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Sample records for machine trolley seismic

  1. Multi Canister Overpack (MCO) Handling Machine Trolley Seismic Uplift Constraint Design Loads

    International Nuclear Information System (INIS)

    SWENSON, C.E.

    2000-01-01

    The MCO Handling Machine (MHM) trolley moves along the top of the MHM bridge girders on east-west oriented rails. To prevent trolley wheel uplift during a seismic event, passive uplift constraints are provided as shown in Figure 1-1. North-south trolley wheel movement is prevented by flanges on the trolley wheels. When the MHM is positioned over a Multi-Canister Overpack (MCO) storage tube, east-west seismic restraints are activated to prevent trolley movement during MCO handling. The active seismic constraints consist of a plunger, which is inserted into slots positioned along the tracks as shown in Figure 1-1. When the MHM trolley is moving between storage tube positions, the active seismic restraints are not engaged. The MHM has been designed and analyzed in accordance with ASME NOG-1-1995. The ALSTHOM seismic analysis (Reference 3) reported seismic uplift restraint loading and EDERER performed corresponding structural calculations. The ALSTHOM and EDERER calculations were performed with the east-west seismic restraints activated and the uplift restraints experiencing only vertical loading. In support of development of the CSB Safety Analysis Report (SAR), an evaluation of the MHM seismic response was requested for the case where the east-west trolley restraints are not engaged. For this case, the associated trolley movements would result in east-west lateral loads on the uplift constraints due to friction, as shown in Figure 1-2. During preliminary evaluations, questions were raised as to whether the EDERER calculations considered the latest ALSTHOM seismic analysis loads (See NCR No. 00-SNFP-0008, Reference 5). Further evaluation led to the conclusion that the EDERER calculations used appropriate vertical loading, but the uplift restraints would need to be re-analyzed and modified to account for lateral loading. The disposition of NCR 00-SNFP-0008 will track the redesign and modification effort. The purpose of this calculation is to establish bounding seismic

  2. A modern automatic Carriage-Trolley Position Control System for Dhruva fuelling machine

    International Nuclear Information System (INIS)

    Agrawal, Ankit; Hari Balakrishna; Narvekar, J.P.; Sanadhya, Vivek

    2014-01-01

    A fully automatic absolute encoder based position control system has been designed developed implemented and commissioned for the Dhruva Fuelling Machine A (FM/A). This supports both the coarse and fine positioning modes. Provision for fully manual positioning as a standby system has been retained. This system replaces the ageing peg counting based incremental positioner used briefly during the early period after the Dhruva FM/A was commissioned. The older system suffered from peg detection skipping problems; hence it was not being used. Only full manual positioning was being carried out. This paper describes the automatic Carriage Trolley Position Control System (CTPCS). (author)

  3. A trolley mounted magazine for reactor maintenance

    International Nuclear Information System (INIS)

    Brennan, P.J.; Madani, M.; Ridgway, G.H.; Lundy, E.; Knight, D.

    2009-01-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  4. A trolley mounted magazine for reactor maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, P.J.; Madani, M.; Ridgway, G.H. [GE Hitachi Nuclear Energy Canada, Peterborough, Ontario (Canada)], E-mail: patrick1.brennan@ge.com, mehdi.madani@ge.com, guy.ridgway@ge.com; Lundy, E.; Knight, D. [IM and CS (Inspection, Maintenance and Commerical Services), Ontario Power Generation, Ajax, Ontario (Canada)], E-mail: erroll.lundy@opg.com, david.knight@opg.com

    2009-03-15

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  5. A trolley mounted magazine for reactor maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, P.J.; Madani, M.; Ridgway, G.H., E-mail: patrick1.brennan@ge.com, E-mail: mehdi.madani@ge.com, E-mail: guy.ridgway@ge.com [GE Hitachi Nuclear Energy Canada, Peterborough, Ontario (Canada); Lundy, E.; Knight, D., E-mail: erroll.lundy@opg.com, E-mail: david.knight@opg.com [Ontario Power Generation, Inspection, Maintenance and Commercial Services, Ajax, Ontario (Canada)

    2008-07-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  6. A trolley mounted magazine for reactor maintenance

    International Nuclear Information System (INIS)

    Brennan, P.J.; Madani, M.; Ridgway, G.H.; Lundy, E.; Knight, D.

    2008-01-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  7. Evaluation of Multi Canister Overpack (MCO) Handling Machine Uplift Restraint for a Seismic Event During Repositioning Operations

    International Nuclear Information System (INIS)

    SWENSON, C.E.

    2000-01-01

    Insertion of the Multi-Canister Overpack (MCO) assemblies into the Canister Storage Building (CSB) storage tubes involves the use of the MCO Handling Machine (MHM). During MCO storage tube insertion operations, inadvertent movement of the MHM is prevented by engaging seismic restraints (''active restraints'') located adjacent to both the bridge and trolley wheels. During MHM repositioning operations, the active restraints are not engaged. When the active seismic restraints are not engaged, the only functioning seismic restraints are non-engageable (''passive'') wheel uplift restraints which function only if the wheel uplift is sufficient to close the nominal 0.5-inch gap at the uplift restraint interface. The MHM was designed and analyzed in accordance with ASME NOG-1-1995. The ALSTHOM seismic analysis reported seismic loads on the MHM uplift restraints and EDERER performed corresponding structural calculations to demonstrate structural adequacy of the seismic uplift restraint hardware. The ALSTHOM and EDERER calculations were performed for a parked MHM with the active seismic restraints engaged, resulting in uplift restraint loading only in the vertical direction. In support of development of the CSB Safety Analysis Report (SAR), an evaluation of the MHM seismic response was requested for the case where the active seismic restraints are not engaged. If a seismic event occurs during MHM repositioning operations, a moving contact at a seismic uplift restraint would introduce a friction load on the restraint in the direction of the movement. These potential horizontal friction loads on the uplift restraints were not included in the existing restraint hardware design calculations. One of the purposes of the current evaluation is to address the structural adequacy of the MHM seismic uplift restraints with the addition of the horizontal friction associated with MHM repositioning movements

  8. Self-propelled trolley with articulated arms, tank and disengageable driving device to be mounted on the said trolley

    International Nuclear Information System (INIS)

    Asty, M.; Lerat, B.; Saglio, R.; Viard, J.

    1984-01-01

    This trolley can move between two walls, especially in the vessels inter-space of a fast reactor. This trolley has two wheels keeping in contact with one of the two walls and connected to the body of the trolley by two longitudinal arms, and two wheels keeping in contact with the other wall symmetrically mounted with regard to the others and connected to the body of the trolley by two side arms. The longitudinal and side arm are folding to allow the passage of the present device through a penetration shaft. The trolley carries a tank feeding a liquid onto the walls. The liquid is used for coupling the walls to ultrasonic transducers mounted on the trolley and employed to locate any defects in the walls. The present invention can be applied to ultrasonic testing of fast reactor vessels, to detect defects in metal walls, especially at welds [fr

  9. Design of automatic mobile trolley using ultrasonic sensors

    Science.gov (United States)

    Dodi Suryanto, Eka; Siagian, Hendrik; Perangin-Angin, Despaleri; Sashanti, Rahayu; Yogen, Suthes

    2018-04-01

    An automatic mobile trolley was a prototype of wheel robot that serves as a trolley or shopping cart. This paper proposed an automatic mobile trolley using ultrasonic sensors. It can follow human movement automatically. It did not need to be encouraged or withdrawn. It would make an easier shopping for people as customers. The trolley controlled by a microcontroller module unit. It can stop, turn right, turn left, forward and backward. It can follow wherever they go, during they were in range. Based on the test results, the trolley succeeded to move forward by 80%, move backward 80%, turn left, 70%, turn right 70%, and stop 80%.

  10. Project survey for trolley-bus transport; Johdinautoliikenteen hankeselvitys

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, T.; Eklund, P.; Airaksinen, S.; Maettoe, R.; Laehdetie, A.

    2011-04-15

    To investigate the feasibility and rationality of the revival of trolley bus traffic in Helsinki a full size project plan was conducted for a variety of alternatives. This included a survey on the latest developments of the trolley bus technology, three optional plans for route network, a budgetary level design for a fully functional depot in Koskela bus depot, examination of urban landscape structures, a study on organisational options, particular technical specifications applicable on suitable trolley buses and an examination of the impacts on the environment and on the future development of public transport. The basic concept of a trolley bus as a means of electric public transport vehicle has found its form over the years, but all the components of the system undergo at present intensive development. In context of this survey also the option of a fully autonomous electric bus powered by accumulators or fuel cells and the like was investigated. However, such technology is still totally inadequate for a heavy duty bus. There are no economically competitive and effective systems available as yet. The trolley bu is the far most reliable system and gives the best life cycle economy for a foreseeable future. Earliest estimates for alternative electric technologies in regular bus service are viable just after one investment cycle some time beyond 2030. Then it should be possible to run without the support of a comprehensive overhead line. The latest achievements in the development of trolley bus are auxiliary engine and accumulator systems allowing for more autonomous propulsion. Nowadays, trolley buses are equipped with an auxiliary power unit that alleviates the traditional restrictions of the overhead line. The modern trolley bus may run short distances without the trolley lines. Recuperation of the kinetic energy at deceleration (braking) either into the overhead line network or by storing it in the vehicle is one of the characteristics of modern trolley buses

  11. Reactor refueling machine simulator

    International Nuclear Information System (INIS)

    Rohosky, T.L.; Swidwa, K.J.

    1987-01-01

    This patent describes in combination: a nuclear reactor; a refueling machine having a bridge, trolley and hoist each driven by a separate motor having feedback means for generating a feedback signal indicative of movement thereof. The motors are operable to position the refueling machine over the nuclear reactor for refueling the same. The refueling machine also has a removable control console including means for selectively generating separate motor signals for operating the bridge, trolley and hoist motors and for processing the feedback signals to generate an indication of the positions thereof, separate output leads connecting each of the motor signals to the respective refueling machine motor, and separate input leads for connecting each of the feedback means to the console; and a portable simulator unit comprising: a single simulator motor; a single simulator feedback signal generator connected to the simulator motor for generating a simulator feedback signal in response to operation of the simulator motor; means for selectively connecting the output leads of the console to the simulator unit in place of the refueling machine motors, and for connecting the console input leads to the simulator unit in place of the refueling machine motor feedback means; and means for driving the single simulator motor in response to any of the bridge, trolley or hoist motor signals generated by the console and means for applying the simulator feedback signal to the console input lead associated with the motor signal being generated by the control console

  12. Structural Analysis of Advanced Refueling Machine of APR1400

    International Nuclear Information System (INIS)

    Cho, J. R.; Kim, Y. H.; Park, B. T.; Park, J. B.; Jung, J. H.

    2007-01-01

    The Refueling Machine (RM) consists of two structural parts of bridge and trolley. The bridge structure is approximately 8.5 m long and 5 m wide and is primarily composed of two deep wide flange sections spanning the rector area at the operating level. The trolley is mounted on wheels that roll on the rails of the bridge. Vertical movements of trolley and bridge are restricted by guide rollers. In this paper, dynamic and structural analyses based on the earthquake spectrum are carried out to verify the structural integrity of advanced refueling machine. It is done by 3-dimensional finite element analysis using ANSYS software

  13. Antero-posterior (AP) pelvis x-ray imaging on a trolley: Impact of trolley design, mattress design and radiographer practice on image quality and radiation dose

    International Nuclear Information System (INIS)

    Tugwell, J.R.; England, A.; Hogg, P.

    2017-01-01

    Introduction: Physical and technical differences exist between imaging on an x-ray tabletop and imaging on a trolley. This study evaluates how trolley imaging impacts image quality and radiation dose for an antero-posterior (AP) pelvis projection whilst subsequently exploring means of optimising this imaging examination. Methods: An anthropomorphic pelvis phantom was imaged on a commercially available trolley under various conditions. Variables explored included two mattresses, two image receptor holder positions, three source to image distances (SIDs) and four mAs values. Image quality was evaluated using relative visual grading analysis with the reference image acquired on the x-ray tabletop. Contrast to noise ratio (CNR) was calculated. Effective dose was established using Monte Carlo simulation. Optimisation scores were derived as a figure of merit by dividing effective dose with visual image quality scores. Results: Visual image quality reduced significantly (p < 0.05) whilst effective dose increased significantly (p < 0.05) for images acquired on the trolley using identical acquisition parameters to the reference image. The trolley image with the highest optimisation score was acquired using 130 cm SID, 20 mAs, the standard mattress and platform not elevated. A difference of 12.8 mm was found between the image with the lowest and highest magnification factor (18%). Conclusion: The acquisition parameters used for AP pelvis on the x-ray tabletop are not transferable to trolley imaging and should be modified accordingly to compensate for the differences that exist. Exposure charts should be developed for trolley imaging to ensure optimal image quality at lowest possible dose. - Highlights: • Acquisition parameters used for AP pelvis imaging on a trolley need adapting from those used on the x-ray tabletop. • Radiation dose significantly increases for trolley imaging. • An increase in SID can reduce radiation dose and magnification for trolley imaging

  14. Stabilizer for seismically exposed bridge cranes

    International Nuclear Information System (INIS)

    Engelke, M.; Kuhr, H.

    1982-01-01

    The invention concerns a stabilizer for seismically exposed bridge cranes in reactor buildings. The trolley and the crane bridge are fitted with the stabilizer consisting of a bipartite safety catch which is connected with a joint and able to take up the vertical loads during an earthquake. This stabilizer is suitable for all kinds of bridge cranes operated in seismically active regions

  15. Design of fuelling machine bridge and carriage to meet seismic qualification requirements

    International Nuclear Information System (INIS)

    Ghare, A.B.; Chhatre, A.G.; Vyas, A.K.; Bhambra, H.S.

    1996-01-01

    During each refuelling operation, the boundary of Primary heat transport system is extended up to Fuelling Machines. A breach in the pressure boundary of Fuelling Machine in this condition would cause a loss of coolant accident. Fuelling Machines are also used for transit storage of spent fuel bundles till discharged to fuel transfer system. Therefore, a fuelling machine, including its support structures, is required to be seismically qualified for both on-reactor ( coupled ) mode and off-reactor (uncoupled) mode. The fuelling machine carriage used in the first generation of Indian PHWRs is a mobile equipment on wheels moving over fixed rails. As this configuration was found unsuitable for withstanding strong seismic disturbances, a bridge type design with fixed columns was evolved for the next generation of reactors. Initially, the seismic analysis of the fuelling machine bridge and carriage was done using static structural analysis and values of natural frequencies for various structures were computed. The structures were suitably modified based on the results of this analysis. Subsequently, a detailed dynamic seismic analysis using finite element model has been completed for both coupled and uncoupled conditions. The qualification of the structure has been carried out as per ASME section 111 Division 1, sub section NF. Details of the significant design features, static and dynamic analysis, results and conclusions are given in the presentation. (author). 4 refs., 4 tabs., 7 figs

  16. Design of fuelling machine bridge and carriage to meet seismic qualification requirements

    Energy Technology Data Exchange (ETDEWEB)

    Ghare, A B; Chhatre, A G; Vyas, A K; Bhambra, H S [Nuclear Power Corporation of India Ltd., Mumbai (India)

    1997-12-31

    During each refuelling operation, the boundary of Primary heat transport system is extended up to Fuelling Machines. A breach in the pressure boundary of Fuelling Machine in this condition would cause a loss of coolant accident. Fuelling Machines are also used for transit storage of spent fuel bundles till discharged to fuel transfer system. Therefore, a fuelling machine, including its support structures, is required to be seismically qualified for both on-reactor ( coupled ) mode and off-reactor (uncoupled) mode. The fuelling machine carriage used in the first generation of Indian PHWRs is a mobile equipment on wheels moving over fixed rails. As this configuration was found unsuitable for withstanding strong seismic disturbances, a bridge type design with fixed columns was evolved for the next generation of reactors. Initially, the seismic analysis of the fuelling machine bridge and carriage was done using static structural analysis and values of natural frequencies for various structures were computed. The structures were suitably modified based on the results of this analysis. Subsequently, a detailed dynamic seismic analysis using finite element model has been completed for both coupled and uncoupled conditions. The qualification of the structure has been carried out as per ASME section 111 Division 1, sub section NF. Details of the significant design features, static and dynamic analysis, results and conclusions are given in the presentation. (author). 4 refs., 4 tabs., 7 figs.

  17. The Fermiac or Fermi's Trolley

    Science.gov (United States)

    Coccetti, F.

    2016-03-01

    The Fermiac, known also as Fermi's trolley or Monte Carlo trolley, is an analog computer used to determine the change in time of the neutron population in a nuclear device, via the Monte Carlo method. It was invented by Enrico Fermi and constructed by Percy King at Los Alamos in 1947, and used for about two years. A replica of the Fermiac was built at INFN mechanical workshops of Bologna in 2015, on behalf of the Museo Storico della Fisica e Centro Studi e Ricerche "Enrico Fermi", thanks to the original drawings made available by Los Alamos National Laboratory (LANL). This reproduction of the Fermiac was put in use, and a simulation was developed.

  18. Efficacy of paediatric anaesthetic trolleys: A call for a basic standard and layout.

    Science.gov (United States)

    Griffiths, Sian E; Boleat, Elizabeth; Goodwin, Alison; Sheikh, Asme; Goonasekera, Chulananda

    2015-01-01

    Providing safe anaesthesia to children especially in emergency situations goes hand in hand with instant availability of appropriately sized equipment and monitoring. This is best achieved using a designated paediatric anaesthetic trolley containing essential equipment. Guidance for the contents of such trolleys is neither explicit nor standard. We used a survey and a qualitative enquiry to develop a checklist suitable for standardisation of contents and layout of paediatric anaesthetic trolleys. We conducted an observational study of our current practice and paediatric anaesthetic trolleys in a tertiary care hospital. We also performed a qualitative enquiry from experienced paediatric anaesthetists and operating department practitioners.We developed an empirical checklist to ensure the minimum 'essential' equipment is available on these trolleys and implemented a standard layout to facilitate its use. We identified 11 areas in our hospital where anaesthesia is provided to children, each with a designated paediatric anaesthetic trolley. There were considerable deficiencies of items in all areas with no standard pattern or layout. Different types of trolleys contributed to the confusion. In addition, overstocking of inappropriate items hindered its efficient use. Standardising the contents and layout of the paediatric anaesthetic trolley is an essential pre-requisite for safer paediatric anaesthetic practice.

  19. Multipurpose layout drawing of metalware of bridge crane load trolley

    Directory of Open Access Journals (Sweden)

    Goncharov K.A.

    2017-03-01

    Full Text Available Multipurpose layout drawing of metalware of bridge crane load trolley is proposed. The numerical analysis of proposed layout drawing is conducted using the example of bridge crane load trolley with capacity of 20 t. This analysis is carried out using the finite element method.

  20. Designing and Developing Automatic Trolley for Washing and Dressing the Wounds

    Directory of Open Access Journals (Sweden)

    Golvardi Yazdi M. S.

    2017-12-01

    Full Text Available Introduction:Many items are needed for dressing including sterile dressing set, antiseptic and washing solutions, leucoplast tape, waste bin for infectious garbage, waste bin for noninfectious garbage, safe disposal trash for sharp cutting instruments, bedpan and sometimes drugs. All the items are laid out on a simple wheeled trolley. The multiplicity of items together with problems in placing tools on trolley, forgetting some items, disturbing sterile condition, falling and damaging equipment and the need for at least two people for each procedure, all are the reasons to design and develop Automatic Trolley for Washing and Dressing the Wounds. Material and Method: To develop a mobile unit which meets our needs for dressing, the trolley patents registered in America and different companies were evaluated as well as the materials and methods used while dressing were considered. Results: Automatic Trolley for Washing and Dressing the Wounds was designed and developed. It comprises the followings: drawer, waste bin for infectious garbage, waste bin for noninfectious garbage, shelves for serum and betadine solution, serum stand, peristaltic pump, flexible tube for connecting serum, a place for bedpan, foot pedal for serum flow, two eye-sensor chambers for solution betadine and scrub, an auxiliary work surface. Conclusion: Due to the usual requirements for dressing, we have designed an equipped mobile unit which covers all the objectives of dressing and increases the speed of procedure. Moreover, due to the contrived equipment on the trolley, procedures are done quickly and second person is not required to assist. Automatic Trolley for Washing and Dressing the Wounds is made up of stainless steel which could be mass housing and commercializing which would play a deserving role in improving the fundamentals of health care and wound treatment.

  1. Mathematic model of three-phase induction machine connected to advanced inverter for traction system for electric trolley

    Directory of Open Access Journals (Sweden)

    LIVIU S. BOCÎI

    2013-06-01

    Full Text Available This paper establishes a mathematical model of induction machine connected to a frequency inverter necessary to adjust the electric motor drive. The mathematical model based on the Park's theory allows the analysis of the whole spectrum (electric car – frequency inverter to drive the electric trolley bus made on ASTRA Bus Arad (Romania. To remove higher order harmonics, the PWM waveform of supply voltage is used, set in the general case. Operating characteristics of electric motor drive are set to sub-nominal frequency (f Bele 2007.Este documento estabelece um modelo matemático de máquina de indução conectado a um inversor de frequência necessário para ajustar o motor de acionamento elétrico. O modelo matemático baseado na Teoria de Park permite a análise de todo o espectro (carro elétrico com inversor de frequência para dirigir o ônibus elétrico feito em ASTRA Bus Arad (Romênia. Para remover harmônicas de ordem mais alta, a forma de onda da tensão de alimentação PWM é utilizado, definido no caso geral. Características de funcionamento do motor de acionamento elétrico são definidas para frequência sub-nominal (f

  2. A Shear-Wave Seismic System to Look Ahead of a Tunnel Boring Machine

    NARCIS (Netherlands)

    Bharadwaj, Pawan; Drijkoningen, G.G.; Mulder, W.A.; Tscharner, Thomas; Jenneskens, Rob

    2016-01-01

    The Earth’s properties, composition and structure ahead of a tunnel boring machine (TBM) should be mapped for hazard assessment during excavation. We study the use of seismic-exploration techniques for this purpose. We focus on a seismic system for soft soils, where shear waves are better and easier

  3. Reduction of discomfort in pushing an industrial trolley using ergonomics

    Science.gov (United States)

    Kumar, M. Wilson; Vijay, S. J.; Vasudev, K. L.; Darius Gnanaraj, S.

    2017-11-01

    Poor design of industrial trolleys lead to more compressive stress on the low back of industrial workers. The research work reported in this paper recommends a handle height of an industrial trolley for use by the local population, which reduces the compressive stress on the low back. Experiments were conducted in a laboratory on five subjects of varying stature 165, 173, 174, 175 and 182 cm, with five different handle heights 90, 95, 100, 105 and 110 cm. A four wheeled trolley has been used to conduct the experiments. Caster wheels diameters of 100, 125 and 150 mm made of polyurethane were used. It is found that a handle height of 110 cm allows the users to exert minimum force during the initial pushing. A biomechanical model was employed to calculate the compressive force experienced by L5/S1 disc and it is found that the compressive load will be the least when the handle height is 110 cm. Optimization of handle height using Genetic Algorithm approach, Heart rate analysis and EMG analysis confirm that a handle height of 110 cm and a wheel diameter of 150 mm will reduce the discomfort of industry workers pushing trolleys.

  4. The Fermiac or Fermi's Trolley

    International Nuclear Information System (INIS)

    Coccetti, F.

    2016-01-01

    The Fermiac, known also as Fermi’s trolley or Monte Carlo trolley, is an analog computer used to determine the change in time of the neutron population in a nuclear device, via the Monte Carlo method. It was invented by Enrico Fermi and constructed by Percy King at Los Alamos in 1947, and used for about two years. A replica of the Fermiac was built at INFN mechanical workshops of Bologna in 2015, on behalf of the 'Museo Storico della Fisica e Centro Studi e Ricerche' “Enrico Fermi”, thanks to the original drawings made available by Los Alamos National Laboratory (LANL). This reproduction of the Fermiac was put in use, and a simulation was developed.

  5. Supporting the Supermarket Shopping Experience through a Context-Aware Shopping Trolley

    DEFF Research Database (Denmark)

    Black, Darren; Clemmensen, Nils Jakob; Skov, Mikael B.

    2009-01-01

    Shopping in the real world is becoming an increasingly interactive experience as stores integrate various technologies to support shoppers. Based on an empirical study of supermarket shoppers, we designed a mobile context-aware system called the Context- Aware Shopping Trolley (CAST). The aim...... of the system is to support shopping in supermarkets through context-awareness and acquiring user attention. Thus, the interactive trolley guides and directs shoppers in the handling and finding of groceries. An empirical evaluation showed that shoppers using CAST adapted in different shopping behavior than...... traditional trolley shoppers by exhibiting a more uniform behavior in terms of product sequence collection and ease of finding products and thus, CAST supported the shopping experience....

  6. Nonlinear Vibration of Ladle Crane due to a Moving Trolley

    Directory of Open Access Journals (Sweden)

    Yunsheng Xin

    2018-01-01

    Full Text Available The structural vibration of the main beam of a crane causes fatigue damage and discomfort to the driver. The swing of the payload has an effect on positioning precision, especially for a ladle crane, and this directly affects production safety. To study the influence of system parameters on the vibration of a crane’s main beam and the angle of the payload, a system consisting of the main beam, trolley, payload, and cabin was constructed. A rigid-flexible coupling dynamic model of a moving trolley with a hanging payload that moves on the flexible main beam with a concentrated cabin mass is established, and the direct integration method is used to solve the nonlinear differential equations of system vibration, which are obtained through Lagrange’s equation. Then, the time domain responses of the flexible main beam, payload angle, and cabin vibration are obtained. The influences of the trolley running speed, quality of the payload, and quality and position of the cabin on the vibration of the main beam and payload angle are analyzed. The results indicate that the amplitude of the main beam is directly proportional to the quality of the trolley, payload, and cab; the position of the cabin is closer to the mid-span; the amplitude of the main beam is larger; the structural damping has some influence on the vibration of the main beam; and the swing angle of the payload is related to the maximum running speed of the trolley, acceleration time, and length of the wire rope. In order to reduce the vibration of the main beam and cabin, the connection stiffness of the cabin should be ensured during installation.

  7. Swisstrolley 3 - An articulated trolley bus; SWISSTROLLEY 3. Gelenktrolleybus

    Energy Technology Data Exchange (ETDEWEB)

    Gisler, H.-J.

    2006-07-01

    This illustrated final report for the Swiss Federal Office of Energy (SFOE) takes a look at the Swisstrolley 3 low-floor, articulated trolley bus developed in Switzerland by the Hess AG company. Various features of the variants of the trolley bus, including single vehicle, single and double-articulated buses and bus trailers, are discussed. The reductions achieved in energy consumption, weight and noise are discussed. Typical values for power consumption are presented in graphical form. Economic viability and passenger-friendliness are examined, as are possibilities for further improvement.

  8. Effectiveness and efficiency of the two trolley system as an infection control mechanism in the operating theatre.

    Science.gov (United States)

    Tuisawana, Viliame

    2009-11-01

    A good infection control manager understands the need to prevent a complete cycle of infection. The Infection Control Working Group Manual of Fiji, emphasised that the Cycle of Infection is the series of stage in which infection is spread. Operating theatres have infection control protocols. Most equipments and instruments used in operating theatre circulate within the theatre. The theatre trolleys are a main component in managing an operating theatre but the least recognised. This paper reviews the effectiveness and efficiency of the current two-trolley system as an infection control mechanism in theatre. The paper will discuss infection control using the current trolley system in relation to the layout of Labasa Hospital operating theatre, human resource, equipment standard and random swab results. The following are random swab results of theatre equipments taken by the Infection Control Nurse from 2006 to 2008. The Labasa Hospital Infection Committee have discouraged random swab sample from mid 2008 based on new guidelines on infection control. The two trolley system, in which an allocated outside trolley transports patients from the ward to a semi-sterile area in theatre. The inside trolley which transports the patient to the operating table. The two trolley system means more trolleys, extra staffs for lifting, additional handling of very sick patients, congestion and delay in taking patients to operating table in theatres should be considered. The one-trolley system in theatre greatly reduces the chances of manually lifting patients, thus reducing the risk of patient injury from fall and risk of back injuries to nurses. There are other evident based practices which can compliment the one trolley system for an effective infection control mechanism in theatres. The Fiji Infection Control Manual (2002) emphases the importance of regularly cleaning the environment and equipments in theatre but there is never a mention about using a two trolley system as an

  9. Handling trolley for Argonne M8, Pye Mo 1815, Pye Heavy Duty, etc. remote manipulators

    International Nuclear Information System (INIS)

    Roussel, E.; Labiche, M.; Chevallier, E.

    1962-01-01

    The removal and installation of remote manipulators and periscopes in hot cells are delicate operations requiring a specific handling trolley. This note describes the technical specifications of such a trolley having the following advantages: occupies a minimal space when not in use, easy and efficient fastening and monitoring, smooth moving of the remote manipulators during removal or installation, trolley stability and immobility during operation, requires only two operators

  10. Determination of vertical pressures on running wheels of freight trolleys of bridge type cranes

    Science.gov (United States)

    Goncharov, K. A.; Denisov, I. A.

    2018-03-01

    The problematic issues of the design of the bridge-type trolley crane, connected with ensuring uniform load distribution between the running wheels, are considered. The shortcomings of the existing methods of calculation of reference pressures are described. The results of the analytical calculation of the pressure of the support wheels are compared with the results of the numerical solution of this problem for various schemes of trolley supporting frames. Conclusions are given on the applicability of various methods for calculating vertical pressures, depending on the type of metal structures used in the trolley.

  11. Report on FS survey for project of introduction of highly energy-efficient trolley buses into the Mexico Metropolitan Area in FY 1997; 1997 nendo chosa hokokusho (Mexico city eno sho energy gata trolley bus donyu project FS chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Traffic jam and air pollution by automobiles are currently getting severe in the Mexico Metropolitan Area. Trolley buses were introduced for improving the environment more than ten years ago. Vehicles become too old for use, and their energy efficiency is low. In this project, 200 highly energy-efficient trolley buses are introduced to replace old inefficient trolley buses, which results in the improved traffic convenience in the City and enhanced energy efficiency. The new energy-efficient trolley buses are made of energy-efficient control VVVF inverters produced and exported by MELCO (Mitsubishi Electric Corporation), energy-efficient motors by MELMEX (Mitsubishi Electric Corporation, Mexico), and bodies by MASA which is a major manufacturer of bus bodies. The objective of this research is to analyze the background of introduction of new energy-efficient trolley buses and the effects of the present project. The results of analysis are going to be utilized for future promotion of the Joint Implementation and Clean Development Mechanism. 30 refs., 30 figs., 24 tabs.

  12. Explosion Monitoring with Machine Learning: A LSTM Approach to Seismic Event Discrimination

    Science.gov (United States)

    Magana-Zook, S. A.; Ruppert, S. D.

    2017-12-01

    The streams of seismic data that analysts look at to discriminate natural from man- made events will soon grow from gigabytes of data per day to exponentially larger rates. This is an interesting problem as the requirement for real-time answers to questions of non-proliferation will remain the same, and the analyst pool cannot grow as fast as the data volume and velocity will. Machine learning is a tool that can solve the problem of seismic explosion monitoring at scale. Using machine learning, and Long Short-term Memory (LSTM) models in particular, analysts can become more efficient by focusing their attention on signals of interest. From a global dataset of earthquake and explosion events, a model was trained to recognize the different classes of events, given their spectrograms. Optimal recurrent node count and training iterations were found, and cross validation was performed to evaluate model performance. A 10-fold mean accuracy of 96.92% was achieved on a balanced dataset of 30,002 instances. Given that the model is 446.52 MB it can be used to simultaneously characterize all incoming signals by researchers looking at events in isolation on desktop machines, as well as at scale on all of the nodes of a real-time streaming platform. LLNL-ABS-735911

  13. Feasibility study and technical proposal for seismic monitoring of tunnel boring machine in Olkiluoto

    Energy Technology Data Exchange (ETDEWEB)

    Saari, J.; Lakio, A. (AF-Consult Ltd, Vantaa (Finland))

    2009-01-15

    In Olkiluoto, Posiva Oy has operated a local seismic network since February 2002. The purpose of the microearthquake measurements at Olkiluoto is to improve understanding of the structure, behaviour and long term stability of the bedrock. The studies include both tectonic and excavation-induced microearthquakes. An additional task of monitoring is related to safeguarding of the ONKALO. The possibility to excavate an illegal access to the ONKALO, have been concerned when the safeguards are discussed. Therefore all recorded explosions in the Olkiluoto area and in the ONKALO are located. If a concentration of explosions is observed, the origin of that is found out. Also a concept of hidden illegal explosions, detonated at the same time as the real excavation blasts, has been examined. According to the experience gained in Olkiluoto, it can be concluded that, as long the seismic network is in operation and the results are analysed by a skilled person, it is practically impossible to do illegal excavation by blasts. In this report a possibility of seismic monitoring of illegal excavation done by tunnel boring machine (TBM) has been investigated. Characteristics of the seismic signal generated by the raise boring machine are described. According to this study, it can be concluded that the generated seismic signal can be detected and the source of the signal can be located. However, this task calls for different kind of monitoring system than that, which is currently used for monitoring microearthquakes and explosions. The presented technical proposal for seismic monitoring of TBM in Olkiluoto is capable to detect and locate TBM coming outside the ONKALO area about two months before it would reach the ONKALO. (orig.)

  14. Feasibility study and technical proposal for seismic monitoring of tunnel boring machine in Olkiluoto

    International Nuclear Information System (INIS)

    Saari, J.; Lakio, A.

    2009-01-01

    In Olkiluoto, Posiva Oy has operated a local seismic network since February 2002. The purpose of the microearthquake measurements at Olkiluoto is to improve understanding of the structure, behaviour and long term stability of the bedrock. The studies include both tectonic and excavation-induced microearthquakes. An additional task of monitoring is related to safeguarding of the ONKALO. The possibility to excavate an illegal access to the ONKALO, have been concerned when the safeguards are discussed. Therefore all recorded explosions in the Olkiluoto area and in the ONKALO are located. If a concentration of explosions is observed, the origin of that is found out. Also a concept of hidden illegal explosions, detonated at the same time as the real excavation blasts, has been examined. According to the experience gained in Olkiluoto, it can be concluded that, as long the seismic network is in operation and the results are analysed by a skilled person, it is practically impossible to do illegal excavation by blasts. In this report a possibility of seismic monitoring of illegal excavation done by tunnel boring machine (TBM) has been investigated. Characteristics of the seismic signal generated by the raise boring machine are described. According to this study, it can be concluded that the generated seismic signal can be detected and the source of the signal can be located. However, this task calls for different kind of monitoring system than that, which is currently used for monitoring microearthquakes and explosions. The presented technical proposal for seismic monitoring of TBM in Olkiluoto is capable to detect and locate TBM coming outside the ONKALO area about two months before it would reach the ONKALO. (orig.)

  15. Seismic effects on the reliability of polar cranes for nuclear power plants

    International Nuclear Information System (INIS)

    Kaiser, W.; Friedrich, H.; Knoefel, L.

    1985-01-01

    In order to meet the requirements of nuclear safety reactor components have to be designed aseismically. A model for studying simulated seismic effects on the reliability of containment equipment polar cranes is presented. Based on this model vertical and horizontal motions of the crane are investigated. Emphasis is laid on non-linearities caused by malfunctions such as lift of the crane from the runaway, lift of the trolley from the beams, slackening of the ropes as well as sliding of blocked track wheels. Seismic excitations are simulated by computer produced accelerograms

  16. Driving Interface Based on Tactile Sensors for Electric Wheelchairs or Trolleys

    Directory of Open Access Journals (Sweden)

    Andrés Trujillo-León

    2014-02-01

    Full Text Available This paper introduces a novel device based on a tactile interface to replace the attendant joystick in electric wheelchairs. It can also be used in other vehicles such as shopping trolleys. Its use allows intuitive driving that requires little or no training, so its usability is high. This is achieved by a tactile sensor located on the handlebar of the chair or trolley and the processing of the information provided by it. When the user interacts with the handle of the chair or trolley, he or she exerts a pressure pattern that depends on the intention to accelerate, brake or turn to the left or right. The electronics within the device then perform the signal conditioning and processing of the information received, identifying the intention of the user on the basis of this pattern using an algorithm, and translating it into control signals for the control module of the wheelchair. These signals are equivalent to those provided by a joystick. This proposal aims to help disabled people and their attendees and prolong the personal autonomy in a context of aging populations.

  17. Adams National Historic Park Trolley Vehicle Replacement Selection Analysis

    Science.gov (United States)

    2017-12-01

    Adams NHP owns three trolley vehicles that were purchased in the early 2000s and, while their accrued mileage remains low, they have reached the end of their useful lives due in large part to vehicle parts becoming unavailable. Both the original trol...

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

    Science.gov (United States)

    Kreutzer, Ingrid; Brückl, Ewald; Radinger, Alexander

    2015-04-01

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

  19. Seismic reliability assessment of RC structures including soil–structure interaction using wavelet weighted least squares support vector machine

    International Nuclear Information System (INIS)

    Khatibinia, Mohsen; Javad Fadaee, Mohammad; Salajegheh, Javad; Salajegheh, Eysa

    2013-01-01

    An efficient metamodeling framework in conjunction with the Monte-Carlo Simulation (MCS) is introduced to reduce the computational cost in seismic reliability assessment of existing RC structures. In order to achieve this purpose, the metamodel is designed by combining weighted least squares support vector machine (WLS-SVM) and a wavelet kernel function, called wavelet weighted least squares support vector machine (WWLS-SVM). In this study, the seismic reliability assessment of existing RC structures with consideration of soil–structure interaction (SSI) effects is investigated in accordance with Performance-Based Design (PBD). This study aims to incorporate the acceptable performance levels of PBD into reliability theory for comparing the obtained annual probability of non-performance with the target values for each performance level. The MCS method as the most reliable method is utilized to estimate the annual probability of failure associated with a given performance level in this study. In WWLS-SVM-based MCS, the structural seismic responses are accurately predicted by WWLS-SVM for reducing the computational cost. To show the efficiency and robustness of the proposed metamodel, two RC structures are studied. Numerical results demonstrate the efficiency and computational advantages of the proposed metamodel for the seismic reliability assessment of structures. Furthermore, the consideration of the SSI effects in the seismic reliability assessment of existing RC structures is compared to the fixed base model. It shows which SSI has the significant influence on the seismic reliability assessment of structures.

  20. A novel selection method of seismic attributes based on gray relational degree and support vector machine.

    Directory of Open Access Journals (Sweden)

    Yaping Huang

    Full Text Available The selection of seismic attributes is a key process in reservoir prediction because the prediction accuracy relies on the reliability and credibility of the seismic attributes. However, effective selection method for useful seismic attributes is still a challenge. This paper presents a novel selection method of seismic attributes for reservoir prediction based on the gray relational degree (GRD and support vector machine (SVM. The proposed method has a two-hierarchical structure. In the first hierarchy, the primary selection of seismic attributes is achieved by calculating the GRD between seismic attributes and reservoir parameters, and the GRD between the seismic attributes. The principle of the primary selection is that these seismic attributes with higher GRD to the reservoir parameters will have smaller GRD between themselves as compared to those with lower GRD to the reservoir parameters. Then the SVM is employed in the second hierarchy to perform an interactive error verification using training samples for the purpose of determining the final seismic attributes. A real-world case study was conducted to evaluate the proposed GRD-SVM method. Reliable seismic attributes were selected to predict the coalbed methane (CBM content in southern Qinshui basin, China. In the analysis, the instantaneous amplitude, instantaneous bandwidth, instantaneous frequency, and minimum negative curvature were selected, and the predicted CBM content was fundamentally consistent with the measured CBM content. This real-world case study demonstrates that the proposed method is able to effectively select seismic attributes, and improve the prediction accuracy. Thus, the proposed GRD-SVM method can be used for the selection of seismic attributes in practice.

  1. A "Neurological Emergency Trolley" reduces turnaround time for high-risk medications in a general intensive care unit.

    Science.gov (United States)

    Ajzenberg, Henry; Newman, Paula; Harris, Gail-Anne; Cranston, Marnie; Boyd, J Gordon

    2018-02-01

    To reduce medication turnaround times during neurological emergencies, a multidisciplinary team developed a neurological emergency crash trolley in our intensive care unit. This trolley includes phenytoin, hypertonic saline and mannitol, as well as other equipment. The aim of this study was to assess whether the cart reduced turnaround times for these medications. In this retrospective cohort study, medication delivery times for two year epochs before and after its implementation were compared. Eligible patients were identified from our intensive care unit screening log. Adults who required emergent use of phenytoin, hypertonic saline or mannitol while in the intensive care unit were included. Groups were compared with nonparametric analyses. 33-bed general medical-surgical intensive care unit in an academic teaching hospital. Time to medication administration. In the pre-intervention group, there were 43 patients with 66 events. In the post-intervention group, there were 45 patients with 80 events. The median medication turnaround time was significantly reduced after implementation of the neurological emergency trolley (25 vs. 10minutes, p=0.003). There was no statistically significant difference in intensive care or 30-day survival between the two cohorts. The implementation of a novel neurological emergency crash trolley in our intensive care unit reduced medication turnaround times. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Maintenance of working capacity of movement mechanism of load trolley with linear traction electric drive of bridge type crane.

    Science.gov (United States)

    Goncharov, K. A.; Denisov, I. A.

    2017-10-01

    The article considers the influence of the air gap size between the linear motor elements on the stability of the traction drive of the movement mechanism of the trolley of the bridge type crane. The main factors affecting the air gap size and the causes of their occurrence are described. The technique of calculating the magnitude of air gap variation is described in relation to the general deformation of the crane metal structure. Recommendations on the need for installation of additional equipment for load trolleys of various designs are given. The optimal values of the length of the trolley base are proposed. Observance of these values ensures normal operation of the traction drive.

  3. Non linear seismic analysis of charge/discharge machine

    International Nuclear Information System (INIS)

    Dostal, M.; Trbojevic, V.M.; Nobile, M.

    1987-01-01

    The main conclusions of the seismic analysis of the Latina CDM are: i. The charge machine has been demonstrated to be capable of withstanding the effects of a 0.1 g earthquake. Stresses and displacements were all within allowable limits and the stability criteria were fully satisfied for all positions of the cross-travel bogie on the gantry. ii. Movements due to loss of friction between the cross-travel bogie wheels and the rail was found to be small, i.e. less than 2 mm for all cases considered. The modes of rocking of the fixed and hinged legs preclude any possibility of excessive movement between the long travel bogie wheels and the rail. iii. The non-linear analysis incorporating contact and friction has given more realistic results than any of the linear verification analyses. The method of analysis indicates that even the larger structures can be efficiently solved on a mini computer for a long forcing input (16 s). (orig.)

  4. How practice contributes to trolley food waste. A qualitative study among staff involved in serving meals to hospital patients.

    Science.gov (United States)

    Ofei, K T; Holst, M; Rasmussen, H H; Mikkelsen, B E

    2014-12-01

    This study investigated the generation of trolley food waste at the ward level in a hospital in order to provide recommendations for how practice could be changed to reduce food waste. Three separate focus group discussions were held with four nurses, four dietitians and four service assistants engaged in food service. Furthermore, single qualitative interviews were conducted with a nurse, a dietitian and two service assistants. Observations of procedures around trolley food serving were carried out during lunch and supper for a total of 10 weekdays in two different wards. All unserved food items discarded as waste were weighed after each service. Analysis of interview and observation data revealed five key themes. The findings indicate that trolley food waste generation is a practice embedded within the limitations related to the procedures of meal ordering. This includes portion size choices and delivery, communication, tools for menu information, portioning and monitoring of food waste, as well as the use of unserved food. Considering positive changes to these can be a way forward to develop strategies to reduce trolley food waste at the ward level. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Disarming the Trolley Problem –Why Self-driving Cars do not Need to Choose Whom to Kill

    OpenAIRE

    Johansson , Rolf; Nilsson , Jonas

    2016-01-01

    International audience; Many claim that the “Trolley problem” is hindering the introduction of self-driving cars. Self-driving cars must, as all safety-critical products, be designed such that the probability of morally hard (“trolley”) situations is acceptably low. In this paper we argue that the introduction of self-driving cars can solve this ethical dilemma. In short the solution to the trolley problem is that a self-driving car must be able to estimate its own operational capability for ...

  6. Locating scatterers while drilling using seismic noise due to tunnel boring machine

    Science.gov (United States)

    Harmankaya, U.; Kaslilar, A.; Wapenaar, K.; Draganov, D.

    2018-05-01

    Unexpected geological structures can cause safety and economic risks during underground excavation. Therefore, predicting possible geological threats while drilling a tunnel is important for operational safety and for preventing expensive standstills. Subsurface information for tunneling is provided by exploratory wells and by surface geological and geophysical investigations, which are limited by location and resolution, respectively. For detailed information about the structures ahead of the tunnel face, geophysical methods are applied during the tunnel-drilling activity. We present a method inspired by seismic interferometry and ambient-noise correlation that can be used for detecting scatterers, such as boulders and cavities, ahead of a tunnel while drilling. A similar method has been proposed for active-source seismic data and validated using laboratory and field data. Here, we propose to utilize the seismic noise generated by a Tunnel Boring Machine (TBM), and recorded at the surface. We explain our method at the hand of data from finite-difference modelling of noise-source wave propagation in a medium where scatterers are present. Using the modelled noise records, we apply cross-correlation to obtain correlation gathers. After isolating the scattered arrivals in these gathers, we cross-correlate again and invert for the correlated traveltime to locate scatterers. We show the potential of the method for locating the scatterers while drilling using noise records due to TBM.

  7. The Trouble with Teaching Ethics on Trolley Cars and Train Tracks

    Science.gov (United States)

    Seider, Scott

    2009-01-01

    In this study, I investigate the beliefs of privileged adolescents about their obligations to those contending with hunger and poverty as well as the impact of "trolley problems" upon these adolescents' beliefs. To consider the attitudes of the young adults in this study, I draw upon their student writing from a course on social issues…

  8. Use seismic colored inversion and power law committee machine based on imperial competitive algorithm for improving porosity prediction in a heterogeneous reservoir

    Science.gov (United States)

    Ansari, Hamid Reza

    2014-09-01

    In this paper we propose a new method for predicting rock porosity based on a combination of several artificial intelligence systems. The method focuses on one of the Iranian carbonate fields in the Persian Gulf. Because there is strong heterogeneity in carbonate formations, estimation of rock properties experiences more challenge than sandstone. For this purpose, seismic colored inversion (SCI) and a new approach of committee machine are used in order to improve porosity estimation. The study comprises three major steps. First, a series of sample-based attributes is calculated from 3D seismic volume. Acoustic impedance is an important attribute that is obtained by the SCI method in this study. Second, porosity log is predicted from seismic attributes using common intelligent computation systems including: probabilistic neural network (PNN), radial basis function network (RBFN), multi-layer feed forward network (MLFN), ε-support vector regression (ε-SVR) and adaptive neuro-fuzzy inference system (ANFIS). Finally, a power law committee machine (PLCM) is constructed based on imperial competitive algorithm (ICA) to combine the results of all previous predictions in a single solution. This technique is called PLCM-ICA in this paper. The results show that PLCM-ICA model improved the results of neural networks, support vector machine and neuro-fuzzy system.

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

    Science.gov (United States)

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

    2014-05-01

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

  10. Nonlinear Methodologies for Identifying Seismic Event and Nuclear Explosion Using Random Forest, Support Vector Machine, and Naive Bayes Classification

    Directory of Open Access Journals (Sweden)

    Longjun Dong

    2014-01-01

    Full Text Available The discrimination of seismic event and nuclear explosion is a complex and nonlinear system. The nonlinear methodologies including Random Forests (RF, Support Vector Machines (SVM, and Naïve Bayes Classifier (NBC were applied to discriminant seismic events. Twenty earthquakes and twenty-seven explosions with nine ratios of the energies contained within predetermined “velocity windows” and calculated distance are used in discriminators. Based on the one out cross-validation, ROC curve, calculated accuracy of training and test samples, and discriminating performances of RF, SVM, and NBC were discussed and compared. The result of RF method clearly shows the best predictive power with a maximum area of 0.975 under the ROC among RF, SVM, and NBC. The discriminant accuracies of RF, SVM, and NBC for test samples are 92.86%, 85.71%, and 92.86%, respectively. It has been demonstrated that the presented RF model can not only identify seismic event automatically with high accuracy, but also can sort the discriminant indicators according to calculated values of weights.

  11. The Outcome and Patterns of Traumatic Brain Injury in the Paediatric Population of a Developing Country Secondary to TV Trolley Tip-Over.

    Science.gov (United States)

    Waqas, Muhammad; Javed, Gohar; Nathani, Karim Rizwan; Ujjan, Badar; Quadri, Syed A; Tahir, Muhammad Zubair

    2018-01-01

    Television (TV) trolley tip-over incidences are common and can cause significant morbidity and mortality in children. This study was aimed at analyzing the pattern and outcomes of head injuries resulting from TV trolley tip-over. We conducted a medical chart review of children with TV trolley tip-over head injuries from January 2009 to April 2016. We collected data on demographics, the mechanism of injury, clinical and radiological features of the injury, and outcomes. Outcomes were measured by means of the Glasgow Outcome Scale (GOS) at 6 months (except in 1 case). A descriptive analysis was carried out using SPSS v19. Twenty-two children were included in the study (median age 23.5 months). Sixteen children were male. Most of the children (n = 16) were aged 12-35 months. The median Glasgow Coma Scale score on admission was 15. The median Rotterdam Score for the patients was 2.0. Common symptoms upon admission were vomiting, irritability, scalp laceration, and bruises. Median length of hospital stay was 3 days. Skull bone fractures were present in 12 children. Other CT findings included contusions, extradural and subdural haematomas, intraventricular haemorrhage, and pneumocranium. Surgical intervention was required in 4 cases. Although most of the patients made a good recovery (GOS = 5), 1 patient developed a mild disability and another died in hospital. TV trolley tip-over is most common in toddlers and can lead to significant head injury and mortality. This can be avoided by parental supervision and adjustments in the household. © 2017 S. Karger AG, Basel.

  12. The ethics of accident-algorithms for self-driving cars: an applied trolley problem?

    OpenAIRE

    Nyholm, S.R.; Smids, J.

    2016-01-01

    Self-driving cars hold out the promise of being safer than manually driven cars. Yet they cannot be a 100 % safe. Collisions are sometimes unavoidable. So self-driving cars need to be programmed for how they should respond to scenarios where collisions are highly likely or unavoidable. The accident-scenarios self-driving cars might face have recently been likened to the key examples and dilemmas associated with the trolley problem. In this article, we critically examine this tempting analogy....

  13. Forced-choice decision-making in modified trolley dilemma situations: a virtual reality and eye tracking study.

    Science.gov (United States)

    Skulmowski, Alexander; Bunge, Andreas; Kaspar, Kai; Pipa, Gordon

    2014-01-01

    Based on the frameworks of dual-process theories, we examined the interplay between intuitive and controlled cognitive processes related to moral and social judgments. In a virtual reality (VR) setting we performed an experiment investigating the progression from fast, automatic decisions towards more controlled decisions over multiple trials in the context of a sacrificing scenario. We repeatedly exposed participants to a modified ten-to-one version and to three one-to-one versions of the trolley dilemma in VR and varied avatar properties, such as their gender and ethnicity, and their orientation in space. We also investigated the influence of arousing music on decisions. Our experiment replicated the behavioral pattern observed in studies using text versions of the trolley dilemma, thereby validating the use of virtual environments in research on moral judgments. Additionally, we found a general tendency towards sacrificing male individuals which correlated with socially desirable responding. As indicated by differences in response times, the ten-to-one version of the trolley dilemma seems to be faster to decide than decisions requiring comparisons based on specific avatar properties as a result of differing moral content. Building upon research on music-based emotion induction, we used music to induce emotional arousal on a physiological level as measured by pupil diameter. We found a specific temporal signature displaying a peak in arousal around the moment of decision. This signature occurs independently of the overall arousal level. Furthermore, we found context-dependent gaze durations during sacrificing decisions, leading participants to look prolonged at their victim if they had to choose between avatars differing in gender. Our study confirmed that moral decisions can be explained within the framework of dual-process theories and shows that pupillometric measurements are a promising tool for investigating affective responses in dilemma situations.

  14. Forced-choice decision-making in modified trolley dilemma situations: a virtual reality and eye tracking study

    Directory of Open Access Journals (Sweden)

    Alexander eSkulmowski

    2014-12-01

    Full Text Available Based on the frameworks of dual-process theories, we examined the interplay between intuitive and controlled cognitive processes related to moral and social judgments. In a virtual reality setting we performed an experiment investigating the progression from fast, automatic decisions towards more controlled decisions over multiple trials in the context of a sacrificing scenario. We repeatedly exposed participants to a modified ten-to-one version and to three one-to-one versions of the trolley dilemma in virtual reality and varied avatar properties, such as their gender and ethnicity, and their orientation in space. We also investigated the influence of arousing music on decisions. Our experiment replicated the behavioral pattern observed in studies using text versions of the trolley dilemma, thereby validating the use of virtual environments in research on moral judgments. Additionally, we found a general tendency towards sacrificing male individuals which correlated with socially desirable responding. As indicated by differences in response times, the ten-to-one version of the trolley dilemma seems to be faster to decide than decisions requiring comparisons based on specific avatar properties as a result of differing moral content. Building upon research on music-based emotion induction, we used music to induce emotional arousal on a physiological level as measured by pupil diameter. We found a specific temporal signature displaying a peak in arousal around the moment of decision. This signature occurs independently of the overall arousal level. Furthermore, we found context-dependent gaze durations during sacrificing decisions, leading participants to look prolonged at their victim if they had to choose between avatars differing in gender. Our study confirmed that moral decisions can be explained within the framework of dual-process theories and shows that pupillometric measurements are a promising tool for investigating affective responses in

  15. Seismic isolation floor and vibration control equipment for nuclear power plant

    International Nuclear Information System (INIS)

    Niwa, H.; Fujimoto, S.; Aida, Y.; Miyano, H.

    1996-01-01

    We have developed a seismic isolation floor to improve protection against earthquakes for process computer systems, and a magnetic dynamic damper to reduce the mechanical vibrations of piping systems and pumps in nuclear power plants. Seismic excitation tests of the seismic isolation floor, on which process computer systems were installed, were performed using large earthquake simulators. The test results proved that the seismic isolation floor significantly reduced seismic forces. To control mechanical vibrations, a magnetic dynamic damper was designed using permanent magnets. This magnetic dynamic damper does not require mechanical springs, dampers and supports in the floors and walls of the building. Vibration tests using a rotating machine model confirmed that the magnetic dynamic damper effectively controlled vibrations in such a rotating machine model. (author)

  16. Clostridium difficile in retail baskets, trolleys, conveyor belts, and plastic bags in Saudi Arabia.

    Science.gov (United States)

    Alqumber, Mohammed A

    2014-10-01

    To determine Clostridium difficile (C. difficile) prevalence on retail surfaces and shoppers plastic bags. From 20 June to 10 August 2011, in a cross-sectional epidemiological study, 17 supermarkets from 2 cities, Albaha and Altaif, Saudi Arabia were sampled. A total of 800 samples, which comprised 200 samples per surveyed surface, were studied. These included baskets, trolleys, conveyer belts, and outgoing shoppers' plastic bags. Clostridium difficile strains were isolated. The isolates were characterized using ribotyping and  polymerase chain reaction for the detection of toxin A (tcdA), toxin B (tcdB), binary toxin (cdtB), and toxin C (tcdC) genes. Susceptibility to antibiotics was determined on a Muller-Hinton agar with 5% sheep blood agar using E-tests. Overall, the C. difficile prevalence on sampled surfaces was 0.75%. The highest prevalence was found on retail baskets and trolleys, followed by plastic bags. A total of 5 different ribotypes were identified. Alterations in tcdC were detected in ribotype 027 and BT1. All the identified isolates were susceptible to vancomycin, but resistant to levofloxacin. In this study, C. difficile was present at a rate of 0.75% on supermarket surfaces. Spore disinfection of implicated surfaces may be necessary to control any community-acquired infections caused by this pathogen. 

  17. Discriminating Induced-Microearthquakes Using New Seismic Features

    Science.gov (United States)

    Mousavi, S. M.; Horton, S.

    2016-12-01

    We studied characteristics of induced-microearthquakes on the basis of the waveforms recorded on a limited number of surface receivers using machine-learning techniques. Forty features in the time, frequency, and time-frequency domains were measured on each waveform, and several techniques such as correlation-based feature selection, Artificial Neural Networks (ANNs), Logistic Regression (LR) and X-mean were used as research tools to explore the relationship between these seismic features and source parameters. The results show that spectral features have the highest correlation to source depth. Two new measurements developed as seismic features for this study, spectral centroids and 2D cross-correlations in the time-frequency domain, performed better than the common seismic measurements. These features can be used by machine learning techniques for efficient automatic classification of low energy signals recorded at one or more seismic stations. We applied the technique to 440 microearthquakes-1.7Reference: Mousavi, S.M., S.P. Horton, C. A. Langston, B. Samei, (2016) Seismic features and automatic discrimination of deep and shallow induced-microearthquakes using neural network and logistic regression, Geophys. J. Int. doi: 10.1093/gji/ggw258.

  18. Performance Analysis on Transfer Platforms in Frame Bridge Based Automated Container Terminals

    Directory of Open Access Journals (Sweden)

    Hongtao Hu

    2013-01-01

    Full Text Available This paper studies a new automated container terminal (ACT system which utilizes multistory frame bridges and rail-mounted trolleys to transport containers between the quay and the yard. Beside typical ACT systems use trucks or automated guided vehicles for transporting containers between quay cranes and yard cranes, the new design uses three types of handling machines, namely, ground trolleys (GTs, transfer platforms (TPs, and frame trolleys (FTs. These three types of handling machines collaborate with one another to transport containers. This study decomposes the system into several subsystems. Each subsystem has one TP and several FTs and GTs dedicated to this TP. Then, a Markov chain model is developed to analyze the throughput of TPs. At last, the performance of the new ACT system is estimated. Sensitivity analyzes the numbers, and the processing rates of trolleys are conducted through the numeric experiments.

  19. Framing Effect in the Trolley Problem and Footbridge Dilemma.

    Science.gov (United States)

    Cao, Fei; Zhang, Jiaxi; Song, Lei; Wang, Shoupeng; Miao, Danmin; Peng, Jiaxi

    2017-02-01

    The present study investigated the effect of dilemma type, framing, and number of saved lives on moral decision making. A total of 591 undergraduates, with a mean age of 20.56 (SD = 1.37) were randomly assigned to 12 groups on the basis of a grid of two dilemma types (the trolley problem or the footbridge dilemma) by three frames (positive, neutral, or negative frame) by two different numbers of workers (5 or 15 people). The main effects of dilemma type, frame, and number of saved workers were all significant. The interaction of dilemma type and number of saved workers and the interaction of the three independent factors were significant. Results indicated that moral judgment is affected by framing. Specifically, people were more inclined to utilitarianism in the positive or neutral frame and more inclined to intuitionism in the negative frame. Furthermore, this effect can be moderated by dilemma type and number of saved lives. Implications of our results are discussed.

  20. Seismic analysis during development stage of CANDU Model 2 fueling machine design

    International Nuclear Information System (INIS)

    Lee, L.S.S.; Mansfield, R.A.

    1989-01-01

    The CANDU Model 3 is a new small reactor presently being designed. This reactor is 450 MWe, and as with current operating CANDU's, is based on a heavy water moderated and cooled system using on-power fuelling for the once-through natural uranium fuel cycle. The CANDU 3 Standard plant is designed to be adaptable to a range of world-wide site conditions, i.e. for a peak ground acceleration of 0.3 g and a wide range of soft, medium and hard foundation medium properties. Consequently, a conservatism in the design of structure and equipment is accounted by using enveloped floor response spectra generated by the soil-structure interaction analysis. Seismic qualification of the fuelling machine (F/M) and its support structure are an essential design requirement for maintaining the integrity of the reactor coolant heat transport system (HTS) pressure boundary and the service ports penetrating the containment structure during on-power fueling. This paper deals with the initial conceptual phase of design where the details of the design are in fundamental outline form only and basic mass distribution plus layout geometry is defined

  1. Dynamic analysis of the BPX machine structure

    International Nuclear Information System (INIS)

    Dahlgen, F.; Citrolo, J.; Knutson, D.; Kalish, M.

    1992-01-01

    A preliminary analysis of the response of the BPX machine structure to a seismic input was performed. MSC/NASTRAN 5 , a general purpose XXX element computer code, has been used. The purpose of this paper is to assess the probable range of seismically induced stresses and deflections in the machine substructure which connects the machine to the test cell floor, with particular emphasis on the shear pins which will be used to attach the TF coil modules to the machine substructure (for a more detailed description of the shear pins and structure see ref. 4 in these proceedings). The model was developed with sufficient detail to be used subsequently to investigate the transient response to various dynamic loading conditions imposed on the structure by the PF, TF, and Vacuum Vessel, during normal and off-normal operations. The model does not include the mass and stiffness of the building or the building-soil interaction and as such can only be considered an interim assessment of the dynamic response of the machine to the S.S.E.(this is the Safe Shutdown Earthquake which is also the Design XXX Earthquake for all major structural components)

  2. Simultaneous multi-component seismic denoising and reconstruction via K-SVD

    Science.gov (United States)

    Hou, Sian; Zhang, Feng; Li, Xiangyang; Zhao, Qiang; Dai, Hengchang

    2018-06-01

    Data denoising and reconstruction play an increasingly significant role in seismic prospecting for their value in enhancing effective signals, dealing with surface obstacles and reducing acquisition costs. In this paper, we propose a novel method to denoise and reconstruct multicomponent seismic data simultaneously. This method lies within the framework of machine learning and the key points are defining a suitable weight function and a modified inner product operator. The purpose of these two processes are to perform missing data machine learning when the random noise deviation is unknown, and building a mathematical relationship for each component to incorporate all the information of multi-component data. Two examples, using synthetic and real multicomponent data, demonstrate that the new method is a feasible alternative for multi-component seismic data processing.

  3. Multi Canister Overpack (MCO) Handling Machine - Independent Review of Seismic Structural Analysis

    International Nuclear Information System (INIS)

    SWENSON, C.E.

    2000-01-01

    The following separate reports and correspondence pertains to the independent review of the seismic analysis. The original analysis was performed by GEC-Alsthom Engineering Systems Limited (GEC-ESL) under subcontract to Foster-Wheeler Environmental Corporation (FWEC) who was the prime integration contractor to the Spent Nuclear Fuel Project for the Multi-Canister Overpack (MCO) Handling Machine (MHM). The original analysis was performed to the Design Basis Earthquake (DBE) response spectra using 5% damping as required in specification, HNF-S-0468 for the 90% Design Report in June 1997. The independent review was performed by Fluor-Daniel (Irvine) under a separate task from their scope as Architect-Engineer of the Canister Storage Building (CSB) in 1997. The comments were issued in April 1998. Later in 1997, the response spectra of the Canister Storage Building (CSB) was revised according to a new soil-structure interaction analysis and accordingly revised the response spectra for the MHM and utilized 7% damping in accordance with American Society of Mechanical Engineers (ASME) NOG-1, ''Rules for Construction of Overhead and Gantry Cranes (Top Running Bridge, Multiple Girder).'' The analysis was re-performed to check critical areas but because manufacturing was underway, designs were not altered unless necessary. FWEC responded to SNF Project correspondence on the review comments in two separate letters enclosed. The dispositions were reviewed and accepted. Attached are supplier source surveillance reports on the procedures and process by the engineering group performing the analysis and structural design. All calculation and analysis results are contained in the MHM Final Design Report which is part of the Vendor Information File 50100. Subsequent to the MHM supplier engineering analysis, there was a separate analyses for nuclear safety accident concerns that used the electronic input data files provided by FWEC/GEC-ESL and are contained in document SNF-6248

  4. Multi Canister Overpack (MCO) Handling Machine Independent Review of Seismic Structural Analysis

    Energy Technology Data Exchange (ETDEWEB)

    SWENSON, C.E.

    2000-09-22

    The following separate reports and correspondence pertains to the independent review of the seismic analysis. The original analysis was performed by GEC-Alsthom Engineering Systems Limited (GEC-ESL) under subcontract to Foster-Wheeler Environmental Corporation (FWEC) who was the prime integration contractor to the Spent Nuclear Fuel Project for the Multi-Canister Overpack (MCO) Handling Machine (MHM). The original analysis was performed to the Design Basis Earthquake (DBE) response spectra using 5% damping as required in specification, HNF-S-0468 for the 90% Design Report in June 1997. The independent review was performed by Fluor-Daniel (Irvine) under a separate task from their scope as Architect-Engineer of the Canister Storage Building (CSB) in 1997. The comments were issued in April 1998. Later in 1997, the response spectra of the Canister Storage Building (CSB) was revised according to a new soil-structure interaction analysis and accordingly revised the response spectra for the MHM and utilized 7% damping in accordance with American Society of Mechanical Engineers (ASME) NOG-1, ''Rules for Construction of Overhead and Gantry Cranes (Top Running Bridge, Multiple Girder).'' The analysis was re-performed to check critical areas but because manufacturing was underway, designs were not altered unless necessary. FWEC responded to SNF Project correspondence on the review comments in two separate letters enclosed. The dispositions were reviewed and accepted. Attached are supplier source surveillance reports on the procedures and process by the engineering group performing the analysis and structural design. All calculation and analysis results are contained in the MHM Final Design Report which is part of the Vendor Information File 50100. Subsequent to the MHM supplier engineering analysis, there was a separate analyses for nuclear safety accident concerns that used the electronic input data files provided by FWEC/GEC-ESL and are contained in

  5. Relays undergo seismic tests

    International Nuclear Information System (INIS)

    Burton, J.C.

    1977-01-01

    Utilities are required by the Nuclear Regulatory Commission to document that seismic vibration will not adversely affect critical electrical equipment. Seismic testing should be designed to determine the malfunction level (fragility testing). Input possibilities include a continuous sine, a decaying sine, a sine beat, random vibrations, and combinations of random vibrations and sine beat. The sine beat most accurately simulates a seismic event. Test frequencies have a broad range in order to accommodate a variety of relay types and cabinet mounting. Simulation of motion along three axes offers several options, but is best achieved by three in-phase single-axis vibration machines that are less likely to induce testing fatigue failure. Consensus on what constitutes relay failure favors a maximum two microsecond discontinuity. Performance tests should be conducted for at least two of the following: (1) nonoperating modes, (2) operating modes, or (3) the transition above the two modes, with the monitoring mode documented for all three. Results should specify a capability curve of maximum safe seismic acceleration and a graph plotting acceleration with sine-beat frequency

  6. Improved Seismic Acquisition System and Data Processing for the Italian National Seismic Network

    Science.gov (United States)

    Badiali, L.; Marcocci, C.; Mele, F.; Piscini, A.

