to cause field of view truncation.

  6. Commissioning and quality control of a dedicated wide bore 3T MRI simulator for radiotherapy planning

    Directory of Open Access Journals (Sweden)

    Aitang Xing

    2016-06-01

    Full Text Available Purpose: The purpose of this paper is to describe a practical approach to commissioning and quality assurance (QA of a dedicated wide-bore 3 Tesla (3T magnetic resonance imaging (MRI scanner for radiotherapy planning.Methods: A comprehensive commissioning protocol focusing on radiotherapy (RT specific requirements was developed and performed. RT specific tests included: uniformity characteristics of radio-frequency (RF coil, couch top attenuation, geometric distortion, laser and couch movement and an end-to-end radiotherapy treatment planning test. General tests for overall system performance and safety measurements were also performed.Results: The use of pre-scan based intensity correction increased the uniformity from 61.7% to 97% (body flexible coil, from 50% to 90% (large flexible coil and from 51% to 98% (small flexible coil. RT flat top couch decreased signal-to-noise ratio (SNR by an average of 42%. The mean and maximum geometric distortion was found to be 1.25 mm and 4.08 mm for three dimensional (3D corrected image acquisition, 2.07 mm and 7.88 mm for two dimensional (2D corrected image acquisition over 500 mm × 375 mm × 252 mm field of view (FOV. The accuracy of the laser and couch movement was less than ±1 mm. The standard deviation of registration parameters for the end-to-end test was less than 0.41 mm. An on-going QA program was developed to monitor the system’s performance.Conclusion: A number of RT specific tests have been described for commissioning and subsequent performance monitoring of a dedicated MRI simulator (MRI-Sim. These tests have been important in establishing and maintaining its operation for RT planning.

  7. High-field open versus short-bore magnetic resonance imaging of the spine: a randomized controlled comparison of image quality.

    Directory of Open Access Journals (Sweden)

    Judith Enders

    Full Text Available BACKGROUND: The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. METHODS: Altogether, 93 (80% women, mean age 53 consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR and contrast-to-noise ratios (CNR, and quantitative contour sharpness. RESULTS: The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34-37% for the quantitative contour sharpness (P<0.0001. The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001. CONCLUSIONS: In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. TRIAL REGISTRATION: ClinicalTrials.gov NCT00715806.

  8. The use of a Tunnel Boring Machine (TBM) as a seismic source

    Science.gov (United States)

    Kreutzer, Ingrid; Chwatal, Werner; Radinger, Alexander; Brückl, Ewald

    2014-05-01

    The Tunnel Seismic While Drilling (TSWD) method uses the Tunnel Boring Machine (TBM) as the seismic source. The method has been developed to predict the geological situation from reflections ahead of the tunnel face without disturbing the tunneling. The vibrations of the TBM are continuously monitored near the drilling head (pilot signal) as well as the direct and reflected seismic wave field at borehole geophones (geophone signal) situated in the tunnel wall behind the TBM. During the processing these signals are correlated and result in excellent seismic traces comparable to conventional seismic methods. The interpretation of the reflections leads to a nearly daily prognosis about 100 m ahead of the TBM. This system was successfully implemented at three different construction sites in Austria and is currently operating at one further. The cutters on front of the TBM head are pressed against the tunnel face and split the rock during rotating which is called the chipping process. This cutting process generates seismic waves radiated into the rock mass and results also in vibrations of the TBM itself. On the one hand it is important to know the source mechanism of the TBM and the radiation pattern of the seismic waves in all directions. Until now this is not well understood. To investigate this 3C-geophones were installed at the surface above the tunnel axis at different construction sites. The obtained seismograms show the forward and backward radiated seismic wave field of the TBM, for the present without consideration of the influence of the free surface. We compare this data with modelled seismograms in which we use different possible source mechanism, like single force or force due to tensile cracks. First results are shown in the scope of this work. On the other hand it is essential to know how good the recorded pilot signal represents the entire chipping process. Due to technically reasons the pilot signal has been registered so far on the non-rotating part

  9. Anatomical study on Myoforceps aristatus, an invasive boring bivalve in S.E. Brazilian coast (Mytilidae

    Directory of Open Access Journals (Sweden)

    Luiz Ricardo L. Simone

    2006-01-01

    Full Text Available The bivalve Myoforceps aristatus (Dillwyn, 1817, also known as Lithophaga aristata, have been recently collected in the coasts of Rio de Janeiro and São Paulo, Brazil; a species that bores shells of other mollusks. This occurrence has been interpreted as an invasion of this species, originally from the Caribbean. The distinguishing character of the species is the posterior extensions of the shell crossing with each other. Because specimens with this character have also been collected in the Pacific Ocean, they all have been considered a single species. However, it is possible that more than one species may be involved in such worldwide distribution. With the objective of providing full information based on Atlantic specimens, a complete anatomical description is provided, which can be used in comparative studies with specimens from other oceans. Additional distinctive features of M. aristatus are the complexity of the incurrent siphon, the kidney opening widely into the supra-branchial chamber (instead of via a nephropore, and the multi-lobed auricle.O bivalve Myoforceps aristatus (Dillwyn, 1817, também conhecido como Lithophaga aristata, tem sido recentemente coletado nas costas do Rio de Janeiro e São Paulo, Brasil; uma espécie que perfura conchas de outros moluscos. Esta ocorrência está sendo interpretada como uma invasão de uma espécie originada do Caribe. O caráter distintivo da espécie é a região posterior da concha, com extensões que se cruzam. Como espécimes com esta característica também têm sido coletados no oceano Pacífico, eles tem sido considerados como pertencentes à mesma espécie. Entretanto, é possível que mais de uma espécie possam estar envolvidas nesta suposta distribuição mundial. Com o objetivo de fornecer informação completa baseada em material do Atlântico, uma descrição anatômica completa é dada, a qual pode ser usada em estudos comparativos com espécimes de outros oceanos. As caracter

  10. Electro-Pulse-Boring (EPB):Novel Super-Deep Drilling Technology for Low Cost Electricity

    Institute of Scientific and Technical Information of China (English)

    Hans O.Schiegg; Arild Rdland; Guizhi Zhu; David A Yuen

    2015-01-01

    The inexhaustible heat deposit in great depths (5–10 km) is a scientific fact. Such deposit occurs around the globe. Thereby, everybody is enabled to generate autonomously clean and renew-able energy, ample electricity and heat. The economical exploration and exploitation of this super-deep geothermal heat deposit requires a novel drilling technique, because the currently only deep drilling method (Rotary) is limited to about 5 km, due to the rising costs, depending exponentially on depth. Electro-pulse-boring (EPB) is a valuable option to Rotary drilling. EPB, originally investigated in Russia, is ready to be developed for industrialization. The feasibility of EPB is proven by many boreholes drilled up to 200 m in granite (crystalline). Estimates show outstanding low costs for drilling by EPB: 100€/m for a borehole with a large diameter (Ø) such as 20"(50 cm), independent on depth and applicable likewise for sediments and crystalline rocks, such as granite. The current rate of pene-tration (ROP) of 3 m per hour is planned to be augmented up to 35 m per hour, and again, irrespec-tive whether in sedimentary or crystalline formations. Consequently, a 10 km deep borehole with Ø 50 cm will ultimately be drilled within 12 days. EPB will create new markets, such as: (i) EPB shallow drilling for geotechnics, energy piles, measures in order to mitigate natural hazards, etc., (ii) EPB deep drilling (3–5 km) for hydro-geothermics, exploration campaigns etc. and (iii) EPB super-deep drilling (5–10 km) for petro-geothermics, enabling the economic generation of electricity. The autonomous and unlimited supply with cost efficient electricity, besides ample heat, ensures reliably clean and renew-able energy, thus, high supply security. Such development will provide a substantial relief to cope with the global challenge to limit the climate change below 2 ºC. The diminution of fossil fuels, due to the energy transition in order to mitigate the climate change, implies

  11. Caldecott 4th bore tunnel project: influence of ground water flows and inflows triggered by tectonic fault zones?

    Science.gov (United States)

    Neuhuber, G.; G. Neuhuber1, W. Klary1, A. Nitschke1, B. Thapa2, Chris Risden3, T. Crampton4, D. Zerga5

    2011-12-01

    The 4th Bore is a highway tunnel on California State Route 24 currently under construction. The 4th Bore is undertaken by the California State Department of Transportation (CALTRANS) and the Contra Costa County Transportation Commission (CCTC) to alleviate traffic congestion on SR24 connecting the cities of Oakland and Orinda in the San Francisco East Bay Area. The cost for the 4th Bore is estimated at $ 390.8 Mill. The 3,249 ft long 4th Bore tunnel will have excavated dimensions of approximately 40 ft height and 49 ft width. A total of 7 cross passages will run between the 3rd and the new 4th bore. Geology and Hydrogeology: The project is located in the Oakland Berkeley Hills of the SF Bay Area. The Caldecott Tunnels lie within the easterly assemblage of the Hayward fault zone province which consists of a sequence of sedimentary and volcanic rocks that accumulated in the interval between about 16 and 8.4 Ma (Miocene). The basal rocks of these Tertiary deposits consist of deep marine basin sediments of the Monterey Group. These rocks are overlain uncomfortably by an interbedded sequence of terrestrial sediments (Orinda Formation) and volcanic rocks (Moraga Formation). The Tertiary rocks have been folded into large amplitude, NW trending folds that are cut by N trending strike and slip faults. The SF Bay Region, which is crossed by 4 major faults (San Gregorio, San Andreas, Hayward, and Calaveras), is considered one of the more seismically active regions of the world. The active Hayward fault lies 0.9mi to the west of the Caldecott Tunnels and is the closest major fault to the project area. The tunnel is at the moment under top heading construction: West Portal (360ft) and East Portal (1,968.5ft). While major faults typically influence groundwater flow, characterization of such influences is extremely difficult because of the heterogeneity of the hydraulic systems and the different lithological parameters and influences. Four major inactive fault zones striking

  12. Wrong detection of ventricular fibrillation in an implantable cardioverter defibrillator caused by the movement near the MRI scanner bore.

    Science.gov (United States)

    Mattei, Eugenio; Censi, Federica; Triventi, Michele; Mancini, Matteo; Napolitano, Antonio; Genovese, Elisabetta; Cannata, Vittorio; Falsaperla, Rosaria; Calcagnini, Giovanni

    2015-01-01

    The static magnetic field generated by MRI systems is highly non-homogenous and rapidly decreases when moving away from the bore of the scanner. Consequently, the movement around the MRI scanner is equivalent to an exposure to a time-varying magnetic field at very low frequency (few Hz). For patients with an implanted cardiac stimulators, such as an implantable cardioverter/defibrillator (ICD), the movements inside the MRI environment may thus induce voltages on the loop formed by the leads of the device, with the potential to affect the behavior of the stimulator. In particular, the ICD's detection algorithms may be affected by the induced voltage and may cause inappropriate sensing, arrhythmia detections, and eventually inappropriate ICD therapy.We performed in-vitro measurements on a saline-filled humanshaped phantom (male, 170 cm height), equipped with an MRconditional ICD able to transmit in real-time the detected cardiac activity (electrograms). A biventricular implant was reproduced and the ICD was programmed in standard operating conditions, but with the shock delivery disabled. The electrograms recorded in the atrial, left and right ventricle channels were monitored during rotational movements along the vertical axis, in close proximity of the bore. The phantom was also equipped with an accelerometer and a magnetic field probe to measure the angular velocity and the magnetic field variation during the experiment. Pacing inhibition, inappropriate detection of tachyarrhythmias and of ventricular fibrillation were observed. Pacing inhibition began at an angular velocity of about 7 rad/s, (dB/dt of about 2 T/s). Inappropriate detection of ventricular fibrillation occurred at about 8 rad/s (dB/dt of about 3 T/s). These findings highlight the need for a specific risk assessment of workers with MR-conditional ICDs, which takes into account also effects that are generally not considered relevant for patients, such as the movement around the scanner bore.

  13. Design, Fabrication and Initial Testing of a Large Bore Single Aperture 1 m Long Superconducting Dipole Made with Phenolic Inserts

    CERN Document Server

    Boschmann, H; Kirby, G A; Lucas, J; Ostojic, R; Russenschuck, Stephan; Siemko, A; Vanenkov, I; Weterings, W

    1997-01-01

    In the framework of the LHC magnet development programme, a large bore single aperture 1-meter long superconducting dipole has been built in collaboration with HOLEC. The magnet features a single layer coil wound using the LHC main dipole outer layer cable, phenolic inserts, and a keyed two part structural iron yoke. This paper presents the magnetic and mechanical design and optimisation of the magnet. We describe the coil winding and curing, and present the construction and assembly procedures. Finally we report on the mechanical behaviour during assembly and cooling, and present the magnet training behaviour.

  14. 岩溶地质钻孔桩施工技术%Karst Geology Bored Pile Construction Technique

    Institute of Scientific and Technical Information of China (English)

    程军

    2012-01-01

    According to the Karat geological structure features, the article describes the treating points of bridge bored pile construction in Karat geology, and presents different Karat geological structures.%针对卡斯特地区的地质构成特点,本文主要论述了岩溶地质条件下的桥梁钻孔桩施工根据其不同类别分类处理要点控制,并简要的对岩溶地质不同的结构情况予以了说明.

  15. Pulsed ion sheath dynamics in a cylindrical bore for inner surface grid-enhanced plasma source ion implantation

    CERN Document Server

    Wang Jiu Li; Fan Song Hua; Yang Wu Bao; Yang Size

    2002-01-01

    Based on authors' recently proposed grid-enhanced plasma source ion implantation (GEPSII) technique for inner surface modification of materials with cylindrical geometry, the authors present the corresponding theoretical studies of the temporal evolution of the plasma ion sheath between the grid electrode and the target in a cylindrical bore. Typical results such as the ion sheath evolution, time-dependent ion density and time-integrated ion energy distribution at the target are calculated by solving Poisson's equation coupled with fluid equations for collisionless ions and Boltzmann assumption for electrons using finite difference methods. The calculated results can further verify the feasibility and superiority of this new technique

  16. Hydraulic resistance to movement of a drill suspended by a cable in a bore-hole in travels

    OpenAIRE

    Vasiliev,N.I./Kudryashov, B.B.

    2002-01-01

    Equations are given for calculation of the hydraulic resistance force to movement of a drill suspended by cable and the speed of its movement as a function of the dimension and mass of the drill and properties of the hole liquid. The most significant factor influencing the hydraulic resistance during drill movement in the hole is the radial clearance between the drill and bore-hole walls. The methods of experimental study of the drill movement on the laboratory stand are described. The result...

  17. 一种可调镗刀刀杆的设计与应用%An Adjustment Of The Design And Application Of The Boring Tool Arbor

    Institute of Scientific and Technical Information of China (English)

    黄祥; 徐俊; 于辉

    2012-01-01

    Hole boring is a common method in Machinery Manufacturing. Its main advantage lies in guaranteeing precision of a hole in a quite good manner. As for some parts, such as a box, there are many holes and holes with different apertures. In the process of boring operations, various specifications of boring knife are needed and knife adjusting time is added. The design of an adjustable boring arbor with cutter mainly includes coarse and precise adjustment of swallowtail pair, stepper motor pair, and worm -gear pair. After coarse and precise adjustment, shanks' length can be adjusted to realize boring operations of holes with different diameters and depths. Moreover, direction between linking shanks and shanks of boring knife could be changed to bore inner holes in different places. Adjustable boring arbor could further enlarge coverage of boring operations and possesses a high application Value.%镗孔是机械制造中常用的方法,主要优点在于能很好地保证孔的位置精度。对于有的零件如箱体等,孔多且孔径大多不同,在镗削加工时,就需要多种规格的镗刀,也增加了对刀时问。设计一种可调式镗刀刀杆,主要包括燕尾导轨副、丝杠螺母副和蜗轮蜗杆副的粗调与微调机构等部分,通过粗调和微调机构的工作,可以实现刀杆伸出长度的调整,完成对不同直径和深度孔的镗削加工。另外,还可以变换连接杆和镗刀杆的方位,镗削位置不同的内孔。进一步扩大镗削加工的范围,具有很高的应用价值。

  18. Machining of Crankshaft and Camshaft Bores%缸体曲轴孔和凸轮轴孔的加工方法

    Institute of Scientific and Technical Information of China (English)

    程权

    2014-01-01

    The process of machining the crankshaft and camshaft bores of an engine was analyzed according totheir structure features, technical requirements and production conditions. The key issue was how todesign and manufacture the boring tools and fixtures that can attain the required precisions of the bores. Optimal design and proper processing were made for making the boring fixture that can ensure the quality of the crankshaft and camshaft bores.%介绍了某型柴油机缸体曲轴孔、凸轮轴孔的结构特点和技术要求,分析了加工工艺,重点阐述了镗夹具的设计制造过程,通过优选设计方案和选用合理的工艺方法,来保证镗夹具的质量满足曲轴孔和凸轮轴孔高精度的加工要求。

  19. Evaluación de tres dietas con harina de hoja de bore (Alocasia macrorrhiza en pollos de engorde

    Directory of Open Access Journals (Sweden)

    Fredy López M.

    2012-12-01

    Full Text Available Objetivo. Evaluar el efecto nutricional de incluir la harina de hoja de bore, en proporciones de 0 (T1, 5 (T2, 10 (T3 y 15% (T4, en la alimentación de 100 pollos machos de la línea Ross 308. Materiales y Métodos. Se empleo un diseño experimental completamente al azar con cuatro tratamientos, cinco repeticiones por tratamiento y cinco unidades experimentales por repetición. Para su respectivo análisis se registró consumo diario, ganancia de peso, conversión alimenticia, mortalidad y eficiencia económica, durante un periodo de 6 semanas. Resultados. Se observó que no existieron diferencias estadísticas significativas en conversión alimenticia, pero si en consumo, ganancia de peso y eficiencia económica (p< 0.05, siendo el mejor tratamiento el T2, con un consumo de 4003.4 g, una ganancia de peso de 1794.4g una conversión de 2.4 y un beneficio neto de campo de 107.88%. Conclusiones. La harina de hoja de bore es una alternativa de alimentación para pollos de engorde, al emplearla al 5% de nivel de inclusión, como materia prima no convencional, la cual permite generar un buen comportamiento productivo y económico.

  20. 镗床多功能刀架设计%Design of the Muitifunctional Tool Rest for the Boring Machine

    Institute of Scientific and Technical Information of China (English)

    尹业宏; 安宁; 刘小鹏

    2012-01-01

    针对没有平旋盘的镗床在加工过程中无法调整镗刀的径向进给量问题,通过对径向进刀系统传动链的运动分析和计算,设计一种镗床多功能刀架.使用该刀架能在主轴旋转的同时,手动或自动调节镗刀的径向进给量.并采用Pro/E软件建立了刀架的三维模型.使用该刀架能极大地方便加工操作,提高机床的加工效率.%Aiming at the question that the radial feed rate unable adjusted during processing of boring mills without flat spin dish, on the basis of analyzing and calculating the movement of the drive chain of radial feeding system, a multifunctional tool rest was designed with which the radial feed rate of a boring cutter could be adjusted manually or automatically while the main axis was rotating. By using the Pro/E software, the three-dimension model was built. By this method, the operation process and machining efficiency of the machine tool are improved substantially.

  1. The Crosshole Sonic Logging (CSL) Measurement System to Measure the Quality of Physical Model of Bored Pile

    Science.gov (United States)

    Sibit, Denniswara; Handayani, Gunawan

    2016-08-01

    The crosshole sonic logging measurement to measure the quality of bored piles is presented in this paper. The development of crosshole measurement system on physical bored pile modeling was carried out. The diameter of the concrete model was around 1 m and the height of the model was 1 m. In the model two holes were constructed to simulate the crosshole measurement system in the field. The two holes were filled with water and then two transducers were lowered in the holes. The transducers were built from audio speaker and microphone and they were sealed by rubber material so that the transducers were water proof. The speaker transducer acted as transmitter and the microphone transducer acted as receiver. The acoustic wave transmitted from the speaker penetrated in the concrete material and received by receiver. By analyzing the waveform arrived at the receiver by means of datalogger we determine the condition the concrete pile i.e. whether there were cavities in the concrete etc.

  2. Seismically induced soft-sediment deformation structures revealed by X-ray computed tomography of boring cores

    Science.gov (United States)

    Nakashima, Yoshito; Komatsubara, Junko

    2016-06-01

    X-ray computed tomography (CT) allows us to visualize three-dimensional structures hidden in boring cores nondestructively. We applied medical X-ray CT to cores containing seismically induced soft-sediment deformation structures (SSDSs) obtained from the Kanto region of Japan, where the 2011 off the Pacific coast of Tohoku Earthquake occurred. The CT images obtained clearly revealed various types of the seismically induced SSDSs embedded in the cores: a propagating sand dyke bent complexly by the preexisting geological structure, deformed laminations of fluidized sandy layers, and two types of downward mass movement (ductile downward folding and brittle normal faulting) as compensation for upward sand transport through sand dykes. Two advanced image analysis techniques were applied to the sand dyke CT images for the first time. The GrowCut algorithm, a specific digital image segmentation technique that uses cellular automata, was used successfully to extract the three-dimensional complex sand dyke structures embedded in the sandy sediments, which would have been difficult to achieve using a conventional image processing technique. Local autocorrelation image analysis was performed to detect the flow pattern aligned along the sand dykes objectively. The results demonstrate that X-ray CT coupled with advanced digital image analysis techniques is a promising approach to studying the seismically induced SSDSs in boring cores.

  3. PLC Transformation of T68 Boring Lathe%T68镗床的 PLC 改造

    Institute of Scientific and Technical Information of China (English)

    孙小春

    2015-01-01

    This paper describes the transformation of T68 boring lathe with Mitsubishi FX1S series PLC ,and states the transfor‐ming scheme of the system ,meantime ,according to the working requirements and characteristics of T68 boring lathe ,the as‐signments of PLC input and output was confirmed .The defects of relay control circuits were improved ,and a ladder diagram was designed and spot adjustment was performed .%介绍了利用三菱FX1S系列PLC对T68镗床的改造,阐述了系统的改造方案,同时配合T68镗床的工作要求和特点,确定了 PLC的输入输出分配,改进了原有继电器控制电路的缺陷,设计出梯形图并进行现场调试。

  4. New Rock Abrasivity Test Method for Tool Life Assessments on Hard Rock Tunnel Boring: The Rolling Indentation Abrasion Test (RIAT)

    Science.gov (United States)

    Macias, F. J.; Dahl, F.; Bruland, A.

    2016-05-01

    The tunnel boring machine (TBM) method has become widely used and is currently an important presence within the tunnelling industry. Large investments and high geological risk are involved using TBMs, and disc cutter consumption has a great influence on performance and cost, especially in hard rock conditions. Furthermore, reliable cutter life assessments facilitate the control of risk as well as avoiding delays and budget overruns. Since abrasive wear is the most common process affecting cutter consumption, good laboratory tests for rock abrasivity assessments are needed. A new abrasivity test method by rolling disc named Rolling Indentation Abrasion Test (RIAT) has been developed. The goal of the new test design and procedure is to reproduce wear behaviour on hard rock tunnel boring in a more realistic way than the traditionally used methods. Wear by rolling contact on intact rock samples is introduced and several rock types, covering a wide rock abrasiveness range, have been tested by RIAT. The RIAT procedure indicates a great ability of the testing method to assess abrasive wear on rolling discs. In addition and to evaluate the newly developed RIAT test method, a comprehensive laboratory testing programme including the most commonly used abrasivity test methods and the mineral composition were carried out. Relationships between the achieved results from conventional testing and RIAT results have been analysed.

  5. Distraction and task engagement: How interesting and boring information impact driving performance and subjective and physiological responses.

    Science.gov (United States)

    Horrey, William J; Lesch, Mary F; Garabet, Angela; Simmons, Lucinda; Maikala, Rammohan

    2017-01-01

    As more devices and services are integrated into vehicles, drivers face new opportunities to perform additional tasks while driving. While many studies have explored the detrimental effects of varying task demands on driving performance, there has been little attention devoted to tasks that vary in terms of personal interest or investment-a quality we liken to the concept of task engagement. The purpose of this study was to explore the impact of task engagement on driving performance, subjective appraisals of performance and workload, and various physiological measurements. In this study, 31 participants (M = 37 yrs) completed three driving conditions in a driving simulator: listening to boring auditory material; listening to interesting material; and driving with no auditory material. Drivers were simultaneously monitored using near-infrared spectroscopy, heart monitoring and eye tracking systems. Drivers exhibited less variability in lane keeping and headway maintenance for both auditory conditions; however, response times to critical braking events were longer in the interesting audio condition. Drivers also perceived the interesting material to be less demanding and less complex, although the material was objectively matched for difficulty. Drivers showed a reduced concentration of cerebral oxygenated hemoglobin when listening to interesting material, compared to baseline and boring conditions, yet they exhibited superior recognition for this material. The practical implications, from a safety standpoint, are discussed.

  6. Influence of pressure conditions and back-filling materials on the durability of bore-hole ground loops; Lebensdauer von Erdwaermesonden in Bezug auf Druckverhaeltnisse und Hinterfuellung

    Energy Technology Data Exchange (ETDEWEB)

    Rohner, R. [E. Rohner, Arnegg (Switzerland); Rybach, L.; Salton, M. [Swiss Federal Institute of Technology (ETHZ), Institut fuer Geophysik, Zuerich (Switzerland)

    2001-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) discusses the influence of the relatively high pressures found in ground loops at depths of more than 200 metres and the effects caused by overloading the ground loops. The latter can cause the back-filling between the ground loop and the surrounding rock to freeze. The report describes tests carried out on 70-metre and 265-metre deep test bore-hole installations. The results of investigations into the influence of such pressure conditions on the materials of the ground loop and their service life are presented. The results are also compared with simulations using the FRACTure and EED calculation programmes. Details are given on the bore-holes with respect to their geology and construction. The report concludes that bore-hole ground loops can be considered as being very robust components with a long service life, provided they are designed and installed according to accepted professional standards.

  7. Micro Hole Machining Experimental Study of Ultrasonic Elliptical Vibration Boring%微孔椭圆超声镗削加工实验研究

    Institute of Scientific and Technical Information of China (English)

    马协力; 张德远; 王冠

    2014-01-01

    Ultrasonic elliptical vibration micro-hole boring method is successfully applied to precision cutting due to its superior performances, such as low average cutting force and high machining precision. The theory of micro-hole boring machining and ultrasonic elliptical vibration micro-hole boring is analyzed to give fully play to the advantage of ultrasonic elliptical vibration for the problem of aviation engine fuel nozzles micro fabrication. The vibration amplitude contrast experiment proves that the ultrasonic vibration micro hole boring method has the advantages of low average cutting force and high surface quality compared with the traditional micro boring method. The micro hole ultrasonic elliptical boring is an effective method for micro hole machining.%微孔镗削加工采用椭圆超声技术具有降低切削力和改善表面加工质量的优势。为了充分发挥椭圆超声技术的优势,针对航空发动机燃油喷嘴精细加工的难题,分析了微孔镗削微细加工和微孔椭圆超声镗削的加工机理,通过振动振幅对比实验验证了微孔椭圆超声镗削加工比普通镗削加工更具有降低切削力和提高表面加工质量的能力。微孔椭圆超声振动加工为发动机燃油喷嘴的精细加工提供了一条有效途径。

  8. The Nolans Bore rare-earth element-phosphorus-uranium mineral system: geology, origin and post-depositional modifications

    Science.gov (United States)

    Huston, David L.; Maas, Roland; Cross, Andrew; Hussey, Kelvin J.; Mernagh, Terrence P.; Fraser, Geoff; Champion, David C.

    2016-08-01

    Nolans Bore is a rare-earth element (REE)-U-P fluorapatite vein deposit hosted mostly by the ~1805 Ma Boothby Orthogneiss in the Aileron Province, Northern Territory, Australia. The fluorapatite veins are complex, with two stages: (1) massive to granular fluorapatite with inclusions of REE silicates, phosphates and (fluoro)carbonates, and (2) calcite-allanite with accessory REE-bearing phosphate and (fluoro)carbonate minerals that vein and brecciate the earlier stage. The veins are locally accompanied by narrow skarn-like (garnet-diopside-amphibole) wall rock alteration zones. SHRIMP Th-Pb analyses of allanite yielded an age of 1525 ± 18 Ma, interpreted as the minimum age of mineralisation. The maximum age is provided by a ~1550 Ma SHRIMP U-Pb age for a pegmatite that predates the fluorapatite veins. Other isotopic systems yielded ages from ~1443 to ~345 Ma, implying significant post-depositional isotopic disturbance. Calculation of initial ɛNd and 87Sr/86Sr at 1525 Ma and stable isotope data are consistent with an enriched mantle or lower crust source, although post-depositional disturbance is likely. Processes leading to formation of Nolans Bore began with north-dipping subduction along the south margin of the Aileron Province at 1820-1750 Ma, producing a metasomatised, volatile-rich, lithospheric mantle wedge. About 200 million years later, near the end of the Chewings Orogeny, this reservoir and/or the lower crust sourced alkaline low-degree partial melts which passed into the mid- and upper-crust. Fluids derived from these melts, which may have included phosphatic melts, eventually deposited the Nolans Bore fluorapatite veins due to fluid-rock interaction, cooling, depressurisation and/or fluid mixing. Owing to its size and high concentration of Th (2500 ppm), in situ radiogenic heating caused significant recrystallisation and isotopic resetting. The system finally cooled below 300 °C at ~370 Ma, possibly in response to unroofing during the Alice Springs

  9. Test with different stress measurement methods in two orthogonal bore holes in Aespoe HRL

    Energy Technology Data Exchange (ETDEWEB)

    Janson, Thomas; Stigsson, Martin [Golder Associates AB, Stockholm (Sweden)

    2002-12-01

    conclusions have been drawn, based on the stress measurements and deeper investigations: The following stress state is obtained at the target volume at about -455 m. The minimum horizontal stress is between 10 and 13 MPa, which is lower than the theoretical vertical stress. The maximum horizontal stress is 24 {+-}5 MPa, most likely within the upper range. The vertical stress is between 15 and 20 MPa, most probably is this value only local due to the presence of a nearby fracture. The local disturbance of the stress field in the rock mass, due to discontinuities has been demonstrated. This also indicates one of the problems with stress measurements in boreholes. In the area with significant anisotropic stress conditions all the tested methods were able to determine the orientation of the principal major horizontal stress within {+-} 10 deg. The microscopy investigations confirm two sets of microcracks in the overcored core. One set was parallel and near the bore hole bottom and one set was perpendicular to the bottom and located a bit away from the hole bottom. The results from the overcoring may be influenced by microcracks, causing additional non-elastic strains. Only the results from the DDGS seem to have been influenced, indicating that the hollow cylinder of a 3D stress cell may be less sensitive for stress induced sample disturbance than core samples from the 2D Door stopper cell. The determination of Young's modulus in a medium grained crystalline rock with heterogeneity may not be trivial using core samples. The results from the determination influence the calculated stresses. Hydraulic fracturing most likely measures the most correct value of the minimum horizontal stress, provided that the induced fracture is aligned with the borehole. If the rock behaves reasonable elastic the overcoring methods provide stress magnitudes with an uncertainty of 15-20%. It seems likely that the overcoring methods may overestimate the stress magnitudes at large depth, due to the

  10. Ground-coupled bore-hole heat exchanger installation: new building in Wattwil; EWS-Anlage, Neubau CAS, Wattwil. Erdwaermesondenanlage

    Energy Technology Data Exchange (ETDEWEB)

    Eichenberger, R.; Kapp, Ch.

    2002-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a monitoring programme carried out on the bore-hole heat exchangers of a geothermal energy system used in a newly constructed commercial building in Wattwil, Switzerland. The geothermal installation is described, which uses two different types of geothermal probes, a normal duplex exchanger and the so-called umbrella probe. The results of the measurement campaigns that were carried out over two winter periods are presented, and the performance of the two types of heat-exchanger are compared. Using correlation diagrams, the two main factors influencing the performance of the probes - temperature and flow - are calculated. The report describes the monitoring configurations used and presents detailed results of the measurements made.

  11. A sparsely encrusted hardground with abundant Trypanites borings from the Llandovery of the Velise River, western Estonia (Baltica

    Directory of Open Access Journals (Sweden)

    Olev Vinn

    2016-02-01

    Full Text Available The Päärdu hardground from the Telychian (Rumba Formation of western Estonia is sparsely encrusted (0.4% of the studied surface by possible tabulate corals, sheet-like bryozoans and discoidal echinoderm holdfasts. Both the upper and cryptic sides of the hardground are intensely bioeroded by Trypanites borings. The taxonomic composition of the Päärdu hardground association is rather different from the characteristic Silurian association in being dominated by tabulate corals, while bryozoans and echinoderms played a minor role in the association. The Päärdu hardground is more sparsely encrusted than common for the Late Ordovician and Silurian hardgrounds, but this may be a characteristic feature of the hardgrounds of Baltica. The Päärdu hardground is important among the Silurian hardgrounds because it has unusually low encrustation combined with high bioerosion.

  12. CFD SIMULATION OF 3D FLOW IN LARGE-BORE AXIAL-FLOW PUMP WITH HALF-ELBOW SUCTION SUMP

    Institute of Scientific and Technical Information of China (English)

    WANG Fu-jun; LI Yao-jun; CONG Guo-hui; WANG Wen-e; WANG Hai-song

    2006-01-01

    Numerical simulations of 3D turbulent flow in a large-bore axial-flow pump coupled with half-elbow suction sump were performed by using CFD approach. The numerical model and velocity and pressure distributions in entire flow passage were presented. The obvious backflow in half-elbow suction sump and strong flow nonuniformity at suction sump outlet were observed, whereas these phenomena were not observed in existing studies performed for a separate suction sump by either experimental or numerical approach. This result indicates that the interaction between half-elbow suction sump and impeller has significant effect on the flow distribution in the pump passage. The change of pump efficiency caused by the interaction was discussed.

  13. 40Ar/39Ar geochronology, paleomagnetism, and evolution of the Boring volcanic field, Oregon and Washington, USA

    Science.gov (United States)

    Fleck, Robert J.; Hagstrum, Jonathan T.; Calvert, Andrew T.; Evarts, Russell C.; Conrey, Richard M.

    2014-01-01

    The 40Ar/39Ar investigations of a large suite of fine-grained basaltic rocks of the Boring volcanic field (BVF), Oregon and Washington (USA), yielded two primary results. (1) Using age control from paleomagnetic polarity, stratigraphy, and available plateau ages, 40Ar/39Ar recoil model ages are defined that provide reliable age results in the absence of an age plateau, even in cases of significant Ar redistribution. (2) Grouping of eruptive ages either by period of activity or by composition defines a broadly northward progression of BVF volcanism during latest Pliocene and Pleistocene time that reflects rates consistent with regional plate movements. Based on the frequency distribution of measured ages, periods of greatest volcanic activity within the BVF occurred 2.7–2.2 Ma, 1.7–0.5 Ma, and 350–50 ka. Grouped by eruptive episode, geographic distributions of samples define a series of northeast-southwest–trending strips whose centers migrate from south-southeast to north-northwest at an average rate of 9.3 ± 1.6 mm/yr. Volcanic activity in the western part of the BVF migrated more rapidly than that to the east, causing trends of eruptive episodes to progress in an irregular, clockwise sense. The K2O and CaO values of dated samples exhibit well-defined temporal trends, decreasing and increasing, respectively, with age of eruption. Divided into two groups by K2O, the centers of these two distributions define a northward migration rate similar to that determined from eruptive age groups. This age and compositional migration rate of Boring volcanism is similar to the clockwise rotation rate of the Oregon Coast Range with respect to North America, and might reflect localized extension on the trailing edge of that rotating crustal block.

  14. Direction of interaction between mountain pine beetle (Dendroctonus ponderosae) and resource-sharing wood-boring beetles depends on plant parasite infection.

    Science.gov (United States)

    Klutsch, Jennifer G; Najar, Ahmed; Cale, Jonathan A; Erbilgin, Nadir

    2016-09-01

    Plant pathogens can have cascading consequences on insect herbivores, though whether they alter competition among resource-sharing insect herbivores is unknown. We experimentally tested whether the infection of a plant pathogen, the parasitic plant dwarf mistletoe (Arceuthobium americanum), on jack pine (Pinus banksiana) altered the competitive interactions among two groups of beetles sharing the same resources: wood-boring beetles (Coleoptera: Cerambycidae) and the invasive mountain pine beetle (Dendroctonus ponderosae) (Coleoptera: Curculionidae). We were particularly interested in identifying potential mechanisms governing the direction of interactions (from competition to facilitation) between the two beetle groups. At the lowest and highest disease severity, wood-boring beetles increased their consumption rate relative to feeding levels at moderate severity. The performance (brood production and feeding) of mountain pine beetle was negatively associated with wood-boring beetle feeding and disease severity when they were reared separately. However, when both wood-boring beetles and high severity of plant pathogen infection occurred together, mountain pine beetle escaped from competition and improved its performance (increased brood production and feeding). Species-specific responses to changes in tree defense compounds and quality of resources (available phloem) were likely mechanisms driving this change of interactions between the two beetle groups. This is the first study demonstrating that a parasitic plant can be an important force in mediating competition among resource-sharing subcortical insect herbivores.

  15. Exploration on artificial bored pile construction quality control methods%人工挖孔桩施工质量控制方法探讨

    Institute of Scientific and Technical Information of China (English)

    何文斌

    2015-01-01

    The thesis describes merits and defects of artificial bored pile,and illustrates artificial bored pile construction technology procedures. Starting from three aspects of construction organization design compilation,construction scheme technology discloser and construction examination system compilation,it introduces artificial bored pile construction quality control measures,and puts forward corresponding processing counter-measures to existing construction problems,so as to guarantee artificial bored pile construction quality.%简述了人工挖孔灌注桩的优缺点,概括了人工挖孔桩施工的工艺流程,从施工组织设计的编制、施工方案的技术交底、施工检查制度的制定三方面,介绍了人工挖孔桩施工的质量控制措施,并针对施工中存在的问题,提出了相应的处理对策,确保了人工挖孔桩的施工质量。

  16. Study on saltwater intrusion in Qiantang estuary affected by tidal bore%涌潮对钱塘江河口盐水入侵影响研究

    Institute of Scientific and Technical Information of China (English)

    潘存鸿; 张舒羽; 史英标; 鲁海燕; 谢东风

    2014-01-01

    钱塘江河口潮强流急,涌潮汹涌,是典型的强混合型河口,其盐水入侵程度远强于其它潮汐河口。基于Godunov格式的有限体积法建立了涌潮作用下二维高精度盐水入侵数学模型,结合实测潮汐、涌潮和氯度资料分析,研究了涌潮对钱塘江河口盐水入侵的影响。结果表明,涌潮促使盐水入侵加剧,导致时间上和纵向上氯度变率增大,涌潮是形成盐度锋的动力机制。同时,涌潮紊动激烈,促使氯度垂向分布均匀。另外,还对氯度控制方程中扩散系数的取值进行了讨论,认为钱塘江河口扩散系数取102 m2/s量级较为合适。%With strong tide, rapid flow and turbulent tidal bore, Qiantang Estuary is a typical well-mixed one. Its saltwater intrusion is far stronger than other tidal estuaries. Based on a finite volume method with Godunov scheme, a 2D saltwater intrusion mathematical model affected by tidal bore was established. Com⁃bining with the field data analysis for tide,tidal bore and chlorinity,the effect of the tidal bore on saltwa⁃ter intrusion of Qiantang Estuary was studied. The tidal bore increases the aggravation of saltwater intru⁃sion,resulting in intensification of the gradient in time domain and in lengthways. The tidal bore is the ki⁃netic mechanism to form salinity front. Meanwhile,the fierce and turbulent tidal bore makes chlorinity even in vertical distribution. In addition, the value of chloride diffusion coefficient in the chlorinity control equa⁃tion has been discussed, and it is appropriate to take the diffusion coefficient in Qiantang Estuary for 102 m2/s magnitude.

  17. Characterization of the excavation disturbance caused by boring of the experimental full scale deposition holes in the Research Tunnel of Olkiluoto

    Energy Technology Data Exchange (ETDEWEB)

    Autio, J. [Saanio and Riekkola Oy, Helsinki (Finland)

    1997-09-01

    Three holes, the size of deposition holes, were bored in the Research Tunnel using a novel full-face boring technique. During the boring test, procedures were carried out in order to determine the effect of changes in operating parameters on the performance of the boring machine and the quality of the hole. Evaluation of the quality of the hole included studies of the geometry of the holes, measurements of surface roughness using a laser profilometer, rock mechanical determinations and study of excavation disturbances in the zone adjacent to the surface of the holes using two novel methods, the He-gas method and the {sup 14}C-polymethylmethacrylate ({sup 14}C-PMMA) method. It was found that there is a distinct disturbed zone adjacent to the surface of the full scale deposition holes which can be divided into three different zones. The zones are as follows: a crushed zone penetrating to a depth of about 3 mm from the surface, a fractured zone extending to a depth of 6 - 10 mm from the crushed zone and a micro fractured zone extending to a depth of 15 - 31 mm from the fractured zone. The porosity of the rock in the disturbed zone measured using the {sup 14}C-PMMA method was clearly greater than the porosity of undisturbed rock to a depth of about 11 mm. The values of permeability and effective diffusion coefficient in the disturbed zone measured in a direction perpendicular to the disturbed surface were found to be approximately one order of magnitude larger than those of undisturbed rock. The degree of disturbance was found to be greater where higher levels of thrust had been employed during the boring process. The results obtained also suggest that the disturbance caused by using 4- and 5-row cutters in the cutter head is more pronounced than the disturbance caused when using 5- and 6-row cutters 31 refs, 118 figs, 15 tabs

  18. Observations of large-amplitude cross-shore internal bores near the shelf break, Santa Monica Bay, CA

    Science.gov (United States)

    Noble, M.A.; Xu, J. P.

    2003-01-01

    Two sets of moorings were deployed along a cross-shelf transect in central Santa Monica bay for four months in the winter of 1998-1999. Both sites had an array of instruments attached to tripods set on the seafloor to monitor currents over the entire water column, surface waves, near-bed temperature, water clarity and suspended sediment. A companion mooring had temperature sensors spaced approximately 10 m apart to measure temperature profiles between the surface and the seafloor. One array was deployed in 70 m of water at a site adjacent to the shelf break, just northwest of a major ocean outfall. The other was deployed on the mid shelf in 35 m of water approximately 6 km from the shelf break site. The subtidal currents in the region flowed parallel to the isobaths with fluctuating time scales around 10 days, a typical coastal-ocean pattern. However, during the falling phase of the barotropic spring tide, sets of large-amplitude, sheared cross-shore current pulses with a duration of 2-5 h were observed at the shelf break site. Currents in these pulses flowed exclusively offshore in a thin layer near the bed with amplitudes reaching 30-40 cm/s. Simultaneously, currents with amplitudes around 15-20 cm/s flowed exclusively onshore in the thicker layer between the offshore flow layer and the sea surface. The net offshore transport was about half the onshore transport. Near-surface isotherms were depressed 30-40 m. These pulses were likely internal bores generated by tidal currents. Bed stresses associated with these events exceeded 3 dynes/cm2. These amplitudes are large enough to resuspend and transport not only fine-grained material, but also medium to coarse sands from the shelf toward the slope. Consequently, the seafloor over the shelf break was swept clear of fine sediments. The data suggest that the internal bores dissipate and are reduced in amplitude as they propagate across this relatively narrow shelf. There is evidence that they reach the 35 m site, but

  19. Design and Manufacture of a Large-Bore 10 T Superconducting Dipole for the CERN Cable Test Facility

    CERN Document Server

    Leroy, D; Verweij, A P; Boschmann, H; Dubbeldam, R L; González-Pelayo, J

    2000-01-01

    A large-bore 10 T superconducting dipole magnet was designed and fabricated in close cooperation between CERN and HMA Power Systems. The dipole has a length of about 1.7 m and an aperture of 88 mm and is composed of two two-layer poles wound with NbTi cables cooled to 1.9 K to reach magnetic inductions close to 10 T. This dipole will be installed at the CERN cable test facility and used as a background field magnet to test LHC superconducting cables. In its large aperture up to four cable samples can be tested at the same time. The mechanical design of the magnet is such that coil prestress variations between warm and cold conditions are kept within 20 MPa. A short model was also built and cooled down in order to check and confirm with test results the mechanical behavior of the dipole. Magnetic measurements, at room temperature, were performed upon its arrival at CERN prior to installation in the test facility. The dipole was recently cooled down and tested. This paper will discuss the design, the main manu...

  20. Free-face-Assisted Rock Breaking Method Based on the Multi-stage Tunnel Boring Machine (TBM) Cutterhead

    Science.gov (United States)

    Geng, Qi; Wei, Zhengying; Meng, Hao; Macias, Francisco Javier; Bruland, Amund

    2016-11-01

    In order to improve the rock breaking efficiency of hard rock tunnel boring, many innovative rock breaking methods have been proposed (e.g., the water jet cutting, the high-power laser cutting, the impact-rotary drilling, and the undercutting method). However, most of the methods are not applicable to TBMs due to some structural reasons. Aiming on this problem, a free-face-assisted rock breaking method based on the multi-stage TBM cutterhead has been proposed. Series of proof-of-concept tests includes (1) the static compression test with vertical free face and (2) the rotary cutting tests in different free surface conditions were designed and carried out. The results show that the rock breaking force and efficiency can be significantly reduced and improved, respectively, with the assistance of the free face, due to the failure of the rock close to the free face is tensile-dominated failure. The influencing distance of the free face in the radial direction is at least 330 mm which covers about 5 disk cutters. Finally, the general structure of a small two-stage cutterhead (4 m in diameter) was tentatively designed in order to provide a possible approach to apply the free-face effect to TBMs.

  1. Performance characteristics of tunnel boring machine in basalt and pyroclastic rocks of Deccan traps – A case study

    Directory of Open Access Journals (Sweden)

    Prasnna Jain

    2014-02-01

    Full Text Available A 12.24 km long tunnel between Maroshi and Ruparel College is being excavated by tunnel boring machine (TBM to improve the water supply system of Greater Mumbai, India. In this paper, attempt has been made to establish the relationship between various litho-units of Deccan traps, stability of tunnel and TBM performances during the construction of 5.83 km long tunnel between Maroshi and Vakola. The Maroshi–Vakola tunnel passes under the Mumbai Airport and crosses both runways with an overburden cover of around 70 m. The tunneling work was carried out without disturbance to the ground. The rock types encountered during excavation are fine compacted basalt, porphyritic basalt, amygdaloidal basalt, pyroclastic rocks with layers of red boles and intertrappean beds consisting of various types of shales. Relations between rock mass properties, physico-mechanical properties, TBM specifications and the corresponding TBM performance were established. A number of support systems installed in the tunnel during excavation were also discussed. The aim of this paper is to establish, with appropriate accuracy, the nature of subsurface rock mass condition and to study how it will react to or behave during underground excavation by TBM. The experiences gained from this project will increase the ability to cope with unexpected ground conditions during tunneling using TBM.

