WorldWideScience

Sample records for years operational experience

  1. EBR-II: twenty years of operating experience

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  3. HANARO operation experience in the year 2004

    International Nuclear Information System (INIS)

    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)

  4. CANDU operating experience

    International Nuclear Information System (INIS)

    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)

  5. The experience of five years operation of Phenix

    International Nuclear Information System (INIS)

    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)

  6. The safeguards on-site laboratory at Sellafield. Five years operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Duinslaeger, L.; Belle, P. van; Mayer, K.; Casteleyn, K.; Abousahl, S.; Daures, P.; Eberle, H.; Enright, T.; Guiot, A.; Hild, M.; Horta Domenech, J.; Lajarge, P.; Laurent, P.; Le Terrier, A.; Lynch, B.; Marucci, M.; Millet, S.; Ottmar, H.; Richir, P.; Street, S.; Vallet, P.; Zuleger, E. [European Commission, Karlsruhe (Germany). Inst. for Transuranium Elements

    2004-06-01

    The start of operation of the large reprocessing facilities led Euratom Safeguards to a new approach for verification analysis of samples taken at the facility: the installation of on-site laboratories. The availability of analytical capabilities for independent verification measurements at the site of these facilities offers obvious advantages in view of timeliness of results. The 'On-Site Laboratory' (OSL) at the BNFL Sellafield site was the first ever and entered into operation in 1999. For almost five years, the Institute for Transuranium Elements (ITU) has been operating the laboratory under routine conditions. During this period, more than one thousand safeguards samples were analysed. The experience gained in the management, logistics and operation of the OSL allow a critical review based on a significant period in time. This includes also aspects of training of staff, maintenance of equipment, flow of information, and improvements in the efficiency. The analytical issues are of key importance: based on the operational experience, the measurement methods were adapted (changing boundary conditions), the distribution of samples according to material type changed (start up of MOS fabrication plant), and the cutback in resources triggered a further streamlining of the analytical efforts. (orig.)

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

    International Nuclear Information System (INIS)

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Pioneering superconducting magnets in large tokamaks: evaluation after 16 years of operating experience in tore supra

    International Nuclear Information System (INIS)

    Duchateau, J.L.; Gravil, B.; Tena, E.; Henry, D.; Journeaux, J.Y.; Libeyre, P.

    2004-01-01

    The toroidal field (TF) system of Tore Supra (TS) is superconducting. After 16 years of operation it is possible to give an overview of the experience gained on a large superconducting system integrated in a large Tokamak. Quantitative data will be given, about the TF system for the cryogenic system and for the magnet system as well, concerning the number of plasmas shots and the availability of the machine. The origin and the number of breakdowns or incidents will be described, with emphasis on cryogenics, to document repairs and changes on the system components. Concerning the behaviour during operation, the Fast Safety Discharges (FSD) in operation are of particular interest for the Tokamak operation, as they interrupt it on a significant time of the order of one hour. This aspect is particularly documented. The approach followed to decrease the number of these FSD will be reported and explained. The Tore Supra Tokamak was the first important meeting between Superconductivity and Plasma Physics on a large scale. Overall, despite the differences in design and size, the accumulated experience over 16 years of operation is a useful tool to prepare the manufacturing and the operation of the ITER magnets. (authors)

  10. Five years of operating experience with Phenix

    International Nuclear Information System (INIS)

    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

  11. Pioneering superconducting magnets in large tokamaks: Evaluation after 16 years of operating experience in tore supra

    International Nuclear Information System (INIS)

    Libeyre, P.; Duchateau, J.L.; Gravil, B.; Tena, E.; Henry, D.; Journeaux, J.Y.

    2005-01-01

    The toroidal field (TF) system of TORE SUPRA (TS) is superconducting. After 16 years of operation it is possible to give an overview of the experience gained on a large superconducting system integrated in a large Tokamak. Quantitative data will be given, about the TF system for the cryogenic system and for the magnet system as well, concerning the number of plasmas shots and the availability of the machine. The origin and the number of breakdowns or incidents will be described, with emphasis on cryogenics and associated repairs and changes on the system components along the time. As concerns the behaviour during operation, the fast safety discharges (FSD) in operation are of particular interest for the Tokamak operation, as they interrupt it for a significant time of the order of 1 h. This aspect is particularly documented. The approach followed to decrease the number of these FSD will be reported and explained. The TORE SUPRA Tokamak was the first important application of superconductivity in plasma physics on a large scale. Overall, despite the differences in design and size, the accumulated experience over 16 years of operation is a useful tool to prepare the manufacture and the operation of the ITER magnets

  12. The LHC cryogenic system and operational experience from the first three years run

    International Nuclear Information System (INIS)

    Delikaris, Dimitri; Tavian, Laurent

    2014-01-01

    The LHC (Large Hadron Collider) accelerator helium cryogenic system consists of eight cryogenically independent sectors, each 3.3 km long, all cooled and operated at 1.9 K. The overall, entropy equivalent, installed cryogenic capacity totalizes 144 kW (a) 4.5 K including 19.2 kW (a) 1.8 K with an associated helium inventory of 130 ton. The LHC cryogenic system is considered among the most complex and powerful in the world allowing the cooling down to superfluid helium temperature of 1.9 K. of the accelerators' high field superconducting magnets distributed over the 26.7 km underground ring. The present article describes the LHC cryogenic system and its associated cryogen infrastructure. Operational experience, including cryogen management, acquired from the first three years of LHC operation is finally presented. (author)

  13. Microwave tokamak experiment (MTX) first year of operation and future plans

    International Nuclear Information System (INIS)

    Jackson, M.C.

    1989-01-01

    The Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) began plasma operations in November 1988, and our main goal is the study of electron-cyclotron heating (ECH) in plasma discharges. The MTX tokamak was relocated from the Massachusetts Institute of Technology (MIT), and we have re-created plasma parameters that are similar to those generated while the tokamak was at MIT. After stable ohmic operation was achieved, single-pulse FEL heating experiments began. During this phase, the FEL operated at low power levels on the way to its ultimate goal of 2 GW and 140 GHz with a 30-ns pulse length. We have developed a number of new diagnostics to measure these fast FEL pulses and the resulting plasma effects. In this paper, we present results that show the correlation of MTX data with MIT data, some of the operational modifications and procedures used, results to date from preliminary tokamak operations with the FEL, and our near-term operational plans. 7 refs., 8 figs., 1 tab

  14. Operating experience in reprocessing

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  16. ERB-II operating experience

    International Nuclear Information System (INIS)

    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

  17. Combining risk analysis and operating experience

    International Nuclear Information System (INIS)

    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. Operating experience with snubbers

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  20. Recent operating experiences and programs at EBR-II

    International Nuclear Information System (INIS)

    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

  1. Building and Deploying Remotely Operated Vehicles in the First-Year Experience

    Science.gov (United States)

    O'Brien-Gayes, A.; Fuss, K.; Gayes, P.

    2007-12-01

    Coastal Carolina University has committed to improving student retention and success in Mathematics and Science through a pilot program to engage first-year students in an applied and investigative project as part of the University's First-Year Experience (FYE). During the fall 2007 semester, five pilot sections of FYE classes, consisting of students from the College of Natural and Applied Sciences are building and deploying Remotely Operated Vehicles (ROVs). These ROV-based classes are designed to: accelerate exploration of the broad fields of science and mathematics; enlist interest in technology by engaging students in a multi-stepped, interdisciplinary problem solving experience; explore science and mathematical concepts; institute experiential learning; and build a culture of active learners to benefit student success across traditional departmental boundaries. Teams of three students (forty teams total) will build, based on the MIT Sea Perch design, and test ROVs in addition to collecting data with their ROVs. Various accessories attached to the vehicles for data collection will include temperature and light sensors, plankton nets and underwater cameras. The first-year students will then analyze the data, and the results will be documented as part of their capstone projects. Additionally, two launch days will take place on two campus ponds. Local middle and high school teachers and their students will be invited to observe this event. The teams of students with the most capable and successful ROVs will participate in a workshop held in November 2007 for regional elementary, middle and high school teachers. These students will give a presentation on the building of the ROVs and also provide a hands-on demonstration for the workshop participants. These activities will ensure an incorporation of service learning into the first semester of the freshmen experience. The desired outcomes of the ROV-based FYE classes are: increased retention at the postsecondary

  2. Kayenta advanced series compensation operational experience

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. PUSPATI Triga Reactor - First year in operation

    International Nuclear Information System (INIS)

    Nahrul Khair Rashid.

    1983-01-01

    First year operation of RTP reactor was mostly devoted to making in house training, setting up and testing the facilities in preparation for more routine operations. Generally the operations are categorized into 4 main purposes; experiment of research, teaching and training, demonstration, and testing and maintenance. These four purposes are elaborated in detail. Additions and modifications were performed in order to improve the safety of reactor operation. (A.J.)

  4. GE-Hitachi ABWR Design for 60 Years of Operation

    International Nuclear Information System (INIS)

    Hoang Xuan Hoa

    2011-01-01

    The GE Hitachi ABWR design benefits from the experiences of the prior generation BWRs in operation since the 1970s, and the knowledge learned from years of technical research on the aging effects on reactor systems, structures and components. The impact of exposure to neutrons over time to the reactor pressure vessel and internal components was evaluated to confirm their structural integrity. Other time-based plant analyses, such as fatigue vibration and corrosion effect, have also been performed on the ABWR to support a 60-year plant life assumption. Finally, operating experience and aging lessons learned have been used to verify the maintenance plans for plant aging management are acceptable to support operation up to 60 years. (author)

  5. The general surgery chief resident operative experience: 23 years of national ACGME case logs.

    Science.gov (United States)

    Drake, Frederick Thurston; Horvath, Karen D; Goldin, Adam B; Gow, Kenneth W

    2013-09-01

    The chief resident (CR) year is a pivotal experience in surgical training. Changes in case volume and diversity may impact the educational quality of this important year. To evaluate changes in operative experience for general surgery CRs. Review of Accreditation Council for Graduate Medical Education case logs from 1989-1990 through 2011-2012 divided into 5 periods. Graduates in period 3 were the last to train with unrestricted work hours; those in period 4 were part of a transition period and trained under both systems; and those in period 5 trained fully under the 80-hour work week. Diversity of cases was assessed based on Accreditation Council for Graduate Medical Education defined categories. Total cases and defined categories were evaluated for changes over time. The average total CR case numbers have fallen (271 in period 1 vs 242 in period 5, P surgery training may be jeopardized by reduced case diversity. Chief resident cases are crucial in surgical training and educators should consider these findings as surgical training evolves.

  6. Steam generator operating experience update, 1982-1983

    International Nuclear Information System (INIS)

    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

  7. Operational strategy, economic and environmental performance of sludge treatment reed bed systems - based on 28 years of experience

    DEFF Research Database (Denmark)

    Nielsen, S.; Larsen, Julie Dam

    2016-01-01

    Sludge treatment reed bed (STRB) systems have been used for dewatering and mineralisation of sludge in Europe since 1988. STRB systems provide substantial environmental, economic, and operational benefits compared to mechanical sludge dewatering solutions such as belt presses and centrifuges....... They require less energy, no chemicals, reduce the sludge volume and produce bio solids with dry solid contents up to 20-40% under Danish climate conditions, depending on the sludge quality. Experience has shown that sludge treated in STRBs represents a high quality product with a low content of pathogens...... compared to conventional mechanical dewatering devices, delivering an economic break-even of about 3-5 years. This paper provides an overview of the operation and maintenance costs and environmental benefits of a typical STRB based on the experiences gained from the operation of a large number of STRBs...

  8. Operational experience of the Marcoule reactors

    International Nuclear Information System (INIS)

    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. Operating experience with high beta superconducting RF cavities

    International Nuclear Information System (INIS)

    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

  10. Operating experience with high beta superconducting rf cavities

    International Nuclear Information System (INIS)

    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

  11. Two-year experience of the Loviisa-1 nuclear power plant operation in Finland

    International Nuclear Information System (INIS)

    Palmgren, A.; Simola, P.; Skyutta, P.; Malkov, Yu.V.; Mal'tsev, B.K.; Shasharin, G.A.

    1979-01-01

    The description of experience of creation and operation of the Loviisa-1 nuclear power plant in Finland is presented. The main stages of power block development were the following: functional tests of systems and equipment, hydraulic tests of the reactor and primary circuit, inspection of equipment, hot testing, testing of protective envelope, second inspection, reactor assembling and fuel loading, physical and power start-up of the reactor, testing of the plant as a whole. Tests of the APP operation on load were particularly extensive. These tests were carried out on the 5, 15, 30, 50, 75 and 92 % thermal power levels of the reactor and covered: physical reactor tests, electric and dynamic tests of the power unit, tests with failures in equipment operation, chemical tests, studies of shielding effectiveness, thermal and guarantee tests. The positive experience of the Loviisa-1 nuclear power plant operation, reactor reliability, fuel element tightness, high efficiency (33.9 %) and satisfactory operation of turbo-generator confirm the success of the Loviisa-1 NPP project

  12. Operator training and the training simulator experience

    International Nuclear Information System (INIS)

    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

  13. 20 years' operation of the Rheinsberg nuclear power plant

    International Nuclear Information System (INIS)

    Lehmann, R.; Quasniczka, H.; Fiss, W.; Hentschel, G.; Schulz, K.D.

    1986-01-01

    After a 20 years' operation of the Rheinsberg nuclear power plant a review of the operating results achieved, performance of the main equipment, research and development works performed, and experience gained with education and training of plant staff is given. (author)

  14. Slaughterhouse waste co-digestion - Experiences from 15 years of full-scale operation

    OpenAIRE

    Ek, Anders; Hallin, Sara; Vallin, Lina; Schnurer, Anna; Karlsson, Martin

    2011-01-01

    At Tekniska Verken in Linköping AB (TVAB) there is a long time experience of handling and producing biogas from large volumes of slaughterhouse waste. Experiences from research and development and plant operations have lead to the implementation of several process improving technological/biological solutions. We can in this paper describe how the improvements have had several positive effects on the process, including energy savings, better odor control, higher gas quality, increased organic ...

  15. Thirty year operational experience of the JET flywheel generators

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Operating experience with the DRAGON High Temperature Reactor experiment

    International Nuclear Information System (INIS)

    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)

  17. Operating experience feedback

    International Nuclear Information System (INIS)

    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)

  18. Continuous Air Monitor Operating Experience Review

    International Nuclear Information System (INIS)

    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

  19. Operating Experience at NPP Krsko

    International Nuclear Information System (INIS)

    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)

  20. Eight years' operation of the SGHWR prototype

    International Nuclear Information System (INIS)

    Phillips, J.L.

    1976-01-01

    Experience gained of the SGHWR system during the first eight years of operation of the UKAEA's 100 MW(e) prototype at AEE Winfrith is discussed. Modifications and additions have been made to the plant to overcome problems which only operation of a prototype unit can reveal. No problems have arisen which could not be overcome by the application of normal engineering resources, and there is no reason why the commercial successor to the prototype should be other than a fully viable proposition. (author)

  1. The SM and MIR reactors operation experience

    International Nuclear Information System (INIS)

    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.)

  2. Operating manual for the critical experiments facility

    International Nuclear Information System (INIS)

    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

  3. Operating manual for the critical experiments facility

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. ETSON proposal on the European operational experience feedback system

    International Nuclear Information System (INIS)

    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

  5. Operational experience with Dragon reactor experiment of relevance to commercial reactors

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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. Ten years's reactor operation at the Technical University Zittau - operation report

    International Nuclear Information System (INIS)

    Konschak, K.

    1990-01-01

    The Zittau Training and Research Reactor ZLFR is in use for purposes of teaching the engineers who will operate the nuclear power plants in the GDR since 10 years. Since commissioning it was started up more than 1600 times, approximately two thirds of the start-ups being utilized for purposes of teaching. A number of teaching experiments were installed that demonstrate fundamental technological processes in nuclear reactors in a manner easy to understand. The high level of nuclear safety manifests itself, among other things, in extremely low radiation exposures of the operating personal and the persons to be trained. (author)

  8. Three years operational experience with biodiesel

    International Nuclear Information System (INIS)

    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. Operation experience at the UWTF

    International Nuclear Information System (INIS)

    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)

  10. Non-operative management of blunt splenic injuries in a paediatric population: a 12-year experience.

    Science.gov (United States)

    Kirkegård, Jakob; Avlund, Tue Højslev; Amanavicius, Nerijus; Mortensen, Frank Viborg; Kissmeyer-Nielsen, Peter

    2015-02-01

    Non-operative management (NOM) is now the primary treatment for blunt splenic injuries in children. Only one study has examined the use of NOM in a Scandinavian population. Thus, the purpose of this study is to report our experience in treating children with blunt splenic injuries with NOM at a Danish university hospital. We conducted a retrospective observational study of 34 consecutive children (aged 16 years or less) admitted to our level 1-trauma centre with blunt splenic injury in the 12-year period from 1 January 2001 to 31 December 2012. Data on patients and procedures were obtained by review of all medical records and re-evaluation of all initial computed tomographies (CT). We included 34 children with a median age of 10.5 years (67.6% males) in this study. All patients were scheduled for NOM, and two (5.9%) patients underwent splenic artery embolisation (SAE). Two (5.9%) patients later needed surgical intervention. The NOM success rate was 88% (95% confidence interval (CI): 73-97%) without SAE and 94% (95% CI: 80-99%) with SAE. We found no difference in the American Association for the Surgery of Trauma grade when comparing the initial CT evaluation (mean 2.59 ± 1.1) with the CT re-evaluation (mean 2.71 ± 0.94); p = 0.226. We demonstrated a high degree of success and safety of non-operative treatment in children with blunt splenic injury in a Scandinavian setting. Our results are comparable to international findings.

  11. Undergraduate surgical nursing preparation and guided operating room experience: A quantitative analysis.

    Science.gov (United States)

    Foran, Paula

    2016-01-01

    The aim of this research was to determine if guided operating theatre experience in the undergraduate nursing curricula enhanced surgical knowledge and understanding of nursing care provided outside this specialist area in the pre- and post-operative surgical wards. Using quantitative analyses, undergraduate nurses were knowledge tested on areas of pre- and post-operative surgical nursing in their final semester of study. As much learning occurs in nurses' first year of practice, participants were re-tested again after their Graduate Nurse Program/Preceptorship year. Participants' results were compared to the model of operating room education they had participated in to determine if there was a relationship between the type of theatre education they experienced (if any) and their knowledge of surgical ward nursing. Findings revealed undergraduates nurses receiving guided operating theatre experience had a 76% pass rate compared to 56% with non-guided or no experience (p nurses achieved a 100% pass rate compared to 53% with non-guided or no experience (p research informs us that undergraduate nurses achieve greater learning about surgical ward nursing via guided operating room experience as opposed to surgical ward nursing experience alone. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  14. Recent U.S. reactor operating experience

    International Nuclear Information System (INIS)

    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

  15. Stack Monitor Operating Experience Review

    International Nuclear Information System (INIS)

    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.

  16. Operating experience feedback in TVO

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Nuclear units operating improvement by using operating experience

    International Nuclear Information System (INIS)

    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)

  18. Operating experience with gamma ray irradiators

    International Nuclear Information System (INIS)

    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

  19. Slaughterhouse waste co-digestion - Experiences from 15 years of full-scale operation

    Energy Technology Data Exchange (ETDEWEB)

    Ek, A.E.W. (Swedish Biogas International Korea Co., Ltd, Totaleco B/D 1302-7, Seocho-Dong, Seocho-Gu, Seoul (Korea, Republic of)); Hallin, S.; Vallin, L. (Dept. of Biogas R and D, Tekniska Verken i Linkoeping AB (Sweden)); Schnurer, A. (Dept. of Microbiology, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Karlsson, M. (Dept. of Biogas R and D, Tekniska Verken i Linkoeping AB (Sweden); Dept. of Physics, Chemistry and Biology, Linkoeping Univ., Linkoeping (Sweden)), E-mail: martin.karlsson@tekniskaverken.se

    2012-01-15

    At Tekniska Verken in Linkoeping AB (TVAB) there is a long time experience of handling and producing biogas from large volumes of slaughterhouse waste. Experiences from research and development and plant operations have lead to the implementation of several process improving technological/biological solutions. We can in this paper describe how the improvements have had several positive effects on the process, including energy savings, better odor control, higher gas quality, increased organic loading rates and higher biogas production with maintained process stability. In addition, it is described how much of the process stability in anaerobic digestion of slaughter house waste relates to the plant operation, which allow the microbiological consortia to adapt to the substrate. Since digestion of proteinaceous substrates like slaughterhouse waste lead to high ammonia loads, special requirements in ammonia tolerance are placed on the microbiota of the anaerobic digestion. Biochemical assays revealed that the main route for methane production proceed through syntrophic acetate oxidation, which require longer retention times than methane production by acetoclastic methanogens. Thus, the long retention time of the plant, accomplished by a low dilution of the substrate, is a vital component of the process stability when treating high protein substrates like slaughterhouse waste

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Results from the S-DALINAC: one year of operational experience from a superconducting electron accelerator

    International Nuclear Information System (INIS)

    Graef, H.D.; Horn, J.; Hummel, K.D.; Luettge, C.; Richter, A.; Riedorf, T.; Ruehl, K.; Schardt, P.; Spamer, E.; Stiller, A.; Thomas, F.; Titze, O.; Toepper, J.; Weise, H.; Winkler, T.

    1992-01-01

    Since August 1991 the superconducting cw-electron accelerator S-DALINAC at Darmstadt has produced single and multi pass beam which is used for different experiments. At energies below 10 MeV investigations of channeling radiation production and nuclear resonance fluorescence experiments are performed. Single pass operation yielding beam energies up to 40 MeV has been used for tests of the Free Electron Laser (FEL) beamline and for the investigation of spontaneous emission from the undulator. Two and three pass operation at higher energies produces beam for electron scattering experiments,(e,e') and (e,e'x), as well as for the production of channeling radiation. True cw operation allows for energies up to 84 MeV limited by the capacity of the He refrigerator. At higher energies the duty factor has to be reduced and pulse length is on the order of seconds. The successful operation of the entire accelerator was the result of several developments: six accelerating cavities fabricated from RRR = 280 niobium raised the average field gradient to 6 MV/m; the control systems for gun, rf, cavity tuners, and the beam transport system including beam diagnostics have been integrated into a reliable remote control of the S-DALINAC; and computer controlled path length adjustments for the two recirculating beamlines were installed for optimization of the reinjection phase. (Author) fig., tab., 10 refs

  2. Regulatory challenges in using nuclear operating experience

    International Nuclear Information System (INIS)

    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)

  3. Resident operative experience in general surgery, plastic surgery, and urology 5 years after implementation of the ACGME duty hour policy.

    Science.gov (United States)

    Simien, Christopher; Holt, Kathleen D; Richter, Thomas H; Whalen, Thomas V; Coburn, Michael; Havlik, Robert J; Miller, Rebecca S

    2010-08-01

    Resident duty hour restrictions were implemented in 2002-2003. This study examines changes in resident surgical experience since these restrictions were put into place. Operative log data for 3 specialties were examined: general surgery, urology, and plastic surgery. The academic year immediately preceding the duty hour restrictions, 2002-2003, was used as a baseline for comparison to subsequent academic years. Operative log data for graduating residents through 2007-2008 were the primary focus of the analysis. Examination of associated variables that may moderate the relationship between fewer duty hours and surgical volume was also included. Plastic surgery showed no changes in operative volume following duty hour restrictions. Operative volume increased in urology programs. General surgery showed a decrease in volume in some operative categories but an increase in others. Specifically the procedures in vascular, plastic, and thoracic areas showed a consistent decrease. There was no increase in the percentage of programs' graduates falling below minimum requirements. Procedures in pancreas, endocrine, and laparoscopic areas demonstrated an increase in volume. Graduates in larger surgical programs performed fewer procedures than graduates in smaller programs; this was not the case for urology or plastic surgery programs. The reduction of duty hours has not resulted in an across the board decrease in operative volume. Factors other than duty hour reforms may be responsible for some of the observed findings.

  4. Tore Supra: technical aspects and early results after one year of operation

    International Nuclear Information System (INIS)

    Gravier, R.

    1989-01-01

    After one year operation (1988 to 1989), technical aspects of component systems and equipment of Tore Supra are summarized. Particular attention is given to the operation with: supraconducting toroidal field coil system, cryogenic system, poloidal field system, in vessel equipment, first wall conditioning, pump limiter. The ergodic divertor experiments and the current drive experiment are reported. The plasma heating methods adopted in Tore Supra are presented

  5. Operation and maintenance experience at the General Atomic Company's TRIGA reactor facility at San Diego, California

    International Nuclear Information System (INIS)

    Whittemore, W.L.; Stout, W.A.; Shoptaugh, J.R.; Chesworth, R.H.

    1982-01-01

    Since the startup of the original 250 kW TRIGA Mark I reactor in 1958, General Atomic Company has accumulated nearly 24 years of operation and maintenance experience with this type of reactor. In addition to the nearly 24 years of experience gained on the Mark I, GA has operated the 1.5 MW Advanced Prototype Test Reactor (Mark F) for 22 years and operated a 2 MW below-ground TRIGA Mark III for five years. Information obtained from normal and abnormal operation are presented. (author)

  6. Recent operating experiences with steam generators in Japanese NPPs

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  9. Technical report on operating experience with boiling water reactor offgas systems

    International Nuclear Information System (INIS)

    Lo, R.; Barrett, L.; Grimes, B.; Eisenhut, D.

    1978-03-01

    Over 100 reactor years of Boiling Water Reactor (BWR) operating experience have been accumulated since the first commercial operation of BWRs. A number of incidents have occurred involving the ''offgas'' of these Boiling Water Reactors. This report describes the generation and processing of ''offgas'' in Boiling Water Reactors, the safety considerations regarding systems processing the ''offgas'', operating experience involving ignitions or explosions of ''offgas'' and possible measures to reduce the likelihood of future ignitions or explosions and to mitigate the consequences of such incidents should they occur

  10. Lesson Learned from the Recent Operating Experience of Domestic Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lee, Chang-Ju; Kim, Min-Chull; Koo, Bon-Hyun; Kim, Sang-Jae; Lee, Kyung-Won; Kim, Ji-Tae; Lee, Durk-Hun

    2007-01-01

    According to the public concerns, it seems that one of the main missions of a nuclear regulatory body is to collect operational experiences from various nuclear facilities, and to analyze their follow-up information. The extensive use of lessons learned from operating experiences to back fit safety systems, improve operator training and emergency procedures, and to focus more attention on human factors, safety culture and quality management systems are also desired. Collecting operational experiences has been mainly done regarding the incidents and major failures of components (so called 'event'), which usually demands lots of regulatory resources. This paper concentrates on new information, i.e. lesson learned from recent investigation results of domestic events which contain 5 years' experience. This information can induce many insights for improving operational safety of nuclear power plants (NPPs)

  11. Operating experience of Fugen-HWR in Japan

    Energy Technology Data Exchange (ETDEWEB)

    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 of Fugen-HWR in Japan

    International Nuclear Information System (INIS)

    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

  13. CANDU operating experience

    International Nuclear Information System (INIS)

    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

  14. Industry Operating Experience Process at Krsko NPP

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  16. Spanish Power Exchange Market Concepts and Operating Experience

    International Nuclear Information System (INIS)

    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)

  17. PFR experience of bellows operating in sodium systems

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  19. Operating experience with nuclear power plants 2013; Betriebserfahrungen mit Kernkraftwerken 2013

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  20. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lessel, T [Abwasserverband Ampergruppe, Eichenau/Muenchen (Germany, F.R.); Suess, A [Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Muenchen (Germany, F.R.)

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m/sup 3/ of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs.

  1. Ten year experience in operation of a sewage sludge treatment plant using gamma irradiation

    International Nuclear Information System (INIS)

    Lessel, T.; Suess, A.

    1984-01-01

    The first sewage sludge gamma irradiation plant in a technical scale, using Co-60 has been successfully working in Geiselbullach near Munich, FRG, since July 1973. More than 250,000 m 3 of liquid sludge has been disinfected during that time. Very simple plant design, fully automatic operation over 24 hours and high availability proved the practical applicability of such a facility in a sewage water purification plant without any specially skilled personnel. Beside wide investigations for hygienic aspects, changing of the physical sludge characteristics, effect of irradiated sludge on soil and plants the economic considerations were regarded as important. Experiments were undertaken to optimize the flexibility of the plant operation and to reduce the necessary radiation dose for minimizing the operation costs. (author)

  2. Operating experience: safety perspective

    International Nuclear Information System (INIS)

    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)

  3. Two years of operating experience with the Seattle clinical neutron therapy facility

    International Nuclear Information System (INIS)

    Risler, R.; Brossard, S.; Eenmaa, J.; Kalet, I.; Wootton, P.

    1987-01-01

    After five years of planning, equipment acquisition, facility construction and beam testing the Seattle Clinical Neutron Therapy facility became operational in October 1984. In the past two years nearly 300 people have been treated in clinical trials. During this time 82 % of the planned treatment sessions were performed on schedule, 3 % had to be rescheduled for patient related reasons and 15 % because of equipment problems. The facility is at present running on a 5 days/week schedule: Three ten-hour treatment days, one maintenance day and one research day (radiobiology, therapy related physics). Short runs for short lived isotopes are done between patient treatments. The isocentric gantry, capable of 360 rotation is equipped with a variable collimator with 40 independent leaves. This collimation system allows the use of complex field shapes without the necessity of handling radioactive components like collimator inserts or blocks. It has turned out to be a very essential part for the efficient operation of the facility. Major causes for equipment downtime were associated with the control system, the beryllium target system, RF and magnet systems and the treatment gantry. (author)

  4. Operational and reliability experience with reactor instrumentation

    International Nuclear Information System (INIS)

    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)

  5. Earth-covered storage of LPG - Development, construction and operating experiences

    International Nuclear Information System (INIS)

    Schuldt, P.; Grote, G.

