WorldWideScience

Sample records for series barbara hammer1

  1. A body is not a metaphor: Barbara Hammer's X-ray vision.

    Science.gov (United States)

    Osterweil, Ara

    2010-01-01

    This article examines three films by legendary experimental filmmaker Barbara Hammer that deal with the sick, aging, or dying body: Optic Nerve (1985), Sanctus (1990), and A Horse is Not a Metaphor (2008). By analyzing films that do not explicitly confront sexual identity, this article questions the continuing usefulness of the designation "lesbian filmmaker" when considering Hammer's diverse body of work. Tracing the "double consciousness" through which Hammer approaches the body and its construction in patriarchy-particularly in the discourse of medicine-this article argues that Hammer's is a thoroughly corporeal, but not exclusively lesbian, cinema.

  2. California State Waters Map Series: offshore of Santa Barbara, California

    Science.gov (United States)

    Johnson, Samuel Y.; Dartnell, Peter; Cochrane, Guy R.; Golden, Nadine E.; Phillips, Eleyne L.; Ritchie, Andrew C.; Greene, H. Gary; Krigsman, Lisa M.; Kvitek, Rikk G.; Dieter, Bryan E.; Endris, Charles A.; Seitz, Gordon G.; Sliter, Ray W.; Erdey, Mercedes D.; Gutierrez, Carlos I.; Wong, Florence L.; Yoklavich, Mary M.; Draut, Amy E.; Hart, Patrick E.; Conrad, James E.; Cochran, Susan A.; Johnson, Samuel Y.; Cochran, Susan A.

    2013-01-01

    utilized Santa Barbara coastal zone, including Arroyo Burro Beach Park, Leadbetter Beach, East Beach, and “Butterfly Beach.” There are ongoing coastal erosion problems associated with both development and natural processes; between 1933–1934 and 1998, cliff erosion in the map area occurred at rates of about 0.1 to 1 m/yr, the largest amount (63 m) occurring at Arroyo Burro in the western part of the map area. In addition, development of the Santa Barbara Harbor, which began in 1928, lead to shoaling west of the harbor as the initial breakwater trapped sand, as well as to coastal erosion east of the harbor. Since 1959, annual harbor dredging has mitigated at least some of the downcoast erosion problems. The Offshore of Santa Barbara map area lies in the central part of the Santa Barbara littoral cell, which is characterized by littoral drift to the east-southeast. Drift rates have been estimated to be about 400,000 tons/yr at Santa Barbara Harbor. Sediment supply to the western and central parts of the littoral cell, including the map area, is largely from relatively small transverse coastal watersheds. Within the map area, these coastal watersheds include (from east to west) San Ysidro Creek, Oak Creek, Montecito Creek, Sycamore Creek, Mission Creek, Arroyo Burro, and Atascadero Creek. The Ventura and Santa Clara Rivers, the mouths of which are about 40 to 50 km southeast of Santa Barbara, are much larger sediment sources. Still farther east, eastward-moving sediment in the littoral cell is trapped by Hueneme and Mugu Canyons and then transported to the deep-water Santa Monica Basin. The offshore part of the map area consists of a relatively flat and shallow continental shelf, which dips gently seaward (about 0.4° to 0.8°) so that water depths at the 3-nautical-mile limit of California’s State Waters are about 45 m in the east and about 75 m in the west. This part of the Santa Barbara Channel is relatively well protected from large Pacific swells from the north

  3. Correlation of the manual compaction hammer with mechanical hammers for the Marshall method of design for asphaltic concrete.

    Science.gov (United States)

    1964-09-01

    The purpose of this investigation was to establish, through a series of correlations, the compactive effort (number of blows) needed using the mechanical hammers to yield similar physical properties obtained with 75 blows of the manual hammer.

  4. Value-impact analysis for USI A-1, water hammer

    International Nuclear Information System (INIS)

    Serkiz, A.W.

    1983-05-01

    The Unresolved Safety Issue (USI) A-1 deals with safety concerns related to water hammer occurrence in nucler power plants. The staff's concerns were prompted by the increasing frequency of water hammer occurrence in the mid-1970's as new plants were coming on line, and in particular, by the feedwater line rupture at Indian Point No. 2 in 1973 (attributed to water hammer induced by steam-void collapse). Principal concerns were: the potential for inadequate dynamic load design, disablement of safety systems, and the release of radioactivity. The staff's views were set forth in NUREG-0582 and water hammer was designated a USI in 1979

  5. Regulatory analysis for USI A-1, Water Hammer

    International Nuclear Information System (INIS)

    Serkiz, A.W.

    1984-03-01

    This is the staff's regulatory analysis dealing with the resolution of the Unresolved Safety Issue A-1, Water Hammer. This report contains the value-impact analysis for this issue, public comments received, and staff response, or action taken, in response to those comments. The staff's technical findings regarding water hammer in nuclear power plants are contained in NUREG-0927

  6. Water hammer

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    The overall NRC program for the resolution of the water hammer issue is divided into four tasks: water hammer summary reports; revision of CP and OL review procedures; water hammer positions for operating reactors; and water hammer safety studies

  7. Hypothenar hammer syndrome.

    Science.gov (United States)

    Schröttle, Angelika; Czihal, Michael; Lottspeich, Christian; Kuhlencordt, Peter; Nowak, Dennis; Hoffmann, Ulrich

    2015-05-01

    The diagnosis of hypothenar hammer syndrome (HHS) should be considered in the case of hand ischemia in people who occupationally or recreationally use the hypothenar region literally as a “hammer”. Routine diagnostics should consist of physical examination including Allen’s test, acral plethysmography and duplex sonography. According to the prevailing opinion angiography remains the «gold standard test» for establishing the diagnosis of HHS. Early diagnosis allows more effective therapeutic strategies and is important to prevent long-term negative medical sequelae. Several basic principles apply to all patients, for example hand protection and smoking cessation. The optimal treatment options, particularly the indication for surgery, remain controversial due to a lack of sound data from case series or prospective randomized trials.

  8. 1D models for condensation induced water hammer in pipelines

    International Nuclear Information System (INIS)

    Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas

    2013-01-01

    Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

  9. 1D models for condensation induced water hammer in pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas [TUEV NORD SysTec GmbH und Co. KG, Hamburg (Germany)

    2013-03-15

    Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

  10. TPS-HAMMER: improving HAMMER registration algorithm by soft correspondence matching and thin-plate splines based deformation interpolation.

    Science.gov (United States)

    Wu, Guorong; Yap, Pew-Thian; Kim, Minjeong; Shen, Dinggang

    2010-02-01

    We present an improved MR brain image registration algorithm, called TPS-HAMMER, which is based on the concepts of attribute vectors and hierarchical landmark selection scheme proposed in the highly successful HAMMER registration algorithm. We demonstrate that TPS-HAMMER algorithm yields better registration accuracy, robustness, and speed over HAMMER owing to (1) the employment of soft correspondence matching and (2) the utilization of thin-plate splines (TPS) for sparse-to-dense deformation field generation. These two aspects can be integrated into a unified framework to refine the registration iteratively by alternating between soft correspondence matching and dense deformation field estimation. Compared with HAMMER, TPS-HAMMER affords several advantages: (1) unlike the Gaussian propagation mechanism employed in HAMMER, which can be slow and often leaves unreached blotches in the deformation field, the deformation interpolation in the non-landmark points can be obtained immediately with TPS in our algorithm; (2) the smoothness of deformation field is preserved due to the nice properties of TPS; (3) possible misalignments can be alleviated by allowing the matching of the landmarks with a number of possible candidate points and enforcing more exact matches in the final stages of the registration. Extensive experiments have been conducted, using the original HAMMER as a comparison baseline, to validate the merits of TPS-HAMMER. The results show that TPS-HAMMER yields significant improvement in both accuracy and speed, indicating high applicability for the clinical scenario. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  11. Tests of HAMMER (original) and HAMMER-TECHNION systems with critical experiments

    International Nuclear Information System (INIS)

    Santos, A. dos

    1986-01-01

    Performances of the reactor cell codes HAMMER (original) and HAMMER-TECHNION were tested against experimental results of critical benchmarks. The option made was the utilization of consistent methodologies so that only the NIT (Nordheim Integral Technique) was utilized in the HAMMER-TECHNION. All differences encountered in the analysis made with these systems can be attributed to their basic nuclear data library. Five critical benchmarks was utilized on this study. Surprisingly, the performance of the original HAMMER system was betterthan that of the HAMMER-TECHNION. (Author) [pt

  12. Lessons learned from the SONGS Unit 1 water hammer event

    International Nuclear Information System (INIS)

    Chiu, C.

    1987-01-01

    On November 21, 1985, a water hammer event occurred in horizontal feedwater line B at San Onofre Nuclear Generation Site (SONGS) Unit 1. The SONGS Unit 1 is a three-loop pressurized water reactor designed by Westinghouse Electric Corp. The event was initiated by a differential current trip on the bus of auxiliary transformer C. The root cause of the event was a simultaneous failure of five check valves in the feedwater system. Two of them are located downstream of the feedwater pump, and three of them are located further downstream and on the lines to the steam generators. The failure mechanism was determined to be flow-induced vibration, which caused repeated impact between the disk stud and the disk stop. The water hammer occurred in feedwater line B during the refilling of feedwater lines A, B, and C with auxiliary feedwater. The thermal-hydraulic process to initiate the water hammer and the reason that the water hammer only happened in line B have been fully investigated and explained. A root cause analysis after the event was prompted to answer the following two questions: (1) why did these five check valves fail at that time and not in the preceding 15 yr? (2) why did only these five check valves fail? The scope of the root cause analysis involves an investigation of the valve vibration characteristics, plant operation history, and the maintenance history of the valves. The paper answers these two questions, after a brief study of the vibration characteristics of a check valve

  13. Water hammer simulator

    International Nuclear Information System (INIS)

    Sinha, S.K.; Madia, J.; Dixon, S.

    1995-01-01

    The Consolidated Edison Company of New York, Inc. (Con Edison) has constructed a first-of-a-kind water hammer events simulator for use at its training center. The Learning Center, Con Edison's central training facility, intends to use the simulator as an educational tool to demonstrate the various mechanisms of the water hammer phenomenon to power plant designers, engineers and operators. The water hammer phenomenon has been studied extensively for the past 15 years for the nuclear industry. However, the acknowledge of the various water hammer mechanisms and the measures to prevent or mitigate water hammer have not been widely disseminated among the operators of fossil-fueled power plants. Con Edison personnel who operate the various generation stations and the New York City steam distribution systems are expected to benefit from the new simulator. Knowledge gained from interacting with the simulator will be very important in helping the Con Edison prevent, mitigate, or accommodate water hammer at its facilities. The water hammer simulator was fabricated in Con Edison's central machine shop. Details of the design and construction of the simulator were finalized in consultation with Creare, Inc., an engineering research firm, located in Hanover, New Hampshire. The simulator seeks to recreate the essential features of water hammer in steam mines following the buildup of cold (subcooled) water by condensation and steam-water interaction. This paper describes the fabrication, design, testing, and operation of the Con Edison water hammer simulator. A discussion of how Con Edison plans to use the facility at The Learning Center is included

  14. Comparison of Electrostatic Fins with Piezoelectric Impact Hammer Techniques to Extend Impulse Calibration Range of a Torsional Thrust Stand (Preprint)

    Science.gov (United States)

    2011-03-23

    prac- tical max impulse to 1mNs. The newly developed Piezo - electric Impact Hammer (PIH) calibration system over- comes geometric limits of ESC...the fins to behave as part of an LRC circuit which results in voltage oscillations. By adding a resistor in series between the pulse generator and...series resistor as well as the effects of no loading on the pulse generator. III. PIEZOELECTRIC IMPACT HAMMER SYSTEM The second calibration method tested

  15. Ultrasonic rotary-hammer drill

    Science.gov (United States)

    Bar-Cohen, Yoseph (Inventor); Badescu, Mircea (Inventor); Sherrit, Stewart (Inventor); Bao, Xiaoqi (Inventor); Kassab, Steve (Inventor)

    2010-01-01

    A mechanism for drilling or coring by a combination of sonic hammering and rotation. The drill includes a hammering section with a set of preload weights mounted atop a hammering actuator and an axial passage through the hammering section. In addition, a rotary section includes a motor coupled to a drive shaft that traverses the axial passage through the hammering section. A drill bit is coupled to the drive shaft for drilling by a combination of sonic hammering and rotation. The drill bit includes a fluted shaft leading to a distal crown cutter with teeth. The bit penetrates sampled media by repeated hammering action. In addition, the bit is rotated. As it rotates the fluted bit carries powdered cuttings helically upward along the side of the bit to the surface.

  16. Water hammer and cavitational hammer in process plant pipe systems

    International Nuclear Information System (INIS)

    Dudlik, A.; Schoenfeld, S.B.H.; Hagemann, O.; Fahlenkamp, H.

    2003-01-01

    Fast acting valves are often applied for quick safety shut-down of pipelines for liquids and gases in the chemical and petrochemical industry as well as in power plants and state water supplies. The fast deceleration of the liquid leads to water hammer upstream the valve and to cavitational hammer downstream the fast closing valve. The valve characteristics given by manufacturers are usually measured at steady state flow conditions of the liquid. In comparison, the dynamic characteristics depend on the initial liquid velocity, valve closing velocity, the absolute pipe pressure and the pipe geometry. Fraunhofer UMSICHT conducts various test series examining valve dynamic characteristics in order of the dynamic analysis of pressure surges in fast closing processes. Therefore a test rig is used which consists of two pipelines of DN 50 and DN 100 with an approximate length of 230 m each. In this paper the results of performed pressure surge experiments with fast closing and opening valves will be compared to calculations of commercial software programs such as MONA, FLOWMASTER 2. Thus the calculation software for water supply, power plants oil and gas and chemical industry can be permanently improved. (orig.)

  17. Water hammer research in networks

    Directory of Open Access Journals (Sweden)

    Anželika Jurkienė

    2015-10-01

    Full Text Available Formation of water hammer, its consequences and possible protection measures are rarely topics, however the problem is significant. Water hammer can form in water supply and pressurized sewage networks, for various reasons. The article presents short theory of water hammer and methodology for calculation of specific parameters. Research of water hammer was performed in real water supply and sewer networks of country. Simulation of water hammer was carried out by turning on and off water pumps in pumping station. Successful measurement of water hammer depends on accuracy of the measurement equipment, therefore during the research surge wave fluctuations were measured with especially high resolution pressure meters. Detailed analysis of water hammer and selection of protecting equipment hydraulic model of water supply network was created. Protection against water hammer helps to avoid breaking of the water network and extend operation time.

  18. Water hammer research in networks

    OpenAIRE

    Anželika Jurkienė; Mindaugas Rimeika

    2015-01-01

    Formation of water hammer, its consequences and possible protection measures are rarely topics, however the problem is significant. Water hammer can form in water supply and pressurized sewage networks, for various reasons. The article presents short theory of water hammer and methodology for calculation of specific parameters. Research of water hammer was performed in real water supply and sewer networks of country. Simulation of water hammer was carried out by turning on and off water pumps...

  19. OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE - A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING

    Energy Technology Data Exchange (ETDEWEB)

    Arnis Judzis

    2003-01-01

    This document details the progress to date on the ''OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE -- A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING'' contract for the quarter starting October 2002 through December 2002. Even though we are awaiting the optimization portion of the testing program, accomplishments included the following: (1) Smith International participated in the DOE Mud Hammer program through full scale benchmarking testing during the week of 4 November 2003. (2) TerraTek acknowledges Smith International, BP America, PDVSA, and ConocoPhillips for cost-sharing the Smith benchmarking tests allowing extension of the contract to add to the benchmarking testing program. (3) Following the benchmark testing of the Smith International hammer, representatives from DOE/NETL, TerraTek, Smith International and PDVSA met at TerraTek in Salt Lake City to review observations, performance and views on the optimization step for 2003. (4) The December 2002 issue of Journal of Petroleum Technology (Society of Petroleum Engineers) highlighted the DOE fluid hammer testing program and reviewed last years paper on the benchmark performance of the SDS Digger and Novatek hammers. (5) TerraTek's Sid Green presented a technical review for DOE/NETL personnel in Morgantown on ''Impact Rock Breakage'' and its importance on improving fluid hammer performance. Much discussion has taken place on the issues surrounding mud hammer performance at depth conditions.

  20. Treatment of Rigid Hammer-Toe Deformity: Permanent Versus Removable Implant Selection.

    Science.gov (United States)

    Doty, Jesse F; Fogleman, Jason A

    2018-03-01

    Hammer-toe deformities that fail nonoperative treatment can be successfully addressed with proximal interphalangeal joint resection arthroplasty or fusion. The goal of surgery is to eliminate the deformity and rigidly fix the toe in a well-aligned position. Hammer-toe correction procedures can be performed with temporary Kirschner wire (K-wire) fixation for 3 to 6 weeks with high success rates. Pain relief with successful hammer-toe correction approaches 90%; patient satisfaction rates approximate 84%. Although complication rates are rare in most series, there remains a concern regarding exposed temporary K-wire fixation, which has led to the development of multiple permanent internal fixation options. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Skalak's extended theory of water hammer

    NARCIS (Netherlands)

    Tijsseling, A.S.; Lambert, M.F.; Simpson, A.R.; Stephens, M.L.; Vítkovský, J.P.; Bergant, A.

    2008-01-01

    Half a century ago Richard Skalak [see T.C. Skalak, A dedication in memoriam of Dr. Richard Skalak, Annual Review of Biomedical Engineering 1 (1999) 1–18] published a paper with the title "An extension of the theory of water hammer" [R. Skalak, An Extension of the Theory of Water Hammer, PhD Thesis,

  2. Validity and Reliability of the Cycleops Hammer Cycle Ergometer.

    Science.gov (United States)

    Lillo-Bevia, José R; Pallarés, Jesús G

    2017-11-28

    To validate the new drive indoor trainer Hammer designed by Cycleops®. Eleven cyclists performed 44 randomized and counterbalanced graded exercise tests (100-500W), at 70, 85 and 100 rev.min -1 cadences, in seated and standing positions, on 3 different Hammer units, while a scientific SRM system continuously recorded cadence and power output data. No significant differences were detected between the three Hammer devices and the SRM for any workload, cadence, or pedalling condition (P value between 1.00 and 0.350), except for some minor differences (P 0.03 and 0.04) found in the Hammer 1 at low workloads, and for Hammer 2 and 3 at high workloads, all in seated position. Strong ICCs were found between the power output values recorded by the Hammers and the SRM (≥0.996; P=0.001), independently from the cadence condition and seated position. Bland-Altman analysis revealed low Bias (-5.5-3.8) and low SD of Bias (2.5-5.3) for all testing conditions, except marginal values found for the Hammer 1 at high cadences and seated position (9.6±6.6). High absolute reliability values were detected for the 3 Hammers (150-500W; CVreliable device to drive and measure power output in cyclists, providing an alternative to larger and more expensive laboratory ergometers, and allowing cyclists to use their own bicycle.

  3. OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE - A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING

    Energy Technology Data Exchange (ETDEWEB)

    Alan Black; Arnis Judzis

    2003-01-01

    Progress during current reporting year 2002 by quarter--Progress during Q1 2002: (1) In accordance to Task 7.0 (D. No.2 Technical Publications) TerraTek, NETL, and the Industry Contributors successfully presented a paper detailing Phase 1 testing results at the February 2002 IADC/SPE Drilling Conference, a prestigious venue for presenting DOE and private sector drilling technology advances. The full reference is as follows: IADC/SPE 74540 ''World's First Benchmarking of Drilling Mud Hammer Performance at Depth Conditions'' authored by Gordon A. Tibbitts, TerraTek; Roy C. Long, US Department of Energy, Brian E. Miller, BP America, Inc.; Arnis Judzis, TerraTek; and Alan D. Black, TerraTek. Gordon Tibbitts, TerraTek, will presented the well-attended paper in February of 2002. The full text of the Mud Hammer paper was included in the last quarterly report. (2) The Phase 2 project planning meeting (Task 6) was held at ExxonMobil's Houston Greenspoint offices on February 22, 2002. In attendance were representatives from TerraTek, DOE, BP, ExxonMobil, PDVSA, Novatek, and SDS Digger Tools. (3) PDVSA has joined the advisory board to this DOE mud hammer project. PDVSA's commitment of cash and in-kind contributions were reported during the last quarter. (4) Strong Industry support remains for the DOE project. Both Andergauge and Smith Tools have expressed an interest in participating in the ''optimization'' phase of the program. The potential for increased testing with additional Industry cash support was discussed at the planning meeting in February 2002. Progress during Q2 2002: (1) Presentation material was provided to the DOE/NETL project manager (Dr. John Rogers) for the DOE exhibit at the 2002 Offshore Technology Conference. (2) Two meeting at Smith International and one at Andergauge in Houston were held to investigate their interest in joining the Mud Hammer Performance study. (3) SDS Digger Tools (Task 3

  4. Evaluation of water-hammer experience in nuclear power plants. Technical findings relevant to Unresolved Safety Issue A-1

    International Nuclear Information System (INIS)

    Serkiz, A.W.

    1983-05-01

    This report summarizes key technical findings relevant to the Unresolved Safety Issue A-1, Water Hammer. These findings were derived from studies of reported water hammer occurrences and underlying causes and provide key insights into means to minimize or eliminate further water hammer occurrences. It should also be noted that this report does not represent a substitute for current rules and regulations

  5. Evaluation of water hammer occurrence in nuclear power plants: technical findings relevant to unresolved safety issue A-1

    International Nuclear Information System (INIS)

    1984-03-01

    This report, which includes responses to public comments, summarizes key technical findings relevant to the Unresolved Safety Issue A-1, Water Hammer. These findings were derived from studies of reported water hammer occurrences and underlying causes and provide key insights into means to minimize or eliminate further water hammer occurrences. This report does not represent a substitute for current rules and regulations

  6. Maximum Water Hammer Sensitivity Analysis

    OpenAIRE

    Jalil Emadi; Abbas Solemani

    2011-01-01

    Pressure waves and Water Hammer occur in a pumping system when valves are closed or opened suddenly or in the case of sudden failure of pumps. Determination of maximum water hammer is considered one of the most important technical and economical items of which engineers and designers of pumping stations and conveyance pipelines should take care. Hammer Software is a recent application used to simulate water hammer. The present study focuses on determining significance of ...

  7. An analysis of the relationship between the linear hammer speed and the thrower applied forces during the hammer throw for male and female throwers.

    Science.gov (United States)

    Brice, Sara M; Ness, Kevin F; Rosemond, Doug

    2011-09-01

    The purpose of this study was to investigate the relationship between the cable force and linear hammer speed in the hammer throw and to identify how the magnitude and direction of the cable force affects the fluctuations in linear hammer speed. Five male (height: 1.88 +/- 0.06 m; body mass: 106.23 +/- 4.83 kg) and five female (height: 1.69 +/- 0.05 m; body mass: 101.60 +/- 20.92 kg) throwers participated and were required to perform 10 throws each. The hammer's linear velocity and the cable force and its tangential component were calculated via hammer head positional data. As expected, a strong correlation was observed between decreases in the linear hammer speed and decreases in the cable force (normalised for hammer weight). A strong correlation was also found to exist between the angle by which the cable force lags the radius of rotation at its maximum (when tangential force is at its most negative) and the size of the decreases in hammer speed. These findings indicate that the most effective way to minimise the effect of the negative tangential force is to reduce the size of the lag angle.

  8. Reliability of the input admittance of bowed-string instruments measured by the hammer method.

    Science.gov (United States)

    Zhang, Ailin; Woodhouse, Jim

    2014-12-01

    The input admittance at the bridge, measured by hammer testing, is often regarded as the most useful and convenient measurement of the vibrational behavior of a bowed string instrument. However, this method has been questioned, due especially to differences between human bowing and hammer impact. The goal of the research presented here is to investigate the reliability and accuracy of this classic hammer method. Experimental studies were carried out on cellos, with three different driving conditions and three different boundary conditions. Results suggest that there is nothing fundamentally different about the hammer method, compared to other kinds of excitation. The third series of experiments offers an opportunity to explore the difference between the input admittance measuring from one bridge corner to another and that of single strings. The classic measurement is found to give a reasonable approximation to that of all four strings. Some possible differences between the hammer method and normal bowing and implications of the acoustical results are also discussed.

  9. Muscle fibre type composition and body composition in hammer throwers.

    Science.gov (United States)

    Terzis, Gerasimos; Spengos, Konstantinos; Kavouras, Stavros; Manta, Panagiota; Georgiadis, Giorgos

    2010-01-01

    Aim of the present study was to describe the muscle fibre type composition and body composition of well-trained hammer throwers. Six experienced hammer throwers underwent the following measurements: one repetition maximum in squat, snatch, and clean, standing broad jump, backward overhead shot throw and the hammer throw. Dual x-ray absorptiometry was used for body composition analysis. Fibre type composition and cross sectional area was determined in muscle biopsy samples of the right vastus lateralis. Eight physical education students served as a control group. One repetition maximum in squat, snatch and clean for the hammer throwers was 245 ± 21, 132 ± 13 and 165 ± 12kg, respectively. Lean body mass was higher in hammer throwers (85.9 ± 3. 9kg vs. 62.7 ± 5.1kg (p hammer throwers and 51 ± 8% in the control group (p Hammer throwers had significantly larger type IIA fibres (7703 ± 1171 vs. 5676 ± 1270μm(2), p Hammer throwing performance correlated significantly with lean body mass (r = 0.81, p hammer throwers have larger lean body mass and larger muscular areas occupied by type II fibres, compared with relatively untrained subjects. Moreover, it seems that the enlarged muscle mass of the hammer throwers contributes significantly to the hammer throwing performance. Key pointsWell-trained hammer throwers had increased lean body mass, higher type IIA muscle fibres cross sectional areas, as well as higher bone mineral density, compared to controls.Increased lean body mass was closely related with hammer throwing performance.The relative high percentage of type IIX muscle fibres in vastus lateralis in hammer throwers warrants further investigation.

  10. Dynamic Analysis of Hammer Mechanism "Twin Hammer" of Impact Wrench

    Science.gov (United States)

    Konečný, M.; Slavík, J.

    This paper describes function of the hammer mechanism "Twin hammer" the impact wrench, calculation of dynamic forces exerted on the mechanism and determining the contact pressures between the parts of the mechanism. The modelling of parts was performed in system Pro ENGINEER—standard. The simulation and finding dynamic forces was performed in advanced module Pro ENGINEER—mechanism design and finding contacts pressures in modul Pro ENGENEER—mechanica.

  11. High-tech hammer : BBJ Tools transforms the traditional fluid hammer into a revolutionary drilling tool

    Energy Technology Data Exchange (ETDEWEB)

    Byfield, M.

    2010-12-15

    This article described BBJ Tools' patent-pending fluid hammer that enhances drilling rate of penetration. The technology was awarded the 2010 winner for best drilling technology for a company with fewer than 100 employees. The fluid hammer features several improvements in terms of maintaining drill-bit integrity, steering ability, and operating flexibility. The hammer incorporates a positive displacement motor and adjustable housing that uniquely allow the driller to steer the drill bit. The fluid hammer works with both polycrystalline diamond compact bits and roller cones. The unique weight-to-bit-transfer design allows the operator to have diversified percussion control. More weight on the bit results in more force, and hammering stops when weight is taken off the bit. The major components of the mud motor are incorporated into the fluid hammer, allowing the tool to compete in every application in which a mud motor is used. The percussion mechanism transmits left-hand reactive torque to the housing. The rate of penetration is substantially better than other similar tools on the market. 2 figs.

  12. An evaluation of water hammer in nuclear power plants

    International Nuclear Information System (INIS)

    Serkiz, A.

    1983-01-01

    Water hammer can occur as a result of to steam-void collapse, steam-driven slugs of water, pump startup into voided lines, and inadverdent closures of valves; the result is large hydraulic pressure loads. Since 1968, about 150 water hammer events have been reported in U.S. nuclear power plants; damage has been confined to pipe hangers and snubbers. The increase in reported water hammer events in the 1970s led to the designation of water hammer as Unresolved Safety Issue A-1 in 1979. Since the mid-1970s reported occurrences and their underlying phenomena have been studied, and corrective design and operational measures have been implemented. This paper presents the results of generic evaluations of water hammer occurrence and reported damage and sets forth technical findings. These findings indicate that good design practices and operational procedures can minimize the occurrence of water hammer

  13. Water Hammer Analysis using RELAP5/MOD 3.3 for Yonggwang Nuclear Power Unit 1 and 2 Blowdown System

    International Nuclear Information System (INIS)

    Lee, Sang Il; Kim, Hea Zoo; Chu, Jung Ho; Ahn, Se Hong; Jung, Chang Ho

    2010-01-01

    Water hammer can be defined as a rapid pressure step occurring in the liquid in a closed pipe caused by a sudden change in the liquid velocity. This pressure acts for a period which is twice the transit time of sonic wave in the pipe. Generally, water hammer can occur in any thermal-hydraulic systems like nuclear power plant and is extremely dangerous for nuclear power plant piping system since, if the pressure induced exceeds the pressure range of the pipe given by the manufacturer, it can lead to the failure of the piping system integrity. For Yonggwang nuclear power unit 1 and 2, water hammer occurred repeatedly on the outlet piping of regenerative heat exchanger of steam generator blowdown system. Thus, design modification was performed to prevent the water hammer and the analysis of effect on water hammer before and after design modification was performed to verify the validity of the design modification

  14. Review of two-phase water hammer

    International Nuclear Information System (INIS)

    Beuthe, T.G.

    1997-01-01

    In a thermalhydraulic system like a nuclear power plant, where steam and water mix and are used to transport large amounts of energy, there is a potential to create two-phase water hammer. Large water hammer pressure transients are a threat to piping integrity and represent an important safety concern. Such events may cause unscheduled plant down time. The objective of this review is to provide a summary of the information on two-phase water hammer available in the open literature with particular emphasis on water hammer occurrences in nuclear power plants. Past reviews concentrated on studies concerned with preventing water hammer. The present review focuses on the fundamental experimental, analytical, and modelling studies. The papers discussed here were chosen from searches covering up to July 1993. (author)

  15. Water hammers in direct contact heater systems

    International Nuclear Information System (INIS)

    Uffer, R.

    1983-01-01

    This paper discusses the causes and mitigation or prevention of water hammers occurring in direct contact heaters and their attached lines. These water hammers are generally caused by rapid pressure reductions in the heaters or by water lines not flowing full. Proper design and operating measures can prevent or mitigate water hammer occurrence. Water hammers often do not originate at the areas where damage is noted

  16. Observations on steam generator water hammer

    International Nuclear Information System (INIS)

    Hildebrandt, P.C.

    1979-01-01

    The present state of understanding of water hammer phenomena apparently does not permit analytically predicting the occurrence or consequence of water hammer, with any confidence, or conclusively evaluating the benefit associated with any particular action taken to ameliorate an existing or potential water hammer problem. Features or fixes are incorporated based on overwhelming the problem, and trial and error

  17. Optimization of Mud Hammer Drilling Performance--A Program to Benchmark the Viability of Advanced Mud Hammer Drilling

    Energy Technology Data Exchange (ETDEWEB)

    Arnis Judzis

    2006-03-01

    Operators continue to look for ways to improve hard rock drilling performance through emerging technologies. A consortium of Department of Energy, operator and industry participants put together an effort to test and optimize mud driven fluid hammers as one emerging technology that has shown promise to increase penetration rates in hard rock. The thrust of this program has been to test and record the performance of fluid hammers in full scale test conditions including, hard formations at simulated depth, high density/high solids drilling muds, and realistic fluid power levels. This paper details the testing and results of testing two 7 3/4 inch diameter mud hammers with 8 1/2 inch hammer bits. A Novatek MHN5 and an SDS Digger FH185 mud hammer were tested with several bit types, with performance being compared to a conventional (IADC Code 537) tricone bit. These tools functionally operated in all of the simulated downhole environments. The performance was in the range of the baseline ticone or better at lower borehole pressures, but at higher borehole pressures the performance was in the lower range or below that of the baseline tricone bit. A new drilling mode was observed, while operating the MHN5 mud hammer. This mode was noticed as the weight on bit (WOB) was in transition from low to high applied load. During this new ''transition drilling mode'', performance was substantially improved and in some cases outperformed the tricone bit. Improvements were noted for the SDS tool while drilling with a more aggressive bit design. Future work includes the optimization of these or the next generation tools for operating in higher density and higher borehole pressure conditions and improving bit design and technology based on the knowledge gained from this test program.

  18. A new production technique for wear resistant ring-hammers

    Directory of Open Access Journals (Sweden)

    Li Shifeng

    2011-11-01

    Full Text Available Based on a great number of laboratory experiments, a new technique has been developed for producing wear resistant ring-hammers. In this technology, lost foam casting with iron sand was combined to make mold; a special alloy was used to inoculate the molten steel, and proper heat treatment was used to further improve mechanical properties of wear resistant ring-hammers. The influence of this new production technology on the microstructure and mechanical properties of wear resistant ring-hammers was studied. Results show that iron sand molding, having the inherent characteristic of sand molding, changes the type of metallic compounds, refines crystal grains and increases the fineness of microstructure. Practical experience verified that the properties of the ring-hammers produced with this new technique are as follows: tensile strength (Rm 720 MPa, impact toughness (ak > 210 J•cm-2 and hardness > 200 HB. After water quenching from 1,080℃ (holding for 4 h and tempering at 320℃ for 3 h, the best wear resistance is obtained, and the wear resistance is 1.6 times higher than that of common high manganese ring-hammers.

  19. Effect of hammer mass on upper extremity joint moments.

    Science.gov (United States)

    Balendra, Nilanthy; Langenderfer, Joseph E

    2017-04-01

    This study used an OpenSim inverse-dynamics musculoskeletal model scaled to subject-specific anthropometrics to calculate three-dimensional intersegmental moments at the shoulder, elbow and wrist while 10 subjects used 1 and 2 lb hammers to drive nails. Motion data were collected via an optoelectronic system and the interaction of the hammer with nails was recorded with a force plate. The larger hammer caused substantial increases (50-150%) in moments, although increases differed by joint, anatomical component, and significance of the effect. Moment increases were greater in cocking and strike/follow-through phases as opposed to swinging and may indicate greater potential for injury. Compared to shoulder, absolute increases in peak moments were smaller for elbow and wrist, but there was a trend toward larger relative increases for distal joints. Shoulder rotation, elbow varus-valgus and pronation-supination, and wrist radial-ulnar deviation and rotation demonstrated large relative moment increases. Trial and phase durations were greater for the larger hammer. Changes in moments and timing indicate greater loads on musculoskeletal tissues for an extended period with the larger hammer. Additionally, greater variability in timing with the larger hammer, particularly for cocking phase, suggests differences in control of the motion. Increased relative moments for distal joints may be particularly important for understanding disorders of the elbow and wrist associated with hammer use. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Meshless computation of water hammer

    NARCIS (Netherlands)

    Tijsseling, A.S.; Bergant, A.

    2007-01-01

    Water hammer concerns the generation, propagation, reflection and damping of pressure waves in liquidfilled pipe systems. The numerical simulation of water-hammer events is usually based on one-dimensional mathematical models. Two equations representing the conservation of mass and momentum govern

  1. Linear or Rotary Actuator Using Electromagnetic Driven Hammer as Prime Mover

    Science.gov (United States)

    Paine, Jeffrey S. N. (Inventor); Smith, Byron F. (Inventor); Sesler, Joshua J. (Inventor); Paine, Matthew T. (Inventor); McMahan, Bert K. (Inventor); McMahan, Mark C. (Inventor)

    2018-01-01

    We claim a hammer driven actuator that uses the fast-motion, low-force characteristics of an electro-magnetic or similar prime mover to develop kinetic energy that can be transformed via a friction interface to produce a higher-force, lower-speed linear or rotary actuator by using a hammering process to produce a series of individual steps. Such a system can be implemented using a voice-coil, electro-mechanical solenoid or similar prime mover. Where a typical actuator provides limited range of motion or low force, the range of motion of a linear or rotary impact driven motor can be configured to provide large displacements which are not limited by the characteristic dimensions of the prime mover.

  2. The Hammer-and-Nail Phenomenon in Mathematics Education

    Science.gov (United States)

    Lim, Kien H.

    2012-01-01

    This paper uses the hammer-and-nail metaphor to highlight the rigidity and impulsiveness that can be found in student mathematical behaviour. The hammer-and-nail phenomenon can be attributed to two plausible causes: (1) the way the human mind works; and (2) the way mathematics is traditionally taught in school. In this paper, the following aspects…

  3. Two-phase water hammer in nuclear power plants

    International Nuclear Information System (INIS)

    Kim, J.H.

    1987-01-01

    Water hammer events keep recurring in nuclear power plants. In the mid-1970s, water hammer was designated to be an unresolved safety issue (USI A-1) due to its high frequency of occurrence and the severity of the attendant damages. Between 1969 and 1981, a significant number of water hammer incidents (more than 12 events per year) involving BWRs and PWRs have been reported and evaluated. After intensive evaluations of the events, in late 1983, the U.S. Nuclear Regulatory Commission staff concluded that water hammer was not a serious contributor to the degradation of plant safety and it has been taken off the list of the unresolved safety issues. The frequency decreased to around 11 events per year between 1981 and 1985. Nevertheless, 11 events per year are still unacceptable high, especially in light of the financial losses caused by most events. Some events are not required to be reported. The number of the unreported events are estimated to be five to ten times as many as the reported events. The implication is that water hammer in nuclear power plants still needs attention and is a problem that has not been fundamentally resolved

  4. Water hammer in nuclear power plants

    International Nuclear Information System (INIS)

    1979-07-01

    In the past few years, licensees of operating reactors have reported a large number of water hammer events during commercial operation. Most of these events resulted in damage to piping supports and restraints. A few cases involved small cracks or ruptures in feedwater systems. As a result, in 1977 the NRC staff initiated a review of reported water hammer events and of the potential for occurrence of water hammer in all fluid systems that could have an impact on plant safety. The objectives of the review were to identify the causes of water hammer events that could affect reactor safety and to recommend further staff actions needed to reduce the likelihood of such events

  5. 21 CFR 890.1450 - Powered reflex hammer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered reflex hammer. 890.1450 Section 890.1450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hammer. (a) Identification. A powered reflex hammer is a motorized device intended for medical purposes...

  6. Electromagnetic Hammer for Metalworking

    Science.gov (United States)

    Anderson, S. A.; Brunet, F.; Dowd, A.; Durham, R.; Ezell, J.; Gorr, G.; Hartley, D.; Jackson, F.; Marchand, J.; Macfarlane, W.; hide

    1986-01-01

    High eddy currents apply pressure for cold-forming. Coil housing constructed for mechanical strength to hold coil against magnetic force, to maintain electrical contact with coil ends, and to maintain insulation between coil turns. Drilled holes placed to facilitate release of bubbles during potting. In contrast with mechanical hammers, electromagnetic hammer requires no dynamic material contact with workpiece; consequently, produces almost no change in metal grain structure.

  7. Screening reactor steam/water piping systems for water hammer

    International Nuclear Information System (INIS)

    Griffith, P.

    1997-09-01

    A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greater than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made

  8. Automated Grid Monitoring for LHCb through HammerCloud

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    The HammerCloud system is used by CERN IT to monitor the status of the Worldwide LHC Computing Grid (WLCG). HammerCloud automatically submits jobs to WLCG computing resources, closely replicating the workflow of Grid users (e.g. physicists analyzing data). This allows computation nodes and storage resources to be monitored, software to be tested (somewhat like continuous integration), and new sites to be stress tested with a heavy job load before commissioning. The HammerCloud system has been in use for ATLAS and CMS experiments for about five years. This summer's work involved porting the HammerCloud suite of tools to the LHCb experiment. The HammerCloud software runs functional tests and provides data visualizations. HammerCloud's LHCb variant is written in Python, using the Django web framework and Ganga/DIRAC for job management.

  9. On the prediction of impact noise, V: The noise from drop hammers

    Science.gov (United States)

    Richards, E. J.; Carr, I.; Westcott, M.

    1983-06-01

    In earlier papers in this series, the concepts of "acceleration" and "ringing" noise have been studied in relation to impact machines, and values of radiation efficiency have been obtained for the various types of structural components. In the work reported in this paper the predicted and measured noise radiation from a drop hammer, both in full-scale and in {1}/{3}- scale model form, were examined. It is found that overall noise levels ( Leq per event) can be predicted from vibration measurements to within ± 1·5 dB, and to within ±2·5 dB in one-third octave bands. In turn this has permitted noise reduction techniques to be examined by studies of local component vibration levels rather than overall noise, a method which provides considerable enlightenment at the design stage. It is shown that on one particular drop hammer, the noise energy is shared surprisingly uniformly over four or five sources, and that when these have been reduced, the overall noise reduction is severely limited by the "acceleration" noise from the "tup" or "hammer" itself. As this is difficult to eliminate without a basic change in forging technology, it follows that "tup" enclosure or modification of the sharpness of the final "hard" impact are the only means available for any serious noise reduction. Also indicated is the reliability of using model techniques, suitably scaled in frequency and impulse magnitude, in developing machinery with impact characteristics.

  10. Experimental investigation of the piano hammer-string interaction.

    Science.gov (United States)

    Birkett, Stephen

    2013-04-01

    Experimental techniques for investigating the piano hammer-string interaction are described. It is argued that the accuracy, consistency, and scope of conclusions of previous studies can be compromised by limitations of the conventional methods relating to key inputs; physical distortion; numerical distortion, particularly when differentiation or integration of measured signals is used to derive primary response variables; contact identification; and synchronization issues. These problems are discussed, and experimental methods that have been devised to avoid them are described and illustrated by detailed results from a study of the hammer-string interaction in a vertical piano. High resolution displacements are obtained directly by non-contact high-speed imaging and quantitative motion tracking. The attention focused on achieving very accurate and consistent temporal and spatial alignment, including the objective procedure used for contact identification, allows meaningful comparisons of responses from separate tests. String motion at the strike point and on each side of it, as well as hammer motion, is obtained for eight dynamic levels from 1.06 to 2.98 m/s impact velocity. Detailed observations of the force-compression behavior of the hammer interacting with real strings are presented. The direct effects of hammer shank deflection and agraffe string pulses on the interaction are also highlighted.

  11. Reconstruction of piano hammer force from string velocity.

    Science.gov (United States)

    Chaigne, Antoine

    2016-11-01

    A method is presented for reconstructing piano hammer forces through appropriate filtering of the measured string velocity. The filter design is based on the analysis of the pulses generated by the hammer blow and propagating along the string. In the five lowest octaves, the hammer force is reconstructed by considering two waves only: the incoming wave from the hammer and its first reflection at the front end. For the higher notes, four- or eight-wave schemes must be considered. The theory is validated on simulated string velocities by comparing imposed and reconstructed forces. The simulations are based on a nonlinear damped stiff string model previously developed by Chabassier, Chaigne, and Joly [J. Acoust. Soc. Am. 134(1), 648-665 (2013)]. The influence of absorption, dispersion, and amplitude of the string waves on the quality of the reconstruction is discussed. Finally, the method is applied to real piano strings. The measured string velocity is compared to the simulated velocity excited by the reconstructed force, showing a high degree of accuracy. A number of simulations are compared to simulated strings excited by a force derived from measurements of mass and acceleration of the hammer head. One application to an historic piano is also presented.

  12. Studi Numerik Variasi Pemilihan Gas Accumulator Untuk Pencegahan Water Hammer Pada Sistem Perpipaan Sepanjang 1 Kilometer dan Debit Aliran 800 GPM

    Directory of Open Access Journals (Sweden)

    Anindika Bagus Pradana

    2013-09-01

    Full Text Available Sistem jaringan perpipaan sangat penting dalam menunjang produksi pada bidang industri. Jaringan perpipaan mengalami beberapa fenomena seperti distribusi fluida dan water hammer. Water hammer sering terjadi di daerah discharge pompa saat pengoperasian dan gagalnya beroperasinya pompa. Water hammer dapat merusak jaringan perpipaan. Fenomena water hammer dapat terjadi hampir di setiap sistem instalasi perpipaan. Fenomena ini mempunyai dampak buruk apabila sistem perpipaan tersebut tidak memperhatikan akibat dari water hammer. Fenomena dalam sistem perpipaan mempunyai dampak negatif dengan selang waktu tertentu, water hammer adalah fenomena dimana dampak yang ditimbulkan terjadi seketika itu juga. Penanggulangan yang tidak tepat terhadap dampak tersebut dapat mengakibatkan instalasi tersebut harus dimatikan (shutdown. Pada simulasi ini digunakan sistem instalasi perpipaan dengan panjang 1 kilometer dan debit aliran 800 gpm.Pada sistem instalasi ini memiliki rangkaian pompa tunggal yang dilengkapi dengan gas accumulator di sisi discharge pompa. Ketika terjadi perubahan flow rate yang menyebabkan pompa beroprasi atau gagal beroprasi akan menimbulkan fenomena water hammer.Penelitian dilakukan secara numerik menggunakan software AFT Impulse 4.0. Water hammer dapat diminimalisi dengan memasang gas accumulator pada daerah dekat discharge pompa. Variasi gas accumulator adalah gas accumulator merk NOK tipe AT 175-20 dengan volume maksimum 20 liter, tipe AT 210-60 dengan volume maksimum 60 liter dan tipe AT 230-120 dengan volume maksimum 100 liter. Hasil yang didapatkan pada simulasi menunjukan pada jarak 4 meter dari rumah pompa masing-masing P max dan P min  untuk sistem perpipaan dengan simulasi proses trip pompa tanpa proteksi water hammer adalah 1729 Kpa dan 381 Kpa, untuk sistem perpipaan dengan gas accumulator volume setting 20 liter adalah 1228 Kpa dan 927 Kpa, untuk sistem perpipaan dengan gas accumulator volume setting 60 liter adalah 1161 Kpa

  13. Barbara Trenholm | IDRC - International Development Research ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Barbara is a professor emerita at the University of New Brunswick (UNB). She holds an Institute of Corporate Directors designation (ICD.D), and a FCPA and FCA with Chartered Professional Accountants (CPA) New Brunswick. Barbara is currently a member of the Plaza Retail REIT board of trustees and the New Brunswick ...

  14. Water-hammer prevention, mitigation, and accommodation: a perspective

    International Nuclear Information System (INIS)

    Kim, J.H.

    1987-01-01

    The purpose of this paper is to present an industry perspective on water hammer, revisit the issues, and renew interest in this area with aim to prevent, mitigate, and accommodate water hammer. Water hammer keeps recurring in nuclear power plants and damages plant components and impacts on plant operations and availability through forced outages of plants. The implication is that water hammer in nuclear power plants still needs attention and is a problem that has not been fundamentally resolved. The paper displays statistics of the reported water hammer events between 1969 and 1985. The consequences of these water hammer events were: pipe support damage (hangers, anchors, and snubbers), 60%; component damage (piping, pumps, and valves), 17%; reactor trip, 10%; and plant shutdown, 7%. Reactor trips and plant shutdowns account for 17% of the event consequences. At the request of the nuclear utility industry, a workshop on water hammer was sponsored by the Electric Power Research Institute (EPRI), with cosponsorship from Northeast Utility Service Company, Yankee Atomic Electric Company, and Boston Edison Company, which drew some 90 specialists representing 28 utility companies as well as other nuclear industry, academia, and the NRC. The workshop recommendations are summarized

  15. Rannus mängitakse suvel Barbara lugu

    Index Scriptorium Estoniae

    2007-01-01

    Augustis on Rannus näitlejate ja näitejuhtide suvekool, mille tipphetk on ühine vabaõhuetendus "Barbara lugu", lavastajaks Jüri Lumiste. Artiklis ka lühidalt Barbara von Tiesenhuseni, kes oli Rannu lossi Tiesenhusenite 12 lapsest noorim, saatusest

  16. Simulation of water hammer experiments using RELAP5 code

    International Nuclear Information System (INIS)

    Kaliatka, A.; Vaisnoras, M.

    2005-01-01

    The rapid closing or opening of a valve causes pressure transients in pipelines. The fast deceleration of the liquid results in high pressure surges upstream the valve, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increases. This phenomenon is called water hammer. The intensity of water hammer effects will depend upon the rate of change in the velocity or momentum. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the thermal-hydraulic system since, if the pressure induced exceeds the pressure range of a pipe given by the manufacturer, it can lead to the failure of the pipeline integrity. Due to its potential for damage of pipes, water hammer has been a subject of study since the middle of the nineteenth century. Many theoretical and experimental investigations were performed. The experimental investigation of the water hammer tests performed at Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) [1] and Cold Water Hammer experiment performed by Forschungszentrum Rossendorf (CWHTF) [2] should be mentioned. The UMSICHT facility in Oberhausen was modified in order to simulate a piping system and associated supports that are typical for a nuclear power plant [3]. The Cold water hammer experiment is interesting and instructive because it covers a wide spectrum of particularities. One of them is sub-cooled water interaction with condensing steam at the closed end of the vertical pipe at room temperature and corresponding saturation pressure [4]. In the paper, the capabilities of RELAP5 code to correctly represent the water hammer phenomenon are presented. Paper presents the comparison of RELAP5 calculated and measured at UMSICHT and CWHTF test facilities pressure transient values after the fast closure (opening) of valves. The analyses of rarefaction wave travels inside the pipe and condensation of vapour bubbles in the liquid column

  17. Barbara Cooney.

    Science.gov (United States)

    Horne, Jackie C.

    2000-01-01

    Profiles the life/work of the award winning picture-book author-illustrator Barbara Cooney. Includes her early development as an artist; early attempts at the picture-book form; experimentation with different media: watercolor, pen/ink with wash, charcoal, acrylics, pastels, and collage; later work that draws upon folk-art traditions; her love of…

  18. Comparison of Piezosurgery and Hammer-Chisel in Endoscopic Dacryocystorhinostomy.

    Science.gov (United States)

    Çukurova, Ibrahim; Bulğurcu, Suphi; Arslan, Ilker Burak; Dikilitaş, Bünyamin

    2018-05-08

    In this study, we compared the advantages and disadvantages of piezosurgery and hammer-chisel used in endoscopic dacryocystorhinostomy (EDCR). Between January 2012 and January 2016, 10 women and 8 men in whom piezosurgery was used (group 1) and 11 women and 7 men in whom hammer-chisel was used (group 2) during EDCR operations were compared retrospectively. Recurrence, operation time, postoperative bleeding, and operative cost were evaluated in patients who were followed for an average of 11.8 months. In addition, visual analogue scale (VAS) was used to assess pain at 6 hours postoperatively. No recurrence was observed in group 1, but recurrence was observed in 2 patients in group 2 (P = 0.685). There was no postoperative bleeding in both groups. The mean duration of operation was 30.6 ± 8.2 minutes in group 1 and 46.8 ± 9.5 minutes in group 2 (P = 0.038). The VAS score in group 1 was 2.7 ± 1.4 and the VAS score in group 2 was 5.8 ± 2.2 (P = 0.01). Piezosurgery costs an additional $325 for each patient while the use of the hammer-chisel does not incur additional costs. Piezosurgery causes shorter operation time, less recurrence, and less pain when compared with hammer-chisel.

  19. Water-hammer experimental set-up and water-hammer experimental study for new types of check valve applied to PWR

    International Nuclear Information System (INIS)

    Liu Hanxun.

    1985-01-01

    This paper describes a self-designed constant temperature water-hammer shock test rig with stainless steel loop in which deionized water is used as working medium. To conduct water-hammer shock simulation tests for the countercurrent phenomenon occurred in the process of shutting, stopping, parallelling and switching the coolant loops of nuclear reactor, a specially designed four-way switching valve and its pneumatic mechanism are used. Water-hammer experimental study is performed for two types of PWR's nonshock check valve with diameter of 150 mm and 200 mm simultaneously. Transient performance of the shock waves, magnitude of their peaks and durations of their fluctuation, is obtained. Some analyses for existing calculational method on water-hammer are made

  20. Water hammer in USA nuclear power plants and it's evaluation

    International Nuclear Information System (INIS)

    Liu Shuqian.

    1987-01-01

    The results of evaluations about the water hammer events in USA nuclear power plants in recent years are summarily reported. The evaluations included underlying causes and frequency of water hammer events, damages incurred and systems affected. Through the evaluations about water hammer events and on the basis of past operation experiences in nuclear power plants, the design and operational modifications to prevent or mitigate water hammer events were presented. The NRC's current opinions relating to the water hammer problems are summarized, the importance of water hammer events for nuclear power plants construction in China is indicated

  1. Analysis of water hammer phenomena in RBMK-1500 reactor main circulation circuit

    International Nuclear Information System (INIS)

    Kaliatka, A.; Uspuras, E.; Vaisnoras, M.

    2006-01-01

    Water hammer can occur in any thermal-hydraulic systems. Water hammer can reach pressure levels far exceeding the pressure range of a pipe given by the manufacturer, and it can lead to the failure of the pipeline integrity. In the past three decades, since a large number of water hammer events occurred in the light-water- reactor power plants, a number of comprehensive studies on the phenomena associated with water hammer events have been performed. There are three basic types of severe water hammer occurring at power plants that can result in significant plant damage: rapid valve operation events; void-induced water hammer; condensation-induced water hammer. Correct prediction of water hammer transients, is therefore of paramount importance for the safe operation of the plant. Therefore verifying of computer codes capability to simulate water hammer type transients is very important issue at performing of safety analyses for nuclear power plants. Verification of RELAP5/MOD3.3 code capability to simulate water hammer type transients employing the experimental investigations is presented. Experience gained from benchmarking analyses has been used at development of the detail RELAP5 code RBMK-1500 model for simulation of water hammer effects in reactor main circulation circuit. Analysis of reactor cooling system shows, that water hammers can occur in main circulation circuit of RBMK-1500 reactor in cases of: (1) Guillotine break of the inlet piping upstream of the Group Distribution Header and (2) Guillotine break of the pressure piping upstream the Main Circulation Pump check valve. Analysis of above mentioned accident scenarios is presented in this paper. First scenario of the accident potentially is more dangerous, because the pressure pulses influence not only the reactor cooling circuit, but also the piping of safety related system (Emergency Core Cooling System pipeline) connected to affected Group Distribution Header. The performed analysis using RELAP5 code

  2. Water Hammer in Pumped Sewer Mains

    DEFF Research Database (Denmark)

    Larsen, Torben

    This publication is intended for engineers seeking an introduction to the problem of water hammer in pumped pressure mains. This is a subject of increasing interest because of the development of larger and more integrated sewer systems. Consideration of water hammer is essential for structural...

