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Sample records for operation experience operation

  1. Operating experience

    McRae, L.P.; Six, D.E.

    1991-01-01

    In 1987, Westinghouse Hanford Company began operating a first-generation integrated safeguards system in the Plutonium Finishing Plant storage vaults. This Vault Safety and Inventory System is designed to integrate data into a computer-based nuclear material inventory monitoring system. The system gathers, in real time, measured physical parameters that generate nuclear material inventory status data for thousands of stored items and sends tailored report to the appropriate users. These data include canister temperature an bulge data reported to Plant Operations and Material Control and Accountability personnel, item presence and identification data reported to Material Control and Accountability personnel, and unauthorized item movement data reported to Security response forces and Material Control and Accountability personnel. The Westinghouse Hanford Company's experience and operational benefits in using this system for reduce radiation exposure, increase protection against insider threat, and real-time inventory control are discussed in this paper

  2. CANDU operating experience

    McConnell, L.G.; Woodhead, L.W.; Fanjoy, G.R.; Thurygill, E.W.

    1980-05-01

    The CANDU-PHW program is based upon 38 years of heavy water reactor experience with 35 years of operating experience. Canada has had 72 reactor years of nuclear-electric operations experience with 10 nuclear units in 4 generating stations during a period of 18 years. All objectives have been met with outstanding performance: worker safety, public safety, environmental emissions, reliable electricity production, and low electricity cost. The achievement has been realized through total teamwork involving all scientific disciplines and all project functions (research, design, manufacturing, construction, and operation). (auth)

  3. CANDU operating experience

    McConnell, L.G.; Woodhead, L.W.; Fanjoy, G.R.

    1982-03-01

    The CANDU Pressurized Heavy Water (CANDU-PHW) type of nuclear electric generating station has been developed jointly by Atomic Energy of Canada Limited and Ontario Hydro. This paper highlights Ontario Hydro's operating experience using the CANDU-PHW system, with a focus on the operating performance and costs, reliability of system components and nuclear safety considerations both to the workers and the public

  4. Operating experience feedback

    Cimesa, S.

    2007-01-01

    Slovenian Nuclear Safety Administration (SNSA) has developed its own system for tracking, screening and evaluating the operating experiences of the nuclear installations. The SNSA staff regularly tracks the operating experiences throughout the world and screens them on the bases of applicability for the Slovenian nuclear facilities. The operating experiences, which pass the screening, are thoroughly evaluated and also recent operational events in these facilities are taken into account. If needed, more information is gathered to evaluate the conditions of the Slovenian facilities and appropriate corrective actions are considered. The result might be the identification of the need for modification at the licensee, the need for modification of internal procedures in the SNSA or even the proposal for the modification of regulations. Information system helps everybody to track the process of evaluation and proper logging of activities. (author)

  5. Operating experience with snubbers

    Levin, H.; Cudlin, R.

    1978-06-01

    Recent operating experience with hydraulic and mechanical snubbers has indicated that there is a need to evaluate current practice in the industry associated with snubber qualification testing programs, design and analysis procedures, selection and specification criteria, and the preservice inspection and inservice surveillance programs. The report provides a summary of operational experiences that represent problems that are generic throughout the industry. Generic Task A-13 is part of the NRC Program for the Resolution of Generic Issues Related to Nuclear Power Plants described in NUREG-0410. The report is based upon a rather large amount of data that have become available in the past four years. These data have been evaluated by the Division of Operating Reactors to develop a data base for use in connection with several NRC activities including Category A, Technical Activity A-13 (Snubbers); the Standard Review Plan; future Regulatory Guides; ASME Code Provisions; and various technical specifications of operating nuclear power plants

  6. Operating experience: safety perspective

    Piplani, Vivek; Krishnamurthy, P.R.; Kumar, Neeraj; Upadhyay, Devendra

    2015-01-01

    Operating Experience (OE) provides valuable information for improving NPP safety. This may include events, precursors, deviations, deficiencies, problems, new insights to safety, good practices, lessons and corrective actions. As per INSAG-10, an OE program caters as a fundamental means for enhancing the defence-in-depth at NPPs and hence should be viewed as ‘Continuous Safety Performance Improvement Tool’. The ‘Convention on Nuclear Safety’ also recognizes the OE as a tool of high importance for enhancing the NPP safety and its Article 19 mandates each contracting party to establish an effective OE program at operating NPPs. The lessons drawn from major accidents at Three Mile Island, Chernobyl and Fukushima Daiichi NPPs had prompted nuclear stalwarts to change their safety perspective towards NPPs and to frame sound policies on issues like safety culture, severe accident prevention and mitigation. An effective OE program, besides correcting current/potential problems, help in proactively improving the NPP design, operating and maintenance procedures, practices, training, etc., and thus plays vital role in ensuring safe and efficient operation of NPPs. Further it enhances knowledge with regard to equipment operating characteristics, system performance trends and provides data for quantitative and qualitative safety analysis. Besides all above, an OE program inculcates a learning culture in the organisation and thus helps in continuously enhancing the expertise, technical competency and knowledge base of its staff. Nuclear and Radiation Facilities in India are regulated by Atomic Energy Regulatory Board (AERB). Operating Plants Safety Division (OPSD) of AERB is involved in managing operating experience activities. This paper provides insights about the operating experience program of OPSD, AERB (including its on-line data base namely OPSD STAR) and its utilisation in improving the regulations and safety at Indian NPPs/projects. (author)

  7. ATLAS IBL operational experience

    AUTHOR|(INSPIRE)INSPIRE-00237659; The ATLAS collaboration

    2017-01-01

    The Insertable B-Layer (IBL) is the inner most pixel layer in the ATLAS experiment, which was installed at 3.3 cm radius from the beam axis in 2014 to improve the tracking performance. To cope with the high radiation and hit occupancy due to proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed for the IBL. After the long shut-down period over 2013 and 2014, the ATLAS experiment started data-taking in May 2015 for Run-2 of the Large Hadron Collider (LHC). The IBL has been operated successfully since the beginning of Run-2 and shows excellent performance with the low dead module fraction, high data-taking efficiency and improved tracking capability. The experience and challenges in the operation of the IBL is described as well as its performance.

  8. GNF2 Operating Experience

    Schardt, John

    2007-01-01

    GNF's latest generation fuel product, GNF2, is designed to deliver improved nuclear efficiency, higher bundle and cycle energy capability, and more operational flexibility. But along with high performance, our customers face a growing need for absolute fuel reliability. This is driven by a general sense in the industry that LWR fuel reliability has plateaued. Too many plants are operating with fuel leakers, and the impact on plant operations and operator focus is unacceptable. The industry has responded by implementing an INPO-coordinated program aimed at achieving leaker-free reliability by 2010. One focus area of the program is the relationship between fuel performance (i.e., duty) and reliability. The industry recognizes that the right balance between performance and problem-free fuel reliability is critical. In the development of GNF2, GNF understood the requirement for a balanced solution and utilized a product development and introduction strategy that specifically addressed reliability: evolutionary design features supported by an extensive experience base; thoroughly tested components; and defense-in-depth mitigation of all identified failure mechanisms. The final proof test that the balance has been achieved is the application of the design, initially through lead use assemblies (LUAs), in a variety of plants that reflect the diversity of the BWR fleet. Regular detailed surveillance of these bundles provides the verification that the proper balance between performance and reliability has been achieved. GNF currently has GNF2 lead use assemblies operating in five plants. Included are plants that have implemented extended power up-rates, plants on one and two-year operating cycles, and plants with and without NobleChem TM and zinc injection. The leading plant has undergone three pool-side inspections outages to date. This paper reviews the actions taken to insure GNF2's reliability, and the lead use assembly surveillance data accumulated to date to validate

  9. FFTF operational experience

    Newland, D.J.; Krupar, J.J.

    1984-01-01

    In April 1982, the FFTF began its first nominally 100 day irradiation cycle. Since that time the plant has operated very well with steadily increasing plant capacity factors during its first four cycles. One hundred fifty fuel assemblies (eighty of which are experiments) and over 32,000 individual fuel pins have been irradiated, some in excess of 100 MWd/Kg burnup. Specialized equipment and systems unique to sodium cooled reactor plants have performed well

  10. Operating experience in reprocessing

    Schueller, W.

    1983-01-01

    Since 1953, reprocessing has accumulated 180 years of operating experience in ten plants, six of them with 41 years of operation in reprocessing oxide fuel from light water reactors. After abortive, premature attempts at what is called commercial reprocessing, which had been oriented towards the market value of recoverable uranium and plutonium, non-military reprocessing technologies have proved their technical feasibility, since 1966 on a pilot scale and since 1976 on an industrial scale. Reprocessing experience obtained on uranium metal fuel with low and medium burnups can now certainly be extrapolated to oxide fuel with high burnup and from pilot plants to industrial scale plants using the same technologies. The perspectives of waste management of the nuclear power plants operated in the Federal Republic of Germany should be viewed realistically. The technical problems still to be solved are in a balanced relationship to the benefit arising to the national economy out of nuclear power generation and can be solved in time, provided there are clearcut political boundary conditions. (orig.) [de

  11. Operating experience at CEBAF

    Legg, R.

    1996-01-01

    CEBAF, the Continuous Electron Beam Accelerator Facility, is a 5-pass, recirculating, superconducting rf linac designed to provide exceptional beam quality at 4 GeV up to 200 μA CW. It is made up of an injector, two 400-MeV linacs, and 9 recirculation arcs having a total beamline length of more than 4.5 km. On Nov. 5, 1995, CEBAF delivered a 4 GeV, 25-μA CW electron beam to the first of 3 experimental halls and the experimental physics program was started 10 days later. Accelerator availability during the first month of the experimental run exceeded 75%. Beam properties measured in the experimental hall to date are a one sigma momentum spread of 5x10 -5 and an rms emittance of 0.2 nanometer-radians, better than design specification. CW beam has been provided from all 5 passes at 800 MeV intervals. Outstanding performance of the superconducting linacs suggests a machine energy upgrade to 6 GeV in the near term with eventual machine operation at 8-10 GeV. Results from commissioning and operations experience since the last conference are presented

  12. Reviewing operational experience feedback

    1991-04-01

    The purpose of this document is to provide detailed supplementary guidance to OSART experts to aid in the evaluation of operational experience feedback (OEF) programmes at nuclear power plants. The document begins by describing the objectives of an OEF programme. It goes on to indicate preparatory work and investigatory guidance for the expert. Section 5 describes attributes of an excellent OEF programme. Appended to these guidelines are examples of OEF documents from various plants. These are intended to help the expert by demonstrating the actual implementation of OEF in practice. These guidelines are in no way intended to conflict with existing national regulations and rules. A comprehensive OEF programme, as described in Section 2, would be impossible to evaluated in detail in the amount of time typically allocated for assessing OEF in an OSART review. The expert must use his or her time wisely by concentrating on those areas that appear to be the weakest

  13. Tevatron operational experiences

    Norris, B.L.; Theilacker, J.C.

    1989-02-01

    Fermilabs superconducting accelerator, the Tevatron has been operational for nearly six years. The history of its operation is presented. Several long shutdowns for superconducting dipole repairs are discussed. The dominant factor influencing the repair was conductor motion which fatigued the cable in the magnet ends. Borescoping and x-raying techniques were used to determine which magnet ends required repair. Detailed downtime logs were kept for each of the running periods. A discussion of the sources of downtime and a comparison for different operating modes is presented

  14. TRIGA reactor operating experience

    Anderson, T.V.

    1970-01-01

    The Oregon State TRIGA Reactor (OSTR) has been in operation 3 years. Last August it was upgraded from 250 kW to 1000 kW. This was accomplished with little difficulty. During the 3 years of operation no major problems have been experienced. Most of the problems have been minor in nature and easily corrected. They came from lazy susan (dry bearing), Westronics Recorder (dead spots in the range), The Reg Rod Magnet Lead-in Circuit (a new type lead-in wire that does not require the lead-in cord to coil during rod withdrawal hss been delivered, much better than the original) and other small corrections

  15. Operating experience feedback in TVO

    Piirto, A [Teollisuuden Voima Oy (Finland)

    1997-12-31

    TVO is a power company operating with two 710 MW BWR units at Olkiluoto. For operating experience feedback TVO has not established a separate organizational unit but rather relies on a group of persons representing various technical disciplines. The ``Operating Experience Group`` meets at about three-week intervals to handle the reports of events (in plant and external) which have been selected for handling by an engineer responsible for experience feedback. 7 charts.

  16. Operating Experience at NPP Krsko

    Kavsek, D.; Bach, B.

    1998-01-01

    Systematic analysis of operational experience by assessment of internal and industry events and the feedback of lessons learned is one of the essential activities in the improvement of the operational safety and reliability of the nuclear power plant. At NPP Krsko we have developed a document called ''Operating Experience Assessment Program''. Its purpose is to establish administrative guidance for the processing of operating events including on-site and industry events. Assessment of internal events is based on the following methods: Event and Causal Factor Charting, Change Analysis, Barrier Analysis, MORT (Management Oversight and Risk Tree Analysis) and Human Performance Evaluation. The operating experience group has developed a sophisticated program entitled ''Operating experience tracking system'' (OETS) in response to the need for a more efficient way of processing internal and industry operating experience information. The Operating Experience Tracking System is used to initiate and track operational events including recommended actions follow up. Six screens of the system contain diverse essential information which allows tracking of operational events and enables different kinds of browsing. OETS is a part of the NPP Krsko nuclear network system and can be easily accessed by all plant personnel. (author)

  17. NPD Operating Experience

    Horton, E. P. [Hydro-Electric Power Commission of Ontario, Rolphton, ON (Canada)

    1968-04-15

    NPD has demonstrated high-capacity factor operation and for the past three years has achieved an average net capacity factor of 98% for the ''winter-peak'' period. The net capacity factor for the year 1966 was 88% and for the period from the end of commissioning (October 1962) to the end of 1966 was 71%. The output of the station has been stretched from 22 MW(e) gross to 25 MW(e) gross. This was aided by the installation of an internal steam separator in the turbine but no basic modifications to the reactor-boiler systems were required. The turbine has also been modified by the installation of chrome steel diaphragms as a solution to an erosion problem. The station also continues as a test facility to develop new components and techniques. This includes the recent successful replacement of two reactor pressure tubes and the conversion of the reactor vault ventilation system to a ''dry'' atmosphere using a molecular sieve to collect heavy-water leakage and control the concentration of acidic oxides of nitrogen. Fuel performance has been excellent and the average burn-up in the core is now 84 MWh/kg U which is slightly above the equilibrium design value. Only three fuel bundles have been found with sheath failures and none of these was due to a deficiency in the fuel but was as a result of handling problems with the refuelling equipment. In spite of undesirably high maintenance time, the fuelling machines have now inserted over 1000 fuel bundles into the reactor ''on power''. Heavy-water loss rates have been acceptable and are improving. The average loss rate from leaks during 1966 was 210 g/h. A proposal to modify the NPD heavy-water heat transport system to allow boiling is under consideration. (author)

  18. Ontario Hydro CANDU operating experience

    Jackson, H.A.; Woodhead, L.W.; Fanjoy, G.R.

    1984-03-01

    The CANDU Pressurized Heavy Water (CANDU-PHW) type of nuclear-electric generating station has been developed jointly by Atomic Energy of Canada Limited and Ontario Hydro. This report highlights Ontario Hydro's operating experience using the CANDU-PHW system, with a focus on the operating performance and costs, reliability of system components and nuclear safety considerations for the workers and the public

  19. Ontario Hydro CANDU operating experience

    Bartholomew, R.W.; Woodhead, L.W.; Horton, E.P.; Nichols, M.J.; Daly, I.N.

    1987-01-01

    The CANDU Pressurized Heavy Water (CANDU-PHW) type of nuclear-electric generating station has been developed jointly by Atomic Energy of Canada Limited and Ontario Hydro. This report highlights Ontario Hydro's operating experience using the CANDU-PHW system, with a focus on worker and public safety, operating performance and costs, and reliability of system components

  20. Operating practical experience at Argentina

    Quihillalt, Oscar

    1997-01-01

    Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed

  1. ERB-II operating experience

    Smith, R.N.; Cissel, D.W.; Smith, R.R.

    1977-01-01

    As originally designed and operated, EBR-II successfully demonstrated the concept of a sodium-cooled fast breeder power plant with a closed fuel reprocessing cycle (mini-nuclear park). Subsequent operation has been as an irradiation facility, a role which will continue into the foreseeable future. Since the beginning of operation in 1961, operating experience of EBR-II has been very satisfactory. Most of the components and systems have performed well. In particular, the mechanical performance of heat-removal systems has been excellent. A review of the operating experience reveals that all the original design objectives have been successfully demonstrated. To date, no failures or incidents resulting in serious in-core or out-of-core consequences have occurred. No water-to-sodium leaks have been detected over the life of the plant. At the present time, the facility is operating very well and continuously except for short shutdowns required by maintenance, refueling, modification, and minor repair. A plant factor of 76.9% was achieved for the calendar year 1976

  2. Fort Saint Vrain operational experience

    Fuller, C.H.

    1989-01-01

    Fort St. Vrain (FSV), on the system of the Public Service Company of Colorado, is the only high temperature gas-cooled (HTGR) power reactor in the United States. The plant features a helium-cooled reactor with a uranium-thorium fuel cycle. The paper describes the experience made during its operation. (author). 2 refs, 4 figs, 2 tabs

  3. Comparing PRAs with operating experience

    Picard, R.R.; Martz, H.F.

    1998-01-01

    Probabilistic Risk Assessment is widely used to estimate the frequencies of rare events, such as nuclear power plant accidents. An obvious question concerns the extent to which PRAs conform to operating experience--that is, do PRAs agree with reality? The authors discuss a formal methodology to address this issue and examine its performance using plant-specific data

  4. Emergency planning and operating experience

    Halpern, O.; Breniere, J.

    1984-01-01

    The purpose of this paper is to derive lessons from operating experience for the planning of emergency measures. This operating experience has two facets: it is obtained not only from the various incidents and accidents which have occurred in countries with nuclear power programmes and from the resulting application of emergency plans but also from the different exercises and simulations carried out in France and in other countries. Experience generally confirms the main approaches selected for emergency plans. The lessons to be derived are of three types: first, it appears necessary to set forth precisely the responsibilities of each person involved in order to prevent a watering-down of decisions in the event of an accident; secondly, considerable improvements need to be made in the different communication networks to be used; and thirdly, small accidents with minor radiological consequences deserve as systematic and thorough an approach as large and more improbable accidents. (author)

  5. Operation experience at the UWTF

    Ueno, Kazuhiro; Inada, Kameji; Ohmori, Kouji; Usui, Kazuya; Irinouchi, Sigenori; Asami, Makoto; Tohchi, Katsunori

    2003-01-01

    This report describes the operation experience on the volume reduction of metal wastes and used air filters contaminated with uranium at the Uranium contaminated Waste Treatment Facility (UWTF) in JNC Tokai Works. The UWTF consists of the metal waste treatment system and the filter-waste treatment system. The former treats metal wastes, the latter treats used air filters. Metal wastes are unpacked from drums, cut, and then compacted. Used air filters are separated into filter media and frames. Then the filter media are compacted and the frames are crushed. The operation of the UWTF was started in June 1998. The following volumes of wastes had been treated at the UWTF from the beginning of the operation to March 2003 (for about 5 years). (1) 1,524 drums of the metal wastes had been reduced to 410 drums. The volume reduction factor was 3.7. (2) 372 drums of the used air filters had been reduced to 39 drums. The volume reduction factor was 9.5. These systems have been operated without trouble for 5 years and have demonstrated to be able to reduce the volumes of the wastes to designed values. The volume reduction technologies for metal wastes and used air filters contaminated with uranium were successfully demonstrated at the UWTF. (author)

  6. ATLAS Pixel Detector Operational Experience

    Di Girolamo, B; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.9% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  7. Operation experience with elevated ammonia

    Vankova, Katerina; Kysela, Jan; Malac, Miroslav; Petrecky, Igor; Svarc, Vladimir

    2011-01-01

    The 10 VVER units in the Czech and Slovak Republics are all in very good water chemistry and radiation condition, yet questions have arisen regarding the optimization of cycle chemistry and improved operation in these units. To address these issues, a comprehensive experimental program for different water chemistries of the primary circuit was carried out at the Rez Nuclear Research Institute, Czech Republic, with the goal of judging the influence of various water chemistries on radiation build-up. Four types of water chemistries were compared: standard VVER water chemistry (in common use), direct hydrogen dosing without ammonia, standard VVER water chemistry with elevated ammonia levels, and zinc dosing to standard VVER water chemistry. The test results showed that the types of water chemistry other than the common one have benefits for the operation of the nuclear power plant (NPP) primary circuit. Operation experience with elevated ammonia at NPP Dukovany Units 3 and 4 is presented which validates the experimental results, demonstrating improved corrosion product volume activity. (orig.)

  8. Nuclear units operating improvement by using operating experience

    Rotaru, I.; Bilegan, I.C.

    1997-01-01

    The paper presents how the information experience can be used to improve the operation of nuclear units. This areas include the following items: conservative decision making; supervisory oversight; teamwork; control room distraction; communications; expectations and standards; operator training and fundamental knowledge, procedure quality and adherence; plant status awareness. For each of these topics, the information illustrate which are the principles, the lessons learned from operating experience and the most appropriate exemplifying documents. (authors)

  9. Stack Monitor Operating Experience Review

    Cadwallader, L.C.; Bruyere, S.A.

    2009-01-01

    Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative 'all modes' failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.

  10. Regulatory challenges in using nuclear operating experience

    2006-01-01

    There can be no doubt that the systematic evaluation of operating experience by the operator and the regulator is essential for continued safe operation of nuclear power plants. Recent concerns have been voiced that the operating experience information and insights are not being used effectively to promote safety. If these concerns foreshadow a real trend in OECD countries toward complacency in reporting and analysing operating events and taking corrective actions, then past experience suggests that similar or even more serious events will recur. This report discusses how the regulator can take actions to assure that operators have effective programmes to collect and analyse operating experience and, just as important, for taking steps to follow up with actions to prevent the events and conditions from recurring. These regulatory actions include special inspections of an operator operating experience programme and discussion with senior plant managers to emphasize the importance of having an effective operating experience programme. In addition to overseeing the operator programmes, the regulator has the broader responsibility for assuring that industry-wide trends, both national and international are monitored. To meet these responsibilities, the regulatory body must have its own operating experience programme, and this report discusses the important attributes of such regulatory programmes. It is especially important for the regulator to have the capability for assessing the full scope of operating experience issues, including those that may not be included in an operator operating experience programme, such as new research results, international operating experience, and broad industry trend information. (author)

  11. BWR and ABWR operating experience

    Nagai, Kimio; Takayama, Yoshito; Shimizu, Shunichi

    1998-01-01

    The first commercial operation of a nuclear power plant in Japan was in 1969. At present, there are 52 nuclear power plants operating in the country, accounting for about 35% of the total electricity generated and about 20 % of the total capacity of electricity generation facilities in Japan. Moreover, Japan has had the highest facility utilization rate, which is an indicator of operational safety, among the top four nuclear-generation countries (U.S.A., France, Germany, and Japan) every year since 1993, and has maintained a utilization rate of more than 80% since 1995. Toshiba has supported plant operation and maintenance in 19 nuclear power plants. The overall facility utilization rate of these plants attained a record of 86.4% in fiscal 1996. Furthermore, the averaged rates over the past three fiscal years from 1995 to 1997 have been the highest in the world among plant constructors such as GE, WH, and Siemens. (author)

  12. EBR-II operating experience

    Smith, C.R.F.

    1978-07-01

    Operation of the EBR-2 reactor is presented concerning the performance of the heat removal system; reactor materials; fuel handling system; sodium purification and sampling system; cover-gas purification; plant diagnostics and instrumentation; recent improvements in identifying fission product sources in EBR-2; and EBR-2 safety

  13. Recent U.S. reactor operating experience

    Stello, V. Jr.

    1977-01-01

    A qualitative assessment of U.S. and foreign reactor operating experience is provided. Recent operating occurrences having potentially significant safety impacts on power operation are described. An evaluation of the seriousness of each of these issues and the plans for resolution is discussed. A quantitative report on U.S. reactor operational experience is included. The details of the NRC program for evaluating and applying operating reactor experience in the regulatory process is discussed. A review is made of the adequacy of operating reactor safety and environmental margins based on actual operating experience. The Regulatory response philosophy to operating reactor experiences is detailed. This discussion indicates the NRC emphasis on the importance of a balanced action plan to provide for the protection of public safety in the national interest

  14. Reactor operator screening test experiences

    O'Brien, W.J.; Penkala, J.L.; Witzig, W.F.

    1976-01-01

    When it became apparent to Duquesne Light Company of Pittsburgh, Pennsylvania, that the throughput of their candidate selection-Phase I training-reactor operator certification sequence was something short of acceptable, the utility decided to ask consultants to make recommendations with respect to candidate selection procedures. The recommendation implemented was to create a Nuclear Training Test that would predict the success of a candidate in completing Phase I training and subsequently qualify for reactor operator certification. The mechanics involved in developing and calibrating the Nuclear Training Test are described. An arbitration decision that resulted when a number of International Brotherhood of Electrical Workers union employees filed a grievance alleging that the selection examination was unfair, invalid, not job related, inappropriate, and discriminatorily evaluated is also discussed. The arbitration decision favored the use of the Nuclear Training Test

  15. Experiences of an operating association

    Zefferer, H.

    1994-01-01

    The Austrian Draukraftwerke operate a coal power station with a capacity 110 MW el at St. Andraein Kaernten. In 1989, the first stage of a scheme for supplying the town St. Andraewith long-distance energy was started from this power station. To provide for the intermittent downtimes between the plant's operating times, which total an annual 2000 hours, a substitute aggregate was designed consisting of two biomass (chiefly bark)-fueled grate-firing boilers (4 MW th and 2.5 MW th ). The problems that arose during the first years in the areas of biomass storage, conveyor systems, slagging, emission values, and ash removal have meanwhile been solved satisfactorily. Moreover, the Draukraftwerke intend to use biomass for electricity generation in their coal power stations. (orig.) [de

  16. Operating experience feedback program at Olkiluoto NPP

    Kosonen, Mikko

    2002-01-01

    Recent review and development of the operating experience feedback program will be described. The development of the program has been based on several reviews by outside organizations. Main conclusions from these review reports and from the self assessment of safety performance, safety problems and safety culture on the basis of the operational events made by ASSET-method will be described. An approach to gather and analyze small events - so-called near misses - will be described. The operating experience program has been divided into internal and external operating experience. ASSET-methodology and a computer program assisting the analysis are used for the internal operating experience events. Noteworthy incidents occurred during outage are analyzed also by ASSET-method. Screening and pre analysis of the external operating experience relies on co-operation with ERFATOM, an organization of Nordic utilities for the exchange of nuclear industry experience. A short presentation on the performance of the Olkiluoto units will conclude the presentation. (author)

  17. Operational experience with superconducting synchrotron magnets

    Martin, P.S.

    1987-03-01

    The operational experience with the Fermilab Tevatron is presented, with emphasis on reliability and failure modes. Comprisons are made between the operating efficiencies for the superconducting machine and for he conventional Main Ring

  18. Operational experience with superconducting synchrotron magnets

    Martin, P.S.

    1987-01-01

    The operational experience with the Fermilab Tevatron is presented, with emphasis on reliability and failure modes. Comparisons are made between the operating efficiencies for the superconducting machine and for the conventional Main Ring

  19. Operational experience in underwater photogrammetry

    Leatherdale, John D.; John Turner, D.

    Underwater photogrammetry has become established as a cost-effective technique for inspection and maintenance of platforms and pipelines for the offshore oil industry. A commercial service based in Scotland operates in the North Sea, USA, Brazil, West Africa and Australia. 70 mm cameras and flash units are built for the purpose and analytical plotters and computer graphics systems are used for photogrammetric measurement and analysis of damage, corrosion, weld failures and redesign of underwater structures. Users are seeking simple, low-cost systems for photogrammetric analysis which their engineers can use themselves.

  20. US remote monitoring operational experience

    Dupree, S.A.; Sonnier, C.S.

    1997-01-01

    Under international partnerships and bilateral agreements with the U.S. Department of Energy, Sandia National Laboratories, other national laboratories, and international partner organizations have emplaced remote monitoring systems in nuclear facilities and laboratories in various parts of the world for the purpose of conducting field trials of remote monitoring. The purpose of the present report is to review the results from these field trials and draw general conclusions regarding the trials. Many thousands of hours of sensor and system operation have been logged, and data have been retrieved from many locations. In virtually all cases the system components have functioned as intended and data have been successfully collected and transmitted for review. Comparisons between front-end-triggered video and time-lapse video have shown that the triggered record has captured all relevant monitored operations at the various nuclear facilities included in the field trials. We believe the utility and functional reliability of remote monitoring for international safeguards has been shown. However, it should be kept in mind that openness and transparency, including some form of short-notice inspections, are likely to be prerequisites to the safeguards implementation of remote monitoring in any State

  1. The Wonderland of Operating the ALICE Experiment

    Augustinus, A; Pinazza, O; Rosinský, P; Lechman, M; Jirdén, L; Chochula, P

    2011-01-01

    ALICE is one of the experiments at the Large Hadron Collider (LHC), CERN, Geneva, Switzerland. Composed of 18 sub-detectors each with numerous subsystems that need to be controlled and operated in a safe and efficient way. The Detector Control System (DCS) is the key to this and has been used by detector experts with success during the commissioning of the individual detectors. During the transition from commissioning to operation, more and more tasks were transferred from detector experts to central operators. By the end of the 2010 datataking campaign, the ALICE experiment was run by a small crew of central operators, with only a single controls operator. The transition from expert to non-expert operation constituted a real challenge in terms of tools, documentation and training. A relatively high turnover and diversity in the operator crew that is specific to the HEP experiment environment (as opposed to the more stable operation crews for accelerators) made this challenge even bigger. Thi...

  2. Magnet operating experience review for fusion applications

    Cadwallader, L.C.

    1991-11-01

    This report presents a review of magnet operating experiences for normal-conducting and superconducting magnets from fusion, particle accelerator, medical technology, and magnetohydrodynamics research areas. Safety relevant magnet operating experiences are presented to provide feedback on field performance of existing designs and to point out the operational safety concerns. Quantitative estimates of magnet component failure rates and accident event frequencies are also presented, based on field experience and on performance of similar components in other industries

  3. Operator training and the training simulator experience

    Mills, D.

    The author outlines the approach used by Ontario Hydro to train operators from the day they are hired as Operators-in-Training until they are Authorized Unit First Operators. He describes in detail the use of the simulator in the final year of the authorization program, drawing on experience with the Pickering NGS A simulator. Simulators, he concludes, are important aids to training but by no means all that is required to guarantee capable First Operators

  4. Operating manual for the critical experiments facility

    1986-01-01

    The operation of the Critical Experiments Facility (CEF) requires careful attention to procedures in order that all safety precautions are observed. Since an accident could release large amounts of radioactivity, careful operation and strict enforcement of procedures are necessary. To provide for safe operation, detailed procedures have been written for all phases of the operation of this facility. The CEF operating procedures are not to be construed to constitute a part ofthe Technical Specifications. In the event of any discrepancy between the information given herein and the Technical Specifications, limits set forth in the Technical Specifications apply. All normal and most emergency operation conditions are covered by procedures presented in this manual. These procedures are designed to be followed by the operating personnel. Strict adherence to these procedures is expected for the following reasons. (1) To provide a standard, safe method of performing all operations, the procedures were written by reactor engineers experienced in supervising the operation of reactors and were reviewed by an organization with over 30 years of reactor operating experience. (2) To have an up-to-date description of operating techniques available at all times for reference and review, it is necessary that the procedures be written

  5. Operating manual for the critical experiments facility

    1986-01-01

    The operation of the Critical Experiments Facility (CEF) requires careful attention to procedures in order that all safety precautions are observed. Since an accident could release large amounts of radioactivity, careful operation and strict enforcement of procedures are necessary. To provide for safe operation, detailed procedures have been written for all phases of the operation of this facility. The CEF operating procedures are not to be construed to constitute a part ofthe Technical Specifications. In the event of any discrepancy between the information given herein and the Technical Specifications, limits set forth in the Technical Specifications apply. All normal and most emergency operation conditions are covered by procedures presented in this manual. These procedures are designed to be followed by the operating personnel. Strict adherence to these procedures is expected for the following reasons. (1) To provide a standard, safe method of performing all operations, the procedures were written by reactor engineers experienced in supervising the operation of reactors and were reviewed by an organization with over 30 years of reactor operating experience. (2) To have an up-to-date description of operating techniques available at all times for reference and review, it is necessary that the procedures be written.

  6. Industry Operating Experience Process at Krsko NPP

    Bach, B.; Bozin, B.; Cizmek, R.

    2012-01-01

    Experience has shown that number of minor events and near misses, usually without immediate or significant impact to plant safety and reliability, are precursors of significant or severe events due to the same or similar root or apparent cause(s). It is therefore desirable to identify and analyze weaknesses of the precursor problems (events) in order to prevent occurrence of significant events. Theoretically, significant events could be prevented from occurring if the root cause(s) of these precursor problems could be identified and eliminated. The Operating Experience Program identifies such event precursors and by reporting them to the industry, plant specific corrective actions can be taken to prevent events at other operational plants. The intent of the Operating Experience Program is therefore to improve nuclear power plant safety and reliability of the operating nuclear power plants. Each plant develops its own Operating Experience Program in order to learn from the in-house operating experience as well as from the world community of nuclear plants. The effective use of operating experience includes analyzing both plant and industry events in order to identify fundamental weaknesses and then determining appropriate plant-specific actions that will minimize the likelihood of similar events. Learning and applying the lessons from operating experience is an integral part of station safety culture and is encouraged by managers throughout the top plant administrative programs and procedures. Krsko NPP is developed it own Operating Experience Program by using the most relevant INPO/WANO/IAEA guidelines as well as its own knowledge, skills an operating practice. The Operating Experience Program is a part of the Corrective Action Program, which is among top management programs, thus program is strongly encouraged by top management. The purpose of Operating Experience Program is to provide guidance for using, sharing, and evaluating operating experience information

  7. 14 CFR 121.434 - Operating experience, operating cycles, and consolidation of knowledge and skills.

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Operating experience, operating cycles, and... Qualifications § 121.434 Operating experience, operating cycles, and consolidation of knowledge and skills. (a... position, the operating experience, operating cycles, and the line operating flight time for consolidation...

  8. Operational experience of the Marcoule reactors

    Conte, F.

    1963-01-01

    The results obtaining from three years operation of the reactors G-2, G-3 have made it possible to accumulate a considerable amount of operational experience of these reactors. The main original points: - the pre-stressed concrete casing - the possibility of loading while under power - automatic temperature control have been perfectly justified by the results of operation. The author confirms the importance of these original solutions and draws conclusions concerning the study of future nuclear power stations. (author) [fr

  9. MIT January Operational Internship Experience 2011

    DeLatte, Danielle; Furhmann, Adam; Habib, Manal; Joujon-Roche, Cecily; Opara, Nnaemeka; Pasterski, Sabrina Gonzalez; Powell, Christina; Wimmer, Andrew

    2011-01-01

    This slide presentation reviews the 2011 January Operational Internship experience (JOIE) program which allows students to study operational aspects of spaceflight, how design affects operations and systems engineering in practice for 3 weeks. Topics include: (1) Systems Engineering (2) NASA Organization (3) Workforce Core Values (4) Human Factors (5) Safety (6) Lean Engineering (7) NASA Now (8) Press, Media, and Outreach and (9) Future of Spaceflight.

  10. Regulatory challenges in using nuclear operating experience

    2006-01-01

    The fundamental objective of all nuclear safety regulatory bodies is to ensure that nuclear utilities operate their plants in an acceptably safe manner at all times. Learning from experience has been a key element in meeting this objective. It is therefore very important for nuclear power plant operators to have an active programme for collecting, analysing and acting on the lessons of operating experience that could affect the safety of their plants. NEA experts have noted that almost all of the recent, significant events reported at international meetings have occurred earlier in one form or another. Counteractions are usually well-known, but information does not always seem to reach end users, or corrective action programmes are not always rigorously applied. Thus, one of the challenges that needs to be met in order to maintain good operational safety performance is to ensure that operating experience is promptly reported to established reporting systems, preferably international in order to benefit from a larger base of experience, and that the lessons from operating experience are actually used to promote safety. This report focuses on how regulatory bodies can ensure that operating experience is used effectively to promote the safety of nuclear power plants. While directed at nuclear power plants, the principles in this report may apply to other nuclear facilities as well. (author)

  11. Experience in operation of heavy water reactors

    Rotaru, Ion; Bilegan, Iosif; Ghitescu, Petre

    1999-01-01

    The paper presents the main topics of the CANDU owners group (COG) meeting held in Mangalia, Romania on 7-10 September 1998. These meetings are part of the IAEA program for exchange of information related mainly to CANDU reactor operation safety. The first meeting for PHWR reactors took place in Vienna in 1989, followed by those in Argentina (1991), India (1994) and Korea (1996). The topics discussed at the meeting in Romania were: operation experience and recent major events, performances of CANDU reactors and safe operation, nuclear safety and operation procedures of PHWR, programs and strategies of lifetime management of installations and components of NPPs, developments and updates

  12. Medical supply on contingency military operations: experience from Operation GRITROCK.

    Robinson, J P; Reeves, P

    2015-01-01

    Medical supply during military operations has the ability to affect the efficacy of the operation being undertaken, either negatively or positively. An appropriately-managed maritime platform with a robust medical supply chain during transit and on arrival in theatre is the main aim. A secure supply chain will reduce any implications that logistics may have with regard to capability, and negate the effects of deficiencies of short shelf life items occurring over time and during use in high tempo operations.

  13. Operational experience with the Daresbury accelerator tube

    Aitken, T.W.; Eastham, D.A.; Joy, T.; Leese, J.M.; Tait, N.R.S.; Thorn, R.

    1986-01-01

    Operational experience with the Daresbury MKI accelerator tube is reviewed with particular attention to conditioning and high voltage performance. The effects of surges and transients on the tube are described and lines of future development are discussed. (orig.)

  14. Operating experience feedback report - Solenoid-operated valve problems

    Ornstein, H.L.

    1991-02-01

    This report highlights significant operating events involving observed or potential common-mode failures of solenoid-operated valves (SOVs) in US plants. These events resulted in degradation or malfunction of multiple trains of safety systems as well as of multiple safety systems. On the basis of the evaluation of these events, the Office for Analysis and Evaluation of Operational Data (AEOD) of the US Nuclear Regulatory Commission (NRC) concludes that the problems with solenoid-operated valves are an important issue that needs additional NRC and industry attention. This report also provides AEOD's recommendations for actions to reduce the occurrence of SOV common-mode failures. 115 refs., 7 figs., 2 tabs

  15. Operating experience and TPA: the Italian perspective

    Grimaldi, G.

    1990-01-01

    Collection and analysis of operating experience from the Italian plants and utilization of abroad data both to plants in operation and in construction are presented. Some results are also referred, aimed to evidence the role of the international cooperation to safe operation of nuclear plants. The approach to the Trend and Pattern analyses is described as well, and the use of computerized techniques of analysis on personal computer. Finally on going activities are introduced, specifically application of operating experience of plants in operation to small sized reactors and to ones with more intrinsic safety characteristics; review of the reporting system for future application and comparative analysis of the different realization of selected safety systems

  16. Kayenta advanced series compensation operational experience

    1994-01-01

    The world's first three-phase, thyristor-controlled series compensation scheme with continuously variable impedance has been introduced into a transmission system. Energized and dedicated in September 1992, the installation was placed into commercial operation in January 1993 and has provided over one year of operating experience. This paper describes the 230 kV, 330 MVAr (60 Hz) advanced series compensation (ASC) project, located in north-eastern Arizona at Kayenta Substation on the 320 km Glen Canyon-Shiprock transmission line. The paper describes operating experiences, coordination with phase shifting transformer, phase shifter failure, platform power, system disturbances, and future plans.

  17. Combining risk analysis and operating experience

    1986-10-01

    In recent years there has been an increasing interest in the systematic utilization of operating experience in the decision making process concerning large industrial facilities. Even before the advent of Probabilistic Safety Assessment (PSA), operating experience had always played an important role in such decisions. Of course, operating experience has always been an input to PSA also; however, as PSA becomes more mature and the quality and quantity of operating experience improve, greater emphasis is now being placed on the use of operating experience to update and validate PSA and thereby provide a more rational basis for decision making. This report outlines the ways in which data are collected, processed using mathematical techniques and utilized in decision making. It is not intended to provide details of the methods and procedures to be used in these areas, but is rather intended as an introduction to these topics and some of the relevant literature. The meeting presentations were divided into three sessions devoted to the following topics: evaluation of nuclear power plants operational experience (5 papers); uncertainties (2 papers); probabilistic safety assessment studies in Member States (7 papers). A separate abstract was prepared for each of these papers

  18. The SM and MIR reactors operation experience

    Kuprienko, V.A.; Klinov, A.V.; Svyatkin, M.N.; Shamardin, V.K.

    1995-01-01

    The SM and MIR operation experience show that continuous work on the problem of ageing, in all its aspects, allows for prolongation of the research plant life cycle by several folds as compared to the initial project. The redesigned SM-3 reactor will operate for another 20 years. The similar result is expected from the MIR planned reconstruction which scope will be the topic of future presentations. (orig.)

  19. Nuclear power plant operating experience, 1976

    1977-11-01

    This report is the third in a series of reports issued annually that summarize the operating experience of U.S. nuclear power plants in commercial operation. Power generation statistics, plant outages, reportable occurrences, fuel element performance, occupational radiation exposure and radioactive effluents for each plant are presented. Summary highlights of these areas are discussed. The report includes 1976 data from 55 plants--23 boiling water reactor plants and 32 pressurized water reactor plants

  20. HANARO operation experience in the year 2004

    Oh, Soo-Youl; Kim, Heonil; Cho, Yeong-Garp; Jun, Byung-Jin

    2006-01-01

    The experiences of the HANARO operation and maintenance in the year 2004 are presented in this article. The operation of HANARO, a 30 MW research reactor operated by the Korea Atomic Energy Research Institute (KAERI), aims at a safe and effective operation to enhance its utilization in various fields of scientific research and industry. Regardless of its importance of the routine operation, this article is devoted to rather unusual matters such as irregular maintenance events and incidents. Since the first criticality in 1995, it has been a long-cherished task to reach the designed power level of 30 MW from the temporarily approved 24 MW. By resolving the concern on the fuel integrity, the designed level could be licensed and, eventually, it was achieved last November. On the other hand, after its 9 years of operation, the mechanical integrity of the heavy water reflector tank was checked. The measurement of the vertical straightness of the tank inner shell indicated its integrity. Meanwhile, the HANARO fuel production facility was completed at the KAERI site, and it will begin to supply centrifugally atomized fuels, instead of conventional comminuted fuels, to HANARO shortly. There were several incidents in 2004, which have all been cleared, including a leak of heavy water, melting of a sample in an irradiation hole for the neutron activation analysis, and a condensation problem in a horizontal beam tube. The progress of and lessons from each incident are presented. The utilization of HANARO is expanding every year and the trend will also continue in 2005. The operation mode has been changed from an 18-day continuous operation and 10-day shutdown (18-10 mode) to the 23-12 mode since the end of 2004, and a further extension is planned to the 30-12 mode. Thanks to this extended operation term, an increased power level and, most importantly, a reliable operation, the HANARO is gaining more and more credit from the end users. (author)

  1. Operating experience insights supporting ageing assessments

    Nitoi, M.

    2013-01-01

    Be effective in ageing management means looking at the right aspects, with the right techniques, and one of the most effective tool which could be used for that purpose is the analysis of operating experience. The paper has as objective to perform a review of available operating experience, with the aim to provide a better picture about the impact of ageing effects. The IAEA International Reporting System and NRC Licensee Event Reports were chosen as reference databases, both databases being internationally recognized as important sources of information about events occurrences in the nuclear power plants. The ageing related events identified in the selected time window were analyzed in detail, and the contributions of each major degradation mechanisms that have induced the ageing related events (specific to each defined group of components) was represented and discussed. The paper demonstrates the possibility to use operating experience insights in highlighting the ageing effects. (authors)

  2. Operational experience with SLAC's beam containment electronics

    Constant, T.N.; Crook, K.; Heggie, D.

    1977-03-01

    Considerable operating experience was accumulated at SLAC with an extensive electronic system for the containment of high power accelerated beams. Average beam power at SLAC can approach 900 kilowatts with the potential for burning through beam stoppers, protection collimators, and other power absorbers within a few seconds. Fast, reliable, and redundant electronic monitoring circuits have been employed to provide some of the safeguards necessary for minimizing the risk to personnel. The electronic systems are described, and the design philosophy and operating experience are discussed

  3. LOFT instrumented fuel design and operating experience

    Russell, M.L.

    1979-01-01

    A summary description of the Loss-of-Fluid Test (LOFT) system instrumented core construction details and operating experience through reactor startup and loss-of-coolant experiment (LOCE) operations performed to date are discussed. The discussion includes details of the test instrumentation attachment to the fuel assembly, the structural response of the fuel modules to the forces generated by a double-ended break of a pressurized water reactor (PWR) coolant pipe at the inlet to the reactor vessel, the durability of the LOFT fuel and test instrumentation, and the plans for incorporation of improved fuel assembly test instrumentation features in the LOFT core

  4. Defense waste processing facility radioactive operations. Part 1 - operating experience

    Little, D.B.; Gee, J.T.; Barnes, W.M.

    1997-01-01

    The Savannah River Site's Defense Waste Processing Facility (DWPF) near Aiken, SC is the nation's first and the world's largest vitrification facility. Following a ten year construction program and a 3 year non-radioactive test program, DWPF began radioactive operations in March 1996. This paper presents the results of the first 9 months of radioactive operations. Topics include: operations of the remote processing equipment reliability, and decontamination facilities for the remote processing equipment. Key equipment discussed includes process pumps, telerobotic manipulators, infrared camera, Holledge trademark level gauges and in-cell (remote) cranes. Information is presented regarding equipment at the conclusion of the DWPF test program it also discussed, with special emphasis on agitator blades and cooling/heating coil wear. 3 refs., 4 figs

  5. Accelerator/Experiment operations - FY 2006

    Brice, S.; Conrad, J.; Denisov, D.; Ginther, G.; Holmes, S.; James, C.; Lee, W.; Louis, W.; Moore, C.; Plunkett, R.; Raja, R.; /Fermilab

    2006-10-01

    This Technical Memorandum (TM) summarizes the Fermilab accelerator and experiment operations for FY 2006. It is one of a series of annual publications intended to gather information in one place. In this case, the information concerns the FY 2006 Run II at the Tevatron Collider, the MiniBooNE experiments running in the Booster Neutrino Beam in neutrino and antineutrino modes, MINOS using the Main Injector Neutrino Beam (NuMI), and SY 120 activities.

  6. Operational experience of the ATLAS accelerator

    Den Hartog, P K; Bogaty, J M; Bollinger, L M; Clifft, B E; Craig, S L; Harden, R E; Markovich, P; Munson, F H; Nixon, J M; Pardo, R C; Phillips, D R; Shepard, K W; Tilbrook, I R; Zinkmann, G P [Argonne National Lab., IL (USA). Physics Div.

    1990-02-01

    The ATLAS accelerator consists of a HVEC model FN tandem accelerator injecting into a linac of independently-phased niobium superconducting resonators. The accelerator provides beams with masses 6 {le} A {le} 127 and with energies ranging up to 20 MeV/A for the lightest ions and 4 MeV/A for the heaviest ions. Portions of the linac have been in operation since 1978 and, over the last decade, more than 35000 h of operating experience have been accumulated. The long-term stability of niobium resonators, and their feasibility for use in heavy-ion accelerators is now well established. (orig.).

  7. Operational experience of extreme wind penetrations

    Estanqueiro, Ana [INETI/LNEG - National Laboratory for Energy and Geology, Lisbon (Portugal); Mateus, Carlos B. [Instituto de Meteorologia, Lisboa (Portugal); Pestana, Rui [Redes Energeticas Nacionais (REN), Lisboa (Portugal)

    2010-07-01

    This paper reports the operational experience from the Portuguese Power System during the 2009/2010 winter months when record wind penerations were observed: the instantaneous wind power penetration peaked at 70% of consumption during no-load periods and the wind energy accounted for more than 50% of the energy consumed for a large period. The regulation measures taken by the TSO are presented in the paper, together with the additional reserves operated for added system security. Information on the overall power system behavior under such extreme long-term wind power penetrations will also be addressed. (org.)

  8. Operating procedures: Fusion Experiments Analysis Facility

    Lerche, R.A.; Carey, R.W.

    1984-03-20

    The Fusion Experiments Analysis Facility (FEAF) is a computer facility based on a DEC VAX 11/780 computer. It became operational in late 1982. At that time two manuals were written to aid users and staff in their interactions with the facility. This manual is designed as a reference to assist the FEAF staff in carrying out their responsibilities. It is meant to supplement equipment and software manuals supplied by the vendors. Also this manual provides the FEAF staff with a set of consistent, written guidelines for the daily operation of the facility.

  9. Operating procedures: Fusion Experiments Analysis Facility

    Lerche, R.A.; Carey, R.W.

    1984-01-01

    The Fusion Experiments Analysis Facility (FEAF) is a computer facility based on a DEC VAX 11/780 computer. It became operational in late 1982. At that time two manuals were written to aid users and staff in their interactions with the facility. This manual is designed as a reference to assist the FEAF staff in carrying out their responsibilities. It is meant to supplement equipment and software manuals supplied by the vendors. Also this manual provides the FEAF staff with a set of consistent, written guidelines for the daily operation of the facility

  10. Preheat operating experiences at the FFTF

    Tucker, W.R.

    1978-01-01

    The rather extensive test program performed on the FFTF preheat control system resulted in successful sodium fill of one secondary heat transport loop on July 2, 1978. The data obtained during testing and the attendant operating experience gained resulted in some design changes and provided the information necessary to fully characterize system performance. Temperature excursions and deviations from preset limits of only a minor nature were encountered during preheat for sodium fill. The addition of the rate alarm feature was beneficial to operation of the preheat system and allowed early detection and correction of impending excursions

  11. Operational experience with CMS Tier-2 sites

    Gonzalez Caballero, I

    2010-01-01

    In the CMS computing model, more than one third of the computing resources are located at Tier-2 sites, which are distributed across the countries in the collaboration. These sites are the primary platform for user analyses; they host datasets that are created at Tier-1 sites, and users from all CMS institutes submit analysis jobs that run on those data through grid interfaces. They are also the primary resource for the production of large simulation samples for general use in the experiment. As a result, Tier-2 sites have an interesting mix of organized experiment-controlled activities and chaotic user-controlled activities. CMS currently operates about 40 Tier-2 sites in 22 countries, making the sites a far-flung computational and social network. We describe our operational experience with the sites, touching on our achievements, the lessons learned, and the challenges for the future.

  12. Operational Experience from Solar Thermal Energy Projects

    Cameron, C. P.

    1984-01-01

    Over the past few years, Sandia National Laboratories were involved in the design, construction, and operation of a number of DOE-sponsored solar thermal energy systems. Among the systems currently in operation are several industrial process heat projects and the Modular Industrial Solar Retrofit qualification test systems, all of which use parabolic troughs, and the Shenandoah Total Energy Project, which uses parabolic dishes. Operational experience has provided insight to both desirable and undesirable features of the designs of these systems. Features of these systems which are also relevant to the design of parabolic concentrator thermal electric systems are discussed. Other design features discussed are system control functions which were found to be especially convenient or effective, such as local concentrator controls, rainwash controls, and system response to changing isolation. Drive systems are also discussed with particular emphasis of the need for reliability and the usefulness of a manual drive capability.

  13. Accelerator/Experiment Operations - FY 2015

    Czarapata, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); et al.

    2015-10-01

    This Technical Memorandum summarizes the Fermilab accelerator and experiment operations for FY 2015. It is one of a series of annual publications intended to gather information in one place. In this case, the information concerns the FY 2015 NOvA, MINOS+ and MINERvA experiments using the Main Injector Neutrino Beam (NuMI), the activities in the SciBooNE Hall using the Booster Neutrino Beam (BNB), and the SeaQuest experiment and Meson Test Beam (MTest) activities in the 120 GeV external Switchyard beam (SY120).

  14. Operational experience feedback with precursor analysis

    Koncar, M.; Ferjancic, M.; Muehleisen, A.; Vojnovic, D.

    2003-01-01

    Experience of practical operation is a valuable source of information for improving the safety and reliability of nuclear power plants. Operational experience feedback (Olef) system manages this aspect of NPP operation. The traditional ways of investigating operational events, such as the root cause analysis (RCA), are predominantly qualitative. RCA as a part of the Olef system provides technical guidance and management expectations in the conduct of assessing the root cause to prevent recurrence, covering the following areas: conditions preceding the event, sequence of events, equipment performance and system response, human performance considerations, equipment failures, precursors to the event, plant response and follow-up, radiological considerations, regulatory process considerations and safety significance. The root cause of event is recognized when there is no known answer on question 'why has it happened?' regarding relevant condition that may have affected the event. At that point the Olef is proceeding by actions taken in response to events, utilization, dissemination and exchange of operating experience information and at the end reviewing the effectiveness of the Olef. Analysis of the event and the selection of recommended corrective/preventive actions for implementation and prioritization can be enhanced by taking into account the information and insights derived from Pasa-based analysis. A Pasa based method, called probabilistic precursor event analysis (PPE A) provides a complement to the RCA approach by focusing on how an event might have developed adversely, and implies the mapping of an operational event on a probabilistic risk model of the plant in order to obtain a quantitative assessment of the safety significance of the event PSA based event analysis provides, due to its quantitative nature, appropriate prioritization of corrective actions. PPEA defines requirements for PSA model and code, identifies input requirements and elaborates following

  15. Operational and reliability experience with reactor instrumentation

    Dixon, F.; Gow, R.S.

    1978-01-01

    In the last 15 years the CEGB has experienced progressive plant development, integration and changes in operating regime through nine nuclear (gas-cooled reactor) power stations with corresponding instrumentation advances leading towards more refined centralized control. Operation and reliability experience with reactor instrumentation is reported in this paper with reference to the progressive changes related to the early magnox, late magnox and AGR periods. Data on instrumentation reliability in terms of reactor forced outages are presented and show that the instrumentation contributions to loss of generating plant availability are small. Reactor safety circuits, neutron flux and temperature measurements, gas analysis and vibration monitoring are discussed. In reviewing the reactor instrumentation the emphasis is on reporting recent experience, particularly on AGR equipment, but overall performance and changes to magnox equipment are included so that some appreciation can be obtained of instrumentation requirements with respect to plant lifetimes. (author)

  16. Operational Experience with the ATLAS Pixel Detector

    Djama, Fares; The ATLAS collaboration

    2017-01-01

    Run 2 of the LHC collider sets new challenges to track and vertex reconstruction because of its higher energy, pileup and luminosity. The ATLAS tracking performance relies critically on the Pixel Detector. Therefore, in view of Run 2, the ATLAS collaboration has constructed the first 4-layer pixel detector in Particle Physics by installing a new pixel layer, called Insertable B-Layer (IBL). Operational experience and performance of the 4-layer Pixel Detector during Run 2 are presented.