    1990-01-01

    The paper describes the planning, approval procedures, design, fabrication, site-assembling and the testing of liquefied petroleum gas storage tanks. The practical experience after three years of operation is reported. 8 figs

  6. Operating experience feedback program at Olkiluoto NPP

    International Nuclear Information System (INIS)

    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)

  7. Operating experience

    International Nuclear Information System (INIS)

    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

  8. Operational experience of a large area x-ray camera for protein crystallography

    International Nuclear Information System (INIS)

    Joachimiak, A.; Jorden, A. R.; Loeffen, P. W.; Naday, I.; Sanishvili, R.; Westbrook, E. M.

    1999-01-01

    After 3 years experience of operating very large area (210mm x 210mm) CCD-based detectors at the Advanced Photon Source, operational experience is reported. Four such detectors have been built, two for Structural Biology Center (APS-1 and SBC-2), one for Basic Energy Sciences Synchrotrons Radiation Center (Gold-2) at Argonne National Laboratory's Advanced Photon Source and one for Osaka University by Oxford Instruments, for use at Spring 8 (PX-21O). The detector is specifically designed as a high resolution and fast readout camera for macromolecular crystallography. Design trade-offs for speed and size are reviewed in light of operational experience and future requirements are considered. Operational data and examples of crystallography data are presented, together with plans for more development

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  11. 14 CFR 121.434 - Operating experience, operating cycles, and consolidation of knowledge and skills.

    Science.gov (United States)

    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...

  12. Improvement in operating incident experience at the Savannah River Burial Ground

    International Nuclear Information System (INIS)

    Cornman, W.R.

    1979-01-01

    Low-level radioactive wastes generated at the Savannah River Plant and Laboratory are stored at the Savannah River burial ground. These wastes have accumulated from >20 years of reprocessing nuclear fuels and materials for defense programs at the Savannah River Plant. Burial in earthen trenches and aboveground storage for transuranic materials are the principal modes of storage. The infrequent operating incidents that have occurred during the 20-year period have been analyzed. The incidents can be categorized as those causing airborne contamination, waterborne contamination, or vegetation contamination through penetration of plant roots into contaminated soil. Contamination was generally confined to the immediate area of the burial ground. Several incidents occurred because of unintentional burial or exhumation of material. The frequency of operating incidents decreased with operating experience of the burial ground, averaging only about two incidents per year during the last six years of operation

  13. Overview of the SEU project for extended burnup at the Atucha-I NPP. Four years of operating experience

    International Nuclear Information System (INIS)

    Fink, J.M.; Higa, M.; Perez, R.; Pineyro, J.; Sidelnik, J.; Casario, J.A.; Alvarez, L.

    2002-01-01

    Atucha I is a 357 MWe nuclear station moderated and cooled with heavy water, of German design located in Argentina. Fuelling is on-power and the plant was originally fuelled with natural uranium. To reduce fuel costs a program was initiated in August 1993 to introduce gradually slightly enriched uranium (SEU) fuel (0.85 w% U-235) with an associated burnup increase from 5900 MWd/tU to 11300 MWd/tU. The introduction of SEU fuel started in January 1995 and the program was divided in three Phases with an upper limit of SEU FA in the core: 12, 60 and 252 (full core) and licensing documentation was prepared for each Phase. This paper describes the most important aspects of the operating and project experience, and some factors limiting the burnup extension from an operation point of view. After four years of the program and with 181 SEU FA (71%) of the core, the operating experience has been good and without unfavourable effects due to the use of SEU fuel with the only exception of a small increase of the time to reach full power in plant startups or power cycling. In particular, the new criteria to prevent PCI failures in power ramps for higher burnup SEU fuel in refueling operations, plant startups or power cycling has been effective. The average discharge burnup of the SEU fuel taken out of the reactor in 1998 was 11263 MWd/tU. The average discharge burnup of the natural fuel in the same year was 6640 MWd/tU, with an increase of about 12% of the original value for a natural fuel core. The average number of fresh fuel assemblies per full power day was being reduced from 1.31 to 0.92 in 1998 and 0.83 in 1999. The fuel costs dropped gradually during the program from 9.38 (with natural uranium fuel) to 6.57 $/MWh in the first four months of 1999 (taking as reference the NU and SEU FA costs for 1999). Because of this the SEU program has been an important contribution to the reduction of Atucha I operating costs and to the competitiveness of nuclear power generation against

  14. Operating experience review for the AP1000 plant

    International Nuclear Information System (INIS)

    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)

  15. Efeito do tempo de experiência de operadores de Harvester no rendimento operacional Effect of time experience of Harvester operators in operating yield

    Directory of Open Access Journals (Sweden)

    Elaine Cristina Leonello

    2012-12-01

    Full Text Available A mecanização da colheita de madeira permite maior controle dos custos e pode proporcionar reduções em prazos relativamente curtos. Além disso, tem um lugar de destaque na humanização do trabalho florestal e no aumento do rendimento operacional. O presente trabalho teve por objetivo avaliar o desempenho de operadores de harvester em função do tempo de experiência na atividade. Foram avaliados oito operadores do sexo masculino, com idade entre 23 e 46 anos. O estudo consistiu na análise do volume de madeira colhida pelo harvester. O tempo de experiência afeta significativamente o rendimento operacional dos operadores de harvester. Tal rendimento aumenta expressivamente nos primeiros 18 meses de experiência, mantendo-se em ascensão nos próximos 26 meses. Após os 44 meses de experiência, o rendimento dos operadores tende a reduzir, revelando as possíveis acomodações do cotidiano. Tais resultados permitem concluir que por volta dos 50 meses de experiência na atividade de operação de harvester, se faz necessária a adoção de medidas de reciclagem, motivação, entre outras, a fim de proporcionar aos operadores melhores condições de trabalho que os possibilitem continuar exercendo a atividade de forma eficiente e rentável à empresa.The mechanization of timber harvesting allows greater control of costs and can provide reductions in relatively short intervals. Moreover, it has a place in the humanization of the working forest and the increase in performance. This work provides comparisons of operating performance of different operator harvester according to the time of experience in the activity. The operators evaluated were eight males, aged between 23 and 46 years old. The study consisted of analysis of the volume of timber harvested by the harvester. The experience significantly affects the performance of harvesters operators. The performance increases significantly in the first 18 months of experience, and it remained on

  16. Operating experience of a sodium rig following the ingress of oil

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A C; Mehew, R D; Robertson, C M [UKAEA, Dounreay, Thurso, Caithness, Scotland (United Kingdom)

    1980-05-01

    The experience of operating the Small Water Leak Rig at Dounreay in the two years following the ingress into the sodium of silicone oil from the pump is reported. The carbon penetration into the rig pipework has been monitored and has been found to agree with a diffusion model. The predictions based on this model have enabled an operating strategy to be determined to allow continued operation of the rig. (author)

  17. Operating experience of a sodium rig following the ingress of oil

    International Nuclear Information System (INIS)

    Bell, A.C.; Mehew, R.D.; Robertson, C.M.

    1980-01-01

    The experience of operating the Small Water Leak Rig at Dounreay in the two years following the ingress into the sodium of silicone oil from the pump is reported. The carbon penetration into the rig pipework has been monitored and has been found to agree with a diffusion model. The predictions based on this model have enabled an operating strategy to be determined to allow continued operation of the rig. (author)

  18. LAPAROSCOPIC PANCREATIC RESECTION. FROM ENUCLEATION TO PANCREATODUODENECTOMY. 11-YEAR EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Marcel Autran Cesar MACHADO

    Full Text Available Context Our experience with laparoscopic pancreatic resection began in 2001. During initial experience, laparoscopy was reserved for selected cases. With increasing experience more complex laparoscopic procedures such as central pancreatectomy and pancreatoduodenectomies were performed. Objectives The aim of this paper is to review our personal experience with laparoscopic pancreatic resection over 11-year period. Methods All patients who underwent laparoscopic pancreatic resection from 2001 through 2012 were reviewed. Preoperative data included age, gender, and indication for surgery. Intraoperative variables included operative time, bleeding, blood transfusion. Diagnosis, tumor size, margin status were determined from final pathology reports. Results Since 2001, 96 patients underwent laparoscopic pancreatectomy. Median age was 55 years old. 60 patients were female and 36 male. Of these, 88 (91.6% were performed totally laparoscopic; 4 (4.2% needed hand-assistance, 1 robotic assistance. Three patients were converted. Four patients needed blood transfusion. Operative time varied according type of operation. Mortality was nil but morbidity was high, mainly due to pancreatic fistula (28.1%. Sixty-one patients underwent distal pancreatectomy, 18 underwent pancreatic enucleation, 7 pylorus-preserving pancreatoduodenectomies, 5 uncinate process resection, 3 central and 2 total pancreatectomies. Conclusions Laparoscopic resection of the pancreas is a reality. Pancreas sparing techniques, such as enucleation, resection of uncinate process and central pancreatectomy, should be used to avoid exocrine and/or endocrine insufficiency that could be detrimental to the patient's quality of life. Laparoscopic pancreatoduodenectomy is a safe operation but should be performed in specialized centers by highly skilled laparoscopic surgeons.

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

    CERN Document Server

    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...

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  2. Thirty-five years of drift-tube linac experience

    International Nuclear Information System (INIS)

    Knowles, H.B.

    1984-10-01

    The history of the drift-tube linear accelerator (linac) for the first 35 years of its existence is briefly reviewed. Both US and foreign experience is included. Particular attention is given to technological improvements, operational reliability, capital investment, and number of personnel committed to drift-tube linac (DTL) development. Preliminary data indicate that second- and third-generation (post-1960) DTLs have, in the US alone, operated for a combined total period of more than 75 machine-years and that very high reliability (>90%) has been achieved. Existing US drift-tube linacs represent a capital investment of at least $250 million (1983). Additional statistical evidence, derived from the proceedings of the last 11 linear accelerator conferences, supports the view that the DTL has achieved a mature technological base. The report concludes with a discussion of important recent advances in technology and their applications to the fourth generation of DTLs, many of which are now becoming operational

  3. SPIN. First Digital Protection System Feedback of experience ... ... after 30 years

    International Nuclear Information System (INIS)

    Kosicki, M.; Pacuta, J.; Kamga, J.; Burel, J.-P.

    2010-01-01

    In this lecture Mr Burel presents experience with the software SPIN - the first digital protection system feedback. After thirty years of operation, the results are positive: - System is in correct operation and still maintained with spare parts available; - No spurious trip or actuation due to the system itself. A project for modernization is prepared to replace the digital part with a new digital technology designed with today's: - Components (SPINLINE 3); - methods and tools (Software development); - Standards (EMI/RFI - qualification), in order to allow customer to add some new functional needs and to keep the system in operation for thirty more years.

  4. GNF2 Operating Experience

    International Nuclear Information System (INIS)

    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

  5. Choledochal cysts: our ten year experience.

    LENUS (Irish Health Repository)

    Cianci, F

    2012-04-01

    We present our experience in the management of choledochal cysts from 1999 to 2009. A retrospective review of all charts with a diagnosis of choledochal cysts in our institution in this ten-year period. Data was collated using Excel. A total of 17 patients were diagnosed with choledochal cyst: 9 females and 8 males. The average age at diagnosis was 28 months (range from 0 to 9 years). The most common presenting symptoms were obstructive jaundice 6 (35%) and abdominal pain and vomiting 4 (23%). Ultrasound (US) was the initial diagnostic test in all cases with 4 patients requiring further investigations. All patients underwent Roux-en-Y Hepaticojejunostomy. The average length of stay was 11 days. Patients were followed up with Liver Function Tests (LFTS) and US 4-6 weeks post-operatively. Three patients developed complications including post-op collection, high drain output requiring blood transfusion and adhesive bowel obstruction. Our overall experience with choledochal cyst patients has been a positive one with effective management and low complication rates.

  6. Tevatron operational experiences

    International Nuclear Information System (INIS)

    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

  7. An analysis of HANARO operating performance of the year 2001

    International Nuclear Information System (INIS)

    Yoon, D. B.; Choi, H. Y.; Lim, I. C.; Hwang, S. Y.

    2002-01-01

    For the evaluation of operating performance of the HANARO, operation data of the year 2001 were analyzed. Power output, delay times for full-power arrival and shutdown were considered as the representative measures of operating performance. The analysis results show that the total thermal power output is 3770MWD, which is the best record since the startup of the HANARO. The mean values of the delay time for full-power arrival and shutdown are calculated as 3.56 hours and 2.49 hours, respectively. The major causes for the delay of full-power arrival and shutdown are found to be the retardation of the fuel inspection, and unscheduled work for maintenance and experiment. In order to enhance the operating performance, based on the analysis results, biweekly-prearranged plan for working and experiment will be prepared in advance. The starting time of the reactor has been moved up by 1 hour for reaching the full power before the scheduled time. In addition, we will make effort so as to reduce the number of fuels that have to be inspected

  8. ATLAS IBL operational experience

    CERN Document Server

    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.

  9. Early tracking would improve the operative experience of general surgery residents.

    Science.gov (United States)

    Stain, Steven C; Biester, Thomas W; Hanks, John B; Ashley, Stanley W; Valentine, R James; Bass, Barbara L; Buyske, Jo

    2010-09-01

    High surgical complexity and individual career goals has led most general surgery (GS) residents to pursue fellowship training, resulting in a shortage of surgeons who practice broad-based general surgery. We hypothesize that early tracking of residents would improve operative experience of residents planning to be general surgeons, and could foster greater interest and confidence in this career path. Surgical Operative Log data from GS and fellowship bound residents (FB) applying for the 2008 American Board of Surgery Qualifying Examination (QE) were used to construct a hypothetical training model with 6 months of early specialization (ESP) for FB residents in 4 specialties (cardiac, vascular, colorectal, pediatric); and presumed these cases would be available to GS residents within the same program. A total of 142 training programs had both FB residents (n = 237) and GS residents (n = 402), and represented 70% of all 2008 QE applicants. The mean numbers of operations by FB and GS residents were 1131 and 1091, respectively. There were a mean of 252 cases by FB residents in the chief year, theoretically making 126 cases available for each GS resident. In 9 defined categories, the hypothetical model would result in an increase in the 5-year operative experience of GS residents (mastectomy 6.5%; colectomy 22.8%; gastrectomy 23.4%; antireflux procedures 23.4%; pancreatic resection 37.4%; liver resection 29.3%; endocrine procedures 19.6%; trauma operations 13.3%; GI endoscopy 6.5%). The ESP model improves operative experience of GS residents, particularly for complex gastrointestinal procedures. The expansion of subspecialty ESP should be considered.

  10. The design and operation of the slow controls for the DELPHI experiment at LEP

    International Nuclear Information System (INIS)

    Adye, T.J.; Augustinus, A.; Doenszelmann, M.; Rovelli, T.; Sekulin, R.L.; Smith, G.R.

    1994-01-01

    The slow controls of the DELPHI detector enable a single operator to oversee the proper functioning of the apparatus and to diagnose faults as they occur. The hardware and software of this system, as well as their interface to the experiment and the operator, are described. Finally, we attempt to draw some conclusions from seven years' design work and the initial four years' operation of DELPHI. ((orig.))

  11. The design and operation of the slow controls for the DELPHI experiment at LEP

    International Nuclear Information System (INIS)

    Adye, T.J.; Sekulin, R.L.; Smith, G.R.; Augustinus, A.; Rovelli, T.

    1994-03-01

    The slow controls of the DELPHI detector enable a single operator to oversee the proper functioning of the apparatus and to diagnose faults as they occur. The hardware and software of this system, as well as their interface to the experiment and the operator, are described. Finally, we attempt to draw some conclusions from seven years' design work and the initial four years' operation of DELPHI. (author)

  12. Ageing degradation mechanisms in nuclear power plants: lessons learned from operating experience

    International Nuclear Information System (INIS)

    Bieth, M.; Zerger, B.; Duchac, A.

    2014-01-01

    This paper presents main results of a comprehensive study performed by the European Clearinghouse on Operating Experience Feedback of Nuclear Power Plants (NPP) with the support of IRSN (Institut de Surete Nucleaire et de Radioprotection) and GRS (Gesellschaft fuer Anlagen und Reaktorsicherheit mbH). Physical ageing mechanisms of Structures, Systems and Components (SSC) that eventually lead to ageing related systems and components failures at nuclear power plants were the main focus of this study. The analysis of ageing related events involved operating experience reported by NPP operators in France, Germany, USA and to the IAEA/NEA International Reporting System on operating experience for the past 20 years. A list of relevant ageing related events was populated. Each ageing related event contained in the list was analyzed and results of analysis were summarized for each ageing degradation mechanism which appeared to be the dominant contributor or direct cause. This paper provides insights into ageing related operating experience as well as recommendations to deal with the physical ageing of nuclear power plant SSC important to safety. (authors)

  13. Vitrification operational experiences and lessons learned at the WVDP

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Reliability data bank in electronics: ITALTEL experience over 10 years of operation

    International Nuclear Information System (INIS)

    Turconi, G.

    1986-01-01

    The purpose of this paper is to show the Italtel Reliability Data Bank experience in electronics after ten years from data bank creation. Technological evolution on systems and equipment have originated a reliability data bank evolution in order to maintain and improve its performances. This paper will describe the concepts employed to design the today data bank features enabling it to be an important Company tool for reliability activities. (orig.)

  17. Regulatory challenges in using nuclear operating experience

    International Nuclear Information System (INIS)

    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)

  18. IEA-R1 Nuclear Research Reactor: 58 Years of Operating Experience and Utilization for Research, Teaching and Radioisotopes Production

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, Jose Patricio Nahuel; Filho, Tufic Madi; Saxena, Rajendra; Filho, Walter Ricci [Nuclear and Energy Research Institute, IPEN-CNEN/SP, Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP, Av. Prof. Lineu Prestes 2242 Cid Universitaria CEP: 05508-000- Sao Paulo-SP (Brazil)

    2015-07-01

    IEA-R1 research reactor at the Instituto de Pesquisas Energeticas e Nucleares (Nuclear and Energy Research Institute) IPEN, Sao Paulo, Brazil is the largest power research reactor in Brazil, with a maximum power rating of 5 MWth. It is being used for basic and applied research in the nuclear and neutron related sciences, for the production of radioisotopes for medical and industrial applications, and for providing services of neutron activation analysis, real time neutron radiography, and neutron transmutation doping of silicon. IEA-R1 is a swimming pool reactor, with light water as the coolant and moderator, and graphite and beryllium as reflectors. The reactor was commissioned on September 16, 1957 and achieved its first criticality. It is currently operating at 4.5 MWth with a 60-hour cycle per week. In the early sixties, IPEN produced {sup 131}I, {sup 32}P, {sup 198}Au, {sup 24}Na, {sup 35}S, {sup 51}Cr and labeled compounds for medical use. During the past several years, a concerted effort has been made in order to upgrade the reactor power to 5 MWth through refurbishment and modernization programs. One of the reasons for this decision was to produce {sup 99}Mo at IPEN. The reactor cycle will be gradually increased to 120 hours per week continuous operation. It is anticipated that these programs will assure the safe and sustainable operation of the IEA-R1 reactor for several more years, to produce important primary radioisotopes {sup 99}Mo, {sup 125}I, {sup 131}I, {sup 153}Sm and {sup 192}Ir. Currently, all aspects of dealing with fuel element fabrication, fuel transportation, isotope processing, and spent fuel storage are handled by IPEN at the site. The reactor modernization program is slated for completion by 2015. This paper describes 58 years of operating experience and utilization of the IEA-R1 research reactor for research, teaching and radioisotopes production. (authors)

  19. Operational Experience from Solar Thermal Energy Projects

    Science.gov (United States)

    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.

  20. Five years of operating the TRIGA Mainz reactor

    International Nuclear Information System (INIS)

    Benedict, Georg

    1970-01-01

    Considerable obstacles had to be surmounted before TRIGA MAINZ, first TRIGA reactor built in Germany, reached initial criticality in 1965. Subsequent five years' operation did not raise any major problems. The facility has proven quite reliable and particularly well suited for the purposes of the nuclear chemistry research program pursued at Mainz University. Extensive use is made of the pulse mode of operation. As a result, fuel elements are obviously somewhat overstressed, even though most pulses performed are of the 1.50 dollar size. Maximum licensed steady state power of 100 kW till now has met the requirements of most experiments. However, efforts are in progress to improve irradiation conditions by increasing the reactor power to 300 kW. (author)

  1. Operating experience and maintenance at the TRIGA Mark II LENA reactor

    International Nuclear Information System (INIS)

    Cingoli, F.; Altieri, S.; Lana, F.; Rosti, G.; Alloni, L.; Meloni, S.

    1988-01-01

    The last two years at the Trigs Mark II LENA plant were characterized by the running of the n-n-bar oscillation NADIR experiment. Consequently reactor operation was positively affected and the running hours rose again above 1000 hours per year. The LENA team was also deeply involved in the procedures for the renewal of the reactor operation license. The new requirements set by the Nuclear Energy Licensing Authority (ENEA for Italy) most of which concerning radiation protection and environmental impact, have been already fulfilled. In some cases the installation of new apparatus is underway

  2. Clinical experience with the Bentall procedure: 28 years.

    Science.gov (United States)

    Joo, Hyun-Chel; Chang, Byung-Chul; Youn, Young-Nam; Yoo, Kyung-Jong; Lee, Sak

    2012-09-01

    We retrospectively analyzed 28 years of experience with the Bentall procedure in patients with aortic valve, aortic root, and ascending aortic disease. Between March 1982 and December 2010, a total of 218 patients underwent the Bentall procedure using a composite valved conduit. The "inclusion technique" was used in 30 patients (13.8%), the "open-button technique" in 181 patients (83.0%), and the Cabrol technique in 7 patients (3.2%). The early mortality rate was 5.5% (12/218). The mean follow-up duration was 108.0±81.0 months (range: 1-329 months). Seven patients required re-operation, and 1 patient required stent graft insertion at the descending thoracic aorta for progression of aortic arch or descending thoracic aortic dissection or aneurysm after the first operation, and 5 of them had Marfan syndrome. Kaplan-Meier estimated survival rates at 1, 5, 10, 20, and 25 years were 90.4%, 82.7%, 77.6%, 65.3%, and 60.3%, respectively. Freedom from reoperation rates at 1, 5, 10, 20, and 25 years were 99.0%, 98.3%, 95.5%, 90.8%, and 90.8%, respectively. In our experience, the Bentall procedure provided optimal survival with improved functional status. The disease of the aorta may progress, especially in patients with Marfan syndrome. Therefore, careful follow-up with regular computed tomography angiograms should be performed in these patients.

  3. ATLAS distributed computing operation shift teams experience during the discovery year and beginning of the long shutdown 1

    International Nuclear Information System (INIS)

    Sedov, Alexey; Girolamo, Alessandro Di; Negri, Guidone; Sakamoto, Hiroshi; Schovancová, Jaroslava; Smirnov, Iouri; Vartapetian, Armen; Yu, Jaehoon

    2014-01-01

    ATLAS Distributed Computing Operation Shifts evolve to meet new requirements. New monitoring tools as well as operational changes lead to modifications in organization of shifts. In this paper we describe the structure of shifts, the roles of different shifts in ATLAS computing grid operation, the influence of a Higgs-like particle discovery on shift operation, the achievements in monitoring and automation that allowed extra focus on the experiment priority tasks, and the influence of the Long Shutdown 1 and operational changes related to the no beam period.

  4. Magnet operating experience review for fusion applications

    International Nuclear Information System (INIS)

    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

  5. Use of experience for the improvement of technical specifications for operation

    International Nuclear Information System (INIS)

    Schweitz, J.P.; Seveon, J.J.

    1987-11-01

    The lessons drawn from experience led EdF to define in 1980 a national specification standard, to be applied to the first standardized series of 900 MWe units and to be adapted to the later 1300 MWe units. This document is periodically revised, every two years or so, to take into account new trends in safety thinking and lessons learnt from operating experience. In this paper we present the main developments in the field of technical specifications, particularly: the definition of rules applicable in the event of unavailability of safety-related equipment, the integration of plant unit operating feedback for specifications optimization

  6. The Wonderland of Operating the ALICE Experiment

    CERN Document Server

    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...

  7. Feedback of operation and maintenance experience into evolutionary plant design (HWRs)

    International Nuclear Information System (INIS)

    Hedges, K.R.; Sanatkumar, A.; Kwon, Oh-Cheol

    1999-01-01

    The process of feeding back operation and maintenance information into the CANDU plant design process has been in constant evolution since the beginning of the CANDU program. The commissioning and operation experience from the first commercial reactors at Pickering A and Bruce A was used extensively in the design of the first generation CANDU 6 Plants. These units have been in operation for 15 years, producing electricity at an average lifetime capacity factor of about 85%. In further advancing the CANDU 6 and 9 design, greater emphasis is placed on enhancements that can reduce operational costs and further improve plant performance by reducing the planned outage time. The plant design has been improved to facilitate maintenance scheduling, equipment isolation, maintenance and post maintenance testing. Individual tasks have been analyzed as well as the interaction between tasks during outages to reduce the down time required and simplify the execution of the work. This results in shorter outages, reduced radioactive dose and reduced costs. The Utilities have continued to play an important role in CANDU 6 Evolution. Specifically; the Korea Utility KEPCO has one of the original four CANDU 6 Plants and three of the most modem. Their feedback to the designers has been very helpful. One of the most important feedback processes is through the CANDU Owners Group, which provides information exchange between members. In India eight PHWRs of 220 MWe capacity are in operation. Four reactors, also of 220 MWe capacity are in advanced stages of construction. Site construction work of two units of 500 MWe PHWRs at Tarapur will be taken up shortly. Over the years, during construction and operation of these power stations, a large amount of experience has been accumulated. Operation and maintenance experience is shared with operating stations by intensive participation of design engineers in Station Operation Review meetings, trouble shooting and root cause analysis of problems

  8. Radar-based alert system to operate a sewerage network: relevance and operational effectiveness after several years of use.

    Science.gov (United States)

    Faure, D; Payrastre, O; Auchet, P

    2005-01-01

    Since January 2000, the sewerage network of a very urbanised catchment area in the Greater Nancy Urban Community has been operated according to the alarms generated in real time by a storm alert system using weather radar data. This alert system is based on an automatic identification of intense rain cells in the radar images. This paper presents the characteristics of this alert system and synthesises the main results of two complementary studies realised in 2002 in order to estimate the relevance and the operational effectiveness of the alert system. The first study consisted in an off-line analysis of almost 50,000 intense rain cells detected in four years of historical radar data. The second study was an analysis of the experience feedback after two years of operational use of this alert system. The results of these studies are discussed in function of the initial operational objectives.

  9. 40 years of experience in incineration of radioactive waste in Belgium

    International Nuclear Information System (INIS)

    Vanbrabant, R.; Deckers, J.; Luycx, P.; Detilleux, M.; Beguin, Ph.

    2001-01-01

    Since the very beginning of the nuclear activities in Belgium, the incineration of radioactive waste was chosen as a suitable technique for achieving an optimal volume reduction of the produced waste quantities; several R and D projects were realised in this specific field and different facilities were erected and operated. An experimental furnace ''Evence Coppee'' was built in 1960 for treatment of LLW produced by the Belgian Research Centre (SCK/CEN). Regularly this furnace has been modified, improved and equipped with additional installations to obtain better combustion conditions and a more efficient gas cleaning system. Based on the 35 years experience gained by the operation of the ''Evence Coppee'', a completely new industrial incineration installation has been designed in the nineties and commissioned in May 1995, in the frame of the erection of the Belgian Centralised Treatment/Conditioning Facility CILVA. At the end of 1998, the new furnace has burnt 455 tons of solid waste and 246 tons of liquid waste. Besides the conventional incineration process, a High Temperature Slagging Incinerator (HTSI) has been developed, constructed and operated for 10 years in the past. This installation was the combination of an incinerator and a melter producing melted granulated material instead of ashes, and provided experience in the incineration of hazardous waste, such as chlorinated organic compounds and waste with PCB content. The paper presents ''the Belgian Experience'' accumulated year after year with the design and the operation of the above mentioned facilities and demonstrates how the needs required today for a modern installation are met. The paper covers the following aspects; design particularities and description of the systems, operational results for different solid waste categories (bulk waste, precompacted waste, ion exchange resins) and for different liquid waste categories (organic, aqueous, oil), required pretreatment of the waste, ashes conditioning

  10. Regional co-operation in the nuclear field: The Nordic experience

    International Nuclear Information System (INIS)

    Marcus, F.R.

    1983-01-01

    Experience from 25 years of co-operation in the nuclear field between the Nordic countries is described. A pragmatic approach with a minimum of formalism is used. The co-operation takes place mainly through ''horizontal'' channels between corresponding bodies in the different countries - safety authorities, research institutions, electricity producers, etc. In addition, a ''vertical'' co-ordination between these different circles is accomplished through a Nordic Liaison Committee. The experience shows that valuable results can be obtained, mainly through rationalization and improved use of resources. Difficulties, which are inherent in international co-operation, can be reduced, provided that there is a strong political will, an efficient system to promote contacts, and a flexible financing scheme. Apart from the benefits obtained in each of the countries - whether or not it has its own nuclear power - particular advantages accrue when a ''Nordic group'' can present co-ordinated viewpoints on the international scene. (author)

  11. Transporting spent fuel and reactor waste in Sweden experience from 5 years of operation

    International Nuclear Information System (INIS)

    Dybeck, P.; Gustafsson, B.