  3. Uncertainty of Water-hammer Loads for Safety Related Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Chan; Yoon, Duk Joo [Korea Hydro and Nuclear Power Co., LT., Daejeon (Korea, Republic of)

    2013-10-15

    In this study, the basic methodology is base on ISO GUM (Guide to the Expression of Uncertainty in Measurements). For a given gas void volumes in the discharge piping, the maximum pressure of water hammer is defined in equation. From equation, uncertainty parameter is selected as U{sub s} (superficial velocity for the specific pipe size and corresponding area) of equation. The main uncertainty parameter (U{sub s}) is estimated by measurement method and Monte Carlo simulation. Two methods are in good agreement with the extended uncertainty. Extended uncertainty of the measurement and Monte Carlo simulation is 1.30 and 1.34 respectively in 95% confidence interval. In 99% confidence interval, the uncertainties are 1.95 and 1.97 respectively. NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the possibility of noncondensable gas accumulation for the Emergency Core Cooling System. Specially, gas accumulation can result in system pressure transient in pump discharge piping at a pump start. Consequently, this evolves into a gas water, a water-hammer event and the force imbalances on the piping segments. In this paper, MCS (Monte Carlo Simulation) method is introduced in estimating the uncertainty of water hammer. The aim is to evaluate the uncertainty of the water hammer estimation results carried out by KHNP CRI in 2013.

  4. Barbara McClintock, Jumping Genes, and Transposition

    Science.gov (United States)

    McClintock Honored * Woman of Science * Educational Material * Resources with Additional Information Barbara McClintock's remarkable life spanned the history of genetics in the twentieth century. ... [T]he science of Dedicate Famous Scientist Stamps ... Woman of Science: McClintock, Barbara and the Jumping Genes, 4,000

  5. Impact Driver With Integral Sliding Hammer

    Science.gov (United States)

    Wallace, Bilby J.

    1987-01-01

    Tool combines impact driver with sliding dead-blow hammer. Used for any purpose for which ordinary impact driver used; tightening fasteners or driving starter holes for drill. Tool protects user from accidental injury and surrounding equipment from damage that might occur from ordinary arm-wielded hammer. Especially useful in underwater work.

  6. Investigation of water hammer in Globochica HPP

    International Nuclear Information System (INIS)

    Bergant, Anton; Saveski, Vasil; Sijamhodjic, Esad

    2004-01-01

    Water hammer should be one of the key elements of the feasibility and design studies in order to ensure safe operation of the hydroelectric power plant (HPP). The main objective of this paper is to identify critical flow regimes which may cause unacceptable water hammer in a Francis turbine HPP. Water hammer is described by the set of hyperbolic partial differential equations, the continuity equation and the equation of motion. The method of characteristics is used for solving these equations. The water turbine is treated as a boundary condition within the method of characteristics. The paper concludes with water hammer analysis in Globocica HPP, Republic of Macedonia. The system tinder consideration is fitted with two 23 MW Francis turbines. There is a reasonable agreement between the computational is field test results. (Author)

  7. Prevention and mitigation of steam generator water hammer events in PWRs

    International Nuclear Information System (INIS)

    Han, J.T.; Anderson, N.

    1983-01-01

    Water hammer in nuclear power plants is an unresolved safety issue under study by the Nuclear Regulatory Commission (NRC). This article summarizes (1) the causes of steam generator water hammer (SGWH) events in pressurized-water reactors (PWRs), (2) various methods used to prevent or mitigate SGWH events, and (3) modifications that have been made at each operating PWR. The NRC staff considers the issue of SGWH in top feedring designs to be technically resolved. This article does not address technical findings relevant to water hammer in preheat-type steam generators

  8. Development of a Piezoelectric Rotary Hammer Drill

    Science.gov (United States)

    Domm, Lukas N.

    2011-01-01

    The Piezoelectric Rotary Hammer Drill is designed to core through rock using a combination of rotation and high frequency hammering powered by a single piezoelectric actuator. It is designed as a low axial preload, low mass, and low power device for sample acquisition on future missions to extraterrestrial bodies. The purpose of this internship is to develop and test a prototype of the Piezoelectric Rotary Hammer Drill in order to verify the use of a horn with helical or angled cuts as a hammering and torque inducing mechanism. Through an iterative design process using models in ANSYS Finite Element software and a Mason's Equivalent Circuit model in MATLAB, a horn design was chosen for fabrication based on the predicted horn tip motion, electromechanical coupling, and neutral plane location. The design was then machined and a test bed assembled. The completed prototype has proven that a single piezoelectric actuator can be used to produce both rotation and hammering in a drill string through the use of a torque inducing horn. Final data results include bit rotation produced versus input power, and best drilling rate achieved with the prototype.

  9. Water hammer and its effect on ageing: an analytical study

    International Nuclear Information System (INIS)

    Kedia, Suruchi

    2006-01-01

    Water hammer can be disastrous from the point of view of ageing of the pipe(s)/Piping system. Design of restraints and protection devices for the various piping systems must consider severe stresses that may generate because of fluid transients. These fluid transients are termed as water hammer when it is restricted to water. But to have limited margins on the stress loads of piping system it is very important to predict the actual dimensions of the stresses. This paper covers various causes and analyses of the situations under which water hammer waves get generated and also way(s) to have control on occurrences of such situations. Few case studies are also covered showing the results and graphs of the stress waves generated because of water hammer. Effort has also been made in the paper in the direction to find out the methodology to compute the ageing of the system because of water hammer waves. Further in this paper an attempt is made to show the systematic methodology towards the diagnosis of water hammer that can be treated as a foundation stone for the creation of water hammer diagnosis system. Active measures to minimize the water hammer intensity by influencing fluid dynamic conditions of the system will also be suggested. Finally the paper will present the ageing aspects because of the stresses that generate due to water hammer. (author)

  10. Simulation of low pressure water hammer

    Science.gov (United States)

    Himr, D.; Habán, V.

    2010-08-01

    Numerical solution of water hammer is presented in this paper. The contribution is focused on water hammer in the area of low pressure, which is completely different than high pressure case. Little volume of air and influence of the pipe are assumed in water, which cause sound speed change due to pressure alterations. Computation is compared with experimental measurement.

  11. OREST, LWR Burnup Simulation Using Program HAMMER and ORIGEN

    International Nuclear Information System (INIS)

    Hesse, Ulrich; Sieberer, Johann

    2006-01-01

    1 - Description of program or function: In OREST, the 1-dimensional lattice code HAMMER and the isotope generation and depletion code ORIGEN are directly coupled for burnup simulation in light-water reactor fuels (GRS recommended). Additionally heavy water and graphite moderated systems can be calculated. New version differs from the previous version in the following features: An 84-group-library LIB84 for up to 200 isotopes is used to update the 3-group -POISON-XS. LIB84 uses the same energy boundaries as THERMOS and HAMLET in . In this way, high flexibility is achieved in very different reactor models. The coupling factor between THERMOS and HAMLET is now directly transferred from HAMMER to THERES and omits the equation 4 (see page 6 of the manual). Sandwich-reactor fuel reactivity and burnup calculations can be started with NGEOM = 1. Thorium graphite reactivity and burnup calculations can be started with NLIBE = 1. High enriched U-235 heavy water moderated reactivity and burnup calculations can be started. HAMLET libraries in for U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-242, Am-241, Am-243 and Zirconium are updated using resonance parameters. NEA-1324/04: A new version of the module hamme97.f has replaced the old one. 2 - Method of solution: For the user-defined irradiation history, an input data processor generates program loops over small burnup steps for the main codes HAMMER and ORIGEN. The user defined assembly description is transformed to an equivalent HAMMER fuel cell. HAMMER solves the integral neutron transport equation in a four-region cylindrical or sandwiched model with reflecting boundaries and runs with fuel power calculated rod temperatures. ORIGEN runs with HAMMER-calculated cross sections and neutron spectra and calculates isotope concentrations during burnup by solving the buildup-, depletion- and decay-chain equations. An output data processor samples the outputs of the program modules and generates tabular works for the

  12. Automated Grid Monitoring for the LHCb Experiment Through HammerCloud

    CERN Document Server

    Dice, Bradley

    2015-01-01

    The HammerCloud system is used by CERN IT to monitor the status of the Worldwide LHC Computing Grid (WLCG). HammerCloud automatically submits jobs to WLCG computing resources, closely replicating the workflow of Grid users (e.g. physicists analyzing data). This allows computation nodes and storage resources to be monitored, software to be tested (somewhat like continuous integration), and new sites to be stress tested with a heavy job load before commissioning. The HammerCloud system has been in use for ATLAS and CMS experiments for about five years. This summer's work involved porting the HammerCloud suite of tools to the LHCb experiment. The HammerCloud software runs functional tests and provides data visualizations. HammerCloud's LHCb variant is written in Python, using the Django web framework and Ganga/DIRAC for job management.

  13. Hammer's Monsters: A Screen Bestiary

    OpenAIRE

    Jones, Matthew; Chibnall, S.

    2016-01-01

    This public exhibition, housed in the DMU Heritage Centre, ran from October 2016 to October 2017. It displayed materials from the Hammer Script Archive held by the Cinema and Television History (CATH) Research Centre at DMU and provided a critical and historical commentary on these materials. Locating the archival objects and images within the industrial and creative history of the iconic Hammer Film Productions, the exhibition invited the public to reflect on the place of this studio within ...

  14. Analysis of water hammer events in nuclear power plants

    International Nuclear Information System (INIS)

    Sato, Masahiro; Yanagi, Chihiro

    1999-01-01

    A water hammer issue in nuclear power plants was one of unresolved safety issues listed by the United States Nuclear Regulatory Commission and was regarded as resolved. But later on, the water hammer events are still experienced intermittently, while the number of the events is decreasing. We collected water hammer events of PWRs in Japan and the United States and relevant documents, analyzed them, and studied corrective actions taken by Japanese plants. As a result, it is confirmed that preventive measured in design, operation etc. have been already taken and that mitigation mechanisms against water hammer have also been considered. However, it is clarified that attention should be continuously paid to operation of valves and/or pumps, as the prevention of water hammer still relies on operation. (author)

  15. Treatise on water hammer in hydropower standards and guidelines

    International Nuclear Information System (INIS)

    Bergant, A; Mazij, J; Karney, B; Pejović, S

    2014-01-01

    This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants

  16. Treatise on water hammer in hydropower standards and guidelines

    Science.gov (United States)

    Bergant, A.; Karney, B.; Pejović, S.; Mazij, J.

    2014-03-01

    This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants.

  17. Metal Forming With a Magnetomotive Hammer

    Science.gov (United States)

    2004-01-01

    During the Apollo era Marshall Space Flight Center's engineers developed the Magnetomotive Hammer to remove distortions from Saturn V bulkhead gore segments. Using an intense magnetic field, the Hammer removed manufacturing distortions from rejected segments which otherwise would have been discarded at a cost of $30,000 each. Various automobile, ship and aircraft manufacturers adoped the technology for commercial use.

  18. Prevention and mitigation of steam-generator water-hammer events in PWR plants

    International Nuclear Information System (INIS)

    Han, J.T.; Anderson, N.

    1982-11-01

    Water hammer in nuclear power plants is an unresolved safety issue under study at the NRC (USI A-1). One of the identified safety concerns is steam generator water hammer (SGWH) in pressurized-water reactor (PWR) plants. This report presents a summary of: (1) the causes of SGWH; (2) various fixes employed to prevent or mitigate SGWH; and (3) the nature and status of modifications that have been made at each operating PWR plant. The NRC staff considers that the issue of SGWH in top feedring designs has been technically resolved. This report does not address technical findings relevant to water hammer in preheat type steam generators. 10 figures, 2 tables

  19. Downhole drilling hammer. Marteau de forage

    Energy Technology Data Exchange (ETDEWEB)

    Techy, M.

    1987-07-28

    This invention concerns a drilling hammer of the downhole type, comprising a tubular body fed by compressed air, a drilling cutter and a hammer piston set into movement inside an interior cylinder by a compressed air distribution mechanism alternately above and below the piston. The hammer includes a gas-oil injection device in the chamber above the piston and a mechanism for initiating the injection during the rising of the piston; the additional compression provokes the combustion of the gas-oil-air mixture, which hurls the piston towards the cutter. This type of apparatus permits an important reduction in costs of materials and of operation, and permits at the same time an increase in drilling power and a reduction in energy consumption. 8 figs.

  20. Design of a water-powered DTH hammer for deep drilling application

    Science.gov (United States)

    Cho, Min Jae; Kim, Donguk; Oh, Joo Young; Yook, Se-Jin; Kim, Young Won

    2017-11-01

    A DTH (Down-the-hole) hammer powered by highly pressurized fluid is a drilling tool using the motion of percussion of a drill bit. In retrospect, a DTH by using compressed air as a power source has been widely used in drilling industries such as applications of mining, geothermal etc. On the other hand, another type of a DTH that uses pressurized water, called a water hammer, has recently seen deep drilling applications, while it has been rarely investigated. In this study, we designed a water-powered DTH hammer which mainly consists of several components such as a piston, a poppet valve, a cap and a bit for deep drilling applications. We optimized the components of the hammer on the basis of the results of 1D analysis using commercial software of AMESIM. An experimental study has been also conducted to investigate a performance of the designed water hammer. We measured a pressure distribution inside the hammer system as a function of time, and it thus estimates a frequency of impaction of the bit, which has been also analyzed in frequency domain. In addition, some important parameters have been discussed in conjunction with a limitation of impaction frequency as input pressure. We believe that this study provides design rules of a water-based DTH for deep drilling applications. This work is supported by KITECH of Korean government.

  1. HammerCloud: A Stress Testing System for Distributed Analysis

    International Nuclear Information System (INIS)

    Ster, Daniel C van der; García, Mario Úbeda; Paladin, Massimo; Elmsheuser, Johannes

    2011-01-01

    Distributed analysis of LHC data is an I/O-intensive activity which places large demands on the internal network, storage, and local disks at remote computing facilities. Commissioning and maintaining a site to provide an efficient distributed analysis service is therefore a challenge which can be aided by tools to help evaluate a variety of infrastructure designs and configurations. HammerCloud is one such tool; it is a stress testing service which is used by central operations teams, regional coordinators, and local site admins to (a) submit arbitrary number of analysis jobs to a number of sites, (b) maintain at a steady-state a predefined number of jobs running at the sites under test, (c) produce web-based reports summarizing the efficiency and performance of the sites under test, and (d) present a web-interface for historical test results to both evaluate progress and compare sites. HammerCloud was built around the distributed analysis framework Ganga, exploiting its API for grid job management. HammerCloud has been employed by the ATLAS experiment for continuous testing of many sites worldwide, and also during large scale computing challenges such as STEP'09 and UAT'09, where the scale of the tests exceeded 10,000 concurrently running and 1,000,000 total jobs over multi-day periods. In addition, HammerCloud is being adopted by the CMS experiment; the plugin structure of HammerCloud allows the execution of CMS jobs using their official tool (CRAB).

  2. Characteristics of laminar MHD fluid hammer in pipe

    International Nuclear Information System (INIS)

    Huang, Z.Y.; Liu, Y.J.

    2016-01-01

    As gradually wide applications of MHD fluid, transportation as well as control with pumps and valves is unavoidable, which induces MHD fluid hammer. The paper attempts to combine MHD effect and fluid hammer effect and to investigate the characteristics of laminar MHD fluid hammer. A non-dimensional fluid hammer model, based on Navier–Stocks equations, coupling with Lorentz force is numerically solved in a reservoir–pipe–valve system with uniform external magnetic field. The MHD effect is represented by the interaction number which associates with the conductivity of the MHD fluid as well as the external magnetic field and can be interpreted as the ratio of Lorentz force to Joukowsky force. The transient numerical results of pressure head, average velocity, wall shear stress, velocity profiles and shear stress profiles are provided. The additional MHD effect hinders fluid motion, weakens wave front and homogenizes velocity profiles, contributing to obvious attenuation of oscillation, strengthened line packing and weakened Richardson annular effect. Studying the characteristics of MHD laminar fluid hammer theoretically supplements the gap of knowledge of rapid-transient MHD flow and technically provides beneficial information for MHD pipeline system designers to better devise MHD systems. - Highlights: • Characteristics of laminar MHD fluid hammer are discussed by simulation. • MHD effect has significant influence on attenuation of wave. • MHD effect strengthens line packing. • MHD effect inhibits Richardson annular effect.

  3. Condensation driven water hammer studies for feed water distribution pipe

    International Nuclear Information System (INIS)

    Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Longvinov, S.A.; Trunov, N.B.; Sitnik, Yu.K.

    1997-01-01

    Special T-shaped feedwater distribution pipes were installed in steam generators at the Loviisa (Finland) and Rovno (Russia) nuclear power plants. The new shape was tested in an extensive testing programme. Since the tubes frequently suffer from corrosion damage, large-scale water hammer experiments were performed on a model facility in 1996. The main objectives of the water hammer experiments were to find out the prevailing parameters leading to water hammers, as well as the sensitivity of hammering to boundary conditions. A water hammer may occur when the mass flow rate into the steam generator exceeds 6 kg/s and the temperature difference between steam generator and feedwater exceeds 100 degC. Visual experiments and stress analyses of the pipe were also carried out. The weakest part, the T-joint, may hold against such water hammers only for a limited time of the order of few minutes. (M.D.)

  4. Optimization analysis of swing check valve closing induced water hammer

    International Nuclear Information System (INIS)

    Han Wenwei; Han Weishi; Guo Qing; Wang Xin; Liu Chunyu

    2014-01-01

    A mathematical-physics model of double pump parallel feed system was constructed. The water hammer was precisely calculated, which was formed in the closing process of swing check valve. And a systematic analysis was carried out to determine the influence of the torques from both valve plate and damping torsion spring on the valve closing induced water hammer. The results show that the swing check valve would distinctly produce the water hammer during the closing procedure in the double pump parallel feed water system. The torques of the valve plate can partly reduce the water hammer effect, and implying appropriate materials of valve plate and appropriate spring can effectively relieve the harm of water hammer. (authors)

  5. Laser fluorosensor overflights of the Santa Barbara oil seeps

    Energy Technology Data Exchange (ETDEWEB)

    Brown, C. E.; Nelson, R. D.; Fingas, M. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div.; Mullin, J. V. [Minerals Management Service, Herndon, VA (United States)

    1997-10-01

    Environment Canada`s Laser Environmental Airborne Fluorosensor (LEAF) system was tested in a series of overflights over naturally occurring oil seeps off Santa Barbara, California. The objective was to test the system`s ability to detect oil in actual marine environments and to distinguish petroleum oil from biogenic oils released by kelp beds in and around these naturally occurring oil seep areas. High resolution colour reconnaissance camera images and down-looking video images were collected concurrently with the fluorescence data for documentation purposes. Results of the experiment were analyzed in detail. They confirmed the system`s ability to produce geo-referenced oil contamination location maps in real-time. The fluorescence data obtained during overflights was most similar to typical crude oil, i. e. the system successfully distinguished between biogenic oil and typical petroleum oil. 9 refs., 1 tab., 3 figs.

  6. Laser fluorosensor overflights of the Santa Barbara oil seeps

    International Nuclear Information System (INIS)

    Brown, C. E.; Nelson, R. D.; Fingas, M.

    1997-01-01

    Environment Canada's Laser Environmental Airborne Fluorosensor (LEAF) system was tested in a series of overflights over naturally occurring oil seeps off Santa Barbara, California. The objective was to test the system's ability to detect oil in actual marine environments and to distinguish petroleum oil from biogenic oils released by kelp beds in and around these naturally occurring oil seep areas. High resolution colour reconnaissance camera images and down-looking video images were collected concurrently with the fluorescence data for documentation purposes. Results of the experiment were analyzed in detail. They confirmed the system's ability to produce geo-referenced oil contamination location maps in real-time. The fluorescence data obtained during overflights was most similar to typical crude oil, i. e. the system successfully distinguished between biogenic oil and typical petroleum oil. 9 refs., 1 tab., 3 figs

  7. WATER HAMMER OSCILLATIONS IN THE IRRIGATION FACILITIES

    Science.gov (United States)

    Kurata, Kouichi; Sasaki, Katsuhito; Makihata, Toshiaki

    In case a gate installed at the end of discharge conduit is vibrating during discharge, or an air valve is vibrating during water-filling operation into the conduit pipe between main gate and auxiliary gate, and vibration period tv is larger than tc (water hammer propagation time) that is equivalent to the phenomenon of slow closure, there is a possibility that water hammer oscillation in the discharge conduit could be induced. In this paper, by using two case examples, vibration phenomena transmitted to each part are analyzed, on the basis of water pressure fluctuation and pressure wave propagation due to occurrence of water hammer oscillation.

  8. Mentors, Muses, and Mutuality: Honoring Barbara Snell Dohrenwend

    Science.gov (United States)

    Mulvey, Anne

    2012-01-01

    I describe feminist community psychology principles that have the potential to expand and enrich mentoring and that honor Barbara Snell Dohrenwend, a leader who contributed to the research, theory, and profession of community psychology. I reflect on the affect that Barbara Dohrenwend had on life and on the development of feminist community…

  9. Pump-stopping water hammer simulation based on RELAP5

    International Nuclear Information System (INIS)

    Yi, W S; Jiang, J; Li, D D; Lan, G; Zhao, Z

    2013-01-01

    RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case

  10. Pump-stopping water hammer simulation based on RELAP5

    Science.gov (United States)

    Yi, W. S.; Jiang, J.; Li, D. D.; Lan, G.; Zhao, Z.

    2013-12-01

    RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case.

  11. Condensation induced water hammer in steam supply system

    International Nuclear Information System (INIS)

    Andrews, P.B.; Antaki, G.A.; Rawls, G.B.; Gutierrez, B.J.

    1995-01-01

    The accidental mixing of steam and water usually leads to condensation induced water hammer. This phenomenon is not uncommon in the power and process industries, and is of particular concern due to the high energies which accompany steam transients. The paper discusses the conditions which lead to a recent condensation induced water hammer in a 150 psig steam supply header. The ensuing structural damage, inspection and repairs are described. Finally, a list of design, maintenance and operational cautions are presented to help minimize the potential for condensation induced water hammer in steam lines

  12. Condensation induced water hammer in steam supply system

    International Nuclear Information System (INIS)

    Andrews, P.B.; Antaki, G.A.; Rawls, G.B.; Gutierrez, B.J.

    1995-01-01

    The accidental mixing of steam and water usually leads to condensation induced water hammer. THis phenomenon is not uncommon in the power and process industries, and is of particular concern due to the high energies which accompany steam transients. The paper discusses the conditions which lead to a recent condensation induced water hammer in a 150 psig steam supply header. The insuing structural damage, inspection and repairs are described. Finally, a list of design cautions are presented to help minimize the potential for condensation induced water hammer in steam lines

  13. Electromagnetic hammer removes weld distortions from aluminum tanks

    Science.gov (United States)

    Schwinghamer, R. J.

    1965-01-01

    Distortions around weld areas on sheet-aluminum tanks and other structures are removed with a portable electromagnetic hammer. The hammer incorporates a coil that generates a controlled high-energy pulsed magnetic field over localized areas on the metal surface.

  14. Vibration and recoil control of pneumatic hammers. [by air flow pressure regulation

    Science.gov (United States)

    Constantinescu, I. N.; Darabont, A. V.

    1974-01-01

    Vibration sources are described for pneumatic hammers used in the mining industry (pick hammers), in boiler shops (riveting hammers), etc., bringing to light the fact that the principal vibration source is the variation in air pressure inside the cylinder. The present state of the art of vibration control of pneumatic hammers as it is practiced abroad, and the solutions adopted for this purpose, are discussed. A new type of pneumatic hammer with a low noise and vibration level is presented.

  15. Preventive measures of water hammer in the design stage of mine drainage system

    International Nuclear Information System (INIS)

    Wu Dongyan

    2012-01-01

    The mechanisms and types of water hammer accident in mine drainage system are introduced. Through calculating water hammer pressure head of pump-failure water hammer, the extent of the harm caused by water hammer can be displayed visually, therefore,the preventive measures to be taken in the design stage are put forward in order to reduce water hammer accident. (author)

  16. Voice Coil Percussive Mechanism Concept for Hammer Drill

    Science.gov (United States)

    Okon, Avi

    2009-01-01

    A hammer drill design of a voice coil linear actuator, spring, linear bearings, and a hammer head was proposed. The voice coil actuator moves the hammer head to produce impact to the end of the drill bit. The spring is used to store energy on the retraction and to capture the rebound energy after each impact for use in the next impact. The maximum actuator stroke is 20 mm with the hammer mass being 200 grams. This unit can create impact energy of 0.4 J with 0.8 J being the maximum. This mechanism is less complex than previous devices meant for the same task, so it has less mass and less volume. Its impact rate and energy are easily tunable without changing major hardware components. The drill can be driven by two half-bridges. Heat is removed from the voice coil via CO2 conduction.

  17. Adaptation of HAMMER computer code to CYBER 170/750 computer

    International Nuclear Information System (INIS)

    Pinheiro, A.M.B.S.; Nair, R.P.K.

    1982-01-01

    The adaptation of HAMMER computer code to CYBER 170/750 computer is presented. The HAMMER code calculates cell parameters by multigroup transport theory and reactor parameters by few group diffusion theory. The auxiliary programs, the carried out modifications and the use of HAMMER system adapted to CYBER 170/750 computer are described. (M.C.K.) [pt

  18. Long-term follow-up of hypothenar hammer syndrome: a series of 47 patients.

    Science.gov (United States)

    Marie, Isabelle; Hervé, Fabien; Primard, Etienne; Cailleux, Nicole; Levesque, Hervé

    2007-11-01

    Hypothenar hammer syndrome (HHS) is an uncommon form of secondary Raynaud phenomenon, occurring mainly in subjects who use the hypothenar part of the hand as a hammer; the hook of the hamate strikes the superficial palmar branch of the ulnar artery in the Guyon space, leading to occlusion and/or aneurysm of the ulnar artery. In patients with HHS, such injuries of the palmar ulnar artery may lead to severe vascular insufficiency in the hand with occlusion of digital artery. To date, only a few series have analyzed the long-term outcome of patients with HHS. This prompted us to conduct the current retrospective study to 1) evaluate the prevalence of HHS in patients with Raynaud phenomenon and 2) assess the short-term and long-term outcome in patients with HHS. From 1990 to 2006, 4148 consecutive patients were referred to the Department of Internal Medicine at the University of Rouen medical center for evaluation of Raynaud phenomenon using nailfold capillaroscopy. HHS was diagnosed in 47 of these 4148 patients (1.13% of cases).Forty-three patients (91.5%) had occupational exposure to repetitive palmar trauma. The more common occupations were factory worker (21.3%), mason (12.8%), carpenter (10.6%), and metal worker (10.6%); the mean duration of occupational exposure to repetitive palmar trauma at HHS diagnosis was 21 years. One patient (2.1%) had recreational exposure (aikido training) to repetitive trauma of the palmar ulnar artery, and 3 other patients (6.4%) developed HHS related to a single direct injury to the hypothenar area. Clinical manifestations were more often unilateral (87.2%) involving the dominant hand (93%). HHS complications included digital ischemic symptoms (ischemia: n = 21, necrosis: n = 20) and irritation of the sensory branch of the ulnar nerve (n = 11). In HHS patients, angiography demonstrated occlusion of the ulnar artery in the area of the Guyon space (59.6%), aneurysm of the ulnar artery in the area of the Guyon space (40.4%), and embolic

  19. Muscle imbalance and reduced ankle joint motion in people with hammer toe deformity.

    Science.gov (United States)

    Kwon, O Y; Tuttle, L J; Johnson, J E; Mueller, M J

    2009-10-01

    Multiple factors may contribute to hammer toe deformity at the metatarsophalangeal joint. The purposes of this study were to (1) compare the ratio of toe extensor/flexor muscle strength in toes 2-4 among groups with and without hammer toe deformity, (2) to determine correlations between the ratio of toe extensor/flexor muscle strength in toes 2-4, and metatarsophalangeal joint deformity (3) to determine if other clinical measures differ between groups and if these measures are correlated with metatarsophalangeal joint angle. Twenty-seven feet with visible hammer toe deformity and 31 age matched feet without hammer toe deformity were tested. Toe muscle strength was measured using a dynamometer and the ratio of toe extensor muscle strength to flexor muscle strength was calculated. Metatarsophalangeal joint angle was measured from a computerized tomography image. Ankle and subtalar joint range of motion, and tibial torsion were measured using goniometry. Extensor/flexor toe muscle strength ratio was 2.3-3.0 times higher in the hammer toe group compared to the non-hammer toe group, in toes 2-4. The ratios of extensor/flexor toe muscle strength for toes 2-4 and metatarsophalangeal joint angle were highly correlated (r=0.69-0.80). Ankle dorsiflexion and metatarsophalangeal joint angle were negatively correlated for toes 2-4 (r=-0.38 to -0.56) as were eversion and metatarsophalangeal joint angle. These results provide insight into potential risk factors for the development of hammer toe deformity. Additional research is needed to determine the causal relationship between hammer toe deformity and the ratio of toe extensor/flexor muscle strength in toes 2-4.

  20. Simulating water hammer with corrective smoothed particle method

    NARCIS (Netherlands)

    Hou, Q.; Kruisbrink, A.C.H.; Tijsseling, A.S.; Keramat, A.

    2012-01-01

    The corrective smoothed particle method (CSPM) is used to simulate water hammer. The spatial derivatives in the water-hammer equations are approximated by a corrective kernel estimate. For the temporal derivatives, the Euler-forward time integration algorithm is employed. The CSPM results are in

  1. Condensation induced water hammer. Overview and own experiments

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan; Doerfler, Michael; Kulisch, Helmut; Malcherek, Andreas

    2012-01-01

    A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this phenomenon and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (orig.)

  2. Condensation-induced water hammer - overview and own experiments

    International Nuclear Information System (INIS)

    Dirndorfer, S.; Doerfler, M.; Kulisch, H.; Malcherek, A.

    2011-01-01

    A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this effect and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (author)

  3. Enhancing down-the-hole air hammer capacity in directional drilling

    Science.gov (United States)

    Klishin, V. I.; Timonin, V. V.; Kokoulin, D. I.; Alekseev, S. E.; Kubanychbek, B.

    2017-09-01

    The authors discuss the issue connected with drilling trajectory deviation and present the technique of rotary-percussion drilling with a down-the-hole air hammer. The article describes pilot testing of the air hammer drill PNB76 in Berezovskaya Mine. The ways of improving the air hammer drill are identified, and the basic diagram and R&D test data are given.

  4. A parametric study of condensation-induced water hammer in nuclear power plants

    International Nuclear Information System (INIS)

    Shon, Young Uk; Chun, Moon Hyun

    1990-01-01

    Condensation-induced water hammer (CIWH), which may occur in systems involving steam and water simultaneously, has a series of processes such as formation of water slug, trapping a steam cavity, depressurization due to steam condensation, accelerating slug caused pressure difference over it and final slug impact. These processes are dependent on water flow rate in a pipe, water temperature, water subcooling, steam pressure, size of slug and cavity, and heat transfer coefficient at interface between steam and water. In the present work, the prediction of conditions to initiate water hammer has been made with full scale by applying the open channel flow theory. These conditions are expressed in terms of water flow rate according to changes of steam pressure, water subcooling, and pipe diameter. Under these conditions that induce CIWH, the effect of parameters which influence on slug impact pressure and cavity collapse rate have been studied with full scale. Also, the impact loads that may be applied to piping design were evaluated under various system conditions

  5. Comparative evaluation of recent water hammer events in light water reactors

    International Nuclear Information System (INIS)

    House, R.K.; Sursock, J.P.; Kim, J.H.

    1987-01-01

    Water hammer events that occurred in commercial U.S. light water reactors in the five-year period from 1981 to 1985 were surveyed, and a preliminary evaluation of the events was conducted. The information developed supplements a previous study which evaluated water hammer events in the twelve-year period from 1969 to 1981. The current study of water hammer events in the 1980's confirms that the rate of events remains relatively constant (less than 0.25 events per plant year) in both PWRs and BWRs. Although water hammer events are not normally considered a safety issue, the economic impact of the events on plant operations can be significant. One particular severe water hammer event is estimated to have cost the plant owner $10 million for repair and evaluation alone. A variety of key characteristics of the recent water hammer events are summarized to establish a basis for further study of preventative methods

  6. La lecture de Merleau-Ponty par Renaud Barbaras

    Czech Academy of Sciences Publication Activity Database

    Pechar, Jiří

    2015-01-01

    Roč. 11, č. 2 (2015), s. 1-6 ISSN 1336-6556 Institutional support: RVO:67985955 Keywords : Merleau-Ponty * Husserl * phenomenology * linguistics of Ferdinand de Saussure Subject RIV: AA - Philosophy ; Religion http://www.ostium.sk/sk/la-lecture-de-merleau-ponty-par-renaud-barbaras/

  7. Pressurized water-reactor feedwater piping response to water hammer

    International Nuclear Information System (INIS)

    Arthur, D.

    1978-03-01

    The nuclear power industry is interested in steam-generator water hammer because it has damaged the piping and components at pressurized water reactors (PWRs). Water hammer arises when rapid steam condensation in the steam-generator feedwater inlet of a PWR causes depressurization, water-slug acceleration, and slug impact at the nearest pipe elbow. The resulting pressure pulse causes the pipe system to shake, sometimes violently. The objective of this study is to evaluate the potential structural effects of steam-generator water hammer on feedwater piping. This was accomplished by finite-element computation of the response of two sections of a typical feedwater pipe system to four representative water-hammer pulses. All four pulses produced high shear and bending stresses in both sections of pipe. Maximum calculated pipe stresses varied because the sections had different characteristics and were sensitive to boundary-condition modeling

  8. Goal Translation for a Hammer for Coq (Extended Abstract

    Directory of Open Access Journals (Sweden)

    Łukasz Czajka

    2016-06-01

    Full Text Available Hammers are tools that provide general purpose automation for formal proof assistants. Despite the gaining popularity of the more advanced versions of type theory, there are no hammers for such systems. We present an extension of the various hammer components to type theory: (i a translation of a significant part of the Coq logic into the format of automated proof systems; (ii a proof reconstruction mechanism based on a Ben-Yelles-type algorithm combined with limited rewriting, congruence closure and a first-order generalization of the left rules of Dyckhoff's system LJT.

  9. Avoiding steam-bubble-collapse-induced water hammers in piping systems

    International Nuclear Information System (INIS)

    Chou, Y.; Griffith, P.

    1989-10-01

    In terms of the frequency of occurrence, steam bubble collapse in subcooled water is the dominant initiating mechanism for water hammer events in nuclear power plants. Water hammer due to steam bubble collapse occurs when water slug forms in stratified horizontal flow, or when steam bubble is trapped at the end of the pipe. These types of water hammer events have been studied experimentally and analytically in order to develop stability maps showing those combinations of filling velocities and liquid subcooling that cause water hammer and those which don't. In developing the stability maps, experiments with different piping orientations were performed in a low pressure laboratory apparatus. Details of these experiments are described, including piping arrangement, test procedures, and test results. Visual tests using a transparent Lexan pipe are also performed to study the flow regimes accompanying the water hammer events. All analytical models were tested by comparison with the corresponding experimental results. Based on these models, and step-by-step approach for each flow geometry is presented for plant designers and engineers to follow in avoiding water hammer induced by steam bubble collapse when admitting cold water into pipes filled with steam. 37 refs., 54 figs., 2 tabs

  10. Water hammer characteristics of integral pressurized water reactor primary loop

    International Nuclear Information System (INIS)

    Zuo, Qiaolin; Qiu, Suizheng; Lu, Wei; Tian, Wenxi; Su, Guanghui; Xiao, Zejun

    2013-01-01

    Highlights: • Water hammer models developed for IPWR primary loop using MOC. • Good agreement between the developed code and the experiment. • The good agreement between WAHAP and Flowmaster can validate the equations in WAHAP. • The primary loop of IPWR suffers from slight water hammer impact. -- Abstract: The present work discussed the single-phase water hammer phenomenon, which was caused by the four-pump-alternate startup in an integral pressurized water reactor (IPWR). A new code named water hammer program (WAHAP) was developed independently based on the method of characteristic to simulate hydraulic transients in the primary system of IPWR and its components such as reactor core, once-through steam generators (OTSG), the main coolant pumps and so on. Experimental validation for the correctness of the equations and models in WAHAP was carried out and the models fit the experimental data well. Some important variables were monitored including transient volume flow rates, opening angle of valve disc and pressure drop in valves. The water hammer commercial software Flowmaster V7 was also employed to compare with WAHAP and the good agreement can validate the equations in WAHAP. The transient results indicated that the primary loop of IPWR suffers from slight water hammer impact under pump switching conditions

  11. Water hammer characteristics of integral pressurized water reactor primary loop

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Qiaolin [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Qiu, Suizheng, E-mail: szqiu@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Lu, Wei; Tian, Wenxi; Su, Guanghui [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Xiao, Zejun [Nuclear Power Institute of China, Chengdu, Sichuan 610041 (China)

    2013-08-15

    Highlights: • Water hammer models developed for IPWR primary loop using MOC. • Good agreement between the developed code and the experiment. • The good agreement between WAHAP and Flowmaster can validate the equations in WAHAP. • The primary loop of IPWR suffers from slight water hammer impact. -- Abstract: The present work discussed the single-phase water hammer phenomenon, which was caused by the four-pump-alternate startup in an integral pressurized water reactor (IPWR). A new code named water hammer program (WAHAP) was developed independently based on the method of characteristic to simulate hydraulic transients in the primary system of IPWR and its components such as reactor core, once-through steam generators (OTSG), the main coolant pumps and so on. Experimental validation for the correctness of the equations and models in WAHAP was carried out and the models fit the experimental data well. Some important variables were monitored including transient volume flow rates, opening angle of valve disc and pressure drop in valves. The water hammer commercial software Flowmaster V7 was also employed to compare with WAHAP and the good agreement can validate the equations in WAHAP. The transient results indicated that the primary loop of IPWR suffers from slight water hammer impact under pump switching conditions.

  12. A wireless sensor system for a biofeedback training of hammer throwers.

    Science.gov (United States)

    Wang, Ye; Wan, Bingjun; Li, Hua; Shan, Gongbing

    2016-01-01

    Hammer-throw has a long-standing history in track and field, but unlike some other sports events, men's hammer throw has not seen a new world record since 1986. One of the possible reasons for this stagnation could be the lack of real-time biomechanical feedback training. In this study, we proposed to establish scientifically described training targets and routes, which in turn required tools that could measure and quantify characteristics of an effective hammer-throw. Towards this goal, we have developed a real-time biomechanical feedback device-a wireless sensor system-to help the training of hammer-throw. The system includes two sensors-an infrared proximity sensor for tracing the hip vertical movement and a load cell for recording the wire tension during a hammer-throw. The system uses XBees for data transmission and an Arduino processor for data processing and system control. The results revealed that the wire tension measurement could supply sufficient key features for coaches to analyze hammer-throw and give real-time feedback for improving training efficiency.

  13. The Velvet Hammer

    Science.gov (United States)

    Henderson, Nancy

    2008-01-01

    This article features the life of Louise Underwood, an advocate for people with disabilities and their families. Underwood is known for her nickname "The Velvet Hammer" because of her relentless attitude when it comes to advocating for people with disabilities. Many times she has pulled strings to halt legislation that would have…

  14. Analytical models for lower and upper bounds of the condensation-induced water hammer in long horizontal pipes

    International Nuclear Information System (INIS)

    Chun, Moon Hyun; Park, Joo Wan; Nam, Ho Yun

    1992-01-01

    Improved analytical models have been proposed that can predict the lower and upper limits of the water hammer region for given flow conditions by incorporation of recent advances made in the understanding of phenomena associated with the condensation-induced water hammer into existing methods. Present models are applicable for steam-water counterflow in a long horizontal pipe geometry. Both lower and upper bounds of the water hammer region are expressed in terms of the 'critical inlet water flow rate' as a function of axial position. Water hammer region boundaries predicted by present and typical existing models are compared for particular flow conditions of the water hammer event occurred at San Onofre Unit 1 to assess the applicability of the models examined. The result shows that present models for lower and upper bounds of the water hammer region compare favorably with the best performing existing models

  15. Overview of Prevention for Water Hammer by Check Valve Action in Nuclear Reactor

    International Nuclear Information System (INIS)

    Kim, Dayong; Yoon, Hyungi; Seo, Kyoungwoo; Kim, Seonhoon

    2016-01-01

    Water hammer can cause serious damage to pumping system and unexpected system pressure rise in the pipeline. In nuclear reactor, water hammer can influence on the integrity of safety related system. Water hammer in nuclear reactor have been caused by voiding in normally water-filled lines, steam condensation line containing both steam and water, as well as by rapid check valve action. Therefore, this study focuses on the water hammer by check valve among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. This study focuses on the water hammer by check valve action among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. If the inadvertent pump trip or pipe rupture in high velocity and pressure pipe is predicted, the fast response check valve such as tiled disc, dual disc and nozzle check valve should be installed in the system. If the inadvertent pump trip or pipe rupture in very high velocity and pressure pipe and excessively large revered flow velocity are predicted, the very slowly closing check valve such as controlled closure check valve should be installed in the system

  16. Overview of Prevention for Water Hammer by Check Valve Action in Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dayong; Yoon, Hyungi; Seo, Kyoungwoo; Kim, Seonhoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Water hammer can cause serious damage to pumping system and unexpected system pressure rise in the pipeline. In nuclear reactor, water hammer can influence on the integrity of safety related system. Water hammer in nuclear reactor have been caused by voiding in normally water-filled lines, steam condensation line containing both steam and water, as well as by rapid check valve action. Therefore, this study focuses on the water hammer by check valve among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. This study focuses on the water hammer by check valve action among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. If the inadvertent pump trip or pipe rupture in high velocity and pressure pipe is predicted, the fast response check valve such as tiled disc, dual disc and nozzle check valve should be installed in the system. If the inadvertent pump trip or pipe rupture in very high velocity and pressure pipe and excessively large revered flow velocity are predicted, the very slowly closing check valve such as controlled closure check valve should be installed in the system.

  17. Compilation of data concerning know and suspected water hammer events in nuclear power plants, CY 1969

    International Nuclear Information System (INIS)

    Chapman, R.L.; Christensen, D.D.; Dafoe, R.E.; Hanner, O.M.; Wells, M.E.

    1981-05-01

    This report compiles data concerning known and suspected water hammer events reported by BWR and PWR power plants in the United States from January 1, 1969, to May 1, 1981. This information is summarized for each event and is tabulated for all events by plant, plant type, year of occurrence, type of water hammer, system affected, basis/cause for the event, and damage incurred. Information is also included from other events not specifically identified as water hammer related. These other events involved vibration and/or system components similar to those involved in the water hammer events. The other events are included to ensure completeness of the report, but are not used to point out particular facts or trends. This report does not evaluate findings abstracted from the data

  18. Analysis and prevention of water hammer for the emergency core cooling system

    International Nuclear Information System (INIS)

    Zhao Jun

    2008-01-01

    Emergency core cooling system (ECCS) is an engineered safety feature of nuclear power plant. If the water hammer happens during ECCS injection, the piping system may be broken. It will cause loss of ECC system and affect the safety of reactor core. Based on the functions and characteristics of ECCS and the theory of water hammer, the paper analyzed the potential risk of water hammer in ECCS in Qinshan III, and proposed modifications to prevent the water-hammer damage during ECCS injection. (authors)

  19. Water hammer conservatisms

    International Nuclear Information System (INIS)

    Uffer, R.A.

    1993-01-01

    Calculated water hammer forces often contain excessive conservatisms resulting in unrealistic damage predictions. This is especially true for void filling and column separation scenarios. Pressure rise times can be as important as pressure amplitudes. Forces based on in situ test data can also contain excessive conservatisms. This paper discusses the causes of such conservatisms and means of minimizing them

  20. 2016-2017 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Beata Bialic

    2016-11-28 to 2016-11-30. Destination(s):. Ottawa. Airfare: $1,078.05. Other. Transportation: $135.00. Accommodation: $194.37. Meals and. Incidentals: $216.80. Other: $0.00. Total: $1,624.22. Comments: 2016-2017 Travel Expense Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit ...

  1. Hammering Does Not Fit Fitts' Law

    Directory of Open Access Journals (Sweden)

    Tadej Petrič

    2017-05-01

    Full Text Available While movement is essential to human wellbeing, we are still unable to reproduce the deftness and robustness of human movement in automatons or completely restore function to individuals with many types of motor impairment. To better understand how the human nervous system plans and controls movements, neuromechanists employ simple tasks such as upper extremity reaches and isometric force tasks. However, these simple tasks rarely consider impacts and may not capture aspects of motor control that arise from real-world complexity. Here we compared existing models of motor control with the results of a periodic targeted impact task extended from Bernstein's seminal work: hammering a nail into wood. We recorded impact forces and kinematics from 10 subjects hammering at different frequencies and with hammers with different physical properties (mass and face area. We found few statistical differences in most measures between different types of hammer, demonstrating human robustness to minor changes in dynamics. Because human motor control is thought to obey optimality principles, we also developed a feedforward optimal simulation with a neuromechanically inspired cost function that reproduces the experimental data. However, Fitts' Law, which relates movement time to distance traveled and target size, did not match our experimental data. We therefore propose a new model in which the distance moved is a logarithmic function of the time to move that yields better results (R2 ≥ 0.99 compared to R2 ≥ 0.88. These results support the argument that humans control movement in an optimal way, but suggest that Fitts' Law may not generalize to periodic impact tasks.

  2. A Comparative Analysis of the Rebound Hammer and Ultrasonic ...

    African Journals Online (AJOL)

    This work presents a study on the comparison between some non-destructive testing tech-niques (Rebound Hammer and Ultrasonic Pulse Velocity). Tests were performed to com-pare the accuracy between the rebound hammer and the ultrasonic pulse velocity methodin estimating the strength of concrete. Eighty samples ...

  3. Volpentest HAMMER Federal Training Center

    Data.gov (United States)

    Federal Laboratory Consortium — HAMMER stands for Hazardous Materials Management and Emergency Response, and was named for Sam Volpentest, a long-time community leader and advocate of the Hanford...

  4. INTEGRATED DRILLING SYSTEM USING MUD ACTUATED DOWN HOLE HAMMER AS PRIMARY ENGINE

    Energy Technology Data Exchange (ETDEWEB)

    John V. Fernandez; David S. Pixton

    2005-12-01

    A history and project summary of the development of an integrated drilling system using a mud-actuated down-hole hammer as its primary engine are given. The summary includes laboratory test results, including atmospheric tests of component parts and simulated borehole tests of the hammer system. Several remaining technical hurdles are enumerated. A brief explanation of commercialization potential is included. The primary conclusion for this work is that a mud actuated hammer can yield substantial improvements to drilling rate in overbalanced, hard rock formations. A secondary conclusion is that the down-hole mud actuated hammer can serve to provide other useful down-hole functions including generation of high pressure mud jets, generation of seismic and sonic signals, and generation of diagnostic information based on hammer velocity profiles.

  5. Unusual Cases of Hypothenar Hammer Syndrome.

    Science.gov (United States)

    Orrapin, Saranat; Arworn, Supapong; Wisetborisut, Anawat

    2015-01-01

    Hypothenar hammer syndrome (HHS) is a rare occupational disease. The risk group of HHS is patient whose dominate hand used as a hammer. Our study report unusually cases in Chiang Mai University Hospital. 19 year-old basketball player had right ulnar artery aneurysm for two months. After operation, his symptom was relieved and returned to play basketball again. 65 year-old housekeeper had non-dominated hand ulnar artery aneurysm for two years. After operation she still had hand claudication due to poor run-off vessel. HHS is previously state in risk group. But from our report there was a risk in different occupation.

  6. Do chimpanzees use weight to select hammer tools?

    Directory of Open Access Journals (Sweden)

    Cornelia Schrauf

    Full Text Available The extent to which tool-using animals take into account relevant task parameters is poorly understood. Nut cracking is one of the most complex forms of tool use, the choice of an adequate hammer being a critical aspect in success. Several properties make a hammer suitable for nut cracking, with weight being a key factor in determining the impact of a strike; in general, the greater the weight the fewer strikes required. This study experimentally investigated whether chimpanzees are able to encode the relevance of weight as a property of hammers to crack open nuts. By presenting chimpanzees with three hammers that differed solely in weight, we assessed their ability to relate the weight of the different tools with their effectiveness and thus select the most effective one(s. Our results show that chimpanzees use weight alone in selecting tools to crack open nuts and that experience clearly affects the subjects' attentiveness to the tool properties that are relevant for the task at hand. Chimpanzees can encode the requirements that a nut-cracking tool should meet (in terms of weight to be effective.

  7. Condensate induced water hammer in a steam distribution system results in fatality

    International Nuclear Information System (INIS)

    Debban, H.L.; Eyre, L.E.

    1996-02-01

    Water hammer event s in steam distribution piping interrupt service and have the potential to cause serious injury and property damage. Conditions of condensation induced water hammer are discussed and recommendations aimed to improve safety of steam systems are presented. Condensate induced water hammer events at Hanford, a DOE facility, are examined

  8. Assessment of Analytic Water hammer Pressure Model of FAI/08-70

    International Nuclear Information System (INIS)

    Park, Ju Yeop; Yoo, Seung Hun; Seul, Kwang-Won

    2016-01-01

    In evaluating water hammer effect on the safety related systems, methods developed by the US utility are likely to be adopted in Korea. For example, the US utility developed specific methods to evaluate pressure and loading transient on piping due to water hammer as in FAI/08-70. The methods of FAI/08-70 would be applied in Korea when any regulatory request on the evaluation of water hammer effect due to the non-condensable gas accumulation in the safety related systems. Specifically, FAI/08-70 gives an analytic model which can be used to analyze the maximum transient pressure and maximum transient loading on the piping of the safety-related systems due to the non-condensable induced water hammer effect. Therefore, it seems to be meaningful to review the FAI/08-70 methods and attempt to apply the methods to a specific case to see if they really give reasonable estimate before the application of FAI/08-70 methods to domestic nuclear power plants. In the present study, analytic water hammer pressure model of FAI/08-70 is reviewed in detail and the model is applied to the specific experiment of FAI/08-70 to see if the analytic water hammer pressure model really gives reasonable estimate of the peak water hammer pressure. Specifically, we assess the experiment 52A of FAI/08-70 which adopts flushed initial condition with a short rising piping length and a high level piping length of 51inch. The calculated analytic water hammer pressure peak shows a close agreement with the measured experimental data of 52A. Unfortunately, however, the theoretical value is a little bit less than that of the experimental value. This implies the analytic model of FAI/08-70 is not conservative

  9. Assessment of Analytic Water hammer Pressure Model of FAI/08-70

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ju Yeop; Yoo, Seung Hun; Seul, Kwang-Won [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    In evaluating water hammer effect on the safety related systems, methods developed by the US utility are likely to be adopted in Korea. For example, the US utility developed specific methods to evaluate pressure and loading transient on piping due to water hammer as in FAI/08-70. The methods of FAI/08-70 would be applied in Korea when any regulatory request on the evaluation of water hammer effect due to the non-condensable gas accumulation in the safety related systems. Specifically, FAI/08-70 gives an analytic model which can be used to analyze the maximum transient pressure and maximum transient loading on the piping of the safety-related systems due to the non-condensable induced water hammer effect. Therefore, it seems to be meaningful to review the FAI/08-70 methods and attempt to apply the methods to a specific case to see if they really give reasonable estimate before the application of FAI/08-70 methods to domestic nuclear power plants. In the present study, analytic water hammer pressure model of FAI/08-70 is reviewed in detail and the model is applied to the specific experiment of FAI/08-70 to see if the analytic water hammer pressure model really gives reasonable estimate of the peak water hammer pressure. Specifically, we assess the experiment 52A of FAI/08-70 which adopts flushed initial condition with a short rising piping length and a high level piping length of 51inch. The calculated analytic water hammer pressure peak shows a close agreement with the measured experimental data of 52A. Unfortunately, however, the theoretical value is a little bit less than that of the experimental value. This implies the analytic model of FAI/08-70 is not conservative.

  10. Systematic methodology for diagnosis of water hammer in LWR power plants

    International Nuclear Information System (INIS)

    Safwat, H.H.; Arastu, A.H.; Husaini, S.M.

    1990-01-01

    The paper gives the dimensions of the knowledge base that is necessary to carry out a diagnosis of water hammer susceptibility/root cause analyses for Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) nuclear power plant systems. After introducing some fundamentals, water hammer phenomena are described. Situations where each phenomenon is encountered are given and analytical models capable of simulating the phenomena are referenced. Water hammer events in operating plants and their inclusion in the knowledge base is discussed. The diagnostic methodology is presented through an application on a system in a typical light water reactor plant. The methodology presented serves as a possible foundation for the creation of an expert water hammer diagnosis system. (orig.)

  11. Condensation induced water hammer safety

    International Nuclear Information System (INIS)

    Gintner, M.A.

    1997-01-01

    Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer

  12. Influence of fluiddynamic parameters upon fluid-hammer forces and spectra

    International Nuclear Information System (INIS)

    Meder, G.; Grams, J.

    1984-01-01

    For proper dynamic calculation of piping systems under fluid-hammer loading it is necessary to know the frequency content of the fluid-hammer force. Therefore, in this paper, the spectra of fluid-hammer loading will be examined. In particular, the influence of a change of fluiddynamic parameters upon the spectra will be investigated. When changes are made, the normal result is a change or shift in the frequency content of the spectra. However, for changes in certain fluiddynamic parameters, only the force amplitudes are changed. Both types of changes will be discussed. (orig.)

  13. 2016-2017 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Beata Bialic

    Destination(s):. Peru/Colombia. Airfare: $3,662.66. Other. Transportation: $40.00. Accommodation: $1,941.64. Meals and. Incidentals: $608.10. Other: $93.22. Total: $6,345.62. Comments: 2016-2017 Travel Expense Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit Committee.

  14. 2017-2018 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Airfare: $436.15. Other. Transportation: $98.00. Accommodation: $361.85. Meals and. Incidentals: $219.51. Other: $0.00. Total: $1,115.51. Comments: From her residence in Fredericton, NB. 2017-2018 Travel Expense Reports for. Barbara Lucille Trenholm, Governor,. Chairperson of the Finance and Audit. Committee.

