WorldWideScience

Sample records for well bore damage

  1. 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...

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  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. 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.

  8. 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.

  9. 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.

  10. 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.

  11. U.S. Geological Survey Combined Well-Bore Flow and Depth-Dependent Water Sampler

    Science.gov (United States)

    Izbicki, John A.; Christensen, Allen H.; Hanson, Randall T.; Martin, Peter; Crawford, Steven M.; Smith, Gregory A.

    1999-01-01

    The U.S. Geological Survey has developed a combined well-bore flow and depth-dependent sample collection tool. It is suitable for use in existing production wells having limited access and clearances as small as 1 inch. The combination of well-bore flow and depth-dependent water-quality data is especially effective in assessing changes in aquifer properties and water quality with depth. These are direct measures of changes in well yield and ground-water quality with depth under actual operating conditions. Combinations of other geophysical tools capable of making these measurements, such as vertical-axis current meters used with wire-line samplers, are commercially available but these tools are large and can not easily enter existing production wells.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. Development of an electromagnetic imaging system for well bore integrity inspection

    Science.gov (United States)

    Plotnikov, Yuri; Wheeler, Frederick W.; Mandal, Sudeep; Climent, Helene C.; Kasten, A. Matthias; Ross, William

    2017-02-01

    State-of-the-art imaging technologies for monitoring the integrity of oil and gas well bores are typically limited to the inspection of metal casings and cement bond interfaces close to the first casing region. The objective of this study is to develop and evaluate a novel well-integrity inspection system that is capable of providing enhanced information about the flaw structure and topology of hydrocarbon producing well bores. In order to achieve this, we propose the development of a multi-element electromagnetic (EM) inspection tool that can provide information about material loss in the first and second casing structure as well as information about eccentricity between multiple casing strings. Furthermore, the information gathered from the EM inspection tool will be combined with other imaging modalities (e.g. data from an x-ray backscatter imaging device). The independently acquired data are then fused to achieve a comprehensive assessment of integrity with greater accuracy. A test rig composed of several concentric metal casings with various defect structures was assembled and imaged. Initial test results were obtained with a scanning system design that includes a single transmitting coil and several receiving coils mounted on a single rod. A mechanical linear translation stage was used to move the EM sensors in the axial direction during data acquisition. For simplicity, a single receiving coil and repetitive scans were employed to simulate performance of the designed receiving sensor array system. The resulting electromagnetic images enable the detection of the metal defects in the steel pipes. Responses from several sensors were used to assess the location and amount of material loss in the first and second metal pipe as well as the relative eccentric position between these two pipes. The results from EM measurements and x-ray backscatter simulations demonstrate that data fusion from several sensing modalities can provide an enhanced assessment of flaw

  17. 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.

  18. Boundary conditions for convergent radial tracer tests and effect of well bore mixing volume

    Science.gov (United States)

    Zlotnik, Vitaly A.; David Logan, J.

    Convergent radial flow tracer tests have a complex spatial nonaxial transport structure caused by the flow in the vicinity of the injection well and its finite mixing volume. The formulation of the boundary value problem, and especially the treatment of the boundary conditions at the injection well, is nontrivial. Hodgkinson and Lever [1983], Moench [1989, 1991], and Welty and Gelhar [1994] have developed different models and methods for the analysis of breakthrough curves in the extraction well. To extend interpretation techniques to breakthrough curves in the zone between injection and extraction wells, an analysis of conventional transport models is given, and improved boundary conditions are formulated for a convergent radial tracer test problem. The formulation of the boundary conditions is based upon a more detailed analysis of the kinematic flow structure and tracer mass balance in the neighborhood of the injection well. Two practical applications of revised boundary conditions for field data analysis are given. First, the note explains anomalous high well bore mixing volumes of injection wells found by Cady et al. [1993] and allows one to establish the role of mixing versus other processes (retardation, matrix diffusion, etc.). Second, it is shown that the improper use of Moench's [1989] model can produce bias in the characteristics of breakthrough curves in the extraction well under conditions that involve a significant mixing factor in the injection well. A numerical example indicates an error in peak concentrations on a breakthrough curve by as much as 70% and in peak arrival time by 10% for Peclet numbers Pe=102. The effect becomes slightly less significant for Pe=1.

  19. 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%.

  20. 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.

  1. INFLUENCE OF WINE ACID ON RHEOLOGICAL PROPERTIES OF WELL BORE CEMENT SLURRIES AND HARDENED CEMENT PROPERTIES

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    1989-12-01

    Full Text Available Adaptation of commercial types of domestic cements for use in cementing the deep wells is a process by which Yugoslav oil industry tends to solve problems of completion of those wells independently. In order to design a domestic, cheep and effective retarder, tests of applicability of wine acid on cement slurries have been carried out. Besides examining the necessary wine acid content to achieve desirable Theological properties, the influence of this additive on properties of hardened cement samples has been tested too (the paper is published in Croatian.

  2. 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

  3. Final Scientific/Technical Report for "Nanite" for Better Well-Bore Integrity and Zonal Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Veedu, Vinod [Oceanit Laboratories, Inc., Honolulu, HI (United States); Hadmack, Michael [Oceanit Laboratories, Inc., Honolulu, HI (United States); Pollock, Jacob [Oceanit Laboratories, Inc., Honolulu, HI (United States); Pernambuco-Wise, Paul [Oceanit Laboratories, Inc., Honolulu, HI (United States); Ah Yo, Derek [Oceanit Laboratories, Inc., Honolulu, HI (United States)

    2017-05-30

    Nanite™ is a cementitious material that contains a proprietary formulation of functionalized nanomaterial additive to transform conventional cement into a smart material responsive to pressure (or stress), temperature, and any intrinsic changes in composition. This project has identified optimal sensing modalities of smart well cement and demonstrated how real-time sensing of Nanite™ can improve long-term wellbore integrity and zonal isolation in shale gas and applicable oil and gas operations. Oceanit has explored Nanite’s electrical sensing properties in depth and has advanced the technology from laboratory proof-of-concept to sub-scale testing in preparation for field trials.

  4. Pore pressure prediction and well bore stability analysis in Lower Paleozoic shale formation, N Poland

    Science.gov (United States)

    Słota-Valim, Małgorzata

    2017-04-01

    Pore pressure and wellbore stability sometimes pose a serious challenge while drilling, especially through rock formations of reduced strength or through intervals where abnormally high pore pressure was formed. Lack of prediction of pore pressure and lack of wellbore stability analysis introduce an element of uncertainty in selection of drilling fluid density. Too low density of drilling fluid can lead to uncontrolled flow of the reservoir fluid to the wellbore (kicks), washouts and occurrence of cavern like structures called breakouts. On the other hand too high density can lead to formation fracturing and further fluid loss. Therefore wellbore stability loss frequently prolongs the operating time, rising the costs of the drilling and in severe cases may end up well abandons loss. The above mentioned complications can be avoided or greatly reduced by reliable analysis of drilling conditions with the aspects to geomechanical characteristics of drilled rock formations. This study presents the results of analysis of pore pressure performed with the use of commonly used in oil industry methods. The analysis of pore pressure was carried out in almost entire profile of four boreholes drilled through lower Paleozoic shales, deposited in the southern part of the Baltic Basin. In addition wellbore stability analysis was performed in the well with most complete geomechanical input data base. Obtained results helped identifying intervals with elevated pore pressure could pose a risk during drilling operation. Elaborated 1D geomechanical model provides safe mud weight window helping to reduce the instabilities risk and constitute a great tool for geomechanical model validation.

  5. Records of wells, test borings, and some measured geologic sections near the Western New York Nuclear Service Center, Cattaraugus County, New York

    Science.gov (United States)

    Bergeron, M.P.

    1985-01-01

    The Western New York Nuclear Service Center (WNYNSC) is a 3 ,336-acre tract of land in northern Cattaraugus County, NY, about 30 mi south of Buffalo. In 1963, 247 acres within the WNYNSC was developed for a nuclear-fuel reprocessing plant and ancillary facilities, including (1) a receiving and storage facility to store fuel prior to reprocessing, (2) underground storage tanks for liquid high-level radioactive wastes from fuel reprocessing, (3) a low-level wastewater treatment plant, and (4) two burial grounds for shallow burial of solid radioactive waste. A series of geologic and hydrologic investigations was done as part of the initial development and construction of the facilities by numerous agencies during 1960-62; these produced a large quantity of well data, some of which are difficult to locate or obtain. This report is a compilation of well and boring data collected during this period. The data include records of 236 wells, geologic logs of 145 wells and 167 test borings, and descriptions of 20 measured geologic sections. Two oversized maps show locations of the reported data. (USGS)

  6. Determination of mechanical damage from wells under oil and gas flow condition; Determinacao de dano mecanico em pocos sob condicao de escoamento de oleo e gas

    Energy Technology Data Exchange (ETDEWEB)

    Marques, J. B.D. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Trevisan, O. V. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

    2008-07-01

    The well bore effect is one of the most difficult variables obtained from well test analysis under two-phase condition. The presence of the gas in a well inserted in reservoir, which operates under gas drive solution, hinders the development of the analytical model to determine the mechanical damage. It is one of the reasons of the using the single phase well test analysis methodologies become suitable to the multiphase cases. The determination of the well bore effect is justified; therefore it is possible to work over in the well in order to determinate the real potential productive. The main objective of this work is to reevaluate a method of determination of the mechanical damage gotten from a well test under two-phase condition. In this work a simplified model of reservoir simulation is constructed in a commercial simulator in order to validate the methodology. The refinement of the blocks near to the well adopted in the simulation is a good representation of the well mechanical damage which occurs in a homogeneous reservoir. The types of well test analysis used in this work are two: drawdown and buildup test. The results gotten for this methodology, as will be shown, are excellent quality and the model of simulation presented here can be used for other analytical methods studies in order to determinate the mechanical damage or other variable of the reservoir. (author)

  7. On bore collapse

    Science.gov (United States)

    Yeh, Harry H.; Ghazali, A.

    1988-06-01

    Using the laser-induced fluorescent method, the transition process from bore to runup mode, i.e., "bore collapse," is investigated experimentally. The observed process appears to be different from both previous analytical and numerical predictions. The results indicate that momentum exchange takes place between the incident bore and the quiescent water body along the shoreline. Turbulence generated in a bore nearshore is highly three-dimensional and sporadic. Very close to the shore, turbulence is advected with the bore front, and consequently, the bore collapse process involves strong turbulent action onto the dry beach bed.

  8. 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.

  9. 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...

  10. Mechanisms of formation damage in matrix-permeability geothermal wells

    Energy Technology Data Exchange (ETDEWEB)

    Bergosh, J.L.; Wiggins, R.B.; Enniss, D.O.

    1982-04-01

    Tests were conducted to determine mechanisms of formation damage that can occur in matrix permeability geothermal wells. Two types of cores were used in the testing, actual cores from the East Mesa Well 78-30RD and cores from a fairly uniform generic sandstone formation. Three different types of tests were run. The East Mesa cores were used in the testing of the sensitivity of core to filtrate chemistry. The tests began with the cores exposed to simulated East Mesa brine and then different filtrates were introduced and the effects of the fluid contrast on core permeability were measured. The East Mesa cores were also used in the second series of tests which tested formation sandstone cores were used in the third test series which investigated the effects of different sizes of entrained particles in the fluid. Tests were run with both single-particle sizes and distributions of particle mixes. In addition to the testing, core preparation techniques for simulating fracture permeability were evaluated. Three different fracture formation mechanisms were identified and compared. Measurement techniques for measuring fracture size and permeability were also developed.

  11. 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...

  12. Double diameter boring tool

    Science.gov (United States)

    Ashbaugh, Fred N.; Murry, Kenneth R.

    1988-12-27

    A boring tool and a method of operation are provided for boring two concentric holes of precision diameters and depths in a single operation. The boring tool includes an elongated tool body, a shank for attachment to a standard adjustable boring head which is used on a manual or numerical control milling machine and first and second diametrically opposed cutting edges formed for cutting in opposite directions. The diameter of the elongated tool body is substantially equal to the distance from the first cutting edge tip to the axis of rotation plus the distance from the second cutting edge tip to the axis of rotation. The axis of rotation of the tool is spaced from the tool centerline a distance substantially equal to one-half the distance from the second cutting edge tip to the axis of rotation minus one-half the distance from the first cutting edge tip to the axis of rotation. The method includes the step of inserting the boring tool into the boring head, adjusting the distance between the tool centerline and the tool axis of rotation as described above and boring the two concentric holes.

  13. 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.

  14. 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

  15. Why are some microorganisms boring?

    Science.gov (United States)

    Cockell, Charles S; Herrera, Aude

    2008-03-01

    Microorganisms from diverse environments actively bore into rocks, contributing significantly to rock weathering. Carbonates are the most common substrate into which they bore, although there are also reports of microbial borings into volcanic glass. One of the most intriguing questions in microbial evolutionary biology is why some microorganisms bore. A variety of possible selection pressures, including nutrient acquisition, protection from UV radiation and predatory grazing could promote boring. None of these pressures is mutually exclusive and many of them could have acted in concert with varying strengths in different environments to favour the development of microorganisms that bore. We suggest that microbial boring might have begun in some environments as a mechanism against entombment by mineralization.

  16. 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.

  17. Cam-controlled boring bar

    Science.gov (United States)

    Glatthorn, Raymond H.

    1986-01-01

    A cam-controlled boring bar system (100) includes a first housing (152) which is rotatable about its longitudinal axis (154), and a second housing in the form of a cam-controlled slide (158) which is also rotatable about the axis (154) as well as being translatable therealong. A tool-holder (180) is mounted within the slide (158) for holding a single point cutting tool. Slide (158) has a rectangular configuration and is disposed within a rectangularly configured portion of the first housing (152). Arcuate cam slots (192) are defined within a side plate (172) of the housing (152), while cam followers (194) are mounted upon the cam slide (158) for cooperative engagement with the cam slots (192). In this manner, as the housing (152) and slide (158) rotate, and as the slide (158) also translates, a through-bore (14) having an hourglass configuration will be formed within a workpiece (16) which may be, for example, a nuclear reactor steam generator tube support plate.

  18. Maneuvering impact boring head

    Science.gov (United States)

    Zollinger, W. Thor; Reutzel, Edward W.

    1998-01-01

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure.

  19. Evaluation of Formation Damage and Assessment of Well Productivity of Oredo Field, Edo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Omotara O. Oluwagbenga

    2015-02-01

    Full Text Available Formation damage canincurconsiderable cost for remediation and deferred production. Thorough understanding of the formation damage mechanisms, stringent measures for its control and prevention, and effective and efficient treatments are the keys for optimum production strategies for oil and gas fields. WELL 4X was investigated in this study to properly diagnosed and evaluate productivity in OREDO FIELD and Bottom Hole Pressure survey was used from Bottom Hole Pressure analysis in addition to the information of the well production history and reservoir data available to determine and assess the extent of the formation damage in the well. The WELL 4X was stimulated using Acid Foam Diversion Techniques to enhance reservoir productivity and increase economic operations. The stimulation job done on the well showed a peak increase of production from 850 bbl/day to 3200 b/d before it declined to 2150 bbl/day, and finally maintained an average stabilized rate of 2000 bbl/day. It has to be established that the treatment method on WELL 4X using Acid Foam Diversion Techniques and the Bottom Hole Pressure survey conducted on the WELL 4X in OREDO FIELD is found to be efficient in the determination and evaluation of formation damage.

  20. 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

  1. Photoelectric Inspecting of Artillery Bore

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; MA Hong; BAI Su-ping; YAN Yu-feng

    2008-01-01

    A photoelectric equipment for inspecting artillery bore is composed of digital display grating sensor and data processing with computer. It can replace the traditional mechanical measurer and realize the automatic inspection of artillery bore. Introduced are briefly the working principles and analysis of this device.

  2. 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.

  3. Large-bore pipe decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  4. Numerical Analysis of Doublet Wells for Cold Energy Storage on Heat Damage Treatment in Deep Mines

    Institute of Scientific and Technical Information of China (English)

    HE Man-chao; ZHANG Yi; GUO Dong-ming; QIAN Zeng-zhen

    2006-01-01

    Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Machine Systems (HEMSs), to store cold energy is a key to solve the heat damage problems in deep mines. Based on the geological conditions, thermodynamic and hydraulic parameters of Jiahe Mine, the isotherms in the period of cold energy storage and refrigeration and the volumes of cold water within different temperature ranges of the cold energy storage well were numerically analyzed. The results show that 1) with the same pumped and injected water volumes, the lower the temperature of injected water is, the larger the volume of cold water in the cold energy storage well is. With the larger volume, the effect of cold energy storage is better. 2) the larger the volumes of pumped and reinjected water are, the larger the volume of cold water from the cold energy storage well is. With the larger volume, the effect of refrigeration is better. And 3) without disturbance, the volume and temperature of cold water in the cold energy storage well can keep unchanged or have only a little change for a long time. Therefore the technology of doublet wells for cold energy storage is feasible and the cold energy storage aquifers can meet the requirement of the technology.

  5. 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.

  6. Characterization of sulphate scaling formation damage from laboratory measurements to predict well productivity decline

    Energy Technology Data Exchange (ETDEWEB)

    Bedrikovetsky, P.G.; Monteiro, R. [Universidade Estadual do Norte Fluminense (UENF), Macae, RJ (Brazil). Lab. de Engenharia e Exploracao de Petroleo (LENEP); Moraes, G.P. [Centro Federal de Educacao Tecnologica (CEFET), Macae, RJ (Brazil). Unidade de Ensino Descentralizada (UNED-Macae); Lopes Junior, R.P. [PETROBRAS, Macae, RJ (Brazil). Unidade de Negocios da Bacia de Campos; Rosario, F.F.; Bezerra, M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Barium sulphate scaling is a chronicle disaster during offshore waterflood project where injected and formation waters are incompatible, and their mixing causes salt precipitation. It was detected in several fields of Campos Basin. The mathematical model for sulphate precipitation contains two empirical parameters: the reaction kinetics coefficient that characterizes how fast the precipitation is going on, and the formation damage coefficient showing which permeability impairment the precipitation causes. Knowledge of these two parameters is essential for reliable prediction of the well productivity decline during sea/produced water injection. These parameters are empirical and depend on rock properties; therefore they should be determined from laboratory coreflood tests by forcing the injected and formation waters through rock. Despite these tests have been presented in numerous papers, there were no attempts to determine the model coefficients from laboratory data in order to perform the laboratory-data-based reservoir simulation. A new method for simultaneous determination of both coefficients from the coreflood data is developed. The method determines the kinetic coefficient from ion concentration measurements at the core effluent; then the formation damage coefficient is determined from the pressure drop measurements. The laboratory procedures are routine, the data are available in the literature. The method is based on inverse problem for reactive flow in rocks. The inverse solution is obtained from the exact quasi steady state concentration profile during coreflood. The proposed method furnishes unique values for two coefficients, and the solution is stable with respect to small perturbations of the measured values. The laboratory data on sulphate scaling by CENPES/PETROBRAS, Brazil, and Herriot-Watt University, UK, were treated, and the data were used for prediction of productivity decline in Campos Basin reservoir. The well behaviour forecast and history

  7. Energetic aspects of boring tools wear

    Directory of Open Access Journals (Sweden)

    Lazarová Edita

    2002-03-01

    Full Text Available In the process of rock desintegration a boring tool is subjected to the wear. From a viewpoint of the bit wear, changes on the contact of operating tool with rock at its one-shot and rerun load or overload by external forces are technically significant. Theis change results in the degradation of bit working properties and the output of desintegration also decreases. In the major part of cases, together with the bit wear, the contact area of a tool with a rock massifs enhanced and this fact causes an increase of fines (dust creation during the desintegration. The wear is always connected with a friction, forces action, deformation, damage, and the increased mechanical work consumption. As to energetic aspects of bit wear, the wear was observed as a function of bore length and in the most of cases as a dependence of the operating time. A linear dependence between the wear intensity (bit wear per unit of bore length and the specific energy of desintegration (energy consumed per volume unit of desintegrated rock was experimentally verified. Thus, the changes of bit wear can be implicitly observed by monitoring the specific energy. At the same time, the specific energy is a function of input parameters of the desintegration process and in the field of applicable external forces it shows an extreme (minimum. Therefore, the specific energy is useful for the extreme optimisation of the rock desintegration process from the viewpoint of the bit wear. It was mathematically proven that the tool output at the desintegration exponentially decreases with the amount of work consumed in the rock desintegration. The derivation of this knowledge comes out from the Krendelev equation.

  8. Interface modeling to predict well casing damage for big hill strategic petroleum reserve.

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L.; Park, Byoung Yoon

    2012-02-01

    Oil leaks were found in well casings of Caverns 105 and 109 at the Big Hill Strategic Petroleum Reserve site. According to the field observations, two instances of casing damage occurred at the depth of the interface between the caprock and top of salt. This damage could be caused by interface movement induced by cavern volume closure due to salt creep. A three dimensional finite element model, which allows each cavern to be configured individually, was constructed to investigate shear and vertical displacements across each interface. The model contains interfaces between each lithology and a shear zone to examine the interface behavior in a realistic manner. This analysis results indicate that the casings of Caverns 105 and 109 failed by shear stress that exceeded shear strength due to the horizontal movement of the top of salt relative to the caprock, and tensile stress due to the downward movement of the top of salt from the caprock, respectively. The casings of Caverns 101, 110, 111 and 114, located at the far ends of the field, are predicted to be failed by shear stress in the near future. The casings of inmost Caverns 107 and 108 are predicted to be failed by tensile stress in the near future.

  9. Study on Skin Factor and Productivity of Horizontal Well after Acidizing with Nonuniform Damage

    Directory of Open Access Journals (Sweden)

    Lin Yuan

    2015-01-01

    Full Text Available Horizontal well (HW was divided into several elements after acidizing. In each element, there would exist a composite zone that was made up of damage zone (DZ and acidizing zone (AZ. Local skin factor after acidizing was used to describe the resistance in each composite zone. The models for local skin factor and productivity of HW were created using the method of equivalent filtration resistance and displacement between two similar flow modes. According to the solution of the models, type curves of skin factor and production-increasing ratio after acidizing were illustrated, and the effect of different parameters in DZ and AZ on distribution of skin factor and production-increasing ratio after acidizing were discussed. The present model has a significant guide on the practice of acidizing technology.

  10. 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.

  11. 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.

  12. Can tasks be inherently boring?

    Science.gov (United States)

    Charney, Evan

    2013-12-01

    Kurzban et al. argue that the experiences of "effort," "boredom," and "fatigue" are indications that the costs of a task outweigh its benefits. Reducing the costs of tasks to "opportunity costs" has the effect of rendering tasks costless and of denying that they can be inherently boring or tedious, something that "vigilance tasks" were intentionally designed to be.

  13. 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)

  14. A Study of the Occurrence of Mesospheric Bore at the Equatorial Region in Brazil

    Science.gov (United States)

    Medeiros, A. F.; Fechine, J.; Buriti, R. A.; Takahashi, H.; Gobbi, D.

    An all-sky CCD imager capable of measuring wave structure in the OH, O2 and OI (557.7 nm) airglow emissions was operated in the equatorial region at São João do Cariri (Cariri), Brazil, (7 S, 36 W), in collaboration with Instituto Nacional de Pesquisas Espaciais (INPE). A study of the occurrence of mesospherics bores was done. This work used data from September 2000 to September 2002, also were used photometer data. It was detected 64 events like mesospheric bore during this observation period. The analyses did not show a seasonal behavior. It was analyzed as well the following aspects: multiples bore case in the same night, parameters observed of wave train of the bore. The high activity of gravity waves was observed before bore events in most of the case corroborating the generation mechanism proposed by Dewan and Picard (1998, 2001). Some nights presented more than two bore events.

  15. Discussion boards: boring no more!

    Science.gov (United States)

    Adelman, Deborah S; Nogueras, Debra J

    2013-01-01

    Creating discussion boards (DBs) that capture student imaginations and contain meaningful interactions can be a difficult process. Traditional DBs use a question-and-answer format that often is boring for both the student and instructor. The authors present creative approaches to DBs that result in lively debates and student-to-student and student-to-faculty interactions, including role playing, blogging, wikis, and the use of voice.

  16. Successive impact of tidal bores on sedimentary processes: Arcins channel, Garonne River

    Science.gov (United States)

    Reungoat, David; Leng, Xinqian; Chanson, Hubert

    2017-03-01

    A tidal bore is a hydrodynamic shock, propagating upstream as the tidal flow turns to rising, with macro-tidal conditions in a funnel shaped system with shallow waters. The tidal bore of the Garonne River was extensively investigated in the Arcins channel between 2010 and 2013, typically over one to two days. In 2015, new field measurements were repeated systematically at the same site on 29 August-1 September 2015 and on 27 October 2015. The nature of the observations was comprehensive, encompassing hydrodynamics and turbulence, as well as sediment properties and transport. The tidal bore occurrence had a marked effect on the velocity and suspended sediment field, including a rapid flow deceleration and flow reversal during the bore passage, with very large suspended sediment concentrations (SSCs) during the passage of the tidal bore front and early flood tide, as well as very large suspended sediment flux during the very early flood tide. The suspended sediment concentration (SSC) data indicated a gradual increase in initial mean SSC estimate prior to the bore from 29 August to 1 September 2015. A comparison between suspended sediment flux data showed very significant suspended sediment flux on the first day of tidal bore occurrence, with a decreasing magnitude over the next three days. The data suggested a two-stage bed scour process: at each tidal bore event, surface erosion occurred initially, in the form of stripping; the first stage was followed by delayed mass erosion, occurring about 5-15 min after the tidal bore.

  17. 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.

  18. 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.

  19. 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

  20. A new method of damage determination in geothermal wells from geothermal inflow with application to Los Humeros, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Aragon, A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Moya, S. L [Centro Nacional de Investigacion y Desarrollo Tecnologico, Cuernavaca, Morelos (Mexico); Garcia-Gutierrez, A; Arellano, V [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2008-10-15

    Geothermal inflow type curves were obtained for different values of well damage (i.e., inflow performance relationships). The method was evaluated by diagnosing the damage of thirteen producing wells in the Los Humeros, Puebla, Mexico geothermal field. Permeability determinations were carried out for these wells and their productivity indices were estimated. Comparison of the diagnoses made via damage effects against the results of field pressure tests showed that the maximum difference between both approaches is on the order of 0.7 damage units. The methodology allows reservoir characterization along its productive life, since several production tests are carried out while the reservoir is producing. The data obtained from production tests are used to determine the damage effect and permeability of the rock formation. Previously the damage (skin factor) could only be determined from the analyses of transient pressure tests. [Spanish] Se presenta la obtencion de curvas-tipo de influjo geotermico para diferentes valores de dano, y se demuestra su aplicacion en los analisis de produccion de pozos geotermicos determinando el dano en trece pozos del campo geotermico de Los Humeros, Puebla, Mexico. Tambien se hicieron determinaciones de la permeabilidad en las zonas de produccion de estos pozos y de sus respectivos indices de productividad. Se compararon los resultados del valor de dano obtenido con la metodologia propuesta, con los valores de dano obtenidos a partir de pruebas de presion, encontrando que las diferencias maximas entre ambas tecnicas es del orden de 0.7 unidades de dano. La presente metodologia permite la caracterizacion del yacimiento a lo largo de su vida productiva a partir de las mediciones de las pruebas de produccion efectuadas en los pozos. La metodologia propuesta es innovadora porque anteriormente el dano solamente se podia determinar a partir de los analisis de las mediciones de la pruebas de presion.

  1. Investigation of reactive-ion-etch-induced damage of InP/InGaAs multiple quantum wells by photoluminescence

    DEFF Research Database (Denmark)

    Steffensen, O. M.; Birkedal, Dan; Hanberg, J.

    1995-01-01

    The effects of CH4/H2 reactive ion etching (RIE) on the optical properties of an InP/InGaAs multiple-quantum-well structure have been investigated by low-temperature photoluminescence (PL). The structure consisted of eight InGaAs quantum wells, lattice matched to InP, with nominal thicknesses of 0.......5, 1, 2, 3, 5, 10, 20, and 70 monolayers, respectively, on top of a 200-nm-thick layer of InGaAs for calibration. The design of this structure allowed etch-induced damage depth to be obtained from the PL spectra due to the different confinement energies of the quantum wells. The samples showed...... no significant decrease of luminescence intensity after RIE. However, the observed shift and broadening of the PL peaks from the quantum wells indicate that intermixing of well and barrier material increased with etch time. ©1995 American Institute of Physics....

  2. Casing pipe damage detection with optical fiber sensors: a case study in oil well constructions

    Science.gov (United States)

    Zhou, Zhi; He, Jianping; Huang, Minghua; He, Jun; Ou, Jinping; Chen, Genda

    2010-04-01

    Casing pipes in oil well constructions may suddenly buckle inward as their inside and outside hydrostatic pressure difference increases. For the safety of construction workers and the steady development of oil industries, it is critically important to measure the stress state of a casing pipe. This study develops a rugged, real-time monitoring, and warning system that combines the distributed Brillouin Scattering Time Domain Reflectometry (BOTDR) and the discrete fiber Bragg grating (FBG) measurement. The BOTDR optical fiber sensors were embedded with no optical fiber splice joints in a fiber reinforced polymer (FRP) rebar and the FBG sensors were wrapped in epoxy resins and glass clothes, both installed during the segmental construction of casing pipes. In-situ tests indicate that the proposed sensing system and installation technique can survive the downhole driving process of casing pipes, withstand a harsh service environment, and remain in tact with the casing pipes for compatible strain measurements. The relative error of the measured strains between the distributed and discrete sensors is less than 12%. The FBG sensors successfully measured the maximum horizontal principal stress with a relative error of 6.7% in comparison with a cross multi-pole array acoustic instrument.

  3. Casing Pipe Damage Detection with Optical Fiber Sensors: A Case Study in Oil Well Constructions

    Directory of Open Access Journals (Sweden)

    Zhi Zhou

    2010-01-01

    Full Text Available Casing pipes in oil well constructions may suddenly buckle inward as their inside and outside hydrostatic pressure difference increases. For the safety of construction workers and the steady development of oil industries, it is critically important to measure the stress state of a casing pipe. This study develops a rugged, real-time monitoring, and warning system that combines the distributed Brillouin Scattering Time Domain Reflectometry (BOTDR and the discrete fiber Bragg grating (FBG measurement. The BOTDR optical fiber sensors were embedded with no optical fiber splice joints in a fiber-reinforced polymer (FRP rebar and the FBG sensors were wrapped in epoxy resins and glass clothes, both installed during the segmental construction of casing pipes. In situ tests indicate that the proposed sensing system and installation technique can survive the downhole driving process of casing pipes, withstand a harsh service environment, and remain intact with the casing pipes for compatible strain measurements. The relative error of the measured strains between the distributed and discrete sensors is less than 12%. The FBG sensors successfully measured the maximum horizontal principal stress with a relative error of 6.7% in comparison with a cross multipole array acoustic instrument.

  4. The influence of vibrations on surface roughness formed during precision boring

    Science.gov (United States)

    Korzeniewski, Dariusz; Znojkiewicz, Natalia

    2017-01-01

    In this paper, the analysis of vibrations on surface roughness generated during boring with the application of the conventional boring tool and one with the damper is presented. The experiments included the measurement of vibration accelerations carried out with the piezoelectric sensor, as well as the evaluation of surface roughness parameters after each machining pass. The obtained results reveal that in the investigated range, no stability loss was found. Furthermore, the growth of the rotational speed induces the increase of vibration level, as well as the growth of the differences between the vibration values generated during boring with the conventional tool and one equipped with damper. Vibrations have also the direct influence on the machined surface roughness. In case of the tool equipped with the damper, the tool's overhang L had more intense influence than rotational speed n. However, for the conventional boring tool this dependency was unequivocal.