    2001-12-01

    A new system for acquiring and processing digital signals has been developed in the last few years at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). The system makes extensive use of the internet communication protocol standards such as TCP and UDP which are used as the transport highway inside the Italian network, and possibly in a near future outside, to share or redirect data among processes. The Italian National Seismic Network has been working for about 18 years equipped with vertical short period seismometers and transmitting through analog lines, to the computer center in Rome. We are now concentrating our efforts on speeding the migration towards a fully digital network based on about 150 stations equipped with either broad band or 5 seconds sensors connected to the data center partly through wired digital communication and partly through satellite digital communication. The overall process is layered through intranet and/or internet. Every layer gathers data in a simple format and provides data in a processed format, ready to be distributed towards the next layer. The lowest level acquires seismic data (raw waveforms) coming from the remote stations. It handshakes, checks and sends data in LAN or WAN according to a distribution list where other machines with their programs are waiting for. At the next level there are the picking procedures, or "pickers", on a per instrument basis, looking for phases. A picker spreads phases, again through the LAN or WAN and according to a distribution list, to one or more waiting locating machines tuned to generate a seismic event. The event locating procedure itself, the higher level in this stack, can exchange information with other similar procedures. Such a layered and distributed structure with nearby targets allows other seismic networks to join the processing and data collection of the same ongoing event, creating a virtual network larger than the original one. At present we plan to cooperate with other

  7. Seismic review of vault for MFTF upgrade project

    International Nuclear Information System (INIS)

    Franklin, H.A.

    1983-01-01

    This letter report was prepared in accordance with the scope of work for the preconceptual seismic evaluation of the (α + T) Tandem Mirror Fusion Machine concrete vault. The scope of the work was developed with the assistance of the Bechtel site representative Dr. Sunil Ghose. The report contains comments and preconceptual recommendations on wall upgrading for an 150-ton crane installation, concrete vault seismic capability for (α + T) conditions, and recommendations for future work

  8. Trust, trolleys and social dilemmas: A replication study.

    Science.gov (United States)

    Bostyn, Dries H; Roets, Arne

    2017-05-01

    The present manuscript addresses how perceived trustworthiness of cooperative partners in a social dilemma context is influenced by the moral judgments those partners make on Trolley-type moral dilemmas; an issue recently investigated by Everett, Pizarro, and Crockett (2016). The present research comprises 2 studies that were conducted independently, simultaneously with, and incognizant of the Everett studies. Whereas the present studies aimed at investigating the same research hypothesis, a different and more elaborate methodology was used, as such providing a conceptual replication opportunity and extension to the Everett et al. Overall, the present studies clearly confirmed the main finding of Everett et al., that deontologists are more trusted than consequentialists in social dilemma games. Study 1 replicates Everett et al.'s effect in the context of trust games. Study 2 generalizes the effect to public goods games, thus demonstrating that it is not specific to the type of social dilemma game used in Everett et al. Finally, both studies build on these results by demonstrating that the increased trust in deontologists may sometimes, but not always, be warranted: deontologists displayed increased cooperation rates but only in the public goods game and not in trust games. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Specific issues for seismic performance of power plant equipment

    Energy Technology Data Exchange (ETDEWEB)

    Nawrotzki, Peter [GERB Vibration Control Systems, Berlin (Germany)

    2010-01-15

    Power plant machinery can be dynamically decoupled from the substructure by the effective use of helical steel springs and viscous dampers. Turbine foundations, coal mills, boiler feed pumps and other machine foundations benefit from this type of elastic support systems to mitigate the transmission of operational vibration. The application of these devices may also be used to protect against earthquakes and other catastrophic events, i.e. airplane crash, of particular importance in nuclear facilities. This article illustrates basic principles of elastic support systems and applications on power plant equipment and buildings in medium and high seismic areas. Spring damper combinations with special stiffness properties are used to reduce seismic acceleration levels of turbine components and other safety or non-safety related structures. For turbine buildings, the integration of the turbine sub-structure into the machine building can further reduce stress levels in all structural members. The application of this seismic protection strategy for a spent fuel storage tank in a high seismic area is also discussed. Safety in nuclear facilities is of particular importance and recent seismic events and the resulting damage in these facilities again brings up the discussion. One of the latest events is the 2007 Chuetsu earthquake in Japan. The resulting damage in the Kashiwazaki Kariwa Nuclear Power Plant can be found in several reports, e.g. in Yamashita. (orig.)

  10. First SPS magnets installed

    CERN Document Server

    1974-01-01

    On October 18, 1974 the first quadrupole (8 ton) on its trolley was taken down in the lift of PA3 and then towed to its place near shaft PP4. It was lifted off the trolley by a special machine provided with arms. (See CERN Weekly Bulletin of week 44 and Photo Archive 7410287)

  11. Method to Increase the Coupling Force in a Construction Machine

    Directory of Open Access Journals (Sweden)

    Tsipurskij Il’ja

    2017-01-01

    Full Text Available This paper discusses a possible method to increase the coupling tractive force track-wheel locomotion of construction machines. Sufficient tractive coupling force allows organizing translational displacement of the machine under above-medium load modes during operation of overburden chain excavators, tower cranes and gantry cranes in outdoors environments. A mechanism is examined to convert rotary motion into rectilinear motion using the example of a gear and rail, with kinematic calculations quoted. Analysis of the “force couple” system is proposed to identify free traction forces. Factors are established that influence the machine’s working movements. Equations to calculate tractive forces in track-wheel locomotion are described. A laboratory complex is presented where students of mechanical engineering gain practical skills in mastering the production process of soil excavation and the influence of the coupling tractive force during the machine’s operation. As practical recommendation, the paper describes a device made of a balancing lever, drive cogwheel and tractive chain to implement the required tractive force of the trolley in coupling; this solution’s efficiency is demonstrated for experimental works on hard soils with high coefficient of difficulty.

  12. Virtual morality: emotion and action in a simulated three-dimensional "trolley problem".

    Science.gov (United States)

    Navarrete, C David; McDonald, Melissa M; Mott, Michael L; Asher, Benjamin

    2012-04-01

    Experimentally investigating the relationship between moral judgment and action is difficult when the action of interest entails harming others. We adopt a new approach to this problem by placing subjects in an immersive, virtual reality environment that simulates the classic "trolley problem." In this moral dilemma, the majority of research participants behaved as "moral utilitarians," either (a) acting to cause the death of one individual in order to save the lives of five others, or (b) abstaining from action, when that action would have caused five deaths versus one. Confirming the emotional distinction between moral actions and omissions, autonomic arousal was greater when the utilitarian outcome required action, and increased arousal was associated with a decreased likelihood of utilitarian-biased behavior. This pattern of results held across individuals of different gender, age, and race. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  13. Seismic prediction ahead of tunnel construction using Rayleigh-waves

    OpenAIRE

    Jetschny, Stefan; De Nil, Denise; Bohlen, Thomas

    2008-01-01

    To increase safety and efficiency of tunnel constructions, online seismic exploration ahead of a tunnel can become a valuable tool. We developed a new forward looking seismic imaging technique e.g. to determine weak and water bearing zones ahead of the constructions. Our approach is based on the excitation and registration of tunnel surface-waves. These waves are excited at the tunnel face behind the cutter head of a tunnel boring machine and travel into drilling direction. Arriving at the fr...

  14. Automatic Classification of volcano-seismic events based on Deep Neural Networks.

    Science.gov (United States)

    Titos Luzón, M.; Bueno Rodriguez, A.; Garcia Martinez, L.; Benitez, C.; Ibáñez, J. M.

    2017-12-01

    Seismic monitoring of active volcanoes is a popular remote sensing technique to detect seismic activity, often associated to energy exchanges between the volcano and the environment. As a result, seismographs register a wide range of volcano-seismic signals that reflect the nature and underlying physics of volcanic processes. Machine learning and signal processing techniques provide an appropriate framework to analyze such data. In this research, we propose a new classification framework for seismic events based on deep neural networks. Deep neural networks are composed by multiple processing layers, and can discover intrinsic patterns from the data itself. Internal parameters can be initialized using a greedy unsupervised pre-training stage, leading to an efficient training of fully connected architectures. We aim to determine the robustness of these architectures as classifiers of seven different types of seismic events recorded at "Volcán de Fuego" (Colima, Mexico). Two deep neural networks with different pre-training strategies are studied: stacked denoising autoencoder and deep belief networks. Results are compared to existing machine learning algorithms (SVM, Random Forest, Multilayer Perceptron). We used 5 LPC coefficients over three non-overlapping segments as training features in order to characterize temporal evolution, avoid redundancy and encode the signal, regardless of its duration. Experimental results show that deep architectures can classify seismic events with higher accuracy than classical algorithms, attaining up to 92% recognition accuracy. Pre-training initialization helps these models to detect events that occur simultaneously in time (such explosions and rockfalls), increase robustness against noisy inputs, and provide better generalization. These results demonstrate deep neural networks are robust classifiers, and can be deployed in real-environments to monitor the seismicity of restless volcanoes.

  15. Processing of seismic signals from a seismometer network

    International Nuclear Information System (INIS)

    Key, F.A.; Warburton, P.J.

    1983-08-01

    A description is given of the Seismometer Network Analysis Computer (SNAC) which processes short period data from a network of seismometers (UKNET). The nine stations of the network are distributed throughout the UK and their outputs are transmitted to a control laboratory (Blacknest) where SNAC monitors the data for seismic signals. The computer gives an estimate of the source location of the detected signals and stores the waveforms. The detection logic is designed to maintain high sensitivity without excessive ''false alarms''. It is demonstrated that the system is able to detect seismic signals at an amplitude level consistent with a network of single stations and, within the limitations of signal onset time measurements made by machine, can locate the source of the seismic disturbance. (author)

  16. Estimating Fault Friction From Seismic Signals in the Laboratory

    Science.gov (United States)

    Rouet-Leduc, Bertrand; Hulbert, Claudia; Bolton, David C.; Ren, Christopher X.; Riviere, Jacques; Marone, Chris; Guyer, Robert A.; Johnson, Paul A.

    2018-02-01

    Nearly all aspects of earthquake rupture are controlled by the friction along the fault that progressively increases with tectonic forcing but in general cannot be directly measured. We show that fault friction can be determined at any time, from the continuous seismic signal. In a classic laboratory experiment of repeating earthquakes, we find that the seismic signal follows a specific pattern with respect to fault friction, allowing us to determine the fault's position within its failure cycle. Using machine learning, we show that instantaneous statistical characteristics of the seismic signal are a fingerprint of the fault zone shear stress and frictional state. Further analysis of this fingerprint leads to a simple equation of state quantitatively relating the seismic signal power and the friction on the fault. These results show that fault zone frictional characteristics and the state of stress in the surroundings of the fault can be inferred from seismic waves, at least in the laboratory.

  17. Seismic monitoring of the Yucca Mountain facility

    International Nuclear Information System (INIS)

    Garbin, H.D.; Herrington, P.B.; Kromer, R.P.

    1997-01-01

    Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals.) The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository's southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in signal detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM

  18. CANDU 9 fuelling machine carriage

    Energy Technology Data Exchange (ETDEWEB)

    Ullrich, D J; Slavik, J F [Atomic Energy of Canada Ltd., Saskatoon, SK (Canada)

    1997-12-31

    Continuous, on-power refuelling is a key feature of all CANDU reactor designs and is essential to maintaining high station capacity factors. The concept of a fuelling machine carriage can be traced to the early CANDU designs, such as the Douglas Point Nuclear Generating Station. In the CANDU 9 480NU unit, the combination of a mobile carriage and a proven fuelling machine head design comprises an effective means of transporting fuel between the reactor and the fuel transfer ports. It is a suitable alternative to the fuelling machine bridge system that has been utilized in the CANDU 6 reactor units. The CANDU 9 480NU fuel handling system successfully combines features that meet the project requirements with respect to fuelling performance, functionality, seismic qualification and the use of proven components. The design incorporates improvements based on experience and applicable current technologies. (author). 4 figs.

  19. CANDU 9 fuelling machine carriage

    International Nuclear Information System (INIS)

    Ullrich, D.J.; Slavik, J.F.

    1996-01-01

    Continuous, on-power refuelling is a key feature of all CANDU reactor designs and is essential to maintaining high station capacity factors. The concept of a fuelling machine carriage can be traced to the early CANDU designs, such as the Douglas Point Nuclear Generating Station. In the CANDU 9 480NU unit, the combination of a mobile carriage and a proven fuelling machine head design comprises an effective means of transporting fuel between the reactor and the fuel transfer ports. It is a suitable alternative to the fuelling machine bridge system that has been utilized in the CANDU 6 reactor units. The CANDU 9 480NU fuel handling system successfully combines features that meet the project requirements with respect to fuelling performance, functionality, seismic qualification and the use of proven components. The design incorporates improvements based on experience and applicable current technologies. (author). 4 figs

  20. Electric converters of electromagnetic strike machine with capacitor supply

    Science.gov (United States)

    Usanov, K. M.; Volgin, A. V.; Kargin, V. A.; Moiseev, A. P.; Chetverikov, E. A.

    2018-03-01

    The application of pulse linear electromagnetic engines in small power strike machines (energy impact is 0.01...1.0 kJ), where the characteristic mode of rare beats (pulse seismic vibrator, the arch crash device bins bulk materials), is quite effective. At the same time, the technical and economic performance of such machines is largely determined by the ability of the power source to provide a large instantaneous power of the supply pulses in the winding of the linear electromagnetic motor. The use of intermediate energy storage devices in power systems of rare-shock LEME makes it possible to obtain easily large instantaneous powers, forced energy conversion, and increase the performance of the machine. A capacitor power supply of a pulsed source of seismic waves is proposed for the exploration of shallow depths. The sections of the capacitor storage (CS) are connected to the winding of the linear electromagnetic motor by thyristor dischargers, the sequence of activation of which is determined by the control device. The charge of the capacitors to the required voltage is made directly from the battery source, or through the converter from a battery source with a smaller number of batteries.

  1. Seismic Waveform Inversion : Bump functional, parameterization analysis and imaging ahead of a tunnel-boring machine

    NARCIS (Netherlands)

    Pisupati, P.B.

    2017-01-01

    During a seismic experiment, mechanical waves are usually generated by various manmade sources. These waves propagate in the subsurface and are recorded at receivers. Modern seismic exploration methods analyze them to infer the mechanical properties of the subsurface; this is commonly referred as

  2. Universal delivery machine - design of the Bruce and Darlington heads

    International Nuclear Information System (INIS)

    Gray, M.G.; Brown, R.

    2003-01-01

    The Universal Delivery Machine (UDM) was designed and supplied to reduce the time required to perform channel inspection services. The Bruce UDM was the first to be completed followed by Pickering and Darlington. The Bruce and Darlington machines are nearly identical. Design concepts applied include a rotating, multiple tool station magazine, a rigid chain driving telescoping rams, a common drive package, and an external support frame to meet seismic qualification requirements. (author)

  3. Man-caused seismicity of Kuzbass

    Science.gov (United States)

    Emanov, Alexandr; Emanov, Alexey; Leskova, Ekaterina; Fateyev, Alexandr

    2010-05-01

    A natural seismicity of Kuznetsk Basin is confined in the main to mountain frame of Kuznetsk hollow. In this paper materials of experimental work with local station networks within sediment basin are presented. Two types of seismicity display within Kuznetsk hollow have been understood: first, man-caused seismic processes, confined to mine working and concentrated on depths up to one and a half of km; secondly, seismic activations on depths of 2-56 km, not coordinated in plan with coal mines. Every of studied seismic activations consists of large quantity of earthquakes of small powers (Ms=1-3). From one to first tens of earthquakes were recorded in a day. The earthquakes near mine working shift in space along with mine working, and seismic process become stronger at the instant a coal-plough machine is operated, and slacken at the instant the preventive works are executed. The seismic processes near three lavas in Kuznetsk Basin have been studied in detail. Uplift is the most typical focal mechanism. Activated zone near mine working reach in diameter 1-1,5 km. Seismic activations not linked with mine working testify that the subsoil of Kuznetsk hollow remain in stress state in whole. The most probable causes of man-caused action on hollow are processes, coupled with change of physical state of rocks at loss of methane from large volume or change by mine working of rock watering in large volume. In this case condensed rocks, lost gas and water, can press out upwards, realizing the reverse fault mechanism of earthquakes. A combination of stress state of hollow with man-caused action at deep mining may account for incipient activations in Kuznetsk Basin. Today earthquakes happen mainly under mine workings, though damages of workings themselves do not happen, but intensive shaking on surface calls for intent study of so dangerous phenomena. In 2009 replicates of the experiment on research of seismic activations in area of before investigated lavas have been conducted

  4. Mapping of contamination at Savannah River Site FBWU by INEEL trolley

    International Nuclear Information System (INIS)

    Carpenter, M.V.; Gehrke, R.J.; Helmer, R.G.; Josten, N.

    1998-01-01

    The Ford Building Waste Unit (FBWU) 643-11G is a Resource Conservation and Recovery Act/Comprehensive Environmental Response Compensation and Liability Act (RCRA/CERCLA) designated site at the Savannah River Site (SRS) in Aiken, South Carolina. Pre-Work Plan Characterization at the FBWU in May 1996 indicated that radiological contamination was present in surface and near surface soils and identified cesium-137, 137 Cs, the unit specific contaminant, as being primarily in the top 15 cm of soil. The Idaho National Engineering and Environmental Laboratory (INEEL) sent the dig-face trolley system to SRS where it demonstrated its capability over a 6.1-m (20 ft.) x 9.6-m (30 ft.) area to rapidly map the contamination on-line with its large area plastic scintillation detector. Also, an extended-range (10 keV to 3 MeV) Ge detector was used at selected locations to identify and quantify the 137 Cs contamination. The coordinate locations of each measurement acquired in either the scanning or fixed position mode was obtained with a survey system based on radial encoders. Topography measurements were also made during measurements to permit correction of field of view and activity concentrations for changes in the ground to detector distance

  5. Design and development of the CRBRP ex-vessel transfer machine

    International Nuclear Information System (INIS)

    Jones, C.E. Jr.

    1977-01-01

    The Reactor Refueling System (RRS) for the Clinch River Breeder Reactor Project (CRBRP) uses the Ex-Vessel Transfer Machine (EVTM) for transferring core assemblies outside the reactor vessel. The design of the Ex-Vessel Transfer Machine (EVTM) and its gantry-trolly for the CRBRP is discussed. The development tests required for the design are presented, in conjunction with the impact of the test results on the design. The impact of the increased seismic requirements on the design are also presented

  6. Prediction of tunnel boring machine performance using machine and rock mass data

    International Nuclear Information System (INIS)

    Dastgir, G.

    2012-01-01

    Performance of the tunnel boring machine and its prediction by different methods has been a hot issue since the first TBM came into being. For the sake of safe and sound transport, improvement of hydro-power, mining, civil and many other tunneling projects that cannot be driven efficiently and economically by conventional drill and blast, TBMs are quite frequently used. TBM parameters and rock mass properties, which heavily influence machine performance, should be estimated or known before choice of TBM-type and start of excavation. By applying linear regression analysis (SPSS19), fuzzy logic tools and a special Math-Lab code on actual field data collected from seven TBM driven tunnels (Hieflau expansion, Queen water tunnel, Vereina, Hemerwald, Maen, Pieve and Varzo tunnel), an attempt was made to provide prediction of rock mass class (RMC), rock fracture class (RFC), penetration rate (PR) and advance rate (AR). For detailed analysis of TBM performance, machine parameters (thrust, machine rpm, torque, power etc.), machine types and specification and rock mass properties (UCS, discontinuity in rock mass, RMC, RFC, RMR, etc.) were analyzed by 3-D surface plotting using statistical software R. Correlations between machine parameters and rock mass properties which effectively influence prediction models, are presented as well. In Hieflau expansion tunnel AR linearly decreases with increase of thrust due to high dependence of machine advance rate upon rock strength. For Hieflau expansion tunnel three types of data (TBM, rock mass and seismic data e.g. amplitude, pseudo velocity etc.) were coupled and simultaneously analyzed by plotting 3-D surfaces. No appreciable correlation between seismic data (Amplitude and Pseudo velocity) and rock mass properties and machine parameters could be found. Tool wear as a function of TBM operational parameters was analyzed which revealed that tool wear is minimum if applied thrust is moderate and that tool wear is high when thrust is

  7. Coupling a Basin Modeling and a Seismic Code using MOAB

    KAUST Repository

    Yan, Mi; Jordan, Kirk; Kaushik, Dinesh; Perrone, Michael; Sachdeva, Vipin; Tautges, Timothy J.; Magerlein, John

    2012-01-01

    We report on a demonstration of loose multiphysics coupling between a basin modeling code and a seismic code running on a large parallel machine. Multiphysics coupling, which is one critical capability for a high performance computing (HPC) framework, was implemented using the MOAB open-source mesh and field database. MOAB provides for code coupling by storing mesh data and input and output field data for the coupled analysis codes and interpolating the field values between different meshes used by the coupled codes. We found it straightforward to use MOAB to couple the PBSM basin modeling code and the FWI3D seismic code on an IBM Blue Gene/P system. We describe how the coupling was implemented and present benchmarking results for up to 8 racks of Blue Gene/P with 8192 nodes and MPI processes. The coupling code is fast compared to the analysis codes and it scales well up to at least 8192 nodes, indicating that a mesh and field database is an efficient way to implement loose multiphysics coupling for large parallel machines.

  8. Coupling a Basin Modeling and a Seismic Code using MOAB

    KAUST Repository

    Yan, Mi

    2012-06-02

    We report on a demonstration of loose multiphysics coupling between a basin modeling code and a seismic code running on a large parallel machine. Multiphysics coupling, which is one critical capability for a high performance computing (HPC) framework, was implemented using the MOAB open-source mesh and field database. MOAB provides for code coupling by storing mesh data and input and output field data for the coupled analysis codes and interpolating the field values between different meshes used by the coupled codes. We found it straightforward to use MOAB to couple the PBSM basin modeling code and the FWI3D seismic code on an IBM Blue Gene/P system. We describe how the coupling was implemented and present benchmarking results for up to 8 racks of Blue Gene/P with 8192 nodes and MPI processes. The coupling code is fast compared to the analysis codes and it scales well up to at least 8192 nodes, indicating that a mesh and field database is an efficient way to implement loose multiphysics coupling for large parallel machines.

  9. Rippability Assessment of Weathered Sedimentary Rock Mass using Seismic Refraction Methods

    Science.gov (United States)

    Ismail, M. A. M.; Kumar, N. S.; Abidin, M. H. Z.; Madun, A.

    2018-04-01

    Rippability or ease of excavation in sedimentary rocks is a significant aspect of the preliminary work of any civil engineering project. Rippability assessment was performed in this study to select an available ripping machine to rip off earth materials using the seismic velocity chart provided by Caterpillar. The research area is located at the proposed construction site for the development of a water reservoir and related infrastructure in Kampus Pauh Putra, Universiti Malaysia Perlis. The research was aimed at obtaining seismic velocity, P-wave (Vp) using a seismic refraction method to produce a 2D tomography model. A 2D seismic model was used to delineate the layers into the velocity profile. The conventional geotechnical method of using a borehole was integrated with the seismic velocity method to provide appropriate correlation. The correlated data can be used to categorize machineries for excavation activities based on the available systematic analysis procedure to predict rock rippability. The seismic velocity profile obtained was used to interpret rock layers within the ranges labelled as rippable, marginal, and non-rippable. Based on the seismic velocity method the site can be classified into loose sand stone to moderately weathered rock. Laboratory test results shows that the site’s rock material falls between low strength and high strength. Results suggest that Caterpillar’s smallest ripper, namely, D8R, can successfully excavate materials based on the test results integration from seismic velocity method and laboratory test.

  10. Seismic activity prediction using computational intelligence techniques in northern Pakistan

    Science.gov (United States)

    Asim, Khawaja M.; Awais, Muhammad; Martínez-Álvarez, F.; Iqbal, Talat

    2017-10-01

    Earthquake prediction study is carried out for the region of northern Pakistan. The prediction methodology includes interdisciplinary interaction of seismology and computational intelligence. Eight seismic parameters are computed based upon the past earthquakes. Predictive ability of these eight seismic parameters is evaluated in terms of information gain, which leads to the selection of six parameters to be used in prediction. Multiple computationally intelligent models have been developed for earthquake prediction using selected seismic parameters. These models include feed-forward neural network, recurrent neural network, random forest, multi layer perceptron, radial basis neural network, and support vector machine. The performance of every prediction model is evaluated and McNemar's statistical test is applied to observe the statistical significance of computational methodologies. Feed-forward neural network shows statistically significant predictions along with accuracy of 75% and positive predictive value of 78% in context of northern Pakistan.

  11. Radial-piston pump for drive of test machines

    Science.gov (United States)

    Nizhegorodov, A. I.; Gavrilin, A. N.; Moyzes, B. B.; Cherkasov, A. I.; Zharkevich, O. M.; Zhetessova, G. S.; Savelyeva, N. A.

    2018-01-01

    The article reviews the development of radial-piston pump with phase control and alternating-flow mode for seismic-testing platforms and other test machines. The prospects for use of the developed device are proved. It is noted that the method of frequency modulation with the detection of the natural frequencies is easily realized by using the radial-piston pump. The prospects of further research are given proof.

  12. Passive seismic investigation of Harrat Rahat

    Energy Technology Data Exchange (ETDEWEB)

    Mellors, Robert J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-04-07

    Ambient noise correlation was applied to 18 months of continuous seismic data from 14 stations. The procedure of Bensen et al [2007] was followed with some changes to optimize signal-to-noise of the results. The 18 months of correlations (representing about 1 week of CPU time on a 12 core machine) were stacked and manually inspected to yield about 40 cross-correlations. These cross-correlations represent the Green’s function between the station pairs and will be analyzed in part two of this project to yield velocity structure.

  13. Seismic studies for Fermilab future collider projects

    International Nuclear Information System (INIS)

    Lauh, J.; Shiltsev, V.

    1997-11-01

    Ground motion can cause significant beam emittance growth and orbit oscillations in large hadron colliders due to a vibration of numerous focusing magnets. Larger accelerator ring circumference leads to smaller revolution frequency and, e.g. for the Fermilab Very Large Hadron Collider(VLHC) 50-150 Hz vibrations are of particular interest as they are resonant with the beam betatron frequency. Seismic measurements at an existing large accelerator under operation can help to estimate the vibrations generated by the technical systems in future machines. Comparison of noisy and quiet microseismic conditions might be useful for proper choice of technical solutions for future colliders. This article presents results of wide-band seismic measurements at the Fermilab site, namely, in the tunnel of the Tevatron and on the surface nearby, and in two deep tunnels in the Illinois dolomite which is though to be a possible geological environment of the future accelerators

  14. Raise Boring of the ventilation shaft in Olkiluoto, 17. - 23.5.2006. Preliminary analysis of seismic signal

    Energy Technology Data Exchange (ETDEWEB)

    Saari, J.; Lakio, A. [AaF-Enprima Oy, Vantaa (Finland)

    2007-01-15

    In Olkiluoto, Posiva Oy has operated a local seismic network since February 2002. The purpose of the microearthquake measurements at Olkiluoto is to improve understanding of the structure, behaviour and long term stability of the bedrock. The studies include both tectonic and excavation-induced microearthquakes. An additional task of monitoring is related to safeguarding of the ONKALO. The possibility to excavate an illegal access to the ONKALO, have been concerned when the safeguards are discussed. Therefore all recorded explosions in the Olkiluoto area and in the ONKALO are located. If a concentration of explosions is observed, the origin of that is found out. Also a concept of hidden illegal explosions, detonated at the same time as the real excavation blasts, has been examined. According to the experience gained in Olkiluoto, it can be concluded that, as long the seismic network is in operation and the results are analysed by a skilled person, it is practically impossible to do illegal excavation by blasts. In this report a possibility of seismic monitoring of illegal excavation done by tunnel boring machine has been investigated. Characteristics of the seismic signal generated by the raise boring machine are analysed. According to this study, it can be concluded that the generated seismic signal can be detected and the source of the signal can be located. However, this task calls for different kind of monitoring system than that, which is currently used for monitoring microearthquakes and explosions. (orig.)

  15. Raise Boring of the ventilation shaft in Olkiluoto, 17. - 23.5.2006. Preliminary analysis of seismic signal

    International Nuclear Information System (INIS)

    Saari, J.; Lakio, A.

    2007-01-01

    In Olkiluoto, Posiva Oy has operated a local seismic network since February 2002. The purpose of the microearthquake measurements at Olkiluoto is to improve understanding of the structure, behaviour and long term stability of the bedrock. The studies include both tectonic and excavation-induced microearthquakes. An additional task of monitoring is related to safeguarding of the ONKALO. The possibility to excavate an illegal access to the ONKALO, have been concerned when the safeguards are discussed. Therefore all recorded explosions in the Olkiluoto area and in the ONKALO are located. If a concentration of explosions is observed, the origin of that is found out. Also a concept of hidden illegal explosions, detonated at the same time as the real excavation blasts, has been examined. According to the experience gained in Olkiluoto, it can be concluded that, as long the seismic network is in operation and the results are analysed by a skilled person, it is practically impossible to do illegal excavation by blasts. In this report a possibility of seismic monitoring of illegal excavation done by tunnel boring machine has been investigated. Characteristics of the seismic signal generated by the raise boring machine are analysed. According to this study, it can be concluded that the generated seismic signal can be detected and the source of the signal can be located. However, this task calls for different kind of monitoring system than that, which is currently used for monitoring microearthquakes and explosions. (orig.)

  16. Seismic-load-induced human errors and countermeasures using computer graphics in plant-operator communication

    International Nuclear Information System (INIS)

    Hara, Fumio

    1988-01-01

    This paper remarks the importance of seismic load-induced human errors in plant operation by delineating the characteristics of the task performance of human beings under seismic loads. It focuses on man-machine communication via multidimensional data like that conventionally displayed on large panels in a plant control room. It demonstrates a countermeasure to human errors using a computer graphics technique that conveys the global state of the plant operation to operators through cartoon-like, colored graphs in the form of faces that, with different facial expressions, show the plant safety status. (orig.)

  17. Design and Construction of Operation Bridge for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Choi, Jinbok; Lee, Jongmin; Oh, Jinho

    2015-01-01

    The operation bridge contains a lower working deck mounted on a saddle that travels on rails. Upright members are mounted on the saddle to support the upper structure and two hoist monorails. The saddle contains an anti-derail system that is composed of seismic lugs and guide rollers. The operation bridge travels along the rails to transport the fuel assembly, irradiated object, and reactor components in the pools by using tools. Hoists are installed at the top girder. The hoist is suspended from the monorail by means of a motor driven trolley that runs along the monorail. Movements of hoist and trolley are controlled by using the control pendant switch. Processes of design and construction of the operation bridge for the research reactor are introduced. The operation bridge is designed under consideration of functions of handling equipment in the pool and operational limits for safety. Structural analysis is carried out to evaluate the structural integrity in the seismic events. Tests and inspections are also performed during fabrication and installation to confirm the function and safety of the operation bridge

  18. A study of the feasibility of monitoring sealed geological repositories using seismic sensors

    International Nuclear Information System (INIS)

    Garbin, H.D.; Herrington, P.B.; Kromer, R.P.

    1999-01-01

    Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals). The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository's southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM. (author)

  19. A study of the feasibility of monitoring sealed geological repositories using seismic sensors

    International Nuclear Information System (INIS)

    Garbin, H.D.; Herrington, P.B.; Kromer, R.P.

    1997-10-01

    Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals.) The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository's southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM

  20. Automatic classification of endogenous seismic sources within a landslide body using random forest algorithm

    Science.gov (United States)

    Provost, Floriane; Hibert, Clément; Malet, Jean-Philippe; Stumpf, André; Doubre, Cécile

    2016-04-01

    Different studies have shown the presence of microseismic activity in soft-rock landslides. The seismic signals exhibit significantly different features in the time and frequency domains which allow their classification and interpretation. Most of the classes could be associated with different mechanisms of deformation occurring within and at the surface (e.g. rockfall, slide-quake, fissure opening, fluid circulation). However, some signals remain not fully understood and some classes contain few examples that prevent any interpretation. To move toward a more complete interpretation of the links between the dynamics of soft-rock landslides and the physical processes controlling their behaviour, a complete catalog of the endogeneous seismicity is needed. We propose a multi-class detection method based on the random forests algorithm to automatically classify the source of seismic signals. Random forests is a supervised machine learning technique that is based on the computation of a large number of decision trees. The multiple decision trees are constructed from training sets including each of the target classes. In the case of seismic signals, these attributes may encompass spectral features but also waveform characteristics, multi-stations observations and other relevant information. The Random Forest classifier is used because it provides state-of-the-art performance when compared with other machine learning techniques (e.g. SVM, Neural Networks) and requires no fine tuning. Furthermore it is relatively fast, robust, easy to parallelize, and inherently suitable for multi-class problems. In this work, we present the first results of the classification method applied to the seismicity recorded at the Super-Sauze landslide between 2013 and 2015. We selected a dozen of seismic signal features that characterize precisely its spectral content (e.g. central frequency, spectrum width, energy in several frequency bands, spectrogram shape, spectrum local and global maxima

  1. Rail assembly for use in a radioactive environment

    International Nuclear Information System (INIS)

    Watts, R.E.

    1989-01-01

    An improved rail assembly and method of construction thereof is disclosed herein that is particularly adapted for use with a crane trolley in a hot cell environment which is exposed to airborne and liquidborne radioactive contaminants. The rail assembly is generally comprised of a support wall having an elongated, rail-housing recess having a floor, side wall and ceiling. The floor of the recess is defined at least in party by the load-bearing surface of a rail, and is substantially flat, level and crevice-free to facilitate the drainage of liquids out of the recess. The ceiling of the recess overhangs and thereby captures trolley wheels within the recess to prevent them from becoming dislodged from the recess during a seismic disturbance. Finally, the interior of the recess includes a power track having a slot for receiving a sliding electrical connector from the crane trolley. The power track is mounted in an upper corner of the recess with its connector-receiving groove oriented downwardly to facilitate the drainage of liquidborne contaminants and to discourage the collection of airborne contaminants within the track

  2. Seismic isolation - efficient procedure for seismic response assessement

    International Nuclear Information System (INIS)

    Zamfir, M. A.; Androne, M.

    2016-01-01

    The aim of this analysis is to reduce the dynamic response of a structure. The seismic isolation solution must take into consideration the specific site ground motion. In this paper will be presented results obtained by applying the seismic isolation method. Based on the obtained results, important conclusions can be outlined: the seismic isolation device has the ability to reduce seismic acceleration of the seismic isolated structure to values that no longer present a danger to people and environment; the seismic isolation solution is limiting devices deformations to safety values for ensuring structural integrity and stability of the entire system; the effective seismic energy dissipation and with no side effects both for the seismic isolated building and for the devices used, and the return to the initial position before earthquake occurence are obtained with acceptable permanent displacement. (authors)

  3. Seismic testing

    International Nuclear Information System (INIS)

    Sollogoub, Pierre

    2001-01-01

    This lecture deals with: qualification methods for seismic testing; objectives of seismic testing; seismic testing standards including examples; main content of standard; testing means; and some important elements of seismic testing

  4. IAEA specialists' meeting on seismic isolation technology. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-07-01

    The objective of the Meeting on Seismic Isolation Technology was to provide a forum for review and discussion of seismic isolation technology applicable to thermal and fast reactors. The meeting was conducted consistent with the recommendations of the IAEA Working Group Meeting on Fast Breeder Reactor-Block Antiseismic Design and Verification in October 1987, to augment a coordinated research program with specific recommendations and an assessment of technology in the area of seismic isolation. Seismic isolation has become an attractive means for mitigating the consequences of severe earthquakes. Although the general idea of seismic isolation has been considered since the turn of the century, real practical applications have evolved, at an accelerating pace, over the last fifteen years aided by several key developments: (1) recent advances in hardware developments in the form of reliable elastomer bearings, (2) development of reliable analytical methods for the prediction of dynamic responses of structures (3) construction of large bearing test machines and large shake tables to simulate earthquake effects on structures for validation analytical models and demonstration of performance characteristics, and (4) advances in seismological engineering. Although the applications and developments of seismic isolation technology have mainly benefited commercial facilities and structures, including office buildings, research laboratories, hospitals, museums, bridges, ship loaders, etc., several seismically isolated nuclear facilities were implemented: the four 900 MWe pressurized water reactor units of the Cruas plant in France, the two Framatome units in Koeberg, South Africa, a nuclear waste storage facility in France and a nuclear fuel reprocessing plant in England. The scope of this specialists' meeting was to review the state-of-the-art technology related to the performance of seismic isolator elements and systems, performance limits and margins, criteria for the

  5. IAEA specialists' meeting on seismic isolation technology. Proceedings

    International Nuclear Information System (INIS)

    1992-01-01

    The objective of the Meeting on Seismic Isolation Technology was to provide a forum for review and discussion of seismic isolation technology applicable to thermal and fast reactors. The meeting was conducted consistent with the recommendations of the IAEA Working Group Meeting on Fast Breeder Reactor-Block Antiseismic Design and Verification in October 1987, to augment a coordinated research program with specific recommendations and an assessment of technology in the area of seismic isolation. Seismic isolation has become an attractive means for mitigating the consequences of severe earthquakes. Although the general idea of seismic isolation has been considered since the turn of the century, real practical applications have evolved, at an accelerating pace, over the last fifteen years aided by several key developments: (1) recent advances in hardware developments in the form of reliable elastomer bearings, (2) development of reliable analytical methods for the prediction of dynamic responses of structures (3) construction of large bearing test machines and large shake tables to simulate earthquake effects on structures for validation analytical models and demonstration of performance characteristics, and (4) advances in seismological engineering. Although the applications and developments of seismic isolation technology have mainly benefited commercial facilities and structures, including office buildings, research laboratories, hospitals, museums, bridges, ship loaders, etc., several seismically isolated nuclear facilities were implemented: the four 900 MWe pressurized water reactor units of the Cruas plant in France, the two Framatome units in Koeberg, South Africa, a nuclear waste storage facility in France and a nuclear fuel reprocessing plant in England. The scope of this specialists' meeting was to review the state-of-the-art technology related to the performance of seismic isolator elements and systems, performance limits and margins, criteria for the

  6. Automated seismic detection of landslides at regional scales: a Random Forest based detection algorithm

    Science.gov (United States)

    Hibert, C.; Michéa, D.; Provost, F.; Malet, J. P.; Geertsema, M.

    2017-12-01

    Detection of landslide occurrences and measurement of their dynamics properties during run-out is a high research priority but a logistical and technical challenge. Seismology has started to help in several important ways. Taking advantage of the densification of global, regional and local networks of broadband seismic stations, recent advances now permit the seismic detection and location of landslides in near-real-time. This seismic detection could potentially greatly increase the spatio-temporal resolution at which we study landslides triggering, which is critical to better understand the influence of external forcings such as rainfalls and earthquakes. However, detecting automatically seismic signals generated by landslides still represents a challenge, especially for events with small mass. The low signal-to-noise ratio classically observed for landslide-generated seismic signals and the difficulty to discriminate these signals from those generated by regional earthquakes or anthropogenic and natural noises are some of the obstacles that have to be circumvented. We present a new method for automatically constructing instrumental landslide catalogues from continuous seismic data. We developed a robust and versatile solution, which can be implemented in any context where a seismic detection of landslides or other mass movements is relevant. The method is based on a spectral detection of the seismic signals and the identification of the sources with a Random Forest machine learning algorithm. The spectral detection allows detecting signals with low signal-to-noise ratio, while the Random Forest algorithm achieve a high rate of positive identification of the seismic signals generated by landslides and other seismic sources. The processing chain is implemented to work in a High Performance Computers centre which permits to explore years of continuous seismic data rapidly. We present here the preliminary results of the application of this processing chain for years

  7. Multi-hole seismic modeling in 3-D space and cross-hole seismic tomography analysis for boulder detection

    Science.gov (United States)

    Cheng, Fei; Liu, Jiangping; Wang, Jing; Zong, Yuquan; Yu, Mingyu

    2016-11-01

    A boulder stone, a common geological feature in south China, is referred to the remnant of a granite body which has been unevenly weathered. Undetected boulders could adversely impact the schedule and safety of subway construction when using tunnel boring machine (TBM) method. Therefore, boulder detection has always been a key issue demanded to be solved before the construction. Nowadays, cross-hole seismic tomography is a high resolution technique capable of boulder detection, however, the method can only solve for velocity in a 2-D slice between two wells, and the size and central position of the boulder are generally difficult to be accurately obtained. In this paper, the authors conduct a multi-hole wave field simulation and characteristic analysis of a boulder model based on the 3-D elastic wave staggered-grid finite difference theory, and also a 2-D imaging analysis based on first arrival travel time. The results indicate that (1) full wave field records could be obtained from multi-hole seismic wave simulations. Simulation results describe that the seismic wave propagation pattern in cross-hole high-velocity spherical geological bodies is more detailed and can serve as a basis for the wave field analysis. (2) When a cross-hole seismic section cuts through the boulder, the proposed method provides satisfactory cross-hole tomography results; however, when the section is closely positioned to the boulder, such high-velocity object in the 3-D space would impact on the surrounding wave field. The received diffracted wave interferes with the primary wave and in consequence the picked first arrival travel time is not derived from the profile, which results in a false appearance of high-velocity geology features. Finally, the results of 2-D analysis in 3-D modeling space are comparatively analyzed with the physical model test vis-a-vis the effect of high velocity body on the seismic tomographic measurements.

  8. seismic-py: Reading seismic data with Python

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available The field of seismic exploration of the Earth has changed
    dramatically over the last half a century. The Society of Exploration
    Geophysicists (SEG has worked to create standards to store the vast
    amounts of seismic data in a way that will be portable across computer
    architectures. However, it has been impossible to predict the needs of the
    immense range of seismic data acquisition systems. As a result, vendors have
    had to bend the rules to accommodate the needs of new instruments and
    experiment types. For low level access to seismic data, there is need for a
    standard open source library to allow access to a wide range of vendor data
    files that can handle all of the variations. A new seismic software package,
    seismic-py, provides an infrastructure for creating and managing drivers for
    each particular format. Drivers can be derived from one of the known formats
    and altered to handle any slight variations. Alternatively drivers can be
    developed from scratch for formats that are very different from any previously
    defined format. Python has been the key to making driver development easy
    and efficient to implement. The goal of seismic-py is to be the base system
    that will power a wide range of experimentation with seismic data and at the
    same time provide clear documentation for the historical record of seismic
    data formats.

  9. Design of turbine foundations in seismic zones. Earthquake protection strategies; Planung von Turbinenfundamenten in Erdbebengebieten. Strategien zum Erdbebenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Ashish Kumar [GERB Vibration Control Systems, Noida (India); Nawrotzki, Peter [GERB Schwingungsisolierungen GmbH und Co. KG, Berlin (Germany); Siepe, Daniel [GERB Engineering GmbH, Essen (Germany)

    2011-04-15

    This contribution reveals basic principles of elastic support systems and applications on power plant equipment and buildings in medium and high seismic areas. Spring-damper combinations with special stiffness properties are used to reduce seismic acceleration levels of turbine components and other safety or non-safety related structures. For turbine buildings, the integration of the turbine substructure into the machine building can additionally reduce the relative displacement between both the structures as well as the stress levels in all structural members. (orig.)

  10. Development of group setup strategies for makespan minimization in PCB assembly

    DEFF Research Database (Denmark)

    Yilmaz, I.O.; Grunow, M.; Günther, H.-O.

    2007-01-01

    of the component magazine into account. We demonstrate the effectiveness of our approach in an extensive numerical investigation of a single-gantry collect-and-place machine equipped with a rotary placement head and an interchangeable feeder trolley. Compared to conventional methodologies, the proposed group setup...

  11. Seismic monitoring experiment of raise boring in 2014

    International Nuclear Information System (INIS)

    Saari, J.; Malm, M.

    2015-01-01

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

  12. Seismic monitoring experiment of raise boring in 2014

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-01-15

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

  13. Study on structural seismic margin and probabilistic seismic risk. Development of a structural capacity-seismic risk diagram

    International Nuclear Information System (INIS)

    Nakajima, Masato; Ohtori, Yasuki; Hirata, Kazuta

    2010-01-01

    Seismic margin is extremely important index and information when we evaluate and account seismic safety of critical structures, systems and components quantitatively. Therefore, it is required that electric power companies evaluate the seismic margin of each plant in back-check of nuclear power plants in Japan. The seismic margin of structures is usually defined as a structural capacity margin corresponding to design earthquake ground motion. However, there is little agreement as to the definition of the seismic margin and we have no knowledge about a relationship between the seismic margin and seismic risk (annual failure probability) which is obtained in PSA (Probabilistic Safety Assessment). The purpose of this report is to discuss a definition of structural seismic margin and to develop a diagram which can identify a relation between seismic margin and seismic risk. The main results of this paper are described as follows: (1) We develop seismic margin which is defined based on the fact that intensity of earthquake ground motion is more appropriate than the conventional definition (i.e., the response-based seismic margin) for the following reasons: -seismic margin based on earthquake ground motion is invariant where different typed structures are considered, -stakeholders can understand the seismic margin based on the earthquake ground motion better than the response-based one. (2) The developed seismic margin-risk diagram facilitates us to judge easily whether we need to perform detailed probabilistic risk analysis or only deterministic analysis, given that the reference risk level although information on the uncertainty parameter beta is not obtained. (3) We have performed numerical simulations based on the developed method for four sites in Japan. The structural capacity-risk diagram differs depending on each location because the diagram is greatly influenced by seismic hazard information for a target site. Furthermore, the required structural capacity

  14. Seismic Ecology

    Science.gov (United States)

    Seleznev, V. S.; Soloviev, V. M.; Emanov, A. F.

    The paper is devoted to researches of influence of seismic actions for industrial and civil buildings and people. The seismic actions bring influence directly on the people (vibration actions, force shocks at earthquakes) or indirectly through various build- ings and the constructions and can be strong (be felt by people) and weak (be fixed by sensing devices). The great number of work is devoted to influence of violent seismic actions (first of all of earthquakes) on people and various constructions. This work is devoted to study weak, but long seismic actions on various buildings and people. There is a need to take into account seismic oscillations, acting on the territory, at construction of various buildings on urbanized territories. Essential influence, except for violent earthquakes, man-caused seismic actions: the explosions, seismic noise, emitted by plant facilities and moving transport, radiation from high-rise buildings and constructions under action of a wind, etc. can exert. Materials on increase of man- caused seismicity in a number of regions in Russia, which earlier were not seismic, are presented in the paper. Along with maps of seismic microzoning maps to be built indicating a variation of amplitude spectra of seismic noise within day, months, years. The presence of an information about amplitudes and frequencies of oscillations from possible earthquakes and man-caused oscillations in concrete regions allows carry- ing out soundly designing and construction of industrial and civil housing projects. The construction of buildings even in not seismically dangerous regions, which have one from resonance frequencies coincident on magnitude to frequency of oscillations, emitted in this place by man-caused objects, can end in failure of these buildings and heaviest consequences for the people. The practical examples of detail of engineering- seismological investigation of large industrial and civil housing projects of Siberia territory (hydro power

  15. Distributed state machine supervision for long-baseline gravitational-wave detectors

    International Nuclear Information System (INIS)

    Rollins, Jameson Graef

    2016-01-01

    The Laser Interferometer Gravitational-wave Observatory (LIGO) consists of two identical yet independent, widely separated, long-baseline gravitational-wave detectors. Each Advanced LIGO detector consists of complex optical-mechanical systems isolated from the ground by multiple layers of active seismic isolation, all controlled by hundreds of fast, digital, feedback control systems. This article describes a novel state machine-based automation platform developed to handle the automation and supervisory control challenges of these detectors. The platform, called Guardian, consists of distributed, independent, state machine automaton nodes organized hierarchically for full detector control. User code is written in standard Python and the platform is designed to facilitate the fast-paced development process associated with commissioning the complicated Advanced LIGO instruments. While developed specifically for the Advanced LIGO detectors, Guardian is a generic state machine automation platform that is useful for experimental control at all levels, from simple table-top setups to large-scale multi-million dollar facilities.

  16. Distributed state machine supervision for long-baseline gravitational-wave detectors

    Energy Technology Data Exchange (ETDEWEB)

    Rollins, Jameson Graef, E-mail: jameson.rollins@ligo.org [LIGO Laboratory, California Institute of Technology, Pasadena, California 91125 (United States)

    2016-09-15

    The Laser Interferometer Gravitational-wave Observatory (LIGO) consists of two identical yet independent, widely separated, long-baseline gravitational-wave detectors. Each Advanced LIGO detector consists of complex optical-mechanical systems isolated from the ground by multiple layers of active seismic isolation, all controlled by hundreds of fast, digital, feedback control systems. This article describes a novel state machine-based automation platform developed to handle the automation and supervisory control challenges of these detectors. The platform, called Guardian, consists of distributed, independent, state machine automaton nodes organized hierarchically for full detector control. User code is written in standard Python and the platform is designed to facilitate the fast-paced development process associated with commissioning the complicated Advanced LIGO instruments. While developed specifically for the Advanced LIGO detectors, Guardian is a generic state machine automation platform that is useful for experimental control at all levels, from simple table-top setups to large-scale multi-million dollar facilities.

  17. A new seismic station in Romania the Bucovina seismic array

    International Nuclear Information System (INIS)

    Grigore, Adrian; Grecu, Bogdan; Ionescu, Constantin; Ghica, Daniela; Popa, Mihaela; Rizescu, Mihaela

    2002-01-01

    Recently, a new seismic monitoring station, the Bucovina Seismic Array, has been established in the northern part of Romania, in a joint effort of the Air Force Technical Applications Center, USA, and the National Institute for Earth Physics, Romania. The array consists of 10 seismic sensors (9 short-period and one broad band) located in boreholes and distributed in a 5 x 5 km area. On July 24, 2002 the official Opening Ceremony of Bucovina Seismic Array took place in the area near the city of Campulung Moldovenesc in the presence of Romanian Prime Minister, Adrian Nastase. Starting with this date, the new seismic monitoring system became fully operational by continuous recording and transmitting data in real-time to the National Data Center of Romania, in Bucharest and to the National Data Center of USA, in Florida. Bucovina Seismic Array, added to the present Seismic Network, will provide much better seismic monitoring coverage of Romania's territory, on-scale recording for weak-to-strong events, and will contribute to advanced seismological studies on seismic hazard and risk, local effects and microzonation, seismic source physics, Earth structure. (authors)

  18. The Seismic Analyzer: Interpreting and Illustrating 2D Seismic Data

    OpenAIRE

    Patel, Daniel; Giertsen, Christopher; Thurmond, John; Gjelberg, John; Gröller, Eduard

    2008-01-01

    We present a toolbox for quickly interpreting and illustrating 2D slices of seismic volumetric reflection data. Searching for oil and gas involves creating a structural overview of seismic reflection data to identify hydrocarbon reservoirs. We improve the search of seismic structures by precalculating the horizon structures of the seismic data prior to interpretation. We improve the annotation of seismic structures by applying novel illustrative rendering algorithms tailored to seism...

  19. Intelligent inversion method for pre-stack seismic big data based on MapReduce

    Science.gov (United States)

    Yan, Xuesong; Zhu, Zhixin; Wu, Qinghua

    2018-01-01

    Seismic exploration is a method of oil exploration that uses seismic information; that is, according to the inversion of seismic information, the useful information of the reservoir parameters can be obtained to carry out exploration effectively. Pre-stack data are characterised by a large amount of data, abundant information, and so on, and according to its inversion, the abundant information of the reservoir parameters can be obtained. Owing to the large amount of pre-stack seismic data, existing single-machine environments have not been able to meet the computational needs of the huge amount of data; thus, the development of a method with a high efficiency and the speed to solve the inversion problem of pre-stack seismic data is urgently needed. The optimisation of the elastic parameters by using a genetic algorithm easily falls into a local optimum, which results in a non-obvious inversion effect, especially for the optimisation effect of the density. Therefore, an intelligent optimisation algorithm is proposed in this paper and used for the elastic parameter inversion of pre-stack seismic data. This algorithm improves the population initialisation strategy by using the Gardner formula and the genetic operation of the algorithm, and the improved algorithm obtains better inversion results when carrying out a model test with logging data. All of the elastic parameters obtained by inversion and the logging curve of theoretical model are fitted well, which effectively improves the inversion precision of the density. This algorithm was implemented with a MapReduce model to solve the seismic big data inversion problem. The experimental results show that the parallel model can effectively reduce the running time of the algorithm.

  20. Seismic Microzonation for Refinement of Seismic Load Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Savich, A. I.; Bugaevskii, A. G., E-mail: office@geodyn.ru, E-mail: bugaevskiy@geodyn.ru [Center of the Office of Geodynamic Observations in the Power Sector, an affiliate of JSC “Institut Gidroproekt” (Russian Federation)

    2016-05-15

    Functional dependencies are established for the characteristics of seismic transients recorded at various points of a studied site, which are used to propose a new approach to seismic microzonation (SMZ) that enables the creation of new SMZ maps of strong seismic motion, with due regard for dynamic parameters of recorded transients during weak earthquakes.

  1. The seismic analyzer: interpreting and illustrating 2D seismic data.

    Science.gov (United States)

    Patel, Daniel; Giertsen, Christopher; Thurmond, John; Gjelberg, John; Gröller, M Eduard

    2008-01-01

    We present a toolbox for quickly interpreting and illustrating 2D slices of seismic volumetric reflection data. Searching for oil and gas involves creating a structural overview of seismic reflection data to identify hydrocarbon reservoirs. We improve the search of seismic structures by precalculating the horizon structures of the seismic data prior to interpretation. We improve the annotation of seismic structures by applying novel illustrative rendering algorithms tailored to seismic data, such as deformed texturing and line and texture transfer functions. The illustrative rendering results in multi-attribute and scale invariant visualizations where features are represented clearly in both highly zoomed in and zoomed out views. Thumbnail views in combination with interactive appearance control allows for a quick overview of the data before detailed interpretation takes place. These techniques help reduce the work of seismic illustrators and interpreters.

  2. Seismicity and seismic monitoring in the Asse salt mine

    International Nuclear Information System (INIS)

    Flach, D.; Gommlich, G.; Hente, B.

    1987-01-01

    Seismicity analyses are made in order to assess the safety of candidate sites for ultimate disposal of hazardous wastes. The report in hand reviews the seismicity history of the Asse salt mine and presents recent results of a measuring campaign made in the area. The monitoring network installed at the site supplies data and information on the regional seismicity, on seismic amplitudes under ground and above ground, and on microseismic activities. (DG) [de

  3. The operation and maintenance of the SLAR system at Bruce A

    Energy Technology Data Exchange (ETDEWEB)

    Ahuja, S [Ontario Hydro, Tiverton, ON (Canada). Bruce Nuclear Generating Station-A

    1997-12-31

    The SLAR (Spacer Location And Repositioning) system at Bruce A consists of two (2) Delivery Machines and a Fuelling Machine Trolley equipped with the D{sub 2}0 and Air auxiliary systems. The Delivery Machines are designed to perform all the Fuelling Machine operations and have the capability to rapidly defuel/refuel a reactor channel and traverse the SLAR tool to locate and reposition the spacers in the channel. The number of functions that a Delivery Machine must perform makes it more complex as compared to the operations of a Fuelling Machine. The paper discusses the operation of the SLAR Delivery Machines and the problems encountered with the operation and maintenance of this system at Bruce A. (author). 8 figs.

  4. German seismic regulations

    International Nuclear Information System (INIS)

    Danisch, Ruediger

    2002-01-01

    Rules and regulations for seismic design in Germany cover the following: seismic design of conventional buildings; and seismic design of nuclear facilities. Safety criteria for NPPs, accident guidelines, and guidelines for PWRs as well as safety standards are cited. Safety standards concerned with NPPs seismic design include basic principles, soil analysis, design of building structures, design of mechanical and electrical components, seismic instrumentation, and measures to be undertaken after the earthquake

  5. Establishing seismic design criteria to achieve an acceptable seismic margin

    International Nuclear Information System (INIS)

    Kennedy, R.P.

    1997-01-01

    In order to develop a risk based seismic design criteria the following four issues must be addressed: (1) What target annual probability of seismic induced unacceptable performance is acceptable? (2). What minimum seismic margin is acceptable? (3) Given the decisions made under Issues 1 and 2, at what annual frequency of exceedance should the Safe Shutdown Earthquake ground motion be defined? (4) What seismic design criteria should be established to reasonably achieve the seismic margin defined under Issue 2? The first issue is purely a policy decision and is not addressed in this paper. Each of the other three issues are addressed. Issues 2 and 3 are integrally tied together so that a very large number of possible combinations of responses to these two issues can be used to achieve the target goal defined under Issue 1. Section 2 lays out a combined approach to these two issues and presents three potentially attractive combined resolutions of these two issues which reasonably achieves the target goal. The remainder of the paper discusses an approach which can be used to develop seismic design criteria aimed at achieving the desired seismic margin defined in resolution of Issue 2. Suggestions for revising existing seismic design criteria to more consistently achieve the desired seismic margin are presented

  6. Seismic capacity of a reinforced concrete frame structure without seismic detailing and limited ductility seismic design in moderate seismicity

    International Nuclear Information System (INIS)

    Kim, J. K.; Kim, I. H.

    1999-01-01

    A four-story reinforced concrete frame building model is designed for the gravity loads only. Static nonlinear pushover analyses are performed in two orthogonal horizontal directions. The overall capacity curves are converted into ADRS spectra and compared with demand spectra. At several points the deformed shape, moment and shear distribution are calculated. Based on these results limited ductility seismic design concept is proposed as an alternative seismic design approach in moderate seismicity resign

  7. Burar seismic station: evaluation of seismic performance

    International Nuclear Information System (INIS)

    Ghica, Daniela; Popa, Mihaela

    2005-01-01

    A new seismic monitoring system, the Bucovina Seismic Array (BURAR), has been established since July 2002, in the Northern part of Romania, in a joint effort of the Air Force Technical Applications Center, USA, and the National Institute for Earth Physics (NIEP), Romania. The small-aperture array consists of 10 seismic sensors (9 vertical short-period and one three-component broad band) located in boreholes and distributed in a 5 x 5 km 2 area. At present, the seismic data are continuously recorded by the BURAR and transmitted in real-time to the Romanian National Data Center in Bucharest and National Data Center of the USA, in Florida. Based on the BURAR seismic information gathered at the National Data Center, NIEP (ROM N DC), in the August 2002 - December 2004 time interval, analysis and statistical assessments were performed. Following the preliminary processing of the data, several observations on the global performance of the BURAR system were emphasized. Data investigation showed an excellent efficiency of the BURAR system particularly in detecting teleseismic and regional events. Also, a statistical analysis for the BURAR detection capability of the local Vrancea events was performed in terms of depth and magnitude for the year 2004. The high signal detection capability of the BURAR resulted, generally, in improving the location solutions for the Vrancea seismic events. The location solution accuracy is enhanced when adding BURAR recordings, especially in the case of low magnitude events (recorded by few stations). The location accuracy is increased, both in terms of constraining hypocenter depth and epicentral coordinates. Our analysis certifies the importance of the BURAR system in NIEP efforts to elaborate seismic bulletins. Furthermore, the specific procedures for array data processing (beam forming, f-k analysis) increase significantly the signal-to-noise ratio by summing up the coherent signals from the array components, and ensure a better accuracy

  8. Seismic waveform modeling over cloud

    Science.gov (United States)

    Luo, Cong; Friederich, Wolfgang

    2016-04-01

    With the fast growing computational technologies, numerical simulation of seismic wave propagation achieved huge successes. Obtaining the synthetic waveforms through numerical simulation receives an increasing amount of attention from seismologists. However, computational seismology is a data-intensive research field, and the numerical packages usually come with a steep learning curve. Users are expected to master considerable amount of computer knowledge and data processing skills. Training users to use the numerical packages, correctly access and utilize the computational resources is a troubled task. In addition to that, accessing to HPC is also a common difficulty for many users. To solve these problems, a cloud based solution dedicated on shallow seismic waveform modeling has been developed with the state-of-the-art web technologies. It is a web platform integrating both software and hardware with multilayer architecture: a well designed SQL database serves as the data layer, HPC and dedicated pipeline for it is the business layer. Through this platform, users will no longer need to compile and manipulate various packages on the local machine within local network to perform a simulation. By providing users professional access to the computational code through its interfaces and delivering our computational resources to the users over cloud, users can customize the simulation at expert-level, submit and run the job through it.

  9. Seismic hazard estimation based on the distributed seismicity in northern China

    Science.gov (United States)

    Yang, Yong; Shi, Bao-Ping; Sun, Liang

    2008-03-01

    In this paper, we have proposed an alternative seismic hazard modeling by using distributed seismicites. The distributed seismicity model does not need delineation of seismic source zones, and simplify the methodology of probabilistic seismic hazard analysis. Based on the devastating earthquake catalogue, we established three seismicity model, derived the distribution of a-value in northern China by using Gaussian smoothing function, and calculated peak ground acceleration distributions for this area with 2%, 5% and 10% probability of exceedance in a 50-year period by using three attenuation models, respectively. In general, the peak ground motion distribution patterns are consistent with current seismic hazard map of China, but in some specific seismic zones which include Shanxi Province and Shijiazhuang areas, our results indicated a little bit higher peak ground motions and zonation characters which are in agreement with seismicity distribution patterns in these areas. The hazard curves have been developed for Beijing, Tianjin, Taiyuan, Tangshan, and Ji’nan, the metropolitan cities in the northern China. The results showed that Tangshan, Taiyuan, Beijing has a higher seismic hazard than that of other cities mentioned above.

  10. Optimization of the seismic pit of the Tokamak building of ITER

    International Nuclear Information System (INIS)

    Beltran, F.; Combescure, D.; Hanna, G.; Ezeberry, J.

    2010-01-01

    The Tokamak Complex of ITER is the structure housing the Tokamak machine, the Tritium building and the Diagnostic building. This structure, with a plan of about 120 x 80 m, will be built with a base isolation system formed with over 500 steel reinforced neoprene pads. The pads will be mounted on top of short columns or plinths, supported by a bottom basemat resting directly on rock. Foundation level is about 20 m below grade level. Consequently, a ground supporting system, such as retaining walls, is required to protect the structure. The walls, together with the basemat, form the seismic pit of the Tokamak Complex. After the initial design of the seismic pit walls and basemat was closed, a new report on the water table levels to be expected for different return periods was issued. The report introduced a substantial reduction of ground water levels with respect to the previous design basis. Following this reduction, a new design for the seismic pit walls and basemat was developed. The goal was to introduce the new optimized design as an alternative in the Call for Tenders related to the construction of the seismic pit. The design of the seismic pit is governed by the seismic action, even though the whole pit is embedded in a limestone rock of medium to good quality. For optimizing the design, a review of geotechnical parameters has been carried out first, using the huge body of information generated after more than 20 years of site investigation. Afterwards, seismic thrusts on the walls have been computed using different procedures, from conventional rock wedged equilibrium analyses to more sophisticated techniques based on the interaction of discrete blocks configuring the rock massif. In addition, internal forces and moments have been determined at the basemat from the ground deformation parameters, using finite element models. Finally, steel reinforcement has been obtained for the several sections of the retaining walls and the basemat, complying with the

  11. Calculation of seismic response of a flexible rotor by complex modal method, 1

    International Nuclear Information System (INIS)

    Azuma, Takao; Saito, Shinobu

    1984-01-01

    In rotary machines, at the time of earthquakes, whether the rotating part and stationary part touch or whether the bearings and seals are damaged or not are problems. In order to examine these problems, it is necessary to analyze the seismic response of a rotary shaft or sometimes a casing system. But the conventional analysis methods are unsatisfactory. Accordingly, in the case of a general shaft system supported with slide bearings and on which gyro effect acts, complex modal method must be used. This calculation method is explained in detail in the book of Lancaster, however, when this method is applied to the seismic response of rotary shafts, the calculation time is considerably different according to the method of final integration. In this study, good results were obtained when the method which did not depend on numerical integration was attempted. The equation of motion and its solution, the displacement vector of a foundation, the verification of the calculation program and the example of calculating the seismic response of two coupled rotor shafts are reported. (Kako, I.)

  12. Progressive Seismic Failure, Seismic Gap, and Great Seismic Risk across the Densely Populated North China Basin

    Science.gov (United States)

    Yin, A.; Yu, X.; Shen, Z.

    2014-12-01

    Although the seismically active North China basin has the most complete written records of pre-instrumentation earthquakes in the world, this information has not been fully utilized for assessing potential earthquake hazards of this densely populated region that hosts ~200 million people. In this study, we use the historical records to document the earthquake migration pattern and the existence of a 180-km seismic gap along the 600-km long right-slip Tangshan-Hejian-Cixian (THC) fault zone that cuts across the North China basin. The newly recognized seismic gap, which is centered at Tianjin with a population of 11 million people and ~120 km from Beijing (22 million people) and Tangshan (7 million people), has not been ruptured in the past 1000 years by M≥6 earthquakes. The seismic migration pattern in the past millennium suggests that the epicenters of major earthquakes have shifted towards this seismic gap along the THC fault, which implies that the 180- km gap could be the site of the next great earthquake with M≈7.6 if it is ruptured by a single event. Alternatively, the seismic gap may be explained by aseismic creeping or seismic strain transfer between active faults.

  13. Time-Independent Annual Seismic Rates, Based on Faults and Smoothed Seismicity, Computed for Seismic Hazard Assessment in Italy

    Science.gov (United States)

    Murru, M.; Falcone, G.; Taroni, M.; Console, R.

    2017-12-01

    In 2015 the Italian Department of Civil Protection, started a project for upgrading the official Italian seismic hazard map (MPS04) inviting the Italian scientific community to participate in a joint effort for its realization. We participated providing spatially variable time-independent (Poisson) long-term annual occurrence rates of seismic events on the entire Italian territory, considering cells of 0.1°x0.1° from M4.5 up to M8.1 for magnitude bin of 0.1 units. Our final model was composed by two different models, merged in one ensemble model, each one with the same weight: the first one was realized by a smoothed seismicity approach, the second one using the seismogenic faults. The spatial smoothed seismicity was obtained using the smoothing method introduced by Frankel (1995) applied to the historical and instrumental seismicity. In this approach we adopted a tapered Gutenberg-Richter relation with a b-value fixed to 1 and a corner magnitude estimated with the bigger events in the catalogs. For each seismogenic fault provided by the Database of the Individual Seismogenic Sources (DISS), we computed the annual rate (for each cells of 0.1°x0.1°) for magnitude bin of 0.1 units, assuming that the seismic moments of the earthquakes generated by each fault are distributed according to the same tapered Gutenberg-Richter relation of the smoothed seismicity model. The annual rate for the final model was determined in the following way: if the cell falls within one of the seismic sources, we merge the respective value of rate determined by the seismic moments of the earthquakes generated by each fault and the value of the smoothed seismicity model with the same weight; if instead the cells fall outside of any seismic source we considered the rate obtained from the spatial smoothed seismicity. Here we present the final results of our study to be used for the new Italian seismic hazard map.

  14. Surprising judgments about robot drivers: Experiments on rising expectations and blaming humans

    Directory of Open Access Journals (Sweden)

    Peter Danielson

    2015-05-01

    Full Text Available N-Reasons is an experimental Internet survey platform designed to enhance public participation in applied ethics and policy. N-Reasons encourages individuals to generate reasons to support their judgments, and groups to converge on a common set of reasons pro and con various issues.  In the Robot Ethics Survey some of the reasons contributed surprising judgments about autonomous machines. Presented with a version of the trolley problem with an autonomous train as the agent, participants gave unexpected answers, revealing high expectations for the autonomous machine and shifting blame from the automated device to the humans in the scenario. Further experiments with a standard pair of human-only trolley problems refine these results. While showing the high expectations even when no autonomous machine is involved, human bystanders are only blamed in the machine case. A third experiment explicitly aimed at responsibility for driverless cars confirms our findings about shifting blame in the case of autonomous machine agents. We conclude methodologically that both results point to the power of an experimental survey based approach to public participation to explore surprising assumptions and judgments in applied ethics. However, both results also support using caution when interpreting survey results in ethics, demonstrating the importance of qualitative data to provide further context for evaluating judgments revealed by surveys. On the ethics side, the result about shifting blame to humans interacting with autonomous machines suggests caution about the unintended consequences of intuitive principles requiring human responsibility.http://dx.doi.org/10.5324/eip.v9i1.1727

  15. Delineation of seismic source zones based on seismicity parameters ...

    Indian Academy of Sciences (India)

    In the present study, an attempt has been made to delineate seismic source zones in the study area (south India) based on the seismicity parameters. Seismicity parameters and the maximum probable earthquake for these source zones were evaluated and were used in the hazard evaluation. The probabilistic evaluation of ...