  17. Continuous Air Monitor Operating Experience Review

    Cadwallader, L.C.; Bruyere, S.A.

    2008-01-01

    Continuous air monitors (CAMs) are used to sense radioactive particulates in room air of nuclear facilities. CAMs alert personnel of potential inhalation exposures to radionuclides and can also actuate room ventilation isolation for public and environmental protection. This paper presents the results of a CAM operating experience review of the DOE Occurrence Reporting and Processing System (ORPS) database from the past 18 years. Regulations regarding these monitors are briefly reviewed. CAM location selection and operation are briefly discussed. Operating experiences reported by the U.S. Department of Energy and in other literature sources were reviewed to determine the strengths and weaknesses of these monitors. Power losses, human errors, and mechanical issues cause the majority of failures. The average 'all modes' failure rate is 2.65E-05/hr. Repair time estimates vary from an average repair time of 9 hours (with spare parts on hand) to 252 hours (without spare parts on hand). These data should support the use of CAMs in any nuclear facility, including the National Ignition Facility and the international ITER experiment

  18. Accelerator/Experiment Operations - FY 2016

    Blake, A.; Convery, M.; Geer, S.; Geesaman, D.; Harris, D.; Johnson, D.; Lang, K.; McFarland, K.; Messier, M.; Moore, C. D.; Newhart, D.; Reimer, P. E.; Plunkett, R.; Rominsky, M.; Sanchez, M.; Schmidt, J. J.; Shanahan, P.; Tate, C.; Thomas, J.; Donatella Torretta, Donatella Torretta; Matthew Wetstein, Matthew Wetstein

    2016-01-01

    This Technical Memorandum summarizes the Fermilab accelerator and experiment operations for FY 2016. It is one of a series of annual publications intended to gather information in one place. In this case, the information concerns the FY 2016 NOvA, MINOS+ and MINERvA experiments using the Main Injector Neutrino Beam (NuMI), the MicroBooNE experiment and the activities in the SciBooNE Hall using the Booster Neutrino Beam (BNB), and the SeaQuest experiment, LArIAT experiment and Meson Test Beam activities in the 120 GeV external switchyard beam (SY120). Each section was prepared by the relevant authors, and was then edited for inclusion in this summary.

  19. Accelerator/Experiment Operations - FY 2016

    Blake, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Convery, M. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Geer, S. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Geesaman, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Harris, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Johnson, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lang, K. [Argonne National Lab. (ANL), Argonne, IL (United States); McFarland, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Messier, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Moore, C. D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Newhart, D. [Fermilab; Reimer, P. E. [Argonne; Plunkett, R. [Fermilab; Rominsky, M. [Fermilab; Sanchez, M. [Iowa State U.; Schmidt, J. J. [Fermilab; Shanahan, P. [Fermilab; Tate, C. [Fermilab; Thomas, J. [University Coll. London; Donatella Torretta, Donatella Torretta [Fermilab; Matthew Wetstein, Matthew Wetstein [Iowa State University

    2016-10-01

    This Technical Memorandum summarizes the Fermilab accelerator and experiment operations for FY 2016. It is one of a series of annual publications intended to gather information in one place. In this case, the information concerns the FY 2016 NOvA, MINOS+ and MINERvA experiments using the Main Injector Neutrino Beam (NuMI), the MicroBooNE experiment and the activities in the SciBooNE Hall using the Booster Neutrino Beam (BNB), and the SeaQuest experiment, LArIAT experiment and Meson Test Beam activities in the 120 GeV external switchyard beam (SY120). Each section was prepared by the relevant authors, and was then edited for inclusion in this summary.

  20. Simulator experiments: effects of NPP operator experience on performance

    Beare, A.N.; Gray, L.H.

    1985-01-01

    Experiments are being conducted on nuclear power plant (NPP) control room training simulators by the Oak Ridge National Laboratory, its subcontractor, General Physics Corporation, and participating utilities. The experiments are sponsored by the Nuclear Regulatory Commission's (NRC) Human Factors and Safeguards Branch, Division of Risk Analysis and Operations, and are a continuation of prior research using simulators, supported by field data collection, to provide a technical basis for NRC human factors regulatory issues concerned with the operational safety of nuclear power plants. During the FY83 research, a simulator experiment was conducted at the control room simulator for a GE boiling water reactor (BWR) NPP. The research subjects were licensed operators undergoing requalification training and shift technical advisors (STAs). This experiment was designed to investigate the effects of (a) senior reactor operator (SRO) experience, (b) operating crew augmentation with an STA and (c) practice, as a crew, upon crew and individual operator performance, in response to anticipated plant transients. The FY84 experiments are a partial replication and extension of the FY83 experiment, but with PWR operators and simulator. Methodology and results to date are reported

  1. Tritium Room Air Monitor Operating Experience Review

    L. C. Cadwallader; B. J. Denny

    2008-09-01

    Monitoring the breathing air in tritium facility rooms for airborne tritium is a radiological safety requirement and a best practice for personnel safety. Besides audible alarms for room evacuation, these monitors often send signals for process shutdown, ventilation isolation, and cleanup system actuation to mitigate releases and prevent tritium spread to the environment. Therefore, these monitors are important not only to personnel safety but also to public safety and environmental protection. This paper presents an operating experience review of tritium monitor performance on demand during small (1 mCi to 1 Ci) operational releases, and intentional airborne inroom tritium release tests. The tritium tests provide monitor operation data to allow calculation of a statistical estimate for the reliability of monitors annunciating in actual tritium gas airborne release situations. The data show a failure to operate rate of 3.5E-06/monitor-hr with an upper bound of 4.7E-06, a failure to alarm on demand rate of 1.4E-02/demand with an upper bound of 4.4E-02, and a spurious alarm rate of 0.1 to 0.2/monitor-yr.

  2. Operational experience of the ATLAS accelerator

    Den Hartog, P.K.; Bogaty, J.M.; Bollinger, L.M.

    1989-01-01

    The ATLAS accelerator consists of a HVEC model FN tandem accelerator injecting into a linac of independently-phased niobium superconducting resonators. The accelerator provides beams with masses from 6≤A≤127 and with energies ranging up to 20 MeV/A for the lightest ions and 4 MeV/A for the heaviest ions. Portions of the linac have been in operation since 1978 and, over the last decade, more than 35,000 hours of operating experience have been accumulated. The long-term stability of niobium resonators, and their feasibility for use in heavy-ion accelerators is now well established. 11 refs., 3 figs., 1 tab

  3. Operating experiences with 1 MW steam generator

    Sano, A; Kanamori, A; Tsuchiya, T

    1975-07-01

    1 MW steam generator, which was planned as the first stage of steam generator development in Power Reactor and Nuclear Fuel Corp. (PNC) in Japan, is a single-unit, once-through, integrated shell and tube type with multi-helical coil tubes. It was completed in Oarai Engineering Center of PNC in March of 1971, and the various performance tests were carried out up to April, 1972. After the dismantle of the steam generator for structural inspection and material test, it was restored with some improvements. In this second 1 MW steam generator, small leak occurred twice during normal operation. After repairing the failure, the same kind of performance tests as the first steam generator were conducted in order to verify the thermal insulation effect of argon gas in downcomer zone from March to June, 1974. In this paper the above operating experiences were presented including the outline of some performance test results. (author)

  4. Selection of operations staff, qualifications and experience

    Gutmann, H.

    1977-01-01

    Requirements and suggestions have been made by authorities and various organisations in a number of countries which define necessary experience and training for the various groups of nuclear power plant personnel. For two countries, the USA and the FRG, a comparison has been made which shows that there is only a slight deviation, taking into account the different education systems. With the example of the Biblis nuclear power plant the training on the job is described. Especially the production or operation department is looked at in more detail. The training is split up into several parts: a general part, such as nuclear physics, reactor physics and engineering, reactor safety, radiation protection and so on and a plant related part, such as arrangement and mode of operation of the plant under normal and accident conditions, license conditions and so on. (orig.) [de

  5. Operational experience with the ATLAS Pixel Detector

    Ince, T; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost element of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.2% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  6. Operational experience of the ATLAS Pixel detector

    Hirschbuehl, D; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  7. Operational experience of the ATLAS Pixel Detector

    Marcisovsky, M; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  8. The LHC test string first operational experience

    Bézaguet, Alain-Arthur; Casas-Cubillos, J; Coull, L; Cruikshank, P; Dahlerup-Petersen, K; Faugeras, Paul E; Flemsæter, B; Guinaudeau, H; Hagedorn, Dietrich; Hilbert, B; Krainz, G; Kos, N; Lavielle, D; Lebrun, P; Leo, G; Mathewson, A G; Missiaen, D; Momal, F; Parma, Vittorio; Quesnel, Jean Pierre; Richter, D; Riddone, G; Rijllart, A; Rodríguez-Mateos, F; Rohmig, P; Saban, R I; Schmidt, R; Serio, L; Skiadelli, M; Suraci, A; Tavian, L; Walckiers, L; Wallén, E; Van Weelderen, R; Williams, L; McInturff, A

    1996-01-01

    CERN operates the first version of the LHC Test String which consists of one quadrupole and three 10-m twin aperture dipole magnets. An experimental programme aiming at the validation of the LHC systems started in February 1995. During this programme the string has been powered 100 times 35 of which at 12.4 kA or above. The experiments have yielded a number of results some of which, like quench recovery for cryogenics, have modified the design of subsystems of LHC. Others, like controlled helium leaks in the cold bore and quench propagation bewteen magnets, have given a better understanding on the evolution of the phenomena inside a string of superconducting magnets cooled at superfluid helium temperatures. Following the experimental programme, the string will be powered up and powered down in one hour cycles as a fatigue test of the structure thus simulating 20 years of operation of LHC.

  9. Small sodium valve design and operating experience

    McGough, C.B.

    1974-01-01

    The United States Liquid Metal Fast Breeder Reactor program (LMFBR) includes an extensive program devoted to the development of small sodium valves. This program is now focused on the development and production of valves for the Fast Flux Test Facility (FFTF) now under construction near Richland, Washington. Other AEC support facilities, such as various test loops located at the Liquid Metal Engineering Center (LMEC), Los Angeles, California, and at the Hanford Engineering Development Laboratory (HEDL), Richland, Washington, also have significant requirements for small sodium valves, and valves similar in design to the FFTF valves are being supplied to these AEC laboratories for use in their critical test installations. A principal motivation for these valve programs, beyond the immediate need to provide high-reliability valves for FFTF and the support facilities, is the necessity to develop small valve technology for the Clinch River Breeder Reactor Plant (CRBRP). FFTF small sodium valve design and development experience will be directly applied to the CRBRP program. Various test programs have been, and are being, conducted to verify the performance and integrity of the FFTF valves, and to uncover any potential problems so that they can be corrected before the valves are placed in service in FFTF. The principal small sodium valve designs being utilized in current U.S. programs, the test and operational experience obtained to date on them, problems uncovered, and future development and testing efforts being planned are reviewed. The standards and requirements to which the valves are being designed and fabricated, the valve designs in current use, valve operators, test and operating experience, and future valve development plans are summarized. (U.S.)

  10. Experience from operating germanium detectors in GERDA

    Palioselitis, Dimitrios; GERDA Collaboration

    2015-05-01

    Phase I of the Germanium Detector Array (GERDA) experiment, searching for the neutrinoless double beta (0νββ) decay of 76Ge, was completed in September 2013. The most competitive half-life lower limit for the 0νββ decay of 76Ge was set (T-0ν1/2 > 2.1 · 1025 yr at 90% C.L.). GERDA operates bare Ge diodes immersed in liquid argon. During Phase I, mainly refurbished semi-coaxial high purity Ge detectors from previous experiments were used. The experience gained with handling and operating bare Ge diodes in liquid argon, as well as the stability and performance of the detectors during GERDA Phase I are presented. Thirty additional new enriched BEGe-type detectors were produced and will be used in Phase II. A subgroup of these detectors has already been used successfully in GERDA Phase I. The present paper gives an overview of the production chain of the new germanium detectors, the steps taken to minimise the exposure to cosmic radiation during manufacturing, and the first results of characterisation measurements in vacuum cryostats.

  11. Experience from operating germanium detectors in GERDA

    Palioselitis, Dimitrios

    2015-01-01

    Phase I of the Germanium Detector Array (GERDA) experiment, searching for the neutrinoless double beta (0νββ) decay of 76 Ge, was completed in September 2013. The most competitive half-life lower limit for the 0νββ decay of 76 Ge was set (T- 0ν 1/2 > 2.1 · 10 25 yr at 90% C.L.). GERDA operates bare Ge diodes immersed in liquid argon. During Phase I, mainly refurbished semi-coaxial high purity Ge detectors from previous experiments were used. The experience gained with handling and operating bare Ge diodes in liquid argon, as well as the stability and performance of the detectors during GERDA Phase I are presented. Thirty additional new enriched BEGe-type detectors were produced and will be used in Phase II. A subgroup of these detectors has already been used successfully in GERDA Phase I. The present paper gives an overview of the production chain of the new germanium detectors, the steps taken to minimise the exposure to cosmic radiation during manufacturing, and the first results of characterisation measurements in vacuum cryostats. (paper)

  12. Operating experience with BWR nuclear power

    Bonsdorf, Magnus von.

    1986-01-01

    The two-unit nuclear power station in Olkiluoto on the western coast of Finland produces about 20 per cent of the electricity consumption of the country. The first unit, TVO-I was first connected to the national grid in September 1978 and TVO-II in February 1980. The original rated power output of each unit was 660 MWe, corresponding to the thermal power of 2000 MW from the reactor. Technical modifications allowed the power to be uprated by 8%. The operating statistics (load factors etc.) are given and the outage experience discussed. The radiological history shows very low radioactivity and dose levels have been maintained at the plant. (UK)

  13. Operational Experience with the ATLAS Pixel Detector

    Lantzsch, Kerstin; The ATLAS collaboration

    2016-01-01

    Run 2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). In addition the Pixel detector was refurbished with new service quarter panels to recover about 3% of defective modules lost during run 1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning, operation and performance of the 4-layer Pixel Detector will be presented.

  14. Simulator experiments: effects of NPP operator experience on performance

    Beare, A.N.; Gray, L.H.

    1984-01-01

    During the FY83 research, a simulator experiment was conducted at the control room simulator for a GE Boiling Water Reactor (BWR) NPP. The research subjects were licensed operators undergoing requalification training and shift technical advisors (STAs). This experiment was designed to investigate the effects of senior reactor operator (SRO) experience, operating crew augmentation with an STA and practice, as a crew, upon crew and individual operator performance, in response to anticipated plant transients. Sixteen two-man crews of licensed operators were employed in a 2 x 2 factorial design. The SROs leading the crews were split into high and low experience groups on the basis of their years of experience as an SRO. One half of the high- and low-SRO experience groups were assisted by an STA. The crews responded to four simulated plant casualties. A five-variable set of content-referenced performance measures was derived from task analyses of the procedurally correct responses to the four casualties. System parameters and control manipulations were recorded by the computer controlling the simulator. Data on communications and procedure use were obtained from analysis of videotapes of the exercises. Questionnaires were used to collect subject biographical information and data on subjective workload during each simulated casualty. For four of the five performance measures, no significant differences were found between groups led by high (25 to 114 months) and low (1 to 17 months as an SRO) experience SROs. However, crews led by low experience SROs tended to have significantly shorter task performance times than crews led by high experience SROs. The presence of the STA had no significant effect on overall team performance in responding to the four simulated casualties. The FY84 experiments are a partial replication and extension of the FY83 experiment, but with PWR operators and simulator

  15. Operating experience of steam generator test facility

    Sureshkumar, V.A.; Madhusoodhanan, G.; Noushad, I.B.; Ellappan, T.R.; Nashine, B.K.; Sylvia, J.I.; Rajan, K.K.; Kalyanasundaram, P.; Vaidyanathan, G.

    2006-01-01

    Steam Generator (SG) is the vital component of a Fast Reactor. It houses both water at high pressure and sodium at low pressure separated by a tube wall. Any damage to this barrier initiates sodium water reaction that could badly affect the plant availability. Steam Generator Test Facility (SGTF) has been set up in Indira Gandhi Centre for Atomic Research (IGCAR) to test sodium heated once through steam generator of 19 tubes similar to the PFBR SG dimension and operating conditions. The facility is also planned as a test bed to assess improved designs of the auxiliary equipments used in Fast Breeder Reactors (FBR). The maximum power of the facility is 5.7 MWt. This rating is arrived at based on techno economic consideration. This paper covers the performance of various equipments in the system such as Electro magnetic pumps, Centrifugal sodium pump, in-sodium hydrogen meters, immersion heaters, and instrumentation and control systems. Experience in the system operation, minor modifications, overall safety performance, and highlights of the experiments carried out etc. are also brought out. (author)

  16. Operating experience with gamma ray irradiators

    Fraser, F.M.; Ouwerkerk, T.

    1980-01-01

    The experience of Atomic Energy of Canada, Limited (AECL) with radioisotopes dates back to the mid-1940s when radium was marketed for medical purposes. Cobalt-60 came on the scene in 1949 and within a few years a thriving business in cancer teletherapy machines and research irradiators was developed. AECL's first full-scale cobalt-60 gamma ray sterilizer for medical products was installed in 1964. AECL now has over 50 plants and 30 million curies in service around the world. Sixteen years of design experience in cobalt-60 sources, radiation shielding, safety interlock systems, and source pass mechanisms have made gamma irradiators safe, reliable, and easy to operate. This proven technology is being applied in promising new fields such as sludge treatment and food preservation. Cesium-137 is expected to be extensively utilized as the gamma radiation source for these applications

  17. Operational Experience with the ATLAS Pixel Detector

    Djama, Fares; The ATLAS collaboration

    2017-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction imposed by the higher collision energy, pileup and luminosity that are being delivered. The ATLAS tracking performance relies critically on the Pixel Detector, therefore, in view of Run-2 of LHC, the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and an additional optical link per module was added to overcome in some layers the readout bandwidth limitation when LHC will exceed the nominal peak luminosity by almost a factor of 3. The key features and challenges met during the IBL project will be presented, as well as its operational experience and Pixel Detector performance in LHC.

  18. Operational Art and the ADF Experience

    2017-05-25

    Joint operations; 9. Distributed free maneuver; 10. The continuous front; 11. The empty battlefield; and 12. Commanders exercising operational vision...and purpose. The value of this analogy is that it demonstrates that operational art involves both sides of the issue, strategy and tactics...Objectives.” Speech , The International Conference on the Afghanistan Conflict and Australia’s Role, October 22-23, 2009, accessed December 06, 2016, http

  19. Experience in operation and maintenance of PWRs

    Broecker, H.; Schomer, E.

    1987-01-01

    At present there are 10 PWRs in operation, most of them built on turnkey basis by KWU. The availability of West German PWRs amounted to 84.7% on average for the period from 1982-86. The good operating results are attributable to the following: 1. Sophiticated design and layout of the plant with good accessibility to the primary system even during operation. 2. Reliable performance of plant and components as result of extensive quality assurance. 3. Well-organized and highly qualified operating personnel. 4. Inservice inspection and preventive maintenance. 5. Good information feedback system. (Liu)

  20. The tritium operations experience on TFTR

    Halle, A. von; Anderson, J.L.; Gentile, C.; Grisham, L.; Hosea, J.; Kamperschroer, J.; LaMarche, P.; Oldaker, M.; Nagy, A.; Raftopoulos, S.; Stevenson, T.

    1995-01-01

    The Tokamak Fusion Test Reactor (TFTR) tritium gas system is administratively limited to 5 grams of tritium and provides the feedstock gas for the neutral beam and torus injection systems. Tritium operations on TFTR began with leak checking of gas handling systems, qualification of the gas injection systems, and high power plasma operations using trace amounts of tritium in deuterium feedstock gas. Full tritium operation commenced with four highly diagnosed neutral beam pulses into a beamline calorimeter to verify planned tritium beam operating routines and to demonstrate the deuterium to tritium beam isotope exchange. Since that time, TFTR has successfully operated each of the twelve neutral beam ion sources in tritium during hundreds of tritium beam pulses and torus gas injections. This paper describes the TFTR tritium gas handling systems and TFTR tritium operations of the gas injection systems and the neutral beam ion sources. Tritium accounting and accountability is discussed, including tritium retention issues of the torus limiters and beam impinged surfaces of the beamline components. Also included is tritium beam velocity analysis that compares the neutral beam extracted ion species composition for deuterium and tritium and that determines the extent of beam isotope exchange on subsequent deuterium and tritium beam pulses. The required modifications to TFTR operating routines to meet the U.S. Department of Energy regulations for a low hazard nuclear facility and the problems encountered during initial tritium operations are described. (orig.)

  1. The tritium operations experience on TFTR

    von Halle, A.; Gentile, C.

    1994-01-01

    The Tokamak Fusion Test Reactor (TFTR) tritium gas system is administratively limited to 5 grains of tritium and provides the feedstock gas for the neutral beam and torus injection systems. Tritium operations on TFTR began with leak checking of gas handling systems, qualification of the gas injection systems, and high power plasma operations using using trace amounts of tritium in deuterium feedstock gas. Full tritium operation commenced with four highly diagnosed neutral beam pulses into a beamline calorimeter to verify planned tritium beam operating routines and to demonstrate the deuterium to tritium beam isotope exchange. Since that time, TFTR has successfully operated each of the twelve neutral beam ion sources in tritium during hundreds of tritium beam pulses and torus gas injections. This paper describes- the TFTR tritium gas handling systems and TFTR tritium operations of the gas injection systems and the neutral beam ion sources. Tritium accounting and accountability is discussed, including tritium retention issues of the torus limiters and beam impinged surfaces of the beamline components. Also included is tritium beam velocity analysis that compares the neutral beam extracted ion species composition for deuterium and tritium and that determines the extent of beam isotope exchange on subsequent deuterium and tritium beam pulses. The required modifications to TFTR operating routines to meet the US Department of Energy regulations for a low hazard nuclear facility and the problems encountered during initial tritium operations are described

  2. USA/FBR program status FFTF operations startup experience

    Moffitt, W.C.; Izatt, R.D.

    1981-06-01

    This paper gives highlights of the major Operations evaluations and operational results of the startup acceptance testing program and initiation of normal operating cycles for experiment irradiation in the FFTF. 33 figures

  3. Small sodium valve design and operating experience

    Abramson, R.; Elie, X.; Vercasson, M.; Nedelec, J.

    1974-01-01

    Conventionally, valves for sodium pipes smaller than 125 mm in diameter are called ''small sodium valves''. However, this limit should rather be considered as the lower limit o ''large sodium valves''. In fact, both the largest sizes of small valves and the smallest of large valves can be found in the range of 125-300 mm in diameter. Thus what is said about small valves also applies, for a few valve types, above the 125 mm limit. Sodium valves are described here in a general manner, with no manufacturing details except when necessary for understanding valve behavior. Operating experience is pointed out wherever possible. Finally, some information is given about ongoing or proposed development plans. (U.S.)

  4. Recent operational experiments at the LANSCE facility

    Rybarcyk, Lawrence J [Los Alamos National Laboratory

    2010-09-15

    The Los Alamos Neutron Science Center (LANSCE) consists of a pulsed 800-MeV room-temperature linear accelerator and an 800-MeV accumulator ring. It simultaneously provides H{sup +} and H{sup -} beams to several user facilities that have their own distinctive requirements, e.g. intensity, chopping pattern, duty factor, etc.. This multibeam operation presents challenges both from the standpoint of meeting the individual requirements but also achieving good overall performance for the integrated operation. Various aspects of more recent operations including the some of these challenges will be discussed.

  5. The Drop Tower Bremen -Experiment Operation

    Könemann, Thorben; von Kampen, Peter; Rath, Hans J.

    The idea behind the drop tower facility of the Center of Applied Space Technology and Micro-gravity (ZARM) in Bremen is to provide an inimitable technical opportunity of a daily access to short-term weightlessness on earth. In this way ZARM`s european unique ground-based microgravity laboratory displays an excellent economic alternative for research in space-related conditions at low costs comparable to orbital platforms. Many national and international ex-perimentalists motivated by these prospects decide to benefit from the high-quality and easy accessible microgravity environment only provided by the Drop Tower Bremen. Corresponding experiments in reduced gravity could open new perspectives of investigation methods and give scientists an impressive potential for a future technology and multidisciplinary applications on different research fields like Fundamental Physics, Astrophysics, Fluid Dynamics, Combus-tion, Material Science, Chemistry and Biology. Generally, realizing microgravity experiments at ZARM`s drop tower facility meet new requirements of the experimental hardware and may lead to some technical constraints in the setups. In any case the ZARM Drop Tower Operation and Service Company (ZARM FAB mbH) maintaining the drop tower facility is prepared to as-sist experimentalists by offering own air-conditioned laboratories, clean rooms, workshops and consulting engineers, as well as scientific personal. Furthermore, ZARM`s on-site apartment can be used for accommodations during the experiment campaigns. In terms of approaching drop tower experimenting, consulting of experimentalists is mandatory to successfully accomplish the pursued drop or catapult capsule experiment. For this purpose there will be a lot of expertise and help given by ZARM FAB mbH in strong cooperation to-gether with the experimentalists. However, in comparison to standard laboratory setups the drop or catapult capsule setup seems to be completely different at first view. While defining a

  6. Operating experience at Scottish Nuclear's power stations

    Blackburn, P.

    1991-01-01

    A brief history is presented of the design and operation of the four Scottish nuclear power stations currently run by Scottish Nuclear, namely Hunterston 'A' and 'B' and the Torness reactors. A design flaw in the Magnox reactor at Hunterston 'A' led to it being operated at lower than optimal temperature and hence producing less power. For Hunterston 'B' reactor the Advanced Gas Cooled design prototype was used. Operating setbacks and successes are noted. The design chosen for Torness embraced all the good points of Hunterston 'B' but sought to eliminate its faults. After 26 years of successful operation Hunterston 'A' is now being decommissioned, while the other three stations continue to generate electricity successfully. (UK)

  7. Phobos L1 Operational Tether Experiment (PHLOTE)

    National Aeronautics and Space Administration — A sensor package that “floats” just above the surface of Phobos, suspended by a tether from a small spacecraft operating at the Mars/Phobos Lagrange 1 (L1) Point...

  8. Operating experience of Fugen Nuclear Power Station

    Ohteru, Shigeru; Kaneko, Jun; Kawahara, Toshio; Matsumoto, Mitsuo

    1987-01-01

    The prototype ATR 'Fugen' developed as one of the national project has verified the performance and reliability of the advanced thermal reactor system through the operation for about eight years since 1979, and the elucidation of the characteristics in plutonium utilization and the development and verification of the tuilizing techniques have been advanced. Besides, the operational results and the achievement of the technical development are successively reflected to the design of a demonstration reactor. In this paper, the outline of Fugan and the operational results are reported. The ATR Fugen Power Station is that of the prototype reactor of heavy water moderated, boiling light water cooled, pressure tube type, having the electric output of 165 MW. It started the full scale operation on March 20, 1979, and as of January, 1987, the total generated electric power reached about 7 billion kWh, the time of power generation was about 43,000 h, and the average capacity factor was 60.6 %. Plutonium utilization techniques, the flow characteristics and the dynamic plant characteristics of a pressure tube type reactor, the operational characteristics of a heavy water system and the techniques of handling heavy water containing tritium, and the operational reliability and maintainability of the machinery and equipment installed have been studied. (Kako, I.)

  9. Synthetic vision systems: operational considerations simulation experiment

    Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Glaab, Louis J.

    2007-04-01

    Synthetic vision is a computer-generated image of the external scene topography that is generated from aircraft attitude, high-precision navigation information, and data of the terrain, obstacles, cultural features, and other required flight information. A synthetic vision system (SVS) enhances this basic functionality with real-time integrity to ensure the validity of the databases, perform obstacle detection and independent navigation accuracy verification, and provide traffic surveillance. Over the last five years, NASA and its industry partners have developed and deployed SVS technologies for commercial, business, and general aviation aircraft which have been shown to provide significant improvements in terrain awareness and reductions in the potential for Controlled-Flight-Into-Terrain incidents / accidents compared to current generation cockpit technologies. It has been hypothesized that SVS displays can greatly improve the safety and operational flexibility of flight in Instrument Meteorological Conditions (IMC) to a level comparable to clear-day Visual Meteorological Conditions (VMC), regardless of actual weather conditions or time of day. An experiment was conducted to evaluate SVS and SVS-related technologies as well as the influence of where the information is provided to the pilot (e.g., on a Head-Up or Head-Down Display) for consideration in defining landing minima based upon aircraft and airport equipage. The "operational considerations" evaluated under this effort included reduced visibility, decision altitudes, and airport equipage requirements, such as approach lighting systems, for SVS-equipped aircraft. Subjective results from the present study suggest that synthetic vision imagery on both head-up and head-down displays may offer benefits in situation awareness; workload; and approach and landing performance in the visibility levels, approach lighting systems, and decision altitudes tested.

  10. Synthetic Vision Systems - Operational Considerations Simulation Experiment

    Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Glaab, Louis J.

    2007-01-01

    Synthetic vision is a computer-generated image of the external scene topography that is generated from aircraft attitude, high-precision navigation information, and data of the terrain, obstacles, cultural features, and other required flight information. A synthetic vision system (SVS) enhances this basic functionality with real-time integrity to ensure the validity of the databases, perform obstacle detection and independent navigation accuracy verification, and provide traffic surveillance. Over the last five years, NASA and its industry partners have developed and deployed SVS technologies for commercial, business, and general aviation aircraft which have been shown to provide significant improvements in terrain awareness and reductions in the potential for Controlled-Flight-Into-Terrain incidents/accidents compared to current generation cockpit technologies. It has been hypothesized that SVS displays can greatly improve the safety and operational flexibility of flight in Instrument Meteorological Conditions (IMC) to a level comparable to clear-day Visual Meteorological Conditions (VMC), regardless of actual weather conditions or time of day. An experiment was conducted to evaluate SVS and SVS-related technologies as well as the influence of where the information is provided to the pilot (e.g., on a Head-Up or Head-Down Display) for consideration in defining landing minima based upon aircraft and airport equipage. The "operational considerations" evaluated under this effort included reduced visibility, decision altitudes, and airport equipage requirements, such as approach lighting systems, for SVS-equipped aircraft. Subjective results from the present study suggest that synthetic vision imagery on both head-up and head-down displays may offer benefits in situation awareness; workload; and approach and landing performance in the visibility levels, approach lighting systems, and decision altitudes tested.

  11. EBR-II: summary of operating experience

    Perry, W.H.; Leman, J.D.; Lentz, G.L.; Longua, K.J.; Olson, W.H.; Shields, J.A.; Wolz, G.C.

    1978-01-01

    Experimental Breeder Reactor II (EBR-II) is an unmoderated, sodium-cooled reactor with a design power of 62.5 MWt. The primary cooling system is a submerged-pool type. The early operation of the reactor successfully demonstrated the feasibility of a sodium-cooled fast breeder reactor operating as an integrated reactor, power plant, and fuel-processing facility. In 1967, the role of EBR-II was reoriented from a demonstration plant to an irradiation facility. Many changes have been made and are continuing to be made to increase the usefulness of EBR-II for irradiation and safety tests. A review of EBR-II's operating history reveals a plant that has demonstrated high availability, stable and safe operating characteristics, and excellent performance of sodium components. Levels of radiation exposure to the operating and maintenance workers have been low; and fission-gas releases to the atmosphere have been minimal. Driver-fuel performance has been excellent. The repairability of radioactive sodium components has been successfully demonstrated a number of times. Recent highlights include installation and successful operation of (1) the hydrogen-meter leak detectors for the steam generators, (2) the cover-gas-cleanup system and (3) the cesium trap in the primary sodium. Irradiations now being conducted in EBR-II include the run-beyond-cladding breach fuel tests for mixed-oxide and carbide elements. Studies are in progress to determine EBR-II's capability for conducting important ''operational safety'' tests. These tests would extend the need and usefulness of EBR-II into the 1980's

  12. Evaluation of German and international operating experience

    Stueck, Reinhard; Verstegen, Claus

    2014-01-01

    The systematic analysis of safety-relevant events in nuclear power plants and their causes is a key driver for the further development of nuclear safety. The findings obtained from the evaluation of operating experience in this respect form the basis for both technical and organisational improvements in the plants as well as for adaptations of technical rules and standards. In its role as Technical Safety Organisation advising the German federal government, Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) has been concerned with the detection and analysis of failure mechanisms that underlie events in nuclear power plants at home and abroad since its foundation in 1977. This article provides an overview of the different objectives which are pursued in this context by order of or funded by the Federal Environment Ministry. Here, the focus is on the evaluation of reportable events for the preparation of so-called Information Notices and generic reports as well as for the acquisition of data that can be used for in-depth probabilistic analyses.

  13. Proposed Reactor Operating Experience Feedback System Development

    Ahn, Seung Hoon; Kim, Min Chul; Huh, Chang Wook; Lee, Durk Hun; Bae, Koo Hyun

    2006-01-01

    Most events occurring in nuclear power plants are not individually significant, and prevented from progressing to accident conditions by a series of barriers against core damage and radioactive releases. Significant events, if occur, are almost always a breach of these multiple barriers. As illustrated in the 'Swiss cheese' model, the individual layers of defense or 'cheese slices' have weakness or 'holes.' These weaknesses are inconstant, i.e., the holes are open or close at random. When by chance all the holes are aligned, a hazard causes the significant event of concern. Elements of low significant events, inattention to detail, time or economic pressure, uncorrected poor practices/habits, marginal maintenance and equipment care, etc., make holes in the layers of defense; some elements may make more holes in different layers, incurring more chances to be aligned. An effective reduction of the holes, therefore, is gained through better knowledge or awareness of increasing trends of the event elements, followed by appropriate actions. According to the Swiss cheese metaphor, attention to the Operating Experience (OE) feedback system, as opposed to the individual and to randomness, is drawn from a viewpoint of reactor safety

  14. Five years of operating experience with Phenix

    Conte, F.

    1980-01-01

    The construction of Phenix began at the end of 1968; the unit first went critical on August 31 st, 1973, and it was first connected to the grid of Electricite de France on 31st December 1973. It started operating industrially on July 14th, 1974. The balance sheet after five years of operations is as follows: Gross thermal capacity: 590 MW; Grosss electric capacity: 264 MW; Gross capacity factor of the power station: 45%; Gross electrical power produced by 30th september 1979: more than six billion kWh. In 1976 and 1977 the operation of the plant was affected by modifications made to the intermediate heat exchangers following leaks discovered in October 1976. Since 1976 the plants has been working at full capacity and the availability rate during the period July 1978 - July 1979 was more than 80% [fr

  15. Vapour trap development and operational experience

    Jansing, W.; Kirchner, G.; Menck, J.

    1977-01-01

    Sodium aerosols have the unpleasant characteristic that they deposit at places with low temperature level. This effect can be utilized when sodium aerosols are to be trapped at places which are determined beforehand. Thus vapour traps were developed which can filter sodium vapour from the cover gas. By this means the necessity was eliminated to heat all gas lines and gas systems with trace heaters just as all sodium lines are heated. It was of special interest for the INTERATOM to develop vapour traps which must not be changed or cleaned after a certain limited operating period. The vapour traps were supposed to enable maintenance free operation, i.e. they were to operate 'self cleaning'

  16. Commonwealth Edison operating experience: the people factor

    Soth, L.

    1983-01-01

    Since 1955, Commonwealth Edison's nuclear commitment has evolved into three operating stations, another in startup, and two more under construction. Paralleling this evolution has been the investment in the personnel resources to operate, maintain, and manage these facilities. The personnel resource, its training and development, is the foundation for safe operation at any nuclear plant - the people factor. The personnel requirement at Edison has expanded and evolved with each station to meet ever increasing regulatory requirements. An extensive training organization has been developed to emphasize the importance of the man side of the human factors man/machine interface. Personnel errors are investigated to identify and correct the root causes, and outstanding personnel performance is recognized by the Company

  17. Operating experience with the DRAGON High Temperature Reactor experiment

    Simon, R.A.; Capp, P.D.

    2002-01-01

    The Dragon Reactor Experiment in Winfrith/UK was a materials test facility for a number of HTR projects pursued in the sixties and seventies of the last century. It was built and managed as an OECD/NEA international joint undertaking. The reactor operated successfully between 1964 and 1975 to satisfy the growing demand for irradiation testing of fuels and fuel elements as well as for technological tests of components and materials. The paper describes the reactor's main experimental features and presents results of 11 years of reactor operation relevant for future HTRs. (author)

  18. Operating experience feedback report - Air systems problems

    Ornstein, H.L.

    1987-12-01

    This report highlights significant operating events involving observed or potential failures of safety-related systems in U.S. plants that resulted from degraded or malfunctioning non-safety grade air systems. Based upon the evaluation of these events, the Office for Analysis and Evaluation of Operational Data (AEOD) concludes that the issue of air systems problems is an important one which requires additional NRC and industry attention. This report also provides AEOD's recommendations for corrective actions to deal with the issue. (author)

  19. Operating experience with KRAFTWERK UNION cementation line

    Podmaka, L.; Tomik, L.

    1988-01-01

    A facility is described designed for fixation in a cement matrix of the radioactive concentrate produced by thickening waste water from the Bohunice nuclear power plant. The cementation line output is 0.6 m 3 concentrate/h. The concentrate is put in 200 l drums. The individual operating units, cement management, air conditioning, dosimetric monitoring and the building part are described. The requirements for the operators and the assessment of the quality of raw materials and the product are discussed. (M.D.). 3 figs., 4 refs

  20. Operational Experience with the CMS Pixel Detector

    INSPIRE-00205212

    2015-05-15

    In the first LHC running period the CMS-pixel detector had to face various operational challenges and had to adapt to the rapidly changing beam conditions. In order to maximize the physics potential and the quality of the data, online and offline calibrations were performed on a regular basis. The detector performed excellently with an average hit efficiency above 99\\% for all layers and disks. In this contribution the operational challenges of the silicon pixel detector in the first LHC run and the current long shutdown are summarized and the expectations for 2015 are discussed.

  1. Operating experience review for the AP1000 plant

    Chaney, T. E.; Lipner, M. H.

    2006-01-01

    Westinghouse is performing an update to the Operating Experience Review (OER) Report for the AP1000 project to account for operating experience since December 1996. Significant Operating Experience Reports, Significant Event Reports, Significant Event Notifications, Operations and Maintenance Reminders, Topical Reports, Event Analysis Reports and Licensee Event Reports were researched for pertinent input to the update. As a part of the OER, Westinghouse has also conducted operator interviews and observations during simulated plant operations and after operating events. The main purpose of the OER is to identify Human Factors Engineering (HFE) related safety issues from existing operating plant experience and to ensure that these issues are addressed in the new design. The issues and lessons learned regarding operating experience provide a basis for improving the plant design. (authors)

  2. Operating experience with existing light sources

    Barton, M.Q.

    1985-01-01

    It is instructive to consider what an explosive growth there has been in the development of light sources using synchrotron radiation. This is well illustrated by the list of facilities given in Table I. In many cases, synchrotron light facilities have been obtained by tacking on parasitic beam lines to rings that were built for high energy physics. Of the twenty-three facilities in this table, however, eleven were built explicitely for this synchrotron radiation. Another seven have by now been converted for use as dedicated facilities leaving only five that share time with high energy physics. These five parasitically operated facilities are still among our best sources of hard x-rays, however, and their importance to the fields of science where these x-rays are needed must be emphasized. While the number of facilities in this table is impressive, it is even more impressive to add up the total number of user beam lines. Most of these rings are absolutely surrounded by beam lines and finding real estate on the experimental floor of one of these facilities for adding a new experiment looks about as practical as adding a farm in the middle of Manhattan. Nonetheless, the managers of these rings seem to have an attitude of ''always room for one more'' and new experimental beam lines do appear. This situation is necessary because the demand for beam time has exploded at an even faster rate than the development of the facilities. The field is not only growing, it can be expected to continue to grow for some time. Some of the explicit plans for future development will be discussed in the companion paper by Lee Teng

  3. 14th Biennial conference on reactor operating experience plant operations: The human element

    Anon.

    1989-01-01

    Separate abstracts were prepared for the papers presented in the following areas of interest: enhancing operator performance; structured approaches to maintenance standards and reliability-centered maintenance; human issues in plant operations and management; test, research, and training reactor utilization; methods and applications of root-cause analysis; emergency operating procedure enhancement programs; test, research, and training reactor upgrades; valve maintenance and diagnostics; recent operating experiences; and current maintenance issues

  4. Treatment of operational experience of nuclear power plants in WANO

    Ibanez, M.

    2013-01-01

    The article describes the activities associated to the Operating Experience Programme of the World Association of Nuclear Operators. The programme manages the event reports submitted by the nuclear power plants to the WANO database for the preparation by the Operating Experience Central Team of some documents like the significant Operating Experience Reports and Significant Event Reports that help the stations to avoid similar events. (Author)

  5. Operational experience with the CERN hadron linacs

    Charmot, H.; Dutriat, C.; Hill, C.E.; Langbein, K.; Lombardi, A.M.; O'Neil, M.; Tanke, E.; Vretenar, M.

    1996-01-01

    The present CERN proton linac (Linac2) was commissioned in 1978 and since that date has been the primary source of protons to the CERN accelerator complex. During the past 18 years, the machine has had a very good reliability record in spite of the demands made upon it. Modifications have been made with the view of maintaining this reliability with reduced resources and new requirements from the users. Further demands will be made in the future for LHC operation. In 1994, a new linac for heavy ion production was put into service replacing the original CERN proton linac. As this machine was built within an international collaboration, operation had to take into account the novelty of the techniques used and the variety of equipment supplied by outside collaborators. Even so, the new machine has also had very good reliability. (author)

  6. Overview - Defense Waste Processing Facility Operating Experience

    Norton, M.R.

    2002-01-01

    The Savannah River Site's Defense Waste Processing Facility (DWPF) near Aiken, SC is the world's largest radioactive waste vitrification facility. Radioactive operations began in March 1996 and over 1,000 canisters have been produced. This paper presents an overview of the DWPF process and a summary of recent facility operations and process improvements. These process improvements include efforts to extend the life of the DWPF melter, projects to increase facility throughput, initiatives to reduce the quantity of wastewater generated, improved remote decontamination capabilities, and improvements to remote canyon equipment to extend equipment life span. This paper also includes a review of a melt rate improvement program conducted by Savannah River Technology Center personnel. This program involved identifying the factors that impacted melt rate, conducting small scale testing of proposed process changes and developing a cost effective implementation plan

  7. Operating experience from Swedish nuclear power plants

    NONE

    1998-06-01

    During 1997 the PWRs in Ringhals performed extremely well (capability factors 85-90%), the unit Ringhals 2 reached the best capability factor since commercial operation started in 1976. The BWRs made an average 76% capability, which is somewhat less than in 1996. The slightly reduced capability derives from ongoing modernization projects at several units. At the youngest plants, Forsmark 3 and Oskarshamn 3, capability and utilization were very high. Events and data for 1997 are given for each reactor, together with operational statistics for the years 1990-1997. A number of safety-related events are reported, which occurred st the Swedish plants during 1997. These events are classified as level 1 or higher on the international nuclear event scale (INES).

  8. Three years operational experience with biodiesel

    Murphy, J.

    2008-01-01

    TSI Terminal Systems Inc. is the largest container terminal operator in Canada, and has an annual payroll exceeding $150 million. The company started a biodiesel test program with the Canadian Bioenergy Corporation in order to assess the emission reduction impacts of using biodiesel. The pilot was tested with 6 different pieces of equipment used at the terminal over an initial period of 3 weeks. Emissions testing was then conducted for different biodiesel blend levels and compared with baseline data in relation to particulate matter, total hydrocarbons, carbon monoxide (CO), carbon dioxide (CO 2 ), and nitrous oxides (NO x ). Results of the tests confirmed that the biodiesel blends significantly reduced emissions at the terminal and confirmed the operability of biodiesel. Overall emissions were reduced by 30 per cent. The fuel is now being used in all the company's equipment. The use of the biodiesel has not resulted in any engine failures or power losses. tabs., figs

  9. Operating experience from Swedish nuclear power plants

    1998-01-01

    During 1997 the PWRs in Ringhals performed extremely well (capability factors 85-90%), the unit Ringhals 2 reached the best capability factor since commercial operation started in 1976. The BWRs made an average 76% capability, which is somewhat less than in 1996. The slightly reduced capability derives from ongoing modernization projects at several units. At the youngest plants, Forsmark 3 and Oskarshamn 3, capability and utilization were very high. Events and data for 1997 are given for each reactor, together with operational statistics for the years 1990-1997. A number of safety-related events are reported, which occurred st the Swedish plants during 1997. These events are classified as level 1 or higher on the international nuclear event scale (INES)

  10. FFTF operating experience, 1982-1984

    Waldo, J.B.; Franz, G.R.; Loika, E.F.; Krupar, J.J.

    1984-01-01

    The Fast Flux Test Facility (FFTF) is a 400 Mwt sodium-cooled fast reactor operating at the Hanford Engineering Development Laboratory, Richland, Washington, to conduct fuels and materials testing in support of the US Liquid Metal Fast Breeder Reactor (LMFBR) program. Startup and initial power testing included a comprehensive series of nonnuclear and nuclear tests to verify the thermal, hydraulic, and neutronic characteristics of the plant. A specially designed series of natural circulation tests were then performed to demonstrate the inherent safety features of the plant. Early in 1982, the FFTF began its first 100-day irradiation cycle. Since that time the plant has operated very well, achieving a cycle capacity factor of 94% in the most recent irradiation cycle. Seventy-five specific test assemblies and 25,000 individual fuel pins have been irradiated, some in excess of 80 MWd/Kg

  11. Operational experience with the Fermilab Linac

    Allen, L.J.; Lennox, A.J.; Schmidt, C.W.

    1992-01-01

    The Fermilab 200-MeV Linac has been in operation for nearly 22 years as a proton injector to the Booster synchrotron. It presently accelerates H - ions to 200 MeV for charge-exchange injection into the Booster and to 66 MeV for the production of neutrons at the Neutron Therapy Facility (NTF). The beam intensity is typically 35 mA with pulse widths of 30 μsec for the Booster for high energy physics and 57 μsec for NTF at a maximum of 15 pulses per sec. During a typical physics run of nine to twelve months, beam is available for greater than 98% of the scheduled time. The Linac history, operation, tuning, stability and reliability will be discussed. (Author) 15 refs., 2 tabs

  12. Operational experience with propulsion nuclear plants

    Polunichev, V.

    2000-01-01

    Russia possesses a powerful icebreaker transport fleet which offers a solution for important socio-economic tasks of the country's northern regions by maintaining a year-round navigation along the Arctic Sea route. The total operating record of the propulsion nuclear reactors till now exceeds 150 reactor-years, their main equipment items operating life amounted to 120,000 h. Progressive design-constructional solutions being perfected continuously during 40 years of nuclear-powered ships creation in Russia and well proven technology of all components used in the marine nuclear reactors give grounds to recommend marine Nuclear Steam Supply Systems (NSSSs) of KLT-40 type as energy sources for heat and power cogeneration plants and sea water desalination complexes, particularly as floating installations. Co-generation stations are considered for deployment in the extreme north of Russia. Nuclear floating desalination complexes can be used for drinkable water production in coastal regions of Northern Africa, the Near East, India etc. (author)

  13. Operational experience in the United Kingdom

    Gronow, W.S.

    1977-01-01

    In the UK there are 26 Magnox reactors and 4 AGRs operating on 11 licensed sites; a further 6 AGRs are under construction on 2 additional and one of the existing sites. The arrangements by which the Nuclear Installations Inspectorate, on behalf of the Health and Safety Executive, carries out its regulatory functions at operating nuclear power plants are described. The range of activities undertaken is described with special reference being made to the biennial shutdowns for approved maintenance and inspections which are required by conditions attached to the site licence. The other means by which the continuing safety of these power reactors is assured are explained and include the relationship with the licensee's own Nuclear Safety Committee, approved arrangements for modifications to plant systems or components which have importance for safety and long term reviews of safety aspects. (author)

  14. Weapons Experiments Division Explosives Operations Overview

    Laintz, Kenneth E. [Los Alamos National Laboratory

    2012-06-19

    Presentation covers WX Division programmatic operations with a focus on JOWOG-9 interests. A brief look at DARHT is followed by a high level overview of explosives research activities currently being conducted within in the experimental groups of WX-Division. Presentation covers more emphasis of activities and facilities at TA-9 as these efforts have been more traditionally aligned with ongoing collaborative explosive exchanges covered under JOWOG-9.

  15. Operational experience at Fort St. Vrain

    Bramblett, G.C.; Fisher, C.R.; Swart, F.E.

    1981-01-01

    The Fort St. Vrain (FSV) station, a 330-MW(e) single reheat steam cycle powered by a high-temperature gas-cooled reactor (HTGR), is the first HTGR to enter commercial operation. Designed and built by General Atomic Company (GA), the plant is owned and operated by Public Service Company of Colorado (PSC). Many unique design features have been incorporated into this reactor system, including high-pressure helium as the primary system coolant, a graphite-moderated prismatic block core design, fission-product-containing carbide coatings on both fissile and fertile fuel particles, steam-driven helium circulators turning on water bearings, and once-through steam generators. All of these systems are contained in a prestressed concrete reactor vessel (PCRV). Extensive testing has been conducted during the rise to power following first criticality early in 1974 to verify system design performance. During this period, the plant has operated at power levels up to 70% and produced over one billion kilowatt hours of electricity. In 1979, the first refueling was conducted in conjunction with an extensive in-core inspection, the addition of in-core instrumentation, and a planned removal of a circulator for inspection. Later in the year, a scheduled shutdown was undertaken for surveillance tests, insertion of core region constraint devices (RCDs), and other maintenance. Fort St. Vrain has encountered problems of the type that would be expected in a first-of-a-kind system. The plant is currently restricted to 70% of design power by the Nuclear Regulatory Commission (NRC) pending resolution of the core region gas outlet temperature fluctuation problem. Even so, the basic performance of the HTGR concept and all of the unique design features have been successfully demonstrated. The system has been characterized by low personnel radiation exposures, operational flexibility, and long time afforded for status evaluation and response. (author)

  16. Fort St. Vrain circulator operating experience

    Brey, H. L.

    1988-08-15

    Fort St. Vrain, on the system of Public Service Company of Colorado, is the only high-temperature gas-cooled power reactor in the United States. Four helium circulators are utilized in this plant to transfer heat from the reactor to the steam generators. These unique machines have a single stage axial flow helium compressor driven by a single stage steam turbine. A single stage water driven (pelton wheel) turbine is the back-up drive utilizing either feed water, condensate, or fire water as the driving fluid. Developmental testing of the circulators was accomplished prior to installation into Fort St. Vrain. A combined machine operating history of approximately 250,000 hours has shown these machines to be of conservative design and proven mechanical integrity. However, many problems have been encountered in operating the complex auxiliaries which are necessary for successful circulator and plant operation. It has been 15 years since initial installation of the circulators occurred at Fort St. Vrain. During this time, a number of significant issues had to be resolved dealing specifically with machine performance. These events include cavitation damage of the pelton wheels during the initial plant hot functional testing, cracks in the water turbine buckets and cervic coupling, static shutdown seal bellows failure, and, most recently, degradation of components within the steam drive assembly. Unreliable operation particularly with the circulator auxiliaries has been a focus of attention by Public Service Company of Colorado. Actions to replace or significantly modify the existing circulators and their auxiliaries are currently awaiting decisions concerning the long-term future of the Fort St. Vrain plant. (author). 10 refs, 7 figs, 2 tabs.

  17. Fort St. Vrain circulator operating experience

    Brey, H.L.

    1988-01-01

    Fort St. Vrain, on the system of Public Service Company of Colorado, is the only high-temperature gas-cooled power reactor in the United States. Four helium circulators are utilized in this plant to transfer heat from the reactor to the steam generators. These unique machines have a single stage axial flow helium compressor driven by a single stage steam turbine. A single stage water driven (pelton wheel) turbine is the back-up drive utilizing either feed water, condensate, or fire water as the driving fluid. Developmental testing of the circulators was accomplished prior to installation into Fort St. Vrain. A combined machine operating history of approximately 250,000 hours has shown these machines to be of conservative design and proven mechanical integrity. However, many problems have been encountered in operating the complex auxiliaries which are necessary for successful circulator and plant operation. It has been 15 years since initial installation of the circulators occurred at Fort St. Vrain. During this time, a number of significant issues had to be resolved dealing specifically with machine performance. These events include cavitation damage of the pelton wheels during the initial plant hot functional testing, cracks in the water turbine buckets and cervic coupling, static shutdown seal bellows failure, and, most recently, degradation of components within the steam drive assembly. Unreliable operation particularly with the circulator auxiliaries has been a focus of attention by Public Service Company of Colorado. Actions to replace or significantly modify the existing circulators and their auxiliaries are currently awaiting decisions concerning the long-term future of the Fort St. Vrain plant. (author). 10 refs, 7 figs, 2 tabs

  18. Operational experience with the CEBAF control system

    Hovater, C.; Chowdhary, M.; Karn, J.; Tiefenback, M.; Zeijts, J. van; Watson, W.

    1996-01-01

    The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) successfully began its experimental nuclear physics program in November of 1995 and has since surpassed predicted machine availability. Part of this success can be attributed to using the EPICS (Experimental Physics and Industrial Control System) control system toolkit. The CEBAF control system is one of the largest accelerator control system now operating. It controls approximately 338 SRF cavities, 2,300 magnets, 500 beam position monitors and other accelerator devices, such as gun hardware and other beam monitoring devices. All told, the system must be able to access over 125,000 database records. The system has been well received by both operators and the hardware designers. The EPICS utilities have made the task of troubleshooting systems easier. The graphical and test-based creation tools have allowed operators to custom build control screens. In addition, the ability to integrate EPICS with other software packages, such as Tcl/Tk, has allowed physicists to quickly prototype high-level application programs, and to provide GUI front ends for command line driven tools. Specific examples of the control system applications are presented in the areas of energy and orbit control, cavity tuning and accelerator tune up diagnostics

  19. Operational experience at Fort St. Vrain

    Bramblett, G. C.; Fisher, C. R.; Swart, F. E. [General Atomic Co., San Diego, CA (USA)

    1981-01-15

    The Fort St. Vrain (FSV) station, a 330-MW(e) single reheat steam cycle powered by a high-temperature gas-cooled reactor (HTGR), is the first HTGR to enter commercial operation. Designed and built by General Atomic Company (GA), the plant is owned and operated by Public Service Company of Colorado (PSC). Many unique design features have been incorporated into this reactor system, including high-pressure helium as the primary system coolant, a graphite-moderated prismatic block core design, fission-product-containing carbide coatings on both fissile and fertile fuel particles, steam-driven helium circulators turning on water bearings, and once-through steam generators. All of these systems are contained in a prestressed concrete reactor vessel (PCRV). Extensive testing has been conducted during the rise to power following first criticality early in 1974 to verify system design performance. During this period, the plant has operated at power levels up to 70% and produced over one billion kilowatt hours of electricity. In 1979, the first refueling was conducted in conjunction with an extensive in-core inspection, the addition of in-core instrumentation, and a planned removal of a circulator for inspection.