  5. A bayesian nework based risk model for volume loss in soft soils in mechanized bored tunnels

    NARCIS (Netherlands)

    Chivatá Cárdenas, Ibsen; Al-Jibouri, Saad H.S.; Halman, Johannes I.M.

    2012-01-01

    Volume loss is one of the most important risks when boring a tunnel. This is particularly true when a tunnel is being constructed in soft soils. The risk of excessive volume loss, if materialised can lead to large consequences such as damage in buildings on the surface. This paper describes the

  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. Superconducting Super Collider Laboratory : tunnel boring

    CERN Multimedia

    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.

  8. The Bored Self in Knowledge Work

    DEFF Research Database (Denmark)

    Costas, Jana; Kärreman, Dan

    2016-01-01

    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...

  9. 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...

  10. 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.

  11. Biomechanics of substrate boring by fig wasps.

    Science.gov (United States)

    Kundanati, Lakshminath; Gundiah, Namrata

    2014-06-01

    Female insects of diverse orders bore into substrates to deposit their eggs. Such insects must overcome several biomechanical challenges to successfully oviposit, which include the selection of suitable substrates through which the ovipositor can penetrate without itself fracturing. In many cases, the insect may also need to steer and manipulate the ovipositor within the substrate to deliver eggs at desired locations before rapidly retracting her ovipositor to avoid predation. In the case of female parasitoid ichneumonid wasps, this process is repeated multiple times during her lifetime, thus testing the ability of the ovipositioning apparatus to endure fracture and fatigue. What specific adaptations does the ovipositioning apparatus of a female ichneumonoid wasp possess to withstand these challenges? We addressed this question using a model system composed of parasitoid and pollinator fig wasps. First, we show that parasitoid ovipositor tips have teeth-like structures, preferentially enriched with zinc, unlike the smooth morphology of pollinator ovipositors. We describe sensillae present on the parasitoid ovipositor tip that are likely to aid in the detection of chemical species and mechanical deformations and sample microenvironments within the substrate. Second, using atomic force microscopy, we show that parasitoid tip regions have a higher modulus compared with regions proximal to the abdomen in parasitoid and pollinator ovipositors. Finally, we use videography to film wasps during substrate boring and analyse buckling of the ovipositor to estimate the forces required for substrate boring. Together, these results allow us to describe the biomechanical principles underlying substrate boring in parasitoid ichneumonid wasps. Such studies may be useful for the biomimetic design of surgical tools and in the use of novel mechanisms to bore through hard substrates.

  12. Post-drilling analysis of underbalanced drilled wells in Hassi-Messaoud Field, Algeria : case studies

    Energy Technology Data Exchange (ETDEWEB)

    Salim, K. [Sonatrach Inc., Alger (Algeria); Osisanya, S.O. [Oklahoma Univ., Norman, OK (United States); Madi, Y. [Algerian Petroleum Inst. (Algeria)

    2004-07-01

    Underbalanced drilling (UBD) is often undertaken in fractured reservoirs, in depleted formations that are susceptible to well bore damage or mud loss, and in medium to hard rock with problematic drilling rates. UBD involves manipulating the bottom hole circulating pressure so that it will be less than the static reservoir pressure, allowing formation fluids to flow into the well. UBD has increased profits at several oil and gas drilling properties including the Hassi Messaoud Field in Algeria where Sonatrach conducted trials in depleted oil production zones to assess the operational feasibility and commercial benefits of UBD. The technique was found to prevent lost circulation and differential pipe sticking; improve penetration rates; provide real-time reservoir evaluation while drilling; eliminate well stimulation costs; and, improve well bore productivity as a result of reduced formation damage. UBD also provides access to reserves that would otherwise not be produced, and substantially reduces total drilling and completion costs. 3 refs., 4 tabs., 9 figs.

  13. Reliability-Based Design and Quality Control of Bored Piles

    NARCIS (Netherlands)

    Bach, D.

    2014-01-01

    Bored piles are a type of deep foundations which have been and are being widely used in construction engineering such as high-rise buildings, bridges, jetties, and so on. Although bored piles have remarkable advantages over driven piles, the quality of bored piles is frequently affected by many caus

  14. Reliability-Based Design and Quality Control of Bored Piles

    NARCIS (Netherlands)

    Bach, D.

    2014-01-01

    Bored piles are a type of deep foundations which have been and are being widely used in construction engineering such as high-rise buildings, bridges, jetties, and so on. Although bored piles have remarkable advantages over driven piles, the quality of bored piles is frequently affected by many

  15. Energy and material efficient non-circular bore Bitter magnets

    CERN Document Server

    Akhmeteli, A

    2015-01-01

    There exist a number of experiments/applications where the second dimension of the bore of Bitter magnets is not fully utilized. Using an analytical solution for elliptical bore coils, we show that reducing one of the dimensions of the bore can lead to considerable decrease in consumed power and/or coil material.

  16. Tidal Bore detection in the Garonne River using high frequency GNSS data

    Science.gov (United States)

    Frappart, Frédéric; Roussel, Nicolas; Darrozes, José; Bonneton, Philippe; Bonneton, Natalie; Detandt, Guillaume; Perosanz, Felix; Loyer, Sylvain

    2016-04-01

    A tidal bore is a positive surge propagating upstream that may form when a rising tide with significant amplitude enters shallow, gently sloping and narrowing rivers. Tidal bores have a significant impact on the river ecosystem behavior, especially in terms of sediment transport. Most of the existing field studies were limited to visual observations. Only a few field experiments have been devoted to a quantitative study of the tidal bore dynamics. We carried out a field study in August, 2015, using a GNSS buoy to measure the tidal bore in the Garonne River (France) at Podensac located 140 km upstream of the estuary mouth. Precise Point Positioning and Differential GNSS techniques were used to determine the river surface height variations with a 20 Hz sampling rate. This site was selected owing to the presence of well-developed undular tidal bores and also because of the absence of any significant curvature of the river at this location, which limits the complexity of the tidal bore structure. The Gironde estuary is located in the Bay of Biscay, on the southwest coast of France, and is formed from the meeting of the rivers Dordogne and Garonne. In the Gironde mouth, the mean neap tidal range and mean spring tidal range is 2.5 m and 5 m, respectively. As the tide propagates upstream a marked ebbflood asymmetry occurs in the upper reaches of the estuary and the wave is amplified. This large amplitude tidal wave propagates in the Garonne and Dordogne rivers up to 160 km from the estuary mouth. Both GNSS buoy and reference station use a Leica AR10 antenna and GR25 receiver. Both stations (reference and buoy) acquired data with a 20 Hz sampling rate. GNSS data were processed using RTKLib. Results allowed to detect the the wave train of the tidal bore that caused an elevation of the surface of around 1.5 m. Comparisons were performed using acoustic data showing a good agreement between both sources of data.

  17. 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.

  18. 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.

  19. 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.

  20. Development of large bore superconducting magnet for wastewater treatment application

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hui Ming; Xu, Dong; Shen, Fuzhi; Zhang, Hengcheng; Li, Lafeng [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China)

    2017-03-15

    Water issue, especially water pollution, is a serious issue of 21st century. Being an significant technique for securing water resources, superconducting magnetic separation wastewater system was indispensable. A large bore conduction-cooled magnet was custom-tailored for wastewater treatment. The superconducting magnet has been designed, fabricated and tested. The superconducting magnet was composed of NbTi solenoid coils with an effective horizontal warm bore of 400 mm and a maximum central field of 2.56T. The superconducting magnet system was cooled by a two-stage 1.5W 4K GM cryocooler. The NbTi solenoid coils were wound around an aluminum former that is thermally connected to the second stage cold head of the cryocooler through a conductive copper link. The temperature distribution along the conductive link was measured during the cool-down process as well as at steady state. The magnet was cooled down to 4.8K in approximately 65 hours. The test of the magnetic field and quench analysis has been performed to verify the safe operation for the magnet system. Experimental results show that the superconducting magnet reached the designed magnetic performance.

  1. 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.

  2. 埕岛油田东营组低伤害入井液研究%Low Damage Well Liquid Estimation for Dongying Formation of Chengdao Oil Field

    Institute of Scientific and Technical Information of China (English)

    张金秋

    2013-01-01

    Dongying formation of Chengdao oil field lies in the onshore low permeability blocks .Reservoir damage is serious in the process of development over the years .A series of laboratory tests show that the potential reservoir damage factors are the water damage caused by wa-ter locks and Jamin action and the water sensitivity damage caused by clay mineral swelling .According to the different damages ,we have determined the additive type of the well liquid and optimized the additives to get a kind of low damage well liquid .This well liquid could control the integrated damage rate at about 10% and its oil reservoir protection effect is obvious.%埕岛油田东营组属于海上低渗透区块,在多年以来的作业过程中,储层伤害严重。通过一系列的室内试验,找出该储层潜在伤害因素主要为水锁和贾敏效应引起的水伤害,其次为粘土矿物膨胀引起的水敏伤害。针对不同的伤害因素,确定了作业入井液中的添加剂种类,并对添加剂进行优选,得到一种低伤害入井液。此作业入井液可将综合伤害率控制在10%左右,油层保护效果非常明显。

  3. 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.

  4. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence J. Pekot

    2004-06-30

    Two gas storage fields were studied for this project. Overisel field, operated by Consumer's Energy, is located near the town of Holland, Michigan. Huntsman Storage Unit, operated by Kinder Morgan, is located in Cheyenne County, Nebraska near the town of Sidney. Wells in both fields experienced declining performance over several years of their annual injection/production cycle. In both fields, the presence of hydrocarbons, organic materials or production chemicals was suspected as the cause of progressive formation damage leading to the performance decline. Core specimens and several material samples were collected from these two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  5. 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...

  6. 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

  7. 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.

  8. 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.

  9. Size segregation in a granular bore

    Science.gov (United States)

    Edwards, A. N.; Vriend, N. M.

    2016-10-01

    We investigate the effect of particle-size segregation in an upslope propagating granular bore. A bidisperse mixture of particles, initially normally graded, flows down an inclined chute and impacts with a closed end. This impact causes the formation of a shock in flow thickness, known as a granular bore, to travel upslope, leaving behind a thick deposit. This deposit imprints the local segregated state featuring both pure and mixed regions of particles as a function of downstream position. The particle-size distribution through the depth is characterized by a thin purely small-particle layer at the base, a significant linear transition region, and a thick constant mixed-particle layer below the surface, in contrast to previously observed S-shaped steady-state concentration profiles. The experimental observations agree with recent progress that upward and downward segregation of large and small particles respectively is asymmetric. We incorporate the three-layer, experimentally observed, size-distribution profile into a depth-averaged segregation model to modify it accordingly. Numerical solutions of this model are able to match our experimental results and therefore motivate the use of a more general particle-size distribution profile.

  10. 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

  11. 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.

  12. 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...

  13. 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.

  14. Determination of the geothermal well damage from its production tests; Determinacion del dano en pozos geotermicos a partir de sus pruebas de produccion

    Energy Technology Data Exchange (ETDEWEB)

    Aragon Aguilar, Alfonso; Izquierdo Montalvo, Georgina; Arellano Gomez, Victor [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2011-06-13

    In this work the evolution is described that undergoes the factor of damage in a well during its productive stage, which is identifiable from the diminution in the characteristics of its production. It is mentioned that during the productive stage of wells, its declination is, in many occasions, synonymous of the damage presence. Traditionally, the damage effect is determined from the equations for analysis of the transitory tests of pressure. Nevertheless, the execution of this type of tests requires relatively long periods of time to obtain the stabilization of the well and of significant costs. By the previous facts the development of techniques to determine the damage from production tests was initiated. In this article is presented the curve-type of geothermal inflow affected by the damage, from which the value of this one in a geothermal well for the time in which its test of production is realized can be determined. A methodology is proposed to determine the damage effect in the well using the proposed curve-type and its applicability with examples of test measurements of well discharge is demonstrated in Mexican geothermal fields. From the conducted analyses it is found that the numerical value of the damage determined in selected wells increases based on the time of exploitation, which indicates a deterioration of its productive characteristics. The previous statements aid to constitute a technical endorsement for the decision making, on the pertinent actions that can be executed in the well. [Spanish] En este trabajo se describe la evolucion que sufre el factor de dano en un pozo durante su etapa productiva, el cual es identificable a partir de la disminucion en las caracteristicas de su produccion. Se menciona que durante la etapa productiva de los pozos, su declinacion es, en muchas ocasiones, sinonimo de la presencia de dano. Tradicionalmente, el efecto de dano se determina a partir de las ecuaciones para analisis de las pruebas transitorias de presion

  15. 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.

  16. 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.

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

    OpenAIRE

    Zhang Huang; Shen Xingquan; Li Yaoming; Yang Fuhe; Kwon Paul

    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...

  18. 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.

  19. A new method for the determination of geophysical parameters by radon concentration measurements in bore-hole.

    Science.gov (United States)

    Papp, B; Deák, F; Horváth, A; Kiss, A; Rajnai, G; Szabó, Cs

    2008-11-01

    We propose a new method to measure the (222)Rn concentration in a closed bore-hole and to use the results for estimation of the diffusion parameter and the average radium content of the surrounding geological formations. In a closed bore-hole, only several meters from the surface, the radon concentration is rather constant (in the +/-15% range) under different meteorological conditions. The inflow of radon gas, after removing the radon from the bore-hole by dry nitrogen, shows characteristic time-dependence, which is determined by the diffusion parameter for radon in the surrounding environment. The experimental data were well described by a straightforward model calculation. From the results estimate can be given for the diffusion parameter and for the average radium content of the surrounding geological formation.

  20. 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.

  1. Effect of sulphurous mineral water in haematological and biochemical markers of muscle damage after an endurance exercise in well-trained athletes.

    Science.gov (United States)

    Soria, Marisol; González-Haro, Carlos; Esteva, Santiago; Escanero, Jesús F; Pina, José R

    2014-01-01

    To investigate the effects of sulphurous mineral water (SMW) after a hydroponic treatment on muscle damage, antioxidant activity and peripheral blood changes induced by submaximal exercise. Thirty well-trained male triathletes were supplemented with SMW or placebo: 3 weeks of placebo, 30 days of wash out and 3 weeks of SMW. After both periods, participants ran for 2 h at 70% maximal aerobic speed. Antioxidant enzymes, lipid peroxidation, antioxidant capacity and blood cell markers were compared between placebo and SMW at pre-exercise (T0), immediately post-exercise (T1), 24 h post-exercise (T2) and 48 h post-exercise (T3). Total thiols decreased until T3 vs. T0 for both placebo and SMW; transient red blood cells, haemoglobin and haematocrit increased were shown at T1 vs. T0 and for leucocytes until T2 vs. T0, only for placebo group. Total thiols increased significantly in SMW vs. placebo at T0; Thiobarbituric acid reactive species was significantly higher at T0, T1, T2 and T3; catalase increased significantly at T1; creatine phosphokinase decreased significantly at T1, T2 and T3, although no significant differences were found at T0. Furthermore, red blood cells, haemoglobin and haematocrit were significantly higher and leucocytes were significantly lower at T0 and T1 in SMW group vs. placebo group. This study suggests that three weeks of SMW supplementation may protect from exercise-induced muscle damage.

  2. Wide, short bore magnetic resonance at 1.5 t: reducing the failure rate in claustrophobic patients.

    Science.gov (United States)

    Hunt, C H; Wood, C P; Lane, J I; Bolster, B D; Bernstein, M A; Witte, R J

    2011-09-01

    Claustrophobic reactions in patients undergoing magnetic resonance imaging (MRI) have a significant impact on the workflow, patient acceptance and ultimately the costs involved in obtaining a diagnostic scan. The purpose of this study was to determine if the use of a wide, short bore MRI scanner could reduce the need for general anesthesia assistance in these cases. Between September 2006 and March 2008, all patients for whom MRI examinations of the head and/or spine were canceled or prematurely terminated due to claustrophobia on a standard 60 cm bore, 1.5 T scanner were scheduled to be re-scanned on a 70 cm wide bore, 1.25 m long 1.5 T scanner. This re-scanning attempt was made 2 or more days prior to a scheduled anesthesia-assisted MRI appointment. If the patient successfully completed the wide bore MRI examination then the anesthesia-assisted MRI appointment was canceled. A total of 56 patients were included in this study. The examinations included individual body regions as well as combination examinations (head and cervical spine, entire spine etc.). A total of 72 body regions were examined in 56 patients. Of these regions, 65 (90%) were completed successfully, 50 patients (89%) successfully completed a diagnostic examination on the 70 cm scanner and 6 patients (11%), all of whom were scheduled for examinations which included the head, were unable to complete the examination on the wide bore scanner. A 1.5 T wide short bore scanner increases the examination success rate in patients with claustrophobia and substantially reduces the need for anesthesia-assisted MRI examinations even when claustrophobia is severe.

  3. 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?

  4. 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.

  5. Design of a 20 T, 200 mm bore resistive magnet

    Energy Technology Data Exchange (ETDEWEB)

    Gao, B.J.; Bird, M.D.; Bole, S.; Eyssa, Y.M.; Schneider-Muntau, H.J. [National High Magnetic Field Lab., Tallahassee, FL (United States)

    1996-07-01

    A 20 tesla, three coil, 200 mm bore, 20 MW resistive magnet is being designed at the National High Magnetic Field Laboratory in Tallahassee, FL., USA, in cooperation with the High Magnetic Field Laboratory of Grenoble, France. The outer two coils are axially-cooled and are connected electrically in series producing a central field of 11.27 T in a 365 mm warm bore while consuming 13.5 MW of power. The 6.5 MW inner coil (insert) is a poly-Bitter design with two sub-coils connected electrically in parallel and they together are connected in series to the two outer coils. The field of the inner coil is 8.78 T resulting in a 20 T total field in a 200 mm warm bore. All four coils are made of hard copper.

  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. Dimension effects in plasma immersion ion implantation of cylindrical bore

    CERN Document Server

    Tian Xiu Bo; Tong Hong Hui; Chu, P K

    2002-01-01

    Plasma immersion ion implantation is a new technique pertaining to ion implantation. Different from the case of exterior surface treatment, plasma immersion ion implantation of interior surface possesses dimension effects. Consequently it is a challenge to implant the inner wall of a cylindrical bore due to this finite dimension.The ion energy cannot be linearly changed with applied voltage and there exists a saturation value due to overlap effect of plasma sheath. The plasma in the bore may rapidly be depleted, which is attributed to finite plasma volume and plasma-sheath con-flowing effect. For instance the plasma depletion time is about 0.55 mu s when a bore with a diameter of 20 cm is treated under conditions of applied voltage of 30 kV and plasma density of 2 x 10 sup 1 sup 5 ions/cm sup 3. Interior plasma-source hardware may be an effective solution

  8. Physical Simulation for Large-Bore Copper Vapor Laser

    Institute of Scientific and Technical Information of China (English)

    YU De-Li; WANG Run-Wen; TAO Yong-Xiang

    2000-01-01

    On the basis of the electric circuit differential equations and the nonlinear partial differential equations of kinetics,a kinetic model for a series of large-bore copper-vapor lasers is carried out. Through the consistent computational results the radial kinetic parameters such as the stimulating electric field and the plasma electron temperature are presented. The factors, which evidently influence the output power and the beam quality of the large-bore copper-vapor laser, are the buffer gas pressure and the charging voltage.

  9. 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

  10. Boring of full scale deposition holes at the Aespoe Hard Rock Laboratory. Operational experiences including boring performance and a work time analysis

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Christer [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Johansson, Aasa [SWECO, Stockholm (Sweden)

    2002-12-01

    Thirteen experimental deposition holes similar to those in the present KBS-3 design have been bored at the Aespoe Hard Rock Laboratory, Oskarshamn, Sweden. The objective with the boring program was to test and demonstrate the current technique for boring of large vertical holes in granitic rock. Conclusions and results from this project is used in the planning process for the deposition holes that will be bored in the real repository for spent nuclear fuel. The boreholes are also important for three major projects. The Prototype Repository, the Canister Retrieval Test and the Demonstration project will all need full-scale deposition holes for their commissioning. The holes are bored in full scale and have a radius of 1.75 m and a depth of 8.5 m. To bore the holes an existing TBM design was modified to produce a novel type Shaft Boring Machine (SBM) suitable for boring 1.75 m diameter holes from a relatively small tunnel. The cutter head was equipped with two types of roller cutters: two row carbide button cutters and disc cutters. Removal of the cuttings was made with a vacuum suction system. The boring was monitored and boring parameters recorded by a computerised system for the evaluation of the boring performance. During boring of four of the holes temperature, stress and strain measurements were performed. Acoustic emission measurements were also performed during boring of these four holes. The results of these activities will not be discussed in this report since they are reported separately. Criteria regarding nominal borehole diameter, deviation of start and end centre point, surface roughness and performance of the machine were set up according to the KBS-3 design and were fulfilled with a fair margin. The average total time for boring one deposition hole during this project was 105 hours.

  11. 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.

  12. 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.

  13. 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

  14. High performance projectile seal development for non perfect railgun bores

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, T.R.; Vine, F.E. Le; Riedy, P.E.; Panlasigui, A. [Maxwell Labs., Inc., San Diego, CA (United States); Hawke, R.S.; Susoeff, A.R. [Lawrence Livermore National Lab., CA (United States)

    1997-01-01

    The sealing of high pressure gas behind an accelerating projectile has been developed over centuries of use in conventional guns and cannons. The principal concern was propulsion efficiency and trajectory accuracy and repeatability. The development of guns for use as high pressure equation-of-state (EOS) research tools, increased the importance of better seals to prevent gas leakage from interfering with the experimental targets. The development of plasma driven railguns has further increased the need for higher quality seals to prevent gas and plasma blow-by. This paper summarizes more than a decade of effort to meet these increased requirements. In small bore railguns, the first improvement was prompted by the need to contain the propulsive plasma behind the projectile to avoid the initiation of current conducting paths in front of the projectile. The second major requirements arose from the development of a railgun to serve as an EOS tool where it was necessary to maintain an evacuated region in front of the projectile throughout the acceleration process. More recently, the techniques developed for the small bore guns have been applied to large bore railguns and electro-thermal chemical guns in order to maximize their propulsion efficiency. Furthermore, large bore railguns are often less rigid and less straight than conventional homogeneous material guns. Hence, techniques to maintain seals in non perfect, non homogeneous material launchers have been developed and are included in this paper.

  15. Boring and Drilling Tools. Pre-Apprenticeship Phase 1 Training.

    Science.gov (United States)

    Lane Community Coll., Eugene, OR.

    This self-paced student training module on boring and drilling tools is one of a number of modules developed for Pre-apprenticeship Phase 1 Training. Purpose of the module is to enable students to identify, select, and understand the proper use of many common awls, bits, and drilling tools. The module may contain some or all of the following: a…

  16. 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.

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

    Institute of Scientific and Technical Information of China (English)

    王涛; 高天赋

    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. Direc-tions for future research are discussed.

  18. 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.

  19. 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.

  20. 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.

  1. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence J. Pekot; Ron Himes

    2004-05-31

    Core specimens and several material samples were collected from two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  2. Modeling Cryptosporidium and Giardia in Ground and Surface Water Sources in Rural India: Associations with Latrines, Livestock, Damaged Wells, and Rainfall Patterns.

    Science.gov (United States)

    Daniels, Miles E; Smith, Woutrina A; Schmidt, Wolf-Peter; Clasen, Thomas; Jenkins, Marion W

    2016-07-19

    Surface and groundwater contamination with fecal pathogens is a public health concern especially in low-income settings where these sources are used untreated. We modeled observed Cryptosporidium and Giardia contamination in community ponds (n = 94; 79% contaminated), deep tubewells (DTWs) (n = 107; 17%), and shallow tubewells (STWs) (n = 96; 19%) during the 2012 and 2013 monsoon seasons (June-August) in 60 villages in Puri District, India to understand sources and processes of contamination. Detection of Cryptosporidium and/or Giardia in a tubewell was positively associated with damage to the well pad for DTWs, the amount of human loading into pour-flush latrine pits nearby (≤15 m) for STWs, and the village literacy rate (for Giardia in STWs). Pond concentration levels were positively associated with the number of people practicing open defecation within 50 m and the sheep population for Cryptosporidium, and with the village illiteracy rate for Giardia. Recent rainfall increased the risk of Cryptosporidium in STWs (an extreme event) and ponds (any), while increasing seasonal rainfall decreased the risk of Giardia in STWs and ponds. Full latrine coverage in this setting is expected to marginally reduce pond Cryptosporidium contamination (16%) while increasing local groundwater protozoal contamination (87-306%), with the largest increases predicted for Cryptosporidium in STWs.

  3. Status of organochlorine pesticides in the drinking water well-field located in the Delhi region of the flood plains of river Yamuna

    Directory of Open Access Journals (Sweden)

    P. K. Mutiyar

    2011-08-01

    Full Text Available This study presents the occurrence of pesticides in a well-field located in Yamuna flood plain of Delhi region. Ground water sampling campaigns were carried out during pre-monsoon and post-monsoon periods covering 21 bore-wells and 5 Ranney wells. Major 17 organochlorine pesticides (OCP's along with other water quality parameters were monitored during this period. Pesticide concentrations were determined using GC- ECD, while GC-MS was used for confirmatory purposes. OCP's groups like ∑HCH, ∑DDT, endosulfan and aldrin were observed in this well-field. Concentration of OCPs from Ranney wells exceeded the limit (1 μg l−1 prescribed by the Bureau of Indian Standards (BIS in pre-monsoon season, though OCP levels in bore wells were within BIS limits. However, these levels were very close to the World Health Organisation (WHO and European Union (EU limit of for pesticides (0.5 μg l−1 in many samples. Bore well produced better quality water compared to the water from Ranney wells. Although, the level of OCP's was slightly lower than prescribed limit of national regulatory agency but such low doses may cause long-term damage to human populations if such water is consumed for longer durations. At low doses OCP's acts as endocrine disrupting agent and cause metabolic disorders in local population.

  4. 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.

  5. The distribution of worm borings in brachiopod shells from the Caradoc Oil Shale of Estonia.

    OpenAIRE

    Vinn, Olev

    2005-01-01

    International audience; Abundant worm borings were found in some brachiopod shells (Clitambonites, Estlandia, Nicolella) from the Ordovician (Caradoc) oil shale in North Estonia. 9 of 21 brachiopod genera (43 %) have been bored. Excluding the size and thickness of valves, no common morphological feature discriminates the brachiopods with borings from those without them. The Trypanites are host-specific, and the frequency of bored valves varies from 6.5 % in Bekkerina to 51 % in Estlandia. The...

  6. 30 CFR 18.22 - Boring-type machines equipped for auxiliary face ventilation.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boring-type machines equipped for auxiliary... AND ACCESSORIES Construction and Design Requirements § 18.22 Boring-type machines equipped for auxiliary face ventilation. Each boring-type continuous-mining machine that is submitted for approval...

  7. 46 CFR 148.04-13 - Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ferrous metal borings, shavings, turnings, or cuttings... Requirements for Certain Material § 148.04-13 Ferrous metal borings, shavings, turnings, or cuttings (excluding... described as ferrous metal borings, shavings, turnings, or cuttings on board vessels (excluding stainless...

  8. Nanoscale effects on the thermal and mechanical properties of AlGaAs/GaAs quantum well laser diodes: influence on the catastrophic optical damage

    Science.gov (United States)

    Souto, Jorge; Pura, José Luis; Jiménez, Juan

    2017-06-01

    In this work we study the catastrophic optical damage (COD) of graded-index separate confinement heterostructure quantum well (QW) laser diodes based on AlGaAs/GaAs. The emphasis is placed on the impact that the nanoscale physical properties have on the operation and degradation of the active layers of these devices. When these laser diodes run in continuous-wave mode with high internal optical power densities, the QW and guide layers can experiment very intense local heating phenomena that lead to device failure. A thermo-mechanical model has been set up to study the mechanism of degradation. This model has been solved by applying finite element methods. A variety of physical factors related to the materials properties, which play a paramount role in the laser degradation process, have been considered. Among these, the reduced thicknesses of the QW and the guides lead to thermal conductivities smaller than the bulk figures, which are further reduced as extended defects develop in these layers. This results in a progressively deteriorating thermal management in the device. To the best of our knowledge, this model for laser diodes is the first one to have taken into account low scale mechanical effects that result in enhanced strengths in the structural layers. Moreover, the consequences of these conflicting size-dependent properties on the thermo-mechanical behaviour on the route to COD are examined. Subsequently, this approach opens the possibility of taking advantage of these properties in order to design robust diode lasers (or other types of power devices) in a controlled manner.

  9. Numerical model for surge and swab pressures on wells with cross-section variation

    Energy Technology Data Exchange (ETDEWEB)

    Fedevjcyk, Joao Victor; Junqueira, Silvio Luiz de Mello; Negrao, Cezar Otaviano Ribeiro [UTFPR - Federal University of Technology - Parana - Curitiba, PR (Brazil)], e-mails: silvio@utfpr.edu.br, negrao@utfpr.edu.br

    2010-07-01

    Drilling is one of the most complex steps in petroleum exploration. The process is accomplished by rotating a drill bit to compress the rock formation. During drilling, a fluid is pumped into the well to lubricate and cool down the drill bit, to clean up the well, to avoid the formation fluid influx to the well and also to stabilize the borehole walls. Fluid circulation, however, can be interrupted for maintenance reasons and the drill pipe can be moved to remove the drill bit. The downward or upward movement of the drill pipe displaces the fluid within the well causing either under pressure (swab) or over pressure (surge), respectively. If the pressure at the well bore overcomes the formation fracture pressure, a loss of circulation can take place. On the other way round, the upward movement may reduce the pressure below the pore pressure and an inflow of fluid to the well (kick) can occur. An uncontrolled kick may cause a blowout with serious damages. The transient flow induced by the axial movement of the drill pipe is responsible for the pressure changes at the well bore. Nevertheless, the well bore cross section variation may modify the pressure change within the pipe. In this paper, the effects of diameter variation of the drilling well on the surge and swab pressures are investigated. The equations that represent the phenomenon (mass and momentum conservation) are discretized by the finite volume method. Despite its non-Newtonian properties, the fluid is considered Newtonian in this first work. The drill pipe is considered closed and the flow is assumed as single-phased, one-dimensional, isothermal, laminar, compressible and transient. A sensitivity analysis of the flow parameters is carried out. The cross-section changes cause the reflection of the pressure wave, and consequently pressure oscillations. (author)

  10. Performance model for Micro Tunnelling Boring Machines (MTBM

    Directory of Open Access Journals (Sweden)

    J. Gallo

    2017-06-01

    Full Text Available From the last decades of the XX century, various formulae have been proposed to estimate the performance in tunnelling of disc cutters, mainly employed in Tunnelling Boring Machines (TBM. Nevertheless, their suitability has not been verified in Micro Tunnelling Boring Machines (MTBM, with smaller diameter of excavation, between 1,000 and 2,500 mm and smaller cutter tools, where parameters like joint spacing may have a different influence. This paper analyzes those models proposed for TBM. After having observed very low correlation with data obtained in 15 microtunnels, a new performance model is developed, adapted to the geomechanical data available in this type of works. Moreover, a method to calculate the total amount of hours that are necessary to carry out microtunnels, including all the tasks of the excavation cycle and installation and uninstallation.

  11. Study on influence of ground settlement in bored metro tunnel

    Institute of Scientific and Technical Information of China (English)

    FANG Jiang-hua; ZHANG Zhi-hong

    2006-01-01

    At present the bored construction method is one of the main construction methods of metro and tunnel construction in China. The empirical estimated formulas of tunnel ground surface settlement using the bored construction method were obtained,combining the mechanical stimulant calculated result of tunnel model of different embedded depth, different cross section and different construction method and the actual measurement data of Beijing metro construction. According to the regressed analysis of calculated data, the calculated equations of ground surface settlement value and settlement range of tunnel section under the condition of different embedded depth, different cross section and different construction method were gained. Among them there are some empirical formulas can apply to the construction design ofmetro tunnel directly.