  16. Russian regulatory approaches to seismic design and seismic analysis of NPP piping

    International Nuclear Information System (INIS)

    Kaliberda, Y.V.

    2003-01-01

    The paper presents an overview of Russian regulatory approaches to seismic design and seismic analysis of NPP piping. The paper is focused on categorization and seismic analysis of nuclear power plant items (piping, equipment, supports, valves, but not building structures). The paper outlines the current seismic recommendations, corresponding methods with the examples of calculation models. The paper considers calculation results of the mechanisms of dynamic behavior and the problems of developing a rational and economical approaches to seismic design and seismic protection. (author)

  17. Angola Seismicity MAP

    Science.gov (United States)

    Neto, F. A. P.; Franca, G.

    2014-12-01

    The purpose of this job was to study and document the Angola natural seismicity, establishment of the first database seismic data to facilitate consultation and search for information on seismic activity in the country. The study was conducted based on query reports produced by National Institute of Meteorology and Geophysics (INAMET) 1968 to 2014 with emphasis to the work presented by Moreira (1968), that defined six seismogenic zones from macro seismic data, with highlighting is Zone of Sá da Bandeira (Lubango)-Chibemba-Oncócua-Iona. This is the most important of Angola seismic zone, covering the epicentral Quihita and Iona regions, geologically characterized by transcontinental structure tectono-magmatic activation of the Mesozoic with the installation of a wide variety of intrusive rocks of ultrabasic-alkaline composition, basic and alkaline, kimberlites and carbonatites, strongly marked by intense tectonism, presenting with several faults and fractures (locally called corredor de Lucapa). The earthquake of May 9, 1948 reached intensity VI on the Mercalli-Sieberg scale (MCS) in the locality of Quihita, and seismic active of Iona January 15, 1964, the main shock hit the grade VI-VII. Although not having significant seismicity rate can not be neglected, the other five zone are: Cassongue-Ganda-Massano de Amorim; Lola-Quilengues-Caluquembe; Gago Coutinho-zone; Cuima-Cachingues-Cambândua; The Upper Zambezi zone. We also analyzed technical reports on the seismicity of the middle Kwanza produced by Hidroproekt (GAMEK) region as well as international seismic bulletins of the International Seismological Centre (ISC), United States Geological Survey (USGS), and these data served for instrumental location of the epicenters. All compiled information made possible the creation of the First datbase of seismic data for Angola, preparing the map of seismicity with the reconfirmation of the main seismic zones defined by Moreira (1968) and the identification of a new seismic

  18. France's seismic zoning

    International Nuclear Information System (INIS)

    Mohammadioun, B.

    1997-01-01

    In order to assess the seismic hazard in France in relation to nuclear plant siting, the CEA, EDF and the BRGM (Mine and Geology Bureau) have carried out a collaboration which resulted in a seismic-tectonic map of France and a data base on seismic history (SIRENE). These studies were completed with a seismic-tectonic zoning, taking into account a very long period of time, that enabled a probabilistic evaluation of the seismic hazard in France, and that may be related to adjacent country hazard maps

  19. Seismic Noise Analysis and Reduction through Utilization of Collocated Seismic and Atmospheric Sensors at the GRO Chile Seismic Network

    Science.gov (United States)

    Farrell, M. E.; Russo, R. M.

    2013-12-01

    The installation of Earthscope Transportable Array-style geophysical observatories in Chile expands open data seismic recording capabilities in the southern hemisphere by nearly 30%, and has nearly tripled the number of seismic stations providing freely-available data in southern South America. Through the use of collocated seismic and atmospheric sensors at these stations we are able to analyze how local atmospheric conditions generate seismic noise, which can degrade data in seismic frequency bands at stations in the ';roaring forties' (S latitudes). Seismic vaults that are climate-controlled and insulated from the local environment are now employed throughout the world in an attempt to isolate seismometers from as many noise sources as possible. However, this is an expensive solution that is neither practical nor possible for all seismic deployments; and also, the increasing number and scope of temporary seismic deployments has resulted in the collection and archiving of terabytes of seismic data that is affected to some degree by natural seismic noise sources such as wind and atmospheric pressure changes. Changing air pressure can result in a depression and subsequent rebound of Earth's surface - which generates low frequency noise in seismic frequency bands - and even moderate winds can apply enough force to ground-coupled structures or to the surface above the seismometers themselves, resulting in significant noise. The 10 stations of the permanent Geophysical Reporting Observatories (GRO Chile), jointly installed during 2011-12 by IRIS and the Chilean Servicio Sismológico, include instrumentation in addition to the standard three seismic components. These stations, spaced approximately 300 km apart along the length of the country, continuously record a variety of atmospheric data including infrasound, air pressure, wind speed, and wind direction. The collocated seismic and atmospheric sensors at each station allow us to analyze both datasets together, to

  20. Seismic re-evaluation of Mochovce nuclear power plant. Seismic reevaluation of civil structures

    International Nuclear Information System (INIS)

    Podrouzek, P.

    1997-01-01

    In this contribution, an overview of seismic design procedures used for reassessment of seismic safety of civil structures at the Mochovce NPP in Slovak Republic presented. As an introduction, the objectives, history, and current status of seismic design of the NPP have been explained. General philosophy of design methods, seismic classification of buildings, seismic data, calculation methods, assumptions on structural behavior under seismic loading and reliability assessment were described in detail in the subsequent section. Examples of calculation models used for dynamic calculations of seismic response are given in the last section. (author)

  1. Role of seismic PRA in seismic safety decisions of nuclear power plants

    International Nuclear Information System (INIS)

    Ravindra, M.K.; Kennedy, R.P.; Sues, R.H.

    1985-01-01

    This paper highlights the important roles that seismic probabilistic risk assessments (PRAs) can play in the seismic safety decisions of nuclear power plants. If a seismic PRA has been performed for a plant, its results can be utilized to evaluate the seismic capability beyond the safe shutdown event (SSE). Seismic fragilities of key structures and equipment, fragilities of dominant plant damage states and the frequencies of occurrence of these plant damage states are reviewed to establish the seismic safety of the plant beyond the SSE level. Guidelines for seismic margin reviews and upgrading may be developed by first identifying the generic classes of structures and equipment that have been shown to be dominant risk contributors in the completed seismic PRAs, studying the underlying causes for their contribution and examining why certain other items (e.g., piping) have not proved to be high-risk-contributors

  2. Comparison of seismic margin assessment and probabilistic risk assessment in seismic IPE

    International Nuclear Information System (INIS)

    Reed, J.W.; Kassawara, R.P.

    1993-01-01

    A comparison of technical requirements and managerial issues between seismic margin assessment (SMA) and seismic probabilistic risk assessment (SPRA) in a seismic Individual Plant Examination (IPE) is presented and related to requirements for an Unresolved Safety Issue (USI) A-46 review which is required for older nuclear power plants. Advantages and disadvantages are discussed for each approach. Technical requirements reviewed for a seismic IPE include: scope of plants covered, seismic input, scope of review, selection of equipment, required experience and training of engineers, walkdown procedure, evaluation of components, relay review, containment review, quality assurance, products, documentation requirements, and closure procedure. Managerial issues discussed include regulatory acceptability, compatibility with seismic IPE, compliance with seismic IPE requirements, ease of use by utilities, and relative cost

  3. Evaluation of induced seismicity forecast models in the Induced Seismicity Test Bench

    Science.gov (United States)

    Király, Eszter; Gischig, Valentin; Zechar, Jeremy; Doetsch, Joseph; Karvounis, Dimitrios; Wiemer, Stefan

    2016-04-01

    Induced earthquakes often accompany fluid injection, and the seismic hazard they pose threatens various underground engineering projects. Models to monitor and control induced seismic hazard with traffic light systems should be probabilistic, forward-looking, and updated as new data arrive. Here, we propose an Induced Seismicity Test Bench to test and rank such models. We apply the test bench to data from the Basel 2006 and Soultz-sous-Forêts 2004 geothermal stimulation projects, and we assess forecasts from two models that incorporate a different mix of physical understanding and stochastic representation of the induced sequences: Shapiro in Space (SiS) and Hydraulics and Seismics (HySei). SiS is based on three pillars: the seismicity rate is computed with help of the seismogenic index and a simple exponential decay of the seismicity; the magnitude distribution follows the Gutenberg-Richter relation; and seismicity is distributed in space based on smoothing seismicity during the learning period with 3D Gaussian kernels. The HySei model describes seismicity triggered by pressure diffusion with irreversible permeability enhancement. Our results show that neither model is fully superior to the other. HySei forecasts the seismicity rate well, but is only mediocre at forecasting the spatial distribution. On the other hand, SiS forecasts the spatial distribution well but not the seismicity rate. The shut-in phase is a difficult moment for both models in both reservoirs: the models tend to underpredict the seismicity rate around, and shortly after, shut-in. Ensemble models that combine HySei's rate forecast with SiS's spatial forecast outperform each individual model.

  4. Automatic microseismic event picking via unsupervised machine learning

    Science.gov (United States)

    Chen, Yangkang

    2018-01-01

    Effective and efficient arrival picking plays an important role in microseismic and earthquake data processing and imaging. Widely used short-term-average long-term-average ratio (STA/LTA) based arrival picking algorithms suffer from the sensitivity to moderate-to-strong random ambient noise. To make the state-of-the-art arrival picking approaches effective, microseismic data need to be first pre-processed, for example, removing sufficient amount of noise, and second analysed by arrival pickers. To conquer the noise issue in arrival picking for weak microseismic or earthquake event, I leverage the machine learning techniques to help recognizing seismic waveforms in microseismic or earthquake data. Because of the dependency of supervised machine learning algorithm on large volume of well-designed training data, I utilize an unsupervised machine learning algorithm to help cluster the time samples into two groups, that is, waveform points and non-waveform points. The fuzzy clustering algorithm has been demonstrated to be effective for such purpose. A group of synthetic, real microseismic and earthquake data sets with different levels of complexity show that the proposed method is much more robust than the state-of-the-art STA/LTA method in picking microseismic events, even in the case of moderately strong background noise.

  5. Comparison of seismic sources for shallow seismic: sledgehammer and pyrotechnics

    Directory of Open Access Journals (Sweden)

    Brom Aleksander

    2015-10-01

    Full Text Available The pyrotechnic materials are one of the types of the explosives materials which produce thermal, luminous or sound effects, gas, smoke and their combination as a result of a self-sustaining chemical reaction. Therefore, pyrotechnics can be used as a seismic source that is designed to release accumulated energy in a form of seismic wave recorded by tremor sensors (geophones after its passage through the rock mass. The aim of this paper was to determine the utility of pyrotechnics for shallow seismic engineering. The work presented comparing the conventional method of seismic wave excitation for seismic refraction method like plate and hammer and activating of firecrackers on the surface. The energy released by various sources and frequency spectra was compared for the two types of sources. The obtained results did not determine which sources gave the better results but showed very interesting aspects of using pyrotechnics in seismic measurements for example the use of pyrotechnic materials in MASW.

  6. Post-seismic relaxation from geodetic and seismic data

    Directory of Open Access Journals (Sweden)

    Mikhail V. Rodkin

    2017-01-01

    Full Text Available We have examined the aftershock sequence and the post-seismic deformation process of the Parkfield earthquake (2004, M = 6, California, USA source area using GPS data. This event was chosen because of the possibility of joint analysis of data from the rather dense local GPS network (from SOPAC Internet archive and of the availability of the rather detailed aftershock sequence data (http://www.ncedc.org/ncedc/catalog-search.html. The relaxation process of post-seismic deformation prolongs about the same 400 days as the seismic aftershock process does. Thus, the aftershock process and the relaxation process in deformation could be the different sides of the same process. It should be noted that the ratio of the released seismic energy and of the GPS obtained deformation is quite different for the main shock and for the aftershock stage. The ratio of the released seismic energy to the deformation value decreases essentially for the post-shock process. The similar change in the seismic energy/deformation value ratio is valid in a few other strong earthquakes. Thus, this decrease seems typical of aftershock sequences testifying for decrease of ratio of elastic to inelastic deformation in the process of post-shock relaxation when the source area appears to be mostly fractured after the main shock occurs, but the healing process had no yet sufficient time to develop.

  7. Seismic texture classification. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vinther, R.

    1997-12-31

    The seismic texture classification method, is a seismic attribute that can both recognize the general reflectivity styles and locate variations from these. The seismic texture classification performs a statistic analysis for the seismic section (or volume) aiming at describing the reflectivity. Based on a set of reference reflectivities the seismic textures are classified. The result of the seismic texture classification is a display of seismic texture categories showing both the styles of reflectivity from the reference set and interpolations and extrapolations from these. The display is interpreted as statistical variations in the seismic data. The seismic texture classification is applied to seismic sections and volumes from the Danish North Sea representing both horizontal stratifications and salt diapers. The attribute succeeded in recognizing both general structure of successions and variations from these. Also, the seismic texture classification is not only able to display variations in prospective areas (1-7 sec. TWT) but can also be applied to deep seismic sections. The seismic texture classification is tested on a deep reflection seismic section (13-18 sec. TWT) from the Baltic Sea. Applied to this section the seismic texture classification succeeded in locating the Moho, which could not be located using conventional interpretation tools. The seismic texture classification is a seismic attribute which can display general reflectivity styles and deviations from these and enhance variations not found by conventional interpretation tools. (LN)

  8. Recent Vs. Historical Seismicity Analysis For Banat Seismic Region (Western Part Of Romania)

    OpenAIRE

    Oros Eugen; Diaconescu Mihai

    2015-01-01

    The present day seismic activity from a region reflects the active tectonics and can confirm the seismic potential of the seismogenic sources as they are modelled using the historical seismicity. This paper makes a comparative analysis of the last decade seismicity recorded in the Banat Seismic Region (western part of Romania) and the historical seismicity of the region (Mw≥4.0). Four significant earthquake sequences have been recently localized in the region, three of them nearby the city of...

  9. Lifting devices in nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The regulation applies to lifts, cranes, winches, rail trolleys, load pick-up equipment and fuel charging machines for LWR reactors, as far as these are employed in plants for the production or fission of nuclear fuels or for the reprocessing of spent nuclear fuels or for the storage or other uses of nuclear fuels. (orig.) 891 HP [de

  10. Seismic prediction ahead of tunnel constructions

    Science.gov (United States)

    Jetschny, S.; Bohlen, T.; Nil, D. D.; Giese, R.

    2007-12-01

    To increase safety and efficiency of tunnel constructions, online seismic exploration ahead of a tunnel can become a valuable tool. Within the \\it OnSite project founded by the BMBF (German Ministry of Education and Research) within \\it GeoTechnologien a new forward looking seismic imaging technique is developed to e.g. determine weak and water bearing zones ahead of the constructions. Our approach is based on the excitation and registration of \\it tunnel surface waves. These waves are excited at the tunnel face behind the cutter head of a tunnel boring machine and travel into drilling direction. Arriving at the front face they generate body waves (mainly S-waves) propagating further ahead. Reflected S-waves are back- converted into tunnel surface waves. For a theoretical description of the conversion process and for finding optimal acquisition geometries it is of importance to study the propagation characteristics of tunnel surface waves. 3D seismic finite difference modeling and analytic solutions of the wave equation in cylindric coordinates revealed that at higher frequencies, i.e. if the tunnel diameter is significantly larger than the wavelength of S-waves, these surface waves can be regarded as Rayleigh-waves circulating the tunnel. For smaller frequencies, i.e. when the S-wavelength approaches the tunnel diameter, the propagation characteristics of these surface waves are then similar to S- waves. Field measurements performed by the GeoForschungsZentrum Potsdam, Germany at the Gotthard Base Tunnel (Switzerland) show both effects, i.e. the propagation of Rayleigh- and body-wave like waves along the tunnel. To enhance our understanding of the excitation and propagation characteristics of tunnel surface waves the transition of Rayleigh to tube-waves waves is investigated both analytically and by numerical simulations.

  11. Seismic changes industry

    International Nuclear Information System (INIS)

    Taylor, G.

    1992-01-01

    This paper discusses the growth in the seismic industry as a result of the recent increases in the foreign market. With the decline of communism and the opening of Latin America to exploration, seismic teams have moved out into these areas in support of the oil and gas industry. The paper goes on to discuss the improved technology available for seismic resolution and the subsequent use of computers to field-proof the data while the seismic team is still on-site. It also discusses the effects of new computer technology on reducing the amount of support staff that is required to both conduct and interpret seismic information

  12. Automated classification of seismic sources in a large database: a comparison of Random Forests and Deep Neural Networks.

    Science.gov (United States)

    Hibert, Clement; Stumpf, André; Provost, Floriane; Malet, Jean-Philippe

    2017-04-01

    In the past decades, the increasing quality of seismic sensors and capability to transfer remotely large quantity of data led to a fast densification of local, regional and global seismic networks for near real-time monitoring of crustal and surface processes. This technological advance permits the use of seismology to document geological and natural/anthropogenic processes (volcanoes, ice-calving, landslides, snow and rock avalanches, geothermal fields), but also led to an ever-growing quantity of seismic data. This wealth of seismic data makes the construction of complete seismicity catalogs, which include earthquakes but also other sources of seismic waves, more challenging and very time-consuming as this critical pre-processing stage is classically done by human operators and because hundreds of thousands of seismic signals have to be processed. To overcome this issue, the development of automatic methods for the processing of continuous seismic data appears to be a necessity. The classification algorithm should satisfy the need of a method that is robust, precise and versatile enough to be deployed to monitor the seismicity in very different contexts. In this study, we evaluate the ability of machine learning algorithms for the analysis of seismic sources at the Piton de la Fournaise volcano being Random Forest and Deep Neural Network classifiers. We gather a catalog of more than 20,000 events, belonging to 8 classes of seismic sources. We define 60 attributes, based on the waveform, the frequency content and the polarization of the seismic waves, to parameterize the seismic signals recorded. We show that both algorithms provide similar positive classification rates, with values exceeding 90% of the events. When trained with a sufficient number of events, the rate of positive identification can reach 99%. These very high rates of positive identification open the perspective of an operational implementation of these algorithms for near-real time monitoring of

  13. National Seismic Station

    International Nuclear Information System (INIS)

    Stokes, P.A.

    1982-06-01

    The National Seismic Station was developed to meet the needs of regional or worldwide seismic monitoring of underground nuclear explosions to verify compliance with a nuclear test ban treaty. The Station acquires broadband seismic data and transmits it via satellite to a data center. It is capable of unattended operation for periods of at least a year, and will detect any tampering that could result in the transmission of unauthentic seismic data

  14. Overview of seismic margin insights gained from seismic PRA results

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Sues, R.H.; Campbell, R.D.

    1986-01-01

    This paper presents the findings of a study conducted under NRC and EPRI sponsorship in which published seismic PRAs were reviewed in order to gain insight to the seismic margins inherent in existing nuclear plants. The approach taken was to examine the fragilities of those components which have been found to be dominant contributors to seismic risk at plants in low-to-moderate seismic regions (SSE levels between 0.12g and 0.25g). It is concluded that there is significant margin inherent in the capacity of most critical components above the plant design basis. For ground motions less than about 0.3g, the predominant sources of seismic risk are loss of offsite power coupled with random failure of the emergency diesels, non-recoverable circuit breaker trip due to relay chatter, unanchored equipment, unreinforced non-load bearing block walls, vertical water storage tanks, systems interactions and possibly soil liquefaction. Recommendations as to which components should be reviewed in seismic margin studies for margin earthquakes less than 0.3g, between 0.3g and 0.5g, and greater than 0.5g, developed by the NRC expert panel on the quantification of seismic margins (based on the review of past PRA data, earthquake experience data, and their own personal experience) are presented

  15. Adding seismic broadband analysis to characterize Andean backarc seismicity in Argentina

    Science.gov (United States)

    Alvarado, P.; Giuliano, A.; Beck, S.; Zandt, G.

    2007-05-01

    Characterization of the highly seismically active Andean backarc is crucial for assessment of earthquake hazards in western Argentina. Moderate-to-large crustal earthquakes have caused several deaths, damage and drastic economic consequences in Argentinean history. We have studied the Andean backarc crust between 30°S and 36°S using seismic broadband data available from a previous ("the CHARGE") IRIS-PASSCAL experiment. We collected more than 12 terabytes of continuous seismic data from 22 broadband instruments deployed across Chile and Argentina during 1.5 years. Using free software we modeled full regional broadband waveforms and obtained seismic moment tensor inversions of crustal earthquakes testing for the best focal depth for each event. We also mapped differences in the Andean backarc crustal structure and found a clear correlation with different types of crustal seismicity (i.e. focal depths, focal mechanisms, magnitudes and frequencies of occurrence) and previously mapped terrane boundaries. We now plan to use the same methodology to study other regions in Argentina using near-real time broadband data available from the national seismic (INPRES) network and global seismic networks operating in the region. We will re-design the national seismic network to optimize short-period and broadband seismic station coverage for different network purposes. This work is an international effort that involves researchers and students from universities and national government agencies with the goal of providing more information about earthquake hazards in western Argentina.

  16. Seismic failure modes and seismic safety of Hardfill dam

    Directory of Open Access Journals (Sweden)

    Kun Xiong

    2013-04-01

    Full Text Available Based on microscopic damage theory and the finite element method, and using the Weibull distribution to characterize the random distribution of the mechanical properties of materials, the seismic response of a typical Hardfill dam was analyzed through numerical simulation during the earthquakes with intensities of 8 degrees and even greater. The seismic failure modes and failure mechanism of the dam were explored as well. Numerical results show that the Hardfill dam remains at a low stress level and undamaged or slightly damaged during an earthquake with an intensity of 8 degrees. During overload earthquakes, tensile cracks occur at the dam surfaces and extend to inside the dam body, and the upstream dam body experiences more serious damage than the downstream dam body. Therefore, under the seismic conditions, the failure pattern of the Hardfill dam is the tensile fracture of the upstream regions and the dam toe. Compared with traditional gravity dams, Hardfill dams have better seismic performance and greater seismic safety.

  17. Seismic Response Prediction of Buildings with Base Isolation Using Advanced Soft Computing Approaches

    Directory of Open Access Journals (Sweden)

    Mosbeh R. Kaloop

    2017-01-01

    Full Text Available Modeling response of structures under seismic loads is an important factor in Civil Engineering as it crucially affects the design and management of structures, especially for the high-risk areas. In this study, novel applications of advanced soft computing techniques are utilized for predicting the behavior of centrically braced frame (CBF buildings with lead-rubber bearing (LRB isolation system under ground motion effects. These techniques include least square support vector machine (LSSVM, wavelet neural networks (WNN, and adaptive neurofuzzy inference system (ANFIS along with wavelet denoising. The simulation of a 2D frame model and eight ground motions are considered in this study to evaluate the prediction models. The comparison results indicate that the least square support vector machine is superior to other techniques in estimating the behavior of smart structures.

  18. User's manual for seismic analysis code 'SONATINA-2V'

    International Nuclear Information System (INIS)

    Hanawa, Satoshi; Iyoku, Tatsuo

    2001-08-01

    The seismic analysis code, SONATINA-2V, has been developed to analyze the behavior of the HTTR core graphite components under seismic excitation. The SONATINA-2V code is a two-dimensional computer program capable of analyzing the vertical arrangement of the HTTR graphite components, such as fuel blocks, replaceable reflector blocks, permanent reflector blocks, as well as their restraint structures. In the analytical model, each block is treated as rigid body and is restrained by dowel pins which restrict relative horizontal movement but allow vertical and rocking motions between upper and lower blocks. Moreover, the SONATINA-2V code is capable of analyzing the core vibration behavior under both simultaneous excitations of vertical and horizontal directions. The SONATINA-2V code is composed of the main program, pri-processor for making the input data to SONATINA-2V and post-processor for data processing and making the graphics from analytical results. Though the SONATINA-2V code was developed in order to work in the MSP computer system of Japan Atomic Energy Research Institute (JAERI), the computer system was abolished with the technical progress of computer. Therefore, improvement of this analysis code was carried out in order to operate the code under the UNIX machine, SR8000 computer system, of the JAERI. The users manual for seismic analysis code, SONATINA-2V, including pri- and post-processor is given in the present report. (author)

  19. Early estimation of epicenter seismic intensities according to co-seismic deformation

    OpenAIRE

    Weidong, Li; Chaojun, Zhang; Dahui, Li; Jiayong, He; Huizhong, Chen; Lomnitz, Cinna

    2010-01-01

    The absolute fault displacement in co-seismic deformation is derived assuming that location, depth, faulting mechanism and magnitude of the earthquake are known. The 2008 Wenchuan earthquake (M8.0) is used as an example to determine the distribution of seismic intensities using absolute displacement and a crustal model. We fnd that an early prediction of the distribution of seismic intensities after a large earthquake may be performed from the estimated absolute co-seismic displacements using...

  20. Structural analysis of a rehabilitative training system based on a ceiling rail for safety of hemiplegia patients.

    Science.gov (United States)

    Kim, Kyong; Song, Won Kyung; Chong, Woo Suk; Yu, Chang Ho

    2018-04-17

    The body-weight support (BWS) function, which helps to decrease load stresses on a user, is an effective tool for gait and balance rehabilitation training for elderly people with weakened lower-extremity muscular strength, hemiplegic patients, etc. This study conducts structural analysis to secure user safety in order to develop a rail-type gait and balance rehabilitation training system (RRTS). The RRTS comprises a rail, trolley, and brain-machine interface. The rail (platform) is connected to the ceiling structure, bearing the loads of the RRTS and of the user and allowing locomobility. The trolley consists of a smart drive unit (SDU) that assists the user with forward and backward mobility and a body-weight support (BWS) unit that helps the user to control his/her body-weight load, depending on the severity of his/her hemiplegia. The brain-machine interface estimates and measures on a real-time basis the body-weight (load) of the user and the intended direction of his/her movement. Considering the weight of the system and the user, the mechanical safety performance of the system frame under an applied 250-kg static load is verified through structural analysis using ABAQUS (6.14-3) software. The maximum stresses applied on the rail and trolley under the given gravity load of 250 kg, respectively, are 18.52 MPa and 48.44 MPa. The respective safety factors are computed to be 7.83 and 5.26, confirming the RRTS's mechanical safety. An RRTS with verified structural safety could be utilized for gait movement and balance rehabilitation and training for patients with hemiplegia.

  1. Causality between expansion of seismic cloud and maximum magnitude of induced seismicity in geothermal field

    Science.gov (United States)

    Mukuhira, Yusuke; Asanuma, Hiroshi; Ito, Takatoshi; Häring, Markus

    2016-04-01

    Occurrence of induced seismicity with large magnitude is critical environmental issues associated with fluid injection for shale gas/oil extraction, waste water disposal, carbon capture and storage, and engineered geothermal systems (EGS). Studies for prediction of the hazardous seismicity and risk assessment of induced seismicity has been activated recently. Many of these studies are based on the seismological statistics and these models use the information of the occurrence time and event magnitude. We have originally developed physics based model named "possible seismic moment model" to evaluate seismic activity and assess seismic moment which can be ready to release. This model is totally based on microseismic information of occurrence time, hypocenter location and magnitude (seismic moment). This model assumes existence of representative parameter having physical meaning that release-able seismic moment per rock volume (seismic moment density) at given field. Seismic moment density is to be estimated from microseismic distribution and their seismic moment. In addition to this, stimulated rock volume is also inferred by progress of microseismic cloud at given time and this quantity can be interpreted as the rock volume which can release seismic energy due to weakening effect of normal stress by injected fluid. Product of these two parameters (equation (1)) provide possible seismic moment which can be released from current stimulated zone as a model output. Difference between output of this model and observed cumulative seismic moment corresponds the seismic moment which will be released in future, based on current stimulation conditions. This value can be translated into possible maximum magnitude of induced seismicity in future. As this way, possible seismic moment can be used to have feedback to hydraulic stimulation operation in real time as an index which can be interpreted easily and intuitively. Possible seismic moment is defined as equation (1), where D

  2. Seismic Studies

    Energy Technology Data Exchange (ETDEWEB)

    R. Quittmeyer

    2006-09-25

    This technical work plan (TWP) describes the efforts to develop and confirm seismic ground motion inputs used for preclosure design and probabilistic safety 'analyses and to assess the postclosure performance of a repository at Yucca Mountain, Nevada. As part of the effort to develop seismic inputs, the TWP covers testing and analyses that provide the technical basis for inputs to the seismic ground-motion site-response model. The TWP also addresses preparation of a seismic methodology report for submission to the U.S. Nuclear Regulatory Commission (NRC). The activities discussed in this TWP are planned for fiscal years (FY) 2006 through 2008. Some of the work enhances the technical basis for previously developed seismic inputs and reduces uncertainties and conservatism used in previous analyses and modeling. These activities support the defense of a license application. Other activities provide new results that will support development of the preclosure, safety case; these results directly support and will be included in the license application. Table 1 indicates which activities support the license application and which support licensing defense. The activities are listed in Section 1.2; the methods and approaches used to implement them are discussed in more detail in Section 2.2. Technical and performance objectives of this work scope are: (1) For annual ground motion exceedance probabilities appropriate for preclosure design analyses, provide site-specific seismic design acceleration response spectra for a range of damping values; strain-compatible soil properties; peak motions, strains, and curvatures as a function of depth; and time histories (acceleration, velocity, and displacement). Provide seismic design inputs for the waste emplacement level and for surface sites. Results should be consistent with the probabilistic seismic hazard analysis (PSHA) for Yucca Mountain and reflect, as appropriate, available knowledge on the limits to extreme ground

  3. Seismic Studies

    International Nuclear Information System (INIS)

    R. Quittmeyer

    2006-01-01

    This technical work plan (TWP) describes the efforts to develop and confirm seismic ground motion inputs used for preclosure design and probabilistic safety 'analyses and to assess the postclosure performance of a repository at Yucca Mountain, Nevada. As part of the effort to develop seismic inputs, the TWP covers testing and analyses that provide the technical basis for inputs to the seismic ground-motion site-response model. The TWP also addresses preparation of a seismic methodology report for submission to the U.S. Nuclear Regulatory Commission (NRC). The activities discussed in this TWP are planned for fiscal years (FY) 2006 through 2008. Some of the work enhances the technical basis for previously developed seismic inputs and reduces uncertainties and conservatism used in previous analyses and modeling. These activities support the defense of a license application. Other activities provide new results that will support development of the preclosure, safety case; these results directly support and will be included in the license application. Table 1 indicates which activities support the license application and which support licensing defense. The activities are listed in Section 1.2; the methods and approaches used to implement them are discussed in more detail in Section 2.2. Technical and performance objectives of this work scope are: (1) For annual ground motion exceedance probabilities appropriate for preclosure design analyses, provide site-specific seismic design acceleration response spectra for a range of damping values; strain-compatible soil properties; peak motions, strains, and curvatures as a function of depth; and time histories (acceleration, velocity, and displacement). Provide seismic design inputs for the waste emplacement level and for surface sites. Results should be consistent with the probabilistic seismic hazard analysis (PSHA) for Yucca Mountain and reflect, as appropriate, available knowledge on the limits to extreme ground motion at

  4. Using Seismic Interferometry to Investigate Seismic Swarms

    Science.gov (United States)

    Matzel, E.; Morency, C.; Templeton, D. C.

    2017-12-01

    Seismicity provides a direct means of measuring the physical characteristics of active tectonic features such as fault zones. Hundreds of small earthquakes often occur along a fault during a seismic swarm. This seismicity helps define the tectonically active region. When processed using novel geophysical techniques, we can isolate the energy sensitive to the fault, itself. Here we focus on two methods of seismic interferometry, ambient noise correlation (ANC) and the virtual seismometer method (VSM). ANC is based on the observation that the Earth's background noise includes coherent energy, which can be recovered by observing over long time periods and allowing the incoherent energy to cancel out. The cross correlation of ambient noise between a pair of stations results in a waveform that is identical to the seismogram that would result if an impulsive source located at one of the stations was recorded at the other, the Green function (GF). The calculation of the GF is often stable after a few weeks of continuous data correlation, any perturbations to the GF after that point are directly related to changes in the subsurface and can be used for 4D monitoring.VSM is a style of seismic interferometry that provides fast, precise, high frequency estimates of the Green's function (GF) between earthquakes. VSM illuminates the subsurface precisely where the pressures are changing and has the potential to image the evolution of seismicity over time, including changes in the style of faulting. With hundreds of earthquakes, we can calculate thousands of waveforms. At the same time, VSM collapses the computational domain, often by 2-3 orders of magnitude. This allows us to do high frequency 3D modeling in the fault region. Using data from a swarm of earthquakes near the Salton Sea, we demonstrate the power of these techniques, illustrating our ability to scale from the far field, where sources are well separated, to the near field where their locations fall within each other

  5. Seismic qualification of equipment

    International Nuclear Information System (INIS)

    Heidebrecht, A.C.; Tso, W.K.

    1983-03-01

    This report describes the results of an investigation into the seismic qualification of equipment located in CANDU nuclear power plants. It is particularly concerned with the evaluation of current seismic qualification requirements, the development of a suitable methodology for the seismic qualification of safety systems, and the evaluation of seismic qualification analysis and testing procedures

  6. Geomorphology and seismic risk

    Science.gov (United States)

    Panizza, Mario

    1991-07-01

    The author analyses the contributions provided by geomorphology in studies suited to the assessment of seismic risk: this is defined as function of the seismic hazard, of the seismic susceptibility, and of the vulnerability. The geomorphological studies applicable to seismic risk assessment can be divided into two sectors: (a) morpho-neotectonic investigations conducted to identify active tectonic structures; (b) geomorphological and morphometric analyses aimed at identifying the particular situations that amplify or reduce seismic susceptibility. The morpho-neotectonic studies lead to the identification, selection and classification of the lineaments that can be linked with active tectonic structures. The most important geomorphological situations that can condition seismic susceptibility are: slope angle, debris, morphology, degradational slopes, paleo-landslides and underground cavities.

  7. Internet-Based Solutions for a Secure and Efficient Seismic Network

    Science.gov (United States)

    Bhadha, R.; Black, M.; Bruton, C.; Hauksson, E.; Stubailo, I.; Watkins, M.; Alvarez, M.; Thomas, V.

    2017-12-01

    The Southern California Seismic Network (SCSN), operated by Caltech and USGS, leverages modern Internet-based computing technologies to provide timely earthquake early warning for damage reduction, event notification, ShakeMap, and other data products. Here we present recent and ongoing innovations in telemetry, security, cloud computing, virtualization, and data analysis that have allowed us to develop a network that runs securely and efficiently.Earthquake early warning systems must process seismic data within seconds of being recorded, and SCSN maintains a robust and resilient network of more than 350 digital strong motion and broadband seismic stations to achieve this goal. We have continued to improve the path diversity and fault tolerance within our network, and have also developed new tools for latency monitoring and archiving.Cyberattacks are in the news almost daily, and with most of our seismic data streams running over the Internet, it is only a matter of time before SCSN is targeted. To ensure system integrity and availability across our network, we have implemented strong security, including encryption and Virtual Private Networks (VPNs).SCSN operates its own data center at Caltech, but we have also installed real-time servers on Amazon Web Services (AWS), to provide an additional level of redundancy, and eventually to allow full off-site operations continuity for our network. Our AWS systems receive data from Caltech-based import servers and directly from field locations, and are able to process the seismic data, calculate earthquake locations and magnitudes, and distribute earthquake alerts, directly from the cloud.We have also begun a virtualization project at our Caltech data center, allowing us to serve data from Virtual Machines (VMs), making efficient use of high-performance hardware and increasing flexibility and scalability of our data processing systems.Finally, we have developed new monitoring of station average noise levels at most stations

  8. Seismic sequences in the Sombrero Seismic Zone

    Science.gov (United States)

    Pulliam, J.; Huerfano, V. A.; ten Brink, U.; von Hillebrandt, C.

    2007-05-01

    The northeastern Caribbean, in the vicinity of Puerto Rico and the Virgin Islands, has a long and well-documented history of devastating earthquakes and tsunamis, including major events in 1670, 1787, 1867, 1916, 1918, and 1943. Recently, seismicity has been concentrated to the north and west of the British Virgin Islands, in the region referred to as the Sombrero Seismic Zone by the Puerto Rico Seismic Network (PRSN). In the combined seismicity catalog maintained by the PRSN, several hundred small to moderate magnitude events can be found in this region prior to 2006. However, beginning in 2006 and continuing to the present, the rate of seismicity in the Sombrero suddenly increased, and a new locus of activity developed to the east of the previous location. Accurate estimates of seismic hazard, and the tsunamigenic potential of seismic events, depend on an accurate and comprehensive understanding of how strain is being accommodated in this corner region. Are faults locked and accumulating strain for release in a major event? Or is strain being released via slip over a diffuse system of faults? A careful analysis of seismicity patterns in the Sombrero region has the potential to both identify faults and modes of failure, provided the aggregation scheme is tuned to properly identify related events. To this end, we experimented with a scheme to identify seismic sequences based on physical and temporal proximity, under the assumptions that (a) events occur on related fault systems as stress is refocused by immediately previous events and (b) such 'stress waves' die out with time, so that two events that occur on the same system within a relatively short time window can be said to have a similar 'trigger' in ways that two nearby events that occurred years apart cannot. Patterns that emerge from the identification, temporal sequence, and refined locations of such sequences of events carry information about stress accommodation that is obscured by large clouds of

  9. Nuclear fuel element recovery using PEDSCO RMI Unit

    International Nuclear Information System (INIS)

    Martin, D.G.; Pedersen, B.V.

    1984-01-01

    In September 1982, a PEDSCO Remote Mobile Investigation Unit was used to recover damaged irradiated fuel elements from a fueling machine and trolley deck at Bruce Nuclear Generating Station 'A'. This Canadian-made remote controlled vehicle was originally designed for explosive ordinance disposal by law enforcement agencies. This paper describes its adaptation to nuclear service and its first mission, within a nuclear facility

  10. Patterns of Seismicity Associated with USGS Identified Areas of Potentially Induced Seismicity.

    Science.gov (United States)

    Barnes, Caitlin; Halihan, Todd

    2018-03-13

    A systematic review across U.S. Geological Survey (USGS) identified potentially induced seismic locations was conducted to discover seismic distance patterns and trends over time away from injection disposal wells. Previous research indicates a 10 km (6 miles) average where the majority of induced seismicity is expected to occur within individual locations, with some areas reporting a larger radius of 35 km (22 miles) to over 70 km (43 miles). This research analyzed earthquake occurrences within nine USGS locations where specified wells were identified as contributors to induced seismicity to determine distance patterns from disposal wells or outward seismic migration over time using established principles of hydrogeology. Results indicate a radius of 31.6 km (20 miles) where 90% of felt earthquakes occur among locations, with the closest proximal felt seismic events, on average, occurring 3 km (1.9 miles) away from injection disposal wells. The results of this research found distance trends across multiple locations of potentially induced seismicity. © 2018, National Ground Water Association.

  11. Seismic proving test of process computer systems with a seismic floor isolation system

    International Nuclear Information System (INIS)

    Fujimoto, S.; Niwa, H.; Kondo, H.

    1995-01-01

    The authors have carried out seismic proving tests for process computer systems as a Nuclear Power Engineering Corporation (NUPEC) project sponsored by the Ministry of International Trade and Industry (MITI). This paper presents the seismic test results for evaluating functional capabilities of process computer systems with a seismic floor isolation system. The seismic floor isolation system to isolate the horizontal motion was composed of a floor frame (13 m x 13 m), ball bearing units, and spring-damper units. A series of seismic excitation tests was carried out using a large-scale shaking table of NUPEC. From the test results, the functional capabilities during large earthquakes of computer systems with a seismic floor isolation system were verified

  12. Seismic gaps and plate tectonics: seismic potential for major boundaries

    Energy Technology Data Exchange (ETDEWEB)

    McCann, W R; Nishenko, S P; Sykes, L R; Krause, J

    1979-01-01

    The theory of plate tectonics provides a basic framework for evaluating the potential for future great earthquakes to occur along major plate boundaries. Along most of the transform and convergent plate boundaries considered in this paper, the majority of seismic slip occurs during large earthquakes, i.e., those of magnitude 7 or greater. The concepts that rupture zones, as delineated by aftershocks, tend to abut rather than overlap, and large events occur in regions with histories of both long-and short-term seismic quiescence are used in this paper to delineate major seismic gaps. The term seismic gap is taken to refer to any region along an active plate boundary that has not experienced a large thrust or strike-slip earthquake for more than 30 years. A region of high seismic potential is a seismic gap that, for historic or tectonic reasons, is considered likely to produce a large shock during the next few decades. The seismic gap technique provides estimates of the location, size of future events and origin time to within a few tens of years at best. The accompanying map summarizes six categories of seismic potential for major plate boundaries in and around the margins of the Pacific Ocean and the Caribbean, South Sandwich and Sunda (Indonesia) regions for the next few decades. These six categories are meant to be interpreted as forecasts of the location and size of future large shocks and should not be considered to be predictions in which a precise estimate of the time of occurrence is specified. The categories of potential assigned here provide a rationale for assigning priorities for instrumentation, for future studies aimed at predicting large earthquakes and for making estimates of tsunami potential.

  13. Recent Vs. Historical Seismicity Analysis For Banat Seismic Region (Western Part Of Romania

    Directory of Open Access Journals (Sweden)

    Oros Eugen

    2015-03-01

    Full Text Available The present day seismic activity from a region reflects the active tectonics and can confirm the seismic potential of the seismogenic sources as they are modelled using the historical seismicity. This paper makes a comparative analysis of the last decade seismicity recorded in the Banat Seismic Region (western part of Romania and the historical seismicity of the region (Mw≥4.0. Four significant earthquake sequences have been recently localized in the region, three of them nearby the city of Timisoara (January 2012 and March 2013 and the fourth within Hateg Basin, South Carpathians (October 2013. These sequences occurred within the epicentral areas of some strong historical earthquakes (Mw≥5.0. The main events had some macroseismic effects on people up to some few kilometers from the epicenters. Our results update the Romanian earthquakes catalogue and bring new information along the local seismic hazard sources models and seismotectonics.

  14. Delineation of seismic source zones based on seismicity parameters ...

    Indian Academy of Sciences (India)

    these source zones were evaluated and were used in the hazard evaluation. ... seismic sources, linear and areal, were considered in the present study to model the seismic sources in the ..... taken as an authentic reference manual for iden-.

  15. Micro-seismicity and seismic moment release within the Coso Geothermal Field, California

    Science.gov (United States)

    Kaven, Joern; Hickman, Stephen H.; Davatzes, Nicholas C.

    2014-01-01

    We relocate 16 years of seismicity in the Coso Geothermal Field (CGF) using differential travel times and simultaneously invert for seismic velocities to improve our knowledge of the subsurface geologic and hydrologic structure. We expand on our previous results by doubling the number of relocated events from April 1996 through May 2012 using a new field-wide 3-D velocity model. Relocated micro-seismicity sharpens in many portions of the active geothermal reservoir, likely defining large-scale fault zones and fluid pressure compartment boundaries. However, a significant fraction of seismicity remains diffuse and does not cluster into sharply defined structures, suggesting that permeability is maintained within the reservoir through distributed brittle failure. The seismic velocity structure reveals heterogeneous distributions of compressional (Vp) and shear (Vs) wave speed, with Vs generally higher in the Main Field and East Flank and Vp remaining relatively uniform across the CGF, but with significant local variations. The Vp/Vs ratio appears to outline the two main producing compartments of the reservoir at depths below mean ground level of approximately 1 to 2.5 km, with a ridge of relatively high Vp/Vs separating the Main Field from the East Flank. Detailed analyses of spatial and temporal variations in earthquake relocations and cumulative seismic moment release in the East Flank reveal three regions with persistently high rates of seismic activity. Two of these regions exhibit sharp, stationary boundaries at the margins of the East Flank that likely represent barriers to fluid flow and advective heat transport. However, seismicity and moment release in a third region at the northern end of the East Flank spread over time to form an elongated NE to SW structure, roughly parallel both to an elongated cluster of seismicity at the southern end of the East Flank and to regional fault traces mapped at the surface. Our results indicate that high

  16. Seismic Design of ITER Component Cooling Water System-1 Piping

    Science.gov (United States)

    Singh, Aditya P.; Jadhav, Mahesh; Sharma, Lalit K.; Gupta, Dinesh K.; Patel, Nirav; Ranjan, Rakesh; Gohil, Guman; Patel, Hiren; Dangi, Jinendra; Kumar, Mohit; Kumar, A. G. A.

    2017-04-01

    The successful performance of ITER machine very much depends upon the effective removal of heat from the in-vessel components and other auxiliary systems during Tokamak operation. This objective will be accomplished by the design of an effective Cooling Water System (CWS). The optimized piping layout design is an important element in CWS design and is one of the major design challenges owing to the factors of large thermal expansion and seismic accelerations; considering safety, accessibility and maintainability aspects. An important sub-system of ITER CWS, Component Cooling Water System-1 (CCWS-1) has very large diameter of pipes up to DN1600 with many intersections to fulfill the process flow requirements of clients for heat removal. Pipe intersection is the weakest link in the layout due to high stress intensification factor. CCWS-1 piping up to secondary confinement isolation valves as well as in-between these isolation valves need to survive a Seismic Level-2 (SL-2) earthquake during the Tokamak operation period to ensure structural stability of the system in the Safe Shutdown Earthquake (SSE) event. This paper presents the design, qualification and optimization of layout of ITER CCWS-1 loop to withstand SSE event combined with sustained and thermal loads as per the load combinations defined by ITER and allowable limits as per ASME B31.3, This paper also highlights the Modal and Response Spectrum Analyses done to find out the natural frequency and system behavior during the seismic event.

  17. Real Time Seismic Prediction while Drilling

    Science.gov (United States)

    Schilling, F. R.; Bohlen, T.; Edelmann, T.; Kassel, A.; Heim, A.; Gehring, M.; Lüth, S.; Giese, R.; Jaksch, K.; Rechlin, A.; Kopf, M.; Stahlmann, J.; Gattermann, J.; Bruns, B.

    2009-12-01

    Efficient and safe drilling is a prerequisite to enhance the mobility of people and goods, to improve the traffic as well as utility infrastructure of growing megacities, and to ensure the growing energy demand while building geothermal and in hydroelectric power plants. Construction within the underground is often building within the unknown. An enhanced risk potential for people and the underground building may arise if drilling enters fracture zones, karsts, brittle rocks, mixed solid and soft rocks, caves, or anthropogenic obstacles. Knowing about the material behavior ahead of the drilling allows reducing the risk during drilling and construction operation. In drilling operations direct observations from boreholes can be complemented with geophysical investigations. In this presentation we focus on “real time” seismic prediction while drilling which is seen as a prerequisite while using geophysical methods in modern drilling operations. In solid rocks P- and S-wave velocity, refraction and reflection as well as seismic wave attenuation can be used for the interpretation of structures ahead of the drilling. An Integrated Seismic Imaging System (ISIS) for exploration ahead of a construction is used, where a pneumatic hammer or a magnetostrictive vibration source generate repetitive signals behind the tunneling machine. Tube waves are generated which travel along the tunnel to the working face. There the tube waves are converted to mainly S- but also P-Waves which interact with the formation ahead of the heading face. The reflected or refracted waves travel back to the working front are converted back to tube waves and recorded using three-component geophones which are fit into the tips of anchor rods. In near real time, the ISIS software allows for an integrated 3D imaging and interpretation of the observed data, geological and geotechnical parameters. Fracture zones, heterogeneities, and variations in the rock properties can be revealed during the drilling

  18. Development of Canadian seismic design approach and overview of seismic standards

    Energy Technology Data Exchange (ETDEWEB)

    Usmani, A. [Amec Foster Wheeler, Toronto, ON (Canada); Aziz, T. [TSAziz Consulting Inc., Mississauga, ON (Canada)

    2015-07-01

    Historically the Canadian seismic design approaches have evolved for CANDU® nuclear power plants to ensure that they are designed to withstand a design basis earthquake (DBE) and have margins to meet the safety requirements of beyond DBE (BDBE). While the Canadian approach differs from others, it is comparable and in some cases more conservative. The seismic requirements are captured in five CSA nuclear standards which are kept up to date and incorporate lessons learnt from recent seismic events. This paper describes the evolution of Canadian approach, comparison with others and provides an overview and salient features of CSA seismic standards. (author)

  19. Analysis of machining and machine tools

    CERN Document Server

    Liang, Steven Y

    2016-01-01

    This book delivers the fundamental science and mechanics of machining and machine tools by presenting systematic and quantitative knowledge in the form of process mechanics and physics. It gives readers a solid command of machining science and engineering, and familiarizes them with the geometry and functionality requirements of creating parts and components in today’s markets. The authors address traditional machining topics, such as: single and multiple point cutting processes grinding components accuracy and metrology shear stress in cutting cutting temperature and analysis chatter They also address non-traditional machining, such as: electrical discharge machining electrochemical machining laser and electron beam machining A chapter on biomedical machining is also included. This book is appropriate for advanced undergraduate and graduate mechani cal engineering students, manufacturing engineers, and researchers. Each chapter contains examples, exercises and their solutions, and homework problems that re...

  20. Rescaled Range analysis of Induced Seismicity: rapid classification of clusters in seismic crisis

    Science.gov (United States)

    Bejar-Pizarro, M.; Perez Lopez, R.; Benito-Parejo, M.; Guardiola-Albert, C.; Herraiz, M.

    2017-12-01

    Different underground fluid operations, mainly gas storing, fracking and water pumping, can trigger Induced Seismicity (IS). This seismicity is normally featured by small-sized earthquakes (M<2.5), although particular cases reach magnitude as great as 5. It has been up for debate whether earthquakes greater than 5 can be triggered by IS or this level of magnitude only corresponds to tectonic earthquakes caused by stress change. Whatever the case, the characterization of IS for seismic clusters and seismic series recorded close but not into the gas storage, is still under discussion. Time-series of earthquakes obey non-linear patterns where the Hurst exponent describes the persistency or anti-persistency of the sequence. Natural seismic sequences have an H-exponent close to 0.7, which combined with the b-value time evolution during the time clusters, give us valuable information about the stationarity of the phenomena. Tectonic earthquakes consist in a main shock with a decay of time-occurrence of seismic shocks obeying the Omori's empirical law. On the contrary, IS does not exhibit a main shock and the time occurrence depends on the injection operations instead of on the tectonic energy released. In this context, the H-exponent can give information about the origin of the sequence. In 2013, a seismic crisis was declared from the Castor underground gas storing located off-shore in the Mediterranean Sea, close to the Northeastern Spanish cost. The greatest induced earthquake was 3.7. However, a 4.2 earthquake, probably of tectonic origin, occurred few days after the operations stopped. In this work, we have compared the H-exponent and the b-value time evolution according to the timeline of gas injection. Moreover, we have divided the seismic sequence into two groups: (1) Induced Seismicity and (2) Triggered Seismicity. The rescaled range analysis allows the differentiation between natural and induced seismicity and gives information about the persistency and long

  1. WWER NPPs fuel handling machine control system

    International Nuclear Information System (INIS)

    Mini, G.; Rossi, G.; Barabino, M.; Casalini, M.

    2001-01-01

    In order to increase the safety level of the fuel handling machine on WWER NPPs, Ansaldo Nucleare was asked to design and supply a new Control System. Two FHM Control System units have been already supplied for Temelin NPP and others supplies are in process for the Atommash company, which has in charge the supply of FHMs for NPPs located in Russia, Ukraine and China. The Fuel Handling Machine (FHM) Control System is an integrated system capable of a complete management of nuclear fuel assemblies. The computer-based system takes into account all the operational safety interlocks so that it is able to avoid incorrect and dangerous manoeuvres in the case of operator error. Control system design criteria, hardware and software architecture, and quality assurance control, are in accordance with the most recent international requirements and standards, and in particular for electromagnetic disturbance immunity demands and seismic compatibility. The hardware architecture of the control system is based on ABB INFI 90 system. The microprocessor-based ABB INFI 90 system incorporates and improves upon many of the time proven control capabilities of Bailey Network 90, validated over 14,000 installations world-wide. The control system complies all the former designed sensors and devices of the machine and markedly the angular position measurement sensors named 'selsyn' of Russian design. Nevertheless it is fully compatible with all the most recent sensors and devices currently available on the market (for ex. Multiturn absolute encoders). All control logic components were developed using standard INFI 90 Engineering Work Station, interconnecting blocks extracted from an extensive SAMA library by using a graphical approach (CAD) and allowing an easier intelligibility, more flexibility and updated and coherent documentation. The data acquisition system and the Man Machine Interface are implemented by ABB in co-operation with Ansaldo. The flexible and powerful software structure

  2. VVER NPPs fuel handling machine control system

    International Nuclear Information System (INIS)

    Mini, G.; Rossi, G.; Barabino, M.; Casalini, M.

    2002-01-01

    In order to increase the safety level of the fuel handling machine on WWER NPPs, Ansaldo Nucleare was asked to design and supply a new Control System. Two Fuel Handling Machine (FHM) Control System units have been already supplied for Temelin NPP and others supply are in process for the Atommash company, which has in charge the supply of FHMs for NPPs located in Russia, Ukraine and China.The computer-based system takes into account all the operational safety interlocks so that it is able to avoid incorrect and dangerous manoeuvres in the case of operator error. Control system design criteria, hardware and software architecture, and quality assurance control, are in accordance with the most recent international requirements and standards, and in particular for electromagnetic disturbance immunity demands and seismic compatibility. The hardware architecture of the control system is based on ABB INFI 90 system. The microprocessor-based ABB INFI 90 system incorporates and improves upon many of the time proven control capabilities of Bailey Network 90, validated over 14,000 installations world-wide.The control system complies all the former designed sensors and devices of the machine and markedly the angular position measurement sensors named 'selsyn' of Russian design. Nevertheless it is fully compatible with all the most recent sensors and devices currently available on the market (for ex. Multiturn absolute encoders).All control logic were developed using standard INFI 90 Engineering Work Station, interconnecting blocks extracted from an extensive SAMA library by using a graphical approach (CAD) and allowing and easier intelligibility, more flexibility and updated and coherent documentation. The data acquisition system and the Man Machine Interface are implemented by ABB in co-operation with Ansaldo. The flexible and powerful software structure of 1090 Work-stations (APMS - Advanced Plant Monitoring System, or Tenore NT) has been successfully used to interface the

  3. Seismic intrusion detector system

    Science.gov (United States)

    Hawk, Hervey L.; Hawley, James G.; Portlock, John M.; Scheibner, James E.

    1976-01-01

    A system for monitoring man-associated seismic movements within a control area including a geophone for generating an electrical signal in response to seismic movement, a bandpass amplifier and threshold detector for eliminating unwanted signals, pulse counting system for counting and storing the number of seismic movements within the area, and a monitoring system operable on command having a variable frequency oscillator generating an audio frequency signal proportional to the number of said seismic movements.

  4. Quantitative Seismic Amplitude Analysis

    NARCIS (Netherlands)

    Dey, A.K.

    2011-01-01

    The Seismic Value Chain quantifies the cyclic interaction between seismic acquisition, imaging and reservoir characterization. Modern seismic innovation to address the global imbalance in hydrocarbon supply and demand requires such cyclic interaction of both feed-forward and feed-back processes.

  5. Seismic Design of a Single Bored Tunnel: Longitudinal Deformations and Seismic Joints

    Science.gov (United States)

    Oh, J.; Moon, T.

    2018-03-01

    The large diameter bored tunnel passing through rock and alluvial deposits subjected to seismic loading is analyzed for estimating longitudinal deformations and member forces on the segmental tunnel liners. The project site has challenges including high hydrostatic pressure, variable ground profile and high seismic loading. To ensure the safety of segmental tunnel liner from the seismic demands, the performance-based two-level design earthquake approach, Functional Evaluation Earthquake and Safety Evaluation Earthquake, has been adopted. The longitudinal tunnel and ground response seismic analyses are performed using a three-dimensional quasi-static linear elastic and nonlinear elastic discrete beam-spring elements to represent segmental liner and ground spring, respectively. Three components (longitudinal, transverse and vertical) of free-field ground displacement-time histories evaluated from site response analyses considering wave passage effects have been applied at the end support of the strain-compatible ground springs. The result of the longitudinal seismic analyses suggests that seismic joint for the mitigation measure requiring the design deflection capacity of 5-7.5 cm is to be furnished at the transition zone between hard and soft ground condition where the maximum member forces on the segmental liner (i.e., axial, shear forces and bending moments) are induced. The paper illustrates how detailed numerical analyses can be practically applied to evaluate the axial and curvature deformations along the tunnel alignment under difficult ground conditions and to provide the seismic joints at proper locations to effectively reduce the seismic demands below the allowable levels.

  6. Approximate Seismic Diffusive Models of Near-Receiver Geology: Applications from Lab Scale to Field

    Science.gov (United States)

    King, Thomas; Benson, Philip; De Siena, Luca; Vinciguerra, Sergio

    2017-04-01

    This paper presents a novel and simple method of seismic envelope analysis that can be applied at multiple scales, e.g. field, m to km scale and laboratory, mm to cm scale, and utilises the diffusive approximation of the seismic wavefield (Wegler, 2003). Coefficient values for diffusion and attenuation are obtained from seismic coda energies and are used to describe the rate at which seismic energy is scattered and attenuated into the local medium around a receiver. Values are acquired by performing a linear least squares inversion of coda energies calculated in successive time windows along a seismic trace. Acoustic emission data were taken from piezoelectric transducers (PZT) with typical resonance frequency of 1-5MHz glued around rock samples during deformation laboratory experiments carried out using a servo-controlled triaxial testing machine, where a shear/damage zone is generated under compression after the nucleation, growth and coalescence of microcracks. Passive field data were collected from conventional geophones during the 2004-2008 eruption of Mount St. Helens volcano (MSH), USA where a sudden reawakening of the volcanic activity and a new dome growth has occurred. The laboratory study shows a strong correlation between variations of the coefficients over time and the increase of differential stress as the experiment progresses. The field study links structural variations present in the near-surface geology, including those seen in previous geophysical studies of the area, to these same coefficients. Both studies show a correlation between frequency and structural feature size, i.e. landslide slip-planes and microcracks, with higher frequencies being much more sensitive to smaller scale features and vice-versa.

  7. Development and seismic evaluation of the seismic monitoring analysis system for HANARO

    International Nuclear Information System (INIS)

    Ryu, J. S.; Youn, D. B.; Kim, H. G.; Woo, J. S.

    2003-01-01

    Since the start of operation, the seismic monitoring system has been utilized for monitoring an earthquake at the HANARO site. The existing seismic monitoring system consists of field sensors and monitoring panel. The analog-type monitoring system with magnetic tape recorder is out-of-date model. In addition, the disadvantage of the existing system is that it does not include signal-analyzing equipment. Therefore, we have improved the analog seismic monitoring system except the field sensors into a new digital Seismic Monitoring Analysis System(SMAS) that can monitor and analyze earthquake signals. To achieve this objective for HANARO, the digital type hardware of the SMAS has been developed. The seismic monitoring and analysis programs that can provide rapid and precise information for an earthquake were developed. After the installation of the SMAS, we carried out the Site Acceptance Test (SAT) to confirm the functional capability of the newly developed system. The results of the SAT satisfy the requirements of the fabrication technical specifications. In addition, the seismic characteristics and structural integrity of the SMAS were evaluated. The results show that the cabinet of SMAS can withstand the effects of seismic loads and remain functional. This new SMAS is operating in the HANARO instrument room to acquire and analyze the signal of an earthquake

  8. A seismic design of nuclear reactor building structures applying seismic isolation system in a seismicity region-a feasibility case study in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Tetsuo [The University of Tokyo, Tokyo (Japan); Yamamoto, Tomofumi; Sato, Kunihiko [Mitsubishi Heavy Industries, Ltd., Kobe (Japan); Jimbo, Masakazu [Toshiba Corporation, Yokohama (Japan); Imaoka, Tetsuo [Hitachi-GE Nuclear Energy, Ltd., Hitachi (Japan); Umeki, Yoshito [Chubu Electric Power Co. Inc., Nagoya (Japan)

    2014-10-15

    A feasibility study on the seismic design of nuclear reactor buildings with application of a seismic isolation system is introduced. After the Hyogo-ken Nanbu earthquake in Japan of 1995, seismic isolation technologies have been widely employed for commercial buildings. Having become a mature technology, seismic isolation systems can be applied to NPP facilities in areas of high seismicity. Two reactor buildings are discussed, representing the PWR and BWR buildings in Japan, and the application of seismic isolation systems is discussed. The isolation system employing rubber bearings with a lead plug positioned (LRB) is examined. Through a series of seismic response analyses using the so-named standard design earthquake motions covering the design basis earthquake motions obtained for NPP sites in Japan, the responses of the seismic isolated reactor buildings are evaluated. It is revealed that for the building structures examined herein: (1) the responses of both isolated buildings and isolating LRBs fulfill the specified design criteria; (2) the responses obtained for the isolating LRBs first reach the ultimate condition when intensity of motion is 2.0 to 2.5 times as large as that of the design-basis; and (3) the responses of isolated reactor building fall below the range of the prescribed criteria.

  9. Seismic hazard assessment: Issues and alternatives

    Science.gov (United States)

    Wang, Z.

    2011-01-01

    Seismic hazard and risk are two very important concepts in engineering design and other policy considerations. Although seismic hazard and risk have often been used inter-changeably, they are fundamentally different. Furthermore, seismic risk is more important in engineering design and other policy considerations. Seismic hazard assessment is an effort by earth scientists to quantify seismic hazard and its associated uncertainty in time and space and to provide seismic hazard estimates for seismic risk assessment and other applications. Although seismic hazard assessment is more a scientific issue, it deserves special attention because of its significant implication to society. Two approaches, probabilistic seismic hazard analysis (PSHA) and deterministic seismic hazard analysis (DSHA), are commonly used for seismic hazard assessment. Although PSHA has been pro-claimed as the best approach for seismic hazard assessment, it is scientifically flawed (i.e., the physics and mathematics that PSHA is based on are not valid). Use of PSHA could lead to either unsafe or overly conservative engineering design or public policy, each of which has dire consequences to society. On the other hand, DSHA is a viable approach for seismic hazard assessment even though it has been labeled as unreliable. The biggest drawback of DSHA is that the temporal characteristics (i.e., earthquake frequency of occurrence and the associated uncertainty) are often neglected. An alternative, seismic hazard analysis (SHA), utilizes earthquake science and statistics directly and provides a seismic hazard estimate that can be readily used for seismic risk assessment and other applications. ?? 2010 Springer Basel AG.

  10. Seismic and Geodetic Monitoring of the Nicoya, Costa Rica, Seismic Gap

    Science.gov (United States)

    Protti, M.; Gonzalez, V.; Schwartz, S.; Dixon, T.; Kato, T.; Kaneda, Y.; Simila, G.; Sampson, D.

    2007-05-01

    The Nicoya segment of the Middle America Trench has been recognized as a mature seismic gap with potential to generate a large earthquake in the near future (it ruptured with large earthquakes in 1853, 1900 and 1950). Low level of background seismicity and fast crustal deformation of the forearc are indicatives of strong coupling along the plate interface. Given its high seismic potential, the available data and especially the fact that the Nicoya peninsula extends over large part of the rupture area, this gap was selected as one of the two sites for a MARGINS-SEIZE experiment. With the goal of documenting the evolution of loading and stress release along this seismic gap, an international effort involving several institutions from Costa Rica, the United States and Japan is being carried out for over a decade in the region. This effort involves the installation of temporary and permanent seismic and geodetic networks. The seismic network includes short period, broad band and strong motion instruments. The seismic monitoring has provided valuable information on the geometry and characteristics of the plate interface. The geodetic network includes temporary and permanent GPS stations as well as surface and borehole tiltmeters. The geodetic networks have helped quantify the extend and degree of coupling. A continuously recording, three- station GPS network on the Nicoya Peninsula, Costa Rica, recorded what we believe is the first slow slip event observed along the plate interface of the Costa Rica subduction zone. We will present results from these monitoring networks. Collaborative international efforts are focused on expanding these seismic and geodetic networks to provide improved resolution of future creep events, to enhanced understanding of the mechanical behavior of the Nicoya subduction segment of the Middle American Trench and possibly capture the next large earthquake and its potential precursor deformation.

  11. Seismic Structure of Perth Basin (Australia) and surroundings from Passive Seismic Deployments

    Science.gov (United States)

    Issa, N.; Saygin, E.; Lumley, D. E.; Hoskin, T. E.

    2016-12-01

    We image the subsurface structure of Perth Basin, Western Australia and surroundings by using ambient seismic noise data from 14 seismic stations recently deployed by University of Western Australia (UWA) and other available permanent stations from Geoscience Australia seismic network and the Australian Seismometers in Schools program. Each of these 14 UWA seismic stations comprises a broadband sensor and a high fidelity 3-component 10 Hz geophone, recording in tandem at 250 Hz and 1000 Hz. The other stations used in this study are equipped with short period and broadband sensors. In addition, one shallow borehole station is operated with eight 3 component geophones at depths of between 2 and 44 m. The network is deployed to characterize natural seismicity in the basin and to try and identify any microseismic activity across Darling Fault Zone (DFZ), bounding the basin to the east. The DFZ stretches to approximately 1000 km north-south in Western Australia, and is one of the longest fault zones on the earth with a limited number of detected earthquakes. We use seismic noise cross- and auto-correlation methods to map seismic velocity perturbations across the basin and the transition from DFZ to the basin. Retrieved Green's functions are stable and show clear dispersed waveforms. Travel times of the surface wave Green's functions from noise cross-correlations are inverted with a two-step probabilistic framework to map the absolute shear wave velocities as a function of depth. The single station auto-correlations from the seismic noise yields P wave reflectivity under each station, marking the major discontinuities. Resulting images show the shear velocity perturbations across the region. We also quantify the variation of ambient seismic noise at different depths in the near surface using the geophones in the shallow borehole array.

  12. New seismic source `BLASTER` for seismic survey; Hasaiyaku wo shingen to shite mochiita danseiha tansa

    Energy Technology Data Exchange (ETDEWEB)

    Koike, G; Yoshikuni, Y [OYO Corp., Tokyo (Japan)

    1996-10-01

    Built-up weight and vacuole have been conceived as seismic sources without using explosive. There have been problems that they have smaller energy to generate elastic wave than explosive, and that they have inferior working performance. Concrete crushing explosive is tried to use as a new seismic source. It is considered to possess rather large seismic generating energy, and it is easy to handle from the viewpoint of safety. Performance as seismic source and applicability to exploration works of this crushing explosive were compared with four kinds of seismic sources using dynamite, dropping weight, shot-pipe utilizing shot vacuole, and impact by wooden maul. When considered by the velocity amplitude, the seismic generating energy of the crushing explosive of 120 g is about one-fifth of dynamite of 100 g. Elastic wave generated includes less high frequency component than that by dynamite, and similar to that using seismic source without explosive, such as the weight dropping. The maximum seismic receiving distance obtained by the seismic generation was about 100 m. This was effective for the slope survey with the exploration depth between 20 m and 30 m. 1 ref., 9 figs., 2 tabs.