  2. A comparison of 1D and 1.5D arrays for imaging volumetric flaws in small bore pipework

    Science.gov (United States)

    Barber, T. S.; Wilcox, P. D.; Nixon, A. D.

    2015-03-01

    1.5D arrays can be seen as a potentially ideal compromise between 1D arrays and 2D matrix arrays in terms of focusing capability, element density, weld coverage and data processing time. This paper presents an initial study of 1D and 1.5D arrays for high frequency (15MHz) imaging of volumetric flaws in small-bore (30-60mm outer diameter) thin-walled (3-8mm) pipework. A combination of 3D modelling and experimental work is used to determine Signal to Noise Ratio (SNR) improvement with a strong relationship between SNR and the longer dimension of element size observed. Similar behavior is demonstrated experimentally rendering a 1mm diameter Flat Bottom Hole (FBH) in Copper-Nickel alloy undetectable using a larger array element. A 3-5dB SNR increase is predicted when using a 1.5D array assuming a spherical reflector and a 2dB increase was observed on experimental trials with a FBH. It is argued that this improvement is likely to be a lower bound estimate due to the specular behavior of a FBH with future trials planned on welded samples with realistic flaws.

  3. Surface-Treated versus Untreated Large-Bore Catheters as Vascular Access in Hemodialysis and Apheresis Treatments

    Directory of Open Access Journals (Sweden)

    Rolf Bambauer

    2012-01-01

    Full Text Available Background. Catheter-related infections, thrombosis, and stenosis are among the most frequent complications associated with catheters, which are inserted in vessels. Surface treatment processes of the outer surface, such as ion-beam-assisted deposition, can be used to mitigate such complications. Methods. This retrospective study (1992–2007 evaluated silver-coated (54 patients and noncoated (105 patients implanted large-bore catheters used for extracorporeal detoxification. The catheters were inserted into the internal jugular or subclavian veins. After removal, the catheters were cultured for bacterial colonization using standard microbiologic assays. They also were examined using scanning electron microscope. Results. The silver coated catheters showed a tendency towards longer in situ time. The microbiologic examinations of the catheter tips were in both catheter types high positive, but not significant. Conclusion. The silver-coated catheters showed no significantly reduction in infection rate by evaluation of all collected data in this retrospective study. There was no association between both catheters in significantly reducing savings in treatment costs and in reducing patient discomfort. Other new developed catheter materials such as the microdomain-structured inner and outer surface are considered more biocompatible because they mimic the structure of natural biological surface.

  4. Selected Abiotic and Biotic Environmental Stress Factors Affecting Two Economically Important Sugarcane Stalk Boring Pests in the United States

    Directory of Open Access Journals (Sweden)

    Allan T. Showler

    2016-02-01

    Full Text Available Sugarcane, Saccharum spp., in the United States is attacked by a number of different arthropod pests. The most serious among those pests are two stalk boring moths in the Family Crambidae: the sugarcane borer, Diatraea saccharalis (F., and the Mexican rice borer, Eoreuma loftini (Dyar. The two species are affected by abiotic and biotic environmental stress factors. Water deficit and excessive soil nitrogen alter physical and physiochemical aspects of the sugarcane plant that make the crop increasingly vulnerable to E. loftini. Weed growth can be competitive with sugarcane but it also supports enhanced abundances and diversity of natural enemies that can suppress infestations of D. saccharalis. In an instance where the stalk borer is considered a stress factor, proximity of vulnerable crops to sugarcane can influence levels of E. loftini infestation of sugarcane. The adverse effects of each stress factor, in terms of stalk borer attack, can be reduced by adopting appropriate cultural practices, such as adequate irrigation, judicious use of nitrogen fertilizer, using noncompetitive weed growth, and not planting vulnerable crops near sugarcane fields. Understanding the relationships between stress factors and crop pests can provide valuable insights for plant breeders and tools for incorporation into integrated pest management strategies.

  5. The characteristics and construction technology of rotary digging bored piles%旋挖钻孔灌注桩特性及施工工艺

    Institute of Scientific and Technical Information of China (English)

    王成全

    2015-01-01

    论述了旋挖钻孔灌注桩的技术特性,从土层性质、运行成本、工程量等方面,分析了旋挖桩在工程应用中的局限性,并以湿作业旋挖成孔为例,介绍了旋挖钻孔灌注桩的施工工艺,为类似工程施工积累了经验。%This paper discussed the technology characteristics of rotary digging bored piles,from the soil properties,operation cost,volume and other aspects,analyzed the limitations of rotary digging pile in engineering application,and taking the wet homework rotary digging pore forming for example,introduced the construction technology of rotary digging bored piles,accumulated experience for similar engineering construction.

  6. SU-E-I-20: Comprehensive Quality Assurance Test of Second Generation Toshiba Aquilion Large Bore CT Simulator Based On AAPM TG-66 Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D [Toshiba America Medical Systems, Tustin, CA (United States)

    2015-06-15

    Purpose: AAPM radiation therapy committee task group No. 66 (TG-66) published a report which described a general approach to CT simulator QA. The report outlines the testing procedures and specifications for the evaluation of patient dose, radiation safety, electromechanical components, and image quality for a CT simulator. The purpose of this study is to thoroughly evaluate the performance of a second generation Toshiba Aquilion Large Bore CT simulator with 90 cm bore size (Toshiba, Nasu, JP) based on the TG-66 criteria. The testing procedures and results from this study provide baselines for a routine QA program. Methods: Different measurements and analysis were performed including CTDIvol measurements, alignment and orientation of gantry lasers, orientation of the tabletop with respect to the imaging plane, table movement and indexing accuracy, Scanogram location accuracy, high contrast spatial resolution, low contrast resolution, field uniformity, CT number accuracy, mA linearity and mA reproducibility using a number of different phantoms and measuring devices, such as CTDI phantom, ACR image quality phantom, TG-66 laser QA phantom, pencil ion chamber (Fluke Victoreen) and electrometer (RTI Solidose 400). Results: The CTDI measurements were within 20% of the console displayed values. The alignment and orientation for both gantry laser and tabletop, as well as the table movement and indexing and scanogram location accuracy were within 2mm as specified in TG66. The spatial resolution, low contrast resolution, field uniformity and CT number accuracy were all within ACR’s recommended limits. The mA linearity and reproducibility were both well below the TG66 threshold. Conclusion: The 90 cm bore size second generation Toshiba Aquilion Large Bore CT simulator that comes with 70 cm true FOV can consistently meet various clinical needs. The results demonstrated that this simulator complies with the TG-66 protocol in all aspects including electromechanical component

  7. Finite Element Analysis and Research of Boring Bar Based on ANSYS%基于ANSYS的镗刀杆有限元分析研究

    Institute of Scientific and Technical Information of China (English)

    孙伏

    2015-01-01

    By taking boring bar with L/D=10 as the research object, boring bar’s statics analysis and modal analysis are carried out with cutting condition variation including cutting speed, feeding and back cutting depth by single factor analysis, with finite element analysis with the help of ANSYS software. Obtain maximum deformation and maximum stress on boring bar and change rule. Modal analysis of preceding 10 orders vibration is carried out to obtain modal frequency and vibration patterns. The major factor influencing quality is summarized. The selection of cutting condition and boring bar structure design method are researched.%以L/D=10的镗刀杆为研究对象,采用有限元分析方法,借助ANSYS软件工具,用单因素分析法,进行了加工中切削用量的三要素即切削速度、进给量、背吃刀量变化时细长刀杆的静力学分析和模态分析,分析了刀杆的最大变形量和最大应力与各因素间的变化规律;进行了夹紧状态下镗刀杆的前10阶模态分析,得到模态频率和振型。总结了其中影响加工质量的主要因素和切削用量选择时应注意的问题,对切削参数的选择和刀杆的结构设计方法进行了研究。

  8. 内置式减振镗杆温升的分析与研究%Research on the Temperature Rise of Built-in Damping Boring Bar

    Institute of Scientific and Technical Information of China (English)

    肖平; 冯烨; 曾海波

    2011-01-01

    In the deep hole cutting process chatter of boring bar seriously affects the quality of hole.However, suppression of vibration has very big relations with working temperature of boring bar. This article mainly studied on the performance of vibration isolation after temperature rise in work. Based on the structural design and simplified three-dimensional model of boring bar, according to the first law of thermodynamics, heat generated by the vibration of built-in shock absorber could be analyzed. On the side steady heat analysis and transient thermal analysis of boring bars was analyzed by use of finite element analysis software ANSYS Workbench, finally it concluded the results of vibration absorption and temperature changes of damping liquid.%深孔加工中镗杆的颤振严重影响孔的加工质量,而振动的抑制与镗杆的内部工作温度有很大关系.文章主要研究镗杆在工作中,温度升高以后对镗杆减振性能的影响.通过对镗杆的结构设计和三维模型的简化,根据热力学第一定律,对镗杆内置减振器振动产生的热量进行分析,运用有限元分析软件ANSYS Workbench,对镗杆进行稳态热分析和瞬态热分析,最后得出镗杆减振效果和阻尼液的温度变化情况.

  9. A new species and new records of parasitic wasps (Hymenoptera: Pteromalidae of wood boring beetles from southern Western Ghats, Kerala, India

    Directory of Open Access Journals (Sweden)

    P.M. Sureshan

    2013-07-01

    Full Text Available A new species of Pteromalidae (Hymenoptera: Chalcidoidea parasitising wood boring beetles, Cleonymus kamijoi, and two species of Pteromalidae, Trigonoderus pulcher Walker and male of Heydenia tuberculata Sureshan are reported for the first time from the southern Western Ghats, Kerala. The genus Trigonoderus Westwood is reported for the first time from India and the male of Heydenia tuberculata Sureshan is reported and described for the first time.

  10. Identification of wood-boring beetles (Cerambycidae and Buprestidae) intercepted in trade-associated solid wood packaging material using DNA barcoding and morphology.

    Science.gov (United States)

    Wu, Yunke; Trepanowski, Nevada F; Molongoski, John J; Reagel, Peter F; Lingafelter, Steven W; Nadel, Hannah; Myers, Scott W; Ray, Ann M

    2017-01-16

    Global trade facilitates the inadvertent movement of insect pests and subsequent establishment of populations outside their native ranges. Despite phytosanitary measures, nonnative insects arrive at United States (U.S.) ports of entry as larvae in solid wood packaging material (SWPM). Identification of wood-boring larval insects is important for pest risk analysis and management, but is difficult beyond family level due to highly conserved morphology. Therefore, we integrated DNA barcoding and rearing of larvae to identify wood-boring insects in SWPM. From 2012 to 2015, we obtained larvae of 338 longhorned beetles (Cerambycidae) and 38 metallic wood boring beetles (Buprestidae) intercepted in SWPM associated with imported products at six U.S. ports. We identified 265 specimens to species or genus using DNA barcodes. Ninety-three larvae were reared to adults and identified morphologically. No conflict was found between the two approaches, which together identified 275 cerambycids (23 genera) and 16 buprestids (4 genera). Our integrated approach confirmed novel DNA barcodes for seven species (10 specimens) of woodborers not in public databases. This study demonstrates the utility of DNA barcoding as a tool for regulatory agencies. We provide important documentation of potential beetle pests that may cross country borders through the SWPM pathway.

  11. Identification of wood-boring beetles (Cerambycidae and Buprestidae) intercepted in trade-associated solid wood packaging material using DNA barcoding and morphology

    Science.gov (United States)

    Wu, Yunke; Trepanowski, Nevada F.; Molongoski, John J.; Reagel, Peter F.; Lingafelter, Steven W.; Nadel, Hannah; Myers, Scott W.; Ray, Ann M.

    2017-01-01

    Global trade facilitates the inadvertent movement of insect pests and subsequent establishment of populations outside their native ranges. Despite phytosanitary measures, nonnative insects arrive at United States (U.S.) ports of entry as larvae in solid wood packaging material (SWPM). Identification of wood-boring larval insects is important for pest risk analysis and management, but is difficult beyond family level due to highly conserved morphology. Therefore, we integrated DNA barcoding and rearing of larvae to identify wood-boring insects in SWPM. From 2012 to 2015, we obtained larvae of 338 longhorned beetles (Cerambycidae) and 38 metallic wood boring beetles (Buprestidae) intercepted in SWPM associated with imported products at six U.S. ports. We identified 265 specimens to species or genus using DNA barcodes. Ninety-three larvae were reared to adults and identified morphologically. No conflict was found between the two approaches, which together identified 275 cerambycids (23 genera) and 16 buprestids (4 genera). Our integrated approach confirmed novel DNA barcodes for seven species (10 specimens) of woodborers not in public databases. This study demonstrates the utility of DNA barcoding as a tool for regulatory agencies. We provide important documentation of potential beetle pests that may cross country borders through the SWPM pathway. PMID:28091577

  12. Construction Principle and Art of Single Bore Multiple Anchor Method%单孔复合锚固法施工原理和工艺

    Institute of Scientific and Technical Information of China (English)

    张权

    2012-01-01

      结合现场施工简要的阐述单孔复合锚固法的基本原理和施工工艺。与传统锚固法相比,单孔复合锚能将荷载分散地传递给钻孔内几个较短的固定段,能有效地调用天然地层强度,显著提高锚杆承载力,从而取得良好的经济效益。%  In connection with the on-site construction, this paper simply introduces the basic principle and construction theory of single bore multiple anchor method. Compared with the traditional anchor method, the single bore multiple anchor method can dispersedly transfer the capacity to the short fixing segments in bores, effectively invoke natural stratum strength, and significantly improve the bearing capacity of anchor rod, so as to achieve a nice economic benefit.

  13. 挖孔桩混凝土异常硬化原因分析研究%Analysis on Reasons of Abnormal Hardening of Concrete in Bored Pile

    Institute of Scientific and Technical Information of China (English)

    石从黎; 杨翔; 宋开伟

    2011-01-01

    针对重庆某工程挖孔桩混凝土异常硬化问题,采用物理试验、化学分析、X衍射分析和热分析等手段对异常硬化混凝土的物理性质、化学成分和矿物成分进行分析.结果表明:挖孔桩内混凝土含水率极高,强度低,但有明显的水泥水化产物存在;混凝土异常硬化的主要原因是挖孔桩内有渗水或积水造成混凝土严重离析分层,水化产物不能填满空隙,固体颗粒搭接少,导致混凝土疏松.%According to the problem about abnormal hardening of bored pile concrete in a project in Cbongqing, the authors analyze physical properties, chemical composition and mineral composition of abnormal hardening conerete by physical examination, chemical analysis, X-ray diffraction and thermal analysis. The results show that bored pile concrete has high water content, low strength and obvious cement hydration produets, The reason on abnormal hardening of concrete is that because of serious segregation of concrete caused by seepage and water accumulation in bored pile, cement hydration produets can't fill void.

  14. Heavy metal contamination in bore water due to industrial pollution and polluted and non polluted sea water intrusion in Thoothukudi and Tirunelveli of South Tamil Nadu, India.

    Science.gov (United States)

    Puthiyasekar, C; Neelakantan, M A; Poongothai, S

    2010-12-01

    This study investigates the pollution vulnerability of bore water in the coastal region of Tirunelveli and Thoothukudi in the state of Tamilnadu, India. There are no industries in the Tirunelveli Coastal area whereas there are many industries in SIPCOT (State Industries Promotion Corporation of Tamilnadu) Thoothukudi, and coastal area of Thoothukudi. Bore water from the SIPCOT, coastal area of Thoothukudi and Tirunelveli were collected periodically from July 2006 to May 2008 for this study. These samples were tested and analyzed to find the concentrations of sodium, magnesium, aluminium, potassium, calcium, copper, cadmium, mercury and lead. The toxic cadmium concentration was found in the range of 0.00-0.22 mg Kg⁻¹ at SIPCOT 2 in November 2007, mercury 0.00-0.024 mg Kg⁻¹ and lead 0.00-0.02 mg Kg⁻¹ in SIPCOT 2 in January 2008. The level of contamination is higher than the WHO limits of drinking water standards; but copper and aluminium content are within the limit. On the other hand, the samples taken from bores in Tirunelveli coastal area are non-polluted, and the analysis shows that all the metals are within the limits of WHO standard.

  15. Production of the heat exchanger tubes, which will cool down the LHC magnets, and of the cold bore tubes, in which the proton beams will circulate, is due to be completed around the end of 2004. These essential components of the LHC magnets are receiving their finishing touches at CERN : cold bore tubes

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Insulation of the cold bore tubes in which the LHC beams will circulate takes place in Building 927. In the background, Bruno Meunier checks the wrapping machine while, in the foreground, Olivier Vasseur removes the polyester wrapping that covers the tube's insulating layers.

  16. EBZ-220型掘进机回油冷却器的改造设计%Retrofit Design of Oil Return Cooler in EBZ-220 Tunnel-Boring Machines

    Institute of Scientific and Technical Information of China (English)

    闫品

    2015-01-01

    Through the transformation design of the cooler of EBZ-220 type tunnel-boring machines, the cooling effect of the tunnel-boring machines is greatly improved, the efficiency of boring machine is increased, the failure rate of the tunnel-boring machines is reduced, longer service life is obtained.%通过对EBZ-220型掘进机冷却器的改造设计,大大改善了掘进机的冷却效果,提高了掘进机的使用效率,降低了掘进机故障率,使其效率更高,寿命更长。

  17. Closed bore XMR (CBXMR) systems for aortic valve replacement: Active magnetic shielding of x-ray tubes

    Energy Technology Data Exchange (ETDEWEB)

    Bracken, John A.; DeCrescenzo, Giovanni; Komljenovic, Philip; Lillaney, Prasheel V.; Fahrig, Rebecca; Rowlands, J. A. [Department of Medical Biophysics and Sunnybrook Health Sciences Center, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Medical Biophysics and Sunnybrook Health Sciences Center, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada)

    2009-05-15

    Hybrid closed bore x-ray/MRI systems are being developed to improve the safety and efficacy of percutaneous aortic valve replacement procedures by harnessing the complementary strengths of the x-ray and MRI modalities in a single interventional suite without requiring patient transfer between two rooms. These systems are composed of an x-ray C-arm in close proximity ({approx_equal}1 m) to an MRI scanner. The MRI magnetic fringe field can cause the electron beam in the x-ray tube to deflect. The deflection causes the x-ray field of view to shift position on the detector receptacle. This could result in unnecessary radiation exposure to the patient and the staff in the cardiac catheterization laboratory. Therefore, the electron beam deflection must be corrected. The authors developed an active magnetic shielding system that can correct for electron beam deflection to within an accuracy of 5% without truncating the field of view or increasing exposure to the patient. This system was able to automatically adjust to different field strengths as the external magnetic field acting on the x-ray tube was changed. Although a small torque was observed on the shielding coils of the active shielding system when they were placed in a magnetic field, this torque will not impact their performance if they are securely mounted on the x-ray tube and the C-arm. The heating of the coils of the shielding system for use in the clinic caused by electric current was found to be slow enough not to require a dedicated cooling system for one percutaneous aortic valve replacement procedure. However, a cooling system will be required if multiple procedures are performed in one session.

  18. The complete genome of Teredinibacter turnerae T7901: an intracellular endosymbiont of marine wood-boring bivalves (shipworms.

    Directory of Open Access Journals (Sweden)

    Joyce C Yang

    Full Text Available Here we report the complete genome sequence of Teredinibacter turnerae T7901. T. turnerae is a marine gamma proteobacterium that occurs as an intracellular endosymbiont in the gills of wood-boring marine bivalves of the family Teredinidae (shipworms. This species is the sole cultivated member of an endosymbiotic consortium thought to provide the host with enzymes, including cellulases and nitrogenase, critical for digestion of wood and supplementation of the host's nitrogen-deficient diet. T. turnerae is closely related to the free-living marine polysaccharide degrading bacterium Saccharophagus degradans str. 2-40 and to as yet uncultivated endosymbionts with which it coexists in shipworm cells. Like S. degradans, the T. turnerae genome encodes a large number of enzymes predicted to be involved in complex polysaccharide degradation (>100. However, unlike S. degradans, which degrades a broad spectrum (>10 classes of complex plant, fungal and algal polysaccharides, T. turnerae primarily encodes enzymes associated with deconstruction of terrestrial woody plant material. Also unlike S. degradans and many other eubacteria, T. turnerae dedicates a large proportion of its genome to genes predicted to function in secondary metabolism. Despite its intracellular niche, the T. turnerae genome lacks many features associated with obligate intracellular existence (e.g. reduced genome size, reduced %G+C, loss of genes of core metabolism and displays evidence of adaptations common to free-living bacteria (e.g. defense against bacteriophage infection. These results suggest that T. turnerae is likely a facultative intracellular ensosymbiont whose niche presently includes, or recently included, free-living existence. As such, the T. turnerae genome provides insights into the range of genomic adaptations associated with intracellular endosymbiosis as well as enzymatic mechanisms relevant to the recycling of plant materials in marine environments and the production

  19. Evaluating safety of tunneled small bore central venous catheters in chronic kidney disease population: A quality improvement initiative.

    Science.gov (United States)

    Bhutani, Gauri; El Ters, Mireille; Kremers, Walter K; Klunder, Joe L; Taler, Sandra J; Williams, Amy W; Stockland, Andrew H; Hogan, Marie C

    2016-09-20

    Introduction Peripherally inserted central venous catheters (PICCs) may adversely impact future successful arteriovenous fistulae (AVF). As part of a quality improvement project, the performance of tunneled small bore tunneled central venous catheters (TSB-CVCs), as alternatives to PICCs, was evaluated. Methods A retrospective observational study, involving individuals ≥18 years of age who underwent TSB-CVC placement by Interventional Radiology at Mayo Clinic, Rochester, MN between 1/1/2010 and 8/30/2013. Findings The study cohort included 92 patients with a median age of 55 (46-67) years, who underwent 108 TSB-CVC placements. Baseline renal disease was present in 71% (77/108). Most TSB-CVCs were placed in hospitalized patients (94%; 102/108); five French in diameter (61%; 66/108) and located in an internal jugular vein (84%; 91/108). Median catheter indwelling time was 20 (11-43) days (n = 84). TSB-CVC-related bloodstream infection, deep venous thrombosis (DVT), and superficial venous thrombosis (SpVT) rates per line were 0.009 (1/108), 0.018 (2/108), and 0.009 (1/108), respectively. Venous outcomes in a subgroup of 54 patients, who had documented PICC placements (n = 161) in addition to TSB-CVC (n = 58) were compared. TSB-CVC-DVT rate was lower than the PICC-DVT rate (0.017 [1/58] vs. 0.106 per line [17/161]; P = 0.04). The TSB-CVC-SpVT rate was not different from the PICC-SpVT rate (0 [0/58] vs. 0.037 [6/161] per line; P = 0.14). Discussion TSB-CVCs demonstrated an excellent safety profile in our study. These catheters should be preferentially utilized for arm vein preservation in advanced kidney disease. Their impact on future AVF success needs further evaluation.

  20. Geometric accuracy in three-dimensional coordinates of Leksell stereotactic skull frame with wide-bore 1.5-T MRI compared with conventional 1.5-T MRI.

    Science.gov (United States)

    Nakazawa, Hisato; Komori, Masataka; Shibamoto, Yuta; Takikawa, Yukinori; Mori, Yoshimasa; Tsugawa, Takahiko

    2014-10-01

    The use of 1.5-tesla (T) magnetic resonance (MR) imaging with a wide and simultaneously short bore enhances patient comfort compared with traditional 1.5-T MR imaging and is becoming increasingly available in stereotactic radiosurgery treatment planning. However, the geometric accuracy seems unavoidably worse in wide-bore MR imaging than in conventional MR imaging. We assessed the geometric distortion of the stereotactic image attached on a Leksell skull frame in conventional and wide-bore 1.5-T MR imaging. Two kinds of acrylic phantoms were placed on the skull frame and were scanned using computed tomography (CT) and conventional and wide-bore 1.5-T MR imaging. The three-dimensional coordinates on both MR imaging were compared with those on CT. Deviations of measured coordinates at selected points (x = 50, 100, 150 mm; y = 50, 100, 150 mm) were indicated on different axial planes (z = 50, 75, 100, 125, 150 mm). The differences of coordinates were less than 1.0 mm in the entire treatable area for conventional MR imaging. With the large bore system, the differences of the coordinates were less than 1.0 mm around the center but substantially exceeded 1.0 mm in the peripheral regions. Further study is needed to increase the geometric accuracy of wide-bore MR imaging for stereotactic radiosurgery treatment planning.

  1. Use of a Tantalum Liner to Reduce Bore Erosion and Increase Muzzle Velocity in Two-Stage Light Gas Guns

    Science.gov (United States)

    Bogdanoff, David W.

    2015-01-01

    velocity and reduce bore erosion.

  2. Instrument contributions to resolution and sensitivity in ultra high performance liquid chromatography using small bore columns: comparison of diode array and triple quadrupole mass spectrometry detection.

    Science.gov (United States)

    Buckenmaier, Stephan; Miller, Christine A; van de Goor, Tom; Dittmann, Monika M

    2015-01-16

    UHPLC with DAD-UV detection or in combination with mass spectrometry (MS) has proven to be a robust and widely applicable platform for high sensitivity analyses of many types of chemical compounds. The majority of users employ narrow bore columns with 2.1mm internal diameter (ID) typically exhibiting very high efficiencies (>200,000 plates/m). This ultimately sets stringent demands upon the chromatographic system as the separation efficiency can be compromised by external contributions to dispersion caused by connection capillaries, auto-sampler and/or the detection device. Sample limited applications often use reduced column diameters down to capillary- or even nano-column format. Capillary (ID≤0.5mm) or small-bore columns (ID≤1mm) can be a good compromise between system robustness and enhanced sensitivity. Yet in this case, extra-column dispersion gains additional importance due to reduced peak volumes. To design an optimized system configuration for specific column dimensions and applications it is crucial to understand the dispersion contributions of individual extra-column components. This was subject to many studies done within our group and by others. Here, we employed a fully optimized UHPLC/UV system to investigate the contribution to peak dispersion obtained from columns ranging from capillary to narrow bore (0.3, 0.5, 1, 2.1mm) using a set of small molecules that were analyzed in gradient mode. Further UV detection was replaced by a triple quadrupole (QQQ) MS in order to evaluate its contribution to band broadening. In this context the impact of column-ID upon MS sensitivity when interfaced with an Agilent Jet Stream source was investigated. Data obtained from our test suite of compounds shows mostly mass-sensitive behavior of this advanced electrospray technology.

  3. MRI-Guided Intervention for Breast Lesions Using the Freehand Technique in a 3.0-T Closed-Bore MRI Scanner: Feasibility and Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hye Young [Department of Radiology, Gyeongsang National University Hospital, Jinju 660-702 (Korea, Republic of); Kim, Sun Mi; Jang, Mijung; Yun, Bo La [Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Kim, Sung-Won; Kang, Eunyoung [Department of Surgery, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Park, So Yeon [Department of Pathology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Moon, Woo Kyung [Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of); Ko, Eun Sook [Department of Radiology, Samsung Medical Center, Seoul 135-710 (Korea, Republic of)

    2013-07-01

    To report the feasibility of magnetic resonance imaging (MRI)-guided intervention for diagnosing suspicious breast lesions detectable by MRI only, using the freehand technique with a 3.0-T closed-bore MRI scanner. Five women with 5 consecutive MRI-only breast lesions underwent MRI-guided intervention: 3 underwent MRI-guided needle localization and 2, MRI-guided vacuum-assisted biopsy. The interventions were performed in a 3.0-T closed-bore MRI system using a dedicated phased-array breast coil with the patients in the prone position; the freehand technique was used. Technical success and histopathologic outcome were analyzed. MRI showed that four lesions were masses (mean size, 11.5 mm; range, 7-18 mm); and 1, a nonmass-like enhancement (maximum diameter, 21 mm). The locations of the lesions with respect to the breast with index cancer were as follows: different quadrant, same breast - 3 cases; same quadrant, same breast - 1 case; and contralateral breast - 1 case. Histopathologic evaluation of the lesions treated with needle localization disclosed perilobular hemangioma, fibrocystic change, and fibroadenomatous change. The lesions treated with vacuum-assisted biopsy demonstrated a radial scar and atypical apocrine hyperplasia. Follow-up MRI after 2-7 months (mean, 4.6 months) confirmed complete lesion removal in all cases. MRI-guided intervention for breast lesions using the freehand technique with a 3.0-T closed-bore MRI scanner is feasible and accurate for diagnosing MRI-only lesions.

  4. 1 MA Breech Upgrade for the U.S. Army Research Laboratory’s (ARL’s) Rectangular 22- x-44-mm In-bore Cross Section Railgun

    Science.gov (United States)

    2011-08-01

    60-μH or a 30-μH inductor, allowed the generation of output pulses of different profiles. Since 2001, the power supply, railgun and breech, has...A Spice-based Code for ARL’s 4.5-MJ Electromagnetic Launcher Pulsed Power Supply System; ARL-TR- 2592; U.S. Army Research Laboratory: Aberdeen...1 MA Breech Upgrade for the U.S. Army Research Laboratory’s (ARL’s) Rectangular 22- × 44-mm In-bore Cross Section Railgun by Miguel A. Del

  5. Suppression of transverse ablative Rayleigh-Taylor-like instability in the hole-boring radiation pressure acceleration by using elliptically polarized laser pulses

    CERN Document Server

    Wu, Dong; Qiao, B; Zhou, C T; Yan, X Q; Yu, M Y; He, X T

    2014-01-01

    It is shown that the transverse Rayleigh-Taylor-like (RT) instability in the hole boring radiation pressure acceleration can be suppressed by using elliptically polarized (EP) laser. A moderate ${J}\\times{B}$ heating of the EP laser will thermalize the local electrons, which leads to the transverse diffusion of ions, suppressing the short wavelength perturbations of RT instability. A proper condition of polarization ratio is obtained analytically for the given laser intensity and plasma density. The idea is confirmed by two dimensional Particle-in-Cell simulations, showing that the ion beam driven by the EP laser is more concentrated and intense compared with that of the circularly polarized laser.

  6. Beam induced heat loads on the beam-screens of the twin-bore magnets in the IRs of the HL-LHC

    CERN Document Server

    Iadarola, Giovanni; Rumolo, Giovanni

    2016-01-01

    The expected heat load induced on the beam screens has been evaluated for all the twin-bore magnets in the Insertion Regions (IRs) of the HL-LHC. The contribution from the impedance of the beam screen has been evaluated taking into account the presence of a longitudinal weld in the beam screen and the impact of the temperature and of the magnetic field on the resistivity of the surface. The contribution coming from electron cloud effects has been evaluated for different values of the Secondary Electron Yield of the surface based PyECLOUD build-up simulations.

  7. Cone Penetration Test and Soil Boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California

    Science.gov (United States)

    Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C.

    2009-01-01

    were drilled at the BGP for the purpose of monitoring pore-fluid pressure changes and aquifer-system deformation. One 308-m deep borehole contains six piezometers, the other two boreholes are 182 and 299 m deep and contain a dual-stage extensometer. To investigate the physical properties of the sediments, two phases of subsurface exploration were conducted. In the first phase, a USGS drilling crew obtained numerous core samples, 5.8 cm in diameter by 1.5 m long. The samples were extracted between July 28, 2006, and August 5, 2006; nine samples were tested for this study at the USGS soils laboratory in Menlo Park, California. Phase two began on June 22, 2006, when a seismic cone penetration test (SCPT) sounding was made to a depth of 32.3 m. Additional field work was completed May 8, 2007, with a hollow-stem auger boring that took continuous 9.8-cm-diameter samples from the depth interval of 6.1 to 10.7 m to supplement poor recovery from the first phase of sampling. These samples were also tested in the soils laboratory at the USGS.

  8. Vertical Lathe Rebuild and Turbine Guide Vane Bearing Hole Bored Together%立式车床改造与水轮机导叶轴孔同镗

    Institute of Scientific and Technical Information of China (English)

    戴仁华

    2001-01-01

    我厂经过不断地探索实践,总结出了一套较完整的水轮机备品修复工艺。通过在立式车床上改装立式镗头后,成功地解决了水轮机顶盖、底环导叶轴孔同镗,因而提高了大修回装精度和速度,经济效益显著,对地处山区的水电厂有着推广的价值。%For Repair for spare parts of turbine,a series of more integrated repairing techniques are summarized by our plant through continuous research and practice .Vertical boring head is refitted on vertical lathe to bore turbine head cover and guide vane bearing hole on bottom ring together .In this way,precision and speed for back installation in general overhaul is improved and economic benefit is obvious.It is valuable to popularize this technique at power plants in a mountainous area.

  9. 钻孔灌注斜桩施工技术研究%Study on the Construction Technique of Bored Cast-in-situ Battered Pile

    Institute of Scientific and Technical Information of China (English)

    潘术文

    2009-01-01

    相比普通钻孔灌注桩,钻孔灌注斜桩施工难度大,施工设备要求高.针对某港口工程特点及其所设计钢管钻孔灌注斜桩的施工要求,通过钻杌与钻具改造、施工工艺等一系列技术措施,保证了桩基础施工的顺利进行,相关的经验与方法值得类似工程借鉴.%Compared with that of ordinary cast-in-situ pile, the construction of bored cast-in-situ battered pile is more difficult and has a higher demand from the equipment. In the construction of bored cast-in-situ battered pile in a port project, the borer and drill used were transformed and special technical measures were adopted, which has ensured a smooth engineering progress. The experience can be consulted by similar engineering later.

  10. Some problems on the research and development of the application of methane draining boring technology to prevent hazards in underground coal mines in Vietnam

    Institute of Scientific and Technical Information of China (English)

    NGUYEN Xuan-Thao; NGUYEN Tran-Tuan; TRAN Dinh-Kien

    2009-01-01

    Underground coal mining activities in the Quangninh coal basin (in the North of Vietnam) have been carried out at a depth of-130 m to -150 m, and in the near future this mining depth will become -300 m and -500 m. Together with the increasing coal output, the quantity of methane and other mine gases emitted from coal beds during mining activi-ties will grow bigger and bigger. According to the forecast of the coal mining industry, if mines go deeper downward, all underground coal mines in the Quangninh basin will be classified into the mine group with the dangerous level of methane bearings. Mine gas control and management operations with conventional ventilation are less effective and entail high expenses. One of the main solutions is to carry out short, medium and long boreholes for controlling and recovering methane and other mine gases from coal beds before mining activities. Efficiency of drilling activities for methane gas recovery from coal seams with horizontal bore holes at underground coal mines depends on many factors in-cluding the mine gas draining borehole layout at the roadways, gas content in the coal beds, technologies for mine gas draining boring activities, and so on. Methane gas exists in the coal beds under the adhesive state with stable physical and chemical bonds. In or-der to recover these gases, it is necessary to carry out boreholes and create artificial joints (collecting pits) in coal beds with the impulse method (hydraulic separation method).

  11. PRELIMINARY RESEARCH OF BORING BEHAVIOR OF STORED GRAIN INSECTS%储粮害虫钻孔行为初步研究

    Institute of Scientific and Technical Information of China (English)

    姚渭; 王艳; 刘晓农; 杜燕萍

    2001-01-01

    设计的测定储粮害虫钻孔行为的装置由8种不同孔径的孔筛小瓶组成,筛孔直径分别为1.5mm、1.3mm、1.2mm、1.1mm、1mm、0.9mm、0.8mm及0.6mm,采用该装置对玉米象、米象、赤拟谷盗、杂拟谷盗、长头谷盗、谷蠹及锯谷盗单一种群和复合种群钻孔行为习性进行测试。测试结果表明,单一种群条件下,玉米象、米象、谷蠹及长头谷盗钻孔指数分别为0.28、0.30、0.35及0.24,钻孔习性基本相似;杂拟谷盗和赤拟谷盗钻孔指数分别为0.77和0.9;锯谷盗活动性较强,钻孔指数为0.57。讨论了玉米象、赤拟谷盗、长头谷盗、锯谷盗及谷蠹复合种群各害虫种类的钻孔习性,与单一种群比较,玉米象和谷蠹钻孔指数增高,赤拟谷盗和锯谷盗钻孔指数降低,长头谷盗钻孔指数变动不大。%An equipment used for testing boring behavior of grain insects was composed of 8 types of sieves,and their diameters are 1.5mm,1.3mm,1.2mm,1.lmm,1.0mm,0.9mm,0.8mm and 0.6mm respectively. The results showed that on condition of single population, boring indexes were 0.28 to Sitophilus zeamais Motschulsky,0.30 to Sitophilus oryzae (L.), 0.35 to Rhizopertha dominica (Fab.),0.24 to Latheticus oryzae Waterhouse. Their boring habit is similar,and 0.77 to Tribolium confusum Jacquelin du Val,0.9 to Tribolium castaneum (Herbst),0.57 to Oryzaephilus surinamensis (L.). Boring habits of Sitophilus zeamais Motschutsky,Tribolium castaneum (Herbst), Latheticus oryzae Waterhouse, Oryzaephilus surinamensis ( L ) and Rhizopertha dominica (Fab) in the composite population condition were discussed, and compared with single population, boring indexes of Sitophilus zeamais Motschulsk and Rhizopertha dominica (Fab.) are increased,Tribolium castaneum (Herbst) and Oryzaephilus surinamensis (L.) are decreased, and Latheticus oryzae Waterhouse has no obvious change.

  12. 弹丸结构参数对膛内运动的影响分析%Influence Analysis of Projectile Structural Parameters on Motion in Bore

    Institute of Scientific and Technical Information of China (English)

    岳永丰; 吴群彪; 沈培辉

    2013-01-01

    Based on the restitution coefficient of elastic collision, the projectile in-bore motion model was proposed with design parameters mainly considered. Analyze the influence of projectile’s main structural parameters on the motion. The approximate method that the restitution coefficient was seen as constant wasn’t used. Through the finite element simulation on the simplified model of gun-projectile system, the functional relation between the restitution coefficient and the radial velocity of the front bourrelet was acquired. The characteristic parameters of the 155mm shrapnel were used as the calculation parameters. Calculation and analysis about the various factors influence on the motion. The results show that there is general regularity between the projectile’s structural parameters and its in-bore motion characteristics. It is useful for selecting a reasonable structure for the projectile to ensuring the regular in-bore motion.%  基于弹性碰撞的恢复系数,提出一种重点考虑弹丸设计参数的弹丸膛内运动模型,分析了弹丸的主要结构参数对膛内运动的影响。模型中没有采用把恢复系数看作常数的近似方法,而是对弹炮系统的简化模型进行有限元仿真,得到恢复系数随前定心部径向速度变化的函数关系。以155 mm 榴弹的特征参数为计算量,对影响弹丸膛内运动的各因素进行了实例计算和分析。结果表明:弹丸结构参数的变化与膛内运动特性之间存在一般规律性,对选用合理的弹丸结构来保证膛内运动的正确性有一定的应用价值。

  13. Production of electron cyclotron resonance plasma by using multifrequencies microwaves and active beam profile control on a large bore electron cyclotron resonance ion source with permanent magnets.

    Science.gov (United States)

    Kato, Yushi; Watanabe, Takeyoshi; Matsui, Yuuki; Hirai, Yoshiaki; Kutsumi, Osamu; Sakamoto, Naoki; Sato, Fuminobu; Iida, Toshiyuki

    2010-02-01

    A new concept on magnetic field with all magnets on plasma production and confinement has been proposed to enhance efficiency of an electron cyclotron resonance (ECR) plasma for broad and dense ion beam source under the low pressure. The magnetic field configuration is constructed by a pair of magnets assembly, i.e., comb-shaped magnet which cylindrically surrounds the plasma chamber. The resonance zones corresponding to the fundamental ECR for 2.45 GHz and 11-13 GHz frequencies are constructed at different positions. The profiles of the plasma parameters in the ECR ion source are different from each frequency of microwave. Large bore extractor is set at the opposite side against the microwave feeds. It is found that differences of their profiles also appear at those of ion beam profiles. We conducted to launch simultaneously multiplex frequencies microwaves controlled individually, and tried to control the profiles of the plasma parameters and then those of extracted ion beam.

  14. Apparatus for determining the position of the cutting head of a boring or mining machine. Einrichtung zur Erfassung der Position des Schraemkopfes einer Vortriebs- oder Gewinnungsmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Schellenberg, E.; Zitz, A.; Droescher, B.

    1988-02-03

    Apparatus for determining the position of the cutting head of a boring or mining machine, characterised by a sensor, which is oriented relative to the longitudinal axis of the drift and which may be mounted in a drift a transmitter for transmitting electromagnetic radiation in the wave-length range of 1 ..mu..m to 10 cm on the cutting head and/or on a cutting arm and a telemeter for determining the distance of at least one reference point on the cutting head and/or cutting arm from the sensor and preferably an indicator for indicating the position of the cutting head relative to a required profile to be cut.

  15. Performance of 40-millimeter-bore ball bearings with lead- and lead-alloy-plated retainers in liquid hydrogen at 1.2 million DN

    Science.gov (United States)

    Brewe, D. E.; Wisander, D. W.; Scribbe, H. W.

    1972-01-01

    Forty-millimeter-bore ball bearings with lead- and lead-alloy-coated retainers were operated in liquid hydrogen at 30,000 rpm under a thrust load of 1780 N (400 lb.) Four different substrate materials were used for the retainer. Longer bearing run times were achieved with a lead-tin-copper alloy coating plated onto a leaded-bronze material (22.5 hr) and an aluminum-bronze alloy (19.3 hr). One bearing with a pure lead coating achieved the desired objective of 10 hr. This bearing had an aluminum - bronze substrate retainer and ran successfully for 12.4 hr. Additions of antimony to the lead provided an alloy coating with better wear resistance than pure lead; however, this coating was abrasive to the outer-race lands.

  16. 深基坑锚固工程中成孔技术%Bore-making Technique in the Anchorage Project of Deep Foundation Pit

    Institute of Scientific and Technical Information of China (English)

    曾庆辉

    2001-01-01

    Impact Spiral Drilling is a new bore-making techni que. Its usage in the anchorage project of deep foundation ditch can solve the p roblem of drilling in the soft and hard cross stratum. In this article, the auth or specially introduces the structure of impact spiral drill machine and its ope ration techniques.%冲击螺旋钻孔是一种新的成孔工艺,在深基坑的锚固技术中成功地解决了软硬互层、夹杂地层的钻进。本文详细介绍了冲击螺旋钻的构造和成孔操作技术。

  17. Morphological and ecological similarities: wood-boring beetles associated with novel xylose-fermenting yeasts, Spathaspora passalidarum gen. sp. nov. and Candida jeffriesii sp. nov.

    Science.gov (United States)

    Nguyen, Nhu H; Suh, Sung-Oui; Marshall, Christopher J; Blackwell, Meredith

    2006-10-01

    Ascomycete yeasts that both ferment and assimilate xylose were reported previously as associates of insects living in woody substrates. Most notable have been reports of Pichia stipitis-like yeasts that are widely associated with the wood-boring beetle, Odontotaenius disjunctus (Coleoptera: Passalidae), in the eastern United States. Our continuing investigation of insect gut yeasts has lead to the discovery of two new xylose-fermenting yeasts that phylogenetic analysis places as sister taxa. The beetle hosts, O. disjunctus and Phrenapates bennetti (Coleoptera: Tenebrionidae), are similar in habitat and appearance, and the presence of similar gut yeasts is an additional common feature between them. Here we describe the new yeast genus Spathaspora, the type species S. passalidarum, and its sister taxon Candida jeffriesii and discuss their natural history, including a comparison with Pichia stipitis, another member of a guild of xylose-fermenting yeasts with similar metabolic traits. In addition a morphologically distinct yeast ascospore type is described for Spathaspora.

  18. Paleomagnetism and 40Ar/39Ar geochronology of the Plio-Pleistocene Boring Volcanic Field: Implications for the geomagnetic polarity time scale and paleosecular variation

    Science.gov (United States)

    Hagstrum, Jonathan T.; Fleck, Robert J.; Evarts, Russell C.; Calvert, Andrew T.

    2017-01-01

    Paleomagnetic directions and 40Ar/39Ar ages have been determined for samples of lava flows from the same outcrops, where possible, for 84 eruptive units ranging in age from 3200 ka to 60 ka within the Boring Volcanic Field (BVF) of the Pacific Northwest, USA. This study expands upon our previous results for the BVF, and compares the combined results with the current geomagnetic polarity time scale (GPTS). Lava flows with transitional directions were found within the BVF at the Matuyama-Brunhes and Jaramillo-Matuyama polarity boundaries, and replicate ages corresponding to these and other boundaries have been newly ascertained. Although the BVF data generally agree with GPTS chronozone boundaries, they indicate that onset of the Gauss-Matuyama transition and Olduvai subchron occurred significantly earlier than given in the current time scale calibration. Additional comparisons show that the BVF results are consistent with recent statistical models of geomagnetic paleosecular variation.

  19. On improvement of thermal control small-bore tube laying craft%热控小径管敷设工艺改进

    Institute of Scientific and Technical Information of China (English)

    任强

    2011-01-01

    介绍了热控小径管敷设工艺改进方法,通过将变送器原水平接管方式改变为下进管方式,节约了部分管路材料的同时使热控管路的排污更彻底更清洁,从而有效提高了热控仪表的安全性、准确性,值得推广。%The paper introduces the improvement methods for the thermal control small-bore tube laying craft,changes the horizontal tube connection way of transducers into the downward tube way,saves the partial tube materials and has the more complete and clearer discharge of pollutions of the thermal control tubes,so as to improve the safety and the accuracy of the thermal control meters,and to further extend the technique.

  20. Application of bored pile in a hydraulic project%钻孔灌注桩在某水利工程中的应用

    Institute of Scientific and Technical Information of China (English)

    王荣晶

    2013-01-01

      通过某水利工程实例,介绍了钻孔灌注桩的施工流程及质量控制措施。分析了钻孔灌注桩的施工过程中常见的沉笼、浮笼、导管拔空等问题的原因,并提出了相应的处理措施。%Taking a hydraulic project as example, an introduction was made on the construction process and quality control of bored pile. The author also analyzed the causes for the common problems such as sinking cage, floating cage, mud flowing into pilot pipe etc., and put forward corresponding solution measures.