  15. Santa Barbara Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, Angela; Hansen, Sherman; Watkins, Ashley

    2013-11-30

    This report serves as the Final Report for Santa Barbara County’s Energy Efficiency and Conservation Block Grant (EECBG) BetterBuildings Neighborhood Program (BBNP) award from the U.S. Department of Energy (DOE). This report explains how DOE BBNP funding was invested to develop robust program infrastructure designed to help property owners complete energy improvements, thereby generating substantial outcomes for the local environment and economy. It provides an overview of program development and design within the grant period, program accomplishments and challenges to date, and a plan for the future sustainability of emPower, the County’s innovative clean energy and building efficiency program. During the grant period, Santa Barbara County’s emPower program primarily targeted 32,000 owner occupied, single family, detached residential homes over 25 years old within the County. In order to help these homeowners and their contractors overcome market barriers to completing residential energy improvements, the program developed and promoted six voluntary, market-based service areas: 1) low cost residential financing (loan loss reserve with two local credit unions), 2) residential rebates, 3) local customer service, 4) expert energy advising, 5) workforce development and training, and 6) marketing, education and outreach. The main goals of the program were to lower building energy use, create jobs and develop a lasting regional building performance market. These services have generated important early outcomes and lessons after the program’s first two years in service. The DOE BBNP funding was extended through October 2014 to enable Santa Barbara County to generate continued outcomes. In fact, funding related to residential financing remains wholly available for the foreseeable future to continue offering Home Upgrade Loans to approximately 1,300 homeowners. The County’s investment of DOE BBNP funding was used to build a lasting, effective, and innovative

  16. Load and wear experiments on the impact hammer of a vertical shaft impact crusher

    International Nuclear Information System (INIS)

    Yang, J H; Fang, H Y; Luo, M

    2015-01-01

    Impact hammers are important components of impact crushers, and are often shortlived due to the high-impact nature of their use. Wear-resistant alloys are welded to the surface of impact hammers to prolong their service life. In this paper, a simulation model of the rotor and impact hammers in impact crushers was designed to utilize the Discrete Element Method (DEM). The wear-resistant alloy on each impact hammer was divided into twenty-two action regions. The load distribution on each alloy block is affected by the structural and manufacturing parameters of the impact crusher. The wear distribution of the impact hammer was measured by shape morphology according to relative impact crushers. The results demonstrated that the real measurements of wear distribution on the impact hammer were similar to simulated load distribution measurements on the same surface. The study of load distribution of impact hammers by DEM established a theoretical foundation on which to base the optimal design of impact crushers. (paper)

  17. Chebyshev super spectral viscosity method for water hammer analysis

    Directory of Open Access Journals (Sweden)

    Hongyu Chen

    2013-09-01

    Full Text Available In this paper, a new fast and efficient algorithm, Chebyshev super spectral viscosity (SSV method, is introduced to solve the water hammer equations. Compared with standard spectral method, the method's advantage essentially consists in adding a super spectral viscosity to the equations for the high wave numbers of the numerical solution. It can stabilize the numerical oscillation (Gibbs phenomenon and improve the computational efficiency while discontinuities appear in the solution. Results obtained from the Chebyshev super spectral viscosity method exhibit greater consistency with conventional water hammer calculations. It shows that this new numerical method offers an alternative way to investigate the behavior of the water hammer in propellant pipelines.

  18. Grid site testing for ATLAS with HammerCloud

    International Nuclear Information System (INIS)

    Elmsheuser, J; Hönig, F; Legger, F; LLamas, R Medrano; Sciacca, F G; Ster, D van der

    2014-01-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling virtual organisations (VO) and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test workflows. These new workflows comprise e.g. tests of the ATLAS nightly build system, ATLAS Monte Carlo production system, XRootD federation (FAX) and new site stress test workflows. We report on the development, optimization and results of the various components in the HammerCloud framework.

  19. Grid Site Testing for ATLAS with HammerCloud

    CERN Document Server

    Elmsheuser, J; The ATLAS collaboration; Legger, F; Medrano LLamas, R; Sciacca, G; van der Ster, D

    2014-01-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test work-flows. These new work-flows comprise e.g. tests of the ATLAS nightly build system, ATLAS MC production system, XRootD federation FAX and new site stress test work-flows. We report on the development, optimization and results of the various components in the HammerCloud framework.

  20. Grid Site Testing for ATLAS with HammerCloud

    CERN Document Server

    Elmsheuser, J; The ATLAS collaboration; Legger, F; Medrano LLamas, R; Sciacca, G; van der Ster, D

    2013-01-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test work-flows. These new work-flows comprise e.g. tests of the ATLAS nightly build system, ATLAS MC production system, XRootD federation FAX and new site stress test work-flows. We report on the development, optimization and results of the various components in the HammerCloud framework.

  1. Proximal forearm extensor muscle strain is reduced when driving nails using a shock-controlled hammer.

    Science.gov (United States)

    Buchanan, Kimberly A; Maza, Maria; Pérez-Vázquez, Carlos E; Yen, Thomas Y; Kijowski, Richard; Liu, Fang; Radwin, Robert G

    2016-10-01

    Repetitive hammer use has been associated with strain and musculoskeletal injuries. This study investigated if using a shock-control hammer reduces forearm muscle strain by observing adverse physiological responses (i.e. inflammation and localized edema) after use. Three matched framing hammers were studied, including a wood-handle, steel-handle, and shock-control hammer. Fifty volunteers were randomly assigned to use one of these hammers at a fatiguing pace of one strike every second, to seat 20 nails in a wood beam. Magnetic resonance imaging was used to scan the forearm muscles for inflammation before the task, immediately after hammering, and one to two days after. Electromyogram signals were measured to estimate grip exertions and localized muscle fatigue. High-speed video was used to calculate the energy of nail strikes. While estimated grip force was similar across the three hammers, the shock-control hammer had 40% greater kinetic energy upon impact and markedly less proximal extensor muscle edema than the wood-handle and steel-handle hammers, immediately after use (phandle shock can mitigate strain in proximal forearm extensor muscles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A Hammer-Impact, Aluminum, Shear-Wave Seismic Source

    Science.gov (United States)

    Haines, Seth

    2007-01-01

    Near-surface seismic surveys often employ hammer impacts to create seismic energy. Shear-wave surveys using horizontally polarized waves require horizontal hammer impacts against a rigid object (the source) that is coupled to the ground surface. I have designed, built, and tested a source made out of aluminum and equipped with spikes to improve coupling. The source is effective in a variety of settings, and it is relatively simple and inexpensive to build.

  3. Modelling water hammer in viscoelastic pipelines: short brief

    Science.gov (United States)

    Urbanowicz, K.; Firkowski, M.; Zarzycki, Z.

    2016-10-01

    The model of water hammer in viscoelastic pipelines is analyzed. An appropriate mathematical model of water hammer in polymer pipelines is presented. An additional term has been added to continuity equation to describe the retarded deformation of the pipe wall. The mechanical behavior of viscoelastic material is described by generalized Kelvin-Voigt model. The comparison of numerical simulation and experimental data from well known papers is presented. Short discussion about obtained results are given.

  4. 2016-2017 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Beata Bialic

    2016-06-20 to 2016-06-22. Destination(s):. Ottawa. Airfare: $603.34. Other. Transportation: $147.00. Accommodation: $393.40. Meals and. Incidentals: $154.83. Other: $0.00. Total: $1,298.57. Comments: 2016-2017 Travel Expense Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit ...

  5. 2016-2017 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Beata Bialic

    2016-11-20 to 2016-11-23. Destination(s):. Ottawa. Airfare: $572.30. Other. Transportation: $130.00. Accommodation: $590.10. Meals and. Incidentals: $310.40. Other: $0.00. Total: $1,602.80. Comments: 2016-2017 Travel Expense Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit ...

  6. 2016-2017 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    chantal taylor

    Finance and Audit Committee meeting. Date(s):. 2017-02-07 to 2017-02-09. Destination(s):. Ottawa. Airfare: $492.53. Other. Transportation: $70.00. Accommodation: $696.25. Meals and. Incidentals: $69.60. Other: $0.00. Total: $1,328.38. Comments: 2016-2017 Travel Expense Reports for Barbara. Lucille Trenholm ...

  7. Condensation induced water hammer safety

    Energy Technology Data Exchange (ETDEWEB)

    Gintner, M.A.

    1997-03-10

    Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer.

  8. Improving ATLAS computing resource utilization with HammerCloud

    CERN Document Server

    Schovancova, Jaroslava; The ATLAS collaboration

    2018-01-01

    HammerCloud is a framework to commission, test, and benchmark ATLAS computing resources and components of various distributed systems with realistic full-chain experiment workflows. HammerCloud contributes to ATLAS Distributed Computing (ADC) Operations and automation efforts, providing the automated resource exclusion and recovery tools, that help re-focus operational manpower to areas which have yet to be automated, and improve utilization of available computing resources. We present recent evolution of the auto-exclusion/recovery tools: faster inclusion of new resources in testing machinery, machine learning algorithms for anomaly detection, categorized resources as master vs. slave for the purpose of blacklisting, and a tool for auto-exclusion/recovery of resources triggered by Event Service job failures that is being extended to other workflows besides the Event Service. We describe how HammerCloud helped commissioning various concepts and components of distributed systems: simplified configuration of qu...

  9. Interview: William and Barbara Christopher.

    Science.gov (United States)

    Teaching Exceptional Children, 1986

    1986-01-01

    Asserting that the biggest mistake educators can make is to set themselves up as experts vis-a-vis parents as amateurs, Barbara and William Christopher emphasize the importance of continued education for the autistic individual and relate their experiences with the educational community as they sought help for their autistic son. (JC)

  10. On the Wave Stresses in the Rods of Anvil Hammers

    Directory of Open Access Journals (Sweden)

    V. M. Sinitskiy

    2014-01-01

    Full Text Available With operating anvil hammers, there are rigid impacts of die tools, and as a result, almost instantaneous impact stops of the falling parts of hammer. Such operating conditions lead to the accelerated breakdowns of rods because of significant wave stresses arising in them. Common differential and integral methods to estimate wave stresses are widespread in engineering practice. However, to use them a researcher has to possess certain skills and special software. We consider the method for estimating the wave stresses in the rods of anvil hammers based on Laplace transforms (LT of wave equation. The article shows a procedure to set up and solve differential wave equations by operator method. These equations describe the wave propagation process of strains and stresses in the rods of anvil hammers with rigid impact and taking into account a damping rod connection with the head of hammer. The method takes into consideration an influence of both piston and rod weights and of mechanical and geometrical characteristics of rod on the stress value in the placement of rod in hammer head. Results analysis shows that a sufficiently efficient method for practical improving the durability of rods is the method of damping impact load on the rod through setting the damping devices in the form either of elastic "pad" of one or another design or of hydraulic shock absorbers in the placement of its connection with the hammer head. In this case there is a change of the wave front, it becomes flatter. It is shown that the stresses in the rod are proportional to the amount of wave stresses because of the own impact of rod and piston, which make a total weight of the system. Effect of piston weight on the stresses value at the rod during impact is directly proportional to the ratio of its weight to the rod weight. The geometric parameters of rod and the speed of the falling parts before the impact also influence on the value of stresses in the rod.The represented

  11. Water hammer (with FSI): exact solution : parallelization and application

    NARCIS (Netherlands)

    Loh, K.; Tijsseling, A.S.

    2014-01-01

    The 1D fully coupled Fluid-Structure Interaction (FSI) model can adequately describe the water hammer effect on the fluid, and the structural behaviour of the pipe. This paper attempts to increase the capability of using an exact solution of the 1D FSI problem applied to a straight pipe with a

  12. Hypothenar hammer syndrome in an office worker.

    Science.gov (United States)

    Zhang, Fan; Weerakkody, Yuranga; Tosenovsky, Patrik

    2017-12-01

    Hypothenar hammer syndrome (HHS) is an uncommon cause of unilateral Raynaud's phenomenon, splinter haemorrhages and hypothenar weakness. The typical patient is a male blue-collar worker who uses their hypothenar eminence to hammer objects as part of their work. The distal ulnar artery beyond Guyon's canal is superficial and vulnerable to blunt trauma. CTA and MRA are common initial investigations and can suggest the diagnosis. DSA is the gold standard imaging modality and offers therapeutic opportunities. Management is controversial, but unless there is critical digital ischaemia, conservative treatment is first line. © 2017 The Royal Australian and New Zealand College of Radiologists.

  13. Condensation driven water hammer studies for feedwater distribution pipe

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J. [Imatran Voima Oy, Vantaa (Finland); Pullinen, J. [IVO Power Engineering Ltd., Vantaa (Finland); Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K. [EDO Gidropress (Russian Federation)

    1997-12-31

    Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.).

  14. Condensation driven water hammer studies for feedwater distribution pipe

    International Nuclear Information System (INIS)

    Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J.; Pullinen, J.; Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K.

    1997-01-01

    Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.)

  15. Condensation driven water hammer studies for feedwater distribution pipe

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, S; Katajala, S; Elsing, B; Nurkkala, P; Hoikkanen, J [Imatran Voima Oy, Vantaa (Finland); Pullinen, J [IVO Power Engineering Ltd., Vantaa (Finland); Logvinov, S A; Trunov, N B; Sitnik, J K [EDO Gidropress (Russian Federation)

    1998-12-31

    Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.).

  16. Specific Characteristics of Injuries Inflicted by Claw Hammer.

    Science.gov (United States)

    Buchaillet, Céline; Gaudin, Arnaud; Rougé-Maillart, Clotilde; Jousset, Nathalie

    2016-09-01

    Claw hammers have the specific characteristic of having two distinct ends: one a flat head of variable form, the other bifurcated. So the use of this tool as a blunt instrument will cause varying injuries. The authors present two clinical cases of assault with a claw hammer. Examinations revealed two types of wound. A first injury composed of integumentary lacerations and underlying bone injuries in terms of "shape" suggested the use of a blunt instrument. A second injury made up of damage showing two parallel wounds or two wounds located one in the extension of the other suggested the use of an object with a bifurcated end. The combination of both types of injury should alert examiners to the possibility of the use of a claw hammer in causing the injuries in order to help direct investigators in their investigations and in the search for the weapon used. © 2016 American Academy of Forensic Sciences.

  17. Effects of air vessel on water hammer in high-head pumping station

    International Nuclear Information System (INIS)

    Wang, L; Wang, F J; Zou, Z C; Li, X N; Zhang, J C

    2013-01-01

    Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled

  18. Effects of air vessel on water hammer in high-head pumping station

    Science.gov (United States)

    Wang, L.; Wang, F. J.; Zou, Z. C.; Li, X. N.; Zhang, J. C.

    2013-12-01

    Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled.

  19. UO2-PuO2 critical experiments based on a coupled NJOY/AMPX-II/HAMMER-TECHNION system

    International Nuclear Information System (INIS)

    Fernandes, M.A.R.

    1990-01-01

    The performance of the HAMMER-TECHNION system in the criticality analysis of mixed oxide (UO sub(2)-PuO sub(2)) fuel pins clad with Zircaloy-2 and having light water as moderator was analyzed in this work. The basic nuclear data libraries for the HAMMER-TECHNION have been generated by processing the ENDF/B-IV and JENDL-2 nuclear data files with the NJOY system. The question of the effect of Plutonium resonances close to the thermal region on the average thermal parameters was addressed by creating a special version of the HAMMER-TECHNION system with the thermal energy cut-off at 1.855 eV. The final system effective multiplication factor was calculated with the CITATION code by using the homogeneized four-group cross sections generated by the HAMMER-TECHNION system. Results are shown for the original HAMMER-TECHNION thermal cut-off and for the one at 1.855 eV. Besides that, for some selected critical systems, the effect of the resonance interference among the resonances of the Uranium and Plutonium isotopes was addressed by using the ROLAIDS module of the AMPX-II system. The effect of the thermal energy cut-off on the integral parameters of the critical systems was not found to be of extreme importance. (author)

  20. Ulnar hammer syndrome: a systematic review of the literature.

    Science.gov (United States)

    Vartija, Larisa; Cheung, Kevin; Kaur, Manraj; Coroneos, Christopher James; Thoma, Achilleas

    2013-11-01

    Ulnar hammer syndrome is an uncommon form of arterial insufficiency. Many treatments have been described, and debate continues about the best option. The goal of this systematic review was to determine whether ulnar hammer syndrome has an occupational association, to identify the most reliable diagnostic test, and to determine the best treatment modality. A comprehensive literature search was conducted using the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, MEDLINE, CINAHL, and EMBASE. Data from articles meeting inclusion criteria were collected in duplicate. Methodological quality of studies was assessed using the Methodological Index for Nonrandomized Studies scale. Thirty studies were included in the systematic review. No randomized controlled trials were identified. There is low-quality evidence suggestive of an association between exposure to repetitive hand trauma and vibration and ulnar hammer syndrome. Various diagnostic investigations were used, but few were compared, making it difficult to determine the most reliable diagnostic test. Numerous nonoperative and operative treatments were reported. With nonoperative treatment, 12 percent had complete resolution and 70 percent had partial resolution of their symptoms. Of patients treated operatively, 42.5 percent had complete resolution and 42.5 percent had partial resolution of their symptoms. The heterogeneity in study design and outcome measures limits definitive conclusions about occupational association, best diagnostic test, and treatment for ulnar hammer syndrome. However, there is low-quality evidence that suggests that most patients with ulnar hammer syndrome will have partial relief of symptoms with nonoperative treatment, and operative treatment results in complete or partial resolution of symptoms in the majority of cases. Therapeutic, IV.

  1. On HammerCloud and ETF

    CERN Document Server

    Babik, Marian; CERN. Geneva. IT Department

    2017-01-01

    This technical report presents the two major synthetic testing platforms used in WLCG, HammerCloud (HC) and Experiments Test Framework (ETF). It gives an overview of their architecture, components, deployment and operations and discusses the possible commonalities/differences and possible future synergies between the two projects.

  2. Experimental studies of water hammer in propellant feed system of reaction control system

    Directory of Open Access Journals (Sweden)

    Avanish Kumar

    2018-03-01

    Full Text Available Water hammer pressure transient produces large dynamic forces which can damage the pipes and other assemblies in the feed line of a reaction control system (RCS. It has led to the failure of pressure transducers monitoring the manifold pressure in the feed line of RCS. Therefore, water hammer studies have been carried out to understand its effect in feed line. Feedline system has been simplified to develop a mathematical model and experiments have been carried out at extensive levels. The mathematical model was developed considering pipe of uniform c/s and moving liquid-gas interface. The experimental studies have been done using water as working medium instead of actual propellant. The studies showed that rate of pressurization have a very critical role on the water hammer amplitude. Sensitivity studies have been also carried out to study the effect of density, friction and initial liquid column length on water hammer amplitude. Keywords: Water hammer, Reaction control system (RCS, Propellant feed system, Experimental study, Testing

  3. Water hammer calculation and analysis in main feedwater system of PWR nuclear power plants

    International Nuclear Information System (INIS)

    Wang Xin; Han Weishi

    2010-01-01

    The main feedwater system of a nuclear power plant is an important part in ensuring the cooling of the steam generator. Moreover, it is the main pipe section where water hammers frequently occur. Studying the regular patterns of water hammers to the main feedwater system is significant to the stable operation of the system. The paper focuses on the study of water hammers through Flowmaster's transient calculating function to establish a mathematical model with boundary conditions such as a feedwater pump, control valves, etc.; calculation of the water hammers pressure when feedwater pumps and control valves shut down; exporting the instantaneous change in solution of pressure. Combined with engineering practical examples, the conclusions verify the viability of calculating the water hammers pressure through Flowmaster's transient function, increasing the periods of closure of control valves and feedwater pumps control water hammers effectively, changing the intervals of closing signals to feedwater pumps and control valves to relieve hydraulic impact. This could be a guideline for practical engineering design and system optimization. (authors)

  4. A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from Alectoris barbara (Aves: Phasianidae) from the Canary Islands (Spain).

    Science.gov (United States)

    Fernández-Alvarez, A; Modry, D; Foronda, P

    2016-05-01

    The present study was conducted with the objective of identifying the species of Eimeria present in a cynegetic farm. A new coccidian (Apicomplexa: Eimeriidae) species is described from Barbary partridge, Alectoris barbara, from the Canary Islands. Experimental infections were carried out in order to determine the prepatent period, sporulation time, site of infection, and morphology of endogenous stages. One species is described as new. Eimeria barbarae n. sp. has ellipsoidal oocysts, 20.0 × 14.4 (16-23 × 13-16) μm, with a shape-index (SI) of 1.39. Sporocysts are almond-shaped, 9.0 × 5.4 (6.5-11 × 4.5-6) μm, SI = 1.56. The endogenous development takes place along the intestine. The present study showed that E. barbarae causes severe pathologies in A. barbara chickens, with impact on their health condition. Control strategies needs to be implemented to reduce the loss due to coccidiosis at studied farm.

  5. The significance of water hammer events to public dose from reactor accidents: A probabilistic assessment

    International Nuclear Information System (INIS)

    Amico, P.J.; Ferrell, W.L.; Rubin, M.P.

    1984-01-01

    A probabilistic assessment was made of the effects on public dose of water hammer events in LWRs. The analysis utilized actual historical water hammer data to determine if the water hammer events contributed either to system failure rates or initiating event frequencies. Representative PRAs were used to see if changes in initiating events and/or system failures caused by water hammer resulted in new values for the dominant sequences in the PRAs. New core melt frequencies were determined and carried out to the subsequent increase in public dose. It is concluded that water hammer is not a significant problem with respect to risk to the public for either BWRs or PWRs. (orig./HP)

  6. Dynamic shock wave: hammer blow

    International Nuclear Information System (INIS)

    Lackme, Claude

    1978-01-01

    The general properties of shocks, their generation and the conditions of reflexion to an interface are dealt with in turn. By then applying these concepts to a liquid column and its environment (wall, free area, closing devices) the hammer blow is presented as being a relatively weak shock [fr

  7. Validation of CATHENA MOD-3.5/Rev0 for single-phase water hammer

    International Nuclear Information System (INIS)

    Beuthe, T.G.

    2000-01-01

    This paper describes work performed to validate the system thermalhydraulics code CATHENA MOD-3.5c/Rev0 for single-phase water hammer. Simulations were performed and are compared quantitatively against numerical tests and experimental results from the Seven Sisters Water Hammer Facility to demonstrate CATHENA can predict the creation and propagation of pressure waves when valves are opened and closed. Simulations were also performed to show CATHENA can model the behaviour of reflected and transmitted pressure waves at area changes, dead ends, tanks, boundary conditions, and orifices in simple and more complex piping systems. The CATHENA results are shown to calculate pressure and wave propagation speeds to within 0.2% and 0.5% respectively for numerical tests and within 3.3% and 5% for experimental results respectively. These results are used to help validate CATHENA for use in single-phase water hammer analysis. They also provide assurance that the fundamental parameters needed to successfully model more complex forms of water hammer are accounted for in the MOD-3.5c/Rev0 version of CATHENA, and represent the first step in the process to validate the code for use in modelling two-phase water hammer and condensation-induced water hammer. (author)

  8. Hazardous Materials Management and Emergency Response (HAMMER)

    Data.gov (United States)

    Federal Laboratory Consortium — The Volpentest Hazardous Materials Management and Emergency Response (HAMMER) Federal Training Center is a safety and emergency response training center that offers...

  9. Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seungchan; Yoon, Dukjoo [Korea Hydro and Nuclear Power Co., LTd, Daejeon (Korea, Republic of); Lee, Dooyong [Seoul National Univ., Seoul (Korea, Republic of)

    2013-05-15

    Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above.

  10. Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

    International Nuclear Information System (INIS)

    Lee, Seungchan; Yoon, Dukjoo; Lee, Dooyong

    2013-01-01

    Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above

  11. A study of water hammer phenomena in a one-component two-phase bubbly flow

    International Nuclear Information System (INIS)

    Fujii, Terushige; Akagawa, Koji

    2000-01-01

    Water hammer phenomena caused by a rapid valve closure, that is, shock phenomena in two-phase flows, are an important problem for the safety assessment of a hypothetical LOCA. This paper presents the results of experimental and analytical studies of the water hammer phenomena in a one-component tow-phase bubbly flow. In order to clarify the characteristics of water hammer phenomena, experiments for a one-component two-phase flow of Freon R-113 were conducted and a numerical simulation of pressure transients was developed. An overall picture of the water hammer phenomena in a one-component two-phase flow is presented an discussed. (author)

  12. Counterevidence to the ion hammering scenario as a driving force for the shape elongation of embedded nanoparticles

    Science.gov (United States)

    Amekura, H.; Okubo, N.; Tsuya, D.; Ishikawa, N.

    2017-08-01

    Counterevidence is provided in the ion-hammering scenario as a driving force for the shape elongation of embedded nanoparticles (NPs) under swift heavy ion irradiation (SHII). Ion-induced compaction and the hammering, which are both induced in silica under SHII, dominate at low and high fluences, respectively, causing a crossover between them around a fluence of ˜4 × 1012 ions/cm2. Nevertheless, the shape elongation of NPs detected by the optical dichroism exhibits nearly linear dependence in a wide fluence range between ˜1 × 1011 and 2 × 1013 ions/cm2, indicating that the hammering does not play an important role.

  13. Water hammer due to rapid bubble growth at a severe accident

    International Nuclear Information System (INIS)

    Aya, Izuo; Adachi, Masaki; Shiozaki, Koki; Inasaka, Fujio

    2000-01-01

    On a severe accident of the light water reactor (LWR), by steam explosion and so forth due to hydrogen formation by water-metal reaction and direct contact of molted core with water, it is presumed that a lot of vapor forms for a short time in water at reactor vessel and under part of containment vessel. This study aims at and carries out, under reference of the conventional study results, experimental elucidation on coherence of water block motion due to rapid bubble growth, proposal on reduction method of water hammering, development of water hammer estimating method in an actual reactor, and proposal for upgrading of reliability on severe accident evaluation. In 1998 fiscal year, an 'Experimental apparatus on water hammering elements on sever accident' simulated rapid bubble growth due to steam explosion by injecting high pressure air into water was produced to carry out its function test. As a result of the carried out function tests, extreme water hammering phenomena were observed, by which validity of establishment on the study objects could be confirmed. (G.K.)

  14. STUDY ON OPERATING CHARACTERISTECS OF WATER HAMMER GENERATING DEVICE FOR TREATMENT OF MICROORGANISM

    Science.gov (United States)

    Hamada, Tatsuhisa; Endo, Shigekatsu; Oda, Akira; Shimizu, Yasushi

    The phenomenon that has been actualized due to the water quality deterioration because of the inflow of drainage and the industrial wastewater includes the phenomenon that is called water-bloom generated in the freshwater environment made a eutrophic. This is becoming a serious problem to secure the water.Mixing with the drinking water has already been confirmed, and the generation of water-bloom is becoming a big social problem, and fundamental measures have not been established yet.On the other hand, authors are proving the pressure to be a fast the pressure speed of the impact pressure by the water hammer and effective in the destruction of the blue-green algae.In this studies, the hydraulics flow characteristics of an effective water hammer pressure generator to the shredding of the water-bloom cell were examined.As a result, there was a boundary in the region where the water hammer was generated by length and the water supply head of conduit, and the water hammer pressure was able to be understood to be influenced according to the angle of the valve that generated the water hammer in addition in the water hammer generator.The demonstration in the locale was confirmed based on these and the scale etc. of an effective device to the doing water-bloom processing were able to be confirmed by continuous running.

  15. Barbara Fraticelli, Paradigmi urbani

    Directory of Open Access Journals (Sweden)

    Lucia Faienza

    2017-05-01

    Full Text Available I saggi raccolti all’interno del volume Paradigmi urbani. Forme e scritture della città contemporanea, di Barbara Fraticelli, offrono un variegato excursus storico e geografico sulle rappresentazioni della città in letteratura, dal Rinascimento sino ai nostri giorni. Gli autori compresi nella raccolta conducono il lettore da Lisbona a Bucarest, da Calcutta a Nuoro: l’autrice delinea un panorama che congiunge generi letterari e punti di vista molteplici, con una particolare cura della sezione dedicata alle rappresentazioni della città di Bucarest.

  16. Effects of valve characteristics and pipe diameter on water hammer phenomena

    International Nuclear Information System (INIS)

    Hur, J.; Kim, T. H.; Mun, B. H.; Choi, H. Y.; Lee, K. W.; Noh, T. S.

    2001-01-01

    The water hammer phenomena mean that the dynamic loads are induced on the pipe, the pipe support and the equipments in the system due to the sudden change of the flow velocity inside the pipe. The sudden changes are mainly caused by the valve sudden on/off and pump sudden start/trip. To develop a selection criterion of the parts to be analyzed for the water hammer, the effects of the valve characteristics and pipe diameter on the water hammer are analyzed. The analyses using Method of Characteristics (MOC) show that the effects of the valve pressure difference and the valve opening time are very significant, but the effects of the pipe diameter are not dominant

  17. Ultrasonic/Sonic Rotary-Hammer Drills

    Science.gov (United States)

    Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Kassab, Steve

    2010-01-01

    Ultrasonic/sonic rotary-hammer drill (USRoHD) is a recent addition to the collection of apparatuses based on ultrasonic/sonic drill corer (USDC). As described below, the USRoHD has several features, not present in a basic USDC, that increase efficiency and provide some redundancy against partial failure. USDCs and related apparatuses were conceived for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. They have been described in numerous previous NASA Tech Briefs articles. To recapitulate: A USDC can be characterized as a lightweight, lowpower, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. A basic USDC includes a piezoelectric stack, an ultrasonic transducer horn connected to the stack, a free mass ( free in the sense that it can bounce axially a short distance between hard stops on the horn and the bit), and a tool bit. The piezoelectric stack creates ultrasonic vibrations that are mechanically amplified by the horn. The bouncing of the free mass between the hard stops generates the sonic vibrations. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that unlike in conventional twist drilling, little applied axial force is needed to make the apparatus advance into the material of interest. There are numerous potential applications for USDCs and related apparatuses in geological exploration on Earth and on remote planets. In early USDC experiments, it was observed that accumulation of cuttings in a drilled hole causes the rate of penetration of the USDC to decrease steeply with depth, and that the rate of penetration can be increased by removing the cuttings. The USRoHD concept provides for

  18. Method to study water hammer with fluid-structure interaction in spatial pipe

    International Nuclear Information System (INIS)

    Xi Zhide; Ma Jianzhong; Sun Lei

    2013-01-01

    The theory of coupling 4-function models and its solution approach are first introduced in this paper, and the method of CFD to calculate fluid-structure interaction is also introduced. Finally, the model in related reference is applied with this method to simulate the process of water hammer. By CFD calculation for the classical water hammer, the numerical scheme and grid are selected, and the results of CFD are compared with reference. The results show that the method in this paper can be used in more complex pipe system to simulate the water hammer effect. (authors)

  19. Uncertainty and sensitivity analysis of parameters affecting water hammer pressure wave behaviour

    International Nuclear Information System (INIS)

    Kaliatka, A.; Uspuras, E.; Vaisnoras, M.

    2006-01-01

    Pressure surges occurring in pipeline systems may be caused by fast control interference, start up and shut down processes and operation failure. They lead to water hammer upstream the closing valve and cavitational hammer downstream the valve, which may cause considerable damages to the pipeline and the support structures. Appearance of water hammer in thermal-hydraulic systems was widely studied employing different state-of-the-art thermal-hydraulic codes in many organizations. For the analysis water hammer test performed at Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) at Oberhausen was considered. This paper presents the comparison of UMSICHT test facility experiment calculations employing the best estimate system code RELAP5/Mod3.3 to measured water hammer values after fast closure of a valve. The analysis revealed that the calculated first pressure peak, which has the highest value, matches the measured value very well. The performed analysis (as well as any other analyses) as a results of each individual calculation always contains uncertainty owing to initial conditions of installations, errors of measuring systems, errors caused by nodalization of objects at modelling, code correlations, etc. In this connection, results of uncertainty and sensitivity analysis of the initial conditions and code-selected models are shown in the paper. (orig.)

  20. UC Santa Barbara physicist wins prestigious European award

    CERN Document Server

    2003-01-01

    "The prestigious High Energy and Particle Physics Prize of the European Physical Society for 2003 has been awarded to David Gross, a professor of physics and director of the Kavli Institute for Theoretical Physics at the University of California, Santa Barbara. He shares the prize with two other Americans - Frank Wilczek of the Massachusetts Institute of Technology ... and David Politzer of the California Institute of Technology. They are the first Americans to ever receive the award" (1 page).

  1. Mathematical Methodology for New Modeling of Water Hammer in Emergency Core Cooling System

    International Nuclear Information System (INIS)

    Lee, Seungchan; Yoon, Dukjoo; Ha, Sangjun

    2013-01-01

    In engineering insight, the water hammer study has carried out through the experimental work and the fluid mechanics. In this study, a new access methodology is introduced by Newton mechanics and a mathematical method. Also, NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the effect of water-hammer for the protection of pipes of the Emergency Core Cooling System, which is related to the Residual Heat Removal System and the Containment Spray System. This paper includes modeling, the processes of derivation of the mathematical equations and the comparison with other experimental work. To analyze the effect of water-hammer, this mathematical methodology is carried out. This study is in good agreement with other experiment results as above. This method is very efficient to explain the water-hammer phenomena

  2. Mathematical Methodology for New Modeling of Water Hammer in Emergency Core Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seungchan; Yoon, Dukjoo; Ha, Sangjun [Korea Hydro Nuclear Power Co. Ltd, Daejeon (Korea, Republic of)

    2013-05-15

    In engineering insight, the water hammer study has carried out through the experimental work and the fluid mechanics. In this study, a new access methodology is introduced by Newton mechanics and a mathematical method. Also, NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the effect of water-hammer for the protection of pipes of the Emergency Core Cooling System, which is related to the Residual Heat Removal System and the Containment Spray System. This paper includes modeling, the processes of derivation of the mathematical equations and the comparison with other experimental work. To analyze the effect of water-hammer, this mathematical methodology is carried out. This study is in good agreement with other experiment results as above. This method is very efficient to explain the water-hammer phenomena.

  3. A Universal Rig for Supporting Large Hammer Drills: Reduced Injury Risk and Improved Productivity.

    Science.gov (United States)

    Rempel, David; Barr, Alan

    2015-10-01

    Drilling holes into concrete with heavy hammer and rock drills is one of the most physically demanding tasks performed in commercial construction and poses risks for musculoskeletal disorders, noise induced hearing loss, hand arm vibration syndrome and silicosis. The aim of this study was to (1) use a participatory process to develop a rig to support pneumatic rock drills or large electric hammer drills in order to reduce the health risks and (2) evaluate the usability of the rig. Seven prototype rigs for supporting large hammer drills were developed and modified with feedback from commercial contractors and construction workers. The final design was evaluated by laborers and electricians (N=29) who performed their usual concrete drilling with the usual method and the new rig. Subjective regional fatigue was significantly less in the neck, shoulders, hands and arms, and lower back) when using the universal rig compared to the usual manual method. Usability ratings for the rig were significantly better than the usual method on stability, control, drilling, accuracy, and vibration. Drilling time was reduced by approximately 50% with the rig. Commercial construction contractors, laborers and electricians who use large hammer drills for drilling many holes should consider using such a rig to prevent musculoskeletal disorders, fatigue, and silicosis.

  4. Factors analysis of water hammer in FLOWMASTER for main feedwater systems of PWR nuclear power plants

    International Nuclear Information System (INIS)

    Wang Xin; Han Weishi

    2010-01-01

    The main feedwater system of a nuclear power plant (NPP) is an important part in ensuring the cooling of a steam generator. It is the main pipe section where water hammers frequently occur. Studying the regulator patterns of water hammers in the main feedwater systems is significant to the stable operation of the system. This article focuses on a parametric study to avoid the consequences of water hammer effect in PWR by employing a general purpose fluid dynamic simulation software-FLOWMASTER. Through FLOWMASTER's transient calculating functions, a mathematical model is established with boundary conditions such as feedwater pumps, control valves, etc., calculations of water hammer pressure when feedwater pumps and control valves shut down, and simulations during instantaneous changes in water hammer pressure. Combining a plethora of engineering practical examples, this research verified the viability of calculating water hammer pressure through FLOWMASTER's transient functions and we found out that, increasing the periods of closure of control valves and feedwater pumps control water hammers effectively. We also found out that changing the intervals of closing signals to feedwater pumps and control valves aid to relieve hydraulic impact. This could be a guideline for practical engineering design and system optimization. (author)

  5. Optimal Control of the Valve Based on Traveling Wave Method in the Water Hammer Process

    Science.gov (United States)

    Cao, H. Z.; Wang, F.; Feng, J. L.; Tan, H. P.

    2011-09-01

    Valve regulation is an effective method for process control during the water hammer. The principle of d'Alembert traveling wave theory was used in this paper to construct the exact analytical solution of the water hammer, and the optimal speed law of the valve that can reduce the water hammer pressure in the maximum extent was obtained. Combining this law with the valve characteristic curve, the principle corresponding to the valve opening changing with time was obtained, which can be used to guide the process of valve closing and to reduce the water hammer pressure in the maximum extent.

  6. Experiments of condensation-induced water hammers at the UniBw Munich

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas

    2013-01-01

    Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

  7. Experiments of condensation-induced water hammers at the UniBw Munich

    Energy Technology Data Exchange (ETDEWEB)

    Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas [Universitaet der Bundeswehr Muenchen, Neubiberg (Germany). Hydromechanik und Wasserbau

    2013-03-15

    Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

  8. Definitions of hammer toe and claw toe: an evaluation of the literature.

    Science.gov (United States)

    Schrier, Joost C M; Verheyen, Cees C P M; Louwerens, Jan Willem

    2009-01-01

    Lesser toe surgery is among the most conducted interventions in general orthopedic practice. However, the definitions of hammer toe and claw toe are not uniform. The objective of this literature study is to propose clear definitions for these deformities to establish unambiguous communication. A literature search was performed in the PubMed database (May 2006). Of 81 eligible articles, 42 that stated a clear definition of hammer toe or claw toe were selected. In all 35 articles in which hammer toe was clearly defined, flexion in the proximal interphalangeal joint was part of the definition. Seventeen articles (49%) defined hammer toe as a combination of metatarsophalangeal extension and proximal interphalangeal flexion. Thirteen articles showed flexion of the proximal interphalangeal joint as the single criterion. Twenty-three articles with a clear definition of claw toe were selected. Twenty-one articles (91%) showed metatarsophalangeal extension as part of the claw toe deformity. Twelve articles (52%) regarded metatarsophalangeal extension and flexion of the proximal interphalangeal and distal interphalangeal joints as the essential characteristics. Seven articles described a claw toe as metatarsophalangeal extension with flexion in the proximal interphalangeal joint. There are variations in the definitions of lesser toe deformities in the literature. We propose that extension of the metatarsophalangeal joint is the discriminating factor and essential characteristic for claw toe. Claw toe and hammer toe should be characterized by flexion in the proximal interphalangeal joint, which is the single criterion for a hammer toe. The flexibility of these joints could be a basic factor in discriminating between these deformities. The development of these deformities should be regarded as a continuum in the same pathophysiologic process.

  9. Analysis of water hammer in a penstock in the case of valve closure. Part 1: Without pressure losses

    Directory of Open Access Journals (Sweden)

    Hocine HAMMOUM

    2016-04-01

    Full Text Available We develop, in this paper, a method of calculating the water hammer inspired by the graphic construction of Bergeron, which we qualify as analytical method. In helping us of these graphs, we get the relationships that allow calculating the flow rates and pressures along a penstock. The flow of water is carried out by gravity adduction connecting at upstream a storage tank and at downstream a valve. In this first part, we neglect the pressure losses. The study will focus on water hammer-induced by a slow closing of the valve. A practical example will be presented at the end of this work in order to illustrate the exposed method.

  10. Estimation on separation efficiency of aluminum from base-cap of spent fluorescent lamp in hammer crusher unit.

    Science.gov (United States)

    Rhee, Seung-Whee

    2017-09-01

    In order to separate aluminum from the base-cap of spent fluorescent lamp (SFL), the separation efficiency of hammer crusher unit is estimated by introducing a binary separation theory. The base-cap of SFL is composed by glass fragment, binder, ferrous metal, copper and aluminum. The hammer crusher unit to recover aluminum from the base-cap consists of 3stages of hammer crusher, magnetic separator and vibrating screen. The optimal conditions of rotating speed and operating time in the hammer crusher unit are decided at each stage. At the optimal conditions, the aluminum yield and the separation efficiency of hammer crusher unit are estimated by applying a sequential binary separation theory at each stage. And the separation efficiency between hammer crusher unit and roll crush system is compared to show the performance of aluminum recovery from the base-cap of SFL. Since the separation efficiency can be increased to 99% at stage 3, from the experimental results, it is found that aluminum from the base-cap can be sufficiently recovered by the hammer crusher unit. Copyright © 2017. Published by Elsevier Ltd.

  11. Metagenomes from two microbial consortia associated with Santa Barbara seep oil.

    Science.gov (United States)

    Hawley, Erik R; Malfatti, Stephanie A; Pagani, Ioanna; Huntemann, Marcel; Chen, Amy; Foster, Brian; Copeland, Alexander; del Rio, Tijana Glavina; Pati, Amrita; Jansson, Janet R; Gilbert, Jack A; Tringe, Susannah Green; Lorenson, Thomas D; Hess, Matthias

    2014-12-01

    The metagenomes from two microbial consortia associated with natural oils seeping into the Pacific Ocean offshore the coast of Santa Barbara (California, USA) were determined to complement already existing metagenomes generated from microbial communities associated with hydrocarbons that pollute the marine ecosystem. This genomics resource article is the first of two publications reporting a total of four new metagenomes from oils that seep into the Santa Barbara Channel. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Sketches of a hammer-impact, spiked-base, shear-wave source

    Science.gov (United States)

    Hasbrouck, W.P.

    1983-01-01

    Generation of shear waves in shallow seismic investigations (those to depths usually less than 100 m) can be accomplished by horizontally striking with a hammer either the end of a wood plank or metal structure embedded at the ground surface. The dimensioned sketches of this report are of a steel, hammer-impact, spiked-base, shear-wave source. It has been used on outcrops and in a desert environment and for conducting experiments on the effect of rotating source direction.

  13. Evaluation of SPT energy for Donut and Safety hammers using CPT measurements in Egypt

    Directory of Open Access Journals (Sweden)

    Rami M. El-Sherbiny

    2013-12-01

    Full Text Available Standard Penetration Test (SPT blow counts require correction prior to utilization in soil characterization and determination of properties and behavior. Among the most important corrections is the energy correction required to adjust the blow counts to 60% energy efficiency. However, there are no published data supporting commonly used value in Egypt. This paper presents an evaluation of the energy efficiency of the Donut and Safety hammers commonly used in Egypt and the associated energy correction factor. The energy efficiency is estimated by comparing N-values from the SPT to back-calculated N60 values from the Cone Penetration Test (CPT using well established correlations. Results indicate that the energy efficiency of the Donut hammer based on current practice in Egypt is approximately 50%. Thus, the back-calculated energy correction factor is approximately 0.82. For the Safety hammer, results indicate that the energy efficiency is approximately 60%, and the energy correction factor is approximately 1.0.

  14. An analysis on water hammer in liquid injection shutdown system of CANDU-9

    International Nuclear Information System (INIS)

    Kim, T. H.; Heo, J.; Han, S. K.; Choi, H. Y.; No, T. S.

    2000-01-01

    The water hammer analysis code, PTRAN, is used for computation of transient pressures and pressure differentials in the Liquid Injection Shutdown System(LISS) piping network of CANDU-9 to ensure that the design allowables for LEVEL C Service Limit are met for the water hammer loads resulting from the water hammer. The LISS piping network of CANDU-9 has incorporated design improvement in considering the water hammer, such as declining the horizontal part of helium header, and raising the elevation of the overall system piping configuration, etc. The maximum pressure in the LISS piping network is found to be 7.92 MPa(a) at the closed valve in the vent line, which is below the allowable working pressure and the valve design pressure under Level C service conditions. And it is also shown that the maximum pressure in CANDU-9 is much lower than that in CANDU-6

  15. Moving HammerCloud to CERN's private cloud

    CERN Document Server

    Barrand, Quentin

    2013-01-01

    HammerCloud is a testing framework for the Worldwide LHC Computing Grid. Currently deployed on about 20 hand-managed machines, it was desirable to move it to the Agile Infrastructure, CERN's OpenStack-based private cloud.

  16. Modelling of Cold Water Hammer with WAHA code

    International Nuclear Information System (INIS)

    Gale, J.; Tiselj, I.

    2003-01-01

    The Cold Water Hammer experiment described in the present paper is a simple facility where overpressure accelerates a column of liquid water into the steam bubble at the closed vertical end of the pipe. Severe water hammer with high pressure peak occurs when the vapor bubble condenses and the liquid column hits the closed end of the pipe. Experimental data of Forschungszentrum Rossendorf are being used to test the newly developed computer code WAHA and the computer code RELAP5. Results show that a small amount of noncondensable air in the steam bubble significantly affects the magnitude of the calculated pressure peak, while the wall friction and condensation rate only slightly affect the simulated phenomena. (author)

  17. HAMMER, 1-D Multigroup Neutron Transport Infinite System Cell Calculation for Few-Group Diffusion Calculation

    International Nuclear Information System (INIS)

    Honeck, H.C.

    1984-01-01

    1 - Description of problem or function: HAMMER performs infinite lattice, one-dimensional cell multigroup calculations, followed (optionally) by one-dimensional, few-group, multi-region reactor calculations with neutron balance edits. 2 - Method of solution: Infinite lattice parameters are calculated by means of multigroup transport theory, composite reactor parameters by few-group diffusion theory. 3 - Restrictions on the complexity of the problem: - Cell calculations - maxima of: 30 thermal groups; 54 epithermal groups; 20 space points; 20 regions; 18 isotopes; 10 mixtures; 3 thermal up-scattering mixtures; 200 resonances per group; no overlap or interference; single level only. - Reactor calculations - maxima of : 40 regions; 40 mixtures; 250 space points; 4 groups

  18. Physics-Based Pneumatic Hammer Instability Model, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Florida Turbine Technologies (FTT) proposes to conduct research necessary to develop a physics-based pneumatic hammer instability model for hydrostatic bearings...

  19. Management of Hypothenar Hammer Syndrome A Case Report.

    Science.gov (United States)

    Swofford, Brenen P; Swofford, Devon P

    2018-02-09

    BACKGROUND Hypothenar hammer syndrome is a relatively rare disease process caused by repetitive stress or injury to the hypothenar eminence leading to chronic injury to the ulnar artery. This chronic stress (usually as a result of occupational or sport activities) may result in arterial constriction or thickening, which may lead to thrombosis or aneurysm formation. A review of current literature revealed that reports related to management of hypothenar hammer syndrome are limited. CASE REPORT A 33-year-old male without significant past medical history presented with left hand/digit pain, skin discoloration, and coolness of the hand/digits after a mechanical accident experienced 12 hours prior to presentation. Angiography confirmed reduced flow in the ulnar and radial artery with significant spasm of the ulnar artery. Treatment consisted of heparin, nitroglycerin, and papaverine with rapid resolution of symptoms. The patient was discharged on anticoagulation and a calcium channel blocker, with scheduled follow-up. CONCLUSIONS Hypothenar hammer syndrome is a rare disease process which manifests in certain occupations and activities that put undue stress on the hypothenar area. The use of angiography for definitive diagnosis and the use of anticoagulation and calcium channel blockers for treatment should continue to be studied to determine a standard treatment regimen.

  20. Analysis of mixed oxides critical experiments using the Hammer-Technion code with self-shielding treatment by Bondarenko method

    International Nuclear Information System (INIS)

    Abe, Alfredo Y.; Santos, Adimir dos

    1995-01-01

    The present work summarizes the verification of the treatment of self-shielding based on Bondarenko method in HAMMER-TECHNION cell code for the Pu O 2 -U O 2 critical system using JENDL-3 nuclear data library. The results obtained are in excellent agreement with the original treatment of self-shielding employed by HAMMER-TECHNION cell code. (author). 9 refs, 1 fig, 9 tabs

  1. Utilization of the Nelkin model in a Hammer computer code for calculation the reactor parameters

    International Nuclear Information System (INIS)

    Leal, L.C.

    1980-07-01

    The possibility of modifying the HAMMER code, in the thermal part, by changing the thermal neutron scattering Kernel of its library for another one calculated in a subprogramm which can be incorporated to the code, is studied. This subprogramm uses the original version of the Nelkin model instead of its approximation which is used in the HAMMER. It has the advantage of giving the values of the Kernel for any temperature of the reactor for the approximations P 0 , P 1 , P 2 and P 3 . (Author) [pt

  2. Physics-Based Pneumatic Hammer Instability Model, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this project is to develop a physics-based pneumatic hammer instability model that accurately predicts the stability of hydrostatic bearings...

  3. Analisa Pengaruh Water Hammer Terhadap Nilai Strees Pipa Pada Sistem Loading-Offloading PT.DABN

    Directory of Open Access Journals (Sweden)

    Tri Adi Siswanto

    2014-03-01

    Full Text Available Jalur pipa (pipeline merupakan media yang  digunakan sebagai alat transportasi fluida (cair atau gas, mixed of liquid, solid dan fluid-solid mixture. Ada beberapa tahap penting dalam siklus suatu jalur perpipaan yang digunakan sebagai alat transportasi minyak atau gas: desain, konstruksi, operasional dan pemeliharaan, dan terakhir perbaikan. Operasional merupakn proses kemungkinan terbesar terjadinya kegagalan pada suatu jalur perpipaan. Salah satu kegagalan yang mungkin terjadi adalah fenomena water hammaer. Water hammer adalah sebuah fenomena terjadinhya kenaiakan tekanan yang disebabkan oleh terhenti atau dihentikannya aliran di dalam pipa secara mendadak. Hal ini bisa disebabkan oleh operasional penutupan katup yang dilakukan secara tiba-tiba. Pada paper ini akan dijelaskan kajian mengenai pengaruh kenaikan tekanan yang terjadi karena adanya fenomena water hammer terhadap nilai tegangan jalur perpipaan di sisi discharge. Dari hasil perhitungan diketahui bahwa kenaikan tekanan akibat fenomena water hammer sangat mempengaruhi naiknya nilai tegangan pada pipa. Hasil analisa menunjukan bahwa tegangan yang terjadi ketika fenomena water hammer masih dapat diterima, tetapi kenaikan tekanan ketika terjadi fenomena water hammer melebihi dari batas yang diizinkan sehingga perlu dilakukan prosedur penutupan katup yang sesuai untuk menjaga agar pada saat dioperasionalkan pipa dalam kondisi aman.

  4. Water hammer analysis in a water distribution system

    Directory of Open Access Journals (Sweden)

    John Twyman

    2017-04-01

    Full Text Available The solution to water hammer in a water distribution system (WDS is shown by applying three hybrid methods (HM based on the Box’s scheme, McCormack's method and Diffusive Scheme. Each HM formulation in conjunction with their relative advantages and disadvantages are reviewed. The analyzed WDS has pipes with different lengths, diameters and wave speeds, being the Courant number different in each pipe according to the adopted discretization. The HM results are compared with the results obtained by the Method of Characteristics (MOC. In reviewing the numerical attenuation, second order schemes based on Box and McCormack are more conservative from a numerical point of view, being recommendable their application in the analysis of water hammer in water distribution systems.

  5. Santa Barbara, California Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Santa Barbara, California Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST)...

  6. Recurrent Hypothenar Hammer Syndrome: A Case Report.

    Science.gov (United States)

    Adams, Nicholas S; Ford, Ronald D

    2016-10-01

    Hypothenar hammer syndrome (HHS) is a rare cause of digital ischemia and pain caused from repetitive trauma to the palm. Often related to occupational practices, thrombosis and embolization can occur. Treatment is often surgical and involves excision with or without reconstruction. We describe a 55 year-old, male pipe fitter previously diagnosed and treated for HHS with excision and repair using a reversed interpositional vein graft in the mid-1980's. He continued to work in the profession, which he regularly used his palm as a hammer and returned approximately 30 years later with recurrent symptoms of cold intolerance and pain. Angiography confirmed occlusion of the ulnar artery with emboli present distally. The patient was again treated with excision and reconstruction. HHS is an uncommon cause of digital ischemia. Its recurrence is even more rare. To our knowledge, this is the first described case of diagnosed and treated recurrent HHS.

  7. Water hammer reduces fouling during natural water ultrafiltration.

    Science.gov (United States)

    Broens, F; Menne, D; Pothof, I; Blankert, B; Roesink, H D W; Futselaar, H; Lammertink, R G H; Wessling, M

    2012-03-15

    Today's ultrafiltration processes use permeate flow reversal to remove fouling deposits on the feed side of ultrafiltration membranes. We report an as effective method: the opening and rapid closing of a valve on the permeate side of an ultrafiltration module. The sudden valve closure generates pressure fluctuations due to fluid inertia and is commonly known as "water hammer". Surface water was filtrated in hollow fiber ultrafiltration membranes with a small (5%) crossflow. Filtration experiments above sustainable flux levels (>125 l (m2h)(-1)) show that a periodic closure of a valve on the permeate side improves filtration performance as a consequence of reduced fouling. It was shown that this effect depends on flux and actuation frequency of the valve. The time period that the valve was closed proved to have no effect on filtration performance. The pressure fluctuations generated by the sudden stop in fluid motion due to the valve closure are responsible for the effect of fouling reduction. High frequency recording of the dynamic pressure evolution shows water hammer related pressure fluctuations to occur in the order of 0.1 bar. The pressure fluctuations were higher at higher fluxes (higher velocities) which is in agreement with the theory. They were also more effective at higher fluxes with respect to fouling mitigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Muffling Hammer Blows In A Workshop

    Science.gov (United States)

    Thiele, Alfred W.; Gilbert, Jeffrey L.; Gutow, David A.

    1994-01-01

    Sound-deadening bags placed on hammered workpieces. Useful in many workshop situations. Fabricated easily and inexpensively. Bags filled with particles of sand, metal shot, plastic, or glass, then sewn or molded shut. Tailored to fit special configurations of some workpieces. Devices used to deaden print rollers and to reduce vibrations in main-injector inlet manifold of rocket engine.

  9. 2017-2018 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    . Incidentals: $765.00. Other: $441.04. Total: $10,676.95. Comments: From her residence in Fredericton, NB. 2017-2018 Travel Expense Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit Committee.

  10. Development of methodologies for coupled water-hammer analysis of piping systems and supports

    International Nuclear Information System (INIS)

    Kamil, H.; Gantayat, A.; Attia, A.; Goulding, H.

    1983-01-01

    The paper presents the results of an investigation on the development of methodologies for coupled water-hammer analyses. The study was conducted because the present analytical methods for calculation of loads on piping systems and supports resulting from water-hammer phenomena are overly conservative. This is mainly because the methods do not usually include interaction between the fluid and the piping and thus predict high loads on piping systems and supports. The objective of the investigation presented in this paper was to develop methodologies for coupled water-hammer analyses, including fluid-structure interaction effects, to be able to obtain realistic loads on piping systems and supports, resulting in production of more economical designs. (orig./RW)

  11. Shelf evolution along a transpressive transform margin, Santa Barbara Channel, California

    Science.gov (United States)

    Johnson, Samuel Y.; Hartwell, Stephen; Sorlien, Christopher C.; Dartnell, Peter; Ritchie, Andrew C.