  13. Seismic rupture modelling, strong motion prediction and seismic hazard assessment: fundamental and applied approaches

    International Nuclear Information System (INIS)

    Berge-Thierry, C.

    2007-05-01

    The defence to obtain the 'Habilitation a Diriger des Recherches' is a synthesis of the research work performed since the end of my Ph D. thesis in 1997. This synthesis covers the two years as post doctoral researcher at the Bureau d'Evaluation des Risques Sismiques at the Institut de Protection (BERSSIN), and the seven consecutive years as seismologist and head of the BERSSIN team. This work and the research project are presented in the framework of the seismic risk topic, and particularly with respect to the seismic hazard assessment. Seismic risk combines seismic hazard and vulnerability. Vulnerability combines the strength of building structures and the human and economical consequences in case of structural failure. Seismic hazard is usually defined in terms of plausible seismic motion (soil acceleration or velocity) in a site for a given time period. Either for the regulatory context or the structural specificity (conventional structure or high risk construction), seismic hazard assessment needs: to identify and locate the seismic sources (zones or faults), to characterize their activity, to evaluate the seismic motion to which the structure has to resist (including the site effects). I specialized in the field of numerical strong-motion prediction using high frequency seismic sources modelling and forming part of the IRSN allowed me to rapidly working on the different tasks of seismic hazard assessment. Thanks to the expertise practice and the participation to the regulation evolution (nuclear power plants, conventional and chemical structures), I have been able to work on empirical strong-motion prediction, including site effects. Specific questions related to the interface between seismologists and structural engineers are also presented, especially the quantification of uncertainties. This is part of the research work initiated to improve the selection of the input ground motion in designing or verifying the stability of structures. (author)

  14. Seismic and tsunami safety margin assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    Nuclear Regulation Authority is going to establish new seismic and tsunami safety guidelines to increase the safety of NPPs. The main purpose of this research is testing structures/components important to safety and tsunami resistant structures/components, and evaluating the capacity of them against earthquake and tsunami. Those capacity data will be utilized for the seismic and tsunami back-fit review based on the new seismic and tsunami safety guidelines. The summary of the program in 2012 is as follows. 1. Component seismic capacity test and quantitative seismic capacity evaluation. PWR emergency diesel generator partial-model seismic capacity tests have been conducted and quantitative seismic capacities have been evaluated. 2. Seismic capacity evaluation of switching-station electric equipment. Existing seismic test data investigation, specification survey and seismic response analyses have been conducted. 3. Tsunami capacity evaluation of anti-inundation measure facilities. Tsunami pressure test have been conducted utilizing a small breakwater model and evaluated basic characteristics of tsunami pressure against seawall structure. (author)

  15. Seismic and tsunami safety margin assessment

    International Nuclear Information System (INIS)

    2013-01-01

    Nuclear Regulation Authority is going to establish new seismic and tsunami safety guidelines to increase the safety of NPPs. The main purpose of this research is testing structures/components important to safety and tsunami resistant structures/components, and evaluating the capacity of them against earthquake and tsunami. Those capacity data will be utilized for the seismic and tsunami back-fit review based on the new seismic and tsunami safety guidelines. The summary of the program in 2012 is as follows. 1. Component seismic capacity test and quantitative seismic capacity evaluation. PWR emergency diesel generator partial-model seismic capacity tests have been conducted and quantitative seismic capacities have been evaluated. 2. Seismic capacity evaluation of switching-station electric equipment. Existing seismic test data investigation, specification survey and seismic response analyses have been conducted. 3. Tsunami capacity evaluation of anti-inundation measure facilities. Tsunami pressure test have been conducted utilizing a small breakwater model and evaluated basic characteristics of tsunami pressure against seawall structure. (author)

  16. Seismic Consequence Abstraction

    International Nuclear Information System (INIS)

    Gross, M.

    2004-01-01

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])

  17. Seismic Consequence Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    M. Gross

    2004-10-25

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  18. Co-seismic slip, post-seismic slip, and largest aftershock associated with the 1994 Sanriku-haruka-oki, Japan, earthquake

    Science.gov (United States)

    Yagi, Yuji; Kikuchi, Masayuki; Nishimura, Takuya

    2003-11-01

    We analyzed continuous GPS data to investigate the spatio-temporal distribution of co-seismic slip, post-seismic slip, and largest aftershock associated with the 1994 Sanriku-haruka-oki, Japan, earthquake (Mw = 7.7). To get better resolution for co-seismic and post-seismic slip distribution, we imposed a weak constraint as a priori information of the co-seismic slip determined by seismic wave analyses. We found that the post-seismic slip during 100 days following the main-shock amount to as much moment release as the main-shock, and that the sites of co-seismic slip and post-seismic slip are partitioning on a plate boundary region in complimentary fashion. The major post-seismic slip was triggered by the mainshock in western side of the co-seismic slip, and the extent of the post-seismic slip is almost unchanged with time. It rapidly developed a shear stress concentration ahead of the slip area, and triggered the largest aftershock.

  19. A novel tree-based algorithm to discover seismic patterns in earthquake catalogs

    Science.gov (United States)

    Florido, E.; Asencio-Cortés, G.; Aznarte, J. L.; Rubio-Escudero, C.; Martínez-Álvarez, F.

    2018-06-01

    A novel methodology is introduced in this research study to detect seismic precursors. Based on an existing approach, the new methodology searches for patterns in the historical data. Such patterns may contain statistical or soil dynamics information. It improves the original version in several aspects. First, new seismicity indicators have been used to characterize earthquakes. Second, a machine learning clustering algorithm has been applied in a very flexible way, thus allowing the discovery of new data groupings. Third, a novel search strategy is proposed in order to obtain non-overlapped patterns. And, fourth, arbitrary lengths of patterns are searched for, thus discovering long and short-term behaviors that may influence in the occurrence of medium-large earthquakes. The methodology has been applied to seven different datasets, from three different regions, namely the Iberian Peninsula, Chile and Japan. Reported results show a remarkable improvement with respect to the former version, in terms of all evaluated quality measures. In particular, the number of false positives has decreased and the positive predictive values increased, both of them in a very remarkable manner.

  20. Seismic Safety Program: Ground motion and structural response

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

    In 1964, John A. Blume & Associates Research Division (Blume) began a broad-range structural response program to assist the Nevada Operations Office of the US Atomic Energy Commission (AEC) in ensuring the continued safe conduct of underground nuclear detonation testing at the Nevada Test Site (NTS) and elsewhere. Blume`s long experience in earthquake engineering provided a general basis for the program, but much more specialized knowledge was required for the AEC`s purposes. Over the next 24 years Blume conducted a major research program to provide essential understanding of the detailed nature of the response of structures to dynamic loads such as those imposed by seismic wave propagation. The program`s results have been embodied in a prediction technology which has served to provide reliable advanced knowledge of the probable effects of seismic ground motion on all kinds of structures, for use in earthquake engineering and in building codes as well as for the continuing needs of the US Department of Energy`s Nevada Operations Office (DOE/NV). This report is primarily an accounting of the Blume work, beginning with the setting in 1964 and the perception of the program needs as envisioned by Dr. John A. Blume. Subsequent chapters describe the structural response program in detail and the structural prediction procedures which resulted; the intensive data acquisition program which, as is discussed at some length, relied heavily on the contributions of other consultant-contractors in the DOE/NV Seismic Safety Support Program; laboratory and field studies to provide data on building elements and structures subjected to dynamic loads from sources ranging from testing machines to earthquakes; structural response activities undertaken for testing at the NTS and for off-NTS underground nuclear detonations; and concluding with an account of corollary studies including effects of natural forces and of related studies on building response.

  1. Risk based seismic design criteria

    International Nuclear Information System (INIS)

    Kennedy, R.P.

    1999-01-01

    In order to develop a risk based seismic design criteria the following four issues must be addressed: (1) What target annual probability of seismic induced unacceptable performance is acceptable? (2) What minimum seismic margin is acceptable? (3) Given the decisions made under Issues 1 and 2, at what annual frequency of exceedance should the safe-shutdown-earthquake (SSE) ground motion be defined? (4) What seismic design criteria should be established to reasonably achieve the seismic margin defined under Issue 2? The first issue is purely a policy decision and is not addressed in this paper. Each of the other three issues are addressed. Issues 2 and 3 are integrally tied together so that a very large number of possible combinations of responses to these two issues can be used to achieve the target goal defined under Issue 1. Section 2 lays out a combined approach to these two issues and presents three potentially attractive combined resolutions of these two issues which reasonably achieves the target goal. The remainder of the paper discusses an approach which can be used to develop seismic design criteria aimed at achieving the desired seismic margin defined in resolution of Issue 2. Suggestions for revising existing seismic design criteria to more consistently achieve the desired seismic margin are presented. (orig.)

  2. Machine rates for selected forest harvesting machines

    Science.gov (United States)

    R.W. Brinker; J. Kinard; Robert Rummer; B. Lanford

    2002-01-01

    Very little new literature has been published on the subject of machine rates and machine cost analysis since 1989 when the Alabama Agricultural Experiment Station Circular 296, Machine Rates for Selected Forest Harvesting Machines, was originally published. Many machines discussed in the original publication have undergone substantial changes in various aspects, not...

  3. Enhancement of seismic resistance of buildings

    Directory of Open Access Journals (Sweden)

    Claudiu-Sorin Dragomir

    2014-03-01

    Full Text Available The objectives of the paper are both seismic instrumentation for damage assessment and enhancing of seismic resistance of buildings. In according with seismic design codes in force the buildings are designed to resist at seismic actions. Due to the time evolution of these design provisions, there are buildings that were designed decades ago, under the less stringent provisions. The conceptual conformation is nowadays provided in all Codes of seismic design. According to the Code of seismic design P100-1:2006 the asymmetric structures do not have an appropriate seismic configuration; they have disadvantageous distribution of volumes, mass and stiffness. Using results of temporary seismic instrumentation the safety condition of the building may be assessed in different phases of work. Based on this method, the strengthening solutions may be identified and the need of seismic joints may be emphasised. All the aforementioned ideas are illustrated through a case study. Therefore it will be analysed the dynamic parameter evolution of an educational building obtained in different periods. Also, structural intervention scenarios to enhance seismic resistance will be presented.

  4. Seismic risk map for Southeastern Brazil

    International Nuclear Information System (INIS)

    Mioto, J.A.

    1984-01-01

    During the last few years, some studies regarding seismic risk were prepared for three regions of Brazil. They were carried on account of two basic interests: first, toward the seismic history and recurrence of Brazilian seismic events; second, in a way as to provide seismic parameters for the design and construction of hydro and nuclear power plants. The first seismic risk map prepared for the southeastern region was elaborated in 1979 by 6he Universidade de Brasilia (UnB-Brasilia Seismological Station). In 1981 another seismic risk map was completed on the basis of seismotectonic studies carried out for the design and construction of the Nuclear power plants of Itaorna Beach (Angra dos Reis, Rio de Janeiro) by IPT (Mining and Applied Geology Division). In Brazil, until 1984, seismic studies concerning hydro and nuclear power plants and other civil construction of larger size did not take into account the seismic events from the point of view of probabilities of seismic recurrences. Such analysis in design is more important than the choice of a level of intensity or magnitude, or adoption of a seismicity level ased on deterministic methods. In this way, some considerations were made, concerning the use of seisms in Brazilian designs of hydro and nuclear power plants, as far as seismic analysis is concerned, recently altered over the current seismic risk panorama. (D.J.M.) [pt

  5. Seismic retrofitting of Apsara reactor building

    International Nuclear Information System (INIS)

    Reddy, G.R.; Parulekar, Y.M.; Sharma, A.; Rao, K.N.; Narasimhan, Rajiv; Srinivas, K.; Basha, S.M.; Thomas, V.S.; Soma Kumar, K.

    2006-01-01

    Seismic analysis of Apsara Reactor building was carried out and was found not meeting the current seismic requirements. Due to the building not qualifying for seismic loads, a retrofit scheme using elasto-plastic dampers is proposed. Following activities have been performed in this direction: Carried out detailed seismic analysis of Apsara reactor building structure incorporating proposed seismic retrofit. Demonstrating the capability of the retrofitted structure to with stand the earth quake level for Trombay site as per the current standards by analysis and by model studies. Implementation of seismic retrofit program. This paper presents the details of above aspects related to Seismic analysis and retrofitting of Apsara reactor building. (author)

  6. Seismic fragility analyses

    International Nuclear Information System (INIS)

    Kostov, Marin

    2000-01-01

    In the last two decades there is increasing number of probabilistic seismic risk assessments performed. The basic ideas of the procedure for performing a Probabilistic Safety Analysis (PSA) of critical structures (NUREG/CR-2300, 1983) could be used also for normal industrial and residential buildings, dams or other structures. The general formulation of the risk assessment procedure applied in this investigation is presented in Franzini, et al., 1984. The probability of failure of a structure for an expected lifetime (for example 50 years) can be obtained from the annual frequency of failure, β E determined by the relation: β E ∫[d[β(x)]/dx]P(flx)dx. β(x) is the annual frequency of exceedance of load level x (for example, the variable x may be peak ground acceleration), P(fI x) is the conditional probability of structure failure at a given seismic load level x. The problem leads to the assessment of the seismic hazard β(x) and the fragility P(fl x). The seismic hazard curves are obtained by the probabilistic seismic hazard analysis. The fragility curves are obtained after the response of the structure is defined as probabilistic and its capacity and the associated uncertainties are assessed. Finally the fragility curves are combined with the seismic loading to estimate the frequency of failure for each critical scenario. The frequency of failure due to seismic event is presented by the scenario with the highest frequency. The tools usually applied for probabilistic safety analyses of critical structures could relatively easily be adopted to ordinary structures. The key problems are the seismic hazard definitions and the fragility analyses. The fragility could be derived either based on scaling procedures or on the base of generation. Both approaches have been presented in the paper. After the seismic risk (in terms of failure probability) is assessed there are several approaches for risk reduction. Generally the methods could be classified in two groups. The

  7. Detection capability of the IMS seismic network based on ambient seismic noise measurements

    Science.gov (United States)

    Gaebler, Peter J.; Ceranna, Lars

    2016-04-01

    All nuclear explosions - on the Earth's surface, underground, underwater or in the atmosphere - are banned by the Comprehensive Nuclear-Test-Ban Treaty (CTBT). As part of this treaty, a verification regime was put into place to detect, locate and characterize nuclear explosion testings at any time, by anyone and everywhere on the Earth. The International Monitoring System (IMS) plays a key role in the verification regime of the CTBT. Out of the different monitoring techniques used in the IMS, the seismic waveform approach is the most effective technology for monitoring nuclear underground testing and to identify and characterize potential nuclear events. This study introduces a method of seismic threshold monitoring to assess an upper magnitude limit of a potential seismic event in a certain given geographical region. The method is based on ambient seismic background noise measurements at the individual IMS seismic stations as well as on global distance correction terms for body wave magnitudes, which are calculated using the seismic reflectivity method. From our investigations we conclude that a global detection threshold of around mb 4.0 can be achieved using only stations from the primary seismic network, a clear latitudinal dependence for the detection threshold can be observed between northern and southern hemisphere. Including the seismic stations being part of the auxiliary seismic IMS network results in a slight improvement of global detection capability. However, including wave arrivals from distances greater than 120 degrees, mainly PKP-wave arrivals, leads to a significant improvement in average global detection capability. In special this leads to an improvement of the detection threshold on the southern hemisphere. We further investigate the dependence of the detection capability on spatial (latitude and longitude) and temporal (time) parameters, as well as on parameters such as source type and percentage of operational IMS stations.

  8. Georgia-Armenia Transboarder seismicity studies

    Science.gov (United States)

    Godoladze, T.; Tvaradze, N.; Javakishvili, Z.; Elashvili, M.; Durgaryan, R.; Arakelyan, A.; Gevorgyan, M.

    2012-12-01

    In the presented study we performed Comprehensive seismic analyses for the Armenian-Georgian transboarder active seismic fault starting on Armenian territory, cutting the state boarder and having possibly northern termination on Adjara-Triealeti frontal structure in Georgia. In the scope of International projects: ISTC A-1418 "Open network of scientific Centers for mitigation risk of natural hazards in the Southern Caucasus and Central Asia" and NATO SfP- 983284 Project "Caucasus Seismic Emergency Response" in Akhalkalaki (Georgia) seismic center, Regional Summer school trainings and intensive filed investigations were conducted. Main goal was multidisciplinary study of the Javakheti fault structure and better understanding seismicity of the area. Young scientists from Turkey, Armenia, Azerbaijan and Georgia were participated in the deployment of temporal seismic network in order to monitor seisimity on the Javakheti highland and particularly delineate fault scarf and identify active seismic structures. In the scope of international collaboration the common seismic database has been created in the southern Caucasus and collected data from the field works is available now online. Javakheti highland, which is located in the central part of the Caucasus, belongs to the structure of the lesser Caucasus and represents a history of neotectonic volcanism existed in the area. Jasvakheti highland is seismicalu active region devastating from several severe earthquakes(1088, 1283, 1899…). Hypocenters located during analogue network were highly scattered and did not describe real pattern of seismicity of the highland. We relocated hypocenters of the region and improved local velocity model. The hypocenters derived from recently deployed local seismic network in the Javakheti highland, clearly identified seismically active structures. Fault plane solutions of analogue data of the Soviet times have been carefully analyzed and examined. Moment tensor inversion were preformed

  9. SEISMIC ANALYSIS FOR PRECLOSURE SAFETY

    Energy Technology Data Exchange (ETDEWEB)

    E.N. Lindner

    2004-12-03

    The purpose of this seismic preclosure safety analysis is to identify the potential seismically-initiated event sequences associated with preclosure operations of the repository at Yucca Mountain and assign appropriate design bases to provide assurance of achieving the performance objectives specified in the Code of Federal Regulations (CFR) 10 CFR Part 63 for radiological consequences. This seismic preclosure safety analysis is performed in support of the License Application for the Yucca Mountain Project. In more detail, this analysis identifies the systems, structures, and components (SSCs) that are subject to seismic design bases. This analysis assigns one of two design basis ground motion (DBGM) levels, DBGM-1 or DBGM-2, to SSCs important to safety (ITS) that are credited in the prevention or mitigation of seismically-initiated event sequences. An application of seismic margins approach is also demonstrated for SSCs assigned to DBGM-2 by showing a high confidence of a low probability of failure at a higher ground acceleration value, termed a beyond-design basis ground motion (BDBGM) level. The objective of this analysis is to meet the performance requirements of 10 CFR 63.111(a) and 10 CFR 63.111(b) for offsite and worker doses. The results of this calculation are used as inputs to the following: (1) A classification analysis of SSCs ITS by identifying potential seismically-initiated failures (loss of safety function) that could lead to undesired consequences; (2) An assignment of either DBGM-1 or DBGM-2 to each SSC ITS credited in the prevention or mitigation of a seismically-initiated event sequence; and (3) A nuclear safety design basis report that will state the seismic design requirements that are credited in this analysis. The present analysis reflects the design information available as of October 2004 and is considered preliminary. The evolving design of the repository will be re-evaluated periodically to ensure that seismic hazards are properly

  10. SEISMIC ANALYSIS FOR PRECLOSURE SAFETY

    International Nuclear Information System (INIS)

    E.N. Lindner

    2004-01-01

    The purpose of this seismic preclosure safety analysis is to identify the potential seismically-initiated event sequences associated with preclosure operations of the repository at Yucca Mountain and assign appropriate design bases to provide assurance of achieving the performance objectives specified in the Code of Federal Regulations (CFR) 10 CFR Part 63 for radiological consequences. This seismic preclosure safety analysis is performed in support of the License Application for the Yucca Mountain Project. In more detail, this analysis identifies the systems, structures, and components (SSCs) that are subject to seismic design bases. This analysis assigns one of two design basis ground motion (DBGM) levels, DBGM-1 or DBGM-2, to SSCs important to safety (ITS) that are credited in the prevention or mitigation of seismically-initiated event sequences. An application of seismic margins approach is also demonstrated for SSCs assigned to DBGM-2 by showing a high confidence of a low probability of failure at a higher ground acceleration value, termed a beyond-design basis ground motion (BDBGM) level. The objective of this analysis is to meet the performance requirements of 10 CFR 63.111(a) and 10 CFR 63.111(b) for offsite and worker doses. The results of this calculation are used as inputs to the following: (1) A classification analysis of SSCs ITS by identifying potential seismically-initiated failures (loss of safety function) that could lead to undesired consequences; (2) An assignment of either DBGM-1 or DBGM-2 to each SSC ITS credited in the prevention or mitigation of a seismically-initiated event sequence; and (3) A nuclear safety design basis report that will state the seismic design requirements that are credited in this analysis. The present analysis reflects the design information available as of October 2004 and is considered preliminary. The evolving design of the repository will be re-evaluated periodically to ensure that seismic hazards are properly

  11. A SEISMIC DESIGN OF NUCLEAR REACTOR BUILDING STRUCTURES APPLYING SEISMIC ISOLATION SYSTEM IN A HIGH SEISMICITY REGION –A FEASIBILITY CASE STUDY IN JAPAN-

    Directory of Open Access Journals (Sweden)

    TETSUO KUBO

    2014-10-01

    Full Text Available A feasibility study on the seismic design of nuclear reactor buildings with application of a seismic isolation system is introduced. After the Hyogo-ken Nanbu earthquake in Japan of 1995, seismic isolation technologies have been widely employed for commercial buildings. Having become a mature technology, seismic isolation systems can be applied to NPP facilities in areas of high seismicity. Two reactor buildings are discussed, representing the PWR and BWR buildings in Japan, and the application of seismic isolation systems is discussed. The isolation system employing rubber bearings with a lead plug positioned (LRB is examined. Through a series of seismic response analyses using the so-named standard design earthquake motions covering the design basis earthquake motions obtained for NPP sites in Japan, the responses of the seismic isolated reactor buildings are evaluated. It is revealed that for the building structures examined herein: (1 the responses of both isolated buildings and isolating LRBs fulfill the specified design criteria; (2 the responses obtained for the isolating LRBs first reach the ultimate condition when intensity of motion is 2.0 to 2.5 times as large as that of the design-basis; and (3 the responses of isolated reactor building fall below the range of the prescribed criteria.

  12. Seismic fragility capacity of equipment

    International Nuclear Information System (INIS)

    Iijima, Toru; Abe, Hiroshi; Suzuki, Kenichi

    2006-01-01

    Seismic probabilistic safety assessment (PSA) is an available method to evaluate residual risks of nuclear plants that are designed on definitive seismic conditions. From our preliminary seismic PSA analysis, horizontal shaft pumps are important components that have significant influences on the core damage frequency (CDF). An actual horizontal shaft pump and some kinds of elements were tested to evaluate realistic fragility capacities. Our test results showed that the realistic fragility capacity of horizontal shaft pump would be at least four times as high as a current value, 1.6 x 9.8 m/s 2 , used for our seismic PSA. We are going to incorporate the fragility capacity data that were obtained from those tests into our seismic PSA analysis, and we expect that the reliability of seismic PSA should increase. (author)

  13. Two applications of time reversal mirrors: Seismic radio and seismic radar

    KAUST Repository

    Hanafy, Sherif M.

    2011-07-08

    Two seismic applications of time reversal mirrors (TRMs) are introduced and tested with field experiments. The first one is sending, receiving, and decoding coded messages similar to a radio except seismic waves are used. The second one is, similar to radar surveillance, detecting and tracking a moving object(s) in a remote area, including the determination of the objects speed of movement. Both applications require the prior recording of calibrationGreen’s functions in the area of interest. This reference Green’s function will be used as a codebook to decrypt the coded message in the first application and as a moving sensor for the second application. Field tests show that seismicradar can detect the moving coordinates ( x(t), y(t), z(t)) of a person running through a calibration site. This information also allows for a calculation of his velocity as a function of location. Results with the seismic radio are successful in seismically detecting and decoding coded pulses produced by a hammer. Both seismic radio and radar are highly robust to signals in high noise environments due to the super-stacking property of TRMs.

  14. Two applications of time reversal mirrors: Seismic radio and seismic radar

    KAUST Repository

    Hanafy, Sherif M.; Schuster, Gerard T.

    2011-01-01

    Two seismic applications of time reversal mirrors (TRMs) are introduced and tested with field experiments. The first one is sending, receiving, and decoding coded messages similar to a radio except seismic waves are used. The second one is, similar

  15. 3D Modelling of Seismically Active Parts of Underground Faults via Seismic Data Mining

    Science.gov (United States)

    Frantzeskakis, Theofanis; Konstantaras, Anthony

    2015-04-01

    During the last few years rapid steps have been taken towards drilling for oil in the western Mediterranean sea. Since most of the countries in the region benefit mainly from tourism and considering that the Mediterranean is a closed sea only replenishing its water once every ninety years careful measures are being taken to ensure safe drilling. In that concept this research work attempts to derive a three dimensional model of the seismically active parts of the underlying underground faults in areas of petroleum interest. For that purpose seismic spatio-temporal clustering has been applied to seismic data to identify potential distinct seismic regions in the area of interest. Results have been coalesced with two dimensional maps of underground faults from past surveys and seismic epicentres, having followed careful reallocation processing, have been used to provide information regarding the vertical extent of multiple underground faults in the region of interest. The end product is a three dimensional map of the possible underground location and extent of the seismically active parts of underground faults. Indexing terms: underground faults modelling, seismic data mining, 3D visualisation, active seismic source mapping, seismic hazard evaluation, dangerous phenomena modelling Acknowledgment This research work is supported by the ESPA Operational Programme, Education and Life Long Learning, Students Practical Placement Initiative. References [1] Alves, T.M., Kokinou, E. and Zodiatis, G.: 'A three-step model to assess shoreline and offshore susceptibility to oil spills: The South Aegean (Crete) as an analogue for confined marine basins', Marine Pollution Bulletin, In Press, 2014 [2] Ciappa, A., Costabile, S.: 'Oil spill hazard assessment using a reverse trajectory method for the Egadi marine protected area (Central Mediterranean Sea)', Marine Pollution Bulletin, vol. 84 (1-2), pp. 44-55, 2014 [3] Ganas, A., Karastathis, V., Moshou, A., Valkaniotis, S., Mouzakiotis

  16. Effects of applying three-dimensional seismic isolation system on the seismic design of FBR

    International Nuclear Information System (INIS)

    Hirata, Kazuta; Yabana, Shuichi; Kanazawa, Kenji; Matsuda, Akihiro

    1997-01-01

    In this study conceptional three-dimensional seismic isolation system for fast breeder reactor (FBR) is proposed. Effects of applying three-dimensional seismic isolation system on the seismic design for the FBR equipment are evaluated quantitatively. From the evaluation, it is concluded following effects are expected by applying the three-dimensional seismic isolation system to the FBR and the effects are evaluated quantitatively. (1) Reduction of membrane thickness of the reactor vessel (2) Suppression of uplift of fuels by reducing vertical seismic response of the core (3) Reduction of the supports for the piping system (4) Three-dimensional base isolation system for the whole reactor building is advantageous to the combined isolation system of horizontal base isolation for the reactor building and vertical isolation for the equipment. (author)

  17. [A new machinability test machine and the machinability of composite resins for core built-up].

    Science.gov (United States)

    Iwasaki, N

    2001-06-01

    A new machinability test machine especially for dental materials was contrived. The purpose of this study was to evaluate the effects of grinding conditions on machinability of core built-up resins using this machine, and to confirm the relationship between machinability and other properties of composite resins. The experimental machinability test machine consisted of a dental air-turbine handpiece, a control weight unit, a driving unit of the stage fixing the test specimen, and so on. The machinability was evaluated as the change in volume after grinding using a diamond point. Five kinds of core built-up resins and human teeth were used in this study. The machinabilities of these composite resins increased with an increasing load during grinding, and decreased with repeated grinding. There was no obvious correlation between the machinability and Vickers' hardness; however, a negative correlation was observed between machinability and scratch width.

  18. PARAMETERS OF KAMCHATKA SEISMICITY IN 2008

    Directory of Open Access Journals (Sweden)

    Vadim A. Saltykov

    2010-01-01

    Full Text Available The paper describes seismicity of Kamchatka for the period of 2008 and presents 2D distribution of background seismicity parameters calculated from data published in the Regional Catalogue of Kamchatka Earthquakes. Parameters under study are total released seismic energy, seismic activity A10, slope of recurrence graph γ, parameters of RTL, ΔS and Z-function methods, and clustering of earthquakes. Estimations of seismicity are obtained for a region bordered by latitude 50.5–56.5N, longitude 156E–167E, with depths to 300 km. Earthquakes of energy classes not less than 8.5 as per the Fedotov’s classification are considered. The total seismic energy released in 2008 is estimated. According to a function of annual seismic energy distribution, an amount of seismic energy released in 2008 was close to the median level (Fig. 1. Over 2/3 of the total amount of seismic energy released in 2008 resulted from three largest earthquakes (МW ≥ 5.9. About 5 percent of the total number of seismic events are comprised of grouped earthquakes, i.e. aftershocks and swarms. A schematic map of the largest earthquakes (МW ≥ 5.9 and grouped seismic events which occurred in 2008 is given in Fig. 2; their parameters are listed in Table 1. Grouped earthquakes are excluded from the catalogue. A map showing epicenters of independent earthquakes is given in Fig. 3. The slope of recurrence graph γ and seismic activity A10 is based on the Gutenberg-Richter law stating the fundamental property of seismic process. The recurrence graph slope is calculated from continuous exponential distribution of earthquakes by energy classes. Using γ is conditioned by observations that in some cases the slope of the recurrence graph decreases prior to a large earthquake. Activity A10 is calculated from the number of earthquakes N and recurrence graph slope γ. Average slopes of recurrence graph γ and seismic activity A10 for the area under study in 2008 are calculated; our

  19. Moment magnitude determination of local seismic events recorded at selected Polish seismic stations

    Science.gov (United States)

    Wiejacz, Paweł; Wiszniowski, Jan

    2006-03-01

    The paper presents the method of local magnitude determination used at Polish seismic stations to report events originating in one of the four regions of induced seismicity in Poland or its immediate vicinity. The method is based on recalculation of the seismic moment into magnitude, whereas the seismic moment is obtained from spectral analysis. The method has been introduced at Polish seismic stations in the late 1990s but as of yet had not been described in full because magnitude discrepancies have been found between the results of the individual stations. The authors have performed statistics of these differences, provide their explanation and calculate station corrections for each station and each event source region. The limitations of the method are also discussed. The method is found to be a good and reliable method of local magnitude determination provided the limitations are observed and station correction applied.

  20. Use of the t-distribution to construct seismic hazard curves for seismic probabilistic safety assessments

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Eric [KEPCO International Nuclear Graduate School, Dept. of Nuclear Power Plant Engineering, Ulsan (Korea, Republic of)

    2017-03-15

    Seismic probabilistic safety assessments are used to help understand the impact potential seismic events can have on the operation of a nuclear power plant. An important component to seismic probabilistic safety assessment is the seismic hazard curve which shows the frequency of seismic events. However, these hazard curves are estimated assuming a normal distribution of the seismic events. This may not be a strong assumption given the number of recorded events at each source-to-site distance. The use of a normal distribution makes the calculations significantly easier but may underestimate or overestimate the more rare events, which is of concern to nuclear power plants. This paper shows a preliminary exploration into the effect of using a distribution that perhaps more represents the distribution of events, such as the t-distribution to describe data. The integration of a probability distribution with potentially larger tails basically pushes the hazard curves outward, suggesting a different range of frequencies for use in seismic probabilistic safety assessments. Therefore the use of a more realistic distribution results in an increase in the frequency calculations suggesting rare events are less rare than thought in terms of seismic probabilistic safety assessment. However, the opposite was observed with the ground motion prediction equation considered.

  1. Use of the t-distribution to construct seismic hazard curves for seismic probabilistic safety assessments

    International Nuclear Information System (INIS)

    Yee, Eric

    2017-01-01

    Seismic probabilistic safety assessments are used to help understand the impact potential seismic events can have on the operation of a nuclear power plant. An important component to seismic probabilistic safety assessment is the seismic hazard curve which shows the frequency of seismic events. However, these hazard curves are estimated assuming a normal distribution of the seismic events. This may not be a strong assumption given the number of recorded events at each source-to-site distance. The use of a normal distribution makes the calculations significantly easier but may underestimate or overestimate the more rare events, which is of concern to nuclear power plants. This paper shows a preliminary exploration into the effect of using a distribution that perhaps more represents the distribution of events, such as the t-distribution to describe data. The integration of a probability distribution with potentially larger tails basically pushes the hazard curves outward, suggesting a different range of frequencies for use in seismic probabilistic safety assessments. Therefore the use of a more realistic distribution results in an increase in the frequency calculations suggesting rare events are less rare than thought in terms of seismic probabilistic safety assessment. However, the opposite was observed with the ground motion prediction equation considered

  2. Seismic hazard assessment of Iran

    Directory of Open Access Journals (Sweden)

    M. Ghafory-Ashtiany

    1999-06-01

    Full Text Available The development of the new seismic hazard map of Iran is based on probabilistic seismic hazard computation using the historical earthquakes data, geology, tectonics, fault activity and seismic source models in Iran. These maps have been prepared to indicate the earthquake hazard of Iran in the form of iso-acceleration contour lines, and seismic hazard zoning, by using current probabilistic procedures. They display the probabilistic estimates of Peak Ground Acceleration (PGA for the return periods of 75 and 475 years. The maps have been divided into intervals of 0.25 degrees in both latitudinal and longitudinal directions to calculate the peak ground acceleration values at each grid point and draw the seismic hazard curves. The results presented in this study will provide the basis for the preparation of seismic risk maps, the estimation of earthquake insurance premiums, and the preliminary site evaluation of critical facilities.

  3. Seismic qualification of multiple interconnected safety-related cabinets in a high seismic zone

    International Nuclear Information System (INIS)

    Khan, M.R.; Chen, W.H.W.; Wang, T.Y.

    1993-01-01

    Certain safety-related multiple, interconnected electrical cabinets and the devices contained therein are required to perform their intended safety functions during and after a design basis seismic event. In general, seismic testing is performed to ensure the structural integrity of the cabinets and the functionality of their associated devices. Constrained by the shake table capacity, seismic testing is usually performed only for a limited number of interconnected cabinets. Also, original shake table tests performed usually did not provide detailed response information at various locations inside the cabinets. For operational and maintenance purposes, doors and panels of some cabinets may need to be opened while the adjacent cabinets are required to remain functional. In addition, in-cabinet response spectra need to be generated for the seismic qualification of new devices and the replacement parts. Consequently, seismic analysis of safety-related multiple, interconnected cabinets is frequently required for configurations which are different from the original tested conditions. This paper presents results of seismic tests of three interconnected safety-related cabinets and finite element analyses performed to compare the analytical results with those obtained from the cabinet seismic tests. Parametric analyses are performed to determine how many panels and doors can be opened while the adjacent cabinets still remain functional. The study indicates that for cabinets located in a high seismic zone, the critical damping of the cabinet is significantly higher than 5% to 7% typically used in qualifying electrical equipment. For devices mounted on the cabinet doors to performed their intended safety function, it requires stiffening of doors and that these doors be properly bolted to the cabinet frame. It also shows that even though doors and panels bolted to the cabinet frame are the primary seismic resistant element of the cabinet, opening of a limited number of them

  4. Development of a Real-Time GPS/Seismic Displacement Meter: Seismic Component and Communications

    Science.gov (United States)

    Vernon, F.; Bock, Y.

    2002-12-01

    In two abstracts, we report on an ongoing effort to develop an Integrated Real-Time GPS/Seismic System for Orange and Western Riverside Counties, California, spanning three major strike-slip faults in southern California (San Andreas, San Jacinto, and Elsinore) and significant populations and civilian infrastructure. The system relying on existing GPS and seismic networks will collect and analyze GPS and seismic data for the purpose of estimating and disseminating real-time positions and total ground displacements (dynamic, as well as static) covering all phases of the seismic cycle, from fractions of seconds to years. Besides its intrinsic scientific use as a real-time displacement meter (transducer), the GPS/Seismic System will be a powerful tool for local and state decision makers for risk mitigation, disaster management, and structural monitoring (dams, bridges, and buildings). Furthermore, the GPS/Seismic System will become an integral part of California's spatial referencing and positioning infrastructure, which is complicated by tectonic motion, seismic displacements, and land subsidence. This development is taking place under the umbrella of the California Spatial Reference Center, in partnership with local (The Counties, Riverside County Flood and Water Conservation District, Southern California Metropolitan Water District), state (Caltrans), and Federal agencies (NGS, NASA, USGS), the geophysics community (SCEC2/SCIGN), and the private sector (RBF Consulting). The project is leveraging considerable funding, resources, and research and development from SCIGN, CSRC and two NSF-funded IT projects at UCSD and SDSU: RoadNet (Real-Time Observatories, Applications and Data Management Network) and the High Performance Wireless Research and Education Network (HPWREN). These two projects are funded to develop both the wireless networks and the integrated, seamless, and transparent information management system that will deliver seismic, geodetic, oceanographic

  5. Seismic risk assessment of a BWR

    International Nuclear Information System (INIS)

    Wells, J.E.; Bernreuter, D.L.; Chen, J.C.; Lappa, D.A.; Chuang, T.Y.; Murray, R.C.; Johnson, J.J.

    1987-01-01

    The simplified seismic risk methodology developed in the USNRC Seismic Safety Margins Research Program (SSMRP) was demonstrated by its application to the Zion nuclear power plant (PWR). The simplified seismic risk methodology was developed to reduce the costs associated with a seismic risk analysis while providing adequate results. A detailed model of Zion, including systems analysis models (initiating events, event trees, and fault trees), SSI and structure models, and piping models, was developed and used in assessing the seismic risk of the Zion nuclear power plant (FSAR). The simplified seismic risk methodology was applied to the LaSalle County Station nuclear power plant, a BWR; to further demonstrate its applicability, and if possible, to provide a basis for comparing the seismic risk from PWRs and BWRs. (orig./HP)

  6. Seismic isolation in New Zealand

    International Nuclear Information System (INIS)

    Skinner, R.I.; Robinson, W.H.; McVerry, G.H.

    1989-01-01

    Bridges, buildings, and industrial equipment can be given increased protection from earthquake damage by limiting the earthquake attack through seismic isolation. A broad summary of the seismic responses of base-isolated structures is of considerable assistance for their preliminary design. Seismic isolation as already used in New Zealand consists of a flexible base or support combined with some form of energy-dissipating device, usually involving the hysteretic working of steel or lead. This paper presents examples of the New Zealand experience, where seismic isolation has been used for 42 bridges, 3 buildings, a tall chimney, and high-voltage capacitor banks. Additional seismic response factors, which may be important for nuclear power plants, are also discussed briefly

  7. Demonstration of NonLinear Seismic Soil Structure Interaction and Applicability to New System Fragility Seismic Curves

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Science and Technology

    2014-09-01

    Risk calculations should focus on providing best estimate results, and associated insights, for evaluation and decision-making. Specifically, seismic probabilistic risk assessments (SPRAs) are intended to provide best estimates of the various combinations of structural and equipment failures that can lead to a seismic induced core damage event. However, in general this approach has been conservative, and potentially masks other important events (for instance, it was not the seismic motions that caused the Fukushima core melt events, but the tsunami ingress into the facility). SPRAs are performed by convolving the seismic hazard (the frequency of certain magnitude events) with the seismic fragility (the conditional probability of failure of a structure, system, or component given the occurrence of earthquake ground motion). In this calculation, there are three main pieces to seismic risk quantification, 1) seismic hazard and nuclear power plants (NPPs) response to the hazard, fragility or capacity of structures, systems and components (SSC), and systems analysis. Figure 1 provides a high level overview of the risk quantification process. The focus of this research is on understanding and removing conservatism (when possible) in the quantification of seismic risk at NPPs.

  8. Comparison between seismic and domestic risk in moderate seismic hazard prone region: the Grenoble City (France test site

    Directory of Open Access Journals (Sweden)

    F. Dunand

    2012-02-01

    Full Text Available France has a moderate level of seismic activity, characterized by diffuse seismicity, sometimes experiencing earthquakes of a magnitude of more than 5 in the most active zones. In this seismicity context, Grenoble is a city of major economic and social importance. However, earthquakes being rare, public authorities and the decision makers are only vaguely committed to reducing seismic risk: return periods are long and local policy makers do not have much information available. Over the past 25 yr, a large number of studies have been conducted to improve our knowledge of seismic hazard in this region. One of the decision-making concerns of Grenoble's public authorities, as managers of a large number of public buildings, is to know not only the seismic-prone regions, the variability of seismic hazard due to site effects and the city's overall vulnerability, but also the level of seismic risk and exposure for the entire city, also compared to other natural or/and domestic hazards. Our seismic risk analysis uses a probabilistic approach for regional and local hazards and the vulnerability assessment of buildings. Its applicability to Grenoble offers the advantage of being based on knowledge acquired by previous projects conducted over the years. This paper aims to compare the level of seismic risk with that of other risks and to introduce the notion of risk acceptability in order to offer guidance in the management of seismic risk. This notion of acceptability, which is now part of seismic risk consideration for existing buildings in Switzerland, is relevant in moderately seismic-prone countries like France.

  9. Methodology for seismic PSA of NPPs

    International Nuclear Information System (INIS)

    Jirsa, P.

    1999-09-01

    A general methodology is outlined for seismic PSA (probabilistic safety assessment). The main objectives of seismic PSA include: description of the course of an event; understanding the most probable failure sequences; gaining insight into the overall probability of reactor core damage; identification of the main seismic risk contributors; identification of the range of peak ground accelerations contributing significantly to the plant risk; and comparison of the seismic risk with risks from other events. The results of seismic PSA are typically compared with those of internal PSA and of PSA of other external events. If the results of internal and external PSA are available, sensitivity studies and cost benefit analyses are performed prior to any decision regarding corrective actions. If the seismic PSA involves analysis of the containment, useful information can be gained regarding potential seismic damage of the containment. (P.A.)

  10. Time-reversibility in seismic sequences: Application to the seismicity of Mexican subduction zone

    Science.gov (United States)

    Telesca, L.; Flores-Márquez, E. L.; Ramírez-Rojas, A.

    2018-02-01

    In this paper we investigate the time-reversibility of series associated with the seismicity of five seismic areas of the subduction zone beneath the Southwest Pacific Mexican coast, applying the horizontal visibility graph method to the series of earthquake magnitudes, interevent times, interdistances and magnitude increments. We applied the Kullback-Leibler divergence D that is a metric for quantifying the degree of time-irreversibility in time series. Our findings suggest that among the five seismic areas, Jalisco-Colima is characterized by time-reversibility in all the four seismic series. Our results are consistent with the peculiar seismo-tectonic characteristics of Jalisco-Colima, which is the closest to the Middle American Trench and belongs to the Mexican volcanic arc.

  11. Seismic microzonation of Bangalore, India

    Indian Academy of Sciences (India)

    Evaluation of seismic hazards and microzonation of cities enable us to characterize the potential seismic areas which have similar exposures to haz- ards of earthquakes, and these results can be used for designing new structures or retrofitting the existing ones. Study of seismic hazard and preparation of microzonation ...

  12. Seismic and dynamic qualification methods

    International Nuclear Information System (INIS)

    Lin, C.W.

    1985-01-01

    This book presents the papers given at a conference on seismic effects on nuclear power plants. Topics considered at the conference included seismic qualification of equipment, multifrequency test methodologies, damping in piping systems, the amplification factor, thermal insulation, welded joints, and response factors for seismic risk analysis of piping

  13. Seismic safety programme at NPP Paks. Propositions for coordinated international activity in seismic safety of the WWER-440 V-213

    International Nuclear Information System (INIS)

    Katona, T.

    1995-01-01

    This paper presents the Paks NPP seismic safety program, highlighting the specifics of the WWER-440/213 type in operation, and the results of work obtained so far. It covers the following scope: establishment of the seismic safety program (original seismic design, current requirements, principles and structure of the seismic safety program); implementation of the seismic safety program (assessing the seismic hazard of the site, development of the new concept of seismic safety for the NPP, assessing the seismic resistance of the building and the technology); realization of the seismic safety of higher level (technical solutions, drawings, realization); ideas and propositions for coordinated international activity

  14. The Machine within the Machine

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Although Virtual Machines are widespread across CERN, you probably won't have heard of them unless you work for an experiment. Virtual machines - known as VMs - allow you to create a separate machine within your own, allowing you to run Linux on your Mac, or Windows on your Linux - whatever combination you need.   Using a CERN Virtual Machine, a Linux analysis software runs on a Macbook. When it comes to LHC data, one of the primary issues collaborations face is the diversity of computing environments among collaborators spread across the world. What if an institute cannot run the analysis software because they use different operating systems? "That's where the CernVM project comes in," says Gerardo Ganis, PH-SFT staff member and leader of the CernVM project. "We were able to respond to experimentalists' concerns by providing a virtual machine package that could be used to run experiment software. This way, no matter what hardware they have ...

  15. Integrated system for seismic evaluations

    International Nuclear Information System (INIS)

    Xu, J.; Philippacopoulos, A.J.; Miller, C.A.; Costantino, C.J.; Graves, H.

    1989-01-01

    This paper describes the various features of the Seismic Module of the CARES system (Computer Analysis for Rapid Evaluation of Structures). This system was developed by Brookhaven National Laboratory (BNL) for the US Nuclear Regulatory Commission to perform rapid evaluations of structural behavior and capability of nuclear power plant facilities. The CARES is structured in a modular format. Each module performs a specific type of analysis i.e., static or dynamic, linear or nonlinear, etc. This paper describes the features of the Seismic Module in particular. The development of the Seismic Module of the CARES system is based on an approach which incorporates all major aspects of seismic analysis currently employed by the industry into an integrated system that allows for carrying out interactively computations of structural response to seismic motions. The code operates on a PC computer system and has multi-graphics capabilities. It has been designed with user friendly features and it allows for interactive manipulation of various analysis phases during the seismic design process. The capabilities of the seismic module include (a) generation of artificial time histories compatible with given design ground response spectra, (b) development of Power Spectral Density (PSD) functions associated with the seismic input, (c) deconvolution analysis using vertically propagating shear waves through a given soil profile, and (d) development of in-structure response spectra or corresponding PSD's. It should be pointed out that these types of analyses can also be performed individually by using available computer codes such as FLUSH, SAP, etc. The uniqueness of the CARES, however, lies on its ability to perform all required phases of the seismic analysis in an integrated manner. 5 refs., 6 figs

  16. Seismic Symphonies

    Science.gov (United States)

    Strinna, Elisa; Ferrari, Graziano

    2015-04-01

    The project started in 2008 as a sound installation, a collaboration between an artist, a barrel organ builder and a seismologist. The work differs from other attempts of sound transposition of seismic records. In this case seismic frequencies are not converted automatically into the "sound of the earthquake." However, it has been studied a musical translation system that, based on the organ tonal scale, generates a totally unexpected sequence of sounds which is intended to evoke the emotions aroused by the earthquake. The symphonies proposed in the project have somewhat peculiar origins: they in fact come to life from the translation of graphic tracks into a sound track. The graphic tracks in question are made up by copies of seismograms recorded during some earthquakes that have taken place around the world. Seismograms are translated into music by a sculpture-instrument, half a seismograph and half a barrel organ. The organ plays through holes practiced on paper. Adapting the documents to the instrument score, holes have been drilled on the waves' peaks. The organ covers about three tonal scales, starting from heavy and deep sounds it reaches up to high and jarring notes. The translation of the seismic records is based on a criterion that does match the highest sounds to larger amplitudes with lower ones to minors. Translating the seismogram in the organ score, the larger the amplitude of recorded waves, the more the seismogram covers the full tonal scale played by the barrel organ and the notes arouse an intense emotional response in the listener. Elisa Strinna's Seismic Symphonies installation becomes an unprecedented tool for emotional involvement, through which can be revived the memory of the greatest disasters of over a century of seismic history of the Earth. A bridge between art and science. Seismic Symphonies is also a symbolic inversion: the instrument of the organ is most commonly used in churches, and its sounds are derived from the heavens and

  17. Comparison of seismic isolation concepts for FBR

    International Nuclear Information System (INIS)

    Shiojiri, H.; Mazda, T.; Kasai, H.; Kanda, J.N.; Kubo, T.; Madokoro, M.; Shimomura, T.; Nojima, O.

    1989-01-01

    This paper seeks to verify the reliability and effectiveness of seismic isolation for FBR. Some results of the preliminary study of the program are described. Seismic isolation concepts and corresponding seismic isolation devices were selected. Three kinds of seismically-isolated FBR plant concepts were developed by applying promising seismic isolation concepts to the non-isolated FBR plant, and by developing plant component layout plans and building structural designs. Each plant was subjected to seismic response analysis and reduction in the amount of material of components and buildings were estimated for each seismic isolation concepts. Research and development items were evaluated

  18. Seismic source characterization for the 2014 update of the U.S. National Seismic Hazard Model

    Science.gov (United States)

    Moschetti, Morgan P.; Powers, Peter; Petersen, Mark D.; Boyd, Oliver; Chen, Rui; Field, Edward H.; Frankel, Arthur; Haller, Kathleen; Harmsen, Stephen; Mueller, Charles S.; Wheeler, Russell; Zeng, Yuehua

    2015-01-01

    We present the updated seismic source characterization (SSC) for the 2014 update of the National Seismic Hazard Model (NSHM) for the conterminous United States. Construction of the seismic source models employs the methodology that was developed for the 1996 NSHM but includes new and updated data, data types, source models, and source parameters that reflect the current state of knowledge of earthquake occurrence and state of practice for seismic hazard analyses. We review the SSC parameterization and describe the methods used to estimate earthquake rates, magnitudes, locations, and geometries for all seismic source models, with an emphasis on new source model components. We highlight the effects that two new model components—incorporation of slip rates from combined geodetic-geologic inversions and the incorporation of adaptively smoothed seismicity models—have on probabilistic ground motions, because these sources span multiple regions of the conterminous United States and provide important additional epistemic uncertainty for the 2014 NSHM.

  19. Seismic Data Gathering and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-02-01

    Three recent earthquakes in the last seven years have exceeded their design basis earthquake values (so it is implied that damage to SSC’s should have occurred). These seismic events were recorded at North Anna (August 2011, detailed information provided in [Virginia Electric and Power Company Memo]), Fukushima Daichii and Daini (March 2011 [TEPCO 1]), and Kaswazaki-Kariwa (2007, [TEPCO 2]). However, seismic walk downs at some of these plants indicate that very little damage occurred to safety class systems and components due to the seismic motion. This report presents seismic data gathered for two of the three events mentioned above and recommends a path for using that data for two purposes. One purpose is to determine what margins exist in current industry standard seismic soil-structure interaction (SSI) tools. The second purpose is the use the data to validated seismic site response tools and SSI tools. The gathered data represents free field soil and in-structure acceleration time histories data. Gathered data also includes elastic and dynamic soil properties and structural drawings. Gathering data and comparing with existing models has potential to identify areas of uncertainty that should be removed from current seismic analysis and SPRA approaches. Removing uncertainty (to the extent possible) from SPRA’s will allow NPP owners to make decisions on where to reduce risk. Once a realistic understanding of seismic response is established for a nuclear power plant (NPP) then decisions on needed protective measures, such as SI, can be made.

  20. Seismic Risk Perception compared with seismic Risk Factors

    Science.gov (United States)

    Crescimbene, Massimo; La Longa, Federica; Pessina, Vera; Pino, Nicola Alessandro; Peruzza, Laura

    2016-04-01

    The communication of natural hazards and their consequences is one of the more relevant ethical issues faced by scientists. In the last years, social studies have provided evidence that risk communication is strongly influenced by the risk perception of people. In order to develop effective information and risk communication strategies, the perception of risks and the influencing factors should be known. A theory that offers an integrative approach to understanding and explaining risk perception is still missing. To explain risk perception, it is necessary to consider several perspectives: social, psychological and cultural perspectives and their interactions. This paper presents the results of the CATI survey on seismic risk perception in Italy, conducted by INGV researchers on funding by the DPC. We built a questionnaire to assess seismic risk perception, with a particular attention to compare hazard, vulnerability and exposure perception with the real data of the same factors. The Seismic Risk Perception Questionnaire (SRP-Q) is designed by semantic differential method, using opposite terms on a Likert scale to seven points. The questionnaire allows to obtain the scores of five risk indicators: Hazard, Exposure, Vulnerability, People and Community, Earthquake Phenomenon. The questionnaire was administered by telephone interview (C.A.T.I.) on a statistical sample at national level of over 4,000 people, in the period January -February 2015. Results show that risk perception seems be underestimated for all indicators considered. In particular scores of seismic Vulnerability factor are extremely low compared with house information data of the respondents. Other data collected by the questionnaire regard Earthquake information level, Sources of information, Earthquake occurrence with respect to other natural hazards, participation at risk reduction activities and level of involvement. Research on risk perception aims to aid risk analysis and policy-making by

  1. Multicomponent seismic applications in coalbed methane development

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, D.; Trend, S. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

    2004-07-01

    Seismic applications for coalbed methane (CBM) development are used to address the following challenges: lateral continuity of coal zones; vertical continuity of coal seams; permeability of cleats and fractures; coal quality and gas content; wet versus dry coal zones; and, monitoring storage of greenhouse gases. This paper presented a brief description of existing seismic programs, including 2-D and 3-D surface seismic surveys; multicomponent seismic surveys; vertical seismic profiles; cross-well seismic surveys; and, time-lapse seismic surveys. A comparative evaluation of their use in the Horseshoe Canyon Formation and the Ardley Formation was presented. The study showed that variations in reservoir properties resulting from gas production and dewatering can be effectively imaged using seismic surveys. Seismic surveys are useful in reservoir management, monitoring sweep efficiency during enhanced natural gas from coal (NGC) production, monitoring disposal of produced water and verifying storage of carbon dioxide for carbon credits. tabs., figs.

  2. Seismic protection

    International Nuclear Information System (INIS)

    Herbert, R.

    1988-01-01

    To ensure that a nuclear reactor or other damage-susceptible installation is, so far as possible, tripped and already shut down before the arrival of an earthquake shock at its location, a ring of monitoring seismic sensors is provided around it, each sensor being spaced from it by a distance (possibly several kilometres) such that (taking into account the seismic-shock propagation velocity through the intervening ground) a shock monitored by the sensor and then advancing to the installation site will arrive there later than a warning signal emitted by the sensor and received at the installation, by an interval sufficient to allow the installation to trip and shut down, or otherwise assume an optimum anti-seismic mode, in response to the warning signal. Extra sensors located in boreholes may define effectively a three-dimensional (hemispherical) sensing boundary rather than a mere two-dimensional ring. (author)

  3. Induced Seismicity

    Science.gov (United States)

    Keranen, Katie M.; Weingarten, Matthew

    2018-05-01

    The ability of fluid-generated subsurface stress changes to trigger earthquakes has long been recognized. However, the dramatic rise in the rate of human-induced earthquakes in the past decade has created abundant opportunities to study induced earthquakes and triggering processes. This review briefly summarizes early studies but focuses on results from induced earthquakes during the past 10 years related to fluid injection in petroleum fields. Study of these earthquakes has resulted in insights into physical processes and has identified knowledge gaps and future research directions. Induced earthquakes are challenging to identify using seismological methods, and faults and reefs strongly modulate spatial and temporal patterns of induced seismicity. However, the similarity of induced and natural seismicity provides an effective tool for studying earthquake processes. With continuing development of energy resources, increased interest in carbon sequestration, and construction of large dams, induced seismicity will continue to pose a hazard in coming years.

  4. Pickering seismic safety margin

    International Nuclear Information System (INIS)

    Ghobarah, A.; Heidebrecht, A.C.; Tso, W.K.

    1992-06-01

    A study was conducted to recommend a methodology for the seismic safety margin review of existing Canadian CANDU nuclear generating stations such as Pickering A. The purpose of the seismic safety margin review is to determine whether the nuclear plant has sufficient seismic safety margin over its design basis to assure plant safety. In this review process, it is possible to identify the weak links which might limit the seismic performance of critical structures, systems and components. The proposed methodology is a modification the EPRI (Electric Power Research Institute) approach. The methodology includes: the characterization of the site margin earthquake, the definition of the performance criteria for the elements of a success path, and the determination of the seismic withstand capacity. It is proposed that the margin earthquake be established on the basis of using historical records and the regional seismo-tectonic and site specific evaluations. The ability of the components and systems to withstand the margin earthquake is determined by database comparisons, inspection, analysis or testing. An implementation plan for the application of the methodology to the Pickering A NGS is prepared

  5. Seismic safety research program plan

    International Nuclear Information System (INIS)

    1987-05-01

    This document presents a plan for seismic research to be performed by the Structural and Seismic Engineering Branch in the Office of Nuclear Regulatory Research. The plan describes the regulatory needs and related research necessary to address the following issues: uncertainties in seismic hazard, earthquakes larger than the design basis, seismic vulnerabilities, shifts in building frequency, piping design, and the adequacy of current criteria and methods. In addition to presenting current and proposed research within the NRC, the plan discusses research sponsored by other domestic and foreign sources

  6. Link Between the Seismic Events and the Different Seismic Precursor Phenomena

    Directory of Open Access Journals (Sweden)

    Mirela GHEORGHITA

    2009-12-01

    Full Text Available This article presents an analysis of the earthquake prediction methods, highlighting mainly the VLF and LF electromagnetic waves seismic precursors’ monitoring method and the correlation among these in order to obtain a more precise result. It is well known the fact that there are lots of links between the seismic events occurrence and different phenomena that predict their occurrence, such as theelectromagnetic field, Earth movement, gaseous content of radon and hydrogen within the soil, or within the underground waters. This paper aims to demonstrate the close link between the seismic events and the electromagnetic wave propagation anomalies, which are recorded before the advent of an earthquake.

  7. Robotics for mining control

    Energy Technology Data Exchange (ETDEWEB)

    1986-11-01

    In 1982 surveys of the mining industry revealed no applications of robotics existed and none were planned. This report provides a general overview of automation in the mining industry since this point in time. Roof control electronics, gas monitoring, jumbo drill automation, remote and sensor- controlled continuous miners, automated trolley trucks, roof bolting and screening machines are examples of technology available today. The report concludes with recommendations as to six potential research areas. 25 refs.

  8. Site response assessment using borehole seismic records

    Energy Technology Data Exchange (ETDEWEB)

    Park, Donghee; Chang, Chunjoong; Choi, Weonhack [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    In regions with high seismic activity, such as Japan, the Western United States and Taiwan, borehole seismometers installed deep underground are used to monitor seismic activity during the course of seismic wave propagation at various depths and to study the stress changes due to earthquakes and analyze the connection to fault movements. The Korea Meteorological Administration (KMA) and the Korea Institute of Geology and Mining (KIGAM) have installed and are operating borehole seismometers at a depth of 70∼100 meters for the precise determination of epicenters. Also, Korea Hydro and Nuclear Power Co., Ltd. (KHNP) has installed and is operating 2 borehole seismic stations near Weolseong area to observe at a depth of 140 meters seismic activities connected to fault activity. KHNP plans to operate in the second half of 2014 a borehole seismic station for depths less than 300 and 600 meters in order to study the seismic response characteristics in deep strata. As a basic study for analyzing ground motion response characteristics at depths of about 300 to 600 meters in connection with the deep geological disposal of spent nuclear fuel, the present study examined the background noise response characteristics of the borehole seismic station operated by KHNP. In order to analyze the depth-dependent impact of seismic waves at deeper depths than in Korea, seismic data collected by Japan's KIK-net seismic stations were used and the seismic wave characteristics analyzed by size and depth. In order to analyze the borehole seismic observation data from the seismic station operated by KHNP, this study analyzed the background noise characteristics by using a probability density function.

  9. Site response assessment using borehole seismic records

    International Nuclear Information System (INIS)

    Park, Donghee; Chang, Chunjoong; Choi, Weonhack

    2014-01-01

    In regions with high seismic activity, such as Japan, the Western United States and Taiwan, borehole seismometers installed deep underground are used to monitor seismic activity during the course of seismic wave propagation at various depths and to study the stress changes due to earthquakes and analyze the connection to fault movements. The Korea Meteorological Administration (KMA) and the Korea Institute of Geology and Mining (KIGAM) have installed and are operating borehole seismometers at a depth of 70∼100 meters for the precise determination of epicenters. Also, Korea Hydro and Nuclear Power Co., Ltd. (KHNP) has installed and is operating 2 borehole seismic stations near Weolseong area to observe at a depth of 140 meters seismic activities connected to fault activity. KHNP plans to operate in the second half of 2014 a borehole seismic station for depths less than 300 and 600 meters in order to study the seismic response characteristics in deep strata. As a basic study for analyzing ground motion response characteristics at depths of about 300 to 600 meters in connection with the deep geological disposal of spent nuclear fuel, the present study examined the background noise response characteristics of the borehole seismic station operated by KHNP. In order to analyze the depth-dependent impact of seismic waves at deeper depths than in Korea, seismic data collected by Japan's KIK-net seismic stations were used and the seismic wave characteristics analyzed by size and depth. In order to analyze the borehole seismic observation data from the seismic station operated by KHNP, this study analyzed the background noise characteristics by using a probability density function

  10. Evaluation of stress and saturation effects on seismic velocity and electrical resistivity - laboratory testing of rock samples

    Science.gov (United States)

    Vilhelm, Jan; Jirků, Jaroslav; Slavík, Lubomír; Bárta, Jaroslav

    2016-04-01

    Repository, located in a deep geological formation, is today considered the most suitable solution for disposal of spent nuclear fuel and high-level waste. The geological formations, in combination with an engineered barrier system, should ensure isolation of the waste from the environment for thousands of years. For long-term monitoring of such underground excavations special monitoring systems are developed. In our research we developed and tested monitoring system based on repeated ultrasonic time of flight measurement and electrical resistivity tomography (ERT). As a test site Bedřichov gallery in the northern Bohemia was selected. This underground gallery in granitic rock was excavated using Tunnel Boring Machine (TBM). The seismic high-frequency measurements are performed by pulse-transmission technique directly on the rock wall using one seismic source and three receivers in the distances of 1, 2 and 3 m. The ERT measurement is performed also on the rock wall using 48 electrodes. The spacing between electrodes is 20 centimeters. An analysis of relation of seismic velocity and electrical resistivity on water saturation and stress state of the granitic rock is necessary for the interpretation of both seismic monitoring and ERT. Laboratory seismic and resistivity measurements were performed. One series of experiments was based on uniaxial loading of dry and saturated granitic samples. The relation between stress state and ultrasonic wave velocities was tested separately for dry and saturated rock samples. Other experiments were focused on the relation between electrical resistivity of the rock sample and its saturation level. Rock samples with different porosities were tested. Acknowledgments: This work was partially supported by the Technology Agency of the Czech Republic, project No. TA 0302408

  11. NRC systematic evaluation program: seismic review

    International Nuclear Information System (INIS)

    Levin, H.A.

    1980-01-01

    The NRC Systematic Evaluation Program is currently making an assessment of the seismic design safety of 11 older nuclear power plant facilities. The general review philosophy and review criteria relative to seismic input, structural response, and equipment functionability are presented, including the rationale for the development of these guidelines considering the significant evolution of seismic design criteria since these plants were originally licensed. Technical approaches thought more realistic in light of current knowledge are utilized. Initial findings for plants designed to early seismic design procedures suggest that with minor exceptions, these plants possess adequate seismic design margins when evaluated against the intent of current criteria. However, seismic qualification of electrical equipment has been identified as a subject which requires more in-depth evaluation

  12. Integrated system for seismic evaluations

    International Nuclear Information System (INIS)

    Xu, J.; Philippacopoulos, A.J.; Miller, C.A.; Costantino, C.J.; Graves, H.

    1989-01-01

    This paper describes the various features of the seismic module of the CARES system (computer analysis for rapid evaluation of structures). This system was developed to perform rapid evaluations of structural behavior and capability of nuclear power plant facilities. The CARES is structural in a modular format. Each module performs a specific type of analysis i.e., static or dynamic, linear or nonlinear, etc. This paper describes the features of the seismic module in particular. The development of the seismic modules of the CARES system is based on an approach which incorporates major aspects of seismic analysis currently employed by the industry into an integrated system that allows for carrying out interactively computations of structural response to seismic motions. The code operates on a PC computer system and has multi-graphics capabilities

  13. Seismic facies; Facies sismicas

    Energy Technology Data Exchange (ETDEWEB)

    Johann, Paulo Roberto Schroeder [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao Corporativo. Gerencia de Reservas e Reservatorios]. E-mail: johann@petrobras.com.br

    2004-11-01

    The method presented herein describes the seismic facies as representations of curves and vertical matrixes of the lithotypes proportions. The seismic facies are greatly interested in capturing the spatial distributions (3D) of regionalized variables, as for example, lithotypes, sedimentary facies groups and/ or porosity and/or other properties of the reservoirs and integrate them into the 3D geological modeling (Johann, 1997). Thus when interpreted as curves or vertical matrixes of proportions, seismic facies allow us to build a very important tool for structural analysis of regionalized variables. The matrixes have an important application in geostatistical modeling. In addition, this approach provides results about the depth and scale of the wells profiles, that is, seismic data is integrated to the characterization of reservoirs in depth maps and in high resolution maps. The link between the different necessary technical phases involved in the classification of the segments of seismic traces is described herein in groups of predefined traces of two approaches: a) not supervised and b) supervised by the geological knowledge available on the studied reservoir. The multivariate statistical methods used to obtain the maps of the seismic facies units are interesting tools to be used to provide a lithostratigraphic and petrophysical understanding of a petroleum reservoir. In the case studied these seismic facies units are interpreted as representative of the depositional system as a part of the Namorado Turbiditic System, Namorado Field, Campos Basin.Within the scope of PRAVAP 19 (Programa Estrategico de Recuperacao Avancada de Petroleo - Strategic Program of Advanced Petroleum Recovery) some research work on algorithms is underway to select new optimized attributes to apply seismic facies. One example is the extraction of attributes based on the wavelet transformation and on the time-frequency analysis methodology. PRAVAP is also carrying out research work on an

  14. User's manual for seismic analysis code 'SONATINA-2V'

    Energy Technology Data Exchange (ETDEWEB)

    Hanawa, Satoshi; Iyoku, Tatsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2001-08-01

    The seismic analysis code, SONATINA-2V, has been developed to analyze the behavior of the HTTR core graphite components under seismic excitation. The SONATINA-2V code is a two-dimensional computer program capable of analyzing the vertical arrangement of the HTTR graphite components, such as fuel blocks, replaceable reflector blocks, permanent reflector blocks, as well as their restraint structures. In the analytical model, each block is treated as rigid body and is restrained by dowel pins which restrict relative horizontal movement but allow vertical and rocking motions between upper and lower blocks. Moreover, the SONATINA-2V code is capable of analyzing the core vibration behavior under both simultaneous excitations of vertical and horizontal directions. The SONATINA-2V code is composed of the main program, pri-processor for making the input data to SONATINA-2V and post-processor for data processing and making the graphics from analytical results. Though the SONATINA-2V code was developed in order to work in the MSP computer system of Japan Atomic Energy Research Institute (JAERI), the computer system was abolished with the technical progress of computer. Therefore, improvement of this analysis code was carried out in order to operate the code under the UNIX machine, SR8000 computer system, of the JAERI. The users manual for seismic analysis code, SONATINA-2V, including pri- and post-processor is given in the present report. (author)

  15. Research on performance-based seismic design criteria

    Institute of Scientific and Technical Information of China (English)

    谢礼立; 马玉宏

    2002-01-01

    The seismic design criterion adopted in the existing seismic design codes is reviewed. It is pointed out that the presently used seismic design criterion is not satisfied with the requirements of nowadays social and economic development. A new performance-based seismic design criterion that is composed of three components is presented in this paper. It can not only effectively control the economic losses and casualty, but also ensure the building(s function in proper operation during earthquakes. The three components are: classification of seismic design for buildings, determination of seismic design intensity and/or seismic design ground motion for controlling seismic economic losses and casualties, and determination of the importance factors in terms of service periods of buildings. For controlling the seismic human losses, the idea of socially acceptable casualty level is presented and the (Optimal Economic Decision Model( and (Optimal Safe Decision Model( are established. Finally, a new method is recommended for calculating the importance factors of structures by adjusting structures service period on the base of more important structure with longer service period than the conventional ones. Therefore, the more important structure with longer service periods will be designed for higher seismic loads, in case the exceedance probability of seismic hazard in different service period is same.