  12. 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.

  13. 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.

  14. Bore-hole survey at Camp Century, 1989

    DEFF Research Database (Denmark)

    Dahl-Jensen, Dorthe; Gundestrup, NS.; Hansen, BL.

    1993-01-01

    A combination of the directional surveys of the Camp Century borehole from 1966, 1967, 1969 and 1989 has revealed a deformation pattern similar to that measured at Dye-3, South Greenland and Byrd Station, Antarctica showing high deformation rate for Wisconsin ice. Compared to the Dye-3 profile, t......, the deformation shows the same pattern even in details. The surface velocity obtained by integrating the bore hole deformation is in agreement with that obtained from satellite measurements Udgivelsesdato: jan...

  15. 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.

  16. Ethylene glycol as bore fluid for hollow fiber membrane preparation

    KAUST Repository

    Le, Ngoc Lieu

    2017-03-31

    We proposed the use of ethylene glycol and its mixture with water as bore fluid for the preparation of poly(ether imide) (PEI) hollow fiber membranes and compared their performance and morphology with membranes obtained with conventional coagulants (water and its mixture with the solvent N-methylpyrrolidone (NMP)). Thermodynamics and kinetics of the systems were investigated. Water and 1:1 water:EG mixtures lead to fast precipitation rates. Slow precipitation is observed for both pure EG and 9:1 NMP:water mixture, but the reasons for that are different. While low osmotic driving force leads to slow NMP and water transport when NMP:water is used, the high EG viscosity is the reason for the slow phase separation when EG is the bore fluid. The NMP:water mixture produces fibers with mixed sponge-like and finger-like structure with large pores in the inner and outer layers; and hence leading to a high water permeance and a high MWCO suitable for separation of large-sized proteins. As compared to NMP:water, using EG as bore fluid provides fibers with a finger-like bilayered structure and sponge-like layers near the surfaces, and hence contributing to the higher water permeance. It also induces small pores for better protein rejection.

  17. 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.

  18. Numerical study of breakwater failure due to tsunami-like undular bore impacts: The case of the port of Soma.

    Science.gov (United States)

    Martin-Medina, Manuel; Morichon, Denis; Abadie, Stephane; Le Roy, Sylvestre; Lemoine, Anne

    2017-04-01

    The Tohoku tsunami, that impacted the Japanese coast in 2011, caused great damages on many offshore vertical breakwaters ranging from the erosion of the rubble mound to the partial displacement or total collapse of caissons. The breakwater failure mechanisms were function of the tsunami wave types that vary along the Japanese coast according to the bathymetry features. The Iwate coast, characterized by deep water depths and steep slopes, was mainly impacted by tsunami overflow leading in particular to the failure of the world's deepest breakwater of Kamaishi. In the shallow waters of the Sendai bay, observations showed that breakwaters protecting harbor entrances were impacted by short waves train resembling to undular bore. This work aims to investigate this latter type of tsunami wave impacts that are less reported in the literature. We chose to focus on the highly damaged offshore breakwater of Soma, located in the south part of the Sendai bay. The hydrodynamics conditions during the tsunami impact are investigated using the VARANS Thetis code (Desombre et al., 2012), which allows to simulate both the free surface flow and the flow inside the rubble mound simulated by a porous medium. The model is forced at the offshore boundaries by the Funwave Boussinesq code that describes the transformation of the tsunami waves from the source to the generation of undular bores in shallow waters. The study includes the computation of forces acting on the caissons. We discuss the relevance of describing the hydrodynamics at the short wave scale to assess breakwater stability in the course of tsunami-like undular bore impact. References Desombre, J., Morichon, D., & Mory, M. (2012). SIMULTANEOUS SURFACE AND SUBSURFACE AIR AND WATER FLOWS MODELLING IN THE SWASH ZONE. Coastal Engineering Proceedings, 1(33), 56.

  19. The Study of Relationships between the Damage of Visual Function and Hemorrheology, Ocular Rheography, as well as Other Related Factors in Patients with Primary Open Angle Glaucoma (POAG)

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    Researches of glaucoma visual function damage, hemorrheololgy, ocular rheography and other related multiplex factors, with computed multifactorial stepwise regresion analysis, indicate that the elevation of intraocular pressure (IOP) is not the only factor to induce visual impairment. POAG patients are shown to have markedly reduced diastolic purfussion pressure in ophthalmic artery, besides prolonged filling time of the retinal artery and vein, diminished erythrocyte deformability and increased platele...

  20. 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.

  1. 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.

  2. Analysis of Nonlinear Discrete Time Active Control System with Boring Chatter

    Directory of Open Access Journals (Sweden)

    Shujing Wu

    2014-03-01

    Full Text Available In this work we study the design and analysis for nonlinear discrete time active control system with boring charter. It is shown that most analysis result for continuous time nonlinear system can be extended to the discrete time case. In previous studies, a method of nonlinear Model Following Control System (MFCS was proposed by Okubo (1985. In this study, the method of nonlinear MFCS will be extended to nonlinear discrete time system with boring charter. Nonlinear systems which are dealt in this study have the property of norm constraints ║ƒ (v (k║&le&alpha+&betaβ║v (k║&gamma, where &alpha&ge0, &beta&ge0, 0&le&gamma&le1. When 0&le&gamma&le1. It is easy to extend the method to discrete time systems. But in the case &gamma = 1 discrete time systems, the proof becomes difficult. In this case, a new criterion is proposed to ensure that internal states are stable. We expect that this method will provide a useful tool in areas related to stability analysis and design for nonlinear discrete time systems as well.

  3. Report on the development of the large-bore powder gun for the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    B.J. Jensen

    2009-03-01

    Experiments are needed to locate phase boundaries and to provide both Hugoniot data and off-Hugoniot data (such as principle isentrope, refreezing, dynamic strength, etc.) achieved through complex loading paths. The objective of the current work was to de- velop a large bore (3.5 inch or greater) powder gun capable of accelerating projectiles to moderately high velocities exceeding 2 km/s for impact experiments. A total of 24 ex- periments were performed to measure the projectile velocity, breech strain, and projectile tilt to demonstrate the performance of the gun up to the maximum breech capacity of 16 pounds of propellant. Physics experiments using a multislug method were performed to obtain sound speed and Hugoniot for shocked cerium metal and to demonstrate the ability of the large bore gun to conduct well-defined, plate-impact experiments. In addition, six experiments were performed on the prototype containment system to examine the ability of the launcher and containment system to withstand the impact event and contain the propellant gases and impact debris postshot. The data presented here were essential for qualification of the launcher for experiments to be conducted at the U1a complex of the Nevada Test Site.

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

    DEFF Research Database (Denmark)

    Borden, Zac; Koblitz, Tilman; Meiburg, Eckart

    2012-01-01

    Bores, or hydraulic jumps, appear in many natural settings and are useful in many industrial applications. If the densities of the two fluids between which a bore propagates are very different (i.e., water and air), the less dense fluid can be neglected when modeling a bore analytically-a single......-layer hydraulic model will accurately predict a bore's speed of propagation. A two-layer model is required, however, if the densities are more similar. Mass is conserved separately in each layer and momentum is conserved globally, but the model requires for closure an assumption about the loss of energy across...... a bore. In the Boussinesq limit, it is known that there is a decrease of the total energy flux across a bore, but in the expanding layer, turbulent mixing at the interface entrains high speed fluid from the contracting layer, resulting in an increase in the flux of kinetic energy across the expanding...

  5. Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials

    Science.gov (United States)

    2015-05-01

    Technical Report ARWSB-TR-15003 Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials Mark E. Todaro...SUBTITLE Customer Overview of Pulsed Laser Heating for Evaluation of Gun Bore Materials 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...thermomechanical effects that occur at the bore of large and medium caliber guns during firing. Hence, PLH has been used not only to gain insight into the erosion

  6. Gravity Flow in Proposed Enteral Tube Small-Bore Connectors.

    Science.gov (United States)

    Hurt, Ryan T; Epp, Lisa M; Pattinson, Adele K; Duellman, Wanda M; Corner, Stephen M; Mundi, Manpreet S

    2017-04-01

    Enteral nutrition (EN) misconnections have been identified as a serious and potential deadly problem. An international effort led by EN industry leaders has developed a small-bore enteral connector (ENFit) that in theory will reduce the frequency of misconnections. Despite the potential benefit of preventing misconnections, the full impact of adoption of the ENFit connector is unknown. To assess the impact of transitioning to ENFit on our home EN (HEN) patients, the current study evaluated gravity feeding comparing 2 proposed small-bore connectors to the legacy (current connector) using various commercial formulas. Six commonly used enteral formulas in our facility with varying density and viscosity were tested in triplicate. Forty milliliters of formula was poured into a syringe connected to an ENFit or legacy (current) feeding connector attached to varying French size tubes. The time it took formula to flow through the connectors was recorded, and the test was repeated in triplicate. All formulas took significantly longer to flow through the first ENFit connector compared with the legacy connector ( P gravity flow, as ENFit tubes are being developed and adopted.

  7. 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.

  8. 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

  9. 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

  10. Fiscal year 1995 well plugging and abandonment program Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This report is a synopsis of the progress of the well plugging and abandonment program at the Y-12 Plant, Oak Ridge, Tennessee, from September 1994 through August 1995. A total of 67 wells, piezometers, and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned if (1) its construction did not meet current standards (substandard construction); (2) it was irreparably damaged or had deteriorated beyond practical repair; (3) its location interfered with or otherwise impeded site operations, construction, or closure activities; or (4) special circumstances existed as defined on a case-by-case basis and approved by the Y-12 Plant Groundwater Protection Program (GWPP) Manager. This summary report contains: general geologic setting of the Y-12 Plant and vicinity; discussion of well plugging and abandonment methods, grouting procedures, and waste management practices (a Waste Management Plan for Drilling Activities is included in Appendix C); summaries of plugging and abandonment activities at each site; and quality assurance/quality control (QA/QC) and health and safety protocols used during the FY 1995 Plugging and Abandonment Program.

  11. 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.

  12. 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...

  13. 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.

  14. A foam formulation of an entomopathogenic fungus 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...

  15. 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

  16. 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

  17. Persistence motives in irrational decisions to complete a boring task.

    Science.gov (United States)

    Halkjelsvik, Torleif; Rise, Jostein

    2015-01-01

    We explored a novel task paradigm where participants from the online work marketplace Amazon Mechanical Turk were given the choice to quit or continue an unfinished boring task for identical economic rewards. In Studies 1a and 1b, about half the participants chose to continue (corresponding to an average of 55 and 35 cents in foregone earnings). Participants' self-reported reasons for continuing involved various types of persistence motives, reflecting a desire to persist or complete per se. Studies 2, 3a, 3b, and 3c ruled out the possibility that people continued because they enjoyed the task or believed there were additional rewards for continuing. Study 4 showed that the choice to quit/continue was associated with the manner in which the choice was presented (persistence test vs. decision-making test) and individual differences in dispositional persistence motives. The present data indicate that motivational forces independent of the focal reward may affect intertemporal decisions.

  18. 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.

  19. 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.

  20. A tunnel boring system for the Yucca Mountain Project

    Energy Technology Data Exchange (ETDEWEB)

    Short, S.N. [Construction & Tunneling Services, Inc., Kent, WA (United States)

    1994-12-31

    Design of the Yucca Mountain Project (YMP) tunnel boring machine (TBM) and backup began in June of 1993, with fabrication, machining and light assembly proceeding through to the end of the year. The original specifications for the project were contained in the request for quote for the YMP TBM and in Construction & Tunneling Services proposal document. As with all complex custom assignments, much of the finer details of the definition of the final scope of delivery was concurrent with the design effort itself. The summation of this effort is described in this paper. The major technical scope of the machine delivery is defined by the parameters listed in TABLE 1. Within the confines of the installed power and design excavation rates, the final product has been tailored to suit the particular needs of the project.

  1. UVA activation of N-dialkylnitrosamines releasing nitric oxide, producing strand breaks as well as oxidative damages in DNA, and inducing mutations in the Ames test

    Energy Technology Data Exchange (ETDEWEB)

    Arimoto-Kobayashi, Sakae, E-mail: arimoto@cc.okayama-u.ac.jp [Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima, Okayama 700-8530 (Japan); Sano, Kayoko; Machida, Masaki; Kaji, Keiko; Yakushi, Keiko [Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima, Okayama 700-8530 (Japan)

    2010-09-10

    alkylative DNA damages and mutation.

  2. 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.

  3. 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

  4. Fiscal Year 1993 Well Plugging and Abandonment Program Summary Report Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    This report is a synopsis of the progress of the well plugging and abandonment program at the Y-12 Plant, Oak Ridge, Tennessee, from October 1993 through August 1994. A total of 57 wells and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the U.S. Department of Energy, Y-12 Plant, Oak Ridge, Tennessee.

  5. Fiscal year 1993 well plugging and abandonment program, Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This report is a synopsis of the progress of the well plugging and abandonment program at the Y-12 Plant, Oak Ridge, Tennessee, from December 1992 through August 20, 1993. A total of 70 wells and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the US Department of Energy, Y-12 Plant, Oak Ridge, Tennessee (HSW, Inc. 1991).

  6. 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

  7. 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.

  8. Problems in the wellbore integrity of a shale gas horizontal well and corresponding countermeasures

    Directory of Open Access Journals (Sweden)

    Zhonglan Tian

    2015-12-01

    Full Text Available In the Changning–Weiyuan national shale gas demonstration area, SW Sichuan Basin, the wellbore integrity damage occurs in some shale gas wells and has direct effect on the gas production rate of single shale gas horizontal well. After statistics analysis was performed on the problems related with wellbore integrity, such as casing damage, casing running difficulty and cement sheath blow-by, the multi-factor coupling casing stress calculation and evaluation mode laws established. Then study was conducted on the influential mechanism of multi-factor coupling (temperature effect, casing bending and axial pressure on casing damage. The shale slip mechanism and its relationship with casing sheared formation were analyzed by using the Mohr–Coulomb criterion. Inversion analysis was performed on the main controlling factors of casing friction by using the developed casing hook load prediction and friction analysis software. And finally, based on the characteristics of shale gas horizontal wells, wellbore integrity control measures were proposed in terms of design and construction process, so as to improve the drilling quality (DQ. More specifically, shale gas well casing design calculation method and check standard were modified, well structure and full bore hole trajectory design were optimized, drilling quality was improved, cement properties were optimized and cement sealing integrity during fracturing process was checked. These research findings are significant in the design and management of future shale gas borehole integrity.

  9. Application of Raise Boring Machine to Construction of Muruo Hydropower Station%反井钻机在沐若水电站施工中的应用

    Institute of Scientific and Technical Information of China (English)

    桂良玉

    2014-01-01

    In the water diversion system project of Muruo Hydropower Station in Malaysia ,there were two vertical shafts with a depth of 163.13m and 159.55m individually and a raise boring project of two pressure regulation shafts with a depth of 73.15m and 73.26m individually.A BMC300 mode raise boring machine was applied to the constructions with high accuracy ,good safety ,rapid construction speed and expected effect. The successful implementation of the raise boring project opened a door to the world of the international hydropower technology for China raise boring technology and increased the influences of China raise boring technology in the world as well as provided the overseas experi-ences.%__摘_马来西亚沐若水电站引水系统工程中的2个深度分别为163.13和159.55m的立井,以及2个深度分别为73.15和73.26m的调压井反井工程,采用BMC300型反井钻机施工,精确度高,安全性好,施工速度快,收到了预期效果。该项目的成功实施,为我国反井钻井技术走出国门,面向世界水电技术领域,扩大影响,提供了经验。

  10. Tidal bores, turbulence and mixing above deep-ocean slopes

    Science.gov (United States)

    Winters, Kraig

    2016-11-01

    A tidally driven, stably-stratified turbulent boundary layer over supercritically sloping topography is simulated numerically using a spectral LES approach (Winters, 2015, 2016). The near boundary flow is characterized by quasi-periodic, bore-like motions, whose temporal signature is compared to the high-resolution ocean mooring data of van Haren (2006). The relatively thick bottom boundary layer remains stably stratified owing to the regular cycling of unmixed ambient fluid into the turbulent boundary layer and episodic expulsion events where fluid is ejected into the stratified interior. The effective diffusivity of the flow near the boundary is estimated by means of a synthetic dye tracer experiment. The average dissipation rate within the dye cloud is computed and combined with the diffusivity estimate to yield an overall mixing efficiency of 0.15. Both the estimated diffusivity and dissipation rates are in reasonable agreement with the microstructure observations of Kunze et al. (2012) when scaled to the environmental conditions at the Monterey and Soquel Canyons and to the values estimated by van Haren and Gostiaux (2012) above the sloping bottom of the Great Meteor Seamount in the Canary Basin.

  11. On construction scheme of bored piles%谈灌注桩施工方案

    Institute of Scientific and Technical Information of China (English)

    刘立创

    2012-01-01

    The paper points out the bored pile is the common foundation treatment,and fully introduces the craft procedure and craft methods of the bored pile construction by taking the engineering example of the bored pile construction,so as to enhance the application of the bored pile.%指出灌注桩是常用的一种地基处理方法,通过灌注桩施工的一个工程实例,较全面地介绍了灌注桩施工的工艺流程、工艺方法,从而促进灌注桩的推广应用。

  12. 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...... from BHT measurements in the presence of bore fluid invasion. The scheme is based on finite element analysis in conjunction with Markov chain Monte Carlo inversion. The axisymmetric forward model assumes a cylindrical source of finite radius and contrasting thermal parameters, which includes...... 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...

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

    National Research Council Canada - National Science Library

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

    2014-01-01

    ... (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...

  14. Respiratory Complications Associated with Insertion of Small-Bore Feeding Tube in Critically Ill Patients

    Directory of Open Access Journals (Sweden)

    Jeong Am Ryu

    2014-05-01

    Full Text Available Small-bore flexible feeding tubes decrease the risk of ulceration of the nose, pharynx, and stomach compared with large-bore and more rigid tubes. However, small-bore feeding tubes have more respiratory system complications, such as pneumothorax, hydropneumothorax, bronchopleural fistula, and pneumonia, which are associated with significant morbidity and mortality. Thus, it is important to confirm the correct position of feeding tubes. Chest X-ray is the gold standard to detect tracheal malpositioning of the feeding tube. We present three cases in which intubated patients exhibited an altered mental state. An assistant guide wire was used at the insertion of small-bore feeding tubes. These conditions are thought to be potential risk factors for tracheobronchial malpositioning of feeding tubes.

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

    National Research Council Canada - National Science Library

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

    2013-01-01

    .... 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...

  16. 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.

  17. Reservoir and production engineering aspects of slim-hole wells

    Energy Technology Data Exchange (ETDEWEB)

    Azari, Mehdi; Soliman, Mohamed; Pacheco, Eduardo [Halliburton Energy Services (United States)

    1994-12-31

    The purpose of this article is to provide insight into the reservoir and production engineering aspects of reservoirs with well bore and completion string diameters less than conventionally drilled and completed wells. In addition it will provide an answer to the question: `when should you hydraulically fracture a slim-hole well?` (author) 10 refs., 8 figs., 18 tabs.

  18. 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.

  19. Improvement of machining accuracy in precision micro-boring system by forecasting compensatory control technique

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents the design of a micro-boring servo system. A piezoelectric actuator is employed to compensate the deflection errors of the cutter in the radial direction to reduce the force-induced errors in the workpiece. In order to bore small and deep holes, the boring bar is designed with a new structure consisting of two concentric bars, one being used for error measuring and the other for error compensation. As a result, the size of the micro-boring bar is not af fected even after the piezoelectric actuator and strain gauges have been incorporated. The outer diameter of the boring bar used is 16 mm and the length to diameter ratio is greater than 9. A Forecasting Compensatory Control (FCC) technique is adopted in this system for error prediction and error compensation. The off-line forecasting compensatory control simulation and on-line cutting results have verified that the roundness form errors in the workpiece can be re duced up to 60 percent with the developed micro-boring servo system.

  20. 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)

  1. Seismic source characterisation of a Tunnel Boring Machine (TBM)

    Science.gov (United States)

    Kreutzer, Ingrid; Brückl, Ewald; Radinger, Alexander

    2015-04-01

    The Tunnel Seismic While Drilling (TSWD) method aims at predicting continuously the geological situation ahead of the tunnel without disturbing the construction work. Thereby the Tunnel Boring Machine (TBM) itself is used as seismic source. The cutting process generates seismic waves radiating into the rock mass and vibrations propagating to the main bearing of the cutter head. These vibrations are monitored and used as pilot signal. For the processing and interpretation it was hypothesized so far that the TBM acts like a single force. To prove this assumption the radiation pattern of several TBM's under construction were investigated. Therefore 3-components geophones were installed at the surface, which were situated directly above the tunnel axes and also with lateral offset. Additional, borehole geophones were placed in the wall of one tube of a two-tube tunnel. The geophones collected the forward and backward radiated wave field, as the TBM, operating in the other tube, passed their positions. The obtained seismic data contains continuous records over a range of 600 m of the TBM position. The offsets vary from 25 m to 400 m and the frequency ranges from 20-250 Hertz. The polarisation of the p-wave and the s-wave and their amplitude ratio were determined and compared with modelled seismograms with different source mechanism. The results show that the description of the source mechanism by a single force can be used as a first order approximation. More complex radiation pattern including tensile forces and several source locations like the transmission of reaction forces over the gripper to the tunnel wall are further tested and addressed.

  2. Down-bore two-laser heterodyne velocimetry of an implosion-driven hypervelocity launcher

    Science.gov (United States)

    Hildebrand, Myles; Huneault, Justin; Loiseau, Jason; Higgins, Andrew J.

    2017-01-01

    The implosion-driven launcher uses explosives to shock-compress helium, driving well-characterized projectiles to velocities exceeding 10 km/s. The masses of projectiles range between 0.1 - 15 g, and the design shows excellent scalability, reaching similar velocities across different projectile sizes. In the past, velocity measurements have been limited to muzzle velocity obtained via a high-speed videography upon the projectile exiting the launch tube. Recently, Photon Doppler Velocimetry (PDV) has demonstrated the ability to continuously measure in-bore velocity, even in the presence of significant blow-by of high temperature helium propellant past the projectile. While a single laser system sampled at 40 GS/s with a 13 GHz detector/scope bandwidth is limited to 8 km/s, a two-laser PDV system is developed that uses two lasers operating near 1550 nm to provide velocity measurement capabilities up to 16 km/s with the same bandwidth and sampling rate. The two-laser PDV system is used to obtain a continuous velocity history of the projectile throughout the entire launch cycle. These internal ballistics trajectories are used to compare different advanced concepts aimed at increasing the projectile velocity to well beyond 10 km/s.

  3. 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

  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. Damage Distributions

    DEFF Research Database (Denmark)

    Lützen, Marie

    2001-01-01

    the damage location, the damage sizes and the main particulars of the struck vessel. From the numerical simulation and the analyse of the damage statistics it is found that the current formulation from the IMO SLF 43/3/2 can be used as basis for determination of the p-, r-, and v-factors. Expressions...... and methods of calculation have been discussed. The damage distributions for the different vessels have been compared and analyses regarding relations between damage parameters and main particulars have been performed. The damage statistics collected in work package 1 have been analysed for relations between...... for the distribution of the non-dimensional damage location, the non-dimensional damage length and the non-dimensional penetrations have been derived. These distributions have been used as basis for a proposal for the p- and r-factors. Two proposals for the v-factor have been performed using the damage statistics...

  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. 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.

  8. 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.

  9. 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.

  10. Age, growth and mortality in four populations of the boring bivalve Lithophaga patagonica from Argentina

    Science.gov (United States)

    Bagur, María; Richardson, Christopher A.; Gutiérrez, Jorge L.; Arribas, Lorena P.; Doldan, M. Socorro; Palomo, M. Gabriela

    2013-08-01

    The boring bivalve Lithophaga patagonica (d'Orbigny, 1842) is a locally abundant inhabitant of hard substrata in the coastal waters of the Southwestern Atlantic. In this paper, we describe the growth, age and mortality of three intertidal rock-boring populations of L. patagonica and one subtidal oyster shell (Ostrea puelchana) boring population. An analysis of acetate peel replicas of shell sections showed that L. patagonica slows down its growth during autumn-winter, which leads to changes in the direction and rate of shell deposition and the formation of conspicuous annual (low temperature induced) clefts in the shell margin. Cleft counts and Von Bertalanffy growth analyses indicated that maximum age varies from 4 years in the oyster-boring population to 13 years in a rock-boring one (longevity estimates varied between 6.5 and 15 years, respectively). Maximum asymptotic length (L∞) and Von Bertalanffy growth constant (K) were also variable between populations (L∞ between 14.76 and 36.95 mm and K from 0.20 to 0.90 yr- 1 respectively). Mortality rates were higher at the two southernmost populations. Type (rock vs. oyster), composition and hardness of the substrata are likely the main factors controlling the observed differences between populations.

  11. 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.

  12. Sediment resuspension and the generation of intermediate nepheloid layers by shoaling internal bores

    Science.gov (United States)

    Masunaga, Eiji; Arthur, Robert S.; Fringer, Oliver B.; Yamazaki, Hidekatsu

    2017-06-01

    Numerical simulations of sediment resuspension due to shoaling internal bores are performed with a nonhydrostatic model, SUNTANS. Results show strong sediment resuspension induced by internal bores and a turbidity layer intruding offshore in the interior of the water column, known as an intermediate nepheloid layer (INL). Sediment resuspension processes and INLs reproduced in the model are in good agreement with observational data from Otuschi Bay, Japan. The formation of INLs by shoaling internal waves is explained as follows: (1) strong receding currents due to a previous run-up bore cause sediment resuspension along the slope, (2) the interaction of the receding currents and a subsequent run-up bore induce horizontal flow convergence and strong upward currents, (3) the upward currents lift the suspended sediments into the interior of the water column, (4) the run-up bore intrudes below the suspended sediments and forms an INL within the pycnocline. Sediment resuspension processes are also investigated for various internal Iribarren number conditions. The internal Iribarren number represents the ratio of the topographic slope to the internal wave steepness. In low internal Iribarren number conditions, strong currents near the bottom result in sediment resuspension and INL formation. In high internal Iribarren number conditions, sediment resuspension is weak, and INLs do not form.

  13. An integral transform approach for a mixed boundary problem involving a flowing partially penetrating well with infinitesimal well skin

    Science.gov (United States)

    Chang, Chien-Chieh; Chen, Chia-Shyun

    2002-06-01

    A flowing partially penetrating well with infinitesimal well skin is a mixed boundary because a Cauchy condition is prescribed along the screen length and a Neumann condition of no flux is stipulated over the remaining unscreened part. An analytical approach based on the integral transform technique is developed to determine the Laplace domain solution for such a mixed boundary problem in a confined aquifer of finite thickness. First, the mixed boundary is changed into a homogeneous Neumann boundary by substituting the Cauchy condition with a Neumann condition in terms of well bore flux that varies along the screen length and is time dependent. Despite the well bore flux being unknown a priori, the modified model containing this homogeneous Neumann boundary can be solved with the Laplace and the finite Fourier cosine transforms. To determine well bore flux, screen length is discretized into a finite number of segments, to which the Cauchy condition is reinstated. This reinstatement also restores the relation between the original model and the solutions obtained. For a given time, the numerical inversion of the Laplace domain solution yields the drawdown distributions, well bore flux, and the well discharge. This analytical approach provides an alternative for dealing with the mixed boundary problems, especially when aquifer thickness is assumed to be finite.

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

    Science.gov (United States)

    Saha, Aparna; Talukdar, B.; Das, Umapada; Chatterjee, Supriya

    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 is linear 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.

  15. Plasma dynamics near critical density inferred from direct measurements of laser hole boring.

    Science.gov (United States)

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

    2016-06-01

    We have used multiframe picosecond optical interferometry to make direct measurements of the hole boring velocity, v_{HB}, of the density cavity pushed forward by a train of CO_{2} laser pulses in a near critical density helium plasma. As the pulse train intensity rises, the increasing radiation pressure of each pulse pushes the density cavity forward and the plasma electrons are strongly heated. After the peak laser intensity, the plasma pressure exerted by the heated electrons strongly impedes the hole boring process and the v_{HB} falls rapidly as the laser pulse intensity falls at the back of the laser pulse train. A heuristic theory is presented that allows the estimation of the plasma electron temperature from the measurements of the hole boring velocity. The measured values of v_{HB}, and the estimated values of the heated electron temperature as a function of laser intensity are in reasonable agreement with those obtained from two-dimensional numerical simulations.

  16. Laser-driven hole boring and gamma-ray emission in high-density plasmas

    CERN Document Server

    Nerush, Evgeny

    2014-01-01

    Ion acceleration in laser-produced dense plasmas is a key topic of many recent investigations thanks to its potential applications. Besides, at forthcoming laser intensities ($I \\gtrsim 10^{23} \\text{W}\\,\\text{cm}^{-2}$) interaction of laser pulses with plasmas can be accompanied by copious gamma-ray emission. Here we demonstrate the mutual influence of gamma-ray emission and ion acceleration during relativistic hole boring in high-density plasmas with ultra-intense laser pulses. If gamma-ray emission is abundant, laser pulse reflection and hole-boring velocity are lower and gamma-ray radiation pattern is narrower than in the case of low emission. Conservation of energy and momentum allows one to elucidate the effects of gamma-ray emission which are more pronounced at higher hole-boring velocities.

  17. 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.

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

    Directory of Open Access Journals (Sweden)

    J. Fatome

    2014-05-01

    Full Text Available 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.

  19. 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.

  20. 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

  1. 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

  2. Analysis of a Rough Elliptic Bore Journal Bearing using Expectancy Model of Roughness Characterization

    Directory of Open Access Journals (Sweden)

    P.C. Mishra

    2014-06-01

    Full Text Available Performance characteristics of a rough elliptic bore journal bearing are studied. The bearing bore of isotropic roughness orientation is characterized by stochastic function and the film geometry is quantified to elliptic shape. There after the Reynolds equation and energy equation are descretized for pressure and temperature respectively. A finite difference model is developed to evaluate hydrodynamic pressure and oil temperature. Solution to this model is done using effective influence Newton-Raphson method. Performance parameters such as load bearing ability, friction, flow-in and side leakages are computed and discussed.

  3. 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.

  4. Damage evaluation system for materials used in fossil thermal power plants

    Energy Technology Data Exchange (ETDEWEB)

    Okamura, Hiroyuki [Science Univ. of Tokyo (Japan); Sakai, Shinsuke [Tokyo Univ. (Japan); Tomita, Akira [Japan Power Engineering and Inspection Corp., Tokyo (Japan); Koyama, Teruo [Babcock Hitachi K.K., Tokyo (Japan); Sakurai, Shigeo; Kawasaki, Yoshiya [Hitachi Ltd., Ibaraki (Japan)

    1998-11-01

    The summary of this research paper is as follows: The fundamental design of the damage evaluation system is carried out based on the basic concept. Prototype systems for boilers and turbines have been constructed: (a) Boiler: (I) Evaluation part: Outer surface of the primary pendant superheater tube; (II) Damage mode: Creep; (III) Damage evaluation method: Hardness measurement method; (b) Turbine: (I) Evaluation part: Inner surface at the center bore of high pressure turbine rotor; (II) Damage mode: Creep; (III) Damage evaluation method: Electric potential method. (orig./MM)

  5. Effect of dieldrin in the glue line of oak plywood panels in preventing Lyctus beetle damage

    Science.gov (United States)

    Thomas McIntyre

    1961-01-01

    For many years the lumber industry has been seeking improved methods of preventing decay and insect damage to lumber and other wood products. One relatively new approach to this problem is the addition of toxic chemicals in plywood glues to prevent infestations or restrict feeding injury by wood-boring insects. Wood products treated in this manner have been marketed in...

  6. In-bore prostate transperineal interventions with an MRI-guided parallel manipulator: system development and preliminary evaluation.