    1990-01-01

    This paper reports that since the Final Repository for Reactor Waste, SFR, was taken into operation in 1988, the SKB sea transportation system is operating at full capacity by transporting spent fuel and now also reactor waste from the 12 Swedish reactors to CLAB and SFR. Transports from the National Research Center, Studsvik to the repository has recently also been integrated in the system. CLAB, the central intermediate storage for spent fuel, has been in operation since 1985. The SKB Sea Transportation System consists today of the purpose built ship M/s Sigyn, 10 transport casks for spent fuel, 2 casks for spent core components, 27 IP-2 shielded steel containers for reactor waste and 5 terminal vehicles. During an average year about 250 tonnes of spent fuel and 3 -- 4000 m 3 of reactor waste are transported to CLAB and SFR respectively, corresponding to around 30 sea voyages

  12. Operating experiences on ammonia water exchange system at Heavy Water Plant, Talcher (paper No. 6.12)

    International Nuclear Information System (INIS)

    Venkat Ram, D.; Sharma, A.K.

    1992-01-01

    The Heavy Water Plant at Talcher employs bithermal ammonia hydrogen exchange process for the production of heavy water. The paper describes about the existing ammonia water exchange column, its start-up, operating experience and the problems encountered in operation of the column. The operating experiences gained and the data collected over the last few years can be utilised for design and operation of new ammonia water exchange column. (V.R). 2 figs

  13. Fast Flux Test Facility: first three years of operation and future mission

    International Nuclear Information System (INIS)

    Peckinpaugh, C.L.; Newland, D.J.; Evans, E.A.

    1985-03-01

    In summary, the FFTF has proven to be a high performance, versatile test reactor. Results obtained during its first three years of operation - and those to be obtained in the coming years - are building a technology and experience base that is invaluable to future LMRs. The FFTF demonstrates proven LMR technology with a focus for the future and provides the US with international LMR technology leadership

  14. TSTA Piping and Flame Arrestor Operating Experience Data

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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.

  16. Ontario Hydro CANDU operating experience

    International Nuclear Information System (INIS)

    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

  17. Operational experience with superconducting synchrotron magnets

    International Nuclear Information System (INIS)

    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

  18. Operational experience with superconducting synchrotron magnets

    International Nuclear Information System (INIS)

    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

  19. Low-energy house in Arctic climate - 5 years of experience

    DEFF Research Database (Denmark)

    Vladyková, Petra; Rode, Carsten; Kragh, J.

    2011-01-01

    The aim of this article is to present and disseminate the experience gained from a low‐energy house in Sisimiut, Greenland, over the 5 years of operation since its inauguration in April 2005. The house was designed to test and present new low‐energy technologies in the Arctic climate and to impro...

  20. Application of ASSET methodology and operational experience feedback of NPPs in China

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Ziyong [The National Nuclear Safety Administration, Beijing (China)

    1997-10-01

    The introductive presentation of ASSET methodology to China started in March 1992, 3 experts from the IAEA held the ASSET Seminar in Wuhan, China. Three years later, an IAEA seminar on ASSET Method and Operational Experience Feedback proceeded in Beijing on 20-24 March 1995. Another ASSET seminar on Self-Assessment and Operational Experience Feedback was held at Guangdong NPP site on 2-6 December 1996, The NNSA and the GNPP hosted the seminar, 2 IAEA experts, 55 participants from the NPPs, research institutes, the regulatory body (NNSA) and its regional offices attended the seminar. 3 figs, 5 tabs.

  1. Application of ASSET methodology and operational experience feedback of NPPs in China

    International Nuclear Information System (INIS)

    Ziyong Lan

    1997-01-01

    The introductive presentation of ASSET methodology to China started in March 1992, 3 experts from the IAEA held the ASSET Seminar in Wuhan, China. Three years later, an IAEA seminar on ASSET Method and Operational Experience Feedback proceeded in Beijing on 20-24 March 1995. Another ASSET seminar on Self-Assessment and Operational Experience Feedback was held at Guangdong NPP site on 2-6 December 1996, The NNSA and the GNPP hosted the seminar, 2 IAEA experts, 55 participants from the NPPs, research institutes, the regulatory body (NNSA) and its regional offices attended the seminar. 3 figs, 5 tabs

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

    International Nuclear Information System (INIS)

    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)

  3. Operating experience insights supporting ageing assessments

    International Nuclear Information System (INIS)

    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)

  4. Temporal bone paragangliomas: 15 years experience

    Directory of Open Access Journals (Sweden)

    Mehmet Düzlü

    Full Text Available Abstract Introduction Temporal bone paragangliomas (TBPs are benign tumors arising from neural crest cells located along the jugular bulbus and the tympanic plexus. In general surgical excision, radiotherapy and wait-and-scan protocols are the main management modalities for TBPs. Objective In this paper we aim to present our clinical experience with TBPs and to review literature data. Methods The patients who were operated for tympanomastoid paraganglioma (TMP or tympanojugular paraganglioma (TJP in our clinic in the last 15 years were enrolled in the study. A detailed patient's charts review was performed retrospectively. Results There were 18 (52.9% cases with TMPs and 16 (47.1% cases with TJPs, a total of 34 patients operated for TBPs in this time period. The mean age was 50.3 ± 11.7 (range 25-71 years. The most common presenting symptoms were tinnitus and hearing loss for both TMPs and TJPs. Gross total tumor resection was achieved in 17 (94.4% and 10 (62.5% cases for TMPs and TJPs, respectively. Five patients (31.2% with TJP experienced facial palsy following the operation. For all the patients the mean follow-up period was 25.8 months (range 4-108 months. Conclusion In conclusion, based on our findings and literature review, total surgical excision alone or with preoperative embolization is the main treatment modality for TBPs. However radiotherapy, observation protocol and subtotal resection must be considered in cases of preoperative functioning cranial nerves, large tumors and advanced age.

  5. Temporal bone paragangliomas: 15 years experience.

    Science.gov (United States)

    Düzlü, Mehmet; Tutar, Hakan; Karamert, Recep; Karaloğlu, Furkan; Şahin, Muammer Melih; Göcek, Mehmet; Uğur, Mehmet Birol; Göksu, Nebil

    2016-12-08

    Temporal bone paragangliomas (TBPs) are benign tumors arising from neural crest cells located along the jugular bulbus and the tympanic plexus. In general surgical excision, radiotherapy and wait-and-scan protocols are the main management modalities for TBPs. In this paper we aim to present our clinical experience with TBPs and to review literature data. The patients who were operated for tympanomastoid paraganglioma (TMP) or tympanojugular paraganglioma (TJP) in our clinic in the last 15 years were enrolled in the study. A detailed patient's charts review was performed retrospectively. There were 18 (52.9%) cases with TMPs and 16 (47.1%) cases with TJPs, a total of 34 patients operated for TBPs in this time period. The mean age was 50.3± 11.7 (range 25-71 years). The most common presenting symptoms were tinnitus and hearing loss for both TMPs and TJPs. Gross total tumor resection was achieved in 17 (94.4%) and 10 (62.5%) cases for TMPs and TJPs, respectively. Five patients (31.2%) with TJP experienced facial palsy following the operation. For all the patients the mean follow-up period was 25.8 months (range 4-108 months). In conclusion, based on our findings and literature review, total surgical excision alone or with preoperative embolization is the main treatment modality for TBPs. However radiotherapy, observation protocol and subtotal resection must be considered in cases of preoperative functioning cranial nerves, large tumors and advanced age. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  6. Operational experience with synchrotron light interferometers for CEBAF experimental beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov

    2006-10-24

    Beam size and energy spread monitoring systems based on Synchrotron Light Interferometers (SLI) have been in operations at Jefferson Lab for several years. A non-invasive nature and a very high (a few mm) resolution of SLI make these instruments valuable beam diagnostic tools for the CEBAF accelerator. This presentation describes the evolution of the Synchrotron Light Interferometer at Jefferson Lab and highlights our extensive experience in the installation and operation of the SLI for CEBAF experimental beam lines.

  7. TRIGA reactor operating experience

    International Nuclear Information System (INIS)

    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

  8. Ontario Hydro CANDU operating experience

    International Nuclear Information System (INIS)

    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

  9. The LHC test string first operational experience

    CERN Document Server

    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.

  10. Recent experience of Almaraz NPP in operator training

    International Nuclear Information System (INIS)

    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)

  11. Operating experience and TPA: the Italian perspective

    International Nuclear Information System (INIS)

    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

  12. Operation experience with the TRIGA Mark II reactor Vienna in the years 1972 through 1974

    International Nuclear Information System (INIS)

    Boeck, H.

    1974-01-01

    Since the last TRIGA Users Conference in Pavia 1972 the TRIGA reactor Vienna was in operation without any larger undesired shut-down. The integral thermal power production by Sept. 1, 1974 was 3420 MWh. The principal work carried out during the last two years on the reactor system was the installation of a new heat exchanger and primary pump both designed for 1 MW steady state operation. Permission was also obtained from the local authority to withdraw up to 90 m 3 /h secondary cooling water from the well. Some troubles were observed with the pulse rod. After nearly 12 years of operation the connection between the piston rod and control rod broke off just below the water surface. Therefore the piston was shot out without withdrawing the pulse rod itself. After locating the trouble the damage was repaired within one day. The SST fuel elements type 110 were received by the end of 1972 for the purpose of power upgrading. All other fuel elements except one are still located in the reactor core and shifted periodically in order to obtain an optimal burnup. A new alarm system was ordered from Hartmann and Braun and is under installation at the moment. In order to facilitate cooperation with the reactor operation personnel and the experimenters in the reactor hall an accurate power indicator has been installed in the reactor hall which allows all experimenters to read the reactor power as accurately as in the control room itself. (U.S.)

  13. Estimation of fire frequency from PWR operating experience

    International Nuclear Information System (INIS)

    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

  14. How to ensure the safety of extended operations: Practice and experience of Paks NPP

    International Nuclear Information System (INIS)

    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)

  15. Experience gained in two years operation of G1; Experience acquise au cours de deux ans de fonctionnement du reacteur G1

    Energy Technology Data Exchange (ETDEWEB)

    de, Rouville; Pascal, [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Scalliet, [Electricite de France (EDF), 75 - Paris (France)

    1958-07-01

    Technical specifications in respect of the first plutonium generating graphite reactor, the G1 at Marcoule, were stated in a paper read at the first Geneva Conference in 1955. We shall not therefore deal further with the technical characteristics of G1 in the present note, but rather propose to define - in the characteristic fields we think will be of major interest to foreign specialists - the results obtained in two and a half years operation since G1 first became critical on january 7, 1956. (author)Fren. [French] Les caracteristiques techniques du premier reacteur plutonigene, au graphite, de Marcoule, G1, ont ete donnees dans une communication presentee a la premiere conference de Geneve, en 1955. Nous n'y reviendrons donc pas dans la presente note qui a pour objet de faire le point, dans quelques domaines caracteristiques, qui nous ont paru les plus susceptibles d'interesser les specialistes etrangers, des resultats obtenus et des experiences faites au cours des deux annees et demi de fonctionnement du reacteur qui ont suivi sa divergence, le 7 janvier 1956. (auteur)

  16. FFTF operational experience

    International Nuclear Information System (INIS)

    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

  17. Operation experiences with a 30 kV/100 MVA high temperature superconducting cable system

    International Nuclear Information System (INIS)

    Toennesen, Ole; Daeumling, Manfred; Jensen, Kim H; Kvorning, Svend; Olsen, Soeren K; Traeholt, Chresten; Veje, Erling; Willen, Dag; Oestergaard, Jacob

    2004-01-01

    A superconducting cable based on Bi-2223 tape technology has been developed, installed and operated in the public network of Copenhagen Energy in a two-year period between May 2001 and May 2003. This paper gives a brief overview of the system and analyses some of the operation experiences. The aim of this demonstration project is to gain experience with HTS cables under realistic conditions in a live distribution network. Approximately 50 000 utility customers have their electric power supplied through the HTS cable. The cable system has delivered 226 GW h of energy and reached a maximum operating current of 1157 A. The operation experiences include over-currents of 6 kA due to faults on peripheral lines, commissioning, servicing and failure responses on the cooling system, continuous 24 h, 7 day per week monitoring and performance of the alarm system. The implications of these experiences for the future applications of HTS cable systems are analysed

  18. Irradiated Concrete in Nuclear Power Plants: Bridging the Gap in Operational Experience

    International Nuclear Information System (INIS)

    Hohmann, Brian P.; Esselman, Thomas C.; Wall, James J.

    2012-01-01

    The world's fleet of operating nuclear power plants (NPP) has been in-service for more than 20 years. In order to support the increasing demand for inexpensive power, many plants will be required to operate beyond 40 years, which was the original licensing period for existing NPPs. Improved knowledge of the performance of irradiated concrete is required to form a technical basis for long term operation (operation to 80+ years) of nuclear plants around the world. To date, operating experience (OE) of concrete subjected to irradiation has been acceptable, but there is an absence of data on this topic for extended periods of operation. The lack of empirical data has contributed to the difficulty of quantifying the long term behavior of concrete that is experiencing irradiation. Programs are in place that address other degradation mechanisms of concrete, but a clear and focused program is required on the effects of radiation. This paper presents a review of the available literature on the topic of the long-term irradiation effects on the mechanical properties of concrete, and provides a proposed methodology for the characterization of irradiated concrete removed from shut down or decommissioned commercial plants. (author)

  19. Operating experiences since rise-to-power test in high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    Tochio, Daisuke; Watanabe, Shuji; Motegi, Toshihiro; Kawano, Shuichi; Kameyama, Yasuhiko; Sekita, Kenji; Kawasaki, Kozo

    2007-03-01

    The rise-to-power test of the High Temperature Engineering Test Reactor (HTTR) was actually started in April 2000. The rated thermal power of 30MW and the rated reactor outlet coolant temperature of 850degC were achieved in the middle of Dec. 2001. After that, the reactor thermal power of 30MW and the reactor outlet coolant temperature of 950degC were achieved in the final rise-to-power test in April 2004. After receiving the operation licensing at 850degC, the safety demonstration tests have conducted to demonstrate inherent safety features of the HTGRs as well as to obtain the core and plant transient data for validation of safety analysis codes and for establishment of safety design and evaluation technologies. This paper summarizes the HTTR operating experiences for six years from start of the rise-to-power test that are categorized into (1) Operating experiences related to advanced gas-cooled reactor design, (2) Operating experiences for improvement of the performance, (3) Operating experiences due to fail of system and components. (author)

  20. Operation experiences with a 30 kV/100 MVA high temperature superconducting cable system

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Däumling, Manfred; Jensen, Kim Høj

    2004-01-01

    of this demonstration project is to gain experience with HTS cables under realistic conditions in a live distribution network. Approximately 50 000 utility customers have their electric power supplied through the HTS cable. The cable system has delivered 226 GW h of energy and reached a maximum operating current......A superconducting cable based on Bi-2223 tape technology has been developed, installed and operated in the public network of Copenhagen Energy in a two-year period between May 2001 and May 2003. This paper gives a brief overview of the system and analyses some of the operation experiences. The aim...

  1. Impact of LMFBR operating experience on PFBR design

    International Nuclear Information System (INIS)

    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)

  2. Seventeen years of LMFBR experience: Experimental Breeder Reactor II (EBR-II)

    International Nuclear Information System (INIS)

    Perry, W.H.; Lentz, G.L.; Richardson, W.J.; Wolz, G.C.

    1982-01-01

    Operating experience at EBR-II over the past 17 years has shown that a sodium-cooled pool-type reactor can be safely and efficiently operated and maintained. The reactor has performed predictably and benignly during normal operation and during both unplanned and planned plant upsets. The duplex-tube evaporators and superheaters have never experienced a sodium/water leak, and the rest of the steam-generating system has operated without incident. There has been no noticeable degradation of the heat transfer efficiency of the evaporators and superheaters, except for the one superheater replaced in 1981. There has been no need to perform any chemical cleaning of steam-system components

  3. Emergency planning and operating experience

    International Nuclear Information System (INIS)

    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)

  4. ELSA - one year of experience with the Bonn Electron Stretcher Accelerator

    International Nuclear Information System (INIS)

    Althoff, K.H.; Drachenfels, W.v.; Dreist, A.; Husmann, D.; Neckenig, M.; Nuhn, H.D.; Schillo, M.; Schittko, F.J.; Wermelskirchen, C.

    1990-01-01

    One and a half year ago the Bonn Electron Stretcher Accelerator ELSA came into operation. Since then detailed machine studies have been performed between 0.5 and 2 GeV. The control system proved to be a valuable tool for operating the machine. Injection into ELSA including the fast extraction out of the 2.5 GeV booster-synchrotron has been investigated. The adjustment of dipoles and quadrupoles has been checked by closed orbit measurements. The slow extraction at a third integer resonance has been studied in detail. Extraction times up to 200 msec with a duty factor of about 35% are possible. For synchrotron radiation experiments the accumulation and storage of high currents up to 275 mA in ELSA was tested. The beam lifetime (1/e point) at 30 mA is in the order of 15 min. (due to vacuum limitations). Since one year the three experiments have been supplied with external beams. (author) 3 refs., 2 figs., 1 tab

  5. Operating practical experience at Argentina

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Kozloduy NPP - its 20 years operational experience; AEhS `Kozloduy`: 20-letni opyt ehksploatatsii

    Energy Technology Data Exchange (ETDEWEB)

    Yankov, M; Grizanov, I; Sabinov, S [Kombinat Atomna Energetika, Kozloduj (Bulgaria)

    1996-12-31

    The main technical and economic results of 20 year operation of the Kozloduy NPP are summarised. The total electricity produced amounts to more than 200 billions KWh. The energy produced by the plant accounts for more than 40% of the national electricity output since 1993. Details of electricity production in different years by all 6 units are given. The efficiency of units 1-4 (WWER-440) is 29-30% and of units 5-6 (WWER-1000) is 29-33%. The Unit 6 has best characteristics. Since 1989 a safety test is being carried out in cooperation with the IAEA. Units 1 and 2 have been reconstructed in order to enhance safety and reliability. 1 tab.

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

    CERN Document Server

    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.

  9. Destructive operations--a vanishing art in modern obstetrics: 25 year experience at a tertiary care center in India.

    Science.gov (United States)

    Sikka, Pooja; Chopra, Seema; Kalpdev, Arun; Jain, Vanita; Dhaliwal, Lakhbir

    2011-05-01

    Destructive operations have a limited role in modern day obstetrics. In the developed countries, obstetrics has become so advanced that these instruments have actually been put away. However, in developing countries like India, these procedures have a limited role where obstructed labor still continues to plague thousands of women every year and accounts for 8% of maternal deaths. This study was planned to define the changing role of destructive operations in obstetrics over the years as more number of abdominal deliveries are conducted in modern day obstetrics than these procedures. A retrospective analysis of destructive operations performed at the Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India, over a span of 25 years, between 1983 and 2007, was carried out. Of a total of 85,952 deliveries in PGIMER in these 25 years, there were 25,474 cesarean deliveries (29.63%), and 8,826 (10.26%) operative vaginal deliveries. The total number of destructive operations performed was 230 (0.26%). There were 202 craniotomies (87.8%), 13 decapitations (5.7%), 8 eviscerations (3.6%) and 7 cleidotomies (2.9%). There should be an individualized approach to each case of obstructed labor. The health care provider has to decide on the options available to him to deliver the mother by the safest route without causing morbidity and mortality. If the fetus is dead, a destructive procedure can be considered in place of abdominal-route delivery which carries considerable risk to the debilitated mother in neglected labor.

  10. Five Years of Cyclotron Radioisotope Production Experiences at the First PET-CT in Venezuela

    International Nuclear Information System (INIS)

    Colmenter, L.; Coelho, D.; Esteves, L. M.; Ruiz, N.; Morales, L.; Lugo, I.; Sajo-Bohus, L.; Liendo, J. A.; Greaves, E. D.; Barros, H.; Castillo, J.

    2007-01-01

    Five years operation of a compact cyclotron installed at PET-CT facility in Caracas, Venezuela is given. Production rate of 18 F labeled FDG, operation and radiation monitoring experience are included. We conclude that 18 FDG CT-PET is the most effective technique for patient diagnosis

  11. Accelerator/Experiment Operations - FY 2016

    International Nuclear Information System (INIS)

    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.

  12. Accelerator/Experiment Operations - FY 2016

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Programmable DSP-based multi-bunch feedback--operational experience from six installations

    International Nuclear Information System (INIS)

    Fox, J.; Prabhakar, S.; Teytelman, D.; Young, A.; Stover, G.; Drago, A.; Serio, M.; Khan, S.; Knuth, T.; Kim, Y.; Park, M.

    2000-01-01

    A longitudinal instability control system, originally developed for the PEP-II, DAΦNE and ALS machines has in the last two years been commissioned for use at the PLS and BESSY-II light sources. All of the installations are running identical hardware and use a common software distribution package. This common structure is beneficial in sharing expertise among the labs, and allows rapid commissioning of each new installation based on well-understood diagnostic and operational techniques. While the installations share the common instability control system, there are significant differences in machine dynamics between the various colliders and light sources. These differences require careful specification of the feedback algorithm and system configuration at each installation to achieve good instability control and useful operational margins. This paper highlights some of the operational experience at each installation, using measurements from each facility to illustrate the challenges unique to each machine. Our experience on the opportunities and headaches of sharing development and operational expertise among labs on three continents is also offered

  14. [Surgical treatment of esophageal achalasia--20 years experience].

    Science.gov (United States)

    Yaramov, N; Sokolov, M; Angelov, K; Toshev, S; Petrov, B

    2009-01-01

    Achalasia comes from a Greek word that means "failure to relax." Cardiospasm and achalasia refer to the same condition. This report addresses esophageal achalasia--its history, diagnosis, pathophysiology, and treatment options. We report our experience in treating this disorder surgically using modified Heller myotomy combined or not with partial gastric fundoplication. 47 patients with achalasia surgically operated in 20-years period are reported by authors. These features make it reasonable to reasses the relative indications for surgery and nonsurgical therapy in achalasia of the esophagus.

  15. MIT January Operational Internship Experience 2011

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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)

  17. Impact of operating experience on design of civil structures - An overview

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J H.K. [Ontario Hydro, Toronto, ON (Canada)

    1991-04-01

    During the past twenty years, Ontario Hydro has expanded its nuclear power to provide about one third of the electricity used in the province (coal and water powered stations provide the other two thirds). By 1992, the total installed capacity of nuclear generating stations in Ontario will further rise to over 14,000 MW. In common with other power plant design, the layout and structural design of civil facilities for a nuclear generating station are developed from consideration of functional, safety and operational requirements, as well as from past operating experience. Experience on structural performance in the sixteen units of Pickering and Bruce NGS's includes: piping and machinery vibrations, structural fatigue failures, and structural integrity due to extreme loadings not considered in the original design. The operating experience of Ontario Hydro's nuclear stations also indicates that civil structures are subjected to some degree of corrosion or degradation of certain elements similar to other mechanical components in a power station. This category of problems consists of concerns associated with thermal effects on concrete structures due to inoperative cooling system, cracking of concrete, and reliability of elastomeric seal materials at expansion joints of the containment envelop. This paper presents an overview of the operating problems and issues regarding changes in the licensing requirements related to civil structures and supporting systems of major mechanical components. The impact of these generic experience on the design of retrofits and new generating stations is also described in the paper.

  18. Impact of operating experience on design of civil structures - An overview

    International Nuclear Information System (INIS)

    Tang, J.H.K.

    1991-01-01

    During the past twenty years, Ontario Hydro has expanded its nuclear power to provide about one third of the electricity used in the province (coal and water powered stations provide the other two thirds). By 1992, the total installed capacity of nuclear generating stations in Ontario will further rise to over 14,000 MW. In common with other power plant design, the layout and structural design of civil facilities for a nuclear generating station are developed from consideration of functional, safety and operational requirements, as well as from past operating experience. Experience on structural performance in the sixteen units of Pickering and Bruce NGS's includes: piping and machinery vibrations, structural fatigue failures, and structural integrity due to extreme loadings not considered in the original design. The operating experience of Ontario Hydro's nuclear stations also indicates that civil structures are subjected to some degree of corrosion or degradation of certain elements similar to other mechanical components in a power station. This category of problems consists of concerns associated with thermal effects on concrete structures due to inoperative cooling system, cracking of concrete, and reliability of elastomeric seal materials at expansion joints of the containment envelop. This paper presents an overview of the operating problems and issues regarding changes in the licensing requirements related to civil structures and supporting systems of major mechanical components. The impact of these generic experience on the design of retrofits and new generating stations is also described in the paper

  19. Classic intrafascial supracervical hysterectomy (CISH): 10-year experience.

    Science.gov (United States)

    Morrison, John E; Jacobs, Volker R

    2006-01-01

    We report and review herein our 10-year experience with classic intrafascial supracervical hysterectomy focusing on our long-term experience, evolution of the operative technique, and increased use of this technique. We performed a parallel, observational study with retrospective data to evaluate classic intrafascial supracervical hysterectomy, a laparoscopic hysterectomy technique, at Fayette Medical Center, a community hospital in Northwestern Alabama, USA. Patients comprised a consecutive series of 579 over a 10-year period from November 1992 through November 2002. The classic intrafascial supracervical hysterectomy technique, similar to standard supracervical hysterectomy, leaves the cardinal ligament, uterosacral ligament, vascular supply, and innervation to the upper vagina and cervix intact, but unlike supracervical hysterectomy removes the transition zone and endocervical canal. For 579 patients, the average age was 45.4 years (range, 22 to 92), follow-up was 75.3 months (range, 17 to 137), operating room time was 69 minutes (range, 44 to 370), blood loss was 72 mL (range, 10 to 765), length of hospital stay was 23.2 hours (range, 14 hours to 5 days), time to return to work was 13.2 days (range, 3 to 28). Complications include 11 cervical bleedings, 1 uterine artery bleeding, 1 pelvic hematoma, 1 postoperative ileus, and 16 mucoceles of the cervical stump. Three patients were converted from a laparoscopic to an open procedure (0.52%). Long-term follow-up of up to 137 months shows no adverse events thus far. Classic intrafascial supracervical hysterectomy is a safe procedure with a low short- and long-term complication rate. It has a short recuperation period and high patient satisfaction. It is the procedure of choice when hysterectomy is indicated for benign disease.

  20. Accelerator/Experiment Operations - FY 2015

    Energy Technology Data Exchange (ETDEWEB)

    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).

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

    International Nuclear Information System (INIS)

    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)

  2. Operating experience with aluminum bearings at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Langebrake, C.O.

    1975-01-01

    Considerable operating experience has been gained at the Portsmouth Gaseous Diffusion Plant over the last 15 years in the use of aluminum bearings in process related and auxiliary equipment. All of this experience has been excellent and, in several cases, the use of this type of bearing material has solved significant operating problems. Aluminum 850-T101 alloy was first used as a bearing material in purge cascade (PC-9) centrifugal compressors where a fatigue problem was being experienced with babbitt-type bearings. Good experience in this application led to the extended use of this bearing material in other equipment including process related as well as auxiliary equipment. Since 1961 aluminum bearings have been installed in approximately 21 Type PC-9 (centrifugal), 97 Type 9 (centrifugal), 262 Type X-29 (axial), and 101 Type 31 (axial) compressors, and 3 speed increasers in the X-330 Evacuation Booster Station. Based on successful operation of these bearings, continued and expanded use of aluminum bearings is recommended as a means of obtaining a high fatigue resistant bearing at a cost lower than that for babbitt-type bearings. (U.S.)

  3. Cogeneration with natural gas fired internal combustion engines: Italian utility's 10 years operating experience

    International Nuclear Information System (INIS)

    Montermini, G.P.

    1992-01-01

    This paper describes the experience that AGAC, an Italian gas and water utility, has acquired in the operation of a 116 Km long district heating network serving about 40,000 inhabitants. The network is powered by a mix of methane fuelled Otto and diesel cycle engines, coal fired fluidized bed boilers, and methane fired boilers producing annually about 153,000 kW of thermal energy, 2,300 kW of cooling energy, and 28.8 million kWh of electric power. This paper reports on the performance of this system in terms of production and sales trends, equipment efficiency and compatibility with new European Communities air pollution standards

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

    International Nuclear Information System (INIS)

    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.

  5. The design, fabrication, operation and maintenance of (41) 400 H.P.-600 SCFM helium screw compressor systems (Five-year operation report)

    International Nuclear Information System (INIS)

    Pallaver, C.

    1988-12-01

    Fermi National Accelerator Laboratory (Fermilab) uses thirty-four (34) identical compressor systems connected to a common header to supply clean high pressure helium gas feeding 26 refrigerators supplying liquid helium to 777 super conducting magnets. There are seven (7) similar compressor packages in other locations. The purpose of this paper is (after five years of operation) to present all the problems, modifications and experiences associated with the design and operation of these compressor systems

  6. Operating experience and maintenance at the TRIGA Mark II LENA reactor

    International Nuclear Information System (INIS)

    Cingoli, F.; Meloni, S.; Alloni, L.

    1986-01-01

    A summary of reactor operation and maintenance in the time period 1982-1986 is presented and discussed. Some problems occurred from instrumentated aluminum cladded elements. Both of them presented damage in the cable tubes and one element showed a protuberance in the cladding. They were replaced with stainless - steel cladded ones. Both elements were sealed up in stainless - steel tubes and put away in wells, 3 meters deep, in the reactor room floor. Some minor problems, correlated to the quite aid instrumentation of the console, are reported. The reactor activity in the last four years was conditioned by the developing of the n - n-bar oscillation NADIR experiment. The thermal column was dismantled and rebuilt in consideration of the Nadir experiment necessities and this job is described in detail. The building containing, the target and the void pipe, presented in 1982 Conference, are now completely operating and the experiment is running. (author)

  7. Safety and operating experience at EBR-II: lessons for the future

    International Nuclear Information System (INIS)

    Sackett, J.I.; Golden, G.H.