  16. Effect of Machining Velocity in Nanoscale Machining Operations

    International Nuclear Information System (INIS)

    Islam, Sumaiya; Khondoker, Noman; Ibrahim, Raafat

    2015-01-01

    The aim of this study is to investigate the generated forces and deformations of single crystal Cu with (100), (110) and (111) crystallographic orientations at nanoscale machining operation. A nanoindenter equipped with nanoscratching attachment was used for machining operations and in-situ observation of a nano scale groove. As a machining parameter, the machining velocity was varied to measure the normal and cutting forces. At a fixed machining velocity, different levels of normal and cutting forces were generated due to different crystallographic orientations of the specimens. Moreover, after machining operation percentage of elastic recovery was measured and it was found that both the elastic and plastic deformations were responsible for producing a nano scale groove within the range of machining velocities from 250-1000 nm/s. (paper)

  17. Seismic data acquisition systems

    International Nuclear Information System (INIS)

    Kolvankar, V.G.; Nadre, V.N.; Rao, D.S.

    1989-01-01

    Details of seismic data acquisition systems developed at the Bhabha Atomic Research Centre, Bombay are reported. The seismic signals acquired belong to different signal bandwidths in the band from 0.02 Hz to 250 Hz. All these acquisition systems are built around a unique technique of recording multichannel data on to a single track of an audio tape and in digital form. Techniques of how these signals in different bands of frequencies were acquired and recorded are described. Method of detecting seismic signals and its performance is also discussed. Seismic signals acquired in different set-ups are illustrated. Time indexing systems for different set-ups and multichannel waveform display systems which form essential part of the data acquisition systems are also discussed. (author). 13 refs., 6 figs., 1 tab

  18. Probabilistic Seismic Hazard Analysis for Yemen

    Directory of Open Access Journals (Sweden)

    Rakesh Mohindra

    2012-01-01

    Full Text Available A stochastic-event probabilistic seismic hazard model, which can be used further for estimates of seismic loss and seismic risk analysis, has been developed for the territory of Yemen. An updated composite earthquake catalogue has been compiled using the databases from two basic sources and several research publications. The spatial distribution of earthquakes from the catalogue was used to define and characterize the regional earthquake source zones for Yemen. To capture all possible scenarios in the seismic hazard model, a stochastic event set has been created consisting of 15,986 events generated from 1,583 fault segments in the delineated seismic source zones. Distribution of horizontal peak ground acceleration (PGA was calculated for all stochastic events considering epistemic uncertainty in ground-motion modeling using three suitable ground motion-prediction relationships, which were applied with equal weight. The probabilistic seismic hazard maps were created showing PGA and MSK seismic intensity at 10% and 50% probability of exceedance in 50 years, considering local soil site conditions. The resulting PGA for 10% probability of exceedance in 50 years (return period 475 years ranges from 0.2 g to 0.3 g in western Yemen and generally is less than 0.05 g across central and eastern Yemen. The largest contributors to Yemen’s seismic hazard are the events from the West Arabian Shield seismic zone.

  19. The influence of backfill on seismicity

    CSIR Research Space (South Africa)

    Hemp, DA

    1990-09-01

    Full Text Available , that the seismicity has been reduced in areas where backfill had been placed. A factor complicating the evaluation of backfill on seismicity is the effect of geological structures on seismicity....

  20. Towards a Systematic Search for Triggered Seismic Events in the USA

    Science.gov (United States)

    Tang, V.; Chao, K.; Van der Lee, S.

    2017-12-01

    Dynamic triggering of small earthquakes and tectonic tremor by small stress variations associated with passing surface waves from large-magnitude teleseismic earthquakes have been observed in seismically active regions in the western US. Local stress variations as small as 5 10 kPa can suffice to advance slip on local faults. Observations of such triggered events share certain distinct characteristics. With an eye towards an eventual application of machine learning, we began a systematic search for dynamically triggered seismic events in the USA that have these characteristics. Such a systematic survey has the potential to help us to better understand the fundamental process of dynamic triggering and hazards implied by it. Using visual inspection on top of timing and frequency based selection criteria for these seismic phenomena, our search yielded numerous false positives, indicating the challenge posed by moving from ad-hoc observations of dynamic triggering to a systematic search that also includes a catalog of non-triggering, even when sufficient stress variations are supplied. Our search includes a dozen large earthquakes that occurred during the tenure of USArray. One of these earthquakes (11 April 2012 Mw8.6 Sumatra), for example, was observed by USArray-TA stations in the Midwest and other station networks (such as PB and UW), and yielded candidate-triggered events at 413 stations. We kept 79 of these observations after closer visual inspection of the observed events suggested distinct P and S arrivals from a local earthquake, or a tremor modulation with the same period as the surface wave, among other criteria. We confirmed triggered seismic events in 63 stations along the western plate boundary where triggered events have previously been observed. We also newly found triggered tremor sources in eastern Oregon and Yellowstone, and candidate-triggered earthquake sources in New Mexico and Minnesota. Learning whether 14 of remaining candidates are confirmed

  1. Seismic soil-structure interaction with consideration of spatial incoherence of seismic ground motions: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Wen S., E-mail: wen.tseng@rizzoassoc.com [Paul C. Rizzo Associates, Inc., Western Region, 2201 Broadway, Suite 400, Oakland, CA 94612 (United States); Lilhanand, Kiat; Hamasaki, Don; Garcia, Julio A. [Paul C. Rizzo Associates, Inc., Western Region, 2201 Broadway, Suite 400, Oakland, CA 94612 (United States); Srinivasan, Ram [AREVA, NP, Inc., 6399 San Ignacio Avenue, San Jose, CA 95119 (United States)

    2014-04-01

    This paper presents a case study of seismic soil-structure interaction (SSI) analysis with consideration of spatial incoherence of seismic input ground motions. The SSI analyses were performed using the SASSI computer program for the Auxiliary Control Building (ACB) structure of an existing nuclear power plant on a hard rock site located in the Center and Eastern United States (CEUS) region. The incoherent seismic input motions for the hard rock site used for the analyses were generated using the computer program INCOH that works together with SASSI. The objective of the analyses was to generate maximum seismic response parameters for assessment of potential impact of newly developed site-specific (ground motion) response spectra (SSRS) on the seismic design of the ACB and potential benefits that could be gained by considering spatial incoherence of seismic input motions. Maximum seismic response values for selected response parameters of interest were generated with both SSRS-compatible coherent and incoherent seismic input motions. Comparisons were made of the corresponding maximum response parameter values and in-structure (acceleration) response spectra (ISRS) generated for both the coherent and incoherent motion inputs. These comparisons indicate that, by incorporating incoherence of ground motions in the seismic input, the maximum response values reduces and the ISRS peak amplitudes in the high frequency range (>10 Hz) also reduce from the corresponding response values resulting from the coherent motion input. The amount of ISRS-amplitude reduction increases as the spectral frequency increases, as expected. Such reductions can be as much as 20–50%. This case study demonstrates that, for a CEUS hard rock site where relatively high high-frequency in the seismic input response spectra exist, consideration of spatial incoherence of input motions would result in substantial benefits in reducing the high-frequency seismic responses. Such benefits are especially

  2. Seismicity and seismic hazard in Sabah, East Malaysia from earthquake and geodetic data

    Science.gov (United States)

    Gilligan, A.; Rawlinson, N.; Tongkul, F.; Stephenson, R.

    2017-12-01

    While the levels of seismicity are low in most of Malaysia, the state of Sabah in northern Borneo has moderate levels of seismicity. Notable earthquakes in the region include the 1976 M6.2 Lahad Datu earthquake and the 2015 M6 Ranau earthquake. The recent Ranau earthquake resulted in the deaths of 18 people on Mt Kinabalu, an estimated 100 million RM ( US$23 million) damage to buildings, roads, and infrastructure from shaking, and flooding, reduced water quality, and damage to farms from landslides. Over the last 40 years the population of Sabah has increased to over four times what it was in 1976, yet seismic hazard in Sabah remains poorly understood. Using seismic and geodetic data we hope to better quantify the hazards posed by earthquakes in Sabah, and thus help to minimize risk. In order to do this we need to know about the locations of earthquakes, types of earthquakes that occur, and faults that are generating them. We use data from 15 MetMalaysia seismic stations currently operating in Sabah to develop a region-specific velocity model from receiver functions and a pre-existing surface wave model. We use this new velocity model to (re)locate earthquakes that occurred in Sabah from 2005-2016, including a large number of aftershocks from the 2015 Ranau earthquake. We use a probabilistic nonlinear earthquake location program to locate the earthquakes and then refine their relative locations using a double difference method. The recorded waveforms are further used to obtain moment tensor solutions for these earthquakes. Earthquake locations and moment tensor solutions are then compared with the locations of faults throughout Sabah. Faults are identified from high-resolution IFSAR images and subsequent fieldwork, with a particular focus on the Lahad Datau and Ranau areas. Used together, these seismic and geodetic data can help us to develop a new seismic hazard model for Sabah, as well as aiding in the delivery of outreach activities regarding seismic hazard

  3. Seismic design practices for power systems

    International Nuclear Information System (INIS)

    Schiff, A.J.

    1991-01-01

    In this paper, the evolution of seismic design practices in electric power systems is reviewed. In California the evolution had led to many installation practices that are directed at improving the seismic ruggedness of power system facilities, particularly high voltage substation equipment. The primary means for substantiating the seismic ruggedness of important, hard to analyze substation equipment is through vibration testing. Current activities include system evaluations, development of emergency response plans and their exercise, and review elements that impact the entire system, such as energy control centers and communication systems. From a national perspective there is a need to standardize seismic specifications, identify a seismic specialist within each utility and enhance communications among these specialists. There is a general need to incorporate good seismic design practices on a national basis emphasizing new construction

  4. Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert [Applied Technology Associates, Albuquerque, NM (United States); Laughlin, Darren [Applied Technology Associates, Albuquerque, NM (United States); Brune, Robert [Applied Technology Associates, Albuquerque, NM (United States)

    2016-10-19

    Rotational motion is increasingly understood to be a significant part of seismic wave motion. Rotations can be important in earthquake strong motion and in Induced Seismicity Monitoring. Rotational seismic data can also enable shear selectivity and improve wavefield sampling for vertical geophones in 3D surveys, among other applications. However, sensor technology has been a limiting factor to date. The US Department of Energy (DOE) and Applied Technology Associates (ATA) are funding a multi-year project that is now entering Phase 2 to develop and deploy a new generation of rotational sensors for validation of rotational seismic applications. Initial focus is on induced seismicity monitoring, particularly for Enhanced Geothermal Systems (EGS) with fracturing. The sensors employ Magnetohydrodynamic (MHD) principles with broadband response, improved noise floors, robustness, and repeatability. This paper presents a summary of Phase 1 results and Phase 2 status.

  5. Seismic shear wall ISP NUPEC's seismic ultimate dynamic response test. Comparison report

    International Nuclear Information System (INIS)

    1996-01-01

    In the seismic design of a nuclear power plant, evaluation of the ultimate strength of the nuclear reactor building is an important subject for assessment of seismic reliability of the plant. In order to carry out the evaluation, the response characteristics of reinforced concrete seismic shear walls up to their ultimate state have to be understood. For this purpose, there is a need to develop reliable non-linear response analysis methods which enables the reliable ultimate strength evaluation of nuclear reactor buildings. Along with this need, many computer codes have been developed. These computer codes are compared. (K.A.)

  6. Seismic evaluation of the Mors Dome

    International Nuclear Information System (INIS)

    Kreitz, E.

    1982-01-01

    The ''Seismic Case History'' of the Mors saltdome was already published in detail by ELSAM/ELKRAFT so only a few important points need to be mentioned here: (a) Processing and interpretation of the seismic material. (b) Stratigraphic classification of the most important seismic reflection horizons. (c) Construction of the depth sections and description of the saltdome model. (d) Investigations of the problematic salt overhang using interactive seismic modelling. (EG)

  7. Mine-induced seismicity at East-Rand proprietary mines

    CSIR Research Space (South Africa)

    Milev, AM

    1995-09-01

    Full Text Available Mining results in seismic activity of varying intensity, from small micro seismic events to larger seismic events, often associated with significant seismic induced damages. This work deals with the understanding of the present seismicity...

  8. Prediction of Machine Tool Condition Using Support Vector Machine

    International Nuclear Information System (INIS)

    Wang Peigong; Meng Qingfeng; Zhao Jian; Li Junjie; Wang Xiufeng

    2011-01-01

    Condition monitoring and predicting of CNC machine tools are investigated in this paper. Considering the CNC machine tools are often small numbers of samples, a condition predicting method for CNC machine tools based on support vector machines (SVMs) is proposed, then one-step and multi-step condition prediction models are constructed. The support vector machines prediction models are used to predict the trends of working condition of a certain type of CNC worm wheel and gear grinding machine by applying sequence data of vibration signal, which is collected during machine processing. And the relationship between different eigenvalue in CNC vibration signal and machining quality is discussed. The test result shows that the trend of vibration signal Peak-to-peak value in surface normal direction is most relevant to the trend of surface roughness value. In trends prediction of working condition, support vector machine has higher prediction accuracy both in the short term ('One-step') and long term (multi-step) prediction compared to autoregressive (AR) model and the RBF neural network. Experimental results show that it is feasible to apply support vector machine to CNC machine tool condition prediction.

  9. Machine learning for the automatic detection of anomalous events

    Science.gov (United States)

    Fisher, Wendy D.

    In this dissertation, we describe our research contributions for a novel approach to the application of machine learning for the automatic detection of anomalous events. We work in two different domains to ensure a robust data-driven workflow that could be generalized for monitoring other systems. Specifically, in our first domain, we begin with the identification of internal erosion events in earth dams and levees (EDLs) using geophysical data collected from sensors located on the surface of the levee. As EDLs across the globe reach the end of their design lives, effectively monitoring their structural integrity is of critical importance. The second domain of interest is related to mobile telecommunications, where we investigate a system for automatically detecting non-commercial base station routers (BSRs) operating in protected frequency space. The presence of non-commercial BSRs can disrupt the connectivity of end users, cause service issues for the commercial providers, and introduce significant security concerns. We provide our motivation, experimentation, and results from investigating a generalized novel data-driven workflow using several machine learning techniques. In Chapter 2, we present results from our performance study that uses popular unsupervised clustering algorithms to gain insights to our real-world problems, and evaluate our results using internal and external validation techniques. Using EDL passive seismic data from an experimental laboratory earth embankment, results consistently show a clear separation of events from non-events in four of the five clustering algorithms applied. Chapter 3 uses a multivariate Gaussian machine learning model to identify anomalies in our experimental data sets. For the EDL work, we used experimental data from two different laboratory earth embankments. Additionally, we explore five wavelet transform methods for signal denoising. The best performance is achieved with the Haar wavelets. We achieve up to 97

  10. Seismic forecast using geostatistics

    International Nuclear Information System (INIS)

    Grecu, Valeriu; Mateiciuc, Doru

    2007-01-01

    The main idea of this research direction consists in the special way of constructing a new type of mathematical function as being a correlation between a computed statistical quantity and another physical quantity. This type of function called 'position function' was taken over by the authors of this study in the field of seismology with the hope of solving - at least partially - the difficult problem of seismic forecast. The geostatistic method of analysis focuses on the process of energy accumulation in a given seismic area, completing this analysis by a so-called loading function. This function - in fact a temporal function - describes the process of energy accumulation during a seismic cycle from a given seismic area. It was possible to discover a law of evolution of the seismic cycles that was materialized in a so-called characteristic function. This special function will help us to forecast the magnitude and the occurrence moment of the largest earthquake in the analysed area. Since 2000, the authors have been evolving to a new stage of testing: real - time analysis, in order to verify the quality of the method. There were five large earthquakes forecasts. (authors)

  11. Annual Hanford seismic report - fiscal year 1996

    International Nuclear Information System (INIS)

    Hartshorn, D.C.; Reidel, S.P.

    1996-12-01

    Seismic monitoring (SM) at the Hanford Site was established in 1969 by the US Geological Survey (USGS) under a contract with the US Atomic Energy Commission. Since 1980, the program has been managed by several contractors under the US Department of Energy (USDOE). Effective October 1, 1996, the Seismic Monitoring workscope, personnel, and associated contracts were transferred to the USDOE Pacific Northwest National Laboratory (PNNL). SM is tasked to provide an uninterrupted collection and archives of high-quality raw and processed seismic data from the Hanford Seismic Network (HSN) located on and encircling the Hanford Site. SM is also tasked to locate and identify sources of seismic activity and monitor changes in the historical pattern of seismic activity at the Hanford Site. The data compiled are used by SM, Waste Management, and engineering activities at the Hanford Site to evaluate seismic hazards and seismic design for the Site

  12. Advanced Seismic While Drilling System

    Energy Technology Data Exchange (ETDEWEB)

    Robert Radtke; John Fontenot; David Glowka; Robert Stokes; Jeffery Sutherland; Ron Evans; Jim Musser

    2008-06-30

    A breakthrough has been discovered for controlling seismic sources to generate selectable low frequencies. Conventional seismic sources, including sparkers, rotary mechanical, hydraulic, air guns, and explosives, by their very nature produce high-frequencies. This is counter to the need for long signal transmission through rock. The patent pending SeismicPULSER{trademark} methodology has been developed for controlling otherwise high-frequency seismic sources to generate selectable low-frequency peak spectra applicable to many seismic applications. Specifically, we have demonstrated the application of a low-frequency sparker source which can be incorporated into a drill bit for Drill Bit Seismic While Drilling (SWD). To create the methodology of a controllable low-frequency sparker seismic source, it was necessary to learn how to maximize sparker efficiencies to couple to, and transmit through, rock with the study of sparker designs and mechanisms for (a) coupling the sparker-generated gas bubble expansion and contraction to the rock, (b) the effects of fluid properties and dynamics, (c) linear and non-linear acoustics, and (d) imparted force directionality. After extensive seismic modeling, the design of high-efficiency sparkers, laboratory high frequency sparker testing, and field tests were performed at the University of Texas Devine seismic test site. The conclusion of the field test was that extremely high power levels would be required to have the range required for deep, 15,000+ ft, high-temperature, high-pressure (HTHP) wells. Thereafter, more modeling and laboratory testing led to the discovery of a method to control a sparker that could generate low frequencies required for deep wells. The low frequency sparker was successfully tested at the Department of Energy Rocky Mountain Oilfield Test Center (DOE RMOTC) field test site in Casper, Wyoming. An 8-in diameter by 26-ft long SeismicPULSER{trademark} drill string tool was designed and manufactured by TII

  13. Seismic analysis and testing of nuclear power plants

    International Nuclear Information System (INIS)

    1979-01-01

    The following subjects are discussed in this guide: General Recommendations for seismic classification, loading combinations and allowable limits; seismic analysis methods; implications for seismic design; seismic testing and qualification; seismic instrumentation; modelling techniques; material property characterization; seismic response of soil deposits and earth structures; liquefaction and ground failure; slope stability; sloshing effects in water pools; qualification testing by means of the transport vehicle

  14. Demonstration of improved seismic source inversion method of tele-seismic body wave

    Science.gov (United States)

    Yagi, Y.; Okuwaki, R.

    2017-12-01

    Seismic rupture inversion of tele-seismic body wave has been widely applied to studies of large earthquakes. In general, tele-seismic body wave contains information of overall rupture process of large earthquake, while the tele-seismic body wave is inappropriate for analyzing a detailed rupture process of M6 7 class earthquake. Recently, the quality and quantity of tele-seismic data and the inversion method has been greatly improved. Improved data and method enable us to study a detailed rupture process of M6 7 class earthquake even if we use only tele-seismic body wave. In this study, we demonstrate the ability of the improved data and method through analyses of the 2016 Rieti, Italy earthquake (Mw 6.2) and the 2016 Kumamoto, Japan earthquake (Mw 7.0) that have been well investigated by using the InSAR data set and the field observations. We assumed the rupture occurring on a single fault plane model inferred from the moment tensor solutions and the aftershock distribution. We constructed spatiotemporal discretized slip-rate functions with patches arranged as closely as possible. We performed inversions using several fault models and found that the spatiotemporal location of large slip-rate area was robust. In the 2016 Kumamoto, Japan earthquake, the slip-rate distribution shows that the rupture propagated to southwest during the first 5 s. At 5 s after the origin time, the main rupture started to propagate toward northeast. First episode and second episode correspond to rupture propagation along the Hinagu fault and the Futagawa fault, respectively. In the 2016 Rieti, Italy earthquake, the slip-rate distribution shows that the rupture propagated to up-dip direction during the first 2 s, and then rupture propagated toward northwest. From both analyses, we propose that the spatiotemporal slip-rate distribution estimated by improved inversion method of tele-seismic body wave has enough information to study a detailed rupture process of M6 7 class earthquake.

  15. Environmentally Friendly Machining

    CERN Document Server

    Dixit, U S; Davim, J Paulo

    2012-01-01

    Environment-Friendly Machining provides an in-depth overview of environmentally-friendly machining processes, covering numerous different types of machining in order to identify which practice is the most environmentally sustainable. The book discusses three systems at length: machining with minimal cutting fluid, air-cooled machining and dry machining. Also covered is a way to conserve energy during machining processes, along with useful data and detailed descriptions for developing and utilizing the most efficient modern machining tools. Researchers and engineers looking for sustainable machining solutions will find Environment-Friendly Machining to be a useful volume.

  16. Visualization of volumetric seismic data

    Science.gov (United States)

    Spickermann, Dela; Böttinger, Michael; Ashfaq Ahmed, Khawar; Gajewski, Dirk

    2015-04-01

    Mostly driven by demands of high quality subsurface imaging, highly specialized tools and methods have been developed to support the processing, visualization and interpretation of seismic data. 3D seismic data acquisition and 4D time-lapse seismic monitoring are well-established techniques in academia and industry, producing large amounts of data to be processed, visualized and interpreted. In this context, interactive 3D visualization methods proved to be valuable for the analysis of 3D seismic data cubes - especially for sedimentary environments with continuous horizons. In crystalline and hard rock environments, where hydraulic stimulation techniques may be applied to produce geothermal energy, interpretation of the seismic data is a more challenging problem. Instead of continuous reflection horizons, the imaging targets are often steep dipping faults, causing a lot of diffractions. Without further preprocessing these geological structures are often hidden behind the noise in the data. In this PICO presentation we will present a workflow consisting of data processing steps, which enhance the signal-to-noise ratio, followed by a visualization step based on the use the commercially available general purpose 3D visualization system Avizo. Specifically, we have used Avizo Earth, an extension to Avizo, which supports the import of seismic data in SEG-Y format and offers easy access to state-of-the-art 3D visualization methods at interactive frame rates, even for large seismic data cubes. In seismic interpretation using visualization, interactivity is a key requirement for understanding complex 3D structures. In order to enable an easy communication of the insights gained during the interactive visualization process, animations of the visualized data were created which support the spatial understanding of the data.

  17. Manufacture and test of seismic bellows for ITER magnet feeder

    International Nuclear Information System (INIS)

    Liu, Chen; Lu, Kun; Sheng, Liang; Song, Yuntao; Su, Jinjin; Su, Man; Gung, Chenyu

    2016-01-01

    Highlights: • The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. • The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. • 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. • A full tensile test with 315 mm of stretching from its nominal length was conducted. • The prototype bellows was qualified for its leak tightness (less than 1 × 10 −9 Pam 3 /s of helium) at all time during the qualification test. - Abstract: This paper presents the key manufacturing and testing processes of the prototype ITER feeder seismic bellows. The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. Each inner and outer bellows was supported in dedicated molds and formed by a hydraulic pressure machine rated at 800 tons. The double bellows were constructed by welding individual collars to the end flanges. The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. This was followed by 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. After the mechanical fatigue test, a full tensile test with 315 mm of stretching from its nominal length was conducted. Helium leak tests, with the sensitivity of the helium leak detector set to 1 × 10 −9 Pa m 3 /s of helium, were performed at different stages of pressure and mechanical tests. The prototype bellows was qualified for its leak tightness at all time during the qualification test.

  18. Manufacture and test of seismic bellows for ITER magnet feeder

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chen, E-mail: liuchen@ipp.ac.cn [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Lu, Kun [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Sheng, Liang [AEROSUN-TOLA Expansion Joint Co., Ltd., Jiangjun Road No. 199, Nanjing (China); Song, Yuntao; Su, Jinjin [Institute of Plasma Physics Chinese Academy of Sciences, ShuShanhu Road No. 350, Hefei (China); Su, Man; Gung, Chenyu [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul-lez-Durance (France)

    2016-11-01

    Highlights: • The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. • The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. • 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. • A full tensile test with 315 mm of stretching from its nominal length was conducted. • The prototype bellows was qualified for its leak tightness (less than 1 × 10{sup −9} Pam{sup 3}/s of helium) at all time during the qualification test. - Abstract: This paper presents the key manufacturing and testing processes of the prototype ITER feeder seismic bellows. The design of the double bellows was iterated with the results of analysis based on the Expansion Joint Manufacturers Association (EJMA) standard. Each inner and outer bellows was supported in dedicated molds and formed by a hydraulic pressure machine rated at 800 tons. The double bellows were constructed by welding individual collars to the end flanges. The seismic bellows was tested with cyclic pressurization of the interlayer space to 2 bars absolute pressure for 5 cycles. This was followed by 200 cycles of tensile fatigue test with 90 mm of stretching from the nominal design length. After the mechanical fatigue test, a full tensile test with 315 mm of stretching from its nominal length was conducted. Helium leak tests, with the sensitivity of the helium leak detector set to 1 × 10{sup −9} Pa m{sup 3}/s of helium, were performed at different stages of pressure and mechanical tests. The prototype bellows was qualified for its leak tightness at all time during the qualification test.

  19. Seismic modelling of shallow coalfields

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, D.C. (University of Calgary, Calgary, Alberta (Canada). Dept. of Geology and Geophysics.)

    1987-01-01

    This study was undertaken in order to determine whether reflection seismic surveys can be used to map stratigraphic and structural detail of shallow Plains-type coal deposits. Two coalfields in central Alberta were used to examine and determine optimum acquisition parameters for reflection seismic surveys in such settings. The study was based on 1-D and 2-D numerical seismic modelling using sonic and density well logs to formulate a layered earth model. Additional objectives were to interpret the reflection seismic data in terms of geologic features in the study area, and to investigate the relationship between vertical resolution and field acquisition geometry. 27 refs., 41 figs.

  20. Complex researches on substantiation of construction and seismic stability of large dams in seismic region

    International Nuclear Information System (INIS)

    Negmatullaev, S.Kh.; Yasunov, P.A.

    2001-01-01

    This article is devoted to complex researches on substantiation of construction and seismic stability of large dams (Nurec hydroelectric power station) in seismic region. Geological, seismological, model, and engineering investigations are discussed in this work. At construction of Nurec hydroelectric power station the rich experience is accumulated. This experience can be used in analogous seismically active regions at construction similar hydroelectric power stations.

  1. Seismicity, seismic input and site effects in the Sahel-Algiers region (north Algeria)

    International Nuclear Information System (INIS)

    Harbi, A.; Maouche, S.; Oussadou, F.; Vaccari, F.; Aoudia, A.; Panza, G.F.; Benouar, D.

    2005-07-01

    Algiers city is located in a seismogenic zone. To reduce the impact of seismic risk in this capital city, a realistic modelling of the seismic ground motion using the hybrid method that combines the finite-differences method and the modal summation, is conducted. For this purpose, a complete database in terms of geological, geophysical and earthquake data is constructed. A critical re-appraisal of the seismicity of the zone (2.25 deg. E-3.50 deg. E, 36.50 deg. N-37.00 deg. N) is performed and an earthquake list, for the period 1359-2002, is compiled. The analysis of existing and newly retrieved macroseismic information allowed the definition of earthquake parameters of macroseismic events for which a degree of reliability is assigned. Geological cross-sections have been built up to model the seismic ground motion in the city, caused by the 1989 Mont-Chenoua and the 1924 Douera earthquakes; a set of synthetic seismograms and response spectral ratio is produced for Algiers. The numerical results show that the soft sediments in Algiers centre are responsible of the noticed amplification of the seismic ground motion. (author)

  2. Development of seismic hazard analysis in Japan

    International Nuclear Information System (INIS)

    Itoh, T.; Ishii, K.; Ishikawa, Y.; Okumura, T.

    1987-01-01

    In recent years, seismic risk assessment of the nuclear power plant have been conducted increasingly in various countries, particularly in the United States to evaluate probabilistically the safety of existing plants under earthquake loading. The first step of the seismic risk assessment is the seismic hazard analysis, in which the relationship between the maximum earthquake ground motions at the plant site and their annual probability of exceedance, i.e. the seismic hazard curve, is estimated. In this paper, seismic hazard curves are evaluated and examined based on historical earthquake records model, in which seismic sources are modeled with area-sources, for several different sites in Japan. A new evaluation method is also proposed to compute the response spectra of the earthquake ground motions in connection with estimating the probabilistic structural response. Finally the numerical result of probabilistic risk assessment for a base-isolated three story RC structure, in which the frequency of seismic induced structural failure is evaluated combining the seismic hazard analysis, is described briefly

  3. Seismic rupture study using near-source data: application to seismic hazard assessment

    International Nuclear Information System (INIS)

    Hernandez, Bruno

    2000-01-01

    This work presents seismic source studies using near-field data. In accordance with the quality and the quantity of available data we developed and applied various methods to characterize the seismic source. Macro-seismic data are used to verify if simple and robust methods used on recent instrumental earthquakes may provide a good tool to calibrate historical events in France. These data are often used to characterize earthquakes to be taken into account for seismic hazard assessment in moderate seismicity regions. Geodetic data (SAR, GPS) are used to estimate the slip distribution on the fault during the 1992, Landers, California earthquake. These data are also used to precise the location and the geometry of the main events of the 1997, Colfiorito, central Italy, earthquake sequence. Finally, the strong motions contain the most complete information about rupture process. These data are used to discriminate between two possible fault planes of the 1999, north India, Chamoli earthquake. The strong motions recorded close to the 1999, Mexico, Oaxaca earthquake are used to constrain the rupture history. Strong motions a.re also used in combination with geodetic data to access the rupture history of the Landers earthquake and the main events of the Colfiorito seismic sequence. For the Landers earthquake, the data quality and complementarity offered the possibility to describe the rupture development with accuracy. The large heterogeneities in both slip amplitude and rupture velocity variations suggest that the rupture propagates by breaking successive asperities rather than by propagating like a pulse at constant velocity. The rupture front slows as it encounters barriers and accelerates within main asperities. (author)

  4. Seismic fragility analysis of a nuclear building based on probabilistic seismic hazard assessment and soil-structure interaction analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, R.; Ni, S.; Chen, R.; Han, X.M. [CANDU Energy Inc, Mississauga, Ontario (Canada); Mullin, D. [New Brunswick Power, Point Lepreau, New Brunswick (Canada)

    2016-09-15

    Seismic fragility analyses are conducted as part of seismic probabilistic safety assessment (SPSA) for nuclear facilities. Probabilistic seismic hazard assessment (PSHA) has been undertaken for a nuclear power plant in eastern Canada. Uniform Hazard Spectra (UHS), obtained from the PSHA, is characterized by high frequency content which differs from the original plant design basis earthquake spectral shape. Seismic fragility calculations for the service building of a CANDU 6 nuclear power plant suggests that the high frequency effects of the UHS can be mitigated through site response analysis with site specific geological conditions and state-of-the-art soil-structure interaction analysis. In this paper, it is shown that by performing a detailed seismic analysis using the latest technology, the conservatism embedded in the original seismic design can be quantified and the seismic capacity of the building in terms of High Confidence of Low Probability of Failure (HCLPF) can be improved. (author)

  5. Vertical seismic profiling and integration with reflection seismic studies at Laxemar, 2000

    International Nuclear Information System (INIS)

    Juhlin, C.; Bergman, B.; Cosma, C.; Keskinen, J.; Enescu, N.

    2002-02-01

    Vertical seismic profile (VSP) data were acquired in October 2000 in the 1700 m deep KLX02 borehole, near Laxemar in southeastern Sweden. The objectives of the VSP were to image reflectors in the borehole for correlation with surface seismic and borehole data, study the signal penetration of explosive versus mechanical sources and determine the seismic velocity as a function of depth. Five principal source points were used, one located close to the KLX02 wellhead and 4 others that were offset by about 200 m to 400 m. An explosive source was only used at the wellhead and consisted of 15 grams of dynamite in 90 cm deep shot holes in bedrock. A swept impact seismic source (SIST) was also used at the wellhead, as well as at the other four offset source points. The primary SIST source consisted of a computer controlled mechanical hammer mounted on a tractor. By activating the hammer over a 15 second sweep length, the total energy transferred to the ground is on the same order as that produced by the dynamite. The recorded data are then processed to generate seismic records that are equivalent to a single impact source. A smaller hand held SIST source was also tested at the wellhead. Tests of both the tractor mounted source and dynamite were made at a location offset somewhat from the wellhead at a site containing loose sediments at the surface. Full waveform sonic, resistivity and gamma logs were also acquired in conjunction the VSP survey. A comparison between the explosive and large SIST source shows that comparable energy levels are produced by the two methods. The SIST source appears to be more stable in terms of the energy level, although the frequency content of data are somewhat lower. However, its most significant advantage is the low cost of preparation of the source points and the speed of the acquisition. Numerous reflections are observed on the VSP, as is the case on the surface seismic, implying a complex structure in the vicinity of the KLX02 borehole

  6. Vertical seismic profiling and integration with reflection seismic studies at Laxemar, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Juhlin, C.; Bergman, B. [Uppsala Univ. (Sweden); Cosma, C.; Keskinen, J.; Enescu, N. [Vibrometric Oy, Helsinki (Finland)

    2002-02-01

    Vertical seismic profile (VSP) data were acquired in October 2000 in the 1700 m deep KLX02 borehole, near Laxemar in southeastern Sweden. The objectives of the VSP were to image reflectors in the borehole for correlation with surface seismic and borehole data, study the signal penetration of explosive versus mechanical sources and determine the seismic velocity as a function of depth. Five principal source points were used, one located close to the KLX02 wellhead and 4 others that were offset by about 200 m to 400 m. An explosive source was only used at the wellhead and consisted of 15 grams of dynamite in 90 cm deep shot holes in bedrock. A swept impact seismic source (SIST) was also used at the wellhead, as well as at the other four offset source points. The primary SIST source consisted of a computer controlled mechanical hammer mounted on a tractor. By activating the hammer over a 15 second sweep length, the total energy transferred to the ground is on the same order as that produced by the dynamite. The recorded data are then processed to generate seismic records that are equivalent to a single impact source. A smaller hand held SIST source was also tested at the wellhead. Tests of both the tractor mounted source and dynamite were made at a location offset somewhat from the wellhead at a site containing loose sediments at the surface. Full waveform sonic, resistivity and gamma logs were also acquired in conjunction the VSP survey. A comparison between the explosive and large SIST source shows that comparable energy levels are produced by the two methods. The SIST source appears to be more stable in terms of the energy level, although the frequency content of data are somewhat lower. However, its most significant advantage is the low cost of preparation of the source points and the speed of the acquisition. Numerous reflections are observed on the VSP, as is the case on the surface seismic, implying a complex structure in the vicinity of the KLX02 borehole

  7. Spots of Seismic Danger Extracted by Properties of Low-Frequency Seismic Noise

    Science.gov (United States)

    Lyubushin, Alexey

    2013-04-01

    A new method of seismic danger estimate is presented which is based on using properties of low-frequency seismic noise from broadband networks. Two statistics of noise waveforms are considered: multi-fractal singularity spectrum support width D and minimum normalized entropy En of squared orthogonal wavelet coefficients. The maps of D and En are plotted in the moving time window. Let us call the regions extracted by low values of D and high values of En as "spots of seismic danger" - SSD. Mean values of D and En are strongly anti-correlated - that is why statistics D and En extract the same SSD. Nevertheless their mutual considering is expedient because these parameters are based on different approaches. The physical mechanism which underlies the method is consolidation of small blocks of the Earth's crust into the large one before the strong earthquake. This effect has a consequence that seismic noise does not include spikes which are connected with mutual movements of small blocks. The absence of irregular spikes in the noise follows the decreasing of D and increasing of entropy En. The stability in space and size of the SSD provides estimates of the place and energy of the probable future earthquake. The increasing or decreasing of SSD size and minimum or maximum values of D and En within SSD allows estimate the trend of seismic danger. The method is illustrating by the analysis of seismic noise from broadband seismic network F-net in Japan [1-5]. Statistically significant decreasing of D allowed a hypothesis about approaching Japan to a future seismic catastrophe to be formulated at the middle of 2008. The peculiarities of correlation coefficient estimate within 1 year time window between median values of D and generalized Hurst exponent allowed to make a decision that starting from July of 2010 Japan come to the state of waiting strong earthquake [3]. The method extracted a huge SSD near Japan which includes the region of future Tohoku mega-earthquake and the

  8. Induced Seismicity Monitoring System

    Science.gov (United States)

    Taylor, S. R.; Jarpe, S.; Harben, P.

    2014-12-01

    There are many seismological aspects associated with monitoring of permanent storage of carbon dioxide (CO2) in geologic formations. Many of these include monitoring underground gas migration through detailed tomographic studies of rock properties, integrity of the cap rock and micro seismicity with time. These types of studies require expensive deployments of surface and borehole sensors in the vicinity of the CO2 injection wells. Another problem that may exist in CO2 sequestration fields is the potential for damaging induced seismicity associated with fluid injection into the geologic reservoir. Seismic hazard monitoring in CO2 sequestration fields requires a seismic network over a spatially larger region possibly having stations in remote settings. Expensive observatory-grade seismic systems are not necessary for seismic hazard deployments or small-scale tomographic studies. Hazard monitoring requires accurate location of induced seismicity to magnitude levels only slightly less than that which can be felt at the surface (e.g. magnitude 1), and the frequencies of interest for tomographic analysis are ~1 Hz and greater. We have developed a seismo/acoustic smart sensor system that can achieve the goals necessary for induced seismicity monitoring in CO2 sequestration fields. The unit is inexpensive, lightweight, easy to deploy, can operate remotely under harsh conditions and features 9 channels of recording (currently 3C 4.5 Hz geophone, MEMS accelerometer and microphone). An on-board processor allows for satellite transmission of parameter data to a processing center. Continuous or event-detected data is kept on two removable flash SD cards of up to 64+ Gbytes each. If available, data can be transmitted via cell phone modem or picked up via site visits. Low-power consumption allows for autonomous operation using only a 10 watt solar panel and a gel-cell battery. The system has been successfully tested for long-term (> 6 months) remote operations over a wide range

  9. Final Report: Seismic Hazard Assessment at the PGDP

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhinmeng [KY Geological Survey, Univ of KY

    2007-06-01

    Selecting a level of seismic hazard at the Paducah Gaseous Diffusion Plant for policy considerations and engineering design is not an easy task because it not only depends on seismic hazard, but also on seismic risk and other related environmental, social, and economic issues. Seismic hazard is the main focus. There is no question that there are seismic hazards at the Paducah Gaseous Diffusion Plant because of its proximity to several known seismic zones, particularly the New Madrid Seismic Zone. The issues in estimating seismic hazard are (1) the methods being used and (2) difficulty in characterizing the uncertainties of seismic sources, earthquake occurrence frequencies, and ground-motion attenuation relationships. This report summarizes how input data were derived, which methodologies were used, and what the hazard estimates at the Paducah Gaseous Diffusion Plant are.

  10. Green's function representations for seismic interferometry

    NARCIS (Netherlands)

    Wapenaar, C.P.A.; Fokkema, J.T.

    2006-01-01

    The term seismic interferometry refers to the principle of generating new seismic responses by crosscorrelating seismic observations at different receiver locations. The first version of this principle was derived by Claerbout (1968), who showed that the reflection response of a horizontally layered

  11. Seismic site evaluation practice and seismic design guide for NPP in Continent of China

    Energy Technology Data Exchange (ETDEWEB)

    Yuxian, Hu [State Seismological Bureau, Beijing, BJ (China). Inst. of Geophysics

    1997-03-01

    Energy resources, seismicity, NPP and related regulations of the Continent of China are briefly introduced in the beginning and two codes related to the seismic design of NPP, one on siting and another on design, are discussed in some detail. The one on siting is an official code of the State Seismological Bureau, which specifies the seismic safety evaluation requirements of various kinds of structures, from the most critic and important structures such as NPP to ordinary buildings, and including also engineering works in big cities. The one on seismic design of NPP is a draft subjected to publication now, which will be an official national code. The first one is somewhat unique but the second one is quite similar to those in the world. (author)

  12. Seismic site evaluation practice and seismic design guide for NPP in Continent of China

    International Nuclear Information System (INIS)

    Hu Yuxian

    1997-01-01

    Energy resources, seismicity, NPP and related regulations of the Continent of China are briefly introduced in the beginning and two codes related to the seismic design of NPP, one on siting and another on design, are discussed in some detail. The one on siting is an official code of the State Seismological Bureau, which specifies the seismic safety evaluation requirements of various kinds of structures, from the most critic and important structures such as NPP to ordinary buildings, and including also engineering works in big cities. The one on seismic design of NPP is a draft subjected to publication now, which will be an official national code. The first one is somewhat unique but the second one is quite similar to those in the world. (author)

  13. Preliminary consideration on the seismic actions recorded during the 2016 Central Italy seismic sequence

    Science.gov (United States)

    Carlo Ponzo, Felice; Ditommaso, Rocco; Nigro, Antonella; Nigro, Domenico S.; Iacovino, Chiara

    2017-04-01

    After the Mw 6.0 mainshock of August 24, 2016 at 03.36 a.m. (local time), with the epicenter located between the towns of Accumoli (province of Rieti), Amatrice (province of Rieti) and Arquata del Tronto (province of Ascoli Piceno), several activities were started in order to perform some preliminary evaluations on the characteristics of the recent seismic sequence in the areas affected by the earthquake. Ambient vibration acquisitions have been performed using two three-directional velocimetric synchronized stations, with a natural frequency equal to 0.5Hz and a digitizer resolution of equal to 24bit. The activities are continuing after the events of the seismic sequence of October 26 and October 30, 2016. In this paper, in order to compare recorded and code provision values in terms of peak (PGA, PGV and PGD), spectral and integral (Housner Intensity) seismic parameters, several preliminary analyses have been performed on accelerometric time-histories acquired by three near fault station of the RAN (Italian Accelerometric Network): Amatrice station (station code AMT), Norcia station (station code NRC) and Castelsantangelo sul Nera station (station code CNE). Several comparisons between the elastic response spectra derived from accelerometric recordings and the elastic demand spectra provided by the Italian seismic code (NTC 2008) have been performed. Preliminary results retrieved from these analyses highlight several apparent difference between experimental data and conventional code provision. Then, the ongoing seismic sequence appears compatible with the historical seismicity in terms of integral parameters, but not in terms of peak and spectral values. It seems appropriate to reconsider the necessity to revise the simplified design approach based on the conventional spectral values. Acknowledgements This study was partially funded by the Italian Department of Civil Protection within the project DPC-RELUIS 2016 - RS4 ''Seismic observatory of structures and

  14. Seismic Isolation Studies and Applications for Nuclear Facilities

    International Nuclear Information System (INIS)

    Choun, Young Sun

    2005-01-01

    Seismic isolation, which is being used worldwide for buildings, is a well-known technology to protect structures from destructive earthquakes. In spite of the many potential advantages of a seismic isolation, however, the applications of a seismic isolation to nuclear facilities have been very limited because of a lack of sufficient knowledge about the isolation practices. The most important advantage of seismic isolation applications in nuclear power plants is that the safety and reliability of the plants can be remarkably improved through the standardization of the structures and equipment regardless of the seismic conditions of the sites. The standardization of structures and equipment will reduce the capital cost and design/construction schedule for future plants. Also, a seismic isolation can facilitate decoupling of the design and development for equipment, piping, and components due to the use of the generic in-structure response spectra associated with the standardized plant. Moreover, a seismic isolation will improve the plant safety margin against the design basis earthquake (DBE) as well as a beyond design basis seismic event due to its superior seismic performance. A number of seismic isolation systems have been developed and tested since 1970s, and some of them have been applied to conventional structures in several countries of high seismicity. In the nuclear field, there have been many studies on the applicability of such seismic isolation systems, but the application of a seismic isolation is very limited. Currently, there are some discussions on the application of seismic isolation systems to nuclear facilities between the nuclear industries and the regulatory agencies in the U.S.. In the future, a seismic isolation for nuclear facilities will be one of the important issues in the nuclear industry. This paper summarizes the past studies and applications of a seismic isolation in the nuclear industry

  15. Application of Musical Information Retrieval (MIR Techniques to Seismic Facies Classification. Examples in Hydrocarbon Exploration

    Directory of Open Access Journals (Sweden)

    Paolo Dell’Aversana

    2016-12-01

    Full Text Available In this paper, we introduce a novel approach for automatic pattern recognition and classification of geophysical data based on digital music technology. We import and apply in the geophysical domain the same approaches commonly used for Musical Information Retrieval (MIR. After accurate conversion from geophysical formats (example: SEG-Y to musical formats (example: Musical Instrument Digital Interface, or briefly MIDI, we extract musical features from the converted data. These can be single-valued attributes, such as pitch and sound intensity, or multi-valued attributes, such as pitch histograms, melodic, harmonic and rhythmic paths. Using a real data set, we show that these musical features can be diagnostic for seismic facies classification in a complex exploration area. They can be complementary with respect to “conventional” seismic attributes. Using a supervised machine learning approach based on the k-Nearest Neighbors algorithm and on Automatic Neural Networks, we classify three gas-bearing channels. The good performance of our classification approach is confirmed by borehole data available in the same area.

  16. AcquisitionFootprintAttenuationDrivenbySeismicAttributes

    Directory of Open Access Journals (Sweden)

    Cuellar-Urbano Mayra

    2014-04-01

    Full Text Available Acquisition footprint, one of the major problems that PEMEX faces in seismic imaging, is noise highly correlated to the geometric array of sources and receivers used for onshore and offshore seismic acquisitions. It prevails in spite of measures taken during acquisition and data processing. This pattern, throughout the image, is easily confused with geological features and misguides seismic attribute computation. In this work, we use seismic data from PEMEX Exploración y Producción to show the conditioning process for removing random and coherent noise using linear filters. Geometric attributes used in a workflow were computed for obtaining an acquisition footprint noise model and adaptively subtract it from the seismic data.

  17. Implementation of A Better Choice Healthy Food and Drink Supply Strategy for staff and visitors in government-owned health facilities in Queensland, Australia.

    Science.gov (United States)

    Miller, Jane; Lee, Amanda; Obersky, Natalie; Edwards, Rachael

    2015-06-01

    The present paper reports on a quality improvement activity examining implementation of A Better Choice Healthy Food and Drink Supply Strategy for Queensland Health Facilities (A Better Choice). A Better Choice is a policy to increase supply and promotion of healthy foods and drinks and decrease supply and promotion of energy-dense, nutrient-poor choices in all food supply areas including food outlets, staff dining rooms, vending machines, tea trolleys, coffee carts, leased premises, catering, fundraising, promotion and advertising. An online survey targeted 278 facility managers to collect self-reported quantitative and qualitative data. Telephone interviews were sought concurrently with the twenty-five A Better Choice district contact officers to gather qualitative information. Public sector-owned and -operated health facilities in Queensland, Australia. One hundred and thirty-four facility managers and twenty-four district contact officers participated with response rates of 48.2% and 96.0%, respectively. Of facility managers, 78.4% reported implementation of more than half of the A Better Choice requirements including 24.6% who reported full strategy implementation. Reported implementation was highest in food outlets, staff dining rooms, tea trolleys, coffee carts, internal catering and drink vending machines. Reported implementation was more problematic in snack vending machines, external catering, leased premises and fundraising. Despite methodological challenges, the study suggests that policy approaches to improve the food and drink supply can be implemented successfully in public-sector health facilities, although results can be limited in some areas. A Better Choice may provide a model for improving food supply in other health and workplace settings.

  18. The Virtual Seismic Atlas Project: sharing the interpretation of seismic data

    Science.gov (United States)

    Butler, R.; Mortimer, E.; McCaffrey, B.; Stuart, G.; Sizer, M.; Clayton, S.

    2007-12-01

    Through the activities of academic research programs, national institutions and corporations, especially oil and gas companies, there is a substantial volume of seismic reflection data. Although the majority is proprietary and confidential, there are significant volumes of data that are potentially within the public domain and available for research. Yet the community is poorly connected to these data and consequently geological and other research using seismic reflection data is limited to very few groups of researchers. This is about to change. The Virtual Seismic Atlas (VSA) is generating an independent, free-to-use, community based internet resource that captures and shares the geological interpretation of seismic data globally. Images and associated documents are explicitly indexed using not only existing survey and geographical data but also on the geology they portray. By using "Guided Navigation" to search, discover and retrieve images, users are exposed to arrays of geological analogues that provide novel insights and opportunities for research and education. The VSA goes live, with evolving content and functionality, through 2008. There are opportunities for designed integration with other global data programs in the earth sciences.

  19. Seismic evaluation of existing nuclear power plants

    International Nuclear Information System (INIS)

    2003-01-01

    The IAEA nuclear safety standards publications address the site evaluation and the design of new nuclear power plants (NPPs), including seismic hazard assessment and safe seismic design, at the level of the Safety Requirements as well as at the level of dedicated Safety Guides. It rapidly became apparent that the existing nuclear safety standards documents were not adequate for handling specific issues in the seismic evaluation of existing NPPs, and that a dedicated document was necessary. This is the purpose of this Safety Report, which is written in the spirit of the nuclear safety standards and can be regarded as guidance for the interpretation of their intent. Worldwide experience shows that an assessment of the seismic capacity of an existing operating facility can be prompted for the following: (a) Evidence of a greater seismic hazard at the site than expected before, owing to new or additional data and/or to new methods; (b) Regulatory requirements, such as periodic safety reviews, to ensure that the plant has adequate margins for seismic loads; (c) Lack of anti-seismic design or poor anti-seismic design; (d) New technical finding such as vulnerability of some structures (masonry walls) or equipment (relays), other feedback and new experience from real earthquakes. Post-construction evaluation programmes evaluate the current capability of the plant to withstand the seismic concern and identify any necessary upgrades or changes in operating procedures. Seismic qualification is distinguished from seismic evaluation primarily in that seismic qualification is intended to be performed at the design stage of a plant, whereas seismic evaluation is intended to be applied after a plant has been constructed. Although some guidelines do exist for the evaluation of existing NPPs, these are not established at the level of a regulatory guide or its equivalent. Nevertheless, a number of existing NPPs throughout the world have been and are being subjected to review of their

  20. OGS improvements in 2012 in running the Northeastern Italy Seismic Network: the Ferrara VBB borehole seismic station

    Science.gov (United States)

    Pesaresi, Damiano; Romanelli, Marco; Barnaba, Carla; Bragato, Pier Luigi; Durì, Giorgio

    2013-04-01

    The Centro di Ricerche Sismologiche (CRS, Seismological Research Center) of the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Italian National Institute for Oceanography and Experimental Geophysics) in Udine (Italy) after the strong earthquake of magnitude M=6.4 occurred in 1976 in the Italian Friuli-Venezia Giulia region, started to operate the Northeastern Italy Seismic Network: it currently consists of 17 very sensitive broad band and 18 simpler short period seismic stations, all telemetered to and acquired in real time at the OGS-CRS data center in Udine. Real time data exchange agreements in place with other Italian, Slovenian, Austrian and Swiss seismological institutes lead to a total number of about 100 seismic stations acquired in real time, which makes the OGS the reference institute for seismic monitoring of Northeastern Italy. The southwestern edge of the OGS seismic network stands on the Po alluvial basin: earthquake localization and characterization in this area is affected by the presence of soft alluvial deposits. OGS ha already experience in running a local seismic network in high noise conditions making use of borehole installations in the case of the micro-seismicity monitoring of a local gas storage site for a private company. Following the ML=5.9 earthquake that struck the Emilia region around Ferrara in Northern Italy on May 20, 2012 at 02:03:53 UTC, a cooperation of Istituto Nazionale di Geofisica e Vulcanologia, OGS, the Comune di Ferrara and the University of Ferrara lead to the reinstallation of a previously existing very broad band (VBB) borehole seismic station in Ferrara. The aim of the OGS intervention was on one hand to extend its real time seismic monitoring capabilities toward South-West, including Ferrara and its surroundings, and on the other hand to evaluate the seismic response at the site. We will describe improvements in running the Northeastern Italy Seismic Network, including details of the Ferrara VBB

  1. NCSRR digital seismic network in Romania

    International Nuclear Information System (INIS)

    Aldea, A.; Albota, E.; Demetriu, S.; Poiata, N.; Kashima, T.

    2007-01-01

    Digital seismic instrumentation donated by Japan International Cooperation Agency (JICA) to the National Center for Seismic Risk Reduction (NCSRR, Romania) allowed the installation in 2003 of a new Romanian seismic network. In 2005-2006 the network was developed by investments from NCSRR within the budget ensured by Ministry of Transports, Construction and Tourism (MTCT). The NCSRR seismic network contains three types of instrumentation: (i) free-field stations - outside the capital city Bucharest (8 accelerometers), (ii) instrumented buildings - in Bucharest (5 buildings), and (iii) stations with free-field and borehole sensors - in Bucharest (8 sites with ground surface sensor and sensors in 15 boreholes with depths up to 153 m). Since its installation, the NCSRR network recorded more than 170 seismic motions from 26 earthquakes with moment magnitudes ranging from 3.2 to 6.0. The seismic instrumentation was accompanied by investigations of ground conditions and site response: PS logging tests, single-station and array microtremor measurements. The development of seismic monitoring in Romania is a major contribution of JICA Project, creating the premises for a better understanding and modelling of earthquake ground motion, site effects and building response. (authors)

  2. Hybrid machining processes perspectives on machining and finishing

    CERN Document Server

    Gupta, Kapil; Laubscher, R F

    2016-01-01

    This book describes various hybrid machining and finishing processes. It gives a critical review of the past work based on them as well as the current trends and research directions. For each hybrid machining process presented, the authors list the method of material removal, machining system, process variables and applications. This book provides a deep understanding of the need, application and mechanism of hybrid machining processes.

  3. Martian seismicity

    International Nuclear Information System (INIS)

    Goins, N.R.; Lazarewicz, A.R.

    1979-01-01

    During the Viking mission to Mars, the seismometer on Lander II collected approximately 0.24 Earth years of observations data, excluding periods of time dominated by wind-induced Lander vibration. The ''quiet-time'' data set contains no confirmed seismic events. A proper assessment of the significance of this fact requires quantitative estimates of the expected detection rate of the Viking seismometer. The first step is to calculate the minimum magnitude event detectable at a given distance, including the effects of geometric spreading, anelastic attenuation, seismic signal duration, seismometer frequency response, and possible poor ground coupling. Assuming various numerical quantities and a Martian seismic activity comparable to that of intraplate earthquakes, the appropriate integral gives an expected annual detection rate of 10 events, nearly all of which are local. Thus only two to three events would be expected in the observational period presently on hand and the lack of observed events is not in gross contradiction to reasonable expectations. Given the same assumptions, a seismometer 20 times more sensitive than the present instrument would be expected to detect about 120 events annually

  4. Multicomponent ensemble models to forecast induced seismicity

    Science.gov (United States)

    Király-Proag, E.; Gischig, V.; Zechar, J. D.; Wiemer, S.

    2018-01-01

    In recent years, human-induced seismicity has become a more and more relevant topic due to its economic and social implications. Several models and approaches have been developed to explain underlying physical processes or forecast induced seismicity. They range from simple statistical models to coupled numerical models incorporating complex physics. We advocate the need for forecast testing as currently the best method for ascertaining if models are capable to reasonably accounting for key physical governing processes—or not. Moreover, operational forecast models are of great interest to help on-site decision-making in projects entailing induced earthquakes. We previously introduced a standardized framework following the guidelines of the Collaboratory for the Study of Earthquake Predictability, the Induced Seismicity Test Bench, to test, validate, and rank induced seismicity models. In this study, we describe how to construct multicomponent ensemble models based on Bayesian weightings that deliver more accurate forecasts than individual models in the case of Basel 2006 and Soultz-sous-Forêts 2004 enhanced geothermal stimulation projects. For this, we examine five calibrated variants of two significantly different model groups: (1) Shapiro and Smoothed Seismicity based on the seismogenic index, simple modified Omori-law-type seismicity decay, and temporally weighted smoothed seismicity; (2) Hydraulics and Seismicity based on numerically modelled pore pressure evolution that triggers seismicity using the Mohr-Coulomb failure criterion. We also demonstrate how the individual and ensemble models would perform as part of an operational Adaptive Traffic Light System. Investigating seismicity forecasts based on a range of potential injection scenarios, we use forecast periods of different durations to compute the occurrence probabilities of seismic events M ≥ 3. We show that in the case of the Basel 2006 geothermal stimulation the models forecast hazardous levels

  5. LANL seismic screening method for existing buildings

    International Nuclear Information System (INIS)

    Dickson, S.L.; Feller, K.C.; Fritz de la Orta, G.O.

    1997-01-01

    The purpose of the Los Alamos National Laboratory (LANL) Seismic Screening Method is to provide a comprehensive, rational, and inexpensive method for evaluating the relative seismic integrity of a large building inventory using substantial life-safety as the minimum goal. The substantial life-safety goal is deemed to be satisfied if the extent of structural damage or nonstructural component damage does not pose a significant risk to human life. The screening is limited to Performance Category (PC) -0, -1, and -2 buildings and structures. Because of their higher performance objectives, PC-3 and PC-4 buildings automatically fail the LANL Seismic Screening Method and will be subject to a more detailed seismic analysis. The Laboratory has also designated that PC-0, PC-1, and PC-2 unreinforced masonry bearing wall and masonry infill shear wall buildings fail the LANL Seismic Screening Method because of their historically poor seismic performance or complex behavior. These building types are also recommended for a more detailed seismic analysis. The results of the LANL Seismic Screening Method are expressed in terms of separate scores for potential configuration or physical hazards (Phase One) and calculated capacity/demand ratios (Phase Two). This two-phase method allows the user to quickly identify buildings that have adequate seismic characteristics and structural capacity and screen them out from further evaluation. The resulting scores also provide a ranking of those buildings found to be inadequate. Thus, buildings not passing the screening can be rationally prioritized for further evaluation. For the purpose of complying with Executive Order 12941, the buildings failing the LANL Seismic Screening Method are deemed to have seismic deficiencies, and cost estimates for mitigation must be prepared. Mitigation techniques and cost-estimate guidelines are not included in the LANL Seismic Screening Method

  6. Seismic Prediction While Drilling (SPWD): Seismic exploration ahead of the drill bit using phased array sources

    Science.gov (United States)

    Jaksch, Katrin; Giese, Rüdiger; Kopf, Matthias

    2010-05-01

    In the case of drilling for deep reservoirs previous exploration is indispensable. In recent years the focus shifted more on geological structures like small layers or hydrothermal fault systems. Beside 2D- or 3D-seismics from the surface and seismic measurements like Vertical Seismic Profile (VSP) or Seismic While Drilling (SWD) within a borehole these methods cannot always resolute this structures. The resolution is worsen the deeper and smaller the sought-after structures are. So, potential horizons like small layers in oil exploration or fault zones usable for geothermal energy production could be failed or not identified while drilling. The application of a device to explore the geology with a high resolution ahead of the drill bit in direction of drilling would be of high importance. Such a device would allow adjusting the drilling path according to the real geology and would minimize the risk of discovery and hence the costs for drilling. Within the project SPWD a device for seismic exploration ahead of the drill bit will be developed. This device should allow the seismic exploration to predict areas about 50 to 100 meters ahead of the drill bit with a resolution of one meter. At the GFZ a first prototype consisting of different units for seismic sources, receivers and data loggers has been designed and manufactured. As seismic sources four standard magnetostrictive actuators and as receivers four 3-component-geophones are used. Every unit, actuator or geophone, can be rotated in steps of 15° around the longitudinal axis of the prototype to test different measurement configurations. The SPWD prototype emits signal frequencies of about 500 up to 5000 Hz which are significant higher than in VSP and SWD. An increased radiation of seismic wave energy in the direction of the borehole axis allows the view in areas to be drilled. Therefore, every actuator must be controlled independently of each other regarding to amplitude and phase of the source signal to

  7. Cooperative New Madrid seismic network

    International Nuclear Information System (INIS)

    Herrmann, R.B.; Johnston, A.C.

    1990-01-01

    The development and installation of components of a U.S. National Seismic Network (USNSN) in the eastern United States provides the basis for long term monitoring of eastern earthquakes. While the broad geographical extent of this network provides a uniform monitoring threshold for the purpose of identifying and locating earthquakes and while it will provide excellent data for defining some seismic source parameters for larger earthquakes through the use of waveform modeling techniques, such as depth and focal mechanism, by itself it will not be able to define the scaling of high frequency ground motions since it will not focus on any of the major seismic zones in the eastern U.S. Realizing this need and making use of a one time availability of funds for studying New Madrid earthquakes, Saint Louis University and Memphis State University successfully competed for funding in a special USGS RFP for New Madrid studies. The purpose of the proposal is to upgrade the present seismic networks run by these institutions in order to focus on defining the seismotectonics and ground motion scaling in the New Madrid Seismic Zone. The proposed network is designed both to complement the U.S. National Seismic Network and to make use of the capabilities of the communication links of that network

  8. Fast principal component analysis for stacking seismic data

    Science.gov (United States)

    Wu, Juan; Bai, Min

    2018-04-01

    Stacking seismic data plays an indispensable role in many steps of the seismic data processing and imaging workflow. Optimal stacking of seismic data can help mitigate seismic noise and enhance the principal components to a great extent. Traditional average-based seismic stacking methods cannot obtain optimal performance when the ambient noise is extremely strong. We propose a principal component analysis (PCA) algorithm for stacking seismic data without being sensitive to noise level. Considering the computational bottleneck of the classic PCA algorithm in processing massive seismic data, we propose an efficient PCA algorithm to make the proposed method readily applicable for industrial applications. Two numerically designed examples and one real seismic data are used to demonstrate the performance of the presented method.

  9. Conceptual design by analysis of KALIMER seismic isolation

    International Nuclear Information System (INIS)

    You, Bong; Koo, Kyung Hoi; Lee, Jae Han

    1996-06-01

    The objectives of this report are to preliminarily evaluate the seismic isolation performance of KALIMER (Korea Advance LIquid MEtal Reactor) by seismic analyses, investigate the design feasibility, and find the critical points of KALIMER reactor structures. The work scopes performed in this study are 1) the establishment of seismic design basis, 2) the development of seismic analysis model of KALIMER, 3) the modal analysis, 4) seismic time history analysis, 5) the evaluations of seismic isolation performance and seismic design margins, and 6) the evaluation of seismic capability of KALIMER. The horizontal fundamental frequency of KALIMER reactor structure is 8 Hz, which is far remote from the seismic isolation frequency, 0.7 Hz. The vertical first and second natural frequencies are about 2 Hz and 8 Hz respectively. These vertical natural frequencies are in a dominant ground motion frequency bands, therefore these modes will result in large vertical response amplifications. From the results of seismic time history analyses, the horizontal isolation performance is great but the large vertical amplifications are occurred in reactor structures. The RV Liner has the smallest seismic design margin as 0.18. From the results of seismic design margins evaluation, the critical design change are needed in the support barrel, separation plate, and baffle plate points. The seismic capability of KALIMER is about 0.35g. This value can be increased by the design changes of the separation plate and etc.. 11 tabs., 29 figs., 7 refs. (Author) .new

  10. Multivariate Formation Pressure Prediction with Seismic-derived Petrophysical Properties from Prestack AVO inversion and Poststack Seismic Motion Inversion

    Science.gov (United States)

    Yu, H.; Gu, H.

    2017-12-01

    A novel multivariate seismic formation pressure prediction methodology is presented, which incorporates high-resolution seismic velocity data from prestack AVO inversion, and petrophysical data (porosity and shale volume) derived from poststack seismic motion inversion. In contrast to traditional seismic formation prediction methods, the proposed methodology is based on a multivariate pressure prediction model and utilizes a trace-by-trace multivariate regression analysis on seismic-derived petrophysical properties to calibrate model parameters in order to make accurate predictions with higher resolution in both vertical and lateral directions. With prestack time migration velocity as initial velocity model, an AVO inversion was first applied to prestack dataset to obtain high-resolution seismic velocity with higher frequency that is to be used as the velocity input for seismic pressure prediction, and the density dataset to calculate accurate Overburden Pressure (OBP). Seismic Motion Inversion (SMI) is an inversion technique based on Markov Chain Monte Carlo simulation. Both structural variability and similarity of seismic waveform are used to incorporate well log data to characterize the variability of the property to be obtained. In this research, porosity and shale volume are first interpreted on well logs, and then combined with poststack seismic data using SMI to build porosity and shale volume datasets for seismic pressure prediction. A multivariate effective stress model is used to convert velocity, porosity and shale volume datasets to effective stress. After a thorough study of the regional stratigraphic and sedimentary characteristics, a regional normally compacted interval model is built, and then the coefficients in the multivariate prediction model are determined in a trace-by-trace multivariate regression analysis on the petrophysical data. The coefficients are used to convert velocity, porosity and shale volume datasets to effective stress and then

  11. Audio-based, unsupervised machine learning reveals cyclic changes in earthquake mechanisms in the Geysers geothermal field, California

    Science.gov (United States)

    Holtzman, B. K.; Paté, A.; Paisley, J.; Waldhauser, F.; Repetto, D.; Boschi, L.

    2017-12-01

    The earthquake process reflects complex interactions of stress, fracture and frictional properties. New machine learning methods reveal patterns in time-dependent spectral properties of seismic signals and enable identification of changes in faulting processes. Our methods are based closely on those developed for music information retrieval and voice recognition, using the spectrogram instead of the waveform directly. Unsupervised learning involves identification of patterns based on differences among signals without any additional information provided to the algorithm. Clustering of 46,000 earthquakes of $0.3

  12. Seismic Search Engine: A distributed database for mining large scale seismic data

    Science.gov (United States)

    Liu, Y.; Vaidya, S.; Kuzma, H. A.