    Science.gov (United States)

    Eslami, Sohrab; Shang, Weijian; Li, Gang; Patel, Nirav; Fischer, Gregory S; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M; Iordachita, Iulian

    2016-06-01

    Robot-assisted minimally-invasive surgery is well recognized as a feasible solution for diagnosis and treatment of prostate cancer in humans. This paper discusses the kinematics of a parallel 4 Degrees-of-Freedom (DOF) surgical manipulator designed for minimally invasive in-bore prostate percutaneous interventions through the patient's perineum. The proposed manipulator takes advantage of four sliders actuated by MRI-compatible piezoelectric motors and incremental rotary encoders. Errors, mostly originating from the design and manufacturing process, need to be identified and reduced before the robot is deployed in clinical trials. The manipulator has undergone several experiments to evaluate the repeatability and accuracy (about 1 mm in air (in x or y direction) at the needle's reference point) of needle placement, which is an essential concern in percutaneous prostate interventions. The acquired results endorse the sustainability, precision and reliability of the manipulator. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  7. Well construction hydraulics in challenging environments; Hidraulica de construcao de pocos em cenarios criticos

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Andre Leibsohn; Folsta, Mauricio Gimenes; Waldmann, Alex Tadeu de Almeida; Gandelman, Roni Abensur [Centro de Pesquisas da Petrobras (CENPES). Gerencia de Interacao Rocha-Fluido (Brazil)], e-mails: aleibsohn@petrobras.com.br, folsta@petrobras.com.br, awaldmann@petrobras.com.br, roniag@petrobras.com.br; Aragao, Atila Fernando Lima [E and P Construcao de Pocos Maritimos. Gerencia de Tecnologia de Fluidos (Brazil)], e-mail: atila-aragao@petrobras.com.br; Aranha, Pedro Esteves [Centro de Pesquisas da Petrobras (CENPES). Gerencia de Perfuracao e Completacao de Pocos (Brazil)], e-mail: pearanha@petrobras.com.br

    2009-12-15

    This article reports the main R and D efforts on well bore construction hydraulics which facilitated the technological development of major Brazilian offshore fields in challenging scenarios. These include: deep and ultra deep water exploratory campaigns, inclined, horizontal and complex trajectory development wells, extended reach wells, long horizontal section wells and drilling through sensitive formations (heavy oil reservoirs, salt zones and fractured carbonates). The relevant scenarios, technical aspects, project development strategies, the history of well bore hydraulics in the main PETROBRAS R and D programs, as well as the contribution of Brazilian universities are detailed. (author)

  8. 盾构机姿态的人工测量原理%Manual measurement principle of tunnel boring machine attitude

    Institute of Scientific and Technical Information of China (English)

    黄小斌; 区兆铭; 张永超; 蒋样明

    2011-01-01

    The paper put forward the manual measurement principle of tunnel boring machine attitude for the oriented approach of the tunnel boring machine in Metro tunnel shield construction. It used the shield attitude solver in Excel to calculate the real-time tunnel boring machine attitude. It could be the timely guidance for correcting tunnel boring machine, and ensure the tunnel boring machine tunneling along the designed circuit.%本文针对地铁隧道盾构法施工中盾构机的导向方法,提出盾构机姿态的人工测量原理,通过在Excel中编辑的盾构掘进姿态解算程序来计算盾构机的实时掘进姿态,及时指导盾构机纠偏,确保盾构机按照设计的线路进行掘进.

  9. Construction cost management of bored pile%钻孔灌注桩施工成本管理

    Institute of Scientific and Technical Information of China (English)

    赵小利

    2012-01-01

    分析了钻孔灌注桩施工工艺的发展现状,结合当前钻孔灌注桩工程的施工形势,阐述了钻孔灌注桩施工成本管理的重要性,介绍了成本管理的理论,总结了钻孔灌注桩成本管理的基本方法,指出降低钻孔灌注桩施工成本的基本途径。%With an analysis on the construction technology development status of bored pile, combining with contemporary construction situation of bored pile engineering, the article describes the significance of bored pile construction cost management, introduces the cost management theo- ry, summarizes the basic methods of bored pile cost management, and finally points out ways of reducing bored pile construction cost.

  10. Phylogeography and limited genetic connectivity in the endangered boring giant clam across the Coral Triangle.

    Science.gov (United States)

    DeBoer, Timery S; Subia, Matthew D; Erdmann, Mark V; Kovitvongsa, Katie; Barber, Paul H

    2008-10-01

    The Coral Triangle is the global center of marine biodiversity; however, its coral reefs are critically threatened. Because of the bipartite life history of many marine species with sedentary adults and dispersive pelagic larvae, designing effective marine protected areas requires an understanding of patterns of larval dispersal and connectivity among geographically discrete populations. We used mtDNA sequence data to examine patterns of genetic connectivity in the boring giant clam (Tridacna crocea) in an effort to guide conservation efforts within the Coral Triangle. We collected an approximately 485 base pair fragment of mtDNA cytochrome c oxidase 1 (CO1) from 414 individuals at 26 sites across Indonesia. Genetic structure was strong between regions (phi(ST)=0.549, p < 0.00001) with 3 strongly supported clades: one restricted to western Sumatra, another distributed across central Indonesia, and a third limited to eastern Indonesia and Papua. Even within the single largest clade, small but significant genetic structure was documented (phi(ST)=0.069, p < 0.00001), which indicates limited gene flow within and among phylogeographic regions. Significant patterns of isolation by distance indicated an average dispersal distance of only 25-50 km, which is far below dispersal predictions of 406-708 km derived from estimates of passive dispersal over 10 days via surface currents. The strong regional genetic structure we found indicates potent limits to genetic and demographic connectivity for this species throughout the Coral Triangle and provides a regional context for conservation planning. The recovery of 3 distinct evolutionarily significant units within a well-studied taxonomic group suggests that biodiversity in this region may be significantly underestimated and that Tridacna taxa may be more endangered than currently recognized.

  11. An Account on marine wood-boring organisms of offshore waters of Bombay High, India

    Digital Repository Service at National Institute of Oceanography (India)

    Wagh, A.B.; Raveendran, T.V.

    An incidence of wood-boring organisms in a water column of 75 meters depth, 160 km off the Bombay coast is reported. The destruction of untreated panels of mango wood exposed for periods varying from 1-12 months was caused by eight species...

  12. 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...

  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. 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…

  15. Microbial control of wood-boring insects attacking forest and shade trees

    Science.gov (United States)

    Ann E. Hajek; Leah S. Bauer

    2007-01-01

    Wood-boring insect pests that feed on the bark, phloem, or xylem (wood) of living trees pose unique management challenges because their immature stages live in cryptic, often inaccessible, habitats within host trees. The eggs of wood borers are laid in or on tree trunks, branches, terminal shoots, or roots. After the eggs hatch, neonates tunnel in and feed on internal...

  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. Large or small bore, push or pull: a comparison of three classes of percutaneous fluoroscopic gastrostomy catheters.

    Science.gov (United States)

    Kuo, Yuo-Chen; Shlansky-Goldberg, Richard D; Mondschein, Jeffrey I; Stavropoulos, S William; Patel, Aalpen A; Solomon, Jeffrey A; Soulen, Michael C; Kwak, Andrew; Itkin, Maxim; Chittams, Jesse L; Trerotola, Scott O

    2008-04-01

    To compare the tube performance and complication rates of small-bore, large-bore push-type, and large-bore pull-type gastrostomy catheters. A total of 160 patients (74 men, 86 women; mean age, 66.9 years, range, 22-95 y) underwent percutaneous fluoroscopic gastrostomy placement between January 2004 and March 2006. Choice of catheter was based on the preference of the attending radiologist. Data were collected retrospectively with institutional review board approval. Radiology reports provided information on the catheter, indication for gastrostomy, technical success, and immediate outcome. Chart review provided data on medical history, postprocedural complications, progress to feeding goal, and clinical outcomes. Statistical analysis was performed to compare the three classes of gastrostomy catheters. All 160 catheters were placed successfully. Patients who received small-bore catheters (14 F; n = 88) had significantly more tube complications (17% vs 5.6%) and were less likely to meet their feeding goal (P = .035) compared with patients with large-bore catheters (20 F; n = 72). No difference was observed in terms of major or minor complications. Large-bore push-type (n = 14) and pull-type catheters (n = 58) were similar in terms of complication rates. Patients who received large-bore push-type catheters achieved their feeding goals in significantly less time than those with large-bore pull-type catheters (average, 3.8 days vs 6.0 days; P = .04). Patients who received small-bore gastrostomy catheters are significantly more prone to tube dysfunction. Large-bore catheters should be preferentially used, with push-type catheters performing better with regard to the time to achieve feeding goal.

  18. Flow and turbulence structure in a hypertidal estuary with the world's biggest tidal bore

    Science.gov (United States)

    Tu, Junbiao; Fan, Daidu

    2017-04-01

    Turbulent and flow structure associated with breaking tidal bores are deliberately investigated on the basis of field measurements. High-resolution velocity and hydrographic data are collected in the middle Qiantang Estuary by a vertical array of acoustic Doppler velocimeters and optical backscatter sensors, collaborated with a bottom-mounted acoustic Doppler current profiler. Besides obvious variations in diurnal and spring-neap tidal cycles, the estuarine dynamics is featured by extreme asymmetry in flood and ebb tides. The flood tide is abnormally accelerated to generate tidal bores at the first 10 min or more, with breaking or undular configurations at the front. The occurrence of peak flow velocity, turbulent kinetic energy (TKE), and TKE dissipation rate (ɛ) is definitely associated with breaking bores, with their values several times to 2 orders of magnitude larger than the corresponding secondary peak values during the maximum ebb flows. Flow and turbulence dynamics are significantly affected by the tidal-bore Froude number. A sandwich ɛ structure is clear exhibited with the maximum value at the surface, secondary maximum near the bed, and the minimum at the intermediate. Dual TKE sources are indicated by an approximate local balance between shear production and dissipation near the bottom, and a top-down TKE dissipation using the modified Froude scaling in the vertical water column. The highly elevated dissipation by breaking bores is comparable to that by intense breaking waves in the surf zone, and the former potentially penetrates the entire water column to produce extreme sediment-resuspension events in combination with intense bottom shear stress.

  19. The age and phylogeny of wood boring weevils and the origin of subsociality.

    Science.gov (United States)

    Jordal, Bjarte H; Sequeira, Andrea S; Cognato, Anthony I

    2011-06-01

    A large proportion of the hyperdiverse weevils are wood boring and many of these taxa have subsocial family structures. The origin and relationship between certain wood boring weevil taxa has been problematic to solve and hypotheses on their phylogenies change substantially between different studies. We aimed at testing the phylogenetic position and monophyly of the most prominent wood boring taxa Scolytinae, Platypodinae and Cossoninae, including a range of weevil outgroups with either the herbivorous or wood boring habit. Many putatively intergrading taxa were included in a broad phylogenetic analysis for the first time in this study, such as Schedlarius, Mecopelmus, Coptonotus, Dactylipalpus, Coptocorynus and allied Araucariini taxa, Dobionus, Psepholax, Amorphocerus-Porthetes, and some peculiar wood boring Conoderini with bark beetle behaviour. Data analyses were based on 128 morphological characters, rDNA nucleotides from the D2-D3 segment of 28S, and nucleotides and amino acids from the protein encoding gene fragments of CAD, ArgK, EF-1α and COI. Although the results varied for some of the groups between various data sets and analyses, one may conclude the following from this study: Scolytinae and Platypodinae are likely sister lineages most closely related to Coptonotus; Cossoninae is monophyletic (including Araucariini) and more distantly related to Scolytinae; Amorphocerini is not part of Cossoninae and Psepholax may belong to Cryptorhynchini. Likelihood estimation of ancestral state reconstruction of subsociality indicated five or six origins as a conservative estimate. Overall the phylogenetic results were quite dependent on morphological data and we conclude that more genetic loci must be sampled to improve phylogenetic resolution. However, some results such as the derived position of Scolytinae were consistent between morphological and molecular data. A revised time estimation of the origin of Curculionidae and various subfamily groups were made using

  20. 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.

  1. Exploitation technology of pressure relief coalbed methane in vertical surface wells in the Huainan coal mining area

    Institute of Scientific and Technical Information of China (English)

    HAN Jia-zhang; SANG Shu-xun; CHENG Zhi-zhong; HUANG Hua-zhou

    2009-01-01

    Exploitation technology of pressure relief coalbed methane in vertical surface wells is a new method for exploration of gas and coalbed methane exploitation in mining areas with high concentrations of gas, where tectonic coal developed. Studies on vertical surface well technology in the Huainan Coal Mining area play a role in demonstration in the use of clean, new energy re-sources, preventing and reducing coal mine gas accidents and protecting the environment. Based on the practice of gas drainage engineering of pressure relief coalbed methane in vertical surface wells and combined with relative geological and exploration en-gineering theories, the design principles of design and structure of wells of pressure relief coaibed methane in vertical surface wells are studied. The effects of extraction and their causes are discussed and the impact of geological conditions on gas production of the vertical surface wells are analyzed. The results indicate that in mining areas with high concentrations of gas, where tectonic coal developed, a success rate of pressure relief coalbed methane in surface vertical well is high and single well production usually great. But deformation due to coal exploitation could damage boreholes and cause breaks in the connection between aquifers and bore-holes, which could induce a decrease, even a complete halt in gas production of a single well. The design of well site location and wellbore configuration are the key for technology. The development of the geological conditions for coalbed methane have a sig-nificant effect on gas production of coalbed methane wells.

  2. Bone-boring worms: characterizing the morphology, rate, and method of bioerosion by Osedax mucofloris (Annelida, Siboglinidae).

    Science.gov (United States)

    Higgs, Nicholas D; Glover, Adrian G; Dahlgren, Thomas G; Little, Crispin T S

    2011-12-01

    Osedax worms possess unique "root" tissues that they use to bore into bones on the seafloor, but details of the boring pattern and processes are poorly understood. Here we use X-ray micro-computed tomography to investigate the borings of Osedax mucofloris in bones of the minke whale (Balaenoptera acutorostrata), quantitatively detailing their morphological characteristics for the first time. Comparative thin-sections of the borings reveal how the bone is eroded at the sub-millimeter level. On the basis of these results we hypothesize a model of boring that is dependent on the density and microstructure of the bone. We also present evidence of acidic mucopolysaccharides in the mucus of the root tissue, and hypothesize that this plays an important role in the boring mechanism. We discuss the utility of these new data in evaluating Osedax trace fossils and their relevance for O. mucofloris ecology. Measured rates of bone erosion (6% per year) and evidence of enhanced sulfide release from the borings indicate that Osedax worms are important habitat modifiers in whale-fall communities.

  3. A Hybrid Prediction Method of Thermal Extension Error for Boring Machine Based on PCA and LS-SVM

    Directory of Open Access Journals (Sweden)

    Cheng Qiang

    2017-01-01

    Full Text Available Thermal extension error of boring bar in z-axis is one of the key factors that have a bad influence on the machining accuracy of boring machine, so how to exactly establish the relationship between the thermal extension length and temperature and predict the changing rule of thermal error are the premise of thermal extension error compensation. In this paper, a prediction method of thermal extension length of boring bar in boring machine is proposed based on principal component analysis (PCA and least squares support vector machine (LS-SVM model. In order to avoid the multiple correlation and coupling among the great amount temperature input variables, firstly, PCA is introduced to extract the principal components of temperature data samples. Then, LS-SVM is used to predict the changing tendency of the thermally induced thermal extension error of boring bar. Finally, experiments are conducted on a boring machine, the application results show that Boring bar axial thermal elongation error residual value dropped below 5 μm and minimum residual error is only 0.5 μm. This method not only effectively improve the efficiency of the temperature data acquisition and analysis, and improve the modeling accuracy and robustness.

  4. 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)

  5. 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.

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

    Science.gov (United States)

    Enders, Judith; Zimmermann, Elke; Rief, Matthias; Martus, Peter; Klingebiel, Randolf; Asbach, Patrick; Klessen, Christian; Diederichs, Gerd; Wagner, Moritz; Teichgräber, Ulf; Bengner, Thomas; Hamm, Bernd; Dewey, Marc

    2011-01-01

    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. 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. 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). Even recent MR cannot prevent claustrophobia suggesting that further developments to create a more patient-centered MR scanner environment are needed. ClinicalTrials.gov NCT00715806.

  7. Vascular endothelial damage as well as changes in coagulation and anticoagulation function in psoriatic patients%银屑病患者血管内皮及凝血、抗凝血功能变化的观察

    Institute of Scientific and Technical Information of China (English)

    孙小强; 王璐; 门剑龙; 周之海

    2008-01-01

    psoriasis.Methods A total of 51 patients with psoriasis(29 at active stage and 22 at stable stage)were enrolled into this study,along with 50 normal controls.Twenty Patients with active psoriasis received treatment with daily introvenous Danshen injection,topical triamcinolone acetonide cream as well as oral clarithromycin when necessary.Coagulation analyzer ACL 9000 was used to measure the parameters related to endothelial damage,coagulation and anticoagulation system in these patients and controls.Psoriasis area and severity index(PASI)was used to evaluate these patients before and after the treatment.The correlation between PASI and the tested parameters was assessed.Results Compared with the normal controls.decreased antithrombin activity as well as protein C activity and antigen were observed in patients at active stage(69.2%±17.3%,80.4%±17.3%,74.1%±23.8%respectively)and in those at stable stage (84.6%±11.9%,93.1%±15.5%,95.2%±18.3%respectively),whereas increased levels of plasminogen activator inhibitor-1 and vW factor were found in active psoriatic patients(0.6±0.5 Au/L,100.7%±25.6%respectively)and in stable psoriatic patients(0.9±0.6 Au/L,141.6%±59.1%respectively).Patients with active psoriasis had a higher level of vW factor but a lower level of antithrombin and protein C activity than those with stable psoriasis(all P<0.01).After treatment,the levels of antithrombin activity as well as protein C activity and antigen in patients with active psoriasis increased to 79.5%±13.0%,87.6%±10.9%,86.9%±20.5% respectively.while the level of plasminogen activator inhibitor-1 and vW factor decreased to 1.0±0.86 Au/L and 172.8%±44.5% respectively(all P<0.01).The activity of blood coagulation factor Ⅷ was lower in pailents with stable psoriasis than in those with active psoriasis(129.4%±33.2%VS 156.2%±67.1%,P<0.01)but higher than in the normal controls(P<0.01).No significant difierence was noticed in PASI before and after the treatment.and there was no

  8. Fiscal year 1996 well plugging and abandonment program Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This report is a synopsis of the progress of the well plugging and abandonment program at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, from August 1995 through August 1996. A total of 27 wells, piezometers, and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the U.S. Department of Energy, Y-12 Plant, Oak Ridge, Tennessee (HSW, Inc. 1991).

  9. A two-compartment phantom for VOI profile measurements in small-bore 31P MR spectroscopy

    DEFF Research Database (Denmark)

    Vikhoff, Babro; Stubgaard, Max; Stensgaard, Anders

    1998-01-01

    A two-compartment gel phantom for VOI profile measurements in volume-selective 31P spectroscopy in small-bore units is presented. The phantom is cylindrical with two compartments divided by a very thin (30 microm) polyethene film. This thin film permits measurements with a minimum of susceptibility...... from the two compartments was measured for each position and the data were evaluated following differentiation. We have found this phantom suitable for VOI profile measurements of ISIS in small-bore systems. The phantom forms a useful complement to recommended phantoms for small bore-spectroscopy...

  10. 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.)

  11. 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

  12. 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.

  13. 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.

  14. 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...... from BHT measurements in the presence of bore fluid invasion. The scheme is based on finite element analysis in conjunction with Markov chain Monte Carlo inversion. The axisymmetric forward model assumes a cylindrical source of finite radius and contrasting thermal parameters, which includes...... 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...

  15. High Frequency Field Measurements of an Undular Bore Using a 2D LiDAR Scanner

    Directory of Open Access Journals (Sweden)

    Kévin Martins

    2017-05-01

    Full Text Available The secondary wave field associated with undular tidal bores (known as whelps has been barely studied in field conditions: the wave field can be strongly non-hydrostatic, and the turbidity is generally high. In situ measurements based on pressure or acoustic signals can therefore be limited or inadequate. The intermittent nature of this process in the field and the complications encountered in the downscaling to laboratory conditions also render its study difficult. Here, we present a new methodology based on LiDAR technology to provide high spatial and temporal resolution measurements of the free surface of an undular tidal bore. A wave-by-wave analysis is performed on the whelps, and comparisons between LiDAR, acoustic and pressure-derived measurements are used to quantify the non-hydrostatic nature of this phenomenon. A correction based on linear wave theory applied on individual wave properties improves the results from the pressure transducer (Root mean square error, R M S E of 0 . 19 m against 0 . 38 m; however, more robust data is obtained from an upwards-looking acoustic sensor despite high turbidity during the passage of the whelps ( R M S E of 0 . 05 m. Finally, the LiDAR scanner provides the unique possibility to study the wave geometry: the distribution of measured wave height, period, celerity, steepness and wavelength are presented. It is found that the highest wave from the whelps can be steeper than the bore front, explaining why breaking events are sometimes observed in the secondary wave field of undular tidal bores.

  16. 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

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

    OpenAIRE

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

    2013-01-01

    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 P...

  18. The Time and Cost Prediction of Tunnel Boring Machine in Tunnelling

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Making use of microsoft visual studio. net platform, the assistant decision-making system of tunnel boring machine in tunnelling has been built to predict the time and cost. Computation methods of the performance parameters have been discussed. New time and cost prediction models have been depicted. The multivariate linear regression has been used to make the parameters more precise, which are the key factor to affect the prediction near to the reality.

  19. Long time existence results for bore-type initial data for BBM-Boussinesq systems

    Science.gov (United States)

    Burtea, Cosmin

    2016-11-01

    In this paper we deal with the long time existence for the Cauchy problem associated to BBM-type Boussinesq systems of equations which are asymptotic models for long wave, small amplitude gravity surface water waves. As opposed to previous papers devoted to the long time existence issue, we consider initial data with nontrivial behavior at infinity which may be used to model bore propagation.

  20. 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.

  1. 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.

  2. Chemical and mechanical bioerosion of boring sponges from Mexican Pacific coral reefs.

    Science.gov (United States)

    Nava, Héctor; Carballo, José Luis

    2008-09-01

    Species richness (S) and frequency of invasion (IF) by boring sponges on living colonies of Pocillopora spp. from National Park Isla Isabel (México, East Pacific Ocean) are presented. Twelve species belonging to the genera Aka, Cliona, Pione, Thoosa and Spheciospongia were found, and 56% of coral colonies were invaded by boring sponges, with Cliona vermifera Hancock 1867 being the most abundant species (30%). Carbonate dissolution rate and sediment production were quantified for C. vermifera and Cliona flavifodina Rützler 1974. Both species exhibited similar rates of calcium carbonate (CaCO3) dissolution (1.2+/-0.4 and 0.5+/-0.2 kg CaCO3 m(-2) year(-1), respectively, mean +/- s.e.m.), and sediment production (3.3+/-0.6 and 4.6+/-0.5 kg CaCO3 m(-2) year(-1)), resulting in mean bioerosion rates of 4.5+/-0.9 and 5.1+/-0.5 kg CaCO3 m(-2) year(-1), respectively. These bioerosion rates are close to previous records of coral calcification per unit of area, suggesting that sponge bioerosion alone can promote disequilibrium in the reef accretion/destruction ratio in localities that are heavily invaded by boring sponges. The proportion of dissolved material by C. vermifera and C. flavifodina (27 and 10.2%, respectively) confirms that chemical bioerosion plays an important role in sponge bioerosion and in the CaCO3 cycle in coral reefs.

  3. 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.

  4. Chatter reduction in boring process by using piezoelectric shunt damping with experimental verification

    Science.gov (United States)

    Yigit, Ufuk; Cigeroglu, Ender; Budak, Erhan

    2017-09-01

    Chatter is a self-excited type of vibration that develops during machining due to process-structure dynamic interactions resulting in modulated chip thickness. Chatter is an important problem as it results in poor surface quality, reduced productivity and tool life. The stability of a cutting process is strongly influenced by the frequency response function (FRF) at the cutting point. In this study, the effect of piezoelectric shunt damping on chatter vibrations in a boring process is studied. In piezoelectric shunt damping method, an electrical impedance is connected to a piezoelectric transducer which is bonded on cutting tool. Electrical impedance of the circuit consisting of piezoceramic transducer and passive shunt is tuned to the desired natural frequency of the cutting tool in order to maximize damping. The optimum damping is achieved in analytical and finite element models (FEM) by using a genetic algorithm focusing on the real part of the tool point FRF rather than the amplitude. Later, a practical boring bar is considered where the optimum circuit parameters are obtained by the FEM. Afterwards, the effect of the optimized piezoelectric shunt damping on the dynamic rigidity and absolute stability limit of the cutting process are investigated experimentally by modal analysis and cutting tests. It is both theoretically and experimentally shown that application of piezoelectric shunt damping results in a significant increase in the absolute stability limit in boring operations.

  5. 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.

  6. 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.

  7. 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.

  8. Hanford wells

    Energy Technology Data Exchange (ETDEWEB)

    McGhan, V.L.; Damschen, D.W.

    1977-06-01

    The Hanford Site contains about 2200 wells constructed from pre-Hanford Works days to the present. As of June 1977, about 1900 wells still exist, and about 850 of these existing wells were drilled to the ground-water table. About 700 of these wells (including about 24 farm wells) still contain water. The others have become dry through infiltration of sediments or a general lowering of the water table in their vicinity. This report, providing the most complete documentation of wells in and adjacent to the Hanford Site, supersedes all previous compilations of Hanford wells.

  9. 牵引电机抱轴瓦镗瓦工艺及专用镗床设计%Traction Motor Bearing Hold and Boring Tile Technics and Special Boring Machine Design

    Institute of Scientific and Technical Information of China (English)

    王威; 孟广耀; 韩小燕; 刘松年

    2011-01-01

    The traction motor bearing boring tile hold process was studied out, and the traction motor bearings hold the content boring tile process was designed and stipulated in detail. The shaft bushing boring of special machine tools was designed and developod. A thimble used in boring motor was adopted as the main shaft bearing positioning clamp device-oriented self-positioning device,and used to increase the single-edged knife boring axial stiffness and positioning accuracy, the appropriate power head, hydraulic slide sets, and linear guide was selected to complete the boring of the feed motion.%拟定牵引电机抱轴瓦镗瓦工艺流程,并详细设计与制定牵引电机抱轴瓦镗瓦工序内容.设计开发了镗削抱轴轴瓦加工的专用机床,采用顶针作为镗削电机抱轴轴瓦的主要定位夹紧装置,导向自定位装置用来提高单刃镗刀的轴向刚度和定位精度,选取合适的动力头、液压滑台和直线导轨来完成镗削的进给运动.

  10. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  11. The Boring Volcanic Field of the Portland-Vancouver area, Oregon and Washington: tectonically anomalous forearc volcanism in an urban setting

    Science.gov (United States)

    Evarts, Russell C.; Conrey, Richard M.; Fleck, Robert J.; Hagstrum, Jonathan T.; O'Connor, Jim; Dorsey, Rebecca; Madin, Ian P.

    2009-01-01

    More than 80 small volcanoes are scattered throughout the Portland-Vancouver metropolitan area of northwestern Oregon and southwestern Washington. These volcanoes constitute the Boring Volcanic Field, which is centered in the Neogene Portland Basin and merges to the east with coeval volcanic centers of the High Cascade volcanic arc. Although the character of volcanic activity is typical of many monogenetic volcanic fields, its tectonic setting is not, being located in the forearc of the Cascadia subduction system well trenchward of the volcanic-arc axis. The history and petrology of this anomalous volcanic field have been elucidated by a comprehensive program of geologic mapping, geochemistry, 40Ar/39Ar geochronology, and paleomag-netic studies. Volcanism began at 2.6 Ma with eruption of low-K tholeiite and related lavas in the southern part of the Portland Basin. At 1.6 Ma, following a hiatus of ~0.8 m.y., similar lavas erupted a few kilometers to the north, after which volcanism became widely dispersed, compositionally variable, and more or less continuous, with an average recurrence interval of 15,000 yr. The youngest centers, 50–130 ka, are found in the northern part of the field. Boring centers are generally monogenetic and mafic but a few larger edifices, ranging from basalt to low-SiO2 andesite, were also constructed. Low-K to high-K calc-alkaline compositions similar to those of the nearby volcanic arc dominate the field, but many centers erupted magmas that exhibit little influence of fluids derived from the subducting slab. The timing and compositional characteristics of Boring volcanism suggest a genetic relationship with late Neogene intra-arc rifting.

  12. Response of OH, O 2 and OI5577 airglow emissions to the mesospheric bore in the equatorial region of Brazil

    Science.gov (United States)

    Medeiros, A. F.; Fechine, J.; Buriti, R. A.; Takahashi, H.; Wrasse, C. M.; Gobbi, D.

    An all-sky CCD imager capable of measuring wave structure in the airglow OH, O 2 and OI (557.7 nm) emissions was operated in the equatorial region at São João do Cariri (Cariri), Brazil (7°S, 36°W), in collaboration with the Instituto Nacional de Pesquisas Espaciais (INPE). Occurrence of mesospheric bore events was studied using the data from September 2000 to September 2002. Sixty-four bore events were detected during the observation period. Most of the bores showed the complementary effects suggested by Dewan and Picard [E.M. Dewan, R.H. Picard, Mesospheric bores. Journal of Geophysical Research 103, 6295-6305, 1998], except in a few cases where the relative variations were inconsistent with this model.

  13. On construction and control over bored piles%谈钻孔灌注桩的施工与控制

    Institute of Scientific and Technical Information of China (English)

    刘广

    2014-01-01

    According to the construction practice of the bored piles in projects, the paper illustrates the construction controlling points for the bored piles, and researches the defects reasons for the underwater concrete bored piles, including the pipe blockage, leakage, floating of rein-forced cage, and hollowness of pile tops, and their prevention measures, so as to ensure the construction quality of the bored pile.%通过钻孔灌注桩在桥梁工程中的施工实践,阐述了钻孔灌注桩的施工控制要点,并对水下混凝土灌注桩出现的导管堵塞、漏水、钢筋笼上浮、桩顶空心等缺陷的成因及防治措施进行了研究,以确保钻孔灌注桩的施工质量。

  14. Development of Neural Network Model for Predicting Peak Ground Acceleration Based on Microtremor Measurement and Soil Boring Test Data

    National Research Council Canada - National Science Library

    Kerh, T; Lin, J. S; Gunaratnam, D

    2012-01-01

    .... This paper is therefore aimed at developing a neural network model, based on available microtremor measurement and on-site soil boring test data, for predicting peak ground acceleration at a site...

  15. Well Spacing for Horizontal Wells

    Directory of Open Access Journals (Sweden)

    C.D.S. Keuengoua

    2011-06-01

    Full Text Available In the developing phase of a hydrocarbon reservoir and planning for drilling the production wells, it is necessary to drill the wells in an appropriate spacing to achieve maximum economic revenues during the reservoir life span. Well spacing which is the real location and interrelationship between producing oil or gas wells in an oil field is an important parameter. It is determined for the maximum ultimate production of a given reservoir and should be taken in consideration during well planning to avoid drilling of unnecessary wells. This study presents the concept of drainage area on horizontal well and horizontal productivity indices with different equations and their applications. A user friendly Excel Spreadsheet program was developed to calculate the productivity values of horizontal wells using three major available productivity equations. Also, the developed spreadsheet program was used to evaluate the effect of well spacing on the productivities of horizontal wells using productivity index approach and drainage area concept. It also helps to review the comparison between vertical and horizontal wells spacing based on drainage area concept. This program was validated, and then was used to study the effect of horizontal well length on the ratio of horizontal well productivity to vertical well productivity. The results show that higher ratio of horizontal well productivity to vertical well productivity values are obtained with increase length of the horizontal well. It is a very useful tool for making decision about the application of well spacing for horizontal wells.