    1981-01-01

    EBR-II is a small LMFBR power plant that has performed safely and reliably for 16 years. Much has been learned from operating it to facilitate the design, licensing, and operation of large commercial LMFBR power plants in the US. EBR-II has been found relatively easy to keep in conformity with evolving safety requirements, largely because of inherent safety features of the plant. Such features reduce dependence on active safety systems to protect against accidents. EBR-II has experienced a number of plant-transient incidents, some planned, others inadvertent; none has resulted in any significant plant damage. The operating experience with EBR-II has led to the formulation of an Operational Reliability Test Program (ORTP), aimed at showing inherently safe performance of fuel and plant systems

  8. Health surveillance in milling, baking and other food manufacturing operations--five years' experience.

    Science.gov (United States)

    Smith, T A; Patton, J

    1999-04-01

    The objective of this study was to describe the incidence of allergic respiratory disease and its outcome in terms of symptoms and jobs, across different flour-using industries. It uses the findings of a health surveillance programme in a large food organization over a five-year period. The population under surveillance consisted of 3,450 employees with exposure to ingredient dusts, of whom 400 were in flour milling, 1,650 in bread baking, 550 in cake baking and 850 in other flour-using operations. A total of 66 employees with either asthma or rhinitis symptoms attributable to sensitization to allergens in the workplace were identified. The majority of these (48/66) had become symptomatic prior to the commencement of the health surveillance programme in 1993. The incidence rates (per million employees per year) for those who developed symptoms between 1993 and 1997 were 550 for flour milling, 1,940 for bread baking, 0 for cake baking and 235 for other flour-using operations. The agent believed to be responsible for symptoms was most commonly grain dust in flour millers and fungal amylase in bread bakers. Wheat flour appeared to have a weaker sensitizing potential than these other two substances. In terms of outcome, at follow-up 18% of symptomatically sensitized employees had left the company. Two of the ex-employees retired through ill health due to occupational asthma. Of those still in employment, 63% described an improvement in symptoms, 32% were unchanged and 4% were worse than when first diagnosed. Over half the cases still in employment were continuing to work in the same job as at the time of diagnosis.

  9. BWR and ABWR operating experience

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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.

  11. 0 + 5 Vascular Surgery Residents' Operative Experience in General Surgery: An Analysis of Operative Logs from 12 Integrated Programs.

    Science.gov (United States)

    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.

  12. Accelerator/Experiment operations - FY 2006

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Radiation therapy with or without primary limited surgery for operable breast cancer: A 20-year experience at the Marseilles Cancer Institute

    International Nuclear Information System (INIS)

    Amalric, R.; Santamaria, F.; Robert, F.

    1982-01-01

    Since 1960 more than 3000 consecutive patients with operable infiltrating breast carcinoma were treated by radiation therapy with or without primary limited surgery, which usually consisted of local excision. For tumors smaller than or equal to 5 cm the ten-year crude survival rate is 77% for patients without palpable axillary nodes (T/sub 1-2/N 0 ) and 63% for patients having axillary adenopathy (T/sub 1-2/N 1 ). For operable tumors exceeding 5 cm in diameter (T 3 N/sub 0-1/) the ten-year crude survival is 34%. Thirty-five percent of the patients alive free of disease at ten years required a secondary operation for presumed local or regional tumor persistence or recurrence, although no residual disease was found in 24% of the operative specimens. Local-regional recurrence had no adverse effect on ten-year survival. This conservative approach offers most women with operable breast cancer an excellent chance at breast preservation with the same chance for ten-year survival as with radical mastectomy

  14. BWR and PWR chemistry operating experience and perspectives

    International Nuclear Information System (INIS)

    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)

  15. Operational experience gained from the Central Brae subsea field

    International Nuclear Information System (INIS)

    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

  16. Experiences of operation for Ikata Nuclear Power Station

    International Nuclear Information System (INIS)

    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.)

  17. Incorporating operational experience and design changes in availability forecasts

    International Nuclear Information System (INIS)

    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)

  18. Experience feedback of operation events in Ling'ao phase Ⅱ nuclear power plant

    International Nuclear Information System (INIS)

    Xiao Zhi; Tao Shusheng; Sun Guochen; Zhang Zengqing

    2012-01-01

    As a new operating nuclear power plant, Ling'ao Phase Ⅱ occurred 20 pieces of operational events in one year of first cycle. By analyzing the events in this paper, the causes of the events are mainly concentrated in three aspects: interface between commissioning and operating, DCS system and the management of human factors. Finally, author gives some suggestions on experience feedback, as a reference to other similar nuclear power plants. (authors)

  19. 10 Years of operating experience of the valves in the safety systems on Caorso plant

    International Nuclear Information System (INIS)

    Curcuruto, S.; Pasquini, M.

    1990-01-01

    The Operating Experience (O.E.) of the valves in the safety related systems on Caorso plant has been analysed. The valves have been grouped according to system, type and manufacturer. All the data on the failures have been respectively drawn out by the O.E. data bank and, in some cases, they have been integrated by informations collected directly on the plant. The events and the relevant causes have been analysed, particularly taking into account the repetitive events. Most of the failures were discovered during the surveillance tests, giving a positive indication of the effectiveness of the periodic test program. It was also that concluded hardware problems caused more failures than human errors both during operation and maintenance. Abnormal distributions of failures on the valves and on their components have been found out. Weak components both mechanical and electrical and pertinent corrective measures have been identified, aimed to eliminate the recurring failure modes

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

    International Nuclear Information System (INIS)

    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)

  1. FACT - Status and experience from five years of operation of the first G-APD Cherenkov Telescope

    Science.gov (United States)

    Neise, D.; Adam, J.; Ahnen, M. L.; Baack, D.; Balbo, M.; Bergmann, M.; Biland, A.; Blank, M.; Bretz, T.; Brügge, K. A.; Buss, J.; Dmytriiev, A.; Dorner, D.; Einecke, S.; Hempfling, C.; Hildebrand, D.; Hughes, G.; Linhoff, L.; Mannheim, K.; Müller, S.; Neronov, A.; Nöthe, M.; Paravac, A.; Pauss, F.; Rhode, W.; Shukla, A.; Temme, F.; Thaele, J.; Walter, R.

    2017-12-01

    The First G-APD Cherenkov Telescope (FACT) demonstrates the usability of novel Geiger-mode operated Avalanche Photo Diodes (G-APD, often called SiPM) for Imaging Atmospheric Cherenkov Telescopes (IACT). The camera consists of 1440 pixels with dedicated electronics operating at 2 Giga samples per second. It is installed on the refurbished HEGRA telescope with a mirror area of ≈ 9.5m2 on the Canary Island La Palma. FACT is taking data almost every night since the camera was installed in October 2011. It was possible to improve the data taking efficiency to very high values due to the very stable and reliable operation. This also allows to operate FACT remotely without any need for operators on site. Even remote human intervention became less and less frequent over the years, allowing operation to become mostly automatic. FACT is monitoring the long-term behavior of some very-high energy variable extra-galactic sources with unparalleled sampling density as well as testing the behavior of the sensors under severe weather conditions. Due to the long exposure of FACT's G-APDs under strong moonlight conditions it was possible to evaluate the aging effects of G-APDs due to collected charge. No indication of aging was found. No external calibration device is needed to operate FACT since the properties of the sensors themselves allow for a high precision self-calibration of the camera.

  2. Construction of a new plant in Gabon by the Compagnie des Mines d'Uranium de Franceville: Three years' experience of operation

    International Nuclear Information System (INIS)

    Jug, V.

    1987-01-01

    As part of a programme to modernize and extend its means of production which had already commenced with the setting up of a solvent extraction unit in 1977, and a sulphuric acid production facility of increased capacity (60 t/d) in 1980, the Compagnie des Mines d'Uranium de Franceville (COMUF) started a new uranium ore treatment plant in 1982. The aim was to replace the older installation built in 1959-60, which had reached the limit of its capacity and whose largest equipment was in need of renewal. The new installations are capable of an annual uranium production of 1500 t of magnesium uranate. The techniques adopted were the most modern, those likely to simplify the process and improve operating costs, namely semi-autogenous grinding and solid-liquid separation using band filters. Three years of operating experience confirm the sound choice of the main options made when designing the installations. The treatment performances, especially those which are independent of the nature of the ore, and the reliability of operation are indeed excellent. Thanks to a training programme started in the late 1980s the staff adapted rapidly to the new technical environment and it has been possible to run the entire plant with almost exclusively Gabonese staff. (author). 1 tab

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

    International Nuclear Information System (INIS)

    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.

  4. USA/FBR program status FFTF operations startup experience

    International Nuclear Information System (INIS)

    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

  5. Paper on operation and maintenance experiences on radiation monitoring instrumentation at NAPS

    International Nuclear Information System (INIS)

    Gupta, J.P.; Vinod Kumar; Sen, S.K.; Malhotra, S.

    2005-01-01

    Narora Atomic Power Station (NAPS) is the first standardized Pressurised Heavy Water Reactor in India commissioned in the year 1989. Many new Radiation Monitoring Systems like Portal Monitors and Ventilation Exhaust Activity Monitors were first time introduced at NAPS. All the Personnel Contamination Monitors and Area Radiation Monitors used at NAPS were designed and developed by Electronics Division, BARC. Only the Portal Monitor was supplied by M/S Herfurth, Germany. The paper highlights the operation and maintenance experiences on Radiation Monitoring Instrumentation at NAPS in the last 15 years of operation. The paper also highlights the different problems faced in Radiation Instruments and our suggestions for improvement in their design for their better availability and long term reliability. (author)

  6. The Laser Ranging Experiment of the Lunar Reconnaissance Orbiter: Five Years of Operations and Data Analysis

    Science.gov (United States)

    Mao, Dandan; McGarry, Jan F.; Mazarico, Erwan; Neumann, Gregory A.; Sun, Xiaoli; Torrence, Mark H.; Zagwodzki, Thomas W.; Rowlands, David D.; Hoffman, Evan D.; Horvath, Julie E.; hide

    2016-01-01

    We describe the results of the Laser Ranging (LR) experiment carried out from June 2009 to September 2014 in order to make one-way time-of-flight measurements of laser pulses between Earth-based laser ranging stations and the Lunar Reconnaissance Orbiter (LRO) orbiting the Moon. Over 4,000 hours of successful LR data are obtained from 10 international ground stations. The 20-30 centimeter precision of the full-rate LR data is further improved to 5-10 centimeter after conversion into normal points. The main purpose of LR is to utilize the high accuracy normal point data to improve the quality of the LRO orbits, which are nomi- nally determined by the radiometric S-band tracking data. When independently used in the LRO precision orbit determination process with the high-resolution GRAIL (Gravity Recovery and Interior Laboratory) gravity model, LR data provide good orbit solutions, with an average difference of approximately 50 meters in total position, and approximately 20 centimeters in radial direction, compared to the definitive LRO trajectory. When used in combination with the S-band tracking data, LR data help to improve the orbit accuracy in the radial direction to approximately 15 centimeters. In order to obtain highly accurate LR range measurements for precise orbit determination results, it is critical to closely model the behavior of the clocks both at the ground stations and on the spacecraft. LR provides a unique data set to calibrate the spacecraft clock. The LRO spacecraft clock is characterized by the LR data to a timing knowledge of 0.015 milliseconds over the entire 5 years of LR operation. We here present both the engineering setup of the LR experiments and the detailed analysis results of the LR data.

  7. Surry Power Station, Units 1 and 2. Annual operating report: January--December 1977, volume I--introduction, summary of operating experience; changes, tests, experiments, and safety-related maintenance; effluent releases; data tabulations

    International Nuclear Information System (INIS)

    1978-01-01

    A chronological operating sequence including shutdowns and occurrences during the year which required load reductions or resulted in non-load related incidents is given. Data are presented concerning plant and procedure changes, tests, experiments, safety related maintenance, effluent releases and personnel radiation exposures

  8. Thirty years experience in ET-RR-1 operation

    International Nuclear Information System (INIS)

    Khattab, M.

    1993-01-01

    Egypt research reactor (ET-R R-1) got critical in 27 Th. July 1961. Since that time many technical problems in system manipulation were raised. The present paper demonstrates the famous events that were initiated and the procedures that were taken for their recovery or mitigation. Maintenance problems are discussed. Reactor parameters measuring systems and control have been modernized. The reactor is investigated by in-service inspection program, (ISI). The results show that reactor vessels surface conditions are in good status. experience obtained from these activities and some proposals for future development are summarized. 6 figs., 1 tab

  9. Complications in paediatric craniofacial surgery: an initial four year experience.

    Science.gov (United States)

    Jones, B M; Jani, P; Bingham, R M; Mackersie, A M; Hayward, R

    1992-04-01

    107 children undergoing transcranial craniofacial surgery in a paediatric hospital have been reviewed to assess the incidence and type of complications which arose. This represents the first 4 years' experience of the craniofacial team. There were no deaths or permanent adverse sequelae of surgery. A total of 53 complications were seen in 42 patients. In 9.3% of patients they were potentially life-threatening, serious in 12.1% and of a minor nature in 28%. The more serious complications were related either to haemorrhage and/or vasovagal shock at operation or to infection post-operatively. Infants undergoing monoblock frontofacial advancements and those with tracheostomies were at particular risk.

  10. Six years of operational experience with a lead acid battery in the autonomous PV-hydrogen plant phoebus Juelich

    Energy Technology Data Exchange (ETDEWEB)

    Meurer, C.; Brocke, W.A.; Emonts, B.; Heuts, G.; Mai, H.; Croe, D. [Forschungszentrum Juelich GmbH, Juelich (Germany). Inst. for Materials and Processes in Energy Systems IWV-3

    1999-07-01

    A set of 110 lead acid battery cells with a capacity of 1380 Ah was operated for six years in the PV-hydrogen plant PHOEBUS Juelich under realistic consumer and solar conditions. The plant is controlled by an energy management system that is specially designed for the use of a battery combined with a hydrogen long-term storage. The energy management system uses the state of charge SOC, which is determined by measurements of the battery current using validated models of the gassing current and the equilibrium voltage. It was found that after six years of operation there is hardly any fading of battery capacity. (orig.)

  11. Operating Experience of MACSTOR Modules at CANDU 6 Stations

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  13. Operational experience with SLAC's beam containment electronics

    International Nuclear Information System (INIS)

    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

  14. Concluding from operating experience to instrumentation and control systems

    International Nuclear Information System (INIS)

    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

  15. Treatment of severe tracheobronchomalacia: Ten-year experience.

    Science.gov (United States)

    de Trey, Lorraine A; Dudley, Julia; Ismail-Koch, Hasnaa; Durward, Andrew; Bellsham-Revell, Hannah; Blaney, Sean; Hore, Ian; Austin, Conal B; Morrison, Gavin A

    2016-04-01

    Paediatric tracheobronchomalacia is a rare but potentially serious condition. Severe tracheobronchomalacia requires intervention or operation. This is an evaluation of a ten-year experience at an institution. In this retrospective study all patients were included that required an intervention for severe tracheobronchomalacia from 2003 to 2012. Symptoms, aetiology, comorbidities, localisation of the malacia, age at diagnosis, therapeutic measures and associated complications were evaluated. Forty-four patients with severe tracheobronchomalacia underwent intervention/operation. The predominant aetiology was vascular compression in 48%. The majority of patients had complex comorbidities, most importantly cardiac pathology in 66%. The median age at diagnosis was 3 months. A total of 17 aortopexies, 21 tracheostomies and 25 stent placements were performed. The mean follow-up was 2.6 years. Severe complications occurred in 12 patients. The most common complications were stent obstruction/fracture and tracheostomy tube obstruction. The management of severe tracheobronchomalacia is complex and the population of patients is very heterogeneous. Therefore the treatment has to be adapted for each patient individually. The decision strategies are discussed in this article. The surgical techniques for placement and safe removal of expandable bare metallic stents employed in our institution are presented. A multidisciplinary team of ENT surgeons, Intensivists, Cardiologists and Cardiac surgeons is of great importance. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  17. Fire protection system operating experience review for fusion applications

    International Nuclear Information System (INIS)

    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

  18. Fire protection system operating experience review for fusion applications

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Operational Experience with the TRIGA Mark II Reactor of the University of Pavia

    Energy Technology Data Exchange (ETDEWEB)

    Tigliole, A. Borio Di; Alloni, D.; Cagnazzo, M.; Coniglio, M.; Lana, F.; Losi, A.; Magrotti, G.; Manera, S.; Marchetti, F.; Pappalardo, P.; Prata, M.; Provasi, M.C.; Salvini, A.; Scian, G.; Vinciguerra, G. [University of Pavia, Laboratory of Applied Nuclear Energy (L.E.N.A), Via Aselli 41, 27100 Pavia (Italy)

    2011-07-01

    The Laboratory of Applied Nuclear Energy (LENA) is an Interdepartmental Research Centre of the University of Pavia which operates a 250 kW TRIGA Mark II Research Nuclear Reactor, a Cyclotron for the production of radioisotopes and other irradiation facilities. The reactor is in operation since 1965 and many home-made upgrading were realized in the past years in order to assure a continuous operation of the reactor for the future. The annual reactor operational time at nominal power is in the range of 300 - 400 hours depending upon the time schedule of some experiments and research activities. The reactor is mainly used for NAA activities, BNCT research, samples irradiation and training. In specific, few tens of hours of reactor operation per year are dedicated to training courses for University students and for professionals. Besides, the LENA Centre hosts every year more than one thousand high school students in visit. Lately, LENA was certified ISO 9001:2008 for the ''operation and maintenance of the reactor'' and for the ''design and delivery of the irradiation service''. Nowadays the reactor shows a good technical state and, at the moment, there are no political or economical reason to consider the reactor shut-down. (author)

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

    International Nuclear Information System (INIS)

    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

  1. Feedback of operating experience in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Feedback of operating experience in nuclear power plants

    International Nuclear Information System (INIS)

    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

  3. Surgical management of gynecomastia: 20 years' experience.

    Science.gov (United States)

    Lapid, O; Jolink, F

    2014-03-01

    Gynecomastia, breast hypertrophy in men, is a common finding. The diagnosis is clinical, and ancillary tests may be performed; however, there is no unanimity in the literature about their use or utility. The mainstay of management is conservative, with a minority of patients being operated on. The surgical treatment of gynecomastia is not restricted to one discipline and is performed by plastic, general, and pediatric surgeons. The aim of this study was to assess the experience treating gynecomastia in a university hospital and the practices of the different surgical disciplines in the diagnosis and surgical treatment of gynecomastia; this knowledge could be used for the formulation of guidelines and the allocation of health-care resources. a university medical center. A retrospective cohort study in which all records of patients operated on for gynecomastia over a 20-year period were retrieved. Data were obtained concerning patient demographics, responsible surgical discipline, the workup and etiology found, the surgical technique used, the occurrence of reoperations and revisions, and the use of pathological examination and its results. A total of 179 patients were treated. There was a difference between the patient groups operated on by the different disciplines regarding the indication, the workup, as well as in the operative techniques used. Plastic surgeons performed more bilateral operations than the other disciplines. Surgeons used more radiology and cytology testing. These results most probably represent differences in the population and pathologies treated. This is possibly due to a bias in the referrals by primary care physicians.

  4. TSTA piping and flame arrestor operating experience data

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. 5-year operation experience with the 1.8 K refrigeration units of the LHC cryogenic system

    CERN Document Server

    Ferlin, G; Claudet, S; Pezzetti, M

    2015-01-01

    Since 2009, the Large Hadron Collider (LHC) is in operation at CERN. The LHC superconducting magnets distributed over eight sectors of 3.3-km long are cooled at 1.9 K in pressurized superfluid helium. The nominal operating temperature of 1.9 K is produced by eight 1.8-K refrigeration units based on centrifugal cold compressors (3 or 4 stages depending to the vendor) combined with warm volumetric screw compressors with sub-atmospheric suction. After about 5 years of continuous operation, we will present the results concerning the availability for the final user of these refrigeration units and the impact of the design choice on the recovery time after a system trip. We will also present the individual results for each rotating machinery in terms of failure origin and of Mean Time between Failure (MTBF), as well as the consolidations and upgrades applied to these refrigeration units.

  6. 5-year operation experience with the 1.8 K refrigeration units of the LHC cryogenic system

    Science.gov (United States)

    Ferlin, G.; Tavian, L.; Claudet, S.; Pezzetti, M.

    2015-12-01

    Since 2009, the Large Hadron Collider (LHC) is in operation at CERN. The LHC superconducting magnets distributed over eight sectors of 3.3-km long are cooled at 1.9 K in pressurized superfluid helium. The nominal operating temperature of 1.9 K is produced by eight 1.8-K refrigeration units based on centrifugal cold compressors (3 or 4 stages depending to the vendor) combined with warm volumetric screw compressors with sub-atmospheric suction. After about 5 years of continuous operation, we will present the results concerning the availability for the final user of these refrigeration units and the impact of the design choice on the recovery time after a system trip. We will also present the individual results for each rotating machinery in terms of failure origin and of Mean Time between Failure (MTBF), as well as the consolidations and upgrades applied to these refrigeration units.

  7. Operating Experience Report: Counterfeit, Suspect and Fraudulent Items. Working Group on Operating Experience. Proceedings and Analysis on an Item of Generic Interest

    International Nuclear Information System (INIS)

    2011-01-01

    The NEA Committee on Nuclear Regulatory Activities (CNRA) believes that sharing operating experience from the national operating experience feedback programmes are a major element in the industry's and regulatory body's efforts to ensure the continued safe operation of nuclear facilities. Considering the importance of these issues, the Committee on the Safety of Nuclear Installations (CSNI) established a working group, PWG no.1 (Principle Working Group Number 1) to assess operating experience in the late 1970's, which was later renamed the Working Group on Operating Experience (WGOE). In 1978, the CSNI approved the establishment of a system to collect international operating experience data. The accident at Three Mile Island shortly after added impetus to this and led to the start of the Incident Reporting System (IRS). In 1983, the IRS database was moved to the International Agency for Atomic Energy (IAEA) to be operated as a joint database by IAEA and NEA for the benefit of all of the member countries of both organisations. In 2006, the WGOE was moved to be under the umbrella of the Committee on Nuclear Regulatory Activities (CNRA) in NEA. In 2009, the scope of the Incident Reporting System was expanded and re-named the International Reporting System for Operating Experience (although, the acronym remains the same). The purpose of WGOE is to facilitate the exchange of information, experience, and lessons learnt related to operating experience between member countries. The working group continues its mission to identify trending and issues that should be addressed in specialty areas of CNRA and CSNI working groups. The CSFI (Counterfeit, Suspect, and Fraudulent Items) issue was determined to be the Issue of Generic Interest at the April 2010 WGOE meeting. The Issue of Generic Interest is determined by the working group members for an in-depth discussion. They are often emerging issues in operating experience that a country or several countries would to the share

  8. Operational safety experience reporting in the United States

    International Nuclear Information System (INIS)

    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)

  9. Proceedings of 2nd PHWR operating safety experience meeting

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Proceedings of 2nd PHWR operating safety experience meeting

    International Nuclear Information System (INIS)

    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

  11. MOX and UOX PWR fuel performances EDF operating experience

    International Nuclear Information System (INIS)

    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)

  12. Dry cooling tower operating experience in the LOFT reactor

    International Nuclear Information System (INIS)

    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

  13. Operational experience with the CMS Data Acquisition System

    CERN Multimedia

    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.

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

    International Nuclear Information System (INIS)

    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

  15. Six years working experience of the Marcoule plant for treatment of irradiated fuel

    International Nuclear Information System (INIS)

    Jouannaud, C.

    1964-01-01

    The irradiated fuel treatment plant at Marcoule began treating rods from the pile G 1 in July 1958. These six years experience of the plant in operation have led to the confirmation or revision of the original ideas concerning the process as well as the technology or methods of exploitation. The process as a whole has suffered little modification, the performances having proved better than originally foreseen; the only alterations made were justified by greater simplicity of operation, better nuclear security (criticality) or for technological reasons. The processes of plutonium reduction from valency IV to valency III by uranium IV, and of concentration of fission product solutions in the presence of formaldehyde, have always given complete satisfaction. The initial concept of direct maintenance of the installations has been justified by experience. Certain maintenance jobs, originally considered impossible after the start of operations, have proved feasible and have been carried out under acceptable conditions; a number of examples are given. From experience it has been possible to define optimal conditions for the design of these installations such as to provide a maximum in robustness and ease of maintenance. The advantages of continuously-operating equipment have been shown. Certain installations have been altered in accordance with these new ideas. Analytical checking in the laboratory has been profoundly modified, and the plans adopted are such that complete safety in work on radioactive solutions is compatible with a very good working speed. Experience has also shown the advantages of having a group on the spot to carry out short-term applied studies. Finally, a strict working discipline and excellent collaboration with the radiation protection service have enabled us to reach the end of these six years, during some of which the exploitation was intensive, without irradiation accident. (authors) [fr

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Design features and operating experiences of neutron measurement system for HANARO

    International Nuclear Information System (INIS)

    Kim, Young Ki; Choi, Young San

    1999-02-01

    This paper discusses unique mechanical and electrical design features of neutron measurement system for HANARO and its operating experiences. Some unexpected problems and misbehaviors during installation and commissioning are briefly introduced. Engineering approaches and procedures in order to solve the problems we are described in priority. It has been proved, through years of operation that the wide range neutron measurement system for HANARO has a good capability of providing the stable and reliable neutron flux signal for reactor control and reactor protection. I hopefully expect that the engineering solutions suggested in this report could be a good reference to the other applications. (Author). 12 refs., 6 tabs., 23 figs

  18. China: EDF's feedback experience of reactor operating is essential to win international markets

    International Nuclear Information System (INIS)

    Maillart, H.

    2016-01-01

    The main assets of EDF on the Chinese nuclear power market is first, its very important feedback experience of reactor operations (EDF cumulates one year of reactor operations every week due to its fleet of 58 reactors), secondly the cooperation with China allowed China to enter nuclear energy in 1983 with the construction of the Daya Bay plant and now to develop its own technology: the CPR-1000 reactor. China is the world leader in terms of nuclear market dynamism with 30 reactors in operation, 24 reactors being built and 40 others planned. A new stage in the Franco-China cooperation would be to share relevant good practices in the managing of both French and Chinese fleets of reactors. EDF has upgraded its commercial international offer, it now proposes to cover all the stages of the nuclear power plant from site selection to plant deconstruction via construction, operation, maintenance and waste management which constitutes a commitment over a 100 year period. (A.C.)

  19. Nuclear power plant operation experience - a feedback programme

    International Nuclear Information System (INIS)

    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)

  20. Telescience testbed: Operational support functions for biomedical experiments

    Science.gov (United States)

    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.

  1. LOFT instrumented fuel design and operating experience

    International Nuclear Information System (INIS)

    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

  2. Nuclear power plant operating experience, 1976

    International Nuclear Information System (INIS)

    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

  3. Cryogenic system operating experience review for fusion applications

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  5. Summary of facility and operating experience on helium engineering demonstration loop (HENDEL)

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Yoshihiro; Fujisaki, Katsuo; Kobayashi, Toshiaki; Kato, Michio; Ota, Yukimaru; Watanabe, Syuji; Kobayashi, Hideki; Mogi, Haruyoshi [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1996-07-01

    The HENDEL is a test facility to perform full scale demonstration tests on the core internals and high temperature components for the High Temperature Engineering Test Reactor(HTTR). The main systems consist of Mother(M) and Adapter(A), fuel stack Test(T{sub 1}) and in-core structure Test(T{sub 2}) sections. The (M+A) section can supply high temperature helium gas to the test section. The M+A section completed in March 1982 has been operated for about 22900 hours till February 1995. The T{sub 1} and T{sub 2} sections, completed in March 1983 and June 1986, have been operated for about 19400 and 16700 hours, respectively. In this period, a large number of tests have been conducted to verify the performance and safety features of the HTTR components. The results obtained from these tests have been effectively applied to the detailed design, licensing procedures and construction of the HTTR. The operating experience of the HENDEL for more than 10 years also brought us establishment of the technique of operation of a large scale helium gas loop, handling of helium gas and maintenance of high temperature facilities. The technique will be available for the operation of the HTTR. This paper mainly describes the summary of plant facirities, operating experience and maintenance on the HENDEL. (author)

  6. 14th Biennial conference on reactor operating experience plant operations: The human element

    International Nuclear Information System (INIS)

    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

  7. Performance and operation experience of the ATLAS SemiConductor Tracker

    CERN Document Server

    Robichaud Veronneau, A; The ATLAS collaboration

    2014-01-01

    After more than 3 years of successful operation at the LHC, we report on the operation and performance of the SemiConductor Tracker (SCT) functioning in a high luminosity, high radiation environment. The SCT is part of the ATLAS experiment at CERN and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors were produced 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 fibers. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to th...

  8. US nuclear power plant operating cost and experience summaries

    International Nuclear Information System (INIS)

    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)

  9. US nuclear power plant operating cost and experience summaries

    Energy Technology Data Exchange (ETDEWEB)

    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).

  10. European Clearinghouse for Nuclear Power Plants Operational Experience Feedback

    International Nuclear Information System (INIS)

    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)

  11. SPEAR 3: the First Year of Operation

    International Nuclear Information System (INIS)

    Hettel, R.O.

    2006-01-01

    The first electrons were accumulated in the newly completed 3-GeV SPEAR 3 storage ring on December 15, 2003, five days after the beginning of commissioning. By mid-January of 2004, 100 mA were stored, the maximum current allowed in the first phase of SPEAR 3 operation, and ring characterization and tuning continued until early March when the first photon beam line was opened for users. After the first year of operation the SPEAR 3 beam properties and ring performance had been extensively measured. These include micron stability using slow orbit feedback, an emittance coupling of ∼0.1% and 50-h lifetimes. The performance of SPEAR 3 during its first year of commissioning and operation and the improvement plans are described

  12. Fort Saint Vrain operational experience

    International Nuclear Information System (INIS)

    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

  13. Comparing PRAs with operating experience

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  15. Overview of ten-year operation of the superconducting linear accelerator at the Spallation Neutron Source

    Science.gov (United States)

    Kim, S.-H.; Afanador, R.; Barnhart, D. L.; Crofford, M.; Degraff, B. D.; Doleans, M.; Galambos, J.; Gold, S. W.; Howell, M. P.; Mammosser, J.; McMahan, C. J.; Neustadt, T. S.; Peters, C.; Saunders, J. W.; Strong, W. H.; Vandygriff, D. J.; Vandygriff, D. M.