  20. Experience in startup and operation of fast flux facility

    Moffitt, W.C.

    1980-01-01

    The testing program was structured to perform all testing under formal testing procedures with a test engineer as the test director and the plant operators operating the systems and equipment. This provided excellent training and experience for the operators in preparation for eventual reactor operation. Operations preparations for the testing and operation activities has consisted of academic training, formal on-the-job training including systems operation and examinations by persons with an expert knowledge on that portion of the plant, training at EBR-II and the High Temperature Sodium Facility for selected senior operators, operating procedure preparation, training on an FFTF Control Room operator training simulator, and formal written, oral and operating examinations

  1. Operational experiences of INES in Japan

    1997-01-01

    Japan has introduced IAEA's INES in August, 1992. As of September, 1997, the total number of domestic nuclear events which have evaluated by using the INES system has amounted 119. In Japan, when a nuclear event occurs at a nuclear power plant, a provisional evaluation is performed immediately by Nuclear Power Operation Administration Office, MITI. The final evaluation of events is implemented a few months after event occurrence by the Evaluation Committee on Incidents and Failures of Nuclear Power Plant which holds a neutral position. The results of the evaluation are transmitted to IAEA according to the INES reporting criteria

  2. Operating experiences at the Finnish TRIGA reactor

    Salmenhaara, Seppo

    1988-01-01

    The Finnish TRIGA reactor has been in operation since March 1962. There are still 57 original Al-clad fuel elements in the core. So far we have had only two fuel cladding failures in 1981 and 1988. The first one was an Al-clad element and the second one a SS-clad. The low rate of fuel cladding failures has made it possible to use continuously also the Al-clad fuel elements. Although some conventional irradiations of certain type have been repeated successfully tens of times, new and unexpected incidents can still take place. As an example an event of a leaking irradiation capsule is described

  3. Operating experience with the ALS linac

    Selph, F.; Massoletti, D.

    1991-05-01

    The linac injector for the Advanced Light Source (ALS) at LBL was recently put into operation. Energy is 50 MeV, frequency 3 GHz. The electron gun delivers up to 6nC in a 3.0-ns bunch at 120 kV. A train of bunches is injected into a 1-Hz booster and accelerated to 1.5 GHz for storage ring injection. A magnetic analysis system is used for optimizing the linac. Measured beam properties from the gun and after acceleration in the linac are described. 9 refs., 3 figs

  4. Operating experience with 600 MW steam turbosets

    Tinapp, J.

    1978-01-01

    The turbosets of the 600 MW line are machines with 4 casing, with a single-flow high-pressure turbine, a double-flow MD part, and two double-flow low-pressure turbines. The common design of all BBC turbosets of this size is explained, with a few remarks on the typical constructional features of BBC technology. The plant has a mean availability of 96% and a mean forced shutdown rate of 1.2%. A table gives a survey of the start-up procedure and the operating results so far. (GL) [de

  5. Evaluation of operating experience with safety values

    Bung, W.; Hoemke, P.; Oberender, W.; Paul, H.; Rueter, W.

    1985-01-01

    This report describes statistical investigations of 2076 functional tests carried out on power operated safety valves in conventional power plants in 1972 until 1983 with special regard to Common Mode-Failures. The results clearly show that Common Mode-Failures play an important part of non-availability for the controlled safety valves, especially in the control system. The 'Deutsche Risikostudie' does not consider any Common Mode-Failures of the primary safety valves. However there is no significant increase of the risk resulted by the primary safety valves in the 'Referenzanlage' if the calculated Common Mode-Failures probabilities are considered. (orig.) [de

  6. MOX use in PWRs. EDF operation experience

    Provost, Jean-Luc; Debes, Michel

    2011-01-01

    From the origin, EDF back-end fuel cycle strategy has focused on 'closing the fuel cycle', in other words integrating fuel reprocessing, with vitrification of high level waste concentrated within small volumes, and the recycling of valuable materials. The implementation of this policy was marked in 1987 by the first loading of sixteen MOX. By December 2010, 20 reactors have been loaded with 1750 tHM of MOX. EDF current strategy is to match the reprocessing program with MOX manufacturing capacity to limit the quantity of separated plutonium. This is routinely called the 'flow ad-equation' strategy. Currently, the MOX Parity core management achieves balance of MOX and UOX performance with a significant increase of the MOX discharge burn-up. Globally, the behavior under irradiation of MOX fuel assemblies has been satisfactory. So far, from the beginning of MOX use in EDF PWRs, only 6 MOX FAs with rod leakage have been identified, which gives a very satisfactory level of reliability. The industrial maturity of MOX fuel, with increased performances, allows the improvement of nuclear KWh competitiveness and of the plant operation performance, while maintaining in operation the same safety level, without significant impact on environment and radiological protection. (author)

  7. Operational experience acquired in radioactive waste compaction

    Bauer, S.; Mohr, P.; Hempelmann, W.

    1993-01-01

    The low-level radioactive waste scrapping facility in the KfK decontamination division was commissioned in 1983. Non-combustible residues and removed system components of low activity, but which are to be handled and disposed of as radioactive waste are in drums, casks or containers delivered to the facility. The waste usually undergoes pretreatment in a crusher, with the volume being definitively reduced at a pressure of 690 bar in the high-pressure compactor. In 1990, the overhead-crane was refurbished for remote control handling in the scrapping caisson. The parts to undergo scrapping are unpacked in the material lock, and then go into the scrapping caisson. It is possible to use here various mechanical and thermal methods to dismantle the respective parts. But most of the parts to undergo scrapping are such as that it is possible to directly pretreat them in the crusher. The obtained scrap is loaded into 180-liter drums. Most of the machinery in the caisson is manually operated. The operating crew enters the caisson in fully ventilated protective overalls. The drums filled with the scrap then go to the high-pressure compactor in the caisson. The compacts are temporarily stored, until recalled depending on their height and filled into drums such as that optimal drum filling is guaranteed

  8. Operating experience in nuclear power plants

    Anon.

    1984-01-01

    The nuclear power plants in the Federal Republic of Germany kept their portion of power supply into the public grid system constant in 1983, compared to 1982. The generation had an absolute increase of 3.6% and amounts now to 65.9 TWh. Particularly mentioned should be the generation of the Grafenrheinfeld Nuclear Power Plant which is holding the 'World Record' with 9.969 TWh. The availability of the plants was generally satisfactory, as far as long-term retrofit measures with long outage periods were not necessary, as it was the case in Brunsbuettel and Wuergassen. The planned retrofit phases have been completed in all power plants. As far as safety is concerned, there was no reason to recommended a change of the present fundamental planning- and operation aspects. (orig.) [de

  9. Operational experience of gamma radiation processing facility

    Patel, Nilesh

    2014-01-01

    Universal lSO-MED is now proud to announce an extension of its irradiation service for low-dose applications specifically in agriculture commodities, food and healthcare applications with the start of Gujarat Agro Radiation Processing Facility at Village: Bavla, Ahmedabad (A Government Enterprise) Operated, Maintained and Managed by Universal Medicap Ltd. Availability of hygienic, safe and nutritious food commodities is essential for any sustainable human development. Food stability is an important element of economic stability and self-reliance of a nation. Though the need to preserve food has been felt by the mankind since the time immemorial, it is even stronger in today's context. The rising population and increasing gap between demand and supply, agro-climatic conditions, in adequate post-harvest practices, seasonal nature of produce and long distances between production and consumption centers underscore the need to device improved conservation and preservation strategies

  10. Operating experience from Swedish nuclear power plants

    NONE

    1999-06-01

    The total production of electricity from Swedish nuclear power plants was 70.5 TWh during 1998, which is the second highest yearly production ever. Production losses due to low demand totaled 5.1 TWh combined for all twelve units and production losses due to coastdown operation totaled an additional 0.5 TWh. The reason for this low power demand was a very good supply of water to the hydropower system. Hydroelectric power production was 73.6 TWh, an increase by roughly 5 TWh since 1997. Hence, the hydroelectric power production substantially exceeded the 64 TWh expected during a normal year, i.e. a year with average rainfall. Remaining production sources, mainly fossil fuel electricity production combined with district heating, contributed with 10 TWh. The total electricity production was 154.2 TWh, the highest yearly production ever. The total electricity consumption including transmission losses was 143.5 TWh. This is also the highest consumption ever and an increase by one percent compared to 1997. The preliminary net result of the electric power trade shows a net export by 10.7 TWh. The figures above are calculated from the preliminary production results. A comprehensive report on electric power supply and consumption in Sweden is given in the 1998 Annual Report from the Swedish Power Association. Besides Oskarshamn 1, all plants have periodically been operated in load-following mode, mostly because of the abundant supply of hydropower. The energy availability for the three boiling water reactors at Forsmark averaged 93.3 % and for the three pressure water reactors at Ringhals 91.0 %, both figures are the highest ever noted. In the section `Special Reports` three events of importance to safety that occurred during 1998 are reported. The events were all rated as level 1 according to the International Nuclear Event Scale (INES) Figs, tabs.; Also available in Swedish

  11. Operating experience from Swedish nuclear power plants

    1999-01-01

    The total production of electricity from Swedish nuclear power plants was 70.5 TWh during 1998, which is the second highest yearly production ever. Production losses due to low demand totaled 5.1 TWh combined for all twelve units and production losses due to coastdown operation totaled an additional 0.5 TWh. The reason for this low power demand was a very good supply of water to the hydropower system. Hydroelectric power production was 73.6 TWh, an increase by roughly 5 TWh since 1997. Hence, the hydroelectric power production substantially exceeded the 64 TWh expected during a normal year, i.e. a year with average rainfall. Remaining production sources, mainly fossil fuel electricity production combined with district heating, contributed with 10 TWh. The total electricity production was 154.2 TWh, the highest yearly production ever. The total electricity consumption including transmission losses was 143.5 TWh. This is also the highest consumption ever and an increase by one percent compared to 1997. The preliminary net result of the electric power trade shows a net export by 10.7 TWh. The figures above are calculated from the preliminary production results. A comprehensive report on electric power supply and consumption in Sweden is given in the 1998 Annual Report from the Swedish Power Association. Besides Oskarshamn 1, all plants have periodically been operated in load-following mode, mostly because of the abundant supply of hydropower. The energy availability for the three boiling water reactors at Forsmark averaged 93.3 % and for the three pressure water reactors at Ringhals 91.0 %, both figures are the highest ever noted. In the section 'Special Reports' three events of importance to safety that occurred during 1998 are reported. The events were all rated as level 1 according to the International Nuclear Event Scale (INES)

  12. Impact of LMFBR operating experience on PFBR design

    Bhoje, S.B.; Chetal, S.C.; Chellapandi, P.; Govindarajan, S.; Lee, S.M.; Kameswara Rao, A.S.L.; Prabhakar, R.; Raghupathy, S.; Sodhi, B.S.; Sundaramoorthy, T.R.; Vaidyanathan, G.

    2000-01-01

    PFBR is a 500 MWe, sodium cooled, pool type, fast breeder reactor currently under detailed design. It is essential to reduce the capital cost of PFBR in order to make it competitive with thermal reactors. Operating experience of LMFBRs provides a vital input towards simplification of the design, improving its reliability, enhancing safety and achieving overall cost reduction. This paper includes a summary of LMFBR operating experience and details the design features of PFBR as influenced by operating experience of LMFBRs. (author)

  13. Operating experience with nuclear power plants 2015. Pt. 1

    Anon.

    2016-07-01

    The VGB Technical Committee ''Nuclear Plant Operation'' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2015, events important to plant safety, special and relevant repair, and retrofit measures from Germany. The second part of this report will focus on nuclear power plant in Belgium, Finland, the Netherlands, Switzerland, and Spain.

  14. Operating experience and construction status of ATLAS

    Pardo, R.C.; DenHartog, P.; Shepard, K.W.; Zinkann, G.

    1984-01-01

    The present Argonne Tandem-Linac accelerator has operated in a reliable manner during the past year. The accelerator system provided 4402 hours of experimental beam time with a wide variety of heavy-ions. Figure 1 shows the beams which have been provided during the past year. New beams accelerated by the linac include 300 MeV 82 Se and 390 MeV 109 Ag. In tests, the tandem accelerated 102 MeV 127 I. This is the heaviest beam ever accelerated by the Argonne tandem. The long-term performance of the niobium resonators appears to be good. No significant degradation of performance has been observed for most resonators over many years of use with the exceptions of problems caused by catastrophic vacuum accidents. Resonators whose performance has deteriorated after vacuum accidents have recently been restored to their original performance state by a simple technique. The technique used is to rinse the interior of the resonator with a sequence of baths of solvents and water

  15. HDS unit revamp and operating experience

    Reinhardt, J. [Veba Oel Verarbeitungs-GmbH, Gelsenkirchen (Germany); Balfanz, U. [Aral Forschung, Gelsenkirchen (Germany); Dimmig, T. [TU Bergakademie Freiberg, Freiberg (Germany)

    2002-12-01

    Ruhr Oel GmbH, a joint venture between BP and PDVSA, operates a HDS unit at its Gelsenkirchen-Scholven site. The unit produces a major blend component for diesel fuel. Driven by ambitious German environmental policy and by an agreement between the German car and oil industries on the one hand and the government on the other, more stringent low sulphur fuel specifications will be enforced in Germany much earlier than in the rest of the European Union. In view of this situation a project was developed to fulfill the new product specifications with minimum investment. In a joint effort involving the refinery, the company research facilities and the catalyst supplier (AKZO NOBEL), pilot plant tests were performed to develop the best catalyst system and the new process conditions. Based on these results, an existing HDS unit was accordingly revamped. After the revamp, the unit produced diesel fuel with 50 ppm sulphur content and furthermore test runs at 10 ppm were carried out successfully. These results are displayed in this article. (orig.)

  16. Operational experience at the Sludge Treatment Facility

    Sy, D.J.

    1987-01-01

    The Sludge Treatment Facility (STF) at the Oak Ridge Gaseous Diffusion Plant has been in operation since April 1987. The facility was designed to encapsulate hazardous sludge wastes in a cement matrix. Fixation will allow the waste to meet or exceed applicable compressive strength and leachability requirements. Thus, the grout mixture complies with the Resource Conservation and Recovery Act (RCRA) guidelines as a nonhazardous waste. The grout mixture is based upon a recipe formulation developed after several years of waste stream characterization and formulation studies. The wastes to be treated at the STF are wastes impounded in two ponds. The ponds have a combined capacity of 4.5 million gallons of sludge. The sludge is transferred from the ponds to a 15,000-gallon capacity storage tank by the use of a dredge. The grout mixture recipe dictates the amount of sludge, cement, fly ash, and admixture required for weighing per batch. All ingredients are weighed and then transferred to a tilt or high energy mixer for mixing. The grout mixture is then transferred to 89- or 96-gallon steel drums. The drums are placed in a storage yard designed for a point source discharge from the yard

  17. Fast reactor operating experience gained in Russia: Analysis of anomalies and abnormal operation cases

    Ashurko, Y.M.; Baklushin, R.P.; Zagorulko, Y.I.; Ivanenko, V.N.; Matveyev, V.P.; Vasilyev, B.A.

    2000-01-01

    Review of various anomalous events and abnormal operation experience gained in the process of Russian fast reactors operation is given in the paper. The main information refers to the BN-600 demonstration reactor operation. Statistical data on sodium leaks and steam generator failures are presented, and sources of these events and countermeasures taken to avoid their appearance on the operating reactors as well as related changes made in the BN-800 reactor design are considered. In the paper, some features of impurities behaviour are considered in various modes of the BN-600 reactor operation. Information is given on the impurities ingress into the circuits, on abnormal situation emerged in the process of the BN-600 reactor operation and its probable cause. Information is presented on the event related to the increased torque of the BN-600 reactor central rotating column and repair works performed. (author)

  18. Incorporating operational experience and design changes in availability forecasts

    Norman, D.

    1988-01-01

    Reliability or availability forecasts which are based solely on past operating experience will be precise if the sample is large enough, and unbiased if nothing in the future design, environment, operating region or anything else changes. Unfortunately, life is never like that. This paper considers the methodology and philosophy of modifying forecasts based on past experience to take account also of changes in design, construction methods, operating philosophy, environments, operator training and so on, between the plants which provided the operating experience and the plant for which the forecast is being made. This emphasises the importance of collecting, assessing, and learning from past data and of a thorough knowledge of future designs, and procurement, operation, and maintenance policies. The difference between targets and central estimates is also discussed. The paper concludes that improvements in future availability can be made by learning from past experience, but that certain conditions must be fulfilled in order to do so. (author)

  19. Proceedings of 2nd PHWR operating safety experience meeting

    NONE

    1991-04-01

    Papers presented during the eight sessions of the meeting were devoted to the impact of PHWR operating experience on design of civil structures (reactor building integrity); operating experiences related to pressure tubes, nuclear steam supply system, plant stability; reactor maintenance and control systems, reactor operational safety. Some events concerned with reactor shutdown due to power failures are described, as well as action undertaken to prevent major damage.

  20. Operating experience with high beta superconducting RF cavities

    Dylla, H.F.; Doolittle, L.R.; Benesch, J.F.

    1993-01-01

    The number of installed and operational β=1 superconducting rf cavities has grown significantly over the last two years in accelerator laboratories in Europe, Japan and the U.S. The total installed acceleration capability as of mid-1993 is approximately 1 GeV at nominal gradients. Major installations at CERN, DESY, KEK and CEBAF have provided large increments to the installed base and valuable operational experience. A selection of test data and operational experience gathered to date is reviewed

  1. Natural uranium metallic fuel elements: fabrication and operating experience

    Hammad, F.H.; Abou-Zahra, A.A.; Sharkawy, S.W.

    1980-01-01

    The main reactor types based on natural uranium metallic fuel element, particularly the early types, are reviewed in this report. The reactor types are: graphite moderated air cooled, graphite moderated gas cooled and heavy water moderated reactors. The design features, fabrication technology of these reactor fuel elements and the operating experience gained during reactor operation are described and discussed. The interrelation between operating experience, fuel design and fabrication was also discussed with emphasis on improving fuel performance. (author)

  2. Large remote manipulator operating and maintenance experience at IEM cell

    Hicks, D.F.; McGuinness, P.W.

    1985-01-01

    The Interim Examination and Maintenance (IEM) Cell at the Fast Flux Test Facility (FFTF) has two large Electro-Mechanical Manipulators (EMM's). These manipulators are used for cell operations (processing of reactor core components) as well as general cell maintenance. From our eleven years of operation and maintenance experience with these large EMM's, we have learned many lessons concerning manipulator design. This paper describes the IEM Cell EMM design features and discusses operating and maintenance experience at the IEM Cell

  3. Operating experience with high beta superconducting rf cavities

    Dylla, H.F.; Doolittle, L.R.; Benesch, J.F.

    1993-06-01

    The number of installed and operational β = 1 superconducting rf cavities has grown significantly over the last two years in accelerator laboratories in Europe, Japan and the US. The total installed acceleration capability as of mid-1993 is approximately 1 GeV at nominal gradients. Major installations at CERN, DESY, KEK and CEBAF have provided large increments to the installed base and valuable operational experience. A selection of test data and operational experience gathered to date is reviewed

  4. Proceedings of 2nd PHWR operating safety experience meeting

    1991-04-01

    Papers presented during the eight sessions of the meeting were devoted to the impact of PHWR operating experience on design of civil structures (reactor building integrity); operating experiences related to pressure tubes, nuclear steam supply system, plant stability; reactor maintenance and control systems, reactor operational safety. Some events concerned with reactor shutdown due to power failures are described, as well as action undertaken to prevent major damage

  5. ETSON proposal on the European operational experience feedback system

    Maqua, Michael; Bertrand, Remy; Gelder, Pieter de

    2007-01-01

    The new IAEA Safety Fundamentals states regarding the operating experience feedback: The feedback of operating experience from facilities and activities - and, where relevant, from elsewhere - is a key means of enhancing safety. Processes must be put in place for the feedback and analysis of operating experience, including initiating events, accident precursors, near misses, accidents and unauthorized acts, so that lessons may be learned, shared and acted upon. This presentation deals with the proposal of the ETSON (European TSO Network) to optimize the European operating experiences feedback (OEF). It is generally recognized that the efficiency of nuclear safety supervision by public authorities is based on two key requirements: - the existence of a competent authority at national level, benefiting from an appropriate legislative and regulatory basis, from adequate (quantitatively and qualitatively) human resources, particularly for inspection purposes, - the availability of resources devoted to highly specialised independent technical expertise, in order to provide competent authorities with pertinent technical opinions on: -- the safety files provided by operators, for the purpose of licensing corresponding activities, -- the exploitation for regulatory purposes of the operating experience feed back from licensed nuclear installations. There are two worldwide systems intended to learn lessons from experience: the WANO (World Association of Nuclear Operators) system established by the licensees with access restricted to operating organizations and the IRS system jointly operated by IAEA and OECD/NEA accessible to regulators and to some other users nominated by the regulators in their countries. The IRS itself is dedicated to the analysis of safety significant operating events. NEA/CNRA runs a permanent working group on operating experience (WGOE). WGOE provides among other things also generic reports on safety concerns related to operating experiences and

  6. BN-600 power unit 15-year operating experience

    Saraev, O.M.; Oshkanov, N.N.; Vylomov, V.V.

    1996-01-01

    Comprehensive experience has been gained with the operating fast reactor BN-600 with a power out of 600 MWe. This paper includes important performance results and gives also an overview of the experience gained from BN-600 NPP commercial operation during 15 years. (author). 2 figs, 1 tab

  7. Annual meeting on nuclear technology 1980. Technical meeting: Operating experiences

    1980-01-01

    In addition to general experiences, experiences in reactor operation with relation to the Phenix reactor, KNK-2 reactor, the AVR reactor, the BWR-type KKI-reactor, the Philippsburg-1 reactor and the Obrigheim reactor are described. (DG) [de

  8. [Operating Room Nurses' Experiences of Securing for Patient Safety].

    Park, Kwang Ok; Kim, Jong Kyung; Kim, Myoung Sook

    2015-10-01

    This study was done to evaluate the experience of securing patient safety in hospital operating rooms. Experiential data were collected from 15 operating room nurses through in-depth interviews. The main question was "Could you describe your experience with patient safety in the operating room?". Qualitative data from the field and transcribed notes were analyzed using Strauss and Corbin's grounded theory methodology. The core category of experience with patient safety in the operating room was 'trying to maintain principles of patient safety during high-risk surgical procedures'. The participants used two interactional strategies: 'attempt continuous improvement', 'immersion in operation with sharing issues of patient safety'. The results indicate that the important factors for ensuring the safety of patients in the operating room are manpower, education, and a system for patient safety. Successful and safe surgery requires communication, teamwork and recognition of the importance of patient safety by the surgical team.

  9. Long-term operating experience for the ATLAS superconducting resonators

    Pardo, R.; Zinkann, G.

    1999-01-01

    Portions of the ATLAS accelerator have been operating now for over 21 years. The facility has accumulated several million resonator-hours of operation at this point and has demonstrated the long-term reliability of RF superconductivity. The overall operating performance of the ATLAS facility has established a level of beam quality, flexibility, and reliability not previously achieved with heavy-ion accelerator facilities. The actual operating experience and maintenance history of ATLAS are presented for ATLAS resonators and associated electronics systems. Solutions to problems that appeared in early operation as well as current problems needing further development are discussed

  10. Dry cooling tower operating experience in the LOFT reactor

    Hunter, J.A.

    1980-01-01

    A dry cooling tower has been uniquely utilized to dissipate heat generated in a small experimental pressurized water nuclear reactor. Operational experience revealed that dry cooling towers can be intermittently operated with minimal wind susceptibility and water hammer occurrences by cooling potential steam sources after a reactor scram, by isolating idle tubes from the external atmosphere, and by operating at relatively high pressures. Operating experience has also revealed that tube freezing can be minimized by incorporating the proper heating and heat loss prevention features

  11. Commissioning and Operational Experience in Power Reactor Fuel Reprocessing Plant

    Pradhan, S., E-mail: spradhan@barctara.gov.in [Tarapur Based Reprocessing Plant, Bhabha Atomic Research Centre, Tarapur (India)

    2014-10-15

    After completing design, construction, commissioning, operation and maintenance experience of the reprocessing plants at Tarapur, Mumbai and Kalpakkam a new reprocessing plant is commissioned and put into operation at BARC, Tarapur since 2011. Subsequent to construction clearance, commissioning of the plant is taken in many steps with simultaneous review by design and safety committees. In spite of vast experience, all the staff was retrained in various aspects of process and utility operations and in operation of innovative changes incorporated in the design. Operating personnel are licensed through an elaborate procedure consisting of various check lists followed by personnel interview. Commissioning systems were divided in sub-systems. Sub-systems were commissioned independently and later integrated testing was carried out. For commissioning, extreme operating conditions were identified in consultation with designers and detailed commissioning procedures were made accordingly. Commissioning was done in different conditions to ensure safety, smooth operation and maintainability. Few modifications were carried out based on commissioning experience. Technical specifications for operation of the plant are made in consultation with designers and reviewed by safety committees. Operation of the plant was carried out after successful commissioning trials with Deep Depleted Uranium (DDU). Emergency operating procedures for each design basis accident were made. Performance of various systems, subsystems are quite satisfactory and the plant has given very good capacity factor. (author)

  12. Operational experiences feedback in Bohunice NPP

    Betak, A [NPP Bohunice (Slovakia)

    1997-10-01

    The presentation reviews the following issues: OEF team in Bohunice NPP - structure; training and qualification: ASSET seminars on Prevention of incidents - INES manual handling, NRA-NRC the training on event investigation methods, NU - the training on HPES; legislation - documentation prepared in the frame of QA programme; results of OEF team activities; ASSET mission Dukovany - Experiences; the perspective activities.

  13. Operational experience in water chemistry of PHWRs

    Krishna Rao, K.S.

    2000-01-01

    The chemistry related problems encountered in the moderator, primary heat transport systems, chemical control in the steam generators and the experience gained in the decontamination campaigns carried out in the primary heat transport systems of Indian PHWRs are highlighted in this paper. (author)

  14. Spacelab operations planning. [ground handling, launch, flight and experiments

    Lee, T. J.

    1976-01-01

    The paper reviews NASA planning in the fields of ground, launch and flight operations and experiment integration to effectively operate Spacelab. Payload mission planning is discussed taking consideration of orbital analysis and the mission of a multiuser payload which may be either single or multidiscipline. Payload analytical integration - as active process of analyses to ensure that the experiment payload is compatible to the mission objectives and profile ground and flight operations and that the resource demands upon Spacelab can be satisfied - is considered. Software integration is touched upon and the major integration levels in ground operational processing of Spacelab and its experimental payloads are examined. Flight operations, encompassing the operation of the Space Transportation System and the payload, are discussed as are the initial Spacelab missions. Charts and diagrams are presented illustrating the various planning areas.

  15. Operating results and experience and operating regimes in changing demands of energy world

    Hobza, L.

    2004-01-01

    In this paper, there are stated some operating results and experience obtained from trial operation of Temelin NPP. In Europe, Temelin NPP is presently one of the latest implemented projects of the series of VVER 1000 nuclear units with proven V-320 pressurized water reactor. The distinction between Temelin NPP and original project lays mainly in supply of nuclear fuel and in I and C systems delivered by Westinghouse Company. Temelin NPP has passed through commissioning period and trial operation. The main goal of the trial operation was to meet the requirements of section 2, par. 4, point b) of Decree No. 106/98 Sb. and verification of project parameters and stability of operation, and the situation leading to violation of safety functions fulfilment according to Pre-operational Safety Report should not occur. The integral part of trial operation assessment was also successful performing of determined monitoring programmes, first refuelling and performing of prescribed tests and operational inspections. Simultaneously, first experience was obtained with nuclear fuel; providing of ancillary services; reliability of important components; operation of turbine-generator 1000 MW; chemical regime; influence to environment; and quality of contractors. As safety is the most important indicator, it can be stated that: no facts which would lead to decreasing of safety systems operability have been detected; no facts which would lead to negative affecting of barriers against fading the radioactivity into both working areas and environment, have been detected; good condition of fire safety has been continuously documented; requirements of limits for releasing waste water into environment have been continuously complied with; requirements of limits for releasing radioactive substances (in gaseous and/or liquid state) into environment have been continuously complied with. From the operation regimes point of view is clear, that it would be suitable for the power plant if the

  16. International Experience with Fast Reactor Operation & Testing

    Sackett, John I.; Grandy, C.

    2013-01-01

    Conclusion: • Worldwide experience with fast reactors has demonstrated the robustness of the technology and it stands ready for worldwide deployment. • The lessons learned are many and there is danger that what has been learned will be forgotten given that there is little activity in fast reactor development at the present time. • For this reason it is essential that knowledge of fast reactor technology be preserved, an activity supported in the U.S. as well as other countries

  17. Physics experiments with the operating reactor

    Cullington, G R; King, D C

    1973-09-27

    Experimental techniques have been developed and used on Dragon to give consistent information on excess reactivity and shut down margin. The reactivity measurements have been correlated with the theoretical calculations and have led to improvements in the calculations. The methods used and the results obtained are accepted by the Safety Committee as sufficient evidence for compliance with the fuel loading safety rules. Although the reactor was not designed as an experimental facility, flux and dose measurements experiments have been successfully carried out. Mass flow and negative reactivity transient measurements have been carried out. These are valuable for demonstration of the flexibility of the reactor system and for giving confidence in theoretical calculations.

  18. RAS III - concept and operating experience

    Kunze, U.; Wander, J.

    1990-01-01

    A new noise analysis system RAS III is being employed at the Greifswald NPP 'Bruno Leuschner' units 5 and 6 which differs from its forerunner types by an extended number of measuring points and a higher degree of automation. Substantial prerequisite of the system's full efficiency is implementation of efficient signal monitoring techniques that free the power plant engineer from routine work as well. The system has therefore been completed by algorithms established for automatic noise signal spectra control and for monitoring the pressure vessel vibrations. Moreover, a number of special techniques have been developed, such as for recording velocity-time plots during control element drop experiments. (author)

  19. Fire protection system operating experience review for fusion applications

    Cadwallader, L.C.

    1995-12-01

    This report presents a review of fire protection system operating experiences from particle accelerator, fusion experiment, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of fire protection system component failure rates and fire accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with these systems are discussed, including spurious operation. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor

  20. Fire protection system operating experience review for fusion applications

    Cadwallader, L.C.

    1995-12-01

    This report presents a review of fire protection system operating experiences from particle accelerator, fusion experiment, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of fire protection system component failure rates and fire accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with these systems are discussed, including spurious operation. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor.

  1. TSTA Piping and Flame Arrestor Operating Experience Data

    Cadwallader, Lee C.; Willms, R. Scott

    2014-10-01

    The Tritium Systems Test Assembly (TSTA) was a facility dedicated to tritium handling technology and experiment research at the Los Alamos National Laboratory. The facility operated from 1984 to 2001, running a prototype fusion fuel processing loop with ~100 grams of tritium as well as small experiments. There have been several operating experience reports written on this facility’s operation and maintenance experience. This paper describes analysis of two additional components from TSTA, small diameter gas piping that handled small amounts of tritium in a nitrogen carrier gas, and the flame arrestor used in this piping system. The operating experiences and the component failure rates for these components are discussed in this paper. Comparison data from other applications are also presented.

  2. Lessons from feedback of safety operating experience for reactor physics

    Suchomel, J.; Rapavy, S.

    1999-01-01

    Analyses of events in WWER operations as a part of safety experience feedback provide a valuable source of lessons for reactor physics. Examples of events from Bohunice operation will be shown such as events with inadequate approach to criticality, positive reactivity insertions, expulsion of a control rod from shut-down reactor, problems with reactor protection system and control rods. (Authors)

  3. Precision operation of the Nova laser for fusion experiments

    Caird, J.A.; Ehrlich, R.B.; Hermes, G.L.; Landen, O.L.; Laumann, C.W.; Lerche, R.A.; Miller, J.L.; Murray, J.E.; Nielsen, N.D.; Powell, H.T.; Rushford, M.C.; Saunders, R.L.; Thompson, C.E.; VanArsdall, P.J.; Vann, C.S.; Weiland, T.L.

    1994-01-01

    The operation of a Neodymium glass laser of a special design for fusion experiments is improved by a better pulse synchronization, the gain stabilization, and the laser diagnostics. We used sensor upgrading and antifriction coating of focusing lenses. The pointing accuracy of the Nova laser meets now our goal for precision operation. (AIP) copyright 1994 American Institute of Physics

  4. The VEPP-2000 Collider Control System: Operational Experience

    Senchenko, A I; Lysenko, A P; Rogovsky, Yu A; Shatunov, P Yu

    2017-01-01

    The VEPP-2000 collider was commissioned and operated successfully in 2010-2013. During the operation the facility underwent continuous updates and experience in maintenance was acquired. Strong cooperation between the staff of the accelerator complex and the developers of the control system proved effective for implementing the necessary changes in a short time.

  5. Remote maintenance of an operational fusion experiment

    Kiptily, V.G.; Jarvis, O.N.; Popovichev, S. [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon. (United Kingdom)] [and others

    2001-07-01

    Optimisation of auxiliary plasma heating by means of Ion Cyclotron Radio-Frequency (ICRF) and Neutral Beam Injection (NBI) as envisaged for the future fusion reactors is one of the main priorities in present research at today's tokamaks. Therefore, investigation of the production of fast ions during heating and of the subsequent fast ion behaviour in magnetically confined plasmas, together with an evaluation of the resulting bulk ion heating efficiency, are of essential importance for fusion reactor development. Gamma-ray diagnostics, based on the measurement of the gamma-ray emission from nuclear reactions between fast ions and the main plasma impurities, is a valuable technique for studying the fast particle energy distributions. Gamma-ray spectrometry provides information on the energy distribution, and the measurement of emission profiles supplies information on the spatial distribution of the reaction sites. Since 1987, the {gamma}-ray emission from JET plasmas has been systematically monitored and used successfully in the analysis of heating effects during ICRF and NBI heating in the JET tokamak. The classical character of the fast ion slowing down behaviour has been demonstrated and estimates have been obtained of the fast particle confinement time. The study of sawtooth crashes has demonstrated dramatic spatial redistribution of fast particles and other effects. In recent JET experiments to study the ITER-relevant ICRH scenarios ({sup 3}He)D and ({sup 3}He){sup 4}He, {gamma}-ray measurements provided information on the fast ion population, with the effective temperature of the energetic tail ions being deduced with the help of a {gamma}-ray spectrum simulation code, GAMMOD. In this paper, the main y-ray results are presented and the capabilities of gamma diagnostics are discussed in the light of the ITER-project programme.

  6. Risk management for operations of the LANL Critical Experiments Facility

    Paternoster, R.; Butterfield, K.

    1998-01-01

    The Los Alamos Critical Experiments Facility (LACEF) currently operates two burst reactors (Godiva-IV and Skua), one solution assembly [the Solution High-Energy Burst Assembly (SHEBA)], two fast-spectrum benchmark assemblies (Flattop and Big Ten), and five general-purpose remote assembly machines that may be configured with nuclear materials and assembled by remote control. Special nuclear materials storage vaults support these and other operations at the site. With this diverse set of operations, several approaches are possible in the analysis and management of risk. The most conservative approach would be to write a safety analysis report (SAR) for each assembly and experiment. A more cost-effective approach is to analyze the probability and consequences of several classes of operations representative of operations on each critical assembly machine and envelope the bounding case accidents. Although the neutron physics of these machines varies widely, the operations performed at LACEF fall into four operational modes: steady-state mode, approach-to-critical mode, prompt burst mode, and nuclear material operations, which can include critical assembly fuel loading. The operational sequences of each mode are very nearly identical, whether operated on one assembly machine or another. The use of an envelope approach to accident analysis is facilitated by the use of classes of operations and the use of bounding case consequence analysis. A simple fault tree analysis of operational modes helps resolve which operations are sensitive to human error and which are initiated by hardware of software failures. Where possible, these errors and failures are blocked by TSR LCOs. Future work will determine the probability of accidents with various initiators

  7. Radiological operating experience at FFTF [Fast Flux Test Facility

    Bunch, W.L.; Prevo, P.R.

    1986-11-01

    The Fast Flux Test Facility has been in operation for approximately five years, including about one thousand days of full power operation of the Fast Test Reactor. During that time the collective dose equivalents received by operating personnel have been about two orders of magnitude lower than those typically received at commercial light water reactors. No major contamination problems have been encountered in operating and maintaining the plant, and release of radioactive gas to the environment has been minimal and well below acceptable limits. All shields have performed satisfactorily. Experience to date indicates an apparent radiological superiority of liquid metal reactor systems over current light water plants

  8. Feedback of safety - related operational experience: Lessons learned

    Elias, D [Commonwealth Edison Co. (United States)

    1997-09-01

    The presentation considers the following aspects of feedback of safety-related operational experience: lessons learned program, objectives, personnel characteristics; three types of documents for transmitting lessons learned issues.

  9. Feedback of safety - related operational experience: Lessons learned

    Elias, D.

    1997-01-01

    The presentation considers the following aspects of feedback of safety-related operational experience: lessons learned program, objectives, personnel characteristics; three types of documents for transmitting lessons learned issues

  10. The Gerbil Jar: A Basic Home Experience in Operant Conditioning.

    Plant, L.

    1980-01-01

    Explains how a teaching method such as allowing students to raise gerbils at home can encourage students to gain experience with the fundamental techniques of operant conditioning which are otherwise generally unavailable to students in large introductory psychology courses. (DB)

  11. Operations experience with the NAC-1 legal weight truck cask

    Viebrock, J.M.; Hoffman, C.C.

    1978-01-01

    The first three years of operation of Nuclear Assurance Corporation's (NAC) four (4) NAC-1 Casks have demonstrated that shipments of spent fuel, fuel rods and other highly irradiated reactor components can be moved routinely by legal weight truck transport. Shipments of these materials have involved some 800,000 miles of highway travel and cask handling at some fifteen different nuclear facilities. This paper presents details on NAC's operations experience with these casks including cask description, cask handling (loading and unloading), pre-shipment testing, facility turnaround and transit times, operator exposure, transport vehicles and shipper/carrier/cask owner responsibilities, actual experience with regard to facility interfacing requirements and operational procedures. Cask and equipment utilization is discussed together with the methods used to control operation costs and to improve the economics of truck transport

  12. Nuclear power plant operation experience - a feedback programme

    Banica, I.; Sociu, F.; Margaritescu, C.

    1994-01-01

    An effective high quality maintenance programme is required for the safe reliable operation of a nuclear power plant. To achieve the objectives of such a programme, both plant management and staff must be highly dedicated and motivated to perform high quality work at all levels. Operating and maintenance experience data collections and analysis are necessary in order to enhance the safety of the plant and reliability of the structures systems and components throughout their operating life. Significant events, but also minor incident, may reveal important deficiencies or negative trends adverse to safety. Therefore, a computer processing system for collecting, classifying and evaluating abnormal events or findings concerning operating-maintenance and for feeding back the results of the lessons learned from experience into the design and the operation of our nuclear power plant is considered to be of paramount importance. (Author)

  13. EBR-II: twenty years of operating experience

    Lentz, G.L.; Buschman, H.W.; Smith, R.N.

    1985-01-01

    Experimental Breeder Reactor No. 2 (EBR-II) is an unmoderated, sodium-cooled reactor with a design power of 62.5 MWt. For the last 20 years EBR-II has operated safely, has demonstrated stable operating characteristics, has shown excellent performance of its sodium components, and has had an excellent plant factor. These years of operating experience provide a valuable resource to the nuclear community for the development and design of future liquid metal fast reactors. This report provides a brief description of the EBR-II plant and its early operating experience, describes some recent problems of interest to the nuclear community, and also mentions some of the significant operating achievements of EBR-II. Finally, a few words and speculations on EBR-II's future are offered. 4 figs., 1 tab

  14. Recent operating experiences and programs at EBR-II

    Lentz, G.L.

    1984-01-01

    Experimental Breeder Reactor No. II (EBR-II) is a pool-type, unmoderated, sodium-cooled reactor with a design power of 62.5 MWt and an electrical generation capability of 20 MW. It has been operated by Argonne National Laboratory for the US government for almost 20 years. During that time, it has operated safely and has demonstrated stable operating characteristics, high availability, and excellent performance of its sodium components. The 20 years of operating experience of EBR-II is a valuable resource to the nuclear community for the development and design of future LMFBR's. Since past operating experience has been extensively reported, this report will focus on recent programs and events

  15. Duke staff tap into a fund of operating experience

    Anon.

    1997-01-01

    The benefits of the Operating Experience Database (OEDB) allows employees of the nuclear industry to access a fund of operating experience data on-line in order to help them make appropriate management decisions concerning problem solving for various plant-based problems. Recent successful uses include fire protection system design, improving compliance with technical specifications, and reducing unnecessary trips in turbines. It is anticipated that OEDB may well be used in the Ukraine and Russia in the future. (UK)

  16. Feedback of operating experience in nuclear power plants

    NONE

    1995-06-01

    The feedback of operating experience of nuclear facilities to the designers, manufacturers, operators and regulators is one important means of maintaining and improving safety. The Atomic Energy Control Board`s Advisory Committee on Nuclear Safety examined the means for feedback currently being employed, how effective they are and what improvements are advisable. The review found that the need for feedback of operating experience is well recognized within those institutions contributing to the safety of CANDU power reactors, and that the existing procedures are generally effective. Some recommendations, however, are submitted for improvement in the process.

  17. The experience of five years operation of Phenix

    Conte, F.; Lacroix, A.

    1980-01-01

    Two long periods of exceptional operation have satisfied the hopes of the designers and all parameters, power, efficiency, load factor, fuel behaviour, were better than was expected. The experience resulting from the only major incident provided a series of complementary data. Modern technology has need of sanction by experiment. The Phenix type reactor is a tool which is convenient to operate and to maintain. The two aspects of the demonstration, correct operation and ease of maintenance, take a concrete form in the harmlessness of Phenix on men and on the environment. There is no irradiation and few releases. (orig./DG)

  18. Feedback of operating experience in nuclear power plants

    1995-06-01

    The feedback of operating experience of nuclear facilities to the designers, manufacturers, operators and regulators is one important means of maintaining and improving safety. The Atomic Energy Control Board's Advisory Committee on Nuclear Safety examined the means for feedback currently being employed, how effective they are and what improvements are advisable. The review found that the need for feedback of operating experience is well recognized within those institutions contributing to the safety of CANDU power reactors, and that the existing procedures are generally effective. Some recommendations, however, are submitted for improvement in the process

  19. Experience on operational safety improvement of control and operation support systems

    Itoh, N.; Nakagawa, T.; Mano, K.

    1988-01-01

    Japanese nuclear industry started in 1956 and about 30 years have passed since that time. Through these years, we have made a lot of efforts and developments in the field of Control and Instrumentation (C and I) system. The above 30 years and following years can be divided into four major periods. The first one is the period of research, the second of domestic production, the third of improvement, and the fourth of advancement. Improvements of C and I system, which we have made in those periods have made a great contribution to enhancement of reliability, availability and operability of nuclear power plants. Fig. 1 shows TEPCO's nuclear power plant (BWR) construction experience and technical trend of C and I system in Japan. This paper is to introduce the efforts and operational experience on control and operation support systems

  20. Operational safety experience reporting in the United States

    Hartfield, R.A.

    1978-01-01

    Licensees of nuclear power plants in the United States have many reporting requirements included in their technical specifications and the code of federal regulations, title 10. The Nuclear Regulatory Commisson receives these reports and utilizes them in its regulatory program. Part of this usage includes collecting and publishing this operating experience data in various reports and storing information in various data systems. This paper will discuss the data systems and reports on operating experience published and used by the NRC. In addition, some observations on operating experience will be made. Subjects included will be the Licensee Event Report (LER) Data File, the Operating Unit Status Report (Gray Book), Radiation Exposure Reports, Effluents Reports, the Nuclear Plant Reliability Data System, Current Events, Bulletin Wrapups and Annual Summaries. Some of the uses of the reports and systems will be discussed. The Abnormal Occurence Report to the US Congress will also be described and discussed. (author)

  1. Operating Experience Review of Tritium-in-Water Monitors

    S. A. Bruyere; L. C. Cadwallader

    2011-09-01

    Monitoring tritium facility and fusion experiment effluent streams is an environmental safety requirement. This paper presents data on the operating experience of a solid scintillant monitor for tritium in effluent water. Operating experiences were used to calculate an average monitor failure rate of 4E-05/hour for failure to function. Maintenance experiences were examined to find the active repair time for this type of monitor, which varied from 22 minutes for filter replacement to 11 days of downtime while waiting for spare parts to arrive on site. These data support planning for monitor use; the number of monitors needed, allocating technician time for maintenance, inventories of spare parts, and other issues.

  2. Steam generator operating experience update, 1982-1983

    Frank, L.

    1984-06-01

    This report is a continuation of earlier reports by the staff addressing pressurized water reactor steam generator operating experience. NUREG-0886, Steam Generator Tube Experience, published in February 1982 summarized experience in domestic and foreign plants through December 1981. This report summarizes steam generator operating experience in domestic plants for the years 1982 and 1983. Included are new problems encountered with secondary-side loose parts, sulfur-induced stress-assisted corrosion cracking, and flow-induced vibrational wear in the new preheater design steam generators. The status of Unresolved Safety Issues A3, A4, and A5 is also discussed

  3. Operational safety experience feedback by means of unusual event reports

    1996-07-01

    Operational experience of nuclear power plants can be used to great advantage to enhance safety performance provided adequate measures are in place to collect and analyse it and to ensure that the conclusions drawn are acted upon. Feedback of operating experience is thus an extremely important tool to ensure high standards of safety in operational nuclear power plants and to improve the capability to prevent serious accidents and to learn from minor deviations and equipment failures - which can serve as early warnings -to prevent even minor events from occurring. Mechanisms also need to be developed to ensure that operating experience is shared both nationally as well as internationally. The operating experience feedback process needs to be fully and effectively established within the nuclear power plant, the utility, the regulatory organization as well as in other institutions such as technical support organizations and designers. The main purpose of this publication is to reflect the international consensus as to the general principles and practices in the operational safety experience feedback process. The examples of national practices for the whole or for particular parts of the process are given in annexes. The publication complements the IAEA Safety Series No.93 ''Systems for Reporting Unusual Events in Nuclear Power Plants'' (1989) and may also give a general guidance for Member States in fulfilling their obligations stipulated in the Nuclear Safety Convention. Figs, tabs

  4. Operational safety experience feedback by means of unusual event reports

    NONE

    1996-07-01

    Operational experience of nuclear power plants can be used to great advantage to enhance safety performance provided adequate measures are in place to collect and analyse it and to ensure that the conclusions drawn are acted upon. Feedback of operating experience is thus an extremely important tool to ensure high standards of safety in operational nuclear power plants and to improve the capability to prevent serious accidents and to learn from minor deviations and equipment failures - which can serve as early warnings -to prevent even minor events from occurring. Mechanisms also need to be developed to ensure that operating experience is shared both nationally as well as internationally. The operating experience feedback process needs to be fully and effectively established within the nuclear power plant, the utility, the regulatory organization as well as in other institutions such as technical support organizations and designers. The main purpose of this publication is to reflect the international consensus as to the general principles and practices in the operational safety experience feedback process. The examples of national practices for the whole or for particular parts of the process are given in annexes. The publication complements the IAEA Safety Series No.93 ``Systems for Reporting Unusual Events in Nuclear Power Plants`` (1989) and may also give a general guidance for Member States in fulfilling their obligations stipulated in the Nuclear Safety Convention. Figs, tabs.

  5. US nuclear power plant operating cost and experience summaries

    Kohn, W.E.; Reid, R.L.; White, V.S.

    1998-02-01

    NUREG/CR-6577, U.S. Nuclear Power Plant Operating Cost and Experience Summaries, has been prepared to provide historical operating cost and experience information on U.S. commercial nuclear power plants. Cost incurred after initial construction are characterized as annual production costs, representing fuel and plant operating and maintenance expenses, and capital expenditures related to facility additions/modifications which are included in the plant capital asset base. As discussed in the report, annual data for these two cost categories were obtained from publicly available reports and must be accepted as having different degrees of accuracy and completeness. Treatment of inconclusive and incomplete data is discussed. As an aid to understanding the fluctuations in the cost histories, operating summaries for each nuclear unit are provided. The intent of these summaries is to identify important operating events; refueling, major maintenance, and other significant outages; operating milestones; and significant licensing or enforcement actions. Information used in the summaries is condensed from annual operating reports submitted by the licensees, plant histories contained in Nuclear Power Experience, trade press articles, and the Nuclear Regulatory Commission (NRC) web site (www.nrc.gov)

  6. US nuclear power plant operating cost and experience summaries

    Kohn, W.E.; Reid, R.L.; White, V.S.

    1998-02-01

    NUREG/CR-6577, U.S. Nuclear Power Plant Operating Cost and Experience Summaries, has been prepared to provide historical operating cost and experience information on U.S. commercial nuclear power plants. Cost incurred after initial construction are characterized as annual production costs, representing fuel and plant operating and maintenance expenses, and capital expenditures related to facility additions/modifications which are included in the plant capital asset base. As discussed in the report, annual data for these two cost categories were obtained from publicly available reports and must be accepted as having different degrees of accuracy and completeness. Treatment of inconclusive and incomplete data is discussed. As an aid to understanding the fluctuations in the cost histories, operating summaries for each nuclear unit are provided. The intent of these summaries is to identify important operating events; refueling, major maintenance, and other significant outages; operating milestones; and significant licensing or enforcement actions. Information used in the summaries is condensed from annual operating reports submitted by the licensees, plant histories contained in Nuclear Power Experience, trade press articles, and the Nuclear Regulatory Commission (NRC) web site (www.nrc.gov).

  7. Nuclear Power Plant Operating Experience from the IAEA/NEA International Reporting System for Operating Experience 2012-2014

    2018-03-01

    The International Reporting System for Operating Experience (IRS) is an essential element of the international operating experience feedback system for nuclear power plants. Its fundamental objective is to contribute to improving safety of commercial nuclear power plants which are operated worldwide. IRS reports contain information on events of safety significance with important lessons learned which assist in reducing recurrence of events at other plants. This sixth publication, covering the period 2012 - 2014, follows the structure of the previous editions. It highlights important lessons based on a review of the approximately 240 event reports received from the participating countries over this period.

  8. Spanish Power Exchange Market Concepts and Operating Experience

    Gonzalez, J. J.; Gamito, C.

    2000-01-01

    On January, 1st, 1998, the Spanish Electricity Market started operations. All generators, distributors, commercialization companies, and final consumers negotiate al power exchanges either through the spot market or using bilateral contracts. The Spanish Power Exchange Market Operator (Compania Operadora del Mercado Espanol de electricidad, OMEL) is responsible for the management of the market and for the economic settlement and billing of a transactions on the Power Exchange market, and the technical operational process handled by the System Operator. This paper describes in detail the Spanish market principles and the experience gathered through the design, installation and first two years of market operation. The paper presents also the Spanish market results from January 1998 up to December 1999 indicating each specific market results and aggregate statistics. (Author)

  9. Design and operating experiences with 50MW steam generator

    Kawara, M.; Yamaki, H.; Kanamori, A.; Tanaka, K.; Takahashi, T.

    1975-01-01

    The main purpose of the 50 MW steam generator is to have experiences of manufacturing and operation with large scale steam generator including necessary research and development works which can be reflected on the design and fabrication of 'Monju' (Japan 300 MWe prototype LMFBR). The detailed design of the 50 MW steam, generator was begun on March, 1972 and succeeded in the demonstration of 72 hours continuous operation with full power on June, 1974. It has been successfully operated since then, the performances of which have been evaluated through various kinds of tests. In this paper, the following items are mainly discussed system design, thermal and hydraulic design, structure and fabrication and some experiences on testing operation including cleaning and sodium flushing of equipment, sodium level control system, the behavior of hydrogen detection system and general outlook of the performance. (author)

  10. Telescience testbed: Operational support functions for biomedical experiments

    Yamashita, Masamichi; Watanabe, Satoru; Shoji, Takatoshi; Clarke, Andrew H.; Suzuki, Hiroyuki; Yanagihara, Dai

    A telescience testbed was conducted to study the methodology of space biomedicine with simulated constraints imposed on space experiments. An experimental subject selected for this testbedding was an elaborate surgery of animals and electrophysiological measurements conducted by an operator onboard. The standing potential in the ampulla of the pigeon's semicircular canal was measured during gravitational and caloric stimulation. A principal investigator, isolated from the operation site, participated in the experiment interactively by telecommunication links. Reliability analysis was applied to the whole layers of experimentation, including design of experimental objectives and operational procedures. Engineering and technological aspects of telescience are discussed in terms of reliability to assure quality of science. Feasibility of robotics was examined for supportive functions to reduce the workload of the onboard operator.

  11. Design and operating experiences with 50MW steam generator

    Kawara, M; Yamaki, H; Kanamori, A; Tanaka, K; Takahashi, T

    1975-07-01

    The main purpose of the 50 MW steam generator is to have experiences of manufacturing and operation with large scale steam generator including necessary research and development works which can be reflected on the design and fabrication of 'Monju' (Japan 300 MWe prototype LMFBR). The detailed design of the 50 MW steam, generator was begun on March, 1972 and succeeded in the demonstration of 72 hours continuous operation with full power on June, 1974. It has been successfully operated since then, the performances of which have been evaluated through various kinds of tests. In this paper, the following items are mainly discussed system design, thermal and hydraulic design, structure and fabrication and some experiences on testing operation including cleaning and sodium flushing of equipment, sodium level control system, the behavior of hydrogen detection system and general outlook of the performance. (author)

  12. From USA operation experience of industrial uranium-graphite reactors

    Burdakov, N.S.

    1996-01-01

    The review on materials, presented by a group of the USA specialists at the seminar in Moscow on October 9-11, 1995 is considered. The above specialists shared their experience in operation of the Hanford industrial reactors, aimed at plutonium production for atomic bombs. The purpose of the above visit consisted in providing assistance to the Russian specialists by evaluation and modernization of operational conditions safety improvement of the RBMK type reactors. Special attention is paid to the behaviour of the graphite lining and channel tubes with an account of possible channel power interaction with the reactor structural units. The information on the experience of the Hanford reactor operation may be useful for specialists, operating the RBMK type reactors

  13. Flooding PSA with Plant Specific Operating Experiences of Korean PWRs

    Choi, Sun Yeong; Yang, Joon Yull

    2006-01-01

    The purpose of this paper is to update the flooding PSA with Korean plant specific operating experience data and the appropriate estimation method for the flooding frequency to improve the PSA quality. The existing flooding PSA used the NPE (Nuclear Power Experience) database up to 1985 for the flooding frequency. They are all USA plant operating experiences. So an upgraded flooding frequency with Korean specific plant operation experience is required. We also propose a method of only using the PWR (Pressurized Water Reactor) data for the flooding frequency estimation in the case of the flooding area in the primary building even though the existing flooding PSA used both PWR and BWR (Boiled Water Reactor) data for all kinds of plant areas. We evaluate the CDF (Core Damage Frequency) with the modified flooding frequency and compare the results with that of the existing flooding PSA method

  14. Cryogenic system operating experience review for fusion applications

    Cadwallader, L.C.