  1. 炮孔装药隔离器的研制与工程应用%RESEARCH AND ENGINEERING APPLICATION OF EXPLOSIVE- DEBRIS ISOLATOR IN BORE-HOLE

    Institute of Scientific and Technical Information of China (English)

    殷延军

    2011-01-01

    针对爆破传统装药工艺存在炸药浪费的问题,研制了碟盘形橡胶药碴隔离器和盆形塑料药碴隔离器.通过对金堆城露天矿含水和无水孔底装药过程及填塞过程中岩屑与乳化炸药混合模式的模拟试验研究及大量现场试验,获得一套具有自主知识产权的药碴隔离和装药工艺改进了技术.该技术改进了传统装药工艺,使炮孔底部残留岩屑和填塞用岩屑与炸药彻底隔离,避免了药碴混合造成炸药浪费,达到降低爆破成本的目的.%Due to wasting explosive in the traditional charge craft, a rubber explosion-debris isolator with dish shape and a plastic explosion-debris isolator with basin shape were researched and made. Through simulative and field experimental research to mixture mode of debris and emulsified explosion in charging and tamping under the bottom of bore-hole with water and without water conditions in the jind-uicheng open-pit mine, a improvement technique for explosion-debris isolation and charging craft, with independent intellectual property rights, was acquired. The technique improved traditional charge craft, isolated explosion from debris residue in the bottom of bore-hole and debris tamped, avoided waste of explosion due to mixing explosion and debris, and attained to the purpose of reducing blasting cost.

  2. MR-sequences for prostate cancer diagnostics: validation based on the PI-RADS scoring system and targeted MR-guided in-bore biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Schimmoeller, Lars; Quentin, Michael; Buchbender, Christian; Antoch, Gerald; Blondin, Dirk [University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Arsov, Christian; Hiester, Andreas; Rabenalt, Robert; Albers, Peter [University Dusseldorf, Medical Faculty, Department of Urology, Dusseldorf (Germany)

    2014-10-15

    This study evaluated the accuracy of MR sequences [T2-, diffusion-weighted, and dynamic contrast-enhanced (T2WI, DWI, and DCE) imaging] at 3T, based on the European Society of Urogenital Radiology (ESUR) scoring system [Prostate Imaging Reporting and Data System (PI-RADS)] using MR-guided in-bore prostate biopsies as reference standard. In 235 consecutive patients [aged 65.7 ± 7.9 years; median prostate-specific antigen (PSA) 8 ng/ml] with multiparametric prostate MRI (mp-MRI), 566 lesions were scored according to PI-RADS. Histology of all lesions was obtained by targeted MR-guided in-bore biopsy. In 200 lesions, biopsy revealed prostate cancer (PCa). The area under the curve (AUC) for cancer detection was 0.70 (T2WI), 0.80 (DWI), and 0.74 (DCE). A combination of T2WI + DWI, T2WI + DCE, and DWI + DCE achieved an AUC of 0.81, 0.78, and 0.79. A summed PI-RADS score of T2WI + DWI + DCE achieved an AUC of 0.81. For higher grade PCa (primary Gleason pattern ≥ 4), the AUC was 0.85 for T2WI + DWI, 0.84 for T2WI + DCE, 0.86 for DWI + DCE, and 0.87 for T2WI + DWI + DCE. The AUC for T2WI + DWI + DCE for transitional-zone PCa was 0.73, and for the peripheral zone 0.88. Regarding higher-grade PCa, AUC for transitional-zone PCa was 0.88, and for peripheral zone 0.96. The combination of T2WI + DWI + DCE achieved the highest test accuracy, especially in patients with higher-grade PCa. The use of ≤2 MR sequences led to lower AUC in higher-grade and peripheral-zone cancers. (orig.)

  3. Test-retest reliability of automated whole body and compartmental muscle volume measurements on a wide bore 3T MR system

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Marianna S.; Newman, David; Kasmai, Bahman; Greenwood, Richard; Malcolm, Paul N. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Leinhard, Olof Dahlqvist [Linkoeping University, Center for Medical Image Science and Visualization, Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences, Linkoeping (Sweden); Karlsson, Anette; Borga, Magnus [Linkoeping University, Center for Medical Image Science and Visualization, Linkoeping (Sweden); Linkoeping University, Department of Biomedical Engineering, Linkoeping (Sweden); Rosander, Johannes [Advanced MR Analytics AB, Linkoeping (Sweden); Toms, Andoni P. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich (United Kingdom); Radiology Academy, Cotman Centre, Norwich, Norfolk (United Kingdom)

    2014-09-15

    To measure the test-retest reproducibility of an automated system for quantifying whole body and compartmental muscle volumes using wide bore 3 T MRI. Thirty volunteers stratified by body mass index underwent whole body 3 T MRI, two-point Dixon sequences, on two separate occasions. Water-fat separation was performed, with automated segmentation of whole body, torso, upper and lower leg volumes, and manually segmented lower leg muscle volumes. Mean automated total body muscle volume was 19.32 L (SD9.1) and 19.28 L (SD9.12) for first and second acquisitions (Intraclass correlation coefficient (ICC) = 1.0, 95 % level of agreement -0.32-0.2 L). ICC for all automated test-retest muscle volumes were almost perfect (0.99-1.0) with 95 % levels of agreement 1.8-6.6 % of mean volume. Automated muscle volume measurements correlate closely with manual quantification (right lower leg: manual 1.68 L (2SD0.6) compared to automated 1.64 L (2SD 0.6), left lower leg: manual 1.69 L (2SD 0.64) compared to automated 1.63 L (SD0.61), correlation coefficients for automated and manual segmentation were 0.94-0.96). Fully automated whole body and compartmental muscle volume quantification can be achieved rapidly on a 3 T wide bore system with very low margins of error, excellent test-retest reliability and excellent correlation to manual segmentation in the lower leg. (orig.)

  4. Kinematic change of the meniscus and the tibiofemoral joint space in asymptomatic volunteers using a wide bore 3T closed MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eugene; Kim, Yeo Ju; Kim, Mi Young; Cho, Soon Gu [Inha University Hospital, Department of Radiology, Choong-gu, Incheon (Korea, Republic of); Cha, Jang Gyu [Soonchunhyang University Hospital, Department of Radiology, Bucheon (Korea, Republic of); Lee, Dae Hyung [Inha University Hospital, Clinical Trail Center, Incheon (Korea, Republic of); Kim, Ryuh Sup [Inha University Hospital, Department of Orthopedic Surgery, Incheon (Korea, Republic of)

    2015-10-15

    To evaluate kinematic changes in menisci and tibiofemoral joint spaces in extension and flexion using asymptomatic volunteers using a wide-bore 3-T closed MRI system. Twenty-two knees from asymptomatic volunteers were examined in knee extension and flexion using a 3-T MRI (sagittal 2D FSE T2-weighted sequence and sagittal 3D isotropic FSE proton density-weighted cube sequence). The meniscal positions, meniscal floating and flounce were evaluated. The widths of the medial and lateral tibiofemoral joint spaces and coronal tibiofemoral angles were measured. In the anteroposterior direction, meniscal extrusion was most frequently seen in the anterior horn of the medial menisci (100 %) in extensions (maximum 6.04 mm). Most of the menisci moved significantly to the posterior side from extension to flexion. The anteroposterior meniscal movement was the greatest for the anterior horn of the medial meniscus and least for the posterior horn of the medial meniscus. In the mediolateral direction, meniscal extrusion was seen in 52 % of the medial menisci in extensions (maximum 1.91 mm) and 29 % of lateral menisci in flexions (maximum 2.36 mm). From the extension to flexion, all medial and lateral menisci moved significantly to the lateral side. Meniscal floating was frequently observed in the posterior horn of medial menisci in extension. Meniscal flounce was frequently seen in lateral menisci in flexion with a widened lateral tibiofemoral joint space gap. The coronal tibiofemoral angle showed medial wedging in flexion, but not in extension. Wide-bore 3-T closed MRI revealed significant kinematic changes in the menisci and tibiofemoral joint spaces in asymptomatic volunteers. (orig.)

  5. Magnetic resonance-guided upper abdominal biopsies in a high-field wide-bore 3-T MRI system: feasibility, handling, and needle artefacts

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Jens-Peter; Langner, Soenke; Hegenscheid, Katrin; Hosten, Norbert; Puls, Ralf [Ernst Moritz Arndt University of Greifswald, Department of Radiology, Greifswald (Germany); Evert, Matthias [Ernst Moritz Arndt University of Greifswald, Department of Pathology, Greifswald (Germany); Kickhefel, Antje [Siemens Healthcare, Erlangen (Germany)

    2010-10-15

    To investigate the feasibility and handling of abdominal MRI-guided biopsies in a 3-T MRI system. Over a 1-year period, 50 biopsies were obtained in 47 patients with tumours of the upper abdominal organs guided by 3-T MRI with a large-bore diameter of 70 cm. Lesions in liver (47), spleen (1) and kidney (2) were biopsied with a coaxial technique using a 16-G biopsy needle guided by a T1-weighted three-dimensional gradient recalled echo volumetric interpolated breath-hold examination (T1w-3D-GRE-VIBE) sequence. Sensitivity, specificity, accuracy, complication rate, interventional complexity, room/intervention time and needle artefacts were determined. A sensitivity of 0.93, specificity of 1.0 and accuracy of 0.94 were observed. Three patients required a rebiopsy. There was a minor complications rate of 13.6%, and no major complications were observed. Histopathology revealed 38 malignant lesions, and 3-month follow-up confirmed 9 benign lesions. Mean lesion diameter was 3.4 {+-} 3.1 cm (50% being smaller than 2 cm). Mean needle tract length was 10.8 {+-} 3.3 cm. Median room time was 42.0 {+-} 19.8 min and intervention time 9.3 {+-} 8.1 min. Needle artefact size was about 9-fold greater for perpendicular access versus access parallel to the main magnetic field. Biopsies of the upper abdomen can be performed with great technical success and easy handling because of the large-bore diameter. The MRI-guided biopsy needle had an acceptable susceptibility artefact at 3 T. However future research must aim to reduce the susceptibility effects of the biopsy systems. (orig.)

  6. Study of a transaugmented two-stage small circular-bore railgun for injection of hypervelocity hydrogen pellets as a fusion reactor refueling mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Tompkins, M.W.; Anderson, M.A.; Feng, Q.; Zhang, J.; Kim, K. [Univ. of Illinois, Urbana, IL (United States)

    1997-01-01

    Injection of hypervelocity hydrogen pellets has become widely accepted as the most effective means of refueling magnetically confined fusion reactors. Pellet velocities on the order of 10 km/s are desired and hydrogen pellet erosion during acceleration must be minimized. It is important to maintain uniform bore surfaces during repetitive shots, implying that, if a railgun is to be used to accelerate the pellets, damage to the sidewalls and rails of the railgun due to local heating must be limited. In order to reduce the amount of power dissipated within the bore and increase the propulsive force generated by the plasma-arc armature while minimizing losses due to pellet, rail, and sidewall ablation, the authors have employed a magnetic field transaugmentation mechanism consisting of a two-turn pulsed electromagnet. The two-stage gun consists of a light-gas gun which accelerates a 4- to 5-mg pellet to a speed around 1.2 km/s and injects it into the plasma-arc armature railgun. Currently, they have achieved a final output velocity for a hydrogen pellet of 2.11 km/s with a time-averaged acceleration of 4,850 km/s{sup 2} using a 58-cm railgun pulsed with a peak rail current of 9.2 kA and 28.0 kA of transaugmentation current. This paper will present a description of the hydrogen-pellet-injector railgun system, a discussion of the data on hydrogen pellet acceleration, and projections for future systems.

  7. Feasibility of diffusion-weighted magnetic resonance imaging in patients with juvenile idiopathic arthritis on 1.0-T open-bore MRI

    Energy Technology Data Exchange (ETDEWEB)

    Barendregt, Anouk M.; Nusman, Charlotte M. [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Hemke, Robert; Lavini, Cristina; Maas, Mario [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Amiras, Dimitri [Imperial College Healthcare NHS Trust, Radiology Department, St. Mary' s Hospital, Paddington, London (United Kingdom); Kuijpers, Taco W. [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands)

    2015-12-15

    To evaluate the feasibility of non-invasive diffusion-weighted imaging (DWI) of the knee of children with juvenile idiopathic arthritis (JIA) and, further, to analyze the apparent diffusion coefficient (ADC) levels to distinguish synovium from effusion. Standard magnetic resonance imaging of the knee including post-contrast imaging was obtained in eight patients (mean age, 12 years 8 months, five females) using an open-bore magnetic resonance imaging system (1.0 T). In addition, axially acquired echo-planar DWI datasets (b-values 0, 50, and 600) were prospectively obtained and the diffusion images were post-processed into ADC{sub 50-600} maps. Two independent observers selected a region of interest (ROI) for both synovium and effusion using aligned post-contrast images as landmarks. Mann-Whitney U test was performed to compare ADC synovium and ADC effusion. DWI was successfully obtained in all patients. When data of both observers was combined, ADC synovium was lower than ADC effusion in the ROI in seven out of eight patients (median, 1.92 x 10{sup -3} mm{sup 2}/s vs. 2.40 x 10{sup -3} mm{sup 2}/s, p = 0.006, respectively). Similar results were obtained when the two observers were analyzed separately (observer 1: p = 0.006, observer 2: p = 0.04). In this pilot study, on a patient-friendly 1.0-T open-bore MRI, we demonstrated that DWI may potentially be a feasible non-invasive imaging technique in children with JIA. We could differentiate synovium from effusion in seven out of eight patients based on the ADC of synovium and effusion. However, to select synovium and effusion on DWI, post-contrast images were still a necessity. (orig.)

  8. A design for high precision boring auxiliary device with multi-station synchronous processing function%一种实现多工位同步加工的高精度镗孔辅助装置的研制

    Institute of Scientific and Technical Information of China (English)

    吴世雄

    2013-01-01

    Designs a boring auxiliary device specifically for floor-type boring machine in mechanical processing industry ,and de-scribes its working principle .In order to improve the machining accuracy of traditional floor-type boring machine and make it pro-duce better products,the high precision boring auxiliary device with multi-station simultaneous processing function referred has the features of high positioning accuracy ,the amount of feed readable ,simple operation & adjustment ,and etc.In addition,the device can be transformed according to the specific situation of machine tool to meet the special requirements of different equipments .%为提高传统型落地镗机床的加工精度,介绍一种针对落地镗床设计的镗孔辅助装置,并对其工作原理进行阐述。所设计的多工位同步加工的高精度镗孔辅助装置具有定位精度高、进刀量可读、操作及调整简单等特性。此外,该镗孔辅助装置可根据机床的具体情况进行相关改造,满足不同设备的特殊要求。

  9. Drilling mud additive for the release of jammed drill pipes in a well bore. Additiv for tilsetning til boreslam, eller for frigjoering av fastkjoerte boreroer i et borehull og anvendelse av additivet for disse formaal

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, d.E.; Mouten, R.J.; Moecek, C.J.

    1986-04-21

    The invention concerns a drilling mud additive to release jammed drill pipes in a well bore. The additive is a mixture of imideazolene/amide, diethanolamide, tall oil fatty acids, and a non-polluting/biodegradable - and non-fluorescent oil.

  10. The Design of a Fining Boring Machine for Three Kinds of Holes on the WD12 Cylinder%WD12气缸体三轴孔精镗机床的设计

    Institute of Scientific and Technical Information of China (English)

    韩海群; 李春燕

    2011-01-01

    为保证缸体曲轴孔、凸轮轴孔和惰轮孔的加工精度,设计了WD12气缸体三轴孔精镗机床,确定了单面卧式总体方案、加工示意图和电气动作循环表.曲轴孔和凸轮轴孔均是多档间断的长孔,其精度要求高.为提高镗杆的刚度,除尽量加粗镗杆、设置中间支承外,选择德国玛帕生产的直线镗杆和浮动接头及美国GATCO生产的滚动导向套保证精度.采用"一面两销"的定位方案和液压夹紧机构.并对镗模安装提出了具体的要求.设备经十个月的研制,得到用户的认可.%To ensure the accuracy of three kinds of holes of crankshaft, camshaft and idlers, a triaxial fine boring machine for the WD12 cylinder is designed. The singleside horizontal boring is determined which include the overall program machining sketch chart and electrical action cycle table The holes of crankshaft and camshaft are long with intermittent gap and high precision To improve the rigidity of boring bars,some methods are applied. They include making the boring bar thicker, adding the intermediate support,choosing the line boring bars and floating holders of Mapa, and selecting the precision rotary bushings of GATCO. Put to use the fixing scheme of "one plane and two pins" and hydraulic clamping facility and make a specific request of installation requirements of the boring mold in the machine. After ten months of research, the boring machine get user's acceptance

  11. In vivo open-bore MRI reveals region- and sub-arc-specific lengthening of the unloaded human posterior cruciate ligament.

    Directory of Open Access Journals (Sweden)

    Alison J King

    Full Text Available Open-bore MRI scanners allow joint soft tissue to be imaged over a large, uninterrupted range of flexion. Using an open-bore scanner, 3D para-sagittal images of the posterior cruciate ligament (PCL were collected from seven healthy subjects in unloaded, recumbent knee extension and flexion. PCL length was measured from one 2D MRI slice partition per flexion angle, per subject. The anterior surface of the PCL lengthened significantly between extension and flexion (p<0.001. Conversely, the posterior surface did not. Changes were not due to the PCL moving relative to the 2D slice partition; measurements made from 3D reconstructions, which compensated for PCL movement, did not differ significantly from measurements made from 2D slice partitions. In a second experiment, videos of knee flexion were made by imaging two subjects at several flexion angles. Videos allowed soft tissue tracking; examples are included. In a third experiment, unloaded knees of seven healthy, recumbent subjects were imaged at extension and at 40°, 70°, 90°, 100°, 110° and 120° flexion. The distance between PCL attachments increased between extension and 100°, and then decreased (p<0.001. The anterior surface of the PCL lengthened over the flexion angles measured (p<0.01. The posterior surface of the PCL lengthened between extension and 40° and then shortened (p<0.001. Both attachment separation and anterior surface length increased dramatically between extension and 40°, but varied less afterwards. Results indicate that PCL dynamics differ between terminal extension and active function sub-arcs. Also, attachment separation cannot predict the lengthening of all parts of the PCL, nor can lengthening of one part of the PCL predict the lengthening of another part. A potential connection between lengthening and loading is discussed. We conclude that low-field MRI can assess ligament lengthening during flexion, and that the dynamics of the PCL for any given region and sub

  12. Thermal Characteristic Analysis of Ram of CNC Gantry Milling and Boring Machine%数控龙门镗铣床滑枕热特性分析

    Institute of Scientific and Technical Information of China (English)

    王元伦; 彭梁锋; 李绍萍; 张文坤

    2016-01-01

    滑枕是影响数控龙门镗铣床加工精度的关键部件。针对切削加工中存在的实际问题,确立导致滑枕热变形的热源,对轴承生热率进行计算,建立热变形数学模型;对滑枕进行热性能分析,并对主轴轴系结构进行改进。结果表明:滑枕的最高温度在主轴轴承支承处,为64.13℃;滑枕的最大的热变形在主轴轴承支承端,为38.9μm;采用冷却套结构、后轴承自由支承方式,减小主轴、滑枕热变形,从而提高数控龙门镗铣床加工精度。%Ram is the key part influencing the machining accuracy of gantry type boring and milling machine .Aiming at actual problems in cutting , the heat sources causing thermal deformation of ram were found out .The heat generation rate of bearings was cal-culated, and the mathematic model of thermal deformation was set up .The thermal performance on the ram was analyzed , and the structure of bearings of the spindle unit was improved .The result shows that the highest heat point of 64.13℃is at the bearing support part, and the biggest thermal deformation part which is 38.9μm, it is at the spindle bearing support end .Using the cooling sleeve unit and rear bearing free support structure can reduce the thermal deformation of spindle and ram , and so to improve the machining accura-cy of gantry type boring and milling machine .

  13. 穿层钻孔煤孔段造斜钻进技术研究%Directional Drilling for Bore Hole Interval Through Coal Seam

    Institute of Scientific and Technical Information of China (English)

    童碧; 孙新胜; 王力; 徐保龙; 贾明群; 石会田

    2013-01-01

    The paper introduces the borehole trajectory design and directional drilling technique for the coal seam for gas drainage.Directional drilling has been tested to make the bore hole path turn downward at the coal interval to extend the travelling length of the borehole in the coal seam;thus improving gas drainage efficiency.During drilling, the drilling string configuration of high build-rates was used to make the deflecting rate up to 2 °/m at maximum.Compared to conventional drilling technology, the borehole interval in the coal seam is extended 2.45 times.%介绍了抽放瓦斯穿层孔煤孔段造斜钻进的钻孔轨迹设计及钻进工艺,在试验中采用定向钻进技术,使穿层钻孔轨迹在煤孔段产生向下弯曲,延长了煤孔段长度,提高瓦斯抽放效率。施工中使用强造斜组合钻具钻进,使钻孔最大造斜强度达到2°/m,相对于常规钻进工艺,煤孔段最大延长2.45倍。

  14. Enantioselective column coupled electrophoresis employing large bore capillaries hyphenated with tandem mass spectrometry for ultra-trace determination of chiral compounds in complex real samples.

    Science.gov (United States)

    Piešťanský, Juraj; Maráková, Katarína; Kovaľ, Marián; Havránek, Emil; Mikuš, Peter

    2015-12-01

    A new multidimensional analytical approach for the ultra-trace determination of target chiral compounds in unpretreated complex real samples was developed in this work. The proposed analytical system provided high orthogonality due to on-line combination of three different methods (separation mechanisms), i.e. (1) isotachophoresis (ITP), (2) chiral capillary zone electrophoresis (chiral CZE), and (3) triple quadrupole mass spectrometry (QqQ MS). The ITP step, performed in a large bore capillary (800 μm), was utilized for the effective sample pretreatment (preconcentration and matrix clean-up) in a large injection volume (1-10 μL) enabling to obtain as low as ca. 80 pg/mL limits of detection for the target enantiomers in urine matrices. In the chiral CZE step, the different chiral selectors (neutral, ionizable, and permanently charged cyclodextrins) and buffer systems were tested in terms of enantioselectivity and influence on the MS detection response. The performance parameters of the optimized ITP - chiral CZE-QqQ MS method were evaluated according to the FDA guidance for bioanalytical method validation. Successful validation and application (enantioselective monitoring of renally eliminated pheniramine and its metabolite in human urine) highlighted great potential of this chiral approach in advanced enantioselective biomedical applications.

  15. Determination of metals in lubricating oils by flame atomic absorption spectrometry using a single-bore high-pressure pneumatic nebulizer.

    Science.gov (United States)

    Mora, J; Todolí, J L; Sempere, F J; Canals, A; Hernandis, V

    2000-12-01

    The behaviour of a single-bore high-pressure pneumatic nebulizer (SBHPPN) as a tool for the analysis of lubricating oils by flame atomic absorption spectrometry (FAAS) was investigated. The effects of the sample oil content [from 10% to 100% (w/w) oil in 4-methylpentan-2-one, IBMK] and the carrier nature (IBMK and methanol) on the characteristics of the aerosols generated, on the analyte transport efficiency and on the analytical figures of merit in FAAS were studied. A pneumatic concentric nebulizer (PCN) was used for comparison. Increasing the oil content increases the viscosity of the sample. With the PCN this gives rise to coarser aerosols, making it impossible to nebulize samples with an oil content higher than 70% (w/w). Using the SBHPPN, the viscosity of the sample scarcely affects the characteristics of the primary aerosols. Hence, the SBHPPN is able, by using the appropriate carrier, to nebulize pure lubricating oils. Among the carriers tested, IBMK is the most advisable because it is fully miscible with all the oil samples. The SBHPPN provides higher sensitivities and lower limits of detection than the PCN. Compared with a method based on organic dilution, the use of the SBHPPN for the direct analysis of lubricating oils by FAAS makes it possible, in addition to increasing the analysis throughput, to detect elements at lower concentrations. Moreover, the SBHPPN provides similar results to those obtained using a previous acid digestion step.

  16. Effect of larval growth conditions on adult body mass and long-distance flight endurance in a wood-boring beetle: Do smaller beetles fly better?

    Science.gov (United States)

    Brown, Stav; Soroker, Victoria; Ribak, Gal

    2017-02-22

    The tropical fig borer, Batocera rufomaculata De Geer, is a large beetle that is a pest on a number of fruit trees, including fig and mango. Adults feed on the leaves and twigs and females lay their eggs under the bark of the tree. The larvae bore into the tree trunk, causing substantial damage that may lead to the collapse and death of the host tree. We studied how larval development under inferior feeding conditions (experienced during development in dying trees) affects flight endurance in the adult insect. We grew larvae either in their natural host or on sawdust enriched with stale fig tree twigs. Flight endurance of the adults was measured using a custom-built flight-mill. Beetles emerging from the natural host were significantly larger but flew shorter distances than beetles reared on less favourable substrates. There was no difference in the allometric slope of wing area with body mass between the beetles groups; however flight muscle mass scaled with total body mass with an exponent significantly lower than 1.0. Hence, smaller beetles had proportionally larger flight muscles. These findings suggest that beetles that developed smaller as a result from poor nutritional conditions in deteriorating hosts, are better equipped to fly longer distances in search of a new host tree.

  17. Scale-up protein separation on stainless steel wide bore toroidal columns in the type-J counter-current chromatography.

    Science.gov (United States)

    Guan, Yue Hugh; Hewitson, Peter; van den Heuvel, Remco N A M; Zhao, Yan; Siebers, Rick P G; Zhuang, Ying-Ping; Sutherland, Ian

    2015-12-11

    Manufacturing high-value added biotech biopharmaceutical products (e.g. therapeutic proteins) requires quick-to-develop, GMP-compliant, easy-to-scale and cost effective preparatory chromatography technologies. In this work, we describe the construction and testing of a set of 5-mm inner diameter stainless steel toroidal columns for use on commercially available preparatory scale synchronous J-type counter-current chromatography (CCC) machinery. We used a 20.2m long column with an aqueous two-phase system containing 14% (w/w) PEG1000 and 14% (w/w) potassium phosphate at pH 7, and tested a sample loading of 5% column volume and a mobile phase flow rate of 20ml/min. We then satisfactorily demonstrated the potential for a weekly protein separation and preparation throughput of ca. 11g based on a normal weekly routine for separating a pair of model proteins by making five stacked injections on a single portion of stationary phase with no stripping. Compared to our previous 1.6mm bore PTFE toroidal column, the present columns enlarged the nominal column processing throughput by nearly 10. For an ideal model protein injection modality, we observed a scaling up factor of at least 21. The 2 scales of protein separation and purification steps were realized on the same commercial CCC device.

  18. Development of a new dispersive liquid-liquid microextraction method in a narrow-bore tube for preconcentration of triazole pesticides from aqueous samples.

    Science.gov (United States)

    Farajzadeh, Mir Ali; Djozan, Djavanshir; Khorram, Parisa

    2012-02-03

    In the present work a new, simple, rapid and environmentally friendly dispersive liquid-liquid microextraction (DLLME) method has been developed for extraction/preconcentration of some triazole pesticides in aqueous samples and in grape juice. The extract was analyzed with gas chromatography-flame ionization detection (GC-FID) or gas chromatography-mass spectrometry (GC-MS). The DLLME method was performed in a narrow-bore tube containing aqueous sample. Acetonitrile and a mixture of n-hexanol and n-hexane (75:25, v/v) were used as disperser and extraction solvents, respectively. The effect of several factors that influence performance of the method, including the chemical nature and volume of the disperser and extraction solvents, number of extraction, pH and salt addition, were investigated and optimized. Figures of merit such as linearity (r(2)>0.995), enrichment factors (EFs) (263-380), limits of detection (0.3-5 μg L(-1)) and quantification (0.9-16.7 μg L(-1)), and relative standard deviations (3.2-5%) of the proposed method were satisfactory for determination of the model analytes. The method was successfully applied for determination of target pesticides in grape juice and good recoveries (74-99%) were achieved for spiked samples. As compared with the conventional DLLME, the proposed DLLME method showed higher EFs and less environmental hazards with no need for centrifuging.

  19. Effect of Chipping and Solarization on Emergence and Boring Activity of a Recently Introduced Ambrosia Beetle (Euwallacea sp., Coleoptera: Curculionidae: Scolytinae) in Southern California.

    Science.gov (United States)

    Eatough Jones, Michele; Paine, Timothy D

    2015-08-01

    Polyphagous shot hole borer (Euwallacea sp., Coleoptera: Curculionidae: Scolytinae) has recently invaded southern California. The beetle, along with its associated fungi, Fusarium euwallaceae, Graphium sp., and Acremonium sp., causes branch dieback and tree mortality in a large variety of tree species including avocado (Persea americana Mill.) and box elder (Acer negundo L.). With the spread of the beetle through Los Angeles, Orange, and San Diego Counties in California, there is increasing concern that felled trees and pruned branches infested with polyphagous shot hole borer should receive sanitation treatment to reduce the potential spread of the beetle from the movement of untreated wood. We tested two sanitation methods to reduce beetle populations, chipping with a commercial chipper and solarization by covering logs with clear or black plastic in full sun. Both chipping and solarization decreased beetle emergence and boring activity compared to untreated control logs. Chipping was most effective for chip sizes <5 cm. Solarization was most effective using clear polyethylene sheeting during hot summer months, particularly August, when daily maximum temperatures were ≥35°C. Beetles persisted for 2 mo or more when solarization was applied during the spring or fall.

  20. A device for taking samples of scale from bore pipes used for collecting groundwater; Dispositivo para la toma de muestras de incrustaciones en tuberias de sondeos en la captacion de aguas subterraneas

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Rubio, J.; Ruano Magan, P. [Tecnologias y Servicios Agrarios, S. A. (Spain); Gonzalez Yelamos, J. [Universidad Autonoma de Madrid (Spain); Rebollo Ferreiro, L. F. [Universidad de Alcala (Spain)

    2000-07-01

    A study was made of the problem of corrosion/scale in water collection bore pipes, beginning with a review of the existing literature. This led to the conclusion that thorough knowledge of such phenomena requires taking samples from the walls of the pipes and filters to determine the physiocochemical and biological details. A new instrument, based on a previous appliance, has been developed for this purpose. It has a pair of arms and is capable of going down inside the well or bore hole, generally with a video camera attached. It has a cup on the end of each arm that can scrape the wall, catch the sample and protect it with a lid. A prototype has proved to be efficient at obtaining representative samples that can be analysed to determine the corrosion/scale processes. (Author) 9 refs.

  1. Measurement of In-Bore Projectile Motion Posture in Half Constraint Region%半约束期弹丸膛内运动姿态测试方法

    Institute of Scientific and Technical Information of China (English)

    郭泽成; 陈明; 张飞猛

    2013-01-01

    Based on domestic and foreign measurement for the motion posture of in-bore projectile currently, make the research on real time testing theory and method of in-bore projectile motion posture in half constraint region. Introduce current domestic and foreign in-bore projectile motion posture measurement methods, including high speed camera method, laser optics lever method and magnetism sensor method and so on. Comparing advantages and disadvantages of each method, summarize the important meaning of new in-bore projectile motion posture measurement method for artillery design and firing precision improvement. The research provides reference for improving artillery firing precision, and supporting firing dynamics test.%  针对目前国内外膛内弹丸姿态研究现状,对半约束期弹丸姿态变化的实时测试理论和方法进行研究。介绍当前国内外火炮弹丸膛内运动姿态的测量方法,包括高速摄影法、激光光学杠杆法和磁传感器法等,比较各种方法的优缺点,并总结研究新的火炮弹丸膛内运动姿态测量方法对于火炮设计和提高火炮射击精度的重要意义。该研究可为提高火炮射击精度、支撑发射动力学的实验研究提供参考。

  2. 缸孔珩磨表面微观质量评定方法的制定及应用%Establishment of Evaluation Method of Cylinder Bore Honing Surface Quality

    Institute of Scientific and Technical Information of China (English)

    李建华; 周跃钢; 王祖化; 彭科国; 李卫国

    2011-01-01

    Among the parameters which affect cylinder bore honing surface quality, parameters like profile bearing length ratio, ten point height of irregularities, profile waviness, valley mean spacing which affect engine cylinder bore cross hatch honing characteristic are selected, and different weights are allocated to those parameters according to different affect, this is used as a new method in the evaluation of cylinder bore honing surface quality. This method is tested in many commercial vehicle engine series, correctness and adaptability of this evaluation method are verified.%从诸多发动机缸孔珩磨表面微观质量的评价参数中,选择了影响发动机缸孔网纹珩磨特性的轮廓支撑长度率、微观不平度十点高度、轮廓波度、谷沟平均间距等参数,并根据各参数的影响程度制定了不同的权重,将其作为一种新的评定方法用于缸孔珩磨表面微观质量的的评定.在多种商用车系列发动机上进行了检测,验证了该评定方法的正确性和适用性.

  3. Gun Bore Panoramic Image Detection and Fusion%火炮内膛全景图像检测与融合

    Institute of Scientific and Technical Information of China (English)

    贾惠芹; 张茹

    2013-01-01

      火炮内膛检测是火炮使用维修过程中的一项重要内容,关系到火炮的射击精度和使用安全性。分析了通过自聚焦透镜阵列所获取的火炮内膛图像的特点,提出了一种基于相位相关法和对数极坐标法相结合的火炮内膛局部图像快速无缝拼接算法。相位相关法可以实现对存在平移的图像进行拼接,而不具有尺度和旋转不变性,对数极坐标法可将图像笛卡尔坐标系下的尺度和旋转变化变换为对数极坐标系的平移运动,利用该组合方法可得出归一化相位相关度的峰值,利用峰值点坐标可求得两幅相邻图像的旋转和缩放参数值,根据此参数进行多方位图像的拼接,然后采用像素最大值法得到内膛全景图像。实验结果表明,该方法可获得无缝、清晰和完整的火炮内膛图像。%The cannon chamber detection is an important task in the gun bore maintenance process, and it has direct relationship with the firing accuracy and security. The features of cannon chamber images obtained from grin lens array are analyzed, and an algorithm based on the phase-correlation and log polar is presented, which can realize mosaic image fast and seamlessly. Phase correlation algorithm can only match the images with shift invariability, and would face difficulty when dealing with motion model,where either scaling or rotation of the matched images is presented. Log-polar image transform can convert the scale and rotation changes in Descartes coordinate to shift changes in log-polar coordinate. This method calculates the normalized peak of phase correlation of cross-power spectrum, and gets the rotation and scale between the two conjoint images using the peak coordination. Images are matched based on these parameters, and then chamber panoramic images are obtained by using method of pixels maximum value. Experimental results show that the proposed method can get seamless, clear and full

  4. TK42200 NC Boring and Milling Machine to Increase Transformation Tool%TK42200数控镗铣床增加刀库的改造

    Institute of Scientific and Technical Information of China (English)

    范芳洪

    2014-01-01

    In order to solve the TK42200 NC boring and milling machine to realize the automatic tool change, will increase in Machine Tool Retrofit techniques applied to the NC machine tool function expan-sion. Analysis of the method to control the tool change, proposed by NC and PLC combined control method of tool change, design the fixed cycle and the PLC control program NC changer. After debugging tool li-brary transformation can reliably tool change, tool change and product processing of experiment, the experi-mental results show that:the tool changing high repeat precision, the product quality, reducing the labor in-tensity of operators, by modifying the system variables to repair tool table the knife has the advantages of simple operation.%为了解决TK42200数控镗铣床实现自动换刀的问题,将在机床上增加刀库的改造技术应用到数控机床功能扩展中。开展了换刀控制方法的分析,提出了NC和PLC相结合共同控制换刀的方法,设计了NC换刀固定循环程序和PLC控制程序。刀库改造调试后能够稳定可靠地换刀,进行换刀和产品加工的实验,实验结果表明:换刀重复精度高,产品质量合格,减轻了操作人员劳动强度,通过修改系统变量来修复刀具表使刀库操作简单了。

  5. New Technology of Segments Connected for Bored Pile Reinforcement Cage%灌注桩钢筋笼分段连接新技术

    Institute of Scientific and Technical Information of China (English)

    高振宁; 陈江涛

    2013-01-01

    介绍了北京地铁10号线亮马河站东南风道采用PBA工法施工,在小导洞内进行灌注桩施工过程中,因为场地条件不允许整体吊装钢筋笼,需要分段加工现场、吊装、组装;逐段连接时,传统的焊接技术速度慢、连接质量不稳定,工程中采用钢筋滚轧直螺纹接头进行快速连接的新技术,施工高效,质量可靠;成熟的工法和新技术相结合,往往会收到事半功倍的效果。%The ventilation drift located in southeast of Liangmahe station in Beijing Subway Line No. 10 was constructed by PBA construction method. On the construction process of bored pile in a small guide tunnel,the reinforcement cage can not be lifted totally because of the in-site conditions and need to be segmented, lifted and connected. The traditional welding technique for segments connection is slow and unstable. So the new technology of the steel rolling straight thread fittings for quick connecting was adopted and it had some advantages of construction efficiency and reliable quality. It will produce a multiplier effect on combining mature construction methods with new technology.

  6. Manufacturing of high precision bores

    NARCIS (Netherlands)

    Bana, I.V.

    2006-01-01

    Traditional finishing, like grinding, particularly in the machining of hardened parts, requires the consumption of a significant amount of coolant. This is harmful for the environment. Besides this, more initiatives were taken in process planning to improve the process economy and flexibility. Reduc

  7. Structural variation of solid core and thickness of porous shell of 1.7 μm core-shell silica particles on chromatographic performance: narrow bore columns.

    Science.gov (United States)

    Omamogho, Jesse O; Hanrahan, John P; Tobin, Joe; Glennon, Jeremy D

    2011-04-15

    Chromatographic and mass transfer kinetic properties of three narrow bore columns (2.1×50 mm) packed with new core-shell 1.7 μm EIROSHELL™-C(18) (EiS-C(18)) particles have been studied. The particles in each column varied in the solid-core to shell particle size ratio (ρ), of 0.59, 0.71 and 0.82, with a porous silica shell thickness of 350, 250 and 150 nm respectively. Scanning and transmission electron microscopy (SEM and TEM), Coulter counter analysis, gas pycnometry, nitrogen sorption analysis and inverse size exclusion chromatography (ISEC) elucidated the physical properties of these materials. The porosity measurement of the packed HILIC and C(18) modified phases provided the means to estimate the phase ratios of the three different shell columns (EiS-150-C(18), EiS-250-C(18) and EiS-350-C(18)). The dependence of the chromatographic performance to the volume fraction of the porous shell was observed for all three columns. The naphtho[2,3-a]pyrene retention factor of k'∼10 on the three EiS-C(18s) employed to obtain the height equivalents to theoretical plates (HETPs) data were achieved by varying the mobile phase compositions and applying the Wilke and Chang relationship to obtain a parallel reduced linear velocity. The Knox fit model gave the coefficient of the reduce HETPs for the three EiS-C(18s). The reduced plate height minimum h(min)=1.9 was achieved for the EiS-150-C(18) column, and generated an efficiency of over 350,000 N/m and h(min)=2.5 equivalent to an efficiency of 200,000 N/m for the EiS-350-C(18) column. The efficiency loss of the EiS-C18 column emanating from the system extra-column volume was discussed with respect to the porous shell thickness.

  8. Cutting system arrangement method of hard rock boring machine%硬岩掘进机破碎机构布置方法

    Institute of Scientific and Technical Information of China (English)

    毛君; 谢春雪; 梁晗; 黄华

    2013-01-01

      Hard rock roadheader is the key equipment in laneway constructions. In view of the traditional point-attack picks sever loss while breaking rocks, this paper put forward a shock and rolling breaking method which utilizes impact mechanism and a rolling mechanism to break rocks. This study analyzed the duration, the reliability and the driving efficiency on the cutter of the hard rock tunnel boring machine, and optimized the relations between the hard rock crushers using multi-disciplinary optimization method. In addition, this paper researched on factors that influence the layout of crushers which include global coordinating optimization as main factor, coordinating the optimization of parameters, the impact parameter, cutting force, cutting parameters and rock properties matching. The results of study show that the arrangement of the hard rock crusher was feasible, and it is optimal in energy consumption, tool wearing, driving efficiency and overall performance.%  针对传统镐齿破碎岩石的损耗严重,提出一种冲击滚压破碎方式。其结构采用冲击机构和滚压机构配合破碎岩石,考虑影响硬岩掘进机刀具的寿命、可靠性、掘进效率因素,采用多学科优化方法构建硬岩掘进机破碎机构布置关系,并以全局协调优化为主导,总体协调优化参数,对破碎机构的布置进行冲击参数、刀具受力、切削参数、围岩属性的匹配研究。研究结果表明:该硬岩掘进机破碎机构布置方法可行,降低了硬岩掘进机能量消耗、刀具的磨损,提高了掘进效率,使整机性能达到最优。

  9. Native and non-indigenous boring polychaetes in Chile: a threat to native and commercial mollusc species Poliquetos perforadores nativos y no indígenas en Chile: una amenaza para moluscos nativos y comerciales

    Directory of Open Access Journals (Sweden)

    RODRIGO A MORENO

    2006-06-01

    Full Text Available Boring polychaetes infesting the shells of aquacultured molluscs affect host fitness and cause serious economic problems for the aquaculture industry. In Chile, knowledge of the native and non-indigenous polychaete fauna associated with mollusc hosts is limited, in spite of the fact that numerous native and non-indigenous mollusc species are actively harvested. We present the first complete list of boring polychaete species present in Chile, with a review of the information regarding each species' status as a native or non-indigenous species (NIS, together with information on native and introduced ranges, affected host species, likely vectors of introduction and donor areas. We recorded a total of nine boring polychaetes present along the Chilean coast including native and NIS. Within the NIS category we provide the first published report of the Sabellid Terebrasabella heterouncinata in South America. Boring polychaetes utilized both native and introduced host species. The finding of polychaete species which utilized multiple native and NIS hosts, indicates a potential risk for spread between aquaculture facilities and the natural environment. Our analysis suggests that aquaculture activities are probably the primary introduction vector for boring polychaete species to Chile and that this region does not differ in the magnitude of introduced boring polychaetes relative to other regions of the world. We discuss current laws and management regarding polychaete infestations and make recommendations for future management in Chile, which should contemplate a rational compromise between the socio-economic needs of the country and plans to protect and preserve the nation's biodiversityLa colonización de especies de poliquetos perforadores sobre conchas de moluscos de cultivos puede afectar la adecuación biológica del hospedador y causar serios problemas económicos para la industria acuícola. En Chile, el conocimiento de la fauna de poliquetos

  10. Intra-arterial MR-angiography on an open-bore MR-scanner compared to digital-subtraction angiography of the infra-popliteal runoff in patients with peripheral arterial occlusive disease

    Energy Technology Data Exchange (ETDEWEB)

    Huegli, Rolf W. [Department of Radiology University Hospital of Basel, Petersgraben 4, 4031 Basel (Switzerland)], E-mail: rhuegli@uhbs.ch; Thalhammer, Christoph [Department of Angiology, University Hospital of Basel, Petersgraben 4, 4031 Basel (Switzerland)], E-mail: cthalhammer@uhbs.ch; Jacob, Augustinus L. [Department of Radiology University Hospital of Basel, Petersgraben 4, 4031 Basel (Switzerland)], E-mail: ajacob@uhbs.ch; Jaeger, Kurt [Department of Angiology, University Hospital of Basel, Petersgraben 4, 4031 Basel (Switzerland)], E-mail: kjaeger@uhbs.ch; Bilecen, Deniz [Department of Radiology University Hospital of Basel, Petersgraben 4, 4031 Basel (Switzerland)], E-mail: dbilecen@uhbs.ch

    2008-06-15

    Purpose: To evaluate the diagnostic value of contrast-enhanced intra-arterial 3D-MR-angiography (IA-MRA) of the infra-popliteal arteries in an open-bore magnet. Number, severity of arterial lesions, and artefacts were compared to routinely performed intra-arterial digital-subtraction angiography (IA-DSA) in patients suffering from symptomatic peripheral arterial occlusive disease (PAOD). Material and methods: Fifteen patients admitted for PAOD underwent percutaneous transluminal angioplasty (PTA) by IA-DSA. After PTA, IA-MRA of the infra-popliteal station was performed on an open-bore 1.5 T MR-scanner applying a low dose intra-arterial contrast-enhanced 3D-gradient-echo-MRA with gadopentate dimeglumine. The reading was performed by three blinded readers distinguishing moderate ({<=}50%), significant stenoses (51-99%) and vessel occlusions. Imaging artefacts were recorded and binary classified as not disturbing or compromising the observation of the arterial tree. Results: Overall IA-DSA revealed 36 moderate stenoses ({<=}50%), 38 significant stenoses (51-99%), and 10 vessel occlusions. For the detection of significant stenoses and occlusions, the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of IA-MRA were 96%, 83%, 88%, 94% and 90%. The only observed artefact was venous overlay in four stations. The readout was not hampered in any case. Conclusion: Intra-arterial contrast-enhanced 3D-gradient-echo-MRA on an open-bore MR-scanner offers an acceptable diagnostic accuracy in diagnosing peripheral arterial occlusive disease in the infra-popliteal region and correlates well with DSA.

  11. Mécanisme de l'usure par polissage des cylindres de moteurs diesel Bore Polishing Wear Mechanism in Diesel Engine Cylinders

    Directory of Open Access Journals (Sweden)

    Fayard J. C.