    2017-04-01

    The Spallation Neutron Source (SNS) has acquired extensive operational experience of a pulsed proton superconducting linear accelerator (SCL) as a user facility. Numerous lessons have been learned in its first 10 years operation to achieve a stable and reliable operation of the SCL. In this paper, an overview of the SNS SCL design, qualification of superconducting radio frequency (SRF) cavities and ancillary subsystems, an overview of the SNS cryogenic system, the SCL operation including SCL output energy history and downtime statistics, performance stability of the SRF cavities, efforts for SRF cavity performance recovery and improvement at the SNS, and maintenance activities for cryomodules are introduced.

  16. Overview of ten-year operation of the superconducting linear accelerator at the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Kim, Sang-Ho; Afanador, Ralph; Barnhart, Debra L.; Crofford, Mark T.; Degraff, Brian D.

    2017-01-01

    The Spallation Neutron Source (SNS) has acquired extensive operational experience of a pulsed proton superconducting linear accelerator (SCL) as a user facility. Numerous lessons have been learned in its first 10 years operation to achieve a stable and reliable operation of the SCL. In this paper, an overview of the SNS SCL design, qualification of superconducting radio frequency (SRF) cavities and ancillary subsystems, an overview of the SNS cryogenic system, the SCL operation including SCL output energy history and downtime statistics, performance stability of the SRF cavities, efforts for SRF cavity performance recovery and improvement at the SNS, and maintenance activities for cryomodules are introduced.

  17. Operating experience with the Harwell thermo-mechanical generators

    International Nuclear Information System (INIS)

    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)

  18. Ten-year experience of splenic trauma in New Zealand: the rise of non-operative management.

    Science.gov (United States)

    Alamri, Yassar; Moon, Dana; Yen, Damien Ah; Wakeman, Chris; Eglinton, Tim; Frizelle, Frank

    2017-10-06

    The aim of this study was to describe the demographics, mechanisms of injury, management and outcomes in patients who suffered splenic trauma in Christchurch, New Zealand. A retrospective study included all splenic injury patients admitted to Christchurch Public Hospital between January 2005 and August 2015. A total of 238 patients were included, with a median age of 26 years (4-88.7). Of these, 235 patients had blunt injuries. Eighty-nine had high-grade injuries. Yearly admissions of splenic trauma patients have gradually increased. A total of 173 (72.7%) patients were managed with observation; 28 patients (11.8%) had radiological intervention and 37 patients (15.5%) had splenectomy. Patients who died were significantly more likely to be older (median, 46.5 vs 25.2 years, p=0.04) and to have been admitted to ICU (100% vs 32%, p=Splenic injuries have shown a steady increase in the last decade. Splenectomy rates have decreased in favour of non-operative techniques. Radiological intervention with splenic artery embolisation was successful in all selected patients with high-grade injuries.

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

    CERN Document Server

    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. Operational experience using the OSTR flip fuel self-protection program

    International Nuclear Information System (INIS)

    Dodd, B.; Ringle, J.C.; Anderson, T.V.; Johnson, A.G.

    1982-01-01

    Recent changes in NRC Physical Security regulations make it highly desirable for a small number of TRIGA research reactor establishments to maintain each of the fuel elements in their reactor core above the self-protection dose rate criterion. OSTR operations personnel have written a computer program (SPOOF) which calculates the exposure rate (in Rhr -1 ) from an irradiated fuel element at 3 feet in air using the actual operating history of the reactor. The purpose of this current paper is to describe the operational experience gained over the last year and a half while using the SPOOF computer program, and while performing the quarterly dose rate measurements needed to confirm the continuing accuracy of the program, and, most importantly, the self-protection status of the OSTR fuel. The computer program in association with the quarterly dose rate measurements have been accepted by the NRC, and allow the OSTR to take credit for self-protecting FLIP fuel under the current physical security regulations

  1. Ventilation Systems Operating Experience Review for Fusion Applications

    International Nuclear Information System (INIS)

    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

  2. Development of reliability database for safety-related I and C component based on operating experience of KSNP

    International Nuclear Information System (INIS)

    Jang, S. C.; Han, S. H.; Min, K. R.

    2001-01-01

    Reliability database for safety-related I and C components has been developed, based on domestic operating experience of total 8.63 years from four units-Yonggwang Units 3 and 4, and Ulchin Units 3 and 4. This plant-specific data of safety-related I and C components has compared with operating experience for CE-supplied plants in U.S.A. As a results, we found that on the whole the domestic reliability data was similar to CE-supplied plants in USA, through lots of failures occurred early in the commercial operation were included in our analyses without percolation

  3. Safety review of experiments at Albuquerque Operations Office

    International Nuclear Information System (INIS)

    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

  4. Nine Years of XMM-Newton Pipeline: Experience and Feedback

    Science.gov (United States)

    Michel, Laurent; Motch, Christian

    2009-05-01

    The Strasbourg Astronomical Observatory is member of the Survey Science Centre (SSC) of the XMM-Newton satellite. Among other responsibilities, we provide a database access to the 2XMMi catalogue and run the part of the data processing pipeline performing the cross-correlation of EPIC sources with archival catalogs. These tasks were all developed in Strasbourg. Pipeline processing is flawlessly in operation since 1999. We describe here the work load and infrastructure setup in Strasbourg to support SSC activities. Our nine year long SSC experience could be used in the framework of the Simbol-X ground segment.

  5. Nine Years of XMM-Newton Pipeline: Experience and Feedback

    International Nuclear Information System (INIS)

    Michel, Laurent; Motch, Christian

    2009-01-01

    The Strasbourg Astronomical Observatory is member of the Survey Science Centre (SSC) of the XMM-Newton satellite. Among other responsibilities, we provide a database access to the 2XMMi catalogue and run the part of the data processing pipeline performing the cross-correlation of EPIC sources with archival catalogs. These tasks were all developed in Strasbourg. Pipeline processing is flawlessly in operation since 1999. We describe here the work load and infrastructure setup in Strasbourg to support SSC activities. Our nine year long SSC experience could be used in the framework of the Simbol-X ground segment.

  6. Operational Experience of Nuclear Fuel in Finnish Nuclear Power Plants (with Emphasis on WWER Fuel)

    International Nuclear Information System (INIS)

    Teraesvirta, R.

    2009-01-01

    The four operating nuclear reactors in Finland, Loviisa-1 and -2 and Olkiluoto-1 and -2 have now operated approximately 30 years. The overall operational experience has been excellent. Load factors of all units have been for years among the highest in the world. The development of the fuel designs during the years has enabled remarkable improvement in the fuel performance in terms of burnup. Average discharge burnup has increased more than 30 percent in all Finnish reactor units. A systematic inspection of spent fuel assemblies, and especially all failed fuel assemblies, is a good and useful practise employed in Finland. A possibility to inspect the fuel on site using a pool side inspection facility is a relatively economic way to find out root causes of fuel failures and thereby facilitate developing remedies to prevent similar failures in the future

  7. Radiation protection issues after 20 years of LHC operation

    CERN Document Server

    Forkel-Wirth, D.; Roesler, S.; Theis, C.; Ulrici, L.; Vincke, H.; Vincke, Hz.

    2011-01-01

    Since November 2009, the LHC commissioning progresses very well, both with proton and lead beams. It will continue in 2011 and nominal LHC operation is expected to be attained in 2013. In parallel, plans for various LHC upgrades are under discussion, suggesting a High-Luminosity (HL) upgrade first and a High-Energy (HE) upgrade in a later state. Whereas the upgrade in luminosity would require the modification of only some few key accelerator components like the inner triplets, the upgrade in beam energy from 7 TeV to 16.5 TeV would require the exchange of all dipoles and of numerous other accelerator components. The paper gives an overview of the radiation protection issues related to the dismantling of LHC components prior to the installation of the HE-LHC components, i.e. after about 20 years of LHC operation. Two main topics will be discussed: (i) the exposure of workers to ionizing radiation during the dismantling of dipoles, inner triplets or collimators and experiments and (ii) the production, condition...

  8. ATLAS Distributed Computing Operations: Experience and improvements after 2 full years of data-taking

    International Nuclear Information System (INIS)

    Jézéquel, S; Stewart, G

    2012-01-01

    This paper summarizes operational experience and improvements in ATLAS computing infrastructure in 2010 and 2011. ATLAS has had 2 periods of data taking, with many more events recorded in 2011 than in 2010. It ran 3 major reprocessing campaigns. The activity in 2011 was similar to 2010, but scalability issues had to be addressed due to the increase in luminosity and trigger rate. Based on improved monitoring of ATLAS Grid computing, the evolution of computing activities (data/group production, their distribution and grid analysis) over time is presented. The main changes in the implementation of the computing model that will be shown are: the optimization of data distribution over the Grid, according to effective transfer rate and site readiness for analysis; the progressive dismantling of the cloud model, for data distribution and data processing; software installation migration to cvmfs; changing database access to a Frontier/squid infrastructure.

  9. Operation experience of the Indonesian multipurpose research reactor RSG-GAS

    Energy Technology Data Exchange (ETDEWEB)

    Hastowo, Hudi; Tarigan, Alim [Multipurpose Reactor Center, National Nuclear Energy Agency of the Republic of Indonesia (PRSG-BATAN), Kawasan PUSPIPTEK Serpong, Tangerang (Indonesia)

    1999-08-01

    RSG-GAS is a multipurpose research reactor with nominal power of 30 MW, operated by BATAN since 1987. The reactor is an open pool type, cooled and moderated with light water, using the LEU-MTR fuel element in the form of U{sub 3}O{sub 8}-Al dispersion. Up to know, the reactor have been operated around 30,000 hours to serve the user. The reactor have been utilized to produce radioisotope, neutron beam experiments, irradiation of fuel element and its structural material, and reactor physics experiments. This report will explain in further detail concerning operational experience of this reactor, i.e. reactor operation data, reactor utilization, research program, technical problems and it solutions, plant modification and improvement, and development plan to enhance better reactor operation performance and its utilization. (author)

  10. Operation experience of the Indonesian multipurpose research reactor RSG-GAS

    International Nuclear Information System (INIS)

    Hastowo, Hudi; Tarigan, Alim

    1999-01-01

    RSG-GAS is a multipurpose research reactor with nominal power of 30 MW, operated by BATAN since 1987. The reactor is an open pool type, cooled and moderated with light water, using the LEU-MTR fuel element in the form of U 3 O 8 -Al dispersion. Up to know, the reactor have been operated around 30,000 hours to serve the user. The reactor have been utilized to produce radioisotope, neutron beam experiments, irradiation of fuel element and its structural material, and reactor physics experiments. This report will explain in further detail concerning operational experience of this reactor, i.e. reactor operation data, reactor utilization, research program, technical problems and it solutions, plant modification and improvement, and development plan to enhance better reactor operation performance and its utilization. (author)

  11. Operational experience with CMS Tier-2 sites

    International Nuclear Information System (INIS)

    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. Vacuum system operating experience review for fusion applications

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

  14. System contamination and radiological aspects after 12 years' operation of KNK I/II

    International Nuclear Information System (INIS)

    Finke, G.; Richard, H.; Menges, K.H.

    1984-01-01

    After 12 years operation of KNK I and KNK II a survey is given of experience with radiation control and other radiological aspects at KNK like main sources of radiation with respect to personnel exposure, the behaviour and share of impurities and fission products in the primary circuits and the possibilities of influence to get personnel doses as low as possible. The amount of liquid and solid waste and the discharges of the plant stack are figured. This experience at KNK confirms the good experiences with other LMFBRs but also shows, that we have to focus our attention on the further development of the radiation level in the primary cell and on careful timing of any work in this area. (author)

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Operating experience with nuclear power stations in Member States in 2002

    International Nuclear Information System (INIS)

    2003-11-01

    This report is the thirty-fourth in the Agency's series of annual reports on operating experience with nuclear power stations in Member States. The report is a direct output from the Agency's Power Reactor Information System (PRIS), whose database contains all operating experience data published in the Agency's operating experience annual reports since 1971 and basic information on power reactors, including design data. It presents operating experience data for all worldwide nuclear power plants after starting commercial operation. The PRIS databank is available free of charge to IAEA Member States through its two services: PRIS-PC and MicroPRIS. The PRIS-PC allows direct access to the database via telephone lines or through the Internet. The MicroPRIS contains a subset of the PRIS database and is a personal computer version of PRIS data available on diskette in a form readily accessible by standard, commercially available personal computer packages. PRIS is also available in the Internet at http://www.iaea.org/programmes/a2. Load, operation and availability factors are used as the basic performance factors. Energy unavailability factors, separate for planned and unplanned unavailability, due either to causes in the plant or causes external to the plant, are used as a measure of energy lost through a unit not being available. However, some ambiguity remains in the operator reports of the unavailability data, resulting in inconsistencies in these factors. It is recognized that there is an inherent difficulty in reporting unavailability in energy with relation to a maximum capacity which may change several times during the year. In addition, there are different practices in reporting planned and unplanned unavailability among Member States. The unavailability factors in this report should therefore be used with caution. It should be noted that, for load, operation and unavailability factors, there might be differences between the data of this report and those

  18. Proceedings of the specialist meeting on nuclear fuel and control rods: operating experience, design evolution and safety aspects

    International Nuclear Information System (INIS)

    1997-01-01

    Design and management of nuclear fuel has undergone a strong evolution process during past years. The increase of the operating cycle length and of the discharge burnup has led to the use of more advanced fuel designs, as well as to the adoption of fuel efficient operational strategies. The analysis of recent operational experience highlighted a number of issues related to nuclear fuel and control rod events raising concerns about the safety aspects of these new designs and operational strategies, which led to the organisation of this Specialists Meeting on fuel and control rod issues. The meeting was intended to provide a forum for the exchange of information on lessons learned and safety concern related to operating experience with fuel and control rods (degradation, reliability, experience with high burnup fuel, and others). After an opening session 6 papers), this meeting was subdivided into four sessions: Operating experience and safety concern (technical session I - 6 papers), Fuel performance and operational issues (technical session II - 7 papers), Control rod issues (technical session III - 9 papers), Improvement of fuel design (technical session IV.A - 4 papers), Improvement on fuel fabrication and core management (technical session IV.B - 6 papers)

  19. Operation experience with elevated ammonia

    International Nuclear Information System (INIS)

    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.)

  20. Operational experience feedback with precursor analysis

    International Nuclear Information System (INIS)

    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

  1. Primary water chemistry of VVERs-operating experience

    International Nuclear Information System (INIS)

    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.)

  2. Summary of W7-AS results after 14 years of operation

    International Nuclear Information System (INIS)

    Jaenicke, R.

    2003-01-01

    The experiments on the Stellarator W7-AS ceased on July 31, 2002 according to schedule. W7-AS itself resulted out of replacing the torus vessel with helical windings of the classical stellarator W7-A by modular field coils and a new torus vessel. On W7-A ohmic heating was the only available heating method at the start of the experiments. The partial optimized stellarator W7-AS was designed for net current free operation and consequently equipped - from the very beginning - with powerful ECRH. The NBI heating system was upgraded several times, and heating by ICRH in 3D magnetic field configurations was demonstrated successfully. The paper summarises essential results obtained during 14 years of operation. Since W7-AS was a first step in the development of optimized stellarators, its main task was to verify the predictions of the optimization procedure applied to the design of the fully optimized W7-X by means of experiments as far as possible. And thus, W7-AS has clearly proven that it is possible - to produce magnetic flux surfaces of high quality with modular field coils - to reduce the Pfirsch-Schlueter currents - to predict neoclassical transport in 3D magnetic field configurations by the DKES code - to calculate the bootstrap current on the basis of neoclassical theory - to obtain high β-values without evident limitation by instabilities and - to use the island divertor as an effective divertor concept in 3D magnetic field configurations. Other highlights found more by chance during the operation of W7-AS are e.g. the discovery of high confinement regimes such as the first H-mode discharges in stellarators as well as discharges with transport barriers (ion and electron root) wherein maximum energy confinement times (more than 60 ms) and maximum ion (up to 1.7 keV) and electron temperatures (up to 6.8 keV) were obtained. For sufficiently low impurity levels, very high densities (up to 4.10 20 m -3 ) were accessible and limited by radiative collapse only. A

  3. FRG compact core - one year experience

    International Nuclear Information System (INIS)

    Knop, W.; Schreiner, P.

    2001-01-01

    The GKSS research centre Geesthacht GmbH operates the MTR-type swimming pool reactor FRG-1 (5 MW) for more than 40 years. The FRG-1 has been upgraded and refurbished many times to follow the changing demands of safe operation and today's needs of high neutron flux for scientific research. High neutron fluxes with highest availability is the permanent demand of the science on the operation of a neutron source. (orig.)

  4. Experience in operation of heavy water reactors

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  6. Operating experience and performance at Narora Atomic Power Station

    International Nuclear Information System (INIS)

    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)

  7. Power ramping/cycling experience and operational recommendations in KWU power plants

    International Nuclear Information System (INIS)

    Jan, R. von; Wunderlich, F.; Holzer, R.

    1980-01-01

    The power cycling and ramping experience of KWU is based on experiments in test and commercial reactors, and on evaluation of plant operation (PHWR, PWR and BWR). Power cycling of fuel rods have never lead to PCI failures. In ramping experiments, for fast ramps PCI failure thresholds of 480/420 W/cm are obtained at 12/23 GWd/t(U) burn-up for pressurized PWR fuel. No failures occurred during limited exceedance of the threshold with reduced ramp rate. Operational recommendations used by KWU are derived from experiments and plant experience. The effects of ramping considerations on plant operation is discussed. No rate restrictions are required for start-ups during an operating cycle or load follow operation within set limits for the distortion of the local power distribution. In a few situations, e.g. start-up after refueling, ramp rates of 1 to 5 %/h are recommended depending on plant and fuel design

  8. Operating procedures: Fusion Experiments Analysis Facility

    Energy Technology Data Exchange (ETDEWEB)

    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

    International Nuclear Information System (INIS)

    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. From USA operation experience of industrial uranium-graphite reactors

    International Nuclear Information System (INIS)

    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

  11. Construction and Operational Experience with a Superconducting Octupole Used to Trap Antihydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Wanderer P.; Escallier, J.; Marone, A.; Parker, B.

    2011-09-06

    A superconducting octupole magnet has seen extensive service as part of the ALPHA experiment at CERN. ALPHA has trapped antihydrogen, a crucial step towards performing precision measurements of anti-atoms. The octupole was made at the Direct Wind facility by the Superconducting Magnet Division at Brookhaven National Laboratory. The magnet was wound with a six-around-one NbTi cable about 1 mm in diameter. It is about 300 mm long, with a radius of 25 mm and a peak field at the conductor of 4.04 T. Specific features of the magnet, including a minimal amount of material in the coil and coil ends with low multipole content, were advantageous to its use in ALPHA. The magnet was operated for six months a year for five years. During this time it underwent about 900 thermal cycles (between 4K and 100K). A novel operational feature is that during the course of data-taking the magnet was repeatedly shut off from its 950 A operating current. The magnet quenches during the shutoff, with a decay constant of 9 ms. Over the course of the five years, the magnet was deliberately quenched many thousands of times. It still performs well.

  12. Ten years experience with a large computerized TLD-personnel monitoring system

    International Nuclear Information System (INIS)

    Duftschmid, K.E.

    1986-01-01

    It is now ten years since our Institute for Radiation Protection has fully replaced its filmdosimetry service by a computerized automated TLD system. Presently more than 13000 radiation workers are monthly monitored by three automated TLD readers linked to the computer center. The paper describes system hardware and software and experience gained in long-term routine operation. In particular the introduction of the new ICRU quantities for personnel dosimetry in the existing TLD system is discussed. (Author)

  13. Bituminization of radioactive wastes at the Nuclear Research Center Karlsruhe. Experience from plant operation and development work

    Energy Technology Data Exchange (ETDEWEB)

    Hild, W; Kluger, W; Krause, H

    1976-05-01

    A summary is given of the main operational experience gained at the Nuclear Research Center Karlsruhe in 4 years operation of the bituminization plant for evaporator concentrates from low- and medium level wastes. At the same time some of the essential results are compiled that have been obtained in the R + D activities on bituminization.

  14. LMFBR operational safety: the EBR-II experience

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  16. Recurring events, and the Possible Need to Reinforce Operating Experience Feedback Programs

    International Nuclear Information System (INIS)

    Ross, Denwood

    1999-09-01

    A nuclear power plant is designed for a spectrum of incidents and accidents, ranging from a reactor trip without other complications to more serious events such as pipe ruptures. Certain portions of the plant are designed for even more significant events such as severe accidents. Several thousand reactor years of experience have been recorded and many postulated events have in fact occurred. In some instances the same or similar event has occurred more than once within a single country or among several nations. Such cases are referred to as recurring events. One way to reduce the likelihood, or severity (or both) of recurrence is to maintain and utilize a system for reporting of events, both at the national and the international levels. The international system is referred as the Incident Reporting System. Events to be reported to IRS include: - The event itself is serious or important in terms of safety due to an actual or potential reduction in the plant's defense in depth; - The event reveals important lessons learned that will help the international community to prevent its recurrence as a safety significant event under aggravated conditions or to avoid the occurrence of a serious or important event in terms of safety; - The event is a repetition of a similar event previously reported to IRS, but highlights new important lessons learned for the international community. National systems for reporting of events vary in scope; there is guidance on systems for feedback of experience from events in nuclear power plants. Further, the Nuclear Safety Convention, Article 19 - Operation - provides (section vii) that each Contracting Party shall take the appropriate steps to ensure that 'programmes to collect and analyse operating experience are established, the results obtained and the conclusions drawn are acted upon and that existing mechanisms are used to share important experience with international bodies and with other operating organizations and regulatory bodies

  17. Tracking versus fixed flat-plate arrays: Experimental results of one year's operation at Adrano pilot plant

    International Nuclear Information System (INIS)

    Guastella, S.; Iliceto, A.; Piazza, V.

    1988-01-01

    To investigate the cost/benefits of sun-tracking photovoltaic (PV) systems as compared with fixed arrays, an experiment is under way at the Adrano PV plant in Italy to look into the performance of actually operating systems. This paper reports both theoretical evaluations on energy gain achievable with tracking PV plants and actual data collected over a year of continuous operation. Such data allow an analysis of financial viability, herein presented for a particular PV installation

  18. An overview of KANUPP operating experience in chemistry

    International Nuclear Information System (INIS)

    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)

  19. Operating experience gained during the copper oxide plugging incident in Koeberg unit 1 generator stator

    International Nuclear Information System (INIS)

    Mellor, S.P.; Matthee, F.W.

    2002-01-01

    In June 1999 Koeberg's unit 1 started to experience adverse operating conditions which were later ascribed to blockages in the hollow conductors of the generator stator. These blockages were attributed to copper oxide plugs which developed progressively during the following year and culminated in reduced power operation. Many attempts were made to address the plugging by implementing various off-line and on-line cleaning processes. Subsequent to a successful on-line cleaning operation, the unit was returned to full power and the chemistry regime for the stator cooling water system was changed to allow for operation at an elevated pH. This paper discusses Koeberg's experience with copper oxide blockages, describes the initial indications of the problem and the impact on the operating parameters. The remainder of the paper focuses on the actions taken to address the deteriorating situation and the different cleaning methods implemented to remove the copper oxide deposits. The paper concludes with the current status of the unit 1 generator stator and the lessons learned during the resolution of this problem. (authors)

  20. Operating experience gained during the copper oxide plugging incident in Koeberg unit 1 generator stator

    Energy Technology Data Exchange (ETDEWEB)

    Mellor, S.P.; Matthee, F.W. [ESKOM, Koeberg Nuclear Power Station (South Africa)

    2002-07-01

    In June 1999 Koeberg's unit 1 started to experience adverse operating conditions which were later ascribed to blockages in the hollow conductors of the generator stator. These blockages were attributed to copper oxide plugs which developed progressively during the following year and culminated in reduced power operation. Many attempts were made to address the plugging by implementing various off-line and on-line cleaning processes. Subsequent to a successful on-line cleaning operation, the unit was returned to full power and the chemistry regime for the stator cooling water system was changed to allow for operation at an elevated pH. This paper discusses Koeberg's experience with copper oxide blockages, describes the initial indications of the problem and the impact on the operating parameters. The remainder of the paper focuses on the actions taken to address the deteriorating situation and the different cleaning methods implemented to remove the copper oxide deposits. The paper concludes with the current status of the unit 1 generator stator and the lessons learned during the resolution of this problem. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  2. Radiation treatment of sewage sludge - experience with an operating pilot plant

    International Nuclear Information System (INIS)

    Suess, A.; Lessel, T.

    1977-01-01

    After an operation time of a pilot plant for the γ-irradiation of sewage sludge after 3 years promising results could be obtained for economic considerations, killing rate of pathogenes and radiation induced changes in sedimentation properties. Irradiated sewage sludge indicated nearly the same effect on soil and plant as untreated. No special trained personnel are necessary for maintenance because of the simple design. Successful experience during 18 months resulted in an increase of the daily capacity up to 120 m 3 from December 1975. (author)

  3. Inspection, maintenance and voyage repair experiene during 10 years operation of the N.S. Savannah

    International Nuclear Information System (INIS)

    Jackson, E.L. Jr.

    1978-01-01

    This paper covers the development and performance of annual inspections on the N.S. Savannah over a 10 year period. Modifications and revisions to the inspection criteria were made during this period without sacrificing the safe performance of the reactor plant. The inspection experience gained during this period provides a information for future safe nuclear ship operations

  4. Improving the Sharing and Use of Operating Experience Among Pressurized Heavy Water Reactors

    International Nuclear Information System (INIS)

    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

  5. Operational experience of extreme wind penetrations

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  6. Operational experience of the ATLAS accelerator

    Energy Technology Data Exchange (ETDEWEB)

    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. Preheat operating experiences at the FFTF

    International Nuclear Information System (INIS)

    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

  8. Operating experience on radiation reduction in the latest BWRs

    International Nuclear Information System (INIS)

    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.)

  9. PLASMA-F experiment: Three years of on-orbit operation

    Czech Academy of Sciences Publication Activity Database

    Zelenyi, L. M.; Zastenker, G. N.; Petrukovich, A. A.; Chesalin, L. S.; Nazarov, V. N.; Prokhorenko, V. I.; Balaz, J.; Kúdela, J.; Strgarski, I.; Slivka, M.; Gladyshev, V. A.; Kirpichev, I. P.; Sarris, E.; Sarris, T.; Lakutina, E. V.; Minskaya, L. K.; Krukovskaya, E. V.; Beznos, A. V.; Markov, Y. I.; Tretyakov, A. E.; Batanov, O. V.; Korotkov, F. V.; Melnik, A. P.; Konoplev, V. V.; Ryabova, A. D.; Gevorkov, E. V.; Klimenchenko, M. V.; Bazhenov, A. G.; Belova, I. E.; Gavrilova, E. A.; Ananenkova, A. N.; Rudnevskaya, L. V.; Dyachkov, A. V.; Starostina, O. A. (ed.); Ryazanova, E. E.; Eismont, N. A.; Šafránková, J.; Němeček, Z.; Přech, L.; Cermak, I.; Vaverka, J.; Komárek, A.; Vojta, Jaroslav; Karimov, B. T.; Agafonov, Y. N.; Borodkova, N. L.; Gagua, T. I.; Gagua, I. T.; Koloskova, I. V.; Leibov, A. V.; Parhomov, V. A.; Ryazanceva, M. O.; Khrapchenkov, V. V.; Chugunova, O. M.

    2015-01-01

    Roč. 49, č. 7 (2015), s. 580-603 ISSN 0038-0946 Institutional support: RVO:68378289 Keywords : solar wind * Earth magnetosphere * magnetosheath * plasma energy spectrometer * energetic particle monitor Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.638, year: 2015 http://link.springer.com/article/10.1134%2FS0038094615070230

  10. Summary of operating experience at Swedish nuclear power plants in 1984

    International Nuclear Information System (INIS)

    1985-01-01

    The four owners on nuclear power plants in Sweden - The Swedish State Power Board, Forsmarks Kraftgrupp AB, Sydkraft AB and OKG AKTIEBOLAG - formed in 1980 the Nuclear Safety Board of the Swedish Utilities as a joint body for collaboration in safety matters. The Board participates in coordination of the safety work of the utilities and conducts its own safety projects, whereever this is more efficient than the utilities' working independently. The work of the Board shall contribute to optimizing safety in the operation of the Swedish nuclear power plants. The most important function of the Board is to collect, process and evaluate information on operational disturbances and incidents at Swedish and foreign nuclear power plants and then use the knowledge thus gained to improve the safety of the operation of the Swedish nuclear power plants (experience feedback). The work with Experience Feedback proceeds in three stages: Event follow-up, Fault analysis and Feedback of results. The Board runs a system for experience feedback (ERF). ERF is a computer-based information and communication system. ERF provides the Board with a daily update of operating experience in both Swedish and foreign nuclear power plants. Each Swedish nuclear power station supplies the ERF system with data on, among other things, operation and operational distrubances. Important experiences are thereby fed back to plant operation. Experience from foreign nuclear power stations can be of interest to the Swedish nuclear power plants. This information comes to RKS and is reviewed daily. The information that is considered relevant to Swedish plants is fed after analysis into the ERF system. Conversely, foreign nuclear power stations can obtain information from the operation of the Swedish plants. (author)

  11. EDF/EPRI collaborative program on operator reliability experiments

    International Nuclear Information System (INIS)

    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

  12. Experience from operating germanium detectors in GERDA

    Science.gov (United States)

    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.

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

    CERN Document Server

    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.