    1992-01-01

    This report presents a review of cryogenic system operating experiences, from particle accelerator, fusion experiment, space research, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of cryogenic component failure rates and accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with cryogenic systems are discussed, including ozone formation, effects of spills, and modeling spill behavior. This information should be useful to fusion system designers and safety analysts, such as the team working on the International Thermonuclear Experimental Reactor design

  15. LMFBR operational safety: the EBR-II experience

    Sackett, J.I.; Allen, N.L.; Dean, E.M.; Fryer, R.M.; Larson, H.A.; Lehto, W.K.

    1978-01-01

    The mission of the Experimental Breeder Reactor II (EBR-II) has evolved from that of a small LMFBR demonstration plant to a major irradiation-test facility. Because of that evolution, many operational-safety issues have been encountered. The paper describes the EBR-II operational-safety experience in four areas: protection-system design, safety-document preparation, tests of off-normal reactor conditions, and tests of elements with breached cladding

  16. Current operations and experiments at the Tritium Systems Test Assembly

    Bartlit, J.R.; Anderson, J.L.

    1985-01-01

    The Tritium Systems Test Assembly (TSTA) has continued to move toward operation of a fully-integrated, full-sized, computer-controlled fusion fuel processing loop. Concurrent, nonloop experiments have answered important questions on new components and issues such as palladium diffusion membranes, ceramic electrolysis cells, regenerable tritium getters, laser Raman spectroscopy, unregenerable tritium inventory on molecular sieves, tritium contamination problems and decontamination methods, and operating data on reliability, emissions, doses, and wastes generated. 4 refs., 2 figs

  17. Simulator experiments on operator reliability and training effectiveness

    Singh, A. Spurgin, A.J.

    1990-01-01

    This paper discusses some aspects of the Operator Reliability Experiments project sponsored by Electric Power Research Institute. The paper deals with modifications to the HCR correlation which have resulted from the study of operators in responding to nuclear accident scenarios using emergency procedures. The interpretation of time response data and how insights in crew performance can lead to improvements in not only crew performance but also in training effectiveness are discussed

  18. The Clearing House on Operating Experience Feedback (CH-OEF)

    Tanarro Colodron, J.

    2016-01-01

    Full text: The Clearing House on Operating Experience Feedback (CH-OEF) is an online information system that contains three technical databases available only to registered users: 1) Operating Experience Feedback (OEF) records, containing information about events occurred at Nuclear Power Plants; 2) Nuclear Power Plant (NPP) records, containing technical details about NPPs; 3) Documents about operating experience, such as the Topical Operating Experience Reports (TOERs) and the quarterly reports on nuclear power plant events. The main objective of the information system is to develop communication, cooperation and sharing of operating experience amongst the national nuclear regulatory authorities participating in EU Clearinghouse network. The CH-OEF is essential for the preparation and dissemination of the quarterly reports on NPP events. These reports are published every three months and are intended to be complementary to other international reporting systems, containing mainly recent information publicly available. Only events that are considered to be likely to have lessons applicable to EU NPPs or with a real or potential impact on nuclear safety are addressed in the reports. The CH-OEF is a fundamental tool for their preparation, providing specific features for a more efficient sharing of information as well as for facilitating the related discussion and decision making. (author

  19. Concluding from operating experience to instrumentation and control systems

    Pleger, H.; Heinsohn, H.

    1997-01-01

    Where conclusions are drawn from operating experience to instrumentation and control systems, two general statements should be made. First: There have been braekdowns, there have also been deficiencies, but in principle operating experience with the instrumentation and control systems of German nuclear power plants has been good. With respect to the debates about the use of modern digital instrumentation and control systems it is safe to say, secondly, that the instrumentation and control systems currently in use are working reliably. Hence, there is no need at present to replace existing systems for reasons of technical safety. However, that time will come. It is a good thing, therefore, that the use of modern digital instrumentation and control systems is to begin in the field of limiting devices. The operating experience which will thus be accumulated will benefit digital instrumentation and control systems in their qualification process for more demanding applications. This makes proper logging of operating experience an important function, even if it cannot be transferred in every respect. All parties involved therefore should see to it that this operating experience is collected in accordance with criteria agreed upon so as to prevent unwanted surprises later on. (orig.) [de

  20. European Clearinghouse for Nuclear Power Plants Operational Experience Feedback

    Martin Ramos, M.; Noel, M.

    2010-01-01

    In the European Union, in order to support the Community activities on operational experience, a centralized regional network on nuclear power plants operational experience feedback (European Clearinghouse on Operational Experience Feedback for Nuclear Power Plants) was established in 2008 at the EC JRC-IE, Petten (The Netherlands) on request of nuclear Safety Authorities of several Member States. Its main goal is to improve the communication and information sharing on OEF, to promote regional collaboration on analyses of operational experience and dissemination of the lessons learned. The enlarged EU Clearinghouse was launched in April 2010, and it is currently gathering the Regulatory Authorities of Finland, Hungary, Lithuania, the Netherlands, Romania, Slovenia, Switzerland, Bulgaria, Czec Republic, France, Germany, Slovak Republic, and Spain (these last six countries as observers). The OECD Nuclear Energy Agency, the IAEA, the EC Directorates General of the JRC and ENER are also part of the network. Recently, collaboration between some European Technical Support Organizations (such IRSN and GRS) and the EU Clearinghouse has been initiated. This paper explains in detail the objectives and organization of the EU Clearinghouse, as well as the most relevant activities carried out, like research work in trend analysis of events ocurred in NPP, topical reports on particular events, dissemination of the results, quarterly reports on events reported publicly and operational experience support to the members of the EU Clearinghouse. (Author)

  1. Operating experience on radiation reduction in the latest BWRs

    Ohsumi, K.; Uchida, S.; Aizawa, M.; Takagi, K.; Amano, O.; Yamashita, K.

    1988-01-01

    In Japan, BWR plants have been operated commercially since 1970, and the reduction of radiation exposure has been an important concern. The application of the procedure for reducing occupational exposure is incorporated in Japanese Improvement and Standardization Program for LWRs. No.2 and No.4 plants in Fukushima No.2 Nuclear Power Station were designed and constructed as the latest 1,100 MWe BWRs in conformity with the Improvement and Standardization Program. No.2 plant began the commercial operation in February, 1984, and experienced three times of the scheduled annual maintenance outage. No.4 plant began the commercial operation in September, 1987, and the first annual maintenance is scheduled from September, 1988. In this paper, discussion is focused on recent radiation reduction measures, that is the control of iron and nickel in primary coolant for reducing the radiation dose rate in primary systems, based on the experience with No.2 and No.4 plants. The design concept of a low radiation dose rate nuclear power plant, the experience on water chemistry in No.2 plant, the control of iron and nickel in No.4 plant operation and so on are reported. It is believed that these operation experiences contribute to the reduction of occupational exposure in BWR plants currently in operation and in future. (Kako, I.)

  2. Ventilation Systems Operating Experience Review for Fusion Applications

    Cadwallader, L.C.

    1999-01-01

    This report is a collection and review of system operation and failure experiences for air ventilation systems in nuclear facilities. These experiences are applicable for magnetic and inertial fusion facilities since air ventilation systems are support systems that can be considered generic to nuclear facilities. The report contains descriptions of ventilation system components, operating experiences with these systems, component failure rates, and component repair times. Since ventilation systems have a role in mitigating accident releases in nuclear facilities, these data are useful in safety analysis and risk assessment of public safety. An effort has also been given to identifying any safety issues with personnel operating or maintaining ventilation systems. Finally, the recommended failure data were compared to an independent data set to determine the accuracy of individual values. This comparison is useful for the International Energy Agency task on fusion component failure rate data collection

  3. Design improvements, construction and operating experience with BWRs in Japan

    Uchigasaki, G.; Yokomi, M.; Sasaki, M.; Aoki, R.; Hashimoto, H.

    1983-01-01

    (1) The first domestic-made 1100-MW(e) BWR in Japan commenced commercial operation in April 1982. The unit is the leading one of the subsequent three in Fukushima Daini nuclear power station owned by the Tokyo Electric Power Company Inc. (Tepco). Based on the accumulated construction and operation experience of 500-MW(e) and 800-MW(e) class BWRs, improvements in various aspects during both the design and construction stages were introduced in core and fuel design with advanced gadolinia distribution, reactor feedwater treatment technology for crud reduction, a radwaste island, control and instrumentation to cope with the lessons learned through Three Mile Island assessment etc. (2) Based on many operating experiences with BWRs, an improved BWR core, which has easier operability and higher load factor than the conventional core, has been developed. The characteristic of the improved core is ''axially two-zoned uranium enrichment distribution''; the enrichment of the upper part of the fuel is slightly higher than that of the lower part. Through the improved core it became possible to optimize the axial power flattening and core reactivity control separately by axial enrichment distribution and burnable poison content. The improved fuels were loaded into operating BWRs and successfully proved the performance by this experience. (3) To shorten annual outage time, to reduce radiation exposure, to save manpower, and to achieve high reliability and safety of inspection operation, the remote automatic service and inspection equipment were developed in Japan. This paper presents the concept, distinctive features, and actual operation experience of the automatic refuelling machine, control-rod drive (CRD) remote-handling machine, improved main steam line isolation plug, and the automated ultrasonic inspection system with a computerized data processing unit, which have been developed by Hitachi, Ltd. with excellent results. (author)

  4. Experiences of operation for Ikata Nuclear Power Station

    Kashimoto, Shigeyuki

    1979-01-01

    No. 1 plant in the Ikata Nuclear Power Station, Shikoku Electric Power Co., Inc., is a two-loop PWR unit with electric output of 566 MW, and it began the commercial operation on September 30, 1977, as the first nuclear power station in Shikoku. It is the 13th LWR and 7th PWR in Japan. The period of construction was 52 months since it had been started in June, 1973. During the period, it became the object of the first administrative litigation to seek the cancellation of permission to install the reactor, and it was subjected to the influence of the violent economical variation due to the oil shock, but it was completed as scheduled. After the start of operation, it continued the satisfactory operation, and generated about 2.35 billion KWh for 4300 operation hours. It achieved the rate of utilization of 96.7%. Since March 28, 1978, the first periodical inspection was carried out, and abnormality was not found in the reactor, the steam generator and the fuel at all. The period of inspection was 79 days and shorter than expected. The commercial operation was started again on June 14. The outline of the Ikata Nuclear Power Station, its state of operation, and the periodical inspection are reported. Very good results were able to be reported on the operation for one year, thanks to the valuable experiences offered by other electric power companies. (Kako, I.)

  5. Operating experience with superconducting cavities at Jefferson Lab

    Reece, C.E.

    1998-01-01

    The CEBAF recirculating superconducting electron linac at Jefferson Lab is now in full operation supporting nuclear physics experiments in three target halls at up to 4.4 GeV. The 330 SRF cavities, operating at 2.0 K, continue to perform well above design specifications, and have accumulated over 8,000,000 operating cavity hours. The authors have to date no evidence of degradation of cavity performance. The SRF cavities have demonstrated excellent reliability. The one klystron per cavity design provides CEBAF with flexibility and redundancy for normal operations. Several techniques have been developed for establishing optimum operating conditions for the 330 independent systems. Operation of the cavities and control systems at the full design current of 1 mA has recently been achieved. The principal constraints on usable gradient for low current operations are (1) discharge at the cold ceramic rf window induced by electron field emission in cavities, (2) tuner controls, and (3) stability of the waveguide vacuum in the region between the warm and cold windows. Several cryomodules have been improved by application of rf helium processing while installed on the beamline

  6. Review and updates of the risk assessment for advanced test reactor operations for operating events and experience

    Atkinson, S.A.

    1996-01-01

    Annual or biannual reviews of the operating history of the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL) have been conducted for the purpose of reviewing and updating the ATR probabilistic safety assessment (PSA) for operating events and operating experience since the first compilation of plant- specific experience data for the ATR PSA which included data for operation from initial power operation in 1969 through 1988. This technical paper briefly discusses the means and some results of these periodic reviews of operating experience and their influence on the ATR PSA

  7. Configuration control during plant outages. A review of operating experience

    Peinador Veira, Miguel; El Kanbi, Semir [European Commission Joint Research Centre, Petten (Netherlands). Inst. for Energy and Transport; Stephan, Jean-Luc [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Martens, Johannes [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Koeln (Germany)

    2015-03-15

    After the occurrence of several significant events in nuclear power plants during shut-down modes of operation in the eighties, and from the results of probabilistic safety assessments completed in the nineties, it was clear that risk from low power and shutdown operational modes could not be neglected and had to be addressed by appropriate safety programs. A comprehensive review of operating experience from the last ten years has been conducted by the Joint Research Centre with the objective of deriving lessons learned and recommendations useful for nuclear regulatory bodies and utilities alike. This paper is focused on one particular challenge that any nuclear plant faces whenever it plans its next outage period: how to manage the configuration of all systems under a complex environment involving numerous concurrent activities, and how to make sure that systems are returned to their valid configuration before the plant resumes power operation. This study highlights the importance of conveying accurate but synthesized information on the status of the plant to the operators in the main control room. Many of the lessons learned are related to the alarm display in the control room and to the use of check lists to control the status of systems. Members of the industry and safety authorities may now use these recommendations and lessons learned to feed their own operating experience feedback programs, and check their applicability for specific sites.

  8. Recent operating experiences with steam generators in Japanese NPPs

    Yashima, Seiji

    1997-01-01

    In 1994, the Genkai-3 of Kyushu Electric Power Co., Inc. and the Ikata-3 of Shikoku Electric Power Co., Inc. started commercial operation, and now 22 PWR plants are being operated in Japan. Since the first PWR plant now 22 PWR plants are being operated in was started to operate, Japanese PWR plants have had an operating experience of approx. 280 reactor-years. During that period, many tube degradations have been experienced in steam generators (SGs). And, in 1991, the steam generator tube rupture (SGTR) occurred in the Mihama-2 of Kansai Electric Power Co., Inc. However, the occurrence of tube degradation of SGs has been decreased by the instructions of the MITI as regulatory authorities, efforts of Electric Utilities, and technical support from the SG manufacturers. Here the author describes the recent SGs in Japan about the following points. (1) Recent Operating Experiences (2) Lessons learned from Mihama-2 SGTR (3) SG replacement (4) Safety Regulations on SG (5) Research and development on SG

  9. Development of new HRA methods based upon operational experience

    Cooper, S.E.; Luckas, W.J.; Barriere, M.T.; Wreathall, J.

    2004-01-01

    Under the auspices of the US Nuclear Regulatory Commission (NRC), previously unaddressed human reliability issues are being investigated in order to support the development of human reliability analysis (HRA) methods for both low power and shutdown (LP and S) and full-power conditions. Actual operational experience, such as that reported in Licensee Event Reports (LERs), have been used to gain insights and provide a basis for the requirements of new HRA methods. In particular, operational experience has shown that new HRA methods for LP and S must address human-induced initiators, errors of commission, mistakes (vs. slips), dependencies, and the effects of multiple performance shaping factors (PSFs). (author)

  10. Operating experience of Fugen-HWR in Japan

    Yoshino, F.

    1991-01-01

    Fugen is a 165 MWe prototype heavy water reactor which mainly uses plutonium-uranium mixed oxide (MOX) fuel. Power Reactor and Nuclear Fuel Development Corporation (PNC) has taken responsibility for the advanced thermal reactor (ATR) project, with its name 'FUGEN' taken from the Buddhist God of Mercy. The project started in October 1967, to develop and establish the technology for this new type of reactor and to clarify MOX fuel performance in the reactor. Site construction began in December 1970 at Tsuruga and the plant commenced commercial operation on March 20, 1979. Since then, Fugen has been operated successfully for more than twelve years. The plant performance and reliability of this type of reactor has been demonstrated through the operation. All these operational experiences have contributed to the establishment of the ATR technology

  11. Operating experience of Fugen-HWR in Japan

    Yoshino, F [Reactor Regulation Division, Nuclear Safety Bureau, Science and Technology Agency, Tokyo (Japan)

    1991-04-01

    Fugen is a 165 MWe prototype heavy water reactor which mainly uses plutonium-uranium mixed oxide (MOX) fuel. Power Reactor and Nuclear Fuel Development Corporation (PNC) has taken responsibility for the advanced thermal reactor (ATR) project, with its name 'FUGEN' taken from the Buddhist God of Mercy. The project started in October 1967, to develop and establish the technology for this new type of reactor and to clarify MOX fuel performance in the reactor. Site construction began in December 1970 at Tsuruga and the plant commenced commercial operation on March 20, 1979. Since then, Fugen has been operated successfully for more than twelve years. The plant performance and reliability of this type of reactor has been demonstrated through the operation. All these operational experiences have contributed to the establishment of the ATR technology.

  12. Operating experience with superconducting cavities at the TESLA test facility

    Moeller, Wolf-Dietrich

    2003-01-01

    A description of the TESLA Test Facility, which has been set up at DESY by the TeV Energy Superconducting Accelerator (TESLA) collaboration, will be given as it is now after five years of installation and operation. The experience with the first three modules, each containing 8 superconducting 9-cell cavities, installed and operated in the TTF-linac will be described. The measurements in the vertical and horizontal cryostats as well as in the modules will be compared. Recent results of the operation at the TESLA design current, macropulses of 800 μsec with bunches of 3.2 nC at a rate of 2.25 MHz are given. New measurement results of the higher order modes (HOM) will be presented. The operation and optimisation of the TTF Free Electron Laser (TTF-FEL) will also be covered in this paper. (author)

  13. Safety review of experiments at Albuquerque Operations Office

    Elliott, K.

    1984-01-01

    The Department of Energy (DOE) Albuquerque Operations Office is responsible for the safety overview of nuclear reactor and critical assembly facilities at Sandia National Laboratories, Los Alamos National Laboratory, and the Rocky Flats Plant. The important safety concerns with these facilities involve the complex experiments that are performed, and that is the area emphasized. A determination is made by the Albuquerque Office (AL) with assistance from DOE/OMA whether or not a proposed experiment is an unreviewed safety question. Meetings are held with the contractor to resolve and clarify questions that are generated during the review of the proposed experiment. The AL safety evaluation report is completed and any recommendations are discussed. Prior to the experiment a preoperational appraisal is performed to assure that personnel, procedures, and equipment are in readiness for operations. During the experiment, any abnormal condition is reviewed in detail to determine any safety concerns

  14. Operating experience feedback from safety significant events at research reactors

    Shokr, A.M. [Atomic Energy Authority, Abouzabal (Egypt). Egypt Second Research Reactor; Rao, D. [Bhabha Atomic Research Centre, Mumbai (India)

    2015-05-15

    Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

  15. PFR experience of bellows operating in sodium systems

    Hodgson, D.

    1980-01-01

    Although there was little operating experience with bellows in sodium systems available during the design phase of the UK 250 MWe prototype fast reactor, bellows were extensively utilised to seal valves and to overcome the problems of differential thermal movements in several important applications. However, because of this lack of operational experience in sodium and the non-availability of design codes it was considered prudent not to install bellows in situations where failure could possibly initiate events of unpredictable proportions, or in positions where replacement following failure would be extremely difficult i.e. involving complete shutdown of the reactor over an extended period (in excess of six months) and/or necessitate removal of large quantities of primary sodium from the reactor vessel. This paper describes some of the bellows units installed in the PFR and the performance achieved during six years of reactor operation

  16. Operating experience feedback from safety significant events at research reactors

    Shokr, A.M.

    2015-01-01

    Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

  17. The reliability of structural systems operating at high temperature: Replacing engineering judgement with operational experience

    Chevalier, M.J.; Smith, D.J.; Dean, D.W.

    2012-01-01

    Deterministic assessments are used to assess the integrity of structural systems operating at high temperature by providing a lower bound lifetime prediction, requiring considerable engineering judgement. However such a result may not satisfy the structural integrity assessment purpose if the results are overly conservative or conversely plant observations (such as failures) could undermine the assessment result if observed before the lower bound lifetime. This paper develops a reliability methodology for high temperature assessments and illustrates the impact and importance of managing the uncertainties within such an analysis. This is done by separating uncertainties into three classifications; aleatory uncertainty, quantifiable epistemic uncertainty and unquantifiable epistemic uncertainty. The result is a reliability model that can predict the behaviour of a structural system based upon plant observations, including failure and survival data. This can be used to reduce the over reliance upon engineering judgement which is prevalent in deterministic assessments. Highlights: ► Deterministic assessments are shown to be heavily reliant upon engineering judgment. ► Based upon the R5 procedure, a reliability model for a structural system is developed. ► Variables must be classified as either aleatory or epistemic to model their impact on reliability. ► Operation experience is then used to reduce reliance upon engineering judgment. ► This results in a model which can predict system behaviour and learn from operational experience.

  18. Clinical Education Environment Experiences of Operating Room Students

    Tahereh khazaei

    2016-01-01

    Full Text Available Background and purpose: The objective of medical education is to train competent and qualified workforce in order to provide services in various health environments. One of the important objectives of Operating Room students is to train workforce who can involve in patient’s health and recovery. Training these students should cause clinical ability and independent decision making during surgery. Since students during internship face with many problems, this study has been conducted to explore and describe the challenges and experiences.Methods: This qualitative study is a phenomenology that was conducted based on 20 students in the last semester of Operating Room associate’s degree with purposive sampling. Deep and semi-structured interviews were used to collect data and data were analyzed by content analysis method.Results: The findings in 5 main themes: (1 Physical space and equipment in the operating room, (2 The student’s position in operating room, (3 Integrating knowledge and action, (4 Managing education environment and 5- Student’s viewpoint about operating room and working in it.Conclusions: Interviews with students revealed the educational environment challenges with which they are faced during their study. Teachers can provide solutions to overcome the challenges and create a positive atmosphere for students' learning using results of this study and students may continue their interest in education and improve the quality of their education.Keywords: CLINICAL EDUCATION, OPERATING ROOM STUDENTS, CHALLENGE

  19. Operational experience feedback in the World Association of Nuclear Operators (WANO)

    Revuelta, Ramon

    2004-01-01

    Operators in high-risk industries need to be learning organisations, learning from themselves and from the others. This presentation will describe how the nuclear industry is dealing in an integrated manner with the feedback of operating experience (OE), both internal and external, to increase the safety and reliability of power plants; it will describe how it: - investigates events; - reports events and analyses trends; - shares information to prevent recurrence; - performs corrective action and training; - performs assessments to verify effectiveness. The plants have achieved great improvements in performance overall, and to improve further, the industry is evolving. Instead of just learning from past events (reactive) it is now focusing on lower level indications of problems (precursors) through low level events reporting, trending and analysis. A hallmark of the industry is its desire to be self-critical. Emphasis is placed on improving the bottom quartile performing plants

  20. EBO feed water distribution system, experience gained from operation

    Matal, O. [Energovyzkum, Brno (Switzerland); Schmidt, S.; Mihalik, M. [Atomove Elektrarne Bohunice, Jaslovske Bohunice (Switzerland)

    1997-12-31

    Advanced feed water distribution systems of the EBO design have been installed into steam generators at Units 3 and 4 of the NPP Jaslovske Bohunice (VVER 440). Experiences gained from the operation of steam generators with the advanced feed water distribution systems are discussed in the paper. (orig.). 4 refs.

  1. EBO feed water distribution system, experience gained from operation

    Matal, O [Energovyzkum, Brno (Switzerland); Schmidt, S; Mihalik, M [Atomove Elektrarne Bohunice, Jaslovske Bohunice (Switzerland)

    1998-12-31

    Advanced feed water distribution systems of the EBO design have been installed into steam generators at Units 3 and 4 of the NPP Jaslovske Bohunice (VVER 440). Experiences gained from the operation of steam generators with the advanced feed water distribution systems are discussed in the paper. (orig.). 4 refs.

  2. Operating experience and corrective action program at Ontario Hydro Nuclear

    Collingwood, Barry; Turner, David

    1998-01-01

    This is a slide-based talk given at the COG/IAEA: 5. Technical Committee Meeting on 'Exchange of operating experience of pressurized heavy water reactors'. In the introduction there are presented the operating experience (OPEX) program of OHN, and the OPEX Program Mission, ensuring that the right information gets to the right staff at the right time. The OPEX Processes are analysed. These are: - Internal Corrective Action; - Inter-site Lesson Transfer; - External Lesson Transfer; - External Posting of OHN Events; - Internalizing Operating Experience. Steps in solving the Corrective Action Program are described: - Identify the Problem; - Notify Immediate Supervision/Manager; - Evaluate the Problem; - Correct the Problem; Monitor/Report Status. The Internal Corrective Action is then presented as a flowchart. The internalizing operating experience is presented under three aspects: - Communication; - Interface; - Training. The following items are discussed, respectively: peer meetings, department/section meetings, safety meetings, e-mail folders, newsletters and bulletin boards; work planning, pre-job briefings, supervisors' briefing cards; classroom initial and refresher (case studies), simulator, management courses. A diagram is presented showing the flow and treatment of information within OHN, centered on the weekly screening meetings. Finally, the corrective action processes are depicted in a flowchart and analysed in details

  3. Operating Experience with Power Reactors. Proceedings of the Conference on Operating Experience with Power Reactors. Vol. I

    NONE

    1963-10-15

    At the beginning of 1963 nuclear power plants produced some 3 500 000kW of electrical power to different distribution grids around the world. Much significant operating experience has been gained with these power reactors, but this experience is often not collected in such a way as to make it easily available. The International Atomic Energy Agency convened a Conference on Operating Experience with Power Reactors in Vienna from 4-8 June 1963 which was attended by 240 participants representing 27 of the Agency's Member States and six international organizations. At the Conference, 42 papers giving detailed experience with more than 20 nuclear power stations were discussed. Although similar meetings on a national or regional scale have been held earlier in various countries, this is the first arranged by the Agency on a world-wide basis. Some of the detailed material may have been given earlier but for the most part it represents new and recently acquired experience, and for the first time it has been possible to compile in one place such extensive material on the operating experience with power reactors. The Conference discussed the experience gained both generally in the context of national and international nuclear power development programmes, and more specifically in the detailed operating experience with different power reactor stations. In addition, various plant components, fuel cycles, staffing of nuclear plants and licensing of such staff were treated. It is hoped that these Proceedings will be of interest not only to nuclear plant designers and operators who daily encounter problems similar to those discussed by the Conference, but also to those guiding the planning and implementation of power development programmes.

  4. Operating Experience with Power Reactors. Proceedings of the Conference on Operating Experience with Power Reactors. Vol. II

    NONE

    1963-10-15

    At the beginning of 1963 nuclear power plants produced some 3 500 000 kW of electrical power to different distribution grids around the world. Much significant operating experience has been gained with these power reactors, but this experience is often not collected in such a way as to make it easily available. The International Atomic Energy Agency convened a Conference on Operating Experience with Power Reactors in Vienna from 4 -8 June 1963 which was attended by 240 participants representing 27 of the Agency's Member States and six international organizations. At the Conference, 42 papers giving detailed experience with more than 20 nuclear power stations were discussed. Although similar meetings on a national or regional scale have been held earlier in various countries, this is the first arranged by the Agency on a world-wide basis. Some of the detailed material may have been given earlier but for the most part it represents new and recently acquired experience, and for the first time it has been possible to compile in one place such extensive material on the operating experience with power reactors. The Conference discussed the experience gained both generally in the context of national and international nuclear power development programmes, and more specifically in the detailed operating experience with different power reactor stations. In addition, various plant components, fuel cycles, staffing of nuclear plants and licensing of such staff were treated. It is hoped that these Proceedings will be of interest not only to nuclear , plant designers and operators who daily encounter problems similar to those discussed by the Conference, but also to those guiding the planning and implementation of power development programmes.

  5. Experiences on operation, maintenance and utilization in JRR-2

    1994-08-01

    The Japan Research Reactor No.2 (JRR-2) is a high performance 10 MW multi purpose research reactor, heavy water moderated and cooled enriched uranium fuel used. Since the first criticality was attained in October, 1960, JRR-2 has been operated to satisfy the utilization demands, such as irradiation of fuel and materials, neutron beam experiments, radio isotope production and B.N.C.T (Boron Neutron Capture Therapy). During the operation, various kinds of troubles mainly caused by the old design concept had been occurred at the JRR-2 systems and components. Those troubles were solved with adequate countermeasures of timely repairs and large scale modifications with newest techniques. The works above were completely carried out by the staff of JRR-2 and related divisions. As a result, JRR-2 became one of the oldest research reactors which are still under operation in the world. Since JRR-2 has been utilized for more than 30 years, the operation mode was changed from 12 days-one cycle to 3 days-one cycle in April, 1994, taking into consideration aging of the reactor systems. In this paper, the experiences of JRR-2 for more than 30 years such as operation, maintenance, repair, modifications and utilization on JRR-2 are described. (author)

  6. Applying operating experience to design the CANDU 3 process

    Harris, D.S.; Hinchley, E.M.; Pauksens, J.; Snell, V.; Yu, S.K.W.

    1991-01-01

    The CANDU 3 is an advanced, smaller (450 MWe), standardized version of the CANDU now being designed for service later in the decade and beyond. The design of this evolutionary nuclear power plant has been carefully planned and organized to gain maximum benefits from new technologies and from world experience to date in designing, building, commissioning and operating nuclear power stations. The good performance record of existing CANDU reactors makes consideration of operating experience from these plants a particularly vital component of the design process. Since the completion of the first four CANDU 6 stations in the early 1980s, and with the continuing evolution of the multi-unit CANDU station designs since then, AECL CANDU has devised several processes to ensure that such feedback is made available to designers. An important step was made in 1986 when a task force was set up to review and process ideas arising from the commissioning and early operation of the CANDU 6 reactors which were, by that time, operating successfully in Argentina and Korea, as well as the Canadian provinces of Quebec and New Brunswick. The task force issued a comprehensive report which, although aimed at the design of an improved CANDU 6 station, was made available to the CANDU 3 team. By that time also, the Institute of Power Operations (INPO) in the U.S., of which AECL is a Supplier Participant member, was starting to publish Good Practices and Guidelines related to the review and the use of operating experiences. In addition, details of significant events were being made available via the INPO SEE-IN (Significant Event Evaluation and Information Network) Program, and subsequently the CANNET network of the CANDU Owners' Group (COG). Systematic review was thus possible by designers of operations reports, significant event reports, and related documents in a continuing program of design improvement. Another method of incorporating operations feedback is to involve experienced utility

  7. Applying operating experience to design the CANDU 3 process

    Harris, D S; Hinchley, E M; Pauksens, J; Snell, V; Yu, S K.W. [AECL-CANDU, Ontario (Canada)

    1991-04-01

    The CANDU 3 is an advanced, smaller (450 MWe), standardized version of the CANDU now being designed for service later in the decade and beyond. The design of this evolutionary nuclear power plant has been carefully planned and organized to gain maximum benefits from new technologies and from world experience to date in designing, building, commissioning and operating nuclear power stations. The good performance record of existing CANDU reactors makes consideration of operating experience from these plants a particularly vital component of the design process. Since the completion of the first four CANDU 6 stations in the early 1980s, and with the continuing evolution of the multi-unit CANDU station designs since then, AECL CANDU has devised several processes to ensure that such feedback is made available to designers. An important step was made in 1986 when a task force was set up to review and process ideas arising from the commissioning and early operation of the CANDU 6 reactors which were, by that time, operating successfully in Argentina and Korea, as well as the Canadian provinces of Quebec and New Brunswick. The task force issued a comprehensive report which, although aimed at the design of an improved CANDU 6 station, was made available to the CANDU 3 team. By that time also, the Institute of Power Operations (INPO) in the U.S., of which AECL is a Supplier Participant member, was starting to publish Good Practices and Guidelines related to the review and the use of operating experiences. In addition, details of significant events were being made available via the INPO SEE-IN (Significant Event Evaluation and Information Network) Program, and subsequently the CANNET network of the CANDU Owners' Group (COG). Systematic review was thus possible by designers of operations reports, significant event reports, and related documents in a continuing program of design improvement. Another method of incorporating operations feedback is to involve experienced utility

  8. Vitrification operational experiences and lessons learned at the WVDP

    Hamel, W.F. Jr.; Sheridan, M.J.; Valenti, P.J.

    1997-01-01

    The Vitrification Facility (VF) at the West Valley Demonstration Project (WVDP) commenced full, high-level radioactive waste (HLW) processing activities in July 1996. The HLW consists of a blend of washed plutonium-uranium extraction (PUREX) sludge, neutralized thorium extraction (THOREX) waste, and cesium-loaded zeolite. The waste product is borosilicate glass contained in stainless steel canisters, sealed for eventual disposal in a federal repository. This paper discusses the WVDP vitrification process, focusing on operational experience and lessons learned during the first year of continuous, remote operation

  9. Procedure for following external nuclear power plant operating experience

    Kostadinov, V.

    2003-01-01

    Slovenian Nuclear Safety Administration (SNSA) has developed computer database and the procedure for following-up and investigating external nuclear operating experience and administrative requirements. The SNSA's primary goal is to investigate safety significant events in due time, to analyze them from the regulatory point of view and to ensure that meaningful lessons be learned and used for improvement of the safe operation of Slovenian Nuclear Power Plant Krsko. Moreover, we intend to make uniform format and method for reporting broader spectrum of events analyzed including low level event reporting. (author)

  10. Operational experience of ATLAS SCT and Pixel Detector

    Kocian, Martin; The ATLAS collaboration

    2017-01-01

    The ATLAS Inner Detector based on silicon sensors is consisting of a strip detector (SCT) and a pixel detector. It is the crucial component for vertexing and tracking in the ATLAS experiment. With the excellent performance of the LHC well beyond the original specification the silicon tracking detectors are facing substantial challenges in terms of data acquisition, radiation damage to the sensors, and SEUs in the readout ASICs. The approaches on how the detector systems cope with the demands of high luminosity operation while maintaining excellent performance through hardware upgrades, software and firmware algorithms, and operational settings, are presented.

  11. Nuclear power plant operating experience. Annual report, 1978

    Beebe, M.R.

    1979-12-01

    This report is the fifth in a series of reports issued annually that summarizes the operating experience of US nuclear power plants in commercial operation. Power generation statistics, plant outages, reportable occurrences, fuel element performance, occupational radiation exposure for each plant are presented. Summary highlights of these areas are discussed. The report includes 1978 data from 65 plants - 25 boiling water reactor plants and 40 pressurized water reactor plants. Discussion of radioactive effluents which has been a part of this report in previous years, has not been included in this issue because of late acquisition of data

  12. Analysis of operating experience of nuclear power plants

    Volta, G.; Amesz, J.; Mancini, G.

    1981-01-01

    The power reactors operating experience has been matter for studies at the Joint Research Centre of the C.E.C. with the aim of validating probabilistic analysis models and of setting up data banks concerning reliability, availability of components and systems and safety related events. The report shows problems encountered and solutions given to attain the goal. For what concerns validation, the need of more satisfactory models that could handle both the technical and the organizational aspects of an operating plant is shown. For what concerns the data banks the possibilities opened by a coherent international system of classification are underlined. (author)

  13. European clearinghouse on nuclear power plants operational experience feedback

    Ranguelova, Vesselina; Bruynooghe, Christiane; Noel, Marc

    2010-01-01

    Learning from operational experience and applying this knowledge promptly and intelligently is one of the ways to improve the safety of Nuclear Power Plant (NPP). Recent reviews of the effectiveness of Operational Experience Feedback (OEF) systems have pointed to the need for further improvement, with importance being placed on tailoring the information to the needs of the regulators. In 2007, at the request of a number of nuclear safety regulatory authorities in Europe, the Institute for Energy of the European Commission's Joint Research Centre (EC JRC) initiated a project on Nuclear Power Plant operational experience feedback, which adopts an integrated approach to the research needed to strengthen the European capabilities for assessment of NPP operational events and to promote the development of tools and mechanisms for the improved application of the lessons learned. Consequently, a so-called ''European Clearinghouse'' on NPP OEF was established, which includes scientific officers from the EC JRC, a number of European nuclear safety regulatory authorities and some of their Technical Support Organizations (TSOs). The paper discusses the activities implemented in 2008 within the framework of the European Clearinghouse on NPP OEF (hereinafter called the European NPP Clearinghouse) and provides an overview of the main conclusions drawn from the safety studies performed. Outlook of the activities carried out in 2009 are given. (orig.)

  14. Operating experience and radiation protection in RAPS-3 and 4 operations

    Khandelwal, Narendra; Dhakar, P.C.; Singh, G.K.; Gupta, Ashok

    2008-01-01

    Rajasthan Atomic Power Station (RAPS)-3 and 4 was designed and constructed using latest technological advancements in the field of nuclear energy. Operating experience of the station have taught many lessons and provided opportunities to take proactive corrective actions. Design modifications, effective implementation of radiological surveillance program and improvements in work culture have helped in achieving continual reduction in radiation exposures and effluent releases at the station. This paper discusses some of the modifications carried out at the station along with their radiological impacts. (author)

  15. Vacuum system operating experience review for fusion applications

    Cadwallader, L.C.

    1994-03-01

    This report presents a review of vacuum system operating experiences from particle accelerator, fusion experiment, space simulation chamber, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of vacuum system component failure rates and accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with vacuum systems are discussed, including personnel safety, foreign material intrusion, and factors relevant to vacuum systems being the primary confinement boundary for tritium and activated dusts. This information should be useful to fusion system designers and safety analysts, such as the team working on the Engineering Design Activities for the International Thermonuclear Experimental Reactor

  16. TSTA piping and flame arrestor operating experience data

    Cadwallader, Lee C., E-mail: Lee.Cadwallader@inl.gov [Idaho National Laboratory, Idaho Falls, ID (United States); Willms, R. Scott [ITER International Organization, Cadarache (France)

    2015-10-15

    Highlights: • Experiences from the Tritium Systems Test Assembly were examined. • Failure rates of copper piping and a flame arrestor were calculated. • The calculated failure rates compared well to similar data from the literature. • Tritium component failure rate data support fusion safety assessment. - Abstract: The Tritium Systems Test Assembly (TSTA) was a facility dedicated to tritium handling technology and experiment research at the Los Alamos National Laboratory. The facility was operated with tritium for its research and development program from 1984 to 2001, running a prototype fusion fuel processing loop with ∼100 g of tritium as well as small experiments. There have been several operating experience reports written on this facility's operation and maintenance experience. This paper describes reliability analysis of two additional components from TSTA, small diameter copper gas piping that handled tritium in a nitrogen carrier gas, and the flame arrestor used in this piping system. The component failure rates for these components are discussed in this paper. Comparison data from other applications are also presented.

  17. Evaluation of operating experience for service life of components

    Schulz, H.; Sunder, R.

    1987-01-01

    The evaluation of the operating experience of German light-water reactor components based on licensee event reports indicates that a large part of the defects and failures are caused by fatigue and/or corrosion type mechanisms. Actions have been taken to eliminate the causes by redesigning systems, replacement of components and change of operating procedures. The interaction of fatigue and corrosion mechanisms are not understood in all details today, further research is still necessary. To establish a more realistic data base of the local loading and water chemistry condition for all loading conditions the application of advanced monitoring systems is proposed. The benefits of these systems are that the operating procedures can be further optimized, the actual used life time fraction can be calculated regularly and the data base can be used for life time extension. (orig.) [de

  18. Operational experience gained from the Central Brae subsea field

    Sapp, S.J.; Gomersall, S.D.

    1994-01-01

    The size of the field discoveries made in the North Sea in recent years has declined dramatically. With the low oil price many small fields are not viable stand alone developments. The North Sea has a large, well developed infrastructure of production facilities and pipelines. With many platforms now operating below optimum production rate, subsea tieback of these small fields utilizing the available processing capacity is the most economically attractive means of development. This paper presents a history of such a field development. The Central Brae field is located within the Brae complex of fields, 155 miles north east of Aberdeen, and has been developed by means of a subsea facility tied back to the Brae Alpha platform. A great deal of experience has been gained through the field development, not only in subsea operations but also in completion and template design and operating philosophy

  19. Operational Experience with the ATLAS Pixel Detector at the LHC

    Keil, M; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including calibration procedures, timing optimization and detector performance. The detector performance is excellent: ~96 % of the pixels are operational, noise occupancy and hit efficiency e...

  20. Wabash River coal gasification repowering project -- first year operation experience

    Troxclair, E.J. [Destec Energy, Inc., Houston, TX (United States); Stultz, J. [PSI Energy, Inc., West Terre Haute, IN (United States)

    1997-12-31

    The Wabash River Coal Gasification Repowering Project (WRCGRP), a joint venture between Destec Energy, Inc. and PSI Energy, Inc., began commercial operation in November of 1995. The Project, selected by the United States Department of Energy (DOE) under the Clean Coal Program (Round IV) represents the largest operating coal gasification combined cycle plant in the world. This Demonstration Project has allowed PSI Energy to repower a 1950`s vintage steam turbine and install a new syngas fired combustion turbine to provide 262 MW (net) of electricity in a clean, efficient manner in a commercial utility setting while utilizing locally mined high sulfur Indiana bituminous coal. In doing so, the Project is also demonstrating some novel technology while advancing the commercialization of integrated coal gasification combined cycle technology. This paper discusses the first year operation experience of the Wabash Project, focusing on the progress towards achievement of the demonstration objectives.

  1. Experience with dose limitation during preparations for sea dumping operations

    Fieuw, G.; Voorde, N. van de; Baekelandt, L.

    1982-01-01

    Since 1967 low-level radioactive wastes from operational nuclear facilities in Belgium have been dumped into the sea. The dumping is carried out in accordance with the recommendations issued by the IAEA under the London Convention. All these dumping operations have taken place under the surveillance of the Nuclear Energy Agency of the OECD. To limit the doses received by workers and the public during the various phases leading up to sea dumping, appropriate measures are required in connection with waste treatment and packaging, limitation of radiation levels, storage and handling, organization and selection of the means of transport and organization and means of monitoring. Although treatment and handling at the nuclear sites are entrusted to occupationally exposed workers, temporary labour is used for the transport and handling operations. Effective treatment and packaging reduce the risk of internal exposure to a negligible value. Meticulous planning and permanent personnel monitoring reduce the doses received by the workers to acceptable values not exceeding the statutory dose limits. The doses received by personnel involved in the preparations for sea dumping operations from 1967 to 1980 are given and a relationship is established between these doses and the activities handled. Experience shows that sea dumping operations do not entail unacceptable risks either for the workers concerned or for the population and allows us to optimize the methods used for loading, handling and transport. (author)

  2. Operating experience and procedures at the tritium systems test assembly

    Carlson, R.V.; Binning, K.E.; Cole, S.P.; Jenkins, E.M.; Wilhelm, R.C.; Cole, S.P.

    1988-01-01

    Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig

  3. The National Flood Interoperability Experiment: Bridging Resesarch and Operations

    Salas, F. R.

    2015-12-01

    The National Weather Service's new National Water Center, located on the University of Alabama campus in Tuscaloosa, will become the nation's hub for comprehensive water resources forecasting. In conjunction with its federal partners the US Geological Survey, Army Corps of Engineers and Federal Emergency Management Agency, the National Weather Service will operationally support both short term flood prediction and long term seasonal forecasting of water resource conditions. By summer 2016, the National Water Center will begin evaluating four streamflow data products at the scale of the NHDPlus river reaches (approximately 2.67 million). In preparation for the release of these products, from September 2014 to August 2015, the National Weather Service partnered with the Consortium of Universities for the Advancement of Hydrologic Science, Inc. to support the National Flood Interoperability Experiment which included a seven week in-residence Summer Institute in Tuscaloosa for university students interested in learning about operational hydrology and flood forecasting. As part of the experiment, 15 hour forecasts from the operational High Resolution Rapid Refresh atmospheric model were used to drive a three kilometer Noah-MP land surface model loosely coupled to a RAPID river routing model operating on the NHDPlus dataset. This workflow was run every three hours during the Summer Institute and the results were made available to those engaged to pursue a range of research topics focused on flood forecasting (e.g. reservoir operations, ensemble forecasting, probabilistic flood inundation mapping, rainfall product evaluation etc.) Although the National Flood Interoperability Experiment was finite in length, it provided a platform through which the academic community could engage federal agencies and vice versa to narrow the gap between research and operations and demonstrate how state of the art research infrastructure, models, services, datasets etc. could be utilized

  4. Estimation of fire frequency from PWR operating experience

    Bertrand, R.; Bonneval, F.; Barrachin, G.; Bonino, F.

    1998-01-01

    In the framework of a fire probabilistic safety assessment (Fire PSA), the French Institute for Nuclear Safety and Protection (IPSN) has developed a method for estimating the frequency of fire in a nuclear power plant room. This method is based on the analysis of French Pressurized Water Reactors operating experience. The method adopted consists is carrying out an in-depth analysis of fire-related incidents. A database has been created including 202 fire events reported in 900 MWe and 1300 MWe reactors from the start of their commercial operation up to the first of March 1994, which represents a cumulated service life of 508 reactor-years. For each reported fire, several data were recorded among which: The operating state of the reactor in the stage preceding the fire, the building in which the fire broke out, the piece of equipment or the human intervention which caused the fire. Operating experience shows that most fires are initiated by electrical problems (short-circuits, arcing, faulty contacts, etc.) and that human intervention also plays an important role (grinding, cutting, welding, cleaning, etc.). A list of equipment and of human interventions which proved to be possible fire sources was therefore drawn up. the items of this list were distributed in 19 reference groups defined by taking into account the nature of the potential ignition source (transformers, electrical cabinets, pumps, fans, etc.). The fire frequency assigned to each reference group was figured out using the operating experience information of the database. The fire frequency in a room is considered to be made out of two contributions: one due to equipment which is proportional to the number of pieces of equipment from each reference group contained in the room, and a second one which is due to human interventions and assumed to be uniform throughout the reactor. Formulas to assess the fire frequencies in a room, the reactor being in a shutdown state or at power, are then proposed

  5. Operating Experience at the Aagesta Nuclear Power Station

    Sandstroem, S.

    1966-09-01

    Sweden's first nuclear power reactor Agesta, achieved criticality on July 17, 1963. Full power (65 MW t ) was attained on March 20, 1964. Aagesta is a heavy water cooled and moderated pressure vessel reactor used for production of electricity as well as for district heating. The design, assembly and construction etc, of the reactor was described in detail in a staff report by AB Atomenergi, 'The Aagesta Nuclear Power Station' edited by B McHugh, which was published in September, 1964. In the book experiences from the commissioning and the first operation of the reactor were reported as well as findings from the extensive reactor physics studies made during this period. The report now presented is written by members of the operating team at Aagesta since its start. It reflects in general the experiences up to the end of 1965. The Aagesta Log, however, covers the period up to the normal summer stop 1966. The reactor has hitherto produced 506,000 MWh power of which 48,700 MWh have been electric power. In July 1965 the responsibility for the reactor operation was taken over by the Swedish State Power Board from AB Atomenergi, which company had started the reactor and operated it until the summer break 1965

  6. Operating Experience at the Aagesta Nuclear Power Station

    Sandstroem, S [ed.

    1966-09-15

    Sweden's first nuclear power reactor Agesta, achieved criticality on July 17, 1963. Full power (65 MW{sub t}) was attained on March 20, 1964. Aagesta is a heavy water cooled and moderated pressure vessel reactor used for production of electricity as well as for district heating. The design, assembly and construction etc, of the reactor was described in detail in a staff report by AB Atomenergi, 'The Aagesta Nuclear Power Station' edited by B McHugh, which was published in September, 1964. In the book experiences from the commissioning and the first operation of the reactor were reported as well as findings from the extensive reactor physics studies made during this period. The report now presented is written by members of the operating team at Aagesta since its start. It reflects in general the experiences up to the end of 1965. The Aagesta Log, however, covers the period up to the normal summer stop 1966. The reactor has hitherto produced 506,000 MWh power of which 48,700 MWh have been electric power. In July 1965 the responsibility for the reactor operation was taken over by the Swedish State Power Board from AB Atomenergi, which company had started the reactor and operated it until the summer break 1965.

  7. Canadian fuel development program and recent operational experience

    Cox, D.S.; Kohn, E.; Lau, J.H.K.; Dicke, G.J.; Macici, N.N.; Sancton, R.W.

    1995-01-01

    This paper provides an overview of the current Canadian CANDU fuel R and D programs and operational experience. The details of operational experience for fuel in Canadian reactors are summarized for the period 1991-1994; excellent fuel performance has been sustained, with steady-state bundle defect rates currently as low as 0.02%. The status of introducing long 37-element bundles, and bundles with rounded bearing pads is reviewed. These minor changes in fuel design have been selectively introduced in response to operational constraints (end-plate cracking and pressure-tube fretting) at Ontario Hydro's Bruce-B and Darlington stations. The R and D programs are generating a more complete understanding of CANDU fuel behaviour, while the CANDU Owners Group (COG) Fuel Technology Program is being re-aligned to a more exclusive focus on the needs of operating stations. Technical highlights and realized benefits from the COG program are summarized. Re-organization of AECL to provide a one-company focus, with an outward looking view to new CANDU markets, has strengthened R and D in advanced fuel cycles. Progress in AECL's key fuel cycle programs is also summarized. (author)

  8. Operating Experience at the Aagesta Nuclear Power Station

    Sandstroem, S. (ed.)

    1966-09-15

    Sweden's first nuclear power reactor Agesta, achieved criticality on July 17, 1963. Full power (65 MW{sub t}) was attained on March 20, 1964. Aagesta is a heavy water cooled and moderated pressure vessel reactor used for production of electricity as well as for district heating. The design, assembly and construction etc, of the reactor was described in detail in a staff report by AB Atomenergi, 'The Aagesta Nuclear Power Station' edited by B McHugh, which was published in September, 1964. In the book experiences from the commissioning and the first operation of the reactor were reported as well as findings from the extensive reactor physics studies made during this period. The report now presented is written by members of the operating team at Aagesta since its start. It reflects in general the experiences up to the end of 1965. The Aagesta Log, however, covers the period up to the normal summer stop 1966. The reactor has hitherto produced 506,000 MWh power of which 48,700 MWh have been electric power. In July 1965 the responsibility for the reactor operation was taken over by the Swedish State Power Board from AB Atomenergi, which company had started the reactor and operated it until the summer break 1965.

  9. Safety aspects and operating experience of LWR plants in Japan

    Aoki, S.; Yoshioka, T.; Toyota, M.; Hinoki, M.

    1977-01-01

    To develop nuclear power generation for the future, it is necessary to put further emphasis on safety assurance and to endeavour to devise measures to improve plant availability, based on the careful analysis of causes that reduce plant availability. The paper discusses the results of studies on the following items from such viewpoints: (1) Safety and operating experience of LWR nuclear power plants in Japan: operating experience with LWRs; improvements in LWR design during the past ten years; analysis of the factors affecting plant availability; (2) Assurance of safety and measures to increase availability: measures for safety and environmental protection; measures to reduce radiation exposure of employees; appropriateness of maintenance and inspection work; measures to increase plant availability; measures to improve reliability of equipment and components; (3) Future technical problems. (author)

  10. ATLAS Operations: Experience and Evolution in the Data Taking Era

    Ueda, I; The ATLAS collaboration; Goossens, L; Stewart, G; Jezequel, S; Nairz, A; Negri, G; Campana, S; Di Girolamo, A

    2011-01-01

    This paper summarises the operational experience and improvements of the ATLAS hierarchical multi-tier computing infrastructure in the past year leading to taking and processing of the first collisions in 2009 and 2010. Special focus will be given to Tier-0 which is responsible, among other things, for a prompt processing of the raw data coming from the online DAQ system and is thus critical part of the chain. We will give an overview of the Tier-0 architecture, and improvements based on the operational experience. Emphasis will be put on the new developments, namely the Task Management System opening Tier-0 to expert users and Web 2.0 monitoring and management suite. We then overview the achieved performances with the distributed computing system, discuss observed data access patterns over the grid and describe how we used this information to improve analysis rates.

  11. Operating Experiences of a Loss of Voltage Monitoring Program

    Lee, Eun-Chan [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2015-10-15

    Loss of voltage (LOV) events continue to occur due to inadequate work management and random human errors. On February 26, 2015, regulators analyzed the root causes of LOV events and presented the results for the nuclear industry. Currently, KHNP uses a risk monitoring program, which is named 'LOV Monitor', for LOV prevention during pilot plant outages. This review introduces the operation experiences of LOV Monitor based on the evaluation results of a real event. The operation experiences of LOV Monitor in the pilot plants confirmed that this program could detect and reduce LOV possibilities from scheduling errors such as the simultaneous maintenance of energized trains and de-energized trains considering the physical conditions of the power circuit breakers. However, a maintenance culture that heeds the risk monitoring result must be strengthened in order to obtain substantial effects through applying LOV Monitor to the outage.

  12. ATLAS Operations: Experience and Evolution in the Data Taking Era

    Ueda, I

    2011-01-01

    This paper summarises the operational experience and improvements of the ATLAS hierarchical multi-tier computing infrastructure in the past year leading to taking and processing of the first collisions in 2009 and 2010. Special focus will be given to the Tier-0 which is responsible, among other things, for a prompt processing of the raw data coming from the online DAQ system and is thus a critical part of the chain. We will give an overview of the Tier-0 architecture, and improvements based on the operational experience. Emphasis will be put on the new developments, namely the Task Management System opening Tier-0 to expert users and Web 2.0 monitoring and management suite. We then overview the achieved performances with the distributed computing system, discuss observed data access patterns over the grid and describe how we used this information to improve analysis rates.

  13. Machine utilisation and operation experience with Jet from 1983

    Green, B.J.; Chuilon, P.; Noble, B.; Saunders, R.; Webberley, D.

    1989-01-01

    The operation of JET commenced in June 1983 and is scheduled until the end of 1992. This seemingly long period is actually quite limited when compared with the time needed to implement and commission the planned machine enhancements, and pursue research and developments which result from the experiments. There is an ever-present urgency to make the best use of the machine. 1983-84 was a learning period and only in 1985 was it felt worthwhile to adopt double-shift day working. Data has been compiled and analysed for utilisation of the machine, delays in terms of time lost and systems involved, and number and frequency of machine pulses. This paper presents an overall picture of machine availability and utilisation. It describes the JET operational arrangements and the experience of system faults. Finally, it draws conclusions and identifies lessons learned which may be relevant to the next stage of fusion power development

  14. Machine utilisation and operation experience with JET from 1983

    Green, B.J.; Chuilon, P.; Noble, B.; Saunders, R.; Webberley, D.