  16. 40 CFR 144.28 - Requirements for Class I, II, and III wells authorized by rule.

    Science.gov (United States)

    2010-07-01

    ... annular pressure; (iii) The results from ground-water monitoring wells prescribed in paragraph (g)(1)(iii... drinking water and the well bore is prohibited. (2) The owner or operator of a Class I, II or III injection... water. (ii) For Class II wells: (A) The owner or operator shall not exceed a maximum injection...

  17. Catalytic destruction of groundwater contaminants in reactive extraction wells

    Energy Technology Data Exchange (ETDEWEB)

    McNab, Jr., Walt W. (Concord, CA); Reinhard, Martin (Stanford, CA)

    2002-01-01

    A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

  18. 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). ...

  19. Tort Damages

    NARCIS (Netherlands)

    L.T. Visscher (Louis)

    2008-01-01

    textabstractAbstract: In this Chapter, I provide an overview of Law and Economics literature regarding tort damages. Where necessary, attention is also spent to rules of tort liability. Both types of rules provide behavioral incentives to both injurers and victims, with respect to their level of

  20. Tort Damages

    NARCIS (Netherlands)

    L.T. Visscher (Louis)

    2008-01-01

    textabstractAbstract: In this Chapter, I provide an overview of Law and Economics literature regarding tort damages. Where necessary, attention is also spent to rules of tort liability. Both types of rules provide behavioral incentives to both injurers and victims, with respect to their level of car

  1. 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.

  2. Hanford wells

    Energy Technology Data Exchange (ETDEWEB)

    McGhan, V.L.

    1989-06-01

    The Site Characterization and Assessment Section of the Geosciences Department at Pacific Northwest Laboratory (PNL) has compiled a list of wells located on or near the Hanford Site. Information has been updated on wells existing from the days before construction of the Hanford Works to the present. This work was funded by the US Department of Energy (DOE). The list of wells will be used by DOE contractors who need condensed, tabular information on well location, construction, and completion dates. This report does not include data on lithologic logs and ground-water contamination. Moreover, the completeness of this list is limited because of new well construction and existing well modifications, which are continually under way. Despite these limitations, this list represents the most complete description possible of data pertaining to wells on or adjacent to the Hanford Site. 7 refs., 1 fig., 2 tabs.

  3. 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.

  4. Hanford wells

    Energy Technology Data Exchange (ETDEWEB)

    Chamness, M.A.; Merz, J.K.

    1993-08-01

    Records describing wells located on or near the Hanford Site have been maintained by Pacific Northwest Laboratory and the operating contractor, Westinghouse Hanford Company. In support of the Ground-Water Surveillance Project, portions of the data contained in these records have been compiled into the following report, which is intended to be used by those needing a condensed, tabular summary of well location and basic construction information. The wells listed in this report were constructed over a period of time spanning almost 70 years. Data included in this report were retrieved from the Hanford Envirorunental Information System (HEIS) database and supplemented with information not yet entered into HEIS. While considerable effort has been made to obtain the most accurate and complete tabulations possible of the Hanford Site wells, omissions and errors may exist. This document does not include data on lithologic logs, ground-water analyses, or specific well completion details.

  5. 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.

  6. A modified calculation model for groundwater flowing to horizontal seepage wells

    Indian Academy of Sciences (India)

    Wei Wang; Peng Chen; Qingqing Zheng; Xinyu Zheng; Kunming Lu

    2013-04-01

    The simulation models for groundwater flowing to horizontal seepage wells proposed by Wang and Zhang (2007) are based on the theory of coupled seepage-pipe flow model which treats the well pipe as a highly permeable medium. However, the limitations of the existing model were found during applications. Specifically, a high-resolution grid is required to depict the complex structure of horizontal seepage wells; the permeability of the screen or wall material of radiating bores is usually neglected; and the irregularly distributed radiating bores cannot be accurately simulated. A modified calculation model of groundwater flowing to a horizontal seepage well is introduced in this paper. The exchange flow between well pipe and aquifer couples the turbulent flow inside the horizontal seepage well with laminar flow in the aquifer. The modified calculation model can reliably calculate the pumpage of a real horizontal seepage well. The characteristics of radiating bores, including the diameter, the permeability of screen material and irregular distribution of radiating bores, can be accurately depicted using the modified model that simulates the scenario in which several horizontal seepage wells work together.

  7. 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.

  8. 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.

  9. 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

  10. Bore formation, evolution and disintegration into solitons in shallow inhomogeneous channels

    Directory of Open Access Journals (Sweden)

    J.-G. Caputo

    2003-01-01

    Full Text Available The propagation of nonlinear surface waves in channels of smoothly variable in space cross section is studied theoretically and by means of numerical computations. The mathematical model describing wave evolution is based on the generalized Korteweg-de Vries equation with additional terms due to spatial inhomogeneity and energy dissipation. Specifically we consider channels of variable depth and width. The breaking of Riemann waves and the disintegration of hydraulic jumps into trains of solitons have been examined. The results obtained can be useful in particular for the understanding some peculiarities of bore (mascaret formation, viscous evolution and disintegration into solitons in inhomogeneous channels or rivers.

  11. 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.

  12. A new species of seagrass-boring Limnoria (Limnoriidae, Isopoda, Crustacea) from Japan.

    Science.gov (United States)

    Yoshino, Hiroki; Watabe, Hikari; Ohsawa, Takeshi A

    2017-02-15

    The marine seagrass-boring isopod, Limnoria rhombipunctata sp. nov. (Limnoriidae) is described from the rhizome of Phyllospadix iwatensis seagrass, in shallow coastal waters off Chiba Prefecture, Japan. L. rhombipunctata sp. nov. is distinguished from other Limnoria species by the unique carinae of pleonite 5 and pleotelson, two branched lacinia mobilis of the right mandible, 3 flagellar articles of antenna 1, and triangular epipod of the maxilliped. Specimens of L. magadanensis, a species similar to L. rhombipunctata sp. nov., are re-examined and compared with L. rhombipunctata sp. nov.

  13. 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.

  14. 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.

  15. A case study of a mesospheric bore event observed with an all-sky airglow imager at Tirunelveli (8.7°N)

    Science.gov (United States)

    Narayanan, V. Lakshmi; Gurubaran, S.; Emperumal, K.

    2009-04-01

    A prominent front separating bright and dark regions of all-sky airglow images was recorded on the night of 22/23 March 2007, at the low-latitude Indian station Tirunelveli (8.7°N, 77.8°E) and is attributed to a mesospheric bore. With the help of complementary wind information from the colocated MF radar and temperature and density data from the SABER instrument onboard TIMED mission, the parameters of the bore are calculated and discussed. Because the observed wind at the emission altitude was orthogonal to the direction of bore propagation, Doppler ducting was not likely to support the bore. The analysis that makes use of the square of buoyancy frequency profiles reveals a thermal duct that would provide favorable conditions for the propagation of the bore. This is the first report of a mesospheric bore event from the Indian sector.

  16. Militantly Well

    DEFF Research Database (Denmark)

    Vigh, Henrik Erdman

    2015-01-01

    futures that transcend conflict engagement and wartime suffering for young militiamen. It clarifies the positive prospects that are expected to lie beyond the known horrors of war. Though conflict and warfare may provide strange points of departure for talking about well-being, imaginaries of happiness...... stand out from a background of hardship and are talked about in both a quite concrete way, as a lack of insecurity, as well as in an abstract way, as realization of social being. However, for most of the people I talk to, happiness remains elusive and evades their desperate attempts to grasp it....... It appears, as such, simultaneously to be what life is most profoundly about, as well as the dimension of it that constantly seems to avoid capture....

  17. Assessing Tropical Cyclone Damage

    Science.gov (United States)

    Done, J.; Czajkowski, J.

    2012-12-01

    Landfalling tropical cyclones impact large coastal and inland areas causing direct damage due to winds, storm-surge flooding, tornadoes, and precipitation; as well as causing substantial indirect damage such as electrical outages and business interruption. The likely climate change impact of increased tropical cyclone intensity, combined with increases in exposure, bring the possibility of increased damage in the future. A considerable amount of research has focused on modeling economic damage due to tropical cyclones, and a series of indices have been developed to assess damages under climate change. We highlight a number of ways this research can be improved through a series of case study analyses. First, historical loss estimates are revisited to properly account for; time, impacted regions, the source of damage by type, and whether the damage was direct/indirect and insured/uninsured. Second, the drivers of loss from both the socio-economic and physical side are examined. A case is made to move beyond the use of maximum wind speed to more stable metrics and the use of other characteristics of the wind field such as direction, degree of gustiness, and duration is explored. A novel approach presented here is the potential to model losses directly as a function of climate variables such as sea surface temperature, greenhouse gases, and aerosols. This work is the first stage in the development of a tropical cyclone loss model to enable projections of losses under scenarios of both socio-economic change (such as population migration or altered policy) and physical change (such as shifts in tropical cyclone activity one from basin to another or within the same basin).

  18. Liver Wellness

    Science.gov (United States)

    ... can cause the liver to swell and not work well. Prevention: Hepatitis A vaccination is the best way to prevent HAV. Other ways to stop the spread of HAV are: • Always washing your hands with soap and warm water immediately after using the bathroom ...

  19. Wellness Matters

    Science.gov (United States)

    Arteaga, Brenda

    2011-01-01

    Creating a healthier school in today's world of budget cuts and seemingly endless to-do lists is not only possible, but it is also imperative. Beyond the health implications, one of the most compelling reasons for creating healthier schools is that wellness serves as a power booster for learning. Numerous studies have documented what educators…

  20. Wellness Matters

    Science.gov (United States)

    Arteaga, Brenda

    2011-01-01

    Creating a healthier school in today's world of budget cuts and seemingly endless to-do lists is not only possible, but it is also imperative. Beyond the health implications, one of the most compelling reasons for creating healthier schools is that wellness serves as a power booster for learning. Numerous studies have documented what educators…

  1. Werable wellness

    DEFF Research Database (Denmark)

    Rozycki, Bartosz

    2015-01-01

    We live in a world full of rush and a ‘relaxed state of being’ might increasingly play a role in today’s fast paced society to overcome contemporary stress and related illnesses such as burn-outs. The Sleephones concept is a wearable wellness device that aims to support relaxation by combing music...

  2. High-resistance controlled yielding supporting technique in deep-well oil shale roadways

    Institute of Scientific and Technical Information of China (English)

    Yu Yang; Bai Jianbiao; Wang Xiangyu; Wang Junde; Xue Shizhi; Xu Ke

    2014-01-01

    In order to avoid the deep-well oil shale roadway being deformed, damaged, or difficult to maintain after excavating and supporting in Haishiwan coal mine, this paper has analyzed the characteristics of the deformed roadway and revealed its failure mechanism by taking comprehensively the methods of field geological investigation, displacement monitoring of surrounding rock, rock properties and hydration properties experiments and field application tests. Based on this work, the high-resistance controlled yielding supporting principle is proposed, which is:to‘resist’ by high pre-tightening force and high stiff-ness in the early stage, to‘yield’ by making use of the controlled deformation of a yielding tube in the middle stage, and to‘fix’ by applying total-section Gunite in the later stage. A high-resistance controlled yielding supporting technique of‘high pre-tightening force yielding anchor bolt+small-bore pre-tight-ening force anchor cable+rebar ladder beam+rhombic metal mesh+lagging gunite’ has been estab-lished, and industrial on site testing implemented. The practical results show that the high-resistance controlled yielding supporting technique can effectively control the large deformation and long-time rhe-ology of deep-well oil shale roadways and can provide beneficial references for the maintenance of other con-generic roadways.

  3. Mud and cement for horizontal wells

    Energy Technology Data Exchange (ETDEWEB)

    Zurdo, C.; Georges, C.; Martin, M.

    1986-01-01

    High-angle and horizontal well bores raise many questions concerning the characteristics of mud and cement. This paper is a summary of the authors' knowledge and work on these two subjects. For all research carried out, large or full-scale laboratory test plants were used. Cutting transport is not only a problem in horizontal conditions but hole angles of 25 to 65/sup 0/ can be even more critical when parameters such as mud rheological properties and velocities are not optimized. Drilling a long horizontal drain creates a dynamic annulus pressure unbalance. This can lead to a loss and kick situation. Two test benches were thus used to obtain a good understanding of the inefficiency of conventional plugging methods and of the difficulties of gas migration control in subhorizontal well bores. High concentrations of LCM, high rheological properties of fluids and low flow rates increase the changes of solving the first problem. The results of the second bench demonstrate the difficulties of annulus gas evacution for angles varying from 90 to 100 degrees, or from over-gauged sections in horizontal holes.

  4. 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.

  5. Linking Planktonic Larval Abundance to Internal Bores at the Head of the Monterey Submarine Canyon.

    Science.gov (United States)

    Phelan, J.; Walter, R. K.; Steinbeck, J. R.

    2015-12-01

    Variability in the physical coastal environment can play an important role in determining the spatio-temporal variation in abundance of planktonic organisms. Combining planktonic larval abundance estimates over the course of a year with concurrent temperature and current data, this study provides empirical data linking a locally predominant internal tidal feature to patterns of biological abundance in the very nearshore environment at the head of Monterey Submarine Canyon. The physical observations indicate the presence of seasonally-variable semidiurnal internal bores that result in the pumping of cold (subthermocline) waters onto the adjacent shelf. Analysis of the larval abundance data indicates an assemblage shift from a relatively abundant shelf assemblage of larval fishes to a reduced abundance assemblage that is concurrent with the semidiurnal cold water intrusions driven by the tidal pumping. Results suggest that the tidal period pumping of subthermocline waters by internal bores dilutes or displaces shelf waters and their associated planktonic larval community. This could have important ecological implications at these scales and may also be of interest when siting industrial facilities that require seawater for cooling or desalination, as it would potentially reduce their impact on regional planktonic communities by diluting their rates of entrainment.

  6. Identification of rock mass characteristics using microtremor in the boring hole

    Science.gov (United States)

    Che, Ailan; Wang, Huan; Feng, Shaokong; Siguyama, Takeshi

    2014-05-01

    An identification analysis method of the rock mass characteristics is proposed using microtremor measurements in the boring hole. The method is based on the assumption that the epicenter of incident waves of each observation point in the same boring hole almost agrees. And the calculations are deconvoluted by the multiple reflection theory. The procedure applicable to the identification of the average elastic characteristics of in situ rock masses is presented. It is based on the minimization of an error function representing the difference between microtremor measurements performed on the rock mass and the corresponding data obtained by a numerical analysis subjected to known external actions. The method requires the formulation of the elasticity inverse problem and is based on the least square minimization procedure. As an example the approach has been applied to the identification of the dynamic properties and the predominant characteristics of the rock mass underlying a deep excavated quarry in west of Shanghai city. The inverted rock mass characteristics are compared with the PS logs at the sites and show consistency, confirming that the proposed inversion is promising.

  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. 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.

  9. 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.

  10. Boring but important: a self-transcendent purpose for learning fosters academic self-regulation.

    Science.gov (United States)

    Yeager, David S; Henderson, Marlone D; Paunesku, David; Walton, Gregory M; D'Mello, Sidney; Spitzer, Brian J; Duckworth, Angela Lee

    2014-10-01

    Many important learning tasks feel uninteresting and tedious to learners. This research proposed that promoting a prosocial, self-transcendent purpose could improve academic self-regulation on such tasks. This proposal was supported in 4 studies with over 2,000 adolescents and young adults. Study 1 documented a correlation between a self-transcendent purpose for learning and self-reported trait measures of academic self-regulation. Those with more of a purpose for learning also persisted longer on a boring task rather than giving in to a tempting alternative and, many months later, were less likely to drop out of college. Study 2 addressed causality. It showed that a brief, one-time psychological intervention promoting a self-transcendent purpose for learning could improve high school science and math grade point average (GPA) over several months. Studies 3 and 4 were short-term experiments that explored possible mechanisms. They showed that the self-transcendent purpose manipulation could increase deeper learning behavior on tedious test review materials (Study 3), and sustain self-regulation over the course of an increasingly boring task (Study 4). More self-oriented motives for learning--such as the desire to have an interesting or enjoyable career--did not, on their own, consistently produce these benefits (Studies 1 and 4).

  11. 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.

  12. Boring but Important: A Self-Transcendent Purpose for Learning Fosters Academic Self-Regulation

    Science.gov (United States)

    Yeager, David S.; Henderson, Marlone D.; D’Mello, Sidney; Paunesku, David; Walton, Gregory M.; Spitzer, Brian J.; Duckworth, Angela Lee

    2015-01-01

    Many important learning tasks feel uninteresting and tedious to learners. This research proposed that promoting a prosocial, self-transcendent purpose could improve academic self-regulation on such tasks. This proposal was supported in four studies with over 2,000 adolescents and young adults. Study 1 documented a correlation between a self-transcendent purpose for learning and self-reported trait measures of academic self-regulation. Those with more of a purpose for learning also persisted longer on a boring task rather than giving in to a tempting alternative, and, many months later, were less likely to drop out of college. Study 2 addressed causality. It showed that a brief, one-time psychological intervention promoting a self-transcendent purpose for learning could improve high school science and math GPA over several months. Studies 3 and 4 were short-term experiments that explored possible mechanisms. They showed that the self-transcendent purpose manipulation could increase deeper learning behavior on tedious test review materials (Study 3), and sustain self-regulation over the course of an increasingly-boring task (Study 4). More self-oriented motives for learning—such as the desire to have an interesting or enjoyable career—did not, on their own, consistently produce these benefits (Studies 1 and 4). PMID:25222648

  13. 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...

  14. 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.

  15. Can electron multipacting explain the pressure rise in a cold bore superconducting undulator?

    Directory of Open Access Journals (Sweden)

    S. Casalbuoni

    2010-07-01

    Full Text Available Preliminary studies performed with the cold bore superconducting undulator installed in the ANKA (Angstrom source Karlsruhe storage ring suggest that the beam heat load is mainly due to the electron wall bombardment. Electron bombardment can both heat the cold vacuum chamber and induce an increase in the pressure because of gas desorption. In this contribution we compare the measurements of the pressure in a cold bore performed in the electron storage ring ANKA with the predictions obtained using the equations of gas dynamic balance in a cold vacuum chamber exposed to synchrotron radiation and electron bombardment. The balance results from two competing effects: the photon and electron stimulated desorption of the gas contained in the surface layer of the chamber wall and of the gas cryosorbed, and the cryopumping by the cold surface. We show that photodesorption alone cannot explain the experimental results and that electron multipacting is needed to reproduce the observed pressure rise. Electron bombardment can at the same time explain the observed beam heat load.

  16. Earthquake damage to underground facilities

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, H.R.; Hustrulid, W.A. Stephenson, D.E.

    1978-11-01

    The potential seismic risk for an underground nuclear waste repository will be one of the considerations in evaluating its ultimate location. However, the risk to subsurface facilities cannot be judged by applying intensity ratings derived from the surface effects of an earthquake. A literature review and analysis were performed to document the damage and non-damage due to earthquakes to underground facilities. Damage from earthquakes to tunnels, s, and wells and damage (rock bursts) from mining operations were investigated. Damage from documented nuclear events was also included in the study where applicable. There are very few data on damage in the subsurface due to earthquakes. This fact itself attests to the lessened effect of earthquakes in the subsurface because mines exist in areas where strong earthquakes have done extensive surface damage. More damage is reported in shallow tunnels near the surface than in deep mines. In mines and tunnels, large displacements occur primarily along pre-existing faults and fractures or at the surface entrance to these facilities.Data indicate vertical structures such as wells and shafts are less susceptible to damage than surface facilities. More analysis is required before seismic criteria can be formulated for the siting of a nuclear waste repository.

  17. Detonator assembly for oil well perforating gun

    Energy Technology Data Exchange (ETDEWEB)

    Regalbuto, J.A.

    1981-02-18

    A safe/arm detonator assembly for use with an oil well perforating gun assembly has 2 housing members isolated from well-bore fluid which are rotatable from a safe position wherein a detonator and a booster are held out of alignment, to an armed position wherein the detonator and booster are moved into alignment. The detonator assembly is further arranged to be installed in a well perforating gun assembly such that the gun assembly may be transported with the detonator assembly in the safe position, and rotated to the armed position at the well site without disassembling the gun assembly. A safety pin may protrude from one of the housing members across a cavity between the members to cover and protect the booster from accidental detonation when the detonator assembly is in the safe position. The detonator and booster cavities may be held aligned by a detent ball. 16 claims.

  18. 3种李树天牛识别、为害及其综合防控技术措施%Identification and Damages of Three Kinds of Longicorn as well as Their Synthetical Prevention on Plum Trees

    Institute of Scientific and Technical Information of China (English)

    黄鹏; 余德亿; 姚锦爱; 王金明; 方大琳

    2012-01-01

      Longicorn was one of the main pests on plum trees. They occurred seriously in recent years and posed a threat to the healthy planting of plum trees. This paper introduced the identification features and damage characteristics of Anoplophora chinensis, Aromia bungii and Apriona germari, and synthetically discussed their prevention and control measures from the way of agricultural, physical, biological and chemical controls. The objective was to realize the pollution-free and sustainable controls of longicorns on plum trees.%  天牛是李树的主要害虫之一,近年发生较重,对李树健康种植构成威胁。本文介绍星天牛、桃红颈天牛和粒肩天牛等3种李树天牛的识别特征和为害特点,并从农业防治、物理防治、生物防治和化学防治等方面综合探讨其防控技术措施,以期实现对李树天牛的无公害和可持续控制。

  19. 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...

  20. 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.

  1. Study on Influensive Factors on Surface Quality and Edges of Through- Holes Bored in Particleboard and MDF

    Directory of Open Access Journals (Sweden)

    Abolghasem Khazaian

    2012-06-01

    Full Text Available In this research, effects of different factors in the CNC machine through- Hole boring of MDF and particleboard were investigated. Variables in boring were selected bit diameter in 3 levels 5,10 and 15 mm, feed speed in 2 levels 0.3 m/min and 0.6 m/min and rotary speed of machine axis in 3 levels 300,1500 and 3000 rmp. The goal of this study was to measure effects of mentioned factors on edge- quality of through- holes made in particle- board and MDF. Results have shown that with all bit diameters used, increasing rotary speed of bit improves smoothness of holes in both sides and boring dusts turned to finer sizes. Increasing feed speed did show positive effect on edge surface quality and lowered burr formation.

  2. 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.

  3. Irradiation damage

    Energy Technology Data Exchange (ETDEWEB)

    Howe, L.M

    2000-07-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

  4. A multiaxial incremental fatigue damage formulation using nested damage surfaces

    Directory of Open Access Journals (Sweden)

    Marco Antonio Meggiolaro

    2016-07-01

    Full Text Available Multiaxial fatigue damage calculations under non-proportional variable amplitude loadings still remains a quite challenging task in practical applications, in part because most fatigue models require cycle identification and counting to single out individual load events before quantifying the damage induced by them. Moreover, to account for the non-proportionality of the load path of each event, semi-empirical methods are required to calculate path-equivalent ranges, e.g. using a convex enclosure or the MOI (Moment Of Inertia method. In this work, a novel Incremental Fatigue Damage methodology is introduced to continuously account for the accumulation of multiaxial fatigue damage under service loads, without requiring rainflow counters or path-equivalent range estimators. The proposed approach is not based on questionable Continuum Damage Mechanics concepts or on the integration of elastoplastic work. Instead, fatigue damage itself is continuously integrated, based on damage parameters adopted by traditional fatigue models well tested in engineering practice. A framework of nested damage surfaces is introduced, allowing the calculation of fatigue damage even for general 6D multiaxial load histories. The proposed approach is validated by non-proportional tensiontorsion experiments on tubular 316L stainless steel specimens.

  5. 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.

  6. 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.

  7. 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

  8. First record of a pontoniine shrimp (Caridea, Palaemonidae) in association with a boring bivalve of the genus Spengleria (Bivalvia, Euheterodonta, Gastrochaenidae)

    NARCIS (Netherlands)

    Fransen, C.H.J.M.; Meij, van der S.E.T.

    2010-01-01

    During fieldwork in Raja Ampat, West Papua, Indonesia, in 2007, a pontoniine shrimp, most likely belonging to the genus Anchistus, was collected from a coral boring bivalve of the genus Spengleria. This is the first record of a pontoniine shrimp living in association with a boring bivalve. As it pro

  9. A NEW METHOD FOR PREDICTION OF PRODUCTIVITY OF FRACTURED HORIZONTAL WELLS BASED ON NON-STEADY FLOW

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hydraulic fracturing technologies of horizontal well are important ways to develop oil-gas field with low permeability. Productivity forecast of fractured horizontal wells is a difficult problem of hydraulic fracturing technologies. Basing on non-steady flow of fractures fluid during production, applying potential function principles, superposition principle and mathematical method for solving, coupling of seepage flow in the formation and pipe flow in the well bore, a new model on multi-fracture interference productivity forecast of fractured horizontal well is established in this article. The results indicate the coincidence rate between this model and practice is high. The pressure loss in the horizontal well bore has definite influence on the production status of fractured horizontal wells. The productions of different fractures in horizontal well bore are unequal, the productions of outer fractures are higher than middle fractures; the pressure in the well bore shows an uneven distribution, the pressure declines gradually from finger tip to heel end. Asymmetry of fractures may make productivity of fractured horizontal wells decline. The conclusions are instructive in designing fractured horizontal well for low permeability reservoir.

  10. 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.

  11. 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.}

  12. 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.

  13. Hole boring in a DT Pellet and Fast-Ion Ignition with Ultraintense Laser Pulses.

    Science.gov (United States)

    Naumova, N; Schlegel, T; Tikhonchuk, V T; Labaune, C; Sokolov, I V; Mourou, G

    2009-01-16

    Recently achieved high intensities of short laser pulses open new prospects in their application to hole boring in inhomogeneous overdense plasmas and for ignition in precompressed DT fusion targets. A simple analytical model and numerical simulations demonstrate that pulses with intensities exceeding 10;{22} W/cm;{2} may penetrate deeply into the plasma as a result of efficient ponderomotive acceleration of ions in the forward direction. The penetration depth as big as hundreds of microns depends on the laser fluence, which has to exceed a few tens of GJ/cm;{2}. The fast ions, accelerated at the bottom of the channel with an efficiency of more than 20%, show a high directionality and may heat the precompressed target core to fusion conditions.

  14. 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.

  15. 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.

  16. 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.

  17. Talc Pleurodesis Through Very-Small-Bore Catheters in Patients with Recurrent Malignant Pleural Effusion

    Directory of Open Access Journals (Sweden)

    Ali Özgen

    2016-04-01

    Full Text Available Objective: Malignant pleural effusion (MPE is a frequent and disturbing complication of metastatic disease. Talc pleurodesis via percutaneosly placed 12–18F catheters is an effective procedure to treat recurrent MPE. We aimed to determine the efficiency of talc pleurodesis through very-small-bore catheters in the treatment of recurrent malignant pleural effusion. Methods: We performed 13 talc pleurodesis procedures in 10 patients with recurrent MPE via pre-existing 7F (6 patients and 8F (4 patients pig-tail catheters. We analyzed technical and clinical success of the procedure. Results: All procedures were performed successfully. Complete or partial clinical success was achieved in 8 out of 10 patients. No major complication was observed. Conclusion: Talc pleurodesis through 7F or 8F catheters may be performed in selected patients with reduced patient discomfort, and similar success rates that was obtained using higher caliber catheters in the treatment of recurrent MPE.

  18. Biogeography of wood-boring crustaceans (Isopoda: Limnoriidae) established in European coastal waters.

    Science.gov (United States)

    Borges, Luísa M S; Merckelbach, Lucas M; Cragg, Simon M

    2014-01-01

    Marine wood-borers of the Limnoriidae cause great destruction to wooden structures exposed in the marine environment. In this study we collated occurrence data obtained from field surveys, spanning over a period of 10 years, and from an extensive literature review. We aimed to determine which wood-boring limnoriid species are established in European coastal waters; to map their past and recent distribution in Europe in order to infer species range extension or contraction; to determine species environmental requirements using climatic envelopes. Of the six species of wood-boring Limnoria previously reported occurring in Europe, only Limnoria lignorum, L. quadripunctata and L. tripunctata are established in European coastal waters. L. carinata and L. tuberculata have uncertain established status, whereas L. borealis is not established in European waters. The species with the widest distribution in Europe is Limnoria lignorum, which is also the most tolerant species to a range of salinities. L. quadripunctata and L. tripunctata appear to be stenohaline. However, the present study shows that both L. quadripunctata and L. tripunctata are more widespread in Europe than previous reports suggested. Both species have been found occurring in Europe since they were described, and their increased distribution is probably the results of a range expansion. On the other hand L. lignorum appears to be retreating poleward with ocean warming. In certain areas (e.g. southern England, and southern Portugal), limnoriids appear to be very abundant and their activity is rivalling that of teredinids. Therefore, it is important to monitor the distribution and destructive activity of these organisms in Europe.

  19. 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.

  20. Thermal properties of a large-bore cryocooled 10 T superconducting magnet for a hybrid magnet

    Energy Technology Data Exchange (ETDEWEB)

    Ishizuka, M., E-mail: Mas_Ishizuka@shi.co.j [Graduate School of Engineering, Tohoku University, 6-6 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579 (Japan); Research and Development Center, Sumitomo Heavy Industries, Ltd., 19 Natsushima-chou, Yokosuka, Kanagawa 237-8555 (Japan); Hamajima, T. [Graduate School of Engineering, Tohoku University, 6-6 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579 (Japan); Itou, T. [Ehime Works, Sumitomo Heavy Industries, Ltd., 5-2 Soubiraki-cho, Niihama, Ehime 792-8588 (Japan); Sakuraba, J. [Research and Development Center, Sumitomo Heavy Industries, Ltd., 19 Natsushima-chou, Yokosuka, Kanagawa 237-8555 (Japan); Nishijima, G.; Awaji, S.; Watanabe, K. [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2010-11-01

    A cryocooled 10 T superconducting magnet with a 360 mm room temperature bore has been developed for a hybrid magnet. The superconducting magnet cooled by four Gifford-McMahon cryocoolers has been designed to generate a magnetic field of 10 T. Since superconducting wires composed of coils were subjected to large hoop stress over 150 MPa and Nb{sub 3}Sn superconducting wires particularly showed a low mechanical strength due to those brittle property, Nb{sub 3}Sn wires strengthened by NbTi-filaments were developed for the cryocooled superconducting magnet. We have already reported that the hybrid magnet could generate the resultant magnetic field of 27.5 T by adding 8.5 T from the superconducting magnet and 19 T from a water-cooled Bitter resistive magnet, after the water-cooled resistive magnet was inserted into the 360 mm room temperature bore of the cryocooled superconducting magnet. When the hybrid magnet generated the field of 27.5 T, it achieved the high magnetic-force field (B x {partial_derivative}Bz/{partial_derivative}z) of 4500 T{sup 2}/m, which was useful for magneto-science in high fields such as materials levitation research. In this paper, we particularly focus on the cause that the cryocooled superconducting magnet was limited to generate the designed magnetic field of 10 T in the hybrid magnet operation. As a result, it was found that there existed mainly two causes as the limitation of the magnetic field generation. One was a decrease of thermal conductive passes due to exfoliation from the coil bobbin of the cooling flange. The other was large AC loss due to both a thick Nb{sub 3}Sn layer and its large diameter formed on Nb-barrier component in Nb{sub 3}Sn wires.

  1. 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.

  2. 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。

  3. Geothermal Well Stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D. A.; Morris, C. W.; Sinclair, A. R.; Hanold, R. J.; Vetter, O. J.