    2006-11-01

    particulier, l'usure des segments ainsi que les débits de gaz de soufflage, sont plus faibles qu'avec une chemise normale. Enfin, le mécanisme de l'usure par polissage par abrasion douce à deux et à trois corps est parfaitement confirmé par une exploration micrographique et une microanalyse des surfaces polies. A fast and economical method for evaluating lubricants and fuels in relation to the bore polishing wear of super charged diesel-engine cylinders has been developed using a single-cylinder laboratory engine within the framework of an Société Nationale Elf Aquitaine - Institut Français du Pétrole (SNEA-lFP research agreement. This method bears the reference IFP-UP-4/80.It also serves to evaluate the deposit-forming and sticking tendency, ring wear and the oil-consumption tendency of lubricants. It is in good correlation with the CEC-Ford Tornado test and makes an excellent discrimination between the Coordinating European Council (CEC reference cils RL 47 and RL 48. The method is used for investigating the bore polishingwear mechanism by searching for the influence exerted by the principal parameters: (a Composition of the lubricant: the phenomenon is influenced by the base oil and its viscosity, by the amount of polymers improving the viscosity index and especially by the choice of detergent additives. As a first approximation and for homogeneous oil familles, polishing wear increases when the thermal stability of the oil decreases. (b Engine running: polishing increases very fart with the engine load after a certain threshold, and its evolution in time as observed by endoscopic rating shows a characteristic S shape as polishing begins on the thrust side and at the top of the cylinder. (c Composition of the fuel: the increase in the sulfur content of diesel fuel considerably decreases polishing wear caused by an oil reputed to be poorfrom this standpoint but has no effect on a goodoil. (d Surface finish of the cylinder: prepolishing the liner by extremely fine

  12. The Influence of Plateau Honing Process Parameters on Cylinder Bore Surface Roughness%平台珩磨加工参数对缸孔表面粗糙度的影响

    Institute of Scientific and Technical Information of China (English)

    王晓骎; 马戎; 张雪萍; 姚振强

    2015-01-01

    平台珩磨是目前被广泛应用的一种发动机缸孔精加工工艺,珩磨后缸孔的表面粗糙度直接影响缸孔的摩擦磨损性能.针对某型发动机缸孔的平台珩磨工艺,采用正交试验的方法研究平台珩磨转速、粗珩进给率、精珩时间对缸孔表面粗糙度的Abbott参数(波峰平均高度Rpk、波谷平均深度Rvk)和加工效率的影响规律.研究结果表明:珩磨转速对Rpk 、Rvk的影响最大,其次为精珩时间,粗珩进给率对其影响很小;而通过提高粗珩进给率,能够在不显著改变缸孔表面粗糙度的条件下,大幅度提升平台珩磨加工效率.%Plateau honing is a widely used method for the finishing of engine cylinder bores.Plateau honing forms the surface topography of cylinder bore which has a direct effect on the engine friction and wear performance.The influence of plateau honing process parameters (honing rotation speed,rough honing expansion speed,finish honing duration) on cylinder bore surface roughness parameters(peak roughness Rpk,valley roughness Rvk) and plateau honing efficiency is studied by means of orthogonal experiments.The result shows that honing rotation speed is the most principal influence factor on Rpk and Rvk;finish honing duration is the second most principal factor,and rough honing expansion speed does not have major influence on Rpk and Rvk.Plateau honing efficiency could be improved by increasing rough honing expansion speed without significantly changing the surface roughness of cylinder bores.

  13. Predictive power of the ESUR scoring system for prostate cancer diagnosis verified with targeted MR-guided in-bore biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Schimmöller, L., E-mail: Lars.Schimmoeller@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Quentin, M., E-mail: Michael.Quentin@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Arsov, C., E-mail: Cristian.Arsov@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Urology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Hiester, A., E-mail: Andreas.Hiester@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Urology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Kröpil, P., E-mail: Patric.Kroepil@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Rabenalt, R., E-mail: Robert.Rabenalt@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Urology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Albers, P., E-mail: urologie@uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Urology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Antoch, G., E-mail: Antoch@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany); Blondin, D., E-mail: Dirk.Blondin@sk-mg.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Moorenstr. 5, D-40225 Dusseldorf (Germany)

    2014-12-15

    Highlights: • The PI-RADS summed score (PS{sub sum}) demonstrated very good diagnostic values, especially for higher grade PCa. • Lesions with PS{sub sum} ≥13 represented prostate cancer in 88% and higher grade prostate cancer in 42%. • Sensitivity and NPV was nearly 100% for higher grade PCa detection using a cut-off limit of PS{sub sum} 10. • Peripheral zone lesions demonstrated better diagnostic value with the PS{sub sum} compared to transitional zone lesions. • Further improvement of the PI-RADS score is required to prevent unnecessary overdiagnosis. - Abstract: Purpose: This study evaluates the diagnostic value of the ESUR scoring system (PI-RADS) regarding prostate cancer detection using MR-guided in-bore biopsies (IB-GB) as the reference standard. Methods: 566 lesions in 235 consecutive patients (65.7 ± 7.9 years, PSA 9.9 ± 8.5 ng/ml) with a multiparametric (mp)-MRI (T2WI, DWI, DCE) of the prostate at 3 T were scored using the PI-RADS scoring system. PI-RADS single (PS{sub single}), summed (PS{sub sum}), and overall (PS{sub overall}) scores were determined. All lesions were histologically verified by IB-GB. Results: Lesions with a PS{sub sum} below 9 contained no prostate cancer (PCa) with Gleason score (GS) ≥ 4 + 3 = 7. A PS{sub sum} of 13–15 (PS{sub overall} V) resulted in 87.8% (n = 108) in PCa and in 42.3% (n = 52) in GS ≥ 4 + 3 = 7. Transition zone (TZ) lesions with a PS{sub sum} of 13–15 (PS{sub overall} V) resulted in 76.3% (n = 36) in PCa and in 26.3% (n = 10) in GS ≥ 4 + 3 = 7, whereas for peripheral zone (PZ) lesions cancer detection rate at this score was 92.9% (n = 79) and 49.4% (n = 42) for GS ≥ 4 + 3 = 7. Using a threshold of PS{sub sum} ≥ 10, sensitivity was 86.0%, and negative predictive value (NPV) was 86.2%. For higher grade PCa sensitivity was 98.6%, and NPV was 99.5%. Conclusion: A PS{sub sum} below 9 excluded a higher grade PCa, whereas lesions with a PS{sub sum} ≥ 13 (PS{sub overall} V) represented in 88

  14. 大直径钻孔灌注桩的竖向承载性能%Vertical bearing capacity of large-diameter bored pile

    Institute of Scientific and Technical Information of China (English)

    刘念武; 龚晓南; 俞峰

    2015-01-01

    T he self‐balancing test w as conducted on tw o 2 .2 m diameter drilled piles in order to analyze the bearing capacity of large diameter bored piles .The test results were compared with in‐situ test results . Results show that the change of load‐displacement of pile with post‐grouting is slower than pile without post‐grouting .The end resistance reached the limit state when pile tip displacements approached 20 mm (1% D ,D is the pile diameter) .The side resistance increased firstly and maintained a stable trend with the increase of pile‐soil relative displacement .The critical displacement was 1 .5‐3 .0 mm .Post‐grouting can improve the side resistance over a certain depth from the pile tip ,and the improvement in round gravel mixed pebble bed is 18 percent . Resistive loads up and dow n the side of the load cell is different and transformation coefficient is 0 .92 and 0 .91 , respectively . Side resistance and undrained vane‐shear strength has a linear relationship and has a better goodness of fit .The ultimate side resistance of round gravel mixed can be estimated by dynamic sounding (63 .5 kg) hits .%为了分析大直径钻孔灌注桩的承载性能,对2根直径分别为2.2m的钻孔灌注桩开展自平衡试验,将试验结果与原位测试结果进行对比分析.通过对测试结果的分析发现,注浆后荷载箱的向上及向下荷载‐位移曲线的变化更加缓慢,当桩端位移为20 mm(1% D ,其中 D为桩径)左右时,端阻达到极限状态,未注浆桩和注浆桩的极限端阻分别为2834、3561 kPa .桩身侧阻随着桩土相对位移的增大呈先增大后保持稳定的趋势,淤泥质粉土层、黏土夹粉砂层、圆砾混卵石层的侧阻在桩土相对位移为1.5~3.0mm时达到稳定.注浆能够提高桩端以上一定深度的桩身侧阻,圆砾混卵石层中侧阻的提高幅度约为18%.荷载箱上下的侧阻随位移的变化模式不同,未注浆桩

  15. 利用反井钻机施工组合煤仓%Application of Raise Boring Machine to Construction of Combined Coal Bunker

    Institute of Scientific and Technical Information of China (English)

    刘国申

    2014-01-01

    A middle coal bunker in Ji4 Mining Block of No.5 Mine in Pingdingshan Tian’an Coal Com pany Limited was a combined coal bunker with a vertical bunker and a high inclined bunker. A de signed depth of the vertical bunker was 42.5m. The vertical bunker was a round cross section. The net diameter of the vertical bunker was 4m and the excavation diameter was 4.8m. A designed length of the inclined bunker was 23.1m with an inclination of 65° and the bunker was a round cross section with a net diameter of 3m and excavation diameter of 3.8m. In the constructions of the vertical bunker and the inclined bunker,a raise boring machine was first applied to the pilot drilling and to the pilot borehole reaming. Then a conventional drilling and blasting method was applied to the reaming of the bunker. A bolt and steel mesh was applied to the temporary support of the bunker,a reinforced con crete was applied to the permanent support of the bunker and the short section excavation and lining method was applied. A total construction period of the combined coal bunker was 85 days,the con struction mission was completed on schedule,the project quality was excellent and a good evaluation was made by the project owner.%平顶山天安煤业股份有限公司五矿己四采区中部煤仓,是由立仓和大倾角斜仓构成的组合煤仓。立仓设计深度42•5m ,圆形断面,净直径4m ,荒径4•8m。斜仓设计长度23•1m ,倾角65°,仓身亦为圆形断面,净直径3m ,荒径3•8m。立仓和斜仓施工中,均先利用反井钻机进行导孔和扩孔钻进,形成反井井孔;再用普通钻爆法刷大,锚网临时支护,钢筋混凝土永久支护,短段掘砌。该组合煤仓实际总工期为85d ,按期完成了施工任务,工程质量优良,受到了业主好评。

  16. Construction Techniques for the Treatment of the Collapse of Bored Holes for Large-Diameter Foundation Piles%大直径基桩坍孔处理施工技术

    Institute of Scientific and Technical Information of China (English)

    尤春颖

    2011-01-01

    新月铁路分离式立交桥21-1基桩紧邻电气化铁路,振动较大且砂土层较厚,在试桩过程中发生坍孔。分析工程具体情况,决定采用预制钢筋混凝土沉井护壁处理。介绍了沉井的设计、加工与下沉,大直径冲击钻成孔过程及相应的质量控制措施,处理后的基桩质量良好。可为类似工程处理提供有益借鉴。%Owing to the fact that the No. 21-1 foundation pile of the Xinyue Railway Separate Overpass is near an electrified railway, where the vibration is very strong and the sand layer is thick, the wall of the bored hole collapsed in the course of test-boring

  17. Pile anchor Supporting System Combined with Priestesses Anchor Cables and Bored Piles%预应力锚索与钻孔咬合桩相结合的桩锚支护体系*

    Institute of Scientific and Technical Information of China (English)

    褚锡星; 殷建

    2013-01-01

    预应力锚索与钻孔咬合桩结合的桩锚支护体系能有效的降低排桩间漏水,减少搭设和拆除深基坑内支撑工程成本,拓宽机械工作面,确保工程工期,避免角撑、对撑施工。通过具体工程案例,系统论述了预应力锚索与钻孔咬合桩结合的桩锚支护体系工艺流程、施工要点及其监测方法,为其在工程中的应用提供理论支撑。%The pile anchor supporting structure combined with prestressed anchor cables and bored piles can effectively reduce water leakage between rowed piles and the cost of erecting and dismantling supporting engineering in deep foundation pits.It can also,expand mechanical working surface,ensure project schedule and avoid gusset and supporting construction.The paper analyses the technological process,key points of construction and monitoring methods of the pile anchor supporting structure combined with prestressed anchor cables bored piles, so as to provide theoretical support for its application in engineering.

  18. Honing Trajectory Reconstruction and Accuaacy Control for Automotive Engine Cylinder Bore%汽车发动机缸孔珩磨轨迹重构与精度控制

    Institute of Scientific and Technical Information of China (English)

    高罗辉; 张雪萍; 姚振强

    2013-01-01

    This paper ascertains the relationship between the honing head's rotation angle in circumferential direction of the cylinder bore and motion parameters through the analysis and reconstruction of the honing abrasive trajectory. The motion parameters include rotational speed, reciprocating velocity, bottom stroke delays time, and up and down overshoot length. Thus the distribution of the abrasive trajectory is obtained. Based on the research, the paper establishes the corresponding relationship between the honing head motion parameters and the distribution of abrasive trajectory. Finally through the control of abrasive trajectory distribution, it provides a method to improve the cylinder bore honing accuracy.%通过对汽车发动机缸孔珩磨头的运动轨迹的跟踪分析与重构,确定了珩磨头旋转速度、往复运动速度、下端停留时间、上下越程等主要运动参数的变化对珩磨头周向相位角的影响规律,重构磨粒运动轨迹轮廓,建立珩磨关运动参数与磨粒轨迹分布的映射关系模型.基于该模型,探索了控制珩磨轨迹分布的均匀性的看法,改善了缸孔珩磨精度.

  19. 复杂轮系在镗孔车端面装置中的应用%The Application of Complicated Gear train in The Device of Boring Holes and Turning End Face

    Institute of Scientific and Technical Information of China (English)

    刘萍

    2014-01-01

    Researchthe application of complicated gear train in the device of boring holes and turning end face.Analysis the parallel compound gear train consisting of planetary gear train and differential gear train,and the series hybrid gear train consisting of planetary gear train,fixed axis gear train and the parallel compound gear train.The feed movement and the feed amount of the device is discussed,at the stage of rough and finish machining,quick returning.And the application principle of the boring holes and turning end face is clarified.%本文研究复杂轮系在镗孔车端面装置中应用,分析行星轮系与差动轮系构成的并联复合轮系,行星轮系和定轴轮系组成的串联混合轮系,探讨了孔车端面装置在粗、精加工及快退时进给运动和进给量等,阐明镗孔车端面装置的应用原理。

  20. The Process Method of Manufacturing Long Holes in the Indexing Surface with Ordinary Boring Machine%用普通镗床加工分度曲面长孔的工艺方法

    Institute of Scientific and Technical Information of China (English)

    秦根喜; 秦超

    2013-01-01

    利用普通数显130/2镗铣床,将数字技术与普通技能相结合,计算节点、角度、角度偏移、数显表的内置分度圆功能;将刀位点坐标移位的进刀方法和小背吃刀量、高转速、大进给的工艺方法相结合,加工分度曲面长孔,实现了利用普通机床加工分度曲面长孔的技术创新.%By using ordinary boring machines 130/2 with digital displaying, combinedg digital technology with general skills, the node,angle,angle offset and the built-in reference circle of the digital display table were calculated. If the feed method of the coordinate displacement for the cutter location and small back engagement,high speed,the process method of roughing feed can be got together to process long holes in the indexing surface. It will realize technological innovation of manufacturing long holes in the indexing surface with ordinary boring machine.

  1. 钻孔灌注桩用于公路软土地基施工研究%Bored piles used in the study of highway construction in soft soil

    Institute of Scientific and Technical Information of China (English)

    崔玉庆

    2015-01-01

    软土地基是公路施工常见通病,因软土层结构具有明显的脆弱性,对公路结构性能产生诸多功能性危害。新时期公路施工技术实现了优化转变,采用钻孔灌注桩处理软土地基问题取得良好效果,为公路现代化建设提供技术支撑。结合软土地基特点及其危害性,分析了软土路段公路主要病害形式,提出钻孔灌注桩用于软土地基处理的工艺方案。%Soft soil foundation in highway construction is the common disease, because of the soft soil layer structure has obvious vulnerability, many functional damage of highway structure performance. Optimization of highway construction technology to achieve the transformation in the new period, dealing with soft soil foundation using bored piles obtain good effect, provide technical support for the modernization of highway construction. Combining with the characteristics of soft soil foundation and its harmfulness, analyzes the main forms of these diseases, and soft soil road highway bored piles is put forward for the processing plan of soft soil foundation treatment.

  2. 吕梁山林区油松蛀干害虫危害及风险性分析%Hazard and Risk Analysis on Trunk Boring Pests of Pinus tabulaeformis in Lvliang Mountain ’s Forest Area

    Institute of Scientific and Technical Information of China (English)

    程志枫

    2015-01-01

    吕梁山林区蛀干害虫主要有红脂大小蠹(Dendroctonus valens LeConte)、松幽天牛(Asemum amurense Kraatz)两种。采用人工诱捕和引诱剂诱捕的办法,对吕梁山国有林管理局16个有林单位进行了调查,摸清了蛀干害虫的种类及其分布、危害情况,并对有害生物松幽天牛进行了风险性分析评估,指出其评估值R=1.68,属于中度危险性林业有害生物,应加强防范与管理。%The trunk boring pests in Lvliang montain’s forest area are mainly Dendroctonus valens LeConte and Asemum amurense Kraaatz. By using the artificial trap and attractants trap, this paper carries out an investigation on 16 units covered by forests under Lvliang Mountain State-owned Forest Administration, finds out the species of the trunk boring pests and their distribution and harm condition, and conducts a risk analysis and evaluation on Asemum amurense Kraaatz, and points out that its evaluation value R of which is 1.68, belongs to moderate dangerous forest pest, should strengthen the prevention and management of it.

  3. 大型数控落地镗铣床滑枕静压导轨的分析与研究%Analysis and Research of Ram Hydrostatic Guideway for Large NC Floor Type Boring and Milling Machine

    Institute of Scientific and Technical Information of China (English)

    华小龙; 郭旭红; 潘贤兵

    2014-01-01

    分析了大型落地镗铣床使用静压导轨的原因,介绍了静压导轨的分类和特点,并对滑枕静压导轨的参数进行了计算。通过在大型落地镗铣床上应用静压导轨技术,使得大型落地镗铣床的动态特性好、抗振性强、运动精度高,大大提高了工件的加工精度。%The cause of using hydrostatic guideway in large floor type boring and milling machine was analyzed.The classifica-tion and characteristics of hydrostatic guideway were introduced,and also the parameters of ram hydrostatic guideway were calculated. Through the application of technology of hydrostatic guideway in large floor type boring and milling machine,the dynamic characteris-tics of the machine was good,and it also had the strong vibration resistance and high motion precision.The processing precision of the workpiece is improved greatly.

  4. Analysis of Two Momentum Calculation Methods for Recoiling Parts During Projectile Motion in Bore%膛内时期后坐部分两种动量计算方法分析

    Institute of Scientific and Technical Information of China (English)

    魏浩; 于存贵; 崔二巍

    2015-01-01

    研究对火炮动力学性能设计方法的优化,准确的设计方法对火炮系统的研究具有很重要的意义。现行的火炮后坐部分膛内时期动量计算方法得到的结果与火炮试验中得到的数据存在很大差异。为提高计算的准确性,对现行计算方法进行优化,提出了一种新的后坐部分动量计算方法。为验证新方法的优越性,建立基于弹炮耦合的某舰炮后坐部分模型,利用ABAQUS有限元分析软件对该舰炮后坐部分膛内运动时期进行仿真分析。结果表明,新方法与仿真结果吻合度较高。数值仿真结果可以为相关研究提供参考。%To study the optimization of artillery dynamic performance design method,Accurate design method of the study of gun system has very important significance. The momentum data for recoiling parts during the projectile motion in the bore,which is obtained by a artillery test ,have obvious difference compared with the calculated results.In order to improve the accuracy of the calculation,and optimize the current calculation method,this paper proposes a new took some momentum calculation method. In order to verify the superiority of new method,a projectile-barrel coupling model for a certain naval gun has been set up and the simulation analysis for the movement during the projectile motion in the bore has been carried on through ABAQUS. The simulation results show that the new method on momentum calculation for the recoiling parts during the projectile motion in the bore is accurate. Besides above,the results can provide a reference for correlation study.

  5. 谈公路桥梁工程施工中钻孔灌注桩技术的应用%Discussion on the application bored pile technology in highway bridge engineering construction

    Institute of Scientific and Technical Information of China (English)

    董慧勇

    2015-01-01

    对公路桥梁工程施工中钻孔灌注桩技术进行了介绍,并对钻孔灌注桩施工中测量放线、安装钻孔机、造浆工作、制作钢筋笼等工艺进行了分析,探讨了各工艺环节的施工要求,提出了相应的技术管理措施。%The thesis introduces bored pile technology in highway bridge engineering construction,analyzes its measurement sampling,installa-tion driller,slurry manufacture and steel cage manufacture and other techniques,explores its construction demands,and finally puts forward cor-responding technology management measures.

  6. 数控铣镗床头库附件头自动更换管理软件开发设计%Design and development on AAC control software of multilayer head magazine for CNC milling-boring machine

    Institute of Scientific and Technical Information of China (English)

    刘志兵; 孙志强

    2011-01-01

    以数控落地铣镗床头库附件头自动更换,配备西门子840D数控系统为例,介绍了基于CNC和PLC控制程序,并融合了用户变量、用户宏变量指令及DRP双口RAM数据交换等功能的,一种开发设计机床功能控制软件的方法,供参考.%Taking AAC control software of CNC floor type milling-boring machine with multilayer head magazine and Siemens 840D for example. Introducing a design and development measure on the application of technique of CNC and PLC programming, combining with the functions sach as UGDB, UMAC and DRP data exchange.

  7. Pile-soil interface shear model of super long bored pile and its FEM simulation%超长灌注桩桩-土界面剪切模型及其有限元模拟

    Institute of Scientific and Technical Information of China (English)

    王卫东; 李永辉; 吴江斌

    2012-01-01

    Super long bored piles are friction piles; thus establishing the appropriate pile-soil interface shear model is the key to reasonable and effective simulation analyze the load-movement characteristics of the pile. According to working trait of the super long bored pile shaft friction (r) with the increasing of pile-soil relative movement (w),ι-w relationships are divided into the hardening and the softening types. Furthermore, the mobilized patterns of the pile shaft friction are divided into three types: the full hardening mobilized pattern, full softening mobilized pattern and hardening-softening mixed mobilized pattern. Hardening type and softening type pile-soil interface shear models are established for super long bored pile. The pile-soil interface shear models are introduced into FEM software using subroutine FRIC of ABAQUS. Single pile simulation example shows that the interface shear models are implemented in ABAQUS successfully. FEM simulation of field test piles is carried out using the established pile-soil interface shear models. The simulation results are similar to the measured results. It is shown that the established pile-soil interface shear models and FEM simulation have the rationality and feasibility to calculate the load-movement behavior of super long bored pile.%由于超长灌注桩为摩擦型桩,建立合适的桩-土界面剪切模型将成为合理且有效地模拟分析其承载变形特性的关键.基于超长灌注桩桩侧摩阻力τ随桩-土相对位移w发挥性状,将τ-W关系定义为硬化和软化两种类型,进而将桩侧摩阻力发挥模式分为全硬化模式、全软化模式和混合模式.建立超长灌注桩桩-土界面剪切硬化模型和软化模型,运用ABAQUS二次开发子程序FRIC将建立的剪切模型嵌入有限元,实现剪切模型的有限元模拟,单桩算例表明,剪切模型在ABAQUS中实现是成功的.运用建立的桩-土界面剪切模型对现场试验试桩进行有限元模拟,

  8. The Effects of Horn-Shaped Sound Bores on the Acoustic Characteristics of Earmolds%号角状声孔对耳模声学特性的影响

    Institute of Scientific and Technical Information of China (English)

    胡旭君; 庞珞

    2011-01-01

    目的 研究不同规格号角状声孔对耳模声学特性的影响,寻找出在我国正常成人耳发挥最大号角效应时,号角状声孔的出口段直径与长度值,为制作号角状声孔的耳模提供参考数据.方法 选取5名耳道较直较大成年受试者,为每例对象分别制作常规直径为2 mm声管的耳模一只,出口段长度为11 mm,直径分别为3、4、5mm的号角状声孔耳模三只,出口段直径为4 mm,出口段长度分别为8、11、14 mm的号角状声孔耳模三只,对每例受试者分别测试7种不同规格声孔耳模的真耳插入响应值,对结果进行比较,寻找号角效应达到最大时的出口段直径与长度的规格.结果 号角状声孔的最佳规格为出口段直径为2、3、4 mm,出口段长度为11 mm,此规格能很好地补偿高频插入损失.结论 通过合理设计号角状声孔耳模的参数,可以改变助听器输出的频响特性,改变助听器的频宽、增加高频增益,这为助听器参数的灵活设置提供了一种可选方案,可以更好地满足听障患者的需求.%Objective Through this experiment, we can obtain in the production of the horn-shaped sound bore earmolds from normal adult ears. When the horns effects achieve the best , the diameters and lengths of the export segment play the best role in altering acoustic characteristics. It is to provide the corresponding reference values for general patients. Methods For different sizes of horn- shaped sound bores it is important to obtain their real ear insertion responses to find the most appropriate effects from the provided diameter and length specifications of the export segment. Results Obtained the best specifications of the Horn-shaped sound bore was 2,3,4 mm of the export segment, 11 mm of the export length,this specifications had a better compensation for high-frequency insertion loss. Conclusion It is found that the best specifications for the horn-shaped sound bore is 2,3,and 4mm of the export

  9. 采用浮镗与滚压相结合的工艺加工油缸内孔%Processing Internal Holes of Oil Cylinders through Combined Floating Boring and Rolling Press

    Institute of Scientific and Technical Information of China (English)

    徐世韬; 李炫; 周聪

    2013-01-01

    In view of the problems that occur in the process of drilling internal oils of oil cylinders, a dedicated wide knife-based turning process is used instead of floating boring, with a rolling head for further processing, detailizing the process, making oil cylinder processing easier and more convenient, contributing to reliable quality and high processing efficiency.%  针对油缸内孔加工过程中出现的问题,设计了专用宽刀进行车削加工以代替浮镗加工,并采用滚压头对油缸内孔再次加工,细化了加工工艺,使油缸加工更加方便,质量可靠,加工效率高。

  10. Analysis on Common Accidents in Bored Piling Works and Responding Measures%在钻孔灌注桩施工中常见工程事故分析及处理方法

    Institute of Scientific and Technical Information of China (English)

    韩朝; 胡胜华; 谭靖

    2014-01-01

    钻孔灌注桩在目前较为普逗,其实该工艺技术含量较高,在施工中稍有不慎就会出现工程事故,本文结合以前的施工经验,对施工中容易出现事故的原因,从施工工序的角度加以全面的分析,并提出简便易行的处理方法。%Bored piling works are frequently seen at present. As a matter of fact, such a technique requires high level of technological prowess, thus making engineering-related accidents happen easily at construction sites. Based on previous construction experience, this paper tries to analyze reasons for engineering-related accidents from the perspective of construction procedures as well as propose feasible responding measures.

  11. Transformation of TPX619 Horizontal Digital Boring Electrical Control System on PLC%TPX619卧式数显镗床电气控制系统的PLC改造

    Institute of Scientific and Technical Information of China (English)

    李翠翠; 龙斌

    2013-01-01

    Using PLC to reform the TPX619 horizontal digital display boring machine, giving the new electrical control circuit and program design of ladder diagram in the paper. The machine with new control system works stably,with less breakdown and higher efficiency.%)采用可编程控制器(PLC)对TPX619卧式数显镗床的电气控制系统进行改造,给出了改造后的电气控制电路及程序设计梯形图,改造后机床运行稳定,降低了故障率,提高了生产效率。

  12. 后注浆灌注桩在某工程中的应用及经济分析%Application and Economic Analysis of Post-grouting Bored Concrete Pile in a Project

    Institute of Scientific and Technical Information of China (English)

    刘军; 洪峰

    2011-01-01

    Combined with the actual construction the principle and application of post-pressure grouting technology in pile tip and pile lateral of reinforced concrete bored cast-in pilate piles are introduced.There are many factors affecting pile foundation selection for construction works.Through the cost analysis and evaluation on the pile foundation of the construction works, some economic indicators for the selection of pile foundation under the present productive force and price level are gained.Which will be beneficial to improve the cost effectiveness and rationality of selection of it.The base-grouting treatment technique of bored concrete pile can improve the bearing capacity, so the application of this kind of pile become broad useage day by day.%结合工程实例,介绍了钢筋混凝土钻孔灌注桩桩端桩侧后压浆技术的原理及应用。影响建筑工程桩基选型的因素很多,通过典型工程桩基的造价分析与评价,得出当前生产力和物价水平条件下桩基选型的若干经济指标.有助于提高建筑工程桩基选型的经济性及合理性水平。由于灌注桩后注浆处理技术可使承载力显著提高.因而这种桩基日益得到广泛应用。

  13. Research on automatic boring-milling machine control system based on touch screen and PLC%基于触摸屏与PLC的自动镗铣床控制系统研究

    Institute of Scientific and Technical Information of China (English)

    齐凤莲; 陈晓男; 赵民; 许丽娟; 雷东亮

    2012-01-01

    In this paper, we take the work principle of a boring-milling machine as the research object. Proposing a combination of PLC and touch screen for improving ordinary boring-milling machine control system. Designing a multi-window man-machine interface which is made by a touch screen. In its existing control panel operation, we added a new touch screen operation mode which machine operation and monitoring are more intuitive and convenient. This paper mainly introduces the PLC-touch screen control system principle and structure design of touch screen. Project example shows that the proposed scheme realizes various operation modes of machine tools and provides a touch screen monitoring method with low cost, and are practical.%以镗铣床的工作原理为研究对象,将PLC与触摸屏相结合,对普通镗铣床控制系统进行改进,并以触摸屏为人机界面,设计出多窗口操作画面.从而在保留原有控制面板操作的基础上增加了触摸屏的操作方式,使机床的操作和监控更为直观和方便.着重介绍了PLC-触摸屏控制系统的结构原理和触摸屏画面的设计.工程实例证明,该方案通过较低的成本实现了机床的多种操作方式和提供了触摸屏的监控方法,具有很强的可实施性.

  14. 坡膛结构变化对火炮内弹道性能影响的研究%Study on Influence of Bore Structure on Gun's Interior Ballistic Performances

    Institute of Scientific and Technical Information of China (English)

    孙河洋; 马吉胜; 李伟; 生龙波; 吴大林; 刘海平

    2012-01-01

    Considered the coupling effects of classical interior ballistic equations and band' s engraving process, the solution of interior ballistic equations was taken as the boundary condition of the simulation for engraving process, and the results of the simulation were taken as (he initial conditions for the interior ballistic equations in the next step iteratively. A coupled constitutive model considered visco-plasticity and ductile damage and based on continuum damage mechanics was introduced to simulate the band' s damage process. The Von Mises yield criterion, Johnson-Cook hardening model and Johnson-Cook fracture strain model were adopted, and the model considered large strain, high strain-rate, thermal softening and damage evolution. The model was implemented in the explicit finite element code by using VUMAT subroutine of Abaqus\\Explicit module. The band' s engraving processes of two different bore structures were simulated, and the influences of different engraving conditions on the stress state of the band were analyzed. The effects of band' s stress state and bore structure on the interior ballistic performances were pointed out. It is very useful for the design of bore structure.%考虑了经典内弹道方程组和弹带挤进过程的耦合效应,以内弹道方程组的解作为弹带挤进过程数值模拟的力边界条件,同时以数值模拟的结果作为内弹道方程组下一增量步计算的初始条件.引入了Lemaitre提出的基于连续损伤介质力学的考虑粘塑性及韧性损伤耦合效应的本构模型来模拟弹带材料的损伤失效过程,采用了Von Mises屈服准则、Johnson-Cook硬化模型及Johnson-Cook失效模型,考虑了大应变、高应变率、温度软化作用、初始损伤及累计损伤失效效应,并借助一种高效的时间积分方法通过Abaqus\Explicit模块的材料子程序接口VUMAT将其引入到显式非线性有限元软件中,借助显式非线性有限元算法对两种坡膛结构

  15. Study on migration characteristic of boring mud in roadway floor anchor wire hole and its field test%巷道底板锚索孔钻进粉渣运移特征及现场试验

    Institute of Scientific and Technical Information of China (English)

    张辉; 程利兴; 常建超

    2015-01-01

    针对煤矿巷道底板锚索孔钻进困难的问题,分析了正反循环钻进过程中粉渣运移特征,得出“钻渣三区”的相互作用是制约底板锚索孔快速钻进的根本原因,并提出了泵吸反循环钻进可以有效防止“钻渣三区”的形成。利用固液流体力学原理,推导了冲洗液沿程水力损失及钻渣液上返流速的力学公式。根据现场实际,得出底板锚索孔泵吸反循环钻进时钻孔深度、泵的真空度及钻渣液的上返速度与钻渣体积含量之间的关系,结果表明泵吸反循环对底板锚索孔的快速钻进是可行的。研制了一套泵吸反循环钻进系统,实现了底板锚索孔钻进与排渣同时作业。现场试验表明,钻进深度5.6 m的底板锚索孔有效钻进时间可以控制在30 min内,解决了底板锚索孔深孔钻进的难题,净化了作业环境。%To solve the problem of drilling anchor holes into the roadway floor, migration characteris-tics of the reverse circulation drilling process of boring mud have been analyzed. The analysis has shown that the interaction of boring mud three-field is the primary cause of restricting floor anchor wire hole quickly drilling, and pump suction reverse circulation drilling that can be effectively prevented by boring mud three-field forming has been put forward. Using principles of solid-liquid fluid mechanics, mechanical formula of flushing fluid along hydraulic loss and slag drilling fluid return velocity has been successfully deduced. According to the field practice, the relationship between floor anchor wire hole pump suction reverse circulation drilling depth and drilling pump on vacuum degree and slag drilling fluid return velocity, and drilling slag volume content has been obtained. The result has shown that pump suction reverse circulation faster penetration of floor anchor hole is feasible. A set of pump suc-tion reverse circulation drilling system has been developed, and

  16. Wigner高阶谱在弹丸膛内运动分析中的应用%Application of Wigner Higher-order Spectra in Analysis of Projectile Motion in Bore

    Institute of Scientific and Technical Information of China (English)

    陈曦; 许建中

    2012-01-01

    针对传统时频分布分析的时频分布图能量聚集性差、交叉项干扰严重且对噪声敏感的问题,提出了一种基于Wigner高阶谱的膛内运动弹丸回波信号处理方法.对仿真信号从能量聚集性、交叉项抑制、抗噪声三个方面进行比较研究,结果表明Wigner高阶谱进行高阶多项式调频信号瞬时频率估计具有优势.对某型炮弹实测数据采用基于MATLAB的Wigner三谱对角切片算法获得时频分布图.提取时频分布图的时频脊线得到瞬时频率曲线.由多普勒效应公式反演出膛内弹丸的速度、加速度曲线.与实验结果相比:炮口速度相对误差为1.34%,弹丸运动距离与炮管实长的相对误差各为0.52%.验证了在强噪声环境下,Wigner高阶谱分析是膛内运动弹丸回波信号处理的一种更准确有效的方法.%In view of the problems of the time-frequency distribution map of traditional time-frequency distribution analysis that has poor convergence of energy, serious cross-term interference and noise sensitivity , a method for the signal processing of the echo of projectile motion in bore is proposed based on Wigner higher-order spectrum. The advantages of Wigner higher-order spectrum on the instantaneous frequency estimation of higher-order polynomial frequency modulation signals are verified through the comparative study of energy concentration, cross-term suppression and anti-noise. The time-frequency distribution map is obtained by the Wigner trispectrum slice spectrum algorithm designed on MATLAB for the measured data of a certain type of projectile. An instantaneous frequency curve is obtained through the ridge extraction of time-frequency distribution map. The velocity and acceleration curves of in-bore projectiles are inversed according to the Doppler effect formula. Compared with the experimental results,the relative errors of the muzzle velocity,the range of projectile motion and the real length of the barrel are

  17. Analysis of railgun in-bore magnetic field distribution at zero speed%静止条件下轨道炮膛内磁场分布特性分析

    Institute of Scientific and Technical Information of China (English)

    殷强; 张合; 李豪杰; 史云雷

    2016-01-01

    为了分析轨道炮静止条件下膛内磁场分布特性,建立了轨道炮二维计算模型,基于磁扩散方程与安培定律,得到导轨和电枢各区域电流密度值,并通过毕奥-萨伐尔定律对轨道炮电枢前端各考察点磁通密度进行理论计算,基于电磁感应法进行了膛内磁场测量实验,实验测量值与理论计算值基本一致,结果表明,膛内磁场大小主要由流经电枢和导轨的的电流决定,电枢前端中心轴线上各考察点,随着与电枢前端面距离的增大,磁通密度峰值呈衰减趋势,但衰减速度逐渐变小。研究结果有助于轨道炮膛内强磁场屏蔽与智能弹药设计。%In order to analysis the electromagnetic railgun in-bore magnetic field distribution characteristic at zero speed,a two-dimensional railgun computational model is built.Based on the magnetic diffusion equation and Ampere’s law,the current density in each part of the rail and armature is obtained.Through the Biot and Savart’s law,the magnetic flux density of the in-vestigated point which locates in front of the armature is calculated,Based on the electromagnetic induction method,the magnetic field measurement experiments are carried out.The experimental values are in agreement with the calculation values.The results show that the magnitude of the magnetic field is determined by the current flowing through the armature and rails.To the investi-gated points in the central axis in front of the armature,the magnetic flux density decreases with the increase of the distance from the investigated point to armature,but the decay rate is gradually smaller.The results are helpful for the in-bore magnetic field shielding and intelligent ammunition design.

  18. Structural design for ram of CNC milling-boring machine based on finite element analysis%基于有限元的落地镗铣床滑枕结构设计

    Institute of Scientific and Technical Information of China (English)

    石前列; 吴向东; 武友德

    2012-01-01

    为完成四川省德阳市某机械制造有限公司委托开发数控落地镗铣床的项目,从根本上提高TX6916落地镗铣床的动态性能和市场竞争力.针对滑枕内部筋板结构形式,利用有限元法分析了米字型筋板、十字型筋板和X型筋板三种不同筋板结构形式下滑枕的静、动态性能.在选定筋板形式条件下根据外壁板厚度、筋板厚度和内筋板厚度对固有频率的灵敏度分析,选择优化设计变量改进滑枕结构,对改进的结构进行有限元分析并与原有结构相比较,改进结构在静、动态性能都有显著提高.%In order to complete the designing of milling -boring machine project for Deyang Sichuan JiaLong machine manufacture company and improve the dynamic characteristics and competitiveness of the TX6916 CNC milling -boring machine,analysis for static and dynamic performance of ram is made under 3 structural types ribs such as rib-segment,cross-shaped and X-type ribs aimingat ram ribs structure,by using finite element.With the structural form of ribs being chosen,the sensitivity of the natural frequency of wall thickness,rib thickness and the thickness of concealed ribs is analyzed.Then the optimal design variables are selected to improve ram structure, which will be analyzed by finite element analysis and compared with original structure.Thus the structure has been improved significantly in static and dynamic performance.

  19. Abnormal Phenomenon Analysis of Fins’Work in Bore for the Guided Proj ectile by Gun%制导炮弹尾翼膛内工作异常现象分析

    Institute of Scientific and Technical Information of China (English)

    蔡灿伟; 张玉荣; 陶辰立; 周杰; 孙也尊

    2014-01-01

    To study mechanism of abnormal opening of the guided proj ectile ’s fins,the performance process of fins in bore was analyzed with the phenomenon that the guided proj ectile's fins were attrited and the air holes were ablated during many experiments.The ablation model of cylinder air hole was estab-lished in the effect of the high temperature and high pressure gunpowder gas and the law of diameter of air hole and pressure within the piston cylinder were obtained combining the ablation model with the one-di-mensional two-phase flow model.The calculation results show that the diameter of air hole is expanded continually in the ablative effect of gunpowder gas and the pressure of the piston cylinder is enlarged obvi-ously.The fins are opened during the gun bore in the cylinder piston role and collided with artillery rifling violently so that the fins can not work properly out of the muzzle.The results provide an important refer-ence value for designing and improving the cylinder-open fin of the guided proj ectile.%在某型制导炮弹试验过程中发生了多次尾翼片磨损、气缸气孔烧蚀现象,为分析尾翼张开异常的原因,研究了气缸张开式尾翼膛内工作过程,建立了高温高压火药气体作用下的气孔烧蚀模型,并与内弹道一维两相流模型进行了联立求解,得到了气孔直径、活塞气缸内压力的变化规律。仿真计算结果表明,受火药气体烧蚀作用的影响,气孔直径不断扩大,气缸压力明显增大,尾翼受到气缸内活塞的推动在炮膛内部张开,从而使尾翼片与膛线剧烈碰撞而使尾翼损坏,出炮口后尾翼无法正常工作。研究结果对该型制导弹药气缸张开式尾翼的设计和改进有重要参考价值。

  20. Application of In-Syringe Dispersive Liquid-Liquid Microextraction and Narrow-Bore Tube Dispersive Liquid-Liquid Microextraction for the Determination of Trace Amounts of BTEX in Water Samples.

    Science.gov (United States)

    Rahmani, Mashaallah; Kaykhaii, Massoud; Ghasemi, Elham; Tahernejad, Mohadeseh

    2015-08-01

    Two new simple and effective methods based on dispersive liquid-liquid microextraction (DLLME) procedure, termed "in-syringe DLLME (IS-DLLME)" and "narrow-bore tube DLLME (NB-DLLME)", were developed and applied for rapid and simultaneous separation and preconcentration of trace amounts of benzene, toluene, ethylbenzene and xylene isomers in water samples followed by gas chromatographic analysis. Different parameters influencing the extraction efficiency of both methods such as type and volume of the extraction solvent and the disperser solvent; pH, temperature and volume of sample solution and ionic strength of samples were investigated and optimized. Under optimal condition, the limits of detection ranged from 1.7 to 2.4 µg L(-1) for IS-DLLME and 1.5 to 2.2 µg L(-1) for NB-DLLME. Precision (as relative standard deviation) of the two techniques was between 2.1 and 4.6% for IS-DLLME and between 1.5 and 4.5% for NB-DLLME. The enrichment factors found to be between 20-29 and 31-73 for IS- and NB-DLLME, respectively. The applicability of the proposed methods was investigated by analyzing real water samples.

  1. 浅议输电线路工程钻孔灌注桩基础施工与质量监控%Cast-In-Situ Bored Pile Foundation Construction and Quality Monitoring of Engineering of Power Transfer Line

    Institute of Scientific and Technical Information of China (English)

    吕欣

    2015-01-01

    This paper analyzed and discussed construction technology of slurry supporting cast-in-place pile bored pile in slurry wall of pile foundation in electric transmission line iron tower foundation engineering,proposed key points of quality monitoring on pile-forming and underwater pouring concrete of cast-in place pile,summarized means of prevention and treatment of easily occurred trouble in construction through practical experience.%对输电线路铁塔基础工程中的桩基础主要采用的泥浆护壁钻孔灌注桩施工工艺、施工过程进行了分析和探讨,并提出了在钻孔灌筑桩成桩、水下浇筑混凝土的质量监控中应注意的一些要点,通过实践经验总结了如何在施工中预防及处理一些易出现的故障和质量问题的方法。

  2. Performance Analysis for Rack of TK42300 CNC Boring-milling Machine%TK42300型数控龙门镗铣床机架性能分析

    Institute of Scientific and Technical Information of China (English)

    郝超

    2013-01-01

    机架是数控机床重要部件之一,对机床的精度有非常重要的影响.采用有限元分析和实验研究相结合的方法,对TK42300型数控龙门镗铣床的机架性能进行深入研究,分析首轮设计图样的静态、动态、热性能特征,识别机床结构设计中的薄弱环节,进行优化、改进后试制样机.实测机床性能良好,模拟设计取得了实效.%Based on finite-element method and experiment research, rack performance of TK42300 CNC boring-milling machine was researched through analyzing static, dynamic and thermal features of the first design pattern. Weak link of machine structure design was identified. After optimization, sample machine was trial-produced. The test result demonstrates the performance of the machine is good.

  3. Borehole geophysics for delineating the geological structure in the Sakonishi prospect, the Hida area, Japan; Hida chiiki Sako nishi chiku ni okeru boring ko riyo butsuri tansa ni yoru chishitsu kozo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Katayama, H.; Hishida, H.; Yoshioka, K. [Metal Mining Agency of Japan, Tokyo (Japan)

    1997-05-27

    In order to discuss effectiveness of physical exploration in the Sakonishi prospect in the Hida area, physical exploration was carried out by utilizing bored wells. This area contains the Kamioka mine, one of the major base metal mines in Japan, where electrical exploration has been attempted several times in the past. No effective results have been obtained, however, because specific resistance contrast between mine beds and base rocks is too small, and the topography is too steep making site workability inferior. As part of the investigations on geological structures over wide areas, electrical logging (specific resistance and natural potential) was performed in fiscal 1995 and 1996 by utilizing the boreholes. Induced polarization logging was also conducted on the same boreholes. A traverse line on the ground with a length of 600 m and boreholes were used to execute specific resistance tomography. Clear extraction was possible on a fault structure which is thought related with limestone distribution and mine bed creation. However, it was not possible to identify upward continuity of zinc ores expected in the exploration. Because of not large a specific resistance contrast between zinc ores and base rocks, it is difficult to find mine bed locations only from the information on the specific resistance. 5 refs., 5 figs., 1 tab.