  14. First-year experience with the ATLAS online monitoring framework

    International Nuclear Information System (INIS)

    Corso-Radu, A

    2010-01-01

    ATLAS is one of the four experiments in the Large Hadron Collider (LHC) at CERN, which has been put in operation this year. The challenging experimental environment and the extreme detector complexity required development of a highly scalable distributed monitoring framework, which is currently being used to monitor the quality of the data being taken as well as operational conditions of the hardware and software elements of the detector, trigger and data acquisition systems. At the moment the ATLAS Trigger/DAQ system is distributed over more than 1000 computers, which is about one third of the final ATLAS size. At every minute of an ATLAS data taking session the monitoring framework serves several thousands physics events to monitoring data analysis applications, handles more than 4 million histograms updates coming from more than 4 thousands applications, executes 10 thousands advanced data quality checks for a subset of those histograms, displays histograms and results of these checks on several dozens of monitors installed in main and satellite ATLAS control rooms. This note presents the overview of the online monitoring software framework, and describes the experience, which was gained during an extensive commissioning period as well as at the first phase of LHC beam in September 2008. Performance results, obtained on the current ATLAS DAQ system will also be presented, showing that the performance of the framework is adequate for the final ATLAS system.

  15. Sixteen Years of International Co-operation. The OECD/NEA Co-operative Programme on Decommissioning

    International Nuclear Information System (INIS)

    Menon, S.; Valencia, L.

    2002-01-01

    The Co-operative Programme on Decommissioning under the administration of the Radioactive Waste Management Committee of the OECD Nuclear Energy Agency (NEA) has recently completed sixteen years of operation. The Programme, which is essentially an information exchange programme between decommissioning projects, came into being in 1985. It has grown from an initial 10 decommissioning projects from 7 countries to 39 projects from 14 countries today. From purely information exchange to start with, the Programme has, in later years, been functioning as a voice for the collective expression of views of the implementers of nuclear decommissioning. During the first sixteen years of the operation of the Co-operative Programme, nuclear decommissioning has grown from local specialist activities within projects to a competitive commercial industry. By the dismantling and release from regulatory control of over a dozen diverse nuclear facilities, the Programme has been able to demonstrate in practice, that nuclear decommissioning can be performed safely both for the workers and the public, and that this can be done at reasonable costs in an environmentally friendly fashion. During the recent years, discussions and work within the Co-operative Programme, specially within some of the Task Groups, have had/are having effects and repercussions not just in the field of nuclear decommissioning, but can possibly affect activities and regulations in other industries. This paper describes how the Programme and its activities and procedures have evolved over the years and indicate the directions of developments in the organization and execution of decommissioning projects. Finally, it gives a brief overview of the achievements of the Cooperative Programme and visualizes future developments in the field of nuclear decommissioning

  16. Duke staff tap into a fund of operating experience

    International Nuclear Information System (INIS)

    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)

  17. Operational experience with propulsion nuclear plants

    International Nuclear Information System (INIS)

    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)

  18. Biblis 1,300 MW unit B in operation for thirty years

    International Nuclear Information System (INIS)

    Lauer, H.

    2006-01-01

    Over the past thirty years, unit B of the Biblis nuclear power station has contributed towards safe, reliable and non-polluting electricity generation. Unit B was the first 1,300 MW unit in the world confirming the good experience accumulated in the construction and operation of plants this size. It laid the foundation for the advanced development of nuclear power plants up to the convoy line. The good availability this plant has achieved in its operating cycles proves the mature state of technology and the high level of qualification and motivation of the power plant staff and the personnel of external firms contracted to work for Biblis. Biblis B has served as a reference plant in German nuclear safety research, demonstrating that units this size can be operated safely. Unit B is also living proof of the possibility to raise nuclear power plants built in the seventies to the current state of the art by implementing the appropriate backfitting and modernization measures. Today, Biblis B is operated at a safety level clearly higher than that to be achieved for new plants internationally. This is also evident from comparison with the guiding values for the safety of new facilities as published by the International Atomic Energy Agency (IAEA). (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  20. Operation of the aircraft as a discipline of knowledge after 100 years of experience

    Directory of Open Access Journals (Sweden)

    Stanisław Danilecki

    2015-12-01

    Full Text Available The paper presents the course of the most important stages of development of the discipline related to the maintenance of aircrafts, as a synthesis of the 100-year experience. It is presented linking of technical maintenance of the aircraft with other disciplines of knowledge. The scope of technical maintenance was defined. The division and analysis of the methods for the maintenance was made. There were defined and discussed definitions used in the theory of maintenance, in conjunction with the construction of the aircraft and the tasks arising for constructor-manufacturer. MSG subsequent versions of the document constituting the logistical procedures for determining the programmable handling of civil airplanes were discussed.[b]Keywords[/b]: aviation, aircraft, maintenance aircrafts

  1. ONE HUNDRED YEARS OF MILES’ OPERATION- WHAT HAS CHANGED?

    Directory of Open Access Journals (Sweden)

    Vanja Pecić

    2008-12-01

    Full Text Available Lisfranc was probably the first to excise the rectum for cancer. He performed operation using perineal approach in 1826. This operation came into common use fifty years later. Czerny did the first combined abdominoperineal resection in attempt to finish excision he could not complete from below. Some fifteen years later Ernest Miles described the planned, one stage abdominoperineal resection.Miles name has become a synonym for this combined procedure, creating a radical change in the philosophy of resection and en bloc lymphadenectomy.In the beginning of twenty-century abdominoperineal resection became golden standard in the treatment of rectal cancer. Reconstructive operations, introduction of stapling devices and better understanding of potential tumor spread, reduced indications for Miles operation.Surgical treatment of rectal cancer made progress in the past 100 years. Miles was the first in line. Without his theory of perirectal lymphatic spread recurrence rate would be still as high as 95%.

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

    International Nuclear Information System (INIS)

    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

  3. Chemistry in water reactors: operating experience and new developments. 2 volumes

    International Nuclear Information System (INIS)

    1994-01-01

    These proceedings of the International conference on chemistry in water reactors (Operating experience and new developments), Volume 1, are divided into 8 sessions bearing on: (session 1) Primary coolant activity, corrosion products (5 conferences), (session 2) Dose reduction (4 conferences), (session 3) New developments (4 conferences), poster session: Primary coolant chemistry (16 posters), (session 4) Decontamination (5 conferences), poster session (2 posters), (session 5) BWR-Operating experience (3 conferences), (session 6) BWR-Modelling of operating experience (4 conferences), (session 7) BWR-Basic studies (4 conferences), (session 8) BWR-New technologies (3 conferences)

  4. Operational experience with the Daresbury accelerator tube

    International Nuclear Information System (INIS)

    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.)

  5. Experience in startup and operation of fast flux facility

    International Nuclear Information System (INIS)

    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

  6. Operational experience of the ATLAS accelerator

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  8. Design and operating experiences with 50MW steam generator

    International Nuclear Information System (INIS)

    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)

  9. Design and operating experiences with 50MW steam generator

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    International Nuclear Information System (INIS)

    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

  11. The future of the IPR-R1 TRIGA MARK I reactor after 48 years operation

    International Nuclear Information System (INIS)

    Maretti, Fausto Junior; Sette Camara, Luiz Otavio I.; Oliveira, Paulo Fernando

    2008-01-01

    The TRIGA Mark I IPR-R1 Reactor operates in the Nuclear Technology Development Center/ Brazilian Committion for Nuclear Energy (CDTN/CNEN), originally Institute of Radioactive Researches, in Belo Horizonte, Minas Gerais, since November 6, 1960. Initially it operated for isotope production for different uses, being later used in wide scale for another purposes as analyses for activation with neutrons and training of nuclear power plants operators. Dozens of degree theses were also developed with the use of the reactor. Along the years, several improvements were introduced in the reactor and its auxiliary systems, with the purpose to provide better use of the facilities and with the objective to increase the safety in the operation. The reactor is ready right now to operate at 250 kW, and for sure the nuclear applications programmed will be improved. The Operation Manual and the Safety Analysis report were already modified, as well as the Emergency Plan and the relative procedures to the same. After the tests at the end of 2008, the reactor will already be operating in the new power. This work presents a description of the several accomplishments of the last years and comments about the possibility of new uses for the reactor in the several areas of nuclear applications and some of the experiments and tests results during the upgrading program. (authors)

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

    Science.gov (United States)

    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

  13. Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach

    International Nuclear Information System (INIS)

    Mattson, G.E.

    1983-01-01

    As experiments continue to grow in size and complexity, a few technicians will no longer be able to maintain and operate the complete experiment. Specialization is becoming the norm. Subsystems are becoming very large and complex, requiring a great deal of experience and training for technicians to become qualified maintenance/operation personnel. Formal in-house and off-site programs supplement on-the-job training to fulfill the qualification criteria. This paper presents the Tandem Mirror Experiment-Upgrade (TMX-U) approach to manpower staffing, some problems encountered, possible improvements, and safety considerations for the successful operation of a large experimental facility

  14. Meckel's diverticulum in children: Our 12-year experience

    Directory of Open Access Journals (Sweden)

    Kamal Nain Rattan

    2016-01-01

    Full Text Available Background: Meckel's diverticulum (MD is the one of the most common congenital malformation of gastrointestinal tract and has varied clinical presentations. We are presenting here our 12-year experiences with MD in children at tertiary care hospital in North India. It highlights the fact that isolated gangrene of MD can occur, and it is associated with increased morbidity. Materials and Methods: This retrospective study is conducted by analysing the medical records of the patients who were operated for MD in the last 12 years in paediatric surgery department at our hospital. Results: Sixty-five patients were operated for MD in study period; in this 52 were males and 13 were females with mean age of presentation 3.2 years. The most common presentation was intestinal obstruction seen in 86.1% (56 cases. Intestinal haemorrhage was seen in 4.6% (3 cases and diverticulitis in 3% (2 cases. Perforation of the gut with peritonitis was present in 6.1% (four cases. Cause of obstruction was intussusception in 21.4% (12 cases, fibrous band connected to umbilicus in 17.8% (10 cases, volvulus in 17.8% (10 cases, kinking in 16.0% (9 cases, knotting in 14.2% (8 cases and herniation of gut below in 12.5% (7 cases. Isolated gangrene of MD was present in ten cases with intestinal obstruction. The ectopic gastric mucosa was seen in three and pancreatic mucosa in two cases. Mortality and morbidity during the study were one and three cases, respectively. Conclusion: MD may remain clinically silent for lifetime, or it may have life-threatening complications. In our series, intestinal obstruction and not the haemorrhage was the most common presentation. Isolated gangrene of MD with obstruction was present in significant numbers, which we failed to find in literature.

  15. ATLAS Strip Detector: Operational Experience and Run1-> Run2 Transition

    CERN Document Server

    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.

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

    International Nuclear Information System (INIS)

    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

  17. Operating experience of main steam isolation valves at Fessenheim and Bugey

    International Nuclear Information System (INIS)

    Dredemis, G.; Fourest, B.; Giroux, C.

    1985-07-01

    The paper presents the experience of Hopkinson MSIVs over about 40 reactor-years (1977 to 1984) of operation at Fessenheim and Bugey units (900 MWe PWR). The various problems encountered including ageing effects on auxiliary equipments and increases in closure time are discussed. The corrective actions undertaken by the utility and the safety assessment of these events performed by the french safety authorities are also described. This study is the synthesis of an in-depth analysis of Main Steam Isolation Valves (MSIV) and their auxiliary circuits equipping the Bugey and Fessenheim 900 MWe PWR nuclear power plants. These valves are different from those installed in the other French 900 MWe PWR reactors. The evaluation of the operation of these valves was made on the basis of incidents which occured during operation of the units or during the periodic tests, as well as anomalies discovered during maintenance operations. This analysis proved that the anomalies related to the design of the valves, as well as to their manufacture and installation, had been correctly dealt with. Furthermore, it should have also revealed potential anomalies due to ageing of the equipment

  18. Operating experience at CEBAF

    International Nuclear Information System (INIS)

    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

  19. Experience from operating germanium detectors in GERDA

    International Nuclear Information System (INIS)

    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)

  20. The University of Colorado OSO-8 spectrometer experiment. IV - Mission operations

    Science.gov (United States)

    Hansen, E. R.; Bruner, E. C., Jr.

    1979-01-01

    The remote operation of two high-resolution ultraviolet spectrometers on the OSO-8 satellite is discussed. Mission operations enabled scientific observers to plan observations based on current solar data, interact with the observing program using real- or near real-time data and commands, evaluate quick-look instrument data, and analyze the observations for publication. During routine operations, experiments were planned a day prior to their execution, and the data from these experiments received a day later. When a shorter turnaround was required, a real-time mode was available. Here, the real-time data and command links into the remote control center were used to evaluate experiment operation and make satellite pointing or instrument configuration changes with a 1-90 minute turnaround.

  1. Experience in operation and maintenance of systems of electrical generation by micro turbine: Transierra S.A.

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, Franz Miranda [TRANSIERRA S.A., Santa Cruz (Bolivia)

    2009-07-01

    This work tries to share the experience of throughout six years, turned into experience of operation and maintenance of micro turbines for generation electrical; same those are used in the stations of measurement of Transierra S.A. In the initial stage it would describe to the ways and characteristic operative qualities for each one of the Micro Turbines in each scene that differs throughout the four stations that the GASYRG composes, taking like game the analysis of the thermal efficiency. Next a particular description of happened events would be realized in the six translated years in faults of general and particular way, centering the attention to the analysis of the resources provided by the controllers of the equipment through registry of events. Analyses that finally would be translated in solutions to short and medium term obtaining operative continuity and provision of electrical energy indispensable for the systems of measurement and control of the stations. Finally a description of all the particular solutions and modifications that went giving problems of design which they were not contemplated by the manufacturer emanated of the necessity and shaped with the aid of the same knowledge of the equipment. (author)

  2. Sellafield - the achievements and lessons of 40 years experience

    International Nuclear Information System (INIS)

    Heafield, W.; Hexter, B.C.; Livesley, G.

    1996-01-01

    BNFL's operations, which support a global nuclear fuel cycle business and serve many companies in Pacific Basin countries, have been the subject of refinement from 40 years of experience. Many of the Company's operating philosophies are consistent with the principles of sustainable development. The paper acknowledges the important role that the nuclear industry can play in satisfying energy demands within economies of diminishing natural resources and societies which are becoming increasingly concerned about their impact on the environment. It explains how reprocessing can meet many of the criteria of sustainable development through recycling and the optimization of resources. It describes how BNFL have reduced the impact of its operations on the environment through the treatment of discharges and the minimization and stabilization of wastes requiring disposal. The establishment of BNFL Engineering Ltd as an outlet to the world markets for BNFL's engineering expertise and technology is covered. The paper looks at the responsible approach that BNFL is taking to liabilities management ensuring that no surprises are left for future generations. BNFL's commitment to the present and future of nuclear electricity generation is illustrated in the extent to which it is committed to making it operations safer and more cost effective through investment in research and development. The paper describes BNFL's commitment to the development of its employees and to the development of the communities in which it operates. The paper considers how BNFL has met its many challenges and draws out examples of sustainable development in practice. (author)

  3. Making the Most of the Operating Experience Feedback: Design of a Computerized Data Base Related to NPP Component Behavior

    International Nuclear Information System (INIS)

    Degrave, C.; Martin-Onraet, M.

    1998-01-01

    Electricite de France carries out several analyses on NPP component behavior every year. However, these analyses are conducted separately by specialists of only the kind of component and regardless of the time factor. Seven years ago, a working group from the Nuclear Operation Division completed a detailed examination of component behavior of the 50 NPP then in operation, over a ten-years period (from 1980 to 1990). These analyses have been centered on main components only. Today, another working group will integrate this operating experience in a computerized process to facilitate access to all the information contained in the data base. This system will be based on a site server allowing a user-friendly connection, and updated periodically. (author)

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

    International Nuclear Information System (INIS)

    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.

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

    Science.gov (United States)

    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.

  6. Canadian fuel development program and recent operational experience

    International Nuclear Information System (INIS)

    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)

  7. Study on application of operating experience to new nuclear power plant

    International Nuclear Information System (INIS)

    Hong, Nam Pyo

    1991-01-01

    From the standpoint of designing the nuclear power plant, nine operating units have been designed and constructed as turn-key base by foreign Nuclear Steam Supply System (NSSS) Suppliers or as component base by foreign Architect/Engineer companies. In case of the component base project, the owner of electric company generally has merits that owner's operational experiences can be effectively incorporated from the beginning stage of design by A/E. Even though six nuclear units, Kori Units 3 and 4, Yonggwang Units 1 and 2, and Ulchin Units 1 and 2, were designed as component base by foreign A/E's, operational experience feedback from Kori Unit 1, such as design improvement and system upgrade, could not be reflected, because the design process of the following units started well ahead before Kori Unit 1 operating experience is obtained enough to reflect on future nuclear power plant design. It can be stated that foreign A/E's used their experience in designing nuclear projects on very limited basis

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    International Nuclear Information System (INIS)

    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. Surgical treatment of chronic pancreatitis--a 14 years experience.

    Science.gov (United States)

    Stroescu, C; Dima, S; Scarlat, A; Ivanov, B; Bouaru, O; Ionescu, M; Vasilescu, C; Popescu, I

    2010-01-01

    Operative treatment of chronic pancreatitis is indicated for patients with intractable pain after failed medical and endoscopic treatment, or in the presence of complications of the disease. This study evaluates a single-center experience with operative management of chronic pancreatitis over a period of time of 14 years, regarding indication, surgical technique, early and late results. The records of 265 consecutive patients who underwent surgery for chronic pancreatitis between 1995 and 2008 were retrospectively reviewed and analyzed. Long-term outcomes were assessed by patient survey, with a median follow-up of 40 months. 265 patients underwent 275 operations for chronic pancreatitis with the main indication abdominal pain (46.8%), followed by suspected malignancy in 24.8% and recurrent episodes of acute pancreatitis in 18.6%. Resection procedures 54.5% (150), drainage procedures 1.09% (3), bypass and denervation procedures 44.36% (122) and exploratory laparotomy 3.27% (9) were performed with an overall morbidity of 22% and an in-hospital mortality rate of 2.64%. After a median follow-up of 40 months survival information was available for 137 patients (51.69%) with a 5-and actuarial survival rate of 74.7% and quality of life improvement in most patients, especially in the resected group. Our results suggest that in chronic pancreatitis the type of surgery has to be individualized in each patient (resection VS drainage) and organ preserving operations are safe and effective in providing long-term pain relief and in treating CP-related complications

  11. The Canadian CANDU fuel development program and recent fuel operating experience

    International Nuclear Information System (INIS)

    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 two-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 two 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)

  12. Operating experience feedback report: Experience with pump seals installed in reactor coolant pumps manufactured by Byron Jackson

    International Nuclear Information System (INIS)

    Bell, L.G.; O'Reilly, P.D.

    1992-09-01

    This report examines the reactor coolant pump (RCP) seal operating experience through August 1990 at plants with Byron Jackson (B-J) RCPs. ne operating experience examined in this analysis included a review of the practice of continuing operation with a degraded seal. Plants with B-J RCPs that have had relatively good experience with their RCP seals attribute this success to a combination of different factors, including: enhanced seal QA efforts, modified/new seal designs, improved maintenance procedures and training, attention to detail, improved seal operating procedures, knowledgeable personnel involved in seal maintenance and operation, reduction in frequency of transients that stress the seals, seal handling and installation equipment designed to the appropriate precision, and maintenance of a clean seal cooling water system. As more plants have implemented corrective measures such as these, the number of B-J RCP seal failures experienced has tended to decrease. This study included a review of the practice of continued operation with a degraded seal in the case of PWR plants with Byron Jackson reactor coolant pumps. Specific factors were identified which should be addressed in order to safety manage operation of a reactor coolant pump with indications of a degrading seal

  13. SAFARI-1: 30 years of operation

    International Nuclear Information System (INIS)

    D'Arcy, A.J.; Niebuhr, H.W.; Procter, G.I.

    1995-01-01

    SAFARI-1, a 20 MW tank-in-pool type MTR, was commissioned in 1965. It today enjoys some benefits from having operated for 17 years at a quarter of its design power. Ageing technology, non-availability of spares and wear and tear are, however, beginning to take their toll, while changing licensing requirements and shifting focus in its utilisation are at the same time compelling the AEC to invest capital in renovation, refurbishment, backfitting and upgrading in several different areas. A brief look at the operating history of SAFARI-1 is followed by a discussion of some of the more important upgrades recently carried out, focussing particular attention on a redesign of the Fail-Free Power System. (orig.)

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Post-operative delirium is associated with increased 5-year mortality.

    Science.gov (United States)

    Moskowitz, Eliza E; Overbey, Douglas M; Jones, Teresa S; Jones, Edward L; Arcomano, Todd R; Moore, John T; Robinson, Thomas N

    2017-12-01

    Post-operative delirium is associated with increased short term morbidity and mortality. Limited data exists on long term outcomes for older adults with postoperative delirium. We hypothesize that postoperative delirium is associated with increased 5-year mortality. Patients ≥50 years undergoing elective operations with planned intensive care unit (ICU) admissions were prospectively enrolled. The Confusion Assessment Method ICU (CAM-ICU) was used to diagnose delirium. The primary outcome variable was 5-year mortality. 172 patients were enrolled with an average age of 64 years. The overall incidence of delirium was 44% (75/172). At 5-years post-operatively, mortality was higher (59%, 41/70) in patients with delirium compared to patients without delirium (13%, 12/94, p delirium were 7.35 fold greater (95% CI: 1.49-36.18). Postoperative delirium is associated with increased long term mortality. Published by Elsevier Inc.

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

    International Nuclear Information System (INIS)

    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

  18. Fourteen-years experience with cochlear implantation in Ramathibodi Hospital.

    Science.gov (United States)

    Kasemsuwan, Lalida; Cheewaruangroj, Wichit; Tungkeeratichai, Jumroon; Bhongmakapat, Thongchai; Thawin, Cheamchit; Lertsukprasert, Krisna; Tiravanitchakul, Rattinan; Dara, Rada; Laothamatas, Jiraporn

    2010-12-01

    To review the cochlear implant program in Ramathibodi Hospital and share experience of cochlear implantation emphasized on clinical and surgical outcomes. Retrospective review of 143 ears (140 patients) operated with cochlear implant between 1995 and 2009. The demographic data including etiology of deafness and findings from temporal bone CTscans were reviewed. The authors' experience with cochlear implant surgery in terms of patient selection, patient advisory clinic, necessary equipment, pre- and postoperative evaluations, surgical techniques and complications were discussed. Most congenital origin was unknown etiology and congenital rubella was the most common known cause. From the CT scans of congenital deafness, vestibular aqueduct dilatation was the most common and found in 29.31% while Mondini malformation was shown to be 16.37%. The authors' surgical technique of using the pocket method and designed bony ridge at cortical mastoid rim had helped stabilizing the implant and electrode fancoil. During the last two years, no complication or revision surgery was detected. Cochlear implant surgery in both children and adults can result in good surgical outcome and fewer complications under experienced surgeons and a good team.

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

    International Nuclear Information System (INIS)

    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)

  20. Hydrogen-powered lawn mower: 14 years of operation

    International Nuclear Information System (INIS)

    Yvon, K.; Lorenzoni, J.-L.

    2006-01-01

    Our hydrogen-powered lawn mower [Yvon K, Lorenzoni J-L. Hydrogen powered lawn mower. Int J Hydrogen Energy 1993; 18, 345-48] has been operated without major interruption during the past 14 years. The commercial model was originally running on gasoline and was adapted to hydrogen by making small adjustments to the carburettor and by installing a hydrogen reservoir containing solid-state metal hydrides. During the evaluation period the only maintenance work was changing the lubricating oil of the engine once a year, and reactivating the metal hydride powder by external heating after an accidental inlet of air into the reservoir. There occurred no technical failure, and there was no safety incident, neither during operation nor during recharging of hydrogen. This demonstrates that a hydrogen-operated device of this type is mature for use by greater public. Cost and marketing issues are discussed. (author)

  1. ATLAS Pixel Detector Operational Experience

    CERN Document Server

    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...

  2. PROSPER guidelines: Guidelines for peer review and for plant self-assessment of operational experience feedback process

    International Nuclear Information System (INIS)

    2003-01-01

    Effective use of operational performance information is an important element in any plant operator's arrangements for enhancing the operational safety of a nuclear power plant (NPP). This has been recognized in the IAEA Safety Fundamental, The Safety of Nuclear Installations (Safety Series No. 110). Under the technical aspects of safety, one of the principles of operation and maintenance is that the operating organization and the regulatory body shall establish complementary programmes to analyse operating experience to ensure that lessons are learned and acted upon. Such experience shall be shared with relevant national and international bodies. The Convention on Nuclear Safety, which entered into force in July 1996, also recognized the importance of operational experience feedback as a tool of high importance for the safety of nuclear plant operation and its further enhancement. It follows that the arrangements and results achieved under the operation experience feedback process in Member States will be covered by the national report under the Convention and will be subject to periodical review. These principles are further expanded in the IAEA Safety Standards Safety of Nuclear Power Plants: Operation (Safety Standard Series No. NS-R-2, year 2000) under the Feedback of The IAEA-led Peer Review of the effectiveness of the Operational Safety Performance Experience Review process (PROSPER) and associated guidelines have been developed to provide advice and assistance to utilities or individual power plants to strengthen and enhance the effectiveness of operational experience programmes in achieving these fundamental objectives. The objectives of the former IAEA Assessment of Significant Safety Events Team (ASSET) service have been expanded to include an evaluation of the effective use of all operating performance information available to the plant (e.g. external operating experience, internal low-level and near miss event reports and other relevant operating

  3. Experiences of an operating association

    International Nuclear Information System (INIS)

    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

  4. Simulator experiments on operator reliability and training effectiveness

    International Nuclear Information System (INIS)

    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

  5. Industry use of operating experience to achieve improved nuclear plant safety

    International Nuclear Information System (INIS)

    Zebroski, E.L.

    1981-01-01

    A principal lesson drawn from the accident at Three Mile Island was the need for a comprehensive and rigorous system for analysis and feedback of operating experience to reactor operators. Chief executives of US utilities directed in mid-1979 that an intensive and rigorous system of analysis and feedback of operating experience be established. This system is commonly referred to as the ''Significant Events Program''. Since April 1980, the Nuclear Safety Analysis Center (NSAC) has been joined by the Institute for Nuclear Power Operations (INPO) in the field investigation of significant operating events. NSAC has responsibility for analysis of the design and physical events aspects, while INPO has primary responsibility for the operators' aspects, including procedures and training. The process of screening, analysis and feedback of operating experience is now functioning as a seven-step process. A variety of data sources is used, including License Event Reports and outage and major maintenance reports. These are compiled and indexed in convenient form. However, such data bases are used only as incidental tools for the basic investigations and analytical efforts. Rapid dissemination of results is provided by a computer-aided conferencing system, which links 70 operating LWR reactors in the USA, and which has now been extended to four utilities outside the USA, representing several dozen more reactors. Major safety and economic incentives are evident for the rigorous use of such operating experience and for participation in a comprehensive system. Traditional habits of secrecy are recognized as obstacles to timely communication. A principal responsibility of top management of reactor-operating organizations is to overcome such habits where they are counter to the public interest, as well as to the health and survival interest of the utility itself

  6. Operating experience with decommissioning of underground components, USA

    International Nuclear Information System (INIS)

    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

  7. Small sodium valve design and operating experience

    International Nuclear Information System (INIS)

    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.)

  8. Long-term operation experience with 2 ECR ion sources and planned extensions at HIT

    International Nuclear Information System (INIS)

    Winkelmann, T.; Cee, R.; Haberer, T.; Naas, B.; Peters, A.

    2012-01-01

    The HIT (Heidelberg Ion Beam Therapy Center) is the first treatment facility at a hospital in Europe where patients can be treated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. The operating time is 330 days per year, our experience after three years of continuous operation will be presented. In the future a helium beam for patient treatment is requested, therefore a third ion source will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line will be installed at a test-bench to commission and validate this section. Different test settings are foreseen to study helium operation as well as enhanced parameter sets for proton and carbon beams in combination with a modified beam transport line for higher transmission efficiency. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed. The paper is followed by the associated poster. (authors)

  9. Fermi Large Area Telescope Operations: Progress Over 4 Years

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, Robert A.; /SLAC

    2012-06-28

    The Fermi Gamma-ray Space Telescope was launched into orbit in June 2008, and is conducting a multi-year gamma-ray all-sky survey, using the main instrument on Fermi, the Large Area Telescope (LAT). Fermi began its science mission in August 2008, and has now been operating for almost 4 years. The SLAC National Accelerator Laboratory hosts the LAT Instrument Science Operations Center (ISOC), which supports the operation of the LAT in conjunction with the Mission Operations Center (MOC) and the Fermi Science Support Center (FSSC), both at NASA's Goddard Space Flight Center. The LAT has a continuous output data rate of about 1.5 Mbits per second, and data from the LAT are stored on Fermi and transmitted to the ground through TDRS and the MOC to the ISOC about 10 times per day. Several hundred computers at SLAC are used to process LAT data to perform event reconstruction, and gamma-ray photon data are subsequently delivered to the FSSC for public release with a few hours of being detected by the LAT. We summarize the current status of the LAT, and the evolution of the data processing and monitoring performed by the ISOC during the first 4 years of the Fermi mission, together with future plans for further changes to detected event data processing and instrument operations and monitoring.