    1989-01-01

    The operation of JET commenced in June 1983 and is scheduled until the end of 1992. This seemingly long period is actually quite limited when compared with the time needed to implement and commission the planned machine enhancements, and pursue research and developments which result from the experiments. There is an ever-present urgency to make the use of the machine. 1983-84 was a learning period and only in 1985 was it felt worthwhile to adopt double-shift day working. Data has been compiled and analysed for utilisation of the machine, delays in terms of time lost and system involved, and number and frequency of machine pulses. This paper presents an overall picture of machine availability and utilisation. It describes the JET operational arrangements and the experience of system faults. Finally, it draws conclusions and identifies lessons learned which may be relevant to the next stage of fusion power development. (author). 9 figs

  15. Laparoscopic myotomy in achalasia cardia treatment: Experience after 36 operations

    Bjelović Miloš

    2013-01-01

    Full Text Available Introduction. Laparoscopic Heller­Dor operation, a standard method in the treatment of achalasia, has been performed at the Center for Esophageal Surgery of the First Surgical Clinic since April 2006. Objective. The aim of this study was to present this surgical procedure and initial experiences after 36 consecutive laparoscopic Heller­Dor operations. Methods. This partly retrospective, partly prospective study presented our results after laparoscopic Heller­Dor operation (presentation of the treatment method. We performed a standard anterior esophagocardioymiotomy, without releasing the posterior aspect of the cardia, and anterior partial fundoplication. The type and severity of symptoms and their duration were evaluated based on questionnaires fulfilled by patients. The diagnosis was made based on radiological, endoscopic and manometric findings. Laparoscopic surgery as the method of treatment was evaluated based on the duration of surgery, intra­ and postoperative complications, time interval until the initiation of oral feeding, length of hospital stay, need for additional therapeutic measures after the operation and effect of surgery on the severity of symptoms. Results. Preopereratively, dysphagia was the predominant symptom in all patients, while regurgitation was much lower (44%. The average duration of operation was 127 minutes. Postoperative hospitalization lasted on the average 5.7 days. From 36 treated patients, 34 (94.4% considered that the effect of treatment was good or excellent. Postoperative dysphagia was present in two patients (5.6% and was successfully solved by balloon dilatation. Conclusion. Laparoscopic Heller­Dor operation is an effective and safe surgical procedure in resolving symptoms of achalasia and today presents the method of the first choice in the treatment of this disease.

  16. Research on the NPP human factors engineering operating experience review

    Ren Xiangchen; Miao Hongxing; Ning Zhonghe

    2006-01-01

    This paper addresses the importance of the human factors engineering (HFE) for the design of nuclear power plant (NPP), especially for the design of human-machine interface in the NPP. It also summarizes the scope and content of the NPP HFE. The function, scope, content and process of the NPP human factors engineering operating experience review (OER) are mainly focused on, and significantly discussed. Finally, it briefly introduces the situation of the studies on the OER in China. (authors)

  17. Experience building and operating the CMS Tier-1 computing centres

    Albert, M.; Bakken, J.; Bonacorsi, D.; Brew, C.; Charlot, C.; Huang, Chih-Hao; Colling, D.; Dumitrescu, C.; Fagan, D.; Fassi, F.; Fisk, I.; Flix, J.; Giacchetti, L.; Gomez-Ceballos, G.; Gowdy, S.; Grandi, C.; Gutsche, O.; Hahn, K.; Holzman, B.; Jackson, J.; Kreuzer, P.; Kuo, C. M.; Mason, D.; Pukhaeva, N.; Qin, G.; Quast, G.; Rossman, P.; Sartirana, A.; Scheurer, A.; Schott, G.; Shih, J.; Tader, P.; Thompson, R.; Tiradani, A.; Trunov, A.

    2010-04-01

    The CMS Collaboration relies on 7 globally distributed Tier-1 computing centres located at large universities and national laboratories for a second custodial copy of the CMS RAW data and primary copy of the simulated data, data serving capacity to Tier-2 centres for analysis, and the bulk of the reprocessing and event selection capacity in the experiment. The Tier-1 sites have a challenging role in CMS because they are expected to ingest and archive data from both CERN and regional Tier-2 centres, while they export data to a global mesh of Tier-2s at rates comparable to the raw export data rate from CERN. The combined capacity of the Tier-1 centres is more than twice the resources located at CERN and efficiently utilizing this large distributed resources represents a challenge. In this article we will discuss the experience building, operating, and utilizing the CMS Tier-1 computing centres. We will summarize the facility challenges at the Tier-1s including the stable operations of CMS services, the ability to scale to large numbers of processing requests and large volumes of data, and the ability to provide custodial storage and high performance data serving. We will also present the operations experience utilizing the distributed Tier-1 centres from a distance: transferring data, submitting data serving requests, and submitting batch processing requests.

  18. Experience building and operating the CMS Tier-1 computing centres

    Albert, M; Bakken, J; Huang, Chih-Hao; Dumitrescu, C; Fagan, D; Fisk, I; Giacchetti, L; Gutsche, O; Holzman, B; Bonacorsi, D; Grandi, C; Brew, C; Jackson, J; Charlot, C; Colling, D; Fassi, F; Flix, J; Gomez-Ceballos, G; Hahn, K; Gowdy, S

    2010-01-01

    The CMS Collaboration relies on 7 globally distributed Tier-1 computing centres located at large universities and national laboratories for a second custodial copy of the CMS RAW data and primary copy of the simulated data, data serving capacity to Tier-2 centres for analysis, and the bulk of the reprocessing and event selection capacity in the experiment. The Tier-1 sites have a challenging role in CMS because they are expected to ingest and archive data from both CERN and regional Tier-2 centres, while they export data to a global mesh of Tier-2s at rates comparable to the raw export data rate from CERN. The combined capacity of the Tier-1 centres is more than twice the resources located at CERN and efficiently utilizing this large distributed resources represents a challenge. In this article we will discuss the experience building, operating, and utilizing the CMS Tier-1 computing centres. We will summarize the facility challenges at the Tier-1s including the stable operations of CMS services, the ability to scale to large numbers of processing requests and large volumes of data, and the ability to provide custodial storage and high performance data serving. We will also present the operations experience utilizing the distributed Tier-1 centres from a distance: transferring data, submitting data serving requests, and submitting batch processing requests.

  19. Recent experience of Almaraz NPP in operator training

    Sanchez Cabanero, J.G.; Gomez de la Torre, J.M.

    1994-01-01

    In recent years the nuclear industry has been paying special attention to boosting nuclear power plant operation. To this end, it has optimized its maintenance, engineering, safety, management and other systems, using the appropriate resources to achieve its target. Optimization of these systems required the allocation of new resources for training plant personnel. The activity of training, which hitherto dedicated most of its attention and resources to the operating area, now extends them to schooling required in other areas of the plant, with the aim of updating the skills and knowledge of personnel to deal with new needs which have arisen. Regulations at present cover the training and qualification of only personnel responsible for handling reactor or for directing plant operation activities and capable of evaluating the nature and magnitude of possible incidents, especially those causing radioactive emissions, and of personnel requiring knowledge and experience to guarantee effective protection of individuals, ie, operators, supervisors, and qualified radiological protection experts. However, it should be borne in mind that, in the future, the training of other plant personnel could also be subject to regulations. (Author)

  20. Operating experience and aging-seismic assessment of electric motors

    Subudhi, M.; Burns, E.L.; Taylor, J.H.

    1985-06-01

    Objectives of this program are to identify concerns related to the aging and service wear of equipment operating in nuclear power plants, to assess their possible impact on plant safety, to identify effective inspection surveillance and monitoring methods and to recommend suitable maintenance practices for mitigating aging related concerns and diminish the rate of degradation due to aging and service wear. Motor design and materials of construction are reviewed to identify age-sensitive components. Operational and accidental stressors are determined, and their effect on promoting aging degradation is assessed. Failure modes, mechanisms, and causes have been reviewed from operating experiences and existing data banks. The study has also included consideration for the seismic correlation of age-degraded motor components. The aforementioned reviews and assessments were assimilated to characterize the dielectric, rotational, and mechanical hazards on motor performance and operational readiness. The functional indicators which can be monitored to assess motor component deterioration due to aging or other accidental stressors are identified. Conforming with the NPAR strategy as outlined in the program plan, the study also includes a preliminary discussion of current standards and guides, maintenance programs, and research activities pertaining to nuclear power plant safety-related electric motors

  1. Operational Experience and Performance with the ATLAS Pixel detector

    Martin, Christopher Blake; The ATLAS collaboration

    2018-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of $1.3\\times10^{34}\\text{cm}^{{-2}}\\text{s}^{{-1}}$ recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarized, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  2. Operational Experience and Performance with the ATLAS Pixel detector

    Martin, Christopher Blake; The ATLAS collaboration

    2018-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of 1.3 x 10^34 cm-2 s-1 recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  3. Evolution of PHWR fuel transfer system based on operating experience

    Parvatikar, R.S.; Singh, Jaipal; Chaturvedi, P.C.; Bhambra, H.S.

    2006-01-01

    Fuel Transfer System facilitates loading of new fuel into Fuelling Machine, receipt of spent fuel from Fuelling Machine and its further transportation to Storage Bay. To overcome the limitations of transferring a pair of bundles in the single tube Airlock and Transfer Arm in RAPS-1 and 2/MAPS, a new concept of six tube Transfer Magazine was introduced in NAPS. This resulted in simultaneous loading of new fuel from Transfer Magazine into the Fuelling Machine and unloading of spent fuel from the Fuelling Machine through the exchange mode. It further facilitated the parallel/simultaneous operation of refuelling by Fuelling Machines on the reactor and transferring of spent fuel bundles from the Transfer Magazine to the bay. This new design of Fuel Transfer System was adopted for all standardised 220 MWe PHWRs. Based on the experience gained in 220 MWe PHWRs in the area of operation and maintenance, a number of improvements have been carried out over the years. These aspects have been further strengthened and refined in the Fuel Transfer System of 540 MWe units. The operating experience of the system indicates that the presence of heavy water in the Transfer Magazine poses limitations in its maintenance in the Fuel Transfer room. Further, Surveillance and maintenance of large number of under water equipment and associated valves, rams and underwater sensors is putting extra burden on the O and M efforts. A new concept of mobile light water filled Transfer Machine has been evolved for proposed 700 MWe PHWR units to simplify Fuel Transfer System. This has been made possible by adopting snout level control in the Fuelling Machine, elimination of Shuttle Transport System and locating the Storage Bay adjacent to the Reactor Building. This paper describes the evolution of Fuel Transfer System concepts and various improvements based on the experience gained in the operation and maintenance of the system. (author)

  4. Application of operating experience in environmental qualification program

    Lee, S.Y.; Wise, R.

    2000-01-01

    Environmental qualification (EQ) of equipment related to nuclear safety has been carried out in the nuclear community since the 70's. It started with electrical equipment and then expanded to include mechanical equipment. During this evolutionary process, the methods used for EQ have gone through a long period of refinement and clarification. Prior to 1971, qualification for equipment in licensed nuclear power plants was based on the use of electrical components of commonly accepted high industrial quality without the benefit of specific environmental qualification standards. Between 1971 and 1974, most plants used the criteria of IEEE Standard 323-1971 as the basis for demonstrating qualification. Also during this period related 'daughter' standards, mainly by IEEE, became available which addressed qualification for specific equipment items. After July 1974, plants were required to meet the more comprehensive guidelines specified in IEEE Standard 323-1974 and the related 'daughter' standards. IEEE Standard 323-1974 later evolved into IEEE Standard 323-1983. For nuclear power plants built in Ontario during the 70's, i.e. Pickering B and Bruce B, has included the environmental qualification requirements in their respective nuclear safety design guides. It is now recognized that they are not up to the current EQ standards. Darlington, constructed during the 80's, implemented the environmental qualification program in its project. An Environmental Qualification (EQ) Program is now under way in Ontario Power Generation (OPG) to formally implement the Environmental Qualification for Bruce B, Pickering B, and Pickering A and to preserve the Qualification for Darlington G.S. This paper makes a thorough a review of the standard methods used in the past by utilities for environmental qualification. These methods include type testing, analysis, and operating experience. Both type testing and analysis have been clearly defined in standards listed in References [2] to [6] and

  5. Review of BNFL's operational experience of wet type flasks

    McWilliam, D.S.

    2004-01-01

    BNFL International Transport's operational experience includes shipping 6000te of spent fuel from Japan to Sellafield, through its dedicated terminal at Barrow, and to Cogema La Hague. This fuel was shipped under the PNTL (Pacific Nuclear Transport Ltd) banner for which BNFL is responsible. PNTL owned and operated a fleet of 5 ships for Japanese business and a fleet of 80 wet and 58 dry flasks, for the transport of Light Water Reactor (LWR) spent fuel, from both Pressurised Water Reactors (PWR) and Boiling Water Reactors (BWR). ''Wet'' or ''dry'' flask is the common terminology used to distinguish between spent fuel flasks transporting fuel where the fuel is immersed in water, or spent fuel flasks that have been drained of water and dried. This paper concentrates on the wet type of flask utilised to transport fuel to Sellafield, that is the Excellox type (including similar type NTL derivatives). It aims to provide a summary of operational experience during handling at power stations, shipment, unloading at reprocessors and from scheduled maintenance

  6. Physics operating experience and fuel management of RAPS-1

    Nakra, A.N.; Purandare, H.D.; Srinivasan, K.R.; Rastogi, B.P.

    1976-01-01

    Rajasthan Atomic Power Station Unit-1 achieved criticality on August 11, 1972. Thereafter the reactor was brought to power, in November, 1972. Due to non-availability of the depleted fuel, the loading of which was necessary to obtain full power to begin with, the core was loaded with all natural uranium fuel and only 70% of the full power could be achieved. During the reactor operation for the last three years, the reactor has seen more than one effective full power year and about 1400 fresh fuel bundles have been loaded in the core. The reactor was subjected to about 150 power cycles resulting in more than 30% variation in operating power level and about 10 fuel bundles have failed. For satisfactory fuel management and refuelling decisions, a three dimensional simulator TRIVENI was developed. This was extensively tested during the start-up experiments and was found to be a satisfactory tool for day to day operation of the plant. In this paper, a brief account of analysis of the start-up experiments, approach to full power, power distortions and flux peaking, fuel management service and analysis of the failed fuel data has been given. (author)

  7. Variable Operative Experience in Hand Surgery for Plastic Surgery Residents.

    Silvestre, Jason; Lin, Ines C; Levin, Lawrence Scott; Chang, Benjamin

    Efforts to standardize hand surgery training during plastic surgery residency remain challenging. We analyze the variability of operative hand experience at U.S. plastic surgery residency programs. Operative case logs of chief residents in accredited U.S. plastic surgery residency programs were analyzed (2011-2015). Trends in fold differences of hand surgery case volume between the 10th and 90th percentiles of residents were assessed graphically. Percentile data were used to calculate the number of residents achieving case minimums in hand surgery for 2015. Case logs from 818 plastic surgery residents were analyzed of which a minority were from integrated (35.7%) versus independent/combined (64.3%) residents. Trend analysis of fold differences in case volume demonstrated decreasing variability among procedure categories over time. By 2015, fold differences for hand reconstruction, tendon cases, nerve cases, arthroplasty/arthrodesis, amputation, arterial repair, Dupuytren release, and neoplasm cases were below 10-fold. Congenital deformity cases among independent/combined residents was the sole category that exceeded 10-fold by 2015. Percentile data suggested that approximately 10% of independent/combined residents did not meet case minimums for arterial repair and congenital deformity in 2015. Variable operative experience during plastic surgery residency may limit adequate exposure to hand surgery for certain residents. Future studies should establish empiric case minimums for plastic surgery residents to ensure hand surgery competency upon graduation. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  8. Recent operating experience and improvement of commercial IGCC

    NONE

    2013-09-01

    IGCC has today reached a status where experience is available from first and second generation plants, built in the 1970s/1980s and in the 1990s respectively, as commercial-scale demonstration plants for coal-based applications. These plants feature variations on gasification technology and subsequent environmental controls and in operating them a number of technical and commercial lessons have been learned that will help to improve the next generation of IGCC projects. The report reviews and summarises the state-of-the-art and operating experience of several commercial IGCC plants worldwide, setting out the lessons learned and plans for future development embracing such issues as the changes or modifications to plant made to overcome the operational problems and to improve the reliability and availability of the plant. Since IGCC is considered a 'capture ready' technology for CO2 abatement, the current status with regard to the incorporation of carbon capture and storage systems (CCS) has been reviewed. Finally, the report outlines the issues associated with assessing the risks in commercialising IGCC plant.

  9. Operational Experience with the ATLAS Pixel Detector at the LHC

    Keil, M; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  10. Operational experience with the ATLAS Pixel Detector at the LHC

    Hirschbuehl, D; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.7% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  11. Operational experience with the ATLAS Pixel Detector at the LHC

    Lapoire, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  12. Operational Experience with the ATLAS Pixel Detector at the LHC

    Lapoire, C; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as B-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures and detector performance. The detector performance is excellent: 96.2% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification.

  13. Operational Experience with the ATLAS Pixel Detector at the LHC

    Keil, M

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including calibration procedures, timing optimization and detector performance. The detector performance is excellent: approximately 97% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  14. Operational experience with the ATLAS Pixel Detector at the LHC

    Ince, T; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.8% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  15. Operational experience with the ATLAS Pixel detector at the LHC

    Deluca, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5\\% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, ...

  16. Operational Experience with the ATLAS Pixel Detector at the LHC

    Lange, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump- bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, a...

  17. Operational experience with the ATLAS Pixel detector at the LHC

    Deluca, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  18. SUPERCONDUCTING RADIO-FREQUENCY MODULES TEST FACILITY OPERATING EXPERIENCE

    Soyars, W.; Bossert, R.; Darve, C.; Degraff, B.; Klebaner, A.; Martinez, A.; Pei, L.; Theilacker, J.

    2008-01-01

    Fermilab is heavily engaged and making strong technical contributions to the superconducting radio-frequency research and development program (SRF R and D). Four major SRF test areas are being constructed to enable vertical and horizontal cavity testing, as well as cryomodule testing. The existing Fermilab cryogenic infrastructure has been modified to service the SRF R and D needs. The project's first stage has been successfully completed, which allows for distribution of cryogens for a single-cavity cryomodule using the existing Cryogenic Test Facility (CTF) that houses three Tevatron satellite refrigerators. The cooling capacity available for cryomodule testing at Meson Detector Building (MDB) results from the liquefaction capacity of the CTF cryogenic system. The cryogenic system for a single 9-cell cryomodule is currently operational. The paper describes the status, challenges and operational experience of the initial phase of the project

  19. Operating experience with the new TRIUMF RF control system

    Fong, K.; Laverty, M.; Fang, S.

    1995-06-01

    The 23 MHz rf control of the TRIUMF cyclotron has been replaced by a new VXI control system based on digital signal processing. It provides amplitude and phase regulation of the cyclotron dee voltage, as well as other functions such as power-up sequencing, spark and high VSWR protection. Modularity of the hardware is achieved by the VXI architecture, and in the software by Object Oriented Programming. It is expected that this will result in a considerably longer MTBF, and shorter fault diagnosis and repair times, than the equipment it replaces. The new system has now been in operation for over two months. The results of commissioning, testing, and early operating experience are presented. (author). 4 refs., 5 figs

  20. Operational experience with Seibersdorf low-level incinerator

    Chalupa, G.

    1987-01-01

    This report contains information about an excess air incinerator which burned low level β and γ wastes (also α up to determined limits). The incinerator was started up in 1980 and it is clear that in a technical plant of such magnitude, some changes and alterations will be needed to be overcome according to the experiences of operation. This paper - after a short description of the incinerator plant itself - gives a summary of some of the operation and the changes which are made in the plant according to these facts. A partial redesign of the incinerator plant in the first half of 1985 resulted in a very satisfying new design, which proved its superiority during the runs in 1985 and 1986

  1. Operational experience, availability and reliability of nuclear power plants

    Kueffer, K.

    1980-01-01

    This lecture - presents a survey on nuclear power production and plant performance in the Western World covering all reactor types and light-water reactors in particular and discusses key parameters such as load factors and non-availability analysis. - outlines the main reasons for the reliable performance of Swiss nuclear power plants - quality equipment - operator qualification and training - engineering know how on site - maintenance philosophy and outage planning - information system and feedback of experience - explains the management functions as applied at the Beznau Nuclear Power Station to ensure high power productivity and reliability - improvement - a feedback control system - analysis of production losses - optimization in shut-down planning - minimizing disturbances during plant operation - optimizing personnel qualification and efficiency. (orig.)

  2. Survey of operating experience from LERs to identify aging trends

    Murphy, G.A.

    1985-01-01

    The results of a study using the Oak Ridge National Laboratory's Nuclear Operations Analysis Center computer files of operating experience reports [licensee event reports (LERs), abnormal occurrences, etc.] are summarized in this study, specific time-related degradation mechanisms are identified as possible causes of a reportable occurrence. Data collected on domestic commercial nuclear power plants covering 1969 to 1982 yielded over 5800 events attributable to possible age related failures. Of these events, 2795 were attributable to instrument drift and are addressed separately in the report. The remaining events (3098) were reviewed, and data were collected for each event, which identified the specific system, component, and subpart: the information included the age-related mechanism, severity of the failure, and method of detection of the failure. About two-thirds of the failures were judged to be degraded, with one-third listed as catastrophic

  3. Operational Experience with a Cryogenic Axial-Centrifugal Compressor

    Decker, L; Löhlein, K; Purtschert, W; Ziegler, B L; Lebrun, P; Tavian, L; Brunovsky, I; Tucek, L

    1998-01-01

    The Large Hadron Collider (LHC), presently under construction at CERN, requires large refrigeration capacity at 1.8 K. Compression of gaseous helium at cryogenic temperatures is therefore inevitable. Together with subcontractors, Linde Kryotechnik has developed a prototype machine. This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating at ambient temperature. Integrated in a test facility for superconducting magnets the machine has been commissioned without major problems and successfully gone through the acceptance test in autumn 1995. Subsequent steps were initiated to improve efficiency of this prototype. This paper describes operating experience gained so far and reports on measured performance prior to and after constructional modifications.

  4. Safety aspects and operating experience of LWR plants in Japan

    Aoki, S.; Hinoki, M.

    1977-01-01

    From the outset of nuclear power development in Japan, major emphasis has been placed on the safety of the nuclear power plants. There are now twelve nuclear power plants in operation with a total output of 6600 MWe. Their operating records were generally satisfactory, but in the 1974 to 1975 period, they experienced somewhat declined availability due to the repair work under the specific circumstances. After investigation of causes of troubles and the countermeasures thereof were made to ensure safety, they are now keeping good performance. In Japan, nuclear power plants are strictly subject to sufficient and careful inspection in compliance with the safety regulation, and are placed under stringent radiation control of employees. Under the various circumstances, however, the period of annual inspection tends to be prolonged more than originally planned, and this consequently is considered to be one of the causes of reduced availability. In order to develop nuclear power generation for the future, it is necessary to put further emphasis on the assurance of safety and to endeavor to devise measures to improve availability of the plants, based on the careful analysis of causes which reduce plant availability. This paper discusses the results of studies made for the following items from such viewpoints: (1) Safety and Operating Experience of LWR Nuclear Power Plants in Japan; a) Operating experience with light water reactors b) Improvements in design of light water reactors during the past ten years c) Analysis of the factors which affect plant availability; 2) Assurance of Safety and Measures to Increase Availability a) Measures for safety and environmental protection b) Measures to reduce radiation exposure of employees c) Appropriateness of maintenance and inspection work d) Measures to increase plant availability e) Measures to improve reliability of equipments and components; and 3) Future Technical Problems

  5. Vascular Trauma Operative Experience is Inadequate in General Surgery Programs.

    Yan, Huan; Maximus, Steven; Koopmann, Matthew; Keeley, Jessica; Smith, Brian; Virgilio, Christian de; Kim, Dennis Y

    2016-05-01

    Vascular injuries may be challenging, particularly for surgeons who have not received formal vascular surgery fellowship training. Lack of experience and improper technique can result in significant complications. The objective of this study was to examine changes in resident experience with operative vascular trauma over time. A retrospective review was performed using Accreditation Council for Graduate Medical Education (ACGME) case logs of general surgery residents graduating between 2004 and 2014 at 2 academic, university-affiliated institutions associated with level 1 trauma centers. The primary outcome was number of reported vascular trauma operations, stratified by year of graduation and institution. A total of 112 residents graduated in the study period with a median 7 (interquartile range 4.5-13.5) vascular trauma cases per resident. Fasciotomy and exposure and/or repair of peripheral vessels constituted the bulk of the operative volume. Linear regression showed no significant trend in cases with respect to year of graduation (P = 0.266). Residents from program A (n = 53) reported a significantly higher number of vascular trauma cases when compared with program B (n = 59): 12.0 vs. 5.0 cases, respectively (P < 0.001). Level 1 trauma center verification does not guarantee sufficient exposure to vascular trauma. The operative exposure in program B is reflective of the national average of 4.0 cases per resident as reported by the ACGME, and this trend is unlikely to change in the near future. Fellowship training may be critical for surgeons who plan to work in a trauma setting, particularly in areas lacking vascular surgeons. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. BR3/Vulcain Nuclear Power Station. Construction and Operational Experience

    Storrer, J. [Belgonucleaire, S.A., Brussels (Belgium)

    1968-04-15

    A full-scale reactor experiment was set out as the main objective of the Vulcain research and development programme agreed in May 1962 between the UKAEA and BelgoNucleaire, manager of ''Syndicat Vulcain''. Vulcain uses variable moderation as the long-term method to control reactivity: the reactor is cooled and moderated by a mixture of heavy and light water, the D{sub 2}O content being stepwise reduced to permit power operation with all control rods completely out of the core. To carry out the Vulcain power experiment it was decided to modify the BR3 nuclear power plant located at Mol, Belgium, which had operated from 1962 to 1964 as a conventional PWR with outputs of 40.9 MW(th) and 11.45 MW(e). The BR3/Vulcain plant was started in December 1966 and since then is running with a load factor around 90%. It is the first time that such a reactor type has been built and operated and the experience gained by its design, construction, commissioning and operation has proven to be most valuable. D{sub 2}O is being used at a pressure (2000 lb/in{sup 2} abs.) never before achieved in a heavy-water reactor and the leak rate from the HP primary systems to the atmosphere has been kept to a negligible value, around 1 to 2 grams/h. Commissioning of the primary plant had been carried out with light water first without fuel, and thereafter with fuel, at which time the water was poisoned with boric acid. The reactor vessel contains experimental devices such as 65 in-pile instrumentation detectors and four hydraulically operated Zircaloy control rods. They required the interposition of a collar between the vessel and its lid. Refuelling is performed under boronated light water, the interchange between the primary water and the H{sub 2}O being carried out by means of a draining and spraying system. The reactor had been operated for two years before its modifications for Vulcain: many lessons have therefore been learned about working on irradiated systems. The BR3/Vulcain core has a

  7. The continuation training of operators and feedback of operational experience in the Royal Navy's nuclear submarine programme

    Manson, R.P.

    1983-01-01

    Naval continuation training has relied heavily on the use of realistic simulators for over ten years, and this has been proved to be a cost-effective and efficient method of training. The type of simulator used, the selection and qualification of simulator instructors, and the method of training experienced operators is described. Also, the assessment of operator performance, the use of simulators during the final stages of operator qualification, and their use for training operators on plant operation whilst shut-down are covered. The Navy also pays great attention to the feedback of operating experience from sea into both continuation and basic training. This is accomplished using Incident Reports, which are rendered whenever the plant is operated outside the approved Operating Documentation, or when any other unusual circumstance arises. Each Report is individually assessed and replied to by a qualified operator, and those incidents of more general interest are published in a wider circulation document available to all plant operators. In addition, each crew is given an annual lecture on recent operating experiences. Important lessons are fed forward into new plant design, and the incident reports are also used as a source of information for plant reliability data. (author)

  8. Plant operator performance evaluation based on cognitive process analysis experiment

    Ujita, H.; Fukuda, M.

    1990-01-01

    This paper reports on an experiment to clarify plant operators' cognitive processes that has been performed, to improve the man-machine interface which supports their diagnoses and decisions. The cognitive processes under abnormal conditions were evaluated by protocol analyses interviews, etc. in the experiment using a plant training simulator. A cognitive process model is represented by a stochastic network, based on Rasmussen's decision making model. Each node of the network corresponds to an element of the cognitive process, such as observation, interpretation, execution, etc. Some observations were obtained as follows, by comparison of Monte Carlo simulation results with the experiment results: A process to reconfirm the plant parameters after execution of a task and feedback paths from this process to the observation and the task definition of next task were observed. The feedback probability average and standard deviation should be determined for each incident type to explain correctly the individual differences in the cognitive processes. The tendency for the operator's cognitive level to change from skill-based to knowledge-based via rule-based behavior was observed during the feedback process

  9. Exploitation of the in-seam miner and operational experience

    Wilson, W I.S.; Morris, A H

    1977-12-01

    The In-seam Miner started as an investigatory project at MRDE in 1969. Since that time it has passed through the classic development stages of design of prototype, surface trials, underground trials, modification, production of more machines, assessment of experience and then wider exploitation. At the present time well over 100 machines have been supplied to the National Coal Board. The original machine was hydraulically driven and all but five of the machines supplied to date are of this type. The variety of applications that the machine has found in the mining industry has caused derivative development to embrace machines of length varying from 12-ft centers to 44-ft centers, to work in seams ranging from 40 in. up to 68 in. The range of applications has included face drivages, stablehole operations, in-seam retreat roadways and dirt-absorbing headings. Five electrically driven machines are now coming onto the market and experience with them, though limited, is very encouraging. The paper concentrates on two major aspects of the overall development process: first, the management of exploitation; and second, some operational experience of the In-seam Miner in South Midlands area.

  10. Operating experience and design criteria of sodium valves

    Markford, D.

    1974-01-01

    The information presented refers to sodium valve development for KNK and SNR-300 as well as for sodium test facilities on the INTERATOM site at Bensberg. Well in advance of KNK-I a number of sodium test facilities have been operated containing small and medium size valves of different design and manufacturer. The more stringent requirements for long range safe and reliable operation in KNK-I put forth a development program for the main primary and secondary circuit sodium valves. Operational experience gave rise to modification of the stem seal arrangement mainly, so KNK-II (which is the fast core for KNK reactor) will be run with modified sodium valves. Main pipe diameters in SNR-300 are in the range of 600 mm. Valve designs with rising shafts would require excessive space in the primary circuit cavities, therefore efforts have been directed towards introduction of different type valves. Due to the requirements of after-heat-removal a valve type with control capability had to be chosen. A special design of butterfly valves was selected for the primary and secondary circuits of SNR-300. The development and tests performed with this type of valve are described. In the field of small sodium valves, tests with a 50 mm diameter freeze-seal valve are reported, and the current status of bellows-seal-valves to be inserted into SNR-300 is discussed. (U.S.)

  11. Highly active vitrification plant remote handling operational experience and improvements

    Milgate, I.

    1996-01-01

    All the main process plant and equipment at the Sellafield Waste Vitrification Plant (WVP) is enclosed in heavily shielded concrete walled cells. There is a large quantity of relatively complex plant and equipment which must be remotely operated, maintained or replaced in-cell in a severe environment. The WVP has five in-cell polar cranes which are of modular construction to aid replacement of failed components. Each can be withdrawn into a shielded cell extension for decontamination and hands-on maintenance. The cells have a total of 80 through wall tube positions to receive Master Slave Manipulators (MSMs). The MSMs are used where possible for ''pick and place'' purposes but are often called upon to position substantial pieces of mechanical equipment and thus are subject to heavy loading and high failure rates. An inward flow of air is maintained in the active cells. The discharged air passes through a filter cell where remote damper operation filter changing and maintenance is carried out by means of a PAR3000 manipulator. A Nuclear Engineered Advanced Teleoperated Robot (Neater) swabs the vitrified product container to ensure cleanliness before storage. There is a significant arising of solid radioactive waste from replaced in-cell items which undergoes sorting and size reduction in a breakdown cell equipped with a large reciprocating saw and a hydraulic shear. Improvements to the remote handling facilities made in the light of operational experience are described. (UK)

  12. Operational experience - Lessons learned from IRS-reports in Germany

    Wetzel, N.; Maqua, M.

    2005-01-01

    The international Incident Reporting System (IRS), jointly operated by IAEA and OECD-NEA, is a main source of safety significant findings and lessons learned of nuclear operating experience. GRS (Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH) is a scientific-technical expert and research organisation. On Behalf of the Federal Minister of Environment, Nature Conservation and Reactor Safety (BMU), GRS provides the IRS officer. The evaluation of IRS-Reports and the dissemination of the main findings including the assessment of the relevance for German NPPs is task of GRS. The value of IRS is among experts undoubted. But nevertheless, the reporting to IRS decreases since some years. This presentation is aimed to show the support of IRS in strengthening the safety of German NPPs. The evaluation of IRS-Reports at GRS is three-fold. It comprises initial screening, quarterly and yearly reporting and the development of specific German Information Notices on safety significant events with direct applicability to German NPPs. Some examples of lessons learned from recent international events are discussed below. These examples shall demonstrate that the use of the IRS enhances significantly the knowledge on operational events. (author)

  13. LANL operating experience with the WAND and HERCULES prototype systems

    Gruetzmacher, K. M.; Foxx, C. L.; MYERS, S. C.

    2000-01-01

    The Waste Assay for Nonradioactive Disposal (WAND) and the High Efficiency Radiation Counters for Ultimate Low Emission Sensitivity (HERCULES) prototype systems have been operating at Los Alamos National Laboratory's (LANL's) Solid Waste Operation's (SWO'S) non-destructive assay (NDA) building since 1997 and 1998, respectively. These systems are the cornerstone of the verification program for low-density Green is Clean (GIC) waste at the Laboratory. GIC waste includes all non-regulated waste generated in radiological controlled areas (RCAS) that has been actively segregated as clean (i.e., nonradioactive) through the use of waste generator acceptable knowledge (AK). The use of this methodology alters LANL's past practice of disposing of all room trash generated in nuclear facilities in radioactive waste landfills. Waste that is verified clean can be disposed of at the Los Alamos County Landfill. It is estimated that 50-90% of the low-density room trash from radioactive material handling areas at Los Alamos might be free of contamination. This approach avoids the high cost of disposal of clean waste at a radioactive waste landfill. It also reduces consumption of precious space in the radioactive waste landfill where disposal of this waste provides no benefit to the public or the environment. Preserving low level waste (LLW) disposal capacity for truly radioactive waste is critical in this era when expanding existing radioactive waste landfills or permitting new ones is resisted by regulators and stakeholders. This paper describes the operating experience with the WAND and HERCULES since they began operation at SWO. Waste for verification by the WAND system has been limited so far to waste from the Plutonium Facility and the Solid Waste Operations Facility. A total of461 ft3 (13.1 m3) of low-density shredded waste and paper have been verified clean by the WAND system. The HERCULES system has been used to verify waste from four Laboratory facilities. These are the

  14. Lessons Learned from Missing Flooding Barriers Operating Experience

    Simic, Z.; Veira, M. P.

    2016-01-01

    Flooding hazard is highly significant for nuclear power plant safety because of its potential for common cause impact on safety related systems, and because operating experience reviews regularly identify flooding as a cause of concern. Source of the flooding could be external (location) or internal (plant design). The amount of flooding water could vary but even small amount might suffice to affect redundant trains of safety related systems for power supply and cooling. The protection from the flooding is related to the design-basis flood level (DBFL) and it consists of three elements: structural, organizational and accessibility. Determination of the DBFL is critical, as Fukushima Daiichi accident terribly proved. However, as the topic of flooding is very broad, the scope of this paper is focused only on the issues related to the missing flood barriers. Structural measures are physically preventing flooding water to reach or damage safety related system, and they could be permanent or temporary. For temporary measures it is important to have necessary material, equipment and organizational capacity for the timely implementation. Maintenance is important for permanent protection and periodical review is important for assuring readiness and feasibility of temporary flooding protection. Final flooding protection element is assured accessibility to safety related systems during the flooding. Appropriate flooding protection is based on the right implementation of design requirements, proper maintenance and periodic reviews. Operating experience is constantly proving how numerous water sources and systems interactions make flooding protection challenging. This paper is presenting recent related operating experience feedback involving equipment, procedures and analysis. Most frequent deficiencies are: inadequate, degraded or missing seals that would allow floodwaters into safety related spaces. Procedures are inadequate typically because they underestimate necessary

  15. Operational experience with two tritium-effluent-monitoring systems

    Haynie, J.S.; Gutierrez, J.A.

    1982-01-01

    Two new tritium stack monitoring systems were designed and built. The operational experience of a wide-range detector with a useful range of a few μCi/m 3 to 10 8 μCi/m 3 , and a second monitoring system using an improved Kanne chamber and a new electrometer, called a Model 39 Electrometer-Chargemeter are discussed. Both tritium chambers have been designed to have a reduced sensitivity to tritium contamination, a fast response, and an integrating chargemeter with digital readout for easy conversion to microcuries. The calibration of these monitors and advantages of using these chambers over conventional systems are discussed

  16. Operating experiences in fuel handling system at KGS

    Reddy, G.P.; Nagabhushanam

    2006-01-01

    Refuelling operations were started at KGS in August, 2000. Rich and varied experience was gained during this period through internal discussion/Quality circles/Procedural reviews and analysis of various incidents that have taken place in KGS and other units of NPCIL Some of the unique jobs carried out at KGS include-Development of tools for in-situ replacement of FM front end cover in FM service area (which was done for the first time in NPCIL history), Modification of FM magazine rear end plate mounting screws to avoid the possibility of magazine rotation stalling, The incident of Stalling of B-Ram during installation of upstream shield plug in KGS - 1 has brought out many weakness that were existing in the system in a dormant manner. Review of maintenance procedures was carried out and a special underwater operated sensor was developed and installed in Transfer Magazine to sense the presence and proper positioning of fuel bundles in the Transfer magazine tube during fuel loading operation. Numerous modifications were carried out in the system to increase equipment reliability, ease of operation and maintenance, to reduce man-rem consumption. Most notable among these modifications include -zig saw panel modification, EFCV O-ring modification, Ram BF switch modification, provision for increase in SFSB level provision, snout clamp oil circuit modification, ball valve actuator modification, installation of additional switch for sensing STS carriage UP position etc, This paper focuses on the challenges tackled in achieving near perfect performance, innovations and improvements carried out in the system to strive for this goal and development of procedures for reducing man-rem consumption and life extension of critical components. (author)

  17. Nuclear power operating experience and technical improvement in Japan

    Toyota, M.

    1983-01-01

    LWR technology in Japan, originally introduced from the United States of America, is now almost entirely supplied domestically. During the initial stage of plant operation, electric power companies experienced various troubles such as intergranular stress corrosion cracking (IGSCC) in the piping in BWRs and steam generator (S/G) tube leaks in PWRs, which once reduced the capacity factor to about 40%. As a result of efforts to investigate the causes of the troubles and to establish countermeasures, which were applied to the plants in operation and under construction for improvement, as well as to shorten the period of regular inspection and to extend the operation cycle, the capacity factor has been improved to 60% since 1980. In 1975 an LWR improvement and standardization programme was launched to aim at improvement of reliability and availability factor and reduction of occupational radiation exposure with the development of domestic technology based on construction and operating experience. The First Phase Programme, which ran from 1975 to 1977, established countermeasures to preclude these troubles and improved workability by enlargement of the containment vessel. The Second Phase Programme followed and ran until 1981. The major steps taken during this period include the adoption of new IGSCC-resistant material and improved core design for BWRs and the improvement of fuels and S/Gs for PWRs. With these improvements, the capacity factor is now expected to reach a 75% level and occupational radiation exposure should be reduced by 50%. A Third Phase Programme will centre on the test and development programme for advanced BWRs and PWRs now under way to further improve the availability factor and reliability while also minimizing radiation exposure. (author)

  18. Integrating Renewable Generation into Grid Operations: Four International Experiences

    Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mylrea, Michael E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Levin, Todd [Argonne National Lab. (ANL), Argonne, IL (United States); Botterud, Audun [Argonne National Lab. (ANL), Argonne, IL (United States); O' Shaughnessy, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-04-22

    International experiences with power sector restructuring and the resultant impacts on bulk power grid operations and planning may provide insight into policy questions for the evolving United States power grid as resource mixes are changing in response to fuel prices, an aging generation fleet and to meet climate goals. Australia, Germany, Japan and the UK were selected to represent a range in the level and attributes of electricity industry liberalization in order to draw comparisons across a variety of regions in the United States such as California, ERCOT, the Southwest Power Pool and the Southeast Reliability Region. The study draws conclusions through a literature review of the four case study countries with regards to the changing resource mix and the electricity industry sector structure and their impact on grid operations and planning. This paper derives lessons learned and synthesizes implications for the United States based on answers to the above questions and the challenges faced by the four selected countries. Each country was examined to determine the challenges to their bulk power sector based on their changing resource mix, market structure, policies driving the changing resource mix, and policies driving restructuring. Each countries’ approach to solving those changes was examined, as well as how each country’s market structure either exacerbated or mitigated the approaches to solving the challenges to their bulk power grid operations and planning. All countries’ policies encourage renewable energy generation. One significant finding included the low- to zero-marginal cost of intermittent renewables and its potential negative impact on long-term resource adequacy. No dominant solution has emerged although a capacity market was introduced in the UK and is being contemplated in Japan. Germany has proposed the Energy Market 2.0 to encourage flexible generation investment. The grid operator in Australia proposed several approaches to maintaining

  19. Lessons learned from operating experience, maintenance procedures and training measures

    Guttner, K.; Gronau, D.

    2003-01-01

    Training programmes for nuclear facility personnel as a result of the developing phase of SAT have to be approved in the subsequent implementation and evaluation phases with the consequence of several feedback activities in the whole training process. The effectiveness of this procedure has to be evaluated especially with respect to an improvement of safety culture, shorter outage times or better plant performance, resulting in a smaller number of incidents due to human failures. The first two arguments are directly connected with all types of maintenance work in a nuclear power plant and the related preparatory training measures. The reduction of incidents due to human failures is the result of different influences, i.e. training of the operational as well as of the maintenance personnel together with changes of the operating procedures or system design. Though an evaluation of the training process should always be based on a clear definition of criteria by which the fulfilment of the learning objectives can be measured directly, the real effectiveness of training is proven by the behaviour and attitude of the personnel which can only be taken from indirect indicators. This is discussed in more detail for some examples being partly related to the above mentioned arguments. An excellent plant performance, representing a general objective of all activities, can be analysed by the changed number and reasons of incidents in a plant during its operation time. Two further examples are taken from the reactor service field where there is a tendency to reduce the individual dose rates by changed devices and/or procedures as an output from training experience with mockups. Finally the rationalisation of refresher training for operational personnel by the use of interactive teaching programs (Computer Based Training - CBT) is presented which integrate learning objectives together with a test module. (author)

  20. Sonography of the painful shoulder: role of the operator's experience

    Corroller, Thomas Le; Cohen, Michel; Champsaur, Pierre; Aswad, Richard; Pauly, Vanessa

    2008-01-01

    The aim of our study was to determine the role of the operator's experience in the sonographic evaluation of the painful shoulder and to validate assumptions about its technical performance in routine practice. Two radiologists, respectively standard and expert sonographic operators, independently and prospectively scanned 65 patients with clinical suspicion of rotator cuff lesion. Magnetic resonance arthrography was the reference standard. The sensitivity of the expert ultrasound operator was 95.3% for full-thickness rotator cuff tears (41/43), 70.6% for partial-thickness tears (12/17), 64.3% for intratendinous tears (9/14), 100% for abnormality of the long head of biceps tendon (seven of seven), 88.9% for supraspinatus tendinosis (16/18), 96.4% for subacromial bursa abnormalities (53/55), and 91.7%for acromioclavicular joint osteoarthritis (33/36). The two sonographic operators were in very good agreement about full-thickness rotator cuff tears (κ=0.90), supraspinatus tendinosis (κ =0.80), abnormalities of the long head of biceps tendon (κ=0.84), subacromial bursa abnormalities (κ=0.89), and acromioclavicular osteoarthritis (κ=0.81). The agreement was only moderate for partial-thickness tears (κ=0.63) and intratendinous tears (κ=0.57). Our results show that in moderately experienced hands as in experts' hands, sonography has a low level of interobserver variability for full-thickness rotator cuff tears. Considering partial-thickness and intratendinous rotator cuff tears, our data suggest that interobserver variability is higher. (orig.)

  1. BWR and PWR chemistry operating experience and perspectives

    Fruzzetti, K.; Garcia, S.; Lynch, N.; Reid, R.

    2014-01-01

    It is well recognized that proper control of water chemistry plays a critical role in ensuring the safe and reliable operation of Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). State-of-the-art water chemistry programs reduce general and localized corrosion of reactor coolant system, steam cycle equipment, and fuel cladding materials; ensure continued integrity of cycle components; and reduce radiation fields. Once a particular nuclear plant component has been installed or plant system constructed, proper water chemistry provides a global tool to mitigate materials degradation problems, thereby reducing the need for costly repairs or replacements. Recognizing the importance of proper chemistry control and the value in understanding the relationship between chemistry guidance and actual operating experience, EPRI continues to collect, monitor, and evaluate operating data from BWRs and PWRs around the world. More than 900 cycles of valuable BWR and PWR operating chemistry data has been collected, including online, startup and shutdown chemistry data over more than 10 years (> 20 years for BWRs). This paper will provide an overview of current trends in BWR and PWR chemistry, focusing on plants in the U.S.. Important chemistry parameters will be highlighted and discussed in the context of the EPRI Water Chemistry Guidelines requirements (i.e., those parameters considered to be of key importance as related to the major goals identified in the EPRI Guidelines: materials integrity; fuel integrity; and minimizing plant radiation fields). Perspectives will be provided in light of recent industry initiatives and changes in the EPRI BWR and PWR Water Chemistry Guidelines. (author)

  2. Installation and first operation of the negative ion optimization experiment

    De Muri, Michela; Cavenago, Marco; Serianni, Gianluigi; Veltri, Pierluigi; Bigi, Marco; Pasqualotto, Roberto; Barbisan, Marco; Recchia, Mauro; Zaniol, Barbara; Kulevoy, Timour; Petrenko, Sergey; Baseggio, Lucio; Cervaro, Vannino; Agostini, Fabio Degli; Franchin, Luca; Laterza, Bruno; Minarello, Alessandro; Rossetto, Federico; Sattin, Manuele; Zucchetti, Simone

    2015-01-01

    Highlights: • Negative ion sources are key components of the neutral beam injectors. • The NIO1 experiment is a RF ion source, 60 kV–135 mA hydrogen negative ion beam. • NIO1 can contribute to beam extraction and optics thanks to quick replacement and upgrading of parts. • This work presents installation, status and first experiments results of NIO1. - Abstract: Negative ion sources are key components of the neutral beam injectors for thermonuclear fusion experiments. The NIO1 experiment is a radio frequency ion source generating a 60 kV–135 mA hydrogen negative ion beam. The beam is composed of nine beamlets over an area of about 40 × 40 mm"2. This experiment is jointly developed by Consorzio RFX and INFN-LNL, with the purpose of providing and optimizing a test ion source, capable of working in continuous mode and in conditions similar to those foreseen for the larger ion sources of the ITER neutral beam injectors. At present research and development activities on these ion sources still address several important issues related to beam extraction and optics optimization, to which the NIO1 test facility can contribute thanks to its modular design, which allows for quick replacement and upgrading of components. This contribution presents the installation phases, the status of the test facility and the results of the first experiments, which have demonstrated that the source can operate in continuous mode.

  3. Operating Experience of MACSTOR Modules at CANDU 6 Stations

    Beaudoin, Robert R.

    2005-01-01

    Over the last three decades, Atomic Energy of Canada Limited (AECL) has contributed to the technology development and implementation of dry spent fuel management facilities in Canada, Korea and Romania During that period, AECL has developed a number of concrete canister models and the MACSTOR200 module, a medium size air-cooled vault with a 228 MgU (Mega grams of Uranium) capacity. AECL's dry storage technologies were used for the construction of eight large-scale above ground dry storage facilities for CANDU spent fuel. As of 2005, those facilities have an installed capacity in excess of 5,000 MgU. Since 1995, the two newest dry storage installations built for CANDU 6 reactors at Gentilly 2 (Canada) and Cernavoda (Romania) used the MACSTOR 200 module. Seven such modules have been built at Gentilly 2 during the 1995 to 2004 period and one at Cernavoda in 2003. The construction and operating experience of those modules is reviewed in this paper. The MACSTOR 200 modules were initially designed for a 50-year service life, with recent units at Gentilly 2 licensed for a 100-year service life in a rural (non-maritime) climate. During the 1995-2005 period, six of the eight modules were loaded with fuel. Their operation has brought a significant amount of experience on loading operations, performance of fuel handling equipment, radiation shielding, heat transfer, monitoring of the two confinement boundaries and radiation dose to personnel. Heat dissipation performance of the MACSTOR 200 was initially licensed using values derived from full scale tests made at AECL's Whiteshell Research Laboratories, that were backed-up by temperature measurements made on the first two modules. Results and computer models developed for the MACSTOR 200 module are described. Korea Hydro and Nuclear Power (KHNP) and its subsidiary Nuclear Environment Technology Institute (NETEC), in collaboration with Hyundai Engineering Company Ltd. (HEC) and AECL, are developing a new dry storage module to

  4. OECD/NEA component operational experience, degradation and ageing project

    Gott, K.; Nevander, O.; Riznic, J.; Lydell, B.

    2015-01-01

    Several OECD Member Countries have agreed to establish the OECD/NEA 'Component Operational Experience, Degradation and Ageing Programme' (CODAP) to encourage multilateral co-operation in the collection and analysis of data relating to degradation and failure of metallic piping and non-piping metallic passive components in commercial nuclear power plants. The scope of the data collection includes service-induced wall thinning, part through-wall cracks, through-wall cracks with and without active leakage, and instances of significant degradation of metallic passive components, including piping pressure boundary integrity. CODAP is the continuation of the 2002-2011 'OECD/NEA Pipe Failure Data Exchange Project' (OPDE) and the Stress Corrosion Cracking Working Group of the 2006-2010 - OECD/NEA SCC and Cable Ageing project - (SCAP). OPDE was formally launched in May 2002. Upon completion of the 3. Term (May 2011), the OPDE project was officially closed to be succeeded by CODAP. In May 2011, 13 countries signed the CODAP first Term agreement. The first Term (2011-2014) work plan includes the development of a web-based relational event database on passive, metallic components in commercial nuclear power plants, a web-based knowledge base on material degradation, codes and standards relating to structural integrity and national practices for managing material degradation. The work plan also addresses the preparation of Topical Reports to foster technical cooperation and to deepen the understanding of national differences in ageing management. These Topical Reports are in the public domain and available for download on the NEA web site. Published in 2014, a first Topical Report addressed flow accelerated corrosion (FAC) of carbon steel and low alloy steel piping. A second Topical Report addresses operating experience with electro-hydraulic control (EHC) and instrument air (IA) system piping

  5. Reactor operation

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  6. Remotely Operated Vehicles under sea ice - Experiences and results from five years of polar operations

    Katlein, Christian; Arndt, Stefanie; Lange, Benjamin; Belter, Hans Jakob; Schiller, Martin; Nicolaus, Marcel

    2016-04-01

    The availability of advanced robotic technologies to the Earth Science community has largely increased in the last decade. Remotely operated vehicles (ROV) enable spatially extensive scientific investigations underneath the sea ice of the polar oceans, covering a larger range and longer diving times than divers with significantly lower risks. Here we present our experiences and scientific results acquired from ROV operations during the last five years in the Arctic and Antarctic sea ice region. Working under the sea ice means to have all obstacles and investigated objects above the vehicle, and thus changes several paradigms of ROV operations as compared to blue water applications. Observations of downwelling spectral irradiance and radiance allow a characterization of the optical properties of sea ice and the spatial variability of the energy partitioning across the atmosphere-ice-ocean boundary. Our results show that the decreasing thickness and age of the sea ice have led to a significant increase in light transmission during summer over the last three decades. Spatially extensive measurements from ROV surveys generally provide more information on the light field variability than single spot measurements. The large number of sampled ice conditions during five cruises with the German research icebreaker RV Polarstern allows for the investigations of the seasonal evolution of light transmittance. Both, measurements of hyperspectral light transmittance through sea ice, as well as classification of upward-looking camera images were used to investigate the spatial distribution of ice-algal biomass. Buoyant ice-algal aggregates were found to be positioned in the stretches of level ice, rather than pressure ridges due to a physical interaction of aggregate-buoyancy and under-ice currents. Synchronous measurements of sea ice thickness by upward looking sonar provides crucial additional information to put light-transmittance and biological observations into context

  7. Fabrication and operational experience with the interim storage cask

    Scott, P.L.

    1998-01-01

    This paper discusses the fabrication and operational experience of the Interim Storage Cask (ISC). The ISC is a dry storage cask which is used to safely store a Core Component Container (CCC) containing up to seven Fast Flux Test Facility (FFTF) spent fuel assemblies at the US Department of Energy's Hanford Site. Under contract to B and W Hanford Company (BWHC), General Atomics (GA) designed and fabricated thirty ISC casks which BWHC is remotely loading at the FFTF facility. BWHC designed and fabricated the CCCS. As of December 1997, thirty ISCs have been fabricated, of which eighteen have been loaded and moved to a storage site adjacent to the FFTF facility. Fabrication consisted of three sets of casks. The first unit was completed and acceptance tested before any other units were fabricated. After the first unit passed all acceptance tests, nine more units were fabricated in the first production run. Before those nine units were completed, GA began a production run of twenty more units. The paper provides an overview of the cask design and discusses the problems encountered in fabrication, their resolution, and changes made in the fabrication processes to improve the quality of the casks. The paper also discusses the loading process and operational experiences with loading and handling of the casks. Information on loading times, worker dose exposure, and total dose for loading are presented

  8. An overview of KANUPP operating experience in chemistry

    Hashmi, T.

    2010-01-01

    KANUPP is a small CANDU® type PHWR (137MWe), commissioned in 1972 and now operating after life extension (PLEX) since 2004. This paper contains an overview of the plant operating experience in chemistry control over the past year including life extension period. Emphasis is on: Success story; Practices; Future improvements in chemistry programs. Considerable efforts are underway to maintain plant equipment and systems to mitigate the effect of plant ageing. The improvements that have been made at the station are as under: Heat transport system (HTS) chemistry, its effects on construction material; Feed water chemistry on secondary side (considering the condenser leaks). Strict chemistry control is being exercised for the heat transport system (HTS) for its better chemistry control. For short term, the changes are limited to pH adjustments of HTS. This change decreases the rate of thinning of outlet feeders as noted in some CANDUs® due to flow accelerated corrosion (FAC). Water Treatment Plant has been refurbished to get very low total dissolved solids (TDS) de-mineralized water for secondary side systems of the plant. Experience of steam generators flushing before startup, sludge pile analyses mapping, verification of pH from different sampling points of SGs, are the short term mitigating actions to address sludge pile problem in steam generators (SGs). The R and D on HTS and SGs is multifaceted and is aimed at achieving optimum chemistry control. Study is being conducted for improving chemistry control for the material, equipment and systems of the plant. (author)

  9. Halden fuel and material experiments beyond operational and safety limits

    Volkov, Boris; Wiesenack, Wolfgang; McGrath, M.; Tverberg, T.