    2017-01-01

    High-resolution bathymetric and seismic reflection data provide new insights for understanding the post–Last Glacial Maximum (LGM, ca. 21 ka) evolution of the ∼120-km-long Santa Barbara shelf, located within a transpressive segment of the transform continental margin of western North America. The goal is to determine how rising sea level, sediment supply, and tectonics combine to control shelf geomorphology and history. Morpho­logic, stratigraphic, and structural data highlight regional variability and support division of the shelf into three domains. (1) The eastern Santa Barbara shelf is south of and in the hanging wall of the blind south-dipping Oak Ridge fault. The broad gently dipping shelf has a convex-upward shape resulting from thick post-LGM sediment (mean = 24.7 m) derived from the Santa Clara River. (2) The ∼5–8-km-wide Ventura Basin obliquely crosses the shelf and forms an asymmetric trough with thick post-LGM sediment fill (mean = 30.4 m) derived from the Santa Clara and Ventura Rivers. The basin is between and in the footwalls of the Oak Ridge fault to the south and the blind north-dipping Pitas Point fault to the north. (3) The central and western Santa Barbara shelf is located north of and in the hanging wall of the North Channel–Pitas Point fault system. The concave-up shape of the shelf results from folding, marine erosion, and the relative lack of post-LGM sediment cover (mean = 3.8 m). Sediment is derived from small steep coastal watersheds and largely stored in the Gaviota bar and other nearshore mouth bars. Three distinct upper slope morphologies result from a mix of progradation and submarine landsliding.Ages and rates of deformation are derived from a local sea-level-rise model that incorporates an inferred LGM shoreline angle and the LGM wave-cut platform. Post-LGM slip rates on the offshore Oak Ridge fault are a mini­mum of 0.7 ± 0.1 mm/yr. Slip rates on the Pitas Point fault system are a minimum of 2.3 ± 0.3 mm

  12. Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill

    Science.gov (United States)

    Badescu, Mircea; Sherrit, Stewart; Bao, Xiaogi; Bar-Cohen, Yoseph; Chen, Beck

    2011-01-01

    Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet, as well as, the search for water and other resources. A deep corer, called Auto-Gopher, is currently being developed as a joint effort of the JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher is a wire-line rotary-hammer drill that combines rock breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) that has been developed as an adaptable tool for many of drilling and coring applications. The USDC uses an intermediate free-flying mass to transform the high frequency vibrations of the horn tip into a sonic hammering of a drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher. The lessons learned from testing the ice gopher were implemented into the design of the Auto-Gopher by inducing a rotary motion onto the fluted coring bit. A wire-line version of such a system would allow penetration of significant depth without a large increase in mass. A laboratory version of the corer was developed in the NDEAA lab to determine the design and drive parameters of the integrated system. The design configuration lab version of the design and fabrication and preliminary testing results are presented in this paper

  13. Improving milling and production of a dust-producing unit equipped with hammer mills

    Energy Technology Data Exchange (ETDEWEB)

    Vorotnikov, Ye.G.; Nikiforov, A.A.; Rasputin, O.V.; Sukhunin, V.I.

    1982-01-01

    This paper presents generalized experience for deriving coarse ground coal dust in hammer mills by providing comparison data on improving efficiency of operation of the unit when switching to a coarser-type grind of the fuel. Need to have more precise formulas to calculate grinding potential of hammer mills when using a coarser grind is shown.

  14. Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

    Energy Technology Data Exchange (ETDEWEB)

    Dirndorfer, Stefan

    2017-01-17

    Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

  15. Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

    International Nuclear Information System (INIS)

    Dirndorfer, Stefan

    2017-01-01

    Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

  16. Review of Barbara K. Seeber, Jane Austen and Animals

    Directory of Open Access Journals (Sweden)

    Lucinda Cole

    2015-03-01

    Full Text Available In this review of Barbara K. Seeber's Jane Austen and Animals (Ashgate, 2013 Lucinda Cole summarizes this foundational book and emphasizes the role of animal studies scholars in linking feminism and environmental issues.

  17. Experimental evaluation of ability of Relap5 and DRAKO to calculate water hammer with phase changes

    International Nuclear Information System (INIS)

    Marcinkiewicz, Jerzy; Adamkowski, Adam; Lewandowski, Mariusz

    2007-01-01

    Mechanical loadings on pipe systems caused by water hammer with phase changes make calculation of final forces difficult in nuclear power plants. The common procedure in Sweden is to calculate the water hammer loadings, according to the classical one-dimensional theory of liquid transient flow in pipeline, and then transfer the results to strength analyses of pipeline structure. This procedure assumes that there is quasi-steady response of the pipeline structure to pressure surges - no dynamic interaction between the fluid and the pipeline construction. The hydraulic loadings are calculated with 1-D so-called 'network' programs. Commonly used in Sweden are Relap5 (Mod3.2.2 and higher) and Drako. As a third party accredited inspection body INSPECTA NUCLEAR AB reviews calculations of water hammer loadings. An important question for the reviewer (and also for the users) is knowledge about their ability to calculate the dynamic loadings. While the ability of Relap5 and DRAKO to calculate water hammer without phase changes is relatively well investigated the skills of the programs when phase changes are present need some more attention. The presented work shall be seen as an attempt to illustrate ability of Relap5, and Drako programs to calculate the water hammer loadings with phase changes. A special attention was paid to using of Relap5 for calculation of water hammer pressure surges (including some aspects of influence of discretisation of space on the calculation results). The calculations are compared with experimental results. The experiments have been conducted at a test rig designed and constructed at the Szewalski Institute of Fluid-Flow Machinery of the Polish Academy of Sciences (IMP PAN) in Gdansk, Poland. The comparison of calculated and measured pressures shows some differences, only the first pressure peak, occurring before evaporation is calculated quite exactly. All next coming pressure peaks differ slightly from the measured with respect to amplitude

  18. Structure and Conceptual Design of a Water-Hammering-Type Honsang for Restoration

    Directory of Open Access Journals (Sweden)

    Yong Sam Lee

    2012-06-01

    Full Text Available We analyzed the manufacturing procedure, specifications, repair history, and details of celestial movements of the water-hammering type Honsang (celestial globe. Results from our study on the remaining Honsangs in China and Japan and on the reconstruction models in Korea were applied to our conceptual design of the water-hammering type Honsang. A Honui (armillary sphere and Honsang using the water-hammering method were manufactured in Joseon in 1435 (the 17th year of King Sejong. Jang Yeong-Sil developed the Honsang system based on the water-operation method of Shui yün i hsiang t’ai in China. Water-operation means driving water wheels using a water flow. The most important factor in this type of operation is the precision of the water clock and the control of the water wheel movement. The water-hammering type Honsang in Joseon probably adopted the Cheonhyeong (天衡; oriental escapement device system of Shui yün i hsiang t’ai in China and the overflow mechanism of Jagyeongnu (striking clepsydra in Joseon, etc. In addition to the Cheonryun system, more gear instruments were needed to stage the rotation of the Honsang globe and the sun’s movement. In this study, the water-hammering mechanism is analyzed in the structure of a water clock, a water wheel, the Cheonhyeong system, and the Giryun system, as an organically working operation mechanism. We expect that this study will serve as an essential basis for studies on Heumgyeonggaknu, the water-operating astronomical clock, and other astronomical clocks in the middle and latter parts of the Joseon dynasty.

  19. S-HAMMER: hierarchical attribute-guided, symmetric diffeomorphic registration for MR brain images.

    Science.gov (United States)

    Wu, Guorong; Kim, Minjeong; Wang, Qian; Shen, Dinggang

    2014-03-01

    Deformable registration has been widely used in neuroscience studies for spatial normalization of brain images onto the standard space. Because of possible large anatomical differences across different individual brains, registration performance could be limited when trying to estimate a single directed deformation pathway, i.e., either from template to subject or from subject to template. Symmetric image registration, however, offers an effective way to simultaneously deform template and subject images toward each other until they meet at the middle point. Although some intensity-based registration algorithms have nicely incorporated this concept of symmetric deformation, the pointwise intensity matching between two images may not necessarily imply the matching of correct anatomical correspondences. Based on HAMMER registration algorithm (Shen and Davatzikos, [2002]: IEEE Trans Med Imaging 21:1421-1439), we integrate the strategies of hierarchical attribute matching and symmetric diffeomorphic deformation to build a new symmetric-diffeomorphic HAMMER registration algorithm, called as S-HAMMER. The performance of S-HAMMER has been extensively compared with 14 state-of-the-art nonrigid registration algorithms evaluated in (Klein et al., [2009]: NeuroImage 46:786-802) by using real brain images in LPBA40, IBSR18, CUMC12, and MGH10 datasets. In addition, the registration performance of S-HAMMER, by comparison with other methods, is also demonstrated on both elderly MR brain images (>70 years old) and the simulated brain images with ground-truth deformation fields. In all experiments, our proposed method achieves the best registration performance over all other registration methods, indicating the high applicability of our method in future neuroscience and clinical applications. Copyright © 2013 Wiley Periodicals, Inc.

  20. Study of effect of in-line hydropneumatic accumulators on output characteristics of hydraulic hammer

    Science.gov (United States)

    Redelin, R. A.; Kravchenko, V. A.; Kamanin, Y. N.; Panichkin, A. V.; Bozhanov, A. A.

    2017-10-01

    The article presents the results of studies of the effect of in-line hydropneumatic accumulators on the output parameters of a hydraulic hammer during their joint operation. Based on mathematical modeling, computational experiments were performed and the output characteristics of the hammer, depending on the design and operating parameters of the in-line hydropneumatic accumulators, were obtained. It was established that for the most effective operation of the hammer, the precharge pressure of the pressure line hydropneumatic accumulator should be 70-80% of the working pressure of the hydraulic system. The utilization of a hydropneumatic accumulator without special additional devices in the discharge line is impractical.

  1. Solenoid hammer valve developed for quick-opening requirements

    Science.gov (United States)

    Wrench, E. H.

    1967-01-01

    Quick-opening lightweight solenoid hammer valve requires a low amount of electrical energy to open, and closes by the restoring action of the mechanical springs. This design should be applicable to many quick-opening requirements in fluid systems.

  2. Study of cooling rates during metallic glass formation in a hammer and anvil apparatus

    International Nuclear Information System (INIS)

    Kroeger, D.M.; Coghlan, W.A.; Easton, D.S.; Koch, C.C.; Scarbrough, J.O.

    1982-01-01

    A model is presented of the simultaneous spreading and cooling of the liquid drop in a hammer and anvil apparatus for rapid quenching of liquid metals. The viscosity of the melt is permitted to vary with temperature, and to avoid mathematical complications which would be associated with spatial variation of the viscosity, Newtonian cooling is assumed. From an expression for the force required to spread the specimen, coupled equations for the mechanical energy balance for the system and the heat transfer from the sample to the hearth and hammer were obtained, and solved numerically. The sample reaches its final thickness when the force required to deform it becomes greater than the force exerted on it by the decelerating hammer. The model was fit to measurements of sample thickness versus hammer speed, using the interface heat transfer coefficient, h, as an adjustable parameter. The values of h so obtained vary somewhat with the melt alloy/substrate metal combination. From predicted cooling curves, the effects of hammer speed, sample size, and initial melt temperature on the cooling rate and the efficiency of glass formation can be assessed. Addition of sample superheat shifts the cooling curve relative to the expected position of the time-temperature-transformation curve for formation of crystalline material from the melt, and thus is an effective means of increasing the probability of glass formation in this type of apparatus

  3. Stratified flow instability and slug formation leading to condensation-induced water hammer in a horizontal refrigerant pipe

    International Nuclear Information System (INIS)

    Samuel Martin, C.

    2005-01-01

    Full text of publication follows: An experimental apparatus was designed for the purpose of investigating the phenomenon of condensation-induced water hammer in an ammonia refrigeration system. Water hammer was initiated by introducing warm ammonia gas over static subcooled ammonia liquid placed in a horizontal 146.3 mm diameter carbon steel pipe 6.0 m in length. By means of fast response piezoelectric pressure transducers and a high speed data acquisition system rapid dynamic pressures were recorded whenever a shock event occurred. Moreover, by means of top-mounted diaphragm pressure transducers the speed of liquid slugs propagating along the pipe was determined. The occurrence of condensation induced water hammer depended upon three major variables; namely, (1) initial liquid depth, (2) liquid temperature, and (3) mass flow rate of warm gas. For given liquid depth and temperature, once the warm gas threshold conditions were exceeded shocks occurred with greater magnitude as the mass flow rate of gas input was increased. With adequate subcooling condensation-induced water hammer occurred for initial liquid depths ranging from 25% to 95% of internal pipe diameter. The threshold mass flow rate of warm gas necessary to initiate water hammer was greater as the initial liquid depth was lowered. Based upon experimental results obtained from four pressure transducers located on the top of the test pipe conditions corresponding to bridging were ascertained. For various initial liquid depths the onset of instability from stratified flow to bridging was correlated with the Taitel-Dukler instability criterion. (author)

  4. Hydrocarbon Plume Dynamics in the Worldś Most Spectacular Hydrocarbon Seeps, Santa Barbara Channel, California

    Science.gov (United States)

    Mau, S.; Reed, J.; Clark, J.; Valentine, D.

    2006-12-01

    Large quantities of natural gas are emitted from the seafloor into the coastal ocean near Coal Oil Point, Santa Barbara Channel (SBC), California. Methane, ethane, and propane were quantified in the surface water at 79 stations in a 270 km2 area in order to map the surficial hydrocarbon plume and to quantify air-sea exchange of these gases. A time series was initiated for 14 stations to identify the variability of the mapped plume, and biologically-mediated oxidation rates of methane were measured to quantify the loss of methane in surface water. The hydrocarbon plume was found to comprise ~70 km2 and extended beyond study area. The plume width narrowed from 3 km near the source to 0.7 km further from the source, and then expanded to 6.7 km at the edge of the study area. This pattern matches the cyclonic gyre which is the normal current flow in this part of the Santa Barbara Channel - pushing water to the shore near the seep field and then broadening the plume while the water turns offshore further from the source. Concentrations of gaseous hydrocarbons decrease as the plume migrates. Time series sampling shows similar plume width and hydrocarbon concentrations when normal current conditions prevail. In contrast, smaller plume width and low hydrocarbon concentrations were observed when an additional anticyclonic eddy reversed the normal current flow, and a much broader plume with higher hydrocarbon concentrations was observed during a time of diminished speed within the current gyre. These results demonstrate that surface currents control hydrocarbon plume dynamics in the SBC, though hydrocarbon flux to the atmosphere is likely less dependent on currents. Estimates of air- sea hydrocarbon flux and biological oxidation rates will also be presented.

  5. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    Directory of Open Access Journals (Sweden)

    Yanfei Kou

    2016-01-01

    Full Text Available Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve is proposed in this paper. The mathematic model of water hammer fluctuations is established based on the characteristic line method. Then, boundary conditions of water hammer controlling for mine drainage system are determined and its simplex model is established. The optimization adjustment strategy is solved from the mathematic model of multistage valve-closing. Taking a mine drainage system as an example, compared results between simulations and experiments show that the proposed method and the optimized valve-closing strategy are effective.

  6. Identification of characteristic frequencies of damaged railway tracks using field hammer test measurements

    Science.gov (United States)

    Oregui, M.; Li, Z.; Dollevoet, R.

    2015-03-01

    In this paper, the feasibility of the Frequency Response Function (FRF)-based statistical method to identify the characteristic frequencies of railway track defects is studied. The method compares a damaged track state to a healthy state based on non-destructive field hammer test measurements. First, a study is carried out to investigate the repeatability of hammer tests in railway tracks. By changing the excitation and measurement locations it is shown that the variability introduced by the test process is negligible. Second, following the concepts of control charts employed in process monitoring, a method to define an approximate healthy state is introduced by using hammer test measurements at locations without visual damage. Then, the feasibility study includes an investigation into squats (i.e. a major type of rail surface defect) of varying severity. The identified frequency ranges related to squats agree with those found in an extensively validated vehicle-borne detection system. Therefore, the FRF-based statistical method in combination with the non-destructive hammer test measurements has the potential to be employed to identify the characteristic frequencies of damaged conditions in railway tracks in the frequency range of 300-3000 Hz.

  7. A simple measurement hammer for quantitative reflex studies

    NARCIS (Netherlands)

    Stam, J.; van Leeuwen, J. R.

    1984-01-01

    A reflex hammer for measurement of the mechanical stimulus strength was designed. Combined with standard EMG equipment this instrument permits the study of both stimulus-response relations and latencies of myotatic reflexes. Some results in normal subjects are discussed

  8. Theoretical calculation possibilities of the computer code HAMMER

    International Nuclear Information System (INIS)

    Onusic Junior, J.

    1978-06-01

    With the aim to know the theoretical calculation possibilities of the computer code HAMMER, developed at Savanah River Laboratory, a analysis of the crytical cells assembly of the kind utilized in PWR reactors is made. (L.F.S.) [pt

  9. Barbara Ryder to head Department of Computer Science

    OpenAIRE

    Daniilidi, Christina

    2008-01-01

    Barbara G. Ryder, professor of computer science at Rutgers, The State University of New Jersey, will become the computer science department head at Virginia Tech, starting in fall 2008. She is the first woman to serve as a department head in the history of the nationally ranked College of Engineering.

  10. Water hammer phenomena occurring in nuclear power installations while filling horizontal pipe containing saturated steam with liquid

    Energy Technology Data Exchange (ETDEWEB)

    Selivanov, Y.F.; Kirillov, P.L.; Yefanov, A.D. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1995-09-01

    The potentiality of the water hammer occurrence in nuclear reactor loop components has been considered under the conditions of filling a steam-containing pipeline leg involving horizontal and vertical sections with liquid subcooled to the saturation temperature. As a result of free discharging from the tank, the liquid enters the horizontal pipeline. When the liquid slug formation in the pipeline is fulfilled. The pressure drop being occurred in steam flowing along the pipelines causes the liquid slug to move to the pipeline inlet. When the liquid slug decelerates, a water hammer occurs. This mechanism of water hammer occurrence is tested by experiments. The regimes of the occurrence of multiple considerable water hammers were identified.

  11. Water hammer phenomena occurring in nuclear power installations while filling horizontal pipe containing saturated steam with liquid

    International Nuclear Information System (INIS)

    Selivanov, Y.F.; Kirillov, P.L.; Yefanov, A.D.

    1995-01-01

    The potentiality of the water hammer occurrence in nuclear reactor loop components has been considered under the conditions of filling a steam-containing pipeline leg involving horizontal and vertical sections with liquid subcooled to the saturation temperature. As a result of free discharging from the tank, the liquid enters the horizontal pipeline. When the liquid slug formation in the pipeline is fulfilled. The pressure drop being occurred in steam flowing along the pipelines causes the liquid slug to move to the pipeline inlet. When the liquid slug decelerates, a water hammer occurs. This mechanism of water hammer occurrence is tested by experiments. The regimes of the occurrence of multiple considerable water hammers were identified

  12. A study on the initiation of condensation-induced water hammer in a long horizontal pipe

    International Nuclear Information System (INIS)

    Park, Joo Wan

    1992-02-01

    Condensation-induced water hammer (CIWH) is the most severe and has the highest frequency among the water hammer events occurred in nuclear power plants. Among mechanisms associated with this type of water hammer, the steam and water countercurrent flow in a horizontal pipe is known as the dominant mechanism in Pressurized Water Reactors. The CIWH due to steam-water counter-flow in a long horizontal pipe has been analytically investigated with emphasis on the effect of pipe length, in order to identify the conditions necessary to initiate a water hammer and to provide stability maps describing the zone of water hammer to be avoided with the combination of filling water flowrate and pipe length. Analytical models which can be used to predict the limiting boundaries, upper and lower one, of CIWH initiation have been developed and the calculation results have been compared with the data of an actual incident occurred previously in a nuclear power plant. From the approach used in this study, boundary estimates including simple relationships between critical inlet water flowrates and pipe length-to-diameter on the CIWH initiation in a long horizontal pipe could be made, and several corrective actions to prevent water hammer recurrence could be taken. However, because of the limited understanding of the direct-contact condensation phenomena in the typical range of nuclear power plant operation, it is likely that the overall uncertainty of the analysis results will be high. Therefore, further research on this area including scaling analysis is required

  13. Water hammer prediction and control: the Green's function method

    Science.gov (United States)

    Xuan, Li-Jun; Mao, Feng; Wu, Jie-Zhi

    2012-04-01

    By Green's function method we show that the water hammer (WH) can be analytically predicted for both laminar and turbulent flows (for the latter, with an eddy viscosity depending solely on the space coordinates), and thus its hazardous effect can be rationally controlled and minimized. To this end, we generalize a laminar water hammer equation of Wang et al. (J. Hydrodynamics, B2, 51, 1995) to include arbitrary initial condition and variable viscosity, and obtain its solution by Green's function method. The predicted characteristic WH behaviors by the solutions are in excellent agreement with both direct numerical simulation of the original governing equations and, by adjusting the eddy viscosity coefficient, experimentally measured turbulent flow data. Optimal WH control principle is thereby constructed and demonstrated.

  14. 76 FR 31242 - Revisions to the California State Implementation Plan, Santa Barbara County Air Pollution Control...

    Science.gov (United States)

    2011-05-31

    ... the California State Implementation Plan, Santa Barbara County Air Pollution Control District AGENCY... limited disapproval of revisions to the Santa Barbara County Air Pollution Control District (SBCAPCD... BTU/hr and internal combustion engines with a rated brake horse power of 50 or greater. Under...

  15. Hypothenar hammer syndrome and basilic bypass.

    Science.gov (United States)

    Chander, R K; Phair, J; Oza, P; Patel, M; Balar, N

    2014-12-01

    We report a case of hypothenar hammer syndrome. The case presents necessary diagnostic measures and discusses the etiology of this syndrome. Additionally, the case reviews treatments, which culminated in the eventual use of ulnar artery bypass with autogenous basilica vein to treat and resolve the ischemic fingers of the patient. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  16. Air distribution system with the discharge action in the working cavity of downhole air hammer drills

    Science.gov (United States)

    Timonin, VV; Alekseev, SE; Kokoulin, DI; Kubanychbek, B.

    2018-03-01

    It is proposed to carry out pre-mine methane drainage using underground degassing holes made by downhole air hammer drills. The features of downhole air drills are described. The downhole air drill layout with the simple-shape striking part is presented with its pluses and minuses. The researchers point at available options to eliminate the shortcomings. The improved layout of the downhole air hammer drill is suggested. The paper ends with the test data on the prototype air hammer drill, its characteristics and trial drilling results.

  17. Numerical and in-situ investigations of water hammer effects in Drava river Kaplan turbine hydropower plants

    International Nuclear Information System (INIS)

    Bergant, A; Gregorc, B; Gale, J

    2012-01-01

    This paper deals with critical flow regimes that may induce unacceptable water hammer in Kaplan turbine hydropower plants. Water hammer analysis should be performed for normal, emergency and catastrophic operating conditions. Hydropower plants with Kaplan turbines are usually comprised of relatively short inlet and outlet conduits. The rigid water hammer theory can be used for this case. For hydropower plants with long penstocks the elastic water hammer should be used. Some Kaplan turbine units are installed in systems with long open channels. In this case, water level oscillations in the channels should be carefully investigated. Computational results are compared with results of measurements in recently rehabilitated seven Drava river hydroelectric power plants in Slovenia. Water hammer in the six power plants is controlled by appropriate adjustment of the wicket gates and runner blades closing/opening manoeuvres. Due to very long inflow and outflow open channels in Zlatolicje HPP a special vaned pressure regulating device attenuates extreme pressures in Kaplan turbine flow-passage system and controls unsteady flow in both open channels. Comparisons of results include normal operating regimes. The agreement between computed and measured results is reasonable.

  18. Numerical and in-situ investigations of water hammer effects in Drava river Kaplan turbine hydropower plants

    Science.gov (United States)

    Bergant, A.; Gregorc, B.; Gale, J.

    2012-11-01

    This paper deals with critical flow regimes that may induce unacceptable water hammer in Kaplan turbine hydropower plants. Water hammer analysis should be performed for normal, emergency and catastrophic operating conditions. Hydropower plants with Kaplan turbines are usually comprised of relatively short inlet and outlet conduits. The rigid water hammer theory can be used for this case. For hydropower plants with long penstocks the elastic water hammer should be used. Some Kaplan turbine units are installed in systems with long open channels. In this case, water level oscillations in the channels should be carefully investigated. Computational results are compared with results of measurements in recently rehabilitated seven Drava river hydroelectric power plants in Slovenia. Water hammer in the six power plants is controlled by appropriate adjustment of the wicket gates and runner blades closing/opening manoeuvres. Due to very long inflow and outflow open channels in Zlatoličje HPP a special vaned pressure regulating device attenuates extreme pressures in Kaplan turbine flow-passage system and controls unsteady flow in both open channels. Comparisons of results include normal operating regimes. The agreement between computed and measured results is reasonable.

  19. Impact of industrial hammer mill rotor speed on extraction efficiency and quality of extra virgin olive oil.

    Science.gov (United States)

    Polari, Juan J; Garcí-Aguirre, David; Olmo-García, Lucía; Carrasco-Pancorbo, Alegría; Wang, Selina C

    2018-03-01

    Crushing is a key step during olive oil extraction. Among commercial crushers, the hammer mill is the most widely used due to its robustness and high throughput. In the present work, the impact of hammer mill rotor speed on extraction yield and overall quality of super-high-density Arbosana olive oils were assessed in an industrial facility. Our results show that increasing the rotor speed from 2400rpm to 3600rpm led to a rise in oil yield of 1.2%, while conserving quality parameters. Sensory analysis showed more pungency with increased rotation speed, while others attributes were unaffected. Volatile compounds showed little variation with the differences in crusher speed; however, total phenols content, two relevant secoiridoids, and triterpenoids levels increased with rotor speed. Hammer mill rotor speed is a processing variable that can be tuned to increase the extraction efficiency and modulate the chemical composition of extra virgin olive oil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Testing as a Service with HammerCloud

    CERN Document Server

    Medrano Llamas, Ramón; Elmsheuser, Johannes; Legger, Federica; Sciacca, Gianfranco; Sciabà, Andrea; van der Ster, Daniel

    2014-01-01

    HammerCloud was designed and born under the needs of the grid community to test the resources and automate operations from a user perspective. The recent developments in the IT space propose a shift to the software defined data centres, in which every layer of the infrastructure can be offered as a service. Testing and monitoring is an integral part of the development, validation and operations of big systems, like the grid. This area is not escaping the paradigm shift and we are starting to perceive as natural the Testing as a Service (TaaS) offerings, which allow testing any infrastructure service, such as the Infrastructure as a Service (IaaS) platforms being deployed in many grid sites, both from the functional and stressing perspectives. This work will review the recent developments in HammerCloud and its evolution to a TaaS conception, in particular its deployment on the Agile Infrastructure platform at CERN and the testing of many IaaS providers across Europe in the context of experiment requirements....

  1. The Hammer Award is presented to KSC and 45th Space Wing.

    Science.gov (United States)

    1999-01-01

    KSC's Director of Public Affairs Joe Gordon (left) applauds as Ed Gormel and Chris Fairey are named recipients of the Hammer Award at a special presentation in the IMAX 2 Theater in the Kennedy Space Center Visitor Complex. Presenting the award is Morley Winograd (at the podium), director of the National Partnership for Reinventing Government. The Hammer Award is Vice President Al Gore's special recognition of teams of federal employees who have made significant contributions in support of the principles of the National Partnership for Reinventing Government. This Hammer Award acknowledges the accomplishments of a joint NASA and Air Force team that established the Joint Base Operations and Support Contract (J-BOSC) Source Evaluation Board (SEB). Gormel and Fairey are co-chairs of the SEB. The team developed and implemented the acquisition strategy for establishing a single set of base operations and support service requirements for KSC, Cape Canaveral Air Station and Patrick Air Force Base.

  2. Conceptual design report, Hazardous Materials Management and Emergency Response (HAMMER) Training Center

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, K.E. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-11-09

    For the next 30 years, the main activities at the US Department of Energy (DOE) Hanford Site will involve the management, handling, and cleanup of toxic substances. If the DOE is to meet its high standards of safety, the thousands of workers involved in these activities will need systematic training appropriate to their tasks and the risks associated with these tasks. Furthermore, emergency response for DOE shipments is the primary responsibility of state, tribal, and local governments. A collaborative training initiative with the DOE will strengthen emergency response at the Hanford Site and within the regional communities. Local and international labor has joined the Hazardous Materials Management and Emergency Response (HAMMER) partnership, and will share in the HAMMER Training Center core programs and facilities using their own specialized trainers and training programs. The HAMMER Training Center will provide a centralized regional site dedicated to the training of hazardous material, emergency response, and fire fighting personnel.

  3. Conceptual design report, Hazardous Materials Management and Emergency Response (HAMMER) Training Center

    International Nuclear Information System (INIS)

    Kelly, K.E.

    1994-01-01

    For the next 30 years, the main activities at the US Department of Energy (DOE) Hanford Site will involve the management, handling, and cleanup of toxic substances. If the DOE is to meet its high standards of safety, the thousands of workers involved in these activities will need systematic training appropriate to their tasks and the risks associated with these tasks. Furthermore, emergency response for DOE shipments is the primary responsibility of state, tribal, and local governments. A collaborative training initiative with the DOE will strengthen emergency response at the Hanford Site and within the regional communities. Local and international labor has joined the Hazardous Materials Management and Emergency Response (HAMMER) partnership, and will share in the HAMMER Training Center core programs and facilities using their own specialized trainers and training programs. The HAMMER Training Center will provide a centralized regional site dedicated to the training of hazardous material, emergency response, and fire fighting personnel

  4. Sensitivity and specificity of bell-hammer tear as an indirect sign of partial anterior cruciate ligament rupture on magnetic resonance imaging.

    Science.gov (United States)

    Lefevre, N; Naouri, J F; Bohu, Y; Klouche, S; Herman, S

    2014-05-01

    The main purpose of this study was to evaluate the usefulness of the bell-hammer sign in the diagnosis of partial tears of the anterior cruciate ligament (ACL) of the knee on MRI. A retrospective study was performed including all patients who underwent ACL reconstruction for partial or complete tears from 2008 to 2009. The diagnosis of partial or complete ACL tears was based on the appearance of the ligament bundles and the signal quality on MRI. On arthroscopy, which is considered the gold standard, each bundle was classified as normal, partially or completely torn depending on the extent of the rupture and the quality of the remaining fibres. The study included 312 patients, 83 women and 229 men (mean age 33.3 ± 19.6 years). A diagnosis of a tear was made in all patients on preoperative MRI. Arthroscopy did not show any normal ACL, 247/312 (79.2 %) complete tears and 65/312 (20.8%) partial tears, 50/65 (76.9%) on the anteromedial bundle (AM) and 15/65 (23.1%) the posterolateral bundle. The bell-hammer sign was found on MRI in 13/312 patients (4.5%). It involved 9/65 (13.8%) partial tears, all in the AM bundle, and 4/247 (1.6%) complete tears, significantly more frequent in cases of partial rupture (p hammer sign (sensitivity CI 95% = 23.1 ± 10%, specificity CI 95% = 95.9 ± 2.5%) and with the bell-hammer sign in 23/65 cases (sensitivity CI 95% = 35.4 ± 11%, specificity CI 95% = 93.9 ± 3%). The association of the bell-hammer sign with conventional radiological diagnostic criteria has improved diagnosis performance of MRI for partial tears but not significantly (ns). The most important interest of the bell-hammer sign in the day-to-day clinical work is to suggest partial tears on MRI. It aids making a diagnosis, but its absence does not exclude partial ACL rupture. Diagnostic study, Level II.

  5. Pressure and wall shear stress in blood hammer - Analytical theory.

    Science.gov (United States)

    Mei, Chiang C; Jing, Haixiao

    2016-10-01

    We describe an analytical theory of blood hammer in a long and stiffened artery due to sudden blockage. Based on the model of a viscous fluid in laminar flow, we derive explicit expressions of oscillatory pressure and wall shear stress. To examine the effects on local plaque formation we also allow the blood vessel radius to be slightly nonuniform. Without resorting to discrete computation, the asymptotic method of multiple scales is utilized to deal with the sharp contrast of time scales. The effects of plaque and blocking time on blood pressure and wall shear stress are studied. The theory is validated by comparison with existing water hammer experiments. Copyright © 2016. Published by Elsevier Inc.

  6. Impact of pipes networks simplification on water hammer phenomenon

    Indian Academy of Sciences (India)

    problem; the finite difference method using water hammer and mass oscillation ... Mohamed (2003) introduced the effect of different parameters such as time of valve closure, ..... for computing the water age equivalent diameter, Dew. Dew = ⎡.

  7. Prey selection of a captive Oystercatcher Haematopus ostralegus hammering Mussels Mytilus edulis from the ventral side

    NARCIS (Netherlands)

    Ens, Bruno J.; Alting, D

    1996-01-01

    We studied prey choice of a captive Oystercatcher:hat hammered Mussels from the ventral side. The results replicate previous findings that ventral hammerers select Mussels of intermediate size, select against thick-shelled Mussels, abandon an increasing proportion of Mussels with increasing size and

  8. Analytical study on water hammer pressure in pressurized conduits with a throttled surge chamber for slow closure

    Directory of Open Access Journals (Sweden)

    Yong-liang Zhang

    2010-06-01

    Full Text Available This paper presents an analytical investigation of water hammer in a hydraulic pressurized pipe system with a throttled surge chamber located at the junction between a tunnel and a penstock, and a valve positioned at the downstream end of the penstock. Analytical formulas of maximum water hammer pressures at the downstream end of the tunnel and the valve were derived for a system subjected to linear and slow valve closure. The analytical results were then compared with numerical ones obtained using the method of characteristics. There is agreement between them. The formulas can be applied to estimating water hammer pressure at the valve and transmission of water hammer pressure through the surge chamber at the junction for a hydraulic pipe system with a surge chamber.

  9. 2017-2018 Travel Expense Reports for Barbara Lucille Trenholm ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Chantal Taylor

    Purpose: Board Meetings. Date(s):. 2017-11-19 to 2017-11-22. Destination(s):. Ottawa. Airfare: $630.16. Other. Transportation: $135.19. Accommodation: $638.43. Meals and. Incidentals: $208.98. Other: $0.00. Total: ... Reports for Barbara. Lucille Trenholm, Governor, Chairperson of the. Finance and Audit Committee.

  10. Saturation of plastic deformation by swift heavy ion irradiation: Ion hammering vs. surface effects

    Energy Technology Data Exchange (ETDEWEB)

    Ferhati, Redi; Dautel, Knut; Bolse, Wolfgang [Institut fuer Halbleiteroptik und Funktionelle Grenzflaechen, Universitaet Stuttgart (Germany); Fritzsche, Monika [Helmholtz-Zentrum Dresden-Rossendorf (Germany)

    2012-07-01

    Swift heavy ion (SHI) induced plastic deformation is a subject of current research and scientific discussion. This *Ion Hammering* phenomenon was first observed 30 years ago in amorphous materials like metallic glasses. About 10 years ago, Feyh et al. have shown that stress generation and *Ion Hammering* result in self-organization of thin NiO-films on Si-wafers into a sub-micron lamellae-like structure under grazing angle irradiation. The growth of the lamellae was found to saturate as soon as they have reached a thickness of a few hundreds of nm. Here we show our latest results on the restructuring of pre-patterned thin oxide films by SHI under various irradiation conditions. The experiments were performed by employing (in-situ) scanning electron microscopy, and were complemented by (in-situ) energy dispersive x-ray analysis and atomic force microscopy. As we will show, the saturation behavior can be understood as a competition of *Ion Hammering* and surface energy effects, while the unexpected fact, that the initially crystalline films undergo *Ion Hammering* can possibly be attributed to oxygen loss and thus amorphization during irradiation.

  11. Application of air hammer drilling technology in igneous rocks of Junggar basin

    Science.gov (United States)

    Zhao, Hongshan; Feng, Guangtong; Yu, Haiye

    2018-03-01

    There were many technical problems such as serious well deviation, low penetration rate and long drilling cycle in igneous rocks because of its hardness, strong abrasive and poor drillability, which severely influenced the exploration and development process of Junggar basin. Through analyzing the difficulties of gas drilling with roller bits in Well HS 2, conducting the mechanics experiments about igneous rock, and deeply describing the rock-breaking mechanism of air hammer drilling and its adaptability in igneous rocks, air hammer drilling can realize deviation control and fast drilling in igneous rocks of piedmont zone and avoid the wear and fatigue fracture of drilling strings due to its characteristics of low WOB, low RPM and high frequency impact. Through firstly used in igneous rocks of Well HS 201, compared with gas drilling with cone bit, the average penetration rate and one-trip footage of air hammer drilling respectively increased by more than 2.45 times and 6.42 times while the well deviation was always controlled less than 2 degrees. Two records for Block HS were set up such as the fastest penetration rate of 14.29m/h in Φ444.5mm well hole and the highest one-trip footage of 470.62m in Φ311.2mm well hole. So air hammer drilling was an effective way to realize optimal and fast drilling in the igneous rock formation of Junggar basin.

  12. Analysis of water hammer phenomena - Application to deaerator-feedwater pump node

    International Nuclear Information System (INIS)

    Bigu, Melania; Tenescu, Mircea; Nita, Iulian Pavel

    2008-01-01

    The hydraulic hammer adverse effects are extensively presented in the literature available to those who operate and design installations in which this phenomenon occurs. There are specialized computational programs which evaluate diverse technical aspects which occur in this phenomenon. One must be noticed that not all the technical characteristics and not all effective operating modes which are treated in this paper are covered by existing computational programs. Moreover, even specialized developers of such programs recommend insistently that computational results offered by specialized programs to be verified by specialized technologists with experience in alternative theoretical computations in order to avoid any misinterpretation of results obtained by computational codes. After selective exposures of theoretical fundamentals of the problem there are presented a computational calculation obtained using the specialized calculation code PIPENET (Sunrise System Limited, Cambridge, Great Britain). The PIPENET calculation is compared with a standard computational calculation using theoretical correlations. An evaluation of the differences between those two computational methods is made in order to reveal the capabilities of the computational codes in solving the hydraulic hammering problems. In the first stage we obtained the elastic characteristics of the pipe where the phenomena of hydraulic hammering takes place. There are derivative descriptions of differential equations which describe the physical phenomena. In the second part we carried out a complete system analysis of water hammer effect due to a faulty closing of the four level control valves in steam generators. We compared the highest attended pressure with design pressure of the system. We observed that the design pressure is not overpassed. The analysis concluded that pumps' head protection is a very important parameter against overpressure in the feed water system. (authors)

  13. Computerized Hammer Sounding Interpretation for Concrete Assessment with Online Machine Learning.

    Science.gov (United States)

    Ye, Jiaxing; Kobayashi, Takumi; Iwata, Masaya; Tsuda, Hiroshi; Murakawa, Masahiro

    2018-03-09

    Developing efficient Artificial Intelligence (AI)-enabled systems to substitute the human role in non-destructive testing is an emerging topic of considerable interest. In this study, we propose a novel hammering response analysis system using online machine learning, which aims at achieving near-human performance in assessment of concrete structures. Current computerized hammer sounding systems commonly employ lab-scale data to validate the models. In practice, however, the response signal patterns can be far more complicated due to varying geometric shapes and materials of structures. To deal with a large variety of unseen data, we propose a sequential treatment for response characterization. More specifically, the proposed system can adaptively update itself to approach human performance in hammering sounding data interpretation. To this end, a two-stage framework has been introduced, including feature extraction and the model updating scheme. Various state-of-the-art online learning algorithms have been reviewed and evaluated for the task. To conduct experimental validation, we collected 10,940 response instances from multiple inspection sites; each sample was annotated by human experts with healthy/defective condition labels. The results demonstrated that the proposed scheme achieved favorable assessment accuracy with high efficiency and low computation load.

  14. Parim Claptoni jäljendaja Eestis. Barbara Hendricks Pärnus Promfestil

    Index Scriptorium Estoniae

    2007-01-01

    Eric Claptoni tribuutbändi Classic Clapton kontsertidest 4. ja 5. apr. Tartus ja Tallinnas. Ameerika laulja Barbara Hendricksi kontserdist 7. juunil Pärnu Kontserdimajas (kaastegev rootsi pianist Love Derwinger)

  15. An Analysis of the Impact of Valve Closure Time on the Course of Water Hammer

    Science.gov (United States)

    Kodura, Apoloniusz

    2016-06-01

    The knowledge of transient flow in pressure pipelines is very important for the designing and describing of pressure networks. The water hammer is the most common example of transient flow in pressure pipelines. During this phenomenon, the transformation of kinetic energy into pressure energy causes significant changes in pressure, which can lead to serious problems in the management of pressure networks. The phenomenon is very complex, and a large number of different factors influence its course. In the case of a water hammer caused by valve closing, the characteristic of gate closure is one of the most important factors. However, this factor is rarely investigated. In this paper, the results of physical experiments with water hammer in steel and PE pipelines are described and analyzed. For each water hammer, characteristics of pressure change and valve closing were recorded. The measurements were compared with the results of calculations perfomed by common methods used by engineers - Michaud's equation and Wood and Jones's method. The comparison revealed very significant differences between the results of calculations and the results of experiments. In addition, it was shown that, the characteristic of butterfly valve closure has a significant influence on water hammer, which should be taken into account in analyzing this phenomenon. Comparison of the results of experiments with the results of calculations? may lead to new, improved calculation methods and to new methods to describe transient flow.

  16. Water hammer with column separation : a historical review

    NARCIS (Netherlands)

    Bergant, A.; Simpson, A.R.; Tijsseling, A.S.

    2006-01-01

    Column separation refers to the breaking of liquid columns in fully filled pipelines. This may occur in a water-hammer event when the pressure in a pipeline drops to the vapor pressure at specific locations such as closed ends, high points or knees (changes in pipe slope). The liquid columns are

  17. Potential fatigue strength improvement of AA 5083-H111 notched parts by wire brush hammering: Experimental analysis and numerical simulation

    International Nuclear Information System (INIS)

    Sidhom, Naziha; Moussa, Naoufel Ben; Janeb, Sameh; Braham, Chedly; Sidhom, Habib

    2014-01-01

    Highlights: • Wire brush hammering increases by 20% the AA 5083-H111 notched parts fatigue limit. • Improvement of fatigue strength is related to the fatigue cracks nucleation. • Fatigue strength prediction accounts for wire brush hammering effects. - Abstract: The effects of milling as machining process and a post-machining treatment by wire-brush hammering, on the near surface layer characteristics of AA 5083-H111 were investigated. Surface texture, work-hardening and residual stress profiles were determined by roughness measurement, scanning electron microscope (SEM) examinations, microhardness and X-ray diffraction (XRD) measurements. The effects of surface preparation on the fatigue strength were assessed by bending fatigue tests performed on notched samples for two loading stress ratios R 0.1 and R 0.5 . It is found that the bending fatigue limit at R 0.1 and 10 7 cycles is 20% increased, with respect to the machined surface, by wire-brush hammering. This improvement was discussed on the basis of the role of surface topography, stabilized residual stress and work-hardening on the fatigue-crack network nucleation and growth. The effects biaxial residual stress field and surface work-hardening were taken into account in the finite element model. A multi-axial fatigue criterion was proposed to predict the fatigue strength of aluminum alloy notched parts for both machined and treated states

  18. Wave Stresses in the Anvil Hammer Rods under Impact Including Ram Mass and Deformation Force of Forgings

    Directory of Open Access Journals (Sweden)

    V. M. Sinitskiy

    2016-01-01

    Full Text Available When operating the anvil hammers there occur impacts of die tooling and as a consequence, virtually instantaneous impact stops of motion of drop hammer parts. Such operating conditions come with accelerated failures of the anvil hammer rods because of emerging significant wave stresses. Engineering practice widely uses variation, difference, and integral methods to calculate wave stresses. However, to use them a researcher has to acquire certain skills, and the special programs should be available. The paper considers a method for estimating the wave stress changes in the anvil hammer rods, which is based on the wave equation of the Laplace transform. It presents a procedure for generating differential equations and their solution using the operator method. These equations describe the wave processes of strain and stress propagation in the anvil hammer rod under non-rigid impact with the compliance obstacle of the drop hammer parts. The work defines how the piston and rod mass and also the mechanical and geometric parameters of the rod influence on the stress level in the rod sealing of the hammer ram. Analysis of the results shows that the stresses in the rod sealing are proportional to the total amount of wave stresses caused by the rod and piston impact included in the total weight of the system. The piston influence on the stresses in the rod under impact is in direct proportion to the ratio of its mass to the mass of the rod. Geometric parameters of the rod and speed of drop parts before the impact influence on the stress value as well. It was found that if the time of impact is less than the time of the shock wave running in forward and backward direction, the impact with a compliance obstacle is equivalent to that of with a rigid obstacle, and the dependence of the wave stresses follows the Zhukovsky formula of direct pressure shock. The presented method of stress calculation can be successfully used to select the optimal mass and the rod

  19. Hammering towards QED

    Directory of Open Access Journals (Sweden)

    Jasmin C. Blanchette

    2016-01-01

    Full Text Available This paper surveys the emerging methods to automate reasoning over large libraries developed with formal proof assistants. We call these methods hammers. They give the authors of formal proofs a strong "one-stroke" tool for discharging difficult lemmas without the need for careful and detailed manual programming of proof search.The main ingredients underlying this approach are efficient automatic theorem provers that can cope with hundreds of axioms, suitable translations of richer logics to their formalisms, heuristic and learning methods that select relevant facts from large libraries, and methods that reconstruct the automatically found proofs inside the proof assistants.We outline the history of these methods, explain the main issues and techniques, and show their strength on several large benchmarks. We also discuss the relation of this technology to the QED Manifesto and consider its implications for QED-style efforts.

  20. Hypothenar hammer syndrome: long-term follow-up after ulnar artery reconstruction with the lateral circumflex femoral artery.

    Science.gov (United States)

    de Niet, A; Van Uchelen, J H

    2017-06-01

    In symptomatic patients with hypothenar hammer syndrome, the occluded part of the ulnar artery can be reconstructed with an autologous graft. Venous grafts are used frequently, but they are known for their low patency rate. Arterial grafts show better patency rates than venous grafts in coronary bypass surgery. We performed 11 ulnar artery reconstructions with the descending branch of the lateral circumflex femoral artery and compared these with previously performed venous reconstructions. All patients with an arterial graft reconstruction had a patent graft at a mean follow-up of 63 months. In addition, nine out of 11 patients reported improvement in their symptoms. The patency rate of venous reconstructions in hypothenar hammer syndrome is significantly lower. Arterial grafting for hypothenar hammer syndrome has superior patency compared with venous grafting; we recommend it as the surgical treatment of choice for symptomatic hypothenar hammer syndrome. 4.

  1. Percussive Augmenter of Rotary Drills for Operating as a Rotary-Hammer Drill

    Science.gov (United States)

    Aldrich, Jack Barron (Inventor); Bar-Cohen, Yoseph (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bao, Xiaoqi (Inventor); Scott, James Samson (Inventor)

    2014-01-01

    A percussive augmenter bit includes a connection shaft for mounting the bit onto a rotary drill. In a first modality, an actuator percussively drives the bit, and an electric slip-ring provides power to the actuator while being rotated by the drill. Hammering action from the actuator and rotation from the drill are applied directly to material being drilled. In a second modality, a percussive augmenter includes an actuator that operates as a hammering mechanism that drives a free mass into the bit creating stress pulses that fracture material that is in contact with the bit.

  2. Radon mapping - Santa Barbara and Ventura counties

    International Nuclear Information System (INIS)

    Churchill, R.

    1997-01-01

    Since 1990, the Department of Conservation''s Division of Mines and Geology (DMG) has provided geologic information and conducted several research projects on geology and radon for the California Department of Health Services (DHS) Radon Program. This article provides a brief overview of radon''s occurrence and impact on human health, and summarizes a recent DMG project for DHS that used geologic, geochemical, and indoor radon measurement data to produce detailed radon potential zone maps for Santa Barbara and Ventura counties

  3. A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from Alectoris barbara (Aves: Phasianidae) from the Canary Islands (Spain)

    Czech Academy of Sciences Publication Activity Database

    Fernández-Alvarez, A.; Modrý, David; Foronda, P.

    2016-01-01

    Roč. 115, č. 5 (2016), s. 1817-1825 ISSN 0932-0113 Institutional support: RVO:60077344 Keywords : Coccidia * Eimeria barbarae n. sp * Alectoris barbara * Canary Island Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.329, year: 2016

  4. HAMOC: a computer program for fluid hammer analysis

    International Nuclear Information System (INIS)

    Johnson, H.G.

    1975-12-01

    A computer program has been developed for fluid hammer analysis of piping systems attached to a vessel which has undergone a known rapid pressure transient. The program is based on the characteristics method for solution of the partial differential equations of motion and continuity. Column separation logic is included for situations in which pressures fall to saturation values

  5. Impact of pipes networks simplification on water hammer phenomenon

    Indian Academy of Sciences (India)

    Simplification of water supply networks is an indispensible design step to make the original network easier to be analysed. The impact of networks' simplification on water hammer phenomenon is investigated. This study uses two loops network with different diameters, thicknesses, and roughness coefficients. The network is ...

  6. Project T100 -- Hazardous Materials Management and Emergency Response Training Center (HAMMER)

    International Nuclear Information System (INIS)

    Norton, C.E.

    1994-01-01

    The scope of this Quality Assurance Program Plan (QAPP) is to provide a system of Quality Assurance reviews and verifications on the design and construction of the Hazardous Materials Management and Emergency Response (HAMMER) Training Center, project 95L-EWT-100 at Hanford. The reviews and verifications will be on activities associated with design, procurement, and construction of the HAMMER project which includes, but is not limited to earthwork, placement of concrete, laying of rail, drilling of wells, water and sewer line fabrication and installation, communications systems, fire protection/detection systems, line tie-ins, building and mock-up (prop) construction, electrical, instrumentation, pump and valves and special coatings

  7. Legal IEPs: A Common Sense Approach with Barbara Bateman. [Videotape].

    Science.gov (United States)

    Council for Exceptional Children, Reston, VA. Div. for Learning Disabilities.

    In this 2-hour videotape workshop designed for teachers, administrators, parents, and others, Dr. Barbara Bateman answers many key questions that have been raised about Individualized Education Programs (IEPs) since the 1997 amendments to the Individuals with Disabilities Education Act (IDEA) and the 1999 regulations. The videotape reviews the…

  8. Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Winterer, J.T.; Ghanem, N.; Schaefer, O.; Lehnhardt, S.; Thuerl, C.; Laubenberger, J. [Department of Diagnostic Radiology, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Roth, M. [Center of Geriatric Medicine and Gerontology Freiburg, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Horch, R.E. [Department of Plastic and Hand Surgery, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany)

    2002-10-01

    Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained. (orig.)

  9. Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography

    International Nuclear Information System (INIS)

    Winterer, J.T.; Ghanem, N.; Schaefer, O.; Lehnhardt, S.; Thuerl, C.; Laubenberger, J.; Roth, M.; Horch, R.E.

    2002-01-01

    Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained. (orig.)

  10. Water hammer caused by rapid steam production in a severe accident in a light water reactor

    International Nuclear Information System (INIS)

    Inasaka, Fujio; Adachi, Masaki; Murata, Hiroyuki; Aya, Izuo

    2007-01-01

    We conducted the experimental studies on the water hammer caused by striking of a water mass pushed up by a rapidly growing steam bubble, using a cylindrical model containment vessel of 0.4286 m in diameter. In the experiments, a rapid gas growth was simulated by injecting high-pressure steam into a water pool. It was clarified that coherency of the water mass movement and its water hammer caused by the condensable gas production considerably decreased in comparison with the case of the non-condensable gas production because the rising velocity of the water mass was suppressed due to the steam bubble condensation. On the basis of the data, experimental correlations for estimating the water hammer on the structures in the containment vessel were proposed. (author)

  11. THE LEVEL AND AGE DYNAMICS OF SPORTS ACHIEVEMENTS OF ATHLETES-VETERANS OF THE HAMMER THROW

    Directory of Open Access Journals (Sweden)

    Ivanova Natalya Dmitrievna

    2013-03-01

    Full Text Available The article presents the records of the world and Russian athletes veterans in the hammer throw, starting with the age group 35-39 years and up to age group 100-104 years, and a comparison of the records of veterans subject to an age factor and of the high scores of athletes in the current sports. The aim of the work is to analyze the level and dynamics of the records of the world and Russian athletes, veterans in the hammer throw in each five-year group starting with the age group 35-39 years and up to age group 100-104 years. The novelty of the work consists in comparison of the records of the world and Russia in the hammer throw active athletes and records of veterans with the amendment to the age factor. Analysis of the level and age dynamics of sports achievements of domestic and foreign athletes-throwers older age groups. In the course of the research it is established, that in the throwing hammer, decreasing absolute (without regard to the age factor results, which is largely due to the natural age-related changes in the organism of athletes. Records of the world athletes-veterans compared with the records of active athletes and the transition from each of the five-year group in the following, decline on average in men by 10,0%, among women by 19,3%, in spite of the fact that the weight of the shells in the hammer throw with age decreases. Presented the reasons for the backwardness of Russian athletes older than 35 years of foreign veterans.

  12. IMPACT OF ROCK HARDNESS ON FRAGMENTATION BY HYDRAULIC HAMMER AND CRUSHING IN JAW CRUSHER

    Directory of Open Access Journals (Sweden)

    Trpimir Kujundžić

    2008-12-01

    Full Text Available The physical and mechanical characteristics of intact rocks depend on the way of their formation, sustained deformations and the process of wearing a specific rock has been exposed to. These characteristics have a rather high influence on the technological process of extraction and dressing of mineral raw materials. However, the mechanical characteristics of rocks due to use of explosives for their extraction in the open pit have a more significant impact. The rock blocks extracted by blasting which are larger than the opening of the primary crusher are usually fragmented by hydraulic hammer. The paper presents the results of the testing of impact of rock hardness on fragmentation of rocks by means of hydraulic hammer and during crushing in jaw crusher. The testing was carried out on the rock samples from five quarries. According to the obtained results the hardness has a considerably larger impact on the fragmentation energy by hydraulic hammer than on the crushing energy in jaw crusher.

  13. Water Hammer Modelling and Simulation by GIS

    Directory of Open Access Journals (Sweden)

    K. Hariri Asli

    2012-01-01

    Full Text Available This work defined an Eulerian-based computational model compared with regression of the relationship between the dependent and independent variables for water hammer surge wave in transmission pipeline. The work also mentioned control of Unaccounted-for-Water (UFW based on the Geography Information System (GIS for water transmission pipeline. The experimental results of laboratory model and the field test results showed the validity of prediction achieved by computational model.

  14. Ex Vivo Evaluation of Cementless Acetabular Cup Stability Using Impact Analyses with a Hammer Instrumented with Strain Sensors.

    Science.gov (United States)

    Tijou, Antoine; Rosi, Giuseppe; Hernigou, Philippe; Flouzat-Lachaniette, Charles-Henri; Haïat, Guillaume

    2017-12-27

    The acetabular cup (AC) implant stability is determinant for the success of cementless hip arthroplasty. A method based on the analysis of the impact force applied during the press-fit insertion of the AC implant using a hammer instrumented with a force sensor was developed to assess the AC implant stability. The aim of the present study was to investigate the performance of a method using a hammer equipped with strain sensors to retrieve the AC implant stability. Different AC implants were inserted in five bovine samples with different stability conditions leading to 57 configurations. The AC implant was impacted 16 times by the two hammers consecutively. For each impact; an indicator I S (respectively I F ) determined by analyzing the time variation of the signal corresponding to the averaged strain (respectively force) obtained with the stress (respectively strain) hammer was calculated. The pull-out force F was measured for each configuration. F was significantly correlated with I S (R² = 0.79) and I F (R² = 0.80). The present method has the advantage of not modifying the shape of the hammer that can be sterilized easily. This study opens new paths towards the development of a decision support system to assess the AC implant stability.

  15. Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

    NARCIS (Netherlands)

    Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

    2011-01-01

    Fluid-structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

  16. Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

    NARCIS (Netherlands)

    Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

    2012-01-01

    Fluid–structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

  17. Current experience and a new modeling on water hammer due to steam condensation in PWR secondary system

    International Nuclear Information System (INIS)

    Kawanishi, K.; Kasahara, J.; Ueno, T.; Suzuta, T.