  10. Operating Experience at the Aagesta Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Operating Experience at the Aagesta Nuclear Power Station

    International Nuclear Information System (INIS)

    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

  12. Operating Experience at the Aagesta Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Experience on implementation of the Integrated Safeguards approach for the MOX facility from the operator's point of view

    International Nuclear Information System (INIS)

    Nomi, Takayoshi; Nagatani, Taketeru; Ninagawa, Junichi; Nakajima, Shinji; Maruyama, Hajime; Asano, Takashi; Fujiwara, Shigeo

    2011-01-01

    The IS approach for the JNC-1 site was implemented in August 2008, and this was the first experience in the world. This IS approach aimed not only to improve efficiency and effectiveness of safeguards but also to reduce burden of the plant operation by improvement of efficiency of the inspection activity. It was planned to review effectiveness of this new approach after three years from implementation. And JAEA also evaluated effects by application of the IS approach for two MOX fuel facilities in the JNC-1 site based on the three years experiences from the operator's view point. As the result of evaluation, it was confirmed that there were some difference of benefits by application of the IS approach depending on features of the facility, automation level of equipment and advance level of safeguards systems. (author)

  14. Simulator experiments: effects of experience of senior reactor operators and of presence of a shift technical advisor on performance in a boiling water reactor control room

    International Nuclear Information System (INIS)

    Beare, A.N.; Dorris, R.E.; Gray, L.H.

    1984-12-01

    This report describes the first experiment in a Nuclear Regulatory Commission-sponsored program of training simulator experiments and field data collection to evaluate the effects of selected performance shaping factors on the performance of nuclear power plant control room operators. The factors investigated were the experience level of the Senior Reactor Operator (SRO) and the presence of a Shift Technical Advisor (STA). Data were collected from 16 two-man crews of licensed operators (one SRO and one RO). The crews were split into high and low SRO-experience groups on the basis of the years of experience of the SROs as SROs. One half (4 of the 8 crews in each group) of the high- and low-SRO experience groups were assisted by an STA or an SRO acting as an STA. The crews responded to four simulated plant casualties which ranged in severity from an uncomplicated turbine trip to an anticipated transient without scram (ATWS). No significant differences in overall performance were found between groups led by high (25 to 114 months licensed as an SRO) and low (1 to 17 months as an SRO) experience SROs. However, crews led by low experience SROs tended to have shorter task performance times than crews led by high experience SROs. Although a tendency for the STA-assisted groups to score higher on four of the five measures was observed, the presence of the STA had no statistically significant effect on overall team performance. The correlation between individual performance, as measured by four of the task performance measures, and experience, measured by months as a licensed operator, was not statistically significant, nor was the correlation between task performance and recency of simulator training. 18 references, 5 figures, 13 tables

  15. Recent operating experience and improvement of commercial IGCC

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Operating experience at Scottish Nuclear's power stations

    International Nuclear Information System (INIS)

    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)

  17. European clearinghouse on nuclear power plants operational experience feedback

    International Nuclear Information System (INIS)

    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.)

  18. Laparoscopic fundoplication for gastro-esophageal reflux disease: An 8 year experience

    Directory of Open Access Journals (Sweden)

    Balsara K

    2008-01-01

    Full Text Available Background :Laparoscopic fundoplication (LF has become the operation of choice for patients who need surgery for gastro esophageal reflux disease (GERD. Several studies have shown that the long-term results with surgery for GERD are better than medical therapy. In this retrospective study, we outline our experience with LF over an 8 year period. We analyzed factors that would affect the results of surgery and help in a better selection of patients for the operation. Materials and Methods :From 1999 to 2007, 107 patients underwent a LF. Eighty five patients had surgery for GERD and form the basis of this article. The other 22 patients had paraesophageal hernias and were excluded from the study. Pre-operative evaluation consisted of endoscopy, a barium study, esophageal manometry and 24h pH monitoring. Patients were followed up every 3rd month for the 1st year, twice in the 2nd year and then annually. Follow up was by personal interview or telephonic conversation. At the last follow up the results of surgery were graded as good or poor as per a scoring system. Those with a poor result were evaluated and re-operation advised when an anatomical problem caused the poor result. Subjective, objective and technical variables were analyzed which could affect the outcome of surgery. Results :In 84 patients, the operation was completed by laparoscopic access. One patient with bleeding was converted to open surgery. There were 5 intra-operative complications; 3 pnemothoracis, 1 esophageal perforation and 1 gastric fundus perforation. There was no mortality. Two patients underwent re-operation, 1 for delayed gastric emptying and 1 for dysphagia. Seventy four patients have been followed up from 7 months to 8 years. Eleven have been lost to follow up. Fifty seven patients (77% have had a good result from surgery. Seventeen (23% had a poor result; of these there were 4 wrap failures, 1 delayed gastric emptying and 1 excessive gas bloat as the cause. In 11

  19. Analysing the operative experience of basic surgical trainees in Ireland using a web-based logbook

    LENUS (Irish Health Repository)

    Lonergan, Peter E

    2011-09-25

    Abstract Background There is concern about the adequacy of operative exposure in surgical training programmes, in the context of changing work practices. We aimed to quantify the operative exposure of all trainees on the National Basic Surgical Training (BST) programme in Ireland and compare the results with arbitrary training targets. Methods Retrospective analysis of data obtained from a web-based logbook (http:\\/\\/www.elogbook.org) for all general surgery and orthopaedic training posts between July 2007 and June 2009. Results 104 trainees recorded 23,918 operations between two 6-month general surgery posts. The most common general surgery operation performed was simple skin excision with trainees performing an average of 19.7 (± 9.9) over the 2-year training programme. Trainees most frequently assisted with cholecystectomy with an average of 16.0 (± 11.0) per trainee. Comparison of trainee operative experience to arbitrary training targets found that 2-38% of trainees achieved the targets for 9 emergency index operations and 24-90% of trainees achieved the targets for 8 index elective operations. 72 trainees also completed a 6-month post in orthopaedics and recorded 7,551 operations. The most common orthopaedic operation that trainees performed was removal of metal, with an average of 2.90 (± 3.27) per trainee. The most common orthopaedic operation that trainees assisted with was total hip replacement, with an average of 10.46 (± 6.21) per trainee. Conclusions A centralised web-based logbook provides valuable data to analyse training programme performance. Analysis of logbooks raises concerns about operative experience at junior trainee level. The provision of adequate operative exposure for trainees should be a key performance indicator for training programmes.

  20. Application of operating experience in environmental qualification program

    International Nuclear Information System (INIS)

    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

  1. International Co-Operation in Control Engineering Education Using Online Experiments

    Science.gov (United States)

    Henry, Jim; Schaedel, Herbert M.

    2005-01-01

    This paper describes the international co-operation experience in teaching control engineering with laboratories being conducted remotely by students via the Internet. This paper describes how the students ran the experiments and their personal experiences with the laboratory. A tool for process identification and controller tuning based on…

  2. Evaluation of operating experience for early recognition of deteriorating safety performance

    International Nuclear Information System (INIS)

    Beckmerhagen, I.A.; Berg, H.P.

    2004-01-01

    One of the most difficult challenges facing nuclear power plants is to recognize the early signs of degrading safety performance before regulatory requirements are imposed or serious incidents or accidents occur. Today, the nuclear industry is striving for collecting more information on occurrences that could improve the operational safety performance. To achieve this, the reporting threshold has been lowered from incidents to anomalies with minor or no impact to safety. Industry experience (also outside nuclear industry) has shown that these are typical issues which should be considered when looking for such early warning signs. Therefore, it is important that nuclear power plant operators have the capability to trend, analyse and recognize early warning signs of deteriorating performance. It is necessary that plant operators are sensitive to these warning signs which may not be immediately evident. Reviewing operating experience is one of the main tasks for plant operators in their daily activities. Therefore, self assessment should be at the centre of any operational safety performance programme. One way of applying a self assessment program is through the following four basic elements: operational data, events, safety basis, and related experience. This approach will be described in the paper in more details. (authors)

  3. The Pajarito Site operating procedures for the Los Alamos Critical Experiments Facility

    International Nuclear Information System (INIS)

    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

  4. Blunt pediatric anterior and posterior urethral trauma: 32-year experience and outcomes.

    Science.gov (United States)

    Voelzke, Bryan B; Breyer, Benjamin N; McAninch, Jack W

    2012-06-01

    To analyze our experience with delayed repair of pediatric urethral trauma. From 1978 to 2007, 26 boys posterior urethral injuries were separately stratified. There were 8 anterior and 18 posterior urethral strictures. All patients presented in a delayed fashion. Mean follow up of the anterior cohort was 2.9 years. All repairs were performed via a ventral onlay buccal graft or anastomotic approach. The mean follow up of the posterior cohort was 1.1 years, and all posterior urethral injuries were repaired via an anastomotic approach. Overall success for anterior stricture disease was 88.9% and for posterior stricture disease was 89.5%. All three urethroplasty failures responded favorably to internal urethrotomy; however, one failed anterior repair and one of the two failed posterior repairs required two internal urethrotomy operations for success. No secondary urethroplasty operations were required and ultimately all patients were voiding per urethra without need for urethral dilation. Delayed, definitive repair of pediatric urethral trauma via open urethroplasty has a high success rate. Copyright © 2011 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

  5. Basic surgical training in Ireland: the impact of operative experience, training program allocation and mentorship on trainee satisfaction.

    LENUS (Irish Health Repository)

    O'Sullivan, K E

    2013-12-01

    Application to the Irish basic surgical training (BST) program in Ireland has decreased progressively over the past 5 years. We hypothesised that this decline was secondary to dissatisfaction with training correlated with reduced operative experience and lack of mentorship among BSTs.

  6. Isoe - information system on occupational exposure. Ten years of experience

    International Nuclear Information System (INIS)

    2002-01-01

    The information System on Occupational Exposure (ISOE) was created in 1992 to provide a forum for radiation protection experts from both utilities and national regulatory authorities to discuss, promote and co-ordinate international co-operative undertakings in the area of worker protection at nuclear power plants. The ISOE System is jointly managed by the OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA). This report provides an overview of the experience gained from, and benefits provided by, the ISOE System over the past ten years. Active participation of a large number of utilities in ISOE has contributed to a reduction in occupational exposure at nuclear power plants worldwide. (authors)

  7. U.S. Nuclear Power Plant Operating Cost and Experience Summaries

    International Nuclear Information System (INIS)

    Reid, RL

    2003-01-01

    The ''U.S. Nuclear Power Plant Operating Cost and Experience Summaries'' (NUREG/CR-6577, Supp. 2) report has been prepared to provide historical operating cost and experience information on U.S. commercial nuclear power plants during 2000-2001. Costs incurred after initial construction are characterized as annual production costs, which represent 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, operations 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 operating reports submitted by the licensees, the Nuclear Regulatory Commission (NRC) database for enforcement actions, and outage reports

  8. Development of new HRA methods based upon operational experience

    International Nuclear Information System (INIS)

    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)

  9. Operation experience with the 3 MW TRIGA Mark-II research reactor of Bangladesh

    International Nuclear Information System (INIS)

    Islam, M.S.; Haque, M.M.; Salam, M.A.; Rahman, M.M.; Khandokar, M.R.I.; Sardar, M.A.; Saha, P.K.; Haque, A.; Malek Sonar, M.A.; Uddin, M.M.; Hossain, S.M.S.; Zulquarnain, M.A.

    2004-01-01

    The 3 MW TRIGA Mark-II research reactor of Bangladesh Atomic Energy Commission (BAEC) has been operating since September 14, 1986. The reactor is used for radioisotope production ( 131 I, 99m Tc, 46 Sc), various R and D activities and manpower training. The reactor has been operated successfully since it's commissioning with the exception of a few reportable incidents. Of these, the decay tank leakage incident of 1997 is considered to be the most significant one. As a result of this incident, reactor operation at full power under forced-convection mode remained suspended for about 4 years. During that time, the reactor was operated at a power level of 250 kW so as to carry out experiments that require lower neutron flux. This was made possible by establishing a temporary by pass connection across the decay tank using local technology. The other incident was the contamination of the Dry Central Thimble (DCT) that took place in March 2002 when a pyrex vial containing 50 g of TeO 2 powder got melted inside the DCT. The vial was melted due to high heat generation on its surface while the reactor was operated for 8 hours at 3 MW for trial production of Iodine-131 ( 131 I). A Wet Central Thimble (WCT) was used to replace the damaged DCT in June 2002 such that the reactor operation could be resumed. The WCT was again replaced by a new DCT in June 2003 such that radioisotope production could be continued. A total of 873 irradiation requests (IRs) have been catered for different reactor uses. Out of these, 114 IRs were for radioisotope (RI) production and 759 IRs for different experiments. The total amount of RI produced stands at about 2100 GBq. The total amount of burn-up-fuel is about 6158 MWh. Efforts are on to undertake an ADP project so as to convert the analog console and I and C system of the reactor into digital one. The paper summarizes the reactor operation experiences focusing on troubleshooting, rectification, modification, RI production, various R and D

  10. Operation experience with the TRIGA reactor Wien 2004

    International Nuclear Information System (INIS)

    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)

  11. Precision operation of the Nova laser for fusion experiments

    International Nuclear Information System (INIS)

    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

  12. The NOνA experiment, the first 12 months of commissioning, operations and physics data

    Energy Technology Data Exchange (ETDEWEB)

    Norman, A. [Fermi National Accelerator Lab, Bativia, IL 60510 (France)

    2015-07-15

    The NOνA experiment is a long baseline neutrino experiment designed to make precision measurements of the oscillation probabilities for ν{sub µ} → ν{sub e} and ν{sub µ} → ν{sub µ} for both neutrinos and anti-neutrinos. These measurements will provide new information on the neutrino mass hierarchy, improve our knowledge of whether θ{sub 23} is non-maximal and possibility provide information on the CP violating phase δ{sub CP} of the PMNS neutrino mixing matrix. We present the observations of the first neutrino event in the NOνA far and near detectors along with data obtained during the first year of detector commissioning and operations. We use the data to demonstrate the detector’s ability to identify electron and muon neutrino events and to reject cosmic ray induced backgrounds at a level of 4 × 10{sup 7}:1. New estimates for the signal and background sensitivities of the NOνA experiment during the first year of full detector running are presented.

  13. Experiences in commissioning and in the first operating cycle of GKN-II

    International Nuclear Information System (INIS)

    Grauf, E.; Zaiss, W.; Tschannerl, J.

    1990-01-01

    In 1989, after only four and a half years of construction, the second unit of the Neckar Joint Nuclear Power Station (GKN-II) was commissioned as the third convoy type nuclear power plant. Its gross power of 1314 MWe makes the pressurized water reactor of GKN-II a unit in the highest power category so far of Siemens/KWU. Delivery to the operators ahead of schedule and observance of the budget are conclusive proof of the advantages of the convoy principle. In addition, GKN-II was able to benefit from the experience accumulated in the construction and commissioning of the two earlier convoy plants. This was reflected in the speedy completion, without major disturbances, of the warranty tests and the trial period of operation. It also has an impact on power operation, the first cycle of which showed the plant to have an availability of 100% throughout and is considered to be a full success by the operators. A special feature of GKN-II is the hybrid cooling tower ensuring that no heated cooling water is returned from the plant into the Neckar river. (orig.) [de

  14. Operating experience of steam generator test facility

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  17. Gain monitoring of telescope array photomultiplier cameras for the first 4 years of operation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, B.K., E-mail: bkshin@hanyang.ac.kr [Hanyang University, Seongdong-gu, Seoul (Korea, Republic of); Tokuno, H.; Tsunesada, Y. [Tokyo Institute of Technology, Meguro, Tokyo (Japan); Abu-Zayyad, T. [University of Utah, High Energy Astrophysics Institute, Salt Lake City, UT (United States); Aida, R. [University of Yamanashi, Interdisciplinary Graduate School of Medicine and Engineering, Kofu, Yamanashi (Japan); Allen, M.; Anderson, R. [University of Utah, High Energy Astrophysics Institute, Salt Lake City, UT (United States); Azuma, R. [Tokyo Institute of Technology, Meguro, Tokyo (Japan); Barcikowski, E.; Belz, J.W.; Bergman, D.R.; Blake, S.A.; Cady, R. [University of Utah, High Energy Astrophysics Institute, Salt Lake City, UT (United States); Cheon, B.G., E-mail: bgcheon@hanyang.ac.kr [Hanyang University, Seongdong-gu, Seoul (Korea, Republic of); Chiba, J. [Tokyo University of Science, Noda, Chiba (Japan); Chikawa, M. [Kinki University, Higashi Osaka, Osaka (Japan); Cho, E.J. [Hanyang University, Seongdong-gu, Seoul (Korea, Republic of); Cho, W.R. [Yonsei University, Seodaemun-gu, Seoul (Korea, Republic of); Fujii, H. [Institute of Particle and Nuclear Studies, KEK, Tsukuba, Ibaraki (Japan); Fujii, T. [Osaka City University, Osaka, Osaka (Japan); and others

    2014-12-21

    The stability of the gain of the photomultiplier (PMT) camera for the Fluorescence Detector (FD) of the Telescope Array experiment was monitored using an {sup 241}Am loaded scintillator pulsers (YAP) and a diffused xenon flasher (TXF) for a selected set of 35 PMT-readout channels. From the monitoring of YAP pulses over four years of FD operation, we found slow monotonic drifts of PMT gains at a rate of −1.7∼+1.7%/year. An average of the PMT gains over the 35 channels stayed nearly constant with a rate of change measured at −0.01±0.31(stat)±0.21(sys)%/year. No systematic decrease of the PMT gain caused by the night sky background was observed. Monitoring by the TXF also tracked the PMT gain drift of the YAP at 0.88±0.14(stat)%/year.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  20. Breeders: operational experience with fast power reactors in five states - more intensive German-French breeder cooperation

    International Nuclear Information System (INIS)

    Hueper, R.

    1978-01-01

    In the past year contracts have been signed and implemented for German-French cooperation in LMFBR development and commercialization. - The first German nuclear power station with a sodium cooled fast reactor, KNK II in Karlsruhe, is going into operation. - Construction of the prototype SNR 300 at Kalkar (Lower Rhine) is slowing down awaiting a decision of the German Federal Constitutional Court. - On the international level, remarkable experience in the operation of fast power reactors has accumulated. - Possible fuel cycle alternatives are being evaluated by an international committee. (orig.) [de

  1. The Drop Tower Bremen -Experiment Operation

    Science.gov (United States)

    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

  2. Staged air biomass gasification. Operation experiences and process optimisation. Final report; Trinopdelt forgasning. Erfaringsindhentning og optimering. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Houmann Jakobsen, H.; Kyster, L.

    2011-05-15

    The project's aim was to optimize the drying plant for wood chips, and to accumulate operating experience from the entire facility through a half year of operation. Based on theoretical considerations the potential for improving the drying process was evaluated. Possibilities to take into the flue gas humidity as a control parameter was studied, but after a few simple measurements it was concluded that the most relevant change was to seal of the plant to minimize the risk of ingress of cold air into the fuel. After finding the cause of the leaking a new fuel inlet to the dryer has been constructed, and the original, leaky rotary valve has been replaced. Both changes have led to a significant improvement of the drying plant. Operational experience from plant operation showed with clarity that the energy loss from charcoal in the ashes was significantly higher than desirable. The volume meant that the handling and disposal of charcoal in itself constituted a major operational cost. At the end of the project, promising experiments with incorporation of an extra step in the gasification process were carried out. It seems to be an effective method to convert the remaining carbon matter to flammable gas and increase gas generator efficiency. Work on reducing charcoal production now continues in a new project. (ln)

  3. World Nuclear University School of Uranium Production: Eight years' experience

    International Nuclear Information System (INIS)

    Trojacek, J.

    2014-01-01

    The World Nuclear University School of Uranium Production was established by DIAMO, state enterprise in 2006 year under the auspices of the World Nuclear University in London in partnership with international nuclear organizations – OECD/NEA and IAEA. Using the expertise and infrastructure of DIAMO State Enterprise, in conjuction with national and international universities, scientific institutions, regulatory authorities and other individual experts, the “school” covers its mission with the aim to provide world-class training on all aspects of uranium production cycle to equip operators, regulators and executives with the knowledge and expertise needed to provide expanded, environmentally-sound uranium mining throughout the world: • to educate students on all aspects of uranium production cycle including exploration, planning, development, operation, remediation and closure of uranium production facilities; • to improve the state of the art of uranium exploration, mining and mine remediation through research and development; • to provide a forum for the exchange of information on the latest uranium mining technologies and experiences – best practices.

  4. The Applied Meteorology Unit: Nineteen Years Successfully Transitioning Research into Operations for America's Space Program

    Science.gov (United States)

    Madura, John T.; Bauman, William H.; Merceret, Francis J.; Roeder, William P.; Brody, Frank C.; Hagemeyer, Bartlett C.

    2010-01-01

    The Applied Meteorology Unit (AMU) provides technology transition and technique development to improve operational weather support to the Space Shuttle and the entire American space program. The AMU is funded and managed by NASA and operated by a contractor that provides five meteorologists with a diverse mix of advanced degrees, operational experience, and associated skills including data processing, statistics, and the development of graphical user interfaces. The AMU's primary customers are the U.S. Air Force 45th Weather Squadron at Patrick Air Force Base, the National Weather Service Spaceflight Meteorology Group at NASA Johnson Space Center, and the National Weather Service Melbourne FL Forecast Office. The AMU has transitioned research into operations for nineteen years and worked on a wide range of topics, including new forecasting techniques for lightning probability, synoptic peak winds,.convective winds, and summer severe weather; satellite tools to predict anvil cloud trajectories and evaluate camera line of sight for Space Shuttle launch; optimized radar scan strategies; evaluated and implemented local numerical models; evaluated weather sensors; and many more. The AMU has completed 113 projects with 5 more scheduled to be completed by the end of 2010. During this rich history, the AMU and its customers have learned many lessons on how to effectively transition research into operations. Some of these lessons learned include collocating with the operational customer and periodically visiting geographically separated customers, operator submitted projects, consensus tasking process, use of operator primary advocates for each project, customer AMU liaisons with experience in both operations and research, flexibility in adapting the project plan based on lessons learned during the project, and incorporating training and other transition assistance into the project plans. Operator involvement has been critical to the AMU's remarkable success and many awards

  5. 18 years experience on UF{sub 6} handling at Japanese nuclear fuel manufacturer

    Energy Technology Data Exchange (ETDEWEB)

    Fujinaga, H.; Yamazaki, N.; Takebe, N. [Japan Nucelar Fuel Conversion Co., Ltd., Ibaraki (Japan)

    1991-12-31

    In the spring of 1991, a leading nuclear fuel manufacturing company in Japan, celebrated its 18th anniversary. Since 1973, the company has produced over 5000 metric ton of ceramic grade UO{sub 2} powder to supply to Japanese fabricators, without major accident/incident and especially with a successful safety record on UF{sub 6} handling. The company`s 18 years experience on nuclear fuel manufacturing reveals that key factors for the safe handling of UF{sub 6} are (1) installing adequate facilities, equipped with safety devices, (2) providing UF{sub 6} handling manuals and executing them strictly, and (3) repeating on and off the job training for operators. In this paper, equipment and the operation mode for UF{sub 6} processing at their facility are discussed.

  6. Review of operational experience with the gas-cooled Magnox reactors of the United Kingdom Central Electricity Generating Board

    International Nuclear Information System (INIS)

    Cave, L.; Clarke, A.W.

    1984-01-01

    The paper provides a review, which is mainly of a statistical nature, of 260 reactor years of operating experience which the (United Kingdom) Central Electricity Generating Board (CEGB) has obtained with its gas-cooled, graphite moderated Magnox reactors. The main emphasis in the review is on safety rather than on availability. Data are provided on the overall incidence and frequencies of faults and it is shown that the plant items which are predominantly responsible for recorded faults are the gas circulators and the turbo-alternators. Analysis of the reactor trip experience shows that the incidence of events which necessitate an automatic shutdown of the reactor has been about one per reactor year and that of other events leading to a reactor trip has not been much higher (1.4 per reactor year). As would be expected from the length of the operating experience, some relatively rare events have occurred (expected frequency 10 -2 per reactor year, or less) but on each occasion the reactor shutdown system and decay heat removal systems functioned satisfactorily. No overheating of, or damage to, the fuel occurred as a result of these rare events or of other, more frequent, faults. Analysis of the trend of failure rates has shown an improvement with time in nearly all safety-related items and external inspection of the primary coolant circuits has shown no significant deterioration with time. However, some derating of the reactors has been necessary to reduce the effects of oxidation of mild steel in CO 2 , in order to obtain optimum service lives. In spite of major differences between the systems, a comparison of the failure rates of analogous systems and plant items in PWRs and the Magnox reactors show a considerable similarity. Overall, the review of CEGB's operational experience with its Magnos reactors has shown that the frequencies of faults in systems and plant items has been satisfyingly low. (author)

  7. International Perspectives on the First-Year Experience in Higher Education. The First-Year Experience Monograph Series No. 52

    Science.gov (United States)

    Nutt, Diane, Ed.; Calderon, Denis, Ed.

    2009-01-01

    Students around the globe have unique first-year experiences but struggle with many of the same challenges. This monograph focuses on their journeys and provides insights for educators interested in learning about how institutions across the globe provide supports to students dealing with first-year transition issues. Based on the successful…

  8. Lessons Learned from Missing Flooding Barriers Operating Experience

    International Nuclear Information System (INIS)

    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

  9. The Elon Gap Experience: A Transformative First-Year Experience

    Science.gov (United States)

    Morrison, Stephen T.; Burr, Katherine H.; Waters, Rexford A.; Hall, Eric E.

    2016-01-01

    The Elon Gap Experience (EGE) was conceived out of Elon University's most recent strategic plan, the Elon Commitment (Elon University, 2009). One theme calls for "strategic and innovative pathways in undergraduate and graduate education," specifically "to launch a service program as part of a gap-year program" (Elon University,…

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

    International Nuclear Information System (INIS)

    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

  11. The Ross Procedure in Pediatric Patients: A 20-Year Experience of Ross Procedure in a Single Institution.

    Science.gov (United States)

    Yoon, Dong Woog; Yang, Ji-Hyuk; Jun, Tae-Gook; Park, Pyo Won

    2017-08-01

    The Ross/Ross-Konno procedure is considered a good option for irreparable aortic valve disease in pediatric patients because of its hemodynamic performance and potential for growth of the pulmonary autograft. This study is a review of the long-term results of our 20-year experience with the Ross and Ross-Konno operations in a single institution. Between June 1995 and January 2016, 16 consecutive patients (mean age, 6.0±5.9 years; range, 16 days to 17.4 years) underwent either a Ross operation (n=9) or a Ross-Konno operation (n=7). The study included 12 males and 4 females, with a median follow-up period of 47 months (range, 6 to 256 months). There were no cases of in-hospital or late mortality. Six reoperations were performed in 5 patients. Four patients underwent right ventricular-pulmonary artery (RV-PA) conduit replacement. Two patients underwent concomitant replacement of the pulmonary autograft and RV-PA conduit 10 years and 8 years after the Ross operation, respectively. The rate of freedom from adverse outcomes of the pulmonary autograft was 88% and 70% at 5 and 10 years, respectively. The rate of freedom from valve-related reoperations was 79% and 63% at 5 and 10 years, respectively. Pulmonary autografts demonstrated good durability with low mortality. The Ross/Ross-Konno procedure is a good option that can be performed safely in pediatric patients with aortic valve disease, even in a small-volume center.

  12. First years of operation of the LNS superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Rifuggiato, D.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rovelli, A. [Instituto Nazionale di Fisica Nucleare, Lab. Nazionali del Sud, Catania (Italy)

    1999-07-01

    The K800 Superconducting Cyclotron was commissioned in 1994 and has been in continuous operation since then. In 1996 many efforts were made to reach a condition of reliable operation. Several ion types have been accelerated and delivered to experimental halls. The demand for different beams has given the opportunity to explore several regions of the operating diagram of the machine: different magnetic field values have been set, as well as several RF frequencies have been used. The results demonstrate that the Cyclotron allows to accomplish a large variety of nuclear physics experiments, even if the maximum performance has not yet been achieved. A few sub-systems are being upgraded in view of the 'high intensity' operation (which is required for radioactive beam production) and in order to reach the maximum performance: upgrading is planned on the RF system and on the electrostatic deflectors. A new axial injection system has been designed to operate the machine in stand-alone mode. (authors)

  13. First years of operation of the LNS superconducting cyclotron

    International Nuclear Information System (INIS)

    Rifuggiato, D.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rovelli, A.

    1999-01-01

    The K800 Superconducting Cyclotron was commissioned in 1994 and has been in continuous operation since then. In 1996 many efforts were made to reach a condition of reliable operation. Several ion types have been accelerated and delivered to experimental halls. The demand for different beams has given the opportunity to explore several regions of the operating diagram of the machine: different magnetic field values have been set, as well as several RF frequencies have been used. The results demonstrate that the Cyclotron allows to accomplish a large variety of nuclear physics experiments, even if the maximum performance has not yet been achieved. A few sub-systems are being upgraded in view of the 'high intensity' operation (which is required for radioactive beam production) and in order to reach the maximum performance: upgrading is planned on the RF system and on the electrostatic deflectors. A new axial injection system has been designed to operate the machine in stand-alone mode. (authors)

  14. Operating experience with superconducting cavities at Jefferson Lab

    International Nuclear Information System (INIS)

    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

  15. Experiment operations plan for the MT-4 experiment in the NRU reactor

    International Nuclear Information System (INIS)

    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)

  16. Experiment on continuous operation of the Brazilian IEA-R1 research reactor

    International Nuclear Information System (INIS)

    Freitas Pintaud, M. de

    1994-01-01

    In order to increase the radioisotope production in the IEA-R1 research reactor at IPEN/CNEN-SP, it has been proposed a change in its operation regime from 8 hours per day and 5 days per week to continuous 48 hours per week. The necessary reactor parameters for this new operation regime were obtained through an experiment in which the reactor was for the first time operated in the new regime. This work presents the principal results from this experiment: xenon reactivity, new shutdown margins, and reactivity loss due to fuel burnup in the new operation regime. (author)

  17. Synthetic vision systems: operational considerations simulation experiment

    Science.gov (United States)

    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.

  18. Synthetic Vision Systems - Operational Considerations Simulation Experiment

    Science.gov (United States)

    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.

  19. Santa Maria de Garona: ten years of experience under commercial operation

    International Nuclear Information System (INIS)

    Sanchez, J.L.