    2014-01-01

    One of the main tasks of any research reactor is to investigate the behavior of nuclear fuel and materials prior to their introduction into the market. For commercial NPPs, it is important both to test nuclear fuels at a fuel burn-up exceeding current limits and to investigate reactor materials for higher irradiation dose. For fuel vendors such tests enable verification of fuel reliability or for the safety limits to be found under different operational conditions and accident situations. For the latter, in-pile experiments have to be performed beyond some normal limits. The program of fuel tests performed in the Halden reactor is aimed mainly at determining: The thermal FGR threshold, which may limit fuel operational power with burn-up increase, the “lift-off effect” when rod internal pressure exceeds coolant pressure, the effects of high burn-up on fuel behavior under power ramps, fuel relocation under LOCA simulation at higher burn-up, the effect of dry-out on high burn-up fuel rod integrity. This paper reviews some of the experiments performed in the Halden reactor for understanding some of the limits for standard fuel utilization with the aim of contributing to the development of innovative fuels and cladding materials that could be used beyond these limits. (author)

  10. Experience with managing, operating and maintaining gas turbine powerplants

    Wadman, B.

    1994-01-01

    Stewart ampersand Stevenson, a major supplier of gas turbine powered cogeneration systems to worldwide markets, established plant management, operations and maintenance capabilities in 1985 in order to provide complete service capability to the customer. As of the fall of 1993, twenty-two individual cogeneration facilities are now being operated and maintained by this company with a total capacity of 1100+ MW. More than 300 plant management and operating personnel are employed in this operation. To date, activities have been concentrated in North and South America. Negotiations are in process in a number of other areas including the Pacific Rim, China, and several Middle East countries. 7 figs

  11. Experience from construction and operation of Karachi nuclear power plant

    Zaidi, S.M.N.

    1977-01-01

    Pakistan's first nuclear power plant (KANUPP) is owned and operated by the Pakistan Atomic Energy Commission (PAEC). It uses a heavy water moderated and cooled natural uranium fuelled reactor. Total installed capacity is 137 MW(e). It was designed, constructed and commissioned by Canadian General Electric Co. Ltd. (CGE) as Prime Contractor. Construction started in mid-1966 and was completed in mid 1970; commissioning started in early 1970 and was completed at the end of 1972. Intensive on-the-job training for 20 engineers and 15 operators was provided by CGE in Canada. Ten engineers also worked in CGE's design offices. With this key group of engineers and technicians PAEC had no difficulty in taking over the plant from CGE after completion. The construction of the plant in a developing country presented special problems to CGE. The relatively small local construction firms had limited experience and equipment. Construction plant, equipment and tools were scarce. Fabrication and workshop facilities of limited scope were available but their quotations were relatively high. A scarcity of engineering, technical and skilled manpower for the construction of the project left as the only alternative on-site training for carefully recruited technicians. The results were most gratifying and compared favourably with CGE's Canadian experience. Welding, pipe fitting, tubing work and electrical connections were excellent. The local staff's productivity and dedication were very good. In the commissioning period, PAEC and CGE engineers and technicians worked as one team, testing and debugging the equipment and systems and demonstrating the contractual performance warranties. This period extended to approximately three years due to many technical problems resulting from equipment failures, environmental problems, system problems, plant loading limitations in view of the relatively small size of the grid system and special requirement of fuel conditioning to avoid premature fuel

  12. An Experiment on the Impact of Communication Problems in the Multi-cultural Operation of NPPs' Emergency Operation

    Kang, Seongkeun; Lee, Chanyoung; Seong, Poong Hyun; Ha, Jun Su

    2015-01-01

    Korean government won a contract of nuclear power plants to UAE government in 2010 and nuclear power plants are now under construction in Barakah, UAE. However, with technology transfer and international cooperation, there needs to consider several potential problems due to the differences between two culture of the countries such as language, technical culture and expectation. It is unknown how potential problems can lead to an unsafe plant operation as well. We got to know language problem is the main issue from analyzing the OERs. Korean nuclear power plant operators will work in UAE and they will operate the NPPs with other countries' operators and managers. Therefore they will have to use English when they communicate each other. The purpose of this paper is to confirm how much operators get stress and how much accuracy is declined when operators communicate together in English. Reducing human error is quite important to make nuclear power plants safety. As mental workload of human operator is increased, operators get more stress, then the probability of occurring human error may be increased. It will affect bad influence to nuclear power plants safety. There are many factors to make mental workload increased. We focused on communication problem which is a key factor of the increasing mental workload because many Korean operators will work in UAE nuclear power plants and they may work together with UAE operators. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To find the impact of how much English affects the operators' workload, we did two cases of experiments; one is experiment for diagnosis and the other is experiment for execution

  13. An Experiment on the Impact of Communication Problems in the Multi-cultural Operation of NPPs' Emergency Operation

    Kang, Seongkeun; Lee, Chanyoung; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of); Ha, Jun Su [KUSTAR, Abu Dhabi (United Arab Emirates)

    2015-10-15

    Korean government won a contract of nuclear power plants to UAE government in 2010 and nuclear power plants are now under construction in Barakah, UAE. However, with technology transfer and international cooperation, there needs to consider several potential problems due to the differences between two culture of the countries such as language, technical culture and expectation. It is unknown how potential problems can lead to an unsafe plant operation as well. We got to know language problem is the main issue from analyzing the OERs. Korean nuclear power plant operators will work in UAE and they will operate the NPPs with other countries' operators and managers. Therefore they will have to use English when they communicate each other. The purpose of this paper is to confirm how much operators get stress and how much accuracy is declined when operators communicate together in English. Reducing human error is quite important to make nuclear power plants safety. As mental workload of human operator is increased, operators get more stress, then the probability of occurring human error may be increased. It will affect bad influence to nuclear power plants safety. There are many factors to make mental workload increased. We focused on communication problem which is a key factor of the increasing mental workload because many Korean operators will work in UAE nuclear power plants and they may work together with UAE operators. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To find the impact of how much English affects the operators' workload, we did two cases of experiments; one is experiment for diagnosis and the other is experiment for execution.

  14. Experience in integrating the operator contributions in the PRA of actual operating plants

    Potash, L.M.; Stewart, M.; Dietz, P.E.; Lewis, C.M.; Dougherty, E.M. Jr.

    1982-01-01

    While working on the human factors' portion of the Oconee Probabilistic Risk Assessment, we identified several major problems that inhibit any effort to handle operator error in PRAs. The approaches we developed should help to direct future efforts in dealing with these problems

  15. Control valve friction operational experience at Darlington NGD

    Speer, B.

    1995-01-01

    Proper installation of valve packing is an important part of ensuring that control valves operate as intended. Darlington NGD has developed a Valve Packing Program. This program combined with valve diagnostics has enabled the station to ensure that the operability of control valves is maintained after repacking. This paper outlines the process that is used for this. (author)

  16. early experience of operative treatment of pelvic and acetabular

    Objective: To review early post-operative results of pelvic and acetabular fracture intern al fixation. Design: ... 600 needing operative treatment annually. ... Infection was controlled with debridement and antibiotics. All the patients in the study returned to their work except one who has yet to do so 5 months after his injury.

  17. Operating experience with the Fermilab 500-GeV accelerator

    Urban, G.S.; Gannon, J.C.

    1977-01-01

    The Fermilab accelerator has been operating for more than four years. It has been improved so that it is now capable of operating at an energy of 500 GeV and an intensity in excess of 2.0 x 10 13 protons per pulse. The accelerator is manned on a 24 hour a day basis by an operating team of five persons. This is possible in part, because almost all of the hardware systems have status monitoring and control through an advanced computer control system. A discussion is given of the operation of the accelerator with emphasis on person to machine interface, operator training techniques used at Fermilab, and the keeping of records and reliability information

  18. Operating experience and performance at Narora Atomic Power Station

    Mittal, Subhash; Gupta, J.P.

    1998-01-01

    Narora Atomic Power Station consists of two units of 220 MWe capacity each. These are Pressurized Heavy Water Reactors, fuelled by natural uranium, moderated and cooled by heavy water. The Station is owned by Nuclear Power Corporation of India Ltd., which is responsible for design, construction, commissioning, and operation of all nuclear power stations in the country. NAPS was the first opportunity to apply operating experiences in design, keeping in view the evolving safety and seismicity requirements, ease of maintenance, inservice inspection needs, improved construction ability and standardization. Both the units of NAPS are having improved safety standards of current international levels. All the equipment are indigenous with improved quality and reliability. The first unit of the station went critical in March 1989 and synchronized to the grid in July 1989. The second units followed with its criticality in October 1991 and synchronization in January 1992. Considering the initial stabilizing period, the performance of both units of NAPS has progressively improved over the years. The annual capacity factor for NAPS - 1 was 90.01% and for NAPS - 2 was 89.01% for the financial year 1997-1998. This paper presents an analysis of the performance during the last three years and measures taken to improve it. The stated enhanced performance could be achieved by improvement in human performance by training/re-training, scrupulous monitoring and review of equipment/systems, institution of adequate procedure and ensuring their adherence. (authors)

  19. Canadian CANDU fuel development program and recent fuel operating experience

    Lau, J.H.K.; Inch, W.W.R.; Cox, D.S.; Steed, R.G.; Kohn, E.; Macici, N.N.

    1999-01-01

    This paper reviews the performance of the CANDU fuel in the Canadian CANDU reactors in 1997 and 1998. The operating experience demonstrates that the CANDU fuel has performed very well. Over the 2-year period, the fuel-bundle defect rate for all bundles irradiated in the Canadian CANDU reactors has remained very low, at between 0.006% to 0.016%. On a fuel element basis, this represents an element defect rate of less than about 0.0005%. One of the reasons for the good fuel performance is the support provided by the Canadian fuel research and development programs. These programs address operational issues and provide evolutionary improvements to the fuel products. The programs consist of the Fuel Technology Program, funded by the CANDU Owners Group, and the Advanced Fuel and Fuel Cycles Technology Program, funded by Atomic Energy of Canada Ltd. These 2 programs, which have been in place for many years, complement each other by sharing expert resources and experimental facilities. This paper describes the programs in 1999/2000, to provide an overview of the scope of the programs and the issues that these programs address. (author)

  20. Operational Experience with the ATLAS Pixel Detector at LHC

    Keil, M

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus crucial for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via front-end chips bump-bonded to 1744 n-on-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including calibration procedures, detector performance and measurements of radiation damage. The detector performance is excellent: more than 95% of the pixels are operational, noise occupancy and hit efficiency exceed the des...

  1. The ATLAS Tier-0: Overview and operational experience

    Elsing, Markus; Goossens, Luc; Nairz, Armin; Negri, Guido

    2010-01-01

    Within the ATLAS hierarchical, multi-tier computing infrastructure, the Tier-0 centre at CERN is mainly responsible for prompt processing of the raw data coming from the online DAQ system, to archive the raw and derived data on tape, to register the data with the relevant catalogues and to distribute them to the associated Tier-1 centers. The Tier-0 is already fully functional. It has been successfully participating in all cosmic and commissioning data taking since May 2007, and was ramped up to its foreseen full size, performance and throughput for the cosmic (and short single-beam) run periods between July and October 2008. Data and work flows for collision data taking were exercised in several 'Full Dress Rehearsals' (FDRs) in the course of 2008. The transition from an expert to a shifter-based system was successfully established in July 2008. This article will give an overview of the Tier-0 system, its data and work flows, and operations model. It will review the operational experience gained in cosmic, commissioning, and FDR exercises during the past year. And it will give an outlook on planned developments and the evolution of the system towards first collision data taking expected now in late Autumn 2009.

  2. Primary water chemistry of VVERs-operating experience

    Kysela, Jan; Zmitko, Milan; Petrecky, Igor

    1998-01-01

    VVER units are operated in mixed boron-potassium-ammonia water chemistry. Several modifications of the water chemistry, differing in boron-potassium co-ordination and in the way how hydrogen concentration is produced and maintain in the coolant, is used. From the operational experience point of view VVER units do not show any significant problems connected with the primary coolant chemistry. The latest results indicate that dose rate levels are slowly returning to the former ones. An improvement of the radiation situation observed last two years is supported by the surface activity measurements. However, the final conclusion on the radiation situation can be made only after evaluation of the several following cycles. Further investigation is also needed to clarify a possible effect of modified water chemistry and shut-down chemistry on radioactivity build-up and dose rate level at Dukovany units. Structure materials composition has a significant effect on radiation situation in the units. It concerns mainly of cobalt content in SG material. There is no clear evidence of possible effect of the SG shut-down regimes on the radiation situation in the units even if the dose rate and surface activity data show wide spread for the individual reactor loops. (S.Y.)

  3. The ATLAS Tier-0 Overview and operational experience

    Elsing, M; Nairz, A; Negri, G

    2010-01-01

    Within the ATLAS hierarchical, multi-tier computing infrastructure, the Tier-0 centre at CERN is mainly responsible for prompt processing of the raw data coming from the online DAQ system, to archive the raw and derived data on tape, to register the data with the relevant catalogues and to distribute them to the associated Tier-1 centers. The Tier-0 is already fully functional. It has been successfully participating in all cosmic and commissioning data taking since May 2007, and was ramped up to its foreseen full size, performance and throughput for the cosmic (and short single-beam) run periods between July and October 2008. Data and work flows for collision data taking were exercised in several "Full Dress Rehearsals" (FDRs) in the course of 2008. The transition from an expert to a shifter-based system was successfully established in July 2008. This article will give an overview of the Tier-0 system, its data and work flows, and operations model. It will review the operational experience gained in cosmic, c...

  4. The ATLAS Tier-0: Overview and operational experience

    Elsing, Markus; Goossens, Luc; Nairz, Armin; Negri, Guido

    2010-04-01

    Within the ATLAS hierarchical, multi-tier computing infrastructure, the Tier-0 centre at CERN is mainly responsible for prompt processing of the raw data coming from the online DAQ system, to archive the raw and derived data on tape, to register the data with the relevant catalogues and to distribute them to the associated Tier-1 centers. The Tier-0 is already fully functional. It has been successfully participating in all cosmic and commissioning data taking since May 2007, and was ramped up to its foreseen full size, performance and throughput for the cosmic (and short single-beam) run periods between July and October 2008. Data and work flows for collision data taking were exercised in several "Full Dress Rehearsals" (FDRs) in the course of 2008. The transition from an expert to a shifter-based system was successfully established in July 2008. This article will give an overview of the Tier-0 system, its data and work flows, and operations model. It will review the operational experience gained in cosmic, commissioning, and FDR exercises during the past year. And it will give an outlook on planned developments and the evolution of the system towards first collision data taking expected now in late Autumn 2009.

  5. Development, operating experience and future plan of ABWR in Japan

    Ujihara, N.

    2001-01-01

    From 1974 to 1978 nuclear power plants' capacity factor decreased to a low level at the Tokyo Electric Power Company (TEPCO) for stress corrosion cracking of stainless steal pipe, thermal fatigue crack of feed water spurger and vibration trouble of LPRM, etc. So, for improving that situation, we gathered the most useful BWR technology in the world at that time and we started the ABWR project to develop an ideal BWR. The goals of this development were: (1) Enhanced safety and reliability; (2) Reduced occupational radiation exposure and radioactive waste; (3) Enhanced operability and maneuverability; and (4) Improved economy. Significant improvements were induced by the adoption of the reactor internal pump, fine motion control rod drive mechanism, integral type reinforced concrete containment vessel and digital control system. After about 10 years R and D, we succeeded in the development of the compact and economic plant, ABWR (1356MW(e)) whose building volume had been reduced to 76%, compared with the previous BWR (1100MW(e)). The construction of Kashiwazaki-Kariwa Nuclear Power Plant unit No. 6, which is the first ABWR plant in the world, was started September 1991, and that of unit No. 7 was started in February 1992. We used effective construction methods, such as large block construction method and all weather construction method, to shorten the construction duration from first concrete to commercial operation start to 51.5 months. The commercial operation start of Kashiwazaki-Kariwa Nuclear Power Plant unit No. 6 was November 1996 and that of unit No. 7 was July 1997. After that, unit No. 6 had three times the annual outage and unit No. 7 had two times the annual outage. Both plants have good operating experiences. From commercial operation start to end of August 2000, the capacity factor of unit No. 6 is 86.4% and that of unit No. 7 is 86.9%. Now, in Taiwan, ABWR plants are under construction at Lungmen unit No. 1 and 2. In Japan, ABWR plants are under

  6. Mechanic- and hydraulic shock-absorbers - layout, construction, operation experience

    Kluge, M.

    1981-01-01

    The problem lies in the protection of the flexible supported power plant components against undesired sudden movements. Various shock absorbing systems are at disposal in this case: Mechanical and hydraulic shock absorbers, whose functioning systems are shown in figures. The operation experience showed a series of deficiencies, as demonstrated on various figures. In order to avoid them, some important recommendations are given. Requirements and layout are demonstrated according to todays' state-of-the-art. The admissible stresses, resulting from the summary of various specifications for the analytical evidence will be described. Development and construction will be explained in detail by means of pictures with cross sections of original shock absorbers. Todays' construction characteristics will be summarized. The final remark includes a request for generally valid guidelines. (orig.) [de

  7. Operating experience with ion exchanger beds in CIRUS

    Acharya, V.N.; Hajra, P.

    1977-01-01

    Operating experience with the ion exchanger beds in CIRUS reactor is narrated. Ion exchangers are provided for demineralisation of make up water and purification of closed loop water circuits. Exhaustion of resin is assessed on the basis of CO 2 concentration in the helium vent gas of the heavy water system. It is recommended that valves in the resin columns for rod handling bays be located outside the enclosure and each bed to reduce man-rem consumption during maintenance. Repeated backwash of the bed reduces chocking of water space with resin fines. Preventive maintenance avoids leakage past valves. Active resin from the resin beds is removed by hydraulic transfer method. (M.G.B.)

  8. Operating experience of the EBR-II steam generating system

    Buschman, H.W.; Penney, W.H.; Quilici, M.D.; Radtke, W.H.

    1981-01-01

    The Experimental Breeder Reactor II (EBR-II) is a Liquid Metal Fast Breeder Reactor (LMFBR) with integrated power producing capability. Superheated steam is produced by eight natural circulation evaporators, two superheaters, and a conventional steam drum. Steam throttle conditions are 438 C (820 F) and 8.62 MPa (1250 psi). The designs of the evaporators and superheaters are essentially identical; both are counterflow units with low pressure nonradioactive sodium on the shell side. Safety and reliability are maximized by using duplex tubes and tubesheets. The performance of the system has been excellent and essentially trouble free. The operating experience of EBR-II provides confidence that the technology can be applied to commercial LMFBR's for an abundant supply of energy for the future. 5 refs

  9. Operational experience of the fuel cleaning facility of Joyo

    Mukaibo, R.; Matsuno, Y.; Sato, I.; Yoneda, Y.; Ito, H.

    1978-01-01

    Spent fuel assemblies in 'Joyo', after they are taken out of the core, are taken to the Fuel Cleaning Facility in the reactor service building and sodium removal is done. The cleaning process is done by cooling the assembly with argon gas, steam charging and rinsing by demineralized water. Deposited sodium was 50 ∼ 60 g per assembly. The sodium and steam reaction takes about 15 minutes to end and the total time the fuel is placed in the pot is about an hour. The total number of assemblies cleaned in the facility was 95 as of November 1977. In this report the operational experience together with discussions of future improvements are given. (author)

  10. Operational Experience from LCLS-II Cryomodule Testing

    Wang, Renzhuo [Fermilab; Hansen, Benjamin [Fermilab; White, Michael [Fermilab; Hurd, Joseph [Fermilab; Atassi, Omar Al [Fermilab; Bossert, Richard [Fermilab; Pei, Liujin [Fermilab; Klebaner, Arkadiy [Fermilab; Makara, Jerry [Fermilab; Theilacker, Jay [Fermilab; Kaluzny, Joshua [Fermilab; Wu, Genfa [Fermilab; Harms, Elvin [Fermilab

    2017-07-01

    This paper describes the initial operational experience gained from testing Linac Coherent Light Source II (LCLS-II) cryomodules at Fermilab’s Cryomodule Test Facility (CMTF). Strategies for a controlled slow cooldown to 100 K and a fast cooldown past the niobium superconducting transition temperature of 9.2 K will be described. The test stand for the cryomodules at CMTF is sloped to match gradient in the LCLS-II tunnel at Stanford Linear Accelerator (SLAC) laboratory, which adds an additional challenge to stable liquid level control. Control valve regulation, Superconducting Radio-Frequency (SRF) power compensation, and other methods of stabilizing liquid level and pressure in the cryomodule 2.0 K SRF cavity circuit will be discussed. Several different pumping configurations using cold compressors and warm vacuum pumps have been used on the cryomodule 2.0 K return line and the associated results will be described.

  11. Operational experience from LCLS-II cryomodule testing

    Wang, R.; Hansen, B.; White, M.; Hurd, J.; Atassi, O. Al; Bossert, R.; Pei, L.; Klebaner, A.; Makara, J.; Theilacker, J.; Kaluzny, J.; Wu, G.; Harms, E.

    2017-12-01

    This paper describes the initial operational experience gained from testing Linac Coherent Light Source II (LCLS-II) cryomodules at Fermilab’s Cryomodule Test Facility (CMTF). Strategies for a controlled slow cooldown to 100 K and a fast cooldown past the niobium superconducting transition temperature of 9.2 K will be described. The test stand for the cryomodules at CMTF is sloped to match gradient in the LCLS-II tunnel at Stanford Linear Accelerator (SLAC) laboratory, which adds an additional challenge to stable liquid level control. Control valve regulation, Superconducting Radio-Frequency (SRF) power compensation, and other methods of stabilizing liquid level and pressure in the cryomodule 2.0 K SRF cavity circuit will be discussed. Several different pumping configurations using cold compressors and warm vacuum pumps have been used on the cryomodule 2.0 K return line and the associated results will be described.

  12. Experiments simulation and design to set traffic lights operation rules

    Jimenez Garcia, J.A.

    2016-07-01

    In this paper it is used the experimental design to minimize the travel time of motor vehicles, in one of the most important avenues of Celaya City in Guanajuato, Mexico, by means of optimal synchronization of existing traffic lights. In the optimization process three factors are considered: the traffic lights’ cycle times, the synchrony defined as stepped, parallel and actual, and speed limit, each one with 3 evaluation levels. The response variables to consider are: motor vehicles’ travel time, fuel consumption and greenhouse effect gas (CO2) emissions. The different experiments are performed using the simulation model developed in the PTV-VISSIM software, which represents the vehicle traffic system. The obtained results for the different proposed scenarios allow to find proper levels at which the vehicle traffic system must be operated in order to improve mobility, to reduce contamination rates and decrease the fuel consumption for the different motor vehicles that use the avenue. (Author)

  13. Operational experience of the fuel cleaning facility of Joyo

    Mukaibo, R; Matsuno, Y; Sato, I; Yoneda, Y; Ito, H [O-arai Engineering Centre, PNC, Ibaraki-ken, Tokio (Japan)

    1978-08-01

    Spent fuel assemblies in 'Joyo', after they are taken out of the core, are taken to the Fuel Cleaning Facility in the reactor service building and sodium removal is done. The cleaning process is done by cooling the assembly with argon gas, steam charging and rinsing by demineralized water. Deposited sodium was 50 {approx} 60 g per assembly. The sodium and steam reaction takes about 15 minutes to end and the total time the fuel is placed in the pot is about an hour. The total number of assemblies cleaned in the facility was 95 as of November 1977. In this report the operational experience together with discussions of future improvements are given. (author)

  14. Operating experience review in development of SMART MMIS

    Suh, S. M.; Jang, G. S.; Lee, J. G.; Park, G. O.; Ko, J. H.

    2004-01-01

    We have developed HFE(Human Factors Engineering) program plan for the purpose of implementing man-machine interface system in SMART plant systematically. Elements of the plan are compatible to those of NUREG-0711, Rev.1, and OER(Operating Experience Review) is one of them. The main purpose of conducting an OER as part of HFE review is to identify HFE-related safety issues. If identified, design alternatives are carefully reviewed and selected as the way of resolution for those issues. The performing model of OER is described in this paper, showing a series of works must be done to identify and resolve HFE-related issues within the scope of SMART HFE works. Then two key issues and design alternatives resolving them are presented for examples

  15. Savannah River Site Operating Experience with Transuranic (TRU) Waste Retrieval

    Stone, K.A.; Milner, T.N.

    2006-01-01

    Drums of TRU Waste have been stored at the Savannah River Site (SRS) on concrete pads from the 1970's through the 1980's. These drums were subsequently covered with tarpaulins and then mounded over with dirt. Between 1996 and 2000 SRS ran a successful retrieval campaign and removed some 8,800 drums, which were then available for venting and characterization for WIPP disposal. Additionally, a number of TRU Waste drums, which were higher in activity, were stored in concrete culverts, as required by the Safety Analysis for the Facility. Retrieval of drums from these culverts has been ongoing since 2002. This paper will describe the operating experience and lessons learned from the SRS retrieval activities. (authors)

  16. Operational experience of stainless steels in seawater-cooled systems

    Henriksson, S.

    1981-06-01

    A study has been made of chiefly Swedish and Finnish operational experience of stainless steel in seawater and brackish water. A report is given on 23 typical cases, behind which in actual fact a considerably larger number of individual practical cases are concealed. The answer to the primary question why a standard steel of type SS 2343 (AISI 316) sometimes, contrary to expectation, remains unattacked by local corrosion is that there is usually spontaneous cathodic protection by other less noble components of carbon steel, cast iron or some copper alloy in direct contact with the stainless steel. The study confirms in other respects the adverse effect of residual oxides after welding and the beneficial of low temperature, high continuous waterflow and periodic cleaning, and of rinsing with fresh water during out-of service periods. It also verifies the additional advantages of the new high-alloy special steels which have begun to be marketed in recent years for seawater applications. (author)

  17. Design and operational experience with a portable tritium cleanup system

    Maienschein, J.L.; Wilson, S.W.; Garcia, F.

    1991-06-01

    We built a portable tritium cleanup system to scavenge tritium from contaminated gases in any tritium-containing system in the LLNL Tritium Facility. The cleanup system uses standard catalytic oxidation of tritium to water followed by water removal with a molecular sieve dryer. The cleanup unit, complete with instrumentation, is contained in a portable cart that is rolled into place and connected to the apparatus to be cleaned. The cleanup systems is effective, low-tech, simple, and reliable. The nominal flow rate of the system is 30 liters/minute, and the decontamination factor is > 1000. In this paper we will show design information on our portable cleanup system, and will discuss our operational experience with it over the past several years

  18. U-2g0 cyclotron operational experience and improvement

    Gigal, B.N.; Gul'bekyan, G.G.; Kozlov, S.I.; Oganesyan, R.Ts.

    1983-01-01

    Brief description of main syste's of the U-200 isochronous 2-m cyclotron put into opera ion in 1968 is given and its operational characteristics a e presented. The cyclotron is used for conducting inve tigations in the field of nuclear physics. Ions from d uterium to argon have been accelerated in the cyclotro'. Annual time of target irradiation constitutes 2000-4000. The specific features of the cyclotron are: high l vel of a magnetic field (of about 20 kOe), possibili y of acceleration of ions with different mass-to-charge ratio a low correcting winding power, simple and high-e fective beam extraction by the method of charge exchange on a thin target allowing to vary smoothly energy of extracted ons. An experience in the U-200 cyclotron development and o eration is used as the basis for designing and choosing basic parameters of the U-200P, U-250, U-400 heavy ion cyclotrons

  19. Experiment of a centrifugal pump during changing speed operation

    Yuan, H J; Wu, Y L; Liu, S H; Shao, J

    2012-01-01

    In this paper, a method of changing rotational speed of impeller periodically as the pulsatile working condition is developed to realize pulse outputs both of flow discharge and of head for a centrifugal pump through experiment. The performance of the centrifugal pump under pulsatile working operation condition is measured which indicates this model pump could produce desired pulse flow under such condition. Flow patterns at four testing points under pulsatile conditions are obtained by means of the particle image velocimetry (PIV) technology both with laser induced fluorescence (LIF) particles and refractive index matched (RIM) fluid. Results of PIV measurement show the distributions of velocity, streamlines, and the principal Reynolds normal stress (PRNS). Under the design flow rate condition, the relative velocity in the blade channel distributes smoothly and decreases from inlet to exit. And at the impeller exit, the relative velocity is lower close to suction side than that near pressure side of blade in most of blade channels.

  20. MOX and UOX PWR fuel performances EDF operating experience

    Provost, Jean-Luc; Debes, Michel

    2005-01-01

    Based on a large program of experimentations implemented during the 90s, the industrial achievement of new FAs designs with increased performances opens up new prospects. The currently UOX fuels used on the 58 EDF PWR units are now authorized up to a maximum FA burn-up of 52 GWd/t with a large experience from 45 to 50 GWd/t. Today, the new products, along with the progress made in the field of calculation methods, still enable to increase further the fuel performances with respect to the safety margins. Thus, the conditions are met to implement in the next years new fuel managements on each NPPs series of the EDF fleet with increased enrichment (up to 4.5%) and irradiation limits (up to 62 GWd/t). The recycling of plutonium is part of EDF's reprocessing/recycling strategy. Up to now, 20 PWR 900 MW reactors are managed in MOX hybrid management. The feedback experience of 18 years of PWR operation with MOX is satisfactory, without any specific problem regarding manoeuvrability or plant availability. EDF is now looking to introduce MOX fuels with a higher plutonium content (up to 8.6%) equivalent to natural uranium enriched to 3.7%. It is the goal of the MOX Parity core management which achieve balance of MOX and UOX fuel performance with a significant increase of the MOX average discharge burn-up (BU max: 52 GWd/t for MOX and UOX). The industrial maturity of new FAs designs, with increased performances, allows the implementation in the next years of new fuel managements on each NPPs series of the EDF fleet. The scheduling of the implementation of the new fuel managements on the PWRs fleet is a great challenge for EDF, with important stakes: the nuclear KWh cost decrease with the improvement of the plant operation performance. (author)

  1. EDF/EPRI collaborative program on operator reliability experiments

    Villemeur, A.; Meslin, T.; Mosneron, F.; Worledge, D.H.; Joksimovich, V.; Spurgin, A.J.

    1988-01-01

    Electricite de France (EDF) and Electric Power Research Institute (EPRI) have been involved in human reliability studies over the last few years, in the context of improvements in human reliability assessment (HRA) methodologies, and have been following a systematic process since 1982 which consists of addressing the following five ingredients: - First, classify human interactions into a limited number of classes. - Second, introduce an acceptable framework to organize the application of HRA to PRA studies. - Third, select approach(es) to quantification. - Fourth, test promising models. - Fifth, establish an appropriate data base for tested model(s) with regard to specific applications. EPRI has just recently completed Phase I of the fourth topic. This primarily focused on testing the fundamental hypotheses behing the human cognitive reliability (HCR) correlation, using power plant simulators. EDF has been carrying out simulator studies since 1980, both for man-machine interface validation and HRA data collection. This background of experience provided a stepping stone for the EPRI project. On the other hand, before 1986, EDF had mainly been concentrating on getting qualitative insights from the tests and lacked experience in quantitative analysis and modeling, while EPRI had made advances in this latter area. Before the EPRI Operator Reliability Experiments (ORE) project was initiated, it was abundantly clear to EPRI and EDF that cooperation between the two could be useful and that both parties could gain from the cooperation

  2. Fast Flux Test Facility sodium pump operating experience - mechanical

    Buonamici, R.

    1987-11-01

    The Heat Transport System (HTS) pumps were designed, fabricated, tested, and installed in the Fast Flux Test Facility (FFTF) Plant during the period from September 1970 through July 1977. Since completion of the installation and sodium fill in December 1978, the FFTF Plant pumps have undergone extensive testing and operation with HTS testing and reactor operation. Steady-state hydraulic and mechanical performances have been and are excellent. In all, FFTF primary and secondary pumps have operated in sodium for approximately 75,000 hours and 79,000 hours, respectively, to August 24, 1987

  3. Operating experience with decommissioning of underground components, USA

    2006-01-01

    In the USA there has over the years been widespread use of underground piping and tank storage systems, as well as use of other storage vaults and miscellaneous underground storage systems. In most instances these systems are associated with other operating facilities such as large nuclear facilities. There has been considerable experience over the last 60 years in the design, installation, operation and decommissioning of these radioactive waste handling and storage structures and systems. Legislation was enacted in the 1980s that required extensive upgrades to existing systems, with newly installed systems being required to meet stringent installation, operation and removal requirements. This has had an impact on the use of some of these underground systems. One major problem with many of these systems is to gauge the integrity of the systems after they have been in operation for many years and to accurately determine whether they have leaked or not. Depending on the results of these investigations, the next question is whether these systems even need to be excavated or if they can be dispositioned in place rather than expending a large amount of effort to excavate them and remove the materials in question to a disposal site for final dispositioning. In some areas this is possible while in others excavation is required. Over the years that nuclear facilities have been operational in the USA, advantage has been taken of the fact that the earth serves as a good location for emplacement of otherwise obtrusive (or even less aesthetically pleasing) structures. These structures are also still clearly able to support the useful mission they were always intended to fulfil. This arrangement also serves as a structural feature favourable to minimizing radiation exposure levels emanating from systems and components containing radioactive materials. In some cases, embedding of various components such as tanks, pits, vaults, pipes and ducting was an easy way to avoid these

  4. Operating experience with Beloyarsk fast reactor BN600 NPP

    Saraev, O.M.

    2000-01-01

    The main results of the seventeen-year operation of the BN600 Nuclear Power Plant are considered. The principal backfittings of the main BN600 Power Plant equipment are presented and summarised. (author)

  5. FFTF operating experience with sodium natural circulation: slides included

    Burke, T.M.; Additon, S.L.; Beaver, T.R.; Midgett, J.C.

    1981-01-01

    The Fast Flux Test Facility (FFTF) has been designed for passive, back-up, safety grade decay heat removal utilizing natural circulation of the sodium coolant. This paper discusses the process by which operator preparation for this emergency operating mode has been assured, in paralled with the design verification during the FFTF startup and acceptance testing program. Over the course of the test program, additional insights were gained through the testing program, through on-going plant analyses and through general safety evaluations performed throughout the nuclear industry. These insights led to development of improved operator training material for control of decay heat removal during both forced and natural circulation as well as improvements in the related plant operating procedures.

  6. FFTF operating experience with sodium natural circulation: slides included

    Burke, T.M.; Additon, S.L.; Beaver, T.R.; Midgett, J.C.

    1981-01-01

    The Fast Flux Test Facility (FFTF) has been designed for passive, back-up, safety grade decay heat removal utilizing natural circulation of the sodium coolant. This paper discusses the process by which operator preparation for this emergency operating mode has been assured, in paralled with the design verification during the FFTF startup and acceptance testing program. Over the course of the test program, additional insights were gained through the testing program, through on-going plant analyses and through general safety evaluations performed throughout the nuclear industry. These insights led to development of improved operator training material for control of decay heat removal during both forced and natural circulation as well as improvements in the related plant operating procedures

  7. CERN's LEIR Digital LLRF : system overview and operational experience

    Angoletta, ME; Blas, A; Bracke, E; Butterworth, A; Dubouchet, F; Findlay, A; Pedersen, F; Sanchez-Quesada, J

    2010-01-01

    The Low Energy Ion Ring (LEIR) is an accumulation and acceleration ring in the Large Hadron Collider (LHC) ion injector chain. After its successful start in 2005, it has been running in three operational campaigns. The LEIR low-level RF (LLRF) system is the first all-digital system to operate in a CERN circular machine. Its capabilities include beam control tasks as well as dual-harmonic cavity voltage/phase servoing. All the system’s control parameters are fully configurable, remotely and in-between cycles; extensive built-in observation capabilities and diagnostics are available. The system is flexible, powerful and extremely reliable. This paper outlines the main building blocks and operational features, along with results obtained during the first years of operation.

  8. Experiments at the Soudan mine: operating and proposed

    Shupe, M.A.

    1981-01-01

    We report on the initial operation of a 30 ton dense calorimeter and on the proposed construction of a 1000 ton calorimeter at the Soudan mine in northern Minnesota - both optimized for the detection of proton decay

  9. Operational Experience with the Frontier System in CMS

    Blumenfeld, Barry; Dykstra, Dave; Kreuzer, Peter; Du Ran; Wang Weizhen

    2012-01-01

    The Frontier framework is used in the CMS experiment at the LHC to deliver conditions data to processing clients worldwide, including calibration, alignment, and configuration information. Each central server at CERN, called a Frontier Launchpad, uses tomcat as a servlet container to establish the communication between clients and the central Oracle database. HTTP-proxy Squid servers, located close to clients, cache the responses to queries in order to provide high performance data access and to reduce the load on the central Oracle database. Each Frontier Launchpad also has its own reverse-proxy Squid for caching. The three central servers have been delivering about 5 million responses every day since the LHC startup, containing about 40 GB data in total, to more than one hundred Squid servers located worldwide, with an average response time on the order of 10 milliseconds. The Squid caches deployed worldwide process many more requests per day, over 700 million, and deliver over 40 TB of data. Several monitoring tools of the tomcat log files, the accesses of the Squids on the central Launchpad servers, and the availability of remote Squids have been developed to guarantee the performance of the service and make the system easily maintainable. Following a brief introduction of the Frontier framework, we describe the performance of this highly reliable and stable system, detail monitoring concerns and their deployment, and discuss the overall operational experience from the first two years of LHC data-taking.

  10. Operational experience with the CMS Data Acquisition System

    CERN. Geneva

    2012-01-01

    The data-acquisition (DAQ) system of the CMS experiment at the LHC performs the read-out and assembly of events accepted by the first level hardware trigger. Assembled events are made available to the high-level trigger (HLT), which selects interesting events for offline storage and analysis. The system is designed to handle a maximum input rate of 100 kHz and an aggregated throughput of 100 GB/s originating from approximately 500 sources and 10^8 electronic channels. An overview of the architecture and design of the hardware and software of the DAQ system is given. We report on the performance and operational experience of the DAQ and its Run Control System in the first two years of collider run of the LHC, both in proton-proton and Pb-Pb collisions. We present an analysis of the current performance, its limitations, and the most common failure modes and discuss the ongoing evolution of the HLT capability needed to match the luminosity ramp-up of the LHC.

  11. Variability in Resident Operative Hand Experience by Specialty.

    Silvestre, Jason; Lin, Ines C; Levin, L Scott; Chang, Benjamin

    2018-01-01

    Recent attention has sought to standardize hand surgery training in the United States. This study analyzes the variability in operative hand experience for orthopedic and general surgery residents. Case logs for orthopedic and general surgery residency graduates were obtained from the American Council of Graduate Medical Education (2006-2007 to 2014-2015). Plastic surgery case logs were not available for comparison. Hand surgery case volumes were compared between specialties with parametric tests. Intraspecialty variation in orthopedic surgery was assessed between the bottom and top 10th percentiles in procedure categories. Case logs for 9605 general surgery residents and 5911 orthopedic surgery residents were analyzed. Orthopedic surgery residents performed a greater number of hand surgery cases than general surgery residents ( P < .001). Mean total hand experience ranged from 2.5 ± 4 to 2.8 ± 5 procedures for general surgery residents with no reported cases of soft tissue repairs, vascular repairs, and replants. Significant intraspecialty variation existed in orthopedic surgery for all hand procedure categories (range, 3.3-15.0). As the model for hand surgery training evolves, general surgeons may represent an underutilized talent pool to meet the critical demand for hand surgeon specialists. Future research is needed to determine acceptable levels of training variability in hand surgery.

  12. Operational Experience with the Frontier System in CMS

    Blumenfeld, Barry; Dykstra, Dave; Kreuzer, Peter; Du, Ran; Wang, Weizhen

    2012-12-01

    The Frontier framework is used in the CMS experiment at the LHC to deliver conditions data to processing clients worldwide, including calibration, alignment, and configuration information. Each central server at CERN, called a Frontier Launchpad, uses tomcat as a servlet container to establish the communication between clients and the central Oracle database. HTTP-proxy Squid servers, located close to clients, cache the responses to queries in order to provide high performance data access and to reduce the load on the central Oracle database. Each Frontier Launchpad also has its own reverse-proxy Squid for caching. The three central servers have been delivering about 5 million responses every day since the LHC startup, containing about 40 GB data in total, to more than one hundred Squid servers located worldwide, with an average response time on the order of 10 milliseconds. The Squid caches deployed worldwide process many more requests per day, over 700 million, and deliver over 40 TB of data. Several monitoring tools of the tomcat log files, the accesses of the Squids on the central Launchpad servers, and the availability of remote Squids have been developed to guarantee the performance of the service and make the system easily maintainable. Following a brief introduction of the Frontier framework, we describe the performance of this highly reliable and stable system, detail monitoring concerns and their deployment, and discuss the overall operational experience from the first two years of LHC data-taking.

  13. Summary of operating experience in Swiss nuclear power plants 1993

    1994-07-01

    In 1993 the Swiss nuclear power plants produced their third highest combined annual output. The contribution to the total electricity generation in the country was close to 37%. Replacement of the steam generators in Beznau Unit 1 resulted in a longer than usual annual outage. For the other four units the availability figures were close to, or exceeded, those of previous years. The energy utilization was, however, lowered due to load reduction in autumn resulting from unusually high production by the hydro-electric power plants. The steam generator replacement at Beznau enabled an increase in electrical power of about 2% without increase in reactor power. With the approval of the Swiss government in December 1992, the output of the Muehleberg power plant was increased in two stages by a total of 10%. The application for an unlimited operating license for Beznau Unit 2, and for a power uprate at the Leibstadt power plant, are still pending. The average number of scrams at the Swiss plants remained stable, at less than one scram per reactor year. As a result of experience in the Swedish nuclear power plant at Barsebaeck, the suction strainers of the emergency core cooling systems of the boiling water reactors at Muehleberg and Leibstadt were replaced by strainers with larger surface areas. The re-inspection of crack indications previously detected in the core shroud of the Muehleberg reactor and the penetration tubes in the reactor pressure vessel closure head of Beznau revealed no growth during the intervening operating periods. Following the completion of installation activities during the annual outages at Beznau Unit 1, Goesgen and Leibstadt, all Swiss nuclear power plants are now equipped with filtered containment venting systems. (author) figs., tabs

  14. Operational and troubleshooting experiences in the SST-1 cryogenic system

    Mahesuria, G.; Panchal, P.; Panchal, R.; Patel, R.; Sonara, D.; Gupta, N. C.; Srikanth, G. L. N.; Christian, D.; Garg, A.; Bairagi, N.; Patel, K.; Shah, P.; Nimavat, H.; Sharma, R.; Patel, J. C.; Tank, J.; Tanna, V. L.; Pradhan, S.

    2014-01-01

    Recently, the cooldown and current charging campaign have been carried out towards the demonstration of the first successful plasma discharge in the steady state superconducting Tokomak (SST-1). The SST-1 machine consists of cable-in-conduit wound superconducting toroidal as well as poloidal coils, cooled using 1.3 kW at 4.5 K helium refrigerator -cum- liquefier (HRL) system. The cryo system provides the two-phase helium at 0.13 MPa at 4.5 K as well as forced-flow pressurized helium at 0.4 MPa and in addition to 7 g-s-1 liquefaction capacity required for the current leads and other cold mass at 4.5 K. The entire integrated cold masses having different thermo hydraulic resistances cooled with the SST-1 HRL in optimised process parameters. In order to maintain different levels of temperatures and to facilitate smooth and reliable cooldown, warm-up, normal operations as well as to handle abnormal events such as, quench or utilities failures etc., exergy efficient process are adopted for the helium refrigerator-cum-liquefier (HRL) with an installed equivalent capacity of 1.3 kW at 4.5 K. Using the HRL, the cold mass of about 40 tons is being routinely cooled down from ambient temperature to 4.5 K with an average cooldown rate of 0.75 - 1 K-h-1. Long-term cryogenic stable conditions were obtained within 15 days in the superconducting coils and their connecting feeders. Afterwards, all of the cold mass is warmed-up in a controlled manner to ambient temperature. In this paper, we report the recent operational results of the cryogenic system during the first plasma discharge in SST-1 as well as the troubleshooting experiences of the cryogenic plant related hardware.

  15. Unguided bronchoscopic biopsy: Does yield increase with operator experience

    Tyagi Rahul

    2017-08-01

    Full Text Available Background Bronchoscopic Forceps biopsy (Endobronchial Biopsy (EBB and Trans Bronchial Lung Biopsy (TBLB are commonly performed for diagnosis in patients with endobronchial abnormalities or diffuse parenchymal involvement. As the operator gains experience his yield of various diagnostic bronchoscopic biopsies is expected to increase, however, no studies on the subject are available in literature. Aims To determine the effect of on- job experience on the yield of unguided bronchoscopic biopsies. Methods A total of 244 bronchoscopies were performed between Oct 2013 and Oct 2016. A retrospective analysis of all these bronchoscopies was undertaken. All patients who underwent biopsy were included in the study. Patients were divided into two groups with first group (Group A comprising of biopsies done between Oct 2013 to Apr 2015 and second group comprising biopsies done between May 2015 to Oct 2016 (Group B. The diagnostic yield in two groups was compared. Results Total 71 bronchoscopic biopsies were performed during Oct 2013 to Oct 2016. 36 patients were included in group A and 35 patients were included in group B. The groups were matched in demographic profile, clinical diagnosis, bronchoscopic findings and type of biopsy undertaken. The biopsy was diagnostic in 31 patient (43.6 per cent and nondiagnostic in 33 patients (46.4 per cent. There were 15 diagnostic biopsies in group A and 16 diagnostic biopsies in group B. The difference in the diagnostic biopsies between the two groups was not significant. Conclusion There was no significant impact of on job experience on diagnostic yield of biopsies. This may be due to adequate exposure during training leading to a diagnostic plateau being reached.

  16. First operational experience with the LHC machine protection system when operating with beam energies beyond the 100MJ range

    Assmann, R; Ferro-Luzzi, M; Goddard, B; Lamont, M; Schmidt, R; Siemko, A; Uythoven, J; Wenninger, J; Zerlauth, M

    2012-01-01

    The Large Hadron Collider (LHC) at CERN has made remarkable progress during 2011, surpassing its ambitious goal for the year in terms of luminosity delivered to the LHC experiments. This achievement was made possible by a progressive increase of beam intensities by more than 5 orders of magnitude during the first months of operation, reaching stored beam energies beyond the 100MJ range at the end of the year, less than a factor of 4 from the nominal design value. The correct functioning of the machine protection systems is vital during the different operational phases, for initial operation and even more when approaching nominal beam parameters where already a small fraction of the stored energy is sufficient to damage accelerator equipment or experiments in case of uncontrolled beam loss. Safe operation of the machine in presence of such high intensity proton beams is guaranteed by the interplay of many different systems: beam dumping system, beam interlocks, beam instrumentation, equipment monitoring, colli...

  17. Operation experience with the TRIGA reactor Wien 2004

    Boeck, H.; Villa, M.

    2004-01-01

    The TRIGA Mark-II reactor in Vienna is now in operation for more than 42 years. The average operation time is about 230 days per year with 90 % of this time at nominal power of 250 kW. The remaining 10 % operation time is used for students' training courses at low power level. Pulse operation is rather infrequent with about 5 to 10 pulses per year. The utilization of this facility is excellent, the number of students participating in practical exercises has strongly increased, and also training courses for outside groups such as the IAEA or for the 2004 Eugene Wigner Course are using the reactor, because it is the only TRIGA reactor remaining in Austria. Therefore, there is no need for decommissioning and it is intended to operate it as long as possible into the next decade. Nevertheless, in early 2004 it was decided to prepare a report on a decommissioning procedure for a typical TRIGA Mark II reactor which lists the volumes, the activity and the weight of individual materials such as concrete, aluminium, stainless steel, graphite and others which will accumulate during this process (a summary of possible activated and contaminated materials and the activity of a single TRIGA fuel element as a function of fuel type and decay time in Bq is presented). The status of the reactor (instrumentation, fuel elements, cooling circuit, ventilation system, re-inspection and maintenance program, cost/benefit) is outlined. (nevyjel)

  18. Operating and test experience of EBR-II

    Sackett, J.I.

    1991-01-01

    EBR-II has operated for 27 years, the longest for any Liquid Metal Reactor (LMR) power plant. During that time, much has been learned about successful LMR operation and design. The basic lesson is that conservatism in design can pay significant dividends in operating reliability. Furthermore, such conservatism need not mean high cost. The EBR-II system emphasizes simplicity, minimizing the number of valves in the heat transport system, for example, and simplifying the primary heat-transport-system layout. Another lesson is that emphasizing reliability of the steam generating system at the sodium-water interface (by using duplex tubes in the case of EBR-II) has been well worth the higher initial costs; no problems with leakage have been encountered in EBR-II's operating history. Locating spent fuel storage in the primary tank and providing for decay heat removal by natural connective flow have also been contributors to EBR-II's success. The ability to accommodate loss of forced cooling or loss of heat sink passively has resulted in benefits for simplification, primarily through less reliance on emergency power and in not requiring the secondary sodium or steam systems to be safety grade. Also, the 'piped-pool' arrangement minimizes thermal stress to the primary tank and enhances natural convective flow. These benefits have been realized through a history of operation that has seen EBR-II evolve through four major phases in its test programs, culminating in its present mission as the Integral Fast Reactor (IFR) prototype. (author)

  19. Operating and test experience of EBR-II

    Sackett, J.I.

    1991-01-01

    EBR-2 has operated for 27 years, the longest for any Liquid Metal Reactor (LMR) power plant. During that time, much has been learned about successful LMR operation and design. The basic lesson is that conversatism in design can pay significant dividends in operating reliability. Furthermore, such conservatism need not mean high cost. The EBR-2 system emphasizes simplicity, minimizing the number of valves in the heat transport system, for example, and simplifying the primary heat-transport-system layout. Another lesson is that emphasizing reliability of the steam generating system at the sodium-water interface (by using duplex tubes in the case of EBR-2) has been well worth the higher initial costs; no problems with leakage have been encountered in EBR-2's operating history. Locating spent fuel storage in the primary tank and providing for decay heat removal by natural connective flow have also been contributors to EBR-2's success. The ability to accommodate loss of forced cooling or loss of heat sink passively has resulted in benefits for simplification, primarily through less reliance on emergency power and in not requiring the secondary sodium or steam systems to be safety grade. Also, the ''piped-pool '' arrangement minimizes thermal stress to the primary tank and enhances natural convective flow. These benefits have been realized through a history of operation that has seen EBR-2 evolve through four major phases in its test programs, culminating in its present mission as the Integral Fast Rector (IFR) prototype. 20 refs., 8 figs., 1 tab

  20. Spatial Operations

    Anda VELICANU

    2010-09-01

    Full Text Available This paper contains a brief description of the most important operations that can be performed on spatial data such as spatial queries, create, update, insert, delete operations, conversions, operations on the map or analysis on grid cells. Each operation has a graphical example and some of them have code examples in Oracle and PostgreSQL.

  1. Operational amplifiers

    Dostal, Jiri

    1993-01-01

    This book provides the reader with the practical knowledge necessary to select and use operational amplifier devices. It presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits.Provides the reader with practical knowledge necessary to select and use operational amplifier devices. Presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits

  2. Operative interventions for failed heller myotomy: a single institution experience.

    Pallati, Pradeep K; Mittal, Sumeet K

    2011-03-01

    Recurrent dysphagia and/or gastroesophageal reflux (GER) are failures of treatment after Heller myotomy for achalasia. We present our single center experience with surgical interventions for these failures. We did a retrospective analysis of a prospectively collected database. Based on preoperative symptoms and endoscopy, esophagogram, and manometry results, patients were divided into three groups to guide management. Telephone follow-up was done using a structured foregut questionnaire. Between December 2003 and June 2009, 16 patients underwent operative interventions for disabling symptoms after previous Heller myotomy. Eight patients presented primarily with recurrent dysphagia and underwent transabdominal Heller myotomy with partial fundoplication. Seven patients reported good to excellent symptom relief at mean follow-up of 42 months. One patient reported no relief and eventually required esophageal bypass with retrosternal gastric pull-up. Four patients presented with uncontrolled GER. Two patients who underwent redo partial fundoplication reported poor symptomatic outcome and one patient has since undergone short limb Roux-en-y gastric bypass (SLRNYGB) with excellent symptom relief. The other two patients underwent SLRNYGB with excellent relief at 10 months. Four patients had end stage achalasia and underwent esophageal resection with reconstruction. All reported excellent symptom relief at mean follow-up of 36 months. Transabdominal redo Heller myotomy for dysphagia has good outcomes. Redo fundoplication for GER after previous myotomy has poor results and SLRNYGB is an effective option in these patients. Esophageal resection remains an effective, albeit morbid, option for end-stage achalasia.

  3. Operating experience with the Harwell thermo-mechanical generators

    Cooke-Yarborough, E.H.

    1980-06-01

    The Stirling-cycle thermo-mechanical generator (TMG) provides small amounts of electrical power continuously over long periods, while requiring much less fuel than other power sources running from hydrocarbon fuel or radio-isotopes. Two of these 25-watt generators, fuelled by propane, have been used to power the UK National Buoy on two successive missions. A total of more than three years experience at sea has now been accumulated. In addition, a 60-watt version has provided the power for a major lighthouse for more than a year. An early development version of the Thermo-mechanical Generator, adapted to run from the heat of a radio-isotope source, was loaded with strontium 90 titanate in October 1974 and has run continuously in the laboratory ever since. The improvements and changes found necessary in the course of 90,000 generator-hours of running time are described, and the improvements in operational performance and reliability which have resulted are outlined. (author)

  4. The safety experience of New Zealand adventure tourism operators.

    Bentley, Tim A; Page, Stephen; Walker, Linda

    2004-01-01

    This survey examined parameters of the New Zealand adventure tourism industry client injury risk. The research also sought to establish priorities for intervention to reduce adventure tourism risk, and identify client injury control measures currently in place (or absent) in the New Zealand adventure tourism industry, with a view to establishing guidelines for the development of effective adventure tourism safety management systems. This 2003 survey builds upon an exploratory study of New Zealand adventure tourism safety conducted by us during 1999. A postal questionnaire was used to survey all identifiable New Zealand adventure tourism operators. The questionnaire asked respondents about their recorded client injury experience, perceptions of client injury risk factors, safety management practices, and barriers to safety. Some 27 adventure tourism activities were represented among the responding sample (n=96). The highest client injury risk was reported in the snow sports, bungee jumping and horse riding sectors, although serious underreporting of minor injuries was evident across the industry. Slips, trips and falls (STF) were the major client injury mechanisms, and a range of risk factors for client injuries were identified. Safety management measures were inconsistently applied across the industry. The industry should consider the implications of poor injury reporting standards and safety management practices generally. Specifically, the industry should consider risk management that focuses on minor (e.g., STF) as well as catastrophic events.