    1998-01-01

    There have been possibilities to occur water hammer in pipelines of turbine system for nuclear or fossil fuel power plants. According to the NUREG report, approximately 150 events have been reported since 1969, we also have an experience recently. Water hammer occurs due to sudden steam condensation with pressure pulse. This kind of pressure pulses has been made by alternative producing and condensing of steam slug in the pipe and its frequency relates subcooling and pipe structures. This paper presents our current experience on water hammer with some experimental studies. The present experiment has been performed to obtain the data base for evaluating the pressure pulses. The test pipe was horizontal tubes with dead end connected to vertical tube which simulating drain line in PWR secondary system. The main results are shown as follows; Magnitude of pressure pulse depends drain velocity and initial subcooling. Pipe structure effects on the frequency and continual time of water hammer phenomenon. A new modeling for quantitative explanation of the phenomena is also presented

  18. Research on water hammer forces caused by rapid growth of bubbles at severe accidents of water cooled reactors

    International Nuclear Information System (INIS)

    Inasaka, Fujio; Adachi, Masaki; Aya, Izuo

    2004-01-01

    At severe accidents of Water Cooled Reactors a great deal of gas is expected to be produced in a short time within the water of lower part of nuclear pressure vessel and containment vessel caused by hydrogen production with a metal water reaction and steam explosions with direct contact of melting core and water. Water hammer forces caused by rapid growth of bubbles shall work on the wall of containment vessel and affect its integrity. Coherency of water block movement is not clear, whether simultaneous or in the same direction. Water block behavior and water hammer forces caused by rapid growth of bubbles have been tested using a modified scale model and analyzed to obtain experimental correlated equation to estimate water block's rising distance and velocity from water hammer data. Numerical analysis using RELAP5-3D (Reactor Excursion and Leak Analysis Program) has been conducted to evaluate water hammer forces and makes clear its modifications needed. (T. Tanaka)

  19. Experimental study on the simple water hammer pump; Kan`igata water hammer pump ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Muto, M; Ushiyama, I [Ashikaga Institute of Technology, Tochigi (Japan)

    1997-11-25

    Outlined herein are experimental results with a water hammer pump. It is a unique pump in that it depends only on potential energy of water to pump-up water. Water flows downwards from a reservoir at a high position into the pump , and is released from the exhaust valve. When velocity of water flowing in the pipe reaches a certain level, hydraulic force exceeds gravity of the exhaust valve to rapidly closes it, which is accompanied by rapid increase in pressure in the pump. High-pressure water flows into the air chamber, after pushing up the lifting valve, to compress air in the chamber. The lifting valve is closed, when pressure in the air chamber exceeds that in the pump, to pump up water in the chamber through the lifting pipe. Closure of the lifting valve produces a negative pressure within the pump, which, together with gravity of the exhaust valve, opens the valve again. The pump lifts water at 1.64l/min under the conditions of head: 3m and lift: 6m at an efficiency of 48.1%. 1 ref., 4 fig., 2 tab.

  20. Water hammer caused by rapid gas production in a severe accident in a light water reactor

    International Nuclear Information System (INIS)

    Inasaka, Fujio; Adachi, Masaki; Aya, Izuo; Nariai, Hideki; Shiozaki, Kohki

    2005-01-01

    We investigated the water hammer caused by striking of water mass pushed up by a rapidly growing bubble and its scale effects using two cylindrical model containment vessels of 1.0 and 0.428 m diameters. We also closely observed the movement of water mass and the growing bubble in the vessels. In these experiments, rapid bubble growth was simulated by injecting high-pressure air into a water pool. It was clarified that the water mass was pushed up without any air penetration until the water level reached a certain elevation. On the basis of all data, experimental correlations for estimating the height and striking velocity of the water mass with coherency were proposed, and the water hammer pressure for exerting large forces on the structures was quantitatively evaluated. (author)

  1. The hammer QSD-quick stop device for high speed machining and rubbing

    Science.gov (United States)

    Black, J. T.; James, C. R.

    1980-01-01

    A quick stop device (QSD) was designed for use in orthogonal machining and rubbing experiments. QSD's are used to obtain chip root samples that are representative of the deformation taking place during dynamic (actual) cutting conditions. These 'frozen' specimens are helpful in examining the plastic deformation that occurs in the regions of compression and shear which form the chip; the secondary shear at the tool-chip interface; and the nose ploughing/flank rubbing action which operates on the newly machined surface. The Hammer QSD employs a shear pin mechanism, broken by a flying hammer, which is traveling at the same velocity as the workpiece. The device has been successfully tested up to 6000 sfpm (30.48 m/sec).

  2. Ruth Rendell and Barbara Vine – family matters

    OpenAIRE

    Peters, F

    2017-01-01

    This article traces themes and preoccupations that work across Ruth Rendell’s work, writing both as Rendell and also as Barbara Vine. It investigates the ways in which the\\ud use of a pseudonym allows her to delve deeper into areas that she also explores as Rendell – the dysfunctional family and heredity, both in relation to physical disease and the fruitless search for origins, the latter discussed by her through the lens of Freudian psychoanalysis.

  3. The influence of the non-Newtonian properties of blood on blood-hammer through the posterior cerebral artery.

    Science.gov (United States)

    Tazraei, Pedram; Riasi, Alireza; Takabi, Behrouz

    2015-06-01

    This work investigates a two dimensional numerical analysis of blood hammer through the posterior cerebral artery. The non-Newtonian and usual Newtonian blood models are compared in the case of blood hammer through the posterior cerebral artery to quantify the differences between the models. In this way, a validated CFD simulation is used to study non-Newtonian shear-thinning effects of blood. The governing equations for the modeling of two-dimensional transient flow are solved using a combination of characteristics and central finite difference methods, respectively for the hyperbolic and parabolic parts. Herein, the non-Newtonian viscosity characteristic of blood is incorporated by using the Carreau model. To convert the nonlinear terms available in the characteristics equation into the linear ones, the Newton-Kantorovich method is implemented. The verification and validation of the numerical results are carried out in detail. Hemodynamic characteristics of blood hammer through the posterior cerebral artery are derived with both the Newtonian and non-Newtonian models, and the results are meticulously compared and discussed. The results show that when blood hammer occurs, the non-Newtonian properties greatly influence the velocity and shear stress profiles. At the early stages of blood hammer, there is a 64% difference between magnitudes of wall shear stress in these two models, and the magnitude of the wall shear stress for the shear-thinning blood flow is lower than the Newtonian one. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. A Hybrid Resynthesis Model for Hammer-String Interaction of Piano Tones

    Directory of Open Access Journals (Sweden)

    Jensen Kristoffer

    2004-01-01

    Full Text Available This paper presents a source/resonator model of hammer-string interaction that produces realistic piano sound. The source is generated using a subtractive signal model. Digital waveguides are used to simulate the propagation of waves in the resonator. This hybrid model allows resynthesis of the vibration measured on an experimental setup. In particular, the nonlinear behavior of the hammer-string interaction is taken into account in the source model and is well reproduced. The behavior of the model parameters (the resonant part and the excitation part is studied with respect to the velocities and the notes played. This model exhibits physically and perceptually related parameters, allowing easy control of the sound produced. This research is an essential step in the design of a complete piano model.

  5. Estimation of the effectiveness of the destruction of natural stone oversized by a hydraulic hammer

    Directory of Open Access Journals (Sweden)

    V.G. Kravets

    2017-12-01

    Full Text Available The experience of mining operations shows that even with the application of progressive methods of drilling, it is impossible to completely exclude the output of a large fraction (oversized. The percentage of oversized mass emissions from the blasting mass depending on the mining and geological conditions may vary from 5 to 20 percent. Catching an oversized piece into the receiving slit of the main crusher is associated with stopping the whole technological chain of the enterprise. Sharpening of oversized pieces of the work area during conducting of extraction or overturning works leads to a decrease in the efficiency of mining operations. Crushing of oversized materials to the required sizes can be carried out in an explosive way (by a bore or overhead charge or by non-explosive methods, most of which are based on mechanical destruction under the action of local dynamic stresses that cause stress exceeding the resistance of internal bonds in the rock. To date, manufacturers are offered many types of shock mechanisms, based on the transformation of various types of energy (from gravitational, to the energy of chemical processes into mechanical. For a number of reasons, mostly economic, to date, the most common way is the mechanical method of the destruction of oversized beams using hydraulic and hydro pneumatic hammer. That is why the work considers the main factors influencing the performance of the hydraulic hammer, among which – the specific energy consumption of the oversize and the main parameters of the hydraulic engine passport on the basis of the excavator. In the publication the power law of the hydraulic hammer changes in dependence of the size of the oversized. Also, the basic parameters of the JCB JS235 HD excavator passport are defined in the work with the use of the INDECO HP 1500 hammer hammer.

  6. Sliding pressure control valve for pneumatic hammer drill

    Science.gov (United States)

    Polsky, Yarom [Albuquerque, NM

    2011-08-30

    A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.

  7. Cavitation luminescence in a water hammer: Upscaling sonoluminescence

    Science.gov (United States)

    Su, C.-K.; Camara, C.; Kappus, B.; Putterman, S. J.

    2003-06-01

    Oscillatory acceleration and deceleration of a column of water leads to a pipe hammer as well as cavitation. With a small amount of xenon gas dissolved in the water, we can detect a stream of predominantly ultraviolet subnanosecond flashes of light which are attributed to collapsing bubbles. The observed emission can exceed 108 photons for a single collapse and has a peak power over 0.4 W.

  8. Water hammer with fluid-structure interaction in thick-walled pipes

    NARCIS (Netherlands)

    Tijsseling, A.S.

    2007-01-01

    A one-dimensional mathematical model is presented which describes the acoustic behaviour of thick-walled liquid-filled pipes. The model is based on conventional water-hammer and beam theories. Fluid–structure interaction (FSI) is taken into account. The equations governing straight pipes are derived

  9. Fluid dynamic interaction between water hammer and centrifugal pumps

    International Nuclear Information System (INIS)

    Ismaier, A.; Schluecker, E.

    2009-01-01

    Centrifugal pumps generate in piping systems noticeable pressure pulsations. In this paper the dynamic interaction between water hammer and pressure pulsations is presented. The experimental investigations were performed at a piping system with nominal diameter DN 100 (respectively NPS 4) and 75 m total length, built at the Institute for Process Technology and Machinery. Different measurements at this testing facility show that pulsating centrifugal pumps can damp pressure surges generated by fast valve closing. It is also shown that 1-dimensional fluid codes can be used to calculate this phenomenon. Furthermore it is presented that pressure surges pass centrifugal pumps almost unhindered, because they are hydraulic open.

  10. Theoretical analysis and design of hydro-hammer with a jet actuator: An engineering application to improve the penetration rate of directional well drilling in hard rock formations.

    Science.gov (United States)

    He, Jiang-Fu; Liang, Yun-Pei; Li, Li-Jia; Luo, Yong-Jiang

    2018-01-01

    Rapid horizontal directional well drilling in hard or fractured formations requires efficient drilling technology. The penetration rate of conventional hard rock drilling technology in horizontal directional well excavations is relatively low, resulting in multiple overgrinding of drill cuttings in bottom boreholes. Conventional drilling techniques with reamer or diamond drill bit face difficulties due to the long construction periods, low penetration rates, and high engineering costs in the directional well drilling of hard rock. To improve the impact energy and penetration rate of directional well drilling in hard formations, a new drilling system with a percussive and rotary drilling technology has been proposed, and a hydro-hammer with a jet actuator has also been theoretically designed on the basis of the impulse hydro-turbine pressure model. In addition, the performance parameters of the hydro-hammer with a jet actuator have been numerically and experimentally analyzed, and the influence of impact stroke and pumped flow rate on the motion velocity and impact energy of the hydro-hammer has been obtained. Moreover, the designed hydro-hammer with a jet actuator has been applied to hard rock drilling in a trenchless drilling program. The motion velocity of the hydro-hammer ranges from 1.2 m/s to 3.19 m/s with diverse flow rates and impact strokes, and the motion frequency ranges from 10 Hz to 22 Hz. Moreover, the maximum impact energy of the hydro-hammer is 407 J, and the pumped flow rate is 2.3 m3/min. Thus, the average penetration rate of the optimized hydro-hammer improves by over 30% compared to conventional directional drilling in hard rock formations.

  11. Computational models to determine fluiddynamical transients due to condensation induced water hammer (CIWH)

    International Nuclear Information System (INIS)

    Swidersky, Harald; Schaffrath, Andreas; Dudlik, Andreas

    2012-01-01

    Condensation induced water hammer ('condensation hammer', CIWH) represent a dangerous phenomenon in pipings, which can endanger the pipe integrity. If they cannot be excluded, they have to be taken into account for the integrity proof of components and pipe structures. Up to now, there exists no substantiated model, which sufficiently determines loads due to CIWH. Within the framework of the research alliance CIWA, a tool for estimating the potential and the amount of pressure loads will be developed based on theoretical work and supported by experimental results. This first study discusses used computational models, results of experimental observations and gives an outlook onto future techniques. (orig.)

  12. Thermal-hydraulic calculation and water hammer analysis on CEFR loop system

    International Nuclear Information System (INIS)

    Hao Pengfei; Zhang Xiwen; Cai Weidong; Wang Xuefang

    1997-01-01

    China Experimental Fast Reactor (CEFR) is one of the '863' High-technical Projects. It is necessary to study the hydraulic and thermal Characteristic of CEFR loop system in order to guarantee the safety of operation. The results of the thermal-hydraulic calculation have been given. The main points are as follows: 1. The simplified model is built according to the loop system of CEFR, and the calculation method which is called 'NODE'-'BRANCH' is applied. This method includes two aspects, one is the theoretical analysis that is based on fluid mechanics and heat transfer theory. The other is the engineering calculation. These two aspects are connected in the computation. On the basis of the work mentioned above, the stable state computation is presented. In order to prevent serious damage caused by power failure accident, the courses of surplus reactor heat removing through two different systems have been simulated in the computation. 2. By using the fluid dynamics theory, the simplified model and the equipment boundary conditions of loop system are given. The water hammer computation is processed during the valve closing and pump stopping accidents. Some pictures of water hammer wave are presented, and the most dangerous state in the accident is also given

  13. Water-hammer in the cold leg during an SBLOCA due to cold ECCS injection

    International Nuclear Information System (INIS)

    Ortiz, M.G.; Ghan, L.S.

    1991-01-01

    Water-hammer might occur in the cold leg of pressurized water reactors (PWR) during small break loss-of-coolant accidents (SBLOCA's), when cold emergency core cooling system (ECCS) water is injected into a pipe that may be partially filled with saturated steam. The water may mix with the steam and cause it to condense abruptly. Depending on the flow regime present, slugs of liquid may then be accelerated towards each other or against the piping structure. The possibility of this phenomenon is of concern to us because it may become a dominant phenomenon and change the character of the transient. In performing the code scaling, applicability, and uncertainty study (CSAU) on a SBLOCA scenario, we had to examine the possibility that the transient being analyzed could experience water-hammer and thus depart from the scope of the study. Two criteria for water-hammer initiation were investigated and tested using a RELAP5/MOD3 simulation of the transient. Our results indicated a very low likelihood of occurrence of the phenomenon. 8 refs., 6 figs

  14. Mitigating check valve slamming and subsequentwater hammer events for PPFS using MOC

    International Nuclear Information System (INIS)

    Tian Wenxi; Su Guanghui; Wang Gaopeng; Qiu Suizheng; Xiao Zejun

    2009-01-01

    The method of characteristic (MOC) was adopted to analyze the check valve-induced water hammer behaviors for a Parallel Pumps Feedwater System (PPFS) during the alternate startup process. The motion of check valve disc was simulated using inertial valve model. Transient parameters including the pressure oscillation, local flow velocity and slamming of the check valve disc etc. have been obtained. The results showed that severe slamming between the valve disc and valve seat occurred during the alternate startup of parallel pumps. The induced maximum pressure vibration amplitude is up to 5.0 MPa. The scheme of appending a damping torque to slow down the check valve closing speed was also performed to mitigate of water hammer. It has been numerically approved to be an effective approach. (authors)

  15. Mitigating check valve slamming and subsequentwater hammer events for PPFS using MOC

    Institute of Scientific and Technical Information of China (English)

    TIAN Wenxi; SU Guanghui; WANG Gaopeng; QIU Suizheng; XIAO Zejun

    2009-01-01

    The method of characteristic (MOC) was adopted to analyze the check valve-induced water hammer behaviors for a Parallel Pumps Feedwater System (PPFS) during the alternate startup process. The motion of check valve disc was simulated using inertial valve model. Transient parameters including the pressure oscillation, local flow velocity and slamming of the check valve disc etc. have been obtained. The results showed that severe slamming between the valve disc and valve seat occurred during the alternate startup of parallel pumps. The induced maximum pressure vibration amplitude is up to 5.0 MPa. The scheme of appending a damping torque to slow down the check valve closing speed was also performed to mitigate of water hammer. It has been numerically approved to be an effective approach.

  16. Method for estimating steam hammer effects on swing-check valves during closure

    International Nuclear Information System (INIS)

    Uram, E.M.

    1976-01-01

    Relationships are developed for estimating the disk impact velocity resulting from a free swing closure of swing-check valves in normal flow and for pipe rupture. They derive from a phase-plane solution of the differential equation for the disk motion that accounts for the nature of the valve pressure drop variation due to steam-hammer effects during closure. For closure in normal flow, the method presented has a more correct foundation than that given in reference where a constant, average valve pressure differential based upon the steady-state pressure drop for the total piping system (which has no real relationship to the steam-hammer-induced valve pressure changes during the closure transient) is used in the valve disk motion equation

  17. Influence of pin and hammer mill on grinding characteristics, thermal and antioxidant properties of coriander powder.

    Science.gov (United States)

    Barnwal, P; Singh, K K; Sharma, Alka; Choudhary, A K; Saxena, S N

    2015-12-01

    In present study, influence of grinding (hammer and pin mills) and moisture content (range: 6.4-13.6 % dry basis) on the quality traits of coriander powder were investigated. These include grinding parameters, colour parameters, specific heat, thermal conductivity, thermal diffusivity, glass transition temperature, essential oil, total phenolic content, total flavonoid content and DPPH scavenging (%) of coriander powder. For coriander seed, the geometric properties such as major, medium, minor dimensions, geometric mean diameter, arithmetic mean diameter, sphericity, surface area and volume of coriander seeds increased significantly with increasing moisture (6.4-13.6 % db). For coriander powder, the grinding parameters such as average particle size, volume surface mean diameter and volume mean diameter increased significantly with increasing moisture (6.4-13.6 % db). With the grinding method, the colour attributes of coriander powder such as L-value, a-value, b-value, hue angle and browning index varied significantly. It was observed that the specific heat followed second order polynomial relationship with temperature and moisture whereas thermal conductivity varied linearly with temperature and moisture content. The variation of glass transition temperature with moisture can be best represented in quadratic manner. Total flavonoid content (mg QE/g crude seed extract) and DPPH scavenging % activity of coriander powder is significantly affected by grinding methods. A lower value of specific heat was observed for hammer ground coriander powder as compared to pin mill ground coriander powder. The thermal conductivity of hammer mill ground coriander powder was higher as compared to pin mill ground coriander. It was observed that hammer mill yields more fine coriander powder in comparison to pin mill. The browning index was more in hammer mill ground coriander powder.

  18. Loss of Power and Water Hammer Event at San Onofre, Unit 1, on November 21, 1985

    International Nuclear Information System (INIS)

    1986-01-01

    On November 21, 1985, Southern California Edison's Onofre Nuclear Generating Station, Unit 1, located south of San Clemente, California, experienced a partial loss of inplant ac electrical power while the plant was operating at 60% power. Following a manual reactor trip, the plant lost all inplant ac power for 4 minutes and experienced a severe incidence of water hammer in the feedwater system which caused a leak, damaged plant equipment, and challenged the integrity of the plant's heat sink. The most significant aspect of the event involved the failure of five safety-related check valves in the feed-water system whose failure occurred in less than year, without detection, and jeopardized the integrity of safety systems. The event involved a number of equipment malfunctions, operator errors, and procedural deficiencies. This report documents the findings and conclusions of an NRC Incident Investigation Team sent to San Onofre by the NRC Executive Director for Operations in conformance with NRC's recently established Incident Investigation Program

  19. Follow-up of hearing thresholds among forge hammering workers

    Energy Technology Data Exchange (ETDEWEB)

    Kamal, A.A.; Mikael, R.A.; Faris, R. (Ain Shams Univ., Abbasia, Cairo (Egypt))

    1989-01-01

    Hearing threshold was reexamined in a group of forge hammering workers investigated 8 years ago with consideration of the age effect and of auditory symptoms. Workers were exposed to impact noise that ranged from 112 to 139 dB(A)--at an irregular rate of 20 to 50 drop/minute--and a continuous background noise that ranged from 90 to 94 dB(A). Similar to what was observed 8 years ago, the present permanent threshold shift (PTS) showed a maximum notch at the frequency of 6 kHz and considerable elevations at the frequencies of 0.25-1 kHz. The age-corrected PTS and the postexposure hearing threshold were significantly higher than the corresponding previous values at the frequencies 0.25, 0.5, 1, and 8 kHz only. The rise was more evident at the low than at the high frequencies. Temporary threshold shift (TTS) values were significantly less than those 8 years ago. Contrary to the previous TTS, the present TTS were higher at low than at high frequencies. Although progression of PTS at the frequencies 0.25 and 0.5 kHz was continuous throughout the observed durations of exposure, progression at higher frequencies occurred essentially in the first 10 to 15 years of exposure. Thereafter, it followed a much slower rate. Tinnitus was significantly associated with difficulty in hearing the human voice and with elevation of PTS at all the tested frequencies, while acoustic after-image was significantly associated with increment of PTS at the frequencies 0.25-2 kHz. No relation between PTS and smoking was found. PTS at low frequencies may provide an indication of progression of hearing damage when the sensitivity at 6 and 4 kHz diminishes after prolonged years of exposure. Tinnitus and acoustic after-image are related to the auditory effect of forge hammering noise.

  20. Population structure of Cicada barbara Stål (Hemiptera, Cicadoidea) from the Iberian Peninsula and Morocco based on mitochondrial DNA analysis.

    Science.gov (United States)

    Pinto-Juma, G A; Quartau, J A; Bruford, M W

    2008-02-01

    We assess the genetic history and population structure of Cicada barbara in Morocco and the Iberian Peninsula, based on analysis of the mitochondrial cytochrome b gene. The divergence between Morocco and the Iberian Peninsula populations was strongly corroborated by the molecular data, suggesting genetically isolated populations with a low level of gene flow. The Ceuta population from Spanish North Africa was more similar to the Iberian populations than the surrounding Moroccan populations, suggesting that the Strait of Gibraltar has not been acting as a strict barrier to dispersal while the Rif Mountains have. The Iberian Peninsula specimens showed a signature of demographic expansion before that which occurred in Morocco, but some of the assumptions related to the demographic parameters should be considered with caution due to the small genetic variation found. The high haplotype diversity found in Morocco implies higher demographic stability than in the Iberian Peninsula populations. These results do not, however, suggest a Moroccan origin for Iberian cicadas; but the most northwest region in Africa, such as Ceuta, might have acted as a southern refuge for Iberian cicadas during the most severe climatic conditions, from where they could expand north when climate improved. The separation of two subspecies within C. barbara (C. barbara lusitanica and C. barbara barbara) finds support with these results.

  1. Helium hammer in superfluid transfer

    Science.gov (United States)

    Tward, E.; Mason, P. V.

    1984-01-01

    Large transient pressure pulses, referred to as a helium hammer, which occurred in the transfer line of the main cryogenic tank during the development tests of the Infrared Astronomical Satellite, launched on January 25, 1983, are analyzed, and the measures taken to prevent a failure described. The modifications include an installation of a 2.3-liter surge tank upstream, and a back-up relief valve downstream, of a burst disk. The surge tank is designed to attenuate a 0.33-MPa pressure pulse at the inlet down to 0.092 MPa at the outlet. A mechanism of the pulse generation is suggested, which involves flashing and rapid recondensation of the small amount of liquid entering the warm section of a transition to room temperature.

  2. Computation of water hammer protection of modernized pumping station

    Science.gov (United States)

    Himr, Daniel

    2014-03-01

    Pumping station supplies water for irrigation. Maximal capacity 2 × 1.2m3·s-1 became insufficient, thus it was upgraded to 2 × 2m3·s-1. Paper is focused on design of protection against water hammer in case of sudden pumps trip. Numerical simulation of the most dangerous case (when pumps are giving the maximal flow rate) showed that existing air vessels were not able to protect the system and it would be necessary to add new vessels. Special care was paid to influence of their connection to the main pipeline, because the resistance of the connection has a significant impact on the scale of pressure pulsations. Finally, the pump trip was performed to verify if the system worked correctly. The test showed that pressure pulsations are lower (better) than computation predicted. This discrepancy was further analysed.

  3. Testing as a service with HammerCloud

    International Nuclear Information System (INIS)

    Llamas, Ramón Medrano; Barrand, Quentin; Sciabà, Andrea; Ster, Daniel van der; Elmsheuser, Johannes; Legger, Federica; Sciacca, Gianfranco

    2014-01-01

    HammerCloud was designed and born under the needs of the grid community to test the resources and automate operations from a user perspective. The recent developments in the IT space propose a shift to the software defined data centres, in which every layer of the infrastructure can be offered as a service. Testing and monitoring is an integral part of the development, validation and operations of big systems, like the grid. This area is not escaping the paradigm shift and we are starting to perceive as natural the Testing as a Service (TaaS) offerings, which allow testing any infrastructure service, such as the Infrastructure as a Service (IaaS) platforms being deployed in many grid sites, both from the functional and stressing perspectives. This work will review the recent developments in HammerCloud and its evolution to a TaaS conception, in particular its deployment on the Agile Infrastructure platform at CERN and the testing of many IaaS providers across Europe in the context of experiment requirements. The first section will review the architectural changes that a service running in the cloud needs, such an orchestration service or new storage requirements in order to provide functional and stress testing. The second section will review the first tests of infrastructure providers on the perspective of the challenges discovered from the architectural point of view. Finally, the third section will evaluate future requirements of scalability and features to increase testing productivity.

  4. A four-equation friction model for water hammer calculation in quasi-rigid pipelines

    International Nuclear Information System (INIS)

    Ghodhbani, Abdelaziz; Haj Taïeb, Ezzeddine

    2017-01-01

    Friction coupling affects water hammer evolution in pipelines according to the initial flow regime. Unsteady friction models are only validated with uncoupled formulation. On the other hand, coupled models such as four-equation model, provide more accurate prediction of water hammer since fluid-structure interaction (FSI) is taken into account, but they are limited to steady-state friction formulation. This paper deals with the creation of the “four-equation friction model” which is based on the incorporation of the unsteady head loss given by an unsteady friction model into the four-equation model. For transient laminar flow cases, the Zielke model is considered. The proposed model is applied to a quasi-rigid pipe with axial moving valve, and then calculated by the method of characteristics (MOC). Damping and shape of the numerical solution are in good agreement with experimental data. Thus, the proposed model can be incorporated into a new computer code. - Highlights: • Both Zielke model and four-equation model are insufficient to predict water hammer. • The four-equation friction model proposed is obtained by incorporating the unsteady head loss in the four-equation model. • The solution obtained by the proposed model is in good agreement with experimental data. • The wave-speed adjustment scheme is more efficient than interpolations schemes.

  5. Understanding IDEA 1997 and the 1999 Regulations with Barbara Bateman. [Videotape].

    Science.gov (United States)

    Council for Exceptional Children, Reston, VA. Div. for Learning Disabilities.

    The United States Congress amended the Individuals with Disabilities Education Act (IDEA) in 1997 to reflect changes in the special education field over the previous twenty years. In this 2-hour videotape recording designed for teachers, administrators, parents, and others, Dr. Barbara Bateman presents her insights about changes in IDEA law and…

  6. Female Athlete Triad/Relative Energy Deficiency in Sport: A Perspective Interview With Professor Barbara Drinkwater.

    Science.gov (United States)

    Carter, Susan

    2018-06-07

    Barbara Drinkwater has been a lifelong champion of equality for women in many areas of life well before it was widely accepted. Her "walking the walk" of women breaking barriers in traditional male roles in administration and leadership is exemplified by her election as the first woman president of the American College of Sports Medicine in 1988. Some of the controversial areas in which Barbara was vocal in the arena of women in sport, besides triad/relative energy deficiency in sport, include increased opportunity and participation, total equality, acceptance of diversity, intolerance of harassment and abuse, and fairness with transgender athletes. She co-founded the evidence-based advocacy group on the international stage known as Women Sport International. As a physiologist, Barbara has had a major influence on attention to the health of the female athlete, and she produced the original pioneering work in the field. Her impactful study, "Bone mineral density after resumption of menses in amenorrheic athletes," was published in the Journal of the American Medical Association in 1986. Since that time, the female athlete triad has set the stage for research and treatment to enhance women in physical activity at all levels.

  7. Numerical analysis of water hammer induced by injection of subcooled water into steam flow in a horizontal pipe

    International Nuclear Information System (INIS)

    Minato, Akihiko; Nagoyoshi, Takuji; Nakamura, Akira; Fujii, Yuzo; Aya, Izuo; Yamane, Kenji

    2004-01-01

    Subcooled water injection into steam flow in piping systems may generate a water column containing a large steam slug. The steam slug collapses due to rapid condensation and interfaces on both sides collides with each other. Water hammer takes place and sharp pressure pulse propagates through the pipe. The purpose of this study is to show capability of the present numerical simulation method for predictions of pressure transient and loads on a piping system following steam slug collapse. A three-dimensional computer code for transient gas-liquid two-phase flow was applied to simulate an experiment of steam-condensation-induced water hammer with a horizontal polycarbonate pipe. The code was based on the extended two-fluid model, which treated interface motion using the VOF (Volume of Fluid) technique. The Godunov scheme of highly compressible single-phase flow was modified for application to the Riemann problem solution of gas-liquid mixture. Analysis of local steam slug collapse resulted in comparable peak pressure and pulse width of pressure transients with the observation. The calculation of pressure pulse propagation and impact load on piping system showed the quasi-steady pressure load was imposed especially on elbow at 1/10 of water hammer peak pressure. (author)

  8. Quality assurance for hammer forgings

    International Nuclear Information System (INIS)

    Potthast, E.

    1984-01-01

    The quality assurance program introduced by Arbed Saarstahl and laid down in a quality assurance manual is described. A particular attention is attached thereby both to quality practice proper and to a reliable flow of information amongst all the persons involved. The production and test sequence schedules of the hammer forging plant are illustrated by the example of a forged valve housing for nuclear power plants. These schedules specify not only the forging process in the individual production stages but also the workpiece contour after each working operation, the heat treatment, the furnace charging, and the inspection of finished parts. The formalization of the tests is designed both to promote the customer's trust towards the supplier and to prevent the formal operations involved from hindering further technical development. (orig.) [de

  9. Water-hammer experiences in the startup and early operation of the Shearon Harris plant

    International Nuclear Information System (INIS)

    Casada, D.

    1987-01-01

    During the startup testing and initial operation of any power plant, systems undergo planned transients to confirm their ability to respond as designed. In addition to planned testing, unplanned transients infrequently occur as equipment is initially used. Some of both the planned and unplanned transients result in water-hammer events. Several water-hammer events experienced during preoperational testing, power ascension testing, and early operation of the Shearon Harris nuclear power plant are presented. The cause, effect, and corrective actions undertaken to prevent recurrence for each event discussed are provided. In addition, examples of preventive measures taken, based on industry experience accrued at other plants, to prevent a similar occurrence at Shearon Harris are discussed

  10. 77 FR 34991 - Notice of Inventory Completion: University of California, Santa Barbara, Repository of...

    Science.gov (United States)

    2012-06-12

    ...-46 was occupied in all of the major periods of local prehistory from the Oak Grove period (prior to... areas of Mescalitan Island were occupied throughout all periods of Santa Barbara prehistory, the human...

  11. Concrete density estimation by rebound hammer method

    International Nuclear Information System (INIS)

    Ismail, Mohamad Pauzi bin; Masenwat, Noor Azreen bin; Sani, Suhairy bin; Mohd, Shukri; Jefri, Muhamad Hafizie Bin; Abdullah, Mahadzir Bin; Isa, Nasharuddin bin; Mahmud, Mohamad Haniza bin

    2016-01-01

    Concrete is the most common and cheap material for radiation shielding. Compressive strength is the main parameter checked for determining concrete quality. However, for shielding purposes density is the parameter that needs to be considered. X- and -gamma radiations are effectively absorbed by a material with high atomic number and high density such as concrete. The high strength normally implies to higher density in concrete but this is not always true. This paper explains and discusses the correlation between rebound hammer testing and density for concrete containing hematite aggregates. A comparison is also made with normal concrete i.e. concrete containing crushed granite

  12. Koolitamine : andmisrõõm või edevus? / Ants Vasar, Arne Kaasik, Hele Hammer

    Index Scriptorium Estoniae

    Vasar, Ants

    2007-01-01

    Küsimusele, miks olete hakanud ettevõtjana koolitajaks, vastavad ASi Viru Keskus juhatuse liige Ants Vasar, Columbus IT Partner Eesti ASi pertner ja nõukogu esimees Arne Kaasik ja Amserv Grupi finantsdirektor Hele Hammer

  13. Anisotropy in Alpedrete granite cutting (Rift, Grain and Hardway directions) and effect on bush hammered heritage ashlars

    Science.gov (United States)

    Freire-Lista, David Martin; Fort, Rafael

    2015-04-01

    Many monuments and cities that are part of humanity's heritage have been built with carved granite ashlars. This dimension stone is one of the most used due to its abundance and durability. Traditional quarrymen have used anisotropic planes to cut granite blocks in the quarry for improved cutting performance. These planes are called Rift, Grain and Hardway (R, G, H) according to the ease of cutting. The aim of this study is to determine the response of each of the three orthogonal cutting planes R, G and H to the craft styling with bush hammer, based on their decay. Alpedrete granite was selected for this research, it is a monzogranite quarried in the Sierra de Guadarrana (Spanish Central System) foothills, in the province of Madrid, Spain. It is one of the most representative of Madrid's heritage granites. Alpedrete granite is also used as building stone in other European cities. From an Alpedrete granite bush hammered ashlar, three thin sections were cut parallel to the H plane; these thin sections cut R and G bush hammered planes. Also three thin sections have been cut parallel to the R plane at a distance of 2 mm, 10 mm and 30 mm from the bush hammered surface. All thin sections have been treated with fluorescein. In each of the thin sections a micrograph mosaic was performed covering the entire area (about 10 cm2, 300 photomicrographs) and printed with 120 increases. The length and spacing of inter-, intra- and trans-crystalline microcracks were quantified and measured. Microcracks were subdivided based on affected minerals in each R, G and H planes. Through these observations it was found that Alpedrete Granite R plane (easier to cut) is determined by exfoliation microcracks orientation. That is, R plane is parallel to the exfoliations microcracks, which are intra-crystalline and straight. The cutting of stones in the R plane is due to the coalescence of straight microcracks in the plane. This plane minimizes the effort and cost of subsequent carving so it

  14. Qualification of the new version of HAMMER computer code

    International Nuclear Information System (INIS)

    Chia, C.T.

    1984-06-01

    (HTEC) code were tested with a great number of diferent type of experiments. This experiments covers the most important parameters in neutronic calculations, such as the cell geometry and composition. The HTEC code results have been analysed and compared with experimental data and results given by the literature and simulated by HAMMER and LEOPARD codes. The quantities used for analysis were Keff and the following integral parameters: R28 - ratio of epicadmium-to-subcadmium 238 U captures; D25 - ratio of epicadmium-to-subcadmium 235 U fission; D28 - ratio of 238 U fissions to 235 U fissions; C - ratio of 238 U captures to 235 U fissions; RC02 - ratio of epicadmium-to-subcadmium 232 Th capture. The analysis shows that the results given by the code are in good agreement with the experimental data and the results given by the other codes. The calculation that have been done with the detailed ressonance profile tabulations of plutonium isotopes shows worst results than that obtained with the ressonance parameters. Almost all the simulated cases, shows that the HTEC results are closest to the experimental data than the HAMMER results, when one do not use the detailed ressonance profile tabulations of the plutonium isotopes. (Author) [pt

  15. Avoiding water hammer/fluid transients in nuclear piping systems by controlled filling

    International Nuclear Information System (INIS)

    1991-01-01

    A variety of geometries and operating procedures that lead to steam bubble collapse induced water hammers have been explored experimentally. Construction guidelines that will eliminate the problem at the design stage have been proposed and methods for predicting the pressure signatures proposed

  16. Some considerations on water-hammer and cavitation following the sudden closure of a check-valve

    International Nuclear Information System (INIS)

    Caumette, P.; Lott, M.

    1987-01-01

    The function of a no-return check-valve is to obturate a pipe when the current in it has a tendancy to revert: in normal operation the valve is maintained in open position by the flow and it closes, in case of flow-rate inversion, under the action of its own weight and of the hydrodynamic forces. At the precise time of closure, the stream most of the time is suddenly interrupted, which determines a water-hammer and the separation of a water column followed by other water-hammers. The authors analyze the movement of a swing check-valve before closure and the subsequent evolution of the fluid state

  17. Dynamic Brazilian Test of Rock Under Intermediate Strain Rate: Pendulum Hammer-Driven SHPB Test and Numerical Simulation

    Science.gov (United States)

    Zhu, W. C.; Niu, L. L.; Li, S. H.; Xu, Z. H.

    2015-09-01

    The tensile strength of rock subjected to dynamic loading constitutes many engineering applications such as rock drilling and blasting. The dynamic Brazilian test of rock specimens was conducted with the split Hopkinson pressure bar (SHPB) driven by pendulum hammer, in order to determine the indirect tensile strength of rock under an intermediate strain rate ranging from 5.2 to 12.9 s-1, which is achieved when the incident bar is impacted by pendulum hammer with different velocities. The incident wave excited by pendulum hammer is triangular in shape, featuring a long rising time, and it is considered to be helpful for achieving a constant strain rate in the rock specimen. The dynamic indirect tensile strength of rock increases with strain rate. Then, the numerical simulator RFPA-Dynamics, a well-recognized software for simulating the rock failure under dynamic loading, is validated by reproducing the Brazilian test of rock when the incident stress wave retrieved at the incident bar is input as the boundary condition, and then it is employed to study the Brazilian test of rock under the higher strain rate. Based on the numerical simulation, the strain-rate dependency of tensile strength and failure pattern of the Brazilian disc specimen under the intermediate strain rate are numerically simulated, and the associated failure mechanism is clarified. It is deemed that the material heterogeneity should be a reason for the strain-rate dependency of rock.

  18. If I Had a Hammer: Technology in the Language Arts Classroom.

    Science.gov (United States)

    Jester, Richard

    2002-01-01

    Describes the computer as a hammer, a tool with unique qualities that allows people to perceive, manipulate, and express language in ways quite different from traditional media. Explores the tool of the multimedia presentation, a common use of technology in classrooms today. Describes a simple project with sixth graders that incorporates reading,…

  19. A new approach for evaluating water hammer including the initial state of pressurization of the installation and fluid

    Directory of Open Access Journals (Sweden)

    G. Kaless

    2016-04-01

    Full Text Available The water hammer phenomenon is well known since the 19th century, while its mathematical formulation, by means of differential equations, is due to works of researchers such us Allievi (1903 and others from the beginning of the 20th century. The equations found in the technical publications produce a strange water hammer when the initial condition is defined assuming an incompressible fluid and a rigid pipe. The correct solution requires solving the water hammer equations for the initial state. When the finite difference method is applied, the initial state is solved by means of a set of non-linear equations. A novel approach is proposed including the initial state of pressurization into the governing equations and hence simplifying the calculus of the initial conditions. Furthermore, a critical reading of the deduction of the equations is done pointing out conceptual inconsistencies and proposing corrections.

  20. Conventional U-Pb dating versus SHRIMP of the Santa Barbara Granite Massif, Rondonia, Brazil

    Science.gov (United States)

    Sparrenberger, I.; Bettencourt, Jorge S.; Tosdal, R.M.; Wooden, J.L.

    2002-01-01

    The Santa Ba??rbara Granite Massif is part of the Younger Granites of Rondo??nia (998 - 974 Ma) and is included in the Rondo??nia Tin Province (SW Amazonian Craton). It comprises three highly fractionated metaluminous to peraluminous within-plate A-type granite units emplaced in older medium-grade metamorphic rocks. Sn-mineralization is closely associated with the late-stage unit. U-Pb monazite conventional dating of the early-stage Serra do Cicero facies and late-stage Serra Azul facies yielded ages of 993 ?? 5 Ma and 989 ?? 13 Ma, respectively. Conventional multigrain U-Pb isotope analyses of zircon demonstrate isotopic disturbance (discordance) and the preservation of inherited older zircons of several different ages and thus yield little about the ages of Sn-granite magmatism. SHRIMP U-Pb ages for the Santa Ba??rbara facies association yielded a 207Pb/206Pb weighted-mean age of 978 ?? 13 Ma. The textural complexity of the zircon crystals of the Santa Ba??rbara facies association, the variable concentrations of U, Th and Pb, as well as the mixed inheritance of zircon populations are major obstacles to using conventional multigrain U-Pb isotopic analyses. Sm-Nd model ages and ??Nd (T) values reveal anomalous isotopic data, attesting to the complex isotopic behaviour within these highly fractionated granites. Thus, SHRIMP U-Pb zircon and conventional U-Pb monazite dating methods are the most appropriate to constrain the crystallization age of the Sn-bearing granite systems in the Rondo??nia Tin Province.

  1. On culture and human development: Interview with Barbara Rogoff

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2011-01-01

    In this interview Professor Barbara Rogoff explores the many ways in which culture shapes the course of human development, and illustrates this with several findings from her past as well as most recent work. These reveal the vital importance of growing up in a family and a community for the human...... child and participating, from early on, in their various rituals and practices. Building on and enriching cultural psychological sources, Professor Rogoff offers us a comprehensive framework with which to understand both cultural and developmental phenomena and, above all, their multiple intersections...

  2. Water Hammer Mitigation on Postulated Pipe Break of Feed Water System

    International Nuclear Information System (INIS)

    Seong, Ho Je; Woo, Kab Koo; Cho, Keon Taek

    2008-01-01

    The Feed Water (FW) system supplies feedwater from the deaerator storage tank to the Steam Generators(S/G) at the required pressure, temperature, flow rate, and water chemistry. The part of FW system, from the S/G to Main Steam Valve House just outside the containment building wall, is designed as safety grade because of its safety function. According to design code the safety related system shall be designed to protect against dynamic effects that may results from a pipe break on high energy lines such as FW system. And the FW system should be designed to minimize blowdown volume of S/G secondary side during the postulated pipe break. Also the FW system should be designed to prevent the initiation or to minimize the effects of water hammer transients which may be induced by the pipe break. This paper shows the results of the hydrodynamic loads induced by the pipe break and the optimized design parameters to mitigate water hammer loads of FW system for Shin-Kori Nuclear Power Plant Unit 3 and 4 (SKN 3 and 4)

  3. Vertebrobasilar dolichoectasia induced hydrocephalus: the water-hammer effect

    Directory of Open Access Journals (Sweden)

    Vaso Zisimopoulou

    2015-05-01

    Full Text Available Vertebrobasilar dolichoectasia is a clinical entity associated rarely with obstructive hydrocephalus. We present a 48-year old male with a profound dilatation of the ventricular system due to a dolichoectatic basilar artery, as appeared in imaging studies. The patient suffered from longstanding hydrocephalus and presenile dementia. The underlying mechanism for obstructive hydrocephalus due to vertebrobasilar dolichoectasia is considered to be both a water-hammer effect and a direct compression of adjacent structures. We suggest prompt surgical intervention upon diagnosis as a first choice treatment in order to avoid further complications.

  4. Topografia vertebromedular de irara (Eira barbara Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Marta Adami

    2015-10-01

    Full Text Available Resumo: Um cadáver macho, adulto de irara (Eira barbara foi cedido pelo Centro de Triagem de Animais Silvestres (Cetas, localizado em Salvador/Bahia, ao Setor de Anatomia Veterinária da Escola de Medicina Veterinária e Zootecnia da Universidade Federal da Bahia. Trata-se de um mamífero carnívoro que pertence à Família Mustelidae e Subfamília Mustelinae que contém o Gênero Eira, representado apenas pela Espécie Eira barbara. Objetivamos a investigação da topografia vertebromedular do espécime e assim verificar a relação da medula espinal com o canal vertebral; a identificação, origem, emergência e quantificação dos nervos espinhais relacionados com a medula espinal. Pesquisa número 43245-1 autorizada pelo Sistema de Autorização e Informação em Biodiversidade (Sisbio-ICMBio/IBAMA. O exemplar foi fixado em solução de formaldeído a 10% e posteriormente dissecado e radiografado. Foram identificados oito pares de nervos espinhais cervicais, quatorze torácicos e na porção lombossacral da medula espinhal seis nervos espinais lombares, três sacrais e mais de três nervos espinhais caudais. O término da medula espinal ocorreu no nível quinta vértebra lombar. Os oito segmentos medulares cervicais localizaram-se entre a primeira e sétima vértebras cervicais. Os quatorze nervos espinais torácicos originaram-se na porção cranial das vértebras respectivas. Os segmentos medulares lombares, sacrais e caudais restringiram-se à região lombar da coluna vertebral. O deslocamento cranial dos segmentos medulares foi observado no oitavo cervical, terceiro, quarto e quinto lombares e todos os segmentos sacrais e caudais. As informações obtidas poderão ser utilizadas para análises comparativas com as demais espécies e com a adoção de medidas que visem proporcionar o bem-estar animal e a preservação da espécie.

  5. Assessment of water hammer effects on boiling water nuclear reactor core dynamics

    Directory of Open Access Journals (Sweden)

    Bousbia-Salah Anis

    2007-01-01

    Full Text Available Complex phenomena, as water hammer transients, occurring in nuclear power plants are still not very well investigated by the current best estimate computational tools. Within this frame work, a rapid positive reactivity addition into the core generated by a water hammer transient is considered. The numerical simulation of such phenomena was carried out using the coupled RELAP5/PARCS code. An over all data comparison shows good agreement between the calculated and measured core pressure wave trends. However, the predicted power response during the excursion phase did not correctly match the experimental tendency. Because of this, sensitivity studies have been carried out in order to identify the most influential parameters that govern the dynamics of the power excursion. After investigating the pressure wave amplitude and the void feed back responses, it was found that the disagreement between the calculated and measured data occurs mainly due to the RELAP5 low void condensation rate which seems to be questionable during rapid transients. .

  6. The effect of cryogenic grinding and hammer milling on the flavour quality of ground pepper (Piper nigrum L.).

    Science.gov (United States)

    Liu, Hong; Zeng, Fankui; Wang, Qinghuang; Ou, Shiyi; Tan, Lehe; Gu, Fenglin

    2013-12-15

    In this study, we compared the effects of cryogenic grinding and hammer milling on the flavour attributes of black, white, and green pepper. The flavour attributes were analysed using headspace solid-phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS), sensory evaluation and electronic nose (e-nose) analysis. Cryogenic grinding resulted in minimal damage to the colour, flavour, and sensory attributes of the spices. Cryogenic grinding was also better than hammer milling at preserving the main potent aroma constituents, but the concentrations of the main aroma constituents were dramatically reduced after storing the samples at 4 °C for 6 months. Pattern matching performed by the e-nose further supported our sensory and instrumental findings. Overall, cryogenic grinding was superior to hammer milling for preserving the sensory properties and flavour attributes of pepper without significantly affecting its quality. However, we found that the flavour quality of ground pepper was reduced during storage. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Water hammer experiences in the startup and early operation of the Shearon Harris plant

    International Nuclear Information System (INIS)

    Casada, D.A.

    1987-01-01

    During the course of preoperational testing and early operation of the Shearon Harris Nuclear Power Plant, several water hammer events have occurred. A description of the events and corrective/preventive measures taken are discussed

  8. Experimental evaluation of ability of Relap5, Drako, Flowmaster2TM and program using unsteady wall friction model to calculate water hammer loadings on pipelines

    International Nuclear Information System (INIS)

    Marcinkiewicz, Jerzy; Adamowski, Adam; Lewandowski, Mariusz

    2008-01-01

    Mechanical loadings on pipe systems caused by water hammer (hydraulic transients) belong to the most important and most difficult to calculate design loadings in nuclear power plants. The most common procedure in Sweden is to calculate the water hammer loadings on pipe segments, according to the classical one-dimensional (1D) theory of liquid transient flow in a pipeline, and then transfer the results to strength analyses of pipeline structure. This procedure assumes that there is quasi-steady respond of the pipeline structure to pressure surges-no dynamic interaction between the fluid and the pipeline construction. The hydraulic loadings are calculated with 1D so-called 'network' programs. Commonly used in Sweden are Relap5, Drako and Flowmaster2-all using quasi-steady wall friction model. As a third party accredited inspection body Inspecta Nuclear AB reviews calculations of water hammer loadings. The presented work shall be seen as an attempt to illustrate ability of Relap5, Flowmaster2 and Drako programs to calculate the water hammer loadings. A special attention was paid to using of Relap5 for calculation of water hammer pressure surges and forces (including some aspects of influence of Courant number on the calculation results) and also the importance of considering the dynamic (or unsteady) friction models. The calculations are compared with experimental results. The experiments have been conducted at a test rig designed and constructed at the Szewalski Institute of Fluid Flow Machinery of the Polish Academy of Sciences (IMP PAN) in Gdansk, Poland. The analyses show quite small differences between pressures and forces calculated with Relap5, Flowmaster2 and Drako (the differences regard mainly damping of pressure waves). The comparison of calculated and measured pressures and also a force acting on a pre-defined pipe segment shows significant differences. It is shown that the differences can be reduced by using unsteady friction models in calculations

  9. Groundwater-quality data in the Santa Barbara study unit, 2011: results from the California GAMA Program

    Science.gov (United States)

    Davis, Tracy A.; Kulongoski, Justin T.; Belitz, Kenneth

    2013-01-01

    CDPH. Comparisons between data collected for this study and benchmarks for drinking water are for illustrative purposes only and are not indicative of compliance or non-compliance with those benchmarks. All organic constituents and most inorganic constituents that were detected in groundwater samples from the 18 grid wells in the Santa Barbara study unit were detected at concentrations less than drinking-water benchmarks. Of the 220 organic and special-interest constituents sampled for at the 18 grid wells, 13 were detected in groundwater samples; concentrations of all detected constituents were less than regulatory and non-regulatory health-based benchmarks. In total, VOCs were detected in 61 percent of the 18 grid wells sampled, pesticides and pesticide degradates were detected in 11 percent, and perchlorate was detected in 67 percent. Polar pesticides and their degradates, pharmaceutical compounds, and NDMA were not detected in any of the grid wells sampled in the Santa Barbara study unit. Eighteen grid wells were sampled for trace elements, major and minor ions, nutrients, and radioactive constituents; most detected concentrations were less than health-based benchmarks. Exceptions are one detection of boron greater than the CDPH notification level (NL-CA) of 1,000 micrograms per liter (μg/L) and one detection of fluoride greater than the CDPH maximum contaminant level (MCL-CA) of 2 milligrams per liter (mg/L). Results for constituents with non-regulatory benchmarks set for aesthetic concerns from the grid wells showed that iron concentrations greater than the CDPH secondary maximum contaminant level (SMCL-CA) of 300 μg/L were detected in three grid wells. Manganese concentrations greater than the SMCL-CA of 50 μg/L were detected in seven grid wells. Chloride was detected at a concentration greater than the SMCL-CA recommended benchmark of 250 mg/L in four grid wells. Sulfate concentrations greater than the SMCL-CA recommended benchmark of 250 mg/L were measured

  10. Stable sonoluminescence within a water hammer tube.

    Science.gov (United States)

    Chakravarty, Avik; Georghiou, Theo; Phillipson, Tacye E; Walton, Alan J

    2004-06-01

    The sonoluminescence (SL) from the collapse of a single gas bubble within a liquid can be produced repetitively using an acoustic resonator. An alternative technique using a water hammer tube, producing SL from bubbles of greater size, is described here. A sealed vertical tube partly filled with a liquid and a gas at low pressure is subjected to vertical vibrations. The oscillation of the pressure within the liquid column, due to inertial forces, excites cavitation bubbles to grow and collapse. Rotation is used to confine the bubbles to the axis of the tube. Bright SL emissions were observed in a number of liquids. Repetitive emission was produced from bubbles in condensed phosphoric acid. Bubbles of 0.4 mm ambient radius (containing 2x 10(14) xenon atoms) were excited by vibration at 35 Hz. Approximately 10(12) photons were emitted per collapse in the range 400-700 nm (over four orders of magnitude greater than the brightest SL reported previously), corresponding to a 1% efficiency of the conversion of mechanical energy into light.

  11. Psi Chi/APA Edwin B. Newman Graduate Research Award: Joseph H. Hammer

    Science.gov (United States)

    American Psychologist, 2009

    2009-01-01

    Joseph H. Hammer, recipient of the Psi Chi/APA Edwin B. Newman Graduate Research Award, is cited for an outstanding research paper whose findings provide important evidence regarding the promise of a male-sensitive approach to mental health marketing and empirically support the inclusion of theory-driven enhancements in group-targeted mental…

  12. Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill

    Science.gov (United States)

    Sherrit, Stewart (Inventor); Bao, Xiaoqi (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor)

    2014-01-01

    A Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill includes a horn actuator having high power piezoelectric materials and a flexure pre-stress to increase the actuators effectiveness. The drill is a low mass, low power, compact coring drill measuring 20-cm high by 7-cm diameter and having a total weight of 2 kg including drive electronics. Using an average power of 50-Watts, the drill basalt is expected to cut basalt at a rate of 0.2 cm/min down to depth of 10-cm and create cuttings and an intact core. The drill is expected to operate under different environments including Martian ambient (6 Torr and down to -50 degree C), and liquid nitrogen temperatures (77 K) and low pressure (<<1 Torr) to simulate lunar polar and Europa conditions. Materials expected to be sampled include Kaolinite, Saddleback Basalt, Limestone, Volcanic Breccia, Siltstone, ice, permafrost and layered rocks with different hardness.

  13. Modern Modeling of Water Hammer

    Directory of Open Access Journals (Sweden)

    Urbanowicz Kamil

    2017-09-01

    Full Text Available Hydraulic equipment on board ships is common. It assists in the work of: steering gear, pitch propellers, watertight doors, cargo hatch covers, cargo and mooring winches, deck cranes, stern ramps etc. The damage caused by transient flows (which include among others water hammer are often impossible to repair at sea. Hence, it is very important to estimate the correct pressure runs and associated side effects during their design. The presented study compares the results of research on the impact of a simplified way of modeling the hydraulic resistance and simplified effective weighting functions build of two and three-terms on the estimated results of the pressure changes. As it turns out, simple effective two-terms weighting functions are able to accurately model the analyzed transients. The implementation of the presented method will soon allow current automatic protection of hydraulic systems of the adverse effects associated with frequent elevated and reduced pressures.