    2009-12-01

    The International Monitoring System (IMS) of the CTBTO collects terabytes worth of seismic measurements from many receiver stations situated around the earth with the goal of detecting underground nuclear testing events and distinguishing them from other benign, but more common events such as earthquakes and mine blasts. The International Data Center (IDC) processes and analyzes these measurements, as they are collected by the IMS, to summarize event detections in daily bulletins. Thereafter, the data measurements are archived into a large format database. Our proposed Seismic Search Engine (SSE) will facilitate a framework for data exploration of the seismic database as well as the development of seismic data mining algorithms. Analogous to GenBank, the annotated genetic sequence database maintained by NIH, through SSE, we intend to provide public access to seismic data and a set of processing and analysis tools, along with community-generated annotations and statistical models to help interpret the data. SSE will implement queries as user-defined functions composed from standard tools and models. Each query is compiled and executed over the database internally before reporting results back to the user. Since queries are expressed with standard tools and models, users can easily reproduce published results within this framework for peer-review and making metric comparisons. As an illustration, an example query is “what are the best receiver stations in East Asia for detecting events in the Middle East?” Evaluating this query involves listing all receiver stations in East Asia, characterizing known seismic events in that region, and constructing a profile for each receiver station to determine how effective its measurements are at predicting each event. The results of this query can be used to help prioritize how data is collected, identify defective instruments, and guide future sensor placements.

  13. Seismic monitoring of an Underground Repository in Salt - Results of the measurements at the Gorleben Exploratory mine

    International Nuclear Information System (INIS)

    Altmann, Jurgen

    2013-01-01

    We have measured seismic and acoustic signals from various mining activities in the Gorleben exploratory mine in Germany, underground at -840 m and at the surface, tasked by the German Support Programme to the IAEA, in order to provide basic knowledge on the detectability of undeclared activities. During 7 weeks total nearly all sources of sound and vibration available in the mine were covered, with sensors at several positions and sources at several sites, sometimes with background signals from on-going exploration elsewhere. The peak-to-peak values of vibration velocity, referred to 100 m distance, range from tenths of micro metres/second for a hand-held chain saw via few μm/s to tens of μm/s for other tools such as picking, for vehicles, drilling and sledge-hammer blows. A grader with compactor plates produces hundreds, and a blast shot around one hundred thousand μm/s. The last two sources could be detected at the surface, too, at about 1.1 km slant distance; blasts were even seen at 5-6 km distance. The signal strengths vary by a factor 2 to 5 for similar conditions. Fitted by a power law, the decrease with distance is with an exponent mostly between -2 and -1. Spectra of seismic signals from periodic sources (such as percussion drilling or vehicle engines) show harmonic series. Rock removal, e.g. by drilling, produces broad-band excitation up to several kilohertz. Acoustic-seismic coupling is relevant. Monitoring could be done with an underground geophone “fence” around the repository, e.g. 500 m from the salt-dome margin and possibly in the salt 1 km off the repository. With that excavation by drilling and blasting could be detected by a simple amplitude criterion. Under which conditions excavation by tunnel boring machine or road header machine and other weaker activities could be detected needs to be studied.

  14. Dominant seismic sources for the cities in South Sumatra

    Science.gov (United States)

    Sunardi, Bambang; Sakya, Andi Eka; Masturyono, Murjaya, Jaya; Rohadi, Supriyanto; Sulastri, Putra, Ade Surya

    2017-07-01

    Subduction zone along west of Sumatra and Sumatran fault zone are active seismic sources. Seismotectonically, South Sumatra could be affected by earthquakes triggered by these seismic sources. This paper discussed contribution of each seismic source to earthquake hazards for cities of Palembang, Prabumulih, Banyuasin, OganIlir, Ogan Komering Ilir, South Oku, Musi Rawas and Empat Lawang. These hazards are presented in form of seismic hazard curves. The study was conducted by using Probabilistic Seismic Hazard Analysis (PSHA) of 2% probability of exceedance in 50 years. Seismic sources used in analysis included megathrust zone M2 of Sumatra and South Sumatra, background seismic sources and shallow crustal seismic sources consist of Ketaun, Musi, Manna and Kumering faults. The results of the study showed that for cities relatively far from the seismic sources, subduction / megathrust seismic source with a depth ≤ 50 km greatly contributed to the seismic hazard and the other areas showed deep background seismic sources with a depth of more than 100 km dominate to seismic hazard respectively.

  15. Seismic analysis for the ALMR

    International Nuclear Information System (INIS)

    Tajirian, F.F.

    1992-01-01

    The Advanced Liquid Metal Reactor (ALMR) design uses seismic isolation as a cost effective approach for simplifying seismic design of the reactor module, and for enhancing margins to handle beyond design basis earthquakes (BDBE). A comprehensive seismic analysis plan has been developed to confirm the adequacy of the design and to support regulatory licensing activities. In this plan state-of-the-art computer programs are used to evaluate the system response of the ALMR. Several factors that affect seismic response will be investigated. These include variability in the input earthquake mechanism, soil-structure interaction effects, and nonlinear response of the isolators. This paper reviews the type of analyses that are planned, and discuses the approach that will be used for validating the specific features of computer programs that are required in the analysis of isolated structures. To date, different linear and nonlinear seismic analyses have been completed. The results of recently completed linear analyses have been summarized elsewhere. The findings of three-dimensional seismic nonlinear analyses are presented in this paper. These analyses were performed to evaluate the effect of changes of isolator horizontal stiffness with horizontal displacement on overall response, to develop an approach for representing BDBE events with return periods exceeding 10,000 years, and to assess margins in the design for BDBEs. From the results of these analyses and bearing test data, it can be concluded that a properly designed and constructed seismic isolation system can accommodate displacements several times the design safe shutdown earthquake (SSE) for the ALMR. (author)

  16. Seismicity and tectonics of Bangladesh

    International Nuclear Information System (INIS)

    Hossain, K.M.

    1989-05-01

    Northern and eastern Bangladesh and surrounding areas belong to a seismically active zone and are associated with the subduction of the Indian plate. The seismicity and tectonics have been studied in detail and the observations have been correlated to understand the earthquake phenomenon in the region. The morphotectonic behaviour of northern Bangladesh shows that it is deeply related to the movement of the Dauki fault system and relative upliftment of the Shillong plateau. Contemporary seismicity in the Dauki fault system is relatively quiet comparing to that in the Naga-Disang-Haflong thrust belt giving rise to the probability of sudden release of energy being accumulated in the vicinity of the Dauki fault system. This observation corresponds with the predicted average return period of a large earthquake (1897 type) and the possibility of M > 8 earthquake in the vicinity of the Dauki fault within this century should not be ruled out. The seismicity in the folded belt in the east follows the general trend of Arakan-Yoma anticlinorium and represents shallow and low-angled thrust movements in conformity with the field observation. Seismotectonic behaviour in the deep basin part of Bangladesh demonstrates that an intraplate movement in the basement rock has been taking place along the deep-seated faults causing relative upliftment and subsidence in the basin. Bangladesh has been divided into three seismic zones on the basis of morphotectonic and seismic behaviour. Zone-I has been identified as the zone of high seismic risk. (author). 43 refs, 5 figs, 3 tabs

  17. Seismicity, state of stress and induced seismicity in the molasse basin and Jura (N-Switzerland)

    Energy Technology Data Exchange (ETDEWEB)

    Deichmann, N. [Schweizerischer Erdbebendienst, ETH Zuerich, Zuerich (Switzerland); Burlini, L. [Institut of Geology, ETH Zuerich, Zuerich (Switzerland)

    2010-07-01

    This illustrated report for the Swiss Federal Office of Energy (SFOE) is one of a series of appendices dealing with the potential for geological sequestration of CO{sub 2} in Switzerland. This report takes a look at the seismicity, state of stress and induced seismicity in the molasse basin and Jura Mountains in northern Switzerland. Data collected since 1983 by the Swiss Earthquake Service and the National Cooperative for the Disposal of Radioactive Wastes NAGRA on the tectonics and seismic properties of North-western Switzerland is noted. The results are illustrated with a number of maps and graphical representations and are discussed in detail. Cases of induced seismicity as resulting from both natural and man-made causes are examined.

  18. Seismic Isolation Working Meeting Gap Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sabharwall, Piyush [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    The ultimate goal in nuclear facility and nuclear power plant operations is operating safety during normal operations and maintaining core cooling capabilities during off-normal events including external hazards. Understanding the impact external hazards, such as flooding and earthquakes, have on nuclear facilities and NPPs is critical to deciding how to manage these hazards to expectable levels of risk. From a seismic risk perspective the goal is to manage seismic risk. Seismic risk is determined by convolving the seismic hazard with seismic fragilities (capacity of systems, structures, and components (SSCs)). There are large uncertainties associated with evolving nature of the seismic hazard curves. Additionally there are requirements within DOE and potential requirements within NRC to reconsider updated seismic hazard curves every 10 years. Therefore opportunity exists for engineered solutions to manage this seismic uncertainty. One engineered solution is seismic isolation. Current seismic isolation (SI) designs (used in commercial industry) reduce horizontal earthquake loads and protect critical infrastructure from the potentially destructive effects of large earthquakes. The benefit of SI application in the nuclear industry is being recognized and SI systems have been proposed, in the American Society of Civil Engineers (ASCE) 4 standard, to be released in 2014, for Light Water Reactors (LWR) facilities using commercially available technology. However, there is a lack of industry application to the nuclear industry and uncertainty with implementing the procedures outlined in ASCE-4. Opportunity exists to determine barriers associated with implementation of current ASCE-4 standard language.

  19. The New Italian Seismic Hazard Model

    Science.gov (United States)

    Marzocchi, W.; Meletti, C.; Albarello, D.; D'Amico, V.; Luzi, L.; Martinelli, F.; Pace, B.; Pignone, M.; Rovida, A.; Visini, F.

    2017-12-01

    In 2015 the Seismic Hazard Center (Centro Pericolosità Sismica - CPS) of the National Institute of Geophysics and Volcanology was commissioned of coordinating the national scientific community with the aim to elaborate a new reference seismic hazard model, mainly finalized to the update of seismic code. The CPS designed a roadmap for releasing within three years a significantly renewed PSHA model, with regard both to the updated input elements and to the strategies to be followed. The main requirements of the model were discussed in meetings with the experts on earthquake engineering that then will participate to the revision of the building code. The activities were organized in 6 tasks: program coordination, input data, seismicity models, ground motion predictive equations (GMPEs), computation and rendering, testing. The input data task has been selecting the most updated information about seismicity (historical and instrumental), seismogenic faults, and deformation (both from seismicity and geodetic data). The seismicity models have been elaborating in terms of classic source areas, fault sources and gridded seismicity based on different approaches. The GMPEs task has selected the most recent models accounting for their tectonic suitability and forecasting performance. The testing phase has been planned to design statistical procedures to test with the available data the whole seismic hazard models, and single components such as the seismicity models and the GMPEs. In this talk we show some preliminary results, summarize the overall strategy for building the new Italian PSHA model, and discuss in detail important novelties that we put forward. Specifically, we adopt a new formal probabilistic framework to interpret the outcomes of the model and to test it meaningfully; this requires a proper definition and characterization of both aleatory variability and epistemic uncertainty that we accomplish through an ensemble modeling strategy. We use a weighting scheme

  20. Fluid injection and induced seismicity

    Science.gov (United States)

    Kendall, Michael; Verdon, James

    2016-04-01

    The link between fluid injection, or extraction, and induced seismicity has been observed in reservoirs for many decades. In fact spatial mapping of low magnitude events is routinely used to estimate a stimulated reservoir volume. However, the link between subsurface fluid injection and larger felt seismicity is less clear and has attracted recent interest with a dramatic increase in earthquakes associated with the disposal of oilfield waste fluids. In a few cases, hydraulic fracturing has also been linked to induced seismicity. Much can be learned from past case-studies of induced seismicity so that we can better understand the risks posed. Here we examine 12 case examples and consider in particular controls on maximum event size, lateral event distributions, and event depths. Our results suggest that injection volume is a better control on maximum magnitude than past, natural seismicity in a region. This might, however, simply reflect the lack of baseline monitoring and/or long-term seismic records in certain regions. To address this in the UK, the British Geological Survey is leading the deployment of monitoring arrays in prospective shale gas areas in Lancashire and Yorkshire. In most cases, seismicity is generally located in close vicinity to the injection site. However, in some cases, the nearest events are up to 5km from the injection point. This gives an indication of the minimum radius of influence of such fluid injection projects. The most distant events are never more than 20km from the injection point, perhaps implying a maximum radius of influence. Some events are located in the target reservoir, but most occur below the injection depth. In fact, most events lie in the crystalline basement underlying the sedimentary rocks. This suggests that induced seismicity may not pose a leakage risk for fluid migration back to the surface, as it does not impact caprock integrity. A useful application for microseismic data is to try and forecast induced seismicity

  1. Seismic Structure of Southern African Cratons

    DEFF Research Database (Denmark)

    Soliman, Mohammad Youssof Ahmad; Artemieva, Irina; Levander, Alan

    2014-01-01

    functions and finite-frequency tomography based on data from the South Africa Seismic Experiment (SASE). Combining the two methods provides high vertical and lateral resolution. The main results obtained are (1) the presence of a highly heterogeneous crustal structure, in terms of thickness, composition (as......Cratons are extremely stable continental crustal areas above thick depleted lithosphere. These regions have remained largely unchanged for more than 2.5 Ga. This study presents a new seismic model of the seismic structure of the crust and lithospheric mantle constrained by seismic receiver...

  2. Toe-of-slope of a Cretaceous carbonate platform in outcrop, seismic model and offshore seismic data (Apulia, Italy)

    Science.gov (United States)

    Bracco Gartner, Guido; Morsilli, Michele; Schlager, Wolfgang; Bosellini, Alfonso

    Synthetic seismic models of outcrops in the Early Cretaceous slope of a carbonate platform on the Gargano Promontory (southern Italy) were compared to an offshore seismic section south of the Promontory. Outcrops of the same age on the promontory have the same sequence stratigraphic characteristics as their offshore equivalent, and are the only areas where the transition from platform to basin of Early Cretaceous is exposed on land. Two adjacent outcrop areas were combined into one seismic-scale lithologic model with the aid of photo mosaics, measured sections, and biostratigraphic data. Velocity, density, and porosity measurements on spot samples were used to construct the impedance model. Seismic models were generated by vertical incidence and finite difference programs. The results indicate that the reflections in the seismic model are controlled by the impedance contrast between low porous intervals rich in debris from the platform and highly porous intervals of pelagic lime mudstone, nearly devoid of debris. Finite difference seismic display showed best resemblance with the real seismic data, especially by mapping a drowning unconformity.

  3. Eastern US seismic hazard characterization update

    International Nuclear Information System (INIS)

    Savy, J.B.; Boissonnade, A.C.; Mensing, R.W.; Short, C.M.

    1993-06-01

    In January 1989, LLNL published the results of a multi-year project, funded by NRC, on estimating seismic hazard at nuclear plant sites east of the Rockies. The goal of this study was twofold: to develop a good central estimate (median) of the seismic hazard and to characterize the uncertainty in the estimates of this hazard. In 1989, LLNL was asked by DOE to develop site specific estimates of the seismic hazard at the Savannah River Site (SRS) in South Carolina as part of the New Production Reactor (NPR) project. For the purpose of the NPR, a complete review of the methodology and of the data acquisition process was performed. Work done under the NPR project has shown that first order improvement in the estimates of the uncertainty (i.e., lower mean hazard values) could be easily achieved by updating the modeling of the seismicity and ground motion attenuation uncertainty. To this effect, NRC sponsored LLNL to perform a reelicitation to update the seismicity and ground motion experts' inputs and to revise methods to combine seismicity and ground motion inputs in the seismic hazard analysis for nuclear power plant sites east of the Rocky Mountains. The objective of the recent study was to include the first order improvements that reflect the latest knowledge in seismicity and ground motion modeling and produce an update of all the hazard results produced in the 1989 study. In particular, it had been demonstrated that eliciting seismicity information in terms of rates of earthquakes rather than a- and b-values, and changing the elicitation format to a one-on-one interview, improved our ability to express the uncertainty of earthquake rates of occurrence at large magnitudes. Thus, NRC sponsored this update study to refine the model of uncertainty, and to re-elicitate of the experts' interpretations of the zonation and seismicity, as well as to reelicitate the ground motion models, based on current state of knowledge

  4. Seismic margins and calibration of piping systems

    International Nuclear Information System (INIS)

    Shieh, L.C.; Tsai, N.C.; Yang, M.S.; Wong, W.L.

    1985-01-01

    The Seismic Safety Margins Research Program (SSMRP) is a US Nuclear Regulatory Commission-funded, multiyear program conducted by Lawrence Livermore National Laboratory (LLNL). Its objective is to develop a complete, fully coupled analysis procedure for estimating the risk of earthquake-induced radioactive release from a commercial nuclear power plant and to determine major contributors to the state-of-the-art seismic and systems analysis process and explicitly includes the uncertainties in such a process. The results will be used to improve seismic licensing requirements for nuclear power plants. In Phase I of SSMRP, the overall seismic risk assessment methodology was developed and assembled. The application of this methodology to the seismic PRA (Probabilistic Risk Assessment) at the Zion Nuclear Power Plant has been documented. This report documents the method deriving response factors. The response factors, which relate design calculated responses to best estimate values, were used in the seismic response determination of piping systems for a simplified seismic probablistic risk assessment. 13 references, 31 figures, 25 tables

  5. Input for seismic hazard assessment using Vrancea seismic source region

    International Nuclear Information System (INIS)

    Ivan, Iren-Adelina; Enescu, B.D.; Pantea, A.

    1998-01-01

    We use an extended and combined data base including historical and modern, qualitative and quantitative data, i.e., more than 25 events during the period 1790 - 1990 with epicentral/maximum intensities ranging from X to V degree (MSK scale), the variation interval of isoseismal curves ranging from IX th to III rd degree. The data set was analysed using both the sum phasor techniques of Ridelek and Sacks (1984) for different magnitudes and depth intervals and the Stepp's method. For the assessment of seismic hazard we need a pattern of seismic source regions including an estimation for the maximum expected magnitude and the return period for the studied regions. Another necessary step in seismic hazard assessment is to develop attenuation relationships specific to a seismogenic zone, particularly to sub-crustal earthquakes of Vrancea region. The conceptual frame involves the use of appropriate decay models and consideration of the randomness in the attenuation, taking into account the azimuthal variation of the isoseist shapes. (authors)

  6. Nonlinear seismic analysis of a large sodium pump

    International Nuclear Information System (INIS)

    Huang, S.N.

    1985-01-01

    The bearings and seismic bumpers used in a large sodium pump of a typical breeder reactor plant may need to be characterized by nonlinear springs and gaps. Then, nonlinear seismic analysis utilizing the time-history method is an effective way to predict the pump behaviors during seismic events, especially at those bearing and seismic bumper areas. In this study, synthesized time histories were developed based on specified seismic response spectra. A nonlinear seismic analysis was then conducted and results were compared with those obtained by linear seismic analysis using the response spectrum method. In contrast to some previous nonlinear analysis trends, the bearing impact forces predicted by nonlinear analysis were higher than those obtained by the response spectrum method. This might be due to the larger gaps and stiffer bearing supports used in this specific pump. However, at locations distant from the impact source, the nonlinear seismic analysis has predicted slightly less responses than those obtained by linear seismic analysis. The seismically induced bearing impact forces were used to study the friction induced thermal stresses on the hydrostatic bearing and to predict the coastdown time of the pump. Results and discussions are presented

  7. Nonlinear seismic analysis of a large sodium pump

    International Nuclear Information System (INIS)

    Huang, S.N.

    1985-01-01

    The bearings and seismic bumpers used in a large sodium pump of a typical breeder reactor plant may need to be characterized by nonlinear springs and gaps. Then, nonlinear seismic analysis utilizing the time-history method is an effective way to predict the pump behaviors during seismic events - especially at those bearing and seismic bumper areas. In this study, synthesized time histories were developed based on specified seismic response spectra. A nonlinear seismic analysis was then conducted and results were compared with those obtained by linear seismic analysis using the response spectrum method. In contrast to some previous nonlinear analysis trends, the bearing impact forces predicted by nonlinear analysis were higher than those obtained by the response spectrum method. This might be due to the larger gaps and stiffer bearing supports used in this specific pump. However, at locations distant from the impact source, the nonlinear seismic analysis has predicted slightly less responses than those obtained by linear seismic analysis. The seismically induced bearing impact forces were used to study the friction induced thermal stresses on the hydrostatic bearing and to predict the coastdown time of the pump. Results and discussions are presented

  8. From Geodetic Imaging of Seismic and Aseismic Fault Slip to Dynamic Modeling of the Seismic Cycle

    Science.gov (United States)

    Avouac, Jean-Philippe

    2015-05-01

    Understanding the partitioning of seismic and aseismic fault slip is central to seismotectonics as it ultimately determines the seismic potential of faults. Thanks to advances in tectonic geodesy, it is now possible to develop kinematic models of the spatiotemporal evolution of slip over the seismic cycle and to determine the budget of seismic and aseismic slip. Studies of subduction zones and continental faults have shown that aseismic creep is common and sometimes prevalent within the seismogenic depth range. Interseismic coupling is generally observed to be spatially heterogeneous, defining locked patches of stress accumulation, to be released in future earthquakes or aseismic transients, surrounded by creeping areas. Clay-rich tectonites, high temperature, and elevated pore-fluid pressure seem to be key factors promoting aseismic creep. The generally logarithmic time evolution of afterslip is a distinctive feature of creeping faults that suggests a logarithmic dependency of fault friction on slip rate, as observed in laboratory friction experiments. Most faults can be considered to be paved with interlaced patches where the friction law is either rate-strengthening, inhibiting seismic rupture propagation, or rate-weakening, allowing for earthquake nucleation. The rate-weakening patches act as asperities on which stress builds up in the interseismic period; they might rupture collectively in a variety of ways. The pattern of interseismic coupling can help constrain the return period of the maximum- magnitude earthquake based on the requirement that seismic and aseismic slip sum to match long-term slip. Dynamic models of the seismic cycle based on this conceptual model can be tuned to reproduce geodetic and seismological observations. The promise and pitfalls of using such models to assess seismic hazard are discussed.

  9. Seismic design standardization of nuclear facilities

    International Nuclear Information System (INIS)

    Reddy, G.R.; Vaze, K.K.

    2011-01-01

    Full text: Structures, Systems and Components (SSCs) of Nuclear Facilities have to be designed for normal operating loads such as dead weight, pressure, temperature etc., and accidental loads such as earthquakes, floods, extreme, wind air craft impact, explosions etc. Man made accidents such as aircraft impact, explosions etc., some times may be considered as design basis event and some times taken care by providing administrative controls. This will not be possible in the case of natural events such as earthquakes, flooding, extreme winds etc. Among natural events earthquakes are considered as most devastating and need to be considered as design basis event. It is generally felt design of SSCs for earthquake loads is very time consuming and expensive. Conventional seismic design approaches demands for large number of supports for systems and components. This results in large space occupation and in turn creates difficulties for maintenance and in service inspection of systems and components. In addition, complete exercise of design need to be repeated for plants being located at different sites due to different seismic demands. However, advanced seismic response control methods will help to standardize the seismic design meeting the safety and economy. These methods adopt passive, semi active and active devices, and base isolators to control the seismic response. In nuclear industry, it is advisable to go for passive devices to control the seismic responses. Ideally speaking, these methods will make the designs made for normal loads can also satisfy the seismic demand without calling for change in material, geometry, layout etc. in the SSCs. This paper explain the basic ideas of seismic response control methods, demonstrate the effectiveness of control methods through case studies and eventually give the procedure to be adopted for seismic design standardization of nuclear facilities

  10. Seismic component fragility data base for IPEEE

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.

    1990-01-01

    Seismic probabilistic risk assessment or a seismic margin study will require a reliable data base of seismic fragility of various equipment classes. Brookhaven National Laboratory (BNL) has selected a group of equipment and generically evaluated the seismic fragility of each equipment class by use of existing test data. This paper briefly discusses the evaluation methodology and the fragility results. The fragility analysis results when used in the Individual Plant Examination for External Events (IPEEE) Program for nuclear power plants are expected to provide insights into seismic vulnerabilities of equipment for earthquakes beyond the design basis. 3 refs., 1 fig., 1 tab

  11. Machine terms dictionary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-04-15

    This book gives descriptions of machine terms which includes machine design, drawing, the method of machine, machine tools, machine materials, automobile, measuring and controlling, electricity, basic of electron, information technology, quality assurance, Auto CAD and FA terms and important formula of mechanical engineering.

  12. NSR&D Program Fiscal Year (FY) 2015 Call for Proposals Mitigation of Seismic Risk at Nuclear Facilities using Seismic Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-02-01

    Seismic isolation (SI) has the potential to drastically reduce seismic response of structures, systems, or components (SSCs) and therefore the risk associated with large seismic events (large seismic event could be defined as the design basis earthquake (DBE) and/or the beyond design basis earthquake (BDBE) depending on the site location). This would correspond to a potential increase in nuclear safety by minimizing the structural response and thus minimizing the risk of material release during large seismic events that have uncertainty associated with their magnitude and frequency. The national consensus standard America Society of Civil Engineers (ASCE) Standard 4, Seismic Analysis of Safety Related Nuclear Structures recently incorporated language and commentary for seismically isolating a large light water reactor or similar large nuclear structure. Some potential benefits of SI are: 1) substantially decoupling the SSC from the earthquake hazard thus decreasing risk of material release during large earthquakes, 2) cost savings for the facility and/or equipment, and 3) applicability to both nuclear (current and next generation) and high hazard non-nuclear facilities. Issue: To date no one has evaluated how the benefit of seismic risk reduction reduces cost to construct a nuclear facility. Objective: Use seismic probabilistic risk assessment (SPRA) to evaluate the reduction in seismic risk and estimate potential cost savings of seismic isolation of a generic nuclear facility. This project would leverage ongoing Idaho National Laboratory (INL) activities that are developing advanced (SPRA) methods using Nonlinear Soil-Structure Interaction (NLSSI) analysis. Technical Approach: The proposed study is intended to obtain an estimate on the reduction in seismic risk and construction cost that might be achieved by seismically isolating a nuclear facility. The nuclear facility is a representative pressurized water reactor building nuclear power plant (NPP) structure

  13. OGS improvements in 2012 in running the North-eastern Italy Seismic Network: the Ferrara VBB borehole seismic station

    Science.gov (United States)

    Pesaresi, D.; Romanelli, M.; Barnaba, C.; Bragato, P. L.; Durì, G.

    2014-07-01

    The Centro di Ricerche Sismologiche (CRS, Seismological Research Centre) of the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Italian National Institute for Oceanography and Experimental Geophysics) in Udine (Italy) after the strong earthquake of magnitude M=6.4 occurred in 1976 in the Italian Friuli-Venezia Giulia region, started to operate the North-eastern Italy Seismic Network: it currently consists of 17 very sensitive broad band and 18 simpler short period seismic stations, all telemetered to and acquired in real time at the OGS-CRS data centre in Udine. Real time data exchange agreements in place with other Italian, Slovenian, Austrian and Swiss seismological institutes lead to a total number of about 100 seismic stations acquired in real time, which makes the OGS the reference institute for seismic monitoring of North-eastern Italy. The south-western edge of the OGS seismic network (Fig. 1) stands on the Po alluvial basin: earthquake localization and characterization in this area is affected by the presence of soft alluvial deposits. OGS ha already experience in running a local seismic network in high noise conditions making use of borehole installations in the case of the micro-seismicity monitoring of a local gas storage site for a private company. Following the ML = 5.9 earthquake that struck the Emilia region around Ferrara in Northern Italy on 20 May 2012 at 02:03:53 UTC, a cooperation of Istituto Nazionale di Geofisica e Vulcanologia, OGS, the Comune di Ferrara and the University of Ferrara lead to the reinstallation of a previously existing very broad band (VBB) borehole seismic station in Ferrara. The aim of the OGS intervention was on one hand to extend its real time seismic monitoring capabilities toward South-West, including Ferrara and its surroundings, and on the other hand to evaluate the seismic response at the site. We will describe improvements in running the North-eastern Italy Seismic Network, including details of

  14. Application of the neo-deterministic seismic microzonation procedure in Bulgaria and validation of the seismic input against Eurocode 8

    International Nuclear Information System (INIS)

    Paskaleva, I.; Kouteva, M.; Vaccari, F.; Panza, G.F.

    2008-03-01

    The earthquake record and the Code for design and construction in seismic regions in Bulgaria have shown that the territory of the Republic of Bulgaria is exposed to a high seismic risk due to local shallow and regional strong intermediate-depth seismic sources. The available strong motion database is quite limited, and therefore not representative at all of the real hazard. The application of the neo-deterministic seismic hazard assessment procedure for two main Bulgarian cities has been capable to supply a significant database of synthetic strong motions for the target sites, applicable for earthquake engineering purposes. The main advantage of the applied deterministic procedure is the possibility to take simultaneously and correctly into consideration the contribution to the earthquake ground motion at the target sites of the seismic source and of the seismic wave propagation in the crossed media. We discuss in this study the result of some recent applications of the neo-deterministic seismic microzonation procedure to the cities of Sofia and Russe. The validation of the theoretically modeled seismic input against Eurocode 8 and the few available records at these sites is discussed. (author)

  15. Systems considerations in seismic margin evaluations

    International Nuclear Information System (INIS)

    Buttermer, D.R.

    1987-01-01

    Increasing knowledge in the geoscience field has led to the understanding that, although highly unlikely, it is possible for a nuclear power plant to be subjected to earthquake ground motion greater than that for which the plant was designed. While it is recognized that there are conservatisms inherent in current design practices, interest has developed in evaluating the seismic risk of operating plants. Several plant-specific seismic probabilistic risk assessments (SPRA) have been completed to address questions related to the seismic risk of a plant. The results from such SPRAs are quite informative, but such studies may entail a considerable amount of expensive analysis of large portions of the plant. As an alternative to an SPRA, it may be more practical to select an earthquake level above the design basis for which plant survivability is to be demonstrated. The principal question to be addressed in a seismic margin evaluation is: At what ground motion levels does one have a high confidence that the probability of seismically induced core damage is sufficiently low? In a seismic margin evaluation, an earthquake level is selected (based on site-specific geoscience considerations) for which a stable, long-term safe shutdown condition is to be demonstrated. This prespecified earthquake level is commonly referred to as the seismic margin earthquake (SME). The Electric Power Research Institute is currently supporting a research project to develop procedures for use by the utilities to allow them to perform nuclear plant seismic margin evaluations. This paper describes the systems-related aspects of these procedures

  16. Romanian Educational Seismic Network Project

    Science.gov (United States)

    Tataru, Dragos; Ionescu, Constantin; Zaharia, Bogdan; Grecu, Bogdan; Tibu, Speranta; Popa, Mihaela; Borleanu, Felix; Toma, Dragos; Brisan, Nicoleta; Georgescu, Emil-Sever; Dobre, Daniela; Dragomir, Claudiu-Sorin

    2013-04-01

    Romania is one of the most active seismic countries in Europe, with more than 500 earthquakes occurring every year. The seismic hazard of Romania is relatively high and thus understanding the earthquake phenomena and their effects at the earth surface represents an important step toward the education of population in earthquake affected regions of the country and aims to raise the awareness about the earthquake risk and possible mitigation actions. In this direction, the first national educational project in the field of seismology has recently started in Romania: the ROmanian EDUcational SEISmic NETwork (ROEDUSEIS-NET) project. It involves four partners: the National Institute for Earth Physics as coordinator, the National Institute for Research and Development in Construction, Urban Planning and Sustainable Spatial Development " URBAN - INCERC" Bucharest, the Babeş-Bolyai University (Faculty of Environmental Sciences and Engineering) and the software firm "BETA Software". The project has many educational, scientific and social goals. The main educational objectives are: training students and teachers in the analysis and interpretation of seismological data, preparing of several comprehensive educational materials, designing and testing didactic activities using informatics and web-oriented tools. The scientific objective is to introduce into schools the use of advanced instruments and experimental methods that are usually restricted to research laboratories, with the main product being the creation of an earthquake waveform archive. Thus a large amount of such data will be used by students and teachers for educational purposes. For the social objectives, the project represents an effective instrument for informing and creating an awareness of the seismic risk, for experimentation into the efficacy of scientific communication, and for an increase in the direct involvement of schools and the general public. A network of nine seismic stations with SEP seismometers

  17. The Global Detection Capability of the IMS Seismic Network in 2013 Inferred from Ambient Seismic Noise Measurements

    Science.gov (United States)

    Gaebler, P. J.; Ceranna, L.

    2016-12-01

    All nuclear explosions - on the Earth's surface, underground, underwater or in the atmosphere - are banned by the Comprehensive Nuclear-Test-Ban Treaty (CTBT). As part of this treaty, a verification regime was put into place to detect, locate and characterize nuclear explosion testings at any time, by anyone and everywhere on the Earth. The International Monitoring System (IMS) plays a key role in the verification regime of the CTBT. Out of the different monitoring techniques used in the IMS, the seismic waveform approach is the most effective technology for monitoring nuclear underground testing and to identify and characterize potential nuclear events. This study introduces a method of seismic threshold monitoring to assess an upper magnitude limit of a potential seismic event in a certain given geographical region. The method is based on ambient seismic background noise measurements at the individual IMS seismic stations as well as on global distance correction terms for body wave magnitudes, which are calculated using the seismic reflectivity method. From our investigations we conclude that a global detection threshold of around mb 4.0 can be achieved using only stations from the primary seismic network, a clear latitudinal dependence for the detection thresholdcan be observed between northern and southern hemisphere. Including the seismic stations being part of the auxiliary seismic IMS network results in a slight improvement of global detection capability. However, including wave arrivals from distances greater than 120 degrees, mainly PKP-wave arrivals, leads to a significant improvement in average global detection capability. In special this leads to an improvement of the detection threshold on the southern hemisphere. We further investigate the dependence of the detection capability on spatial (latitude and longitude) and temporal (time) parameters, as well as on parameters such as source type and percentage of operational IMS stations.

  18. Romanian seismic network

    International Nuclear Information System (INIS)

    Ionescu, Constantin; Rizescu, Mihaela; Popa, Mihaela; Grigore, Adrian

    2000-01-01

    The research in the field of seismology in Romania is mainly carried out by the National Institute for Earth Physics (NIEP). The NIEP activities are mainly concerned with the fundamental research financed by research contracts from public sources and the maintenance and operation of the Romanian seismic network. A three stage seismic network is now operating under NIEP, designed mainly to monitor the Vrancea seismic region in a magnitude range from microearthquakes to strong events: - network of 18 short-period seismometers (S13); - Teledyne Geotech Instruments (Texas); - network of 7 stations with local digital recording (PCM-5000) on magnetic tape, made up of, S13 geophone (T=2 s) on vertical component and SH1 geophone (T=5 s) on horizontal components; - network of 28 SMA-1 accelerometers and 30 digital accelerometers (Kinemetrics - K2) installed in the free field conditions in the framework of the joint German-Romanian cooperation program (CRC); the K2 instruments cover a magnitude range from 1.4 to 8.0. Since 1994, MLR (Muntele Rosu) station has become part of the GEOFON network and was provided with high performance broad band instruments. At Bucharest and Timisoara data centers, an automated and networked seismological system performs the on-line digital acquisition and processing of the telemetered data. Automatic processing includes discrimination between local and distant seismic events, earthquake location and magnitude computation, and source parameter determination for local earthquakes. The results are rapidly distributed via Internet, to several seismological services in Europe and USA, to be used in the association/confirmation procedures. Plans for new developments of the network include the upgrade from analog to digital telemetry and new stations for monitoring local seismicity. (authors)

  19. Continuous recording of seismic signals in Alpine permafrost

    Science.gov (United States)

    Hausmann, H.; Krainer, K.; Staudinger, M.; Brückl, E.

    2009-04-01

    Over the past years various geophysical methods were applied to study the internal structure and the temporal variation of permafrost whereof seismic is of importance. For most seismic investigations in Alpine permafrost 24-channel equipment in combination with long data and trigger cables is used. Due to the harsh environment source and geophone layouts are often limited to 2D profiles. With prospect for future 3D-layouts we introduce an alternative of seismic equipment that can be used for several applications in Alpine permafrost. This study is focussed on controlled and natural source seismic experiments in Alpine permafrost using continuous data recording. With recent data from an ongoing project ("Permafrost in Austria") we will highlight the potential of the used seismic equipment for three applications: (a) seismic permafrost mapping of unconsolidated sediments, (b) seismic tomography in rock mass, and (c) passive seismic monitoring of rock falls. Single recording units (REFTEK 130, 6 channels) are used to continuously record the waveforms of both the seismic signals and a trigger signal. The combination of a small number of recording units with different types of geophones or a trigger allow numerous applications in Alpine permafrost with regard to a high efficiency and flexible seismic layouts (2D, 3D, 4D). The efficiency of the light and robust seismic equipment is achieved by the simple acquisition and the flexible and fast deployment of the (omni-directional) geophones. Further advantages are short (data and trigger) cables and the prevention of trigger errors. The processing of the data is aided by 'Seismon' which is an open source software project based on Matlab® and MySQL (see SM1.0). For active-source experiments automatic stacking of the seismic signals is implemented. For passive data a program for automatic detection of events (e.g. rock falls) is available which allows event localization. In summer 2008 the seismic equipment was used for the

  20. Some relations between quantum Turing machines and Turing machines

    OpenAIRE

    Sicard, Andrés; Vélez, Mario

    1999-01-01

    For quantum Turing machines we present three elements: Its components, its time evolution operator and its local transition function. The components are related with the components of deterministic Turing machines, the time evolution operator is related with the evolution of reversible Turing machines and the local transition function is related with the transition function of probabilistic and reversible Turing machines.

  1. Seismic risk assessment and application in the central United States

    Science.gov (United States)

    Wang, Z.

    2011-01-01

    Seismic risk is a somewhat subjective, but important, concept in earthquake engineering and other related decision-making. Another important concept that is closely related to seismic risk is seismic hazard. Although seismic hazard and seismic risk have often been used interchangeably, they are fundamentally different: seismic hazard describes the natural phenomenon or physical property of an earthquake, whereas seismic risk describes the probability of loss or damage that could be caused by a seismic hazard. The distinction between seismic hazard and seismic risk is of practical significance because measures for seismic hazard mitigation may differ from those for seismic risk reduction. Seismic risk assessment is a complicated process and starts with seismic hazard assessment. Although probabilistic seismic hazard analysis (PSHA) is the most widely used method for seismic hazard assessment, recent studies have found that PSHA is not scientifically valid. Use of PSHA will lead to (1) artifact estimates of seismic risk, (2) misleading use of the annual probability of exccedance (i.e., the probability of exceedance in one year) as a frequency (per year), and (3) numerical creation of extremely high ground motion. An alternative approach, which is similar to those used for flood and wind hazard assessments, has been proposed. ?? 2011 ASCE.

  2. Seismic qualification of a commercial grade emergency diesel generator system in high seismic zones

    International Nuclear Information System (INIS)

    Khan, Mohsin R.; Chen, Wayne W.H.; Chu, Winnie S.

    2004-01-01

    The paper presents the seismic qualification of a commercially procured emergency diesel generator (EDG) system for use in a nuclear power plant. Response spectrum analyses of finite element models, validated using in situ vibration test data, were performed to qualify the skid and floor mounted mechanical components whose functional capacity and structural integrity can be analyzed. Time history analyses of these models were also performed to obtain the amplified response spectra for seismic testing of small valves, electrical and electro-mechanical components whose functional capacity can not be analyzed to establish the seismic qualification. The operational loads were obtained by in-plant vibration monitoring. Full scale shake table testing was performed for auxiliary electrical cabinets. It is concluded that with some minor structural modifications, a commercial grade EDG system can be qualified for safety-related applications in nuclear power plants located in high seismic zones. (author)

  3. Analysis of EAST tokamak cryostat anti-seismic performance

    International Nuclear Information System (INIS)

    Chen Wei; Kong Xiaoling; Liu Sumei; Ni Xiaojun; Wang Zhongwei

    2014-01-01

    A 3-D finite element model for EAST tokamak cryostat is established by using ANSYS. On the basis of the modal analysis, the seismic response of the EAST tokamak cryostat structure is calculated according to an input of the design seismic response spectrum referring to code for seismic design of nuclear power plants. Calculation results show that EAST cryostat displacement and stress response is small under the action of earthquake. According to the standards, EAST tokamak cryostat structure under the action of design seismic can meet the requirements of anti-seismic design intensity, and ensure the anti-seismic safety of equipment. (authors)

  4. Seismic signal and noise on Europa

    Science.gov (United States)

    Panning, Mark; Stähler, Simon; Bills, Bruce; Castillo Castellanos, Jorge; Huang, Hsin-Hua; Husker, Allen; Kedar, Sharon; Lorenz, Ralph; Pike, William T.; Schmerr, Nicholas; Tsai, Victor; Vance, Steven

    2017-10-01

    Seismology is one of our best tools for detailing interior structure of planetary bodies, and a seismometer is included in the baseline and threshold mission design for the upcoming Europa Lander mission. Guiding mission design and planning for adequate science return, though, requires modeling of both the anticipated signal and noise. Assuming ice seismicity on Europa behaves according to statistical properties observed in Earth catalogs and scaling cumulative seismic moment release to the moon, we can simulate long seismic records and estimate background noise and peak signal amplitudes (Panning et al., 2017). This suggests a sensitive instrument comparable to many broadband terrestrial instruments or the SP instrument from the InSight mission to Mars will be able to record signals, while high frequency geophones are likely inadequate. We extend this analysis to also begin incorporation of spatial and temporal variation due to the tidal cycle, which can help inform landing site selection. We also begin exploration of how chaotic terrane at the bottom of the ice shell and inter-ice heterogeneities (i.e. internal melt structures) may affect anticipated seismic observations using 2D numerical seismic simulations.M. P. Panning, S. C. Stähler, H.-H. Huang, S. D. Vance, S. Kedar, V. C. Tsai, W. T. Pike, R. D. Lorenz, “Expected seismicity and the seismic noise environment of Europa,” J. Geophys. Res., in revision, 2017.

  5. Seismic structural fragility investigation for the Zion Nuclear Power Plant. Seismic safety margins research program (phase 1)

    International Nuclear Information System (INIS)

    Wesley, D.A.; Hashimoto, P.S.

    1981-10-01

    An evaluation of the seismic capacity of the essential structures for the Zion Nuclear Power Plant in Zion, Illinois, was conducted as part of the Seismic Safety Margins Research Program (SSMRP). The structures included the reactor containment building, the turbine/auxiliary building, and the crib house (intake structure). The evaluation was devoted to seismically induced failures rather than those resulting from combined Loss of Coolant Accident (LOCA) or other extreme load combinations. The seismic loads used in the investigation were based on elastic analyses. The loads for the reactor containment and turbine/auxiliary buildings were developed by Lawrence Livermore Laboratory using time history analyses. The loads used for the crib house were the original seismic design loads developed by Sargent and Lundy. No non-linear seismic analyses were conducted. The seismic capacity of the structures accounted for the actual concrete and steel material properties including the aging of the concrete. Median centered properties were used throughout the evaluation including levels of damping considered appropriate for structures close to collapse as compared to the more conservative values used for design. The inelastic effects were accounted for using ductility modified response spectrum techniques based on system ductility ratios expected for structures near collapse. Sources of both inherent randomness and uncertainties resulting from lack of knowledge or approximations in analytical modelling were considered in developing the dispersion of the structural dynamic characteristics. Coefficients of variation were developed assuming lognormal distributions for all variables. The earthquake levels for many of the seismically induced failure modes are so high as to be considered physically incredible. (author)

  6. Seismic evaluation of existing nuclear facilities. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    Programmes for re-evaluation and upgrading of safety of existing nuclear facilities are presently under way in a number of countries around the world. An important component of these programmes is the re-evaluation of the seismic safety through definition of new seismic parameters at the site and evaluation of seismic capacity of structures, equipment and distribution systems following updated information and criteria. The Seminar is intended to provide a forum for the exchange of information and discussion of the state-of-the-art on seismic safety of nuclear facilities in operation or under construction. Both analytical and experimental techniques for the evaluation of seismic capacity of structures, equipment and distribution systems are discussed. Full scale and field tests of structures and components using shaking tables, mechanical exciters, explosive and shock tests, and ambient vibrations are included in the seminar programme with emphasis on recent case histories. Presentations at the Seminar also include analytical techniques for the determination of dynamic properties of soil-structure systems from experiments as well as calibration of numerical models. Methods and criteria for seismic margin assessment based on experience data obtained from the behaviour of structures and components in real earthquakes are discussed. Guidelines for defining technical requirements for capacity re-evaluation (i.e. acceptable behaviour limits and design and implementation of structure and components upgrades are also presented and discussed. The following topics were covered during 7 sessions: earthquake experience and seismic re-evaluation; country experience in seismic re-evaluation programme; generic WWER studies; analytical methods for seismic capacity re-evaluation; experimental methods for seismic capacity re-evaluation; case studies.

  7. Seismic evaluation of existing nuclear facilities. Proceedings

    International Nuclear Information System (INIS)

    1995-01-01

    Programmes for re-evaluation and upgrading of safety of existing nuclear facilities are presently under way in a number of countries around the world. An important component of these programmes is the re-evaluation of the seismic safety through definition of new seismic parameters at the site and evaluation of seismic capacity of structures, equipment and distribution systems following updated information and criteria. The Seminar is intended to provide a forum for the exchange of information and discussion of the state-of-the-art on seismic safety of nuclear facilities in operation or under construction. Both analytical and experimental techniques for the evaluation of seismic capacity of structures, equipment and distribution systems are discussed. Full scale and field tests of structures and components using shaking tables, mechanical exciters, explosive and shock tests, and ambient vibrations are included in the seminar programme with emphasis on recent case histories. Presentations at the Seminar also include analytical techniques for the determination of dynamic properties of soil-structure systems from experiments as well as calibration of numerical models. Methods and criteria for seismic margin assessment based on experience data obtained from the behaviour of structures and components in real earthquakes are discussed. Guidelines for defining technical requirements for capacity re-evaluation (i.e. acceptable behaviour limits and design and implementation of structure and components upgrades are also presented and discussed. The following topics were covered during 7 sessions: earthquake experience and seismic re-evaluation; country experience in seismic re-evaluation programme; generic WWER studies; analytical methods for seismic capacity re-evaluation; experimental methods for seismic capacity re-evaluation; case studies

  8. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    Energy Technology Data Exchange (ETDEWEB)

    Karyono, E-mail: karyonosu@gmail.com [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia); OSLO University (Norway); Padjadjaran University (UNPAD), Bandung (Indonesia); Mazzini, Adriano; Sugiharto, Anton [OSLO University (Norway); Lupi, Matteo [ETH Zurich (Switzerland); Syafri, Ildrem [Padjadjaran University (UNPAD), Bandung (Indonesia); Masturyono,; Rudiyanto, Ariska; Pranata, Bayu; Muzli,; Widodo, Handi Sulistyo; Sudrajat, Ajat [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia)

    2015-04-24

    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green’s functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  9. Seismic efficiency of meteor airbursts

    Science.gov (United States)

    Svetsov, V. V.; Artemieva, N. A.; Shuvalov, V. V.

    2017-08-01

    We present the results of numerical simulation for impacts of relatively small asteroids and ice bodies of 30-100 m in size, decelerated in the atmosphere and exploding before they reach the surface, but still producing seismic effects due to the impact wave reaching the surface. The calculated magnitudes fall within the range of 4 to 6, and average seismic efficiency of these events is 2.5 × 10-5. The results obtained allow the seismic hazard from impacts of cosmic bodies to be estimated.

  10. Synthesis of artificial spectrum-compatible seismic accelerograms

    International Nuclear Information System (INIS)

    Vrochidou, E; Alvanitopoulos, P F; Andreadis, I; Mallousi, K; Elenas, A

    2014-01-01

    The Hilbert–Huang transform is used to generate artificial seismic signals compatible with the acceleration spectra of natural seismic records. Artificial spectrum-compatible accelerograms are utilized instead of natural earthquake records for the dynamic response analysis of many critical structures such as hospitals, bridges, and power plants. The realistic estimation of the seismic response of structures involves nonlinear dynamic analysis. Moreover, it requires seismic accelerograms representative of the actual ground acceleration time histories expected at the site of interest. Unfortunately, not many actual records of different seismic intensities are available for many regions. In addition, a large number of seismic accelerograms are required to perform a series of nonlinear dynamic analyses for a reliable statistical investigation of the structural behavior under earthquake excitation. These are the main motivations for generating artificial spectrum-compatible seismic accelerograms and could be useful in earthquake engineering for dynamic analysis and design of buildings. According to the proposed method, a single natural earthquake record is deconstructed into amplitude and frequency components using the Hilbert–Huang transform. The proposed method is illustrated by studying 20 natural seismic records with different characteristics such as different frequency content, amplitude, and duration. Experimental results reveal the efficiency of the proposed method in comparison with well-established and industrial methods in the literature. (paper)

  11. Support vector machine in machine condition monitoring and fault diagnosis

    Science.gov (United States)

    Widodo, Achmad; Yang, Bo-Suk

    2007-08-01

    Recently, the issue of machine condition monitoring and fault diagnosis as a part of maintenance system became global due to the potential advantages to be gained from reduced maintenance costs, improved productivity and increased machine availability. This paper presents a survey of machine condition monitoring and fault diagnosis using support vector machine (SVM). It attempts to summarize and review the recent research and developments of SVM in machine condition monitoring and diagnosis. Numerous methods have been developed based on intelligent systems such as artificial neural network, fuzzy expert system, condition-based reasoning, random forest, etc. However, the use of SVM for machine condition monitoring and fault diagnosis is still rare. SVM has excellent performance in generalization so it can produce high accuracy in classification for machine condition monitoring and diagnosis. Until 2006, the use of SVM in machine condition monitoring and fault diagnosis is tending to develop towards expertise orientation and problem-oriented domain. Finally, the ability to continually change and obtain a novel idea for machine condition monitoring and fault diagnosis using SVM will be future works.

  12. The project and technical study on the track of vertical axis linkage abrasive belt grinding of turbine blade

    International Nuclear Information System (INIS)

    Ma Yujian; Tang Xiaoqi; Chen Jihong; Yang Jianzhong

    2010-01-01

    A method of CNC turbine blade profile abrasive belt grinding is introduced based on optimum grinding effect, where the direction of the axis of trolley wheel is consistent with that of minimum principal curvature on the contact point of turbine blade. And the cutter location path is determined, and then the NC code is derived from post-processing. A virtual machine model is built in VERICUT software to simulate actual grinding process and applied in practice, which yielded satisfactory results. (authors)

  13. Statistical Properties of Seismic Noise Measured in Underground Spaces During Seismic Swarm

    Czech Academy of Sciences Publication Activity Database

    Lyubushin, A. A.; Kaláb, Zdeněk; Lednická, Markéta

    2014-01-01

    Roč. 49, č. 2 (2014), s. 209-224 ISSN 2213-5812 R&D Projects: GA ČR GA105/09/0089; GA MŠk LM2010008 Institutional support: RVO:68145535 Keywords : seismic noise * multifractals * wavelets * kurtosis * West Bohemia seismic swarm Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.543, year: 2014 http://link.springer.com/article/10.1007/s40328-014-0051-y

  14. Synthetic seismic acceleration time-histories and their acceptance criteria

    International Nuclear Information System (INIS)

    Xu Hong

    1996-01-01

    In seismic dynamic response analysis of structures and equipment, time-history analysis is now widely used. The 3-D seismic acceleration time-histories or 3-D seismic displacement time-histories are required in the 3-D seismic dynamic response analysis as the seismic excitation input data. Because of the lack of actual acceleration time-histories for the field where the structures or equipment are installed, the general practice is to use the synthetic seismic acceleration time-histories, which are derived from the design seismic response spectra of the field, as the seismic excitation input data. However, from one specified design response spectrum indefinite solutions of acceleration time-histories can be derived depending on the values of the input parameters. Not all the derived synthetic time-histories can be used as seismic excitation input data. Only those which meet the acceptance criteria can be used. The factors (input parameters), which will affect the time-history solution from a specified seismic response spectrum, and the acceptance criteria are discussed

  15. The 2012 Ferrara seismic sequence: Regional crustal structure, earthquake sources, and seismic hazard

    Science.gov (United States)

    Malagnini, Luca; Herrmann, Robert B.; Munafò, Irene; Buttinelli, Mauro; Anselmi, Mario; Akinci, Aybige; Boschi, E.

    2012-10-01

    Inadequate seismic design codes can be dangerous, particularly when they underestimate the true hazard. In this study we use data from a sequence of moderate-sized earthquakes in northeast Italy to validate and test a regional wave propagation model which, in turn, is used to understand some weaknesses of the current design spectra. Our velocity model, while regionalized and somewhat ad hoc, is consistent with geophysical observations and the local geology. In the 0.02-0.1 Hz band, this model is validated by using it to calculate moment tensor solutions of 20 earthquakes (5.6 ≥ MW ≥ 3.2) in the 2012 Ferrara, Italy, seismic sequence. The seismic spectra observed for the relatively small main shock significantly exceeded the design spectra to be used in the area for critical structures. Observations and synthetics reveal that the ground motions are dominated by long-duration surface waves, which, apparently, the design codes do not adequately anticipate. In light of our results, the present seismic hazard assessment in the entire Pianura Padana, including the city of Milan, needs to be re-evaluated.

  16. Seismic behaviour of geotechnical structures

    Directory of Open Access Journals (Sweden)

    F. Vinale

    2002-06-01

    Full Text Available This paper deals with some fundamental considerations regarding the behaviour of geotechnical structures under seismic loading. First a complete definition of the earthquake disaster risk is provided, followed by the importance of performing site-specific hazard analysis. Then some suggestions are provided in regard to adequate assessment of soil parameters, a crucial point to properly analyze the seismic behaviour of geotechnical structures. The core of the paper is centered on a critical review of the analysis methods available for studying geotechnical structures under seismic loadings. All of the available methods can be classified into three main classes, including the pseudo-static, pseudo-dynamic and dynamic approaches, each of which is reviewed for applicability. A more advanced analysis procedure, suitable for a so-called performance-based design approach, is also described in the paper. Finally, the seismic behaviour of the El Infiernillo Dam was investigated. It was shown that coupled elastoplastic dynamic analyses disclose some of the important features of dam behaviour under seismic loading, confirmed by comparing analytical computation and experimental measurements on the dam body during and after a past earthquake.

  17. Adaptive Sensor Tuning for Seismic Event Detection in Environment with Electromagnetic Noise

    Science.gov (United States)

    Ziegler, Abra E.

    The goal of this research is to detect possible microseismic events at a carbon sequestration site. Data recorded on a continuous downhole microseismic array in the Farnsworth Field, an oil field in Northern Texas that hosts an ongoing carbon capture, utilization, and storage project, were evaluated using machine learning and reinforcement learning techniques to determine their effectiveness at seismic event detection on a dataset with electromagnetic noise. The data were recorded from a passive vertical monitoring array consisting of 16 levels of 3-component 15 Hz geophones installed in the field and continuously recording since January 2014. Electromagnetic and other noise recorded on the array has significantly impacted the utility of the data and it was necessary to characterize and filter the noise in order to attempt event detection. Traditional detection methods using short-term average/long-term average (STA/LTA) algorithms were evaluated and determined to be ineffective because of changing noise levels. To improve the performance of event detection and automatically and dynamically detect seismic events using effective data processing parameters, an adaptive sensor tuning (AST) algorithm developed by Sandia National Laboratories was utilized. AST exploits neuro-dynamic programming (reinforcement learning) trained with historic event data to automatically self-tune and determine optimal detection parameter settings. The key metric that guides the AST algorithm is consistency of each sensor with its nearest neighbors: parameters are automatically adjusted on a per station basis to be more or less sensitive to produce consistent agreement of detections in its neighborhood. The effects that changes in neighborhood configuration have on signal detection were explored, as it was determined that neighborhood-based detections significantly reduce the number of both missed and false detections in ground-truthed data. The performance of the AST algorithm was

  18. Probabilistic seismic hazard assessment. Gentilly 2

    International Nuclear Information System (INIS)

    1996-03-01

    Results of this probabilistic seismic hazard assessment were determined using a suite of conservative assumptions. The intent of this study was to perform a limited hazard assessment that incorporated a range of technically defensible input parameters. To best achieve this goal, input selected for the hazard assessment tended to be conservative with respect to selection of attenuation modes, and seismicity parameters. Seismic hazard estimates at Gentilly 2 were most affected by selection of the attenuation model. Alternative definitions of seismic source zones had a relatively small impact on seismic hazard. A St. Lawrence Rift model including a maximum magnitude of 7.2 m b in the zone containing the site had little effect on the hazard estimate relative to other seismic source zonation models. Mean annual probabilities of exceeding the design peak ground acceleration, and the design response spectrum for the Gentilly 2 site were computed to lie in the range of 0.001 to 0.0001. This hazard result falls well within the range determined to be acceptable for nuclear reactor sites located throughout the eastern United States. (author) 34 refs., 6 tabs., 28 figs

  19. Seismic Safety Of Simple Masonry Buildings

    International Nuclear Information System (INIS)

    Guadagnuolo, Mariateresa; Faella, Giuseppe

    2008-01-01

    Several masonry buildings comply with the rules for simple buildings provided by seismic codes. For these buildings explicit safety verifications are not compulsory if specific code rules are fulfilled. In fact it is assumed that their fulfilment ensures a suitable seismic behaviour of buildings and thus adequate safety under earthquakes. Italian and European seismic codes differ in the requirements for simple masonry buildings, mostly concerning the building typology, the building geometry and the acceleration at site. Obviously, a wide percentage of buildings assumed simple by codes should satisfy the numerical safety verification, so that no confusion and uncertainty have to be given rise to designers who must use the codes. This paper aims at evaluating the seismic response of some simple unreinforced masonry buildings that comply with the provisions of the new Italian seismic code. Two-story buildings, having different geometry, are analysed and results from nonlinear static analyses performed by varying the acceleration at site are presented and discussed. Indications on the congruence between code rules and results of numerical analyses performed according to the code itself are supplied and, in this context, the obtained result can provide a contribution for improving the seismic code requirements

  20. Detailed geological characterisation from seismic data

    Energy Technology Data Exchange (ETDEWEB)

    Peter Hatherly; Binzhong Zhou; Troy Peters; Milovan Urosevic [CRC Mining (Australia)

    2009-02-15

    The use of seismic reflection surveying continues to grow within Australia's underground coal mining regions of the Sydney and Bowen Basins. For this project, the potential for acoustic impedance inversion to complement the information available from conventional seismic surveys was investigated. Acoustic impedance is defined by the product of seismic P-wave velocity and rock density. The methods of seismic inversion have been developed mainly for the investigation of petroleum reservoirs. Commercial software packages are available and for this project we utilised the Hampson and Russell software available at Curtin University of Technology. For the true amplitude processing of the seismic data, the Promax software operated at Velseis Processing was used. Inversions were undertaken for three 3D seismic surveys and two 2D surveys. The sites were at Grasstree and North Goonyella Mines in the Bowen Basin and at West Cliff and Dendrobium Collieries in the Sydney Basin. An empirical relationship was derived between acoustic impedance and the newly developed Geophysical Strata Rating (GSR). This allows impedance values to be converted into GSR values that have more meaning in geotechnical assessment. To obtain satisfactory inversions, we used the model based approach.

  1. Seismic hazard map of the western hemisphere

    Science.gov (United States)

    Shedlock, K.M.; Tanner, J.G.

    1999-01-01

    Vulnerability to natural disasters increases with urbanization and development of associated support systems (reservoirs, power plants, etc.). Catastrophic earthquakes account for 60% of worldwide casualties associated with natural disasters. Economic damage from earthquakes is increasing, even in technologically advanced countries with some level of seismic zonation, as shown by the 1989 Loma Prieta, CA ($6 billion), 1994 Northridge, CA ($ 25 billion), and 1995 Kobe, Japan (> $ 100 billion) earthquakes. The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures, due to an insufficient knowledge of existing seismic hazard. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes), emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of the Americas is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful global seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA) with a 10% chance of exceedance in 50 years for the western hemisphere. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the

  2. Seismic hazard map of the western hemisphere

    Directory of Open Access Journals (Sweden)

    J. G. Tanner

    1999-06-01

    Full Text Available Vulnerability to natural disasters increases with urbanization and development of associated support systems (reservoirs, power plants, etc.. Catastrophic earthquakes account for 60% of worldwide casualties associated with natural disasters. Economic damage from earthquakes is increasing, even in technologically advanced countries with some level of seismic zonation, as shown by the 1989 Loma Prieta, CA ($ 6 billion, 1994 Northridge, CA ($ 25 billion, and 1995 Kobe, Japan (> $ 100 billion earthquakes. The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures, due to an insufficient knowledge of existing seismic hazard. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes, emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of the Americas is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful global seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA with a 10% chance of exceedance in 50 years for the western hemisphere. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions

  3. Calculation of NPP pipeline seismic stability

    International Nuclear Information System (INIS)

    Kirillov, A.P.; Ambriashvili, Yu.K.; Kaliberda, I.V.

    1982-01-01

    A simplified design procedure of seismic pipeline stability of NPP at WWER reactor is described. The simplified design procedure envisages during the selection and arrangement of pipeline saddle and hydraulic shock absorbers use of method of introduction of resilient mountings of very high rigidity into the calculated scheme of the pipeline and performance of calculations with step-by-step method. It is concluded that the application of the design procedure considered permits to determine strains due to seismic loads, to analyze stressed state in pipeline elements and supporting power of pipe-line saddle with provision for seismic loads to plan measures on seismic protection

  4. Seismic Performance Evaluation of Reinforced Concrete Frames Subjected to Seismic Loads

    Science.gov (United States)

    Zameeruddin, Mohd.; Sangle, Keshav K.

    2017-06-01

    Ten storied-3 bays reinforced concrete bare frame designed for gravity loads following the guidelines of IS 456 and IS 13920 for ductility is subjected to seismic loads. The seismic demands on this building were calculated by following IS 1893 for response spectra of 5% damping (for hard soil type). Plastic hinges were assigned to the beam and column at both ends to represent the failure mode, when member yields. Non-linear static (pushover) analysis was performed to evaluate the performance of the building in reference to first (ATC 40), second (FEMA 356) and next-generation (FEMA 440) performance based seismic design procedures. Base shear against top displacement curve of structure, known as pushover curve was obtained for two actions of plastic hinge behavior, force-controlled (brittle) and deformation-controlled (ductile) actions. Lateral deformation corresponding to performance point proves the building capability to sustain a certain level of seismic loads. The failure is represented by a sequence of formation of plastic hinges. Deformation-controlled action of hinges showed that building behaves like strong-column-weak-beam mechanism, whereas force-controlled action showed formation of hinges in the column. The study aims to understand the first, second and next generation performance based design procedure in prediction of actual building responses and their conservatism into the acceptance criteria.

  5. Constraints on mantle convection from seismic tomography

    NARCIS (Netherlands)

    Kárason, H.; Hilst, R.D. van der

    2000-01-01

    Since the advent of global seismic tomography some 25 years ago, advances in technology, seismological theory, and data acquisition have allowed spectacular progress in our ability to image seismic heterogeneity in Earth's mantle. We briefly review some concepts of seismic tomography, such as

  6. Review of nuclear piping seismic design requirements

    International Nuclear Information System (INIS)

    Slagis, G.C.; Moore, S.E.

    1994-01-01

    Modern-day nuclear plant piping systems are designed with a large number of seismic supports and snubbers that may be detrimental to plant reliability. Experimental tests have demonstrated the inherent ruggedness of ductile steel piping for seismic loading. Present methods to predict seismic loads on piping are based on linear-elastic analysis methods with low damping. These methods overpredict the seismic response of ductile steel pipe. Section III of the ASME Boiler and Pressure Vessel Code stresses limits for piping systems that are based on considerations of static loads and hence are overly conservative. Appropriate stress limits for seismic loads on piping should be incorporated into the code to allow more flexible piping designs. The existing requirements and methods for seismic design of piping systems, including inherent conservations, are explained to provide a technical foundation for modifications to those requirements. 30 refs., 5 figs., 3 tabs

  7. Some preliminary results of a worldwide seismicity estimation: a case study of seismic hazard evaluation in South America

    Directory of Open Access Journals (Sweden)

    C. V. Christova

    2000-06-01

    Full Text Available Global data have been widely used for seismicity and seismic hazard assessment by seismologists. In the present study we evaluate worldwide seismicity in terms of maps of maximum observed magnitude (Mmax, seismic moment (M 0 and seismic moment rate (M 0S. The data set used consists of a complete and homogeneous global catalogue of shallow (h £ 60 km earthquakes of magnitude MS ³ 5.5 for the time period 1894-1992. In order to construct maps of seismicity and seismic hazard the parameters a and b derived from the magnitude-frequency relationship were estimated by both: a the least squares, and b the maximum likelihood, methods. The values of a and b were determined considering circles centered at each grid point 1° (of a mesh 1° ´1° and of varying radius, which starts from 30 km and moves with a step of 10 km. Only a and b values which fulfill some predefined conditions were considered in the further procedure for evaluating the seismic hazard maps. The obtained worldwide M max distribution in general delineates the contours of the plate boundaries. The highest values of M max observed are along the circum-Pacific belt and in the Himalayan area. The subduction plate boundaries are characterized by the largest amount of M 0 , while areas of continental collision are next. The highest values of seismic moment rate (per 1 year and per equal area of 10 000 km 2 are found in the Southern Himalayas. The western coasts of U.S.A., Northwestern Canada and Alaska, the Indian Ocean and the eastern rift of Africa are characterized by high values of M 0 , while most of the Pacific subduction zones have lower values of seismic moment rate. Finally we analyzed the seismic hazard in South America comparing the predicted by the NUVEL1 model convergence slip rate between Nazca and South America plates with the average slip rate due to earthquakes. This consideration allows for distinguishing between zones of high and low coupling along the studied convergence

  8. Simulations of Quantum Turing Machines by Quantum Multi-Stack Machines

    OpenAIRE

    Qiu, Daowen

    2005-01-01

    As was well known, in classical computation, Turing machines, circuits, multi-stack machines, and multi-counter machines are equivalent, that is, they can simulate each other in polynomial time. In quantum computation, Yao [11] first proved that for any quantum Turing machines $M$, there exists quantum Boolean circuit $(n,t)$-simulating $M$, where $n$ denotes the length of input strings, and $t$ is the number of move steps before machine stopping. However, the simulations of quantum Turing ma...

  9. Seismic-Scale Rock Physics of Methane Hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Amos Nur

    2009-01-08

    We quantify natural methane hydrate reservoirs by generating synthetic seismic traces and comparing them to real seismic data: if the synthetic matches the observed data, then the reservoir properties and conditions used in synthetic modeling might be the same as the actual, in-situ reservoir conditions. This approach is model-based: it uses rock physics equations that link the porosity and mineralogy of the host sediment, pressure, and hydrate saturation, and the resulting elastic-wave velocity and density. One result of such seismic forward modeling is a catalogue of seismic reflections of methane hydrate which can serve as a field guide to hydrate identification from real seismic data. We verify this approach using field data from known hydrate deposits.