  5. Operational experience with the ALICE High Level Trigger

    Szostak, Artur

    2012-12-01

    The ALICE HLT is a dedicated real-time system for online event reconstruction and triggering. Its main goal is to reduce the raw data volume read from the detectors by an order of magnitude, to fit within the available data acquisition bandwidth. This is accomplished by a combination of data compression and triggering. When HLT is enabled, data is recorded only for events selected by HLT. The combination of both approaches allows for flexible data reduction strategies. Event reconstruction places a high computational load on HLT. Thus, a large dedicated computing cluster is required, comprising 248 machines, all interconnected with InfiniBand. Running a large system like HLT in production mode proves to be a challenge. During the 2010 pp and Pb-Pb data-taking period, many problems were experienced that led to a sub-optimal operational efficiency. Lessons were learned and certain crucial changes were made to the architecture and software in preparation for the 2011 Pb-Pb run, in which HLT had a vital role performing data compression for ALICE's largest detector, the TPC. An overview of the status of the HLT and experience from the 2010/2011 production runs are presented. Emphasis is given to the overall performance, showing an improved efficiency and stability in 2011 compared to 2010, attributed to the significant improvements made to the system. Further opportunities for improvement are identified and discussed.

  6. Operational experience with the ALICE High Level Trigger

    Szostak, Artur

    2012-01-01

    The ALICE HLT is a dedicated real-time system for online event reconstruction and triggering. Its main goal is to reduce the raw data volume read from the detectors by an order of magnitude, to fit within the available data acquisition bandwidth. This is accomplished by a combination of data compression and triggering. When HLT is enabled, data is recorded only for events selected by HLT. The combination of both approaches allows for flexible data reduction strategies. Event reconstruction places a high computational load on HLT. Thus, a large dedicated computing cluster is required, comprising 248 machines, all interconnected with InfiniBand. Running a large system like HLT in production mode proves to be a challenge. During the 2010 pp and Pb-Pb data-taking period, many problems were experienced that led to a sub-optimal operational efficiency. Lessons were learned and certain crucial changes were made to the architecture and software in preparation for the 2011 Pb-Pb run, in which HLT had a vital role performing data compression for ALICE's largest detector, the TPC. An overview of the status of the HLT and experience from the 2010/2011 production runs are presented. Emphasis is given to the overall performance, showing an improved efficiency and stability in 2011 compared to 2010, attributed to the significant improvements made to the system. Further opportunities for improvement are identified and discussed.

  7. The experience of building and operating COMPASS RICH-1

    Birsa, R; Rocco, E; Schiavon, P; Kramer, D; Schroder, W; Dafni, T; Tessarotto, F; Bressan, A; Schill, C; Deschamps, H; Mann, A; Sozzi, F; Colantoni, M; Dibiase, N; Abbon, P; Svec, M; Delagnes, E; Ketzer, B; Joosten, R; Steiger, L; Ciliberti, P; Konigsmann, K; Maggiora, A; Kolosov, V N; Giorgi, M; Sbrizzai, G; Nahle, O; Kunne, F; Sulc, M; Teufel, A; Paul, S; Neyret, D; Rebourgeard, P; Menon, G; Dalla Torre, S; Hagemann, R; Slunecka, M; Martin, A; Magnon, A; Takekawa, S; Finger, M; Bradamante, F; Heinsius, F H; Nerling, F; Gerassimov, S; Polak, J; Alexeev, M; Pizzolotto, C; Chiosso, M; Gobbo, B; Angerer, H; Denisov, O; Ferrero, A; Baum, G; Franco, C; Lehmann, A; Bordalo, P; Duic, V; Konorov, I; Mutter, A; Levorato, S; Robinet, F; von Harrach, D; Fischer, H; Schoenmeier, P; Pesaro, G; Wollny, H; Panzieri, D

    2011-01-01

    COMPASS RICH-1 is a large size gaseous Imaging Cherenkov Detector providing hadron identification in the range from 3 to 55 GeV/c, in the wide acceptance spectrometer of the COMPASS Experiment at CERN SPS. It uses a 3 m long C(4)F(10) radiator, a 21 m(2) large VUV mirror surface and two kinds of photon detectors: MAPMTs and MWPCs with CsI photocathodes, covering a total of 5.5 m(2). It is in operation since 2002 and its performance has increased in time thanks to progressive optimization and mostly to a major upgrade which was implemented in 2006. The main characteristics of COMPASS RICH-1 components are described and some specific aspects related to the radiator gas system, the mirror alignment, the MWPC electrical stability and the readout electronics are discussed. Some key features of the event reconstruction and the PID analysis are presented together with results from the COMPASS RICH-1 performance characterization study. (C) 2010 Elsevier B.V. All rights reserved.

  8. High Temperature Operational Experiences of Helium Experimental Loop

    Kim, Chan Soo; Hong, Sung-Deok; Kim, Eung-Seon; Kim, Min Hwan

    2015-01-01

    The development of high temperature components of VHTR is very important because of its higher operation temperature than that of a common light water reactor and high pressure industrial process. The development of high temperature components requires the large helium loop. Many countries have high temperature helium loops or a plan for its construction. Table 1 shows various international state-of-the-art of high temperature and high pressure gas loops. HELP performance test results show that there is no problem in operation of HELP at the very high temperature experimental condition. These experimental results also provide the basic information for very high temperature operation with bench-scale intermediate heat exchanger prototype in HELP. In the future, various heat exchanger tests will give us the experimental data for GAMMA+ validation about transient T/H behavior of the IHX prototype and the optimization of the working fluid in the intermediate loop

  9. Operational experience from a large EPICS-based accelerator facility

    Ciarlette, D.J.; Gerig, R.

    1995-01-01

    The Advanced Photon Source (APS) at Argonne National Laboratory is a third-generation x-ray light source which uses the Experimental Physics and Industrial Control System (EPICS) to operate its linear accelerator, positron accumulator ring, booster synchrotron, and storage ring equipment. EPICS has been used at the APS since the beginning of installation and commissioning. Currently, EPICS controls approximately 100 VME crates containing over 100,000 process variables. With this complexity, the APS has had to review some of the methods originally employed and make changes as necessary. In addition, due to commissioning and operational needs, higher-level operator software needed to be created. EPICS has been flexible enough to allow this

  10. Performance and operation experience of the Atlas Semiconductor Tracker

    Liang, Zhijun

    2014-01-01

    We report on the operation and performance of the ATLAS Semi-Conductor Tracker (SCT), which has been functioning for 3 years in the high luminosity, high radiation environment of the Large Hadron Collider at CERN. Well also report on the few im- provements of the SCT foreseen for the high energy run of the LHC. We find 99.3% of the SCT modules are operational, the noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to the ideal to allow on-line track reconstruc- tion and invariant mass determination. We will report on the operation and performance of the detector including an overview of the issues encountered. We observe a significant increase in leakage currents from bulk damage due to non-ionizing radiation and make comparisons with the predictions.

  11. Operational Regimes of the National Spherical Torus Experiment; TOPICAL

    D. Mueller; M.G. Bell; R.E. Bell; M. Bitter; T. Bigelow; P. Bonoli; M. Carter; J. Ferron; E. Fredrickson; D. Gates; L. Grisham; J.C. Hosea; D. Johnson; R. Kaita; S.M. Kaye; H. Kugel; B.P. LeBlanc; R. Maingi; R. Majeski; R. Maqueda; J. Menard; M. Ono; F. Paoletti; S. Paul; C.K. Phillips; R. Pinsker; R. Raman; S.A. Sabbagh; C.H. Skinner; V.A. Soukhanovskii; D. Stutman; D. Swain; Y. Takase; J. Wilgen; J.R. Wilson; G.A. Wurden; S. Zweben

    2002-01-01

    The National Spherical Torus Experiment (NSTX) is a proof-of-principle experiment designed to study the physics of Spherical Tori (ST), i.e., low-aspect-ratio toroidal plasmas. Important issues for ST research are whether the high-eta stability and reduced transport theoretically predicted for this configuration can be realized experimentally. In NSTX, the commissioning of a digital real-time plasma control system, the provision of flexible heating systems, and the application of wall conditioning techniques were instrumental in achieving routine operation with good confinement. NSTX has produced plasmas with R/a(approx) 0.85 m/0.68 m, A(approx) 1.25, Ip* 1.1 MA, BT= 0.3-0.45 T, k* 2.2, d* 0.5, with auxiliary heating by up to 4 MW of High Harmonic Fast Waves, and 5 MW of 80 keV D0 Neutral Beam Injection (NBI). The energy confinement time in plasmas heated by NBI has exceeded 100 ms and a toroidal beta (bT= 2m0 and lt;p and gt;/BT02, where BT0 is the central vacuum toroidal magnetic field) up to 22% has be en achieved. HHFW power of 2.3 MW has increased the electron temperature from an initial 0.4 keV to 0.9 keV both with and without producing a significant density rise in the plasma. The early application of both NBI and HHFW heating has slowed the penetration of the inductively produced plasma current, modifying the current profile and, thereby, the observed MHD stability

  12. Operational Regimes of the National Spherical Torus Experiment

    Mueller, D.; Bell, M.G.; Bell, R.E.; Bitter, M.; Bigelow, T.; Bonoli, P.; Carter, M.; Ferron, J.; Fredrickson, E.; Gates, D.; Grisham, L.; Hosea, J.C.; Johnson, D.; Kaita, R.; Kaye, S.M.; Kugel, H.; LeBlanc, B.P.; Maingi, R.; Majeski, R.; Maqueda, R.; Menard, J.; Ono, M.; Paoletti, F.; Paul, S.; Phillips, C.K.; Pinsker, R.; Raman, R.; Sabbagh, S.A.; Skinner, C.H.; Soukhanovskii, V.A; Stutman, D.; Swain, D.; Takase, Y.; Wilgen, J.; Wilson, J.R.; Wurden, G.A.; Zweben, S.

    2002-01-01

    The National Spherical Torus Experiment (NSTX) is a proof-of-principle experiment designed to study the physics of Spherical Tori (ST), i.e., low-aspect-ratio toroidal plasmas. Important issues for ST research are whether the high-eta stability and reduced transport theoretically predicted for this configuration can be realized experimentally. In NSTX, the commissioning of a digital real-time plasma control system, the provision of flexible heating systems, and the application of wall conditioning techniques were instrumental in achieving routine operation with good confinement. NSTX has produced plasmas with R/a ∼ 0.85 m/0.68 m, A ∼ 1.25, Ip * 1.1 MA, BT = 0.3-0.45 T, k * 2.2, d * 0.5, with auxiliary heating by up to 4 MW of High Harmonic Fast Waves, and 5 MW of 80 keV D0 Neutral Beam Injection (NBI). The energy confinement time in plasmas heated by NBI has exceeded 100 ms and a toroidal beta (bT = 2m0 /BT02, where BT0 is the central vacuum toroidal magnetic field) up to 22% has be en achieved. HHFW power of 2.3 MW has increased the electron temperature from an initial 0.4 keV to 0.9 keV both with and without producing a significant density rise in the plasma. The early application of both NBI and HHFW heating has slowed the penetration of the inductively produced plasma current, modifying the current profile and, thereby, the observed MHD stability

  13. Self-assessment as an approach to improvement of efficient implementation of Ukrainian NPP operational experience

    Pecheritsya, L.M.; Lyigots'kij, O.Yi.; Pecheritsya, O.V.; Tarasenko, V.M.

    2012-01-01

    the paper contains a brief description of the procedure for implementation of operational experience, focuses on the role of self -assessment in efficient use of operational experience, presents a review of international and national practices of self-assessment and review of the main features, issues and ways to improve self-assessment of efficient use of operational experience in Ukraine

  14. Operational experiences and upgradation of waste management facilities Trombay, India

    Chander, Mahesh; Bodke, S.B.; Bansal, N.K.

    2001-01-01

    Full text: Waste Management Facilities Trombay provide services for the safe management of radioactive wastes generated from the operation of non power sources at Bhabha Atomic Research Centre, India. The paper describes in detail the current operational experience and facility upgradation by way of revamping of existing processes equipment and systems and augmentation of the facility by way of introducing latest processes and technologies to enhance the safety. Radioactive wastes are generated from the operation of research reactors, fuel fabrication, spent fuel reprocessing, research labs. manufacture of sealed sources and labeled compounds. Use of radiation sources in the field of medical, agriculture and industry also leads to generation of assorted solid waste and spent sealed radiation sources which require proper waste management. Waste Management Facilities Trombay comprise of Effluent Treatment Plant (ETP), Decontamination Centre (DC) and Radioactive Solid Waste Management Site (RSMS). Low level radioactive liquid effluents are received at ETP. Plant has 100 M 3 /day treatment capacity. Decontamination of liquid effluents is effected by chemical treatment method using co- precipitation as a process. Plant has 1800 M 3 of storage capacity. Chemical treatment system comprises of clarifloculator, static mixer and chemical feed tanks. Plant has concentrate management facility where chemical sludge is centrifuged to effect volume reduction of more that 15. Thickened sludge is immobilized in cement matrix. Decontamination Centre caters to the need of equipment decontamination from research reactors. Process used is ultrasonic chemical decontamination. Besides this DC provides services for decontamination of protective wears. Radioactive Solid Waste Management Site is responsible for the safe management of solid waste generated at various research reactors, plants, laboratories in Bhabha Atomic Research Centre. Spent sealed radiation sources are also stored

  15. Operation experiences of JOYO fuel failure detection system

    Tamura, Seiji; Hikichi, Takayoshi; Rindo, Hiroshi.

    1982-01-01

    Monitoring of fuel failure in the experimental fast reactor JOYO is provided by two different methods, which are cover gas monitoring (FFDCGM) by means of a precipitator, and delayed neutron monitoring (FFDDNM) by means of neutron detectors. The interpretation of signals which were obtained during the reactor operation for performance testings, was performed. The countrate of the CGM is approximately 120 cps at 75MW operation, whose sources are due to Ne 23 , Ar 41 , and Na 24 . And the countrate of the DNM is approximately 2300 cps at 75MW operation which is mainly due to leakage neutron from the core. With those background of the systems, alarm level for monitoring was set at several times of each background level. The reactor has been operated for 5 years, the burn-up of the fuel is 40,000 MWD/T at the most. No trace of any fuel failure has been observed. The fact is also proven by the results of cover gas and sodium sampling analysis. In order to evaluate sensitivity of the FFD systems, a preliminary simulation study has been performed. According to the results, a signal level against one pin failure of 0.5 mm 2 hole may exceed the alarm level of the FFDCGM system. (author)

  16. Operational Experience and Performance with the ATLAS Pixel detector

    Yang, Hongtao; The ATLAS collaboration

    2018-01-01

    In this presentation, I will discuss the operation of ATLAS Pixel Detector during Run 2 proton-proton data-taking at √s=13 TeV in 2017. The topics to be covered include 1) the bandwidth issue and how it is mitigated through readout upgrade and threshold adjustment; 2) the auto-corrective actions; 3) monitoring of radiation effects.

  17. Use of simulators in operative dental education: experience in ...

    Abstract: Background: Though the use of simulators in operative dentistry is not new, the teaching and learning practices that take place during clinical sessions in skills laboratories are rarely reported. This study was designed to determine the current prac- tices relating to teaching and learning of dental clinical skills in ...

  18. Operational experience with the BNL magnetron H- source

    Witkover, R.L.

    1983-01-01

    A magnetron H - source with a grooved cathode has been in operation at the BNL Linac for over 18 months. The source has run at 5 pps with a 600 μsec pulse width for periods as long as 5 months. Its development and performance will be discussed

  19. Federated software defined network operations for LHC experiments

    Kim, Dongkyun; Byeon, Okhwan; Cho, Kihyeon

    2013-09-01

    The most well-known high-energy physics collaboration, the Large Hadron Collider (LHC), which is based on e-Science, has been facing several challenges presented by its extraordinary instruments in terms of the generation, distribution, and analysis of large amounts of scientific data. Currently, data distribution issues are being resolved by adopting an advanced Internet technology called software defined networking (SDN). Stability of the SDN operations and management is demanded to keep the federated LHC data distribution networks reliable. Therefore, in this paper, an SDN operation architecture based on the distributed virtual network operations center (DvNOC) is proposed to enable LHC researchers to assume full control of their own global end-to-end data dissemination. This may achieve an enhanced data delivery performance based on data traffic offloading with delay variation. The evaluation results indicate that the overall end-to-end data delivery performance can be improved over multi-domain SDN environments based on the proposed federated SDN/DvNOC operation framework.

  20. Performance and Operation Experience of the ATLAS Semiconductor Tracker

    Gallop, B J; The ATLAS collaboration

    2013-01-01

    We report on the operation and performance of the ATLAS Semi-Conductor Tracker (SCT), which has been functioning for 3 years in a high luminosity, high radiation environment. The SCT is constructed of 4088 silicon detector modules, for a total of 6.3 million strips. Each module operates as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel, made of 4 cylinders, and two end-cap systems made of 9 disks. The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibres. We find 99.3% of the SCT modules are operational, the noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to the ideal to allow on-line track reconstruction and invariant mass determination. We will report on the operation an...

  1. Performance and Operation Experience of the ATLAS Semiconductor Tracker

    Gallop, B J

    2014-01-01

    We report on the operation and performance of the ATLAS Semi-Conductor Tracker (SCT), which has been functioning for 3 years in a high luminosity, high radiation environment. The SCT is constructed of 4088 silicon detector modules, for a total of 6.3 million strips. Each module operates as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel, made of 4 cylinders, and two end-cap systems made of 9 disks. The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibres. We find $99.3\\%$ of the SCT modules are operational, the noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to the ideal to allow on-line track reconstruction and invariant mass determination. We will report on the operation...

  2. Intra-operative parathyroid hormone measurements – experience of ...

    Background. Surgery is the treatment of choice for symptomatic primary hyperparathyroidism. The majority of research concerning intra-operative parathyroid hormone (ioPTH) measurements is conducted in university hospitals. Whether ioPTH measurements are feasible and useful in predicting the presence of remaining ...

  3. French experience in operating pressurized water reactor power stations. Ten years' operation of the Ardennes power station

    Teste du Bailler, A.; Vedrinne, J.F.

    1978-01-01

    In the paper the experience gained over ten years' operation of the Ardennes (Chooz) nuclear power station is summarized from the point of view of monitoring and control equipment. The reactor was the first pressurized water reactor to be installed in France; it is operated jointly by France and Belgium. The equipment, which in many cases consists of prototypes, was developed for industrial use and with the experience that has now been gained it is possible to evaluate its qualities and defects, the constraints which it imposes and the action that has to be taken in the future. (author)

  4. Summary of operating experience in Swiss nuclear power plants 1994

    1995-05-01

    In 1994 the Swiss nuclear power plants produced their highest-ever combined annual output. Their contribution to total electricity generation in the country was 36%. At Muehleberg the power uprate, undertaken in 1993, was effective for the first time for an entire year. The larger capacity of the new steam generators installed in 1993 in unit 1 of the Beznau NPP allows for an electric output of 103% of nominal power. The plant efficiency of the Goesgen and Leibstadt units was increased by replacing the low pressure turbines by the new ones with a modern design. The application for a power uprate of the Leibstadt reactor is still pending. For the first time in Switzerland, one of the reactor units, Beznau 2, operated on an extended cycle of one and a half years, with no refuelling outage in 1994. In spite of the replacements of two of its three low pressure turbines, Goesgen had the shortest refuelling shutdown since the start of commercial operation. The average number of reactor scrams at the Swiss plants remained stable, at less than one scram per reactor year. Re-inspection of crack indications detected in 1990 in the core shroud of the Muehleberg reactor revealed no significant changes. A crack indication was found in one of the other welds inspected. The Swiss government issued a limited operating licence for Beznau 2 for the next ten years, i.e. until the end of 2004. The only other unit with a limited operating licence (until 2003) is Muehleberg. The remaining three reactor units, have no time limits on their operating licences, in accordance with the Atomic Law. Goesgen is the first Swiss nuclear power plant having now produced more than 100 billion kWh. As from January 1, 1995, the nominal net power of the largest Swiss reactor unit, Leibstadt, has been fixed at 1030 MW; that of the Goesgen NPP has been increased by 25 MW to 965 MW. (author) figs., tabs

  5. Summary of operating experience in Swiss nuclear power plants 1994

    NONE

    1995-05-01

    In 1994 the Swiss nuclear power plants produced their highest-ever combined annual output. Their contribution to total electricity generation in the country was 36%. At Muehleberg the power uprate, undertaken in 1993, was effective for the first time for an entire year. The larger capacity of the new steam generators installed in 1993 in unit 1 of the Beznau NPP allows for an electric output of 103% of nominal power. The plant efficiency of the Goesgen and Leibstadt units was increased by replacing the low pressure turbines by the new ones with a modern design. The application for a power uprate of the Leibstadt reactor is still pending. For the first time in Switzerland, one of the reactor units, Beznau 2, operated on an extended cycle of one and a half years, with no refuelling outage in 1994. In spite of the replacements of two of its three low pressure turbines, Goesgen had the shortest refuelling shutdown since the start of commercial operation. The average number of reactor scrams at the Swiss plants remained stable, at less than one scram per reactor year. Re-inspection of crack indications detected in 1990 in the core shroud of the Muehleberg reactor revealed no significant changes. A crack indication was found in one of the other welds inspected. The Swiss government issued a limited operating licence for Beznau 2 for the next ten years, i.e. until the end of 2004. The only other unit with a limited operating licence (until 2003) is Muehleberg. The remaining three reactor units, have no time limits on their operating licences, in accordance with the Atomic Law. Goesgen is the first Swiss nuclear power plant having now produced more than 100 billion kWh. As from January 1, 1995, the nominal net power of the largest Swiss reactor unit, Leibstadt, has been fixed at 1030 MW; that of the Goesgen NPP has been increased by 25 MW to 965 MW. (author) figs., tabs.

  6. Dhruva: Main design features, operational experience and utilization

    Agarwal, S.K. [Reactor Group, BARC, Trombay, Mumbai 400085 (India)]. E-mail: swarajagarwal2000@yahoo.com; Karhadkar, C.G. [Reactor Group, BARC, Trombay, Mumbai 400085 (India); Zope, A.K. [Reactor Group, BARC, Trombay, Mumbai 400085 (India); Singh, Kanchhi [Reactor Group, BARC, Trombay, Mumbai 400085 (India)

    2006-04-15

    Dhruva is a product of technological initiatives taken during mid seventies when a need was felt for another research reactor having a high neutron flux to meet the growing demands of research and development in the frontier areas of science and engineering. In addition production of radioisotopes of high specific activity and the diverse requirements of a broad based user community had to be synthesized into a viable system, which could be engineered within the limited means available in the country. This high neutron flux reactor was designed, constructed and commissioned entirely by Indian scientists and engineers and it reflects the country's resolve to achieve self-reliance in the nuclear reactor technology. Dhruva is a 100 MW (thermal) research reactor with metallic natural uranium as fuel, heavy water as moderator, coolant and reflector, giving a maximum thermal neutron flux of 1.8 x 10{sup 14} n/cm{sup 2}/s. Since its first criticality on 8th August 1985, a number of experimental facilities have been added which have proven to be highly attractive for universities and industrial researchers for their scientific merits in various fields. One of the major utilization areas has been the neutron beam research using several neutron spectrometers, all of which were built in-house. A guide tube facility comprising of two neutron guides and another experimental set-up with a multi-instrument beam line have enabled further enhancement of the utilization of this National Facility by the academic institutions in the country. Production of radioisotopes of high specific activity and in increased quantity has fulfilled growing demands for many applications. The write-up provides an overview of the reactor covering its design; layout, safety features, utilization and operating experience along with description of some of the specific experimental facilities.

  7. Operating experience review -- Conduct of operations at Department of Energy facilities

    1994-08-01

    This research examined human error related occurrences, reported in the ORPS database, for the purpose of identifying weaknesses in the implementation of the guidance regarding the Conduct of Operations contained in DOE 5480.19. Specifically, this research examined three separate samples of occurrence reports from Defense Program facilities, which cited human error as a direct or contributing cause. These reports were evaluated using a coding scheme which incorporated the guidelines present in 5480.19, as well as a number of generic human factors concerns. The second chapter of this report summarizes the coding scheme which was used to evaluate the occurrence reports. Since the coding scheme is quite lengthy, only the parts of the scheme needed to make the remainder of the report clear are included in this chapter. Details on the development and content of the coding scheme are reported in Appendices A, B, and C. Chapter 3 presents the analysis of three different data sets. This chapter demonstrates that similar results were obtained across different data sets, collected at different points in time, and coded by different raters. The implications of the results obtained in Chapter 3 are discussed in Chapter 4. This chapter makes a number of suggestions for reducing the problems found in the occurrence reports. Chapter 5 applies the methodology that has been developed in this report to two facilities at Los Alamos National Laboratory. Finally, Chapter 6 reiterates the major findings of this report. Several additional analyses appear in appendices at the end of this report

  8. Liquid metal cooled reactors: Experience in design and operation

    2007-12-01

    on key fast reactor technology aspects in an integrative sense useful to engineers, scientists, managers, university students and professors. This publication has been prepared to contribute toward the IAEA activity to preserve the knowledge gained in the liquid metal cooled fast reactor (LMFR) technology development. This technology development and experience include aspects addressing not only experimental and demonstration reactors, but also all activities from reactor construction to decommissioning. This publication provides a survey of worldwide experience gained over the past five decades in LMFR development, design, operation and decommissioning, which has been accumulated through the IAEA programmes carried out within the framework of the TWG-FR and the Agency's INIS and NKMS

  9. Experiments on the Impact of language Problems in the Multi-cultural Operation of NPPs' Emergency Operation

    Kang, Seongkeun; Kim, Taehoon; Seong, Poong Hyun; Ha, Jun Su

    2016-01-01

    In 2010, The Korea Electric Power Corporation (KEPCO) was awarded a multi-billion dollar bid to construct the first nuclear power plant in Barakah, UAE. One must keep in mind however, that with technology transfer and international cooperation comes a host of potential problems arising from cultural differences such as language, everyday habitudes and workplace expectation. As of now, how problematic these potential issues may become is unknown. Of the aforementioned factors, communication is perhaps of foremost importance. We investigated UAE culture-related issues through analysis of operating experience reviews (OERs) and came to the conclusion that the language barrier needed utmost attention. Korean nuclear power plant operators will work in UAE and will operate the NPPs with operators and managers of other nationalities as well. The purpose of this paper is firstly to confirm that operators are put under mental stress, and secondly to demonstrate the decline in accuracy when they must work in English. Reducing human error is quite important to make nuclear power plants safer. As the mental workload of human operator is increased, the probability of a human error occurring also increases. It will have a negative influence on the plant’s safety. There are many factors which can potentially increase mental workload. We focused on communication problem which is a key factor of increasing mental workload because many Korean operators will work in UAE nuclear power plants and may work together with UAE operators. From these experiments we compared how performance of both Korean and UAE subjects were decreased when they use English. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To

  10. Experiments on the Impact of language Problems in the Multi-cultural Operation of NPPs' Emergency Operation

    Kang, Seongkeun; Kim, Taehoon; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of); Ha, Jun Su [KUSTAR, Abu Dhabi (United Arab Emirates)

    2016-10-15

    In 2010, The Korea Electric Power Corporation (KEPCO) was awarded a multi-billion dollar bid to construct the first nuclear power plant in Barakah, UAE. One must keep in mind however, that with technology transfer and international cooperation comes a host of potential problems arising from cultural differences such as language, everyday habitudes and workplace expectation. As of now, how problematic these potential issues may become is unknown. Of the aforementioned factors, communication is perhaps of foremost importance. We investigated UAE culture-related issues through analysis of operating experience reviews (OERs) and came to the conclusion that the language barrier needed utmost attention. Korean nuclear power plant operators will work in UAE and will operate the NPPs with operators and managers of other nationalities as well. The purpose of this paper is firstly to confirm that operators are put under mental stress, and secondly to demonstrate the decline in accuracy when they must work in English. Reducing human error is quite important to make nuclear power plants safer. As the mental workload of human operator is increased, the probability of a human error occurring also increases. It will have a negative influence on the plant’s safety. There are many factors which can potentially increase mental workload. We focused on communication problem which is a key factor of increasing mental workload because many Korean operators will work in UAE nuclear power plants and may work together with UAE operators. From these experiments we compared how performance of both Korean and UAE subjects were decreased when they use English. We designed experimental methods to be able to check this problem qualitatively and quantitatively. We analyzed four factors to find the communication problems from the experiments which are accuracy, efficiency, NASA-TLX, and brain wave. Accuracy, efficiency, brain wave are quantitative factors, and NASA-TLX is qualitative factor. To

  11. Experiments on data presentation to process operators in diagnostic tasks

    Rasmussen, Jens; Goodstein, L. P.

    1972-01-01

    Safety and reliability considerations in modern power plants have prompted our interest in man as an information receiver - especially in diagnostic tasks where the growing complexity of process plants and hence the amount of data involved make it imperative to give the staff proper support....... The great flexibility and capacity of the process computer for data reduction and presentation and for storing information on plant structure and functions give the system designer great freedom in the layout of information display for the staff, but the problem for the designer is how to make proper use...... of this freedom to support the operators efficiently. This is especially important in connection with unique, high-risk, and generally improbable abnormalities in plant functioning. Operator tasks and mental models and the need for matching the encoded information about the plant to these models are treated...

  12. Safety related experience in FFTF startup and operation

    Peterson, R.E.; Halverson, T.G.; Daughtry, J.W.

    1982-06-01

    The Fast Flux Test Facility (FFTF) is a 400 MW(t) sodium cooled fast reactor operating at the Hanford Engineering Development Laboratory, Richland, Washington, to conduct fuels and materials testing in support of the US LMFBR program. Startup and initial power ascension testing of the facility involved a comprehensive series of readiness reviews and acceptance tests, many of which relate to the inherent safety of the plant. Included are physics measurements, natural circulation, integrated containment leakage, shielding effectiveness, fuel failure detection, and plant protection system tests. Described are the measurements taken to confirm the design safety margins upon which the operating authorization of the plant was based. These measurements demonstrate that large margins of safety are available in the FFTF design

  13. Hydraulic screw fastening devices - design, maintenance, operational experience

    Lachner.

    1976-01-01

    With hydraulic screw fastening devices, pretension values with a maximum deviation of +-2.5% from the rated value can be achieved. This high degree of pretension accuracy is of considerable importance with regard to the safety factor required for the screw connection between reactor vessel head and reactor vessel. The operating rhythm of a nuclear power station with its refuelling art regular intervals makes further demands on the screw fastening device, in particular in connection with the transport of screws and for nuts. The necessary installations extend the screw fastening device into a combination of a high-pressure hydraulic cylinder system with an electrical or pneumoelectrical driving unit and an electrical control unit. Maintenance work is complicated by the large number of identical, highly stressed structural elements in connection with an unfavourable relation operating time/outage time. The problems have been perpetually reduced by close cooperation between the manufacturers and users of screw fastening devices. (orig./AK) [de

  14. Licensing Support Experience of the BN-600 Operation

    Khrennikov, N.; Sintsov, A.

    2013-01-01

    License procedure - Main principle: • All works, including fatigue tests of new types of fuel, are carried out at the unit 3 Beloyarsk nuclear power plants with the BN-600 reactor with the justification of the regulatory body. • Justification procedure is standard for all power units and independent from the reactor types. • The regulatory body and independent experts or technical support organizations, which can be involved in this work by the regulatory body, review SAR, operational manuals and other operator documents. • Safety requirements (i.e. Federal rules and codes). The project and design documents shall meet safety requirements. • The technical and organizational measures for safety guarantee shall meet well-known results of the research investigations or shall be experimental validate

  15. Operating experience of a portable thermophotovoltaic power supply

    Becker, Frederick E.; Doyle, Edward F.; Shukla, Kailash

    1999-03-01

    Two configurations of man-portable thermophotovoltaic (TPV) power supplies based on Thermo Power's supported continuous fiber emitter have been designed, built, and are being tested. The systems use narrow-band, fibrous, ytterbia emitters radiating to bandgap matched silicon photovoltaic arrays with dielectric stack filters for optical energy recovery and recuperators for thermal energy recovery. The systems have been designed for operation with propane and with combustion air preheat temperatures of up to 1250 K. To operate at air preheat temperatures above the auto-ignition temperature of the fuel, a unique fuel delivery system was devised which results in the micromixing and rapid combustion of the fuel and air right in the emitter fibers. This allows the ytterbia emitter fibers to run much hotter (˜2000 K) than any of the surrounding structure.

  16. Entering 'A NEW REALM' of KIBO Payload Operations - Continuous efforts for microgravity experiment environment and lessons learned from real time experiment operations in KIBO -

    Sakagami, K; Goto, M; Matsumoto, S; Ohkuma, H

    2011-01-01

    On January 22nd, 2011(JST), KOUNOTORI2 (H-II Transfer Vehicle: HTV2) was successfully launched from Tanegashima Space Center toward the International Space Station (ISS) and two new JAXA payload racks, Kobairo rack and MSPR (Multi-purpose Small Payload Rack) were transferred to ISS/KIBO (Japanese Experiment Module: JEM). In addition to Saibo rack and Ryutai rack which are already in operation in KIBO, in total 4 Japanese experiment payload racks start operations in KIBO. Then KIBO payload operations embark on a new realm, full utilization phase. While the number and variety of microgravity experiments become increasing, simultaneous operation constraints should be considered to achieve multitask payload operations in ISS/KIBO and ever more complicated cooperative operations between crewmember and flight control team/science team are required. Especially for g-jitter improvement in ISS/KIBO, we have greatly advanced cooperative operations with crewmember in the recent increment based on the microgravity data analysis results. In this paper, newly operating Japanese experiment payloads characteristics and some methods to improve g-jitter environment are introduced from the front line of KIBO payload operations.

  17. Operating experience with the polarized electron gun at SLAC

    Alguard, M.J.; Baum, G.; Clendenin, J.E.; Hughes, V.W.; Lubell, M.S.; Miller, R.H.; Raith, W.; Schuler, K.P.; Sodja, J.

    1977-03-01

    During the two years of operation of the SLAC Polarized Electron Gun (PEGGY), the electron intensity delivered to the target has increased from 7 x 10 7 e - /pulse to 1 x 10 9 e - /pulse. The polarization is 0.85 with no measurable degradation caused by acceleration through the linear accelerator. The predominant cause of downtime is replenishment of lithium, which now averages 43 hours. The lifetime of a lithium load is about 175 hours

  18. Operational Experience from Swedish nuclear power plants 1996

    1997-01-01

    A summary of two pages is given for each Swedish reactor with data on availability, scrams, radiation doses and important events during 1996. Special reports are presented on the following issues: Reactor core spray system inoperable at OKG-2, Containment pressure relief system incorrectly closed at Forsmark-1, Isolation condenser blocked for residual heat and continued operation with defective isolation valve at OKG-1; and Degraded pressure suppression function of the containment at Barsebaeck-2

  19. Membrane Bioreactors design and operation improvements: The Spanish Experience

    Iglesias Esteban, R.; Ortega de Miguel, E.; Martinez Tarifa, M. A.; Simon Andreu, P.; Moragas Bouyart, L.; Garcia Fernandez, E.; Robuste Cartro, J.; Rodriguez-Roda layret, I.

    2012-01-01

    A Membrane Bioreactor (MBR) is a modification of a conventional activated sludge (CAS) plant where the secondary settling ins replaced by a low pressure ultrafiltration (UF) or micro filtration (MF) membranes separation process in order to obtain an effluent almost free of suspended solids and microorganisms. since the first MBR installation in 2002, the number and capacity of these systems have exponentially increased in spain, driven by the high quality of the effluent which allows direct reuse and discharge into environmentally sensitive areas, the compactness and automation of these plants and the possibility of upgrading existing wastewater treatment plants (WWTP) which no longer reach the required effluent quality levels. There were 45 operating MBR systems in 2011 and the total municipal wastewater treatment capacity by this type of plants will be about 90 hm 3 in 204 when the current projects have been implemented. Today, Spain public and private wastewater management agencies consider MBR plants as an alternative of treatment but first they had to face a complex learning period to operate and design this kind of system. A significant progress has been made over the last years, but especially energy efficiency responds to the challenge of continuous improvement. Membrane fouling control consumes most of the energy involved in the process therefore, anti fouling materials and better membrane air-scour systems that allow the frequency and intensity of air flow to be controlled in realtime, are being investigated. This brings MBR closer to the CAS process in terms of energy efficiency. Breakthroughs in the design and operation of MBR plants are being collected in a guide for the implementation of MBR led by CEDEX, in which the main managers and operators are involved. This paper presents some of these improvements. (Author) 9 refs.

  20. Operating experience with the IMPELA-10/50 industrial linac

    Ungrin, J.; Alexander, S.B.; Craig, S.T.; Frketich, G.; Mason, V.A.; McIntyre, I.L.; Simpson, M.P.; Smyth, D.L.; West, R.J.; White, B.F.

    1991-01-01

    AECL is building and marketing the IMPELA family of high-power linear electron accelerators designed specifically for the industrial market. The accelerators are built around an L-band on-axis coupled structure that is assembled in a modular fashion and is driven in the long-pulse mode with a modulating anode klystron. A wide range of average power is achieved with the same basic accelerator components by simply changing the beam duty factor and the size of the power supply. The control system for the IMPELA family is built around a simplified operator interface that incorporates automatic sequences, fast control loops, self-diagnostics and the instrumentation that is key to reliable, simple operation and rapid maintenance. The first member of the IMPELA family, the 10 MeV, 50 kW, IMPELA-10/50, is a highly instrumented industrial prototype that has been operating at fun power since 1989 November. It is now undergoing prolonged testing at Chalk River Laboratories

  1. Operation experience with the CYCLONE-OCTOPUS combination

    Bol, J.-L.; Chevalier, A.; Jongen, Y.; Lacroix, M.; Mathy, F.; Ryckewaert, G.

    1987-01-01

    Over the last year (till September 1986) the CYCLONE-OCTOPUS combination has been operated almost 85 % of the total possible time for nuclear physics, isotope production, radiobiology and neutrontherapy and technological applications. A new ECR-source for multicharged heavy ions using a Sm-Co permanent magnet octupole (OCTOPUS) was constructed at the C.R.C. in Louvain-la- Neuve during 1985. The source was put into full operation with the cyclotron by the end of October 1985. A minor problem of short term instability of the beam intensity was solved by changing the main stage microwave feed from radial to axial. During restart after this modification, a hole was melted, by accident due to a human error, in the octupole envelope, causing a water leak. Except from this, the new source operated continuously and reliably up to now. The performance level, which is comparable now to that of ECREVIS, is still preliminary and should be improved by future development. (author)

  2. Performance and operation experience of the Atlas Semiconductor Tracker

    Liang, Z; The ATLAS collaboration

    2013-01-01

    We report on the operation and performance of the ATLAS Semi-Conductor Tracker (SCT), which has been functioning for 3 years in the high luminosity, high radiation environment of the Large Hadron Collider at CERN. We’ll also report on the few improvements of the SCT foreseen for the high energy run of the LHC. The SCT is constructed of 4088 silicon detector modules, for a total of 6.3 million strips. Each module operates as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel, made of 4 cylinders, and two end-cap systems made of 9 disks. The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibres. We find 99.3% of the SCT modules are operational, the noise occupancy and hit efficiency exceed the design specifications; the alig...

  3. Operational experience of the Marcoule reactors; Experience d'exploitation des reacteurs de Marcoule

    Conte, F [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1963-07-01

    The results obtaining from three years operation of the reactors G-2, G-3 have made it possible to accumulate a considerable amount of operational experience of these reactors. The main original points: - the pre-stressed concrete casing - the possibility of loading while under power - automatic temperature control have been perfectly justified by the results of operation. The author confirms the importance of these original solutions and draws conclusions concerning the study of future nuclear power stations. (author) [French] Les resultats atteints apres trois ans de fonctionnement des reacteurs G-2/G-3 permettent une accumulation considerable de l'experience d'exploitation de ces reacteurs. Les principales originalites: - caisson en beton precontraint - chargement en marche - surveillance automatique des temperatures sont largement justifiees par l'exploitation actuelle. L'auteur confirme l'interet de ces solutions d'avant-garde et en tire des conclusions pour les etudes de futures centrales nucleaires. (auteur)

  4. 0 + 5 Vascular Surgery Residents' Operative Experience in General Surgery: An Analysis of Operative Logs from 12 Integrated Programs.

    Smith, Brigitte K; Kang, P Chulhi; McAninch, Chris; Leverson, Glen; Sullivan, Sarah; Mitchell, Erica L

    2016-01-01

    Integrated (0 + 5) vascular surgery (VS) residency programs must include 24 months of training in core general surgery. The Accreditation Council for Graduate Medical Education currently does not require specific case numbers in general surgery for 0 + 5 trainees; however, program directors have structured this time to optimize operative experience. The aim of this study is to determine the case volume and type of cases that VS residents are exposed to during their core surgery training. Accreditation council for graduate medical education operative logs for current 0 + 5 VS residents were obtained and retrospectively reviewed to determine general surgery case volume and distribution between open and laparoscopic cases performed. Standard statistical methods were applied. A total of 12 integrated VS residency programs provided operative case logs for current residents. A total of 41 integrated VS residents in clinical years 2 through 5. During the postgraduate year-1 training year, residents participated in significantly more open than laparoscopic general surgery cases (p surgery cases are hernia repair (20%), skin and soft tissue (7.4%), and breast (6.3%). Residents in programs with core surgery over 3 years participated in significantly more general surgery operations compared with residents in programs with core surgery spread out over 4 years (p = 0.035). 0 + 5 VS residents perform significantly more open operations than laparoscopic operations during their core surgery training. The majority of these operations are minor, nonabdominal procedures. The 0 + 5 VS residency program general surgery operative training requirements should be reevaluated and case minimums defined. The general surgery training component of 0 + 5 VS residencies may need to be restructured to meet the needs of current and future trainees. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  5. Shippingport Atomic Power Station Operating Experience, Developments and Future Plans

    Feinroth, H.; Oldham, G.M.; Stiefel, J.T.

    1963-01-01

    This paper describes and evaluates five years of operation and test of the Shippingport Atomic Power Station and discusses the current technical developments and future plans of the Shippingport programme. This programme is directed towards development of the basic technology of light-water reactors to provide the basis for potential reduction in the costs of nuclear power. The Shippingport reactor plant has operated for over five years and has been found to integrate readily into a utility system either as a base load or peak load unit. Plant component performance has been reliable. There have been no problems in contamination or waste disposal. Access to primary coolant components for maintenance has been good, demonstrating the integrity of fuel elements. Each of the three refuelling operations performed since start-up of Shippingport has required successively less time to accomplish. Recently, the third seed was refuelled in 32 working days, about one quarter the time required for the first refuelling. The formal requirements of personnel training, written administrative procedures, power plant manuals, etc., which have been a vital factor in the successful implementation of the Shippingport programme, are described. The results obtained from the comprehensive test programme carried out at Shippingport are compared with calculations, and good agreement has been obtained. Reactor core performance, plant stability, and response to load changes, fuel element and control rod performance, long-term effects such as corrosion and radiation level build-up, component performance, etc., are discussed in this paper. The principal objective of the current and future programmes of the Shippingport Project in advancing the basic technology of water-cooled reactors is discussed. This programme includes the continued operation of the Shippingport plant, and the development, design, manufacture and test operation of a long-life, highpower density second core - Core 2. At its

  6. Experience gained in enhancing operational safety at ComEd`s nuclear power plants

    Elias, D [Commonwealth Edison Co. (United States)

    1997-09-01

    The following aspects of experience gained in enhancing operational safety at Comed`s nuclear power plants are discussed: nuclear safety policy; centralization/decentralization; typical nuclear operating organization; safety review boards; human performance enhancement; elements of effective nuclear oversight.

  7. Experience gained in enhancing operational safety at ComEd's nuclear power plants

    Elias, D.

    1997-01-01

    The following aspects of experience gained in enhancing operational safety at Comed's nuclear power plants are discussed: nuclear safety policy; centralization/decentralization; typical nuclear operating organization; safety review boards; human performance enhancement; elements of effective nuclear oversight

  8. Operating systems

    Tsichritzis, Dionysios C; Rheinboldt, Werner

    1974-01-01

    Operating Systems deals with the fundamental concepts and principles that govern the behavior of operating systems. Many issues regarding the structure of operating systems, including the problems of managing processes, processors, and memory, are examined. Various aspects of operating systems are also discussed, from input-output and files to security, protection, reliability, design methods, performance evaluation, and implementation methods.Comprised of 10 chapters, this volume begins with an overview of what constitutes an operating system, followed by a discussion on the definition and pr

  9. Operational calculus

    Boehme, Thomas K

    1987-01-01

    Operational Calculus, Volume II is a methodical presentation of operational calculus. An outline of the general theory of linear differential equations with constant coefficients is presented. Integral operational calculus and advanced topics in operational calculus, including locally integrable functions and convergence in the space of operators, are also discussed. Formulas and tables are included.Comprised of four sections, this volume begins with a discussion on the general theory of linear differential equations with constant coefficients, focusing on such topics as homogeneous and non-ho

  10. Operating experiences with Neutron Overpower Trip Systems in Ontario Hydro's CANDU nuclear plants

    Hnik, J.; Kozak, J.

    1991-01-01

    Operating experiences with Neutron Over Power Trip (NOP) Systems in different Ontario Hydro CANDU nuclear power plants are discussed. Lessons learned from the system operation and their impact on design improvements are presented. Retrofitting of additional tools, such as Shutdown System Monitoring computers, to improve operator interaction with the system is described. Experiences with the reliability of some of the NOP system components is also discussed. Options for future enhancements of system performance and operability are identified. (author)

  11. Strengthening the control on radioactive sources - Cernavoda NPP operating experience

    Daian, I.; Simionov, V.

    2005-01-01

    This paper presents the national legal frame governing the radioactive source management, legislative requirements introduced during last years and current status of controlled radioactive sources program at Cernavoda NPP. Romania has only one nuclear power plant, Cernavoda NPP, equipped with five PHWR - CANDU-6 Canadian type reactors - with a 700 MW(e) gross capacity each, in different implementation stages. The legal representative of the nuclear power production sector in Romania is 'Nuclearelectrica' S.A. National Company (SNN). SNN is a governmental company controlled by the Ministry of Industry and Trade. The company has headquarters in Bucharest and three subsidiaries: - CNE-PROD Cernavoda (CNE-PROD), operating the Cernavoda NPP - Unit 1; - CNE-INVEST Cernavoda, in charge with the completion of Unit 2 and with the preservation of Units 3,4,5; - Nuclear Fuel Plant in Pitesti (FCN). Unit 1 is in commercial operation since December 2, 1996, Unit 2 is under construction (80% completed) and Units 3, 4, 5 are under preservation. The operation of Cernavoda NPP implies use of radioactive sources that may present a significant risk to health, property and the environment when control is lost. Within the last years CNCAN issued new regulations stating clear responsibilities for the different institutions involved in radioactive materials control programs. To manage radioactive sources in a safe way CNE-PROD established and revised the Controlled Radioactive Sources Program, as part of Station Radiation Protection Regulation, ensuring strict recording of the radioactive sources and their usage, ensuring physical and radiological security, protecting the personnel, members of the public and the environment from the hazards of ionizing radiation during the life cycle of the plant, including decommissioning. (authors)

  12. Strengthening the control on radioactive sources - Cernavoda NPP operating experience

    Daian, I.; Simionov, V.

    2005-01-01

    Full text: This paper presents the national legal frame governing the radioactive source management, legislative requirements introduced during last years and current status of controlled radioactive sources program at Cernavoda NPP. Romania has only one nuclear power plant, Cernavoda NPP, equipped with five PHWR - CANDU-6 Canadian type reactors - with a 700 MW(e) gross capacity each, in different implementation stages. The legal representative of the nuclear power production sector in Romania is 'Nuclearelectrica' S.A. National Company (SNN). SNN is a governmental company controlled by the Ministry of Industry and Trade. The company has headquarters in Bucharest and three subsidiaries: - CNE-PROD Cernavoda (CNE-PROD), operating the Cernavoda NPP - Unit 1; - CNE-INVEST Cernavoda, in charge with the completion of Unit 2 and with the preservation of Units 3,4,5; - Nuclear Fuel Plant in Pitesti (FCN). Unit 1 is in commercial operation since December 2, 1996, Unit 2 is under construction (80% completed) and Units 3, 4, 5 are under preservation. The operation of Cernavoda NPP implies use of radioactive sources that may present a significant risk to health, property and the environment when control is lost. Within the last years CNCAN issued new regulations stating clear responsibilities for the different institutions involved in radioactive materials control programs. To manage radioactive sources in a safe way CNE-PROD established and revised the Controlled Radioactive Sources Program, as part of Station Radiation Protection Regulation, ensuring strict recording of the radioactive sources and their usage, ensuring physical and radiological security, protecting the personnel, members of the public and the environment from the hazards of ionizing radiation during the life cycle of the plant. (authors)

  13. Summary of Operating Experience in Swiss Nuclear Power Plants 1999

    NONE

    2000-05-15

    The five Swiss nuclear power units produced a net total of 23.6 TWh of electricity in 1999 - not as high as the all-time record (24.45 TWh in 1998), but nonetheless a solid operational performance. The nuclear share in overall electricity production was 35.3%, again lower than the previous year's 40%. In general, plant operation in 1999 was practically as undisturbed and as reliable as in 1998, reflecting the ongoing tradition of careful maintenance that contributes so much to keeping the plants in excellent condition. However, due to exceptional outage activities at Beznau 2 (steam generator replacement) and an unplanned shut-down at Goesgen to replace a hydrogen seal on the main generator, 1999 nuclear production could not match that of the previous year. Also, record hydro power production caused the nuclear share in total electricity production to drop. With the exception of Beznau 2, all refueling and maintenance outages were once again short. The Leibstadt outage lasted 26 days, Goesgen 33 days, Beznau 1 lasted 29 days, Beznau 2 89 days and Muehleberg 27 days. At Goesgen, MOX fuel was loaded for the third time in 1999. Of the 44 freshly-loaded fuel elements, 20 were MOX elements. Non-electrical energy supplies from the Beznau and Goesgen nuclear power plants functioned flawlessly. Beznau fed 143.6 GWh of heat energy into the Refuna district heating system, while Goesgen supplied 169 GWh of process heat to the neighboring Niedergoesgen cardboard factory. At the end of 1999 and the beginning of 2000 all Swiss nuclear units continued to operate flawlessly - notwithstanding the challenges posed by the 'Lothar' storm that hit Western Europe in late December and the so-called Y2K computer bug that threatened to hit shortly afterwards, during the 'millennial' change-over. (authors)

  14. Summary of Operating Experience in Swiss Nuclear Power Plants 1999

    2000-05-01

    The five Swiss nuclear power units produced a net total of 23.6 TWh of electricity in 1999 - not as high as the all-time record (24.45 TWh in 1998), but nonetheless a solid operational performance. The nuclear share in overall electricity production was 35.3%, again lower than the previous year's 40%. In general, plant operation in 1999 was practically as undisturbed and as reliable as in 1998, reflecting the ongoing tradition of careful maintenance that contributes so much to keeping the plants in excellent condition. However, due to exceptional outage activities at Beznau 2 (steam generator replacement) and an unplanned shut-down at Goesgen to replace a hydrogen seal on the main generator, 1999 nuclear production could not match that of the previous year. Also, record hydro power production caused the nuclear share in total electricity production to drop. With the exception of Beznau 2, all refueling and maintenance outages were once again short. The Leibstadt outage lasted 26 days, Goesgen 33 days, Beznau 1 lasted 29 days, Beznau 2 89 days and Muehleberg 27 days. At Goesgen, MOX fuel was loaded for the third time in 1999. Of the 44 freshly-loaded fuel elements, 20 were MOX elements. Non-electrical energy supplies from the Beznau and Goesgen nuclear power plants functioned flawlessly. Beznau fed 143.6 GWh of heat energy into the Refuna district heating system, while Goesgen supplied 169 GWh of process heat to the neighboring Niedergoesgen cardboard factory. At the end of 1999 and the beginning of 2000 all Swiss nuclear units continued to operate flawlessly - notwithstanding the challenges posed by the 'Lothar' storm that hit Western Europe in late December and the so-called Y2K computer bug that threatened to hit shortly afterwards, during the 'millennial' change-over. (authors)

  15. Operating experience with diesel generators in Belgian nuclear power plants

    Merny, R. [Association Vincotte, Avenue du Roi 157, B-1060 Bruxelles/Brussels (Belgium)

    1986-02-15

    Various problems have occurred on the diesel generators in the Belgian nuclear power plants, independently of the D.G. manufacturer or from the operating crew. Furthermore no individual part of the D.G. can be incriminated as being the main cause of the incidents. The incidents reported in this paper are chosen because of the importance for the safety or for the long repair period. The unavailability of a D.G. can only be detected by periodic tests and controls. Combined with a good preventive maintenance, the risks of incidents can be reduced. (author)

  16. Operating experience with diesel generators in Belgian nuclear power plants

    Merny, R.

    1986-01-01

    Various problems have occurred on the diesel generators in the Belgian nuclear power plants, independently of the D.G. manufacturer or from the operating crew. Furthermore no individual part of the D.G. can be incriminated as being the main cause of the incidents. The incidents reported in this paper are chosen because of the importance for the safety or for the long repair period. The unavailability of a D.G. can only be detected by periodic tests and controls. Combined with a good preventive maintenance, the risks of incidents can be reduced. (author)

  17. The ASDEX Upgrade ICRF system: Operational experience and developments

    Faugel, H.; Angene, P.; Becker, W.; Braun, F.; Bobkov, Vl.V.; Eckert, B.; Fischer, F.; Hartmann, D.A.; Heilmaier, G.; Kneidl, J.; Noterdaeme, J.-M.; Siegl, G.; Wuersching, E.

    2005-01-01

    The ICRF system at the ASDEX Upgrade tokamak is in operation since May 1992. Following some modifications of which the major one was the installation of 3 dB couplers it has become a reliable additional heating system. The maximum power coupled into the plasma has been raised up to 7.2 MW (90% of the installed RF power) for short pulses and up to 6.2 MW for pulses several second long with energy of up to 29 MJ. A power of 5 MW is delivered on a regular basis to replace two NBI sources

  18. Air-operated valve diagnostics: requirements, programmes and experiences

    Cervilla, Remedios; Vallana, Fernando; Laporta, Jose Maria

    2014-01-01

    The aim of this paper is to present some elements in the field of air-operated valve (AOV) diagnostics from the perspective of Tecnatom, as a testing services provider in the national and international nuclear park. Throughout the following lines, we summarize the regulatory framework existing in Spain and the current practices in Spanish nuclear power plants regarding the AOV programs, the role of Tecnatom as a service provider and our testing techniques. Finally, a real test case is presented, to illustrate the value of diagnostic as predictive maintenance and early degradation detection tool. (authors)

  19. Operation and maintenance experience at the TRIGA Mainz reactor

    Menke, Helmut

    1976-01-01

    Oscillations observed in the linear power channel especially at low steady state power with the pulse-rod in down position were found to be due to wear of connections of the pulse-rod. The downstream water from the cooling system caused a swing of the rod, which in turn induced the power oscillations. The wear can be regarded as normal, as more than 10,000 pulses have been performed so far. The repairs of the rod assembly are described. No major problems in operation and maintenance of the TRIGA Mainz were met since 1974. Results of routine inspections as fuel element measurements, power calibrations, etc., are described and discussed. (author)

  20. Safety evaluation by living probabilistic safety assessment. Procedures and applications for planning of operational activities and analysis of operating experience

    Johanson, Gunnar; Holmberg, J.