  4. Study on anti-fouling properties of novel five-bore PVDF blend modified membranes%新型五孔PVDF共混改性膜抗污染性能研究

    Institute of Scientific and Technical Information of China (English)

    黄健平; 邵玉敏; 刘莉莉; 马春燕; 刘纳; 奚旦立; 阎克路

    2012-01-01

    观察新型五孔PVDF共混改性纤维膜SEM形貌特征,测量改性膜的接触角和临界通量,1 # (PVDF/PMMA/TPU)、2#(PVDF/PMMA/PVC)共混改性膜分别在次临界和超临界通量下进行过滤实验.结果表明:PVDF共混改性膜具有优良的微观结构,且1 #共混膜性能较好;1#共混膜的接触角比2#共混膜小;1 #、2#共混膜的临界通量分别为10和14 L/(m2·h);1#共混膜比2#共混膜抗污染性能好;次临界通量下共混膜的运行比超临界通量下的稳定.两种共混膜分别在次临界通量下采用单独超滤和混凝十超滤工艺处理某市地表水,得出混凝+超滤工艺处理效果较好,且1 #共混膜比2#共混膜处理效果好.%The morphologies for of novel five-bore PVDF blend modified membranes were observed by SEM. The water contact angle and critical fluxes of different novel five-bore PVDF hollow fiber membranes were measured. Then the filtration experiments at sub-critical flux and super-critical flux of No. KPVDF/PMMA/TPU) blend modified membrane and No. 2 (PVDF/PMMA/PVC) blend modified membrane were carried out. The results showed that the PVDF blend modified membranes possessed excellent microstructure and the microstructure of No. 1 was better. The contact angle of No. 1 blend membrane was lower than that of No. 2 blend membrane. The critical fluxes of two blend membranes were 10 L/(m2 · h) and 14 L/(m2 · h), respectively. The anti-fouling property of No. 1 blend membrane was better than that of No. 2 blend membrane. The operating characteristic under sub-critical flux was more stable than that of under super-critical flux. Two blend membranes were used to treat ground-surface water under sub-critical flux and the effects of that with coagulation as pretreatment were studied. The results showed that the wastewater treatment performance of coagulation-ultrafiltration combination process was better than that of ultrafiltration process alone, and the wastewater treatment

  5. Reliability Evaluation of Vertical Bearing Capacity of Post-grouting Bored Piles%后注浆灌注桩桩端竖向承载力可靠性分析

    Institute of Scientific and Technical Information of China (English)

    张杰; 朱晓丽

    2015-01-01

    后注浆钻孔灌注桩目前广泛应用于软土地区中,其承载力较大,沉降较小,因此对其承载力的估算一直受到重视。研究桩端位于砂土层中的桩端后注浆灌注桩竖向抗压承载力可靠度,并编写了相应Matlab程序。考虑到在实际进行可靠度计算时,极限状态方程的确立、随机变量的选择对最后得到的可靠度指标有很大影响,比较了2个随机变量、4个随机变量以及6个随机变量这样3种情况计算同一算例的可靠度指标。对于极限状态方程的确定,本文建立了3种不同的极限状态方程,研究结果发现极限状态方程的选取对可靠度指标的影响较小,可按照实际工程掌握数据选取随机变量。由于进行可靠度研究时,随机变量的均值和标准差都是基于大量数据确定的,会有误差存在,因此研究各个随机变量的敏感性能对实际工程计算可靠度指标的精度提高有所帮助。%Post-grouting bored piles are widely used in soft soil area, whose carrying capacity is large and settlement is small, so estimation of carrying capacity is much accounted of.In this paper, the study was mainly about the reliability evaluation of vertical bearing capacity of the base-grouting bored piles which is lo-cated in the sandy soil and wrote the Matlab program about it.Considering the limit state equation, the choice of the random variables has a great influence on the reliability index.Three conditions, which are of 2 random vari-ables, 4 random variables and 6 random variables, were used to calculate the reliability evaluation of the same example.About selecting limit state equation, three different limit state equations were chosen.And the limit state equation has little effect on reliability evaluation showed in the result.So random variable can be chosen ac-cording to the practical engineering.Considering the mean value and standard deviation of random variables base on mass

  6. 祁连山天然气水合物赋存区钻孔细菌多样性%Bacterial diversity in bore holes of gas hydrate-rich deposit districts in Qilian Mountains of Northwest China

    Institute of Scientific and Technical Information of China (English)

    武淑娇; 韩路; 吕杰; 董建英; 祝有海

    2012-01-01

    分析了青海省祁连山冻土区天然气水合物赋存区DK-6钻孔的4个样品,对岩心样品进行处理提取微生物总基因组,采用PCR构建了细菌16S rDNA基因文库,4个文库包括44个OTU,其中有厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、变形杆菌门(Proteobacteria)(包括α-、β-和y-变形杆菌亚群)、放线菌纲(Actinobacteria)和异常球菌-栖热菌门(Deinococcus-Thermus)5类,煤、泥岩、粉砂岩等不同岩性的微生物群落之间显示出较大的组成差异,优势菌不同.细菌菌群多样性随采集点地质环境不同而有较明显的变化,天然气水合物含量、水含量、有机质含量等环境因素对冻土区天然气水合物赋存区中细菌菌群有一定的影响.4个样品中存在的微生物大部分可以代谢有机烃类,在天然气水合物环境的特殊条件下,外界环境因素制约了微生物的种类.%In this study, four core samples were collected from the DK-6 bore holes of gas hy-drate-rich deposit districts in the permafrost zone of Qilian Mountains, Qinghai Province of North-west China, with the total bacterial genome in the samples analyzed. Four 16S rDNA gene librar-ies were created by PCR. There were 44 OTUs, including five categories, i. e. , Firmicutes, Bacteroidetes, Proteobacteria (α-, β-, and γ-Proteobacteria) , Actinobacteria, and Deinococ-cus-Thermus, in the four gene libraries. The microbial communities of different lithology showed a relatively large composition difference, and had different dominant species. Lithology played a certain decisive role to the growth of bacteria. Bore holes DK6-12 (117.5 m) and DK6-17 (161.9 m) were of mudstone, in which, Alcaligenes xylosoxidans was the dominant bacterium. K6-23 (194.6 m) was of fine sandstone, in which, a large number of Spirosoma panaciterrae was found in cloning sequences. DK6-25 (213 m) was of coal, with the highest abundance of Pantoea ananatis. Most of the microbes presented in the four

  7. Foundation Treatment Construction Technology of Landfill by Super Down Hole Dynamic Compaction Pile Combined with Bored Pile%SDDC桩结合灌注桩的垃圾填埋场地基处理施工技术∗

    Institute of Scientific and Technical Information of China (English)

    毛正君; 陶志怀; 魏荣誉; 韩小明

    2016-01-01

    由于垃圾填埋场地具有性质复杂、厚度变化大、强度较低、压缩系数大、腐蚀性和污染性强等特点,在服务期内和封顶后都会产生大幅度的沉降。结合西安某垃圾填埋场实例,探讨了孔内深层超强夯桩( SDDC桩)结合灌注桩在垃圾填埋场地基处理中的施工技术。实践证明,采用该技术在满足地基承载力的基础上,降低了工程造价、提高了工程质量,取得了良好的社会经济效益。%Due to some characteristics of the landfill such as the complex properties, big change in thickness, low strength, large compressibility, strong corrosion resistance and polluting, it will generate settlement by a large margin during the service period and after capping. This paper cites an example of a landfill site in Xi’ an, probing into the foundation treatment construction technology of landfill by super down hole dynamic compaction pile combined with bored pile. It has been proved in practice that using this technique can meet the bearing capacity of foundation soil, at the same time, it also can reduce the engineering cost, improve the engineering quality and achieve good social and economic benefits.

  8. 落地镗铣床机械大修及数控改造%The Mechanical Overhaul and Numerical Control Transformation of Floor Type Boring-milling Machine

    Institute of Scientific and Technical Information of China (English)

    张忠旭

    2015-01-01

    数控机床是现代装备制造业中的重要组成设备,随着机电一体化进程不断深入,数控机床越来越成为机械工业技术改造的首选设备。为了提高公司机床设备装备水平,适应市场需求,提高产品质量、精度,提高生产效率,降低工人劳动强度,减少工装,缩短生产周期,公司对SKODA W250HC落地镗铣床进行了机械大修及数控化改造。本文介绍了机床机械及电气方面的现状,大修及改造方案。%Numerical control machines are important component devices in modern equipment manufacturing industry , T he NC machines more and more become the preferred machinery equipment in the mechanical reconstructing industry , along with the deepening of mechanical and electrical integration process . In order to improve the level of machine equipment , to meet market demands , to improve product quality and accu‐racy , to increase productivity efficiency , to reduce labor intensity of workers and frock and shorten the production cycle , SKODA and W250HC floor type boring -milling machine are overhauled and NC trans‐formed in our company . T he machine present situation and overhaul project is introduced in this paper .

  9. Rapid Construction Technology for a Shallow-buried Bored Tunnel in Sandy Pebble Stratum%砂卵石地层浅埋暗挖法快速施工技术

    Institute of Scientific and Technical Information of China (English)

    刘魁刚; 王文正; 裴书锋

    2011-01-01

    The running tunnel of phase three of the Beijing Subway Line 4 passes through a sandy pebble stratum, which creates construction risks of surrounding rock collapse, tunnel bottom swell, sand outflow and soil settlement above the roof. It also affects the road and bridge safety and results in difficult drilling and grouting. This paper addresses the optimization of the design and grouting parameters of small conduits and discusses the construction principles of "early covering, fine short tube, less disturbance, quick setting, abutment reinforcing and middle slotting" regarding the bored tunnel with a shallow overburden at the sandy pebble stratum. The construction technology of the bench method is introduced, which includes the key points of counter core soil excavation, small conduit grouting and locking anchor pipe, with a monthly advance rate of 60~70 m.%北京地铁四号线三期区间隧道穿越砂卵石地层,存在围岩易塌落、隧道底部起鼓和涌砂、顶板上方土体沉降,影响道路和桥梁安全等施工风险,并且不易钻孔注浆,工效较低.针对以上问题,改进了小导管设计参数和注浆参数,提出了砂卵石地层浅埋暗挖法“早封面、管细短、少扰动、快凝固、固拱脚、中拉槽”施工原则,施工效果较好,月进度达60~70 m.文章介绍了砂卵石地层台阶法施工工艺,提出了下台阶反核心土开挖,以及小导管注浆和锁脚锚管施工要点.

  10. Adaptronic tools for superfinishing of cylinder bores

    Science.gov (United States)

    Roscher, Hans-Jürgen; Hochmuth, Carsten; Hoffmann, Michael; Praedicow, Michael

    2012-04-01

    Today in the production of internal combustion engines it is possible to make pistons as well as cylinders, for all practical purposes, perfectly round. The negative consequences of the subsequent assembly processes and operation of the engine is that the cylinders and pistons are deformed, resulting in a loss of power and an increase in fuel consumption. This problem can be solved by using an adaptronic tool, which can machine the cylinder to a predetermined nonround geometry, which will deform to the required geometry during assembly and operation of the engine. The article describes the actuatory effect of the tool in conjunction with its measuring and controlling algorithms. The adaptronic tool consists out the basic tool body and three axially-staggered floating cutter groups, these cutter groups consist out of guides, actuators and honing stones. The selective expansion of the tool is realised by 3 piezoelectric multilayer-actuators deployed in a series - parallel arrangement. It is also possible to superimpose actuator expansion on the conventional expansion. A process matrix is created during the processing of the required and actual contour data in a technology module. This is then transferred over an interface to the machine controller where it is finally processed and the setting values for the piezoelectric actuators are derived, after which an amplifier generates the appropriate actuator voltages. A slip ring system on the driveshaft is used to transfer the electricity to the actuators in the machining head. The functioning of the adaptronic form-honing tool and process were demonstrated with numerous experiments. The tool provides the required degrees of freedom to generate a contour that correspond to the inverse compound contour of assembled and operational engines.

  11. Bore hole image well logging technique

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Young Kwon; Kim, Geon Young; Bae, Dae Seok; Kim, Kyung Su; Ryu, Ji Hoon; Park, Kyung Woo; Ji, Sung Hoon

    2009-08-15

    As one of the investigation method which the underground geological features is direct drill investigation geological features condition of underground directness it will can confirm visually there is a strong point but the drill nose in compliance with war potential or a shock from the digging through process which it knows the orientation scattering, or, the capital where the destruction action which is mechanical will accompany it will be, also to the case where the ground condition is defective the nose Oh there is a possibility of being difficult also oneself getting to the evaluation which ground is accurate with being difficult, it operated and it was come. As the method which solves like this problem drill worker image photographing which is the possibility of getting the burn was introduced in about the drill worker wall. Drill worker image photographing it will be able to classify with 3 kind of electricity, the sound wave and optical science etc. on a large scale and these people are controlled and respectively amplitude and staring reaction of electric resistivity reaction and the sound wave, in order for the pixel price which digitizes optical science photograph etc. to confront clearly in spatial location it will be able to provide information concretely about rock floor etc., discontinuity surface situation and of the public wall travelling and inclination and the clearance

  12. 基于互联网的隧道掘进机故障筛选及预警系统开发%The Development of Tunnel Boring Machine Malfunction Screening and Early Warning System Based on Internet

    Institute of Scientific and Technical Information of China (English)

    张迅博

    2015-01-01

    国内盾构机在施工时,在盾构机掘进过程中时常会遇到各种突发情况,然而报警信息无法及时传递到技术专家手中,这为盾构施工埋下了安全隐患。为解决这一困难,文章设计了一套基于互联网的隧道掘进机故障筛选及预警系统,能实现实时搜集多台盾构机施工中的报警信息,通过因特网汇集到远端服务器,利用故障筛选及预警系统,实时向技术专家,业主,监理发出预警短信。系统保障了施工人员及机械的安全,提高了管理效率节约了项目成本。%Domestic Shield in the construction,in the course of the shield tunneling machine often encounter a variety of emergency situations,but the alarms information can not be delivered in time to the hands of technical experts,which buried a security risk for the shield construction.To address this problem,design a tunnel boring machine malfunction screening and early warning system based on the Internet,can achieve real-time collection of multiple shield machine construction alarm information collection to the remote server through the Internet, the use of screening and early warning failure system, real-time early warning messages to technical experts,owners, supervision.The system protects the safety of construction workers and machinery,and the same time the system improves the management efifciency savings in project costs.

  13. Based on B/S structure of the tunnel boring machine operation simulation and fault diagnosis system%基于B/S架构的掘进机运行仿真与故障诊断系统研究

    Institute of Scientific and Technical Information of China (English)

    汤其建

    2015-01-01

    Yongcheng Vocational College developed to run the simulation and fault diagnosis system based on In‐ternet technology roadheader .The system uses advanced computer simulation technology virtual Tunneling sud‐den disposal and roadheader typical faults to troubleshoot .Teachers can set a variety of unexpected situations and failures on a server or superuser machine;Students can be performed on the brow ser side virtual training to deal with unexpected situations , troubleshooting , the status process and troubleshooting process , you can choose a variety of simulation tools and test equipment ,process automatic record .The system was applied to the teaching and training ,so that students can not only deepen the Tunneling relevant expertise to understand ,and can exercise their ability to handle emergencies and Diagnostics boring machine failure .The system is to improve student interest in learning and learning efficiency w hile reducing costs and time costs of teaching in schools and training institutions .%永城职业学院开发了基于网络技术的掘进机运行仿真与故障诊断系统。该系统利用先进的计算机虚拟仿真技术实现巷道掘进突发状况处置和掘进机典型故障诊断排除。教师可以在服务器或超级用户机上设置各种突发状况和故障;学生可以在浏览器端上进行虚拟实训,应对突发状况、排除故障,在状况处理和排除故障过程中,可选用各种仿真工具和检测仪器,过程自动记录。将该系统运用到教学和培训中,不但可以使学员加深对巷道掘进相关专业知识的理解,而且可以锻炼其处置突发状况和诊断掘进机故障的能力。该系统在提高学员学习兴趣和学习效率的同时,还能降低学校和培训机构的教学成本和时间成本。

  14. 氯化物环境暗挖海底隧道支护结构的耐久性设计%The Durability Design of Subsea Bored Tunnel Support Structures under Chloride Corrosion

    Institute of Scientific and Technical Information of China (English)

    宋超业; 贺维国

    2016-01-01

    A subsea tunnel suffers the long-term impact of chloride corrosion, and with a required design service life of 100 years or more, many more studies of durability design are needed than for normal tunnels. Current study of subsea tunnel durability focuses on material selection and the mix proportion of reinforced concrete structures. This paper gives a detailed analysis of environmental conditions, relevant code specifications and durability design principles for subsea bored tunnels in chloride environments and proposes the concept of paying equal attention to the durability design and bearing capacity design as well as reserving enough space for later restoration. The analy-sis shows that high-strength high-performance concrete should be adopted for subsea tunnel linings in order to im-prove concrete density and to resist seawater corrosion, and the limited groundwater drainage principle should be ad-opted for mined subsea tunnels to ensure effectiveness of their drainage systems.%海底隧道长期受海水氯化物环境的影响,而隧道的设计使用年限为100年甚至更长,这就要求设计中对于其耐久性要比常规隧道做出更多的研究.目前海底隧道耐久性研究主要集中在钢筋混凝土结构的材料选择和配合比设计.文章针对氯化物环境下的矿山法海底隧道,对其环境条件、规范要求和耐久性设计原则等进行了详细分析,提出了耐久性设计应与结构承载力设计并重、预留空间满足后期可修复要求的理念.隧道衬砌结构应采用高强高性能混凝土,提高其密实性抵抗海水侵蚀;矿山法隧道采用限量排放地下水处理,保证排水系统通畅可靠.

  15. 量度及預測隧道鑽機的土傳噪音及震動%Measurement and prediction of groundborne noise and vibration from a tunnel boring machine

    Institute of Scientific and Technical Information of China (English)

    何偉麟

    2006-01-01

    在市區進行夜間隧道鑽挖工程所産生的土傳噪音及震動,容易引起投訴.現時的技術難以準確預測噪音及震動的級數,而隧道工程的進度也常因進行隧道鑽挖工程時產生過大的土傳噪音及震動而延誤.本文所提述的新技術,可以更準確地量度及預測鑽機震動强度及土壤傳震的特性.這個技術包括測量單位衝擊力及隧道鑽機摩擦力所産生的震動級數.其實早於80於代,美國政府運輸部門(U.S.Dept of Transportation Federal Transit Administrative)已研發相關的技術,並將該技術應用於鐵路土傳噪音量度及預測上.本文報告隧道鑽機所產生的土傳噪音及震動級數1/3倍频帶數值的量度及預測.比較地面震動峰值速度(PPV)、最高(Lmax)噪聲和振動級數按快速和緩慢的時間常數和整體百分比(Percentile)數值列出.%A new empirical method for prediction of groundborne noise and vibration (GBN&V) induced by tunnel boring machine (TBM) has been developed. The method is based on empirical determination of ground vibration transmissibility and TBM vibration source strength. The method includes measurements of ground vibration levels caused by unit force impacts and TBM operation at various setbacks. With these measured data, the ground vibration transfer mobility and TBM vibration source strength are determined separately. Prediction of TBM-induced GBN&V is performed by combining the determined TBM vibration source strength and the further measurement data of ground vibration transfer mobility by impacting in boreholes along the proposed tunnel alignment. Predicted GBN&V levels are presented in 1/3 octave spectrum at various setbacks from the tunnel alignment.Comparisons are given in predicted peak particle velocity (PPV), maximum noise and vibration levels in fast and slow time constant and overall percentile values (cumulative probability distributions).

  16. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  17. TX1600G 数控镗铣加工中心滚珠丝杠热特性分析%Thermal Characteristics Analysis of Ball Screw of TX1600G CNC Boring and Milling Machining Center

    Institute of Scientific and Technical Information of China (English)

    孙军; 秦显军; 钱彬彬; 黄圆

    2015-01-01

    This paper takes TX1600G CNC bor-ing and milling machining center as example and mainly studies the impact of different feed speed and coolant flow on the system heat balance,under the conditions of the moving heat source.To un-derstand the ball screw in actual working condi-tions,ANSYS was first used to establish a simpli-fied three dimensional model of the ball screw, and then the heat source was moved to simulate heat transmission on nut and bearing,so the tem-perature model and thermal error compensation model of lead screw are established.Results show that the increase of feed speed can shorten the time for heat balance of the system,but the thermal e-quilibrium temperature was increased;coolant flu-id can effectively reduce the thermal equilibrium temperature and the thermal equilibrium time. Thermal error modeling and the analysis of tem-perature field also provide necessary theoretical ba-sis to the thermal compensation of the system.%以 TX1600G 数控镗铣加工中心为例,主要研究在移动热源施加条件下,不同的进给速度以及冷却液流量对系统热平衡的影响。为得到滚珠丝杠在实际工作中的状态,利用 ANSYS 建立丝杠的简化三维模型,施加移动热源来模拟螺母和轴承的传动热量,从而得到丝杠的温度模型,建立热误差补偿模型。结果表明,进给速度的增加可以缩短系统的热平衡时间,但热平衡温度有所升高;冷却液可以有效地降低热平衡温度和缩短热平衡时间。热误差模型建立和温度场分析,为系统的热补偿提供必要的理论依据。

  18. A Comparison of Cast-in-situ Bored Pile Construction Process in Pebble Bed%卵石层中钻孔灌注桩施工工艺比较

    Institute of Scientific and Technical Information of China (English)

    张波; 温玉启

    2013-01-01

      兰州市深安黄河大桥基础为钻孔灌注桩,地质条件以卵石层为主,桩端不入岩层。采用传统的冲击钻机成孔,施工效率低下,故较小桩径的钻孔桩采用旋挖钻机成孔,施工效率高,且无大功率用电需求。但旋挖钻机成孔后的孔壁相对不够稳定,施工阶段应遵循“三快”原则,即“快成孔、快下笼、快灌桩”,从而有效地控制成桩质量,尤其是沉渣厚度。通过2种钻机成桩后的检测及试验报告,以实际数值为依据,阐述了2种钻机在卵石层地质条件成孔的优缺点。%  The pile foundation of Lanzhou Shen’an Yellow River Bridge engineering is cast-in-situ bored pile with the engineering geological conditions of pebble layer in the main and the pile tip no entering the rock stratum. The work efficiency of drilling by the traditional percussive drilling machine will be low, while the work efficiency of rotary drilling machine will be higher when drilling the smaller diameter pile hole, and without large power electric. But the pile hole drilled by rotary drilling machine is instable. To control the construction quality, especially, the thickness of sediment, the principle of the Three Fast must be obeyed during the operation, that is, drilling the pile hole must be fast; placing the steel cage must be fast; pouring pile must be fast. According to the detection & test reports on the two drilling machines and the actual data, the advantages & disadvantages of the two drilling machines working in the pebble bed are discussed in detail.

  19. 12V柴油机机体精铣缸面、精镗气缸孔数控专机的结构设计与分析%Structural Design and Analysis for a Special CNC Machine for Precise Milling Head Face and Precise Boring Cylinder Hole of a V12 Diesel Engine Block

    Institute of Scientific and Technical Information of China (English)

    马敏莉; 王建章

    2013-01-01

    介绍了12V柴油机机体精铣缸面、精镗气缸孔数控专机设计的关键技术及设计要点.设计中根据12V机体零件精铣缸面、精镗气缸孔的工序要求,有针对性地设计了机床的各个主要部件,解决了缸面平面度、缸套孔止口深度1100.05mm、底面0.3.~0.5.mm斜面、ф16300.25孔与止口的过渡圆角R0.50-0.2 mm、各缸止口与缸面的平行度、各缸孔与缸面的垂直度等加工中的瓶颈问题,确保零件工序精度及加工效率.%Key technologies and aspects involving in the design of a special CNC machine for precise milling head face and precise boring cylinder hole of a V12 diesel engine were explained.Based on the sequential requirements of the process for precision machining head face and bore,major components of a special CNC machine were designed,solving critical machining challenges such as engine blockhead flatness,parallelism between the blockhead and the flange of all cylinders,perpendicularity between cylinder bores and the blockhead,and at the same time providing an engine liner depth of 110+0.05 mm,an inclined bottom of 0.3 ° ~ 0.5 ° mm,and the transitional round of R0.50-0.2mm between the ф1630+0.25 hole and the flange.So required machining precisions and productivity are ensured.

  20. Trimerization process of vegetables oils and fats and its application in additives for synthetic fluids used in the perforation of petroleum well bore; Processo de trimerizacao de oleos vegetais e acidos graxos e sua aplicacao em aditivos para fluidos sinteticos utilizados na perfuracao de pocos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Viviane X.; Souza, Roberta C.R.; Coelho, Anderson S.; Lopes, Grazielle; Yoshida, Renan O.; Goncalves, Gizelle de Fatima G.D.V.; Silva, Sandra Regina da [Centro Tecnico Aeroespacial (CTA), Sao Jose dos Campos, SP (Brazil). Centro de Tecnologia; Poland Quimica Ltda., Macae, RJ (Brazil)

    2007-07-01

    Derivatives of vegetable oils and fatty acids such epoxides, polyols and fatty acid dimmers are industrially used for a variety of polymer applications, such as additives for plastics and composites and in filtration control aid in in perforation fluids as well as in the synthesis of polyamides and polyurethanes. In this article a vegetable oil was chemically modified by trimerization and used as filtration control and in a paraffin based perforation fluid. The rheology and filtration parameters were studied and the results were compared to desired specifications to maintenance of stability of well bore. (author)

  1. 港珠澳大桥非通航孔桥钻孔平台施工方案比选%Comparison and Selection of Construction Schemes for Boring Platform of Non-Navigable Span Bridge of Hong Kong-Zhuhai-Macau Bridge

    Institute of Scientific and Technical Information of China (English)

    刘运洪

    2015-01-01

    The non‐navigable span bridge of Contract CB05 of the Hong Kong‐Zhuhai‐Macao Bridge is a 85‐m span steel and concrete continuous composite girder bridge .The foundations for the piers of the bridge are the ones of steel pipe composite piles .At each pier ,6 composite piles are provided and there are totally 372 piles for the whole bridge .In the light of the structural fea‐tures and construction difficulties of the bridge ,the construction schemes of a common boring plat‐form of the"steel pipe piles+ sectional steels" structure (Scheme 1) and an integral boring plat‐form of the"integral steel truss type"structure (Scheme 2) were proposed for construction of the foundations .T hrough comparison of those aspects of the civilization construction ,safety ,environ‐ment protection ,construction efficiency and construction cost ,it was determined that the Scheme 2 should be selected .For the Scheme 2 ,the components of the boring platform were all fabricated in workshop following the standardization requirements and were welded into the integral steel truss structure .The steel truss structure was then transported by ship to the pier site where the structure would be installed or integrally removed for repeated usage at other pier sites by floating crane and at this stage , the construction of the boring platform was completed . The selected Scheme 2 can effectively shorten the time interval of shifting the platform from pier site to pier site and has advantages of high efficiency , safety , environment protection , energy saving and fast speed .%港珠澳大桥CB05标非通航孔桥为跨径85 m的钢-混组合连续梁桥,采用钢管复合桩基础,每墩均由6根钢管复合桩组成,全桥共372根。针对该桥结构特点和施工难点,桩基础施工提出了“钢管桩+型钢”结构的普通钻孔平台(方案1)和“整体桁架式”结构的整体钻孔平台(方案2)施工方案,通过文明施工、安全环保、

  2. 沿海城市防洪工程水下钻孔灌注桩的质量控制要点浅析%Brief Analysis on Flood Control Project of Quality Control of Underwater Piles Bored Piles in Coastal City

    Institute of Scientific and Technical Information of China (English)

    牛秀博; 谢利云

    2014-01-01

    近年来,我国沿海地区防洪能力逐渐得到加强,而防洪工程所处场地基础较差,根本无法满足防洪工程的要求,在这种天然地基上建造防洪堤,若处理不好,就可能发生局部破坏甚至整体滑动等失稳现象。结合浙江瑞安城市防洪堤三期工程,浅析在沿海地区复杂地质环境中进行水下钻孔灌注桩作业的施工要点及加强施工中质量控制的有效手段,提出保证成桩质量的措施,为类似工程地质条件钻孔灌注桩水下施工提供参考。%In recent years , flood control capacity has been strengthened gradually in coastal areas , ground basis on the flood control engineering is poor , which could not meet the requirements of flood control engineering.If the processes are not good to build a levee on the natural foundation , local damage and even whole sliding instability phenomenon may occur.Combined with the levee in phaseⅢproject in zhejiang ruian city , the key points of construction of underwater piles bored piles and ef-fective methods for quality control during construction are analyzed in complex geological environment of coastal city , and measures to ensure the piles quality are put forward , which can provide the refer-ence for the similar engineering geological conditions of underwater piles bored piles construction.

  3. 反井钻机联合钻爆法在大断面煤仓施工中的研究与应用%Study and Application of Raise Boring Machine with Drilling and Blasting Method to Construction of Mine Large Cross Section Coal Bunker

    Institute of Scientific and Technical Information of China (English)

    许传峰

    2013-01-01

    According to the large cross section,high difficult construction,low safety coefficient and other features of the coal bunker at the-318m level mine shaft bottom,with the comparison analysis,a raise boring machine combined with the drilling and blasting construction was determined and applied.From the blind shaft construction,reaming of the coal bunker,concrete lining support and others,the paper introduced the rapid construction technology.The results showed that the application of the raise boring machine combined with the drilling and blasting method to the construction of the coal bunker at the mine shaft bottom would have high mechanized degree,low labor intensity,safety,rapid construction speed,high efficiency and series advantages and would be a value to be promoted.%针对-318m水平井底煤仓断面大、施工难度大,安全系数低等特点,通过对比分析,决定采用反井钻机联合钻爆法施工,并从溜矸井施工、煤仓刷大、混凝土砌碹支护等方面介绍了快速施工技术,结果表明,采用反井钻机联合钻爆法施工井底煤仓,具有机械化程度高、劳动强度低、安全、施工速度快、效率高等一系列优点,值得推广应用.

  4. Fiscal 2000 project of inviting proposals for international joint research - invitation for international proposal (power generation No.15). Achievement report on development of guided boring system for buried power network; 2000 nendo kokusai kyodo kenkyu teian kobo jigyo - kokusai teian kobo (hatsuden No.15). Denryokumo chichuka hikaisaku kanro kensetsu koho no kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    What impedes the popularization of the guided boring system is the functional insufficiency of the drilling position measuring method. For the purpose of properly dealing with the situation, efforts are made to develop a new drilling position measuring method which is highly reliable even when there exist previously buried pipes or electromagnetic noise. Activities are conducted in the two sections of (1) the study of an drilling position measuring method not to be easily affected by magnetic noise and (2) the study of a method for detecting previously buried objects. In section (1), based on the technology of a drilling position measuring system (locator) which is currently the most popular among horizontal drilling systems, a signal processing technology capable of reducing the effect of noise and a new position measuring method are contrived, and it is proved by the use of an experimenting system that they work effectively. In section (2), with attention paid to the small horizontal drilling device, an underground radar technology with the radar probing into the ground from the ground surface or from a drilling head is studied as an effective and easy-to-use method for detecting previously buried steel pipes. (NEDO)

  5. Thermal Characteristics Analysis of the Ram System of TK6920 Heavy-duty CNC Floor-type Boring and Milling Machine Tool Based on ANSYS%基于ANSYS的TK6920数控铣镗床滑枕系统热特性分析

    Institute of Scientific and Technical Information of China (English)

    韩江; 昂金凤; 夏链; 丰云

    2012-01-01

    以TK6920数控铣镗床滑枕系统为研究对象,研究了其热态特性及其对机床性能的影响.首先运用三维软件对其进行三维实体建模,计算系统的热源以及相应的边界条件;其次运用有限元软件仿真计算滑枕系统的稳态温度场分布以及热平衡时间;最后根据分析结果提出改善滑枕系统热态特性的措施.%The effect of thermal properties on performance was determined for the ram system of a TK6920 heavy-duty CNC floor-type boring and milling machine tool. First, the three-dimensional model of the ram system was established with 3Dsoftware. And calculated the thermal source, confirmed the boundary conditions. After that, the constant temperature field distribution and thermal equilibrium time of the ram system was simulated and calculated with the finite element analysis software. At last, according to the result, some measures to optimize the thermal characters of the ram system were put forward.

  6. 钻孔挤密桩处理强湿陷性黄土地基试验研究%Field tests on pre-bored compaction lime-soil pile (down-hole dynamic compaction method) to improve serious collapsible loess

    Institute of Scientific and Technical Information of China (English)

    刘志伟; 申汝涛

    2009-01-01

    挤密桩法用于处理湿陷性黄土地基,可有效地消除土的湿陷性和提高地基承载力.某拟建电厂工程针对强湿陷性黄土地基,采用钻孔挤密桩(DDC工法)复合地基的处理方法开展现场试验研究.通过采用载荷试验、标准贯入试验等原位测试方法,对桩间土、桩体及复合地基的承载性能、变形参数进行了评价和分析,重点进行了自然工况和浸水工况下的对比研究,对地基处理效果进行了综合评价.%The compaction method used to control the subsoil of collapsible loess can eliminate collapsibility and improve bearing capacity of loess effectively. For serious collapsible loess in a power plant to be constructed, pre-bored compaction lime-soil piles (down-hole dynamic compaction method) field test studies were carried out. After the construction of the test piles were finished, a lot of in-situ tests including plate loading test, standard penetration test, etc., were used to evaluate the bearing capacity of the soil between piles, the piles and the composite foundation, and to test the deformation parameters. Especially, comparative research between natural status and soaked status of composite foundation as well as comprehensive evaluation of effects of ground treatment were carried out.

  7. Average is Boring: How Similarity Kills a Meme's Success

    Science.gov (United States)

    Coscia, Michele

    2014-09-01

    Every day we are exposed to different ideas, or memes, competing with each other for our attention. Previous research explained popularity and persistence heterogeneity of memes by assuming them in competition for limited attention resources, distributed in a heterogeneous social network. Little has been said about what characteristics make a specific meme more likely to be successful. We propose a similarity-based explanation: memes with higher similarity to other memes have a significant disadvantage in their potential popularity. We employ a meme similarity measure based on semantic text analysis and computer vision to prove that a meme is more likely to be successful and to thrive if its characteristics make it unique. Our results show that indeed successful memes are located in the periphery of the meme similarity space and that our similarity measure is a promising predictor of a meme success.

  8. Helical Feed Milling with MQL for Boring of Aluminum Alloy

    Science.gov (United States)

    Sasahara, Hiroyuki; Kawasaki, Makoto; Tsutsumi, Masaomi

    MQL is applied to the helical feed milling hole-making process of aluminum alloy. It is difficult to drill on aluminum alloy without cutting fluid because the adhesion to the tool leads to a chip jam, the tool breakage or low accuracy. By employing the helical feed milling, cutting temperature will decrease, each chip length will become short and a chip jam in a hole will be avoided, because the intermittent cutting is realized. As a result of employing the helical feed milling with MQL, it was shown that the shape error is decreased, a burr formation is decreased, machining temperature becomes low and the cutting force becomes small comparing with drilling process. Shape error by helical feed milling with MQL is comparable with that with flood coolant. In this case, small mist particle counts under 5μm, which affects working environment, are almost constant if the spindle speed varies. Scattered mist particle counts are less when MQL is employed over 20000 min-1 spindle speed comparing with the flood coolant.

  9. "It's Boring": Female Students' Experience of Studying ICT and Computing

    Science.gov (United States)

    Pau, Reena; Hall, Wendy; Grace, Marcus

    2011-01-01

    The declining number of women in computing is a cause for concern for those in education and the IT industry. A diverse workforce is necessary for there to be a creative balance in the IT industry. The reasons for this decline are varied and can be attributed to factors such as schooling, parental influences and the media. This article focuses on…

  10. Research on Bored Bearing Characteristics in Xi’an

    Directory of Open Access Journals (Sweden)

    Zhang Lipeng

    2015-01-01

    Full Text Available To analyze the influence of different soil properties on pile foundation load-bearing characteristics, taking a section of railway in Xi’an and a bridge of Xi’an as test area, and by field static load test to study load transfer characteristics after the test piles under axial pressure, including the distribution of axial force, pile lateral friction, tip resistance traits, ultimate bearing capacity determine, and compare with the theory bearing capacity. Experimental results show that, adjacent soil properties change large, axial force and lateral friction mutation at the junction of corresponding soil layer. Silty clay in different parts is below ground, and its lateral friction plays much difference. Pile lateral friction plays an important role in bearing capacity, but the role of round gravel soil end bearing capacity to pile bearing capacity can’t be ignored. Tests calculate pile bearing capacity significantly larger than standardized formula calculation bearing capacity, which are respectively 55.35% and 119.1%. And give the similar project condition the suggested values of pile bearing capacity and soil friction, to provide reference for similar pile foundation design.

  11. Development of small bore, high speed tapered roller bearing

    Science.gov (United States)

    Morrison, F. R.; Gassel, S. S.; Bovenkerk, R. L.

    1981-01-01

    The performance of four rolling bearing configurations for use on the input pinion shaft of a proposed commercial helicopter transmission was evaluated. The performance characteristics of a high speed tapered roller bearing operating under conditions comparable to those existing at this input pinion shaft were defined. The tapered roller bearing shaft support configuration was developed for the gearbox using commercially available bearing designings. The configuration was optimized and interactive thermomechanically system analyzed. Automotive pinion quality tapered roller bearings were found to be reliable under load and speed conditions in excess of those anticipated in the helicopter transmission. However, it is indicated that the elastohydrodynamic lubricant films are inadequate.

  12. Microcomputer Boring and Subsurface Data Package: User’s Guide.

    Science.gov (United States)

    1985-09-01

    find &bornum STORE SID TO BORSIDM STORE STR(BORSIDN,5,0) TO BORSIDC j STORE TOPiHOLE TO TOPELN store proj:name to projm store site:name to sitem STORE...LASTEL2 .AND. LINEL BOTEL2 * 0O WHILE INDX2 = 1 * @ LINE, COL2+3 SAY ’EL=’ @ LTNE, COL2+7 SAY BOTEL2 USING �.99’ j STORE INDX2+1 TO INDX2 END DO * ENDIF

  13. A METHOD OF PROVIDING BURR-FREE BORES

    DEFF Research Database (Denmark)

    2004-01-01

    By thermal-based removal of material, for instance by way of laser drilling or laser ablation, the material is removed from the article (2) in form of steam or drops. The material is removed by being subjected to a short-term intense laser pulse (4) causing a generation of considerable pressure...... from vaporised and/or ionised material. As a result, vaporised melt material is sprayed to the sides or upwards along the sides of a drilled hole. These squirts can either damage the surface around the processed area or result in an upward burr. The method according to the invention provides...... an additional local steam/plasma pressure causing the ejected material to change direction in such a manner that the surface of the material is not damaged or a stricking burr is not formed. The local steam/plasma pressure can, for instance, be provided by an intense secondary laser beam being emitted downwards...

  14. Average is Boring: How Similarity Kills a Meme's Success

    OpenAIRE

    Coscia, Michele

    2014-01-01

    Every day we are exposed to different ideas, or memes, competing with each other for our attention. Previous research explained popularity and persistence heterogeneity of memes by assuming them in competition for limited attention resources, distributed in a heterogeneous social network. Little has been said about what characteristics make a specific meme more likely to be successful. We propose a similarity-based explanation: memes with higher similarity to other memes have a significant di...

  15. Green girls and bored boys? Adolescents' environmental consumer learning

    DEFF Research Database (Denmark)

    Grønhøj, Alice

    2006-01-01

    that adolescents conceptualize environmental issues in quite traditional, individualistic, "non-radical" terms. A substantial amount of parental influence appears to be exerted on adolescents' learning within this field. However, some differences in the roles of fathers and mothers in this process could...

  16. Review on advanced composite materials boring mechanism and tools

    Science.gov (United States)

    Shi, Runping; Wang, Chengyong

    2011-05-01

    With the rapid development of aviation and aerospace manufacturing technology, advanced composite materials represented by carbon fibre reinforced plastics (CFRP) and super hybrid composites (fibre/metal plates) are more and more widely applied. The fibres are mainly carbon fibre, boron fibre, Aramid fiber and Sic fibre. The matrixes are resin matrix, metal matrix and ceramic matrix. Advanced composite materials have higher specific strength and higher specific modulus than glass fibre reinforced resin composites of the 1st generation. They are widely used in aviation and aerospace industry due to their high specific strength, high specific modulus, excellent ductility, anticorrosion, heat-insulation, sound-insulation, shock absorption and high&low temperature resistance. They are used for radomes, inlets, airfoils(fuel tank included), flap, aileron, vertical tail, horizontal tail, air brake, skin, baseboards and tails, etc. Its hardness is up to 62~65HRC. The holes are greatly affected by the fibre laminates direction of carbon fibre reinforced composite material due to its anisotropy when drilling in unidirectional laminates. There are burrs, splits at the exit because of stress concentration. Besides there is delamination and the hole is prone to be smaller. Burrs are caused by poor sharpness of cutting edge, delamination, tearing, splitting are caused by the great stress caused by high thrust force. Poorer sharpness of cutting edge leads to lower cutting performance and higher drilling force at the same time. The present research focuses on the interrelation between rotation speed, feed, drill's geometry, drill life, cutting mode, tools material etc. and thrust force. At the same time, holes quantity and holes making difficulty of composites have also increased. It requires high performance drills which won't bring out defects and have long tool life. It has become a trend to develop super hard material tools and tools with special geometry for drilling composite materials.

  17. Boring and Sealing Rock with Directed Energy Millimeter-Waves

    Science.gov (United States)

    Woskov, P.; Einstein, H. H.; Oglesby, K.

    2015-12-01

    Millimeter-wave directed energy is being investigated to penetrate into deep crystalline basement rock formations to lower well costs and to melt rocks, metals, and other additives to seal wells for applications that include nuclear waste storage and geothermal energy. Laboratory tests have established that intense millimeter-wave (MMW) beams > 1 kW/cm2 can melt and/ or vaporize hard crystalline rocks. In principle this will make it possible to create open boreholes and a method to seal them with a glass/ceramic liner and plug formed from the original rock or with other materials. A 10 kW, 28 GHz commercial (CPI) gyrotron system with a launched beam diameter of about 32 mm was used to heat basalt, granite, limestone, and sandstone specimens to temperatures over 2500 °C to create melts and holes. A calibrated 137 GHz radiometer view, collinear with the heating beam, monitored real time peak rock temperature. A water load surrounding the rock test specimen primarily monitored unabsorbed power at 28 GHz. Power balance analysis of the laboratory observations shows that the temperature rise is limited by radiative heat loss, which would be expected to be trapped in a borehole. The analysis also indicates that the emissivity (absorption efficiency) in the radiated infrared range is lower than the emissivity at 28 GHz, giving the MMW frequency range an important advantage for rock melting. Strength tests on one granite type indicated that heating the rock initially weakens it, but with exposure to higher temperatures the resolidified black glassy product regains strength. Basalt was the easiest to melt and penetrate, if a melt leak path was provided, because of its low viscosity. Full beam holes up to about 50 mm diameter (diffraction increased beam size) were achieved through 30 mm thick basalt and granite specimens. Laboratory experiments to form a seal in an existing hole have also been carried out by melting rock and a simulated steel casing.

  18. The Deceptively Boring PSR J1738+0333

    CERN Document Server

    Freire, Paulo

    2010-01-01

    We present preliminary results of 7 years of Arecibo timing of the pulsar-white dwarf binary PSR J1738+0333. We can measure the proper motion, parallax with excellent precision and have detected the orbital decay. Furthermore, the companion has been detected at optical wavelengths and a mass ratio of 8.1 +/- 0.3 has been measured from the orbital variation of its Doppler shift. Once the companion mass is determined from the optical measurements, this system will provide strong limits for the radiation of dipolar gravitational waves. Assuming that general relativity holds, the fast-improving measurement of the orbital decay, combined with the measurement of the mass ratio, will provide an independent and precise measurement of the component masses.

  19. Self-Boring Pressuremeter in Pluvially Deposited Sands.

    Science.gov (United States)

    1987-06-01

    The corresponding values of GURo and GRUo are given in Tables 6 through 10. The same tables also show the values of maximum dynamic shear modulus...the GURO and GO values it is necessary to consider other factors influencing the deformation characteristics of sand. Among them, the most relevant

  20. Comparing dynamic and static test results of bored piles

    OpenAIRE

    Long, Michael

    2007-01-01

    Due to increasing time, cost and transportation difficulties, Irish contractors are seeking an alternative to conventional static pile load tests. As a result several firms have adopted dynamic testing techniques to supplement and in some cases to replace conventional static tests. In order to assess the reliability of the systems and to address the concerns of owners and consulting engineers, a database comprising 43 pairs of static and dynamic tests on piles from 24 sites aro...

  1. The Tensile Capacity Of Bored Piles In Frictional Soils

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Andersen, Allan; Damkilde, Lars

    2008-01-01

    Three series of 10 piles each were installed in two different locations. The length of the piles varied from 2 to 6 m and the diameters were 14 and 25 cm. The piles were constructed above the groundwater table using continuous flight augers and the concrete was placed by gravity free fall....... The piles were tested to failure in axial uplift and the load-displacement relations were recorded....

  2. Emphasis: Five Ways to Cure Boring Student Writing.

    Science.gov (United States)

    Foster, Mary Ellen

    A careful use of emphasis by students in their writing can be promoted by some exercises assigned by composition teachers. A drawing exercise can help students learn that changing the length of sentences makes paragraphs more interesting. Using Elizabeth Kubler-Ross's five categories of grief to consider times of depression in students' lives…

  3. Bewitched, Bothered, and Bored: Harry Potter, The Movie.

    Science.gov (United States)

    Nel, Philip

    2002-01-01

    Explores the Harry Potter phenomenon with college students in a university course. Compares the first book with the first movie. Presents an in-depth discussion of the movie and how it relates to the book. (SG)

  4. Grammar Teaching and Learning in L2: Necessary, but Boring?

    Science.gov (United States)

    Jean, Gladys; Simard, Daphnee

    2011-01-01

    This descriptive inquiry-based study targeted second language (L2) high school students' (n = 2321) and teachers' (n = 45) beliefs and perceptions about grammar instruction, specifically about grammatical accuracy, corrective feedback, and diverse forms of grammar teaching and learning. Results showed only slight discrepancies between students'…

  5. Lattice dynamics of {alpha} boron and of boron carbide; Proprietes vibrationnelles du bore {alpha} et du carbure de bore

    Energy Technology Data Exchange (ETDEWEB)

    Vast, N

    1999-07-01

    The atomic structure and the lattice dynamics of {alpha} boron and of B{sub 4}C boron carbide have been studied by Density Functional Theory (D.F.T.) and Density Functional Perturbation Theory (D.F.P.T.). The bulk moduli of the unit-cell and of the icosahedron have been investigated, and the equation of state at zero temperature has been determined. In {alpha} boron, Raman diffusion and infrared absorption have been studied under pressure, and the theoretical and experimental Grueneisen coefficients have been compared. In boron carbide, inspection of the theoretical and experimental vibrational spectra has led to the determination of the atomic structure of B{sub 4}C. Finally, the effects of isotopic disorder have been modeled by an exact method beyond the mean-field approximation, and the effects onto the Raman lines has been investigated. The method has been applied to isotopic alloys of diamond and germanium. (author)

  6. 1000m depth boring at Inagawa, Hyogo prefecture. 1. Overviews; Hyogoken Inagawamachi ni okeru 1000m boring chosa. 1. Gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T.; Kusunose, K.; Cho, A.; Tosha, T. [Geological Survey of Japan, Tsukuba (Japan); Kiyama, T.; Yamada, F. [Mitsui Construction Co. Ltd., Tokyo (Japan); Aizawa, T. [Sancoh Consultants Co. Ltd., Tokyo (Japan)

    1996-05-01

    Various field experiments were carried out using a 1000m deep borehole at Inagawa town, about 10km north of the focus of the Hanshin-Awaji Great Earthquake and directly above the area where shallow earthquake activities have intermittently occurred. These experiments included stress measurement by hydraulic fracturing, hydrophone-aided VSP, permeability tests and observation of various types of logging. The laboratory experiments were also carried out, including measurement of various properties and stresses of the core samples. The stress-depth relationship, determined by the hydraulic fracturing method, shows that the stress gradient well coincides with the Western Japan standard at a depth up to 700m, whereas it is approximately twice as high as the standard at a depth of 946m, at which core disking and borehole break-out are clearly observed, and hence stresses conceivably concentrate locally. Orientation of the maximum horizontal compressive stress is E-W at a depth of around 600m, but greatly changes to NNW-SSE at a deeper position. 4 refs., 5 figs.