  10. Next-generation probabilistic seismicity forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Hiemer, S.

    2014-07-01

    The development of probabilistic seismicity forecasts is one of the most important tasks of seismologists at present time. Such forecasts form the basis of probabilistic seismic hazard assessment, a widely used approach to generate ground motion exceedance maps. These hazard maps guide the development of building codes, and in the absence of the ability to deterministically predict earthquakes, good building and infrastructure planning is key to prevent catastrophes. Probabilistic seismicity forecasts are models that specify the occurrence rate of earthquakes as a function of space, time and magnitude. The models presented in this thesis are time-invariant mainshock occurrence models. Accordingly, the reliable estimation of the spatial and size distribution of seismicity are of crucial importance when constructing such probabilistic forecasts. Thereby we focus on data-driven approaches to infer these distributions, circumventing the need for arbitrarily chosen external parameters and subjective expert decisions. Kernel estimation has been shown to appropriately transform discrete earthquake locations into spatially continuous probability distributions. However, we show that neglecting the information from fault networks constitutes a considerable shortcoming and thus limits the skill of these current seismicity models. We present a novel earthquake rate forecast that applies the kernel-smoothing method to both past earthquake locations and slip rates on mapped crustal faults applied to Californian and European data. Our model is independent from biases caused by commonly used non-objective seismic zonations, which impose artificial borders of activity that are not expected in nature. Studying the spatial variability of the seismicity size distribution is of great importance. The b-value of the well-established empirical Gutenberg-Richter model forecasts the rates of hazard-relevant large earthquakes based on the observed rates of abundant small events. We propose a

  11. Next-generation probabilistic seismicity forecasting

    International Nuclear Information System (INIS)

    Hiemer, S.

    2014-01-01

    The development of probabilistic seismicity forecasts is one of the most important tasks of seismologists at present time. Such forecasts form the basis of probabilistic seismic hazard assessment, a widely used approach to generate ground motion exceedance maps. These hazard maps guide the development of building codes, and in the absence of the ability to deterministically predict earthquakes, good building and infrastructure planning is key to prevent catastrophes. Probabilistic seismicity forecasts are models that specify the occurrence rate of earthquakes as a function of space, time and magnitude. The models presented in this thesis are time-invariant mainshock occurrence models. Accordingly, the reliable estimation of the spatial and size distribution of seismicity are of crucial importance when constructing such probabilistic forecasts. Thereby we focus on data-driven approaches to infer these distributions, circumventing the need for arbitrarily chosen external parameters and subjective expert decisions. Kernel estimation has been shown to appropriately transform discrete earthquake locations into spatially continuous probability distributions. However, we show that neglecting the information from fault networks constitutes a considerable shortcoming and thus limits the skill of these current seismicity models. We present a novel earthquake rate forecast that applies the kernel-smoothing method to both past earthquake locations and slip rates on mapped crustal faults applied to Californian and European data. Our model is independent from biases caused by commonly used non-objective seismic zonations, which impose artificial borders of activity that are not expected in nature. Studying the spatial variability of the seismicity size distribution is of great importance. The b-value of the well-established empirical Gutenberg-Richter model forecasts the rates of hazard-relevant large earthquakes based on the observed rates of abundant small events. We propose a

  12. Seismic activity in northeastern Brazill-new perspectives

    Science.gov (United States)

    Ferreira, J. M.; Do Nascimento, A. F.; Vilar, C. S.; Bezerra, F. H.; Assumpcao, M.; Berrocal, J.; Fuck, R. A.

    2007-05-01

    Northeastern Brazil is the most seismic active region in the country. Some earthquakes with magnitude above 5.0 and intensity VII MM associated with swam-like seismic activity lasting for many years are a serious social concern. Since the 1980's macroseismic and instrumental surveys have been carried out in this region and they are an important data archive which allows the composition of a reliable catalogue of seismic activity for this region. Among the many scientific results it was possible to identify the main seismogenic areas, obtain reliable hypocentres and focal mechanisms. As a consequence, it was possible also to analyse the relationship between seismicity and geological features. It was also possible to determined maximum horizontal stress direction for the region. An important induced seismic activity case has also been reported in the area as being a classical example of pore pressure diffusion triggering mechanism. The majority of the results were obtained using analogic data. Recently, a new research project is being conducted and will allow us to provide a regional scale monitoring with 6 broad-band stations and a new portable six station digital seismic network equipped with short- period sensors. Thus, with the continuous seismic activity in the area we trust that the results of this project will increase the present knowledge of seismic activity in northeastern Brazil.

  13. Seismic attributes and advanced computer algorithm to predict formation pore pressure: Qalibah formation of Northwest Saudi Arabia

    Science.gov (United States)

    Nour, Abdoulshakour M.

    Oil and gas exploration professionals have long recognized the importance of predicting pore pressure before drilling wells. Pre-drill pore pressure estimation not only helps with drilling wells safely but also aids in the determination of formation fluids migration and seal integrity. With respect to the hydrocarbon reservoirs, the appropriate drilling mud weight is directly related to the estimated pore pressure in the formation. If the mud weight is lower than the formation pressure, a blowout may occur, and conversely, if it is higher than the formation pressure, the formation may suffer irreparable damage due to the invasion of drilling fluids into the formation. A simple definition of pore pressure is the pressure of the pore fluids in excess of the hydrostatic pressure. In this thesis, I investigated the utility of advance computer algorithm called Support Vector Machine (SVM) to learn the pattern of high pore pressure regime, using seismic attributes such as Instantaneous phase, t*Attenuation, Cosine of Phase, Vp/Vs ratio, P-Impedance, Reflection Acoustic Impedance, Dominant frequency and one well attribute (Mud-Weigh) as the learning dataset. I applied this technique to the over pressured Qalibah formation of Northwest Saudi Arabia. The results of my research revealed that in the Qalibah formation of Northwest Saudi Arabia, the pore pressure trend can be predicted using SVM with seismic and well attributes as the learning dataset. I was able to show the pore pressure trend at any given point within the geographical extent of the 3D seismic data from which the seismic attributes were derived. In addition, my results surprisingly showed the subtle variation of pressure within the thick succession of shale units of the Qalibah formation.

  14. Dynamic characteristics of background seismic noise according to records of nuclear monitoring seismic stations in Kazakstan

    International Nuclear Information System (INIS)

    Belyashova, N.N.; Sinyova, Z.I.; Komarov, I.I.; Mikhailova, N.N.

    1998-01-01

    The seismic stations of Kazakstan, included into nuclear monitoring network (see fig.1) are equipped with broad hand seismometers; seismic data are recorded in digital format. All this allows to investigate spectral and time characteristics of seismic background noise in very large frequency diapason (more than 3-5 orders), for all three components of oscillation vector. The spectral density of background seismic noise for vertical and both horizontal components (fig.2) was calculated for all of the observation points. The regular features of structure of noise spectra, inherent for all of the studied observation points, as well as some features, specific for studied places were found. The curves of spectral noise density were compared with global noise model, determined by the data of Global Seismological Network (GSN)

  15. Seismic investigations for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Barrows, L.J.

    1984-01-01

    Evaporite rocks in the Delaware Basin in southeastern New Mexico are being investigated as a possible site for nuclear waste disposal. Seismic studies have been conducted to establish seismic design criteria and to investigate relations between seismicity and geologic structures. In the initial phase of this study, historical and available seismic data were interpreted with respect to geology. Local instrumentation became available in 1974 when New Mexico Tech installed and began operating a seismic station in the area. Data and interpretation for 1974 through 1979 have been published. In 1980 seismic monitoring of the Northern Delaware Basin was extended to include a six station network of self-contained radio-telemetered seismometers. 9 references, 13 figures

  16. Development of an evaluation method for seismic isolation systems of nuclear power facilities. Seismic design analysis methods for crossover piping system

    International Nuclear Information System (INIS)

    Tai, Koichi; Sasajima, Keisuke; Fukushima, Shunsuke; Takamura, Noriyuki; Onishi, Shigenobu

    2014-01-01

    This paper provides seismic design analysis methods suitable for crossover piping system, which connects between seismic isolated building and non-isolated building in the seismic isolated nuclear power plant. Through the numerical study focused on the main steam crossover piping system, seismic response spectrum analysis applying ISM (Independent Support Motion) method with SRSS combination or CCFS (Cross-oscillator, Cross-Floor response Spectrum) method has found to be quite effective for the seismic design of multiply supported crossover piping system. (author)

  17. Nuclear power plants seismic review programme in Spain

    International Nuclear Information System (INIS)

    Sanchez Cabanero, J.G.; Jimenez Juan, A.

    1995-01-01

    This presentation deals with seismic design and seismic reevaluation of Spanish operating nuclear power plants. The Spanish NPPs owners Probabilistic seismic hazard study requires an independent and deep review of methodology, modelling techniques, data management and method of eliciting in order to make decision on its acceptability. It reflects the opinion of only one expert tem and it would be necessary to involve more expert opinions to consider the uncertainties. It is proposed to evaluate the probabilistic seismic hazard study and the seismic categorisation

  18. Test on large-scale seismic isolation elements, 2

    International Nuclear Information System (INIS)

    Mazda, T.; Moteki, M.; Ishida, K.; Shiojiri, H.; Fujita, T.

    1991-01-01

    Seismic isolation test program of Central Research Inst. of Electric Power Industry (CRIEPI) to apply seismic isolation to Fast Breeder Reactor (FBR) plant was started in 1987. In this test program, demonstration test of seismic isolation elements was considered as one of the most important research items. Facilities for testing seismic isolation elements were built in Abiko Research Laboratory of CRIEPI. Various tests of large-scale seismic isolation elements were conducted up to this day. Many important test data to develop design technical guidelines was obtained. (author)

  19. seismic refraction investigation of the subsurface structure

    African Journals Online (AJOL)

    DR. AMINU

    employed for exploration include magnetic, electrical and gravitational methods, which depends on the earth's natural fields. Others are seismic and electromagnetic methods, which depends on the introduction of artificial energy in thereof. The seismic refraction method uses the seismic energy that returns to the surface of ...

  20. The Great Maule earthquake: seismicity prior to and after the main shock from amphibious seismic networks

    Science.gov (United States)

    Lieser, K.; Arroyo, I. G.; Grevemeyer, I.; Flueh, E. R.; Lange, D.; Tilmann, F. J.

    2013-12-01

    The Chilean subduction zone is among the seismically most active plate boundaries in the world and its coastal ranges suffer from a magnitude 8 or larger megathrust earthquake every 10-20 years. The Constitución-Concepción or Maule segment in central Chile between ~35.5°S and 37°S was considered to be a mature seismic gap, rupturing last in 1835 and being seismically quiet without any magnitude 4.5 or larger earthquakes reported in global catalogues. It is located to the north of the nucleation area of the 1960 magnitude 9.5 Valdivia earthquake and to the south of the 1928 magnitude 8 Talca earthquake. On 27 February 2010 this segment ruptured in a Mw=8.8 earthquake, nucleating near 36°S and affecting a 500-600 km long segment of the margin between 34°S and 38.5°S. Aftershocks occurred along a roughly 600 km long portion of the central Chilean margin, most of them offshore. Therefore, a network of 30 ocean-bottom-seismometers was deployed in the northern portion of the rupture area for a three month period, recording local offshore aftershocks between 20 September 2010 and 25 December 2010. In addition, data of a network consisting of 33 landstations of the GeoForschungsZentrum Potsdam were included into the network, providing an ideal coverage of both the rupture plane and areas affected by post-seismic slip as deduced from geodetic data. Aftershock locations are based on automatically detected P wave onsets and a 2.5D velocity model of the combined on- and offshore network. Aftershock seismicity analysis in the northern part of the survey area reveals a well resolved seismically active splay fault in the accretionary prism of the Chilean forearc. Our findings imply that in the northernmost part of the rupture zone, co-seismic slip most likely propagated along the splay fault and not the subduction thrust fault. In addition, the updip limit of aftershocks along the plate interface can be verified to about 40 km landwards from the deformation front. Prior to

  1. Hanford annual second quarter seismic report, fiscal year 1998: Seismicity on and near the Hanford Site, Pasco, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Hartshorn, D.C.; Reidel, S.P.; Rohay, A.C.

    1998-06-01

    Hanford Seismic Monitoring provides an uninterrupted collection of high quality raw and processed seismic data from the Hanford Seismic Network (HSN) for the US Department of Energy and its contractors. The staff also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compiled, archived, and published for use by the Hanford Site for waste management, Natural Phenomena Hazards assessments, and engineering design and construction. In addition, the seismic monitoring organization works with the Hanford Site Emergency Services Organization to provide assistance in the event of an earthquake on the Hanford Site. The HSN and the Eastern Washington Regional Network (ENN) consist of 42 individual sensor sites and 15 radio relay sites maintained by the Hanford Seismic Monitoring staff. The operational rate for the second quarter of FY98 for stations in the HSN was 99.92%. The operational rate for the second quarter of FY98 for stations of the EWRN was 99.46%. For the second quarter of FY98, the acquisition computer triggered 159 times. Of these triggers 14 were local earthquakes: 7 (50%) in the Columbia River Basalt Group, 3 (21%) in the pre-basalt sediments, and 4 (29%) in the crystalline basement. The geologic and tectonic environments where these earthquakes occurred are discussed in this report. The most significant seismic event for the second quarter was on March 23, 1998 when a 1.9 Mc occurred near Eltopia, WA and was felt by local residents. Although this was a small event, it was felt at the surface and is an indication of the potential impact on Hanford of seismic events that are common to the Site.

  2. IAEA establishes International Seismic Safety Centre

    International Nuclear Information System (INIS)

    2008-01-01

    Full text: The IAEA today officially inaugurated an international centre to coordinate efforts for protecting nuclear installations against the effects of earthquakes. The International Seismic Safety Centre (ISSC), which has been established within the IAEA's Department of Nuclear Safety and Security, will serve as a focal point on seismic safety for nuclear installations worldwide. ISSC will assist countries on the assessment of seismic hazards of nuclear facilities to mitigate the consequences of strong earthquakes. 'With safety as our first priority, it is vital that we pool all expert knowledge available worldwide to assist nuclear operators and regulators to be well prepared for coping with major seismic events,' said Antonio Godoy, Acting Head of the IAEA's Engineering Safety Section and leader of the ISSC. 'The creation of the ISSC represents the culmination of three decades of the IAEA's active and recognized involvement in this matter through the development of an updated set of safety standards and the assistance to Member States for their application.' To further seismic safety at nuclear installations worldwide, the ISSC will: - Promote knowledge sharing among the international community in order to avoid or mitigate the consequences of extreme seismic events on nuclear installations; - Support countries through advisory services and training courses; and - Enhance seismic safety by utilizing experience gained from previous seismic events in member states. The centre is supported by a scientific committee of high-level experts from academic, industrial and nuclear safety authorities that will advise the ISSC on implementation of its programme. Experts have been nominated from seven specialized areas, including geology and tectonics, seismology, seismic hazard, geotechnical engineering, structural engineering, equipment, and seismic risk. Japan and the United States have both contributed initial funds for creation of the centre, which will be based at

  3. Machine tool structures

    CERN Document Server

    Koenigsberger, F

    1970-01-01

    Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration c

  4. Experiments on seismic metamaterials: molding surface waves.

    Science.gov (United States)

    Brûlé, S; Javelaud, E H; Enoch, S; Guenneau, S

    2014-04-04

    Materials engineered at the micro- and nanometer scales have had a tremendous and lasting impact in photonics and phononics. At much larger scales, natural soils civil engineered at decimeter to meter scales may interact with seismic waves when the global properties of the medium are modified, or alternatively thanks to a seismic metamaterial constituted of a mesh of vertical empty inclusions bored in the initial soil. Here, we show the experimental results of a seismic test carried out using seismic waves generated by a monochromatic vibrocompaction probe. Measurements of the particles' velocities show a modification of the seismic energy distribution in the presence of the metamaterial in agreement with numerical simulations using an approximate plate model. For complex natural materials such as soils, this large-scale experiment was needed to show the practical feasibility of seismic metamaterials and to stress their importance for applications in civil engineering. We anticipate this experiment to be a starting point for smart devices for anthropic and natural vibrations.

  5. Seismic safety in conducting large-scale blasts

    Science.gov (United States)

    Mashukov, I. V.; Chaplygin, V. V.; Domanov, V. P.; Semin, A. A.; Klimkin, M. A.

    2017-09-01

    In mining enterprises to prepare hard rocks for excavation a drilling and blasting method is used. With the approach of mining operations to settlements the negative effect of large-scale blasts increases. To assess the level of seismic impact of large-scale blasts the scientific staff of Siberian State Industrial University carried out expertise for coal mines and iron ore enterprises. Determination of the magnitude of surface seismic vibrations caused by mass explosions was performed using seismic receivers, an analog-digital converter with recording on a laptop. The registration results of surface seismic vibrations during production of more than 280 large-scale blasts at 17 mining enterprises in 22 settlements are presented. The maximum velocity values of the Earth’s surface vibrations are determined. The safety evaluation of seismic effect was carried out according to the permissible value of vibration velocity. For cases with exceedance of permissible values recommendations were developed to reduce the level of seismic impact.

  6. Mobile seismic exploration

    Energy Technology Data Exchange (ETDEWEB)

    Dräbenstedt, A., E-mail: a.draebenstedt@polytec.de, E-mail: rembe@iei.tu-clausthal.de, E-mail: ulrich.polom@liag-hannover.de; Seyfried, V. [Research & Development, Polytec GmbH, Waldbronn (Germany); Cao, X.; Rembe, C., E-mail: a.draebenstedt@polytec.de, E-mail: rembe@iei.tu-clausthal.de, E-mail: ulrich.polom@liag-hannover.de [Institute of Electrical Information Technology, TU Clausthal, Clausthal-Zellerfeld (Germany); Polom, U., E-mail: a.draebenstedt@polytec.de, E-mail: rembe@iei.tu-clausthal.de, E-mail: ulrich.polom@liag-hannover.de [Leibniz Institute of Applied Geophysics, Hannover (Germany); Pätzold, F.; Hecker, P. [Institute of Flight Guidance, TU Braunschweig, Braunschweig (Germany); Zeller, T. [Clausthaler Umwelttechnik Institut CUTEC, Clausthal-Zellerfeld (Germany)

    2016-06-28

    Laser-Doppler-Vibrometry (LDV) is an established technique to measure vibrations in technical systems with picometer vibration-amplitude resolution. Especially good sensitivity and resolution can be achieved at an infrared wavelength of 1550 nm. High-resolution vibration measurements are possible over more than 100 m distance. This advancement of the LDV technique enables new applications. The detection of seismic waves is an application which has not been investigated so far because seismic waves outside laboratory scales are usually analyzed at low frequencies between approximately 1 Hz and 250 Hz and require velocity resolutions in the range below 1 nm/s/√Hz. Thermal displacements and air turbulence have critical influences to LDV measurements at this low-frequency range leading to noise levels of several 100 nm/√Hz. Commonly seismic waves are measured with highly sensitive inertial sensors (geophones or Micro Electro-Mechanical Sensors (MEMS)). Approaching a laser geophone based on LDV technique is the topic of this paper. We have assembled an actively vibration-isolated optical table in a minivan which provides a hole in its underbody. The laser-beam of an infrared LDV assembled on the optical table impinges the ground below the car through the hole. A reference geophone has detected remaining vibrations on the table. We present the results from the first successful experimental demonstration of contactless detection of seismic waves from a movable vehicle with a LDV as laser geophone.

  7. Consideration of vertical seismic response spectrum in nuclear safety review

    International Nuclear Information System (INIS)

    Sun Zaozhan; Huang Bingchen

    2011-01-01

    The basic requirements for civil nuclear installation are introduced in the article. Starting from the basic concept of seismic response spectrum, the authors analyze the site seismic response spectrum and the design seismic response spectrum that desire much consideration. By distinguishing the absolute seismic response spectrum and relative seismic response spectrum, the authors analyze the difference and relationship between the vertical seismic response spectrum and horizontal seismic response spectrum. The authors also bring forward some suggestions for determining the site vertical seismic response spectrum by considering the fact in our country. (authors)

  8. Seismic Imaging of the Source Physics Experiment Site with the Large-N Seismic Array

    Science.gov (United States)

    Chen, T.; Snelson, C. M.; Mellors, R. J.

    2017-12-01

    The Source Physics Experiment (SPE) consists of a series of chemical explosions at the Nevada National Security Site. The goal of SPE is to understand seismic wave generation and propagation from these explosions. To achieve this goal, we need an accurate geophysical model of the SPE site. A Large-N seismic array that was deployed at the SPE site during one of the chemical explosions (SPE-5) helps us construct high-resolution local geophysical model. The Large-N seismic array consists of 996 geophones, and covers an area of approximately 2 × 2.5 km. The array is located in the northern end of the Yucca Flat basin, at a transition from Climax Stock (granite) to Yucca Flat (alluvium). In addition to the SPE-5 explosion, the Large-N array also recorded 53 weight drops. Using the Large-N seismic array recordings, we perform body wave and surface wave velocity analysis, and obtain 3D seismic imaging of the SPE site for the top crust of approximately 1 km. The imaging results show clear variation of geophysical parameter with local geological structures, including heterogeneous weathering layer and various rock types. The results of this work are being incorporated in the larger 3D modeling effort of the SPE program to validate the predictive models developed for the site.

  9. Time-dependent seismic tomography

    Science.gov (United States)

    Julian, B.R.; Foulger, G.R.

    2010-01-01

    Of methods for measuring temporal changes in seismic-wave speeds in the Earth, seismic tomography is among those that offer the highest spatial resolution. 3-D tomographic methods are commonly applied in this context by inverting seismic wave arrival time data sets from different epochs independently and assuming that differences in the derived structures represent real temporal variations. This assumption is dangerous because the results of independent inversions would differ even if the structure in the Earth did not change, due to observational errors and differences in the seismic ray distributions. The latter effect may be especially severe when data sets include earthquake swarms or aftershock sequences, and may produce the appearance of correlation between structural changes and seismicity when the wave speeds are actually temporally invariant. A better approach, which makes it possible to assess what changes are truly required by the data, is to invert multiple data sets simultaneously, minimizing the difference between models for different epochs as well as the rms arrival-time residuals. This problem leads, in the case of two epochs, to a system of normal equations whose order is twice as great as for a single epoch. The direct solution of this system would require twice as much memory and four times as much computational effort as would independent inversions. We present an algorithm, tomo4d, that takes advantage of the structure and sparseness of the system to obtain the solution with essentially no more effort than independent inversions require. No claim to original US government works Journal compilation ?? 2010 RAS.

  10. Redatuming of sparse 3D seismic data

    NARCIS (Netherlands)

    Tegtmeier, S.

    2007-01-01

    The purpose of a seismic survey is to produce an image of the subsurface providing an overview of the earth's discontinuities. The aim of seismic processing is to recreate this image. The seismic method is especially well suited for the exploration and the monitoring of hydrocarbon reservoirs. A

  11. Electricity of machine tool

    International Nuclear Information System (INIS)

    Gijeon media editorial department

    1977-10-01

    This book is divided into three parts. The first part deals with electricity machine, which can taints from generator to motor, motor a power source of machine tool, electricity machine for machine tool such as switch in main circuit, automatic machine, a knife switch and pushing button, snap switch, protection device, timer, solenoid, and rectifier. The second part handles wiring diagram. This concludes basic electricity circuit of machine tool, electricity wiring diagram in your machine like milling machine, planer and grinding machine. The third part introduces fault diagnosis of machine, which gives the practical solution according to fault diagnosis and the diagnostic method with voltage and resistance measurement by tester.

  12. Seismic safety of Paks nuclear power plant

    International Nuclear Information System (INIS)

    Katona, T.

    1993-01-01

    An extensive program is underway at Paks NPP for evaluation of the seismic safety and for development of the necessary safety increasing measures. This program includes the following five measures: investigation of methods, regulations and techniques utilized for reassessment of seismic safety of operating NPPs and promoting safety; investigation of earthquake hazards; development of concepts for creating the seismic safety location of earthquake warning system; determination of dynamic features of systems and facilities determined by the concept, and preliminary evaluation of the seismic safety

  13. Evaluation of seismic characteristics and structural integrity for the cabinet of HANARO seismic monitoring analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Yoon, Doo Byung

    2003-06-01

    The HANARO SMAS(Seismic Monitoring Analysis System) is classified as Non-Nuclear Safety(NNS), seismic category I, and quality class T. It is required that this system can perform required functions, which are to preserve its structural integrity during and after an OBE or SSE. In this work, the structural integrity and seismic characteristics of the cabinet of the newly developed SMAS have been estimated. The most parts of the cabinet are identically designed with those of Yonggwhang and Gori Nuclear Power Plants(NPPs), unit 1 that successfully completed the required seismic qualification tests. The structure of the cabinet of the SMAS is manufactured by the manufacturer of the cabinet of Yonggwhang and Gori NPPs. To evaluate the seismic characteristics of the SMAS, the RRS(Required Response Spectra) of the newly developed cabinet are compared with those of Yonggwhang and Gori NPPs, unit 1. In addition, natural frequencies of the cabinet of HANARO, Yonggwhang, and Gori NPPs were measured for the comparison of the seismic characteristics of the installed cabinets. In case of HANARO, the bottom of the cabinet is welded to the base plate. The base plate is fixed to the concrete foundation by using anchor bolts. For the evaluation of the structural integrity of the welding parts and the anchor bolts, the maximum stresses and forces of the welding parts and the anchor bolts due to seismic loading are estimated. The analysis results show that maximum stresses and forces are less than the allowable limits. This new SMAS is operating at HANARO instrument room to acquire and analyze the signal of earthquake.

  14. New seismic sources parameterization in El Salvador. Implications to seismic hazard.

    OpenAIRE

    Alonso-Henar, Jorge; Staller, A.; Martínez Díaz, José J.; Benito, Belén; Álvarez Gómez, José Antonio; Canora Catalán, Carolina

    2014-01-01

    El Salvador is located at the pacific active margin of Central America, here, the subduction of the Cocos Plate under the Caribbean Plate at a rate of 80 mm/yr is the main seismic source. Although the seismic sources located in the Central American Volcanic Arc have been responsible for some of the most damaging earthquakes in El Salvador. The El Salvador Fault Zone is the main geological structure in El Salvador and accommodates 14 mm/yr of horizontal displacement between the Caribbean Plate...

  15. Induced seismicity in Carbon and Emery counties, Utah

    Science.gov (United States)

    Brown, Megan R. M.

    Utah is one of the top producers of oil and natural gas in the United States. Over the past 18 years, more than 4.2 billion gallons of wastewater from the petroleum industry have been injected into the Navajo Sandstone, Kayenta Formation, and Wingate Sandstone in two areas in Carbon and Emery County, Utah, where seismicity has increased during the same period. In this study, I investigated whether or not wastewater injection is related to the increased seismicity. Previous studies have attributed all of the seismicity in central Utah to coal mining activity. I found that water injection might be a more important cause. In the coal mining area, seismicity rate increased significantly 1-5 years following the commencement of wastewater injection. The increased seismicity consists almost entirely of earthquakes with magnitudes of less than 3, and is localized in areas seismically active prior to the injection. I have established the spatiotemporal correlations between the coal mining activities, the wastewater injection, and the increased seismicity. I used simple groundwater models to estimate the change in pore pressure and evaluate the observed time gap between the start of injection and the onset of the increased seismicity in the areas surrounding the injection wells. To ascertain that the increased seismicity is not fluctuation of background seismicity, I analyzed the magnitude-frequency relation of these earthquakes and found a clear increase in the b-value following the wastewater injection. I conclude that the marked increase of seismicity rate in central Utah is induced by both mining activity and wastewater injection, which raised pore pressure along pre-existing faults.

  16. Machine medical ethics

    CERN Document Server

    Pontier, Matthijs

    2015-01-01

    The essays in this book, written by researchers from both humanities and sciences, describe various theoretical and experimental approaches to adding medical ethics to a machine in medical settings. Medical machines are in close proximity with human beings, and getting closer: with patients who are in vulnerable states of health, who have disabilities of various kinds, with the very young or very old, and with medical professionals. In such contexts, machines are undertaking important medical tasks that require emotional sensitivity, knowledge of medical codes, human dignity, and privacy. As machine technology advances, ethical concerns become more urgent: should medical machines be programmed to follow a code of medical ethics? What theory or theories should constrain medical machine conduct? What design features are required? Should machines share responsibility with humans for the ethical consequences of medical actions? How ought clinical relationships involving machines to be modeled? Is a capacity for e...

  17. Research on high level radioactive waste repository seismic design criteria

    International Nuclear Information System (INIS)

    Jing Xu

    2012-01-01

    Review seismic hazard analysis principle and method in site suitable assessment process of Yucca Mountain Project, and seismic design criteria and seismic design basis in primary design process. Demonstrated spatial character of seismic hazard by calculated regional seismic hazard map. Contrasted different level seismic design basis to show their differences and relation. Discussed seismic design criteria for preclosure phrase of high level waste repository and preference goal under beyond design basis ground motion. (author)

  18. Humanizing machines: Anthropomorphization of slot machines increases gambling.

    Science.gov (United States)

    Riva, Paolo; Sacchi, Simona; Brambilla, Marco

    2015-12-01

    Do people gamble more on slot machines if they think that they are playing against humanlike minds rather than mathematical algorithms? Research has shown that people have a strong cognitive tendency to imbue humanlike mental states to nonhuman entities (i.e., anthropomorphism). The present research tested whether anthropomorphizing slot machines would increase gambling. Four studies manipulated slot machine anthropomorphization and found that exposing people to an anthropomorphized description of a slot machine increased gambling behavior and reduced gambling outcomes. Such findings emerged using tasks that focused on gambling behavior (Studies 1 to 3) as well as in experimental paradigms that included gambling outcomes (Studies 2 to 4). We found that gambling outcomes decrease because participants primed with the anthropomorphic slot machine gambled more (Study 4). Furthermore, we found that high-arousal positive emotions (e.g., feeling excited) played a role in the effect of anthropomorphism on gambling behavior (Studies 3 and 4). Our research indicates that the psychological process of gambling-machine anthropomorphism can be advantageous for the gaming industry; however, this may come at great expense for gamblers' (and their families') economic resources and psychological well-being. (c) 2015 APA, all rights reserved).

  19. Frame Optimization Analysis for Bathing Trolley%浸洗台车结构设计的优化分析

    Institute of Scientific and Technical Information of China (English)

    陈玮; 芦宏斌

    2011-01-01

    Objective To develop a special equipment that can be used for cleaning and disinfection of nonhuman primates. Methods With CAD/CAE technology, three-dimensional modeling of the main framework was built, and the load and restriction of the model support were reduced by CAE calculation in order to get optimized result. Results Through the optimization of the main framework, the overall weight was reduced, and force bearing points of the support structure were distributed reasonably. Conclusion The bathing trolley, being novel, easy to operate and clean, improves the experimental animal management and occupational health protection.%目的:研制一种用于非人灵长类动物清洗消毒的专用设备.方法:利用CAD/CAE技术,针对主体框架进行CAD建模并简化主要承力部件载荷和约束的施加,进行CAE强度分析计算,以结构布局合理为优化目标.结果:减轻了整体质量,合理设计布控了支撑结构承力点.结论:该浸洗台车设计新颖、操作方便、易于清洗消毒,提高了实验动物管理和职业卫生防护水平,具有良好的推广应用前景.

  20. Horizontal Acoustic Barriers for Protection from Seismic Waves

    Directory of Open Access Journals (Sweden)

    Sergey V. Kuznetsov

    2011-01-01

    Full Text Available The basic idea of a seismic barrier is to protect an area occupied by a building or a group of buildings from seismic waves. Depending on nature of seismic waves that are most probable in a specific region, different kinds of seismic barriers can be suggested. Herein, we consider a kind of a seismic barrier that represents a relatively thin surface layer that prevents surface seismic waves from propagating. The ideas for these barriers are based on one Chadwick's result concerning nonpropagation condition for Rayleigh waves in a clamped half-space, and Love's theorem that describes condition of nonexistence for Love waves. The numerical simulations reveal that to be effective the length of the horizontal barriers should be comparable to the typical wavelength.

  1. A linear motor as seismic horizontal vibrator

    NARCIS (Netherlands)

    Drijkoningen, G.; Veltman, A.; Hendrix, W.H.A.; Brouwer, J.; Hemstede, A.

    2006-01-01

    In this paper we propose to use the concept of linear synchronous motors to act as a seismic shear-wave vibratory source. We show that a linear motor, even with a design that is not focussed on application of seismic surveying, gives seismic records that are convincing and comparable with an

  2. Adaptive prediction applied to seismic event detection

    International Nuclear Information System (INIS)

    Clark, G.A.; Rodgers, P.W.

    1981-01-01

    Adaptive prediction was applied to the problem of detecting small seismic events in microseismic background noise. The Widrow-Hoff LMS adaptive filter used in a prediction configuration is compared with two standard seismic filters as an onset indicator. Examples demonstrate the technique's usefulness with both synthetic and actual seismic data

  3. Approaches that use seismic hazard results to address topics of nuclear power plant seismic safety, with application to the Charleston earthquake issue

    International Nuclear Information System (INIS)

    Sewell, R.T.; McGuire, R.K.; Toro, G.R.; Stepp, J.C.; Cornell, C.A.

    1990-01-01

    Plant seismic safety indicators include seismic hazard at the SSE (safe shut-down earthquake) acceleration, seismic margin, reliability against core damage, and reliability against offsite consequences. This work examines the key role of hazard analysis in evaluating these indicators and in making rational decisions regarding plant safety. The paper outlines approaches that use seismic hazard results as a basis for plant seismic safety evaluation and applies one of these approaches to the Charleston earthquake issue. This approach compares seismic hazard results that account for the Charleston tectonic interpretation, using the EPRI-Seismicity Owners Group (SOG) methodology, with hazard results that are consistent with historical tectonic interpretations accepted in regulation. Based on hazard results for a set of 21 eastern U.S. nuclear power plant sites, the comparison shows that no systematic 'plant-to-plant' increase in hazard accompanies the Charleston hypothesis; differences in mean hazards for the two interpretations are generally insignificant relative to current uncertainties in seismic hazard. (orig.)

  4. Correlation-based seismic velocity inversion

    NARCIS (Netherlands)

    Van Leeuwen, T.

    2010-01-01

    Most of our knowledge of the subsurface comes from the measurement of quantities that are indirectly related to the earth’s structure. Examples are seismic waves, gravity and electromagnetic waves. We consider the use of seismic waves for inference of structural information on an exploration scale.

  5. Post-seismic velocity changes following the 2010 Mw 7.1 Darfield earthquake, New Zealand, revealed by ambient seismic field analysis

    Science.gov (United States)

    Heckels, R. EG; Savage, M. K.; Townend, J.

    2018-05-01

    Quantifying seismic velocity changes following large earthquakes can provide insights into fault healing and reloading processes. This study presents temporal velocity changes detected following the 2010 September Mw 7.1 Darfield event in Canterbury, New Zealand. We use continuous waveform data from several temporary seismic networks lying on and surrounding the Greendale Fault, with a maximum interstation distance of 156 km. Nine-component, day-long Green's functions were computed for frequencies between 0.1 and 1.0 Hz for continuous seismic records from immediately after the 2010 September 04 earthquake until 2011 January 10. Using the moving-window cross-spectral method, seismic velocity changes were calculated. Over the study period, an increase in seismic velocity of 0.14 ± 0.04 per cent was determined near the Greendale Fault, providing a new constraint on post-seismic relaxation rates in the region. A depth analysis further showed that velocity changes were confined to the uppermost 5 km of the subsurface. We attribute the observed changes to post-seismic relaxation via crack healing of the Greendale Fault and throughout the surrounding region.

  6. Design response spectra-compliant real and synthetic GMS for seismic analysis of seismically isolated nuclear reactor containment building

    Directory of Open Access Journals (Sweden)

    Ahmer Ali

    2017-06-01

    Full Text Available Due to the severe impacts of recent earthquakes, the use of seismic isolation is paramount for the safety of nuclear structures. The diversity observed in seismic events demands ongoing research to analyze the devastating attributes involved, and hence to enhance the sustainability of base-isolated nuclear power plants. This study reports the seismic performance of a seismically-isolated nuclear reactor containment building (NRCB under strong short-period ground motions (SPGMs and long-period ground motions (LPGMs. The United States Nuclear Regulatory Commission-based design response spectrum for the seismic design of nuclear power plants is stipulated as the reference spectrum for ground motion selection. Within the period range(s of interest, the spectral matching of selected records with the target spectrum is ensured using the spectral-compatibility approach. NRC-compliant SPGMs and LPGMs from the mega-thrust Tohoku earthquake are used to obtain the structural response of the base-isolated NRCB. To account for the lack of earthquakes in low-to-moderate seismicity zones and the gap in the artificial synthesis of long-period records, wavelet-decomposition based autoregressive moving average modeling for artificial generation of real ground motions is performed. Based on analysis results from real and simulated SPGMs versus LPGMs, the performance of NRCBs is discussed with suggestions for future research and seismic provisions.

  7. Design response spectra-compliant real and synthetic GMS for seismic analysis of seismically isolated nuclear reactor containment building

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Ahmer [ENVICO Consultants Co. Ltd., Seoul (Korea, Republic of); Abu-Hayah, Nadin; Kim, Doo Kie [Civil and Environmental Engineering, Kunsan National University, Gunsan (Korea, Republic of); Cho, Sung Gook [Innose Tech Co., Ltd., Incheon (Korea, Republic of)

    2017-06-15

    Due to the severe impacts of recent earthquakes, the use of seismic isolation is paramount for the safety of nuclear structures. The diversity observed in seismic events demands ongoing research to analyze the devastating attributes involved, and hence to enhance the sustainability of base-isolated nuclear power plants. This study reports the seismic performance of a seismically-isolated nuclear reactor containment building (NRCB) under strong short-period ground motions (SPGMs) and long-period ground motions (LPGMs). The United States Nuclear Regulatory Commission-based design response spectrum for the seismic design of nuclear power plants is stipulated as the reference spectrum for ground motion selection. Within the period range(s) of interest, the spectral matching of selected records with the target spectrum is ensured using the spectral-compatibility approach. NRC-compliant SPGMs and LPGMs from the mega-thrust Tohoku earthquake are used to obtain the structural response of the base-isolated NRCB. To account for the lack of earthquakes in low-to-moderate seismicity zones and the gap in the artificial synthesis of long-period records, wavelet-decomposition based autoregressive moving average modeling for artificial generation of real ground motions is performed. Based on analysis results from real and simulated SPGMs versus LPGMs, the performance of NRCBs is discussed with suggestions for future research and seismic provisions.

  8. Seismic motions from project Rulison

    Energy Technology Data Exchange (ETDEWEB)

    Loux, P C [Environmental Research Corp., Alexandria, VA (United States)

    1970-05-15

    In the range from a few to a few hundred km, seismic measurements from the Rulison event are shown and compared with experimentally and analytically derived pre-event estimates. Seismograms, peak accelerations, and response spectra are given along with a description of the associated geologic environment. Techniques used for the pre-event estimates are identified with emphasis on supportive data and on Rulison results. Of particular interest is the close-in seismic frequency content which is expected to contain stronger high frequency components. This higher frequency content translates into stronger accelerations within the first tens of km, which in turn affect safety preparations. Additionally, the local geologic structure at nearby population centers must be considered. Pre-event reverse profile refraction surveys are used to delineate the geology at Rifle, Rulison, Grand Valley, and other sites. The geologic parameters are then used as input to seismic amplification models which deliver estimates of local resonant frequencies. Prediction of such resonances allows improved safety assurance against seismic effects hazards. (author)

  9. Sensitivity Analysis on Elbow Piping Components in Seismically Isolated NPP under Seismic Loading

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Hee Kun; Hahm, Dae Gi; Kim, Min Kyu [KAERI, Daejeon (Korea, Republic of); Jeon, Bub Gyu; Kim, Nam Sik [Pusan National University, Busan (Korea, Republic of)

    2016-05-15

    In this study, the FE model is verified using specimen test results and simulation with parameter variations are conducted. Effective parameters will randomly sampled and used as input values for simulations to be applied to the fragility analysis. pipelines are representative of them because they could undergo larger displacements when they are supported on both isolated and non-isolated structures simultaneously. Especially elbows are critical components of pipes under severed loading conditions such as earthquake action because strain is accumulated on them during the repeated bending of the pipe. Therefore, seismic performance of pipe elbow components should be examined thoroughly based on the fragility analysis. Fragility assessment of interface pipe should take different sources of uncertainty into account. However, selection of important sources and repeated tests with many random input values are very time consuming and expensive, so numerical analysis is commonly used. In the present study, finite element (FE) model of elbow component will be validated using the dynamic test results of elbow components. Using the verified model, sensitivity analysis will be implemented as a preliminary process of seismic fragility of piping system. Several important input parameters are selected and how the uncertainty of them are apportioned to the uncertainty of the elbow response is to be studied. Piping elbows are critical components under cyclic loading conditions as they are subjected large displacement. In a seismically isolated NPP, seismic capacity of piping system should be evaluated with caution. Seismic fragility assessment preliminarily needs parameter sensitivity analysis about the output of interest with different input parameter values.

  10. Code-expanded radio access protocol for machine-to-machine communications

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2013-01-01

    The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated b...... subframes and orthogonal preambles, the amount of available contention resources is drastically increased, enabling the massive support of Machine-Type Communication users that is beyond the reach of current systems.......The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated...... by the random access method employed in LTE, which significantly increases the amount of contention resources without increasing the system resources, such as contention subframes and preambles. This is accomplished by a logical, rather than physical, extension of the access method in which the available system...

  11. Seismic anisotropies of the Songshugou peridotites (Qinling orogen, central China) and their seismic implications

    Science.gov (United States)

    Cao, Yi; Jung, Haemyeong; Song, Shuguang

    2018-01-01

    Though extensively studied, the roles of olivine crystal preferred orientations (CPOs or fabrics) in affecting the seismic anisotropies in the Earth's upper mantle are rather complicated and still not fully known. In this study, we attempted to address this issue by analyzing the seismic anisotropies [e.g., P-wave anisotropy (AVp), S-wave polarization anisotropy (AVs), radial anisotropy (ξ), and Rayleigh wave anisotropy (G)] of the Songshugou peridotites (dunite dominated) in the Qinling orogen in central China, based on our previously reported olivine CPOs. The seismic anisotropy patterns of olivine aggregates in our studied samples are well consistent with the prediction for their olivine CPO types; and the magnitude of seismic anisotropies shows a striking positive correlation with equilibrium pressure and temperature (P-T) conditions. Significant reductions of seismic anisotropies (AVp, max. AVs, and G) are observed in porphyroclastic dunite compared to coarse- and fine-grained dunites, as the results of olivine CPO transition (from A-/D-type in coarse-grained dunite, through AG-type-like in porphyroclastic dunite, to B-type-like in fine-grained dunite) and strength variation (weakening: A-/D-type → AG-type-like; strengthening: AG-type-like → B-type-like) during dynamic recrystallization. The transition of olivine CPOs from A-/D-type to B-/AG-type-like in the forearc mantle may weaken the seismic anisotropies and deviate the fast velocity direction and the fast S-wave polarization direction from trench-perpendicular to trench-oblique direction with the cooling and aging of forearc mantle. Depending on the size and distribution of the peridotite body such as the Songshugou peridotites, B- and AG-type-like olivine CPOs can be an additional (despite minor) local contributor to the orogen-parallel fast velocity direction and fast shear-wave polarization direction in the orogenic crust such as in the Songshugou area in Qinling orogen.

  12. Worldwide Assessment of the Status of Seismic Zonation, Fourth International Forum on Seismic Zonation, Proceedings

    Science.gov (United States)

    Hays, W.W.

    1994-01-01

    We are pleased to provide you with information developed for the Fourth International Forum on Seismic Zonation which will be convened in two locations year in conjunction two major international meetings. The objectives are: 1) to assess the status of seismic zonation in every country of the world, 2) to evaluate the reasons for advances and new initiatives, and 3) to foster continued cooperation. Seismic zonation is the process that leads to risk reduction and sustainability of new development. It is based on the division of a geographic region into smaller areas or zones on the basis of an integrated assessment of the hazard, built, and policy environments of the region. Seismic zonation depends on hazard mapping performed on national/regional, subregional, and urban (i.e., microzonation) scales depending on the particular application. We gratefully acknowledge the written communications of many professionals who responded to our request for information. Also, we acknowledge the use of information contained in five valuable reports (see directories in the Appendices for information on where to obtain copies of the reports): 1. United Nations, 1990, Cooperative Project for Seismic Risk Reduction in the Mediterranean Region (SEISMED), proceedings, Office of the United Nations Disaster Relief Coordinator, Geneva, Switzerland, 3 vols. (Franco Maranzana -

  13. Adaptive prediction applied to seismic event detection

    Energy Technology Data Exchange (ETDEWEB)

    Clark, G.A.; Rodgers, P.W.

    1981-09-01

    Adaptive prediction was applied to the problem of detecting small seismic events in microseismic background noise. The Widrow-Hoff LMS adaptive filter used in a prediction configuration is compared with two standard seismic filters as an onset indicator. Examples demonstrate the technique's usefulness with both synthetic and actual seismic data.

  14. Earthquake source studies and seismic imaging in Alaska

    Science.gov (United States)

    Tape, C.; Silwal, V.

    2015-12-01

    Alaska is one of the world's most seismically and tectonically active regions. Its enhanced seismicity, including slab seismicity down to 180 km, provides opportunities (1) to characterize pervasive crustal faulting and slab deformation through the estimation of moment tensors and (2) to image subsurface structures to help understand the tectonic evolution of Alaska. Most previous studies of earthquakes and seismic imaging in Alaska have emphasized earthquake locations and body-wave travel-time tomography. In the past decade, catalogs of seismic moment tensors have been established, while seismic surface waves, active-source data, and potential field data have been used to improve models of seismic structure. We have developed moment tensor catalogs in the regions of two of the largest sedimentary basins in Alaska: Cook Inlet forearc basin, west of Anchorage, and Nenana basin, west of Fairbanks. Our moment tensor solutions near Nenana basin suggest a transtensional tectonic setting, with the basin developing in a stepover of a left-lateral strike-slip fault system. We explore the effects of seismic wave propagation from point-source and finite-source earthquake models by performing three-dimensional wavefield simulations using seismic velocity models that include major sedimentary basins. We will use our catalog of moment tensors within an adjoint-based, iterative inversion to improve the three-dimensional tomographic model of Alaska.

  15. Development of seismic tomography software for hybrid supercomputers

    Science.gov (United States)

    Nikitin, Alexandr; Serdyukov, Alexandr; Duchkov, Anton

    2015-04-01

    Seismic tomography is a technique used for computing velocity model of geologic structure from first arrival travel times of seismic waves. The technique is used in processing of regional and global seismic data, in seismic exploration for prospecting and exploration of mineral and hydrocarbon deposits, and in seismic engineering for monitoring the condition of engineering structures and the surrounding host medium. As a consequence of development of seismic monitoring systems and increasing volume of seismic data, there is a growing need for new, more effective computational algorithms for use in seismic tomography applications with improved performance, accuracy and resolution. To achieve this goal, it is necessary to use modern high performance computing systems, such as supercomputers with hybrid architecture that use not only CPUs, but also accelerators and co-processors for computation. The goal of this research is the development of parallel seismic tomography algorithms and software package for such systems, to be used in processing of large volumes of seismic data (hundreds of gigabytes and more). These algorithms and software package will be optimized for the most common computing devices used in modern hybrid supercomputers, such as Intel Xeon CPUs, NVIDIA Tesla accelerators and Intel Xeon Phi co-processors. In this work, the following general scheme of seismic tomography is utilized. Using the eikonal equation solver, arrival times of seismic waves are computed based on assumed velocity model of geologic structure being analyzed. In order to solve the linearized inverse problem, tomographic matrix is computed that connects model adjustments with travel time residuals, and the resulting system of linear equations is regularized and solved to adjust the model. The effectiveness of parallel implementations of existing algorithms on target architectures is considered. During the first stage of this work, algorithms were developed for execution on

  16. Seismic resistance of WWER equipment (systematization and generalization)

    International Nuclear Information System (INIS)

    Kaznovski, S.; Chechenov, H.

    1999-01-01

    Within the scope of the contract with IAEA, calculational and experimental investigations of equipment seismic resistance were carried out. Systematic seismic inspection was conducted for 21 WWER type reactors in Armenia, Bulgaria, Russia, Slovakia and Ukraine. On the base of generalisation of extensive real data accumulated during inspection of equipment seismic resistance at different WWER-type NPPs the classification of seismic instability reasons and working out of generalised recommendations were carried out. It gives the possibility to specialists in many cases to expose the seismic insufficiency of equipment and to choose the suitable measures without laborious experimental investigations, tests, and calculations

  17. SEG Advances in Rotational Seismic Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, Robert; Laughlin, Darren; Brune, Bob

    2016-10-17

    Significant advancements in the development of sensors to enable rotational seismic measurements have been achieved. Prototypes are available now to support experiments that help validate the utility of rotational seismic measurements.

  18. Seismic imaging of sandbox experiments – laboratory hardware setup and first reflection seismic sections

    Directory of Open Access Journals (Sweden)

    C. M. Krawczyk

    2013-02-01

    Full Text Available With the study and technical development introduced here, we combine analogue sandbox simulation techniques with seismic physical modelling of sandbox models. For that purpose, we designed and developed a new mini-seismic facility for laboratory use, comprising a seismic tank, a PC-driven control unit, a positioning system, and piezoelectric transducers used here for the first time in an array mode. To assess the possibilities and limits of seismic imaging of small-scale structures in sandbox models, different geometry setups were tested in the first 2-D experiments that also tested the proper functioning of the device and studied the seismo-elastic properties of the granular media used. Simple two-layer models of different materials and layer thicknesses as well as a more complex model comprising channels and shear zones were tested using different acquisition geometries and signal properties. We suggest using well sorted and well rounded grains with little surface roughness (glass beads. Source receiver-offsets less than 14 cm for imaging structures as small as 2.0–1.5 mm size have proven feasible. This is the best compromise between wide beam and high energy output, and is applicable with a consistent waveform. Resolution of the interfaces of layers of granular materials depends on the interface preparation rather than on the material itself. Flat grading of interfaces and powder coverage yields the clearest interface reflections. Finally, sandbox seismic sections provide images of high quality showing constant thickness layers as well as predefined channel structures and indications of the fault traces from shear zones. Since these were artificially introduced in our test models, they can be regarded as zones of disturbance rather than tectonic shear zones characterized by decompaction. The multiple-offset surveying introduced here, improves the quality with respect to S / N ratio and source signature even more; the maximum depth

  19. NRC Seismic Design Margins Program Plan

    International Nuclear Information System (INIS)

    Cummings, G.E.; Johnson, J.J.; Budnitz, R.J.

    1985-08-01

    Recent studies estimate that seismically induced core melt comes mainly from earthquakes in the peak ground acceleration range from 2 to 4 times the safe shutdown earthquake (SSE) acceleration used in plant design. However, from the licensing perspective of the US Nuclear Regulatory Commission, there is a continuing need for consideration of the inherent quantitative seismic margins because of, among other things, the changing perceptions of the seismic hazard. This paper discusses a Seismic Design Margins Program Plan, developed under the auspices of the US NRC, that provides the technical basis for assessing the significance of design margins in terms of overall plant safety. The Plan will also identify potential weaknesses that might have to be addressed, and will recommend technical methods for assessing margins at existing plants. For the purposes of this program, a general definition of seismic design margin is expressed in terms of how much larger that the design basis earthquake an earthquake must be to compromise plant safety. In this context, margin needs to be determined at the plant, system/function, structure, and component levels. 14 refs., 1 fig

  20. Probabilistic Seismic Hazard Assessment for Iraq

    Energy Technology Data Exchange (ETDEWEB)

    Onur, Tuna [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gok, Rengin [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Abdulnaby, Wathiq [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shakir, Ammar M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mahdi, Hanan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Numan, Nazar M.S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Al-Shukri, Haydar [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chlaib, Hussein K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ameen, Taher H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Abd, Najah A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-05-06

    Probabilistic Seismic Hazard Assessments (PSHA) form the basis for most contemporary seismic provisions in building codes around the world. The current building code of Iraq was published in 1997. An update to this edition is in the process of being released. However, there are no national PSHA studies in Iraq for the new building code to refer to for seismic loading in terms of spectral accelerations. As an interim solution, the new draft building code was considering to refer to PSHA results produced in the late 1990s as part of the Global Seismic Hazard Assessment Program (GSHAP; Giardini et al., 1999). However these results are: a) more than 15 years outdated, b) PGA-based only, necessitating rough conversion factors to calculate spectral accelerations at 0.3s and 1.0s for seismic design, and c) at a probability level of 10% chance of exceedance in 50 years, not the 2% that the building code requires. Hence there is a pressing need for a new, updated PSHA for Iraq.

  1. Nuclear fuel assembly seismic amplitude limiter

    International Nuclear Information System (INIS)

    Anthony, A.J.

    1977-01-01

    The ability of a nuclear reactor to withstand high seismic loading is enhanced by including, on each fuel assembly, at least one seismic grid which reduces the magnitude of the possible lateral deflection of the individual fuel elements and the entire fuel assembly. The reduction in possible deflection minimizes the possibility of impact of the spacer grids of one fuel assembly on those of an adjacent fuel assembly and reduces the magnitude of forces associated with any such impact thereby minimizing the possibility of fuel assembly damage as a result of high seismic loading. The seismic grid is mounted from the fuel assembly guide tubes, has greater external dimensions when compared to the fuel assembly spacer grids and normally does not support or otherwise contact the fuel elements. The reduction in possible deflection is achieved through reduction of the clearance between adjacent fuel assemblies made possible by the use in the seismic grid of a high strength material characterized by favorable thermal expansion characteristics and minimal irradiation induced expansion

  2. A GIS approach to seismic risk assessment with an application to mining-related seismicity in Johannesburg, South Africa

    Science.gov (United States)

    Liebenberg, Keagen; Smit, Ansie; Coetzee, Serena; Kijko, Andrzej

    2017-08-01

    The majority of seismic activity in South Africa is related to extensive mining operations, usually in close proximity to densely populated areas where a relatively weak seismic event could cause damage. Despite a significant decrease in mining operations in the Witwatersrand area, the number of seismic events appears to be increasing and is attributed to the acid mine drainage problem. The increased seismicity is raising concern amongst disaster management centres and in the insurance industry. A better understanding is required of the vulnerability and the size of the potential loss of people and infrastructure in densely populated Johannesburg and its surrounding areas. Results of a deterministic seismic risk, vulnerability, and loss assessment are presented by making use of a geographic information system (GIS). The results illustrate the benefits of using GIS and contribute to a better understanding of the risk, which can assist in improving disaster preparedness.

  3. Third Quarter Hanford Seismic Report for Fiscal Year 2005

    Energy Technology Data Exchange (ETDEWEB)

    Reidel, Steve P.; Rohay, Alan C.; Hartshorn, Donald C.; Clayton, Ray E.; Sweeney, Mark D.

    2005-09-01

    Hanford Seismic Monitoring provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network for the U.S. Department of Energy and its contractors. Hanford Seismic Monitoring also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compiled, archived, and published for use by the Hanford Site for waste management, Natural Phenomena Hazards assessments, and engineering design and construction. In addition, the seismic monitoring organization works with the Hanford Site Emergency Services Organization to provide assistance in the event of a significant earthquake on the Hanford Site. The Hanford Seismic Network and the Eastern Washington Regional Network consist of 41 individual sensor sites and 15 radio relay sites maintained by the Hanford Seismic Monitoring staff. For the Hanford Seismic Network, there were 337 triggers during the third quarter of fiscal year 2005. Of these triggers, 20 were earthquakes within the Hanford Seismic Network. The largest earthquake within the Hanford Seismic Network was a magnitude 1.3 event May 25 near Vantage, Washington. During the third quarter, stratigraphically 17 (85%) events occurred in the Columbia River basalt (approximately 0-5 km), no events in the pre-basalt sediments (approximately 5-10 km), and three (15%) in the crystalline basement (approximately 10-25 km). During the first quarter, geographically five (20%) earthquakes occurred in swarm areas, 10 (50%) earthquakes were associated with a major geologic structure, and 5 (25%) were classified as random events.

  4. Seismic data processing for domestic seismic survey over the continental shelf of Korea using the Geobit

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jin Yong [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    The `Geobit`, a new seismic data processing software introduced by the Korea Institute of Geology, Mining and Materials recently, is the token of the achievement for the development of technology in the oil exploration over the Korean continental shelf. In comparison with the foreign seismic data processing systems previously used in Korea, the Geobit system has some advanced facilities; it provides an interactive mode which makes the seismic processing easier and has the user-friendly programs which allow the construction of a job control file simpler. Most of all, the Geobit can be run with many computer hardware systems, from PC to supercomputer. The current version of the Geobit can take care of the two-dimensional multi-channel seismic data and is open to the public for an education tool and a research purpose. To demonstrate the ability of the Geobit, a multi-channel field data acquired in the domestic continental shelf over the Yellow Sea in 1970 has been selected and processed with standard seismic data processing techniques. In this report, the Geobit job files and the corresponding results for the construction of a stack are provided. (author). 8 refs., 14 figs., 1 tab.

  5. Status report on seismic re-evaluation

    International Nuclear Information System (INIS)

    1998-01-01

    In May 1997, a meeting of the PWG 3 Sub Group on the Seismic Behaviour of Structures agreed several priority objectives, of which one was the production of a status report on seismic re-evaluation. Seismic re-evaluation is identified as the process of carrying out a re-assessment of the safety of existing nuclear power plants for a specified seismic hazard. This may be necessary when no seismic hazard was considered in the original design of the plant, the relevant codes and regulations have been revised, the seismic hazard for the site has been re-assessed or there is a need to assess the capacity of the plant for severe accident conditions and behaviour beyond the design basis. Re-evaluation may also be necessary to resolve an issue, or to assess the impact of new findings or knowledge. A questionnaire on the subject was issued to all members of the Seismic Sub Group in the summer of 1997, and responses to the questionnaire had been received from most members by the end of 1997. This report is based on the responses to the questionnaire, together with comment and discussion within the group. The questionnaire covered the following main topics of interest in relation to seismic re-evaluation: General and Legislative Framework, Overall Approach, Input Definition and Analysis Methods, Scope of Plant and Assessment of As-built Situation, Assessment criteria, Outcome of Re-evaluations, Research. The responses to the questionnaire have been collated and reviewed with the objective of comparing current practice in the field of seismic re-evaluation in member countries, and a number of important points have been identified in relation to the position of seismic re-evaluation in the nuclear power industry throughout the world. It is evident that seismic re-evaluation is a relatively mature process that has been developing for some time, with most countries adopting similar practices, often based on principles which have been developed in the US nuclear industry. Seismic

  6. Seismic assessment and upgrading of Paks nuclear power plant

    International Nuclear Information System (INIS)

    Tamas, K.

    2001-01-01

    A comprehensive programme for seismic assessment and upgrading is currently in progress at Hungary's Paks NPP. The re-evaluation of the site seismic hazard had been already completed. The technology of safe shut down and heat removal is established and the systems and structures relevant for seismic safety are identified. A seismic instrumentation is installed. The pre-earthquake preparedness and post-earthquake actions are elaborated. The methods for seismic capacity assessment are selected. The seismic capacity evaluation and the design of upgrading measures are currently in progress. The easy to perform upgrading covering the most urgent measures had been already performed. (author)

  7. Simple machines

    CERN Document Server

    Graybill, George

    2007-01-01

    Just how simple are simple machines? With our ready-to-use resource, they are simple to teach and easy to learn! Chocked full of information and activities, we begin with a look at force, motion and work, and examples of simple machines in daily life are given. With this background, we move on to different kinds of simple machines including: Levers, Inclined Planes, Wedges, Screws, Pulleys, and Wheels and Axles. An exploration of some compound machines follows, such as the can opener. Our resource is a real time-saver as all the reading passages, student activities are provided. Presented in s

  8. Seismic activity maps for the Armenian Highlands

    Energy Technology Data Exchange (ETDEWEB)

    Karapetyan, N.K.; Manukyan, Zh.O.

    1976-01-01

    Seismic activity maps for the periods 1952 to 1967 and 1952 to 1968 were compiled for the Armenian Highlands in order to study the spatial distribution of earthquake recurrence and to construct maps in isolines of seismic activity. Diagrams are presented illustrating such seismic activity maps for the indicated periods. 4 references, 3 figures, 1 table.

  9. Oklahoma seismic network

    International Nuclear Information System (INIS)

    Luza, K.V.; Lawson, J.E. Jr.; Univ. of Oklahoma, Norman, OK

    1993-07-01

    The US Nuclear Regulatory Commission has established rigorous guidelines that must be adhered to before a permit to construct a nuclear-power plant is granted to an applicant. Local as well as regional seismicity and structural relationships play an integral role in the final design criteria for nuclear power plants. The existing historical record of seismicity is inadequate in a number of areas of the Midcontinent region because of the lack of instrumentation and (or) the sensitivity of the instruments deployed to monitor earthquake events. The Nemaha Uplift/Midcontinent Geophysical Anomaly is one of five principal areas east of the Rocky Mountain front that has a moderately high seismic-risk classification. The Nemaha uplift, which is common to the states of Oklahoma, Kansas, and Nebraska, is approximately 415 miles long and 12-14 miles wide. The Midcontinent Geophysical Anomaly extends southward from Minnesota across Iowa and the southeastern corner of Nebraska and probably terminates in central Kansas. A number of moderate-sized earthquakes--magnitude 5 or greater--have occurred along or west of the Nemaha uplift. The Oklahoma Geological Survey, in cooperation with the geological surveys of Kansas, Nebraska, and Iowa, conducted a 5-year investigation of the seismicity and tectonic relationships of the Nemaha uplift and associated geologic features in the Midcontinent. This investigation was intended to provide data to be used to design nuclear-power plants. However, the information is also being used to design better large-scale structures, such as dams and high-use buildings, and to provide the necessary data to evaluate earthquake-insurance rates in the Midcontinent

  10. Seismic safety margin assessment program (Annual safety research report, JFY 2010)

    International Nuclear Information System (INIS)

    Suzuki, Kenichi; Iijima, Toru; Inagaki, Masakatsu; Taoka, Hideto; Hidaka, Shinjiro

    2011-01-01

    Seismic capacity test data, analysis method and evaluation code provided by Seismic Safety Margin Assessment Program have been utilized for the support of seismic back-check evaluation of existing plants. The summary of the program in 2010 is as follows. 1. Component seismic capacity test and quantitative seismic capacity evaluation. Many seismic capacity tests of various snubbers were conducted and quantitative seismic capacities were evaluated. One of the emergency diesel generator partial-model seismic capacity tests was conducted and quantitative seismic capacity was evaluated. Some of the analytical evaluations of piping-system seismic capacities were conducted. 2. Analysis method for minute evaluation of component seismic response. The difference of seismic response of large components such as primary containment vessel and reactor pressure vessel when they were coupled with 3-dimensional FEM building model or 1-dimensional lumped mass building model, was quantitatively evaluated. 3. Evaluation code for quantitative evaluation of seismic safety margin of systems, structures and components. As the example, quantitative evaluation of seismic safety margin of systems, structures and components were conducted for the reference plant. (author)

  11. Machine performance assessment and enhancement for a hexapod machine

    Energy Technology Data Exchange (ETDEWEB)

    Mou, J.I. [Arizona State Univ., Tempe, AZ (United States); King, C. [Sandia National Labs., Livermore, CA (United States). Integrated Manufacturing Systems Center

    1998-03-19

    The focus of this study is to develop a sensor fused process modeling and control methodology to model, assess, and then enhance the performance of a hexapod machine for precision product realization. Deterministic modeling technique was used to derive models for machine performance assessment and enhancement. Sensor fusion methodology was adopted to identify the parameters of the derived models. Empirical models and computational algorithms were also derived and implemented to model, assess, and then enhance the machine performance. The developed sensor fusion algorithms can be implemented on a PC-based open architecture controller to receive information from various sensors, assess the status of the process, determine the proper action, and deliver the command to actuators for task execution. This will enhance a hexapod machine`s capability to produce workpieces within the imposed dimensional tolerances.

  12. 30 CFR 77.1801 - Overcurrent protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overcurrent protection. 77.1801 Section 77.1801... Wires and Trolley Feeder Wires § 77.1801 Overcurrent protection. Trolley wires and trolley feeder wires shall be provided with overcurrent protection. ...

  13. Superconducting rotating machines

    International Nuclear Information System (INIS)

    Smith, J.L. Jr.; Kirtley, J.L. Jr.; Thullen, P.

    1975-01-01

    The opportunities and limitations of the applications of superconductors in rotating electric machines are given. The relevant properties of superconductors and the fundamental requirements for rotating electric machines are discussed. The current state-of-the-art of superconducting machines is reviewed. Key problems, future developments and the long range potential of superconducting machines are assessed

  14. DEFORMATION WAVES AS A TRIGGER MECHANISM OF SEISMIC ACTIVITY IN SEISMIC ZONES OF THE CONTINENTAL LITHOSPHERE

    Directory of Open Access Journals (Sweden)

    S. I. Sherman

    2013-01-01

    Full Text Available Deformation waves as a trigger mechanism of seismic activity and migration of earthquake foci have been under discussion by researchers in seismology and geodynamics for over 50 years. Four sections of this article present available principal data on impacts of wave processes on seismicity and new data. The first section reviews analytical and experimental studies aimed at identification of relationships between wave processes in the lithosphere and seismic activity manifested as space-and-time migration of individual earthquake foci or clusters of earthquakes. It is concluded that with a systematic approach, instead of using a variety of terms to denote waves that trigger seismic process in the lithosphere, it is reasonable to apply the concise definition of ‘deformation waves’, which is most often used in fact.The second section contains a description of deformation waves considered as the trigger mechanism of seismic activity. It is concluded that a variety of methods are applied to identify deformation waves, and such methods are based on various research methods and concepts that naturally differ in sensitivity concerning detection of waves and/or impact of the waves on seismic process. Epicenters of strong earthquakes are grouped into specific linear or arc-shaped systems, which common criterion is the same time interval of the occurrence of events under analysis. On site the systems compose zones with similar time sequences, which correspond to the physical notion of moving waves (Fig. 9. Periods of manifestation of such waves are estimated as millions of years, and a direct consideration of the presence of waves and wave parameters is highly challenging. In the current state-of-the-art, geodynamics and seismology cannot provide any other solution yet.The third section presents a solution considering record of deformation waves in the lithosphere. With account of the fact that all the earthquakes with М≥3.0 are associated with

  15. Efficiency improvement of transport service by trolley buses based on the levels of their power demand

    Directory of Open Access Journals (Sweden)

    V. V. Aulin

    2014-12-01

    Full Text Available Purpose. Use efficiency improvement of trolley buses in passenger traffic based on power levels of electric energy input and terms adjustment of their maintenance. Methodology. In order to achieve this goal conformance of electric energy input by trolleybus to the transported amount of passengers taking into account characteristics of the route is offered to establish. The major indicators of the trolleybus operation are: speed of a race on lines, number of tractive motor firing, voltage and amperage in the network that were taken with accountants from a dashboard. Research results were tabulated and recorded with DVR. Along with the study of power consumption of electric energy input by a trolleybus passenger count was carried out too. Findings. The directly proportional dependence between the level of energy consumption by a trolleybus and the number of passengers for constant performance route was determined. Originality. As the criteria for evaluating the effectiveness of the trolleybus operation on the route is proposed to use the ratio between electricity consumption and number of passengers for these characteristics of the route. This is confirmed experimentally. The obtained formulas give the possibility to balance the force work and consequently the volume of energy consumption during the trolleybus movement on the rise and the descent. Practical value. The proposed criterion can be used to adjust the terms of maintenance on the individual program, that means individual maintenance (IM. Type of work performed at the IM should be determined on the basis of diagnostic data of the vehicle (V. The principles of IM were formulated: 1 the primary task is planned and preventative strategy to identify and eliminate troubleshooting and technical actions; 2 operational control of the vehicle (V technical condition on the basis of prediction of its state using the proposed criteria, that takes into account the dependence of power consumption to

  16. Automatic Processing and Interpretation of Long Records of Endogenous Micro-Seismicity: the Case of the Super-Sauze Soft-Rock Landslide.