  14. Condensation induced water hammer in steam generators

    International Nuclear Information System (INIS)

    Jones, O.C. Jr.; Saha, P.; Wu, B.J.C.; Ginsberg, T.

    1979-06-01

    The case of condensation induced water hammer in nuclear steam generators is summarized, including both feed ring-type and economizer-type geometries. A slug impact model is described and used to demonstrate the parametric dependence of the impact pressures on heat transfer rates, initial pressures, and relative initial slug and void lengths. The results of the parametric study are related also to the economizer geometry and a suggested alternative model is presented. The importance of concerns regarding attenuation of shocks in two-phase media is delineated, and a simple experiment is described which was used to determine negligible attenuation within the accuracy of the experiment for void fractions up to over 30% in bubbly and slug flows

  15. HAMMER: Reweighting tool for simulated data samples

    CERN Document Server

    Duell, Stephan; Ligeti, Zoltan; Papucci, Michele; Robinson, Dean

    2016-01-01

    Modern flavour physics experiments, such as Belle II or LHCb, require large samples of generated Monte Carlo events. Monte Carlo events often are processed in a sophisticated chain that includes a simulation of the detector response. The generation and reconstruction of large samples is resource-intensive and in principle would need to be repeated if e.g. parameters responsible for the underlying models change due to new measurements or new insights. To avoid having to regenerate large samples, we work on a tool, The Helicity Amplitude Module for Matrix Element Reweighting (HAMMER), which allows one to easily reweight existing events in the context of semileptonic b → q ` ̄ ν ` analyses to new model parameters or new physics scenarios.

  16. Mineralogical characterization of the argillaceous material from the Municipality of Santa Barbara, Para, Brazil; Caracterizacao mineralogica de material argiloso proveniente do municipio de Santa Barbara, Para, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrando, E.A., E-mail: edemarino@ufpa.b [Universidade Federal do Para (UFPA), Maraba, PA (Brazil). Fac. de Engenharia de Materiais. Lab. de Materiais Ceramicos; Sheller, T.; Angelica, R.S. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Fac. de Geologia. Inst. de Geociencias; Neves, R.S. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Fac. de Engenharia Quimica. Inst. de Tecnologia

    2009-07-01

    In the present work were investigated mineralogical phases in a material with argillaceous characteristic of the region of Genipauba, Santa Barbara, State of Para. Characterization of the collected sample was performed by X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG) and infrared spectroscopy (IR). The results of the assays indicate the presence of the clay minerals like kaolinite and muscovite, as well as minerals as quartz and anatase. (author)

  17. Study on the Effect of the Impact Location and the Type of Hammer Tip on the Frequency Response Function (FRF) in Experimental Modal Analysis of Rectangular Plates

    Science.gov (United States)

    Mali, K. D.; Singru, P. M.

    2018-03-01

    In this work effect of the impact location and the type of hammer tip on the frequency response function (FRF) is studied. Experimental modal analysis of rectangular plates is carried out for this purpose by using impact hammer, accelerometer and fast Fourier transform (FFT) analyzer. It is observed that the impulse hammer hit location has, no effect on the eigenfrequency, yet a difference in amplitude of the eigenfrequencies is obtained. The effect of the hammer tip on the pulse and the force spectrum is studied for three types of tips metal, plastic and rubber. A solid rectangular plate was excited by using these tips one by one in three different tests. It is observed that for present experimental set up plastic tip excites the useful frequency range.

  18. Generation and tests of the new version 88 library for HAMMER system

    International Nuclear Information System (INIS)

    Chalhoub, E.S.; Anaf, J.

    1988-08-01

    A new library, version 88, for the HAMMER system, was generated using the ENDF/B-IV FRENDL evaluated nuclear data libraries. It is composed of epithermal and thermal libraries obtained by processing the new versions of ETOG-3 and FLANGE-II codes, respectively. Test results for two benchmark critical assemblies are presented. (author) [pt

  19. Learning to Control Orientation and Force in a Hammering Task The Initial Stage

    NARCIS (Netherlands)

    Vernooij, Carlijn A.; Mouton, Leonora J.; Bongers, Raoul M.

    2012-01-01

    The ability to create stone tools is considered an important step in the emergence of human cognition. To further our understanding of these evolutionary processes we focused on the initial learning processes with which this percussive skill may be acquired. We studied a hammering task in which

  20. Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

    CERN Document Server

    Van der Ster , D; Medrano Llamas, R; Legger , F; Sciaba, A; Sciacca, G; Ubeda Garca , M

    2012-01-01

    Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion p...

  1. Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion ...

  2. Experimental and numerical analysis of water hammer in a large-scale PVC pipeline apparatus

    NARCIS (Netherlands)

    Bergant, A.; Hou, Q.; Keramat, A.; Tijsseling, A.S.; Gajic, A.; Benisek, M.; Nedeljkovic, M.

    2011-01-01

    This paper investigates the effects of the pipe-wall viscoelasticity on water-hammer pressures. A large-scale pipeline apparatus made of polyvinyl chloride (PVC) at Deltares, Delft, The Netherlands, has been used to carry out waterhammer experiments. Tests have been conducted in a

  3. Analysis of water hammer-structure interaction in piping system for a loss of coolant accident in primary loop of pressurized water reactor

    International Nuclear Information System (INIS)

    Zhang Xiwen; Yang Jinglong; He Feng; Wang Xuefang

    2000-01-01

    The conventional analysis of water hammer and dynamics response of structure in piping system is divided into two parts, and the interaction between them is neglected. The mechanism of fluid-structure interaction under the double-end break pipe in piping system is analyzed. Using the characteristics method, the numerical simulation of water hammer-structure interaction in piping system is completed based on 14 parameters and 14 partial differential equations of fluid-piping cell. The calculated results for a loss of coolant accident (LOCA) in primary loop of pressurized water reactor show that the waveform and values of pressure and force with time in piping system are different from that of non-interaction between water hammer and structure in piping system, and the former is less than the later

  4. The Effect of Venue and Wind on the Distance of a Hammer Throw

    Science.gov (United States)

    Hunter, Iain

    2005-01-01

    In track and field, gravity and air resistance act on the hammer after it has been released. Both of these forces depend on altitude and latitude. In addition, air resistance also depends on wind, temperature, humidity, and barometric pressure. Often, air resistance and varying gravity throughout the earth are not considered when throwing…

  5. Water hammer with column separation : a review of research in the twentieth century

    NARCIS (Netherlands)

    Bergant, A.; Simpson, A.R.; Tijsseling, A.S.

    2004-01-01

    Column separation refers to the breaking of liquid columns in fully filled pipelines. This may occur in a water hammer event when the pressure drops to the vapor pressure at specific locations such as closed ends, high points or knees (changes in pipe slope). A vapor cavity, driven by the inertia of

  6. Intensive Cultural Resources Survey for the Goleta Flood Protection Program, Santa Barbara County, California.

    Science.gov (United States)

    1982-04-01

    years old or greater, " adultos ". The percentage of people eventually baptized from the Goleta towns who were living in 1782 was 56.5%, if the midpoint... Mayor of Santa Barbara called the Slough "One of the area’s greatest economic assets, given its tourist potential, if properly developed (SBNP April

  7. Evaluasi Unjuk Kerja Sistem Proteksi Water Hammer pada Sistem Perpipaan (Studi Kasus Di Rumah Pompa Produksi Unit Instalasi Pengolahan Air Minum (IPAM Karang Pilang 2 PT. PDAM Surya Sembada Surabaya

    Directory of Open Access Journals (Sweden)

    Handi Prasetya

    2017-01-01

    Full Text Available Sistem jaringan perpipaan merupakan komponen penting dalam menunjang produksi maupun distribusi pada sektor industri. Jaringan perpipaan mengalami beberapa fenomena seperti distribusi fluida dan water hammer. Water hammer sering terjadi di daerah discharge pompa pada saat pengoperasian pompa maupun pada saat kegagalan operasi pompa. Beberapa cara untuk mengurangi dampak water hammer adalah dengan menambahkan flywheel ataupun gas accumulator pada jaringan perpipaan. Lonjakan tekanan serta aliran balik yang terjadi akibat fenomena water hammer akan dilawan oleh putaran impeller  pompa yang dibebani oleh flywheel dan akan memperlambat lonjakan tekanan dalam pipa dan tekanan yang berlebih akan dibuang ke gas accumulator sehingga tekanan dalam pipa berangsur stabil. Pemodelan sistem perpipaan dilakukan dengan menggunakan software sistem perpipaan. Pemodelan yang disimulasikan merupakan sistem perpipaan dengan rangkaian pompa paralel yang dilengkapi flywheel pada instalasi pompa dan divariasikan dengan penambahan gas accumulator sebagai sistem proteksi water hammer. Analisa yang dilakukan adalah untuk mempelajari fenomena water hammer pada saat kondisi ekstrim yakni ketika dua pompa operasi mati dan juga ketika empat pompa operasi mati, untuk melihat pengaruh variasi ukuran flywheel terhadap fluktuasi tekanan yang terjadi. Ukuran flywheel divariasikan yakni ukuran diameter luar 1100mm, 1200mm dan 1300mm dengan tebal masing-masing 300mm, 400mm dan 500mm. Hasil simulasi menunjukkan bahwa pada sistem perpipaan tanpa menggunakan gas accumulator, tekanan maksimum yang terjadi pada discharge pompa mencapai 19,807 bar dari kondisi tekanan kerjanya 5,6 bar. Variasi ukuran flywheel memberi dampak pada perlambatan terjadinya lonjakan tekanan, semakin besar ukuran flywheel akan menunda terjadinya lonjakan tekanan akibat water hammer. Dan penambahan gas accumulator berperan dalam meredam serta mempersingkat waktu terjadinya lonjakan tekanan, sehingga fluktuasi

  8. Application of perturbation methods and sensitivity analysis to water hammer problems in hydraulic networks

    International Nuclear Information System (INIS)

    Balino, Jorge L.; Larreteguy, Axel E.; Andrade Lima, Fernando R.

    1995-01-01

    The differential method was applied to the sensitivity analysis for water hammer problems in hydraulic networks. Starting from the classical water hammer equations in a single-phase liquid with friction, the state vector comprising the piezometric head and the velocity was defined. Applying the differential method the adjoint operator, the adjoint equations with the general form of their boundary conditions, and the general form of the bilinear concomitant were calculated. The discretized adjoint equations and the corresponding boundary conditions were programmed and solved by using the so called method of characteristics. As an example, a constant-level tank connected through a pipe to a valve discharging to atmosphere was considered. The bilinear concomitant was calculated for this particular case. The corresponding sensitivity coefficients due to the variation of different parameters by using both the differential method and the response surface generated by the computer code WHAT were also calculated. The results obtained with these methods show excellent agreement. (author). 11 refs, 2 figs, 2 tabs

  9. Research on the water hammer protection of the long distance water supply project with the combined action of the air vessel and over-pressure relief valve

    International Nuclear Information System (INIS)

    Li, D D; Jiang, J; Zhao, Z; Yi, W S; Lan, G

    2013-01-01

    We take a concrete pumping station as an example in this paper. Through the calculation of water hammer protection with a specific pumping station water supply project, and the analysis of the principle, mathematical models and boundary conditions of air vessel and over-pressure relief valve we show that the air vessel can protect the water conveyance system and reduce the transient pressure damage due to various causes. Over-pressure relief valve can effectively reduce the water hammer because the water column re-bridge suddenly stops the pump and prevents pipeline burst. The paper indicates that the combination set of air vessel and over-pressure relief valve can greatly reduce the quantity of the air valve and can eliminate the water hammer phenomenon in the pipeline system due to the vaporization and water column separation and re-bridge. The conclusion could provide a reference for the water hammer protection of long-distance water supply system

  10. Research on the water hammer protection of the long distance water supply project with the combined action of the air vessel and over-pressure relief valve

    Science.gov (United States)

    Li, D. D.; Jiang, J.; Zhao, Z.; Yi, W. S.; Lan, G.

    2013-12-01

    We take a concrete pumping station as an example in this paper. Through the calculation of water hammer protection with a specific pumping station water supply project, and the analysis of the principle, mathematical models and boundary conditions of air vessel and over-pressure relief valve we show that the air vessel can protect the water conveyance system and reduce the transient pressure damage due to various causes. Over-pressure relief valve can effectively reduce the water hammer because the water column re-bridge suddenly stops the pump and prevents pipeline burst. The paper indicates that the combination set of air vessel and over-pressure relief valve can greatly reduce the quantity of the air valve and can eliminate the water hammer phenomenon in the pipeline system due to the vaporization and water column separation and re-bridge. The conclusion could provide a reference for the water hammer protection of long-distance water supply system.

  11. Monitoring the content of fluorine, lead and cadmium in water for human consumption in a sector of Santa Barbara of Heredia

    International Nuclear Information System (INIS)

    Arias Sanchez, Federico; Alvarado, A.L.

    2000-01-01

    Samples of drinking water from natural sources and distribution tanks in a specific area of Santa Barbara of Heredia were analyzed. The content of fluorine, lead and cadmium was determined applying the Spans method and Anodic Stripping Voltamperometry respectively, over a period of nine months. During July 1994 to February 1995, levels of lead, cadmium and fluoride in the samples, remained under the permissible limits according to the Norma Nacional para la Calidad del Agua Potable, and therefore do not represent a toxicological danger to the population of Santa Barbara of Heredia. (author) [es

  12. Condensation induced water hammer (CIWH). Relevance in the nuclear industry and state of science and technology

    Energy Technology Data Exchange (ETDEWEB)

    Swidersky, Harald [TUeV Sued Industrie Service GmbH, Muenchen (Germany)

    2013-03-15

    Condensation-induced water hammers (CIWH) are consequences of rapid condensation of steam in partially filled pipes. They present a particular hazard potential, as they seem to occur spontaneously and out of stagnation. The entire process still eludes a secured analytical or numerical predictability and determination of the fluid dynamic loads. The simulation of these processes is one of the most difficult tasks of thermal hydraulic transient analyses. Condensation induced water hammers in plants - mostly power plants - can lead to significant costs if they result in long downtimes, detailed analyses and upgrades. In this contribution, the phenomenon CIWH is explained and the relevance for nuclear engineering will be discussed. An outlook on the actual requirements of regulatory guidelines and the state of science and technology will be given. (orig.)

  13. Condensation induced water hammer (CIWH). Relevance in the nuclear industry and state of science and technology

    International Nuclear Information System (INIS)

    Swidersky, Harald

    2013-01-01

    Condensation-induced water hammers (CIWH) are consequences of rapid condensation of steam in partially filled pipes. They present a particular hazard potential, as they seem to occur spontaneously and out of stagnation. The entire process still eludes a secured analytical or numerical predictability and determination of the fluid dynamic loads. The simulation of these processes is one of the most difficult tasks of thermal hydraulic transient analyses. Condensation induced water hammers in plants - mostly power plants - can lead to significant costs if they result in long downtimes, detailed analyses and upgrades. In this contribution, the phenomenon CIWH is explained and the relevance for nuclear engineering will be discussed. An outlook on the actual requirements of regulatory guidelines and the state of science and technology will be given. (orig.)

  14. The impacts of hammer-mill screen size and grain particle size on the performance of broiler chickens offered diets based on two red sorghum varieties.

    Science.gov (United States)

    Selle, P H; Truong, H H; Khoddami, A; Moss, A F; Roberts, T H; Liu, S Y

    2016-12-12

    1. The two red grain sorghums were extensively characterised. Kafirin, polyphenolic compounds, free, conjugated and bound phenolic acids, phytate concentrations and starch pasting profiles were determined. 2. The experiment consisted of a 2 × 4 factorial array of dietary treatments comprising two red sorghum varieties (Tiger and Block I) ground through 4 hammer-mill screen sizes (2.0, 3.2, 4.8 6.0 mm) prior to incorporation into nutritionally equivalent diets. Eight steam-pelleted dietary treatments were each offered to 7 replicates (6 male Ross 308 birds per cage) from 7 to 28 d post-hatch. 3. Effects of dietary treatments on growth performance, relative gizzard and pancreas weights, nutrient utilisation, apparent starch and protein (N) digestibility coefficients and disappearance rates from 4 small intestinal segments were determined. 4. The 2.0-mm hammer-mill screen generated an average geometric mean particle size of 794 μm and the 6.0-mm screen a mean particle size of 1405 μm. However, hammer-mill screen size did not influence weight gain or FCR. The 6.0-mm screen size generated significantly higher starch and protein (N) digestibility coefficients in the distal jejunum and distal ileum than the 2.0-mm hammer-mill screen. 5. Tiger sorghum was superior to Block I sorghum, as significant advantages were observed for feed conversion ratios (3.25%), AME (0.37 MJ), ME:GE ratios (4.15%), AMEn (0.53 MJ), distal ileal starch digestibility coefficients (2.46%) and protein (N) digestibility coefficients in the distal jejunum (4.66%), proximal ileum (1.96%) and distal ileum (2.16%). The inferior Block I sorghum contained more kafirin (67.1 versus 51.3 g/kg), phytate (9.79 versus 8.40 g/kg), total phenolic compounds (4.68 versus 4.12 mg GAE/g), flavan-4-ols (7.98 versus 5.04 ABS/ml/g), total phenolic acids (554 versus 402 μg/g) and total ferulic acid (375 versus 281 μg/g) in comparison to Tiger sorghum.

  15. Evaluation of Reductive Option of Water Hammer Phenomenon for a Water Conveyance System, A Case Study of Shahid Shirdom Residential District-Tehran

    Directory of Open Access Journals (Sweden)

    Kiyomars roshangar

    2015-01-01

    Full Text Available Sudden changes in the boundary conditions of water transmission systems, such as sudden opening and closing of valves or abrupt on and off switching of pumps and turbines cause a transient flow called ‘water hammer’. In this study, comparisons were made between the effective parameters including pipeline material, on the one hand, and the equipment and tools available for reducing the effects of water hammer, on the other. For this purpose, a practical example of a water transmission line from a pumping station located near Shahid Shirdom Residential District to the upstream reservoir in Tehran was used for modeling by the Bentley Hammer XMV: 8 software. The results obtained for the different parameters and options were compared and it was revealed that, regarding the pipe material, GRP pipes reduced pressure by 49.1 Kpa compared to the Asbestos cement pipes and by 50.3 Kpa compared to the iron pipes. Comparison of the results for the protective systems indicated that the surge tank outperformed the other alternatives in controlling pressure such that maximum pressure was reduced by 3.9 bar when using surge tanks compared to the flywheel and by 5 bar compared to the check valve. Finally, it was found that the concurrent use of the surge tank and the flywheel would be the most ideal method for controlling the water hammer effects.

  16. STUDY OF WATER HAMMERS IN THE FILLING OF THE SYSTEM OF PRESSURE COMPENSATION IN THE WATER-COOLED AND WATER-MODERATED POWER REACTORS

    Directory of Open Access Journals (Sweden)

    A. V. Korolyev

    2017-01-01

    Full Text Available The research presented in the article conforms to the severe accident that took place at the Three Mail Island nuclear power plant in the USA. The research is focused on improving the reliability of the pressure compensator that is an important equipment of the primary circuit. In order to simulate such a situation, the stand has been developed to simulate the design of the pressurizer of the PWR-440 reactor, in particular an elliptical shape of the upper lid which has a steam outlet pipe at the top of the construction that creates conditions for occurrence of such water hammers. For the experiments, an installation has been created that makes it possible to measure and record the water hammering that occur when the tanks are filled. Measurement of the amplitude of the water hammering was carried out by a specially developed piezoelectric sensor, and the registration – by a light-beam oscilloscope. The technique of carrying out the experiment is described and the results of an experimental study of the water hammers arising when the vessels are completely filled are presented. Quantitative data were obtained on the amplitudes of the hydraulic impacts depending on the rate of filling of the vessel and the diameter of the outlet, the maximum pressure of the hydraulic shock was 7–9 atm. Comparison of calculated and experimental data has been performed. The allowable discrepancy is explained by the calculated value of the system stiffness coefficient, which did not take into account the presence of welded seams in the tank that imparts the system with additional rigidity. The calculated relationships are obtained, that make it possible to estimate the amplitudes of the water hammers through the acceleration of the water level in front of the outlet from a vessel with an elliptical bottom. The possibility of a water hammer in the pressure compensator is demonstrated by experiment and by theoretical calculations. Based on the experimental data, a

  17. Water-hammer in the feed-water pipes for PWR steam generators

    International Nuclear Information System (INIS)

    Gonnet, Bernard; Leroy, Claude; Oullion, Jean; Yazidjian, J.-C.

    1979-01-01

    PWR boiler water feed pipes have been known for several years to be affected by violent water-hammer during start-ups and operation of the plant. In view of the varying results of corrective design modifications in America and Europe, FRAMATOME undertook an experimental research programme which resulted in the adoption of cruciform tubes on the feed-water distributor as the most reliable solution. Subsequent tests at Fessenheim I confirmed the effectiveness of this device [fr

  18. Robust Sub-harmonic Mixer at 340 GHz Using Intrinsic Resonances of Hammer-Head Filter and Improved Diode Model

    Science.gov (United States)

    Wang, Cheng; He, Yue; Lu, Bin; Jiang, Jun; Miao, Li; Deng, Xian-Jin; Xiong, Yong-zhong; Zhang, Jian

    2017-11-01

    This paper presents a sub-harmonic mixer at 340 GHz based on anti-parallel Schottky diodes (SBDs). Intrinsic resonances in low-pass hammer-head filter have been adopted to enhance the isolation for different harmonic components, while greatly minimizing the transmission loss. The application of new DC grounding structure, impedance matching structure, and suspended micro-strip mitigates the negative influences of fabrication errors from metal cavity, quartz substrate, and micro-assembly. An improved lumped element equivalent circuit model of SBDs guarantees the accuracy of simulation, which takes current-voltage (I/V) behavior, capacitance-voltage (C/V) behavior, carrier velocity saturation, DC series resistor, plasma resonance, skin effect, and four kinds of noise generation mechanisms into consideration thoroughly. The measurement indicates that with local oscillating signal of 2 mW, the lowest double sideband conversion loss is 5.5 dB at 339 GHz; the corresponding DSB noise temperature is 757 K. The 3 dB bandwidth of conversion loss is 50 GHz from 317 to 367 GHz.

  19. Blue oak plant communities of southern San Luis Obispo and northern Santa Barbara Counties, California

    Science.gov (United States)

    Mark I. Borchert; Nancy D. Cunha; Patricia C. Krosse; Marcee L. Lawrence

    1993-01-01

    An ecological classification system has been developed for the Pacific Southwest Region of the Forest Service. As part of that classification effort, blue oak (Quercus douglasii) woodlands and forests of southern San Luis Obispo and northern Santa Barbara Counties in Los Padres National Forest were classified into I3 plant communities using...

  20. Comparison between UMSICHT water hammer experiments and calculations using RELAP5/MOD3.3

    International Nuclear Information System (INIS)

    Messing, Ralf

    2008-01-01

    Water hammer phenomena regularly occur in piping systems of nuclear power plants, e.g. after the rapid closure of valves. As the loads are usually several times higher than during normal operation pipe rupture is possible and therefore the integrity of the nuclear power plant can be endangered. In recent years extensive studies have been performed to assess the capabilities of the widely-used transient thermohydraulic system codes like RELAP5 for the simulation of water hammers and pressure surges in piping systems. The parameters affecting the results of such simulations are on the one side related to the numerical method, in particular the grid step size Δx and time step size Δt, and on the other hand to the models for present physical effects like the fluid-structure-interaction (FSI), unsteady friction or the release of dissolved air. In many studies experimental data obtained at the Fraunhofer Institute UMSICHT at Oberhausen/Germany has been used for code validation. In a vast campaign reliable data has been measured under varying boundary conditions for pressure surges in a pipe after a fast valve closure. Details of the experimental set-up are described in /1/ and /2/. Tiselj and Petelin /3/ provided theoretical background on the properties of the numerical scheme used by RELAP5 and Tiselj and Cerne /4/ highlighted the behavior at very small time steps. Kaliatka and al. /5/ investigated the influence of the grid step size and the time step size in RELAP5 on pressure transients obtained in UMSICHT experiments. Neuhaus and Dudlik /2/,/6/ studied the effects of fluidstructure- interaction, unsteady friction and degassing of dissolved air in tape-water filled pipes on pressure surges. They compared their numerical results again with experimental data from the UMSICHT test facility and observed a significant impact of all three parameters on the pressure-surge amplitudes and frequency. Barten and al. /15/ performed calculations of experiment 329 of the UMSICHT

  1. Ship localization in Santa Barbara Channel using machine learning classifiers.

    Science.gov (United States)

    Niu, Haiqiang; Ozanich, Emma; Gerstoft, Peter

    2017-11-01

    Machine learning classifiers are shown to outperform conventional matched field processing for a deep water (600 m depth) ocean acoustic-based ship range estimation problem in the Santa Barbara Channel Experiment when limited environmental information is known. Recordings of three different ships of opportunity on a vertical array were used as training and test data for the feed-forward neural network and support vector machine classifiers, demonstrating the feasibility of machine learning methods to locate unseen sources. The classifiers perform well up to 10 km range whereas the conventional matched field processing fails at about 4 km range without accurate environmental information.

  2. Analysis on shock wave speed of water hammer of lifting pipes for deep-sea mining

    Science.gov (United States)

    Zhou, Zhi-jin; Yang, Ning; Wang, Zhao

    2013-04-01

    Water hammer occurs whenever the fluid velocity in vertical lifting pipe systems for deep-sea mining suddenly changes. In this work, the shock wave was proven to play an important role in changing pressures and periods, and mathematical and numerical modeling technology was presented for simulated transient pressure in the abnormal pump operation. As volume concentrations were taken into account of shock wave speed, the experiment results about the pressure-time history, discharge-time history and period for the lifting pipe system showed that: as its concentrations rose up, the maximum transient pressure went down, so did its discharges; when its volume concentrations increased gradually, the period numbers of pressure decay were getting less and less, and the corresponding shock wave speed decreased. These results have highly coincided with simulation results. The conclusions are important to design lifting transporting system to prevent water hammer in order to avoid potentially devastating consequences, such as damage to components and equipment and risks to personnel.

  3. Genome sequence of the thermophile Bacillus coagulans Hammer, the type strain of the species.

    Science.gov (United States)

    Su, Fei; Tao, Fei; Tang, Hongzhi; Xu, Ping

    2012-11-01

    Here we announce a 3.0-Mb assembly of the Bacillus coagulans Hammer strain, which is the type strain of the species within the genus Bacillus. Genomic analyses based on the sequence may provide insights into the phylogeny of the species and help to elucidate characteristics of the poorly studied strains of Bacillus coagulans.

  4. Genome Sequence of the Thermophile Bacillus coagulans Hammer, the Type Strain of the Species

    OpenAIRE

    Su, Fei; Tao, Fei; Tang, Hongzhi; Xu, Ping

    2012-01-01

    Here we announce a 3.0-Mb assembly of the Bacillus coagulans Hammer strain, which is the type strain of the species within the genus Bacillus. Genomic analyses based on the sequence may provide insights into the phylogeny of the species and help to elucidate characteristics of the poorly studied strains of Bacillus coagulans.

  5. Reconsidering a Classic: Assessing the History of Women's Higher Education a Dozen Years after Barbara Solomon.

    Science.gov (United States)

    Eisenmann, Linda

    1997-01-01

    A critique of Barbara Miller Solomon's 1985 book "In the Company of Educated Women" identifies its ground-breaking contributions but shows how it limited women's educational history by overemphasizing access to higher education and neglecting wider influences such as economics, women's occupational choices, and women's status in society.…

  6. Child health in the workplace: the Supreme Court in Hammer v. Dagenhart (1918).

    Science.gov (United States)

    Berger, L R; Johansson, S R

    1980-01-01

    Exploitation of children in the labor force at the beginning of this century gave rise to a national campaign leading to congressional passage of the Keating-Owen Act in 1916. The act prohibited from interstate commerce goods produced in factories or mines that employed children who either were under fourteen years of age or who were under sixteen years of age and worked more than eight hours a day. Despite its popular support, the Act was declared unconstitutional by the Supreme Court in Hammer v. Dagenhart (1918). The Court's decision involved several major issues: interpretation of the Fifth and Fourteenth Amendments to the Constitution, freedom of contract, police power of the states, and the interstate commerce clause. Review of previous Court decisions suggests that the justices were on less than solid legal ground in reaching their decision. Examination of the historical context of the decision, however, suggests other factors that may have played a more important role than judicial precedents. The debate prompted by Hammer v. Dagenhart has much relevance to such current issues as young agricultural workers, sex discrimination in industry, and the powers of the federal government vis-a-vis states and individual citizens.

  7. Calculation of fluid (steam) hammer loading to piping systems by the response spectrum method

    International Nuclear Information System (INIS)

    Krause, G.; Schrader, W.; Leimbach, K.R.

    1983-01-01

    Today computations of fluid and steam hammer loading to piping systems are usually performed as a time-history analysis in which the transient pressure forces act as external excitations. For practical purposes it is desirable to be able to treat fluid hammer loading using the response spectrum method similarily as loads from external events. Two advantages arise from the use of spectra in the analysis of piping systems subjected to dynamic force excitations. Firstly, the response spectrum method is much less sensitive to model idealization than the time-history method. Secondly, computational efforts are reduced. In this paper the algorithm for the treatment of force excitations through the modal response spectrum method is briefly presented. The effect of the residuum accounting for higher modes which are not part of the modal decomposition is considered. In particular various methods of superposition of the responses of the dynamic forces and of the modes are investigated. Results and comparisons are presented of several response spectrum analyses and time-history analyses. (orig.)

  8. Comparison of fishes taken by a sportfishing party vessel around oil platforms and adjacent natural reefs near Santa Barbara, California

    International Nuclear Information System (INIS)

    Love, M.S.; Westphal, W.

    1990-01-01

    Since 1958, 29 oil platforms have been sited in the southern California Bight of which 28 still remain in place. However, little is known of the fish populations surrounding these structures, particularly those sited in water deeper than 30 m. In the course of research on the Santa Barbara, California, party vessel sport fishery, it was noted that the platforms off Santa Barbara supported considerable sportfishing activity. Those platforms, located to the southeast of Santa Barbara in depths of 48-62 m, were particularly important and were fished intensively for various rockfishes (genus Sebastes). When fishing a platform, the vessel pulled up to within 5-10 m of a platform and drifts along one side, with the vessel operator using intermittent power to keep it near the structure. Most of the desirable species, particularly rockfishes, remained close to the platforms, rarely venturing more than perhaps 20 m from the structure. The party vessels also spent considerable time fishing over nearby natural reefs. In this survey, it was noted that there appeared to be differences in species catch composition and fish size between oil platforms and these natural reefs. Increased offshore oil drilling off California has raised interest in the role platforms play in marine systems. Questions have been raised regarding what fish live around platforms, how these structures influence populations over surrounding reefs, and whether the platforms act as fish enhancers (promoting recruitment) or only as aggregators. These questions are particularly relevant when the platforms are to be decommissioned and the possibility of allowing them to remain as artificial reefs is raised. This paper describes the results of the study on the fish populations around oil platforms and nearby natural reefs off Santa Barbara

  9. Water hammer caused by closure of turbine safety spherical valves

    Science.gov (United States)

    Karadžić, U.; Bergant, A.; Vukoslavčević, P.

    2010-08-01

    This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perućica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.

  10. Water hammer caused by closure of turbine safety spherical valves

    International Nuclear Information System (INIS)

    Karadzic, U; Vukoslavcevic, P; Bergant, A

    2010-01-01

    This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perucica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.

  11. Water hammer caused by closure of turbine safety spherical valves

    Energy Technology Data Exchange (ETDEWEB)

    Karadzic, U; Vukoslavcevic, P [Faculty of Mechanical Engineering, University of Montenegro Dzordza Vasingtona nn, Podgorica, 81000 (Montenegro); Bergant, A, E-mail: uros.karadzic@ac.m [LitostrojPower d.o.o., Litostrojska 50, Ljubljana, 1000 (Slovenia)

    2010-08-15

    This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perucica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.

  12. Analysis of water hammer in two-component two-phase flows

    International Nuclear Information System (INIS)

    Warde, H.; Marzouk, E.; Ibrahim, S.

    1989-01-01

    The water hammer phenomena caused by a sudden valve closure in air-water two-phase flows must be clarified for the safety analysis of LOCA in reactors and further for the safety of boilers, chemical plants, pipe transport of fluids such as petroleum and natural gas. In the present work water hammer phenomena caused by sudden valve closure in two-component two-phase flows are investigated theoretically and experimentally. The phenomena are more complicated than in single phase-flows due to the fact of the presence of compressible component. Basic partial differential equations based on a one-dimensional homogeneous flow model are solved by the method of characteristic. The analysis is extended to include friction in a two-phase mixture depending on the local flow pattern. The profiles of the pressure transients, the propagation velocity of pressure waves and the effect of valve closure on the transient pressure are found. Different two-phase flow pattern and frictional pressure drop correlations were used including Baker, Chesholm and Beggs and Bril correlations. The effect of the flow pattern on the characteristic of wave propagation is discussed primarily to indicate the effect of void fraction on the velocity of wave propagation and on the attenuation of pressure waves. Transient pressure in the mixture were recorded at different air void fractions, rates of uniform valve closure and liquid flow velocities with the aid of pressure transducers, transient wave form recorders interfaced with an on-line pc computer. The results are compared with computation, and good agreement was obtained within experimental accuracy

  13. Analysis of water hammer in control rod drive systems of boiling water reactor nuclear power plants

    International Nuclear Information System (INIS)

    Safwat, H.H.; Arastu, A.H.; Lau, S.

    1983-01-01

    The method of characteristics is applied to analyze water hammer in BWR (Boiling Water Reactor) Control Rod Drive (CRD) Systems following fast opening of scram valves. The modelling of the CRD mechanism is presented. Numerical predictions are compared to experimental data. (author)

  14. Analysis of water hammer in pipelines by partial fraction expansion of transfer function in frequency domain

    International Nuclear Information System (INIS)

    Lee, Jun Shin; Lee, Wook Ryun; Oh, Ki Yong; Kim, Bong Ki

    2010-01-01

    Understanding water hammer is very important to the prevention of excessive pressure build-up in pipelines. Many researchers have studied this phenomenon, drawing effective solutions through the time- and frequency-domain approaches. For the purposes of enhancing the advantages of the frequency-domain approach and, thereby, rendering investigations of the dynamic characteristics of pipelines more effective, we propose partial fraction expansion of the transfer function between the unsteady flow source and a given section. We simulate the proposed approach using a vibration element inserted into a simple pipeline, deducing much useful physical information pertaining to pipeline design. We conclude that locating the resonance of the vibration element between the first and second resonances of the pipeline can mitigate the excessive pressure build-up attendant on the occurrence of water hammer. Our method of partial fraction expansion is expected to be useful and effective in analyses of unsteady flows in pipelines

  15. 75 FR 76453 - CAlifornians for Renewable Energy, Inc., (CARE), and Barbara Durkin v. National Grid, Cape Wind...

    Science.gov (United States)

    2010-12-08

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL11-9-000] CAlifornians for Renewable Energy, Inc., (CARE), and Barbara Durkin v. National Grid, Cape Wind, and the Massachusetts... Energy Regulatory Commission's (Commission) Rules of Practice and Procedure, 18 CFR 385.206, (2010...

  16. Hypothenar hammer syndrome: long-term results of vascular reconstruction.

    Science.gov (United States)

    Endress, Ryan D; Johnson, Craig H; Bishop, Allen T; Shin, Alexander Y

    2015-04-01

    To evaluate long-term patency rates and related outcomes after vascular reconstruction of hypothenar hammer syndrome and identify patient- or treatment-related factors that may contribute to differences in outcome. We used color flow ultrasound to determine the patency of 18 vein graft reconstructions of the ulnar artery at the wrist in 16 patients. Validated questionnaires evaluated patients' functional disability with the Disabilities of the Arm, Shoulder, and Hand score, pain with the visual analog scale, and cold intolerance with the Cold Intolerance Symptom Severity survey. Patient demographics, clinical data, and surgical factors were analyzed for association with graft failure. Patients were asked to grade the result of treatment on a scale of 0 to 10. Of 18 grafts, 14 (78%) were occluded at a mean of 118 months postoperatively. Patients with patent grafts had significantly less disability related to cold intolerance according to the Cold Intolerance Symptom Severity survey in addition to significantly less pain on the visual analog scale. There was no statistical difference in Disabilities of the Arm, Shoulder, and Hand scores between patients with patent or occluded grafts. Patients graded the result significantly higher in patent reconstructions. We noted a higher incidence of graft occlusion than previously reported at a mean follow-up of 9.8 years, which represents a long-duration follow-up study of surgical treatment of hypothenar hammer syndrome. Despite a high percentage of occlusion, overall, patients remained satisfied with low functional disability and all would recommend surgical reconstruction. This study suggests that improved outcomes may result from patent grafts in the long term. Prognostic IV. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  17. Investigation and mitigation of condensation induced water hammer by stratified flow experiments

    Science.gov (United States)

    Kadakia, Hiral J.

    This research primarily focuses on the possibility of using stratified flow in preventing an occurrence of condensation induced water hammer (CIWH) in horizontal pipe involving steam and subcooled water. A two-phase flow loop simulating the passive safety systems of an advanced light water reactor was constructed and a series of stratified flow experiments were carried out involving a system of subcooled water, saturated water, and steam. Special instruments were designed to measure steam flow rate and subcooled liquid velocity. These experiments showed that when flow field conditions meet certain criteria CIWH does occur. Flow conditions used in experiments were typically observed in passive safety systems of an advanced light water cooled reactor. This research summarizes a) literature research and other experimental data that signify an occurrence of CIWH, b) experiments in an effort to show an occurrence of CIWH and the ability to prevent CIWH, c) qualitative and quantitative results to underline the mechanism of CIWH, d) experiments that show CIWH can be prevented under certain conditions, and e) guidelines for the safe operating conditions. Based on initial experiment results it was observed that Bernoulli's effect can play an important role in wave formation and instability. A separate effect table top experiment was constructed with plexi-glass. A series of entrance effect tests and stratified experiments were carried out with different fluids to study wave formation and wave bridging. Special test series experiments were carried out to investigate the presence of a saturated layer. The effect of subcooled water and steam flow on wedge length and depth were recorded. These experiments helped create a model which calculates wedge and depth of wedge for a given condition of steam and subcooled water. A very good comparison between the experiment results and the model was obtained. These experiments also showed that the presence of saturated layer can mitigate

  18. Seismic response prediction for cabinets of nuclear power plants by using impact hammer test

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Ki Young [Department of Civil and Structural Engineering, University of Sheffield, Sheffield (United Kingdom); Gook Cho, Sung [JACE KOREA, Gyeonggi-do (Korea, Republic of); Cui, Jintao [Department of Civil Engineering, Kunsan National University, Jeonbuk (Korea, Republic of); Kim, Dookie, E-mail: kim2kie@kunsan.ac.k [Department of Civil Engineering, Kunsan National University, Jeonbuk (Korea, Republic of)

    2010-10-15

    An effective method to predict the seismic response of electrical cabinets of nuclear power plants is developed. This method consists of three steps: (1) identification of the earthquake-equivalent force based on the idealized lumped-mass system of the cabinet, (2) identification of the state-space equation (SSE) model of the system using input-output measurements from impact hammer tests, and (3) seismic response prediction by calculating the output of the identified SSE model under the identified earthquake-equivalent force. A three-dimensional plate model of cabinet structures is presented for the numerical verification of the proposed method. Experimental validation of the proposed method is carried out on a three-story frame which represents the structure of a cabinet. The SSE model of the frame is accurately identified by impact hammer tests with high fitness values over 85% of the actual frame characteristics. Shaking table tests are performed using El Centro, Kobe, and Northridge earthquakes as input motions and the acceleration responses are measured. The responses of the model under the three earthquakes are predicted and then compared with the measured responses. The predicted and measured responses agree well with each other with fitness values of 65-75%. The proposed method is more advantageous over other methods that are based on finite element (FE) model updating since it is free from FE modeling errors. It will be especially effective for cabinet structures in nuclear power plants where conducting shaking table tests may not be feasible. Limitations of the proposed method are also discussed.

  19. Library generation and tests for the HAMMER system from the ENDF/B-IV data

    International Nuclear Information System (INIS)

    Queiroz Bogado Leite, S. de; Chalhoub, E.S.; Moraes, Marisa de.

    1983-05-01

    The modifications made to a number of programs belonging to the HAMMER system in order to process data from ENDF/B-IV are presented. An alternate scheme of representing the resonance region by means of extensive tabulation of profiles is made available for selected materials. Numerical examples illustrate comparisons of the results obtained with these libraries against those from the literature. (Author) [pt

  20. Environmental Audit at Santa Barbara Operations, Special Technologies Laboratory, Remote Sensing Laboratory, North Las Vegas Facilities

    International Nuclear Information System (INIS)

    1991-03-01

    This report documents the results of the Environmental Audit of selected facilities under the jurisdiction of the DOE Nevada Operations Office (NV) that are operated by EG and G Energy Measurements, Incorporated (EG and G/EM). The facilities included in this Audit are those of Santa Barbara Operation (SBO) at Goleta, California; the Special Technologies Laboratory (STL) at Santa Barbara, California; and Las Vegas Area Operations (LVAO) including the Remote Sensing Laboratory (RSL) at Nellis Air Force Base in Nevada, and the North Las Vegas Facilities (NLVF) at North Las Vegas, Nevada. The Environmental Audit was conducted by the US Department of Energy's (DOE) Office of Environmental Audit, commencing on January 28, 1991 and ending on February 15, 1991. The scope of the Audit was comprehensive, addressing environmental activities in the technical areas of air, surface water/drinking water, groundwater, waste management, toxic and chemical materials, quality assurance, radiation, inactive waste sites, and environmental management. Also assessed was compliance with applicable Federal, state, and local regulations and requirements; internal operating requirements; DOE Orders; and best management practices. 8 tabs

  1. On the importance of valve modelling, reflected pressures, and wall friction, in CATHENA water hammer simulations

    International Nuclear Information System (INIS)

    Beuthe, T.G.

    1998-01-01

    The results of code and modelling developments outlined in this paper show that CATHENA can be used to accurately model the behaviour of valve slam generated water hammer if sufficient care and detail are used to model the characteristics of the valve. It also shows that CATHENA can accurately predict the reflection and transmission of travelling water pressure waves at expansions, contractions, and dead ends. Finally, although CATHENA is capable of accurately predicting the critical phenomena observed in water hammer, the inter-peak timing of the pressure excursions is not well predicted when significant bulk flows occur. The use of an unsteady wall friction factor to correct for this discrepancy has been examined, but the implementation of relationships suggested in the literature provided too much damping. A good match between experimental and simulation data can be achieved, but it is suggested that the default implementation of such a relationship take place only after an investigation of further potential loss terms can be completed. (author)

  2. Modal spectrum analysis of piping systems under water-hammer loading: Spectra examination

    International Nuclear Information System (INIS)

    Meder, G.; Grams, J.

    1983-01-01

    In the last few years the dynamic calculation with spectra of piping systems under fluid-hammer has been developed. In comparison with the time-history solution method the spectra method has important advantages because it can calculate a bounded solution. In this bounded solution, the inevitable uncertainties of the time-dependent forces and the uncertainties in the modeling of the piping system are taken into account. The spectra also give valuable information about the frequency content of the time-dependent forces, which is important too for correct time-step selection when using the time-history-method. Using the spectra method, the dynamic calculation is divided into stages. First and most essential is the calculation of the spectra. Secondly, a form of superposition is used for combining the results from each eigenmode analysis. In this paper the first stage, calculation of the spectra due to fluid hammer loading, will be examined. An approximate method for load calculation is shown, whereby the results from a change of fluid-dynamic parameters can be quickly determined without making a full numerical analysis. When changes are made in fluiddynamic parameters, the normal result is a change of shift in the frequency content of the spectra. However, for changes in certain parameters, only the force amplitudes are changed. Both types of changes will be discussed. (orig./RW)

  3. Mineralogical characterization of the argillaceous material from the Municipality of Santa Barbara, Para, Brazil

    International Nuclear Information System (INIS)

    Hildebrando, E.A.; Sheller, T.; Angelica, R.S.; Neves, R.S.

    2009-01-01

    In the present work were investigated mineralogical phases in a material with argillaceous characteristic of the region of Genipauba, Santa Barbara, State of Para. Characterization of the collected sample was performed by X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG) and infrared spectroscopy (IR). The results of the assays indicate the presence of the clay minerals like kaolinite and muscovite, as well as minerals as quartz and anatase. (author)

  4. Minimising the risk of water hammer and other problems at the beginning of stagnation of solar thermal plants - A theoretical approach

    International Nuclear Information System (INIS)

    Streicher, W.

    2000-01-01

    Solar plants are increasingly used not only for hot tap water heating but also for the assistance of space heating. These plants produce much more energy in summer than needed, which often results in stagnation. Because of stagnation-temperatures of todays selective collectors up to 200 deg. C, the collector fluid evaporates. In several plants a high noise level and a vibration of the plant during this evaporation phase is reported. This is due to the occurrence of water hammers in the system, when liquid collector fluid passes areas where the fluid was already evaporated and superheated. The remaining vapor bubbles deflate rapidly and the liquid phases collide with high velocity, which results in a rapid pressure increase. This paper describes the theory of condensate-induced water hammers and conditions of solar plants, under which this can happen. A simulation model for the evaporation phase of the collector is presented to give a deeper understanding about the influences of solar radiation, the size of the tubing, and the size of the expansion device on the process of the evaporation. Three hydraulic layouts of the collector area are discussed for there possibilities producing water hammers. (au)

  5. Coccolithophore response to the 1997-1998 El Niño in Santa Barbara Basin (California)

    NARCIS (Netherlands)

    De Bernardi, B.; Ziveri, P.; Erba, E.; Thunell, R.C.

    2005-01-01

    The response of coccolithophore export production to non-El Niño and El Niño conditions was monitored during a two year period (26 March 1996-3 April 1998) in the centre of the Santa Barbara Basin (34°14′ N; 120°02′ W), California borderland. During the 1997-1998 El Niño the seasonal cycle of the

  6. 击弦乐器乐声特性与演奏手法的关系%Relationship between hammered string instrument musical sound characteristic and playing skills

    Institute of Scientific and Technical Information of China (English)

    任静锋; 王旸; 龙姝明

    2012-01-01

    给定初值条件,解弦振动波动定解问题,计算演奏手法变化引起的击弦乐器振动驻波能谱结构变化.探索击弦乐器乐声的音调、音色与弦振动驻波能谱结构的关系.用Mathematica编程模拟击弦乐器弦振动乐声,用听觉体验和频谱分析研究击弦乐器音调、音色与演奏手法的关系.%Given initial conditions, string vibration wave problem was solved. By changing playing techniques, calculation of the change caused by hammered string instrument vibration energy spectrum. Explore the relationship of the hammered string instrument tone and timbre and string vibration energy spectrum was exploved. Mathematics programming was used to simulate the hammered string instrument music. By auditory experience and spectrum analysis, the relationship between the hammered string instrument tone and timbre and playing techniques was studied.

  7. Simulation of water hammer phenomena using the system code ATHLET

    Energy Technology Data Exchange (ETDEWEB)

    Bratfisch, Christoph; Koch, Marco K. [Bochum Univ. (Germany). Reactor Simulation and Safety Group

    2017-07-15

    Water Hammer Phenomena can endanger the integrity of structures leading to a possible failure of pipes in nuclear power plants as well as in many industrial applications. These phenomena can arise in nuclear power plants in the course of transients and accidents induced by the start-up of auxiliary feed water systems or emergency core cooling systems in combination with rapid acting valves and pumps. To contribute to further development and validation of the code ATHLET (Analysis of Thermalhydraulics of Leaks and Transients), an experiment performed in the test facility Pilot Plant Pipework (PPP) at Fraunhofer UMSICHT is simulated using the code version ATHLET 3.0A.

  8. Investigation of the Hammer-Gamma measurement technique: A feasibility study

    International Nuclear Information System (INIS)

    Showalter, R.

    1987-05-01

    As a reconnaissance tool for the determination of the approximate extent of shallow subsurface radium contamination, various detectors were evaluated to determine the most appropriate size for use in this task. Measurements were taken in the calibration models with existing instrumentation to determine sensitivities and calibration factors. Field measurements were taken to ensure subsurface contamination could be located with the instrumentation selected. Various methods of constructing a slim and shallow borehole were investigated to determine the easiest and quickest method of inserting the detector into the ground. Based on these investigations, a prototype ''Hammer-Gamma'' system was designed, built, and tested. 7 refs., 4 figs., 4 tabs

  9. Simulation of water hammer phenomena using the system code ATHLET

    International Nuclear Information System (INIS)

    Bratfisch, Christoph; Koch, Marco K.

    2017-01-01

    Water Hammer Phenomena can endanger the integrity of structures leading to a possible failure of pipes in nuclear power plants as well as in many industrial applications. These phenomena can arise in nuclear power plants in the course of transients and accidents induced by the start-up of auxiliary feed water systems or emergency core cooling systems in combination with rapid acting valves and pumps. To contribute to further development and validation of the code ATHLET (Analysis of Thermalhydraulics of Leaks and Transients), an experiment performed in the test facility Pilot Plant Pipework (PPP) at Fraunhofer UMSICHT is simulated using the code version ATHLET 3.0A.

  10. Steam condensation induced water hammer simulations for different pipelines

    International Nuclear Information System (INIS)

    Barna, I.F.; Ezsol, G.

    2011-01-01

    We investigate steam condensation induced water hammer (CIWH) phenomena and present theoretical results for different kind of pipelines. We analyze the process with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. At first, we present calculations for various pipelines in the VVER-440-312 type nuclear reactor. Our recent calculation clearly shows that the six conditions of Griffith are only necessary conditions for CIWH but not sufficient. As second results we performed calculations for various geometries and compare with the theory of Chun. (author)

  11. Transient Analysis for Evaluating the Potential Boiling in the High Elevation Emergency Cooling Units of PWR Following a Hypothetical Loss of Coolant Accident (LOCA) and Subsequent Water Hammer Due to Pump Restart

    International Nuclear Information System (INIS)

    Husaini, S. Mahmood; Qashu, Riyad K.

    2004-01-01

    The Generic Letter GL-96-06 issued by the U.S. Nuclear Regulatory Commission (NRC) required the utilities to evaluate the potential for voiding in their Containment Emergency Cooling Units (ECUs) due to a hypothetical Loss Of Coolant Accident (LOCA) or a Main Steam Line Break (MSLB) accompanied by the Loss Of Offsite Power (LOOP). When the offsite power is restored, the Component Cooling Water (CCW) pumps restart causing water hammer to occur due to cavity closure. Recently EPRI (Electric Power Research Institute) performed a research study that recommended a methodology to mitigate the water hammer due to cavity closure. The EPRI methodology allows for the cushioning effects of hot steam and released air, which is not considered in the conventional water column separation analysis. The EPRI study was limited in scope to the evaluation of water hammer only and did not provide any guidance for evaluating the occurrence of boiling and the extent of voiding in the ECU piping. This paper presents a complete methodology based on first principles to evaluate the onset of boiling. Also, presented is a methodology for evaluating the extent of voiding and the water hammer resulting from cavity closure by using an existing generalized computer program that is based on the Method of Characteristics. The EPRI methodology is then used to mitigate the predicted water hammer. Thus it overcomes the inherent complications and difficulties involved in performing hand calculations for water hammer. The heat transfer analysis provides an alternative to the use of very cumbersome modeling in using CFD (computational fluid dynamics) based computer programs. (authors)

  12. Numerical and experimental investigations of water hammers in nuclear industry

    Directory of Open Access Journals (Sweden)

    R Messahel

    2016-10-01

    Full Text Available In nuclear and petroleum industries, supply pipes are often exposed to high pressure loading which can cause to the structure high strains, plasticity and even, in the worst scenario, failure. Fast Hydraulic Transient phenomena such as Water Hammers (WHs are of this type. It generates a pressure wave that propagates in the pipe causing high stress. Such phenomena are of the order of few msecs and numerical simulation can offer a better understanding and an accurate evaluation of the dynamic complex phenomenon including fluid-structure interaction, multi-phase flow, cavitation … For the last decades, the modeling of phase change taking into account the cavitation effects has been at the centre of many industrial applications (chemical engineering, mechanical engineering, … and has a direct impact on the industry as it might cause damages to the installation (pumps, propellers, control valves, …. In this paper, numerical simulation using FSI algorithm and One-Fluid Cavitation models ("Cut-Off" and "HEM (Homogeneous Equilibrium Model Phase-Change" introduced by Saurel et al. [1] of WHs including cavitation effects is presented.

  13. Validity of the Water Hammer Formula for Determining Regional Aortic Pulse Wave Velocity: Comparison of One-Point and Two-Point (Foot-to-Foot) Measurements Using a Multisensor Catheter in Human.

    Science.gov (United States)

    Hanya, Shizuo

    2013-01-01

    Lack of high-fidelity simultaneous measurements of pressure and flow velocity in the aorta has impeded the direct validation of the water-hammer formula for estimating regional aortic pulse wave velocity (AO-PWV1) and has restricted the study of the change of beat-to-beat AO-PWV1 under varying physiological conditions in man. Aortic pulse wave velocity was derived using two methods in 15 normotensive subjects: 1) the conventional two-point (foot-to-foot) method (AO-PWV2) and 2) a one-point method (AO-PWV1) in which the pressure velocity-loop (PV-loop) was analyzed based on the water hammer formula using simultaneous measurements of flow velocity (Vm) and pressure (Pm) at the same site in the proximal aorta using a multisensor catheter. AO-PWV1 was calculated from the slope of the linear regression line between Pm and Vm where wave reflection (Pb) was at a minimum in early systole in the PV-loop using the water hammer formula, PWV1 = (Pm/Vm)/ρ, where ρ is the blood density. AO-PWV2 was calculated using the conventional two-point measurement method as the distance/traveling time of the wave between 2 sites for measuring P in the proximal aorta. Beat-to-beat alterations of AO-PWV1 in relationship to aortic pressure and linearity of the initial part of the PV-loop during a Valsalva maneuver were also assessed in one subject. The initial part of the loop became steeper in association with the beat-to-beat increase in diastolic pressure in phase 4 during the Valsalva maneuver. The linearity of the initial part of the PV-loop was maintained consistently during the maneuver. Flow velocity vs. pressure in the proximal aorta was highly linear during early systole, with Pearson's coefficients ranging from 0.9954 to 0.9998. The average values of AO-PWV1 and AO-PWV2 were 6.3 ± 1.2 and 6.7 ± 1.3 m/s, respectively. The regression line of AO-PWV1 on AO-PWV2 was y = 0.95x + 0.68 (r = 0.93, p <0.001). This study concluded that the water-hammer formula (one-point method) provides

  14. Excellent women : the novels of Barbara Pym and Anita Brookner / Elizabeth Susanna van Aswegen

    OpenAIRE

    Van Aswegen, E. S. (Elizabeth Susanna)

    1987-01-01

    From 1950, until her death in 1980, Barbara Pym published ten novels. The social climate of the 'sixties and early 'seventies was not receptive to her subtle literary style, and her writing suffered an eclipse of 16 years. A renaissance in her fortunes came in January 1977, when the Times Literary Supplement asked a selection of critics to say which writers they considered the most underrated of the twentieth century; both Philip Larkin and Lord David Cecil selected Pym as o...