  7. 高硅铝合金无缸套发动机缸体缸孔珩磨加工数控机床关键技术研究%Research on Key Technologies of High-silicon Aluminum Alloy No-cylinder-liner Engine Block Cylinder Bore Honing CNC Machine Tool

    Institute of Scientific and Technical Information of China (English)

    余阿东; 王平俊; 李翔龙

    2016-01-01

    Based on high⁃silicon aluminum alloy no⁃cylinder⁃liner engine block bore materials grinding characteristics, a dual⁃spindle CNC honing machine tool was developed. In the machine tool, two⁃position two⁃spindle honing layout was used, it consisted of the following modules:spindle box, column, column glide, workpiece clamping table and so on. Spindle honing dual feed mechanism and honing oilstone double feed body were adopted. A closed loop control system based on motion control card was used. The system hardware platform was IPC and general industrial motion control card, based on the pneumatic differential pressure measuring honing online system, processing volume closed⁃loop control was achieved. The software platform was Windows system, VC++ development tool was used to program specialized processing procedures for the honing process.%基于高硅铝合金无缸套发动机缸体缸孔材料的磨削特点,开发了一种数控双主轴珩磨机床。该机床采用二工位双主轴的珩磨加工布局,由以下模块组成:主轴箱、立柱、立柱下滑台、工件装夹工作台等;采用主轴珩磨双进给机构及珩磨头油石双涨机构;采用基于运动控制卡的全闭环控制系统,系统硬件平台采用工控机和通用工业运动控制卡,运用基于差压式珩磨在线气动测量系统,实现加工量的闭环控制;软件平台采用Windows系统,采用VC++开发工具编制珩磨工艺加工程序。

  8. 不同小蠹类与天牛类引诱剂联用对蛀干甲虫的林间诱捕效果%Field efficacy of combinations of attractants for bark beetles and longicorn beetles in trapping wood-boring beetles

    Institute of Scientific and Technical Information of China (English)

    王义平; 郭瑞; 邓建宇; 张真

    2013-01-01

    Monochamus alternatus Hope is the primary vector for spreading pine wilt disease.Use of attractants in the control of M.alternatus population is effective and pollution-free.In this study,the field test was conducted to evaluate the attractiveness of M.alternatus attractant combined with six kinds of bark beetle attractants to M.alternatus adults.The results showed that there was no significant difference among the combinations of each of bark beetle attractants for Tomicus minor Hartig (3-carene-10-ol),Ips typographus Linnaeus (2-methyl-3-buten-2-ol),Scolytus multistriatus Marsham (4-methyl-3-heptanol),and T.piniperda Linnaeus (verbenol) with M.alternatus attractant (P < 0.05).The combinations of attractants for either Dendroctonus brevicomis LeConte (exo-brevicomin) or D.pseudotsugae (1-methylcyclohex-2-en-l-ol) with M.alternatus attractant were less attractive to M.alternatus.Compared with M.alternatus attractant used only,the combination of either D.brevicomis or D.pseudotsugae with M.alternatus attractant was also less attractive as indicated by the species and number of wood-boring beetle individuals captured.%松墨天牛Monochamus alternatus Hope是传播松材线虫病的主要媒介,引诱剂是抑制松墨天牛种群数量的无公害调控有效方式之一.本研究通过在中国浙江富阳的林间试验测定了6种小蠹类引诱剂与1种天牛引诱剂不同组合联用对松墨天牛成虫以及其他蛀干害虫的诱捕效果.结果表明:横坑切梢小蠹Tomicus minor引诱剂3-carene-10-ol、云杉八齿小蠹Ips typoyraphus引诱剂2-methyl-3-buten-2-ol、欧洲榆小蠹Scolytus multistriatus引诱剂4-methyl-3-heptanol和纵坑切梢小蠹T.piniperda引诱剂verbenol分别与松墨天牛引诱剂联用后,对松墨天牛的引诱效果无显著性差异(P<0.05).西部松大小蠹Dendroctonus brevicomis引诱剂exo-brevicomin或黄杉大小蠹D.pseudotsugae引诱剂1-methylcyclohex-2-en-l-ol与松墨天牛引诱剂联用后对松墨

  9. 地层水侵入对超临界CO2钻井井筒温度和压力的影响%Influences of formation water invasion on the well bore temperature and pressure in supercritical CO2 drilling

    Institute of Scientific and Technical Information of China (English)

    王海柱; 沈忠厚; 李根生

    2011-01-01

    Aiming to study the influence of formation water invasion on the well bore temperature and pressure in SC-CO2 (supercritical CO2) drilling with coiled tubing, this paper builds up a weilbore flow model with formation water invasion in SC-CO2 drilling with coiled tubing, based on the comprehensive investigation of the influence of viscosity, density, thermal conductivity, isobaric heat capacity and Joule-Thompson coefficient of SC-CO2. The wellbore temperature and pressure distribution were calculated by the method of coupling among these parameters. The results show that the bigger the rate of invaded formation water and the bigger the density of mixed fluid,the bigger the convective heat transfer coefficient in the annulus. Because of the .Joule-Thompson cooling effect caused by nozzle throttling, the annulus mixture fluid density increased abruptly and the convective heat transfer coefficient decreased abruptly at the well depth of about 1 900 m (about 10 m to bottom hole). Meanwhile the wellbore fluid temperature increased with the invasion rate of formation water, and the same Joule-Thompson cooling effect caused the wellbore fluid temperature to decrease abruptly at the well depth of about 1 900 m. Moreover, the wellbore annulus pressure increased with the increasing of invaded formation water quantity, butthe amplitude is not obvious.%为了研究sC-CO(超临界CO)连续油管钻井过程中地层水侵入对井筒温度和压力的影响,在综合考虑CO流体的黏度、密度、导热系数、热容、焦耳-汤姆逊系数等参数影响的基础上,建立了SC-CO连续油管钻井地层水侵入井筒流动模型,并采用各参数相互耦合的方法对井筒温度和压力分布进行了计算.结果表明,地层水侵入速度越大其混合流体密度越高,环空混合流体对流换热系数越大,但由于喷嘴节流产生的焦耳-汤姆逊冷却效应,在井深约1 900 m处(离井底约10 m处)环空混合流体密度突然增大、对流

  10. Mechanism of Load Transfer on Ultra-long and Large-Diameter Bored Piles at Thermal Power Plant Phase-Ⅱ in Hai Phong City of Vietnam%越南海防热电厂二期工程超长大直径灌注桩荷载传递机理试验研究

    Institute of Scientific and Technical Information of China (English)

    张利洁; 边智华; 景锋; 唐辉明; 杨喜庆; 叶红卫; 毕承

    2012-01-01

    The thermal power plant is located at Thuy-nguyen District, Haiphong city in Vietnam with an installed capacity of 2×300 MW. Since the power plant is located in a low land near the Gia River with developed karst geo-morphology and thick mucky soil strata on the top, the soil quality is too weak to meet the requirements of the foundation. Bored piles are planned to be used on the main construction area. Pile foundation test is performed in this project area. Mechanism of axial force transfer on the pile and the characteristics of load-settlement of the pile are analyzed. The results suggest that the ultimate bearing capacity of single pile could be 7000kN in this area. The axial force transfer on pile is influenced by many factors. Load on the pile top is transferred down gradually by lateral friction resistance which takes up a great proportion compared with the friction resistance on the pile end. Sediment thickness at the bottom of pile remarkably affects the pile top settlement and the ultimate bearing capacity of pile.%越南海防热电厂二期工程位于海防市(Hai Phong)水源镇(Thuy-nguyen),装机容量为2x300 MW.场地为Gia河边的低地,属于喀斯特地貌区,岩溶比较发育,上部存在较厚的淤泥质土层,土质较差,不能满足厂区上部结构对地基的要求,因此厂区主要建筑物的地基处理采用钻孔灌注桩.对该工程区桩基进行了检测试验,依据桩基试验实测数据,分析了桩身轴力的荷载传递机理以及桩的荷载-沉降特性.结果表明:该工程区的单桩极限承载力可取为7000 kN;桩身轴力的传递特性受多种因素影响,桩顶荷载主要通过桩侧摩阻力逐渐向下传递,具有明显的摩擦桩特点,桩侧摩阻力所占比重较大,而桩端阻力所占比重较小;桩底沉渣厚度显著影响桩顶沉降量与极限承载力.

  11. On the Memories of Kashing Canals and of the Hangchow Bore ——Reading the Sketches Written by Charles K. Edmunds and Others A Century Ago%品运河古韵,观钱塘怒涛,寻浙江记忆——解读美国传教士晏文士等人百年前的钱江观潮游记

    Institute of Scientific and Technical Information of China (English)

    沈弘

    2011-01-01

    "A Visit to the Hangchow Bore" in The Popular Science Monthly (1908) is one of Charles K. Edmunds' sketches written during his travels around China in early 20th century. It records in great details his observations of and reflections on what he saw along the canals between Shanghai and Haining, as well as the Hangchow Bore. Like other similar sketches by John Green and William R. Kahler during approximately the same period, it provides an objective reference to our understanding of the local culture in the regions of Jiaxing and Haining a century ago. Unfortunately these sketches were written either in English or in German, and in them there are many proper names and special terminology that need expli- cation. The present paper is an attempt in this direction.%美国传教士晏文士发表在《大众科学月刊》上的一篇海宁观潮连载文章,是他在中国各地旅行时细心观察和记录的成果之一。它详细记载了作者从上海至海宁的旅途见闻和在海宁观看钱江大潮的细节和感受。与同期的葛骆和葛利等其他两位外国人所写的钱江观潮游记一样,它为我们了解百年前的杭嘉湖地域文化提供了一个客观的参照。由于上述游记是用英文、德文等欧洲文字发表的,而且文章中有不少人名、地名和意思比较隐晦的专门术语,一般的读者难以看懂,需要有人对此加以翻译和解读。本文便是这样的一种尝试。

  12. Drinking speed using a valved Pat Saunders straw TM, wide bore straw and a narrow bore straw in school age children

    OpenAIRE

    Harding, C.; Aloysius, A.

    2011-01-01

    Background: To understand the nature of straw drinking in relation to a group of children with specific eating and drinking difficulties, it is first necessary to ascertain the range of normal function. Straw drinking is often recommended as a method that can support children with eating and drinking difficulties. Method: This study looked at straw drinking performance in a normal population of 125 children aged between 6 and 11 years of age. Three types of straws were used: a valved Pat ...

  13. On board or bored stiff? How to run effective board meetings.

    Science.gov (United States)

    Schneck, Lisa H

    2003-01-01

    Boards of directors meet to resolve problems or make decisions. To get the most out of your practice's board meetings, know when and why you need to meet, who needs to attend, how to run the meeting effectively and whom you represent.

  14. Sensitivity Analysis of Michelson Type Microwave Interferometry for the Measurement of Projectile In-Bore Motion

    Science.gov (United States)

    1982-01-01

    AND ADDRESS U.S. Army Ballistic Research Laboratory ATTN: DRDAR-BLI Aberdeen Proving Ground, MD 21005 10. PROGRAM ELEMENT, PROJECT. TASK AREA ...B. Brodman G. Del Coco K. Pfleger M.J. Schmitz DRDAR-SCM, E. Bloore J. Mulherin DRDAR-SCS, J. Blumer D. Brandt T. Hung S. Jacobson Dover...reports. 1. BRL Report Number 2. Does this report satisfy a need? (Comment on purpose, related project, or other area of interest for which report

  15. Cylindricity Error Measuring and Evaluating for Engine Cylinder Bore in Manufacturing Procedure

    OpenAIRE

    Qiang Chen; Xueheng Tao; Jinshi Lu; Xuejun Wang

    2016-01-01

    On-line measuring device of cylindricity error is designed based on two-point method error separation technique (EST), which can separate spindle rotation error from measuring error. According to the principle of measuring device, the mathematical model of the minimum zone method for cylindricity error evaluating is established. Optimized parameters of objective function decrease to four from six by assuming that c is equal to zero and h is equal to one. Initial values of optimized parameters...

  16. Calibration of Breech Erosion Gage for 5.56mm Chrome-Plated Bores

    Science.gov (United States)

    1975-12-01

    34 tft.. CantoiIlate Olft.) Ill TEUIy CLASS. (of ffile .oepot) Unclassified ISO . DECL ASSi VIC ATION’DOW94GRADING 16. DISTRIOUTION STATEMENT (of Wit9...6.3 8.9 13.4 7.6 7.3 6.3 6.2 7.1 26000 16.1 9.1 10.9 13.9 8.9 6.4 6.3 3.1 4.9 27000 12.4 8.4 11.2 13.1 8.3 6.5 7.3 3.4 4.3 28000 12.1 6.9 19.3 11.4

  17. Kinetics of Natural Attenuation: Review of the Critical Chemical Conditions and Measurements at Bore Scale

    Directory of Open Access Journals (Sweden)

    O. Atteia

    2002-01-01

    Full Text Available This paper describes the chemical conditions that should favour the biodegradation of organic pollutants. Thermodynamic considerations help to define the reaction that can occur under defined chemical conditions. The BTEX (benzene, toluene, ethylbenzene, and xylene degradation is focused on benzene, as it is the most toxic oil component and also because it has the slowest degradation rate under most field conditions. Several studies on benzene degradation allow the understanding of the basic degradation mechanisms and their importance in field conditions. The use of models is needed to interpret field data when transport, retardation, and degradation occur. A detailed comparison of two existing models shows that the limits imposed by oxygen transport must be simulated precisely to reach correct plumes shapes and dimensions, and that first-order kinetic approaches may be misleading. This analysis led us to develop a technique to measure directly biodegradation in the field. The technique to recirculate water at the borehole scale and the CO2 analysis are depicted. First results of biodegradation show that this technique is able to easily detect the degradation of 1 mg/l of hydrocarbons and that, in oxic media, a fast degradation rate of mixed fuel is observed.

  18. Manipulation et fonctionnalisation de nanotube : Application aux nanotubes de nitrure de bore.

    OpenAIRE

    2007-01-01

    Boron nitride nanotubes are new tubular materials which are structurally related to carbon nanotubes and are made of one or several rolled-up hexagonal boron nitride sheets. Nanoelectronics, material science and medicine are among the potential application fields of these tubular structures. Single-walled boron nitride nanotubes (SWBNNTs) are being produced by continuous LASER ablation at the ONERA. The crude samples contain SWBNNTs and boron nitride cages but are also contaminated by boric a...

  19. The Affects of Not Reading: Hating Characters, Being Bored, Feeling Stupid

    Science.gov (United States)

    Poletti, Anna; Seaboyer, Judith; Kennedy, Rosanne; Barnett, Tully; Douglas, Kate

    2016-01-01

    This article brings recent debates in literary studies regarding the practice of close reading into conversation with Derek Attridge's idea of "readerly hospitality" (2004) to diagnose the problem of students in undergraduate literary studies programme not completing set reading. We argue that the method of close reading depends on…

  20. Mechanics of Cutting and Boring. Part 3. Kinematics of Continuous Belt Machines,

    Science.gov (United States)

    BOREHOLES, * CUTTING TOOLS , *ICE PENETRATION, *DRILLING MACHINES, *ROAD BUILDING EQUIPMENT, KINEMATICS, PERFORMANCE(ENGINEERING), ROCK, BELTS, EXCAVATION, ARCTIC REGIONS, PERMAFROST, SHALE, SAWS, TRENCHING.

  1. Ballet Doesn't Have to Be Boring: Engaging Students in the Creative Process

    Science.gov (United States)

    Scheff, Helene

    2005-01-01

    For many years, the author has incorporated creative process into the way she teaches ballet class. The author shares the philosophical, practical, and artistic reasons for the creative process in ballet classes. She also shares the rationale and how this practice developed over time.

  2. Zachsia zenkewitschi (Teredinidae), a Rare and Unusual Seagrass Boring Bivalve Revisited and Redescribed

    Science.gov (United States)

    Shipway, J. R.; O’Connor, R.; Stein, D.; Cragg, S. M.; Korshunova, T.; Martynov, A.; Haga, T.; Distel, D. L.

    2016-01-01

    The sea-grass borer Zachsia zenkewitschi belongs to a group of economically and ecologically important bivalves, commonly referred to as shipworms. The sole recognized representative of the genus Zachsia, this species displays an unusual life history and reproductive strategy that is now understood to include: environmental sex determination of free swimming larvae, extreme sexual and size dimorphism between males and females, internal fertilization, maintenance of often large harems of male dwarfs within a specialized cavity of the female mantle, and complex maternal care of larvae in specialized brood pouches within the gill. It is also the only shipworm species known to burrow in sea grass rhizomes rather than terrestrial wood. Although Z. zenkewitschi is rare and little studied, understanding of its biology and anatomy has evolved substantially, rendering some aspects of its original description inaccurate. Moreover, no existing type specimens are known for this species. In light of these facts, we designate a neotype from among specimens recently collected at the type location, and undertake a re-description of this species, accounting for recent reinterpretation of its life history and functional anatomy. PMID:27171209

  3. Investigations on the geothermal state of the ICDP COSC-1 well bore

    Science.gov (United States)

    Löwe, Richard; Pascal, Christophe; Renner, Jörg

    2016-04-01

    In 2014 the first well of the Collisional Orogeny in the Scandinavian Caledonides (COSC) ICDP project was drilled near Åre in west central Sweden. The well penetrates the Seve Nappe complex, a result of subduction/exhumation processes during the collision of Baltica and Laurentia ~ 400 Myrs ago (Gee et al. 2010). To gain a more detailed understanding of the geothermal state of fossil mountain belts and cratonic areas, it is necessary to study present-day heat transfer in the earth's crust in appropriate deep boreholes. Constraining the heat transfer requires temperature measurements in boreholes and determination of thermal properties of the rocks present. The specific object of our study is to derive a local thermal model providing the pristine thermal state and quantifying transient effects, i.e. paleoclimatic and convective effects, on the local geotherm. The outstanding core recovery (~ 100%) of the 2495.8 m (MD) deep well in combination with extensive wireline logging campaigns provide an exceptional basis for a broad range of core measurements and well log correlations. A total of 105 core samples, representing all major lithologies, were carefully selected for laboratory investigations, such as determining heat capacity, thermal conductivity, and thermal diffusivity. Density and thermal conductivity were determined for each of the 105 core samples under ambient pressure and unsaturated conditions. The thermal conductivity was measured using the optical scanning method (Popov et al. 1985) providing a first-order estimate of thermal properties along the cores' surfaces. Based on these preliminary measurements, a thermal conductivity profile was constructed, showing a steep increase towards the lower section of the well. For the first ~ 2000 m the average thermal conductivity amounts to 2.5±0.6 W/(m.K) and increases to 4.1±1 W/(m.K) in the lower section of the well. In addition, spectral gamma ray logs were used to determine the amount of radiogenic heat production (Rybach, 1988). The integrated heat production within the well is merely low and amounts to ~3.3 mW/m². Three temperature logs were measured about one week, one month, and one year after drilling. The observed gradual slowdown in temperature recovery suggests that the latest log was probably measured very close to thermal equilibrium. Furthermore, the latest temperature log appears to show a typical curvature reflecting sudden global warming at the Pleistocene-Holocene transition. Based on the latest temperature log an uncorrected average thermal gradient of ~21 °C/km is tentatively proposed. References: Gee, D. G.; Juhlin, C.; Pascal, C.; Robinson, P. (2010): Collisional Orogeny in the Scandinavian Caledonides (COSC). In GFF 132 (1), pp. 29-44. Rybach, L. (1988): Determination of Heat Production Rate. In R. Haenel, L. Rybach, L. Stegena (Eds.): Handbook of terrestrial heat-flow density determination. Guidelines and recommendations of the International Heat Flow Commission, pp. 125-142. Popov, Y. A.; Berezin, V. V.; Semenov, V. G.; Korostelev V. M. (1985): Complex Detailed Investigations on the Thermal Properties of Rocks on the Basis of a Moving Point Source. In Izvestiya, Earth Physics 21 (1), pp. 64-70.

  4. Prediction of response and damaged length of a subsea pipeline after a full bore rupture

    OpenAIRE

    Mashayekh, Kourosh

    2012-01-01

    The combination of oil and gas reservoirs in sea areas with high shipping traffic brings some challenges for engineers. One of these challenges is related to subsea pipeline systems specially where water depth is classified as shallow or intermediate. Due to large number of vessels passing the area with shallow water depth, interaction between anchors of these vessels and the offshore pipeline can occur. If a dragging anchor hits and subsequently hooks the pipeline, the pipeline could be rupt...

  5. Tunnel Boring Machine Technology for a Deeply Based Missile System. Volume I, Application Feasibility. Part 1.

    Science.gov (United States)

    1980-08-01

    chart 5% Calcareous cement 5% Classification: Argillized , cherty, micaceous, calcareous felds- pathic sandstone Origin: Alluvium deposits Physical...Texture: Fine medium qrained sand with clay clasts, well sorted, argillized calcareous cementing, medium porosity and permeability Mineralogical...Composition: Quartz sand 75% Feldspathic sand 15% Clay clasts 5% Calcareous cement 5. Classification: Argillized , feldspathic w/clay clasts, calcareous

  6. Cloud hole-boring with long pulse CO sub 2 lasers

    Energy Technology Data Exchange (ETDEWEB)

    Quigley, G.P.; Webster, R.B.; York, G.W.

    1990-01-01

    Chemically generated CO{sub 2} laser pulses at 10.6 {mu}m have been used to clear a 5 cm diameter hole through a stratus-like cloud in a laboratory cloud chamber. The results show that 100% clearing can be achieved. The mechanism is shown to be droplet shattering followed by evaporation. Under the conditions of the experiment, the channel closure is dominated by turbulent mixing and not droplet recondensation. 14 refs., 9 figs.

  7. Analysis of the Tunnel Boring Machine Advancement on the Bologna-Florence Railway Link

    Directory of Open Access Journals (Sweden)

    M. Cardu

    2009-01-01

    Full Text Available Problem statement: The high-velocity railway link between Bologna and Firenze (Italy is today under construction and several tunnels have to be excavated for this purpose, some of these using TBMs. A small diameter tunnel, named Cunicolo ginori, was realized by TBM parallel to a large railway tunnel (Vaglia, at the distance of only 35 m. Approach: The Vaglia tunnel had been excavated by conventional methods and provided, thanks to a detailed survey and a systematic geotechnical monitoring (rock quality evaluation and convergence measurements the characterization data of the crossed rock mass; moreover the TBM performance data in Cunicolo ginori were continuously monitored. A tunnel stretch, 587 m long, was recorded and the analysis of the data from both surveys allowed to correlate the geomechanical parameters of the rock-mass to the TBM performances (net advancement rate, thrust, specific energy. Results: Based on this large amount of data a new system to predict the net TBM advancement rate for a tunnel in rock masses of known geological and geomechanical characteristics was then developed. Also the Utilization Coefficient (CU can be correlated to the rock quality Indices: The net advance rate and the utilization coefficient provide a mean to foresee the gross advancement rate and to evaluate the suitability of a machine for the excavation of a tunnel. Conclusion: In this study, an analysis had been carried out on about 587 m of a service tunnel, excavated by a TBM in a flysch formation.

  8. Design of concrete structures for durability. Example: Chloride penetration in the lining of a bored tunnel

    NARCIS (Netherlands)

    Siemes, A.J.M.

    1998-01-01

    The present design method for durability of concrete is based on a set of rules that give no objective in-sight in the service life to expect from the concrete structure. An objective comparison between different durability measures is therefor not possible. Especially if the lack of durability can

  9. Testing of the large bore single aperture 1-meter superconducting dipoles made with phenolic inserts

    CERN Document Server

    Boschmann, H; Dubbeldam, R L; Kirby, G A; Lucas, J; Ostojic, R; Russenschuck, Stephan; Siemko, A; Taylor, T M; Vanenkov, I; Weterings, W

    1998-01-01

    Two identical single aperture 1-metre superconducting dipoles have been built in collaboration with HMA Power Systems and tested at CERN. The 87.8 mm aperture magnets feature a single layer coil wound using LHC main dipole outer layer cable, phenolic spacer type collars, and a keyed two part structural iron yoke. The magnets are designed as models of the D1 separation dipole in the LHC experimental insertions, whose nominal field is 4.5 T at 4.5 K. In this report we present the test results of the two magnets at 4.3 K and 1.9 K.

  10. Electrical heating of well bore area in wells of Uzbekistan oil region

    Energy Technology Data Exchange (ETDEWEB)

    Alidzhanov, G.A.; Osmanov, M.T.; Simkin, E.M.; Sheinman, A.B.

    1966-11-01

    The productivity of many wells in the Fergan area, Uzbekistan, decreased to 1/6 of initial value in the first year of production. Stimulation with hot gasoline or acid was only moderately successful. Best results were obtained by installing an electrical heater opposite the pay zone. In a typical case, well No. 464 (562 m deep) was completed in 1962 with an initial production of 10 tons/day. After 4 acid treatments, production was 2.5 tons/day in 1964, bottomhole temperature was 33$C, and pressure was 20 kg/cmU2D. A 10.5-kw electric heater was used for 3 days to raise bottomhole temperature to 52$C. Production increased to 3.5 tons/day and remained at that level for a month. In a second treatment a 21-kw heater increased bottomhole temperature to 120$C, whereupon production increased to 4.3 tons/day, and remained at that level for 3.5 months. Similar results were obtained in many other wells. Electrical method of stimulation is more economical than other methods in this area.

  11. A device for monitoring and calibrating bore hole sonic logging devices

    Energy Technology Data Exchange (ETDEWEB)

    Gufranov, M.G.

    1980-06-05

    The device contains a hollow standarized pipe. In order to increase the effectiveness and monitoring accuracy, part of the pipe is built with holes in its walls. The shape and placement of the holes is established depending on the necessary test ranges of the working characteristics of the devices, accounting for the diameter of the pipe and the measurement base of the device. The holes in the walls of the pipe are circular in shape and are placed uniformly in rows in accordance with set relationships.

  12. Fouling and Boring of Glass Reinforced Plastic - Balsa Blocks in a Tropical Marine Environment,

    Science.gov (United States)

    1983-03-01

    only fouled below the water line, mainly by diminutive algae and a slime film of undetermined composition (possibly bacteria, diatoms and organics... composition . The GRP performed as any hard, smooth, non-toxic substratum immersed in the sea and rapidly accrued a cover of diverse organisms. c. Minahunter... Plastique and suppliid by Australian Klegecell Co., Sydney. Nominal density 130 kg/m 3. Balsa wood imported from Papua-New Guinea and supplied by Australian

  13. A 1 T, 0.33 m bore superconducting magnet operating with cryocoolers at 12 K

    NARCIS (Netherlands)

    Laan, van der M.T.G.; Tax, R.B.; Kate, ten H.H.J.; Klundert, van de L.J.M.

    1992-01-01

    The application of small cryocoolers to cooling a superconducting magnet at 12 K has important advantages, especially for small and medium-size magnets. Simple construction and a helium-free magnet system were obtained. The demonstration magnet developed is a six-coil system with a volume of 75 L an

  14. Why Kids Need to Be Bored: A Case Study of Self-Reflection and Academic Performance

    Science.gov (United States)

    Williams, James D.

    2006-01-01

    This case study involved 3 middle school students in an assessment of the influence of self-reflection on general academic performance. It was hypothesized that increased self-reflection would have a positive influence on academic performance as measured by grades on tests, writing assignments, and homework. The participants were ages 13.4, 13.5,…

  15. Using a Bore Sight Camera as an AR&D Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase II SBIR project will provide real time, relative six Degree of Freedom (6DoF) information to the crew of the ORION for docking. Our technical innovation...

  16. Using a Bore Sight Camera as an AR&D Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Orion requires a rendezvous and docking sensor to provide relative navigation information during proximity operations and docking. In order to dock, the sensor must...

  17. Laser-Hole Boring into Overdense Plasmas Measured with Soft X-Ray Laser Probing

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, K. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Kodama, R. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Tanaka, K. A. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Hashimoto, H. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Kato, Y. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Mima, K. [Institute of Laser Engineering, Osaka University, Yamada Oka 2-6, Suita, Osaka 565-0871, (Japan); Weber, F. A. [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Barbee, T. W. Jr. [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Da Silva, L. B. [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)

    2000-03-13

    A laser self-focused channel formation into overdense plasmas was observed using a soft x-ray laser probe system with a grid image refractometry (GIR) technique. 1.053 {mu}m laser light with a 100 ps pulse duration was focused onto a preformed plasma at an intensity of 2x10{sup 17} W /cm{sup 2} . Cross sections of the channel were obtained which show a 30 {mu}m diameter in overdense plasmas. The channel width in the overdense region was kept narrow as a result of self-focusing. Conically diverging density ridges were also observed along the channel, indicating a Mach cone created by a shock wave due to the supersonic propagation of the channel front. (c) 2000 The American Physical Society.

  18. Mitigation of high-frequency pulsations, using Multi Bore Restriction Orifices

    NARCIS (Netherlands)

    Lier, L.J. van; Korst, H.J.C.

    2007-01-01

    In reciprocating fluid displacement systems, a trend toward high-speed machinery and application of stepless reverse-flow capacity control system is observed. Badly designed compression systems may cause excessive high-frequency noise and vibration levels, which are a risk from a structural integrit

  19. Very deep borehole. Deutag's opinion on boring, canister emplacement and retrievability

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Tim [Well Engineering Partners BV, The Hague (Netherlands)

    2000-05-01

    An engineering feasibility study has been carried out to determine whether or not it is possible to drill the proposed Very Deep Borehole concept wells required by SKB for nuclear waste disposal. A conceptual well design has been proposed. All aspects of well design have been considered, including drilling tools, rig design, drilling fluids, casing design and annulus isolation. The proposed well design is for 1168.4 mm hole to be drilled to 500 m. A 1066.8 mm outer diameter (OD) casing will be run and cemented. A 1016 mm hole will be drilled to approximately 2000 m, where 914.4 mm OD casing will be run. This annulus will be sealed with bentonite slurry apart from the bottom 100 m which will be cemented. 838.2 mm hole will be drilled to a final depth of 4000 m, where 762 mm OD slotted casing will be run. All the hole sections will be drilled using a downhole hammer with foam as the drilling fluid medium. Prior to running each casing string, the hole will be displaced to mud to assist with casing running and cementing. The waste canisters will be run on a simple J-slot tool, with integral backup system in case the J-slot fails. The canisters will all be centralised. Canisters can be retrieved using the same tool as used to run them. Procedures are given for both running and retrieving. Logging and testing is recommended only in the exploratory wells, in a maximum hole size of 311.1 mm. This will require the drilling of pilot holes to enable logging and testing to take place. It is estimated that each well will take approximately 137 days to drill and case, at an estimated cost of 4.65 Meuro per well. This time and cost estimate does not include any logging, testing, pilot hole drilling or time taken to run the canisters. New technology developments to enhance the drilling process are required in recyclable foam systems, in hammer bit technology, and in the development of robust under-reamers. It is the authors conclusion that it is possible to drill the well with currently existing technology, although it represents one of the biggest challenges to be presented to the drilling industry.

  20. Zinc complexes as fluorescent chemosensors for nucleic acids: new perspectives for a "boring" element.

    Science.gov (United States)

    Terenzi, Alessio; Lauria, Antonino; Almerico, Anna Maria; Barone, Giampaolo

    2015-02-28

    Zinc(II) complexes are effective and selective nucleic acid-binders and strongly fluorescent molecules in the low energy range, from the visible to the near infrared. These two properties have often been exploited to quantitatively detect nucleic acids in biological samples, in both in vitro and in vivo models. In particular, the fluorescent emission of several zinc(II) complexes is drastically enhanced or quenched by the binding to nucleic acids and/or upon visible light exposure, in a different fashion in bulk solution and when bound to DNA. The twofold objective of this perspective is (1) to review recent utilisations of zinc(II) complexes as selective fluorescent probes for nucleic acids and (2) to highlight their novel potential applications as diagnostic tools based on their photophysical properties.

  1. When curiosity breeds intimacy: Taking advantage of intimacy opportunities and transforming boring conversations

    Science.gov (United States)

    Kashdan, Todd B.; McKnight, Patrick E.; Fincham, Frank D.; Rose, Paul

    2012-01-01

    Curious people seek knowledge and new experiences. In three studies, we examined whether, when, and how curiosity contributes to positive social outcomes between unacquainted strangers. Study 1 showed that curious people expect to generate closeness during intimate conversations but not during small-talk; less curious people anticipated poor outcomes in both situations. We hypothesized that curious people underestimate their ability to bond with unacquainted strangers during mundane conversations. Studies 2 and 3 showed that curious people felt close to partners during intimate and small-talk conversations; less curious people only felt close when the situation offered relationship-building exercises. Surprise at the pleasure felt during this novel, uncertain situation partially mediated the benefits linked to curiosity. We found evidence of slight asymmetry between self and partner reactions. Results could not be attributed to physical attraction or positive affect. Collectively, results suggest that positive social interactions benefits from an open and curious mindset. PMID:22092143

  2. Design of a bore sight camera for the lineate image near ultraviolet spectrometer (LINUS)

    OpenAIRE

    Cabezas, Rodrigo

    2004-01-01

    Approved for public release; distribution is unlimited. The Lineate Image Near Ultraviolet Spectrometer (LINUS) is a spectral imager that works in the ultraviolet region of the spectrum. This thesis describes the latest of several steps in the development of this instrument. Due to the narrow field of view of the instrument, 2.5 x 0.5 degrees, an accurate pointing method is necessary; also, a scheme of quality evaluation of the post-processed spectral image is desirable. A way to achieve...

  3. Variability of internal frontal bore breaking above Opouawe Bank methane seep area (New Zealand)

    NARCIS (Netherlands)

    van Haren, H.; Greinert, J.

    2013-01-01

    Large internal wave breaking is observed exceeding a vertical array of 61 high-resolution temperature sensors at 1 m intervals between 7 and 67 m above the bottom. The array was moored for 5 days at 969 m of Opouawe Bank, New Zealand, a known methane seep area. As breaking internal waves dominate se

  4. "I No Say You Say Is Boring": The Development of Pragmatic Competence in L2 Apology

    Science.gov (United States)

    Chang, Yuh-Fang

    2010-01-01

    While the number of studies on pragmatic development has been increasing since Kasper and Schmidt's call for more research into this under-researched area (e.g., [Barron, A., 2003. Acquisition in Interlanguage Pragmatics: Learning How to do Things with Words in a Study Abroad Context. Benhamins, Amsterdam; Achiba, M., 2003. Learning to Request in…

  5. The Study of Upper Ocean Stratification that Controls Propagation of Internal Tidal Bores in Coastal Areas

    Science.gov (United States)

    2012-06-01

    internal waves cause sediment erosion at the seafloor resulting in substantial mixing and suspension of material in the water column. 2. Internal... erosion from strong turbulent shear stress caused by nonlinear internal waves and low-frequency currents. 7 3. Internal Nepheloid Layers...signature is present at depths near the “mud belt” due to the fluvial material found at this location. B. RECOMMENDATIONS The high-resolution

  6. Are buffers boring? Uniqueness and asymptotical stability of traveling wave fronts in the buffered bistable system.

    Science.gov (United States)

    Tsai, Je-Chiang; Sneyd, James

    2007-04-01

    Traveling waves of calcium are widely observed under the condition that the free cytosolic calcium is buffered. Thus it is of physiological interest to determine how buffers affect the properties of calcium waves. Here we summarise and extend previous results on the existence, uniqueness and stability of traveling wave solutions of the buffered bistable equation, which is the simplest possible model of the upstroke of a calcium wave. Taken together, the results show that immobile buffers do not change the existence, uniqueness or stability of the traveling wave, while mobile buffers can eliminate a traveling wave. However, if a wave exists in the latter case, it remains unique and stable.

  7. Predator-prey interactions between shell-boring beetle larvae and rock-dwelling land snails

    NARCIS (Netherlands)

    Baalbergen, Els; Helwerda, Renate; Schelfhorst, Rense; Castillo Cajas, Ruth F.; van Moorsel, Coline H. M.; Kundrata, Robin; Welter-Schultes, Francisco W.; Giokas, Sinos; Schilthuizen, Menno

    2014-01-01

    Drilus beetle larvae (Coleoptera: Elateridae) are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae) species in Greece. We observe that Drilus species may be

  8. The boring billion? – Lid tectonics, continental growth and environmental change associated with the Columbia supercontinent

    Directory of Open Access Journals (Sweden)

    Nick M.W. Roberts

    2013-11-01

    Full Text Available The evolution of Earth's biosphere, atmosphere and hydrosphere is tied to the formation of continental crust and its subsequent movements on tectonic plates. The supercontinent cycle posits that the continental crust is periodically amalgamated into a single landmass, subsequently breaking up and dispersing into various continental fragments. Columbia is possibly the first true supercontinent, it amalgamated during the 2.0–1.7 Ga period, and collisional orogenesis resulting from its formation peaked at 1.95–1.85 Ga. Geological and palaeomagnetic evidence indicate that Columbia remained as a quasi-integral continental lid until at least 1.3 Ga. Numerous break-up attempts are evidenced by dyke swarms with a large temporal and spatial range; however, palaeomagnetic and geologic evidence suggest these attempts remained unsuccessful. Rather than dispersing into continental fragments, the Columbia supercontinent underwent only minor modifications to form the next supercontinent (Rodinia at 1.1–0.9 Ga; these included the transformation of external accretionary belts into the internal Grenville and equivalent collisional belts. Although Columbia provides evidence for a form of ‘lid tectonics’, modern style plate tectonics occurred on its periphery in the form of accretionary orogens. The detrital zircon and preserved geological record are compatible with an increase in the volume of continental crust during Columbia's lifespan; this is a consequence of the continuous accretionary processes along its margins. The quiescence in plate tectonic movements during Columbia's lifespan is correlative with a long period of stability in Earth's atmospheric and oceanic chemistry. Increased variability starting at 1.3 Ga in the environmental record coincides with the transformation of Columbia to Rodinia; thus, the link between plate tectonics and environmental change is strengthened with this interpretation of supercontinent history.

  9. An Analysis of Bore Surface Temperatures in Electrothermal-Chemical Guns

    Science.gov (United States)

    1991-10-01

    Time and Space-Dependent Boundary Conditions." Journal of Heat Transfer, Trans. ASME, series C, vol. 96, no. 3, pp. 300-306, August 1974. Eckert, E. R...Department of the Navy, CSEA 06 KR12 ATTN: CDR Craig Dampier 1 GT Devices, Inc. Washington, DC 20362-5101 ATTN: Dr. Neils Winsor 5705A General Washington Drive

  10. Boring Information and Subsurface Data Base Package User’s Guide.

    Science.gov (United States)

    1984-09-01

    l F -3 7F - 2 1Y 1 U 3. T. 2 F1’--I F 4 -FEST- F,-1rE *~7 1 . ESTR - I -IL’’ 1 2 A. T F- E:7 * 7 T)*i ES l 2) 1-’E M 6FI- I; 2 6 𔄁.D L fO.W -ELLYV...8217 .’ rilk.I tiE 1 NPUT i TNFI, $- # D NAME DATA VALUE 7 ..... ES N-NAMF .: . INDEX -’ ST-1ATE . . 04/10/ 1979 TESI -MAT .. SC SAND . - . . TE T .-ELEV .. 2.5

  11. Bored boys, graffiti, and YouTube - tracing recent groundwater level changes in a Saudi Arabian cave

    Science.gov (United States)

    Michelsen, Nils; Dirks, Heiko; Schulz, Stephan; Kempe, Stephan; Schüth, Christoph

    2015-04-01

    The Dahl Hith cave is located approximately 30 km southeast of Riyadh, the capital of Saudi Arabia. In the past decades, the groundwater table exposed inside the cave became subject to appreciable changes. After a decline due to agricultural water abstraction for irrigation purposes, the water table exhibited a rapid rise in the last few years. Considering that most of the aquifers of the country show a depletion of the largely fossil groundwater, the mentioned rise is quite unusual. The area does not host an observation well, i.e., reliable data on the piezometric changes is hitherto not available. Hence, two uncommon data sources were used to reconstruct the water level changes: (1) YouTube videos and (2) graffiti inscriptions. (1) The cave is frequently visited by locals and expats from Riyadh and many visitors are willing to share their cave adventures on YouTube. Identifying certain reference points in the uploaded videos (e.g. specific boulders, cave graffiti) and estimating their position relative to the water table allows for an approximate reconstruction of the recent groundwater rise. Information on the observation time is derived from the uploading date. Occasionally, also the exact date of the visit is provided as part of the footage description. (2) Some people documented their visit by graffiti inscriptions. These do not only serve as a marker in the videos, but also contain genuine data on historic water levels: if written on parts of the cave wall, which are only accessible from the water, they indicate the water level at the time of their creation. Fortunately, some graffiti also feature the date of the visit. In order to improve the reliability of the water level estimations, measurements conducted in the course of own site visits in the past few years were considered for the evaluation. Also photographs taken during these surveys helped to improve the quality of the water level reconstruction. The described "Youtube Approach" could be interpreted as a citizen science project with citizens being unaware of their participation. It illustrates the occasional need for creative solutions in data-scarce settings.

  12. Vibrations due to a test train at variable speeds in a deep bored tunnel embedded in London clay

    Science.gov (United States)

    Degrande, G.; Schevenels, M.; Chatterjee, P.; Van de Velde, W.; Hölscher, P.; Hopman, V.; Wang, A.; Dadkah, N.

    2006-06-01

    This paper reports on the results of in situ vibration measurements that have been performed within the frame of the CONVURT project at a site in Regent's Park on the Bakerloo line of London Underground during 35 passages of a test train at a speed between 20 and 50 km/h. Vibration measurements have been performed on the axle boxes of the test train, on the rails, on the tunnel invert and tunnel wall, and in the free field, both at the surface and at a depth of 15 m. Measurements have also been made on floors and columns of two buildings in a row of Regency houses at a distance of 70 m from the tunnel. Prior to these vibration measurements, the dynamic soil characteristics have been determined by in situ and laboratory testing. Rail and wheel roughness have been measured and the track characteristics have been determined by rail receptance and wave decay measurements. Time histories and one-third octave band RMS spectra of the measured velocities are discussed and the variation of the peak particle velocity and the frequency content as a function of the train speed and the distance to the tunnel are elaborated.

  13. Thermal-Induced Errors Prediction and Compensation for a Coordinate Boring Machine Based on Time Series Analysis

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2014-01-01

    Full Text Available To improve the CNC machine tools precision, a thermal error modeling for the motorized spindle was proposed based on time series analysis, considering the length of cutting tools and thermal declined angles, and the real-time error compensation was implemented. A five-point method was applied to measure radial thermal declinations and axial expansion of the spindle with eddy current sensors, solving the problem that the three-point measurement cannot obtain the radial thermal angle errors. Then the stationarity of the thermal error sequences was determined by the Augmented Dickey-Fuller Test Algorithm, and the autocorrelation/partial autocorrelation function was applied to identify the model pattern. By combining both Yule-Walker equations and information criteria, the order and parameters of the models were solved effectively, which improved the prediction accuracy and generalization ability. The results indicated that the prediction accuracy of the time series model could reach up to 90%. In addition, the axial maximum error decreased from 39.6 μm to 7 μm after error compensation, and the machining accuracy was improved by 89.7%. Moreover, the X/Y-direction accuracy can reach up to 77.4% and 86%, respectively, which demonstrated that the proposed methods of measurement, modeling, and compensation were effective.

  14. Analysis of the temporal and spatial dependence of the eddy current fields in a 40-cm bore magnet.

    Science.gov (United States)

    Robertson, S; Hughes, D G; Liu, Q; Allen, P S

    1992-05-01

    Eddy current fields, generated in an animal-size superconducting NMR magnet by a nominally rectangular pulsed transverse gradient applied in the vertical direction, have been studied by measuring the offset frequency of the proton NMR signal obtained from a small spherical sample. Measurements were made, after various time delays, at nine different locations in the sample space. Analysis of the data shows that the time-dependent fields at all nine locations are quite well accounted for by the superposition of only four independent exponentially decaying components that have time constants in the range from 9 to 400 ms. Two of these were found to be caused by eddy currents generated in the magnet structure. They generate primarily linear gradients, though one of them also produces a B0 shift, indicating a significant asymmetry about the isocenter of the conducting structure in which the eddy current flows. The other two exponentially decaying components, which had very different time constants from the eddy currents and also initial amplitudes of the opposite sign, were generated by the preemphasis unit. This calls into question the procedure used to adjust the preemphasis unit and an alternative method is proposed.

  15. North American Lauraceae: Terpenoid emissions, relative attraction and boring preferences of redbay ambrosia beetle, Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    The invasive redbay ambrosia beetle, Xyleborus glabratus, is the primary vector of Raffaelea lauricola, a symbiotic fungus and the etiologic agent of laurel wilt. This lethal disease has caused severe mortality of redbay (Persea borbonia) and swampbay (P. palustris) trees in the southeastern USA, t...

  16. Measurements of laser-hole boring into overdense plasmas using x-ray laser refractometry(invited)

    OpenAIRE

    1999-01-01

    Copyright 1999 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Review of Scientific Instruments, 70(1), 543-548, 1986 and may be found at http://dx.doi.org/10.1063/1.1149380

  17. New records of Fungiacava eilatensis Goreau et al., 1968 (Bivalvia, Mytilidae) boring into Indonesian mushroom corals (Scleractinia, Fungiidae)

    NARCIS (Netherlands)

    Hoeksema, B.W.; Kleemann, K.

    2002-01-01

    New observations on endoparasites in mushroom corals at South Sulawesi and Bali resulted in eight coral host records of the mytilid bivalve Fungiacava eilatensis Goreau et al., 1968, bringing the total to 14. The host corals were observed in various habitats, most frequently on sandy substrates. The

  18. Lithophaga (Bivalvia, Mytilidae), including a new species, boring into mushroom corals (Scleractinia, Fungiidae) of South Sulawesi, Indonesia

    NARCIS (Netherlands)

    Kleemann, K.; Hoeksema, B.W.

    2002-01-01

    Bivalve species of the mytilid genus Lithophaga, including a new one, are recorded from Indonesian mushroom corals (Scleractinia, Fungiidae). True associations with live hosts including L. laevigata, L. lessepsiana, L. lima, L. punctata spec. nov., and L. simplex, while specimens of L. malaccana and

  19. Do posture correction exercises have to be boring? Using unstable surfaces to prevent poor posture in children

    OpenAIRE

    Agnieszka Jankowicz-Szymanska; Edyta Mikolajczyk

    2016-01-01

    Introduction: Poor posture in children is a common problem. It appears most often in early school-age children and, if not corrected, progresses quickly as they mature. Aim of the research: To find a method that can prevent poor posture, is effective and attractive for children, and can be used on a wide scale in state schools. Material and methods : Seventy-seven first year pupils were tested at the beginning and at the end of the school year. Nineteen children undertook correc...