    Science.gov (United States)

    Provost, F.; Malet, J. P.; Hibert, C.; Doubre, C.

    2017-12-01

    The Super-Sauze landslide is a clay-rich landslide located the Southern French Alps. The landslide exhibits a complex pattern of deformation: a large number of rockfalls are observed in the 100 m height main scarp while the deformation of the upper part of the accumulated material is mainly affected by material shearing along stable in-situ crests. Several fissures are locally observed. The shallowest layer of the accumulated material tends to behave in a brittle manner but may undergo fluidization and/or rapid acceleration. Previous studies have demonstrated the presence of a rich endogenous micro-seismicity associated to the deformation of the landslide. However, the lack of long-term seismic records and suitable processing chains prevented a full interpretation of the links between the external forcings, the deformation and the recorded seismic signals. Since 2013, two permanent seismic arrays are installed in the upper part of the landslide. We here present the methodology adopted to process this dataset. The processing chain consists of a set of automated methods for automatic and robust detection, classification and location of the recorded seismicity. Thousands of events are detected and further automatically classified. The classification method is based on the description of the signal through attributes (e.g. waveform, spectral content properties). These attributes are used as inputs to classify the signal using a Random Forest machine-learning algorithm in four classes: endogenous micro-quakes, rockfalls, regional earthquakes and natural/anthropogenic noises. The endogenous landslide sources (i.e. micro-quake and rockfall) are further located. The location method is adapted to the type of event. The micro-quakes are located with a 3D velocity model derived from a seismic tomography campaign and an optimization of the first arrival picking with the inter-trace correlation of the P-wave arrivals. The rockfalls are located by optimizing the inter

  17. Seismic induced earth pressures in buried vaults

    International Nuclear Information System (INIS)

    Miller, C.A.; Costantino, C.J.

    1994-01-01

    The magnitude and distribution of earth pressures acting on buried structures and induced by a seismic event are considered in this paper. A soil-structure-interaction analysis is performed for typical Department of Energy high level waste storage tanks using a lumped parameter model. The resulting soil pressure distributions are determined and compared with the static soil pressure to assess the design significance of the seismic induced soil pressures. It is found that seismic pressures do not control design unless the peak ground acceleration exceeds about 0.3 G. The effect of soil non linearities (resulting from local soil failure) are also found to have little effect on the predictions of the seismic response of the buried structure. The seismic induced pressures are found to be very similar to those predicted using the elastic model in ASCE 4-86

  18. Astor Pass Seismic Surveys Preliminary Report

    Energy Technology Data Exchange (ETDEWEB)

    Louie, John [UNR; Pullammanappallil, Satish [Optim; Faulds, James; Eisses, Amy; Kell, Annie; Frary, Roxanna; Kent, Graham

    2011-08-05

    In collaboration with the Pyramid Lake Paiute Tribe (PLPT), the University of Nevada, Reno (UNR) and Optim re-processed, or collected and processed, over 24 miles of 2d seismic-reflection data near the northwest corner of Pyramid Lake, Nevada. The network of 2d land surveys achieved a near-3d density at the Astor Pass geothermal prospect that the PLPT drilled during Nov. 2010 to Feb. 2011. The Bureau of Indian Affairs funded additional seismic work around the Lake, and an extensive, detailed single-channel marine survey producing more than 300 miles of section, imaging more than 120 ft below the Lake bottom. Optim’s land data collection utilized multiple heavy vibrators and recorded over 200 channels live, providing a state-of-the-art reflection-refraction data set. After advanced seismic analysis including first-arrival velocity optimization and prestack depth migration, the 2d sections show clear fault-plane reflections, in some areas as deep as 4000 ft, tying to distinct terminations of the mostly volcanic stratigraphy. Some lines achieved velocity control to 3000 ft depth; all lines show reflections and terminations to 5000 ft depth. Three separate sets of normal faults appear in an initial interpretation of fault reflections and stratigraphic terminations, after loading the data into the OpendTect 3d seismic visualization system. Each preliminary fault set includes a continuous trace more than 3000 ft long, and a swarm of short fault strands. The three preliminary normal-fault sets strike northerly with westward dip, northwesterly with northeast dip, and easterly with north dip. An intersection of all three fault systems documented in the seismic sections at the end of Phase I helped to locate the APS-2 and APS-3 slimholes. The seismic sections do not show the faults connected to the Astor Pass tufa spire, suggesting that we have imaged mostly Tertiary-aged faults. We hypothesize that the Recent, active faults that produced the tufa through hotspring

  19. Sustainable machining

    CERN Document Server

    2017-01-01

    This book provides an overview on current sustainable machining. Its chapters cover the concept in economic, social and environmental dimensions. It provides the reader with proper ways to handle several pollutants produced during the machining process. The book is useful on both undergraduate and postgraduate levels and it is of interest to all those working with manufacturing and machining technology.

  20. Salt Repository Project input to seismic design: Revision 0

    International Nuclear Information System (INIS)

    1987-12-01

    The Salt Repository Program (SRP) Input to Seismic Design (ISD) documents the assumptions, rationale, approaches, judgments, and analyses that support the development of seismic-specific data and information to be used for shaft design in accordance with the SRP Shaft Design Guide (SDG). The contents of this document are divided into four subject areas: (1) seismic assessment, (2) stratigraphy and material properties for seismic design, (3) development of seismic design parameters, and (4) host media stability. These four subject areas have been developed considering expected conditions at a proposed site in Deaf Smith County, Texas. The ISD should be used only in conjunction with seismic design of the exploratory and repository shafts. Seismic design considerations relating to surface facilities are not addressed in this document. 54 refs., 55 figs., 18 tabs

  1. Long seismic activity in the Porto dos Gaúchos Seismic Zone(PGSZ) - Amazon Craton Brazil

    Science.gov (United States)

    Barros, L. V.; Bowen, B. M. D.; Schmidt, K.

    2017-12-01

    The largest earthquake ever observed in the stable continental interior of the South American plate occurred in Serra do Tombador (ST), Mato Grosso state - Brazil, on January 31, 1955 with magnitude 6.2 m b . Since then no other earthquake has been located near the 1955 epicenter. However, in Porto dos Gaúchos (PG), 100 km northeast of ST, a recurrent seismicity has been observed since 1959. Both ST and PG are located in the Phanerozoic Parecis basin whose sediments overlies the crystalline basement of Amazon craton. Two magnitude 5 earthquakes occurred in PG, in 1998 and 2005 with intensities up to VI and V, respectively. These two main shocks were followed by aftershock sequences, studied by local seismic networks, last up today, almost 30 years later, period in which it was detected more than seven thousand of seismic events. Both sequences occurred in the same WSW-ENE oriented fault zone with right-lateral strike-slip mechanisms. The epicentral zone is near the northern border of Parecis basin, where there are buried grabens, generally trending WNW-ESE, such as the deep Mesoproterozoic Caiabis graben which lies partly beneath the Parecis basin. The seismogenic fault is located in a basement high, which is probably related with the same seismogenic feature responsible for the earthquakes in PGSZ. The 1955 earthquake, despite the uncertainty in its epicenter, does not seem to be directly related to any buried graben either. The seismicity in the PGSZ, therefore, is not directly related to rifted crust.Not considering the possibility of miss location in the ST earthquake, its isolated occurrence - from the perspective of new studies on intraplate seismicity - lead us to think that the PGSZ was activated by stresses released by the earthquake of 1955 and that the seismogenic fault of ST would have closed a cycle of activity. This would explain its seismic quiescence. However, other studies are necessary to prove this hypothesis, such as the measurement of the

  2. Use of seismic attributes for sediment classification

    Directory of Open Access Journals (Sweden)

    Fabio Radomille Santana

    2015-04-01

    Full Text Available A study to understand the relationships between seismic attributes extracted from 2D high-resolution seismic data and the seafloor's sediments of the surveyed area. As seismic attributes are features highly influenced by the medium through which the seismic waves are propagated, the authors can assume that it would be possible to characterise the geological nature of the seafloor by using these attributes. Herein, a survey was performed on the continental margin of the South Shetland Islands in Antarctica, where both 2D high-resolution seismic data and sediment gravity cores samples were simultaneously acquired. A computational script was written to extract the seismic attributes from the data, which have been statistically analysed with clustering analyses, such as principal components analysis, dendrograms and k-means classification. The extracted seismic attributes are the amplitude, the instantaneous phase, the instantaneous frequency, the envelope, the time derivative of the envelope, the second derivative of the envelope and the acceleration of phase. Statistical evaluation showed that geological classification of the seafloor's sediments is possible by associating these attributes according to their coherence. The methodologies here developed seem to be appropriate for glacio-marine environment and coarse-to-medium silt sediment found in the study area and may be applied to other regions in the same geological conditions.

  3. Fuel exchanging machine for a nuclear ship

    International Nuclear Information System (INIS)

    Hayashi, Tetsuji.

    1984-01-01

    Purpose: To prevent atmospheric contaminations upon fuel exchange thereby keep the environmental circumstance clean in the periphery of the nuclear ship. Constitution: A nuclear reactor container is disposed to the inside of a containing vessel in the ship body and a shutter is mounted to the upper opening of the ship body. Further, a landing container having a bottom opening equipped with shutter for alingning the upper opening equipped with shuuter of the ship is elevatably suspended to the trolley of a crane by way of a wire rope and a winch, and a fuel exchange cask is elevatably disposed to the inside of the landing container. Further, airs in the inside of the container is adapted to be discharged externally through a filter by means of a blower and the inside is kept at a negative pressure. Thus, since the containing vessel is covered with the landing container upon fuel exchanging operation, atmospheric contamination can be prevented sufficiently. (Sekiya, K.)

  4. Enhancement and feature extraction of RS images from seismic area and seismic disaster recognition technologies

    Science.gov (United States)

    Zhang, Jingfa; Qin, Qiming

    2003-09-01

    Many types of feature extracting of RS image are analyzed, and the work procedure of pattern recognizing in RS images of seismic disaster is proposed. The aerial RS image of Tangshan Great Earthquake is processed, and the digital features of various typical seismic disaster on the RS image is calculated.

  5. SHC, Seismic Hazard Assessment for Eastern US

    International Nuclear Information System (INIS)

    Savy, J.; Davis, B.

    2001-01-01

    1 - Description of program or function: SHC was developed as part of the Eastern United States (EUS) Seismic Hazard Characterization (SHC) Project to design an SHC methodology for the region east of the Rocky Mountains in a form suitable for probabilistic risk assessment and to apply that methodology to 69 site locations, some of them with local soil conditions. The method developed uses expert opinions to obtain the input to the analysis. SHC contains four modules which calculate the seismic hazard at a site located in a region of diffuse seismicity, where the seismicity is modeled by area sources. SHC integrates the opinions of 11 seismicity and five ground-motion experts. The PRDS model generates the discrete probability density function of the distances to the site for the various seismic source zones. These probability distributions are used by the COMAP module to generate the set of all alternative maps and the discrete probability density of the seismic zonation maps for each expert. The third module, ALEAS, uses these maps and their weights to calculate the best estimate and constant percentile hazard distribution resulting from the choice of a given seismicity expert for all ground-motion experts. This module can be used alone to perform a seismic hazard analysis as well as in conjunction with the other modules. The fourth module, COMB, combines the best- estimate and constant-percentile hazard over all seismicity experts, using the set of weights calculated by ALEAS, to produce the final probability distribution of the hazard for the site under consideration so that the hazard analysis can be performed for any location in the EUS. Local geological-site characteristics are incorporated in a generic fashion, and the data are developed in a generic manner. 2 - Method of solution: SHC uses a seismic-source approach utilizing statistical and geological evidence to define geographical regions with homogeneous Poisson activity throughout the zone, described by a

  6. Advanced Electrical Machines and Machine-Based Systems for Electric and Hybrid Vehicles

    Directory of Open Access Journals (Sweden)

    Ming Cheng

    2015-09-01

    Full Text Available The paper presents a number of advanced solutions on electric machines and machine-based systems for the powertrain of electric vehicles (EVs. Two types of systems are considered, namely the drive systems designated to the EV propulsion and the power split devices utilized in the popular series-parallel hybrid electric vehicle architecture. After reviewing the main requirements for the electric drive systems, the paper illustrates advanced electric machine topologies, including a stator permanent magnet (stator-PM motor, a hybrid-excitation motor, a flux memory motor and a redundant motor structure. Then, it illustrates advanced electric drive systems, such as the magnetic-geared in-wheel drive and the integrated starter generator (ISG. Finally, three machine-based implementations of the power split devices are expounded, built up around the dual-rotor PM machine, the dual-stator PM brushless machine and the magnetic-geared dual-rotor machine. As a conclusion, the development trends in the field of electric machines and machine-based systems for EVs are summarized.

  7. Asynchronized synchronous machines

    CERN Document Server

    Botvinnik, M M

    1964-01-01

    Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids” of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv

  8. Linearized inversion frameworks toward high-resolution seismic imaging

    KAUST Repository

    Aldawood, Ali

    2016-09-01

    Seismic exploration utilizes controlled sources, which emit seismic waves that propagate through the earth subsurface and get reflected off subsurface interfaces and scatterers. The reflected and scattered waves are recorded by recording stations installed along the earth surface or down boreholes. Seismic imaging is a powerful tool to map these reflected and scattered energy back to their subsurface scattering or reflection points. Seismic imaging is conventionally based on the single-scattering assumption, where only energy that bounces once off a subsurface scatterer and recorded by a receiver is projected back to its subsurface position. The internally multiply scattered seismic energy is considered as unwanted noise and is usually suppressed or removed from the recorded data. Conventional seismic imaging techniques yield subsurface images that suffer from low spatial resolution, migration artifacts, and acquisition fingerprint due to the limited acquisition aperture, number of sources and receivers, and bandwidth of the source wavelet. Hydrocarbon traps are becoming more challenging and considerable reserves are trapped in stratigraphic and pinch-out traps, which require highly resolved seismic images to delineate them. This thesis focuses on developing and implementing new advanced cost-effective seismic imaging techniques aiming at enhancing the resolution of the migrated images by exploiting the sparseness of the subsurface reflectivity distribution and utilizing the multiples that are usually neglected when imaging seismic data. I first formulate the seismic imaging problem as a Basis pursuit denoise problem, which I solve using an L1-minimization algorithm to obtain the sparsest migrated image corresponding to the recorded data. Imaging multiples may illuminate subsurface zones, which are not easily illuminated by conventional seismic imaging using primary reflections only. I then develop an L2-norm (i.e. least-squares) inversion technique to image

  9. Machine Shop Lathes.

    Science.gov (United States)

    Dunn, James

    This guide, the second in a series of five machine shop curriculum manuals, was designed for use in machine shop courses in Oklahoma. The purpose of the manual is to equip students with basic knowledge and skills that will enable them to enter the machine trade at the machine-operator level. The curriculum is designed so that it can be used in…

  10. Micromachined silicon seismic accelerometer development

    Energy Technology Data Exchange (ETDEWEB)

    Barron, C.C.; Fleming, J.G.; Montague, S. [and others

    1996-08-01

    Batch-fabricated silicon seismic transducers could revolutionize the discipline of seismic monitoring by providing inexpensive, easily deployable sensor arrays. Our ultimate goal is to fabricate seismic sensors with sensitivity and noise performance comparable to short-period seismometers in common use. We expect several phases of development will be required to accomplish that level of performance. Traditional silicon micromachining techniques are not ideally suited to the simultaneous fabrication of a large proof mass and soft suspension, such as one needs to achieve the extreme sensitivities required for seismic measurements. We have therefore developed a novel {open_quotes}mold{close_quotes} micromachining technology that promises to make larger proof masses (in the 1-10 mg range) possible. We have successfully integrated this micromolding capability with our surface-micromachining process, which enables the formation of soft suspension springs. Our calculations indicate that devices made in this new integrated technology will resolve down to at least sub-{mu}G signals, and may even approach the 10{sup -10} G/{radical}Hz acceleration levels found in the low-earth-noise model.

  11. Tools for educational access to seismic data

    Science.gov (United States)

    Taber, J. J.; Welti, R.; Bravo, T. K.; Hubenthal, M.; Frechette, K.

    2017-12-01

    Student engagement can be increased both by providing easy access to real data, and by addressing newsworthy events such as recent large earthquakes. IRIS EPO has a suite of access and visualization tools that can be used for such engagement, including a set of three tools that allow students to explore global seismicity, use seismic data to determine Earth structure, and view and analyze near-real-time ground motion data in the classroom. These tools are linked to online lessons that are designed for use in middle school through introductory undergraduate classes. The IRIS Earthquake Browser allows discovery of key aspects of plate tectonics, earthquake locations (in pseudo 3D) and seismicity rates and patterns. IEB quickly displays up to 20,000 seismic events over up to 30 years, making it one of the most responsive, practical ways to visualize historical seismicity in a browser. Maps are bookmarkable and preserve state, meaning IEB map links can be shared or worked into a lesson plan. The Global Seismogram Plotter automatically creates visually clear seismic record sections from selected large earthquakes that are tablet-friendly and can also to be printed for use in a classroom without computers. The plots are designed to be appropriate for use with no parameters to set, but users can also modify the plots, such as including a recording station near a chosen location. A guided exercise is provided where students use the record section to discover the diameter of Earth's outer core. Students can pick and compare phase arrival times onscreen which is key to performing the exercise. A companion station map shows station locations and further information and is linked to the record section. jAmaSeis displays seismic data in real-time from either a local instrument and/or from remote seismic stations that stream data using standard seismic data protocols, and can be used in the classroom or as a public display. Users can filter data, fit a seismogram to travel time

  12. Retrieval of reflections from seismic background?noise measurements

    NARCIS (Netherlands)

    Draganov, D.S.; Wapenaar, K.; Mulder, W.; Singer, J.; Verdel, A.

    2007-01-01

    The retrieval of the earth's reflection response from cross?correlations of seismic noise recordings can provide valuable information, which may otherwise not be available due to limited spatial distribution of seismic sources. We cross?correlated ten hours of seismic background?noise data acquired

  13. Patterned basal seismicity shows sub-ice stream bedforms

    Science.gov (United States)

    Barcheck, C. G.; Tulaczyk, S. M.; Schwartz, S. Y.

    2017-12-01

    Patterns in seismicity emanating from the bottom of fast-moving ice streams and glaciers may indicate localized patches of higher basal resistance— sometimes called 'sticky spots', or otherwise varying basal properties. These seismogenic basal areas resist an unknown portion of the total driving stress of the Whillans Ice Plain (WIP), in West Antarctica, but may play an important role in the WIP stick-slip cycle and ice stream slowdown. To better understand the mechanism and importance of basal seismicity beneath the WIP, we analyze seismic data collected by a small aperture (micro-earthquakes in Dec 2014, and we compare the resulting map of seismicity to ice bottom depth measured by airborne radar. The number of basal earthquakes per area within the network is spatially heterogeneous, but a pattern of two 400m wide streaks of high seismicity rates is evident, with >50-500 earthquakes detected per 50x50m grid cell in 2 weeks. These seismically active streaks are elongated approximately in the ice flow direction with a spacing of 750m. Independent airborne radar measurements of ice bottom depth from Jan 2013 show a low-amplitude ( 5m) undulation in the basal topography superposed on a regional gradient in ice bottom depth. The flow-perpendicular wavelength of these low-amplitude undulations is comparable to the spacing of the high seismicity bands, and the streaks of high seismicity intersect local lows in the undulating basal topography. We interpret these seismic and radar observations as showing seismically active sub-ice stream bedforms that are low amplitude and elongated in the direction of ice flow, comparable to the morphology of mega scale glacial lineations (MSGLs), with high basal seismicity rates observed in the MSGL troughs. These results have implications for understanding the formation mechanism of MSGLS and well as understanding the interplay between basal topographic roughness, spatially varying basal till and hydrologic properties, basal

  14. Seismic Probabilistic Risk Assessment (SPRA), approach and results

    International Nuclear Information System (INIS)

    Campbell, R.D.

    1995-01-01

    During the past 15 years there have been over 30 Seismic Probabilistic Risk Assessments (SPRAs) and Seismic Probabilistic Safety Assessments (SPSAs) conducted of Western Nuclear Power Plants, principally of US design. In this paper PRA and PSA are used interchangeably as the overall process is essentially the same. Some similar assessments have been done for reactors in Taiwan, Korea, Japan, Switzerland and Slovenia. These plants were also principally US supplied or built under US license. Since the restructuring of the governments in former Soviet Bloc countries, there has been grave concern regarding the safety of the reactors in these countries. To date there has been considerable activity in conducting partial seismic upgrades but the overall quantification of risk has not been pursued to the depth that it has in Western countries. This paper summarizes the methodology for Seismic PRA/PSA and compares results of two partially completed and two completed PRAs of soviet designed reactors to results from earlier PRAs on US Reactors. A WWER 440 and a WWER 1000 located in low seismic activity regions have completed PRAs and results show the seismic risk to be very low for both designs. For more active regions, partially completed PRAs of a WWER 440 and WWER 1000 located at the same site show the WWER 440 to have much greater seismic risk than the WWER 1000 plant. The seismic risk from the 1000 MW plant compares with the high end of seismic risk for earlier seismic PRAs in the US. Just as for most US plants, the seismic risk appears to be less than the risk from internal events if risk is measured is terms of mean core damage frequency. However, due to the lack of containment for the earlier WWER 440s, the risk to the public may be significantly greater due to the more probable scenario of an early release. The studies reported have not taken the accident sequences beyond the stage of core damage hence the public heath risk ratios are speculative. (author)

  15. Stress distribution and seismicity patterns of the 2011 seismic swarm in the Messinia basin, (South-Western Peloponnesus, Greece

    Directory of Open Access Journals (Sweden)

    G. Chouliaras

    2013-01-01

    Full Text Available In this investigation we examine the local stress field and the seismicity patterns associated with the 2011–2012 seismicity swarm in the Messinia basin, south-western Peloponnesus, Greece, using the seismological data of the National Observatory of Athens (NOA. During this swarm more than 2000 events were recorded in a 12 month period by the Hellenic Unified Seismological Network (HUSN and also by the additional local installation of four portable broadband seismographic stations by NOA.

    The results indicate a Gaussian distribution of swarm activity and the development of a seismicity cluster in a pre-existing seismic gap within the Messinia basin. Centroid Moment Tensor solutions demonstrate a normal fault trending northwest–southeast and dipping to the southwest primarily due to an extensional stress field. During this seismicity swarm an epicentre migration of the three largest shocks is observed, from one end of the rupture zone in the north-western part of the cluster, towards the other edge of the rupture in the south-eastern part of the cluster. This migration is found to follow the Coulomb failure criterion that predicts the advancement and retardation of the stress field and the patterns of increases and decreases of the seismicity rate (b-value of the frequency–magnitude relation.

  16. Simulating the seismic behaviour of soil slopes and embankments

    DEFF Research Database (Denmark)

    Zania, Varvara; Tsompanakis, Yiannis; Psarropoulos, Prodromos

    2010-01-01

    In the current study the clarification of the main assumptions, related to the two most commonly used methods of seismic slope stability analysis (pseudostatic and permanent deformation) is attempted. The seismic permanent displacements and the corresponding seismic coefficients were determined via...... parametric dynamic numerical analyses taking into account not only the main parameters dominating the seismic slope stability, but also the inherent assumptions of the applied approaches that affect the obtained results. The investigation conclude to a realistic procedure for seismic slope stability...

  17. The seismic monitoring network of Mt. Vesuvius

    Directory of Open Access Journals (Sweden)

    Massimo Orazi

    2013-11-01

    Full Text Available Mt. Vesuvius (southern Italy is one of the most hazardous volcanoes in the world. Its activity is currently characterized by moderate seismicity, with hypocenters located beneath the crater zone with depth rarely exceeding 5 km and magnitudes generally less than 3. The current configuration of the seismic monitoring network of Mt. Vesuvius consists of 18 seismic stations and 7 infrasound microphones. During the period 2006-2010 a seismic array with 48 channels was also operative. The station distribution provides appropriate coverage of the area around the volcanic edifice. The current development of the network and its geometry, under conditions of low seismic noise, allows locating seismic events with M<1. Remote instruments continuously transmit data to the main acquisition center in Naples. Data transmission is realized using different technological solutions based on UHF, Wi-Fi radio links, and TCP/IP client-server applications. Data are collected in the monitoring center of the Osservatorio Vesuviano (Italian National Institute of Geophysics and Volcanology, Naples section, which is equipped with systems for displaying and analyzing signals, using both real-time automatic and manual procedures. 24-hour surveillance allows to immediately communicate any significant anomaly to the Civil Protection authorities.

  18. Seismic safety of building structures of NPP Kozloduy III

    International Nuclear Information System (INIS)

    Varbanov, G.I.; Kostov, M.K.; Stefanov, D.D.; Kaneva, A.D.

    2005-01-01

    In the proposed paper is presented a general summary of the analyses carried out to evaluate the dynamic behavior and to assess the seismic safety of some safety related building structures of NPP Kozloduy. The design seismic loads for the site of Kozloduy NPP has been reevaluated and increased during and after the construction of investigated Units 5 and 6. Deterministic and probabilistic approaches are applied to assess the seismic vulnerability of the investigated structures, taking into account the newly defined seismic excitations. The presented results show sufficient seismic safety for the studied critical structures and good efficiency of the seismic upgrading. The applicability of the investigated structures at sites with some higher seismic activities is discussed. The presented study is dealing mainly with the civil structures of the Reactor building, Turbine hall, Diesel Generator Station and Water Intake Structure. (authors)

  19. Seismic activity parameters of the Finnish potential repository sites

    International Nuclear Information System (INIS)

    Saari, J.

    2000-10-01

    Posiva Oy has started a project for estimating the possible earthquake induced rock movements on the deposition holes containing canisters of spent nuclear fuel. These estimates will be made for the four investigation sites, Romuvaara, Kivetty, Olkiluoto and Haestholmen. This study deals with the current and future seismicity associated with the above mentioned sites. Seismic belts that participate the seismic behaviour of the studied sites have been identified and the magnitude-frequency distributions of these belts have been estimated. The seismic activity parameters of the sites have been deduced from the characteristics of the seismic belts in order to forecast the seismicity during the next 100,000 years. The report discusses the possible earthquakes induced by future glaciation. The seismic interpretation seems to indicate that the previous postglacial faults in Finnish Lapland have been generated in compressional environment. The orientation of the rather uniform compression has been NW-SE, which coincide with the current stress field. It seems that, although the impact of postglacial crustal rebound must have been significant, the impact of plate tectonics has been dominant. A major assumption of this study has been that future seismicity will generally resemble the current seismicity. However, when the postglacial seismicity is concerned, the magnitude-frequency distribution is likely different and the expected maximum magnitude will be higher. Maximum magnitudes of future postglacial earthquakes have been approximated by strain release examinations. Seismicity has been examined within the framework of the lineament maps, in order to associate the future significant earthquakes with active fault zones in the vicinity of the potential repository sites. (orig.)

  20. Operations plan for the Regional Seismic Test Network

    International Nuclear Information System (INIS)

    1981-01-01

    The Regional Seismic Test Network program was established to provide a capability for detection of extremely sensitive earth movements. Seismic signals from both natural and man-made earth motions will be analyzed with the ultimate objective of accurately locating underground nuclear explosions. The Sandia National Laboratories, Albuquerque, has designed an unattended seismic station capable of recording seismic information received at the location of the seismometers installed as part of that specific station. A network of stations is required to increase the capability of determining the source of the seismic signal and the location of the source. Current plans are to establish a five-station seismic network in the United States and Canada. The Department of Energy, Nevada Operations Office, has been assigned the responsibility for deploying, installing, and operating these remote stations. This Operation Plan provides the basic information and tasking to accomplish this assignment

  1. Nonlinear acoustic/seismic waves in earthquake processes

    International Nuclear Information System (INIS)

    Johnson, Paul A.

    2012-01-01

    Nonlinear dynamics induced by seismic sources and seismic waves are common in Earth. Observations range from seismic strong ground motion (the most damaging aspect of earthquakes), intense near-source effects, and distant nonlinear effects from the source that have important consequences. The distant effects include dynamic earthquake triggering—one of the most fascinating topics in seismology today—which may be elastically nonlinearly driven. Dynamic earthquake triggering is the phenomenon whereby seismic waves generated from one earthquake trigger slip events on a nearby or distant fault. Dynamic triggering may take place at distances thousands of kilometers from the triggering earthquake, and includes triggering of the entire spectrum of slip behaviors currently identified. These include triggered earthquakes and triggered slow, silent-slip during which little seismic energy is radiated. It appears that the elasticity of the fault gouge—the granular material located between the fault blocks—is key to the triggering phenomenon.

  2. Improvement of seismic observation systems in JOYO

    International Nuclear Information System (INIS)

    Sumino, Kozo; Suto, Masayoshi; Tanaka, Akihiro

    2013-01-01

    In the experimental fast reactor 'Joyo' in order to perform the seismic observation in and around the building block and ground, SMAC type seismographs had continuously been used for about 38 years. However, this equipment aged, and the 2011 off the Pacific Coast of Tohoku Earthquake on Mach 11, 2011 increased the importance of seismic data of the reactor facilities from the viewpoint of earthquake-proof safety. For these reasons, Joyo updated the system to the seismic observation system reflecting the latest technology/information, while keeping consistency with the observation data of the former seismographs (SMAC type seismograph). This updating improved various problems on the former observation seismographs. In addition, the installation of now observation points in the locations that are important in seismic safety evaluation expanded the data, and further improved the reliability of the seismic observation and evaluation on 'Joyo'. (A.O.)

  3. Hierarchical Bayesian Modeling of Fluid-Induced Seismicity

    Science.gov (United States)

    Broccardo, M.; Mignan, A.; Wiemer, S.; Stojadinovic, B.; Giardini, D.

    2017-11-01

    In this study, we present a Bayesian hierarchical framework to model fluid-induced seismicity. The framework is based on a nonhomogeneous Poisson process with a fluid-induced seismicity rate proportional to the rate of injected fluid. The fluid-induced seismicity rate model depends upon a set of physically meaningful parameters and has been validated for six fluid-induced case studies. In line with the vision of hierarchical Bayesian modeling, the rate parameters are considered as random variables. We develop both the Bayesian inference and updating rules, which are used to develop a probabilistic forecasting model. We tested the Basel 2006 fluid-induced seismic case study to prove that the hierarchical Bayesian model offers a suitable framework to coherently encode both epistemic uncertainty and aleatory variability. Moreover, it provides a robust and consistent short-term seismic forecasting model suitable for online risk quantification and mitigation.

  4. Seismic proof test of shielding block walls

    International Nuclear Information System (INIS)

    Ohte, Yukio; Watanabe, Takahide; Watanabe, Hiroyuki; Maruyama, Kazuhide

    1989-01-01

    Most of the shielding block walls used for building nuclear facilities are built by dry process. When a nuclear facility is designed, seismic waves specific at each site are set as input seismic motions and they are adopted in the design. Therefore, it is necessary to assure safety of the shielding block walls for earthquake by performing anti-seismic experiments under the conditions at each site. In order to establish the normal form that can be applied to various seismic conditions in various areas, Shimizu Corp. made an actual-size test samples for the shielding block wall and confirmed the safety for earthquake and validity of normalization. (author)

  5. Seismic stops for nuclear power plants

    International Nuclear Information System (INIS)

    Cloud, R.L.; Leung, J.S.M.; Anderson, P.H.

    1989-01-01

    In the regulated world of nuclear power, the need to have analytical proof of performance in hypothetical design-basis events such as earth quakes has placed a premium on design configurations that are mathematically tractable and easily analyzed. This is particularly true for the piping design. Depending on how the piping analyses are organized and on how old the plant is, there may be from 200 to 1000 separate piping runs to be designed, analyzed, and qualified. In this situation, the development of snubbers seemed like the answer to a piping engineer's prayer. At any place where seismic support was required but thermal motion had to be accommodated, a snubber could be specified. But, as experience has now shown, the program was solved only on paper. This article presents an alternative to conventional snubbers. These new devices, termed Seismic Stops are designed to replace snubbers directly and look like snubbers on the outside. But their design is based on a completely different principle. The original concept has adapted from early seismic-resistant pipe support designs used on fossil power plants in California. The fundamental idea is to provide a space envelope in which the pipe can expand freely between the hot and cold positions, but cannot move outside the envelope. Seismic Stops are designed to transmit any possible impact load, as would occur in an earthquake, away from the pipe itself to the Seismic Stop. The Seismic Stop pipe support is shown

  6. Seismic risks posed by mine flooding

    CSIR Research Space (South Africa)

    Goldbach, OD

    2009-09-01

    Full Text Available are allowed to flood. Such flooding-induced seismicity can have significant environmental, social and economic consequences, and may endanger neighbouring mines and surface communities. While fluid-induced seismicity has been observed in other settings (e...

  7. Existing reflection seismic data re-processing

    International Nuclear Information System (INIS)

    Higashinaka, Motonori; Sano, Yukiko; Kozawa, Takeshi

    2005-08-01

    This document is to report the results of existing seismic data re-processing around Horonobe town, Hokkaido, Japan, which is a part of the Horonobe Underground Research Project. The main purpose of this re-processing is to recognize the subsurface structure of Omagari Fault and fold system around Omagari Fault. The seismic lines for re-processing are TYHR-A3 line and SHRB-2 line, which JAPEX surveyed in 1975. Applying weathering static correction using refraction analysis and noise suppression procedure, we have much enhanced seismic profile. Following information was obtained from seismic re-processing results. TYHR-A3 line: There are strong reflections, dipping to the west. These reflections are corresponding western limb of anticline to the west side of Omagari Fault. SHRB-2 line: There are strong reflections, dipping to the west, at CDP 60-140, while there are reflections, dipping to the east, to the east side of CDP 140. These reflections correspond to the western limb and the eastern limb of the anticline, which is parallel to Omagari FAULT. This seismic re-processing provides some useful information to know the geological structure around Omagari Fault. (author)

  8. DRY TRANSFER FACILITY SEISMIC ANALYSIS

    International Nuclear Information System (INIS)

    EARNEST, S.; KO, H.; DOCKERY, W.; PERNISI, R.

    2004-01-01

    The purpose of this calculation is to perform a dynamic and static analysis on the Dry Transfer Facility, and to determine the response spectra seismic forces for the design basis ground motions. The resulting seismic forces and accelerations will be used in a subsequent calculation to complete preliminary design of the concrete shear walls, diaphragms, and basemat

  9. Seismic excitation by space shuttles

    Science.gov (United States)

    Kanamori, H.; Mori, J.; Sturtevant, B.; Anderson, D.L.; Heaton, T.

    1992-01-01

    Shock waves generated by the space shuttles Columbia (August 13, 1989), Atlantis (April 11, 1991) and Discovery (September 18, 1991) on their return to Edwards Air Force Base, California, were recorded by TERRAscope (Caltech's broadband seismic network), the Caltech-U.S.G.S Southern California Seismic Network (SCSN), and the University of Southern California (USC) Los Angeles Basin Seismic Network. The spatial pattern of the arrival times exhibits hyperbolic shock fronts from which the path, velocity and altitude of the space shuttle could be determined. The shock wave was acoustically coupled to the ground, converted to a seismic wave, and recorded clearly at the broadband TERRAscope stations. The acoustic coupling occurred very differently depending on the conditions of the Earth's surface surrounding the station. For a seismic station located on hard bedrock, the shock wave (N wave) was clearly recorded with little distortion. Aside from the N wave, very little acoustic coupling of the shock wave energy to the ground occurred at these sites. The observed N wave record was used to estimate the overpressure of the shock wave accurately; a pressure change of 0.5 to 2.2 mbars was obtained. For a seismic station located close to the ocean or soft sedimentary basins, a significant amount of shock wave energy was transferred to the ground through acoustic coupling of the shock wave and the oceanic Rayleigh wave. A distinct topography such as a mountain range was found effective to couple the shock wave energy to the ground. Shock wave energy was also coupled to the ground very effectively through large man made structures such as high rise buildings and offshore oil drilling platforms. For the space shuttle Columbia, in particular, a distinct pulse having a period of about 2 to 3 seconds was observed, 12.5 s before the shock wave, with a broadband seismograph in Pasadena. This pulse was probably excited by the high rise buildings in downtown Los Angeles which were

  10. Statistical Seismology and Induced Seismicity

    Science.gov (United States)

    Tiampo, K. F.; González, P. J.; Kazemian, J.

    2014-12-01

    While seismicity triggered or induced by natural resources production such as mining or water impoundment in large dams has long been recognized, the recent increase in the unconventional production of oil and gas has been linked to rapid rise in seismicity in many places, including central North America (Ellsworth et al., 2012; Ellsworth, 2013). Worldwide, induced events of M~5 have occurred and, although rare, have resulted in both damage and public concern (Horton, 2012; Keranen et al., 2013). In addition, over the past twenty years, the increase in both number and coverage of seismic stations has resulted in an unprecedented ability to precisely record the magnitude and location of large numbers of small magnitude events. The increase in the number and type of seismic sequences available for detailed study has revealed differences in their statistics that previously difficult to quantify. For example, seismic swarms that produce significant numbers of foreshocks as well as aftershocks have been observed in different tectonic settings, including California, Iceland, and the East Pacific Rise (McGuire et al., 2005; Shearer, 2012; Kazemian et al., 2014). Similarly, smaller events have been observed prior to larger induced events in several occurrences from energy production. The field of statistical seismology has long focused on the question of triggering and the mechanisms responsible (Stein et al., 1992; Hill et al., 1993; Steacy et al., 2005; Parsons, 2005; Main et al., 2006). For example, in most cases the associated stress perturbations are much smaller than the earthquake stress drop, suggesting an inherent sensitivity to relatively small stress changes (Nalbant et al., 2005). Induced seismicity provides the opportunity to investigate triggering and, in particular, the differences between long- and short-range triggering. Here we investigate the statistics of induced seismicity sequences from around the world, including central North America and Spain, and

  11. Seismic margin analysis technique for nuclear power plant structures

    International Nuclear Information System (INIS)

    Seo, Jeong Moon; Choi, In Kil

    2001-04-01

    In general, the Seismic Probabilistic Risk Assessment (SPRA) and the Seismic Margin Assessment(SAM) are used for the evaluation of realistic seismic capacity of nuclear power plant structures. Seismic PRA is a systematic process to evaluate the seismic safety of nuclear power plant. In our country, SPRA has been used to perform the probabilistic safety assessment for the earthquake event. SMA is a simple and cost effective manner to quantify the seismic margin of individual structural elements. This study was performed to improve the reliability of SMA results and to confirm the assessment procedure. To achieve this goal, review for the current status of the techniques and procedures was performed. Two methodologies, CDFM (Conservative Deterministic Failure Margin) sponsored by NRC and FA (Fragility Analysis) sponsored by EPRI, were developed for the seismic margin review of NPP structures. FA method was originally developed for Seismic PRA. CDFM approach is more amenable to use by experienced design engineers including utility staff design engineers. In this study, detailed review on the procedures of CDFM and FA methodology was performed

  12. Assessing the seismic risk potential of South America

    Science.gov (United States)

    Jaiswal, Kishor; Petersen, Mark D.; Harmsen, Stephen; Smoczyk, Gregory M.

    2016-01-01

    We present here a simplified approach to quantifying regional seismic risk. The seismic risk for a given region can be inferred in terms of average annual loss (AAL) that represents long-term value of earthquake losses in any one year caused from a long-term seismic hazard. The AAL are commonly measured in the form of earthquake shaking-induced deaths, direct economic impacts or indirect losses caused due to loss of functionality. In the context of South American subcontinent, the analysis makes use of readily available public data on seismicity, population exposure, and the hazard and vulnerability models for the region. The seismic hazard model was derived using available seismic catalogs, fault databases, and the hazard methodologies that are analogous to the U.S. Geological Survey’s national seismic hazard mapping process. The Prompt Assessment of Global Earthquakes for Response (PAGER) system’s direct empirical vulnerability functions in terms of fatality and economic impact were used for performing exposure and risk analyses. The broad findings presented and the risk maps produced herein are preliminary, yet they do offer important insights into the underlying zones of high and low seismic risks in the South American subcontinent. A more detailed analysis of risk may be warranted by engaging local experts, especially in some of the high risk zones identified through the present investigation.

  13. Criteria for the PNE seismic network

    International Nuclear Information System (INIS)

    Pruvost, N.L.

    1978-01-01

    A 1976 treaty between the United States and the Soviet Union permits a local seismic network to be deployed at the site of a peaceful nuclear explosion to monitor the event. Criteria for the design and selection of the data-acquisition equipment for such a network are provided. Constraints imposed by the protocol of the treaty, the environment, and the expected properties of seismic signals (based on experiences at the Nevada Test Site) are discussed. Conclusions are drawn about the desired operating mode. Criteria for a general seismic instrumentation system are described

  14. Seismic studies for nuclear installations sites

    International Nuclear Information System (INIS)

    Mohammadioun, B.; Faure, J.

    1988-01-01

    The french experience in seismic risks assessment for french nuclear installations permits to set out the objectives, the phases the geographic extensions of workings to be realized for the installation safety. The data to be collected for the safety analysis are specified, they concern the regional seismotectonics, the essential seismic data for determining the seism level to be taken into account and defining the soil movement spectra adapted to the site. It is necessary to follow up the seismic surveillance during the installation construction and life. 7 refs. (F.M.)

  15. Deep seismic sounding in northern Eurasia

    Science.gov (United States)

    Benz, H.M.; Unger, J.D.; Leith, W.S.; Mooney, W.D.; Solodilov, L.; Egorkin, A.V.; Ryaboy, V.Z.

    1992-01-01

    For nearly 40 years, the former Soviet Union has carried out an extensive program of seismic studies of the Earth's crust and upper mantle, known as “Deep Seismic Sounding” or DSS [Piwinskii, 1979; Zverev and Kosminskaya, 1980; Egorkin and Pavlenkova, 1981; Egorkin and Chernyshov, 1983; Scheimer and Borg, 1985]. Beginning in 1939–1940 with a series of small-scale seismic experiments near Moscow, DSS profiling has broadened into a national multiinstitutional exploration effort that has completed almost 150,000 km of profiles covering all major geological provinces of northern Eurasia [Ryaboy, 1989].

  16. Fast Estimation of Epicentral Distance and Magnitude from a Single Three Component Seismic Station Using Machine Learning Techniques

    Science.gov (United States)

    Ochoa Gutierrez, L. H.; Niño, L. F.; Vargas-Jimenez, C. A.

    2013-05-01

    To minimize adverse effects originated by high magnitude earthquakes, early warning has become a powerful tool to anticipate a seismic wave arrival to an specific location, bringing opportune information to people and government agencies to initiate a fast response. To do this, a very fast and accurate characterization of the event must be done but this process is often made using seismograms recorded in at least four stations where processing time is usually greater than the wave arrival time to the interest area, mainly in seismological coarse networks. A faster process can be done if only one three component seismic station, the closest unsaturated station with respect to the epicenter, is used. Here, we present a Support Vector Regression algorithm which calculates Magnitude and Epicentral Distance using only five seconds of signal since P wave onset. This algorithm was trained with 36 records of historical earthquakes, where the input included regression parameters of an exponential function estimated by least squares, of the waveform envelope and the maximum value of the observed waveform for each component in a single station. A ten-fold Cross Validation was applied for a Normalized Polynomial Kernel obtaining the mean absolute error for different exponents and complexity parameters. The Magnitude could be estimated with 0.16 units of mean absolute error and the distance with an error of 7.5 km for distances within 60 to 120 km. This kind of algorithm is easy to implement in hardware and can be used directly in the field seismological sensor to make the broadcast of estimations of these values possible to generate fast decisions at seismological control centers, increasing the possibility of having an effective reaction.

  17. Seismic refraction survey of the ANS preferred site

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.K. (Automated Sciences Group, Inc., Oak Ridge, TN (United States)); Hopkins, R.A. (Marrich, Inc., Knoxville, TN (United States)); Doll, W.E. (Oak Ridge National Lab., TN (United States))

    1992-02-01

    Between September 19, 1991 and October 8, 1991 personnel from Martin Marietta Energy Systems, Inc. (Energy Systems), Automated Sciences Group, Inc., and Marrich, Inc. performed a seismic refraction survey at the Advanced Neutron Source (ANS) preferred site. The purpose of this survey was to provide estimates of top-of-rock topography, based on seismic velocities, and to delineate variations in rock and soil velocities. Forty-four seismic refraction spreads were shot to determine top-of-rock depths at 42 locations. Nine of the seismic spreads were shot with long offsets to provide 216 top-of-rock depths for 4 seismic refraction profiles. The refraction spread locations were based on the grid for the ANS Phase I drilling program. Interpretation of the seismic refraction data supports the assumption that the top-of-rock surface generally follows the local topography. The shallow top-of-rock interface interpreted from the seismic refraction data is also supported by limited drill information at the site. Some zones of anomalous data are present that could be the result of locally variable weathering, a localized variation in shale content, or depth to top-of-rock greater than the site norm.

  18. Detecting aseismic strain transients from seismicity data

    Science.gov (United States)

    Llenos, A.L.; McGuire, J.J.

    2011-01-01

    Aseismic deformation transients such as fluid flow, magma migration, and slow slip can trigger changes in seismicity rate. We present a method that can detect these seismicity rate variations and utilize these anomalies to constrain the underlying variations in stressing rate. Because ordinary aftershock sequences often obscure changes in the background seismicity caused by aseismic processes, we combine the stochastic Epidemic Type Aftershock Sequence model that describes aftershock sequences well and the physically based rate- and state-dependent friction seismicity model into a single seismicity rate model that models both aftershock activity and changes in background seismicity rate. We implement this model into a data assimilation algorithm that inverts seismicity catalogs to estimate space-time variations in stressing rate. We evaluate the method using a synthetic catalog, and then apply it to a catalog of M???1.5 events that occurred in the Salton Trough from 1990 to 2009. We validate our stressing rate estimates by comparing them to estimates from a geodetically derived slip model for a large creep event on the Obsidian Buttes fault. The results demonstrate that our approach can identify large aseismic deformation transients in a multidecade long earthquake catalog and roughly constrain the absolute magnitude of the stressing rate transients. Our method can therefore provide a way to detect aseismic transients in regions where geodetic resolution in space or time is poor. Copyright 2011 by the American Geophysical Union.

  19. Machining of Machine Elements Made of Polymer Composite Materials

    Science.gov (United States)

    Baurova, N. I.; Makarov, K. A.

    2017-12-01

    The machining of the machine elements that are made of polymer composite materials (PCMs) or are repaired using them is considered. Turning, milling, and drilling are shown to be most widely used among all methods of cutting PCMs. Cutting conditions for the machining of PCMs are presented. The factors that most strongly affect the roughness parameters and the accuracy of cutting PCMs are considered.

  20. Boundary separating the seismically active reelfoot rift from the sparsely seismic Rough Creek graben, Kentucky and Illinois

    Science.gov (United States)

    Wheeler, R.L.

    1997-01-01

    The Reelfoot rift is the most active of six Iapetan rifts and grabens in central and eastern North America. In contrast, the Rough Creek graben is one of the least active, being seismically indistinguishable from the central craton of North America. Yet the rift and graben adjoin. Hazard assessment in the rift and graben would be aided by identification of a boundary between them. Changes in the strikes of single large faults, the location of a Cambrian transfer zone, and the geographic extent of alkaline igneous rocks provide three independent estimates of the location of a structural boundary between the rift and the graben. The boundary trends north-northwest through the northeastern part of the Fluorspar Area Fault Complex of Kentucky and Illinois, and has no obvious surface expression. The boundary involves the largest faults, which are the most likely to penetrate to hypocentral depths, and the boundary coincides with the geographic change from abundant seismicity in the rift to sparse seismicity in the graben. Because the structural boundary was defined by geologic variables that are expected to be causally associated with seismicity, it may continue to bound the Reelfoot rift seismicity in the future.

  1. Seismic qualification of civil engineering structures - Temelin NPP

    International Nuclear Information System (INIS)

    Schererova, K.; Holub, I.; Stepan, J.; Maly, J.

    2004-01-01

    Basic information is presented about the input data and methodology used for evaluation of Temelin NPP civil structures. The existing conditions as listed in POSAR report for the two reactor units are considered. The original design of the power plant assumed a lower level of locality seismic hazard, as followed from seismological surveys that where then available. Later the seismic assessment was updated while fully respecting IAEA recommendations and using a minimum value of acceleration in the horizontal direction PGAHOR = 0.1 g at free field level for SL-2. In relation to the new seismic project, new qualification of the structures, components and systems classed as seismic resistance category 1 was carried out. Since the Czech Republic has no specific technical standards for seismic resistance evaluation of nuclear power plants, a detailed methodology was elaborated, comprising principles of seismic resistance evaluation based on IAEA guides and on common practice in countries with advanced nuclear power engineering. (P.A.)

  2. Use of experience data for DOE seismic evaluations

    International Nuclear Information System (INIS)

    Barlow, M.W.; Budnitz, R.; Eder, S.J.; Eli, M.W.

    1993-01-01

    As dictated by DOE Order 5480.28, seismic evaluations of essential systems and components at DOE facilities will be conducted over the next several years. For many of these systems and components, few, if any, seismic requirements applied to the original design, procurement, installation, and maintenance process. Thus the verification of the seismic adequacy of existing systems and components presents a difficult challenge. DOE has undertaken development of the criteria and procedures for these seismic evaluations that will maximize safety benefits in a timely and cost effective manner. As demonstrated in previous applications at DOE facilities and by the experience from the commercial nuclear power industry, use of experience data for these evaluations is the only viable option for most existing systems and components. This paper describes seismic experience data, the needs at DOE facilities, the precedent of application at nuclear power plants and DOE facilities, and the program being put in place for the seismic verification task ahead for DOE

  3. Erosion influences the seismicity of active thrust faults.

    Science.gov (United States)

    Steer, Philippe; Simoes, Martine; Cattin, Rodolphe; Shyu, J Bruce H

    2014-11-21

    Assessing seismic hazards remains one of the most challenging scientific issues in Earth sciences. Deep tectonic processes are classically considered as the only persistent mechanism driving the stress loading of active faults over a seismic cycle. Here we show via a mechanical model that erosion also significantly influences the stress loading of thrust faults at the timescale of a seismic cycle. Indeed, erosion rates of about ~0.1-20 mm yr(-1), as documented in Taiwan and in other active compressional orogens, can raise the Coulomb stress by ~0.1-10 bar on the nearby thrust faults over the inter-seismic phase. Mass transfers induced by surface processes in general, during continuous or short-lived and intense events, represent a prominent mechanism for inter-seismic stress loading of faults near the surface. Such stresses are probably sufficient to trigger shallow seismicity or promote the rupture of deep continental earthquakes up to the surface.

  4. Overview on seismic evaluation and retrofitting within JICA Technical Cooperation Project on reduction of seismic risk in Romania

    International Nuclear Information System (INIS)

    Seki, M.; Vacareanu, R.; Pavel, M.; Lozinca, E.; Cotofana, D.; Chesca, B.; Georgescu, B.; Kaminosono, T.

    2007-01-01

    The objective of this paper is to give an overview on the seismic evaluation and retrofitting procedures of reinforced concrete buildings within JICA technical cooperation project in Romania. The content of the paper covers a) an outline of the seismic evaluation; history and comparison of Romanian seismic design codes with the Japanese seismic evaluation guidelines, b) an outline of the retrofitting techniques which were transferred from Japan to Romania and structural tests for retrofitting techniques employed in Romania and c) retrofitting details that were used by JICA/NCSRR in the retrofitting design of two vulnerable buildings in Bucharest. The above-mentioned retrofitting projects are now under development of detailed design and therefore, in the near future, refining and improvement of solutions will be performed. (authors)

  5. Seismic ground motion modelling and damage earthquake scenarios: A bridge between seismologists and seismic engineers

    International Nuclear Information System (INIS)

    Panza, G.F.; Romanelli, F.; Vaccari. F.; . E-mails: Luis.Decanini@uniroma1.it; Fabrizio.Mollaioli@uniroma1.it)

    2002-07-01

    The input for the seismic risk analysis can be expressed with a description of 'roundshaking scenarios', or with probabilistic maps of perhaps relevant parameters. The probabilistic approach, unavoidably based upon rough assumptions and models (e.g. recurrence and attenuation laws), can be misleading, as it cannot take into account, with satisfactory accuracy, some of the most important aspects like rupture process, directivity and site effects. This is evidenced by the comparison of recent recordings with the values predicted by the probabilistic methods. We prefer a scenario-based, deterministic approach in view of the limited seismological data, of the local irregularity of the occurrence of strong earthquakes, and of the multiscale seismicity model, that is capable to reconcile two apparently conflicting ideas: the Characteristic Earthquake concept and the Self Organized Criticality paradigm. Where the numerical modeling is successfully compared with records, the synthetic seismograms permit the microzoning, based upon a set of possible scenario earthquakes. Where no recordings are available the synthetic signals can be used to estimate the ground motion without having to wait for a strong earthquake to occur (pre-disaster microzonation). In both cases the use of modeling is necessary since the so-called local site effects can be strongly dependent upon the properties of the seismic source and can be properly defined only by means of envelopes. The joint use of reliable synthetic signals and observations permits the computation of advanced hazard indicators (e.g. damaging potential) that take into account local soil properties. The envelope of synthetic elastic energy spectra reproduces the distribution of the energy demand in the most relevant frequency range for seismic engineering. The synthetic accelerograms can be fruitfully used for design and strengthening of structures, also when innovative techniques, like seismic isolation, are employed. For these

  6. Second and Third Quarters Hanford Seismic Report for Fiscal Year 1999

    Energy Technology Data Exchange (ETDEWEB)

    Hartshorn, Donald C.; Reidel, Stephen P.; Rohay, Alan C.

    1999-10-08

    Hanford Seismic Monitoring provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network (HSN) for the U.S. Department of Energy and its contractors. Hanford Seismic Monitoring also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site.

  7. Quasi-seismic scaling processes in sea ice

    International Nuclear Information System (INIS)

    Chmel, A; Smirnov, V N

    2011-01-01

    The cracking, shearing and stick–slip motions in sea ice are similar to those in fracturing geostructures. In this work, the fracture-related, quasi-seismic activity in the Arctic ice pack was monitored during a large-scale ice cover fragmentation that occurred in March 2008. This fragmentation resulted in the formation of a two-dimensional 'fault' clearly seen in satellite images. The energy distribution in elastic waves detected by seismic tiltmeters follows the power law in pre- and post-faulting periods. The power exponent decreases as the 'catastrophe' approaches, and exhibits a trend to restore its initial value after the large-scale perturbation. The detected fracture events are correlated in time in the sense of a scaling relation. A quiescent period (very low quasi-seismic activity) was observed before 'faulting'. A close similarity in scaling characteristics between the crustal seismicity and quasi-seismic activity observed in the ice pack is discussed from the viewpoint of the role of heterogeneity in the behavior of large-scale critical systems

  8. Seismic response of uplifting concrete gravity dams

    International Nuclear Information System (INIS)

    Leger, P.; Sauve, G.; Bhattacharjee, S.

    1992-01-01

    The foundation interaction effects on the seismic response of dam-foundation systems have generally been studied using the linear elastic finite element models. In reality, the foundation can not develop effective tensile stresses to a significant degree along the interface. A two-dimensional finite element model, in which nonlinear gap elements are used at the dam-foundation interface to determine the uplift response of concrete gravity dams subjected to seismic loads, is presented. Time domain analyses were performed for a wide range of modelling assumptions such as dam height, interface uplift pressure, interface mesh density, and earthquake input motions, that were systematically varied to find their influence on the seismic response. The nonlinear interface behavior generally reduces the seismic response of dam-foundation systems acting as a seismic isolation mechanism, and may increase the safety against sliding by reducing the base shear transmitted to the foundation. 4 refs., 5 figs., 6 tabs

  9. Seismic Energy Generation and Partitioning into Various Regional Phases from Different Seismic Sources in the Middle East Region

    Science.gov (United States)

    2007-09-20

    a), a 3C SP seismic station (b) and a sensor BlastMateIII, Oron quarry (c)............................... 9 Figure 7. Seismic Array MMAI (AS49) of... seismic stations of Jordan network at distance range 22-285 km (a), and at IMS array MMAI (AS49) at 350 km, BP filtered 2-8 Hz (b...sites and portable stations, inserts show detailed location of the tripartite array elements (st.6) and configuration of the explosion boreholes and

  10. The Banat seismic network: Evolution and performance

    International Nuclear Information System (INIS)

    Oros, E.

    2002-01-01

    In the Banat Seismic Region, with its important seismogenic zones (Banat and Danube), operates today the Banat Seismic Network. This network has four short period seismic stations telemetered at the Timisoara Seismological Observatory (since 1995): Siria, Banloc, Buzias and Timisoara. The stations are equipped with short-period S13 seismometers (1 second). The data recorded by the short-period stations are telemetered to Timisoara where they are digitized at 50 samples per second, with 16 bit resolution. At Timisoara works SAPS, an automated system for data acquisition and processing, which performs real-time event detection (based on Allen algorithm), discrimination between local and teleseismic events, automatic P and S waves picking, location and magnitude determination for local events and teleseisms, 'feeding' of an Automatic Data Request Manager with phases, locations and waveforms, sending of earthquake information (as phases and location), by e-mail to Bucharest. The beginning of the seismological observations in Banat is in the 1880's (Timisoara Meteorological Observatory). The first seismograph was installed in Timisoara in 1901, and its systematic observations began in 1902. The World War I interrupted its work. In 1942 Prof. I. Curea founded the Seismic Station Timisoara, and since 1967 until today this station worked into a special building. After 1972 two stations with high amplification were installed in Retezat Mts (Gura Zlata) and on Nera Valey (Susara), as a consequence of the research results. Since 1982 Buzias station began to work completing the Banat Seismic Network. Therefore, the network could detect and locate any local seismic event with M > 2.2. Moreover, up to 20 km distance from each station any seismic event could be detected over M = 0.5. The paper also presents the quality of the locations versus different local seismic sources. (author)

  11. Maturity of nearby faults influences seismic hazard from hydraulic fracturing

    Science.gov (United States)

    Kozłowska, Maria; Brudzinski, Michael R.; Friberg, Paul; Skoumal, Robert J.; Baxter, Nicholas D.; Currie, Brian S.

    2018-02-01

    Understanding the causes of human-induced earthquakes is paramount to reducing societal risk. We investigated five cases of seismicity associated with hydraulic fracturing (HF) in Ohio since 2013 that, because of their isolation from other injection activities, provide an ideal setting for studying the relations between high-pressure injection and earthquakes. Our analysis revealed two distinct groups: (i) deeper earthquakes in the Precambrian basement, with larger magnitudes (M > 2), b-values 1.5, and few post–shut-in earthquakes. Based on geologic history, laboratory experiments, and fault modeling, we interpret the deep seismicity as slip on more mature faults in older crystalline rocks and the shallow seismicity as slip on immature faults in younger sedimentary rocks. This suggests that HF inducing deeper seismicity may pose higher seismic hazards. Wells inducing deeper seismicity produced more water than wells with shallow seismicity, indicating more extensive hydrologic connections outside the target formation, consistent with pore pressure diffusion influencing seismicity. However, for both groups, the 2 to 3 h between onset of HF and seismicity is too short for typical fluid pressure diffusion rates across distances of ˜1 km and argues for poroelastic stress transfer also having a primary influence on seismicity.

  12. Maturity of nearby faults influences seismic hazard from hydraulic fracturing.

    Science.gov (United States)

    Kozłowska, Maria; Brudzinski, Michael R; Friberg, Paul; Skoumal, Robert J; Baxter, Nicholas D; Currie, Brian S

    2018-02-20

    Understanding the causes of human-induced earthquakes is paramount to reducing societal risk. We investigated five cases of seismicity associated with hydraulic fracturing (HF) in Ohio since 2013 that, because of their isolation from other injection activities, provide an ideal setting for studying the relations between high-pressure injection and earthquakes. Our analysis revealed two distinct groups: ( i ) deeper earthquakes in the Precambrian basement, with larger magnitudes (M > 2), b-values 1.5, and few post-shut-in earthquakes. Based on geologic history, laboratory experiments, and fault modeling, we interpret the deep seismicity as slip on more mature faults in older crystalline rocks and the shallow seismicity as slip on immature faults in younger sedimentary rocks. This suggests that HF inducing deeper seismicity may pose higher seismic hazards. Wells inducing deeper seismicity produced more water than wells with shallow seismicity, indicating more extensive hydrologic connections outside the target formation, consistent with pore pressure diffusion influencing seismicity. However, for both groups, the 2 to 3 h between onset of HF and seismicity is too short for typical fluid pressure diffusion rates across distances of ∼1 km and argues for poroelastic stress transfer also having a primary influence on seismicity.

  13. Seismic isolation of buildings using composite foundations based on metamaterials

    Science.gov (United States)

    Casablanca, O.; Ventura, G.; Garescı, F.; Azzerboni, B.; Chiaia, B.; Chiappini, M.; Finocchio, G.

    2018-05-01

    Metamaterials can be engineered to interact with waves in entirely new ways, finding application on the nanoscale in various fields such as optics and acoustics. In addition, acoustic metamaterials can be used in large-scale experiments for filtering and manipulating seismic waves (seismic metamaterials). Here, we propose seismic isolation based on a device that combines some properties of seismic metamaterials (e.g., periodic mass-in-mass systems) with that of a standard foundation positioned right below the building for isolation purposes. The concepts on which this solution is based are the local resonance and a dual-stiffness structure that preserves large (small) rigidity for compression (shear) effects. In other words, this paper introduces a different approach to seismic isolation by using certain principles of seismic metamaterials. The experimental demonstrator tested on the laboratory scale exhibits a spectral bandgap that begins at 4.5 Hz. Within the bandgap, it filters more than 50% of the seismic energy via an internal dissipation process. Our results open a path toward the seismic resilience of buildings and a critical infrastructure to shear seismic waves, achieving higher efficiency compared to traditional seismic insulators and passive energy-dissipation systems.

  14. Probabilistic seismic hazard assessment of NW and central ...

    Indian Academy of Sciences (India)

    The Himalayan region has undergone significant development and to ensure safe and secure progress in such a seismically vulnerable region there is a need for hazard assessment. For seismic hazard assessment, it is important to assess the quality, consistency, and homogeneity of the seismicity data collected from ...

  15. Improving Machining Accuracy of CNC Machines with Innovative Design Methods

    Science.gov (United States)

    Yemelyanov, N. V.; Yemelyanova, I. V.; Zubenko, V. L.

    2018-03-01

    The article considers achieving the machining accuracy of CNC machines by applying innovative methods in modelling and design of machining systems, drives and machine processes. The topological method of analysis involves visualizing the system as matrices of block graphs with a varying degree of detail between the upper and lower hierarchy levels. This approach combines the advantages of graph theory and the efficiency of decomposition methods, it also has visual clarity, which is inherent in both topological models and structural matrices, as well as the resiliency of linear algebra as part of the matrix-based research. The focus of the study is on the design of automated machine workstations, systems, machines and units, which can be broken into interrelated parts and presented as algebraic, topological and set-theoretical models. Every model can be transformed into a model of another type, and, as a result, can be interpreted as a system of linear and non-linear equations which solutions determine the system parameters. This paper analyses the dynamic parameters of the 1716PF4 machine at the stages of design and exploitation. Having researched the impact of the system dynamics on the component quality, the authors have developed a range of practical recommendations which have enabled one to reduce considerably the amplitude of relative motion, exclude some resonance zones within the spindle speed range of 0...6000 min-1 and improve machining accuracy.

  16. Machinability of nickel based alloys using electrical discharge machining process

    Science.gov (United States)

    Khan, M. Adam; Gokul, A. K.; Bharani Dharan, M. P.; Jeevakarthikeyan, R. V. S.; Uthayakumar, M.; Thirumalai Kumaran, S.; Duraiselvam, M.

    2018-04-01

    The high temperature materials such as nickel based alloys and austenitic steel are frequently used for manufacturing critical aero engine turbine components. Literature on conventional and unconventional machining of steel materials is abundant over the past three decades. However the machining studies on superalloy is still a challenging task due to its inherent property and quality. Thus this material is difficult to be cut in conventional processes. Study on unconventional machining process for nickel alloys is focused in this proposed research. Inconel718 and Monel 400 are the two different candidate materials used for electrical discharge machining (EDM) process. Investigation is to prepare a blind hole using copper electrode of 6mm diameter. Electrical parameters are varied to produce plasma spark for diffusion process and machining time is made constant to calculate the experimental results of both the material. Influence of process parameters on tool wear mechanism and material removal are considered from the proposed experimental design. While machining the tool has prone to discharge more materials due to production of high energy plasma spark and eddy current effect. The surface morphology of the machined surface were observed with high resolution FE SEM. Fused electrode found to be a spherical structure over the machined surface as clumps. Surface roughness were also measured with surface profile using profilometer. It is confirmed that there is no deviation and precise roundness of drilling is maintained.

  17. First results of cross-correlation analysis of ambient seismic noise from the Hellenic Unified Seismic Network

    NARCIS (Netherlands)

    Panou, Areti; Paulssen, Hanneke; Hatzidimitriou, Panagiotis

    2015-01-01

    In this study we present phase velocity maps that were obtained from the cross-correlation analysis of ambient seismic noise recorded in the region of Greece.We used one year (2013) of ambient seismic data obtained from the vertical component of 64 broadband permanent seismological stations that are

  18. [The set of wearable medical equipment for medical and nursing teams].

    Science.gov (United States)

    Efimenko, N a; Valevskii, V V; Lyutov, V V; Makhnovskii, A I; Sorokin, S I; Blinda, I V

    2015-06-01

    The kit is designed in accordance with the list of the first medical aid procedures and syndromic standards of emergency medical care providing. The kit contains modern local hemostatic agents, vent tubes, cricothyrotomy, needles to eliminate pneumothorax, portable oxygen machine, sets for intravenous and intraosseous infusion therapy, collapsible plastic tires, anti-shock pelvic girdle, and other medical products and pharmaceuticals. As containers used backpack and trolley bag on wheels camouflage colours. For the convenience and safety of the personnel of the vest is designed discharge to be converted in the body armour.

  19. Design of hoisting device used in nuclear power plants. KTA safety engineering code. Draft amendment, as of 6/98

    International Nuclear Information System (INIS)

    1998-06-01

    The draft amendment specifies, according to the hazards involved, (a) the general provisions, (b) additional provisions supplementing the general provisions, (c) more stringent provisions relating to aggravated risks, applicable to lifting gear, and (d) additional requirements for elevators in reactor containments and refuelling equipment, to be taken into account in the design of hoisting device used in nuclear power plants. The term hoisting device in this context covers elevators, cranes, winches, trolleys, load carrying equipment, and LWR refuelling machines as are used in nuclear power plants. (orig./CB) [de

  20. The achievements of the Z-machine; Les exploits de la Z-machine

    Energy Technology Data Exchange (ETDEWEB)

    Larousserie, D

    2008-03-15

    The ZR-machine that represents the latest generation of Z-pinch machines has recently begun preliminary testing before its full commissioning in Albuquerque (Usa). During its test the machine has well operated with electrical currents whose intensities of 26 million Ampere are already 2 times as high as the intensity of the operating current of the previous Z-machine. In 2006 the Z-machine reached temperatures of 2 billions Kelvin while 100 million Kelvin would be sufficient to ignite thermonuclear fusion. In fact the concept of Z-pinch machines was imagined in the fifties but the technological breakthrough that has allowed this recent success and the reborn of Z-machine, was the replacement of gas by an array of metal wires through which the electrical current flows and vaporizes it creating an imploding plasma. It is not well understood why Z-pinch machines generate far more radiation than theoretically expected. (A.C.)