    1981-03-01

    The stimulation of geothermal wells presents some new and challenging problems. Formation temperatures in the 300-600 F range can be expected. The behavior of stimulation fluids, frac proppants, and equipment at these temperatures in a hostile brine environment must be carefully evaluated before performance expectations can be determined. In order to avoid possible damage to the producing horizon of the formation, high temperature chemical compatibility between the in situ materials and the stimulation materials must be verified. Perhaps most significant of all, in geothermal wells the required techniques must be capable of bringing about the production of very large amounts of fluid. This necessity for high flow rates represents a significant departure from conventional petroleum well stimulation and demands the creation of very high near-wellbore permeability and/or fractures with very high flow conductivity.

  4. 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.

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

    Science.gov (United States)

    Yang, Joyce C; Madupu, Ramana; Durkin, A Scott; Ekborg, Nathan A; Pedamallu, Chandra S; Hostetler, Jessica B; Radune, Diana; Toms, Bradley S; Henrissat, Bernard; Coutinho, Pedro M; Schwarz, Sandra; Field, Lauren; Trindade-Silva, Amaro E; Soares, Carlos A G; Elshahawi, Sherif; Hanora, Amro; Schmidt, Eric W; Haygood, Margo G; Posfai, Janos; Benner, Jack; Madinger, Catherine; Nove, John; Anton, Brian; Chaudhary, Kshitiz; Foster, Jeremy; Holman, Alex; Kumar, Sanjay; Lessard, Philip A; Luyten, Yvette A; Slatko, Barton; Wood, Nicole; Wu, Bo; Teplitski, Max; Mougous, Joseph D; Ward, Naomi; Eisen, Jonathan A; Badger, Jonathan H; Distel, Daniel L

    2009-07-01

    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 of cellulose

  6. 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

  7. Pre-treatment assemblages of wood-boring beetles (Coleoptera: Buprestidae, Cerambycidae) of the hardwood ecosystem experiment

    Science.gov (United States)

    Jeffrey D. Holland; John T. Shukle; Hossam Eldien M. Abdel Moniem; Thomas W. Mager; Kapil R. Raje; Kyle Schnepp; Shulin. Yang

    2013-01-01

    Longhorned beetles are a diverse and important group of insects in forest ecosystems; several species attack weakened or stressed trees, relatively few attack healthy trees, and most species use only dead and decomposing wood. We surveyed longhorned beetles and metallic wood-boring beetles using four different types of traps at 36 Hardwood Ecosystem Experiment (Indiana...

  8. Genome Sequence of Fusarium Isolate MYA-4552 from the Midgut of Anoplophora glabripennis, an Invasive, Wood-Boring Beetle.

    Science.gov (United States)

    Herr, Joshua R; Scully, Erin D; Geib, Scott M; Hoover, Kelli; Carlson, John E; Geiser, David M

    2016-07-21

    The Fusarium solani species complex (FSSC) is a clade of environmentally ubiquitous fungi that includes plant, animal, and insect associates. Here, we report the draft genome sequence of the undescribed species FSSC 6 (isolate MYA-4552), housed in the gut of the wood-boring cerambycid beetle Anoplophora glabripennis.

  9. Genome sequence of Fusarium isolate MYA-4552 from the midgut of Anoplophora glabripennis, an invasive, wood-boring beetle

    Science.gov (United States)

    The Fusarium solani species complex (FSSC) is a clade of environmentally ubiquitous fungi that includes plant, animal and insect associates. Here we report the draft genome sequence of the undescribed species FSSC 6 (isolate MYA-4552), housed in the gut of the wood-boring cerambycid beetle Anoplopho...

  10. 7 CFR 51.2655 - Damage.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Damage. 51.2655 Section 51.2655 Agriculture... Standards for Grades for Sweet Cherries 1 Definitions § 51.2655 Damage. Damage means any specific defect... appearance; (c) Hail injury when deep or not well healed, or when the aggregate area exceeds the area of...

  11. 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

    2017-04-01

    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.

  12. How expensive is vole damage?

    OpenAIRE

    Walther, B; Fülling, O.; Malevez, J.; Pelz, H.-J.

    2008-01-01

    Vole species, especially Arvicola terrestris and Microtus arvalis cause significant economical damage in organic pomiculture by gnawing the root system of trees. The importance of voles as pest organisms is well known. Nevertheless, the estimation of financial loss caused by voles is difficult for German fruit growers. We conducted a survey among organic fruit growers to get data on kind and amount of annual damage. Using the available publications and official statistics we calculated econom...

  13. An Ultra-High Field Strength MR Image-Guided Robotic Needle Delivery System for In-Bore Small Animal Interventions.

    Science.gov (United States)

    Gravett, Matthew; Cepek, Jeremy; Fenster, Aaron

    2017-08-28

    To develop and validate an image-guided robotic needle delivery system for accurate and repeatable needle targeting procedures in mouse brains inside the 12cm inner diameter gradient coil insert of a 9.4T MR scanner. Many preclinical research techniques require the use of accurate needle deliveries to soft tissues, including brain tissue. Soft tissues are optimally visualized in MR images, which offer high-soft tissue contrast, as well as a range of unique imaging techniques, including functional, spectroscopy and thermal imaging, however, there are currently no solutions for delivering needles to small animal brains inside the bore of an ultra-high field MR scanner. This paper describes the mechatronic design, evaluation of MR compatibility, registration technique, mechanical calibration, the quantitative validation of the in-bore image-guided needle targeting accuracy and repeatability, and demonstrated the system's ability to deliver needles in-situ. Our six degree-of-freedom, MR compatible, mechatronic system was designed to fit inside the bore of a 9.4T MR scanner and is actuated using a combination of piezoelectric and hydraulic mechanisms. The MR compatibility and targeting accuracy of the needle delivery system are evaluated to ensure that the system is precisely calibrated to perform the needle targeting procedures. A semi-automated image registration is performed to link the robot coordinates to the MR coordinate system. Soft tissue targets can be accurately localized in MR images, followed by automatic alignment of the needle trajectory to the target. Intra-procedure visualization of the needle target location and the needle were confirmed through MR images after needle insertion. The effects of geometric distortions and signal noise were found to be below threshold that would have an impact on the accuracy of the system. The system was found to have negligible effect on the MR image signal noise and geometric distortion. The system was mechanically

  14. Single well tracer method to evaluate enhanced recovery

    Science.gov (United States)

    Sheely, Jr., Clyde Q.; Baldwin, Jr., David E.

    1978-01-01

    Data useful to evaluate the effectiveness of or to design an enhanced recovery process (the recovery process involving mobilizing and moving hydrocarbons through a hydrocarbon-bearing subterranean formation from an injection well to a production well by injecting a mobilizing fluid into the injection well) are obtained by a process which comprises sequentially: determining hydrocarbon saturation in the formation in a volume in the formation near a well bore penetrating the formation, injecting sufficient of the mobilizing fluid to mobilize and move hydrocarbons from a volume in the formation near the well bore penetrating the formation, and determining by the single well tracer method a hydrocarbon saturation profile in a volume from which hydrocarbons are moved. The single well tracer method employed is disclosed by U.S. Pat. No. 3,623,842. The process is useful to evaluate surfactant floods, water floods, polymer floods, CO.sub.2 floods, caustic floods, micellar floods, and the like in the reservoir in much less time at greatly reduced costs, compared to conventional multi-well pilot test.

  15. 双模式全断面掘进机探讨%Discussion on Dual-mode Full-face Tunnel Boring Machines

    Institute of Scientific and Technical Information of China (English)

    张宁川; 李光

    2013-01-01

    为适应地质的复杂性以及中国国情,探讨双模式全断面掘进机的未来发展趋势,并举例说明双模式全断面掘进机的设计理念,详述其主要结构及适用范围.与单模式掘进机相比,双模式全断面掘进机地质适应性广、设备利用率高、施工成本低,是隧道掘进设备技术发展的主要方向之一,具有良好的发展前景.%The development trend of dual-mode full-face tunnel boring machines is discussed,the design concept of dual-mode full-face tunnel boring machines is presented and the main structure and applicability scope of dual-mode fullface tunnel boring machines are described in detail.The study shows that,compared to single-mode tunnel boring machines,the applicability scope of dual-mode full-face tunnel boring machines is more extensive,the availability of dualmode full-face tunnel boring machines is higher and the tunneling cost of dual-mode full-face tunnel boring machines is lower.Conclusion is drawn that the dual-mode full-face tunnel boring machine,which is the main development trend of tunnel boring machines,has a splendid future.

  16. Avoidance of unconventional oil wells and roads exacerbates habitat loss for grassland birds in the North American great plains

    Science.gov (United States)

    Thompson, Sarah J.; Johnson, Douglas H.; Nieumuth, Neal; Ribic, Christine

    2015-01-01

    Oil development in the Bakken shale region has increased rapidly as a result of new technologies and strong demand for fossil fuel. This region also supports a particularly high density and diversity of grassland bird species, which are declining across North America. We examined grassland bird response to unconventional oil extraction sites (i.e. developed with hydraulic fracturing and horizontal drilling techniques) and associated roads in North Dakota. Our goal was to quantify the amount of habitat that was indirectly degraded by oil development, as evidenced by patterns of avoidance by birds. Grassland birds avoided areas within 150 m of roads (95% CI: 87–214 m), 267 m of single-bore well pads (95% CI: 157–378 m), and 150 m of multi-bore well pads (95% CI: 67–233 m). Individual species demonstrated variable tolerance of well pads. Clay-colored sparrows (Spizella pallida) were tolerant of oil-related infrastructure, whereas Sprague's pipit (Anthus spragueii) avoided areas within 350 m (95% CI: 215–485 m) of single-bore well pads. Given these density patterns around oil wells, the potential footprint of any individual oil well, and oil development across the region, is greatly multiplied for sensitive species. Efforts to reduce new road construction, concentrate wells along developed corridors, combine numerous wells on multi-bore pads rather than build many single-bore wells, and to place well pads near existing roads will serve to minimize loss of suitable habitat for birds. Quantifying environmental degradation caused by oil development is a critical step in understanding how to better mitigate harm to wildlife populations.

  17. 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

    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...Laboratory’s (ARL’s) Rectangular 22- × 44-mm In-bore Cross Section Railgun Miguel A. Del Güercio and Alexander Michlin Weapons and Materials Research...bore Cross Section Railgun 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Miguel A. Del Güercio and Alexander

  18. Wushuihe Bridge Large Diameter Bored Pile Construction in Water%舞水河大桥水中大直径钻孔桩施工

    Institute of Scientific and Technical Information of China (English)

    张维远

    2015-01-01

    This article introduced the construction process of the large diameter bored pile of Wushuige Bridge, summarized the construction technology of large diameter bored pile, and discussed the troubleshooting process for bored pile construction.%本文通过舞水河特大桥大口径钻孔桩的施工过程的介绍,对大口径钻孔桩的施工工艺进行了总结,并对钻孔桩施工过程的故障处理进行了探讨。

  19. 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.

  20. 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.

  1. Supersonic Virtual Valve Design for Numerical Simulation of a Large-Bore Natural Gas Engine

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G.-H.; Kirkpatrick, A.; Mitchell, C.

    2007-10-01

    In many applications of supersonic injection devices, three-dimensional computation that can model a complex supersonic jet has become critical. However, in spite of its increasing necessity, it is computationally costly to capture the details of supersonic structures in intricate three-dimensional geometries with moving boundaries. In large-bore stationary natural gas fueled engine research, one of the most promising mixing enhancement technologies currently used for natural gas engines is high-pressure fuel injection. Consequently, this creates considerable interest in three-dimensional computational simulations that can examine the entire injection and mixing process in engines using high-pressure injection and can determine the impact of injector design on engine performance. However, the cost of three-dimensional engine simulations-including a moving piston and the kinetics of combustion and pollutant production quickly becomes considerable in terms of simulation time requirements. One limiting factor is the modeling of the small length scales of the poppet valve flow. Such length scales can be three orders of magnitude smaller than cylinder length scales. The objective of this paper is to describe the development of a methodology for the design of a simple geometry supersonic virtual valve that can be substituted in three-dimensional numerical models for the complex shrouded poppet valve injection system actually installed in the engine to be simulated.

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

    CERN Multimedia

    CERN PhotoLab

    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...

  3. 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.

  4. 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.

  5. Incidence of bark- and wood-boring insects in firewood: a survey at Michigan's Mackinac Bridge.

    Science.gov (United States)

    Haack, Robert A; Petrice, Toby R; Wiedenhoeft, Alex C

    2010-10-01

    Firewood is a major pathway for the inadvertent movement of bark- and wood-infesting insects. After discovery of Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in southeastern Michigan in 2002, quarantines were enacted including prohibition of transporting firewood across the Mackinac Bridge between Michigan's Lower and Upper peninsulas. Drivers are required to surrender firewood before crossing the bridge. We surveyed recently surrendered firewood in April, July, and September 2008 and categorized it by genus, cross-sectional shape (whole, half, or quarter), approximate age (years since it was a live tree), presence of bark, and evidence of bark- and wood-boring insects. The 1045 pieces of firewood examined represented 21 tree genera: primarily Acer (30%), Quercus (18%), Fraxinus (15%), Ulmus (12%), Betula (5%), and Prunus (5%). Live borers (Bostrichoidea, Brentidae, Buprestidae, Cerambycidae, Cossidae, Curculionidae [Scolytinae and non-Scolytinae], and Siricidae) were found in 23% of the pieces and another 41% had evidence of previous borer infestation. Of the 152 Fraxinus firewood pieces, 13% had evidence of past A. planipennis infestation, but we found no live A. planipennis. We discuss national "don't move firewood" campaigns and U.S. imports of fuelwood. During 1996-2009, the United States imported fuelwood valued at > dollars U.S. 98 million from 34 countries.

  6. YUCCA MOUNTAIN SITE CHARACTERIZATIONS PROJECT TUNNEL BORING MACHINE (TBM) SYSTEM SAFETY ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1997-02-19

    The purpose of this analysis is to systematically identify and evaluate hazards related to the tunnel boring machine (TBM) used in the Exploratory Studies Facility (ESF) at the Yucca Mountain Site Characterization Project. This process is an integral part of the systems engineering process; whereby safety is considered during planning, design, testing, and construction. Since the TBM is an ''as built'' system, the M&O is conducting the System Safety Analysis during the construction or assembly phase of the TBM. A largely qualitative approach was used since a radiological System Safety Analysis is not required. The risk assessment in this analysis characterizes the accident scenarios associated with the TBM in terms of relative risk and includes recommendations for mitigating all identified risks. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures to reduce risks and hazards into the system/subsystem/component design, (2) add safety features and capabilities to existing designs, and (3) develop procedures and conduct training to increase worker awareness of potential hazards, on methods to reduce exposure to hazards, and on the actions required to avoid accidents or correct hazardous conditions. The scope of this analysis is limited to the TBM during normal operations, excluding hazards occurring during assembly and test of the TBM or maintenance of the TBM equipment.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Hard rock tunnel boring machine penetration test as an indicator of chipping process efficiency

    Directory of Open Access Journals (Sweden)

    M.C. Villeneuve

    2017-08-01

    Full Text Available The transition from grinding to chipping can be observed in tunnel boring machine (TBM penetration test data by plotting the penetration rate (distance/revolution against the net cutter thrust (force per cutter over the full range of penetration rates in the test. Correlating penetration test data to the geological and geomechanical characteristics of rock masses through which a penetration test is conducted provides the ability to reveal the efficiency of the chipping process in response to changing geological conditions. Penetration test data can also be used to identify stress-induced tunnel face instability. This research shows that the strength of the rock is an important parameter for controlling how much net cutter thrust is required to transition from grinding to chipping. It also shows that the geological characteristics of a rock will determine how efficient chipping occurs once it has begun. In particular, geological characteristics that lead to efficient fracture propagation, such as fabric and mica contents, will lead to efficient chipping. These findings will enable a better correlation between TBM performance and geological conditions for use in TBM design, as a basis for contractual payments where penetration rate dominates the excavation cycle and in further academic investigations into the TBM excavation process.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. "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.

  1. 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

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

    Science.gov (United States)

    Kendra, Paul E; Montgomery, Wayne S; Niogret, Jerome; Pruett, Grechen E; Mayfield, Albert E; MacKenzie, Martin; Deyrup, Mark A; Bauchan, Gary R; Ploetz, Randy C; Epsky, Nancy D

    2014-01-01

    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 calamenene were

  3. Study on Machining Properties of Eucalyptus urophylla×E.grandis:Ⅱ.Shaping, Boring, Mortising and Turning

    Institute of Scientific and Technical Information of China (English)

    HOU Xinyi; JIANG Xiaomei; GAO Jianmin; YIN Yafang

    2006-01-01

    The research method of this paper is based on the standards of American Society for Testing and Materials(ASTM).Four items that contain boring,mortising,shaping and turning are selected to study the machining properties of E. urophylla×E. grandis plantation wood.The reasons for machining defects are analyzed.The result shows that E.urophylla×E.grandis planted in South China is a good species with great potential for solid wood utilization.

  4. 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.

  5. 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.

  6. Fine-structural analysis of black band disease-infected coral reveals boring cyanobacteria and novel bacteria.

    Science.gov (United States)

    Miller, Aaron W; Blackwelder, Patricia; Al-Sayegh, Husain; Richardson, Laurie L

    2011-02-22

    Examination of coral fragments infected with black band disease (BBD) at the fine- and ultrastructural levels using scanning (SEM) and transmission electron microscopy (TEM) revealed novel features of the disease. SEM images of the skeleton from the host coral investigated (Montastraea annularis species complex) revealed extensive boring underneath the BBD mat, with cyanobacterial filaments present within some of the bore holes. Cyanobacteria were observed to penetrate into the overlying coral tissue from within the skeleton and were present throughout the mesoglea between tissue layers (coral epidermis and gastrodermis). A population of novel, as yet unidentified, small filamentous bacteria was found at the leading edge of the migrating band. This population increased in number within the band and was present within degrading coral epithelium, suggesting a role in disease etiology. In coral tissue in front of the leading edge of the band, cyanobacterial filaments were observed to be emerging from bundles of sloughed-off epidermal tissue. Degraded gastrodermis that contained actively dividing zooxanthellae was observed using both TEM and SEM. The BBD mat contained cyanobacterial filaments that were twisted, characteristic of negative-tactic responses. Some evidence of boring was found in apparently healthy control coral fragments; however, unlike in BBD-infected fragments, there were no associated cyanobacteria. These results suggest the coral skeleton as a possible source of pathogenic BBD cyanobacteria. Additionally, SEM revealed the presence of a potentially important group of small, filamentous BBD-associated bacteria yet to be identified.

  7. 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.

  8. 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.

  9. 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.

  10. Pressure Buildup Analysis for Two-Phase Geothermal Wells: Application to the Baca Geothermal Field

    Science.gov (United States)

    Riney, T. D.; Garg, S. K.

    1985-03-01

    The recently published pressure transient analysis methods for two-phase geothermal wells are employed to analyze the pressure buildup data for several wells located in the Redondo Creek area of the Baca geothermal field in New Mexico. The downhole drilling information and pressure/temperature surveys are first interpreted to locate zones at which fluid enters the well bore from the formation and to estimate the initial reservoir temperature and pressure in these zones. All of the Baca wells considered here induced flashing in the formation upon production. Interpretation of the buildup data for each well considers well bore effects (e.g., phase change in the well bore fluid and location of the pressure sensor with respect to the permeable horizon) and the carbon dioxide content of the fluid and its effects on the phase behavior of the reservoir fluids and differentiates between the single- and two-phase portions of the pressure buildup data. Different straight-line approximations to the two portions (i.e., single- and two-phase) of the data on the Homer plot are used to obtain corresponding estimates for the single- and two-phase mobilities. Estimates for the formation permeability-thickness (kH) product are also given.

  11. 钻孔灌注桩施工中的质量通病及预防%Quality diseases and prevention of bored pile in construction

    Institute of Scientific and Technical Information of China (English)

    魏银玲

    2014-01-01

    The paper briefly discribes the characteristics of bored pile,analyzes bored pile construction quality problems causes such as hole-wall cracks,pile broken,bored pile inclination and shrinkage and so on,and puts forward preventive measures,with a view to reduce construction quality diseases and to further improve bored pile construction quality.%简述了钻孔灌注桩的特性,对钻孔灌注桩施工中容易出现的孔壁塌孔、断桩、钻孔倾斜、缩孔等质量问题成因进行了分析,并提出了预防措施,以期将施工质量病害的发生率降至最低,进一步提高钻孔灌注桩的质量。

  12. Desin and application of a new type of boring cutter head%一种新型镗刀头的设计与应用

    Institute of Scientific and Technical Information of China (English)

    林景凡

    2013-01-01

    Basis of comparison in two kinds of boring cutter structure and processing characteristics.The machine clamp in large diameter deep hole boring processing technology of single blade. Can replace the commonly used strong rough boring, boring, floating cutter honing processes three, can make the work efficiency is improved by more than 3 times.%在两种镗刀结构和加工特点比较的基础上,介绍了机夹单刃镗刀加工大直径深孔工艺。可取代通常使用的强力粗镗、浮动刀精镗、珩磨三道工序,可使工效提高3倍以上。

  13. The Construction Technologies and Quality Control Measures of Rotary Drilling Bored Piles%旋挖桩的施工工艺及质量保证措施

    Institute of Scientific and Technical Information of China (English)

    孙晓元

    2015-01-01

    ABSTRACT:The construction of rotary drilling bored piles is more advanced way of pile foundation construction, and the rotary drilling bored pile has the the characteristics of good quality and high construction efficiency. This paper introduces in detail the construction technologies of rotary drilling bored pile, and probes into the quality control measures for the construction of rotary drilling bored piles.%旋挖桩施工是现今我国建筑施工中一种较为先进的桩基施工方式,具有质量好、施工效率高的特点。详细介绍了旋挖桩的施工工艺,探讨了旋挖桩的工程质量保证措施。

  14. Molecular phylogeny and shell microstructure of Fungiacava eilatensis Goreau et al. 1968, boring into mushroom corals (Scleractinia: Fungiidae), in relation to other mussels (Bivalvia: Mytilidae)

    NARCIS (Netherlands)

    Owada, M.; Hoeksema, B.W.

    2011-01-01

    Research on the evolution of the symbiosis between the boring mussel Fungiacava eilatensis (Bivalvia: Mytilidae) and its mushroom coral hosts (Scleractinia: Fungiidae), which requires phylogenetic reconstructions of both the Mytilidae and the Fungiidae, contributes to the understanding of the comple

  15. On the selection of equipment combination and craft in bored pile%钻孔灌注桩机具组合和工艺选择

    Institute of Scientific and Technical Information of China (English)

    赵修健

    2009-01-01

    By combining with the extensive application of the bored pile in the construction, the paper introduces the poring method of the bored pile in the embedded holes and the selection of equipment in soft soil region, explores the craft process of the bored pile and its construetion points, and points out the control strategy of the common problems in quality, so as to accumulate experience for the bored pries.%结合钻孔灌注桩在工程中的广泛应用,介绍了软土地区嵌岩钻孔灌注桩成孔方法和设备的选择,探讨了钻孔灌注桩工艺流程及施工要点,提出了质量通病的控制对策,积累了钻孔灌注桩的施工经验.

  16. Impact of passing mesenchymal stem cells through smaller bore size needles for subsequent use in patients for clinical or cosmetic indications

    National Research Council Canada - National Science Library

    Mamidi, Murali Krishna; Singh, Gurbind; Husin, Juani Mazmin; Nathan, Kavitha Ganesan; Sasidharan, Gopinath; Zakaria, Zubaidah; Bhonde, Ramesh; Majumdar, Anish Sen; Das, Anjan Kumar

    2012-01-01

    .... In this report, we aimed to investigate the smallest possible bore size needle which would support the safe delivery of MSCs into various tissues for different clinical or cosmetic applications...

  17. Aldosterone and vascular damage.

    Science.gov (United States)

    Duprez, D; De Buyzere, M; Rietzschel, E R; Clement, D L

    2000-06-01

    Although the aldosterone escape mechanism is well known, aldosterone has often been neglected in the pathophysiologic consequences of the activated renin-angiotensin-aldosterone system in arterial hypertension and chronic heart failure. There is now evidence for vascular synthesis of aldosterone aside from its secretion by the adrenal cortex. Moreover, aldosterone is involved in vascular smooth muscle cell hypertrophy and hyperplasia, as well as in vascular matrix impairment and endothelial dysfunction. The mechanisms of action of aldosterone may be either delayed (genomic) or rapid (nongenomic). Deleterious effects of aldosterone leading to vascular target-organ damage include (besides salt and water retention) decreased arterial and venous compliance, increased peripheral vascular resistance, and impaired autonomic vascular control due to baroreflex dysfunction.

  18. REDUCTION OF AN ADVERSE IMPACT DURING WELL DRILLING BY MEANS OF DRILLING WASTE USAGE

    OpenAIRE

    Vladimir Sergeevich Kuznetsov; Igor Konstantinovich Suprun

    2017-01-01

    The problem of drilling waste utilisation is assumed to be resolved through the implementation of the complex of environment protection production engineering measures. This includes, firstly, the usage in the process of well drilling of drilling mud on the basis of water-soluble biodegradable polymers and a four-stage drilling mud refining system. Secondly, the usage of the well site construction with trenching for allocation of expressed bore mud and a temporary ground tank for drilling was...

  19. REDUCTION OF AN ADVERSE IMPACT DURING WELL DRILLING BY MEANS OF DRILLING WASTE USAGE

    Directory of Open Access Journals (Sweden)

    Vladimir Sergeevich Kuznetsov

    2017-03-01

    Full Text Available The problem of drilling waste utilisation is assumed to be resolved through the implementation of the complex of environment protection production engineering measures. This includes, firstly, the usage in the process of well drilling of drilling mud on the basis of water-soluble biodegradable polymers and a four-stage drilling mud refining system. Secondly, the usage of the well site construction with trenching for allocation of expressed bore mud and a temporary ground tank for drilling waste water.

  20. 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.

  1. Development of a Single-Borehole Radar for Well Logging

    Directory of Open Access Journals (Sweden)

    Zheng-ou Zhou

    2012-12-01

    Full Text Available An impulse-based single-borehole radar prototype has been developed for well logging. The borehole radar is comprised of subsurface sonde and surface equipment. An armored 7-conductor well logging cable is used to connect subsurface sonde and surface equipment which is well compatible with the other well logging instruments. The performance experiments of the prototype have been conducted in a test field. The results show that the prototype system is capable of detecting the target which is 8 meters away from the borehole. This radar prototype has been employed in a real oil field well with a depth of about 1600 meters. Compared with conventional resistivity well logging tools, the prototype system provides comprehensive well-bore formation analysis information.  

  2. Mechanism of DNA damage tolerance

    Institute of Scientific and Technical Information of China (English)

    Xin; Bi

    2015-01-01

    DNA damage may compromise genome integrity and lead to cell death. Cells have evolved a variety of processes to respond to DNA damage including damage repair and tolerance mechanisms, as well as damage checkpoints. The DNA damage tolerance(DDT) pathway promotes the bypass of single-stranded DNA lesions encountered by DNA polymerases during DNA replication. This prevents the stalling of DNA replication. Two mechanistically distinct DDT branches have been characterized. One is translesion synthesis(TLS) in which a replicative DNA polymerase is temporarily replaced by a specialized TLS polymerase that has the ability to replicate across DNA lesions. TLS is mechanistically simple and straightforward, but it is intrinsically error-prone. The other is the error-free template switching(TS) mechanism in which the stalled nascent strand switches from the damaged template to the undamaged newly synthesized sister strand for extension past the lesion. Error-free TS is a complex but preferable process for bypassing DNA lesions. However, our current understanding of this pathway is sketchy. An increasing number of factors are being found to participate or regulate this important mechanism, which is the focus of this editorial.

  3. Flood damage modelling: ambition and reality

    Science.gov (United States)

    Gerl, Tina; Kreibich, Heidi; Franco, Guillermo; Marechal, David; Schröter, Kai

    2015-04-01

    Flood damage modelling is of increasing importance for reliable risk assessment and management. Research efforts have improved the understanding of damaging processes and more sophisticated flood damage models have been developed. However, research seems to focus on a limited number of sectors and regions and validation of models still receives too little attention. We present a global inventory of flood damage models which is compiled from a review of scientific papers and research reports on flood damage models. The models are catalogued according to model specifications, geographical characteristics, sectors addressed, input variables used, model validation, transferability and model functions. The inventory is evaluated to position the current state of science and technology in flood damage modelling as well as to derive requirements for benchmarking damage models.

  4. 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.

  5. Ancient origin of endemic Iberian earth-boring dung beetles (Geotrupidae).

    Science.gov (United States)

    Cunha, Regina L; Verdú, José R; Lobo, Jorge M; Zardoya, Rafael

    2011-06-01

    The earth-boring dung beetles belong to the family Geotrupidae that includes more than 350 species classified into three subfamilies Geotrupinae, Lethrinae, and Taurocerastinae, mainly distributed across temperate regions. Phylogenetic relationships within the family are based exclusively on morphology and remain controversial. In the Iberian Peninsula there are 33 species, 20 of them endemic, which suggests that these lineages might have experienced a radiation event. The evolution of morphological adaptations to the Iberian semi-arid environments such as the loss of wings (apterism) or the ability to exploit alternative food resources is thought to have promoted diversification. Here, we present a phylogenetic analysis of 31 species of Geotrupidae, 17 endemic to the Iberian Peninsula, and the remaining from southeastern Europe, Morocco, and Austral South America based on partial mitochondrial and nuclear gene sequence data. The reconstructed maximum likelihood and Bayesian inference phylogenies recovered Geotrupinae and Lethrinae as sister groups to the exclusion of Taurocerastinae. Monophyly of the analyzed geotrupid genera was supported but phylogenetic relationships among genera were poorly resolved. Ancestral character-state reconstruction of wing loss evolution, dating, and diversification tests altogether showed neither evidence of a burst of cladogenesis of the Iberian Peninsula group nor an association between apterism and higher diversification rates. Loss of flight did not accelerate speciation rates but it was likely responsible for the high levels of endemism of Iberian geotrupids by preventing their expansion to central Europe. These Iberian flightless beetle lineages are probably paleoendemics that have survived since the Tertiary in this refuge area during Plio-Pleistocene climatic fluctuations by evolving adaptations to arid and semi-arid environments.

  6. 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.

  7. Damage Atlas for Photographic materials

    Directory of Open Access Journals (Sweden)

    Kristel Van Camp

    2010-11-01

    Full Text Available La conservation des documents photographiques peut nécessiter des interventions préventives ou curatives. Ce choix est guidé par leur état de conservation. Une meilleure connaissance des détériorations est donc cruciale. Le répertoire présenté ici essaie de les classifier selon des caractéristiques spécifiques et leur niveau de gravité. Les différents types de dégradation sont illustrés et décrits avec une terminologie précise. L’auteur propose en regard de ceux-ci l’intervention qui semble la plus appropriée. Ce répertoire s’adresse à toutes les personnes concernées par la photographie, qu’ils soient dans le milieu de la conservation ou dans le domaine artistique, dans les musées ou dans les archives. In order to rescue a damaged photographic object, preventive or conservative actions are needed. Knowing the specific characteristics of different types of damage is crucial. A damage atlas can provide these characteristics. With this atlas the damage can be recognised and appropriate actions can be taken. This damage atlas offers a first attempt to such a characterisation in the field of photography. The damage atlas contains images and the necessary information about damage on photographic material. The atlas with special annotations about the terminology and the grade of the damage is meant for everybody who works with photographic material, as well in museums as in archives.

  8. Compensation for oil pollution damage

    Science.gov (United States)

    Matugina, E. G.; Glyzina, T. S.; Kolbysheva, Yu V.; Klyuchnikov, A. S.; Vusovich, O. V.