    1994-01-01

    Living Probabilistic Safety Assessment (PSA) is a daily safety management system and it is based on a plant-specific PSA and supporting information systems. In the living use of PSA, plant status knowledge is used to represent actual plant safety status in monitoring or follow-up perspective. The PSA model must be able to express the risk at a given time and plant configuration. The process, to update the PSA model to represent the current or planned configuration and to use the model to evaluate and direct the changes in the configuration, is called living PSA programme. The main purposes to develop and increase the usefulness of living PSA are: Long term safety planning: To continue the risk assessment process started with the basic PSA by extending and improving the basic models and data to provide a general risk evaluation tool for analyzing the safety effects of changes in plant design and procedures. Risk planning of operational activities: To support the operational management by providing means for searching optimal operational maintenance and testing strategies from the safety point of view. The results provide support for risk decision making in the short term or in a planning mode. The operational limits and conditions given by technical specifications can be analyzed by evaluating the risk effects of alternative requirements in order to balance the requirements with respect to operational flexibility and plant economy. Risk analysis of operating experience: To provide a general risk evaluation tool for analyzing the safety effects of incidents and plant status changes. The analyses are used to: identify possible high risk situations, rank the occurred events from safety point of view, and get feedback from operational events for the identification of risk contributors. This report describes the methods, models and applications required to continue the process towards a living use of PSA. 19 tabs, 20 figs

  1. Swiss operating experience: availability and post-Chernobyl upgrading

    Wenger, H.

    1988-01-01

    Switzerland started its era of nuclear power with the foundation stone for the country's first nuclear power unit (Beznau-1) onSeptember 6, 1965. Up to that date, Switzerland was the classic country for hydropower, negligible amounts of electricity being produced by fossil-fuelled plants. Today, nuclear accounts for close to 40 % of Swiss total electricity generation. Whwn credits for lifetime capacity factors of each individual plant are combined, Switzerland tops the world list for light water reactor performance over many years. The Chernobyl reactor type RBMK-1000 has very little in common with the light water reactors operating in Switzerland, so one would certainly not expect any direct influence on Swiss plant design, operation or maintenance as an immediate consequence of the accident. Some important safety measures against severe accidents are currently being implemented. These measures were not a direct outcome of the Chernobyl accident and were already in discussion quite some time before. With this action, the proper position of nuclear power to meet the ever increasing demand for electricity in Switzerland will hopefully again find greater public acceptance. 1 tab

  2. Thirty year operational experience of the JET flywheel generators

    Rendell, Daniel, E-mail: dan.rendell@ccfe.ac.uk; Shaw, Stephen R.; Pool, Peter J.; Oberlin-Harris, Colin

    2015-10-15

    Highlights: • The pony-motor rotor circuit's liquid resistor requires frequent maintenance. • A crowned profile on the thrust pads is desirable. • Both plug braking transformers have been replaced after flashovers occurred. • Two-plane balancing of one of the flywheel generators has improved vibration levels but also provided information to lead further investigations. • A half-life inspection on the flywheel generators has shown no major issues after 30 year of operating. - Abstract: The JET flywheel generator converters have operated since 1983 and for over 85,000 pulses. Problems with this plant are discussed, including corrosion, unbalanced flow and arcing within the liquid resistors; starting difficulties on both machines; and failure of the plug-braking transformers at energisiation. In 2012/13 two sets of thrust bearing pads have required refurbishment, a process which highlighted the importance of their profile. Extensive half-life inspections have shown that there are no serious problems with either generator.

  3. Operating and maintenance experience of Dhruva secondary shutdown system

    Sharma, U.L.; Bharathan, R.

    1997-01-01

    Nine numbers of cadmium shut-off rods are used as primary fast acting shutdown devices while moderator dumping is used as secondary shutdown system. The secondary shutdown system in Dhruva reactor comprises of 3 dump valves and 3 control valves. Under normal operations, the control valves are used to control the moderator level and thereby the reactor power. Under Trip conditions the dump valves as well as the control valves open fully, dumping the moderator to the dump tank, thereby acting as secondary shutdown devices. While the failure of any of these valves to close fully is an incident, the failure of any of these valves to open on a demand is a safety related unusual occurrence and needs to be viewed seriously. During the last 11 years of operation of these valves, there was one incidence of a valve not closing fully and there were two instances of a valve not opening fully on demand. The possible causes, the corrective action taken to rehabilitate these valves and the elaborate system preparations undertaken to enable maintenance jobs are described. (author)

  4. Velocities in a Centrifugal PAT Operation: Experiments and CFD Analyses

    Mariana Simão

    2017-12-01

    Full Text Available Velocity profiles originated by a pump as turbine (PAT were measured using an ultrasonic doppler velocimetry (UDV. PAT behavior is influenced by the velocity data. The effect of the rotational speed and the associated flow velocity variations were investigated. This research focuses, particularly, on the velocity profiles achieved for different rotational speeds and discharge values along the impeller since that is where the available hydraulic power is transformed into the mechanical power. Comparisons were made between experimental test results and computational fluid dynamics (CFD simulations. The used CFD model was calibrated and validated using the same conditions as the experimental facility. The numerical simulations showed good approximation with the velocity measurements for different cross-sections along the PAT system. The application of this CFD numerical model and experimental tests contributed to better understanding the system behavior and to reach the best efficiency operating conditions. Improvements in the knowledge about the hydrodynamic flow behavior associated with the velocity triangles contribute to improvements in the PAT concept and operation.

  5. Ganges Valley Aerosol Experiment: Science and Operations Plan

    Kotamarthi, VR

    2010-06-21

    The Ganges Valley region is one of the largest and most rapidly developing sections of the Indian subcontinent. The Ganges River, which provides the region with water needed for sustaining life, is fed primarily by snow and rainfall associated with Indian summer monsoons. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers can be immense. Recent satellite-based measurements have indicated that the upper Ganges Valley has some of the highest persistently observed aerosol optical depth values. The aerosol layer covers a vast region, extending across the Indo-Gangetic Plain to the Bay of Bengal during the winter and early spring of each year. The persistent winter fog in the region is already a cause of much concern, and several studies have been proposed to understand the economic, scientific, and societal dimensions of this problem. During the INDian Ocean EXperiment (INDOEX) field studies, aerosols from this region were shown to affect cloud formation and monsoon activity over the Indian Ocean. This is one of the few regions showing a trend toward increasing surface dimming and enhanced mid-tropospheric warming. Increasing air pollution over this region could modify the radiative balance through direct, indirect, and semi-indirect effects associated with aerosols. The consequences of aerosols and associated pollution for surface insolation over the Ganges Valley and monsoons, in particular, are not well understood. The proposed field study is designed for use of (1) the ARM Mobile Facility (AMF) to measure relevant radiative, cloud, convection, and aerosol optical characteristics over mainland India during an extended period of 9–12 months and (2) the G-1 aircraft and surface sites to measure relevant aerosol chemical, physical, and optical characteristics in the Ganges Valley during a period of 6–12 weeks. The aerosols in this region have complex sources, including burning of coal, biomass, and biofuels; automobile

  6. Operating experience from Swedish nuclear power plants, 1999

    NONE

    2000-07-01

    The total generation of electricity from Swedish nuclear power plants was 70.1 TWh during 1999, which is slightly more than the mean value for the last five years. The total electricity consumption decreased by one percent, compared with 1998, to a total of 142.3 TWh, due to an unusually warm summer and autumn. The abundant supply of hydroelectric power resulted in comparatively extensive load-following operation by the nuclear plants during the year. Production losses due to low demand totalled 3.0 TWh. The closure of Barsebaeck 1 will result in a capacity reduction exceeding 4 TWh per year. The hydroelectric power production was 70 TWh, which was 6 TWh more than during a normal year, i.e. a year with average rainfall. The remaining production sources, mainly from solid fuel plants combined with district heating contributed 9 TWh. Electricity generation by means of wind power is still increasing. There are now about 470 wind power stations, which produced 0.3 TWh during the year. The total electricity generation totalled 149.8 TWh, a three percent decrease compared with 1998. The preliminary figures for export were 15.9 TWh and for import 8.4 TWh. The figures above are calculated from the preliminary production result. A comprehensive report on electric power supply and consumption in Sweden is provided in the 1999 Annual Report from the Swedish Power Association. The unit capability factor for the PWRs at Ringhals averaged 91%, while the BWRs averaged 82% mainly due to the extended outages. The BWR reactors at Forsmark averaged as much as 93%. Forsmark 1 experienced the shortest refuelling outage ever in Sweden, only 9 days and 20 hours. In May, Oskarshamn 2 passed a historical milestone - the unit produced 100 TWh since connection to the grid in 1974. The final production day for Barsebaeck 1, which had been in commercial operation since 1975, was on November 30 when a decision by the Swedish Government revoked the operating licence. Three safety-related events

  7. Operative management of Marfan syndrome: The Johns Hopkins experience.

    Baumgartner, W A; Cameron, D E; Redmond, J M; Greene, P S; Gott, V L

    1999-06-01

    Doctor Antoine Marfan described the first case of Marfan syndrome in 1896. It was over 50 years later that the development of aortic aneurysms and subsequent rupture was appreciated as the most life-threatening component of the syndrome. Doctor Vincent Gott, at our institution, performed the first Bentall procedure for an aneurysm of the ascending aorta in 1976. Since that time, the aortic root has been replaced in 231 Marfan patients. Of this group, 218 patients had a composite graft repair, 11 had an aortic root replacement with a homograft, and 2 patients had valve sparing procedures. There were 168 males and 63 females. Of the total 231 patients, 150 were operated on by Dr Gott. The remaining 81 patients were operated on by 10 other Hopkins surgeons. The average diameter of the ascending aorta was 6.8 cm, with a range from 4.5 to 10. The average aortic diameter of 43 patients who had an ascending aortic dissection was 7.3 cm. Fourteen of these patients had dissection with an aortic diameter of 6.5 cm or less. Among the 198 patients who underwent elective repair, there was no 30-day mortality. Thirty-three patients underwent urgent repair with 2 deaths, yielding a 30-day mortality of 6.1%. The mortality for the entire group of patients was 0.9%. Complications associated with this series of patients included 8 with endocarditis, 7 with thromboembolism, and 4 late coronary dehiscences. Actuarial survival was 88% at 5 years, 81% at 10 years, and 75% at 20 years. Multivariate analysis revealed New York Heart Association classification, male gender and urgent surgery as independent risk factors for mortality. Marfan patients with aortic aneurysms can undergo elective surgery with a low operative risk and excellent long-term survival with low morbidity. We feel that elective resection of an aneurysm in a Marfan patient should occur when it approaches a diameter of 5.5 cm. It is essential that a timely diagnosis be made in this group of young patients.

  8. Operational experiences with automated acoustic burst classification by neural networks

    Olma, B.; Ding, Y.; Enders, R.

    1996-01-01

    Monitoring of Loose Parts Monitoring System sensors for signal bursts associated with metallic impacts of loose parts has proved as an useful methodology for on-line assessing the mechanical integrity of components in the primary circuit of nuclear power plants. With the availability of neural networks new powerful possibilities for classification and diagnosis of burst signals can be realized for acoustic monitoring with the online system RAMSES. In order to look for relevant burst signals an automated classification is needed, that means acoustic signature analysis and assessment has to be performed automatically on-line. A back propagation neural network based on five pre-calculated signal parameter values has been set up for identification of different signal types. During a three-month monitoring program of medium-operated check valves burst signals have been measured and classified separately according to their cause. The successful results of the three measurement campaigns with an automated burst type classification are presented. (author)

  9. Operational features and microwave characteristics of the Vircator II experiment

    Price, D.; Fittinghoff, O.; Benford, J.; Sze, H.; Woo, W.

    1988-01-01

    The Vircator II oscillating virtual-cathode microwave source operates with diode voltages between 600 and 800 kV and diode current between 50 and 120 kA. Maximal microwave output power between 200 and 500 MW is achieved when the diode aspect ratio, cathode surface, charge voltage, and extraction coupling are arranged to simultaneously 1) maximize diode voltage, 2) satisfy magnetic insulation criteria, 3) avoid nonuniform or unstable electron emission, and 4) optimize microwave transmission from the virtual cathode to the launching antenna. Broad-band radiation between 0.4 and 5.5 GHz is generated. The central frequency follows the beam plasma frequency. It is tuned by varying the current density with anode-cathode (A-K) gap adjustments

  10. Swedish spent fuel management systems, facilities and operating experiences

    Vogt, J.

    1998-01-01

    About 50% of the electricity in Sweden is generated by means of nuclear power from 12 LWR reactors located at four sites and with a total capacity of 10,000 MW. The four utilities have jointly created SKB, the Swedish Nuclear Fuel and Waste Management Company, which has been given the mandate to manage the spent fuel and radioactive waste from its origin at the reactors to the final disposal. SKB has developed a system for the safe handling of all kinds of radioactive waste from the Swedish nuclear power plants. The keystones now in operation of this system are a transport system, a central interim storage facility for spent nuclear fuel (CLAB), a final repository for short-lived, low and intermediate level waste (SFR). The remaining, system components being planned are an encapsulation plant for spent nuclear fuel and a deep repository for encapsulated spent fuel and other long-lived radioactive wastes. (author)

  11. Diamond Ordinance Radiation Facility (DORF) reactor operating experiences

    Gieseler, Walter

    1970-01-01

    The Diamond Ordnance Radiation Facility Mark F Reactor is described and some of the problems encountered with its operation are discussed. In a period from reactor startup in September 1961 to June 1964, when the aluminum-clad core was changed to a stainless-steel clad core, a total of 30 fuel elements were removed from reactor service because of excessive growth. One leaking fuel element was detected during the lifetime of the aluminum- clad core. In June 1964, the core was changed to the stainless-steel-clad high hydride fuel elements. Since the installation of the stainless-steel-clad fuel element core, there has been a gradual decline of excess reactivity. Various theories were discussed as the cause but the investigations have resulted in no definitive conclusion that could account for the total reactivity loss

  12. Operational experience with the control scheme for IUAC linac booster

    Sahu, B.K.; Antony, J.; Mathuria, D.S.; Pandey, A.; Ghosh, S.; Mehta, R.; Rai, A.; Patra, P.; Choudhury, G.K.; Singh, K.; Ajith Kumar, B.P.; Kanjilal, D.; Roy, A.

    2009-01-01

    Accelerated beam from the first superconducting linear accelerator (linac) module of IUAC has been delivered to the user. The linac control scheme has worked successfully with the existing pelletron control scheme. Local RF control system consisting of Resonator controller and supporting RF modules are used for multipactoring conditioning, high power pulse conditioning and for the phase/amplitude locking of the superconducting resonators. Beam acceleration is done by adjusting the RF phase of each resonator with respect to master oscillator. The automation of control scheme is planned for smooth operation of linac with minimum human intervention. Python software support is added for writing automation routines in present control system software. An alternate tuning mechanism based on piezoelectric actuators has been successfully tested. (author)

  13. Operational experience with the Sizewell B integrated plant computer system

    Ladner, J.E.J.; Alexander, N.C.; Fitzpatrick, J.A.

    1997-01-01

    The Westinghouse Integrated System for Centralised Operation (WISCO) is the primary plant control system at the Sizewell B Power Station. It comprises three subsystems; the High Integrity Control System (HICS), the Process Control System (PCS) and the Distributed Computer system (DCS). The HICS performs the control and data acquisition of nuclear safety significant plant systems. The PCS uses redundant data processing unit pairs. The workstations and servers of the DCS communicate with each other over a standard ethernet. The maintenance requirements for every plant system are covered by a Maintenance Strategy Report. The breakdown of these reports is listed. The WISCO system has performed exceptionally well. Due to the diagnostic information presented by the HICS, problems could normally be resolved within 24 hours. There have been some 200 outstanding modifications to the system. The procedure of modification is briefly described. (A.K.)

  14. MagLev Cobra: Test Facilities and Operational Experiments

    Sotelo, G G; Dias, D H J N; De Oliveira, R A H; Ferreira, A C; De Andrade, R Jr; Stephan, R M

    2014-01-01

    The superconducting MagLev technology for transportation systems is becoming mature due to the research and developing effort of recent years. The Brazilian project, named MagLev-Cobra, started in 1998. It has the goal of developing a superconducting levitation vehicle for urban areas. The adopted levitation technology is based on the diamagnetic and the flux pinning properties of YBa 2 Cu 3 O 7−δ (YBCO) bulk blocks in the interaction with Nd-Fe-B permanent magnets. A laboratory test facility with permanent magnet guideway, linear induction motor and one vehicle module is been built to investigate its operation. The MagLev-Cobra project state of the art is presented in the present paper, describing some construction details of the new test line with 200 m.

  15. Operating experience with the Cornell University TRIGA reactor

    Aderhold, H.C.

    1970-01-01

    As a result of our investigations, we believed the damage to be mechanical in origin and not to cladding failure. A new handling tool of modified design was put into service in July 1963, and since that time one element S/N 3075 has been dropped. This we believe was caused by operator error. At the request of prospective users, a high intensity, high energy gamma-ray irradiation facility has been added to the TRIGA equipment. This apparatus is simple to construct and use, either temporarily or permanently, with the TRIGA. Adjustment of relative neutron and gamma ray fluxes is possible by either shielding or changing rate of water flow. No attempt was made to improve performance by guiding water flow through the core, and higher yields should be obtainable by this means and by increasing the size of the holdup tank

  16. Operating experience from Swedish nuclear power plants 2001

    NONE

    2002-07-01

    The total production of electricity from Swedish nuclear power plants was 69.2 TWh during 2001, which is an increase of more than 25% compared to 2000. The hydroelectric power production increased to 78.3 TWh, 22% more than during a normal year, i.e. a year with average rainfall. Wind power contributed 0.5 TWh, and remaining production sources, mainly from solid fuel plants combined with district heating, contributed 9.6 TWh. The electricity generation totalled 157.6 TWh, the highest annual production to date. The preliminary figures for export were 18.5 TWh and and for import 11.1 TWh. Operational statistics are presented for each Swedish reactor. Two events, given INES level 1 rating, are reported from Barsebaeck 2 and Ringhals 2.

  17. Experiments and simulation of high current operation at CEBAF

    Merminga, L.; Crawford, K.; Delayen, J.R.; Doolittle, L.; Hovater, C.; Kazimi, R.; Krafft, G.; Reece, C.; Simrock, S.; Tiefenback, M.; Wang, D.X.

    1996-01-01

    The superconducting rf, cw electron accelerator at CEBAF has achieved the design energy of 4 GeV using 5-pass recirculation through a pair of 400 MeV linacs. Stable beam current of 35 μA has been delivered to the Experimental Hall C. The total beam current that has been recirculated so far is 248 μA. Measurements of the performance of the rf control system have been made in both pulsed and cw mode, and a numerical model has been developed which describes the beam-cavity interaction, includes a realistic representation of low level controls, klystron characteristics and microphonic noise. Experimental data and simulation results on transient beam loading, klystron saturation, a new technique for cavity phasing, and heavy beam loading tests are described; in conclusion, an outlook on full current operation is presented

  18. Operating experience feedback report: Technical specifications: Commercial power reactors

    O'Reilly, P.D.; Plumlee, G.L. III.

    1989-03-01

    This report documents a trends and patterns analysis of technical specification (TS)-related licensee event reports (LERs) conducted by the Nuclear Regulatory Commission's (NRC's) Office for Analysis and Evaluation of Operational Data (AEOD). The objectives of this analysis were (1) to identify and catalog technical specification-related LERs, (2) to categorize and evaluate the events reported in these a LERs, (3) to identify any issues arising from the evaluation which appear to have generic safety significance, or which relate to the on-going Technical Specification Improvement Program, and (4) to trend the results obtained from the analysis of the data obtained in (1) through (3). 9 refs., 9 figs., 22 tabs

  19. MagLev Cobra: Test Facilities and Operational Experiments

    Sotelo, G. G.; Dias, D. H. J. N.; de Oliveira, R. A. H.; Ferreira, A. C.; De Andrade, R., Jr.; Stephan, R. M.

    2014-05-01

    The superconducting MagLev technology for transportation systems is becoming mature due to the research and developing effort of recent years. The Brazilian project, named MagLev-Cobra, started in 1998. It has the goal of developing a superconducting levitation vehicle for urban areas. The adopted levitation technology is based on the diamagnetic and the flux pinning properties of YBa2Cu3O7-δ (YBCO) bulk blocks in the interaction with Nd-Fe-B permanent magnets. A laboratory test facility with permanent magnet guideway, linear induction motor and one vehicle module is been built to investigate its operation. The MagLev-Cobra project state of the art is presented in the present paper, describing some construction details of the new test line with 200 m.

  20. Operational experience for liquid radioactive waste in FR Yugoslavia

    Plecas, I.; Pavlovic, R.; Pavlovic, S.

    2003-01-01

    The present paper reports the results of the preliminary removal of sludge from the bottom of the spent fuel storage pool in the RA reactor, mechanical filtration of the pool water and sludge conditioning and storage. Yugoslavia is a country without a nuclear power plant (NPP) on its territory. The law which strictly forbids NPP construction is still valid, but, nevertheless we must handle and dispose radioactive waste. In the last forty years, in the ''Vinca'' Institute, as a result of two research reactors being operational, named RA and RB, and as a result of the application of radionuclides in medicine, industry and agriculture, radioactive waste materials of different levels of specific activity were generated. As a temporary solution, radioactive waste materials are stored in two interim storages. Radwaste materials that were immobilized in the inactive matrices are to be placed in concrete containers, for further manipulation and disposal. (orig.)

  1. Operating experience from Swedish nuclear power plants 2001

    2002-01-01

    The total production of electricity from Swedish nuclear power plants was 69.2 TWh during 2001, which is an increase of more than 25% compared to 2000. The hydroelectric power production increased to 78.3 TWh, 22% more than during a normal year, i.e. a year with average rainfall. Wind power contributed 0.5 TWh, and remaining production sources, mainly from solid fuel plants combined with district heating, contributed 9.6 TWh. The electricity generation totalled 157.6 TWh, the highest annual production to date. The preliminary figures for export were 18.5 TWh and and for import 11.1 TWh. Operational statistics are presented for each Swedish reactor. Two events, given INES level 1 rating, are reported from Barsebaeck 2 and Ringhals 2

  2. First operation experiences with ITER-FEAT model pump

    Mack, A.; Day, Chr.; Haas, H.; Murdoch, D.K.; Boissin, J.C.; Schummer, P.

    2001-01-01

    Design and manufacturing of the model cryopump for ITER-FEAT have been finished. After acceptance tests at the contractor's premises the pump was installed in the TIMO-facility which was prepared for testing the pump under ITER-FEAT relevant operating conditions. The procedures for the final acceptance tests are described. Travelling time, positioning accuracy and leak rate of the main valve are within the requirements. The heat loads to the 5 and 80 K circuits are a factor two better than the designed values. The maximum pumping speeds for H 2 , D 2 , He, Ne were measured. The value of 58 m 3 /s for D 2 is well above the contractual required value of 40 m 3 /s

  3. Operating experience from Swedish nuclear power plants 2002

    NONE

    2003-07-01

    The total production of electricity from Swedish nuclear power plants was 65.6 TWh during 2002, which is a decrease compared to 2001. The energy capability factor for the 11 Swedish reactors averaged 80.8%. The PWRs at Ringhals averaged 87.6%, while the BWRs, not counting Oskarshamn 1, reached 89.2%. No events, which in accordance to conventions should be reported to IAEA, have occurred during 2002. Operational statistics are presented for each Swedish reactor. The hydroelectric power was 66 TWh, 16% lower than 2000. Wind power contributed 0.5 TWh, and remaining production sources, mainly from solid fuel plants combined with district heating, contributed 10.9 TWh. The electricity generation totalled 143 TWh, considerably less than the record high 2001 figure of 158.7 TWh. The preliminary figures for export were 14.8 TWh and and for import 20.1 TWh.

  4. Steam generator operating experience: Update for 1984-1986

    Frank, L.; Stokley, J.

    1988-06-01

    This report summarizes operational events and degradation mechanisms affecting pressurized water reactor steam generator integrity, provides updated inspection results reported in 1984, 1985, and 1986, and highlights both prevalent problem areas and advances in improved equipment test practices, preventive measures, repair techniques, and replacement procedures. It describes equipment design features of the three major suppliers and discusses 68 plants in detail. Steam generator degradation mechanisms include intergranular stress corrosion cracking, primary water stress corrosion cracking, pitting, intergranular attack, and vibration wear that effects tube integrity and causes leakage. Plugging, sleeving heat treatment, peening, chemical cleaning, and steam generator replacements are described and regulatory instruments and inspection guidelines for nondestructive evaluations and girth weld cracking are discusses. The report concludes that although degradation mechanisms are generally understood, the elimination of unscheduled plant shutdowns and costly repairs resulting from leaking tubes has not been achieved. Highlights of steam generator research and unresolved safety issues are discussed. 21 refs., 8 tabs

  5. Operating experience 1993 in Swedish nuclear power plants

    1995-01-01

    For many years, the Swedish nuclear power plants had a very good track record, compared with the international average. This trend was broken in 1993. During the year, six power plants were shut down for extended periods of time, for different safety-related reasons. During the autumn, a reactor containment leak was detected during scheduled containment leak rate testing at Barsebaeck 2. The unit was shut down for extensive investigation and corrective action for the rest of the year. Ringhals 2 was shut down last six months of the year as crack indications were found in a weld next to a control rod penetration in the reactor vessel head. Extensive tests and analyses revealed that the crack originated from the manufacturing of the vessel head and was of minor importance to safety. Oskarshamn 1 was shut down the whole year. Cracks in cold bent pipes in the residual heat removal system and cracks in the feedwater riser pipes lead to extensive replacement of piping, including pipes inside the reactor vessel. Decontamination of the reactor vessel was successful and attracted world wide interest. A programme for plant status verification was started in order to establish long-term operating conditions. Replacement of the pipe insulation and the inlet strainers in the core and containment spray systems solved the problems with clogging at certain failures in Barsebaeck, Ringhals 1 and Oskarshamn 1 and 2. Six of the reactors had an extremely high availability, of about 90 per cent and more. By year end, eleven of the twelve reactors were in full power operation

  6. Operational experience with Dragon reactor experiment of relevance to commercial reactors

    Capp, P.D.; Simon, R.A.

    1976-01-01

    An important part of the experience gained during the first ten years of successful power operation of the Dragon Reactor is relevant to the design and operation of future High Temperature Reactors (HTRs). The aspects presented in this paper have been chosen as being particularly applicable to larger HTR systems. Core performance under a variety of conditions is surveyed with particular emphasis on a technique developed for the identification and location of unpurged releasing fuel and the presence of activation and fission products in the core area. The lessons learned during the reflector block replacement are presented. Operating experience with the primary circuit identifies the lack of mixing of gas streams within the hot plenum and the problems of gas streaming in ducts. Helium leakage from the circuit is often greater than the optimum 0.1%/d. Virtually all the leakage problems are associated with the small bore instrument pipework essential for the many experiments associated with the Dragon Reactor Experiment (DRE). Primary circuit maintenance work confirms the generally clean state of the DRE circuit but identifies 137 Cs and 110 Agsup(m) as possible hazards if fuel emitting these isotopes is irradiated. (author)

  7. Nuclear Power Plant Operating Experience from the IAEA/NEA International Reporting System for Operating Experience, 2005-2008

    2010-06-01

    The fundamental objective of the Incident Reporting System (IRS) is to contribute to improving the safety of commercial nuclear power plants which are operated worldwide. This fourth publication, covering the period 2005-2008, follows on the success of the previous three. It highlights important lessons learned based on a review of the approximately 200 event reports received from the participating countries over this period. The book is written both for a non-technical audience and for senior officials in industry and government who have decision making roles in the nuclear power industry.

  8. HFETR operation management

    Liu Rong; Yang Shuchun; Peng Jun; Zhou Shoukang

    2003-01-01

    Experiences and work methods with High Flux Engineering Test Reactor (HFETR) operation are introduced, which have been accumulated in a long period of operation, in the aspects as reactor operation, test, maintenance, operator training and incident management. It's clear that the safety operation of HFETR has been ensured, and the methods are valid. (authors)

  9. Spacecraft operations

    Sellmaier, Florian; Schmidhuber, Michael

    2015-01-01

    The book describes the basic concepts of spaceflight operations, for both, human and unmanned missions. The basic subsystems of a space vehicle are explained in dedicated chapters, the relationship of spacecraft design and the very unique space environment are laid out. Flight dynamics are taught as well as ground segment requirements. Mission operations are divided into preparation including management aspects, execution and planning. Deep space missions and space robotic operations are included as special cases. The book is based on a course held at the German Space Operation Center (GSOC).

  10. The Pajarito Site operating procedures for the Los Alamos Critical Experiments Facility

    Malenfant, R.E.

    1991-12-01

    Operating procedures consistent with DOE Order 5480.6, and the American National Standard Safety Guide for the Performance of Critical Experiments are defined for the Los Alamos Critical Experiments Facility (LACEF) of the Los Alamos National Laboratory. These operating procedures supersede and update those previously published in 1983 and apply to any criticality experiment performed at the facility. 11 refs

  11. ATLAS Strip Detector: Operational Experience and Run1-> Run2 Transition

    Nagai, Koichi; The ATLAS collaboration

    2014-01-01

    Large hadron collider was operated very successfully during the Run1 and provided a lot of opportunities of physics studies. It currently has a consolidation work toward to the operation at $\\sqrt{s}=14 \\mathrm{TeV}$ in Run2. The ATLAS experiment has achieved excellent performance in Run1 operation, delivering remarkable physics results. The SemiConductor Tracker contributed to the precise measurement of momentum of charged particles. This paper describes the operation experience of the SemiConductor Tracker in Run1 and the preparation toward to the Run2 operation during the LS1.

  12. Bohunice V-1. Review of safety upgrading and operating experiences

    Korec, J.; Kuschel, D.

    2000-01-01

    The Bohunice site in the Slovak Republic has two Russian-designed twin-unit nuclear power plants, one equipped with reactors of the WWER 440/230 type, the other with type WWER 440/213 reactors. Two older units (V-1) started commercial operation in late 1978 and 1980 respectively and have been supplying electricity to the national grid since that time without any events that could have degraded plant safety level. In the period prior to 1990 the utility Slovenske Elektrarne (S.E.) performed extensive modifications and upgrades to the original design of the two older units V-1 NPP. Furthermore, significant steps in safety improvement for Bohunice NPP V-1 have been made since 1990. Following the political restructuring of the former Czechoslovakia and the country's new open-door policy towards western organizations, several international expert missions were focused on evaluation of Bohunice NPP safety status level and operational reliability, particularly targeting the two older units. Based on recommendations of individual expert missions and complementary deterministic and probabilistic safety analyses performed by S.E., the Czechoslovak Nuclear Regulatory Authority issued the Resolution No. 5/91 defining 81 measures concerning further safety and reliability improvement of Bohunice V1 .A range of short-term and long-term upgrades was prioritised in terms of importance to plant safety and work to implement these measures commenced in the early nineties. During the 'Small Reconstruction' from 1991 to 1993 some of the short term upgrading measures were realized to eliminate the most serious safety deficits, thus to achieve a significant reduction in core damage frequency and a major improvement in confinement integrity. In this paper and presentation the goals of the gradual reconstruction project, basic engineering, detailed engineering and realization, last major stage of Unit 2 upgrade, as well as final stage of Unit 1 upgrade in early 2000 are presented

  13. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    Miller, M.H. [Duke Power Co., Seneca, SC (United States)

    1995-04-01

    The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT{trademark} Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS.

  14. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    Miller, M.H.

    1995-01-01

    The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT trademark Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS

  15. How to ensure the safety of extended operations: Practice and experience of Paks NPP

    Kovacs, J.

    2005-01-01

    The Paks Nuclear Power Plant strategy is to extend the operational lifetime of the plant and renew the operational license for 20 years over the designed and licensed lifetime. In the paper the preconditions of long-term operation are discussed and the basic findings and experience of the license renewal works are also presented. The further plans fo NPP Paks for ensuring safe operation in long-term are discussed. (author)

  16. Operating experience with nuclear power plants 2013; Betriebserfahrungen mit Kernkraftwerken 2013

    Anon.

    2014-07-01

    The VGB Technical Committee 'Nuclear Plant Operation' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2013, events important to plant safety, special and relevant repair, and retrofit measures from Belgium, Germany, Finland, the Netherlands, Switzerland, and Spain. (orig.)

  17. Operator substitution

    Hautus, M.L.J.

    1994-01-01

    Substitution of an operator into an operator-valued map is defined and studied. A Bezout-type remainder theorem is used to derive a number of results. The tensor map is used to formulate solvability conditions for linear matrix equations. Some applications to system theory are given, in particular

  18. Operation amplifier

    Tetsuya, Saito; Nauta, Bram

    2008-01-01

    To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a differential amplifier circuit 1;

  19. Operation Amplifier

    Tetsuya, Saito; Nauta, Bram

    2011-01-01

    PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a

  20. Operation Amplifier

    Tetsuya, S.; Nauta, Bram

    2007-01-01

    PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. ; SOLUTION: The operation amplifier comprises: a

  1. Accelerator operations

    Anon.

    1979-01-01

    Operations of the SuperHILAC, the Bevatron/Bevalac, and the 184-inch Synchrocyclotron during the period from October 1977 to September 1978 are discussed. These include ion source development, accelerator facilities, the Heavy Ion Spectrometer System, and Bevelac biomedical operations

  2. Experience of operation of LWRs and subjects hereafter in Japan

    Toyota, Masatoshi

    1985-01-01

    The commercial nuclear power plants in operation in Japan are one gas-cooled reactor of 166 MW, 14 BWRs of 10,717 MW and 13 PWRs of 9,678 MW, in total, 28 plants of 20,561 MW. This value is 13 % of the total installed capacity of power generation and 20 % of generated output. Initially, LWR plants were imported from the U.S., but recently, the proportion of the domestic production has reached nearly 100 %. Initially, such troubles as the stress corrosion cracking of primary piping, the thermal fatigue cracking of feed water nozzles and the pin holes in fuel in BWRs, and the leak in steam generator tubes, the stress corrosion cracking of control rod-supporting pins, the bending of fuel rods and baffle jet in PWRs were encountered. Because of the clarification of the causes of these initial troubles and the establishment of the countermeasures, the capacity ratio in 1975-1977 was as low as about 40 %. However, in recent two years, it rose to more than 70 %. The countermeasures to raise the reliability and safety of nuclear power plants and to reduce radiation exposure are shown. The reduction of the construction cost is the most important problem. (Kako, I.)

  3. Operating experience from Swedish nuclear power plants, 2000

    NONE

    2001-07-01

    From a safety point of view, 2000 was - as were previous years - satisfactory. Total electricity production from the Swedish nuclear power stations amounted to 54.2 TWh, which was over 20% less than the 70.2 TWh produced in 1999. The two main reasons for the reduction were the closure of Barsebaeck 1 on 1st December 1999, and the cutback in output from all reactors due to the particularly good availability of hydro power in 2000. Some reactors were even shut down completely as a result of the low power demand, which has not happened previously. The quantity of unutilised production capacity as a result of these reductions amounted to 11.6 TWh. Costdown operation prior to the annual overhaul shutdowns, which makes better use of the fuel, represented a further 2.1 TWh of unutilised capacity. The average energy availability of the three PWRs at Ringhals was 82.0%, while that of the eight BWRs was 84.2%. Forsmark 3, Ringhals 3 and Oskarshamn 3 all had average availabilities of over 90%. Of five events with safety implications that occurred in the plants during the year, three are described under Special Reporting. One of them relates to the crack indications in welds that were found in an American PWR in the autumn, and which were subsequently also found in Ringhals 4.

  4. Operation experience with the TRIGA reactor of Pavia

    Lana, F.; Marchetti, F.; Losi, A.; Orvini, E.; Borio, A.; Salvini, A.

    2002-01-01

    Operational data for the reactor for the period 2000-2002 are presented as well as an account for the irradiations, irradiated samples and reactor time requests for different applications and different users. The ventilation system has been replaced in 2001 with a new system characterised by one way through air treatments by a double stock of filters and air release through seven absolute filters (EPA 99.99%) and expulsion engine powered by an inverter. The inverter is automatically managed by a PC Honeywell in order to have over 50 Pa of depression. There is also an emergency expulsion of the air through active carbon filters. The new ventilation parameters are presented and compared to the previous values (before 2001). An account for the fuel element in the core and spent fuel elements is given. During the refuelling six new SST cladding elements have been placed in the reactor core. Configuration fuel elements have been rearranged in order to have Ring B,C, and D fill with all SST cladding elements. For the cooling system every valve has been substituted with a new one. A new cooling system display has been assembled. Pressure and flux sensors have been placed on the primary circuit

  5. Operating experience from Swedish nuclear power plants 2003

    2004-01-01

    In safety terms, operations of the Swedish nuclear power plants in 2003 can be summarized as having ben good, with a few exceptions: The thermal mixer problem at Barsebaeck-2; The Highest Permissible Limit Value excursion at OKG-3, which subjected the reactor pressure vessel to a too rapid temperature change; and An INES class 1 incident at Ringhals-1. The Barsebaeck and Ringhals events were not of such seriousness as to represent a threat to reactor safety, but they both had the effect of causing the Nuclear Power Inspectorate to question safety cultures at the plants. The mixer event resulted in a considerable production loss, with the reactor being shut down twice, making a total of five months. OKG-3 was shut down for almost two months during the autumn. Despite the above, production from Swedish NPPs was much the same as during 2002. Total electricity production amounted to 65 TWh (65.2 TWh in 2002). On the average the energy availability of the eleven reactors was 79%. The PWRs at Ringhals had an average energy availability of 89%, while the BWRs reached 76%

  6. Operational experience with nanocoulomb bunch charges in the Cornell photoinjector

    Adam Bartnik

    2015-08-01

    Full Text Available Characterization of 9–9.5 MeV electron beams produced in the dc-gun based Cornell photoinjector is given for bunch charges ranging from 20 pC to 2 nC. Comparison of the measured emittances and longitudinal current profiles to optimized 3D space charge simulations yields excellent agreement for bunch charges up to 1 nC when the measured laser distribution is used to generate initial particle distributions in simulation. Analysis of the scaling of the measured emittance with bunch charge shows that the emittance scales roughly as the square root of the bunch charge up to 300 pC, above which the trend becomes linear. These measurements demonstrate that the Cornell photoinjector can produce cathode emittance dominated beams meeting the emittance and peak current specifications for next generation free electron lasers operating at high repetition rate. In addition, the 1 and 2 nC results are relevant to the electron ion collider community.

  7. Offshore wind farm Bockstigen - installation and operation experience

    Lange, B [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark); Aagaard, E; Andersen, P E; Moeller, A [Wind World af 1997 A/S, Noerresundby (Denmark); Niklasson, S; Wickman, A [Vindkompaniet, Degerhamn (Sweden)

    1999-03-01

    The first Swedish offshore wind farm Bockstigen is operating since March 1998 near the coast of Gotland. It was built as a demonstration project by the Swedish wind farm developer Vindkompaniet, the Danish wind turbine manufacturer Wind World and the British offshore construction company Seacore and partly funded under the EU-THERMIE program. Bockstigen is the fourth offshore wind farm world-wide. While at previous wind farms the main emphasis laid on the demonstration of the technical feasibility of offshore wind energy utilisation, Bockstigen was aimed at demonstrating its economic viability. A number of innovative concepts have been employed: Drilled monopile foundations were used to save costs. A new construction method has been applied making use of a jack-up barge. A new control system for the turbines and the whole wind farm was developed, which controls the maximum power output, the flicker and the reactive power consumption depending on online measurements of the actual grid state. These new developments have been implemented successfully. A substantial cost reduction compared to previous offshore projects could be achieved. (au)

  8. Operating experience review - Ventilation systems at Department of Energy Facilities

    1994-05-01

    The Office of Special Projects (DP-35), formerly Office of Self-Assessment (DP-9), analyzed occurrences caused by problems with equipment and material and recommended the following systems for an in-depth study: (1) Selective Alpha Air Monitor (SAAM), (2) Emergency Diesel Generator, (3) Ventilation System, (4) Fire Alarm System. Further, DP-35 conducted an in-depth review of the problems associated with SAAM and with diesel generators, and made several recommendations. This study focusses on ventilation system. The intent was to determine the causes for the events related to these system that were reported in the Occurrence Reporting and Processing System (ORPS), to identify components that failed, and to provide technical information from the commercial and nuclear industries on the design, operation, maintenance, and surveillance related to the system and its components. From these data, sites can develop a comprehensive program of maintenance management, including surveillance, to avoid similar occurrences, and to be in compliance with the following DOE orders.

  9. Operating experiences of reactor shutdown system at MAPS

    Kotteeswaran, T.J.; Subramani, V.A.; Hariharan, K.

    1997-01-01

    The reactors in Madras Atomic Power Station (MAPS), Kalpakkam are Pressurised Heavy Water Reactors (PHWR) similar to RAPS, Kota. The moderator heavy water is pumped into the calandria from dump tank to make the reactor critical. Later with the calandria level held constant at 92% FT, the further power changes are being done with the movement of adjuster rods. The moderator is held in calandria by means of helium gas pressure differential between top of calandria and dump tank located below. The shutdown of the reactor is effected by dumping the moderator water to dump tank by fast equalizing of helium gas pressure. In the revised mode of operation of moderator circuit after the moderator inlet manifold failure, the dump timing was observed to be more compared to the normal value. This was investigated and observed to be due to accumulation of D 2 O in the gas space above dump valves, which was affecting the helium equalizing flow. Also some of Indicating Alarm Meters (IAM) in protective system initiating the trip signals have failed in the unsafe mode. They have been modified to avoid the recurrence of the failures. (author)

  10. Operating experience from Swedish nuclear power plants, 2000

    2001-01-01

    From a safety point of view, 2000 was - as were previous years - satisfactory. Total electricity production from the Swedish nuclear power stations amounted to 54.2 TWh, which was over 20% less than the 70.2 TWh produced in 1999. The two main reasons for the reduction were the closure of Barsebaeck 1 on 1st December 1999, and the cutback in output from all reactors due to the particularly good availability of hydro power in 2000. Some reactors were even shut down completely as a result of the low power demand, which has not happened previously. The quantity of unutilised production capacity as a result of these reductions amounted to 11.6 TWh. Costdown operation prior to the annual overhaul shutdowns, which makes better use of the fuel, represented a further 2.1 TWh of unutilised capacity. The average energy availability of the three PWRs at Ringhals was 82.0%, while that of the eight BWRs was 84.2%. Forsmark 3, Ringhals 3 and Oskarshamn 3 all had average availabilities of over 90%. Of five events with safety implications that occurred in the plants during the year, three are described under Special Reporting. One of them relates to the crack indications in welds that were found in an American PWR in the autumn, and which were subsequently also found in Ringhals 4

  11. Operational experience and recent developments at the National Medical Cyclotron

    Conard, E.; Pac, B.; Arnott, D.W.

    1994-01-01

    The National Medical Cyclotron is a radioisotope production facility run by ANSTO and located on the grounds of the Royal Prince Alfred Hospital in Sydney, Australia. A CYCLONE 30 (IBA) cyclotron is used in the production of short-lived PET radiopharmaceuticals required by the hospital's PET Scanner and also to produce a number of bulk radiochemicals for processing and distribution throughout Australasia. Following commissioning of the cyclotron and beam lines in October 1991, and the overcoming of a number of early open-quote teething close-quote problems especially relating to the reliability of the r.f. and solid target transport systems, a steady program of improvements has been pursued. These improvements have included development of new beam diagnostics and the design and installation of a new beam line for SPECT radioisotope production. The current operations schedule includes the production of 18 FDG, 13 NH 3 , 15 O 2 and 201 Tl, 67 Ga and 123 I. This paper will discuss the process of development of the cyclotron to ably meet the present demands on it, and the problems resolved in the pursuit of this goal

  12. Hanaro operation

    Lee, Ji Bok; Jeon, Byung Jin; Kwack, Byung Ho

    1997-01-01

    HANARO was configurated its first operating core in 1995. Long term operation test was conducted up to 3-1 cycle during 1996, in order to investigate the reactor characteristics due to fuel depletion and additional fuel loading. Now HANARO has accumulated 168.4 days of total operation time and 2,687.5 MWD of total thermal output. Reactor analysis, producing operation datum and its validation with test, periodic inspection and maintenance of the facility are continuously conducted for safe operation of the HANARO. Conducted the verification tests for installed utilization facilities, and successfully performed the radiation emergency drill. The shutdown report of TRIGA Mark II and III was submitted to MOST, and decommissioning will be started from 1997. (author). 70 tabs., 50 figs., 27 refs

  13. Operation experiences of the JT-60 first walls during high-power additional heating experiments

    Takatsu, H.; Ando, T.; Yamamoto, M.; Arai, T.; Kodama, K.; Suzuki, M.; Shimizu, M.

    1989-01-01

    JT-60 started its operation in May 1985 with TiC-coated molybdenum or Inconel 625 first walls. They provided very clean surfaces as well as superior plasma characteristics during Joule heating discharges. Though 20 μm-thick TiC coatings showed good adhesion characteristics, melting of the TiC coating and also the molybdenum or Inconel 625 substrate was observed at some specific spots, and an influx of heavy metals to the main plasma was inevitable during discharges. Initial results of the additional heating experiments showed degrading effects of locally melted TiC-coated molybdenum or Inconel 625 on plasma operation. Therefore, about a half of the TiC-coated first walls were removed and new graphite first walls were installed during the venting period from April to May 1987. The start-up of the discharge conditioning after installation of a significant number of graphite tiles was very rapid. Flexibility in plasma operation was increased, and JT-60 extended the operation region beyond its original specifications. The graphite first walls of the main chamber performed admirably and maintained their integrity under the conditions of plasma current and additional heating power up to 3.2 MA and 30 MW, respectively. On the other hand, the number of damaged divertor plates was much larger than that expected. The reason of unexpected failure is now under examination. (orig.)

  14. Experiment operations plan for the MT-4 experiment in the NRU reactor

    Russcher, G.E.; Wilson, C.L.; Parchen, L.J.; Marshall, R.K.; Hesson, G.M.; Webb, B.J.; Freshley, M.D.

    1983-06-01

    A series of thermal-hydraulic and cladding materials deformation experiments were conducted using light-water reactor fuel bundles as part of the Pacific Northwest Laboratory Loss-of-Coolant Accident (LOCA) Simulation Program. This report is the formal operations plan for MT-4 - the fourth materials deformation experiment conducted in the National Research Universal (NRU) reactor, Chalk River, Ontario, Canada. A major objective of MT-4 was to simulate a pressurized water reactor LOCA that could induce fuel rod cladding deformation and rupture due to a short-term adiabatic transient and a peak fuel cladding temperature of 1200K (1700 0 F)

  15. Improving the Sharing and Use of Operating Experience Among Pressurized Heavy Water Reactors

    Llewellyn, Michael D.

    1998-01-01

    Effective use of operating experience is an essential and fundamental aspect of the business of improving safety and reliability of nuclear power plant. Operating experience is considered of such importance, that it is embedded as a fundamental element in the WANO mission statement: 'To maximise the safety and reliability of operation of nuclear power plants by exchanging information and encouraging communication, comparison, and emulation amongst its members'. The exchange of information on plant operating experience and lessons learned from events is at the core of our WANO mission and is an essential element of effective operating experience use. Recognizing this, WANO - AC has joined together with Canadian PHWR operators in a cooperative effort to further strengthen the sharing of the event information, and to facilitate communication of PHWR operating experience worldwide. The content of the paper is: 1. Discussion; 2. Expectation; 3. Improving use of operating experience; 4. Internalizing operating experience; 5. Summary; 6. Attachments. The three attachments deal with: - WANO event reporting guidelines; - Root cause investigation guidelines; - Example prevent events briefing sheet. The paper is completed with the five slides used in the oral presentation

  16. The Ricor K508 cryocooler operational experience on Mars

    Johnson, Dean L.; Lysek, Mark J.; Morookian, John Michael

    2014-01-01

    The Mars Science Laboratory (Curiosity) landed successfully on Mars on August 5, 2012, eight months after launch. The chosen landing site of Gale Crater, located at 4.5 degrees south latitude, 137.4 degrees east longitude, has provided a much more benign environment than was originally planned for during the critical design and integration phases of the MSL Project when all possible landing sites were still being considered. The expected near-surface atmospheric temperatures at the Gale Crater landing site during Curiosity's primary mission (1 Martian year or 687 Earth days) are from −90°C to 0°C. However, enclosed within Curiosity's thermal control fluid loops the Chemistry and Mineralogy (CheMin) instrument is maintained at approximately +20°C. The CheMin instrument uses X-ray diffraction spectroscopy to make precise measurements of mineral constituents of Mars rocks and soil. The instrument incorporated the commercially available Ricor K508 Stirling cycle cryocooler to cool the CCD detector. After several months of brushing itself off, stretching and testing out its subsystems, Curiosity began the exploration of the Mars surface in October 2012. The CheMin instrument on the Mars Science Laboratory (MSL) received its first soil sample from Curiosity on October 24, and successfully analyzed its first soil sample. After a brief review of the rigorous Ricor K508 cooler qualification tests and life tests based on the original MSL environmental requirements this paper presents final pre-launch instrument integration and testing results, and details the operational data of the CheMin cryocooler, providing a snapshot of the resulting CheMin instrument analytical data

  17. The Ricor K508 cryocooler operational experience on Mars

    Johnson, Dean L.; Lysek, Mark J.; Morookian, John Michael [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2014-01-29

    The Mars Science Laboratory (Curiosity) landed successfully on Mars on August 5, 2012, eight months after launch. The chosen landing site of Gale Crater, located at 4.5 degrees south latitude, 137.4 degrees east longitude, has provided a much more benign environment than was originally planned for during the critical design and integration phases of the MSL Project when all possible landing sites were still being considered. The expected near-surface atmospheric temperatures at the Gale Crater landing site during Curiosity's primary mission (1 Martian year or 687 Earth days) are from −90°C to 0°C. However, enclosed within Curiosity's thermal control fluid loops the Chemistry and Mineralogy (CheMin) instrument is maintained at approximately +20°C. The CheMin instrument uses X-ray diffraction spectroscopy to make precise measurements of mineral constituents of Mars rocks and soil. The instrument incorporated the commercially available Ricor K508 Stirling cycle cryocooler to cool the CCD detector. After several months of brushing itself off, stretching and testing out its subsystems, Curiosity began the exploration of the Mars surface in October 2012. The CheMin instrument on the Mars Science Laboratory (MSL) received its first soil sample from Curiosity on October 24, and successfully analyzed its first soil sample. After a brief review of the rigorous Ricor K508 cooler qualification tests and life tests based on the original MSL environmental requirements this paper presents final pre-launch instrument integration and testing results, and details the operational data of the CheMin cryocooler, providing a snapshot of the resulting CheMin instrument analytical data.

  18. Summary of operating experience in Swedish nuclear power plants 1994

    1995-01-01

    1994 was a record year for nuclear power in Sweden. For the second time, electricity generation from nuclear power exceeded 70 TWh (billions of kilowatt hours). Nuclear electricity generation corresponded to 51% of the total electricity generated in Sweden. Four units had an energy availability of more than 90%, while another five units had an availability of between 84 and 90%. This can be compared with an average international availability of 75%. Barsebaeck 2 was shut down during January to complete measures to correct a leak which was detected in the containment embedded steel plating in autumn 1993. During the year, a number of events occurred at Barsebaeck which were mainly caused by human error. A special evaluation of plant activities showed that the events occurred in connection with a reorganization which had been carried out. At year-end, it was discovered that the main steam line safety relief valves in Ringhals 2 were not correctly calibrated. The cause of the error was established and corrected and the safety relief valves at the other Ringhals PWRs were checked. Oskarshamn 1 was shut down for the whole year for a further inspection and modernization program. Manual inspections of the lower plenum of the reactor vessel were carried out for the first time ever in the world. The work methods, which have attracted considerable international interest, open up completely new dimensions for the maintenance and repair of reactor pressure vessels. The radiation doses to the personnel, which during 1993 were higher than usual, showed a marked decline in 1994. At the end of 1994, all of the Swedish nuclear power plants, apart from Oskarshamn 1, were in operation

  19. Experience in construction and operation of HWR plants in Argentina

    Madero, C.C.; Cosentino, J.O.

    1982-01-01

    ''ATUCHA I'', the first nuclear power plant in Argentina, is in commerical operation since 1974 with a high capacity factor. The reactor is based on the MZFR prototype designed by SIEMENS with natural uranium and heavy water and PWR technic. The plant was built by SIEMENS on a turnkey contract and was rated 340 MWe. The offer presented in that opportunity by KWU was based on two reactors (ATUCHA I type) inside one single containment, due to the limitation in power of the reactor. Subsequent changes in the nature of the contract resulted in an active participation of CNEA engineering groups in the erection and commissioning of the reactor. In 1978 the national government approved a nuclear power plan to install four 600 MWe HWR plants until 1995. To start implementing this program, CNEA called for tenders for the supply of components and services for the ATUCHA II plant, in connection with the establishment of a local engineering company and the supply and construction of a heavy water production plant. In 1980 a contract was signed with KWU and the local company ENACE was formed to act as architect engineer and site coordinator. The plant will be located in the ATUCHA I site and the reactor will be similar but double in power to that one. Following the schedule of the nuclear plan, CNEA has just started preliminary studies for the next nuclear plant. ENACE will be responsible for the preparation of an offer for an ATUCHA reactor type. Local engineering and manufacturing firms, upon request and coordination from CNEA, and evaluating the local capacity to participate in the design and construction of a CANDU type nuclear plant. Final decision on this fourth nuclear plant in Argentina will be taken middle 1983. (J.P.N.)

  20. Operational experience with a high speed video data acquisition system in Fermilab experiment E-687

    Baumbaugh, A.E.; Knickerbocker, K.L.; Baumbaugh, B.; Ruchti, R.

    1987-01-01

    Operation of a high speed, triggerable, Video Data Acquisition System (VDAS) including a hardware data compactor and a 16 megabyte First-In-First-Out buffer memory (FIFO) will be discussed. Active target imaging techniques for High Energy Physics are described and preliminary experimental data is reported.. The hardware architecture for the imaging system and experiment will be discussed as well as other applications for the imaging system. Data rates for the compactor is over 30 megabytes/sec and the FIFO has been run at 100 megabytes/sec. The system can be operated at standard video rates or at any rate up to 30 million pixels/second. 7 refs., 3 figs