  20. Do posture correction exercises have to be boring? Using unstable surfaces to prevent poor posture in children

    Directory of Open Access Journals (Sweden)

    Agnieszka Jankowicz-Szymanska

    2016-07-01

    Full Text Available Introduction: Poor posture in children is a common problem. It appears most often in early school-age children and, if not corrected, progresses quickly as they mature. Aim of the research: To find a method that can prevent poor posture, is effective and attractive for children, and can be used on a wide scale in state schools. Material and methods : Seventy-seven first year pupils were tested at the beginning and at the end of the school year. Nineteen children undertook corrective exercises using unstable surfaces; 41 children sat on sensorimotor pillows during classes; and 17 children were the control group. Body mass and body height were measured. Body mass index was calculated. The symmetry of the position of selected skeletal points was assessed: the acromions, lower angles of the scapulas, apexes of the iliac crests, antero-superior iliac spine, and postero-superior iliac spine using a Duometer electronic device. The differences between the groups and changes between the first and second study for each group were estimated. Results : In the first study there were no significant differences in quality of posture. In the second study a significant improvement was noted in symmetry of the shoulders, scapulas, and pelvis in children who sat on sensorimotor pillows, as well as the position of the iliac crests and iliac spines in children exercising regularly on unstable surfaces. Conclusions: Exercises using unstable surfaces and sitting on sensorimotor pillows during classes might be an effective alternative to traditional posture correction exercises.

  1. From boring to scoring - a collaborative serious game for learning and practicing mathematical logic for computer science education

    Science.gov (United States)

    Schäfer, Andreas; Holz, Jan; Leonhardt, Thiemo; Schroeder, Ulrik; Brauner, Philipp; Ziefle, Martina

    2013-06-01

    In this study, we address the problem of low retention and high dropout rates of computer science university students in early semesters of the studies. Complex and high abstract mathematical learning materials have been identified as one reason for the dropout rate. In order to support the understanding and practicing of core mathematical concepts, we developed a game-based multitouch learning environment in which the need for a suitable learning environment for mathematical logic was combined with the ability to train cooperation and collaboration in a learning scenario. As application domain, the field of mathematical logic had been chosen. The development process was accomplished along three steps: First, ethnographic interviews were run with 12 students of computer science revealing typical problems with mathematical logic. Second, a multitouch learning environment was developed. The game consists of multiple learning and playing modes in which teams of students can collaborate or compete against each other. Finally, a twofold evaluation of the environment was carried out (user study and cognitive walk-through). Overall, the evaluation showed that the game environment was easy to use and rated as helpful: The chosen approach of a multiplayer game supporting competition, collaboration, and cooperation is perceived as motivating and "fun."

  2. DRILL WEAR DURING THE BORING OF PARTICLE BOARD: A MULTI-FACTOR ANALYSIS INCLUDING EFFECTS OF MINERAL CONTAMINANTS

    Directory of Open Access Journals (Sweden)

    Boleslaw Porankiewicz

    2008-05-01

    Full Text Available This paper evaluates and discusses multifactor non-linear, statistical dependencies of drill side-edges recession VBK and drill diameter recession DW on the cutting path length LC, the content of hard mineral contaminants CMC, the size of contaminant particles SMC, and the Mohs hardness MH. Significant influence of the cutting path LC, the content CMC of hard mineral contaminants (HMC, and the size of contaminant particles SMC was found, whereas the Mohs hardness MH of the contamination particles was less important.

  3. Phased Array Ultrasonic Sound Field Mapping through Large-Bore Coarse Grained Cast Austenitic Stainless Steel (CASS) Components

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Coble, Jamie B.; Diaz, Aaron A.; Anderson, Michael T.

    2012-09-01

    A sound field beam mapping exercise was conducted to assist in understanding the effects of coarse-grained microstructures found in cast austenitic stainless steel (CASS) materials on acoustic longitudinal wave propagation. Ultrasonic laboratory measurements were made on three specimens representing four different grain structures. Phased array (PA) probes were fixed on each specimen surface and excited in the longitudinal mode at specific angles while a point receiver was scanned in a raster pattern over the end of the specimen, generating a transmitted sound field image. Three probes operating at nominal frequencies of 0.5, 0.8, and 1.0 MHz were used. A 6.4 mm (0.25-in.) thick slice was removed from the specimen end and beam mapping was repeated three times, yielding four full sets of beam images. Data were collected both with a constant part path for each configuration (probe, specimen and slice, angle, etc.) and with a variable part path (fixed position on the surface). The base specimens and slices were then polished and etched to reveal measureable grain microstructures that were compared to the sound field interactions and scattering effects seen in the collected data.

  4. Ultrasonic Phased Array Sound Field Mapping Through Large-Bore Coarse Grained Cast Austenitic Stainless Steel (CASS) Piping Materials

    Energy Technology Data Exchange (ETDEWEB)

    Cinson, Anthony D.; Crawford, Susan L.; Prowant, Matthew S.; Diaz, Aaron A.; Hathaway, John E.; Anderson, Michael T.

    2012-04-16

    A sound field beam mapping exercise was conducted to further understand the effects of coarse grained microstructures found in CASS materials on phased array ultrasonic wave propagation. Laboratory measurements were made on three CASS specimens with different microstructures; the specimens were polished and etched to reveal measurable grain sizes, shapes and orientations. Three longitudinal, phased array probes were fixed on a specimen's outside diameter with the sound field directed toward one end (face) of the pipe segment over a fixed range of angles. A point receiver was raster scanned over the surface of the specimen face generating a sound field image. A slice of CASS material was then removed from the specimen end and the beam mapping exercise repeated. The sound fields acquired were analyzed for spot size, coherency, and beam redirection. Analyses were conducted between the resulting sound fields and the microstructural characteristics of each specimen.

  5. CHARACTERIZATION OF DANSYLATED CYSTEINE, CYSTINE, GLUTATHIONE, AND GLUTATHIONE DISULFIDE BY NARROW BORE LIQUID CHROMATOGRAPHY - ELECTROSPRAY IONIZATION MASS SPECTROMETRY

    Science.gov (United States)

    A method using reversed phase high performance liquid chromtography/electrospray ionization-mass spectrometry (RP-LC/ESI-MS) has been developed to confirm the dientity of dansylated derivatives of cysteine (C) and glutathione (GSH), and their respective dimers, cystine (CSSC) and...

  6. CHARACTERIZATION OF DANSYLATED CYSTEINE, GLUTATHIONE DISULFIDE, CYSTEINE AND CYSTINE BY NARROW BORE LIQUID CHROMATOGRAPHY/ELECTROSPRAY IONIZATION MASS SPECTROMETRY

    Science.gov (United States)

    A method using reversed phase high performance liquid chromatography/electrospray ionization-mass spectrometric (RP-LC/ESI-MS) method has been developed to confirm the identity of dansylated derivatives of cysteine and glutathione, and their respective dimers. Cysteine, GSH, CSSC...

  7. Stable and efficient operation of a large-bore copper vapor laser with funnel-shaped, grooved copper electrodes

    Science.gov (United States)

    Sadighi-Bonabi, R.; Pasandideh, K.; Zand, M.; Nazari Mahroo, H.

    2017-03-01

    Using an appropriate design of electrodes and adjustment of the thyratron decoupling circuit as a high-repetition-rate and high-voltage switch, very stable operation of a copper vapor laser at high pressures was obtained. This was achieved by canceling the intense filamentation in the laser plasma at the higher pressures. The transverse grooves on the inner surface of the funnel-shaped copper electrodes permit operation of the laser up to 100 torr. This design reduces the cathode-fall voltage, and as a result reduces the thermal loading in the cathode-fall region. The optimum pressure was 80 torr. At this condition the output power was more than that observed with expensive molybdenum electrodes in a similar laser system.

  8. Designing and operating multi-lateral completions that enable re-entry and selective intervention into one bore

    Energy Technology Data Exchange (ETDEWEB)

    Hamer, D. [Sperry Sun Drilling Service, Aberdeen (United Kingdom)

    1998-09-01

    Multi-lateral wells with a degree of complexity beyond simple barefoot side-tracks have been in commercial use since 1992. Hailed as the next great enabling technology after horizontal wells, their efficacy has been widely acknowledged by the industry, but their commercial application has seen slow growth rates in all but a few geographical locations. Perhaps we have learned from the experience of horizontal wells, where initial euphoria was eventually tempered by the realisation that they were not always appropriate. Initial results from early horizontal wells suggested that the intuitive assumption that they would produce positive benefits (in terms of improved recovery, better drainage patterns, less coning, better cash flow and improved NPV) were valid, but not always. (orig.)

  9. MODELING AND ANALYSIS OF DYNAMICS IN BEARING SYSTEM OF DRILLING, MILLING AND BORING MACHINE WITH MONO-COLUMN

    Directory of Open Access Journals (Sweden)

    Yu. V. Vasilevich

    2015-01-01

    Full Text Available  FEM-analysis of dynamics in the bearing system of a heavy-duty machine tool has been carried out in the paper. This is a prospective variant for a large-size multi-purpose machine tool with a horizontal sliding ram. A saddle and a ram are moving vertically along a subtle mono-column. A rigid double-column is used in the existing analog machine tool. A static, modal and harmonic analysis of the bearing system with the mono-column has been made in the paper. It has been done with the help of FEM-simulation prior to fabrication of a prototype sample. Previously conducted calculations for the analog machine tool have shown good compatibility of FEM-calculation with experiments.Six common machine tool resonances have been revealed for the bearing system. Their oscillating cutting forces are actively exciting three-four resonance modes. Ranges of a flexure-torsion resonance (20–40 Hz and nose-diving resonances (70–90 Hz have been determined in the paper. The paper shows that the range of multi-wave resonances starts significantly higher from 140 Hz. These resonances are interconnected with bending oscillations of the ram and bucklings of the column walls which are matched with the oscillations. The paper demonstrates stability in resonance pattern. The torsional resonance of the column on the frequency of nearly 40 Hz is considered as the more dangerous one. Spindle rigidity goes down up to 3.8 Н/μm. It is possible to observe self-stabilization of the torsional resonance. Frequency of the torsional oscillations is practically unchangeable when there is a lifting or lowering down of the saddle and the ram. It is related to the migration of dynamical axis of torsion.Frequency-response characteristics of the bearing system have been constructed for various saddle positions on the column. Three frequency intervals that make it possible to carry out machining operation have been determined in the paper. The first interval is a static one. The machine tool with a mono-column comes short of the analog machine tool in this interval. The main reason of it is low static rigidity of the subtle column. The second interval is narrow and it is located between flexure-torsion and nose-diving resonances. The third interval is considered as the most efficient one. The interval contains a section of inter-range pause between general machine tool and multi-wave resonances. In this case it is possible to observe a significant increase of the dynamic rigidity on the spindle that compensates the column subtility. High potential of the dynamic rigidity has been revealed in the direction of the ram axis (>2000 Н/μm. The paper shows liability of the machine tool to displacement crossings during oscillations. Peculiar features of this effect have been discussed in the paper. The diagram with a mono-column is recommended for practical application. The main condition is a transition to high-speed drive within the framework of concept on high-speed machining. It is necessary to ensure rigidity of the axial feed drive system.

  10. Quantitative discrimination between oil and water in drilled bore cores via fast-neutron resonance transmission radiography

    CERN Document Server

    Vartsky, D; Dangendorf, V; Israelashvili, I; Mor, I; Bar, D; Tittelmeier, K; Weierganz, M; Breskin, A

    2016-01-01

    A novel method based on Fast Neutron Resonance Transmission Radiography is proposed for non-destructive, quantitative determination of the weight percentages of oil and water in cores taken from subterranean or underwater geological formations. The ability of the method to distinguish water from oil stems from the unambiguously-specific energy dependence of the neutron cross-sections for the principal elemental constituents. Monte-Carlo simulations and initial results of experimental investigations indicate that the technique may provide a rapid, accurate and non-destructive method for quantitative evaluation of core fluids in thick intact cores, including those of tight shales for which the use of conventional core analytical approaches appears to be questionable.

  11. The perfect boring situation-Addressing the experience of monotony during crewed deep space missions through habitability design

    Science.gov (United States)

    Peldszus, Regina; Dalke, Hilary; Pretlove, Stephen; Welch, Chris

    2014-01-01

    In contemporary orbital missions, workloads are so high and varied that crew may rarely experience stretches of monotony. However, in historical long duration missions, occurrences of monotony were, indeed, reported anecdotally by crew. Of the effective countermeasures that appear to be at hand, many rely on visual or logistical proximity to the Earth, and are not feasible in the remote context of an extended deep space mission scenario. There, particularly in- and outbound cruising stages would be characterised by longer, comparably uneventful periods of low workload, coupled with confinement and unchanging vehicle surroundings. While the challenge of monotony has been pointed out as an exploration-related research area, it has received less explicit attention from a habitation design perspective than other human behaviour and performance issues. The paper addresses this gap through a literature review of the theory and application of design-based mitigation strategies. It outlines models of emergence of monotony, situates the phenomenon in a remote mission context as a problem of sensory, social and spatio-temporal isolation, and discusses proposed countermeasures related to habitability. The scope of the literature is extended to primary sources in the form of a qualitative review of six onboard diaries from orbital and simulator missions, highlighting a range of habitat-related design themes. These are translated into the autonomous deep space setting with the overall rationale of integrating affordances into onboard habitation systems and placing emphasis on reinforcing positive situational characteristics.

  12. Progress and gaps in understanding mechanisms of ash tree resistance to emerald ash borer, a model for wood-boring insects that kill angiosperms.

    Science.gov (United States)

    Villari, Caterina; Herms, Daniel A; Whitehill, Justin G A; Cipollini, Don; Bonello, Pierluigi

    2016-01-01

    We review the literature on host resistance of ash to emerald ash borer (EAB, Agrilus planipennis), an invasive species that causes widespread mortality of ash. Manchurian ash (Fraxinus mandshurica), which coevolved with EAB, is more resistant than evolutionarily naïve North American and European congeners. Manchurian ash was less preferred for adult feeding and oviposition than susceptible hosts, more resistant to larval feeding, had higher constitutive concentrations of bark lignans, coumarins, proline, tyramine and defensive proteins, and was characterized by faster oxidation of phenolics. Consistent with EAB being a secondary colonizer of coevolved hosts, drought stress decreased the resistance of Manchurian ash, but had no effect on constitutive bark phenolics, suggesting that they do not contribute to increased susceptibility in response to drought stress. The induced resistance of North American species to EAB in response to the exogenous application of methyl jasmonate was associated with increased bark concentrations of verbascoside, lignin and/or trypsin inhibitors, which decreased larval survival and/or growth in bioassays. This finding suggests that these inherently susceptible species possess latent defenses that are not induced naturally by larval colonization, perhaps because they fail to recognize larval cues or respond quickly enough. Finally, we propose future research directions that would address some critical knowledge gaps.

  13. Proof-of-feasibility of using well bore deformation as a diagnostic tool to improve CO2 sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Murdoch, Larry [Clemson Univ., SC (United States); Moysey, Stephen [Clemson Univ., SC (United States); Germanovich, Leonid [Georgia Inst. of Technology, Atlanta, GA (United States); Hughes, Baker [Clemson Univ., SC (United States)

    2016-01-13

    Injecting CO2 raises pore pressure and this causes subsurface formations to deform. The pattern and amount of deformation will reflect the distribution of pressure and formation properties in the subsurface, two quantities of interest during CO2 storage. The hypothesis underlying this research is that the small deformation accompanying CO2 storage can be measured and interpreted to improve the storage process.

  14. Research on microwave processing to log with stem-boring insects%微波杀灭原木蛀干害虫的技术研究

    Institute of Scientific and Technical Information of China (English)

    高冬平; 樊培峰; 巨云为; 刘灏; 朱萍; 孙波

    2011-01-01

    Through the different temperatures of microwave treatment on the infected wood of Bursaphelenchus xylophilus,the survival of Monochamus alternatus larvae and the pine wood nematode as well as the wood properties (elastic modulus and static bending strength) were studied. The results showed that when the temperature of microwave treatment was reached to 50℃ for 5 minutes, the larvae of M. alternatus were completely killed in the diseased wood. The temperature of the microwave treatment was reached to 55℃ for 5 minutes, the pine wood nematode was all dead. The temperature of microwave treatment was around 60℃, the crack, elastic modulus and static bending strength the diseased wood were not significantly different from the control and could be used normally. Comprehensively, the microwave treatment of 55℃ was an effective way to treat the woods infected with B. xylophilus.%通过不同的微波温度处理松材线虫病死木原木,观察了微波对松材线虫疫木中松墨天牛幼虫及松材线虫存活的影响,同时初步研究了微波处理后原木在材性上的变化情况.结果表明,当微波处理温度达到50℃时,保持5 min,可完全杀灭病木中的松墨天牛幼虫;当微波处理温度达到55℃时,保持5 min,松材线虫完全死亡;温度在60℃左右时,对木材的开裂、抗弯弹性、抗弯强度等材性影响不显著,经微波处理的疫木可正常利用.因此,55℃的微波处理可作为松材线虫疫木除害的有效方法.

  15. Morphological and genetic diversity of the wood-boring Xylophaga (Mollusca, Bivalvia: new species and records from deep-sea Iberian canyons.

    Directory of Open Access Journals (Sweden)

    Chiara Romano

    Full Text Available Deep-sea bivalves of the Xylophagaidae, a poorly known group, are obligate wood-borers. Deployment of wood in three submarine canyons off the Iberian coast, the Blanes and La Fonera Canyons (Mediterranean Sea and the Avilés Canyon (Cantabric Sea, Bay of Biscay, lead to the discovery of four xylophagaid species in our samples. Xylophaga dorsalis (the dominant species, X. atlantica, X. cf. anselli and the new species X. brava, were identified on the basis of morphological data, and supported by a phylogenetic reconstruction based on the nuclear genes 18S rDNA and 28S rDNA and including several genus of Xylophagaidae. Genetic divergence between species of Xylophaga varied between genes, ranging from 0.5 to 4.0% for the 18SrDNA and from 4.1 to 16.6% for the 28SrDNA. Xylophaga brava sp. nov. appeared to be restricted to the Mediterranean and morphologically resembled the closely related X. cf. anselli from the Cantabrian Sea. However, they clearly diverged in two well-supported clades. Low levels of intraspecific variability and higher interspecific divergence between species also supported the existence of these two different species. Morphologically they differ in the number of cirri at the siphon openings, in the shape of the posterior shell and in the size of prodissoconch II. The new species is characterized by having weak, poorly mineralized mesoplax and siphons united throughout, covered by a periostracal, non-calcified tube; distinct proximal and distal siphons, the former translucent and soft, the latter muscular, with concentric rings. Xylophaga atlantica, previously known only from the western Atlantic, is reported for the first time in the Mediterranean Sea. Whether its presence in the Mediterranean indicates its natural distribution or reflects its recent introduction is unknown. Although xylophagaids have been previously reported to recruit heavily to wood deposited on the seabed, these four species colonized wood suspended 30 m above the seafloor.

  16. 致密储集层近井区堵塞带的产能方程%IPR of tight formation with jam near well bore

    Institute of Scientific and Technical Information of China (English)

    何顺利; 郑祥克

    2003-01-01

    目前对致密储集层的启动压力研究较多,但存在某些争议.基于Wiggins等建立解析IPR曲线的思想,推导出致密储集层近井区存在堵塞带时的产能方程,并根据该产能方程对影响流入动态的主要因素进行分析.结果表明,启动压力梯度的作用非常明显,堵塞半径与启动压力呈线性关系,地层压力越大产量的衰减幅度越小,表皮系数对无因次流入动态没有影响.用该理论方程与分析方法分析某低渗透油田2口井的生产动态,解释结果更符合生产实际.图5参13

  17. A conduction-cooled, 680-mm-long warm bore, 3-T Nb3Sn solenoid for a Cerenkov free electron laser

    NARCIS (Netherlands)

    Wessel, W.A.J.; Ouden, den A.; Krooshoop, H.J.G.; Kate, ten H.H.J.; Wieland, J.; Slot, van der P.J.M.

    1999-01-01

    A compact, cryocooler cooled Nb3Sn superconducting magnet system for a Cerenkov free electron laser has been designed, fabricated and tested. The magnet is positioned directly behind the electron gun of the laser system. The solenoidal field compresses and guides a tube-shaped 100 A, 500 kV electron

  18. A conduction-cooled, 680-mm-long warm bore, 3-T Nb3Sn solenoid for a Cerenkov free electron laser

    OpenAIRE

    Wessel, W. A. J.; Ouden, den, J.; Krooshoop, H. J. G.; Kate, ten, H.H.J.; Wieland, J.; Slot, van der, J.

    1999-01-01

    A compact, cryocooler cooled Nb3Sn superconducting magnet system for a Cerenkov free electron laser has been designed, fabricated and tested. The magnet is positioned directly behind the electron gun of the laser system. The solenoidal field compresses and guides a tube-shaped 100 A, 500 kV electron beam. A two-stage GM cryocooler, equipped with a first generation ErNi5 regenerator, cools the epoxy impregnated solenoid down to the operating temperature of about 7.5 K. This leaves a conservati...

  19. Optimisation de l'utilisation du gadolinium comme poison consommable dans le combustible nucléaire : Vers un REP sans bore

    OpenAIRE

    2013-01-01

    Reactivity excess in Nuclear Power Plants is controlled by reactor's active systems: boric acid dilution and control rods. Alternatively, negative reactivity insertion can be made in a passive way using burnable poisons, i.e. neutron absorbers, this is the case of gadolinium (Gd). In the industrial framework of U²³⁵ enrichment increase and boric acid restraint, the goal of this thesis is to optimize the distribution of gadolinium in UO₂ ceramics to obtain a high-performance provision of negat...

  20. 上海中心大厦钻孔灌注桩施工技术%CONSTRUCTION TECHNOLOGY OF BORED PILE IN SHANGHAI TOWER

    Institute of Scientific and Technical Information of China (English)

    蒋华福

    2010-01-01

    结合位于陆家嘴金融贸易核心区、将成为上海和全国新标志的"中国第一高楼"上海中心大厦超大超深钻孔灌注桩工程,剖析了其垂直度要求高、成孔难度大、桩端注浆控制难等施工技术特点和难点.针对该工程钻孔灌注桩的钻机就位和开孔、泥浆性能、钻进成孔、第一次清孔、钢筋笼制作、钢筋笼的安装与沉放、水下混凝土浇筑、压密注浆等主要工序阐述了其施工技术控制要点.

  1. Dynamic Contrast-Enhanced MRI Parameters as Biomarkers in Assessing Head and Neck Lesions After Chemoradiotherapy Using a Wide-Bore 3 Tesla Scanner.

    Science.gov (United States)

    Lerant, Gergely; Sarkozy, Peter; Takacsi-Nagy, Zoltan; Polony, Gabor; Tamas, Laszlo; Toth, Erika; Boer, Andras; Javor, Laszlo; Godeny, Maria

    2015-09-01

    Pilot studies have shown promising results in characterizing head and neck tumors (HNT) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), differentiating between malignant and benign lesions and evaluating changes in response to chemoradiotherapy (CRT). Our aim was to find DCE-MRI parameters, biomarkers in evaluating the post-CRT status. Two hundred and five patients with head and neck lesions were examined with DCE-MRI sequences. The time intensity curves (TIC) were extracted and processed to acquire time-to-peak (TTP), relative maximum enhancement (RME), relative wash-out (RWO), and two new parameters attack and decay. These parameters were analyzed using univariate tests in SPSS (Statistical Package for the Social Sciences, version 17, SPSS Inc. Chicago, USA) to identify parameters that could be used to infer tumor malignancy and post-CRT changes. Multiple parameters of curve characteristics were significantly different between malignant tumors after CRT (MACRT) and changes caused by CRT. The best-performing biomarkers were the attack and the decay. We also found multiple significant (p < 0.05) parameters for both the benign and malignant status as well as pre- and post-CRT status. Our large cohort of data supports the increasing role of DCE-MRI in HNT differentiation, particularly for the assessment of post-CRT status along with accurate morphological imaging.

  2. Is IPE just 'boring',1 or committed to problematic meta-theoretic|al assumptions? A critical engagement with the politics of method

    Directory of Open Access Journals (Sweden)

    Heloise Weber

    2015-12-01

    Full Text Available Abstract In my contribution to this forum on IPE, my aim is to add further to the critical interventions in the debate ignited by Benjamin Cohen. The call to discuss the state of IPE has been timely, though not only because (some IPE journals have indeed become uninteresting; much more is at stake. Intellectual debate in the field has now not only narrowed, but has also shifted away from engaging the underlying premises of (global development, inequalities, and relations of domination. As such, the mainstream framing of IPE is arguably also implicated in a project of 'gate-keeping'. This is not to say that the intellectual richness and creativity that Cohen has called for in the study of IPE does not exist; such work is pursued by scholars of IR, more broadly conceived, and not just by those in other disciplines. Such richer scholarship has for instance, been advanced by historical sociologists, postcolonial theorists, and critical scholars of global development/global political economy including many working from feminist political-economic perspectives. The absence of an engagement with such perspectives in the mainstream of IPE can perhaps be explained to some extent by reference to ideological dispositions and attempts to maintain a hold on the disciplinary core along epistemological and methodological premises committed to ostensibly power-free and value-free analysis. The consequences are felt, as Cohen notes, also in the context of training and preparing future generations of IPE scholars, where current practices tend to reproduce students unable to 'ask and respond to the big questions', and who have instead come to be satisfied with applying 'accepted' methods. Critical scholars, on the other hand, have continuously pushed beyond the analytical and theoretical boundaries, engaging for example, with questions of power, domination and resistance, and more often than not such analyses are grounded in empirical research. In this contribution, I aim to demonstrate, through a critical reconstructive sketch, how mainstream IPE falls short, and what the value is of alternative, relationally conceived, analytical approaches.

  3. Profiles of ion beams and plasma parameters on a multi-frequencies microwaves large bore electron cyclotron resonance ion source with permanent magnets.

    Science.gov (United States)

    Kato, Yushi; Sakamoto, Naoki; Kiriyama, Ryutaro; Takenaka, Tomoya; Kurisu, Yosuke; Nozaki, Dai; Sato, Fuminobu; Iida, Toshiyuki

    2012-02-01

    In order to contribute to various applications of plasma and beams based on an electron cyclotron resonance, a new concept on magnetic field with all magnets on plasma production and confinement has been proposed with enhanced efficiency for broad and dense ion beam. The magnetic field configuration consists of a pair of comb-shaped magnet surrounding plasma chamber cylindrically. Resonance zones corresponding for 2.45 GHz and 11-13 GHz frequencies are positioned at spatially different positions. We launch simultaneously multiplex frequencies microwaves operated individually, try to control profiles of the plasma parameters and the extracted ion beams, and to measure them in detail.

  4. 钻孔灌注桩沉渣厚度检测方法研究%Detection method for bottom sediment thickness of bored piles

    Institute of Scientific and Technical Information of China (English)

    王川婴; 韩增强; 王玉山

    2013-01-01

    通过理论分析和测试试验,对钻孔灌注桩桩底沉渣厚度的检测方法进行了研究,并开发了贯入式沉渣厚度检测系统.该系统使用便携式的ARM机替代计算机进行数据的采集和显示,并基于eMbedded C++开发了数据采集与分析软件,通过寻找沉渣与天然地层的分界面位置来确定沉渣厚度.最后通过试验对该系统的测试精度和对测试环境的要求进行了研究.结果显示,该方法的测量误差在0.01~0.09 cm之间,并且受不同测试环境的影响较小,能够较好地完成桩底沉渣厚度的检测.

  5. CONSTRUCTION TECHNOLOGY OF ROTARY DRILLING HOLE DRY IN BORED FILLING PILE%钻孔灌注桩旋挖干取土成孔施工技术

    Institute of Scientific and Technical Information of China (English)

    王玮

    2012-01-01

    According to the different strata and ground water level,construction of rotary drilling hole may using process with drilling pile dry and mud. Drilling pile dry without mud, hole wall do not produce sludge, thickness of waste in hole bottom is small,conducive to play the bearing capacity of pile. Meanwhile,high construction efficiency, mud - free emission,pollution of small,especially suitable for construction of urban construction foundation.%根据不同的地层及地下水位情况,旋挖钻成孔灌注桩可采用干取土成孔和泥浆护壁成孔工艺。干取土成孔工艺不需泥浆护壁,孔壁不产生泥皮,孔底渣土厚度小,利于桩基承载力的发挥。同时,施丁效率高,无泥浆排放,对环境污染小,尤其适合于城市建设基础的施工。

  6. On some Indo-Pacific boring endolithic Bivalvia species introduced into the Mediterranean Sea with their host – spread of Sphenia rueppelli A. Adams, 1850

    Directory of Open Access Journals (Sweden)

    A. ZENETOS

    2012-12-01

    Full Text Available The study of the endolithic molluscs found on/in living alien Spondylusshells collected in the Gulf of Iskenderun (Turkey brought to light three more alien bivalvia species namely Petricola hemprichi, Gastrochaena cymbium and Sphenia rueppelli. The presence of Sphenia rueppellideserves attention as it constitutes the first record of this species as living in the Mediterranean Sea. The definitive establishment and spreading of these bivalves in the basin seems to be also attested by careful analysis of specimens sampled in other southern Turkish localities and previously retained in local private collections. The present records raise some questions on the vector of arrival of the species in the Mediterranean Sea that could be strictly connected with their hosts.

  7. Meet the New You: In Teen Second Life, Librarians Can Leap Tall Buildings in a Single Bound and Save Kids from Boring Assignments--All before Lunch

    Science.gov (United States)

    Czarnecki, Kelly; Gullett, Matt

    2007-01-01

    This article presents and discusses a 3-D online environment known as Teen Second Life. TSL is a virtual environment geared just for youth, ages 13-17. Its social appeal is huge, especially for teens who are developmentally inclined to seek out the company of their peers. In TSL one can meet friends or make new ones, hang out, listen to music and…

  8. Single-Cylinder Engine Tests of Porous Chrome-Plated Cylinder Barrels with Special Bore Coatings for Radial Air-Cooled Engines

    Science.gov (United States)

    1946-01-01

    sulphamate solution at room temperature having a hydrogen-ion concentration of 1.5. The cylinder was plated for 2 minutes with a current density of 40...for any metal combination (reference 3), engine friction may be reduced somewhat by the use of a silver overplate as a bearing material on the...Cooled Engines. NACA ARR No. E5L18, 1945. 3. Hoyt, Samuel L.: Metals and Alloys Data Book. Reinhold Pub. Corp., 1943, p. 281. 4. Downing, B. F

  9. Temporal and spectral features of sounds of wood-boring beetle larvae: identifiable patterns of activity enable improved discrimination from background noise

    Science.gov (United States)

    Rhynchophorus weevil larvae produce economically important damage to ornamental and date palm crops that could be mitigated significantly by early detection and treatment. Acoustic technology has potential to enable early detection, but often it is difficult to distinguish insect sounds from backgr...

  10. 水下钻孔灌注桩施工技术与质量控制%Construction Technology and Quality Control of Underwater Bored Pile

    Institute of Scientific and Technical Information of China (English)

    范振鹏; 殷志坚; 汤旭明

    2006-01-01

    水下钻孔灌注桩的成桩质量不易控制,是施工界的一大难题.通过工程实例的施工经验,介绍了水下钻孔灌注桩施工工艺及质量控制要点,并提出了相应建议.检测结果表明,控制措施切实有效.

  11. Study of boron carbide evolution under neutron irradiation; Contribution a l'etude de l'evolution du carbure de bore sous irradiation neutronique

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, D. [CEA/Saclay, Dept. de Mecanique et de Technologie (DMT), 91 - Gif-sur-Yvette (France)]|[Universite Blaise Pascal, Clermont-Ferrand II, (CNRS), 63 - Aubiere (France)

    1999-07-01

    Owing to its high neutron efficiency, boron carbide (B{sub 4}C) is used as a neutron absorber in control rods of nuclear plants. Its behaviour under irradiation has been extensively studied for many years. It now seems clear that brittleness of the material induced by the {sup 10}B(n,{alpha}){sup 7}Li capture reaction is due to penny shaped helium bubbles associated to a high strain field around them. However, no model explains the behaviour of the material under neutron irradiation. In order to build such a model, this work uses different techniques: nuclear microprobe X-ray diffraction profile analysis and Raman and Nuclear Magnetic Resonance Spectroscopy to present an evolution model of B{sub 4}C under neutron irradiation. The use of nuclear reactions produced by a nuclear microprobe such as the {sup 7}Li(p,p'{gamma}){sup 7}Li reaction, allows to measure lithium profile in B{sub 4}C pellets irradiated either in Pressurised Water Reactors or in Fast Breeder Reactors. Examining such profiles enables us to describe the migration of lithium atoms out of B{sub 4}C materials under neutron irradiation. The analysis of X-ray diffraction profiles of irradiated B{sub 4}C samples allows us to quantify the concentrations of helium bubbles as well as the strain fields around such bubbles.Furthermore Raman spectroscopy studies of different B{sub 4}C samples lead us to propose that under neutron irradiation. the CBC linear chain disappears. Such a vanishing of this CBC chain. validated by NMR analysis, may explain the penny shaped of helium bubbles inside irradiated B{sub 4}C. (author)

  12. The improvements of tongs for boring lute hole of rear-axle housing%后桥壳镗琵琶孔夹具的改进

    Institute of Scientific and Technical Information of China (English)

    曲力戈

    2005-01-01

    原汽车后桥壳镗琵琶孔夹具的两端顶尖只能对单一尺寸的后桥壳进行定位,现对原夹具顶尖进行改进设计,改为组合式顶尖,加工不同型号的后桥壳时,可随时更换与之对应的顶尖,简单、灵活、方便、适用范围广.

  13. Construction Method and Technical Measurement of Drilling (Wash) Bore Concrete Piles%钻(冲)孔混凝土灌注桩施工方法与措施

    Institute of Scientific and Technical Information of China (English)

    吴运华

    2005-01-01

    某快速路工程有若干座桥梁,采用钻(冲)孔灌注桩基础,共112根,桩径φ1.0 m、φ1.5 m及φ1.8 m三种,桩长4.4~51 m,由于地质条件变化大,部分地层中有断层夹泥与溶洞等不良地质,主桥桩基位于深约8 m的水中,具有一定的施工难度.

  14. A Hybrid Monte Carlo Method Based Artificial Neural Networks Approach for Rock Boundaries Identification: A Case Study from the KTB Bore Hole

    Science.gov (United States)

    Maiti, Saumen; Tiwari, R. K.

    2009-11-01

    Identification of rock boundaries and structural features from well log response is a fundamental problem in geological field studies. However, in a complex geologic situation, such as in the presence of crystalline rocks where metamorphisms lead to facies changes, it is not easy to discern accurate information from well log data using conventional artificial neural network (ANN) methods. Moreover inferences drawn by such methods are also found to be ambiguous because of the strong overlapping of well log signals, which are generally tainted with deceptive noise. Here, we have developed an alternative ANN approach based on Bayesian statistics using the concept of Hybrid Monte Carlo (HMC)/Markov Chain Monte Carlo (MCMC) inversion scheme for modeling the German Continental Deep Drilling Program (KTB) well log data. MCMC algorithm draws an independent and identically distributed (i.i.d) sample by Markov Chain simulation technique from posterior probability distribution using the principle of statistical mechanics in Hamiltonian dynamics. In this algorithm, each trajectory is updated by approximating the Hamiltonian differential equations through a leapfrog discrimination scheme. We examined the stability and efficiency of the HMC-based approach on “noisy” data assorted with different levels of colored noise. We also perform uncertainty analysis by estimating standard deviation (STD) error map of a posteriori covariance matrix at the network output of three types of lithofacies over the entire length of the litho section of KTB. Our analyses demonstrate that the HMC-based approach renders robust means for classification of complex lithofacies successions from the KTB borehole noisy signals, and hence may provide a useful guide for understanding the crustal inhomogeneity and structural discontinuity in many other tectonically critical and complex regions.

  15. Bored to Death: Community-Wide Effect of Predation on a Foundation Species in a Low-Disturbance Arctic Subtidal System.

    Directory of Open Access Journals (Sweden)

    Eugeniy Yakovis

    Full Text Available The strength of top-down control by consumers is predicted to decrease with latitude, but most data confirming this assumption come from latitudes <60°, while empirical studies of predation in sub-arctic and arctic marine habitats are few. A barnacle Balanus crenatus is a native foundation species in the shallow subtidal of the White Sea (65° N, hosting a diverse (250+ species assemblage of macrobenthic organisms. On mixed sediments live barnacles share primary substrates (shells and gravel with numerous empty barnacle tests, 7% of which had drill holes of an unidentified origin. We manipulated the densities of (i adult muricid whelks Boreotrophon clathratus (of previously unknown feeding habits, to check if they prey on barnacles, (ii other predators to reveal their effect on juvenile Boreotrophon, and (iii empty tests to assess the community-wide effect of predation on barnacles. The abundance of drilled empty tests in the field correlated with that of Boreotrophon. A year-long caging experiment clearly confirmed predation, showing the highest barnacle mortality and proportion of drilled tests in whelk enclosures, and the lowest--in predator exclosure treatments. Boreotrophon preferred the barnacles attached to conspecifics to those from primary substrates. Because of its scarcity Boreotrophon had a minor direct effect on barnacle abundance in the field. Yet, initially defaunated empty tests and live barnacles developed markedly different macrobenthic assemblages, suggesting a strong indirect effect of the predation. Juvenile Boreotrophon were 5-6 times less abundant in open and partial cages than in exclosures and enclosures, which indicates that the recruitment and, consequently, the abundance of Boreotrophon and its predation on Balanus are top-down controlled by apex predators. In contrast, in tropical and temperate intertidal the predation on barnacles is stronger and primarily limited by environmental stress and prey availability.

  16. 基于ADAMS的动力减振镗杆仿真分析%Simulation Analysis of Dynamical Vibration Absorption Boring Bar Based on ADANS

    Institute of Scientific and Technical Information of China (English)

    邵俊鹏; 秦柏

    2008-01-01

    建立了基于ADAMS的内置式动力减振镗杆动力学仿真模型,以减小刀刃径向跳动在整个频域内响应的最大值为目标对样机模型进行了优化分析,得出了减振系统的最优参数.仿真试验表明优化后系统的频域响应得到了改善.在此基础上分析了模型中的弹簧刚度系数、粘性阻尼系数、调谐块质量、减振腔尺寸以及调谐块质心位置对系统减振效果的影响,为减振系统进一步的优化设计提供了设计依据.

  17. 硬岩隧洞掘进机(TBM)刀具的管理%Management of cutter-heads of TBM for hard rock boring

    Institute of Scientific and Technical Information of China (English)

    张勇智

    2007-01-01

    文章对硬岩隧洞掘进机(TBM)刀具的管理内容进行了分析,使施工技术人员和生产管理人员能够清楚地认识到只有对刀具进行管理,那么在TBM施工中才能够降低生产成本,节约检修时间,提高掘进效率,从而为企业带来巨大的经济效益.

  18. Elaboration and characterisation of SiAlON-boron nitride refractory ceramic composites; Elaboration et caracterisation de composites ceramiques refractaires SiALON-Nitrure de bore

    Energy Technology Data Exchange (ETDEWEB)

    Doche, C.

    1996-05-07

    SiAlON-BN are materials able to replace carbon refractories used in steel-making shop, especially for low carbon steels elaboration. Two family of composites are studied: Si{sub 3}N{sub 4}-BN obtained by hot compression, and SiAlON-BN by natural sintering. In the first case, an organic precursor of BN which seems to activate the sintering process was also used. For all these materials, we studied elaboration processes, microstructures, mechanical properties, and thermal shocks, oxidation and corrosion resistances by liquid iron. BN presence lowers mechanical properties, but increases thermal shock and oxidation resistance at high temperature. From all the sintering add-on, Y{sub 2}O{sub 3}, Nd{sub 2}O{sub 3}, La{sub 2}O{sub 3}, CeO{sub 2}, neodymium and lanthanum oxides seems to give a light improvement of high temperature resistance. (A.B.)

  19. 深长钻孔掩护抽放技术的应用%Application of the deep and length-bore shield drainage technology

    Institute of Scientific and Technical Information of China (English)

    王一名

    2015-01-01

    岳城煤矿在掘进巷道进行深长钻孔掩护抽放技术探索,经过2年多的应用实践,取得了较好效果,掘进顺槽取得了单掘进尺480 m以上的应用成果,解决了高瓦斯矿井单掘效率低的问题,为高瓦斯矿井掘进巷道瓦斯治理积累了宝贵的经验.%Yuecheng coal mine explore the deep drilling shield drainage technology in heading, by practiced for more than two years, the technology achieved good effect, achieved the effect that the excavation footage is more than 480m per month, solved the low efficiency problem in high gas mine, accumulated valuable experience for the gas governance of high gas coal mine during excavating.

  20. Research and Discussion of Multifuctional Raise Boring Machine%多功能反井钻机的研究与探讨

    Institute of Scientific and Technical Information of China (English)

    曹年宝

    2010-01-01

    多功能反井钻机是在现有反井钻机基础七开发出来的,既可以向下钻扩孔又可以向上钻扩孔,借鉴了Atlas-Copoco公司Robbins类型反井钻机的设计经验,填补了国内反井钻机的一项空白,为国内反井钻机的发展和更广泛的应用提供了一种新的思路.

  1. Water Well Locations, Geodatabase of water well and test boring locations in Delaware, Published in 1970, 1:24000 (1in=2000ft) scale, Delaware Geological Survey.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Water Well Locations dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Hardcopy Maps information as of 1970. It is described as...

  2. Alpheus saxidomus new species, a rock boring snapping shrimp from the Pacific coast of, Costa Rica, with notes on Alpheus simus Guérin-Méneville, 1856

    NARCIS (Netherlands)

    Holthuis, L.B.

    1980-01-01

    Recently, Professor Dr. Rudolf Fischer, Institut für Geologie und Paläontologie, Philipps-Universität, Marburg, F. R. Germany, submitted for identification some material of an Alpheid shrimp, which was found to be responsible for a considerable erosion of part of a rocky shore on the Pacific coast o

  3. Cooper River Rediversion Project. Lake Moultrie and Santee River, South Carolina. Intake and Tailrace Canals. Appendix A. Boring Logs and Laboratory Test.

    Science.gov (United States)

    1976-06-01

    r ivdiversion Charleston District - CLAS’StrIAT.ON F COR bOX OR $tARKS ECOV SAMPLE fl.ls,,, . . . . / . ER) NC,*O .[ tU , _ Limestone, dark gray...OR REMARKS FL AICN DE PT, EEND L-t’ ECOv - SAAMPLE T),,~,,,~,. .dp,h .1 ELY NO ’IP.f d e f - g Blow/Ft I M-Siltv Fine and Med. Sand 16 I Ylow mc16.3% 79

  4. Mise en évidence d'un nouvel anion à huit atomes de bore dans Tl 4[B 8O 12(OH) 4]H 2O

    Science.gov (United States)

    Touboul, Marcel; Bois, Claudette; Amoussou, Denagnon

    1983-07-01

    The structure solution of an hydrated thallium diborate previously formulated Tl 2B 4O 7 · 2H 2O has led to the correct formula Tl 4[B 8O 12(OH) 4]H 2O. This compound is triclinic with a = 7.221(4)Å, b = 9.494(4)Å, c = 15.592(8)Å, α = 114°.86(4), β = 90°.25(7), γ = 99°.70(4), Z = 2, space group P overline1. Independent reflections numbering 1594 were used in the solution and refinement of the structure to R = 0.039 ( Rw = 0.042). The structure contains a new unit [B 8O 12(OH) 4] -, formed by four BO 4( T) tetrahedra and four BO 3(Δ) triangles. In the Christ and Clark classification for borates ( Phys. Chem. Mineral.2, 59 (1977)), the structural formula should be written [B 7O 10(OH) 3 · OBO(OH)] 4-. A fundamental building block with seven boron atoms is found for the first time; the correspondent fully hydrated polyanion is [B 7O 9(OH) 7] 4-; the shorthand notation is 7 : 3 Δ + 4 T. The units [B 7O 10(OH) 3 · OBO(OH)] 4- or 7 : (3 Δ + 4 T) + Δ are linked together to form an infinite chain. Tl + and H 2O are located between the chains.

  5. Pentaxial access platform for ultra-distal intracranial delivery of a large-bore hyperflexible DIC (distal intracranial catheter: A technical note

    Directory of Open Access Journals (Sweden)

    Li-Mei Lin

    2016-12-01

    Conclusion: Distal intracranial catheters can achieve ultra-distal intracranial positions safely with the pentaxial access platform. This technique is a near no step-off, atraumatic method of navigating a DIC in a stepwise fashion over de-escalating smaller diameter catheters via a microwire. Familiarity with catheter specifications including diameters and length is essential for the success of this system.

  6. Cross-polarization borehole radar system with a RF analog optical transmission link. Hikaridenso ni yoru chokko henpa bore hole radar keisoku system

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, T.; Sato, M.; Niitsuma, H. (Tohoku University, Sendai (Japan). Faculty of Engineering)

    1994-05-01

    The cross-polarization borehole radar system (BRS) was reported. The RF analogue optical transmission system (using the optical fiber cable) was introduced into the signal transmission between the sonde and the surface station to broaden the band and to heighten the S/N ratio. The sonde consisted of cable head (to transmit the trigger signal), receiving antenna, and transmitting antenna. The transmitting antenna was excited by the trigger signal from the surface to generate the pulse by the pulse generator. The signal received by the receiving antenna was sent to the oscilloscope on the surface. The field test of cross-polarization borehole system revealed that the effect of noise associated with the BRS employing the eccentric cable did not appear on the BRS. Examples of field test of the cross-polarization borehole measurement system employing the BRS were described. 4 refs., 8 figs., 1 tab.

  7. 78 FR 79390 - Foreign-Trade Zone (FTZ) 265-Conroe, Texas, Notification of Proposed Production Activity, Bauer...

    Science.gov (United States)

    2013-12-30

    ... Activity, Bauer Manufacturing Inc., (Pile Drivers, Boring Machinery, and Foundation Construction Equipment..., boring machinery, foundation construction equipment, foundation casings, related parts and sub-assemblies... construction equipment, foundation casings, and tools and accessories for pile drivers and boring...

  8. 应用Lingo非线性规划软件的钻孔灌注桩优化设计%The Optimal Design of Bored Pile Using Lingo Nonlinear Programming Software

    Institute of Scientific and Technical Information of China (English)

    郑怡; 常立峰

    2004-01-01

    优化设计在考虑结构安全性要求的同时,也考虑了经济性的要求,本文结合传统的钻孔灌注桩设计之不足,对钻孔灌注桩进行了优化设计,针对其中数学模型的非线性规划问题,应用了Lingo非线性规划软件进行编程求解,由此证明了Lingo非线性规划软件在解决工程非线性优化问题上是一个很成功的软件.