    2015-11-01

    The commitment of national industries to traditional energy sources, as well as constantly growing energy demand combined with adverse environmental impact of petroleum production and transportation urge to establish and maintain an appropriate legal and administrative framework for oil pollution damage compensation. The article considers management strategies for petroleum companies that embrace not only production benefits but also environmental issues.

  9. Compensation for oil pollution damage

    OpenAIRE

    Matyugina, Eleonora Grigorievna; Glyzina, Tatiana Svyatoslavovna; Kolbysheva, Yuliya Vladimirovna; Klyuchnikov, A. S.; O. V. Vusovich

    2015-01-01

    The commitment of national industries to traditional energy sources, as well as constantly growing energy demand combined with adverse environmental impact of petroleum production and transportation urge to establish and maintain an appropriate legal and administrative framework for oil pollution damage compensation. The article considers management strategies for petroleum companies that embrace not only production benefits but also environmental issues.

  10. GENERAL EXPRESSIONS OF CONSTITUTIVE EQUATIONS FOR ISOTROPIC ELASTIC DAMAGED MATERIALS

    Institute of Scientific and Technical Information of China (English)

    唐雪松; 蒋持平; 郑健龙

    2001-01-01

    The general expressions of constitutive equations for isotropic elastic damaged materials were derived directly from the basic law of irreversible thermodynamics. The limitations of the classical damage constitutive equation based on the well-known strain equivalence hypothesis were overcome. The relationships between the two elastic isotropic damage models(i. e. single and double scalar damage models)were revealed. When a single scalar damage variable defined according to the microscopic geometry of a damaged material is used to describle the isotropic damage state, the constitutive equations contain two "damage effect functions", which describe the different influences of damage on the two independent elastic constants. The classical damage constitutive equation based on the strain equivalence hypothesis is only the first-order approximation of the general expression.It may be unduly simplified and may fail to describe satisfactorily the damage phenomena of practical materials.

  11. A new method for treating wells in reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gessel, G.M.; Hales, H.B.; Baxter, L.L. [Brigham Young Univ., Provo, UT (United States)

    2007-07-01

    A method of formulating finite difference equations for reservoir models and the singularities around wells was presented. The method incorporated approximate analytical expressions for pressure into a simulation tool's finite difference equations. The method was based on a Peaceman correction used to calculate well bore pressures. The method adopted finite difference equations based on the physics of the flow around the well, and used expressions for the pressure derivatives consistent with the theoretical pressure profiles around straight line wells in an infinite system. The finite difference equations included linear terms and quadratic terms but did not increase the number of pressure points and did not alter the complexity of the resulting linear algebra. Results showed that the pressure equation was accurate for bulk of the reservoir, and also accurately represented the near singularities around the wells. It was concluded that the method accurately represented near singularities in pressures that occur around wellbores. 10 refs., 4 figs.

  12. 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

  13. 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

  14. 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

  15. 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

  16. Fouling and Boring of Glass Reinforced Plastic - Balsa Blocks in a Tropical Marine Environment,

    Science.gov (United States)

    1983-03-01

    Marshall + + Tbrahim 2]) SausItora ? globosa (Sivickis) + + Bankia fimbziatula moll a Roch + + TOTAL 3 2 7 4 Table 6 litent of borer damage (mean ± s.d.) to...Research Centre, Kuala Lumpur, Malaysia Exchange Section, British Library, U.K. Periodicals Recording Section, Science Reference Library, British

  17. Remote detection of forest damage

    Science.gov (United States)

    Rock, B. N.; Vogelmann, J. E.; Vogelmann, A. F.; Hoshizaki, T.; Williams, D. L.

    1986-01-01

    The use of remote sensing to discriminate, measure, and map forest damage is evaluated. TM spectal coverage, a helicopter-mounted radiometer, and ground-based surveys were utilized to examine the responses of the spruces and firs of Camels Hump Mountain, Vermont to stresses, such as pollution and trace metals. The basic spectral properties of vegetation are described. Forest damage at the site was estimated as 11.8-76.0 percent for the spruces and 19-43.8 percent for the balsam firs. Shifts in the spectra of the conifers in particular in the near IR region are analyzed, and variations in the mesophyll cell anatomy and pigment content of the spruces and firs are investigated. The relations between canopy moisture and damage is studied. The TM data are compared to aircraft data and found to be well correlated.

  18. Probabilistic Damage Stability Calculations for Ships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    1996-01-01

    The aim of these notes is to provide background material for the present probabilistic damage stability rules fro dry cargo ships.The formulas for the damage statistics are derived and shortcomings as well as possible improvements are discussed. The advantage of the definiton of fictitious...

  19. Environmental damage in the General Environmental Law

    Directory of Open Access Journals (Sweden)

    Ivan K. Lanegra Quispe

    2013-12-01

    Full Text Available This paper looks at environmental damage definition stipulated by Peruvian General Environmental Law as well as its implications for the environmental policy development. It also outlines complexities involved identifying environmental damage as much as designing and implementing public policies according to Peruvian legislation processing.

  20. 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.

  1. Strong genetic population structure in the boring giant clam, Tridacna crocea, across the Indo-Malay Archipelago: implications related to evolutionary processes and connectivity.

    Science.gov (United States)

    Kochzius, Marc; Nuryanto, Agus

    2008-09-01

    Even though the Indo-Malay Archipelago hosts the world's greatest diversity of marine species, studies on the genetic population structure and gene flow of marine organisms within this area are rather rare. Consequently, not much is known about connectivity of marine populations in the Indo-Malay Archipelago, despite the fact that such information is important to understand evolutionary and ecological processes in the centre of marine biodiversity. This study aims to investigate the genetic population structure of the boring giant clam, Tridacna crocea. The analysis is based on a 456-bp fragment of the cytochrome oxidase I gene from 300 individuals collected from 15 localities across the Indo-Malay Archipelago. Tridacna crocea shows a very strong genetic population structure and isolation by distance, indicating restricted gene flow between almost all sample sites. The observed Phi(ST)-value of 0.28 is very high compared to other studies on giant clams. According to the pronounced genetic differences, the sample sites can be divided into four groups from West to East: (i) Eastern Indian Ocean, (ii) Java Sea, (iii) South China Sea, Indonesian throughflow, as well as seas in the East of Sulawesi, and (iv) Western Pacific. This complex genetic population structure and pattern of connectivity, characterised by restricted gene flow between some sites and panmixing between others can be attributed to the geological history and prevailing current regimes in the Indo-Malay Archipelago.

  2. 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.

  3. Identification of anthocyanins in berries by narrow-bore high-performance liquid chromatography with electrospray ionization detection.

    Science.gov (United States)

    Dugo, P; Mondello, L; Errante, G; Zappia, G; Dugo, G

    2001-08-01

    Qualitative determination of anthocyanins in extracts of red fruits by narrow-bore HPLC/ESI-MS was carried out. This method was used to investigate anthocyanin contents of black bilberry (Vaccinium myrtillus L.), blackberry (Rubus sp.), and mulberry (Morus nigra). An ultraviolet diode array and a mass spectrometer with ESI source were used for detection. Anthocyanin identifications were made by using retention time data and UV-vis and mass spectra and comparing them with those of commercially available standard compounds. The method allowed the identification of fourteen anthocyanins in black bilberry extract, six anthocyanins in blackberry extract, and five anthocyanins in mulberry extract.

  4. Larvae of Lutrochus germari (Lutrochidae: Coleoptera and Stegoelmis sp. (Elmidae: Coleoptera: bore submerged woody debris in Neotropical streams

    Directory of Open Access Journals (Sweden)

    Francisco Valente-Neto

    2011-10-01

    Full Text Available We report boring activity of larval Lutrochus germari Grouvelle, 1889 and Stegoelmis sp. in submerged woody debris and describe the resulting grooves and faecal pellet production. This ability of the larvae was shown by three types of evidence: 1 examination of collected woody debris, 2 rearing of larvae and 3 gut content analysis. The larvae excavated galleries deep into the submerged woody debris. This is the first record of gallery-forming behaviour in submerged woody debris by aquatic beetles, adding larval Lutrochus germari and Stegoelmis sp. to the list of borers in Neotropical aquatic systems.

  5. 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.

  6. 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

  7. 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...

  8. Flood damage curves for consistent global risk assessments

    Science.gov (United States)

    de Moel, Hans; Huizinga, Jan; Szewczyk, Wojtek

    2016-04-01

    Assessing potential damage of flood events is an important component in flood risk management. Determining direct flood damage is commonly done using depth-damage curves, which denote the flood damage that would occur at specific water depths per asset or land-use class. Many countries around the world have developed flood damage models using such curves which are based on analysis of past flood events and/or on expert judgement. However, such damage curves are not available for all regions, which hampers damage assessments in those regions. Moreover, due to different methodologies employed for various damage models in different countries, damage assessments cannot be directly compared with each other, obstructing also supra-national flood damage assessments. To address these problems, a globally consistent dataset of depth-damage curves has been developed. This dataset contains damage curves depicting percent of damage as a function of water depth as well as maximum damage values for a variety of assets and land use classes (i.e. residential, commercial, agriculture). Based on an extensive literature survey concave damage curves have been developed for each continent, while differentiation in flood damage between countries is established by determining maximum damage values at the country scale. These maximum damage values are based on construction cost surveys from multinational construction companies, which provide a coherent set of detailed building cost data across dozens of countries. A consistent set of maximum flood damage values for all countries was computed using statistical regressions with socio-economic World Development Indicators from the World Bank. Further, based on insights from the literature survey, guidance is also given on how the damage curves and maximum damage values can be adjusted for specific local circumstances, such as urban vs. rural locations, use of specific building material, etc. This dataset can be used for consistent supra

  9. CHARACTERIZATION OF DAMAGED MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, P C; Dehaven, M; McClelland, M; Chidester, S; Maienschein, J L

    2006-06-23

    Thermal damage experiments were conducted on LX-04, LX-10, and LX-17 at high temperatures. Both pristine and damaged samples were characterized for their material properties. A pycnometer was used to determine sample true density and porosity. Gas permeability was measured in a newly procured system (diffusion permeameter). Burn rate was measured in the LLNL strand burner. Weight losses upon thermal exposure were insignificant. Damaged pressed parts expanded, resulting in a reduction of bulk density by up to 10%. Both gas permeabilities and burn rates of the damaged samples increased by several orders of magnitude due to higher porosity and lower density. Moduli of the damaged materials decreased significantly, an indication that the materials became weaker mechanically. Damaged materials were more sensitive to shock initiation at high temperatures. No significant sensitization was observed when the damaged samples were tested at room temperature.

  10. COMBINED DAMAGE FRACTURE CRITERIA FOR PIEZOELECTRIC CERAMICS

    Institute of Scientific and Technical Information of China (English)

    Yang Xinhua; Chen Chuanyao; Hu Yuantai; Wang Cheng

    2005-01-01

    Mechanical and electrical damages are introduced to study the fracture mechanics of piezoelectric ceramics in this paper. Two kinds of piezoelectric fracture criteria are established using the method of least squares combined with a damage analysis of the well-known piezoelectric fracture experiments of Park and Sun's. One is based on a linear combination of the mechanical and electrical damages and the other on their nonlinear combination. When the combined damage D is up to its critical value Dc, piezoelectric fracture occurs. It is found from the qualitative comparison of the numerical results with the experimental data that the nonlinearly combined damage fracture criterion can give a better prediction of piezoelectric fracture. And it is concluded from the nonlinearly combined damage fracture criterion that a negative electric field impedes fracture whereas the effect of a positive electric field on fracture depends on its magnitude.

  11. Chromatin structure and DNA damage repair

    Directory of Open Access Journals (Sweden)

    Dinant Christoffel

    2008-11-01

    Full Text Available Abstract The integrity of the genome is continuously challenged by both endogenous and exogenous DNA damaging agents. These damaging agents can induce a wide variety of lesions in the DNA, such as double strand breaks, single strand breaks, oxidative lesions and pyrimidine dimers. The cell has evolved intricate DNA damage response mechanisms to counteract the genotoxic effects of these lesions. The two main features of the DNA damage response mechanisms are cell-cycle checkpoint activation and, at the heart of the response, DNA repair. For both damage signalling and repair, chromatin remodelling is most likely a prerequisite. Here, we discuss current knowledge on chromatin remodelling with respect to the cellular response to DNA damage, with emphasis on the response to lesions resolved by nucleotide excision repair. We will discuss the role of histone modifications as well as their displacement or exchange in nucleotide excision repair and make a comparison with their requirement in transcription and double strand break repair.

  12. 隧道掘进机技术的发展和研究现状%Application,Research and Future of Tunnel Boring Machine Technology

    Institute of Scientific and Technical Information of China (English)

    彭琦

    2013-01-01

    In this article,the classification of tunnel boring machines (TBM),the state-of-the-art of studies on tunnel boring machine technology,and the trend of study and development of tunnel boring machine technology are studied and discussed.Conclusions drawn are as follows:1) According to the strength of the rocks and soils bored,tunnel boring machines can be divided into rock tunnel boring machines and shield machines.2) The hot topics of studies on rock tunnel boring machines include the rock-breaking mechanism of disc cutters and the establishing of TBM performance prediction models.On the other hand,the hot topics of studies on shield machines include the stability of working face,the control of boring process and the study on ground surface settlement.3) Studies on tunnel boring machine technology will focus on the improving of the boring mechanism,the boring mechanism and the boring process control under complex geological conditions,and the development of composite boring technology.%通过对隧道掘进机的分类、隧道掘进机技术的研究现状以及隧道掘进机技术研究和发展趋势的调研和探讨,提出:1)根据掘进岩土体强度的不同,隧道掘进机大致可以分为岩石隧道掘进机和盾构;2)目前岩石隧道掘进机的研究热点问题主要包括滚刀破岩机制和施工预测模型的建立2个方面,而盾构主要研究内容集中在掌子面稳定、施工过程控制和地表沉降研究3个方面,虽然这些研究都取得了较大进展,并且部分已经有效地应用到实际工程建设中,但解决得不够透彻,还有待于进一步研究;3)隧道掘进机技术的研究发展趋势将集中在掘进力学机制的完善、复杂地质条件下掘进机制与施工过程控制研究和复合掘进机技术的发展等方面,这些会给隧道掘进机技术的研究和发展带来挑战和契机.

  13. 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。

  14. 基于ArcGIS Server的海岛管理平台设计与实现%Drawing of bore histogram based on MapInfo

    Institute of Scientific and Technical Information of China (English)

    崔伦辉; 金继业; 刘金

    2011-01-01

    This paper introduced an automatic mapping method based on MapInfo. Also, it discussed how to design bore database and lithological pattern library, and main idea of design, flow methods, key arithmetic of the bore histogram automatically mapping software. The software was developed by OLE technology based on utilizing Maplnfo, Visual Basic and SQL Server 2000. This software realized the management of bore data and automatic mapping with measured bore data. The application of this software could enhance the drawing efficiency and standardization level of bore histogram.%本文基于ArcGIS Server,结合时空数据模型和WebGIS理论,采用Flex技术,面向海岛管理,设计开发了集空间数据、属性信息和时态特性于一体的海岛管理支撑平台,对平台的体系结构、关键技术、数据组织和系统功能作了详细介绍,以期有效管理分布广泛的海岛,充分控制海洋、开发海洋资源.

  15. 钻孔灌注桩砼面标高如何测量及控制%How to Measure and Control the Elevation of Bored Concrete Surface

    Institute of Scientific and Technical Information of China (English)

    任建国

    2011-01-01

    The perfusion underwater concrete is an important process of bored piles construction, and the measurement and control of concrete surface standard is directly related to the quality of bored piles.Therefore, we should improve the study of elevation of bored concrete sudace.Based on the analysis and research on the problems of bored piles technology, this paper puts forward effective measures to measure and control the concrete, to help the application of bored piles technology.%灌注水下砼是钻孔桩施工的重要工序,砼面标准的测量和控制直接关系着钻孔灌注桩的质量.因此,应加大对钻孔灌注桩砼面标高的研究.本文通过对钻孔灌注桩技术存在问题的分析和研究出发,提出了做好砼测量和控制的有效措施,期待对钻孔灌注桩技术的应用有所帮助.

  16. 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。

  17. 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.

  18. 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

  19. 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

    Aquifer-system deformation associated with ground-water-level changes is being investigated cooperatively by the U.S. Geological Survey (USGS) and the East Bay Municipal Utility District (EBMUD) at the Bayside Groundwater Project (BGP) near the modern San Francisco Bay shore in San Lorenzo, California. As a part of this project, EBMUD has proposed an aquifer storage and recovery (ASR) program to store and recover as much as 3.78x104 m3/d of water. Water will be stored in a 30-m sequence of coarse-grained sediment (the 'Deep Aquifer') underlying the east bay alluvium and the adjacent ground-water basin. Storing and recovering water could cause subsidence and uplift at the ASR site and adjacent areas because the land surface will deform as aquifers and confining units elastically expand and contract with ASR cycles. The Deep Aquifer is overlain by more than 150 m of clayey fine-grained sediments and underlain by comparable units. These sediments are similar to the clayey sediments found in the nearby Santa Clara Valley, where inelastic compaction resulted in about 4.3 m of subsidence near San Jose from 1910 to 1995 due to overdraft of the aquifer. The Deep Aquifer is an important regional resource, and EBMUD is required to demonstrate that ASR activities will not affect nearby ground-water management, salinity levels, or cause permanent land subsidence. Subsidence in the east bay area could induce coastal flooding and create difficulty conveying winter storm runoff from urbanized areas. The objective of the cooperative investigation is to monitor and analyze aquifer-system compaction and expansion, as well as consequent land subsidence and uplift resulting from natural causes and any anthropogenic causes related to ground-water development and ASR activities at the BGP. Therefore, soil properties related to compressibility (and the potential for deformation associated with ground-water-level changes) are of the most concern. To achieve this objective, 3 boreholes

  20. Sandy Damage Estimates by Block Group

    Data.gov (United States)

    Department of Housing and Urban Development — A FEMA housing inspection for renters is used to assess personal property loss and for owners to assess damage to their home as well as personal property. This...

  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. 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。

  3. 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.

  4. 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.

  5. 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.

  6. A cradle-shaped gradient coil to expand the clear-bore width of an animal MRI scanner.

    Science.gov (United States)

    Gilbert, K M; Gati, J S; Klassen, L M; Menon, R S

    2010-01-21

    The never ending quest for higher magnetic field strengths in MRI and MRS has led to small and medium bore scanners at 9.4 T and above for both human and animal use; however, these bore diameters restrict the size of object that can be accommodated when using a conventional gradient coil. By replacing a cylindrical gradient-coil insert with a single-sided gradient coil, the scanner's functionality can be extended to include localized imaging of wider samples. As a prototype, a three-axis, cradle-shaped gradient coil was designed, fabricated and implemented in a 9.4 T animal MRI scanner. Since gradient fields are required only to be monotonic over the desired field of view, the cradle gradient coil was designed to produce high gradient efficiencies (up to 2.25 mT m(-1) A(-1) over a 5 cm imaging region) at the expense of gradient linearity. A dedicated three-dimensional algorithm was developed to correct the resultant image distortion. Preliminary images of a grid phantom and a mouse demonstrated the fidelity of the algorithm in correcting image distortion of greater than 200%. Eddy currents were measured along each gradient axis. A large 65.2 (Hz mT(-1) m) B(0) eddy current was produced by the y-axis, suggesting potential limitations of single-sided gradient coils.

  7. Oxygen Reperfusion Damage in an Insect

    OpenAIRE

    2007-01-01

    The deleterious effects of anoxia followed by reperfusion with oxygen in higher animals including mammals are well known. A convenient and genetically well characterized small-animal model that exhibits reproducible, quantifiable oxygen reperfusion damage is currently lacking. Here we describe the dynamics of whole-organism metabolic recovery from anoxia in an insect, Drosophila melanogaster, and report that damage caused by oxygen reperfusion can be quantified in a novel but straightforward ...

  8. MR imaging of claustrophobic patients in an open 1.0T scanner: motion artifacts and patient acceptability compared with closed bore magnets.

    Science.gov (United States)

    Bangard, Christopher; Paszek, Jennifer; Berg, Frank; Eyl, Gesa; Kessler, Josef; Lackner, Klaus; Gossmann, Axel

    2007-10-01

    To evaluate motion artifacts and patient acceptability of MR imaging of claustrophobic patients in an open 1.0T scanner. Thirty six claustrophobic patients were enrolled prospectively, 34 of which had previous MR examinations in closed bore magnets. Anxiety and pain during MR examination in an open 1.0T scanner were evaluated by visual analogue scales and various tests. Influence of motion artifacts on image quality was evaluated by two radiologists independently using a five-point scale. Additionally, 36 non-claustrophobic patients delivered a reference value of a non-claustrophobic population for the visual analogue anxiety scale. Termination rate of MR imaging of highly claustrophobic patients decreased from 58.3% (n=21) in closed bore magnets to 8.3% (n=3) in the open scanner (pclaustrophobic patients compared with closed bore magnets. Motion artifacts did not influence image quality.

  9. 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.

  10. 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。

  11. Animal damage to birch

    Science.gov (United States)

    James S. Jordan; Francis M. Rushmore

    1969-01-01

    A relatively few animal species are responsible for most of the reported damage to the birches. White-tailed deer, yellow-bellied sapsuckers, porcupines, moose, and hares are the major animals involved. We will review reports of damage, discuss the underlying causes, and describe possible methods of control. For example, heavy deer browsing that eliminates birch...

  12. Animal damage management handbook.

    Science.gov (United States)

    Hugh C. Black

    1994-01-01

    This handbook treats animal damage management (ADM) in the West in relation to forest, range, and recreation resources; predator management is not addressed. It provides a comprehensive reference of safe, effective, and practical methods for managing animal damage on National Forest System lands. Supporting information is included in references after each chapter and...

  13. DNA damage and autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rocha, Humberto; Garcia-Garcia, Aracely [Redox Biology Center and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583 (United States); Panayiotidis, Mihalis I. [School of Community Health Sciences, University of Nevada, Reno, NV 89557 (United States); Franco, Rodrigo, E-mail: rfrancocruz2@unl.edu [Redox Biology Center and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583 (United States)

    2011-06-03

    Both exogenous and endogenous agents are a threat to DNA integrity. Exogenous environmental agents such as ultraviolet (UV) and ionizing radiation, genotoxic chemicals and endogenous byproducts of metabolism including reactive oxygen species can cause alterations in DNA structure (DNA damage). Unrepaired DNA damage has been linked to a variety of human disorders including cancer and neurodegenerative disease. Thus, efficient mechanisms to detect DNA lesions, signal their presence and promote their repair have been evolved in cells. If DNA is effectively repaired, DNA damage response is inactivated and normal cell functioning resumes. In contrast, when DNA lesions cannot be removed, chronic DNA damage triggers specific cell responses such as cell death and senescence. Recently, DNA damage has been shown to induce autophagy, a cellular catabolic process that maintains a balance between synthesis, degradation, and recycling of cellular components. But the exact mechanisms by which DNA damage triggers autophagy are unclear. More importantly, the role of autophagy in the DNA damage response and cellular fate is unknown. In this review we analyze evidence that supports a role for autophagy as an integral part of the DNA damage response.

  14. Damage Theory Validation

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1998-01-01

    This report contains a series of validation examples for the theoretical model implemented in the computer program DAMAGE. note that the validation examples are for assembled structures.......This report contains a series of validation examples for the theoretical model implemented in the computer program DAMAGE. note that the validation examples are for assembled structures....

  15. 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

  16. 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.

  17. 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

  18. Drivers of flood damage on event level

    DEFF Research Database (Denmark)

    Kreibich, H.; Aerts, J. C. J. H.; Apel, H.

    2016-01-01

    Flood risk is dynamic and influenced by many processes related to hazard, exposure and vulnerability. Flood damage increased significantly over the past decades, however, resulting overall economic loss per event is an aggregated indicator and it is difficult to attribute causes to this increasing...... trend. Much has been learned about damaging processes during floods at the micro-scale, e.g. building level. However, little is known about the main factors determining the amount of flood damage on event level. Thus, we analyse and compare paired flood events, i.e. consecutive, similar damaging floods...... that occurred in the same area. In analogy to ’Paired catchment studies’ - a well-established method in hydrology to understand how changes in land use affect streamflow – we will investigate how and why resulting flood damage in a region differed between the first and second consecutive flood events. One...

  19. 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.

  20. Wickerhamomyces mori sp. nov., an anamorphic yeast species found in the guts of wood-boring insect larvae.

    Science.gov (United States)

    Hui, Feng-Li; Chen, Liang; Chu, Xue-Ying; Niu, Qiu-Hong; Ke, Tao

    2013-03-01

    A novel anamorphic yeast species is described to accommodate three isolates recovered from the guts of three different wood-boring insect larvae collected in Henan, central China. On the basis of sequence analyses of the D1/D2 domains of the large-subunit rRNA gene and the internal transcribed spacer regions, the three strains are assigned to a novel species of the genus Wickerhamomyces, although the formation of ascospores was not observed. These strains also exhibited a number of distinct morphological and physiological characteristics that clearly differentiated them from Wickerhamomyces mucosus, Candida odintsovae and Wickerhamomyces rabaulensis, the most closely related species. In view of the phenotypic differences and unique rRNA gene sequences, we consider that these three isolates represent a novel species of the genus Wickerhamomyces, Wickerhamomyces mori sp. nov. The type strain is NYNU 1216(T) ( = CICC 1983(T)  = CBS 12678(T)).

  1. 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.

  2. ASSEMBLY AND TEST OF A 120 MM BORE 15 T NB3SN QUADRUPOLE FOR THE LHC UPGRADE

    Energy Technology Data Exchange (ETDEWEB)

    Felice, H.; Caspi, S.; Cheng, D.; Dietderich, D.; Ferracin, P.; Hafalia, R.; Joseph, J.; Lizarazo, J.; Sabbi, G. L.; Wang, X.; Anerella, M.; Ghosh, A. K.; Schmalzle, J.; Wanderer, P.; Ambrosio, G.; Bossert, R.; Zlobin, A. V.

    2010-05-23

    In support of the Large Hadron Collider (LHC) luminosity upgrade, the US LHC Accelerator Research Program (LARP) has been developing a 1-meter long, 120 mm bore Nb{sub 3}Sn IR quadrupole magnet (HQ). With a design short sample gradient of 219 T/m at 1.9 K and a peak field approaching 15 T, one of the main challenges of this magnet is to provide appropriate mechanical support to the coils. Compared to the previous LARP Technology Quadrupole and Long Quadrupole magnets, the purpose of HQ is also to demonstrate accelerator quality features such as alignment and cooling. So far, 8 HQ coils have been fabricated and 4 of them have been assembled and tested in HQ01a. This paper presents the mechanical assembly and test results of HQ01a.

  3. 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.

  4. Review article "Assessment of economic flood damage"

    Directory of Open Access Journals (Sweden)

    B. Merz

    2010-08-01

    Full Text Available Damage assessments of natural hazards supply crucial information to decision support and policy development in the fields of natural hazard management and adaptation planning to climate change. Specifically, the estimation of economic flood damage is gaining greater importance as flood risk management is becoming the dominant approach of flood control policies throughout Europe. This paper reviews the state-of-the-art and identifies research directions of economic flood damage assessment. Despite the fact that considerable research effort has been spent and progress has been made on damage data collection, data analysis and model development in recent years, there still seems to be a mismatch between the relevance of damage assessments and the quality of the available models and datasets. Often, simple approaches are used, mainly due to limitations in available data and knowledge on damage mechanisms. The results of damage assessments depend on many assumptions, e.g. the selection of spatial and temporal boundaries, and there are many pitfalls in economic evaluation, e.g. the choice between replacement costs or depreciated values. Much larger efforts are required for empirical and synthetic data collection and for providing consistent, reliable data to scientists and practitioners. A major shortcoming of damage modelling is that model validation is scarcely performed. Uncertainty analyses and thorough scrutiny of model inputs and assumptions should be mandatory for each damage model development and application, respectively. In our view, flood risk assessments are often not well balanced. Much more attention is given to the hazard assessment part, whereas damage assessment is treated as some kind of appendix within the risk analysis. Advances in flood damage assessment could trigger subsequent methodological improvements in other natural hazard areas with comparable time-space properties.

  5. Review article "Assessment of economic flood damage"

    Science.gov (United States)

    Merz, B.; Kreibich, H.; Schwarze, R.; Thieken, A.

    2010-08-01

    Damage assessments of natural hazards supply crucial information to decision support and policy development in the fields of natural hazard management and adaptation planning to climate change. Specifically, the estimation of economic flood damage is gaining greater importance as flood risk management is becoming the dominant approach of flood control policies throughout Europe. This paper reviews the state-of-the-art and identifies research directions of economic flood damage assessment. Despite the fact that considerable research effort has been spent and progress has been made on damage data collection, data analysis and model development in recent years, there still seems to be a mismatch between the relevance of damage assessments and the quality of the available models and datasets. Often, simple approaches are used, mainly due to limitations in available data and knowledge on damage mechanisms. The results of damage assessments depend on many assumptions, e.g. the selection of spatial and temporal boundaries, and there are many pitfalls in economic evaluation, e.g. the choice between replacement costs or depreciated values. Much larger efforts are required for empirical and synthetic data collection and for providing consistent, reliable data to scientists and practitioners. A major shortcoming of damage modelling is that model validation is scarcely performed. Uncertainty analyses and thorough scrutiny of model inputs and assumptions should be mandatory for each damage model development and application, respectively. In our view, flood risk assessments are often not well balanced. Much more attention is given to the hazard assessment part, whereas damage assessment is treated as some kind of appendix within the risk analysis. Advances in flood damage assessment could trigger subsequent methodological improvements in other natural hazard areas with comparable time-space properties.

  6. Cumulative fatigue damage models

    Science.gov (United States)

    Mcgaw, Michael A.

    1988-01-01

    The problem of calculating expected component life under fatigue loading conditions is complicated by the fact that component loading histories contain, in many cases, cyclic loads of widely varying amplitudes. In such a case a cumulative damage model is required, in addition to a fatigue damage criterion, or life relationship, in order to compute the expected fatigue life. The traditional cumulative damage model used in design is the linear damage rule. This model, while being simple to use, can yield grossly unconservative results under certain loading conditions. Research at the NASA Lewis Research Center has led to the development of a nonlinear cumulative damage model, named the double damage curve approach (DDCA), that has greatly improved predictive capability. This model, which considers the life (or loading) level dependence of damage evolution, was applied successfully to two polycrystalline materials, 316 stainless steel and Haynes 188. The cumulative fatigue behavior of the PWA 1480 single-crystal material is currently being measured to determine the applicability of the DDCA for this material.

  7. A damage model for fracking

    CERN Document Server

    Norris, J Quinn; Rundle, John B

    2015-01-01

    Injections of large volumes of water into tight shale reservoirs allows the extraction of oil and gas not previously accessible. This large volume "super" fracking induces damage that allows the oil and/or gas to flow to an extraction well. The purpose of this paper is to provide a model for understanding super fracking. We assume that water is injected from a small spherical cavity into a homogeneous elastic medium. The high pressure of the injected water generates hoop stresses that reactivate natural fractures in the tight shales. These fractures migrate outward as water is added creating a spherical shell of damaged rock. The porosity associated with these fractures is equal to the water volume injected. We obtain an analytic expression for this volume. We apply our model to a typical tight shale reservoir and show that the predicted water volumes are in good agreement with the volumes used in super fracking.

  8. 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.

  9. 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。

  10. Diabetes and nerve damage

    Science.gov (United States)

    Diabetic neuropathy; Diabetes - neuropathy; Diabetes - peripheral neuropathy ... In people with diabetes, the body's nerves can be damaged by decreased blood flow and a high blood sugar level. This condition is ...