  15. Development of a 1 D hybrid HTC model using CFD simulations for the analysis of direct contact condensation as the driving force for water hammers

    Energy Technology Data Exchange (ETDEWEB)

    Ceuca, Christian Sabin; Macian-Juan, Rafael [Technische Univ. Muenchen (Germany). Lehrstuhl fuer Nukleartechnik

    2013-03-15

    A Hybrid Heat Transfer Coefficient module has been developed based on two Surface Renewal Theory models using CFD simulations. The validation of the model has been done on a meso-scale computational grid for CFD simulations and on a macro-scale computational grid for System Code analysis. The CFD simulation was performed for a stratified co-current two phase flow between saturated steam and sub-cooled water while the System Code analysis was performed for a Condensation Induced Water Hammer experiment. (orig.)

  16. Rezension von: Barbara Holland-Cunz: Gefährdete Freiheit. Über Hannah Arendt und Simone de Beauvoir. Opladen u.a.: Verlag Barbara Budrich 2012.

    Directory of Open Access Journals (Sweden)

    Mirjam Dierkes

    2012-11-01

    Full Text Available Von Barbara Holland-Cunz, die sich mit Simone de Beauvoir und Hannah Arendt bereits einzeln beschäftigt hat, liegt nun ein Band vor, in dem sie sich diesen herausragenden Denkerinnen des 20. Jahrhunderts gemeinsam widmet. In einer beinahe synoptisch anmutenden Herangehensweise fokussiert sie dabei auf den Begriff der Freiheit, der bei beiden von eminenter Bedeutung für das jeweilige Theoriegebäude ist. Holland-Cunz zufolge verstehen beide, bei einigen Unterschieden, Freiheit so, dass sie sich vor allem durch eine in sich eingeschriebene Gefährdung auszeichnet: Diese resultiert aus einem heroisch-emphatischen Gestus, der in paradoxer Weise gepaart wird mit einem abgeklärten Realismus. Über weite Strecken liest sich der Weg zu dieser Deutung, v. a. auch wegen einer teilweise sympathisch unkonventionellen und originellen Herangehensweise, sehr anregend und überzeugend.

  17. Dad's in the Garage: Santa Barbara Physicists in the Long 1970s

    Science.gov (United States)

    Mody, Cyrus

    2013-03-01

    American physicists faced many challenges in the 1970s: declining research budgets; public skepticism of scientific authority; declining student enrollments; and pressure to shift to topics such as biomedicine, environmental remediation, alternative energy, public housing and transport, and disability technologies. This paper examines the responses to these challenges of a small group of Santa Barbara physicists. While this group is not representative of the American physics profession, the success and failure of their responses to changed conditions tells us something about how American physicists got through the 1970s, and about the origins of some features of American physics today. The three physicists examined here are Philip Wyatt, David Phillips, and Virgil Elings. In the late `60s, Wyatt left a defense think tank to found an instrumentation firm. The Santa Barbara oil spill and other factors pushed that firm toward civilian markets in biomedicine and pollution measurement. Phillips joined Wyatt's firm from UCSB, while also founding his own company, largely to sell electronic devices for parapsychology. Phillips was also the junior partner in a master's of scientific instrumentation degree curriculum founded by Elings in order to save UCSB Physics' graduate program. Through the MSI program, Elings moved into biomedical research and became a serial entrepreneur. By the 1990s, Wyatt, Phillips, and Elings' turn toward academic entrepreneurship, dual military-civilian markets for physics start-ups, and interdisciplinary collaborations between physicists and life scientists were no longer unusual. Together, their journey through the `70s shows how varied the physics' profession's response to crisis was, and how much it pivoted on new interactions between university and industry.

  18. Evaluation of SPT energy for Donut and Safety hammers using CPT measurements in Egypt

    OpenAIRE

    Rami M. El-Sherbiny; Manal A. Salem

    2013-01-01

    Standard Penetration Test (SPT) blow counts require correction prior to utilization in soil characterization and determination of properties and behavior. Among the most important corrections is the energy correction required to adjust the blow counts to 60% energy efficiency. However, there are no published data supporting commonly used value in Egypt. This paper presents an evaluation of the energy efficiency of the Donut and Safety hammers commonly used in Egypt and the associated energy c...

  19. Assessment of a potential rapid condensation induced water hammer in a passive auxiliary feedwater system

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Shin, Byung Soo; Do, Kyu Sik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Moody, Frederick J. [General Electric (Retired), CA (United States)

    2012-10-15

    A passive auxiliary feedwater system (PAFS) which is incorporated in the APR+ system is a kind of closed natural circulation loop. The PAFS has no operating functions during normal plant operation, but it has a dedicated safety function of the residual heat removal following initiating events, including the unlikely event of the most limiting single failure occurring coincident with a loss of offsite power, when the feedwater system becomes inoperable or unavailable. Even in the unlikely event of a station blackout, the isolation valves can be opened either by DC power or manual operation and then the PAFS can also provide adequate condensate to the steam generator (SG). The PAFS piping in the vicinity of each of the two SGs is designed to minimize the potential for destructive water hammer during start up operation by setting the stroke time for full close or full open of the condensate isolation valves upon receipt of a passive auxiliary feedwater actuation signal. The temperature of the stagnant condensate water and its surrounding tubes and piping during the reactor normal operation modes may fall to the ambient temperature. A possible concern is the introduction of saturated steam into the PAFS recirculation pipe downstream of the PCHX in the beginning of the PAFS operation. Although the steam introduction rate is expected to be slow, a rapid condensation rate is expected due to the initial cold surrounding temperature in the pipe, which could result in a localized pressure reduction and the propagation of decompression and velocity disturbances into the condensate water leg, which might cause the sudden closure of check valves and associated water hammer. Thus, it is requisite for the licensing review of the PAFS design to confirm if destructive water hammers will not be produced due to such rapid condensation induced decompressions in the system. This paper addresses an assessment of the potential local decompressions which could result from the steam

  20. "Romeo ja Julia" Liivimaa moodi? Barbara von Tiesenhauseni legend : ajalooline tagapõhi ja kirjanduslikud variatsioonid / Juhan Kreem, Liina Lukas

    Index Scriptorium Estoniae

    Kreem, Juhan

    2008-01-01

    Käsitletakse järgnevaid ilukirjanduslikke teoseid: Fr. R. Kreutzwaldi ballaadi "Das Fräulein von Borkholm", Th. H. Panteniuse romaani "Die von Kelles" (e.k. "Kelleste omad. Romaan Liivimaa minevikust"), Marie Underi ballaadi "Porkuni preili", Aino Kallase novelli "Barbara von Tiesenhusen" ja Maimu Bergi romaani "Kirjutajad"

  1. Offshore wind turbine foundations. Development of a special vibratory hammer with enhanced function; Gruendung von Offshore Windenergieanlagen. Entwicklung einer speziellen Vibrationsramme mit erweiterter Funktion

    Energy Technology Data Exchange (ETDEWEB)

    Koecher, Johannes; Ulrich, Dirk [ThyssenKrupp Tiefbautechnik GmbH, Alsfeld (Germany)

    2013-11-01

    To ensure that steel jacket foundations for offshore wind turbines are securely anchored, they are fixed to the seabed by means of ''pins''. The pins consist of pipe piles weighing up to 140 metric tons, and are driven into the seabed by a vibratory hammer and then anchored by impact driving. ThyssenKrupp Tiefbautechnik has modified a vibratory hammer so that it can pick up the piles horizontally directly from the working ship or pontoon and then vibrate them vertically into the ground. This significantly reduces installation times and foundation costs. (orig.)

  2. 33 CFR 167.452 - In the Santa Barbara Channel: Between Point Conception and Point Arguello.

    Science.gov (United States)

    2010-07-01

    ....452 In the Santa Barbara Channel: Between Point Conception and Point Arguello. (a) A separation zone... 120°30.16′ W. 34°18.90′ N 120°30.96′ W. 34°25.70′ N 120°51.81′ W. 34°23.75′ N 120°52.51′ W. (b) A traffic lane for westbound traffic is established between the separation zone and a line connecting the...

  3. The Schmidt hammer as a relative-age dating tool and its potential for calibrated-age dating in Holocene glaciated environments

    Science.gov (United States)

    Shakesby, Richard A.; Matthews, John A.; Owen, Geraint

    2006-11-01

    The Schmidt hammer is a relatively cheap, portable, sturdy instrument with proven value over the last two decades or so in rapidly dating coarse inorganic deposits of diverse origins. Early views were that its dating role was limited to distinguishing recently exposed from much older. Typically, either a few sites of possibly different ages or occasional older surfaces amongst many young sites were studied. More recently, calibration curves based on individual R-value means from small numbers (2-4) of sites of known ages have been used to estimate the ages of undated sites. We present Schmidt hammer rebound ( R-) values from 28 'Little Ice Age' (and younger), 23 Preboreal and 7 Younger Dryas glaciated surfaces in southern Norway in order, first, to test rigorously the robustness of the instrument as a relative-age dating tool. Despite being obtained from different surfaces (moraines, glaciofluvial deposits and bedrock) and varied metamorphic lithologies, the R-value overall means and 95% confidence intervals for the 'Little Ice Age', Preboreal and Younger Dryas age categories (respectively, 60.0±1.6, 41.6±1.4 and 34.2±2.0) are statistically significantly different. Only two outlying sites in the two younger age categories have overlapping confidence intervals, demonstrating remarkable robustness in differentiating early- and late-Holocene surfaces. The distinction between Preboreal and Younger Dryas sites (with terminal dates factors, including some previously considered critical (instrument wear, operator bias, initial rock surface texture), which emerge either as less important than previously argued or as relatively unimportant, together with others previously unreported (e.g. long-term changes in lichen, soil, snow and vegetation covers). Third, we investigate the potential for calibrated-age dating by applying exploratory, linear rates of R-value decline to selected combinations of sites. The results suggest that error limits of ca ±700 to ±1600 years

  4. Variable Step Integration Coupled with the Method of Characteristics Solution for Water-Hammer Analysis, A Case Study

    Science.gov (United States)

    Turpin, Jason B.

    2004-01-01

    One-dimensional water-hammer modeling involves the solution of two coupled non-linear hyperbolic partial differential equations (PDEs). These equations result from applying the principles of conservation of mass and momentum to flow through a pipe, and usually the assumption that the speed at which pressure waves propagate through the pipe is constant. In order to solve these equations for the interested quantities (i.e. pressures and flow rates), they must first be converted to a system of ordinary differential equations (ODEs) by either approximating the spatial derivative terms with numerical techniques or using the Method of Characteristics (MOC). The MOC approach is ideal in that no numerical approximation errors are introduced in converting the original system of PDEs into an equivalent system of ODEs. Unfortunately this resulting system of ODEs is bound by a time step constraint so that when integrating the equations the solution can only be obtained at fixed time intervals. If the fluid system to be modeled also contains dynamic components (i.e. components that are best modeled by a system of ODEs), it may be necessary to take extremely small time steps during certain points of the model simulation in order to achieve stability and/or accuracy in the solution. Coupled together, the fixed time step constraint invoked by the MOC, and the occasional need for extremely small time steps in order to obtain stability and/or accuracy, can greatly increase simulation run times. As one solution to this problem, a method for combining variable step integration (VSI) algorithms with the MOC was developed for modeling water-hammer in systems with highly dynamic components. A case study is presented in which reverse flow through a dual-flapper check valve introduces a water-hammer event. The predicted pressure responses upstream of the check-valve are compared with test data.

  5. A study for a guide chart of lower and upper boundary regions to avoid the condensation-induced water hammer in a long horizontal pipe

    International Nuclear Information System (INIS)

    Lee, Byung Jin

    1995-02-01

    Effects of the key system parameters such as the pipe length, the pipe diameter, the feedwater temperature and the system pressure on the critical flow rates of both the upper and the lower boundaries have been examined for long horizontal pipes. The upper and lower critical flow rates are sensitive to the pipe diameter, the pipe length and the system pressure, but not to the feedwater temperature over the practical operating ranges. Guide charts of the CIWH region boundary have been developed to be used in the system design and operation to predict the operating conditions vulnerable to the CIWH. The charts illustrate a series of the operating ranges bounded by the lower and the upper limiting curves where the water hammer is very likely to occur. A design and operational procedure has also been provided to help the designer and the operator to avoid the CIWH

  6. Report on data from the Nearshore Sediment Transport Study experiment at Leadbetter Beach, Santa Barbara, California, January-February 1980 (NODC Accession 8200080)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — THIS DATA SET CONSISTS OF THE RESULTS OF THE NEARSHORE SEDIMENT Nearshore Sediment Transport Study at Leadbetter Beach, Santa Barbara, California. These data from 28...

  7. Pipe rupture and steam/water hammer design loads for dynamic analysis of piping systems

    International Nuclear Information System (INIS)

    Strong, B.R. Jr.; Baschiere, R.J.

    1978-01-01

    The design of restraints and protection devices for nuclear Class I and Class II piping systems must consider severe pipe rupture and steam/water hammer loadings. Limited stress margins require that an accurate prediction of these loads be obtained with a minimum of conservatism in the loads. Methods are available currently for such fluid transient load development, but each method is severely restricted as to the complexity and/or the range of fluid state excursions which can be simulated. This paper presents a general technique for generation of pipe rupture and steam/water hammer design loads for dynamic analysis of nuclear piping systems which does not have the limitations of existing methods. Blowdown thrust loadings and unbalanced piping acceleration loads for restraint design of all nuclear piping systems may be found using this method. The technique allows the effects of two-phase distributed friction, liquid flashing and condensation, and the surrounding thermal and mechanical equipment to be modeled. A new form of the fluid momentum equation is presented which incorporates computer generated fluid acceleration histories by inclusion of a geometry integral termed the 'force equivalent area' (FEA). The FEA values permit the coupling of versatile thermal-hydraulic programs to piping dynamics programs. Typical applications of the method to pipe rupture problems are presented and the resultant load histories compared with existing techniques. (Auth.)

  8. Drop Hammer Tests with Three Oleo Strut Models and Three Different Shock Strut Oils at Low Temperatures

    Science.gov (United States)

    Kranz, M

    1954-01-01

    Drop hammer tests with different shock strut models and shock strut oils were performed at temperatures ranging to -40 C. The various shock strut models do not differ essentially regarding their springing and damping properties at low temperatures; however, the influence of the different shock strut oils on the springing properties at low temperatures varies greatly.

  9. Numerical simulation of water hammer in low pressurized pipe: comparison of SimHydraulics and Lax-Wendroff method with experiment

    Science.gov (United States)

    Himr, D.

    2013-04-01

    Article describes simulation of unsteady flow during water hammer with two programs, which use different numerical approaches to solve ordinary one dimensional differential equations describing the dynamics of hydraulic elements and pipes. First one is Matlab-Simulink-SimHydraulics, which is a commercial software developed to solve the dynamics of general hydraulic systems. It defines them with block elements. The other software is called HYDRA and it is based on the Lax-Wendrff numerical method, which serves as a tool to solve the momentum and continuity equations. This program was developed in Matlab by Brno University of Technology. Experimental measurements were performed on a simple test rig, which consists of an elastic pipe with strong damping connecting two reservoirs. Water hammer is induced with fast closing the valve. Physical properties of liquid and pipe elasticity parameters were considered in both simulations, which are in very good agreement and differences in comparison with experimental data are minimal.

  10. Numerical simulation of water hammer in low pressurized pipe: comparison of SimHydraulics and Lax-Wendroff method with experiment

    Directory of Open Access Journals (Sweden)

    Himr D.

    2013-04-01

    Full Text Available Article describes simulation of unsteady flow during water hammer with two programs, which use different numerical approaches to solve ordinary one dimensional differential equations describing the dynamics of hydraulic elements and pipes. First one is Matlab-Simulink-SimHydraulics, which is a commercial software developed to solve the dynamics of general hydraulic systems. It defines them with block elements. The other software is called HYDRA and it is based on the Lax-Wendrff numerical method, which serves as a tool to solve the momentum and continuity equations. This program was developed in Matlab by Brno University of Technology. Experimental measurements were performed on a simple test rig, which consists of an elastic pipe with strong damping connecting two reservoirs. Water hammer is induced with fast closing the valve. Physical properties of liquid and pipe elasticity parameters were considered in both simulations, which are in very good agreement and differences in comparison with experimental data are minimal.

  11. 76 FR 60376 - Revisions to the California State Implementation Plan, Santa Barbara Air Pollution Control...

    Science.gov (United States)

    2011-09-29

    ...EPA is taking direct final action to approve revisions to the Santa Barbara Air Pollution Control District (SBAPCD), Sacramento Municipal Air Quality Management District (SMAQMD) and South Coast Air Quality Management District (SCAQMD) portions of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) emissions from solvent cleaning machines and solvent cleaning operations and oil and gas production wells. We are approving local rules that regulate these emission sources under the Clean Air Act as amended in 1990 (CAA or the Act).

  12. 76 FR 60405 - Revisions to the California State Implementation Plan, Santa Barbara Air Pollution Control...

    Science.gov (United States)

    2011-09-29

    ...EPA is proposing to approve revisions to the Santa Barbara Air Pollution Control District (SBAPCD), Sacramento Municipal Air Quality Management District (SMAQMD) and South Coast Air Quality Management District (SCAQMD) portions of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) emissions from solvent cleaning machines and solvent cleaning operations and oil and gas production wells. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act as amended in 1990 (CAA or the Act).

  13. 76 FR 5319 - Revisions to the California State Implementation Plan, Santa Barbara Air Pollution Control...

    Science.gov (United States)

    2011-01-31

    ...EPA is proposing to approve revisions to the Santa Barbara Air Pollution Control District (SBAPCD), Placer County Air Pollution Control District (PCAPCD), Antelope Valley Air Quality Management District (AVAQMD), and Ventura County Air Pollution Control District (VCAPCD) portion of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) emissions from gasoline bulk plants, terminals and vehicle dispensing facilities. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act as amended in 1990 (CAA or the Act).

  14. Analysis of water hammer in a penstock in the case of valve closure. Part 2: Pressure losses concentrated downstream

    Directory of Open Access Journals (Sweden)

    Hocine HAMMOUM

    2017-06-01

    Full Text Available In our previous study (Part 1; by using the graphic of Bergeron, we have drawn the relationships which allow calculating flows and pressures at the valve and the reservoir, considering that pressure losses are negligible. Now, we assume in this second contribution that these pressure losses are concentrated downstream of the pipe, just at the entry of the valve. The study will focus on water hammer-induced by a slow closing of the valve. A practical example will be presented at the end of this work in order to illustrate the exposed method.

  15. An Interview with Barbara Keogh: Observations of Her Career and the Role of Context in Understanding Children with Disabilities

    Science.gov (United States)

    Chamberlain, Steven P.

    2011-01-01

    Barbara Keogh is a true Californian. She was born in Glendale, received her education and professional training in California colleges and universities, and has been a professor at the University of California, Los Angeles (UCLA) for more than 40 years, where she is now Emerita. She is a licensed clinical psychologist and has worked as a…

  16. Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

    International Nuclear Information System (INIS)

    Elmsheuser, Johannes; Legger, Federica; Llamas, Ramón Medrano; Sciabà, Andrea; García, Mario Úbeda; Ster, Daniel van der; Sciacca, Gianfranco

    2012-01-01

    Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion policies. A study of the historical test results for ATLAS, CMS and LHCb will be presented, including comparisons between the experiments’ grid availabilities and a search for site-based or temporal failure correlations. Finally, we will look to future plans that will allow users to gain new insights into the test results; these include developments to allow increased testing concurrency, increased scale in the number of metrics recorded per test job (up to hundreds), and increased scale in the historical job information (up to many millions of jobs per VO).

  17. Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

    Science.gov (United States)

    Elmsheuser, Johannes; Medrano Llamas, Ramón; Legger, Federica; Sciabà, Andrea; Sciacca, Gianfranco; Úbeda García, Mario; van der Ster, Daniel

    2012-12-01

    Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion policies. A study of the historical test results for ATLAS, CMS and LHCb will be presented, including comparisons between the experiments’ grid availabilities and a search for site-based or temporal failure correlations. Finally, we will look to future plans that will allow users to gain new insights into the test results; these include developments to allow increased testing concurrency, increased scale in the number of metrics recorded per test job (up to hundreds), and increased scale in the historical job information (up to many millions of jobs per VO).

  18. 76 FR 5277 - Revisions to the California State Implementation Plan, Santa Barbara Air Pollution Control...

    Science.gov (United States)

    2011-01-31

    ...EPA is taking direct final action to approve revisions to the Santa Barbara Air Pollution Control District (SBAPCD), Antelope Valley Air Quality Management District (AVAQMD), Ventura County Air Pollution Control District (VCAPCD) and Placer County Air Pollution Control District (PCAPCD) portion of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) emissions from gasoline bulk plants, terminals and vehicle dispensing facilities. We are approving local rules that regulate these emission sources under the Clean Air Act as amended in 1990 (CAA or the Act).

  19. 78 FR 21581 - Revisions to the California State Implementation Plan, Santa Barbara County Air Pollution Control...

    Science.gov (United States)

    2013-04-11

    ...EPA is proposing to approve revisions to the Santa Barbara County Air Pollution Control District (SBCAPCD) and South Coast Air Quality Management District (SCAQMD) portions of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) and oxides of nitrogen (NOX) emissions from gas-fired fan-type central furnaces, small water heaters, and the transfer and dispensing of gasoline. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act (CAA or the Act).

  20. Improved ATLAS HammerCloud Monitoring for local Site Administration

    CERN Document Server

    Boehler, Michael; The ATLAS collaboration; Hoenig, Friedrich; Legger, Federica; Sciacca, Francesco Giovanni; Mancinelli, Valentina

    2015-01-01

    Every day hundreds of tests are run on the Worldwide LHC Computing Grid for the ATLAS, and CMS experiments in order to evaluate the performance and reliability of the different computing sites. All this activity is steered, controlled, and monitored by the HammerCloud testing infrastructure. Sites with failing functionality tests are auto-excluded from the ATLAS computing grid, therefore it is essential to provide a detailed and well organized web interface for the local site administrators such that they can easily spot and promptly solve site issues. Additional functionality has been developed to extract and visualize the most relevant information. The site administrators can now be pointed easily to major site issues which lead to site blacklisting as well as possible minor issues that are usually not conspicuous enough to warrant the blacklisting of a specific site, but can still cause undesired effects such as a non-negligible job failure rate. This paper summarizes the different developments and optimiz...

  1. Improved ATLAS HammerCloud Monitoring for local Site Administration

    CERN Document Server

    Boehler, Michael; The ATLAS collaboration; Hoenig, Friedrich; Legger, Federica

    2015-01-01

    Every day hundreds of tests are run on the Worldwide LHC Computing Grid for the ATLAS, CMS, and LHCb experiments in order to evaluate the performance and reliability of the different computing sites. All this activity is steered, controlled, and monitored by the HammerCloud testing infrastructure. Sites with failing functionality tests are auto-excluded from the ATLAS computing grid, therefore it is essential to provide a detailed and well organized web interface for the local site administrators such that they can easily spot and promptly solve site issues. Additional functionalities have been developed to extract and visualize the most relevant information. The site administrators can now be pointed easily to major site issues which lead to site blacklisting as well as possible minor issues that are usually not conspicuous enough to warrant the blacklisting of a specific site, but can still cause undesired effects such as a non-negligible job failure rate. This contribution summarizes the different developm...

  2. HammerCloud: A Stress Testing System for Distributed Analysis

    CERN Document Server

    van der Ster, Daniel C; Ubeda Garcia, Mario; Paladin, Massimo

    2011-01-01

    Distributed analysis of LHC data is an I/O-intensive activity which places large demands on the internal network, storage, and local disks at remote computing facilities. Commissioning and maintaining a site to provide an efficient distributed analysis service is therefore a challenge which can be aided by tools to help evaluate a variety of infrastructure designs and configurations. HammerCloud (HC) is one such tool; it is a stress testing service which is used by central operations teams, regional coordinators, and local site admins to (a) submit arbitrary number of analysis jobs to a number of sites, (b) maintain at a steady-state a predefined number of jobs running at the sites under test, (c) produce web-based reports summarizing the efficiency and performance of the sites under test, and (d) present a web-interface for historical test results to both evaluate progress and compare sites. HC was built around the distributed analysis framework Ganga, exploiting its API for grid job management. HC has been ...

  3. Functional design criteria for the Hazardous Materials Management and Emergency Response (HAMMER) Training Center. Revision 1

    International Nuclear Information System (INIS)

    Sato, P.K.

    1995-01-01

    Within the United States, there are few hands-on training centers capable of providing integrated technical training within a practical application environment. Currently, there are no training facilities that offer both radioactive and chemical hazardous response training. There are no hands-on training centers that provide training for both hazardous material operations and emergency response that also operate as a partnership between organized labor, state agencies, tribes, and local emergency responders within the US Department of Energy (DOE) complex. Available facilities appear grossly inadequate for training the thousands of people at Hanford, and throughout the Pacific Northwest, who are required to qualify under nationally-mandated requirements. It is estimated that 4,000 workers at the Hanford Site alone need hands-on training. Throughout the Pacific Northwest, the potential target audience would be over 30,000 public sector emergency response personnel, as well as another 10,000 clean-up workers represented by organized labor. The HAMMER Training Center will be an interagency-sponsored training center. It will be designed, built, and operated to ensure that clean-up workers, fire fighters, and public sector management and emergency response personnel are trained to handle accidental spills of hazardous materials. Training will cover wastes at clean-up sites, and in jurisdictions along the transportation corridors, to effectively protect human life, property, and the environment

  4. Benchmarks solutions of the coupled systems NJOY/AMPX-II/HAMMER-TECHNION and the library JENDL-3

    International Nuclear Information System (INIS)

    Santos, A. dos

    1991-01-01

    Benchmarks calculations were performed with the newest released japanese nuclear data library JENDL-3. The calculations were performed with the methodology developed at IPEN/CNEN-SP based on a coupled NJOY/AMPX-II/HAMMER-TECHNION system. The analyses show that the long-standing problem of the overprediction of the epithermal U-238 neutron capture still remains. Besides that there is an indication that the fission cross section of U-238 might be underestimated. (author)

  5. The Effects of Bit Wear on Respirable Silica Dust, Noise and Productivity: A Hammer Drill Bench Study.

    Science.gov (United States)

    Carty, Paul; Cooper, Michael R; Barr, Alan; Neitzel, Richard L; Balmes, John; Rempel, David

    2017-07-01

    Hammer drills are used extensively in commercial construction for drilling into concrete for tasks including rebar installation for structural upgrades and anchor bolt installation. This drilling task can expose workers to respirable silica dust and noise. The aim of this pilot study was to evaluate the effects of bit wear on respirable silica dust, noise, and drilling productivity. Test bits were worn to three states by drilling consecutive holes to different cumulative drilling depths: 0, 780, and 1560 cm. Each state of bit wear was evaluated by three trials (nine trials total). For each trial, an automated laboratory test bench system drilled 41 holes 1.3 cm diameter, and 10 cm deep into concrete block at a rate of one hole per minute using a commercially available hammer drill and masonry bits. During each trial, dust was continuously captured by two respirable and one inhalable sampling trains and noise was sampled with a noise dosimeter. The room was thoroughly cleaned between trials. When comparing results for the sharp (0 cm) versus dull bit (1560 cm), the mean respirable silica increased from 0.41 to 0.74 mg m-3 in sampler 1 (P = 0.012) and from 0.41 to 0.89 mg m-3 in sampler 2 (P = 0.024); levels above the NIOSH recommended exposure limit of 0.05 mg m-3. Likewise, mean noise levels increased from 112.8 to 114.4 dBA (P < 0.00001). Drilling productivity declined with increasing wear from 10.16 to 7.76 mm s-1 (P < 0.00001). Increasing bit wear was associated with increasing respirable silica dust and noise and reduced drilling productivity. The levels of dust and noise produced by these experimental conditions would require dust capture, hearing protection, and possibly respiratory protection. The findings support the adoption of a bit replacement program by construction contractors. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  6. Submarine landslides in the Santa Barbara Channel as potential tsunami sources

    Directory of Open Access Journals (Sweden)

    H. G. Greene

    2006-01-01

    Full Text Available Recent investigations using the Monterey Bay Aquarium Research Institutes (MBARI Remotely Operated Vehicles (ROVs 'Ventana' and 'Tiburon' and interpretation of MBARI's EM 300 30 kHz multibeam bathymetric data show that the northern flank of the Santa Barbara Basin has experienced massive slope failures. Of particular concern is the large (130 km2 Goleta landslide complex located off Coal Oil Point near the town of Goleta, that measures 14.6-km long extending from a depth of 90 m to nearly 574 m deep and is 10.5 km wide. We estimate that approximately 1.75 km3 has been displaced by this slide during the Holocene. This feature is a complex compound submarine landslide that contains both surfical slump blocks and mud flows in three distinct segments. Each segment is composed of a distinct head scarp, down-dropped head block and a slide debris lobe. The debris lobes exhibit hummocky topography in the central areas that appear to result from compression during down slope movement. The toes of the western and eastern lobes are well defined in the multibeam image, whereas the toe of the central lobe is less distinct. Continuous seismic reflection profiles show that many buried slide debris lobes exist and comparison of the deformed reflectors with ODP Drill Site 149, Hole 893 suggest that at least 200 000 years of failure have occurred in the area (Fisher et al., 2005a. Based on our interpretation of the multibeam bathymetry and seismic reflection profiles we modeled the potential tsunami that may have been produced from one of the three surfical lobes of the Goleta slide. This model shows that a 10 m high wave could have run ashore along the cliffs of the Goleta shoreline. Several other smaller (2 km2 and 4 km2 slides are located on the northern flank of the Santa Barbara Basin, both to the west and east of Goleta slide and on the Conception fan along the western flank of the basin. One slide, named the Gaviota slide, is 3.8 km2, 2.6 km long and 1

  7. 78 FR 21542 - Revisions to the California State Implementation Plan, Santa Barbara County Air Pollution Control...

    Science.gov (United States)

    2013-04-11

    ...EPA is taking direct final action to approve revisions to the Santa Barbara County Air Pollution Control District (SBCAPCD) and South Coast Air Quality Management District (SCAQMD) portions of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) and oxides of nitrogen (NOX) emissions from gas-fired fan-type central furnaces, small water heaters, and the transfer and dispensing of gasoline. We are approving local rules that regulate these emission sources under the Clean Air Act (CAA or the Act).

  8. Bathymetry and acoustic backscatter-outer mainland shelf, eastern Santa Barbara Channel, California

    Science.gov (United States)

    Dartnell, Peter; Finlayson, David P.; Ritchie, Andrew C.; Cochrane, Guy R.; Erdey, Mercedes D.

    2012-01-01

    In 2010 and 2011, scientists from the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), acquired bathymetry and acoustic-backscatter data from the outer shelf region of the eastern Santa Barbara Channel, California. These surveys were conducted in cooperation with the Bureau of Ocean Energy Management (BOEM). BOEM is interested in maps of hard-bottom substrates, particularly natural outcrops that support reef communities in areas near oil and gas extraction activity. The surveys were conducted using the USGS R/V Parke Snavely, outfitted with an interferometric sidescan sonar for swath mapping and real-time kinematic navigation equipment. This report provides the bathymetry and backscatter data acquired during these surveys in several formats, a summary of the mapping mission, maps of bathymetry and backscatter, and Federal Geographic Data Committee (FGDC) metadata.

  9. First attempt to study rock glaciers in New Zealand using the Schmidt-hammer - framework and preliminary results

    Science.gov (United States)

    Winkler, Stefan; Lambiel, Christophe; Sattler, Katrin; Büche, Thomas; Springer, Johanna

    2016-04-01

    Although not uncommon within the dryer eastern parts of the Southern Alps, New Zealand, comparatively few previous studies have previously focused on rock glacier dynamics and spatial distribution. Neither investigations of their chronological constraints nor any studies on actual rock glacier velocities have yet been carried out. Rock glaciers and periglacial processes still largely constitute a largely unexplored albeit potentially valuable field of research in the Southern Alps. The high-altitude valley head of Irishman Stream in the Ben Ohau Range between Lakes Ohau and Pukaki, roughly 30 km southeast of the Main Divide, contains a few morphologically intact rock glaciers and some appear to be active features (Sattler et al. 2016). Previous work focusing on the Late-glacial and early Holocene moraines in the valley head below the rock glaciers (Kaplan et al. 2010) provided 10Be-ages that could be utilised as fixed points for SHD (Schmidt-hammer exposure-age dating). Apart from detailed Schmidt-hammer sampling on the Late-glacial and early Holocene moraines, two altitudinal transects from the toe to their apex have been measured in detail on selected rock glaciers. On each of the multiple ridges of the rock glacier surface three sites of 50 boulders have been sampled with one impact each by the hammer (an N-type electronic SilverSchmidt by Proceq). Apart from getting some age constraints of these periglacial features in comparison to the well-dated moraines, the Schmidt-hammer measurements also had the aim to provide some insight into their genetic development resulting in a quite complex morphology of the rock glaciers and partial interaction with some of the moraines. Both altitudinal transects reveal a clear and continuous trend of increasing means (i.e. less weathered/younger exposure ages) towards their apex. The values for the individual ridges show, however, a transitional character with adjacent ridges albeit the abovementioned trend not statistically

  10. Transmutation analysis considering and explicit fission product treatment based on a coupled Hammer-Technion and Cinder-2 system

    International Nuclear Information System (INIS)

    Abe, A.Y.

    1989-01-01

    This work presents a study about neutron absorption in a typical PWR cell by considering an explicit treatment for the fission products. The proposed methodology to treat fission product neutron absorption in a lattice calculation combines the HAMMER-TECHNION and CINDER-2 codes. The fission product chain treatment considers nearly 99% of all original CINDER-2 neutron absorption chain treatment. Parallel to the explicit treatment, a cross section library in the HAMMER-TECHNION code multigroup structure for the fission products was generated using the ENDF/B-V fission product library and processed by NJOY and AMPX-II processing codes. The methodology validation was investigated against two available benchmarks and it was obtained excellent results for the K-Infinity (IAEA-TECDOC-233) as function of burnup and enrichment and for the aggregate quantity sup(σ)2200 in units of barns/fission cross sections (OKAZAKI and SOKOLOWSKI). This work contributed for a better understanding of the fission product neutron absorption in a typical PWR cell and showed that the explicit fission product treatment can be successfully achieved. Besides that the performance of the ENDF/B-V fission product library was accessed. (author)

  11. Development of a system of programs HAMMER - ORIGEN - 2 system

    International Nuclear Information System (INIS)

    Guimaraes, L.N.F.

    1984-07-01

    The development of a system of programs (Hamor-2) to calculate precision inventory of LWR reactors is presented. The Hamor-2 code generates with the Hammer-technion code the four (4) energy groupe effective cross section of the actinides: U-235, U-236, U-238, Pu-239, Pu-240, Pu-241, Pu-242. Hamor-2 collapses the four group energy effective cross section to one group energy effective cross section. Hamor-2 calculates with origen-2 the new concentrations for the actinides using the one group energy effective cross section. Two PWR reactors were analised. (HBR, KWO). The discrepancy between the final actinides conentration results calculated by Hamor-2 and the results of measures finded in the references were calculated. That discrepancies have been compared with the discrepancy between : the final actinide concentration results calculated by Origen-2 and some measured results finded in the references. (E.G.) [pt

  12. Prevention of water hammers behind fast acting shut-off valves

    International Nuclear Information System (INIS)

    Dudlik, A.; Schlueter, S.; Prasser, H.M.

    1999-01-01

    Shut-off valves are often applied for a quick safety shut-down of pipelines for dangerous liquids. When the valve is suddenly closed at a certain flow rate, the pressure behind the valve decreases due to the momentum of the liquid. This leads to an evaporation and to a formation of a cavitation bubble if the resulting minimum pressure becomes lower than the saturation pressure at the given temperature. This type of water hammer was studied at a test facility of Fraunhofer UMSICHT in Oberhausen. The task of FZR was the development of an adequate two-phase flow instrumentation to visualise the cavitation phenomenon. During the project unique digital movie sequences of appearing and condensing cavitation bubbles were recorded, that gave valuable insights into the transient process. In the result, a new method was found to prevent the collapse of the cavitation bubbles and to avoid the corresponding pressure peaks. (orig.)

  13. Structural dynamics and fracture mechanics calculations of the behaviour of a DN 425 test piping system subjected to transient loading by water hammer

    International Nuclear Information System (INIS)

    Kussmaul, K.; Kobes, E.; Diem, H.; Schrammel, D.; Brosi, S.

    1994-01-01

    Within the scope of the German HDR safety programme, several tests were carried out to investigate transient pipe loading initiated by a simulated double-ended guillotine break event, and subsequent closure of a feedwater check valve (water hammer, blow-down). Numerical analyses by means of finite element programmes were performed in parallel to the experiments. Using water hammer tests of a DN 425 piping system with predamaged components, the procedure of such analyses will be demonstrated. The results are presented, beginning with structural dynamic calculations of the undamaged piping; followed by coupling of structural dynamics and fracture mechanics computations with simple flaw elements (line spring); and finishing with costly three-dimensional fracture mechanics analyses. A good description of the real piping behaviour can be made by the numerical methods, even in the case of high plastification processes. ((orig.))

  14. Hypothenar hammer syndrome in sports.

    Science.gov (United States)

    Müller, L P; Rudig, L; Kreitner, K F; Degreif, J

    1996-01-01

    Repetitive blunt trauma or single severe trauma to the hypothenar region may lead to traumatic thrombosis of the distal ulnar artery (hypothenar hammer syndrome, HHS). In the sports-related literature we found and analysed isolated cases attributed to injuries sustained during sporting activities such as baseball, badminton, handball, football, frisbee, softball, karate, weight-lifting and hockey. Further, we report the case of an amateur golf player with ischaemic symptoms of his left hand, where angiography revealed filling defects in the digital arteries associated with a corkscrew-like configuration of the distal ulnar artery. Magnetic resonance imaging (MRI) scan demonstrated, at the level of the hamulus ossis hamati, accessory fibres of m. palmaris brevis forming a sling around the ulnar artery. Treatment by resection of the thrombosed a. ulnaris segment and replacement with an autologous vein graft resulted in complete relief of symptoms. Histological sections revealed partially organized thrombi adherent to the intimal surface with fragmentation of the internal elastic membrane, indicating a traumatic genesis. As the mechanism of injury, we suspected intensive golf playing with the grip style and subsequent motions leading to pressure injury of the hypothenar area and the underlying ulnar artery. Contraction of the anomalous muscle belly may have additionally compressed the artery, slowing down the arterial flow and promoting thrombosis. In most reported cases including our own, it took a relatively long time until the cause of the disease as traumatic was found and accepted. The initial repetitive blunt or single severe trauma initiating the HHS can easily be overlooked or ignored. After intimal damage of a. ulnaris, the beginning of symptoms may be prolonged and mislead one into thinking the cause is a collagen or vasospastic disease.

  15. Homologous series of induced early mutants in indican rice. Pt.1. The production of homologous series of early mutants

    International Nuclear Information System (INIS)

    Chen Xiulan; Yang Hefeng; He Zhentian; Han Yuepeng; Liu Xueyu

    1999-01-01

    The percentage of homologous series of early mutants induced from the same Indican rice variety were almost the same (1.37%∼1.64%) in 1983∼1993, but the ones from the different eco-typical varieties were different. The early variety was 0.73%, the mid variety was 1.51%, and the late variety was 1.97%. The percentage of homologous series of early mutants from the varieties with the same pedigree and relationship were similar, but the one from the cog nation were lower than those from distant varieties. There are basic laws and characters in the homologous series of early mutants: 1. The inhibited phenotype is the basic of the homologous series of early mutants; 2. The production of the homologous series of early mutants is closely related with the growing period of the parent; 3. The parallel mutation of the stem and leaves are simultaneously happened with the variation of early or late maturing; 4. The occurrence of the homologous series of early mutants is in a state of imbalance. According to the law of parallel variability, the production of homologous series of early mutants can be predicted as long as the parents' classification of plant, pedigree and ecological type are identified. Therefore, the early breeding can be guided by the law of homologous series of early mutants

  16. Moralidade, autonomia e educação em Kant : uma leitura a partir de Barbara Herman

    OpenAIRE

    Fábio C. Ribeiro Mendes

    2013-01-01

    A educação é um tema geralmente considerado periférico à teoria moral de Kant. A presente pesquisa pretende apontar para a possibilidade não usual de uma leitura da filosofia moral kantiana, a partir das contribuições de Barbara Herman. Defende-se que é possível adotar a perspectiva da formação moral do agente concreto como uma maneira de compreender uma importante conexão entre os conceitos de moralidade, autonomia e educação. O primeiro passo é observar que a discussão em torno do valor do ...

  17. Computational models to determine fluid dynamical transients due to condensation induced water hammer (CIWH)

    International Nuclear Information System (INIS)

    Swidersky, H.; Schaffrath, A.; Dudlik, A.

    2011-01-01

    Condensation induced water hammer (CIWH) represent a dangerous phenomenon in pipings, which can endanger the pipe integrity. If they cannot be excluded, they have to be taken into account for the integrity proof of components and pipe structures. Up to now, there exists no substantiated model, which sufficiently determines loads due to CIWH. Within the framework of the research alliance CIWA, a tool for estimating the potential and the amount of pressure loads will be developed based on theoretical work and supported by experimental results. This first study discusses used computational models, compares their results against experimental observations and gives an outlook onto future techniques. (author)

  18. Application of image processing technology to problems in manuscript encapsulation. [Codex Hammer

    Science.gov (United States)

    Glackin, D. L.; Korsmo, E. P.

    1983-01-01

    The long term effects of encapsulation individual sheets of the Codex Hammer were investigated. The manuscript was simulated with similar sheets of paper which were photographed under repeatable raking light conditions to enhance their surface texture, encapsulated in plexiglas, cycled in an environmental test chamber, and rephotographed at selected intervals. The film images were digitized, contrast enhanced, geometrically registered, and apodized. An FFT analysis of a control sheet and two experimental sheets indicates no micro-burnishing, but reveals that the ""mesoscale'' deformations with sizes 8mm are degrading monotonically, which is of no concern. Difference image analysis indicates that the sheets were increasingly stressed with time and that the plexiglas did not provide a sufficient environmental barrier under the simulation conditions. The relationship of these results to the Codex itself is to be determined.

  19. Computational simulations of direct contact condensation as the driving force for water hammer

    International Nuclear Information System (INIS)

    Ceuca, Sabin-Cristian

    2015-01-01

    An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

  20. Computational simulations of direct contact condensation as the driving force for water hammer

    Energy Technology Data Exchange (ETDEWEB)

    Ceuca, Sabin-Cristian

    2015-04-27

    An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

  1. Determination of in-situ strength on selected bridge element concrete girder and slab of Nagtahan bridge using rebound hammer test

    International Nuclear Information System (INIS)

    Uy, Bernadette Betsy B.; Banaga, Renato T.

    2013-01-01

    This study examined the extent of the damage due to fire on the affected areas of the bridge structure. The need to assess the damage of the Nagtahan Bridge is very useful to provide appropriate measures in the repair or in the reinforcement of the bridge, hence will ensure its strength and integrity. The study included two (2) spans of the bridge deck/slab with specific locations of the bridge that were subjected for testing. The Rebound Hammer was used as a preliminary test in evaluating the bridge condition. Its capability is to assess the in-place uniformity of concrete, to delineate regions in a structure of poor quality or deteriorated concrete, and to estimate the in-place strength; and ultimately, for relative comparison between the different structures of the bridge. With the use of the NDT Rebound Hammer Test, the researchers were able to determine whether or not the in-situ strength of the bridge's concrete has been weakened due to fire. The DPW-Standard Specification is the government acceptable manual, containing the acceptance criteria, used as the basis for standard construction procedures in the department.(author)

  2. Ativismo artístico: engajamento político e questões de gênero na obra de Barbara Kruger Artistic activism: political awareness and gender issues in Barbara Kruger's work

    Directory of Open Access Journals (Sweden)

    Lina Alves Arruda

    2011-08-01

    Full Text Available O presente artigo introduz e contextualiza as primeiras manifestações feministas que compuseram o panorama artístico do final da década de 1960 até 1980. São analisadas as circunstâncias históricas (incluindo a história da arte que facilitaram a ponte entre as esferas da arte e da política, bem como os problemas formais e estéticos que a prática artística ativista apresentou e sua recepção como movimento. Para tanto, nos basearemos no trabalho da artista norte-americana Barbara Kruger, que produziu obras fundamentais para a consolidação da arte feminista, abordando criticamente uma ampla variedade de temas relacionados à mulher (violência, aborto, identidade, papel social, estética. O conteúdo das obras de Kruger está em sintonia com importantes circunstâncias políticas e temas sociais contemporâneos à sua produção e estabelece relação direta com teorias feministas da época, permitindo uma análise do contexto artístico e sócio-político do período.The present article introduces and contextualizes early feminist artworks which emerged in the late 1960's up to the 1980's. It analyzes the historical circumstances which linked the artistic and social spheres, as well as the aesthetic and formal problems that came along with the artistic activist practice and its reception as a movement. The analysis will be based on the work of the North-American artist Barbara Kruger, who has produced fundamental pieces which consolidate feminist art. Kruger's work has a critical approach towards a large variety of subjects regarding women (violence, abortion, identity, social roles, aesthetics. The content of her work is engaged with important social matters and with the political scene at the period of its production, and it also bears a direct relation with the feminist theories of that period, reasons which allow for an analysis of both the artistic and the social-political contexts.

  3. Visual analysis and Schmidt rebound hammer test of Taj-ul-Masajid

    Directory of Open Access Journals (Sweden)

    A. Hussain

    2017-09-01

    Full Text Available Taj-ul-Masajid, literally, the crown among mosques is an embodiment of genius structural engineering located in the heart of Madhya Pradesh, Bhopal. A unique combination of the Mughal Architecture in complete stone masonry and modern day RCC work, it is a liaison between the past and the present of structural engineering. A wonder in its own right, the structure is often neglected by technicians and conservationalists alike, a satire on their ingenuity. Now, in a severely dilapidated condition, the structure is in pressing need of structural rehabilitation. The authors intend to perform in-situ Non-Destructive Testing & Evaluation (NDT&E of this structure and thereby suggest steps to better its present condition. As a first step, they’ve performed the visual analysis and Schmidt Rebound Hammer Test on the concrete portion of the structure which has been presented herein. The authors have also suggested a new approach for the verification of results obtained.

  4. Experimental and theoretical study of steam condensation induced water hammer phenomena

    International Nuclear Information System (INIS)

    Barna, Imre Ferenc; Baranyai, Gabor; Ezsoel, Gyoergy

    2009-01-01

    We investigate steam condensation induced water hammer (waha) phenomena and present experimental and theoretical results. Some of the experiments were performed in the PMK-2 facility, which is a full-pressure thermohydraulic model of the nuclear power plant of VVER-440/312 type and located in the Atomic Energy Research Institute Budapest, Hungary. Other experiments were done in the ROSA facility in Japan. On the theoretical side waha is studied and analyzed with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to Relap5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. Experimentally measured and theoretically calculated waha pressure peaks are in qualitative agreement. (author)

  5. Improving ATLAS grid site reliability with functional tests using HammerCloud

    CERN Document Server

    Legger, F; The ATLAS collaboration

    2012-01-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2011, and more coming in 2012, distributed computing has become the established way to analyse collider data. The ATLAS grid infrastructure includes almost 100 sites worldwide, ranging from large national computing centers to smaller university clusters. These facilities are used for data reconstruction and simulation, which are centrally managed by the ATLAS production system, and for distributed user analysis. To ensure the smooth operation of such a complex system, regular tests of all sites are necessary to validate the site capability of successfully executing user and production jobs. We report on the development, optimization and results of an automated functional testing suite using the HammerCloud framework. Functional tests are short light-weight applications covering typical user analysis and production schemes, which are periodically submitted to all ATLAS grid sites. Results from those tests are collected and used to evaluate site...

  6. Improving ATLAS grid site reliability with functional tests using HammerCloud

    CERN Document Server

    Legger, F; The ATLAS collaboration; Medrano Llamas, R; Sciacca, G; Van der Ster, D C

    2012-01-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2011, and more coming in 2012, distributed computing has become the established way to analyse collider data. The ATLAS grid infrastructure includes more than 80 sites worldwide, ranging from large national computing centers to smaller university clusters. These facilities are used for data reconstruction and simulation, which are centrally managed by the ATLAS production system, and for distributed user analysis. To ensure the smooth operation of such a complex system, regular tests of all sites are necessary to validate the site capability of successfully executing user and production jobs. We report on the development, optimization and results of an automated functional testing suite using the HammerCloud framework. Functional tests are short light-weight applications covering typical user analysis and production schemes, which are periodically submitted to all ATLAS grid sites. Results from those tests are collected and used to evaluate si...

  7. A Conversation with Martin Stannard and Barbara Cooke

    Directory of Open Access Journals (Sweden)

    Annabel Williams

    2016-10-01

    Full Text Available Martin Stannard is Professor of Modern English Literature at the University of Leicester. He read for his first degree in English at Warwick (1967-70, before taking an MA at Sussex University, and a DPhil at Oxford. Professor Stannard’s two-volume literary biography of Evelyn Waugh (1986, 1992, and his biography of Muriel Spark (2009 are essential reading for Waugh and Spark scholars, and are each studies in the value of historical contextualisation for appreciating the literary oeuvre of a writer. Stannard’s 1995 Norton Critical Edition of Ford Madox Ford’s modernist novel, The Good Soldier, similarly brings context to bear through his rigorous textual editing, annotation and critical apparatus. Stannard is currently the Principal Investigator for the Complete Works of Evelyn Waugh project, which is supported by a grant of  £822,000 from the AHRC, and which will see Oxford University Press publish 43 scholarly edition volumes of Waugh – the first of which appears next year. This year marks the fiftieth anniversary of Waugh’s death. Dr Barbara Cooke also teaches at the School of English at the University of Leicester. She received a BA and MA from Warwick (dates, and a PhD in Creative and Critical writing from the University of East Anglia for her interdisciplinary thesis Oil Men: the Twinned Lives of Arnold Wilson and Morris Young. Dr. Cooke is Research Associate for the Complete Works of Evelyn Waugh, providing a vital link between the project's 23 editors, of which she is one, editing Waugh’s autobiography A Little Learning (1964.

  8. Hypothenar Hammer Syndrome Caused by Recreational Sports Activities and Muscle Anomaly in the Wrist

    International Nuclear Information System (INIS)

    Kreitner, Karl-Friedrich; Dueber, Christoph; Mueller, Lars-Peter; Degreif, Juergen

    1996-01-01

    A 34-year-old man with digital ischemia is reported. Angiography revealed thromboembolic occlusions of the proper digital arteries of the index, middle, and ring fingers and a tortuous ulnar artery in Guyon's canal. Though hypothenar hammer syndrome was suspected, there was no relevant occupational history. Magnetic resonance imaging and magnetic resonance angiography demonstrated an anomalous muscular sling around the ulnar artery immediately adjacent to the hook of the hamate. The ulnar artery showed mural thrombi in its tortuous segment. These findings were confirmed during operative exploration. After thrombectomy and embolectomy the involved segment of the ulnar artery was replaced by an autologous vein graft. Postoperatively there was complete resolution of the symptoms. Only during convalescence did it become clear that the patient was a passionate golfer

  9. Precipitation in Santa Barbara, CA on varying timescales and the relationships with the El Niño Southern Oscillation, the Madden-Julian Oscillation, and atmospheric rivers

    Science.gov (United States)

    Harris, S. M.; Carvalho, L. V.; Jones, C.

    2013-12-01

    This study aimed to understand the patterns and variations of extreme precipitation events that occur in Santa Barbara County and determine the relationships with various phenomena that affect the region. Santa Barbara, CA is an area with complex topography that is disposed to numerous hazard events including landslides and flooding, particularly during the region's rainy season (Nov.-Apr.). These incidents are especially frequent in the seasons after fire-events, another hazard common to the region. In addition, Santa Barbara is affected by several tropical phenomena that influence precipitation on varying timescales including the El Niño Southern Oscillation (ENSO), the Madden-Julian Oscillation (MJO), and atmospheric rivers (ARs). It is well known that ENSO and the MJO influence storms that occur in southern California through processes such as the modulation of the upper level jet and the low level moisture flux. ARs have been revealed to be responsible for the movement of large quantities of water vapor from tropical areas to the midlatitudes and have been linked to high-intensity storms throughout the western coast of North America. We examined rainy season (Nov.-Apr.) precipitation within Santa Barbara County using hourly rainfall data spanning approximately forty years (~1971-2010) from seven, local, rain gauge stations. The distributions as well as totals of precipitation on varying timescales (hourly, daily, seasonal, and yearly) were defined for specified intensities of rainfall based upon the 75th, 90th, 95th, and 99th percentiles. Persistence, expressed as the number of consecutive hours (or days) including intense precipitation defined according to the percentiles, was investigated on the hourly and daily timescales. In addition, specified storm episodes identified in this study were examined with data from the Tropical Rainfall Measurement Mission in order to assess the spatial features of high-intensity storms. Results from this analysis will be

  10. Color management with a hammer: the B-spline fitter

    Science.gov (United States)

    Bell, Ian E.; Liu, Bonny H. P.

    2003-01-01

    To paraphrase Abraham Maslow: If the only tool you have is a hammer, every problem looks like a nail. We have a B-spline fitter customized for 3D color data, and many problems in color management can be solved with this tool. Whereas color devices were once modeled with extensive measurement, look-up tables and trilinear interpolation, recent improvements in hardware have made B-spline models an affordable alternative. Such device characterizations require fewer color measurements than piecewise linear models, and have uses beyond simple interpolation. A B-spline fitter, for example, can act as a filter to remove noise from measurements, leaving a model with guaranteed smoothness. Inversion of the device model can then be carried out consistently and efficiently, as the spline model is well behaved and its derivatives easily computed. Spline-based algorithms also exist for gamut mapping, the composition of maps, and the extrapolation of a gamut. Trilinear interpolation---a degree-one spline---can still be used after nonlinear spline smoothing for high-speed evaluation with robust convergence. Using data from several color devices, this paper examines the use of B-splines as a generic tool for modeling devices and mapping one gamut to another, and concludes with applications to high-dimensional and spectral data.