  9. 基于三维形貌重建的镗加工表面粗糙度检测%Boring Surface Roughness Detection Based on 3D Topography Reconstruction

    Institute of Scientific and Technical Information of China (English)

    郭便

    2011-01-01

    以计算机显微视觉为检测手段,采用明暗恢复形状方法重建加工表面微观形貌,进而检测加工表面粗糙度.根据微观金属表面反射特性,采用基于Torrance-Sparrow光照模型的明暗恢复形状算法,完成了镗加工表面图像三维形貌重构与表面粗糙度参数检测.%Computer micro- vision is taken as the detection means.The 3D topography and roughness parameters of the workpiece surface was obtained by 3D reconstruction of the gray images of the workpiece surface using shape from shading.The SFS algorithm based on Torrance -Sparrow illuminant model was applied according to reflective characteristics of the metal micro - surface, 3D topography reconstruction and roughness detection of the workpiece surface was completed.

  10. Analysis of Simulation of Tunnel Boring Machine Based on Digital Mockup%基于数字样机技术的全断面掘进机仿真分析

    Institute of Scientific and Technical Information of China (English)

    程军; 巩亚东; 彭立华

    2010-01-01

    介绍了数字样机技术.针对目前全断面掘进机的市场应用背景,讨论了它的工作原理并进行受力分析.以某EPB型土压平衡式全断面掘进机为例建立数字样机,并进行了工作过程的运动学仿真.运用CATIA的有限元分析功能,对掘进机中重要部件进行了结构分析和动态特性分析.

  11. Study of boron effect on FeAl alloys with an ordered B2 structure; Etude de l'effet du bore sur les alliages FeAl ordonnes de structure B2

    Energy Technology Data Exchange (ETDEWEB)

    Gay-Brun, A.S

    1998-06-01

    FeAl alloys with an ordered B2 structure have good corrosion resistance and mechanical properties at high temperature. Nevertheless, their use is limited by the intergranular embrittlement at ambient temperature. It has already been shown that a doping by low amounts of boron can solve the problem of intergranular embrittlement. The aim of this work is to better understand the boron effect on the FeAl alloys. It has been confirmed that the boron doping change the mode of rupture of the FeAl alloys with a B2 structure; their strain on breaking point is increased. The limit of solubility of boron in Fe-40Al has been estimated between 400 and 800 ppm at 500 degrees Celsius. Above this limit, Fe{sub 2}B precipitates. The intergranular segregation of boron has been observed by Auger electron spectroscopy for all the FeAl alloys. The intergranular amount of boron is low (below 12%). In the range of boron solubility, the intergranular concentration of boron increases with its voluminal amount. From this result, boron segregation has been described by different models of equilibrium segregation; thus has been shown that it exists a strong repulsion energy between the segregated boron atoms. On the other hand, no equilibrium segregation model can describe the independence to temperature of the boron segregation and its very fast kinetics: these two characteristics have certainly to be explained by a segregation mechanism under equilibrium. The existence of a segregation mechanism under equilibrium has been confirmed by the observation of the acceleration of the vacancies elimination kinetics by boron. The interaction between the boron atoms and the thermal vacancies which migrates to grain boundaries lead to the formation of complexes. The importance of the boron effect is not limited to its role to grain boundaries. Indeed, has been observed a strong decrease of the long order distance in the alloys doped with boron. The structure of the dislocations created by the vacancies elimination shows too that boron induces a modification of the mechanism of vacancies elimination. (O.M.)

  12. 大口径地下原水管线断裂失效的原因分析%Cause analysis of fracture failure of large-bore underground raw water pipeline

    Institute of Scientific and Technical Information of China (English)

    孙茂文

    2015-01-01

    通过对某原水管线断裂各种可能因素进行检测分析,排除了管线工艺操作造成管线断裂的因素。最终确定管段焊接质量缺陷及管线未消除热胀冷缩应力是断裂的主要原因,及时进行维修,同时提出了整改措施,避免故障进一步扩大。%Through the detection and Analysis on all possible factors of fracture of a raw water pipeline,factor of pipeline operation was eliminated from the cause for pipeline fracture. It was finally determined that the main causes were pipe welding quality had defects and pipeline was not eliminated the thermal expansion and contraction stress ,and timely maintenance was to be carried out. At the same time,the rectification measures were put forward to avoid further expansion of the fault.

  13. Multi-Mode Controlling of Boring-Milling Machine based on SFC Fuction%基于SFC功能的专用镗铣床的多模式控制

    Institute of Scientific and Technical Information of China (English)

    郑贤瀛

    2013-01-01

    在专用机床的PLC控制设计中,多数厂家采用梯形图设计,不同的设计人员对于相同的功能设计思路也不同,以至于其他人要理解起来比较困难.采用顺序功能的方法对专用镗床进行了PLC设计,并针对机床的多模式控制处理进行了重点描述,旨在阐明SFC编程方法的优势所在,即编程思路清晰,易于上手,不同的人员都比较容易理解其他人编写的程序,尤其适用于多模式控制的复杂应用.本案例经过实践检验,完全达到设计及使用要求,具有一定的实用价值.

  14. The design of automatic tool change system of boring and milling machining center based on PMAC%基于PMAC的镗铣加工中心自动换刀系统的设计

    Institute of Scientific and Technical Information of China (English)

    孙建业; 孙文娟; 王国勋

    2013-01-01

    设计了一种新型双刀库自动换刀系统,此系统充分利用了PMAC本身控制系统的优势,构建以IPC机为上位机、PMAC为下位机的双CPU换刀数控系统;系统采用计算记忆式选刀模式,通过建立虚拟刀库数据表控制刀库的就近选刀;直接在PEWIN32PRO中编写PLC换刀程序,运行加工程序时直接调用换刀子程序,换刀过程简捷方便.经试验台运行调试后证明,此换刀系统换刀时间短,运行稳定可靠,满足镗铣加工中心换刀要求.

  15. 基于超磁致伸缩材料的非网曲面形活塞销孔加工新型机构%Novel mechanism for boring non-cylinder piston pinhole based on giant magnetostrictive materials

    Institute of Scientific and Technical Information of China (English)

    翟鹏; 张承瑞; 王新亮; 秦磊; 秦有志

    2008-01-01

    To bear more loads for heavy truck pistons, the shape of heavy truck piston pinhole is often designed as non-cylinder form. Current methods cannot meet the needs for precision machining on non-cylinder piston pinhole (NCPPH). A novel mechanism based on giant magnetostrictive materials (GMM) is presented. New models are established for the servo mechanism, GMM, and magnetizing force of the control solenoid to characterize the relationship between the control current of the solenoid and the displacement of the giant magnetostrictive actuator (GMA). Experiments show that the novel mechanism can meet the needs to perform fine machining on NCPPH effectively.

  16. 优质泥浆在旋挖钻孔灌注桩护壁中的应用%Application of High Quality Mud in Wall Protection for Rotary Bored Pile Engineering

    Institute of Scientific and Technical Information of China (English)

    林礼进

    2013-01-01

    The causes of the hole collapse in rotary drilling are analyzed with a case of pile foundation project in Fujian. According to the formation characteristics, high quality mud configuration was adopted for wall protection with good practice effects.The paper introduces the preparation methods of the high quality mud and presents the application effects.%分析了福建石狮中竣商城桩基工程旋挖成孔钻孔塌孔的原因,根据地层特点配置了优质泥浆并用于钻孔护壁,取得了较好的实践效果。介绍了优质泥浆的配制方法及应用效果。

  17. TBM掘进工时利用率动态优化系统研究%Research on dynamic optimized system of increasing constantly the TBM boring operation rate

    Institute of Scientific and Technical Information of China (English)

    段晓晨; 张小平

    2000-01-01

    在深入分析国内外TBM 掘进工时利用统计资料和经验基础上,针对国家重点工程西康铁路秦岭隧道TBM掘进实际,从TBM人员组织、管理水平评价改善及工时利用优化决策等方面,深入论述了TBM掘进工时利用率动态优化系统建立和应用过程.

  18. A Brief Talk On Construction Quality Control Of Dry Pore-forming Concrete Bored Pile%浅谈干成孔砼灌注桩的施工质量控制

    Institute of Scientific and Technical Information of China (English)

    徐滨辉; 吕玉新

    2009-01-01

    桩基础作为建筑工程中常见基础且为强制验收项目之一,是建筑工程施工质量控制的重中之重.然而由于桩基础工程本身的隐蔽性,给施工质量控制带来一定的难度.笔者凭借多年以来对桩基础施工的分析,总结了一些桩基础施工控制的相关经验.

  19. Boring and excavation technologies for Opalinus clay in the rock laboratories at Mont Terri; Techniques de forages et d'excavations dans les argiles à Opalinus, laboratoire souterrain du Mont Terri

    Energy Technology Data Exchange (ETDEWEB)

    Bossart, P.; Nussbaum, Ch. [Swiss Federal Office of Topography swisstopo, Wabern (Switzerland); Burrus, F. [Groupe Grands Travaux GGT, Porrentruy (Switzerland)

    2012-07-01

    This comprehensive article discusses the work done since 1996 at the rock laboratories at Mont Terri in the Swiss Jura Mountains. The work being done by fifteen international partners on the characterisation of the Opalinus clay with regard to its geological, hydro-geological, geochemical and geotechnical characteristics is reported on. Various methods of drilling are described that are able to preserve any tectonic crevices in the rock. Drilling under special conditions, including the use of nitrogen and argon atmospheres to prevent bacterial contamination, is looked at, as are the methods used in tunnelling without having to use water.

  20. An Important Method of Online Renovation of Gun Barrel Bore Surface Defect%火炮身管内膛表面缺陷在线修复的一种重要方法

    Institute of Scientific and Technical Information of China (English)

    徐新乐; 陈福砦

    2009-01-01

    火炮身管内膛表面缺陷修复是提高火炮弹道学性能的一种重要技术手段.在线修复方法利用火炮射击时产生的高温高压环境气化或离化修复剂材料,在身管内膛表面形成一层耐磨和耐烧蚀的陶瓷涂层,能有效地修复内膛表面缺陷.试验证明,在线修复可以使火炮内膛表面变得光滑平整,膛径增大趋势大大减缓.该方法是一种简便易行的并适用于所有火炮身管内膛表面缺陷修复的在线修复方法.

  1. Logging as a means of characterising the water in rock formations in groundwater collection borings; Utilizacion de diagrafias para la caracterizacion del agua de la formaciones en sondeos de captacion de aguas subterranea

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Curiel, J.M.; Miguel, M.J.; Dominguez, S.; Caparrini, N

    1998-12-01

    We present an improvement of the S.P. application to obtain water conductivity and total of dissolved solids in the permeable layers passed through open hole, supposing said levels completely water saturated (under phreatic level). The optimization consists of a methodology for the treatment and interpretation of S.P. logs as well as the development of computer codes to execute the following processes. Laboratory measurements to acquire a set of key values in the interpretation processes (R{sub w}e/R{sub w} and TDS/R{sub w}). Conversion of the obtained data and selected charts, with continuous application range, to analytical curves for their automatic procedure. Algorithms development in order to carry out the automatic determination of base line and the elimination of its displacements. This system have been applied over a set of 27 logs performed by the author in the south area of the Duero basin (Spain) as an example of multi-layered detrital. We show the conductivity and TDS results in comparison with the water analysis obtained through pumping. (Author) 30 refs.

  2. 小口径三偏心硬密封蝶阀密封圈的加工%Machining Process of Sealing Parts of Metal Sealed Small-bore Tri-eccentric Butterfly Valve

    Institute of Scientific and Technical Information of China (English)

    秦启祥; 李双虎

    2012-01-01

    By the analysis of structure of the metal sealed tritri-eccenlric parteccentric butterfly valve, using the NC machining method combining with traditional craft, solved the machining problem of metal sealed tri-eccentric butterfly valve, ensured the machining accuracy and improved the production efficiency.%通过对三偏心硬密封蝶阀结构分析,利用数控加工手段结合传统工艺,解决了小口径三偏心硬密封蝶阀密封圈的加工,保证了加工精度,提高了生产效率.

  3. The effect of bore number and diameter of the removable tray on accuracy of alginate impression%孔数和孔径对可拆卸式托盘取模模型精度的影响

    Institute of Scientific and Technical Information of China (English)

    陈青娅; 陈新民; 王年斌

    2007-01-01

    目的:研究可拆卸式托盘的固位孔孔数及孔径对托盘取模精度的影响,为临床提供取模精度较好的托盘.方法:制作金属模型,用2号成品托盘,孔数44、孔径2.6 mm的可拆卸式托盘,孔数32和29、孔径分别为3.0 mm、3.5 mm及4.0mm的2号可拆卸式托盘各取模并灌制5个石膏模型.用体视显微镜测量模型各标志点的距离,对所得数据进行统计分析.结果:①相同孔数不同孔径的可拆卸式托盘,随着孔径的增大,制取的石膏模型也变大,各线段的长度变化有明显统计学意义(p<0.01).②相同孔径不同孔数的可拆卸式托盘,孔数多的托盘制取的石膏模型较大,变化有统计学意义(P<0.05).③可拆卸式托盘中精度较好组的精度优于传统托盘,差异有统计学意义(p<0.05).结论:按照适宜的孔数和孔径制成的可拆卸式托盘,精度优于其它托盘,可作为临床新型托盘应用.

  4. 桩径对双排式钻孔抗滑桩的影响研究%Study on Influence of Pile Diameter on Double-row Bored Anti-sliding Piles

    Institute of Scientific and Technical Information of China (English)

    温祥虎; 叶四桥; 毛晓光

    2014-01-01

    针对治理推力较大的滑坡工程中常用双排抗滑桩,运用有限元程序ABAQUS建立双排式钻孔抗滑桩的有限元三维分析模型,在其它条件不变的情况下,分别改变模型中桩径,进行单因素分析.结果表明:在确定的桩间距和排间距下,桩径的变化,对双排式钻孔抗滑桩的桩的位移、内力、前后排桩承担滑坡推力的比例等均有影响;对桩身位移的影响尤其明显.桩径取值应有一个合适的范围,建议双排式钻孔抗滑桩桩径不宜小于1 m,在施工条件可行的情况下,宜选择直径较大的钻孔抗滑桩;双排式钻孔抗滑桩具有施工安全、速度快、节省成本等优点,值得推广.

  5. 深孔钻镗床控制系统改造与切削参数监测研究%Study on Control System Transformation and Cutting Parameter Monitoring for Deep Hole Boring Machine

    Institute of Scientific and Technical Information of China (English)

    杨福合; 胡振华; 庞明超

    2015-01-01

    Combining with actual situation of production and processing, the original machine tool control system defects were an⁃alyzed. According to the needs of users, a high automatic control and detection scheme was presented. The system was mainly composed by PLC, touch screen, inverter, servo drives, and the stepless speed regulation of spindle and tool feed speed, feed depth arbitrary control could be realized, so flexibility of the machining process could be ensured to the maximum extent. At the same time, cutting pa⁃rameter monitoring function could be used to improve machining precision and efficiency, to ensure the machining quality, reduce waste product rate.%结合生产加工的实际情况,分析了原深孔加工机床控制系统存在的缺陷,并根据用户的需求提出了一种高自动化的控制与检测方案。系统主要由PLC、触摸屏、变频器、伺服驱动组成,可实现主轴的无级调速和刀具进给速度、进给深度的任意控制,最大程度上保证了加工工艺的灵活性。同时,切削参数监控功能在提高加工精度与效率的同时,保证了加工质量,降低了废品率。

  6. Study on temporal and spatial distribution model of ground settlement induced by metro tunnels construction with bored method%地铁暗挖施工引起的地表沉降时空分布模型研究

    Institute of Scientific and Technical Information of China (English)

    张波; 马雪梅; 任雪峰; 孙建勋

    2014-01-01

    Taking the ground settlements analysis caused by tunnel excavation construction in one Beijing subway as an example,this paper carried out regress analysis of ground settlements distribution based on Peck formula by a large number of measured data,and got Gaussian curves which can include the measured data to the maximal degree and the forecast range of ground settlements through modifying. The regress analysis of ground settlements with time changing based on Logistic function is also implemented and the distribution law of ground settlements with time and velocity distribution law with time are also obtained. The space-time predicting curves calculated by this method are closely associated with the construction method and tunnel soil condition,and the calculated parameters such as settlement trough width coefficient,ground loss rate,time parameter can establish the database,which could predict the space-time distribution of ground settlement well.%以北京一地铁区间隧道暗挖施工引起的地表沉降分析为例,研究地表沉降分布规律及其时程分布规律。在大量实测数据的基础上,基于Peck公式进行地表沉降分布的回归分析,并通过修正,得到最大程度包络实测数据的高斯曲线,从而得到地表沉降的范围;基于Logistic函数模型,进行地表沉降随时间变化的回归分析,得到地表沉降时程分布规律和沉降速度时程分布规律。通过该方法得到的地表沉降时空预测曲线与隧道的土层性质、施工方法等密切相关。计算得到的沉降槽宽度系数、地层损失率、时间参数等可为预测沉降的时空分布提供参考数据。

  7. 适用于浅海小口径复合软管的接头形式研究%Research for End Fitting of Small-bore Composite Flexible Pipes in Shallow Water

    Institute of Scientific and Technical Information of China (English)

    唐建华; 王琳; 曲杰

    2012-01-01

    Design a type of the flexible pipe end fitting, which can have enough strength and leak tightness under certain pressure and can release the accumulated gas in the armor layers, and this type of end fitting have successfully achieved the connection and protection request of the flexible pipes. A major advantage of using the flexible pipes is their ability to work under extreme dynamic conditions and their relatively seabed adaptability and chemical compatibility properties and installation convenience compared with rigid carbon steel pipes.%设计了一种适用于软管结构的接头形式,在一定压力作用下保证软管的强度和密封性,同时能够释放金属铠装层中累积的渗透气体,成功实现复合软管的连接和保护.因其在动力特性、地形适应性、抗腐蚀性、安装等多方面的优势,越来越多的油田开发考虑采用软管采代替钢管,具有很大的发展前景.

  8. Electromagnetic railgun in-bore velocity measurement with microwave Doppler radar%多普勒雷达测量电磁轨道炮内弹道速度

    Institute of Scientific and Technical Information of China (English)

    程诚; 宋盛义; 关永超; 何勇; 高贵山; 李业勋; 仇旭

    2014-01-01

    介绍了W波段多普勒雷达测量电磁轨道炮内弹道度速度的基本方法,并对口径30 mm×25mm的串联增强型电磁轨道炮内弹道速度进行了实际测量.初步研究表明:雷达接收的信号易受到脉冲放电过程的干扰;雷达信号的信噪比取决于电枢与轨道电接触状态,在电源充电电压较低、接触面无电弧生成时测得了完整的内弹道速度,并与丝网靶和磁探针测量结果吻合;在较高充电电压条件下,由于电弧电接触产生的干扰,测速结果不够理想.

  9. 3D打印技术在全井眼叶片加工中的应用%Application of 3D Printing Technology in Full Bore Blade Machining

    Institute of Scientific and Technical Information of China (English)

    代平之

    2014-01-01

    本文介绍了油田开发过程中生产测井的概况,全井眼仪器的工作原理,在分析老结构全井眼仪器叶轮叶片使用过程中遇到的问题的基础上,通过3D打印技术对叶片进行了重新设计加工,使全井眼仪器的可靠性得到了很大的提高,同时也为他人设计提供新的思路与借鉴。%This paper introduces the general situation of production logging in oilfield development and the working principle of full borehole instruments . By analyzing the problems of old impeller blade structure which appeared in the use of full borehole production logging , the blade was redesigned and made by the 3D printing technology . The improvement greatly improves the reliability of the borehole instrument , and also provides new ideas and reference for others on this kind of designing .

  10. 硬岩隧道掘进机常见机械故障分析及相应处理方法%Analysis of the breakdowns of TBMs in boring hard rocks and their corresponding countermeasures

    Institute of Scientific and Technical Information of China (English)

    张勇智

    2006-01-01

    文章对能够造成硬岩隧道掘进机(TBM)在掘进中调向失控、刀盘不能启动、刀盘突然停转以及护盾不能正常工作等多种机械故障的原因进行了分析,并提出了切实可行的解决方案,对日后同类型TBM的施工有参考作用.

  11. 某超高射速舰炮弹药筒膛内横断问题技术分析%Technical Analysis of Cartridge Breaking in Bore for Super-high Firing Rate Naval Gun

    Institute of Scientific and Technical Information of China (English)

    马献怀

    2015-01-01

    针对某超高射速舰炮及其弹道炮试验过程中出现的药筒膛内横断问题,通过现场勘测、理论分析和故障还原试验,确定了故障原因。根据故障机理,经技术攻关,提出了解决措施,经过后续多次射击试验验证,故障再未复现,证明了解决措施的可行有效。分析结果对解决速射火炮类似故障有重要的参考价值。%Aimed at the cartridge breaking problem occurred during the test of super-high firing rate naval gun and ballistic gun,the failure causes were determined by site investigation,theo-retical analysis and failure reproduction test.The solution was proposed based on the failure mechanism and technology research.The same failure hasn't occurred again during many firing test.The results show the solution is reasonable and feasible,which provides an important ref-erence value for solving similar failure of rapid-fire gun.

  12. A practice of the roadway construction by using vertical shaft's sinking of bore hole system%利用立井凿井系统进行平巷施工的实践

    Institute of Scientific and Technical Information of China (English)

    李子长; 孟维波

    2010-01-01

    结合煤矿平巷施工的特殊情况,采用立井凿井系统进行了平巷施工,介绍了具体施工方法,总结了该方法的使用范围和核心原理,并通过实践检验,收到了良好的施工效果.

  13. On comparative analysis of static loading tests and high strain dynamic testing of bored piles%钻孔灌注桩的静载试验和高应变动测对比分析

    Institute of Scientific and Technical Information of China (English)

    孟利吉

    2013-01-01

    以具体工程为例,选取不同区域的5根基桩分别进行静载试验和高应变动测,通过静动对比分析,结果显示:在基桩进行静动对比试验的基础上,采用高应变动测是满足工程要求的,具有可行性,值得推广.

  14. 大直径钻孔灌注桩的动静对比试验研究%The contrast study between the high strain dynamic testing and the static loading test of large diameter bored piles

    Institute of Scientific and Technical Information of China (English)

    王耀禧; 张旭辉

    2005-01-01

    对实际工程基桩进行动静对比试验,验证Q-S曲线呈缓变型特征大直径灌注桩不宜采用高应变法检测其竖向抗压承载力,即是对JGJ 106-2003建筑基桩检测技术规范相应条文说明的数据补充.

  15. 恢复系数对弹丸膛内运动参数的影响%The Influence of Restitution Coefficient on the Projectile Motion Parameters in Bore

    Institute of Scientific and Technical Information of China (English)

    岳永丰; 沈培辉

    2012-01-01

    弹丸膛内运动过程中,将其前定心部和膛壁碰撞的恢复系数看成定值,不能真实反映弹丸运动过程.实际上,恢复系数是随前定心部撞击膛壁的速度而变化的.通过对弹炮模型简化成的单球碰撞系统进行有限元仿真,得到恢复系数随前定心部径向速度变化的函数关系.将上述关系应用于弹丸膛内运动的数学模型,计算结果与测量结果基本一致,因此考虑恢复系数的变化具有一定的合理性.

  16. MIX PROPORTION OPTIMIZATION AND DURABILITY OF BORED PILE CONCRETE UNDER SALINE SOIL CONDITION%盐渍土环境下钻孔灌注桩混凝土配合比优选及耐久性

    Institute of Scientific and Technical Information of China (English)

    陈波; 张文潇; 白银; 刘雪娟; 宁逢伟

    2016-01-01

    为优选硫酸盐与氯盐共存的盐渍土环境下桩基混凝土配合比方案,以普通钻孔灌注桩混凝土、高抗硫水泥复合大掺量矿物掺合料混凝土、普硅水泥复合大掺量矿物掺合料的高性能混凝土及添加防腐剂的高性能混凝土等4种混凝土为研究对象,研究了4种混凝土的抗硫酸盐侵蚀能力和抗氯离子侵蚀能力.结果表明:普通钻孔灌注桩混凝土抗硫酸盐侵蚀能力较强,但其抗氯离子侵蚀能力难以满足耐久性要求;高抗硫水泥复合大掺量矿物掺合料混凝土抗硫酸盐侵蚀能力较强,但其抗氯离子侵蚀能力一般;普硅水泥复合大掺量矿物掺合料的高性能混凝土同时具有优异的抗硫酸盐侵蚀能力和抗氯离子侵蚀能力;在高性能中添加防腐剂,在一定程度上降低了混凝土的耐久性.高性能钻孔灌注桩混凝土是一种适合盐渍土环境的耐久性高、经济成本低廉的混凝土.

  17. Influence of Compressive Strength on Durability of Bored Pile Concrete in Saline Soil Region%混凝土强度对盐渍土地区钻孔灌注桩耐久性的影响

    Institute of Scientific and Technical Information of China (English)

    陈波; 张文潇; 白银; 宁逢伟

    2016-01-01

    为了确定盐渍土强腐蚀环境下桩基混凝土强度等级,采用硅酸盐水泥和高抗硫酸硅酸盐水泥制备了两组(C40和C50)混凝土进行试验,考察了不同强度等级混凝土抗硫酸盐和抗氯离子的侵蚀能力.结果表明,在浸烘循环试验制度下,C50与C40抗压强度耐蚀系数差异不大;在浸泡试验制度下,砂浆试件的膨胀系数随强度等级的升高而减小,而强度等级对砂浆的抗折强度抗蚀系数影响不大;混凝土抗氯离子侵蚀能力随强度的增高而增强.综合考虑混凝土技术经济性能和施工质量控制水平,对于硫酸盐和氯盐共存环境下的桩基混凝土,建议采用C40高性能混凝土.

  18. 中深孔光面爆破在台阶式快速掘进中的运用%Application of Deep Bore Smooth Blasting to the Quick Drivage of the Step Type

    Institute of Scientific and Technical Information of China (English)

    赵建华

    2007-01-01

    鄂庄煤矿207运输巷下山全长1300m,倾角8°~17°,平均13°,其穿层布置于七层煤的顶底板附近,上部自-300西翼回风大巷开门,下部与-530二采石门联系,主要担负整个采区的运煤及回风任务。运输机位于207采区中部,布置在二采区的二、四层煤下山保护煤柱下。巷道为直墙半圆拱形断面,净宽3.2m,净高3.2m,荒断面11.7m2,净断面10.4m2。采用钻眼爆破掘进,P-60B型扒装机扒装,喷锚网喷支护。

  19. 磁悬浮控制技术在非圆镗削加工中的应用%Application of Magnetic Levitation Technology to Non-circular Boring

    Institute of Scientific and Technical Information of China (English)

    王海峰; 胡德金

    2008-01-01

    为了实现非圆异形孔的镗削加工,借鉴了主动磁悬浮控制技术.针对径向异形孔的加工特点,对磁悬浮主轴进行了运动学分析,建立了描述其运动的综合机电方程,并在工作点上进行了线性化处理.为了实现磁悬浮主轴的径向微动控制,采用了增益调度自适应控制算法.以某型号活塞的销孔加工为例进行了镗削试验,结果表明,通过控制磁悬浮主轴的旋转轴心沿设定的轨迹移动,能够实现椭圆异形孔的加工,并且能够获得高的加工精度和表面粗糙度.

  20. Discussion on Tunnel Boring by Laser Beam%一种用于隧道断面脆性硬岩的激光破岩原理探讨

    Institute of Scientific and Technical Information of China (English)

    顿苗苗; 宋宏伟; 王春苗

    2011-01-01

    As a new rock spallation technology, the application of advanced high power laser to rock tunnel drilling has been significantly improved recently. The research advances of laser rock spallation technology at home and abroad are summarized. Based on our studies and laser beam characteristics, the authors propose a new rock breaking technology called "laser-water spray method" which can be used to large-scale hard rock tunnel drilling. It is solved that the scale problem between tiny laser beam point and large tunnel cross-section. The feasibility and effectiveness of the prposed method are proved further by numerical simulation.%激光作为一种新型破岩技术,在用于岩石隧道开挖技术的研究中已经取得了较大进展.本文在总结国内外激光破岩技术研究进展的基础之上,结合现有激光光束的特点,提出了适用于大断面脆性硬岩隧道的激光-喷水破岩方法,并通过数值模拟进一步分析了这种方法的破岩效果.该方法解决了激光光点小而隧道工程开挖断面大的矛盾,具有很强的实用性.

  1. Pleural controversy: optimal chest tube size for drainage.

    Science.gov (United States)

    Light, Richard W

    2011-02-01

    In recent years, a higher and higher percentage of patients with pleural effusions or pneumothorax are being treated with small-bore (10-14 F) chest tubes rather than large-bore (>20 F). However, there are very few randomized controlled studies comparing the efficacy and complication rates with the small- and large-bore catheters. Moreover, the randomized trials that are available have flaws in their design. The advantages of the small-bore catheters are that they are easier to insert and there is less pain with their insertion while they are in place. The placement of the small-bore catheters is probably more optimal when placement is done with ultrasound guidance. Small-bore chest tubes are recommended when pleurodesis is performed. The success of the small-bore indwelling tunnelled catheters that are left in place for weeks documents that the small-bore tubes do not commonly become obstructed with fibrin. Patients with complicated parapneumonic effusions are probably best managed with small-bore catheters even when the pleural fluid is purulent. Patients with haemothorax are best managed with large-bore catheters because of blood clots and the high volume of pleural fluid. Most patients with pneumothorax can be managed with aspiration or small-bore chest tubes. If these fail, a large-bore chest tube may be necessary. Patients on mechanical ventilation with barotrauma induced pneumothoraces are best managed with large-bore chest tubes.

  2. Variability in bacteria and virus-like particle abundances during purging of unconfined aquifers.

    Science.gov (United States)

    Roudnew, Ben; Lavery, Trish J; Seymour, Justin R; Jeffries, Thomas C; Mitchell, James G

    2014-01-01

    Standard methodologies for sampling the physicochemical conditions of groundwater recommend purging a bore for three bore volumes to avoid sampling the stagnant water within a bore and instead gain samples representative of the aquifer. However, there are currently no methodological standards addressing the amount of purging required to gain representative biological samples to assess groundwater bacterial and viral abundances. The objective of this study was to examine how bacterial and viral abundances change during the purging of bore volumes. Six bores infiltrating into unconfined aquifers were pumped for five or six bore volumes each and bacteria and virus-like particles (VLPs) were enumerated from each bore volume using flow cytometry. In examination of the individual bores trends in bacterial abundances were observed to increase, decrease, or remain constant with each purged bore volume. Furthermore, triplicates taken at each bore volume indicated substantial variations in VLP and bacterial abundances that are often larger than the differences between bore volumes. This indicates a high level of small scale heterogeneity in microbial community abundance in groundwater samples, and we suggest that this may be an intrinsic feature of bore biology. The heterogeneity observed may be driven by bottom up processes (variability in the distribution of organic and inorganic nutrients), top-down processes (grazing and viral lysis), physical heterogeneities in the bore, or technical artifacts associated with the purging process. We suggest that a more detailed understanding of the ecology underpinning this variability is required to adequately describe the microbiological characteristics of groundwater ecosystems.

  3. Uncertainty Analysis for DAM Projects.

    Science.gov (United States)

    1987-09-01

    Director of WES during the publication of this report. Dr. Robert W. Whalin was Technical Director. CONTENTS PREFACE , o...It 20 is 1 13 ft Bliows Per Foo Blows Per Fool Solows Por Fool Boring SS-53-66 Boring SS-52-66 Boring SS-51-66 Fiur 29c Reuto atr eonto xeiet 7-139

  4. Tunnel Face Stability & New CPT Applications

    NARCIS (Netherlands)

    Broere, W.

    2001-01-01

    Nearly all tunnels bored in soft soils have encountered problems with the stability of the tunnel face. In several cases these problems led to an extended stand-still of the boring process. A better understanding of the face stability, and of the soil conditions around the tunnel boring machine, can

  5. Design Construction and Optimisation of Big-Bore Gas Wells in a Giant Offshore Field%海上特大气田大井眼气井的井眼设计、井身结构及其优化

    Institute of Scientific and Technical Information of China (English)

    李斌; 严新新

    2008-01-01

    一种大井眼气井钻井和完井程序正广泛应用于卡塔尔海滨North大型气田的开发.与以前的φ177.8 mm井眼设计相比,大井眼的优势在于可以减少井口数量从而降低开发费用,可以提高井口流动压力从而推迟安装压缩机.大井眼设计已用于个别气田,并在很多井上得到应用.迄今已有多口这样的井钻井并完井,而且都是世界上最高产的气井.这也是将大规模气田开发的大井眼设计与装备设计和制造的特色工业发展相结合的第一批海上气井.对详细设计评价、设备性能试验、质量程序等方面进行了广泛的系统性研究,以满足复杂的井眼可靠性设计要求.这些井的特点是锥形管柱设计,即通常所说的"大井眼优化"(OBB).本文讨论了这些OBB井在设计与施工中的难题,介绍了最初的OBB井设计、North气田预期会遇到的钻井难题、设备的临界规格,以及在过去4年中通过优化所完成的设计修正.

  6. Deposition of thin layers of boron nitrides and hydrogenated microcrystalline silicon assisted by high current direct current arc plasma; Deposition assistee par un plasma a arc a haut courant continu de couches minces de Nitrure de Bore et de Silicium microcristallin hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Franz, D. [Ecole Polytechnique Federale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne (Switzerland)

    1999-09-01

    In the frame of this thesis, a high current direct current arc (HCDCA) used for the industrial deposition of diamond, has been adapted to study the deposition of two types of coatings: a) boron nitride, whose cubic phase is similar to diamond, for tribological applications, b) hydrogenated microcrystalline silicon, for applications in the semiconductor fields (flat panel displays, solar cells,...). For the deposition of these coatings, the substrates were placed in the diffusion region of the arc. The substrate heating is mainly due to atomic species recombining on its surface. The deposition temperature, varying from 300 to 900 {sup o}C according to the films deposited, is determined by the substrate position, the arc power and the injected gas fluxes, without the use of any external heating or cooling system. Measurements performed on the arc plasma show that the electronic temperature is around 2 eV (23'000 K) while the gas temperature is lower than 5500 K. Typical electronic densities are in the range of 10{sup 12}-10{sup 1'}3 cm{sup -3}. For the deposition of boron nitride films, different boron precursors were used and a wide parameter range was investigated. The extreme difficulty of synthesising cubic boron nitride films by chemical vapour deposition (CVD) did not allow to stabilize the cubic phase of boron nitride in HCDCA. Coatings resulted in hexagonal or amorphous boron nitride with a chemical composition close to stoichiometric. The presence of hydrogen leads to the deposition of rough and porous films. Negative biasing of the samples, for positive ion bombardment, is commonly used to stabilize the cubic phase. In HCDCA and in our biasing range, only a densification of the films could be observed. A boron nitride deposition plasma study by infrared absorption spectroscopy in a capacitive radio frequency reactor has demonstrated the usefulness of this diagnostic for the understanding of the various chemical reactions which occur in this kind of plasma. Diborane dissociation, the different reactions and new species created in the gas phase, such as aminoborane, containing boron-nitrogen bonds, reveals a rich chemistry in the plasma phase. A large amount of atomic hydrogen is necessary to deposit hydrogenated microcrystalline silicon coatings. The study of HCDCA regarding the deposition of diamond has shown that this arc efficiently dissociates molecular hydrogen by way of intermediate vibrationally excited states. This efficient dissociation has allowed the fast deposition (up to 0.6 microns per minute) of highly crystalline silicon films, even without any addition of molecular hydrogen, where the atomic hydrogen was created by the molecular dissociation of silane (SiH{sub 4}). The nature of the deposition precursors is highly dependent on the magnetic field used to confine the arc. At low field, the deposition of hydrogenated silicon radicals created in the plasma leads to columnar growth, whereas with an increase of the magnetic field, the film growth is probably dominated by the deposition of crystallites created in the plasma phase, whose size increases with the field. Moreover, a strong dependence of the film morphology on the deposition parameters has been observed, in particular, regarding the substrate temperature, the hydrogen dilution and the magnetic field. This new deposition technique of hydrogenated microcrystalline silicon is promising for industrial applications. (author)

  7. 大口径毛细管气相色谱柱测定茶叶中三氯杀螨醇的残留量%Determination of Dicofol Residue in Tea by Wide-Bore Capillar y Gas Chromatographic Column

    Institute of Scientific and Technical Information of China (English)

    朱梦栩; 王勇

    2000-01-01

    报道了用大口径毛细管气相色谱柱测定茶叶中三氯杀螨醇残留量的方法.用体积分数为20%的丙酮-正己烷提取茶样中的三氯杀螨醇,采用微量化前处理方法,经弗罗里硅土-酸性硅藻土混合柱净化后,与氢氧化钾溶液进行碱解,以大口径毛细管柱分离,艾氏剂为内标,电子捕获检测器(ECD)测定.经过对绿茶、红茶的添加回收试验,平均回收率为94%,变异系数小于7.49%,检测低限为0.5 μg/kg.

  8. 升降机的工作原理--以数控卧式镗铣床刀库机械手为例%A Investigation into the Working Principle of Elevator---Taking CNC Horizontal Boring and Milling Machine Tool Storage Manipulator for Example

    Institute of Scientific and Technical Information of China (English)

    丁鹏超

    2015-01-01

    机械手升降机通过液动机带动滚珠丝杠转动,带动手架运动,再由减速和离合器吸合丝杠制动,使手架准确停在换刀位置,良好的结构设计能够实现刀库中刀具的快速更换,提高机床的加工效率。随着数控机床的普及应用,机械加工的自动化程度大大提高,数控机床发展成了当今普遍应用的一种更新、更先进的制造设备。%This paper introduced the working principle of the manipulator of lifting mechanism and analyzed the design and calculation for structure,ball screw was driven to rotate through liquid motivation and then the hand aircraft was driven to move,and through decelerating and the actuation of clutch,the screw was driven to move,which made hand aircraft parked in tool changing position accurately,favorable design of structure can make it more possible to quick replace tool inside tool storage quickly and improve the machining efficiency of machine tool. With the popularity of CNC machine tool,the degree of automation of mechanical processing has been greatly improved,numerical control machine tool has developed into newer and more advanced manufacturing equipment which is widely applied today.

  9. 按极限进给量切削时大型数控龙门镗铣床立柱端面的作用力及其分布%Forces Exerted upon the End Plane of the Column of the Large-duty NC Plano Milling and Boring Machine during Cutting at the Limit Feed, and Their Distribution

    Institute of Scientific and Technical Information of China (English)

    徐大伟

    2002-01-01

    确定极限进给量切削时大型数控龙门镗铣床立柱端面的作用力是开展该类机床立柱结构强度及刚度校验的必要前提.本文着重介绍某大型数控镗铣床主轴处于横梁端部位置并以极限进给量切削时立柱端面的作用力之计算方法.本文所涉内容对同类型机床的立柱等大件结构的设计、强度和刚度校验等具有实际参考价值.

  10. 杭州海达大厦砂质地层和粘土层钻孔灌注桩施工工艺%Construction Technology of Bored Grouting Pile Applied in Sand and Clay Formation in Haida Building in Hangzhou

    Institute of Scientific and Technical Information of China (English)

    苏新法

    2006-01-01

    砂质地层和粘土层是钻孔灌注桩施工难度较大的地层,通过杭州海达大厦桩基工程实例,介绍砂质地层的扩孔保径和粘土层的特殊成孔工艺,解决了砂质地层缩径和粘土层钻进清渣难的问题.

  11. Rapid determination of dichlorvos, methamidophos and chlorpyrifos in semen coicis for exit by gas chromatography with large-bore capillary column%大口径毛细管-气相色谱法快速测定出口薏苡仁中敌敌畏、甲胺磷、毒死蜱残留量

    Institute of Scientific and Technical Information of China (English)

    张泽楷; 伍庆; 王兴宁

    2009-01-01

    目的:建立大口径毛细管-气相色谱快速测定出口薏苡仁中敌敌畏、甲胺磷、毒死蜱农药残留量的方法.方法:采用OV-1701(30 m×0.53 mm×0.53 μm)分离和火焰光度检测器(FPD)检测,外标法计算含量.结果:线性范围:0.1~2.0μg/mL,加标回收率:82.64%~97.58%,相对标准偏差(RSDl:1.57%~5.35%,检出限:0.004~0.032 mg/kg.结论:本方法快速、简便、准确,适用于测定薏苡仁中敌敌畏、甲胺磷、毒死蜱农药残留.

  12. 京杭运河二通道钱塘江出口船闸闸门涌潮作用力研究%Bore pressure on the 2nd passage gate of ship lock of Jinghang Great Canal crossing the Qiantang River

    Institute of Scientific and Technical Information of China (English)

    杨火其; 伍冬领; 周建炯; 金凯良

    2006-01-01

    分析了二通道钱塘江出口处水域设计条件下涌潮高度与潮差、低潮位的关系,采用低潮位下50 a一遇的涌潮高度作为船闸闸门涌潮作用力试验的边界条件,得到船闸闸门所受的涌潮作用力和分布特征,涌潮对船闸闸门的最大作用力发生在低潮位附近,引航道喇叭形的出口将会加大涌潮对闸门的作用力.

  13. 让枯燥无味的数学变得“有趣、有味、有惑”——Matlab中的音乐合成%Making Boring Math Interesting, Sapid, and Intriguing——Animation and Music Synthesis by Matlab

    Institute of Scientific and Technical Information of China (English)

    易昆南; 李慧; 赵澍源

    2014-01-01

    探讨了在Matlab实验教学中,通过设计问题“音乐与数学有关吗?”揭示了音乐信号是由一系列振幅和频率不一的正弦波叠加且带有不同包络修饰形成的,进而采用曲线拟合来定包络.以傅里叶变换来研究音乐的合成,从数学的角度生动直观的展示了数学与音乐结合的无穷魅力,激发学生的学习兴趣,以提升学生综合素质与创新能力.

  14. Study on Treatment of Low Concentration Nitrobenzene by MBBR Process Using Large Bore Reticulated Polyurethane Carrier%大孔网状聚氨酯载体MBBR工艺处理低浓度硝基苯废水实验研究

    Institute of Scientific and Technical Information of China (English)

    冀巍

    2014-01-01

    利用大孔网状聚氨酯载体在MBBR工艺条件下,研究了系统挂膜与启动过程,同时利用挂膜成熟稳定的载体进行低浓度硝基苯废水处理实验.研究结果表明,在20℃条件下培养的活性污泥生长状况良好,挂膜速度快,生物膜厚度大,耐冲击负荷.在MBBR反应时间24 h、材料投加量为1/4、硝基苯初始浓度为2.095mg/L的条件下,处理低浓度硝基苯废水的效果最好,CODcr去除率为92.58%,硝基苯去除率为49.82%.

  15. APPLICATION OF GUIDED-BORING TECHNOLOGY OF PNEUMATIC DOWN-THE-HOLE HAMMER IN MEGALITHIC AND COARSE-SAND SEE RECLAMATION%巨石、中粗砂填海区风动潜孔锤引孔钻进工艺应用的研究

    Institute of Scientific and Technical Information of China (English)

    王平; 彭晓阳; 经明; 刘广忠

    2002-01-01

    通过成功地解决深圳市妈湾电厂(二期)基础工程H型桩沉入困难问题,使用各种风动潜孔锤在巨石、中粗砂填海区进行了引孔钻进工艺的试验研究及应用,对风动潜孔锤钻进工艺及其机具的使用作了进一步的分析研究,提出了风动潜孔锤使用过程中工艺方面的改进措施.

  16. Geology, Bedrock, Data contains 10 foot elevation contours (1 foot in some areas) showing the approximate bedrock surface elevation within McLain State Park, Houghton, County, Michigan. Contours were generated with the Surfer 12 software package using soil test borings and, Published in 2014, Not Applicable scale, Michigan Coastal Zone Management Program.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Geology, Bedrock dataset, published at Not Applicable scale, was produced all or in part from Field Survey/GPS information as of 2014. The source is Michigan...

  17. Propriétés structurales et optiques de nanostructures III-N semiconductrices à grand gap : nanofils d'AlxGa1-xN synthétisés par épitaxie par jets moléculaires et nanostructures de nitrure de bore.

    OpenAIRE

    2013-01-01

    This work focuses on structural and optical properties of III-nitrides wide-band gap semiconductors (AlxGa1-xN et h-BN), emitting in the ultraviolet range (4-6 eV). Nano-objects properties being modified by dimensional reduction, this work was mostly focused on the study of nanostructures of these materials (AlN and AlxGa1-xN nanowires, BN nanotubes and nanosheets). Careful search for correlation between their structure and luminescence has also been carried out. Concerning AlxGa1-xN material...

  18. 全断面掘进机(TBM)刀盘总推进力的分析计算%Analysis and Calculation to the General Propping Force of the Cutter Head of the Full-Face Tunnel Boring Machine (TBM)

    Institute of Scientific and Technical Information of China (English)

    朱齐平; 刘希太; 潘存治

    2006-01-01

    探讨了在不同的地质条件下TBM刀盘总推进力的设计计算方法,有利于优化TBM的结构参数和总装机功率,提高TBM适应不同地质条件的能力,并以ROBBINS(美)公司MB264-311型TBM为例进行了模拟计算,证明该计算方法 正确有效.

  19. 泥浆护壁钻(冲)孔灌注桩成桩质量检验如何保障和提高灌注桩的施工质量讲座(六)%Quality Test of Slurry Wall Cast-in-situ Bored Piles Lecture 6 of "Assurance & Improvement of Construction Quality of Cast-in-situ Pile"

    Institute of Scientific and Technical Information of China (English)

    佟世祥

    2004-01-01

    @@ 1桩基工程的检验 桩基工程为地下隐蔽工程,为确保其工程质量,从施工开始就应按工序严格进行监控和检测,并认真做好相关记录,以便及时发现问题和采取相应的处理措施,进而对桩基工程质量作出整体的综合性评价.

  20. Analyzing Reliability of Old Bore in Utilization by Computing Magnetite(MFe)on Regression Equation%用回归方程计算的磁性铁(MFe)分析老钻孔在利用中的可靠性

    Institute of Scientific and Technical Information of China (English)

    王雅林

    2001-01-01

    通过对用回归方程计算的磁性铁(MFe)的验证情况,说明对于矿山地质工作,在老钻孔的利用上,用回归方程计算的结果可靠性低,不能用于直接指导生产,至于今后如何利用矿山现有的老钻孔资料,应重新考虑新的方法.