  11. LSD and Genetic Damage

    Science.gov (United States)

    Dishotsky, Norman I.; And Others

    1971-01-01

    Reviews studies of the effects of lysergic acid diethylamide (LSD) on man and other organisms. Concludes that pure LSD injected in moderate doses does not cause chromosome or detectable genetic damage and is not a teratogen or carcinogen. (JM)

  12. LSD and Genetic Damage

    Science.gov (United States)

    Dishotsky, Norman I.; And Others

    1971-01-01

    Reviews studies of the effects of lysergic acid diethylamide (LSD) on man and other organisms. Concludes that pure LSD injected in moderate doses does not cause chromosome or detectable genetic damage and is not a teratogen or carcinogen. (JM)

  13. First horizontal well opens new gas opportunities in the Sierra Chata Field Neuquen Basin-Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, C.A.; Nilson, G.J.; Acree, J.F.; Del Pino, M.A. [Devon Energy Corp., Calgary, AB (Canada); Anaya, L. [BJ Services Co. USA, Houston, TX (United States)

    2002-07-01

    This paper described the drilling activity surrounding the first horizontal re-entry gas well in the Sierra Chata field in the Neuquen basin in Argentina. In particular, a model forecast was compared with the final results. The re-entry well was originally designed to add gas reserves and to incorporate horizontal well technology to help access the thin sands with low permeability. A numeric simulation of the 1000 m horizontal well was used to predict an initial gas flow rate of 17.7 MMscfd with an estimated final recovery of 7.3 Bscf. This forecast was confirmed following the first year of production. Operational problems, however, were encountered and new solutions were needed to bring the well back on line. The use of an existing well bore saved $1 MM and improved the economics of the project. When re-entering the existing well bore, no new flow line was needed. Given the success of this first re-entry well, it was suggested that this technology can now be used for the Machiline formation which has low productivity for several reasons, including thin sands, low permeability and difficult access via vertical wells. The use of mud logs and resistivity/gamma ray logs while drilling was very important for geological control purposes. It was noted that a measurement while drilling (MWD) tool closer to the bit would have further improved the ability to stay within very thin target zones. 11 refs., 19 figs.

  14. Bypassing damaged nervous tissue

    CERN Document Server

    Shneider, M N

    2016-01-01

    We show the principal ability of bypassing damaged demyelinated portions of nervous tissue, thereby restoring its normal function for the passage of action potentials. We carry out a theoretical analysis on the basis of the synchronization mechanism of action potential propagation along a bundle of neurons, proposed recently in [1]. And we discuss the feasibility of implement a bypass to restore damaged nervous tissue and creating an artificial neuron network.

  15. 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

  16. Typical Cell Signaling Response to Ionizing Radiation:DNA Damage and Extranuclear Damage

    Institute of Scientific and Technical Information of China (English)

    Hui Yu

    2012-01-01

    To treat many types of cancer,ionizing radiation (IR) is primarily used as external-beam radiotherapy,brachytherapy,and targeted radionuclide therapy.Exposure of tumor cells to IR can induce DNA damage as well as generation of reactiveoxygen species (ROS) and reactive nitrogen species (RNS) which can cause non-DNA lesions or extracellular damage like lipid perioxidation.The initial radiation-induced cell responses to DNA damage and ROS like the proteolytic processing,as well as synthesis and releasing ligands (such as growth factors,cytokines,and hormone) can cause the delayed secondary responses in irradiated and unirradiated bystander cells through paracrine and autocrine pathways.

  17. Single well surfactant test to evaluate surfactant floods using multi tracer method

    Science.gov (United States)

    Sheely, Clyde Q.

    1979-01-01

    Data useful for evaluating the effectiveness of or designing an enhanced recovery process said process involving mobilizing and moving hydrocarbons through a hydrocarbon bearing subterranean formation from an injection well to a production well by injecting a mobilizing fluid into the injection well, comprising (a) determining hydrocarbon saturation in a volume in the formation near a well bore penetrating formation, (b) injecting sufficient mobilizing fluid to mobilize and move hydrocarbons from a volume in the formation near the well bore, and (c) determining the hydrocarbon saturation in a volume including at least a part of the volume of (b) by an improved single well surfactant method comprising injecting 2 or more slugs of water containing the primary tracer separated by water slugs containing no primary tracer. Alternatively, the plurality of ester tracers can be injected in a single slug said tracers penetrating varying distances into the formation wherein the esters have different partition coefficients and essentially equal reaction times. The single well tracer method employed is disclosed in U.S. Pat. No. 3,623,842. This method designated the single well surfactant test (SWST) is useful for evaluating the effect of surfactant floods, polymer floods, carbon dioxide floods, micellar floods, caustic floods and the like in subterranean formations in much less time and at much reduced cost compared to conventional multiwell pilot tests.

  18. Laser Damage Inspection Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, J T; Brase, J M; Bliss, E S; Carrano, C J; Kegelmeyer, L M; Miller, M G; Orth, C D; Sacks, R A

    2001-02-26

    Large, high-power laser systems are often designed as reimaging multipass cavities to maximize the extraction of energy from the amplifiers. These multipass cavities often have vacuum spatial filters that suppress the growth of beam instability via B-integral effects. These spatial filters also relay images of laser damage, often nearly superimposing these images in common planes. Also, the fluence damage threshold limits the minimum size of the optics. When used as vacuum barriers in the spatial filters, these large optics present a safety hazard from the risk of implosion if the laser damage were sufficiently large. The objective of the project was to develop algorithms and methods for optical detection and characterization of laser-induced damage of optics. The system should detect small defects (about 5% of the critical size), track their growth over multiple laser shots, and characterize the defects accurately so that the optic can be replaced (at 25% of the critical size) and, hence, minimize the risk of implosion. The depth of field must be short enough to isolate the damaged vacuum barrier from other damaged optics in the beamline, and the system should also be capable of inspecting other optics in the beamline, since damage on one optic can subsequently damage subsequent optics. Laser induced damage starts as a small (<<1mm) crater and grows as material is removed on subsequent laser shots. The highly fractured rough surface of the crater scatters light from the illuminating inspection beam. This scattered light is imaged by the inspection system. Other types of defects may occur as well including inclusions in the bulk glass, tooling marks, and surface contamination. This report will discuss the detection and characterization of crater-like surface defects although the general techniques may prove useful for other types of defects. The work described here covers the development of an image processing approach and specific algorithms for defect detection

  19. Dynamic Damage Model of Brittle Rock and Its Application

    Institute of Scientific and Technical Information of China (English)

    高文学; 刘运通; 杨军; 黄风雷

    2003-01-01

    On the basis of shock-induced experiments and the ultrasonic tests of the damaged rocks, the damage evolution relation between the attenuation coefficient of sound wave and the damage dissipated energy is described. Based on the TCK and RDA models, a damage model which connects the shock compression and tensile damage is established. And then the damage model is implemented in LS-DYNA3D dynamic nonlinear program. Numerical simulation of deep-hole blasting of groove is studied by use of the damage model proposed. The rock damage evolution process and the distributing rules of stress field under the explosion load are described well fairly, which provides the theory basis for the engineering blasting design.

  20. A continuum damage model for piezoelectric materials

    Institute of Scientific and Technical Information of China (English)

    Yiming Fu; Xianqiao Wang

    2008-01-01

    In this paper, a constitutive model is proposed for piezoelectric material solids containing distributed cracks.The model is formulated in a framework of continuum damage mechanics using second rank tensors as internal variables. The Helmhotlz free energy of piezoelectric mate-rials with damage is then expressed as a polynomial including the transformed strains, the electric field vector and the ten-sorial damage variables by using the integrity bases restricted by the initial orthotropic symmetry of the material. By using the Talreja's tensor valued internal state damage variables as well as the Helmhotlz free energy of the piezoelectric mate-rial, the constitutive relations of piezoelectric materials with damage are derived. The model is applied to a special case of piezoelectric plate with transverse matrix cracks. With theKirchhoff hypothesis of plate, the free vibration equationsof the piezoelectric rectangular plate considering damage isestablished. By using Galerkin method, the equations are sol-ved. Numerical results show the effect of the damage on the free vibration of the piezoelectric plate under the close-circuit condition, and the present results are compared with those of the three-dimensional theory.

  1. 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

  2. Well-being

    OpenAIRE

    Blatný, M. (Marek); Šolcová, I. (Iva)

    2015-01-01

    The chapter first discusses two essential theoretical concepts of well-being: subjective well-being and psychological well-being. Then the main findings on the links between well-being and socio-demographic variables are summarized. The main focus of the chapter is on the analysis of the links between personality and well-being. In agreement with the present views on personality domains, the relationships between well-being and personality traits, characteristic adaptations and personal narra...

  3. 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

  4. Indirect identification of damage functions from damage records

    CERN Document Server

    Steinhäuser, J Micha; Kropp, Jürgen P

    2015-01-01

    In order to assess future damage caused by natural disasters, it is desirable to estimate the damage caused by single events. So called damage functions provide -- for a natural disaster of certain magnitude -- a specific damage value. However, in general, the functional form of such damage functions is unknown. We study the distributions of recorded flood damages on extended scales and deduce which damage functions lead to such distributions when the floods obey Generalized Extreme Value statistics and follow Generalized Pareto distributions. Based on the finding of broad damage distributions we investigate two possible functional forms to characterize the data. In the case of Gumbel distributed extreme events, (i) a power-law distribution density with an exponent close to 2 (Zipf's law) implies an exponential damage function; (ii) stretched exponential distribution densities imply power-law damage functions. In the case of Weibull (Frechet) distributed extreme events we find correspondingly steeper (less st...

  5. Damage Tolerance Assessment Branch

    Science.gov (United States)

    Walker, James L.

    2013-01-01

    The Damage Tolerance Assessment Branch evaluates the ability of a structure to perform reliably throughout its service life in the presence of a defect, crack, or other form of damage. Such assessment is fundamental to the use of structural materials and requires an integral blend of materials engineering, fracture testing and analysis, and nondestructive evaluation. The vision of the Branch is to increase the safety of manned space flight by improving the fracture control and the associated nondestructive evaluation processes through development and application of standards, guidelines, advanced test and analytical methods. The Branch also strives to assist and solve non-aerospace related NDE and damage tolerance problems, providing consultation, prototyping and inspection services.

  6. Crumpling Damaged Graphene

    CERN Document Server

    Giordanelli, I; Andrade,, J S; Gomes, M A F; Herrmann, H J

    2016-01-01

    Through molecular mechanics we find that non-covalent interactions modify the fractality of crumpled damaged graphene. Pristine graphene membranes are damaged by adding random vacancies and carbon-hydrogen bonds. Crumpled membranes exhibit a fractal dimension of $ 2.71 \\pm 0.02$ when all interactions between carbon atoms are considered, and $2.30 \\pm 0.05$ when non-covalent interactions are suppressed. The transition between these two values, obtained by switching on/off the non-covalent interactions of equilibrium configurations, is shown to be reversible and independent on thermalisation. In order to explain this transition, we propose a theoretical model that is compatible with our numerical findings. Finally, we also compare damaged graphene membranes with other crumpled structures, as for instance, polymerised membranes and paper sheets, that share similar scaling properties.

  7. Testing geopressured geothermal reservoirs in existing wells: Detailed completions prognosis for geopressured-geothermal well of opportunity, prospect #1

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, Clovis A.

    1980-04-03

    This prospective well of opportunity was originally drilled and completed as a gas producer by Wrightsman Investment Company in early 1973. The original and present producing interval was from 15,216 to 15,238 feet. IMC Exploration Company, Inc. acquired the property from Wrightsman and is the present owner operator. The well is presently shut in s a non-economic producer and IMC proposed to perform plug and abandonment operations in April, 1980. This well has a good geopressured-geothermal water sand behind the 5-1/2 inch casing that has 94 feet of net sand thickness. Pursuant to DOE/NVO authorization of March 11,1980, Eaton negotiated an option agreement with IMC whereby IMC would delay their abandonment operations for a period of 90 days to permit DOE to evaluate the well for geopressure-geothermal testing. The IMC-Eaton option agreements provide that IMG will delay plugging the well until June 15, 1980. If Eaton exercises its option to acquire the well, IMC will sell the well bore, and an adjacent salt water disposal well, to Eaton for the sole consideration of Eaton assuming the obligation to plug and abandon the wells in accordance with lease and regulatory requirements. If Eaton does not exercise its option, then Eaton will pay IMC $95,000 cash and IMC will proceed with plugging and abandonment at the termination of the option period.

  8. Comparison of the efficacy of small and large-bore thoracostomy tubes for pleural space evacuation in canine cadavers.

    Science.gov (United States)

    Fetzer, Tara J; Walker, Julie M; Bach, Jonathan F

    2017-05-01

    To determine if there is a difference in the amounts of air (A), low-viscosity fluid (LV), or high-viscosity fluid (HV) that can be aspirated from the pleural cavity of canine cadavers using small-bore (SB) or large-bore (LB) thoracostomy tubes. Prospective experimental ex vivo study. University teaching hospital. Thirty-six canine cadavers. Each cadaver was randomly assigned to 1 of 6 groups (SB-A, LB-A, SB-LV, LB-LV, SB-HV, LB-HV). In each cadaver bilateral thoracostomy tubes (either SB or LB) were placed and 20 mL/kg of air, LV fluid, or HV fluid was instilled via 1 thoracostomy tube. Both tubes were aspirated and the volume aspirated was recorded and analyzed as a percentage of instilled air or fluid volume. The procedure was repeated on the contralateral hemithorax. There was no significant difference in air or fluid recovery when SB and LB groups were compared. Median (range) air recovery volumes in the SB-A and LB-A groups were 101.5% (94.4-115.8%) and 102.8% (94.1-107.8%), respectively (P = 0.898). Recovery of LV fluid was 93.5% (79.2-99.0%) for SB-LV and 85.8% (77.1-101.8%) for LB-LV cadavers (P = 0.305) and recovery percentages of HV fluid were 92.6% (86.1-96.2%) and 91.4% (74.2-96.4%) for SB-HV and LB-HV groups, respectively (P > 0.999). There was no significant difference between SB and LB groups when all substances were combined (94.1% [79.2-115.8%] and 93.5% [74.2-107.8%], respectively, P = 0.557). SB and LB thoracostomy tubes demonstrated similar efficacy in removing known amounts of air, LV fluid, and HV fluid from the pleural space of canine cadavers. Further study is necessary to determine if SB and LB thoracostomy tubes demonstrate similar efficacy in clinical veterinary patients. © Veterinary Emergency and Critical Care Society 2017.

  9. 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

  10. Experimental study of oxidative DNA damage

    DEFF Research Database (Denmark)

    Loft, S; Deng, Xiaohong; Tuo, J

    1998-01-01

    compounds have been studied in animal experiments mainly in rats and mice, and generally with measurement of 8-oxodG with HPLC-EC. A large number of well-known carcinogens induce 8-oxodG formation in liver and/or kidneys. Moreover several animal studies have shown a close relationship between induction...... of the use of 2-nitropropane as a model for oxidative DNA damage relate particularly to formation of 8-aminoguanine derivatives that may interfere with HPLC-EC assays and have unknown consequences. Other model compounds for induction of oxidative DNA damage, such as ferric nitriloacetate, iron dextran......, potassium bromate and paraquat, are less potent and/or more organ specific. Inflammation and activation of an inflammatory response by phorbol esters or E. coli lipopolysaccharide (LPS) induce oxidative DNA damage in many target cells and enhance benzene-induced DNA damage in mouse bone marrow. Experimental...

  11. Damage modelling in plasma facing components

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E. [Universite Bordeaux 1, UMR 5801 (CNRS-SPS-CEA-UB1), Laboratoire des Composites Thermostructuraux, F-33600 Pessac (France)], E-mail: martin@lcts.u-bordeaux1.fr; Camus, G. [Universite Bordeaux 1, UMR 5801 (CNRS-SPS-CEA-UB1), Laboratoire des Composites Thermostructuraux, F-33600 Pessac (France); Schlosser, J.; Chevet, G. [Association Euratom-CEA, DSM/DRFC, CEA Cadarache, St. Paul Lez Durance (France)

    2009-04-30

    The plasma facing components of controlled fusion devices are submitted to high heat fluxes in operating conditions (from 10 to 20 MW/m{sup 2}). These components are made of a carbon/carbon composite tile bonded to a copper alloy heat sink. Due to the thermal expansion mismatch between the composite and the copper alloy, significant stresses may develop during fabrication and under heat load inducing damage in the composite material as well as at the copper/composite interface. The present study describes a modelling approach aimed at predicting damage development in plasma facing components. For this purpose, damage laws related to the non-linear behaviour of both the composite material and the copper/composite joint have been identified. These constitutive laws were then introduced in a numerical model representative of a plasma facing component. Results show the development of damage within the assembly submitted to a heat load.

  12. The DNA damage response during mitosis.

    Science.gov (United States)

    Heijink, Anne Margriet; Krajewska, Małgorzata; van Vugt, Marcel A T M

    2013-10-01

    Cells are equipped with a cell-intrinsic signaling network called the DNA damage response (DDR). This signaling network recognizes DNA lesions and initiates various downstream pathways to coordinate a cell cycle arrest with the repair of the damaged DNA. Alternatively, the DDR can mediate clearance of affected cells that are beyond repair through apoptosis or senescence. The DDR can be activated in response to DNA damage throughout the cell cycle, although the extent of DDR signaling is different in each cell cycle phase. Especially in response to DNA double strand breaks, only a very marginal response was observed during mitosis. Early on it was recognized that cells which are irradiated during mitosis continued division without repairing broken chromosomes. Although these initial observations indicated diminished DNA repair and lack of an acute DNA damage-induced cell cycle arrest, insight into the mechanistic re-wiring of DDR signaling during mitosis was only recently provided. Different mechanisms appear to be at play to inactivate specific signaling axes of the DDR network in mitosis. Importantly, mitotic cells not simply inactivate the entire DDR, but appear to mark their DNA damage for repair after mitotic exit. Since the treatment of cancer frequently involves agents that induce DNA damage as well as agents that block mitotic progression, it is clinically relevant to obtain a better understanding of how cancer cells deal with DNA damage during interphase versus mitosis. In this review, the molecular details concerning DDR signaling during mitosis as well as the consequences of encountering DNA damage during mitosis for cellular fate are discussed.

  13. The DNA damage response during mitosis

    Energy Technology Data Exchange (ETDEWEB)

    Heijink, Anne Margriet; Krajewska, Małgorzata; Vugt, Marcel A.T.M. van, E-mail: m.vugt@umcg.nl

    2013-10-15

    Cells are equipped with a cell-intrinsic signaling network called the DNA damage response (DDR). This signaling network recognizes DNA lesions and initiates various downstream pathways to coordinate a cell cycle arrest with the repair of the damaged DNA. Alternatively, the DDR can mediate clearance of affected cells that are beyond repair through apoptosis or senescence. The DDR can be activated in response to DNA damage throughout the cell cycle, although the extent of DDR signaling is different in each cell cycle phase. Especially in response to DNA double strand breaks, only a very marginal response was observed during mitosis. Early on it was recognized that cells which are irradiated during mitosis continued division without repairing broken chromosomes. Although these initial observations indicated diminished DNA repair and lack of an acute DNA damage-induced cell cycle arrest, insight into the mechanistic re-wiring of DDR signaling during mitosis was only recently provided. Different mechanisms appear to be at play to inactivate specific signaling axes of the DDR network in mitosis. Importantly, mitotic cells not simply inactivate the entire DDR, but appear to mark their DNA damage for repair after mitotic exit. Since the treatment of cancer frequently involves agents that induce DNA damage as well as agents that block mitotic progression, it is clinically relevant to obtain a better understanding of how cancer cells deal with DNA damage during interphase versus mitosis. In this review, the molecular details concerning DDR signaling during mitosis as well as the consequences of encountering DNA damage during mitosis for cellular fate are discussed.

  14. Dynamic reservoir well interaction

    NARCIS (Netherlands)

    Sturm, W.L.; Belfroid, S.P.C.; Wolfswinkel, O. van; Peters, M.C.A.M.; Verhelst, F.J.P.C.M.

    2004-01-01

    In order to develop smart well control systems for unstable oil wells, realistic modeling of the dynamics of the well is essential. Most dynamic well models use a semi-steady state inflow model to describe the inflow of oil and gas from the reservoir. On the other hand, reservoir models use steady s

  15. DAMAGE MORPHOLOGICAL PARAMETERS

    Directory of Open Access Journals (Sweden)

    Jean-Louis Chermant

    2011-05-01

    Full Text Available This paper shows how it is possible to characterize and quantify the damages in materials using classical tools of automatic image analysis. Examples presented concern ceramic matrix composites, i.e. high tech materials. It gives important information to support the deformation and rupture mechanism of materials under mechanical solicitations.

  16. Loss and damage

    Science.gov (United States)

    Huq, Saleemul; Roberts, Erin; Fenton, Adrian

    2013-11-01

    Loss and damage is a relative newcomer to the climate change agenda. It has the potential to reinvigorate existing mitigation and adaptation efforts, but this will ultimately require leadership from developed countries and enhanced understanding of several key issues, such as limits to adaptation.

  17. mapDamage

    DEFF Research Database (Denmark)

    Ginolhac, Aurélien; Rasmussen, Morten; Gilbert, Tom

    2011-01-01

    Ancient DNA extracts consist of a mixture of contaminant DNA molecules, most often originating from environmental microbes, and endogenous fragments exhibiting substantial levels of DNA damage. The latter introduce specific nucleotide misincorporations and DNA fragmentation signatures in sequenci...... of the SAMtools suite and R environment and has been validated on both GNU/Linux and MacOSX operating systems....

  18. 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.

  19. Development of Neural Network Model for Predicting Peak Ground Acceleration Based on Microtremor Measurement and Soil Boring Test Data

    Directory of Open Access Journals (Sweden)

    T. Kerh

    2012-01-01

    Full Text Available It may not be possible to collect adequate records of strong ground motions in a short period of time; hence microtremor survey is frequently conducted to reveal the stratum structure and earthquake characteristics at a specified construction site. This paper is therefore aimed at developing a neural network model, based on available microtremor measurement and on-site soil boring test data, for predicting peak ground acceleration at a site, in a science park of Taiwan. The four key parameters used as inputs for the model are soil values of the standard penetration test, the medium grain size, the safety factor against liquefaction, and the distance between soil depth and measuring station. The results show that a neural network model with four neurons in the hidden layer can achieve better performance than other models presently available. Also, a weight-based neural network model is developed to provide reliable prediction of peak ground acceleration at an unmeasured site based on data at three nearby measuring stations. The method employed in this paper provides a new way to treat this type of seismic-related problem, and it may be applicable to other areas of interest around the world.

  20. 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.

  1. Cryptococcus nanyangensis sp. nov., a new basidiomycetous yeast isolated from the gut of wood-boring larvae.

    Science.gov (United States)

    Hui, Feng-Li; Niu, Qiu-Hong; Ke, Tao; Li, Ying-Xia

    2012-11-01

    Two strains of a novel basidiomycetous yeast species were isolated from the gut of wood-boring larvae collected in the Baotianman Nature Reserve, the central China. Sequence analysis of the D1/D2 domains of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) regions showed that these yeasts belong to the Bulleromyces clade and formed a cluster together with eleven undescribed Cryptococcus species. The novel species differed from its closest known species, Cryptococcus rajasthanensis, by 3.3 % divergence (15 substitutions and 6 gaps over 630 bases) in the D1/D2 domains, and by 13.4 % divergence (41 substitutions and 27 gaps over 508 bases) in the ITS regions. Physiologically, the fermentation of glucose, galactose, sucrose, trehalose, and raffinose in Durham tubes was observed for the strains of this new yeast. Based on the phenotypical and molecular characteristics presented, the two strains are proposed as a new species, Cryptococcus nanyangensis sp. nov., with the type strain KCY-1(T) (=CICC 1976(T) = CBS 12474(T)).

  2. Microbial communities in sunken wood are structured by wood-boring bivalves and location in a submarine canyon.

    Science.gov (United States)

    Fagervold, Sonja K; Romano, Chiara; Kalenitchenko, Dimitri; Borowski, Christian; Nunes-Jorge, Amandine; Martin, Daniel; Galand, Pierre E

    2014-01-01

    The cornerstones of sunken wood ecosystems are microorganisms involved in cellulose degradation. These can either be free-living microorganisms in the wood matrix or symbiotic bacteria associated with wood-boring bivalves such as emblematic species of Xylophaga, the most common deep-sea woodborer. Here we use experimentally submerged pine wood, placed in and outside the Mediterranean submarine Blanes Canyon, to compare the microbial communities on the wood, in fecal pellets of Xylophaga spp. and associated with the gills of these animals. Analyses based on tag pyrosequencing of the 16S rRNA bacterial gene showed that sunken wood contained three distinct microbial communities. Wood and pellet communities were different from each other suggesting that Xylophaga spp. create new microbial niches by excreting fecal pellets into their burrows. In turn, gills of Xylophaga spp. contain potential bacterial symbionts, as illustrated by the presence of sequences closely related to symbiotic bacteria found in other wood eating marine invertebrates. Finally, we found that sunken wood communities inside the canyon were different and more diverse than the ones outside the canyon. This finding extends to the microbial world the view that submarine canyons are sites of diverse marine life.

  3. 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.

  4. 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.

  5. 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...

  6. The relationship of geophysical measurements to engineering and construction parameters in the Straight Creek Tunnel pilot bore, Colorado

    Science.gov (United States)

    Scott, J.H.; Lee, F.T.; Carroll, R.D.; Robinson, C.S.

    1968-01-01

    Seismic-refraction and electrical-resistivity measurements made along the walls of the Straight Creek Tunnel pilot bore indicate that both a low-velocity and a high-resistivity layer exist in the disturbed rock surrounding the excavation. Seismic measurements were analyzed to obtain the thickness and seismic velocity of rock in the low-velocity layer, the velocity of rock behind the layer and the amplitude of seismic energy received at the detectors. Electrical-resistivity measurements were analyzed to obtain the thickness and electrical resistivity of the high-resistivity layer and the resistivity of rock behind the layer. The electrical resistivity and the seismic velocity of rock at depth, the thickness of rock in the low-velocity layer, and the relative amplitude of seismic energy were correlated against the following parameters, all of which are important in tunnel construction: height of the tension arch, stable vertical rock load, rock quality, rate of construction and cost per foot, percentage of lagging and blocking, set spacing, and type and amount of steel support required, The correlations were statistically meaningful, having correlation coefficients ranging in absolute value from about 0??7 to nearly 1??0. This finding suggests the possibility of predicting parameters of interest in tunnel construction from geophysical measurements made in feeler holes drilled ahead of a working face. Predictions might be based on correlations established either during the early stages of construction or from geophysical surveys in other tunnels of similar design in similar geologic environments. ?? 1968.

  7. 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.

  8. Continuous monitoring and discrete water-quality data from groundwater wells in the Edwards aquifer, Texas, 2014–15

    Science.gov (United States)

    Opsahl, Stephen P.; Musgrove, MaryLynn; Slattery, Richard N.

    2017-01-01

    In cooperation with the San Antonio Water System, continuous and discrete water-quality data were collected from groundwater wells completed in the Edwards aquifer, Texas, 2014-2015. Discrete measurements of nitrate were made by using a nitrate sensor. Precipitation data from two sites in the National Oceanic and Atmospheric Administration Global Historical Climatology Network are included in the dataset. The continuous monitoring data were collected using water quality sensors and include hourly measurements of nitrate, specific conductance, and water level in two wells. Discrete measurements of nitrate, specific conductance, and vertical flow rate were collected from one well site at different depths throughout the well bore.

  9. Mechatronic system for in-bore MRI-guided insertion of needles to the prostate: An in vivo needle guidance accuracy study.

    Science.gov (United States)

    Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Louis, Alyssa S; Davidson, Sean R H; Gertner, Mark; Hlasny, Eugen; Sussman, Marshall S; Fenster, Aaron; Trachtenberg, John

    2015-07-01

    To present our experiences in initial clinical evaluation of a novel mechatronic system for in-bore guidance of needles to the prostate for MRI-guided prostate interventions in 10 patients. We report accuracy of this device in the context of focal laser ablation therapy for localized prostate cancer. An MRI-compatible needle guidance device was developed for transperineal prostate interventions. Ten patients underwent MRI-guided focal laser ablation therapy with device-mediated laser fiber delivery. We recorded needle guidance error and needle delivery time. A total of 37 needle insertions were evaluated. Median needle guidance error was 3.5 mm (interquartile range, 2.1-5.4 mm), and median needle delivery time was 9 min (interquartile range, 6.5-12 min). This system provides a reliable method of accurately aligning needle guides for in-bore transperineal needle delivery to the prostate. © 2014 Wiley Periodicals, Inc.

  10. 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.

  11. Maternal diabetes triggers DNA damage and DNA damage response in neurulation stage embryos through oxidative stress

    Science.gov (United States)

    Dong, Daoyin; Yu, Jingwen; Wu, Yanqing; Fu, Noah; Villela, Natalia Arias; Yang, Peixin

    2015-01-01

    DNA damage and DNA damage response (DDR) in neurulation stage embryos under maternal diabetes conditions are not well understood. The purpose of this study was to investigate whether maternal diabetes and high glucose in vitro induce DNA damage and DDR in the developing embryo through oxidative stress. In vivo experiments were conducted by mating superoxide dismutase 1 (SOD1) transgenic male mice with wild-type (WT) female mice with or without diabetes. Embryonic day 8.75 (E8.75) embryos were tested for the DNA damage markers, phosphorylated histone H2A.X (p-H2A.X) and DDR signaling intermediates, including phosphorylated checkpoint 1 (p-Chk1), phosphorylated checkpoint 2 (p-Chk2), and p53. Levels of the same DNA damage markers and DDR signaling intermediates were also determined in the mouse C17.2 neural stem cell line. Maternal diabetes and high glucose in vitro significantly increased the levels of p-H2A.X. Levels of p-Chk1, p-Chk2, and p53, were elevated under both maternal diabetic and high glucose conditions. SOD1 overexpression blocked maternal diabetes-induced DNA damage and DDR in vivo. Tempol, a SOD1 mimetic, diminished high glucose-induced DNA damage and DDR in vitro. In conclusion, maternal diabetes and high glucose in vitro induce DNA damage and activates DDR through oxidative stress, which may contribute to the pathogenesis of diabetes-associated embryopathy. PMID:26427872

  12. Formation damage due to fines migration and its remedial methods

    Directory of Open Access Journals (Sweden)

    Sabry Kasem Galal

    2016-12-01

    Well testing analysis and well performance analysis were done to detect formation damage and provide an overall measure of formation damage. Laboratory core flood tests had been used to determine the causes, degree, and extent of damage. Scanning electron microscopy (SEM was used to analyze the rock samples used for the core flood test before and after the test. Core flood test had been done to evaluate the effect of acid on improving and curing damaged cores. Matrix acid stimulation on a case study from the studied field was evaluated.

  13. 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.

  14. 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。

  15. 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.

  16. well-being perspective

    African Journals Online (AJOL)

    well-being, namely: self-acceptance, personal growth, purpose in life, positive relations with others .... Sternberg, 2004] identifies the concepts of exploration and commitment from the work of ..... Clinical applications of well-being therapy.

  17. Failure Predictions for DP Steel Cross-die Test Using Anisotropic Damage

    NARCIS (Netherlands)

    Niazi, M.S.; Wisselink, H.H.; Meinders, V.T.; Huetink, J.

    2012-01-01

    The Lemaitre's continuum damage model is well known in the field of damage mechanics. The anisotropic damage model given by Lemaitre is relatively simple, applicable to nonproportional loads and uses only four damage parameters. The hypothesis of strain equivalence is used to map the effective stres

  18. Total well dominated trees

    DEFF Research Database (Denmark)

    Finbow, Arthur; Frendrup, Allan; Vestergaard, Preben D.

    cardinality then G is a total well dominated graph. In this paper we study composition and decomposition of total well dominated trees. By a reversible process we prove that any total well dominated tree can both be reduced to and constructed from a family of three small trees....

  19. 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

  20. 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.