  11. Mateship and the Female Body in Barbara Baynton's “Squeaker's Mate”

    Directory of Open Access Journals (Sweden)

    Deborah Scheidt

    2015-01-01

    Full Text Available http://dx.doi.org/10.5007/2175-8026.2015v68n2p67 “Mateship”, or companionship and loyalty in adverse situations, was a common theme for late 19th century Australian short stories. Women are excluded from the practice of mateship and are not usually the protagonists of these narratives, being either kept in the background as mothers and housewives, or not present at all in the plots.  Going against these stereotypes, in Barbara Baynton’s story “Squeaker’s Mate”, the “mate” is an independent, strong and hard-working woman. Baynton explores the gloomy consequences of this reversal of expected gender roles, especially after an accident leaves the protagonist paralysed and no longer in control of her body. What occurs in “Squeaker’s Mate” is a kind of “anti-mateship”, where irony serves as a device to expose gender relations and the exclusion of women from what is traditionally considered heroic and historical. In “Squeaker’s Mate”, Baynton questioned the adoption of “mateship” as an Australian value more than half a century before that discussion started to draw formal critical attention.

  12. Two-dimensional fluid-hammer analysis by the method of nearcharacteristics

    International Nuclear Information System (INIS)

    Shin, Y.W.; Kot, C.A.

    1975-05-01

    A numerical technique based on the method of nearcharacteristics is considered for solving propagation of fluid-hammer waves in a two-dimensional geometry. The solution is constructed by relating flow conditions by compatibility equations along lines called nearcharacteristics. Three choices are considered in the numerical scheme that are accurate within an error of the order of magnitude of the time step. Since the nearcharacteristics lie in the coordinate planes, the technique provides an efficient method requiring only simple interpolations in the initial plane. On the other hand, the nearcharacteristics fall outside the characteristics cone. Thus the solution procedure directly refers to conditions outside the true domain of dependence. The effect of this is studied through numerical calculation of a simple example problem and comparison with results obtained by a bicharacteristic method. Comparison is also made with existing analytical solutions and experiments. Furthermore, the three solution schemes considered are examined for numerical stability by the vonNeumann test. Two of the schemes were found to be unstable; the third yielded a stability criterion equivalent to that of the bicharacteristic formulation. The stability-analysis results were confirmed by numerical experimentation. (auth)

  13. Multiple condensation induced water hammer events, experiments and theoretical investigations

    International Nuclear Information System (INIS)

    Barna, Imre Ferenc; Ezsoel, Gyoergy

    2011-01-01

    We investigate steam condensation induced water hammer (CIWH) phenomena and present experimental and theoretical results. Some of the experiments were performed in the PMK-2 facility, which is a full-pressure thermalhydraulic model of the nuclear power plant of VVER-440/312 type and located in the Atomic Energy Research Institute Budapest, Hungary. Other experiments were done in the ROSA facility in Japan. On the theoretical side CIWH is studied and analyzed with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shockcapturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to RELAP5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. New features are the existence of multiple, independent CIWH pressure peaks both in experiments and in simulations. Experimentally measured and theoretically calculated CIWH pressure peaks are in qualitative agreement. However, the computational results are very sensitive against flow velocity. (orig.)

  14. Hypothenar hammer syndrome: caused by a muscle anomaly? A case report with review of the literature.

    Science.gov (United States)

    Estermann, Lea; Ducommun, Pascal; Steurer-Dober, Isabelle; Hug, Urs

    2018-05-01

    The hypothenar hammer syndrome (HHS) is a rare entity of secondary Raynaud's phenomenon. The blunt hypothenar trauma causes a lesion of the vessel wall with a consecutive thrombosis or aneurysm of the ulnar artery at the Guyon's canal. Different risk factors are discussed such as nicotine abuse, or a muscle anomaly in the Guyon's canal. To date, there are five case reports published about muscle anomalies and HHS. We present a case of a 51-year-old shipbuilder with a unilateral HHS on his right dominant hand with a bilateral muscle anomaly. We successfully treated the patient by resection of the aneurysm without a resection of the atypical muscle.

  15. Experimental Study of Air Vessel Behavior for Energy Storage or System Protection in Water Hammer Events

    Directory of Open Access Journals (Sweden)

    Mohsen Besharat

    2017-01-01

    Full Text Available An experimental assessment of an air pocket (AP, confined in a compressed air vessel (CAV, has been investigated under several different water hammer (WH events to better define the use of protection devices or compressed air energy storage (CAES systems. This research focuses on the size of an AP within an air vessel and tries to describe how it affects important parameters of the system, i.e., the pressure in the pipe, stored pressure, flow velocity, displaced volume of water and water level in the CAV. Results present a specific range of air pockets based on a dimensionless parameter extractable for other real systems.

  16. Improving ATLAS grid site reliability with functional tests using HammerCloud

    Science.gov (United States)

    Elmsheuser, Johannes; Legger, Federica; Medrano Llamas, Ramon; Sciacca, Gianfranco; van der Ster, Dan

    2012-12-01

    With the exponential growth of LHC (Large Hadron Collider) data in 2011, and more coming in 2012, distributed computing has become the established way to analyse collider data. The ATLAS grid infrastructure includes almost 100 sites worldwide, ranging from large national computing centers to smaller university clusters. These facilities are used for data reconstruction and simulation, which are centrally managed by the ATLAS production system, and for distributed user analysis. To ensure the smooth operation of such a complex system, regular tests of all sites are necessary to validate the site capability of successfully executing user and production jobs. We report on the development, optimization and results of an automated functional testing suite using the HammerCloud framework. Functional tests are short lightweight applications covering typical user analysis and production schemes, which are periodically submitted to all ATLAS grid sites. Results from those tests are collected and used to evaluate site performances. Sites that fail or are unable to run the tests are automatically excluded from the PanDA brokerage system, therefore avoiding user or production jobs to be sent to problematic sites.

  17. A numerical analysis on the effect of inlet parameters for condensation induced water hammer

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Priyankan [Department of Mechanical Engineering, Jadavpur University, Kolkata (India); Chakravarty, Aranyak [Department of Mechanical Engineering, Jadavpur University, Kolkata (India); School of Nuclear Studies & Application, Jadavpur University, Kolkata (India); Ghosh, Koushik, E-mail: kghosh@mech.jdvu.ac.in [Department of Mechanical Engineering, Jadavpur University, Kolkata (India); Mukhopadhyay, Achintya; Sen, Swarnendu [Department of Mechanical Engineering, Jadavpur University, Kolkata (India); Dutta, Anu; Goyal, Priyanshu [Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai (India)

    2016-08-01

    Highlights: • Condensation induced water hammer phenomenon is analysed with RELAP5/Mod 3.4. • Effect of various inlet conditions on the occurrence of CIWH are investigated. • Pressure peak amplitude and location has strong dependency on water subcooling. • Superheated steam does not have significant impact on pressure amplitude. • Presence of dry saturated steam is the necessary condition for CIWH. - Abstract: Direct contact condensation (DCC) is almost an inevitable phenomenon during accidental condition for all LWRs. Rapid condensation caused by the direct contact of steam and subcooled water can lead to condensation induced water hammer (CIWH). The present work explores the underlying physics of CIWH phenomenon in a horizontal pipe under different inlet conditions such as inlet water temperature, pressure difference between steam and water section, steam superheating, steam quality and duration of valve opening using RELAP5/Mod 3.4. This work emphasises on the prediction of pressure peak magnitude in conjunction with its location of occurrence under different parametric conditions. The stratified to slug flow transition is presented in terms of the ‘flow regime map’ which is identified as the primary cause for pressure wave generation. The strongest pressure wave amplitude due to CIWH is found to be 116.6 bar for ΔP = 10 bar. Observation reveals that peak pressure location shifts towards the subcooled water injection point for higher inlet water temperature. For the lowest inlet water temperature (T{sub in} = 20 °C), the peak pressure is found at a distance of 47.5 cm away from the water inlet whereas, for the high water temperature (T{sub in} = 120 °C), peak pressure is observed at 6.25 cm away from the injection point. It is also observed that the duration of valve opening significantly affects the location of peak pressure occurrence. This study also reveals that the presence of superheated or wet steam could possibly avoid the occurrence of

  18. Biotic response to late Quaternary rapid climate switches in Santa Barbara Basin: Ecological and evolutionary implications

    International Nuclear Information System (INIS)

    Cannariato, K.G.; Kennett, J.P.; Behl, R.J.

    1999-01-01

    Benthic foraminiferal assemblages from Santa Barbara Basin exhibit major faunal and ecological switches associated with late Quaternary millennial- to decadal-scale global climate oscillations. Repeated turnovers of entire faunas occurred rapidly (<40--400 yr) without extinction or speciation in conjunction with Dansgaard-Oeschger shifts in thermohaline circulation, ventilation, and climate, confirming evolutionary model predictions of Roy et al. Consistent faunal successions of dysoxic taxa during successive interstadials reflect the extreme sensitivity and adaptation of the benthic ecosystem to the rapid environmental changes that marked the late Quaternary and possibly other transitional intervals in the history of the Earth's ocean-atmosphere-cryosphere system. These data support the hypothesis that broad segments of the biosphere are well adapted to rapid climate change

  19. Magnetic Field Emission Comparison for Series-Parallel and Series-Series Wireless Power Transfer to Vehicles – PART 1/2

    DEFF Research Database (Denmark)

    Batra, Tushar; Schaltz, Erik

    2014-01-01

    Resonant circuits of wireless power transfer system can be designed in four possible ways by placing the primary and secondary capacitor in a series or parallel order with respect to the corresponding inductor. The two topologies series-parallel and series-series under investigation have been...... already compared in terms of their output behavior (current or voltage source) and reflection of the secondary impedance on the primary side. In this paper it is shown that for the same power rating series-parallel topology emits lesser magnetic fields to the surroundings than its series...

  20. Test to Extract Soil Properties Using the Seismic HammerTM Active Seismic Source

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Rebekah F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Abbott, Robert E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    Geologic material properties are necessary parameters for ground motion modeling and are difficult and expensive to obtain via traditional methods. Alternative methods to estimate soil properties require a measurement of the ground's response to a force. A possible method of obtaining these measurements is active-source seismic surveys, but measurements of the ground response at the source must also be available. The potential of seismic sources to obtain soil properties is limited, however, by the repeatability of the source. Explosives, and hammer surveys are not repeatable because of variable ground coupling or swing strength. On the other hand, the Seismic Hammer TM (SH) is consistent in the amount of energy it inputs into the ground. In addition, it leaves large physical depressions as a result of ground compaction. The volume of ground compaction varies by location. Here, we hypothesize that physical depressions left in the earth by the SH correlate to energy recorded by nearby geophones, and therefore are a measurement of soil physical properties. Using measurements of the volume of shot holes, we compare the spatial distribution of the volume of ground compacted between the different shot locations. We then examine energy recorded by the nearest 50 geophones and compare the change in amplitude across hits at the same location. Finally, we use the percent difference between the energy recorded by the first and later hits at a location to test for a correlation to the volume of the shot depressions. We find that: * Ground compaction at the shot-depression does cluster geographically, but does not correlate to known surface features. * Energy recorded by nearby geophones reflects ground refusal after several hits. * There is no correlation to shot volume and changes in energy at particular shot locations. Deeper material properties (i.e. below the depth of surface compaction) may be contributing to the changes in energy propagation. * Without further

  1. Modeling of Comparative Performance of Asphalt Concrete under Hammer, Gyratory, and Roller Compaction

    Directory of Open Access Journals (Sweden)

    Saad I. Sarsam

    2016-11-01

    Full Text Available The main objective of this study is to develop predictive models using SPSS software (version 18 for Marshall Test results of asphalt mixtures compacted by Hammer, Gyratory, and Roller compaction. Bulk density of (2.351 gm/cc, at OAC of (4.7 % was obtained as a benchmark after using Marshall Compactor as laboratory compactive effort with 75-blows. Same density was achieved by Roller and Gyratory Compactors using its mix designed methods. A total of (75 specimens, for Marshall, Gyratory, and Roller Compactors have been prepared, based on OAC of (4.7 % with an additional asphalt contents of more and less than (0.5 % from the optimum value. All specimens have been subjected to Marshall Test. Mathematical models obtained indicated that variation of Marshall Stiffness is based on the variation of air voids. All of these models depend on asphalt cement content too.

  2. 3. Similarities Across the Centuries: A Comparison Between Two Vocal Works by Barbara Strozzi and Peter Maxwell Davies

    Directory of Open Access Journals (Sweden)

    Marisi Rossella

    2018-03-01

    Full Text Available Musical creativity may be expressed by composers in diverse ways: sometimes they compose fully original works, which are characterized by specific features making them unique. Other times, musicians may feel a particular affinity with colleagues who lived centuries before, or identify peculiar resemblances between the time they live in, and a previous epoch, such as similar cultural climate and approach to life: in these cases, composers may author pieces which show surprising similarities with those of some predecessors. The present study compares a work of the seventeenth century, composed by Barbara Strozzi, and one composed in the 1960s by Peter Maxwell Davies, highlighting their similarities.

  3. Time Series Imputation via L1 Norm-Based Singular Spectrum Analysis

    Science.gov (United States)

    Kalantari, Mahdi; Yarmohammadi, Masoud; Hassani, Hossein; Silva, Emmanuel Sirimal

    Missing values in time series data is a well-known and important problem which many researchers have studied extensively in various fields. In this paper, a new nonparametric approach for missing value imputation in time series is proposed. The main novelty of this research is applying the L1 norm-based version of Singular Spectrum Analysis (SSA), namely L1-SSA which is robust against outliers. The performance of the new imputation method has been compared with many other established methods. The comparison is done by applying them to various real and simulated time series. The obtained results confirm that the SSA-based methods, especially L1-SSA can provide better imputation in comparison to other methods.

  4. Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

    Science.gov (United States)

    Keramat, A.; Tijsseling, A. S.; Hou, Q.; Ahmadi, A.

    2012-01-01

    Fluid-structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using the Kelvin-Voigt mechanical model. The equations are solved by two different approaches, namely the Method of Characteristics-Finite Element Method (MOC-FEM) and full MOC. In both approaches two important effects of FSI in fluid-filled pipes, namely Poisson and junction coupling, are taken into account. The study proposes a more comprehensive model for studying fluid transients in pipelines as compared to previous works, which take into account either FSI or viscoelasticity. To verify the proposed mathematical model and its numerical solutions, the following problems are investigated: axial vibration of a viscoelastic bar subjected to a step uniaxial loading, FSI in an elastic pipe, and hydraulic transients in a pressurised polyethylene pipe without FSI. The results of each case are checked with available exact and experimental results. Then, to study the simultaneous effects of FSI and viscoelasticity, which is the new element of the present research, one problem is solved by the two different numerical approaches. Both numerical methods give the same results, thus confirming the correctness of the solutions.

  5. Novel series of 1,2,4-trioxane derivatives as antimalarial agents.

    Science.gov (United States)

    Rudrapal, Mithun; Chetia, Dipak; Singh, Vineeta

    2017-12-01

    Among three series of 1,2,4-trioxane derivatives, five compounds showed good in vitro antimalarial activity, three compounds of which exhibited better activity against P. falciparum resistant (RKL9) strain than the sensitive (3D7) one. Two best compounds were one from aryl series and the other from heteroaryl series with IC 50 values of 1.24 µM and 1.24 µM and 1.06 µM and 1.17 µM, against sensitive and resistant strains, respectively. Further, trioxane derivatives exhibited good binding affinity for the P. falciparum cysteine protease falcipain 2 receptor (PDB id: 3BPF) with well defined drug-like and pharmacokinetic properties based on Lipinski's rule of five with additional physicochemical and ADMET parameters. In view of having antimalarial potential, 1,2,4-trioxane derivative(s) reported herein may be useful as novel antimalarial lead(s) in the discovery and development of future antimalarial drug candidates as P. falciparum falcipain 2 inhibitors against resistant malaria.

  6. Evaluation of LLTR Series II tests A-1A and A-1B test results

    International Nuclear Information System (INIS)

    Shoopak, B.F.; Amos, J.C.; Norvell, T.J.

    1980-03-01

    The standard methodology, with minor modifications provides conservative yet realistic predictions of leaksite and other sodium system pressures in the LLTR Series II vessel and piping. The good agreement between predicted and measured pressures indicates that the TRANSWRAP/RELAP modeling developed from the Series I tests is applicable to larger scale units prototypical of the Clinch River steam generator design. Calculated sodium system pressures are sensitive to several modeling parameters including rupture disc modeling, acoustic velocity in the test vessel, and flow rate from the rupture tube. The acoustic velocity which produced best agreement with leaksite pressures was calculated based on the shroud diameter and shroud wall thickness. The corresponding rupture tube discharge coefficient was that of the standard design methodology developed from Series I testing. As found in Series I testing, the Series II data suggests that the leading edge of the flow in the relief line is two phase for a single, doubled-ended guillotine tube rupture. The steam generator shroud acts as if it is relatively transparent to the transmission of radial pressures to the vessel wall. Slightly lower sodium system maximum pressures measured during Test A-1b compared to Test A-1a are attributed to premature failure (failure at a lower pressure) of the rupture disc in contact with the sodium for test A-1b. The delay in failure of the second disc in Test A-1b, which was successfully modeled with TRANSWRAP, is attributed to the limited energy in the nitrogen injection

  7. The NCAA's New Hammer

    Science.gov (United States)

    Wolverton, Brad

    2012-01-01

    A series of unprecedented scandals has eroded confidence in big-time sports, increasing the appetite for change. Some critics have a tough time seeing the NCAA as a savior; they say the real problem is the NCAA structure itself, which allows athletes to generate billions of dollars for colleges while earning no compensation themselves. Mark A.…

  8. HDR-investigations of check valve closure and resultant water hammer effects

    International Nuclear Information System (INIS)

    Scholl, K.D.

    1983-01-01

    The presented investigations are based on the Loss of Coolant Accident (LOCA). They concentrate on the first blowdown phase after pipe break of a feedwater line. The effect of such a break is moderated by quick closing check valves, by which the loss of coolant water is reduced and optimal post accident conditions are obtained. Unfortunately the closure of the valve can cause high pressure peaks (water hammer effects) in the feedwater system which potentially could produce safety relevant secondary damage. The system loading by these effects has been analysed. The HDR-Investigation-results led to an improvement of the feedwater system safety by verifying damping measures of quick closing check valves. Pressure peaks obtained with undamped valves in the range of 300 bars, are reduced to zero or a few bars above the normal operation pressure in feedwater systems. For the analytical simulation of valve closure the following dominant acting forces are identified: the blowdown flow resistance of the valve cone and the damping pistong force. The analytical description and quantification of the forces depends on blowdown flow and valve friction parameters. These have been evaluated and are presented for practical use. (orig.)

  9. Cavitating flow during water hammer using a generalized interface vaporous cavitation model

    Science.gov (United States)

    Sadafi, Mohamadhosein; Riasi, Alireza; Nourbakhsh, Seyed Ahmad

    2012-10-01

    In a transient flow simulation, column separation may occur when the calculated pressure head decreases to the saturated vapor pressure head in a computational grid. Abrupt valve closure or pump failure can result in a fast transient flow with column separation, potentially causing problems such as pipe failure, hydraulic equipment damage, cavitation or corrosion. This paper reports a numerical study of water hammer with column separation in a simple reservoir-pipeline-valve system and pumping station. The governing equations for two-phase transient flow in pipes are solved based on the method of characteristics (MOC) using a generalized interface vaporous cavitating model (GIVCM). The numerical results were compared with the experimental data for validation purposes, and the comparison indicated that the GIVCM describes the experimental results more accurately than the discrete vapor cavity model (DVCM). In particular, the GIVCM correlated better with the experimental data than the DVCM in terms of timing and pressure magnitude. The effects of geometric and hydraulic parameters on flow behavior in a pumping station with column separation were also investigated in this study.

  10. A time series model: First-order integer-valued autoregressive (INAR(1))

    Science.gov (United States)

    Simarmata, D. M.; Novkaniza, F.; Widyaningsih, Y.

    2017-07-01

    Nonnegative integer-valued time series arises in many applications. A time series model: first-order Integer-valued AutoRegressive (INAR(1)) is constructed by binomial thinning operator to model nonnegative integer-valued time series. INAR (1) depends on one period from the process before. The parameter of the model can be estimated by Conditional Least Squares (CLS). Specification of INAR(1) is following the specification of (AR(1)). Forecasting in INAR(1) uses median or Bayesian forecasting methodology. Median forecasting methodology obtains integer s, which is cumulative density function (CDF) until s, is more than or equal to 0.5. Bayesian forecasting methodology forecasts h-step-ahead of generating the parameter of the model and parameter of innovation term using Adaptive Rejection Metropolis Sampling within Gibbs sampling (ARMS), then finding the least integer s, where CDF until s is more than or equal to u . u is a value taken from the Uniform(0,1) distribution. INAR(1) is applied on pneumonia case in Penjaringan, Jakarta Utara, January 2008 until April 2016 monthly.

  11. Variation of Modal Characteristics of Electrical Cabinet According to the Excitation Level in Impact Hammer Test

    International Nuclear Information System (INIS)

    Cho, Sung Gook; So, Gi Hwan; Kim, Doo Kie

    2010-01-01

    There are many electrical cabinets in nuclear power plants. Safety-related equipment is typically seismic qualified before installation. Seismic qualification of equipment is possible when identifying the accurate dynamic characteristics of the equipment. According to the nature of the cabinet, the dynamic characteristics of the electrical cabinet vary nonlinearly with excitation level. This study analyzed the nonlinear variation of the dynamic properties of an actual cabinet. For the purpose of this study, a seismic monitoring system cabinet was selected as a specimen. The impact hammer tests were conducted to identify a variation of the dynamic characteristics of the specimen by increasing the impulse level. Modal identification technique was used to extract the modal properties of the cabinet from the measurements

  12. Additional vibration investigations on the prestressed tie rods attaching the no.1 lives team line clamps to the concrete structures at Paluel-1

    International Nuclear Information System (INIS)

    Guihot, P.; Le Picard, J.P.

    1993-12-01

    This test report presents vibration analysis results obtained on the prestressed tie rods attaching the N. 1 live steam line clamps to the concrete structures of the PALUEL-1 unit. The purpose of these tests was to assess the feasibility of using a vibration analysis to determine the effective prestress level in the tie rods. The previous investigations performed with an impact hammer yielded no definite conclusions as to the feasibility of the method. The new series of tests, performed with a sinusoidal scanning electro-dynamic exciter, gave far more accurate results. However, the eigenfrequencies characterizing the tie rod tension level were not evidenced. It would consequently not seem possible to identify the tightening level by monitoring the first resonant frequency with the equipment installed. There are alternative solutions, such as keeping the same principle and substantially increasing the excitation levels, thereby precluding a head and foot restraint response from the tie rod, or using an ultrasonic method. (authors). 2 figs., 3 refs., 2 annexes

  13. Actualidad de la fenomenología: la fenomenología de la vida de Renaud Barbaras

    Directory of Open Access Journals (Sweden)

    Larisson, Mariana

    2009-04-01

    Full Text Available In recent years we have seen a resurgence of a number of concepts connected to the notion of life, as well as to the several problematic that have their origin in this notion. Such problematic have come to be fashionable in fields such as science, politics, culture or in recent developments in economics and technology. Against this historical background, philosophical reflection on the phenomenon of life has not been, however, undertaken. In this context, the appearance of a philosophical attempt that presents itself as a phenomenology of life is of immediate interest and relevance. Such is the work of Renaud Bárbaras entitled Introduction à une phénoménologie de la vie (2008. The following analysis focuses on this text and attempts to bring to light its great problematic and possible implications.En los últimos años hemos asistido al surgimiento de toda una serie de conceptos ligados a la noción de vida y a las problemáticas que de ella se derivan. Las mismas que, hoy en día, se encuentran en boga en ámbitos tan diversos como la ciencia, la política, la cultura o los nuevos desarrollos económicos y tecnológicos. Sin embargo, y con este contexto histórico de fondo, la reflexión filosófica sobre el fenómeno de la vida resta aún por hacerse. En este sentido, la aparición de una filosofía que se presenta a sí misma como una fenomenología de la vida cobra una actualidad e interés inusitados. Tal es el caso de la reciente obra de Renaud Barbaras Introduction à une phénoménologie de la vie (2008, de la que se ocupa el presente escrito, en el que intentaremos poner de relieve la problemática que el texto revela y sus posibles derivaciones.

  14. Sensitivity analysis using contribution to sample variance plot: Application to a water hammer model

    International Nuclear Information System (INIS)

    Tarantola, S.; Kopustinskas, V.; Bolado-Lavin, R.; Kaliatka, A.; Ušpuras, E.; Vaišnoras, M.

    2012-01-01

    This paper presents “contribution to sample variance plot”, a natural extension of the “contribution to the sample mean plot”, which is a graphical tool for global sensitivity analysis originally proposed by Sinclair. These graphical tools have a great potential to display graphically sensitivity information given a generic input sample and its related model realizations. The contribution to the sample variance can be obtained at no extra computational cost, i.e. from the same points used for deriving the contribution to the sample mean and/or scatter-plots. The proposed approach effectively instructs the analyst on how to achieve a targeted reduction of the variance, by operating on the extremes of the input parameters' ranges. The approach is tested against a known benchmark for sensitivity studies, the Ishigami test function, and a numerical model simulating the behaviour of a water hammer effect in a piping system.

  15. Hypothenar hammer syndrome from ice hockey stick-handling.

    Science.gov (United States)

    Zayed, Mohamed A; McDonald, Joey; Tittley, Jacques G

    2013-11-01

    Ulnar artery thrombosis and hypothenar hammer syndrome are rare vascular complications that could potentially occur with repeated blows or trauma to the hand. Although initially reported as an occupational hazard among laborers and craftsmen, it has been observed more recently among recreationalists and athletes. Until now, it has never been reported as a complication in ice hockey players. In this case report, a 26-year-old Canadian professional ice hockey player presented with acute dominant right hand paleness, coolness, and pain with hand use. The patient used a wooden hockey stick with a large knob of tape at the end of the handle, which he regularly gripped in the palm of his right hand to help with face-offs and general stick-handling. Sonographic evaluation demonstrated no arterial flow in the distal right ulnar artery distribution, and ulnar artery occlusion with no aneurysmal degeneration was confirmed by magnetic resonance angiogram. Intraarterial thrombolytic therapy was initiated, and subsequent serial angiograms demonstrated significant improvement in distal ulnar artery flow as well as recanalization of right hand deep palmar arch and digital arteries. The patient's symptoms resolved, and he was maintained on therapeutic anticoagulation for 3 months prior to returning to playing ice hockey professionally, but with a padded glove and no tape knob at the handle tip. This case highlights a unique presentation of hockey stick-handling causing ulnar artery thrombosis that was likely from repeated palmar hypothenar trauma. Appropriate diagnostic imaging, early intraarterial thrombolysis, and postoperative surveillance and follow-up were crucial for the successful outcome in this patient. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Tools of Thor - more than a hammer: An overview of some analysis methods for turbulence investigation

    Science.gov (United States)

    Haaland, Stein; Vaivads, Andris; Eriksson, Elin

    2016-04-01

    In the old Norse mythology Thor was a hammer-wielding god associated with thunder and lightning. THOR is also an acronym for Turbulence Heating ObserveR - a planned space mission dedicated to stydy space plasma turbulence. Whereas the mythological Thor did most of his work with a single tool, Mjølnir - his hammer, the modern version of THOR is far more versatile. The proposed THOR spacecraft comes with a comprehensive package of instruments to explore the energy dissipation and particle energization taking place in turbulent plasma environments. This paper presents a more detailed investigation of some of the analysis methods listed in the submitted THOR proposal. To demonstrate the methods, we have used data from existing spacecraft missions like Cluster and MMS to examine and compare single-spacecraft and multi-spacecraft methods to establish proper frames. The presented analysis methods are based on fundamental plasma laws, such as conservation of mass, momentum and energy and do not require any triangulation or gradients based on multiple spacecraft. Our experience based on Cluster and MMS results show that a well equipped single spacecraft platform, like the proposed THOR mission, very often provides better and less ambiguous results that a constellation of many spacecraft with less capable instrumentation. Limitations in underlying assumptions, such as planarity and linearity, as well as non-optimal spacecraft separation and configurations often limit the possibility to utilize multi-spacecraft methods. We also investigate the role of time resolution and dynamical range of the measurements used in the methods. Since the particle instruments onboard THOR will have a much better time resolution than existing magnetospheric satellite missions, we infer that THOR will be far better suited to resolve time evolution in plasma structures. This is of particular importance in the solar wind and magnetosheat, where frame velocities can be very high. With a larger

  17. Hatching phenology and voltinism of Heterocypris barbara (Crustacea: Ostracoda from Lampedusa (Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Valeria Rossi

    2013-04-01

    Full Text Available The persistence of crustacean populations in ephemeral ponds requires appropriate adaptations in life history strategies (e.g. in hatching phenology. Organisms take advantage of pond filling when it occurs and hedge their bets for the possibility to complete one or more life cycles or to produce resting stages that ensure that the population will not go extinct. We carried out laboratory experiments to investigate the dynamics of a sexual population of Heterocypris barbara from a vernal pool in Lampedusa Island (Sicily. Experimental organisms were obtained hydrating sediments from Aria Rossa temporary pond. Recruitment from resting eggs, voltinism, mean body size and sex ratio were observed in microcosms at different conductivities (high 2.0-2.7 mS cm-1, intermediate 1.0-1.1 mS cm-1 and low 0.5-0.6 mS cm-1. Microcosms were kept in laboratory controlled conditions: constant (24°C 12:12 L:D and 16°C 10:14 L:D photoperiod or fluctuating thermal regimes. The experiment lasted 7 months. Resting and non-resting egg production and up to a bivoltine life cycle were observed. Recruitment events from egg bank and voltinism varied by thermal regime and conductivity. A prolonged recruitment phase occurred in conditions that could be considered a proxy of a rainy season (16°C, 10:14 L:D and low conductivity or of long hydroperiods (spring thermal fluctuating regime and intermediate conductivity. At 24°C, age at reproduction of females from resting eggs almost doubled at low conductivity (in comparison with high conductivity. Low conductivity also reduced hatching time of resting eggs while it increased development time and age at maturity. In thermal fluctuating regime, degree-days to reproduction were about double than at constant 24°C. Males, observed in all microcosms, reached maturity faster and had a shorter life span than females. Males initially outnumbered females, but later in the experiments females became dominant. We also evaluated the

  18. Theoretical study of steam condensation induced water hammer phenomena in horizontal pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Barna, Imre Ferenc [Hungarian Academy of Sciences, Budapest (Hungary). Wigner Research Center; ELI-HU Nonprofit Kft., Szeged (Hungary); Pocsai, Mihaly Andras [Hungarian Academy of Sciences, Budapest (Hungary). Wigner Research Center; Pecs Univ. (Hungary). Inst. of Physics; Guba, Attila [Hungarian Academy of Sciences, Budapest (Hungary). Energy Research Center; Imre, Attila Rikard [Hungarian Academy of Sciences, Budapest (Hungary). Energy Research Center; Budapest University of Technology and Economics (Hungary). Dept. of Energy Engineering

    2015-11-15

    Steam condensation induced water hammer (CIWH) phenomena are investigated and new theoretical results are presented. We use the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to RELAP5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. This model was validated with different CIWH experiments which were performed in the PMK-2 facility, which is a full-pressure thermohydraulic model of the nuclear power plant of VVER-440/312 type in the Energy Research Center of the Hungarian Academy of Sciences and in the Rosa facility of the Japan Atomic Energy Agency. In our present study we show the first part of a planned large database which will give us the upper and lower flooding mass flow rates for various pipe geometries where CIWH can happen. Such a reliable database would be a great help for future reactor constructions and scheming.

  19. Theoretical study of steam condensation induced water hammer phenomena in horizontal pipelines

    International Nuclear Information System (INIS)

    Barna, Imre Ferenc; Pocsai, Mihaly Andras; Pecs Univ.; Guba, Attila; Imre, Attila Rikard; Budapest University of Technology and Economics

    2015-01-01

    Steam condensation induced water hammer (CIWH) phenomena are investigated and new theoretical results are presented. We use the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to RELAP5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. This model was validated with different CIWH experiments which were performed in the PMK-2 facility, which is a full-pressure thermohydraulic model of the nuclear power plant of VVER-440/312 type in the Energy Research Center of the Hungarian Academy of Sciences and in the Rosa facility of the Japan Atomic Energy Agency. In our present study we show the first part of a planned large database which will give us the upper and lower flooding mass flow rates for various pipe geometries where CIWH can happen. Such a reliable database would be a great help for future reactor constructions and scheming.

  20. Neutronic studies in the enrichment reduction of research reactor IEAR-1

    International Nuclear Information System (INIS)

    Maiorino, J.R.; Fanaro, L.C.B.; Mai, L.A.; Ferreira, P.S.B.; Garone, J.G.M.

    1987-01-01

    In the present work the codes used by the Reactor Physics Division of IPEN-CNEN-SP in calculations for plate-type reactors are described analyzing research reactor IEAR-1. The IAEA model problem for a plate-type reactor 10 MW with high, medium and low enrichment is solved through different methodologies now in use at the RTF/IPEN-CNEN-SP (HAMMER and HAMMER-TECH-CITATION and LEO4-2DBP-UM) looking into the calculation capability for high to low enrichment conversion within the contract held with the IAEA (BRA-4661). Finally, present reactor configuration calculations are compared with experimental measurements with the aim to validate the calculation method. (Author)

  1. Antiplasmodial activity of a series of 1,3,5-triazine-substituted polyamines

    OpenAIRE

    Klenke, Burkhard; Barrett, Michael P.; Brun, Reto; Gilbert, Ian H.

    2017-01-01

    Polyamine biosynthesis and function has been shown to be a good drug target in some parasitic protozoa and it is proposed that the pathway might also represent a target in the malaria parasite Plasmodium falciparum. A series of 1,3,5-triazine-substituted polyamine analogues were tested for activity against Plasmodium falciparum in vitro. The series showed activity against the parasites and were generally more active against the chloroquine-resistant line K1 than the chloroquine-susceptible li...

  2. Skull wounds linked with blunt trauma (hammer example). A report of two depressed skull fractures--elements of biomechanical explanation.

    Science.gov (United States)

    Delannoy, Yann; Becart, Anne; Colard, Thomas; Delille, Rémi; Tournel, Gilles; Hedouin, Valéry; Gosset, Didier

    2012-09-01

    The lesions of the skull following perforating traumas can create complex fractures. The blunt traumas can, according to the swiftness and the shape of the object used, create a depressed fracture. The authors describe through two clinical cases the lesional characteristic of the blunt traumas, perforating the skull using a hammer. In both cases the cranial lesions were very typical: they were geometrical, square shaped, of the same size than the tool (head and tip of the hammer). On the outer table of the skull, the edges of the wounds were sharp and regular. On the inner table, the edges of the wounds were beveled and irregular. The bony penetration in the depressed fracture results from a rupture of the outer table of the bone under tension, in periphery, by the bend of the bone to the impact (outbending) and then, from the inner table with comminuted bony fragmentation. Breeding on the fractures of the size and the shape of the blunt objects used is inconstant and differs, that it is the objects of flat surface or wide in opposition to those of small surface area. Fractures morphologies depend on one hand on these extrinsic factors and on the other hand, of intrinsic factors (structure of the bone). To identify them, we had previously conducted experimental work on cranial bone samples. The bone was submitted to a device for three-point bending. This work had shown properties of thickness and stiffness of the various areas of the vault. Our cases are consistent with these results and illustrate the variability of bone lesions according to region and mode of use of blunt weapons. Many studies have identified criteria for identification of the weapons and the assistance of digital and biomechanical models will be an invaluable contribution with this aim in the future. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. Water-containing derivative phases of the Srn+1FenO3n+1 series

    International Nuclear Information System (INIS)

    Lehtimaeki, M.; Hirasa, A.; Matvejeff, M.; Yamauchi, H.; Karppinen, M.

    2007-01-01

    The n=1, 2, 3 and ∞ members of the homologous series Sr n+1 Fe n O 3n+1 of layered iron oxides are investigated for their tendency to accept additional layers of water in their crystals. The phases possess a Ruddlesden-Popper-type SrO-(SrO-FeO 2 ) n crystal structure, where the n=∞ limit is nothing but the perovskite structure. It is revealed that the n=1, 2 and 3 phases readily accommodate one or two layers of water between adjacent SrO layers, whereas the n=∞ member which lacks the SrO-SrO double-layer unit remains intact in the presence of water. The speed of the water intercalation process is found to decrease with increasing n. Among the layered water derivatives, the n=2 phase with two water molecules per formula unit, i.e. Sr 3 Fe 2 O 7 .2H 2 O, was found to be most stable. - Graphical abstract: Water-containing derivative phases obtained from the homologous series of Sr n+1 Fe n O 3n+1 Ruddlesden-Popper phases through topotactic water intercalation

  4. Antimalarial activity of HIV-1 protease inhibitor in chromone series.

    Science.gov (United States)

    Lerdsirisuk, Pradith; Maicheen, Chirattikan; Ungwitayatorn, Jiraporn

    2014-12-01

    Increasing parasite resistance to nearly all available antimalarial drugs becomes a serious problem to human health and necessitates the need to continue the search for new effective drugs. Recent studies have shown that clinically utilized HIV-1 protease (HIV-1 PR) inhibitors can inhibit the in vitro and in vivo growth of Plasmodium falciparum. In this study, a series of chromone derivatives possessing HIV-1 PR inhibitory activity has been tested for antimalarial activity against P. falciparum (K1 multi-drug resistant strain). Chromone 15, the potent HIV-1 PR inhibitor (IC50=0.65μM), was found to be the most potent antimalarial compound with IC50=0.95μM while primaquine and tafenoquine showed IC50=2.41 and 1.95μM, respectively. Molecular docking study of chromone compounds against plasmepsin II, an aspartic protease enzyme important in hemoglobin degradation, revealed that chromone 15 exhibited the higher binding affinity (binding energy=-13.24kcal/mol) than the known PM II inhibitors. Thus, HIV-1 PR inhibitor in chromone series has the potential to be a new class of antimalarial agent. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. The Little Giant: The IBM Series/1 in Library Applications.

    Science.gov (United States)

    Hendricks, Donald D.; Manino, Glenn

    1987-01-01

    This description of the use of IBM Series/1 minicomputers to implement a library automation system includes discussion of current functions of the system, the system configuration, communications capabilities, software, and cost factors. (CLB)

  6. Reseña de Gaspar Aguilar, «La comedia segunda de Los agravios perdonados», ed. C. George Peale, Santa Barbara, University of California, Publications of «eHumanista», 2016, 128 pp., edición digital

    Directory of Open Access Journals (Sweden)

    Ariel Núñez Sepúlveda

    2017-11-01

    Full Text Available Reseña de Gaspar Aguilar, La comedia segunda de Los agravios perdonados, ed. C. George Peale, Santa Barbara, University of California, Publications of eHumanista, 2016, 128 pp., edición digital

  7. Time series data correction for the Chang'E-1 gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Zhang Liyan; Zou Yongliao; Liu Jianzhong; Liu Jianjun; Shen Ji; Mu Lingli; Ren Xin; Wen Weibin; Li Chunlai

    2011-01-01

    The main goal of the gamma-ray spectrometer (GRS) onboard Chang'E-1 (CE-1) is to acquire global maps of elemental abundances and their distributions on the moon, since such maps will significantly improve our understanding of lunar formation and evolution. To derive the elemental maps and enable research on lunar formation and evolution, raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray spectra. The data correction procedures for the CE-1 GRS time series data are thoroughly described. The processing procedures to create the time series gamma-ray spectra described here include channel processing, optimal data selection, energy calibration, gain correction, dead time correction, geometric correction, orbit altitude normalization, eliminating unusable data and galactic cosmic ray correction. Finally, descriptions are also given on data measurement uncertainties, which will help the interested scientists to understand and estimate various uncertainties associated with the above data processing. (research papers)

  8. Water hammer effect in the spiral case and penstock of Francis turbines

    Science.gov (United States)

    Pepa, D.; Ursoniu, C.; Gillich, R. N.; Campian, C. V.

    2017-01-01

    Sudden pressure increases in the penstock or spiral case of a hydraulic turbine are the effect of sudden flow variation that occur during transient processes of type opening / closing or load rejection of the hydro unit. The consequence of the pressure rise in the spiral case and penstock is the water hammer phenomenon, whose effects can be devastating in some cases, up to breaking pipes and calamities produced in the area. This paper aims to analyze the method of calculation of the maximum pressure values that might occur in load rejection situations to a hydraulic turbine, in spiral case and in penstock, conditioned by the limiting of the values of the over speed and measures of limiting the increase in pressure in conjunction with limiting the increase in speed in these specific processes. As an example, we studied and analyzed the situation of a hydroelectric power plant equipped with a 7.8 MW Francis turbine without pressure regulator and the inflow surge. The results of analytical calculation overlaid on the experimental measurements performed during the performance tests of the hydro unit lead to the conclusion that the calculation algorithm proposed has been chosen correctly and the 2-stage closing law of the wicket gate promoted in this case is effective in such situations.

  9. On Sums of Numerical Series and Fourier Series

    Science.gov (United States)

    Pavao, H. Germano; de Oliveira, E. Capelas

    2008-01-01

    We discuss a class of trigonometric functions whose corresponding Fourier series, on a conveniently chosen interval, can be used to calculate several numerical series. Particular cases are presented and two recent results involving numerical series are recovered. (Contains 1 note.)

  10. Emigrare o restare in Germania? Tre differenti risposte di autrici ebree tedesche di seconda generazione (Barbara Honigmann, Lea Fleischmann, Esther Dischereit

    Directory of Open Access Journals (Sweden)

    Alessandro Costazza

    2014-04-01

    Full Text Available The purpose of this paper is to investigate, through the analysis of the writings of three German Jewish authors of second generation – Lea Fleischmann, Esther Dischereit and Barbara Honigmann – their different responses to the complex post-war situation of Jews in both West- and East-Germany. Despite the different origins and experiences of their parents under Nazism, all three make in their youth the painful experience of a Judaism lived mainly as absence, as silence about the past and as lack of Jewish tradition and religion. Trying to achieve their own identity, Fleischmann and Dischereit seek a possible integration in post-war West-Germany in the political commitment of the 70s, but must then recognize that anti-Semitism is still widespread in that country. This discovery compels Fleischmann to leave Germany and seek in Israel and eventually in the religion of her fathers a Jewish identity. Esther Dischereit decides on the contrary to perform in Germany her "exercises to be Jewish", assuming the role of critical conscience of German society. Different is the situation of Barbara Honigmann, born and raised in East-Germany, who reacts to the dominant materialism in that state with a need for spirituality that will take her to seek in religion – lived outside of Germany and so far from "negative symbiosis" between Jews and Germans, but also far from Israel - her own diasporic identity. Despite the three different outcomes resulting from the search for Jewish identity in post-war Germany, for all three authors writing plays a crucial function as memory and critical conscience and since this writing is a German one, it imposes eventually a tight and thorough confrontation with German culture.

  11. Single Piezo-Actuator Rotary-Hammering Drill

    Science.gov (United States)

    Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2011-01-01

    This innovation comprises a compact drill that uses low-axial preload, via vibrations, that fractures the rock under the bit kerf, and rotates the bit to remove the powdered cuttings while augmenting the rock fracture via shear forces. The vibrations fluidize the powered cuttings inside the flutes around the bit, reducing the friction with the auger surface. These combined actions reduce the consumed power and the heating of the drilled medium, helping to preserve the pristine content of the produced samples. The drill consists of an actuator that simultaneously impacts and rotates the bit by applying force and torque via a single piezoelectric stack actuator without the need for a gearbox or lever mechanism. This reduces the development/fabrication cost and complexity. The piezoelectric actuator impacts the surface and generates shear forces, fragmenting the drilled medium directly under the bit kerf by exceeding the tensile and/or shear strength of the struck surface. The percussive impact action of the actuator leads to penetration of the medium by producing a zone of finely crushed rock directly underneath the struck location. This fracturing process is highly enhanced by the shear forces from the rotation and twisting action. To remove the formed cuttings, the bit is constructed with an auger on its internal or external surface. One of the problems with pure hammering is that, as the teeth become embedded in the sample, the drilling efficiency drops unless the teeth are moved away from the specific footprint location. By rotating the teeth, they are moved to areas that were not fragmented, and thus the rock fracturing is enhanced via shear forces. The shear motion creates ripping or chiseling action to produce larger fragments to increase the drilling efficiency, and to reduce the required power. The actuator of the drill consists of a piezoelectric stack that vibrates the horn. The stack is compressed by a bolt between the backing and the horn in order to

  12. 78 FR 75511 - Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-500-1A11 Series Airplanes...

    Science.gov (United States)

    2013-12-12

    ... Inc., Models BD-500-1A10 and BD- 500-1A11 Series Airplanes; Electronic Flight Control System: Control... Inc. Models BD-500-1A10 and BD-500-1A11 series airplanes. These airplanes will have a novel or unusual... comments, data, or views. The most helpful comments reference a specific portion of the special conditions...

  13. D/H Ratios of Marine Lipids from Santa Barbara Basin Sediments

    Science.gov (United States)

    Li, C.; Sessions, A.; Kinnaman, F.; Valentine, D.

    2006-12-01

    With the early successful application of compound-specific D/H analyses to reconstructing paleoclimate records, most subsequent research has focused on understanding organic D/H fractionations in terrestrial environments. Thus we still know very little about natural D/H variations in lipids derived from marine organisms, or indeed if any such variations exist. We have therefore conducted an extensive survey of lipid δD values in two sediment cores collected in the Santa Barbara Basin. These data allow us to examine 1) variations between the lipid products of different organisms, 2) down-core variations due to diagenesis, and 3) differences between sediments deposited under oxic or anoxic bottom-water conditions. Our results show that considerable D/H variability between different marine products does exist. δD values of n-alkanes (except n-C35) ranged from -94 to -175 ‰, and exhibit a systematic offset between odd and even carbon numbers. The δD value of n-C35 is anomalous at -220‰. Isotopic compositions of n-alkanols range from -126 to -221 , with a pattern of progressive D depletion with chain length observed for free alcohols. δD values of sterols range from -215 to -309‰, and show no systematic variation with carbon number. However, offsets do exist between the saturated, monounsaturated, and diunsaturated sterols. Sterols as a group are strongly depleted in D relative to the bacterial-derived hopanols (-166 to -232‰), suggesting possible differences in biosynthetic fractionations by bacteria and eukaryotes. Phytol and phytane δD values roughly ranged from -360 to -410‰, while phytanol was systematically enriched at -300 to -340‰. Fatty acids encompassed much greater variability, with dD values ranging from -55 to -270‰. In general, saturated fatty acids are enriched in D relative to their unsaturated analogs, and long-chain (>C24) acids are enriched in D relative to short-chain (

  14. Differences in semen freezability and intracellular ATP content between the rooster (Gallus gallus domesticus) and the Barbary partridge (Alectoris barbara).

    Science.gov (United States)

    Madeddu, M; Berlinguer, F; Pasciu, V; Succu, S; Satta, V; Leoni, G G; Zinellu, A; Muzzeddu, M; Carru, C; Naitana, S

    2010-10-01

    This study aimed to compare viability, ATP content, and DNA integrity of rooster (Gallus gallus domesticus) and Barbary partridge (Alectoris barbara) fresh and frozen spermatozoa in order to identify factors possibly related to differences in semen freezability. Ejaculates were obtained from March to May by the abdominal massage method from 3 adult roosters and 12 adult Barbary partridges. Semen was frozen with different cryoprotectants using Lake's diluents as a base medium: 1) glycerol 11%; 2) glycerol 11% and trehalose 70 mmol/L; 3) dimethylacetamide (DMA) 6%; 4) DMA 6% and trehalose 70 mmol/L. Both fresh and frozen semen showed a lower viability and higher intracellular ATP concentrations in the Barbary partridge compared with the rooster (P rooster a higher viability was recorded when semen was frozen in glycerol containing media compared to DMA (P rooster DNA fragmentation was higher in DMA ctr medium compared with the other media and with values found in Barbary partridge semen frozen in the same medium (P rooster and the Barbary partridge and the wide variation observed in ATP levels may account for differences in semen freezability between the two species. (c) 2010 Elsevier Inc. All rights reserved.

  15. Text as Locus, Inscription as Identity: On Barbara Honigmann's Roman von einem Kinde

    Directory of Open Access Journals (Sweden)

    Marilyn Sibley Fries

    1990-06-01

    Full Text Available Barbara Honigmann's Roman von einem Kinde (1986 constitutes the author's attempt at narrative self-definition. In this and other regards, it is similar to Christa Wolf's Kindheitsmuster (1976; Patterns of Childhood, 1980 , with which it is briefly compared. Honigmann's slim collection of stories, conceived by her as "sketches for self-portraits and landscapes," depicts the absolute isolation ofthe female Jewish narrator in the GDR and her search for community ( Heimat via language. Simultaneously, it records that narrator's desire to identify "places of transition," "boundaries at which conditions change" without fixing these in a static prison of text. The narrator-mother merges with the child born in the first story as, in the following ones, she comprehends the insignificance of her social (context, finally to simulate her own birth and the envied preverbal infant stage by means of self-expulsion—from the GDR via a "threefold salto mortale into the "Judaism of the Thora" in Strasbourg—into a "foreign language among foreign people." The narrator/author's position at a transitional boundary, underscored by the self-portrait that adorns the book's dust jacket, acknowledges the territory between two illegible texts and her reluctance to sacrifice "true reality" ( wahre Wirklichkeit by transforming "human being" into "text" ( Mensch into Schrift —a reluctance engendered by her meeting with Gershom Scholem in the central story of the volume.

  16. Orbital- to Sub-Orbital-Scale Cyclicity in Seismic Reflections and Sediment Character in Early to Middle Pleistocene Mudstone, Santa Barbara Basin, California

    Science.gov (United States)

    Peterson, C. D.; Behl, R. J.; Nicholson, C.; Lisiecki, L. E.; Sorlien, C. C.

    2009-12-01

    High-resolution seismic reflection records and well logs from the Santa Barbara Channel suggest that large parts of the Pleistocene succession records climate variability on orbital to sub-orbital scales with remarkable sensitivity, much like the well-studied sediments of the last glacial cycle (ODP Site 893). Spectral analysis of seismic reflection data and gamma ray logs from stratigraphically similar Pleistocene sections finds similar cyclic character and shifts through the section. This correlation suggests that acoustic impedance and physical properties of sediment are linked by basin-scale, likely climatically-driven, oscillations in lithologic composition and fabric during deposition, and that seismic profiling can provide a method for remote identification and correlation of orbital- and sub-orbital-scale sedimentary cyclicity. Where it crops out along the northern shelf of the central Santa Barbara Channel, the early to middle Pleistocene succession (~1.8-1.2 Ma) is a bathyal hemipelagic mudstone with remarkably rhythmic planar bedding, finely laminated fabric, and well-preserved foraminifera, none of which have been significantly altered, or obscured by post-depositional diagenesis or tectonic deformation. Unlike the coarser, turbiditic successions in the central Ventura and Los Angeles basins, this sequence has the potential to record Quaternary global climate change at high resolution. Seismic reflection data (towed chirp) collected on the R/V Melville 2008 Cruise (MV08) penetrate 10's of meters below seafloor into a ~1 km-long sequence of south-dipping seismic reflectors. Sampling parallel to the seafloor permits acquisition of consistent signal amplitude for similar reflectors without spreading loss. Based on established age ranges for this section, sedimentation rates may range from 0.4 to 1.4 meters/kyr, therefore suggesting that the most powerful cycles are orbital- to sub-orbital-scale. Discrete sets of cycles with high power show an abrupt shift

  17. Time series data correction for the Chang'E-1 gamma-ray spectrometer

    Institute of Scientific and Technical Information of China (English)

    Li-Yan Zhang; Yong-Liao Zou; Jian-Zhong Liu; Jian-Jun Liu; Ji Shen; Ling-Li Mu; Xin Ren; Wei-Bin Wen; Chun-Lai Li

    2011-01-01

    The main goal of the gamma-ray spectrometer (GRS) onboard Chang'E-l (CE-1) is to acquire global maps of elemental abundances and their distributions on the moon, since such maps will significantly improve our understanding of lunar formation and evolution. To derive the elemental maps and enable research on lunar formation and evolution, raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray spectra. The data correction procedures for the CE-1 GRS time series data are thoroughly described. The processing procedures to create the time series gamma-ray spectra described here include channel processing, optimal data selection, energy calibration, gain correction, dead time correction, geometric correction, orbit altitude normalization, eliminating unusable data and galactic cosmic ray correction. Finally, descriptions are also given on data measurement uncertainties, which will help the interested scientists to understand and estimate various uncertainties associated with the above data processing.

  18. A contribution to water hammer analysis in pumped-storage power plants; Ein Beitrag zur Druckstossberechnung von Pumpspeicheranlagen

    Energy Technology Data Exchange (ETDEWEB)

    Hoeller, Stefan; Jaberg, Helmut [TU Graz (Austria). Inst. fuer Hydraulische Stroemungsmaschinen

    2013-03-01

    The operation of pumped-storage power plants induces a highly transient fluid flow in the penstock of high head water power plants. In the planning phase a reliable prediction of the transient plant behaviour in unsteady load cases such as e.g. machine start or switching load cases is necessary. Numerical simulation methods provide a tool to calculate the occurring pressure pulsations or mass oscillations as well as for the optimization of the transient behaviour. Commercial software-packages for water hammer simulations usually do not provide numerical models for a realistic calculation of complex components like surge tanks, turbines or emergency closing valves in a high head water power plant. But especially these components need to be modelled correctly in order to get a significant and reliable solution. This article shows the practice ofthe development of a custom-designed numerical model on the example of a pump turbine. (orig.)

  19. Water hammer analysis. Dynamic simulation model check valve piston; Analisis del golpe de airete. Modelo de simulacion dinamica de valvula de retencion piston

    Energy Technology Data Exchange (ETDEWEB)

    Royo, B.; Valdes, R.

    2012-11-01

    This report contains the description and the results of the dynamic simulation model that has been developed to predict the behaviour of one of our lift check valve design. The aim of the model is not only to simulate the closing process of the valve and to product the magnitude of the water hammer effect that may appear immediately after the valve closing, but also to simulate several design version until obtain the optimum which further minimizes such effect. the input data used for this study ensure reliable results since they represent a real system. (Author)

  20. Dead-blow hammer design applied to a calibration target mechanism to dampen excessive rebound

    Science.gov (United States)

    Lim, Brian Y.

    1991-01-01

    An existing rotary electromagnetic driver was specified to be used to deploy and restow a blackbody calibration target inside of a spacecraft infrared science instrument. However, this target was much more massive than any other previously inherited design applications. The target experienced unacceptable bounce when reaching its stops. Without any design modification, the momentum generated by the driver caused the target to bounce back to its starting position. Initially, elastomeric dampers were used between the driver and the target. However, this design could not prevent the bounce, and it compromised the positional accuracy of the calibration target. A design that successfully met all the requirements incorporated a sealed pocket 85 percent full of 0.75 mm diameter stainless steel balls in the back of the target to provide the effect of a dead-blow hammer. The energy dissipation resulting from the collision of balls in the pocket successfully dampened the excess momentum generated during the target deployment. The disastrous effects of new requirements on a design with a successful flight history, the modifications that were necessary to make the device work, and the tests performed to verify its functionality are described.