    1981-10-01

    The problems encountered during the operation of this Spanish nuclear power plant are in the author's view similar to those in other counters. The great development in nuclear technology has not always been reflected in the applicable legislation. Also, the diversity of provisions on transport, the environment, public health etc. must be closely studied for correct application. The lengthy procedure for obtaining licences is also described as are problems of supply contracts with foreign firms. Finally, nuclear third party liability questions in the context of the Paris Convention and domestic regulations on transport are analysed in details. (NEA) [fr

  20. Operating experience with nuclear power stations in Member States in 1997

    International Nuclear Information System (INIS)

    1998-12-01

    This report is twenty-ninth in the IAEA series of annual reports on operating experience with nuclear power stations in Member States. The report is a direct output from the Agency's Power Reactor Information System (PRIS), whose database contains all operating experience data published in Agency's operating experience annual reports published since 1971 and basic information on power reactors, including design data. According to the information available to the Agency at the end of 1997, there were 437 nuclear power reactors having a total capacity of 351795 MW(e). During 1997 three new reactors having total capacity of 3555 MW(e) were connected to the grid in France and the Republic of Korea. There were 36 nuclear power plants under construction in the world. Load, operation and availability factors are used as the basic performance factors. In addition to annual performance data and outage information, the report contains a historical summary of performance and outages during the lifetime of individual plants and five figures illustrating worldwide performance and statistical data

  1. Operating Experience of Digital, Software-based Components Used in I and C and Electrical Systems in German NPPs

    International Nuclear Information System (INIS)

    Blum, Stefanie; Lochthofen, Andre; Quester, Claudia; Arians, Robert

    2015-01-01

    In recent years, many components in instrumentation and control (I and C) and electrical systems of nuclear power plants (NPPs) were replaced by digital, software-based components. Due to the more complex structure, software-based I and C and electrical components show the potential for new failure mechanisms and an increasing number of failure possibilities, including the potential for common cause failures. An evaluation of the operating experience of digital, software-based components may help to determine new failure modes of these components. In this paper, we give an overview over the results of the evaluation of the operating experience of digital, software-based components used in I and C and electrical systems in NPPs in Germany. (authors)

  2. Impact of the European Working Time Directive (EWTD) on the operative experience of surgery residents.

    Science.gov (United States)

    Hopmans, Cornelis J; den Hoed, Pieter T; van der Laan, Lijckle; van der Harst, Erwin; van der Elst, Maarten; Mannaerts, Guido H H; Dawson, Imro; Timman, Reinier; Wijnhoven, Bas P L; IJzermans, Jan N M

    2015-04-01

    In Europe and the United States, work hour restrictions are considered to be particularly burdensome for residents in surgery specialties. The aim of this study was to examine whether reduction of the work week to 48 hours resulting from the implementation of the European Working Time Directive has affected the operative experience of surgery residents. This study was conducted in a general surgery training region in the Netherlands, consisting of 1 university hospital and 6 district training hospitals. Operating records summarizing the surgical procedures performed as "primary surgeon" in the operating theater for different grades of surgeons were retrospectively analyzed for the period 2005-2012 by the use of linear regression models. Operative procedures performed by residents were considered the main outcome measure. In total, 235,357 operative procedures were performed, including 47,458 (20.2%) in the university hospital and 187,899 (79.8%) in the district training hospitals (n = 5). For residents in the university hospital, the mean number of operative procedures performed per 1.0 full-time equivalent increased from 128 operations in 2005 to 204 operations in 2012 (P = .001), whereas for residents in district training hospitals, no substantial differences were found over time. The mean (±SD) operative caseload of 64 residents who completed the 6-year training program between 2005 and 2012 was 1,391 ± 226 (range, 768-1856). A comparison of the operative caseload according to year of board-certification showed no difference. Implementation of the European Working Time Directive has not affected adversely the number of surgical procedures performed by residents within a general surgical training region in the Netherlands. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. The creation of SLAC leading to 30 years of operation

    International Nuclear Information System (INIS)

    Panofsky, W.K.H.

    1996-01-01

    The different phases of operation of SLAC which provided the basis of its longevity are outlined. SLAC has been an unusually productive laboratory both in terms of genuinely new revelations and the accumulation of archival data. Current operation of SLAC is divided between fixed target experiments, whose energy has now been extended to 50 GeV, and continued use of the SLC with the SLAC large detector. Because of the availability of polarization, results obtained in the SLC-SLD combination have been competitive with the experiments using LEP at CERN, notwithstanding the significantly larger available luminosities at the much larger LEP machine. In addition the SLC, together with specialized test facilities, constitute a basic laboratory to determine the design of the Next Linear Collider (NLC)

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

    International Nuclear Information System (INIS)

    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)

  5. The production control laboratories of the plutonium extraction Plant at Marcoule. Six years operating experience: 1957 - 1963

    International Nuclear Information System (INIS)

    Fontaine, A.

    1964-01-01

    In this paper, the author attempts to sum up the conditions prevailing, after six years of operation, in the Laboratories of the Plutonium Extraction Plant. The origins and objectives are briefly reviewed, the technology and staff recruitment policy are examined, and progress made is shown. The methods used as well as the scope of application and limits imposed at the present state are considered. Past achievements and further possibilities in the next future are examined. An attempt has been made to bring out the outlooks for the more distant future and to investigate the conditions required for the successful carrying out of the program. (author) [fr

  6. Decommissioning of nuclear reprocessing plants French past experience and approach to future large scale operations

    International Nuclear Information System (INIS)

    Jean Jacques, M.; Maurel, J.J.; Maillet, J.

    1994-01-01

    Over the years, France has built up significant experience in dismantling nuclear fuel reprocessing facilities or various types of units representative of a modern reprocessing plant. However, only small or medium scale operations have been carried out so far. To prepare the future decommissioning of large size industrial facilities such as UP1 (Marcoule) and UP2 (La Hague), new technologies must be developed to maximize waste recycling and optimize direct operations by operators, taking the integrated dose and cost aspects into account. The decommissioning and dismantling methodology comprises: a preparation phase for inventory, choice and installation of tools and arrangement of working areas, a dismantling phase with decontamination, and a final contamination control phase. Detailed description of dismantling operations of the MA Pu finishing facility (La Hague) and of the RM2 radio metallurgical laboratory (CEA-Fontenay-aux-Roses) are given as examples. (J.S.). 3 tabs

  7. Introduction of microsurgery in Vietnam by a charitable organization: a 15-year experience.

    Science.gov (United States)

    Merrell, J Craig; Tien, Nguyen Viet; Son, Nguyen Tai; An, Luu Ngoc; Sellers, Daniel; Russell, Robert; Manktelow, Ralph; Wei, Fu-Chan; Orgill, Dennis P

    2007-04-01

    Microsurgical procedures, although equipment- and labor-intensive, allow efficient treatment of selected soft-tissue, bone, and peripheral nerve defects. The precise surgical skills required and the high equipment and institutional costs have been deterrents to initiating programs in developing countries. The authors report their 15-year international effort in facilitating the development of microsurgical techniques in Vietnam. The authors reviewed their educational, logistical, and operative experience from 11 Operation Smile International missions to Vietnam and the microsurgical procedures performed independently by Vietnamese surgeons at the Central Military Hospital 108 in Hanoi. Over 15 years, Operation Smile International missions to Vietnam performed 108 free tissue transfer operations with 15 peripheral nerve transfer procedures and 143 nonmicrosurgical reconstructive operations. Visiting surgeons with specialized expertise taught facial reanimation, flap prefabrication, and perforator flaps. During this same period, Vietnamese surgeons became facile with microsurgical techniques and independently performed a wide array of these procedures in the institutions visited. Vietnamese surgeons have organized microsurgery divisions within some hospital departments and now teach microsurgical techniques. Repeated missions allowed for patient follow-up, staged procedures, educational exchange, and quality control. Several Vietnamese surgeons have traveled abroad to obtain additional training and have set up training programs in other areas of Vietnam. Charitable organizations can help surgeons in developing countries master complex microsurgical techniques through short-term medical missions, donation of equipment and supplies, and the encouragement of institutional support. A continuing education program, including local conferences, microsurgical laboratory training facilities, and study abroad, can aid this introduction.

  8. The importance for nuclear safety of efficient feedback of operational experience

    International Nuclear Information System (INIS)

    1987-09-01

    Experience of practical operation is a valuable source of information for improving and optimizing the safety and reliability of nuclear power plants. Therefore it is essential to collect information on abnormal events occurring at plants during operation and on all deviations from normal performance by systems and personnel that could be precursors of accidents. For this purpose it is necessary to establish hierarchical systems to feedback operational safety experience at utility, national and international levels and to make these systems as effective as possible. The present report attempts to identify the safety objectives of these systems, to analyse the difficulties presently encountered and to suggest possible improvements

  9. RB Research nuclear reactor, 30 years of operation; Istrazivacki nuclearni reaktor RB, povodom 30 godina rada

    Energy Technology Data Exchange (ETDEWEB)

    Pesic, M; Stefanovic, D [Boris Kidric Institute of nuclear sciences Vinca, Belgrade (Yugoslavia)

    1988-06-15

    Paper describes utilization, modifications and changes of construction and control-safety systems done at the RB reactor during 30 years of operation. Experiments performed at the reactor are summarized, new reactor equipment is described and the future plans are shown. Rad prikazuje eksploataciju reaktora RB tokom 30 godina rada, modifikacije i izmene u konstruktivnim i upravljacko-sigurnosnim sistemima. Sumirani su eksperimenti izvedeni na njemu, prikazana je nova oprema i planovi za buduci rad.

  10. Operation experience at the TRIGA Mark III reactor FRN within the last two years

    International Nuclear Information System (INIS)

    Rau, G.

    1976-01-01

    A survey is given of the history of FRN-reactor operation since the last TRIGA conference. In 1975, the reactor had been operated for 830 MWh and had been pulsed 1050 times. In the first half of 1976, an appreciable Increase of reactor activities took place. In this time interval, the integrated power amounted to 996 MWh and the number of released pulses to 1024. In 1975, an important event was the exchange of the defective rotary specimen rack against a water-operated type. For this purpose, the whole core had to be unloaded and the pool water had to be removed. In this connection, damages at the beam-port weldings had been discovered and had to be repaired immediately. In December 1975, a new core configuration had been set up by adding ten spare fuel elements into the F-resp. G-ring. The gain of excess reactivity amounted to approximately 1,8 $. This however allowed reactor operation without disturbance by Xe-poisoning only for a limited time interval. (author)

  11. Corrosion in PWR stainless steel components: a TSO perspective based on operating experience and expertises

    International Nuclear Information System (INIS)

    Curieres, I. de

    2015-01-01

    Stainless steels are used commonly in many circuits of a nuclear power plant. Particularly, they are the prime materials for the inside surface of the primary circuit. Their operating experience has been good, though a number of cases of degradations due to corrosion have been reported the last ten years. This number of events is increasing and many studies of damaged parts become available. Based on the operating experience and these studies, IRSN will provide its perspective on the safety-related issues associated with the corrosion of stainless steel components. It appears that today's knowledge is not sufficient to define relevant criteria or to determine the exact set of parameters which leads to SCC (Stress Corrosion Cracking) of stainless steels. As a consequence, the best strategy remains an inspection and repair/replacement one. Moreover many cases show the influence of pollutants in the SCC events. This emphasizes the fact that chemistry parameters are strongly connected to safety issues, with respect to the stainless steels integrity

  12. Best practices in the utilization and dissemination of operating experience at nuclear power plants

    International Nuclear Information System (INIS)

    2008-03-01

    IAEA Safety Standards Series No. SF-1 entitled Fundamental Safety Principles: Safety Fundamentals states the need for operating organizations to establish a programme for the collection and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, lessons learned are disseminated to the staff of the organization and to relevant national and international organizations, operating experience is utilized and corrective actions are effectively implemented. This publication has been developed to provide advice and assistance to nuclear installations and related institutions, including contractors and support organizations, to strengthen and enhance their own feedback process through the implementation of best practices in the utilization and dissemination of operating experience and to assess their effectiveness. Dissemination and utilization of internal and external operating experience is essential in supporting a proactive safety management approach of preventing events from occurring. Few new events reveal a completely new cause or failure mechanism. Although not recognized prior to the event, most subsequent investigations identify internal or external industry operating experience that, if applied effectively, would have prevented the event. Therefore, the establishment of an effective utilization and dissemination process is very beneficial in raising awareness of the organization and individuals of available operating experience, and focussing effort in the implementation of the lessons learnt. This leads to improved safety and reliability. The present publication is the outcome of a coordinated effort involving the participation of experts of nuclear organizations in several Member States. It was written to complement the publication IAEA Services Series No. 10 entitled PROSPER Guidelines - Guidelines for Peer Review and for Plant Self-assessment of

  13. Assessment of LWR piping design loading based on plant operating experience

    International Nuclear Information System (INIS)

    Svensson, P.O.

    1980-08-01

    The objective of this study has been to: (1) identify current Light Water Reactor (LWR) piping design load parameters, (2) identify significant actual LWR piping loads from plant operating experience, (3) perform a comparison of these two sets of data and determine the significance of any differences, and (4) make an evaluation of the load representation in current LWR piping design practice, in view of plant operating experience with respect to piping behavior and response to loading

  14. Operational Experience with the Frontier System in CMS

    International Nuclear Information System (INIS)

    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.

  15. Operational Experience with the Frontier System in CMS

    Science.gov (United States)

    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.

  16. Tritium Room Air Monitor Operating Experience Review

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Development Process and Technical Aspects of Laparoscopic Hepatectomy: Learning Curve Based on 15 Years of Experience.

    Science.gov (United States)

    Komatsu, Shohei; Scatton, Olivier; Goumard, Claire; Sepulveda, Ailton; Brustia, Raffaele; Perdigao, Fabiano; Soubrane, Olivier

    2017-05-01

    Laparoscopic hepatectomy continues to be a challenging operation associated with a steep learning curve. This study aimed to evaluate the learning process during 15 years of experience with laparoscopic hepatectomy and to identify approaches to standardization of this procedure. Prospectively collected data of 317 consecutive laparoscopic hepatectomies performed from January 2000 to December 2014 were reviewed retrospectively. The operative procedures were classified into 4 categories (minor hepatectomy, left lateral sectionectomy [LLS], left hepatectomy, and right hepatectomy), and indications were classified into 5 categories (benign-borderline tumor, living donor, metastatic liver tumor, biliary malignancy, and hepatocellular carcinoma). During the first 10 years, the procedures were limited mainly to minor hepatectomy and LLS, and the indications were limited to benign-borderline tumor and living donor. Implementation of major hepatectomy rapidly increased the proportion of malignant tumors, especially hepatocellular carcinoma, starting from 2011. Conversion rates decreased with experience for LLS (13.3% vs 3.4%; p = 0.054) and left hepatectomy (50.0% vs 15.0%; p = 0.012), but not for right hepatectomy (41.4% vs 35.7%; p = 0.661). Our 15-year experience clearly demonstrates the stepwise procedural evolution from LLS through left hepatectomy to right hepatectomy, as well as the trend in indications from benign-borderline tumor/living donor to malignant tumors. In contrast to LLS and left hepatectomy, a learning curve was not observed for right hepatectomy. The ongoing development process can contribute to faster standardization necessary for future advances in laparoscopic hepatectomy. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

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

    International Nuclear Information System (INIS)

    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

  19. IRS Guidelines: Joint IAEA/NEA International Reporting System for Operating Experience

    International Nuclear Information System (INIS)

    2010-01-01

    The International Reporting System for Operating Experience (IRS) is an international system jointly operated by the International Atomic Energy Agency (IAEA) and the OECD Nuclear Energy Agency (OECD/NEA). The fundamental objective of the IRS is to contribute to improving the safety of commercial nuclear power plants which are operated worldwide. This objective can be achieved by providing timely and detailed information on lessons learned from operating and construction experience at the international level. This information could be related to issues and events that are related to safety. The purpose of these guidelines is to describe the system and to give users the necessary background and guidance to enable them to produce IRS reports meeting a high standard of quality while retaining the effectiveness of the system expected by all Member States operating nuclear power plants. As this system is owned by the Member States, the IRS Guidelines have been developed and approved by the IRS National Co-ordinators with the assistance of both Secretariats (IAEA/NEA).

  20. Operational experience with Seibersdorf low-level incinerator

    International Nuclear Information System (INIS)

    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. Requirements and Possibilities for Operational Experience Feedback from the Plant's Manufacturer's Point of View

    International Nuclear Information System (INIS)

    Schimann, P.

    2010-01-01

    A large amount of nations has realized that nuclear energy can contribute sustainable to secure their national energy supply. In the last few years, apart from the established nuclear nations, other, often smaller countries have also decided for themselves to apply the nuclear option to secure their energy supply. This partly takes place in multi-national cooperation between neighboring countries on one side, as well as otherwise between different companies on the manufacturers'/utilities' side. The endeavor of building absolutely safe reactors and of operating them safely requires the necessity on different levels of considering existing and up to date experiences gained in all the nuclear projects' phases. The long time period of many years between the decision on building a nuclear power plant, the licensing procedure, the detailed planning, the construction phase and the commissioning of the plants, results in the necessity of having to incorporate the constant experience gain on all technical and administrative levels. This applies to the safety-related boundary conditions in the frame of a new-build project in the same way as for updating measures performed on existing plants. An often neglected fact, this also applies to the right choice of the guidelines to be applied, to an efficient and competent authority and utility body or to the integration of the appropriate technical specialists and experts. Therefore the utilities and their tasks are confronted with different requirements, depending on whether they are located in the country of responsible nuclear power plant utilities' head quarters or whether they are simply co-owners of a foreign plant. AREVA as company covering the complete nuclear cycle including the corresponding plant construction supports its partners in all project phases including the development of national institutions and knowledge transfer. All of AREVA's existing knowledge - even the recently obtained - is integrated directly in the

  2. Reviewing operational experience feedback

    International Nuclear Information System (INIS)

    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

  3. Operational experience with the Fermilab Linac

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  5. Operating Experience from Events Reported to the IAEA Incident Reporting System for Research Reactors

    International Nuclear Information System (INIS)

    2015-03-01

    Operating experience feedback is an effective mechanism in providing lessons learned from events and the associated corrective actions to prevent them, helping to improve safety at nuclear installations. The Incident Reporting System for Research Reactors (IRSRR), which is operated by the IAEA, is an important tool for international exchange of operating experience feedback for research reactors. The IRSRR reports contain information on events of safety significance with their root causes and lessons learned which help in reducing the occurrence of similar events at research reactors. To improve the effectiveness of the system, it is essential that national organizations demonstrate an appropriate interest for the timely reporting of events important to safety and share the information in the IRSRR database. At their biennial technical meetings, the IRSRR national coordinators recommended collecting the operating experience from the events reported to the IRSRR and disseminating it in an IAEA publication. This publication highlights the root causes, safety significance, lessons learned, corrective actions and the causal factors for the events reported to the IRSRR up to September 2014. The publication also contains relevant summary information on research reactor events from sources other than the IRSRR, operating experience feedback from the International Reporting System for Operating Experience considered relevant to research reactors, and a description of the elements of an operating experience programme as established by the IAEA safety standards. This publication will be of use to research reactor operating organizations, regulators and designers, and any other organizations or individuals involved in the safety of research reactors

  6. Evolution of Italian thermal power plants in the 2003-2008 period: evaluation of most important critical states and operative experiences

    International Nuclear Information System (INIS)

    Michi, L.; Camponeschi, A.

    2007-01-01

    The Italian thermal power plants park is characterized by a dept transformation that is significantly changing the technological mix. The main aspects of these developments and related issues were analyzed in the last two years of operating experience [it

  7. Operating experience with LAMPF main beam lines instrumentation and control system

    International Nuclear Information System (INIS)

    van Dyck, O.B.; Harvey, A.; Howard, H.H.; Roeder, D.L.

    1975-01-01

    Instrumentation and control (I and C) for the Los Alamos Clinton P. Anderson Meson Physics Facility (LAMPF) main beam line is based upon central computer control through remote stations which provide input and output to most devices. Operating experience shows that the ability of the computer to give high-quality graphical presentation of the measurements enhances operator performance and instrument usefulness. Experience also shows that operator efficiency degrades rapidly with increasing instrument response time, that is, with increasing delay between the time a control is changed and the result can be observed. For this reason, instrumentation upgrade includes speeding up data acquisition and display times to under 10 s. Similarly, television-viewed phosphors are being retained where possible since their instantaneous response is very useful. Other upgrading of the instrumentation system is planned to improve data accuracy, reliability, redundancy, and instrument radiation tolerance. Past experience is being applied in adding or relocating devices to simplify tuning procedures. (U.S.)

  8. Cardiac and great vessel injuries after chest trauma: our 10-year experience.

    Science.gov (United States)

    Onan, Burak; Demirhan, Recep; Öz, Kürşad; Onan, Ismihan Selen

    2011-09-01

    Cardiovascular injuries after trauma present with high mortality. The aim of the study was to present our experience in cardiac and great vessel injuries after chest trauma. During the 10-year period, 104 patients with cardiac (n=94) and great vessel (n=10) injuries presented to our hospital. The demographic data, mechanism of injury, location of injury, other associated injuries, timing of surgical intervention, surgical approach, and clinical outcome were reviewed. Eighty-eight (84.6%) males presented after chest trauma. The mean age of the patients was 32.5±8.2 years (range: 12-76). Penetrating injuries (62.5%) were the most common cause of trauma. Computed tomography was performed in most cases and echocardiography was used in some stable cases. Cardiac injuries mostly included the right ventricle (58.5%). Great vessel injuries involved the subclavian vein in 6, innominate vein in 1, vena cava in 1, and descending aorta in 2 patients. Early operations after admission to the emergency were performed in 75.9% of the patients. Thoracotomy was performed in 89.5% of the patients. Operative mortality was significantly high in penetrating injuries (p=0.01). Clinicians should suspect cardiac and great vessel trauma in every patient presenting to the emergency unit after chest trauma. Computed tomography and echocardiography are beneficial in the management of chest trauma. Operative timing depends on hemodynamic status, and a multidisciplinary team approach improves the patient's prognosis.

  9. Operational experience of ATLAS SCT and Pixel Detector

    CERN Document Server

    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.

  10. Analysis of operating experience of nuclear power plants

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  14. Risk management for operations of the Los Alamos critical experiments facility

    International Nuclear Information System (INIS)

    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 (SHEBA 2--Solution high-Energy Burst Assembly), two fast-spectrum benchmark assemblies (Flattop and Big Ten), and five general-purpose remote assembly machines which may be configured with nuclear materials and assembled by remote control. SNM 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 the same, 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

  15. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    International Nuclear Information System (INIS)

    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

  16. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. United States Department of Energy, Nevada Operations Office, completion report Operation KLAXON, Fiscal Year 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    The U.S. Department of Energy, Nevada Operations Office (DOE/NV), Completion Report provides a summary of activities conducted at the Nevada Test Site (NTS) between October 1, 1992, and September 30, 1993, associated with Operation KLAXON. (In the past, each annual Completion Report dealt with a series of underground nuclear detonations; however, because no nuclear tests were conducted during FY 1993, this Report summarizes continuing nonnuclear and nuclear test readiness activities at the NTS sponsored by DOE/NV.) The report serves as a reference for those involved with the planning and execution of Operation KLAXON and also serves as a planning guide for future operations. Information in the report covers the logistics and management of activities. Scientific information and data associated with NTS activities are presented in technical documents published by participating agencies. In September 1992, Congress legislated a nine-month moratorium on the testing of nuclear weapons. The bill also provided for a resumption of testing (with no more than five tests per year, or a total of 15 during the next three years) in July 1993, and mandated an end to nuclear testing, entirely, by 1996. President Bush signed the bill into law in October 1992.

  18. United States Department of Energy, Nevada Operations Office, completion report Operation KLAXON, Fiscal Year 1993

    International Nuclear Information System (INIS)

    1994-06-01

    The U.S. Department of Energy, Nevada Operations Office (DOE/NV), Completion Report provides a summary of activities conducted at the Nevada Test Site (NTS) between October 1, 1992, and September 30, 1993, associated with Operation KLAXON. (In the past, each annual Completion Report dealt with a series of underground nuclear detonations; however, because no nuclear tests were conducted during FY 1993, this Report summarizes continuing nonnuclear and nuclear test readiness activities at the NTS sponsored by DOE/NV.) The report serves as a reference for those involved with the planning and execution of Operation KLAXON and also serves as a planning guide for future operations. Information in the report covers the logistics and management of activities. Scientific information and data associated with NTS activities are presented in technical documents published by participating agencies. In September 1992, Congress legislated a nine-month moratorium on the testing of nuclear weapons. The bill also provided for a resumption of testing (with no more than five tests per year, or a total of 15 during the next three years) in July 1993, and mandated an end to nuclear testing, entirely, by 1996. President Bush signed the bill into law in October 1992

  19. The Chooz power station: ten years of operation

    International Nuclear Information System (INIS)

    Teste du Bailler, Andre

    1977-01-01

    The switching into actual service of the Chooz plant, the first pressurized water reactor ever built in France, occurred on 3rd april 1967. Ten years later, one can establish a highly positive balance schedule of plant's operation whose availability is satisfactory, except the mechanical failure which occurred during the startup. The behavior of the equipment, in particular of the components of the primary loop, was satisfactory in its whole since it allowed the gradual increase in capacity by 15% with respect to the initial design. It allowed also the achievment of noticeable progress in the design of equipment intended for the new power stations. Interesting results have also been obtained in radioprotection, working conditions of the staff and environment protection fields. Finally, the training of the operating teams has been closely followed, whether it concerned the operators directly affected by plant operation or the trainees gathered in a school specially organized for this purpose and transferred since to a training Center [fr

  20. STMI: several years of experience in nuclear plant dismantling

    International Nuclear Information System (INIS)

    Moreau, J.C.

    1985-01-01

    Since 1977, when STMI performed its first dismantling operation, the Company appreciably improved in that field through important operations: the dismantling of the calciothermy and fluoration metal Pu preparation facility, in La Hague reprocessing plant; the dismantling of the slag treatment chain, associated to calciothermy and fluoration processes, in La Hague reprocessing plant; and the cleaning of EL4 cell in Marcoule. To perform these operations, STMI's operating teams, on top of decontamination and dismantling technologies, strived to improve handling and transportation technologies, and to nuclearize many equipments. In order to increase its technical efficiency, STMI signed a cooperation agreement with FRAMATOME company. Therefore, the union between the operational know-hows of STMI and the design experience of TECHNICATOME allow the needs of any customs facing a dismantling case to be satisfied [fr

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

    International Nuclear Information System (INIS)

    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

  2. Operating experience of Fugen Nuclear Power Station

    International Nuclear Information System (INIS)

    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.)

  3. NUSTAR - The teenage years. Towards operation at FAIR

    Science.gov (United States)

    Herlert, Alexander

    2017-11-01

    The "NUclear STructure, Astrophysics and Reactions" (NUSTAR) Collaboration was formed at the end of 2003. More than ten years later, a good fraction of the envisaged experimental equipment has been successfully developed and constructed. While the NUSTAR community is looking forward to the start of the civil construction for the new FAIR facility, existing NUSTAR equipment is tested and operated at radioactive ion beam facilities worldwide. The status of the project is briefly described at the stage when it enters the teenage years.

  4. A 22-year Northern Irish experience of carotid body tumours.

    Science.gov (United States)

    O'Neill, Stephen; O'Donnell, Mark; Harkin, Denis; Loughrey, Maurice; Lee, Bernard; Blair, Paul

    2011-09-01

    Carotid body tumours (CBTs) are rare vascular neoplasms originating in paraganglionic cells of the carotid bifurcation. The aim of this study was to review all patients diagnosed with CBTs in Northern Ireland. A retrospective review was performed of all patients who had CBTs treated at our institutions between 1987 and 2009. Patient demographics, clinical symptomatology, investigative modality, therapeutic intervention, pathological analysis and long-term outcomes were assessed. Twenty-nine patients were identified with 33 CBTs and three glomus intravagale tumours (GITs). Six patients had bilateral CBTs (21%), one of whom had a synchronous GIT. Twenty-six patients underwent a total of 30 operative procedures for the resection of 28 CBTs and 3 GITs. Conventional operative treatment included subadventitial tumour excision. A vascular shunt facilitated arterial reconstruction following the removal of seven (23%) tumours and on six of these occasions (19%) continuity was restored with an interposition vein graft. For access the external carotid artery was ligated during the removal of four tumours (13%). Two tumours were considered malignant. No peri-operative mortalities were recorded. Immediate complications included peri-operative stroke secondary to an occluded vein graft (n=1), requirement of tracheostomy (n=2), emergency haematoma drainage (n=2) and transient cranial nerve damage (n=8). Late complications included pseudoaneurysm of vein graft with subsequent stoke (n=1), permanent cranial nerve damage (n=9), Horner's syndrome (n=1) and an asymptomatic vein graft occlusion (n=1). One patient had tumour recurrence two years post-operatively and died due to pulmonary metastases. Two other patients died of unrelated causes. All other patients remain well with no evidence of tumour recurrence at mean followup of 1801 days (range 159-9208 days). Our long-term experience is comparable with other reported case series where surgical intervention conferred a long

  5. Operation of CdZnTe Semiconductor Detectors in Liquid Scintillator for the COBRA Experiment

    International Nuclear Information System (INIS)

    Oldorf, Christian

    2015-08-01

    COBRA, the Cadmium-Zinc-Telluride O-neutrino double-Beta Research Apparatus, is an experiment aiming for the measurement of the neutrinoless double beta decay with several isotopes, in particular 116 Cd, 106 Cd and 130 Te. A highly granular large scale experiment with about 400 kg of CdZnTe semiconductor detectors is currently under development. To provide evidence for the neutrinoless double beta decay of 116 Cd, a background rate in the order of 10 -3 counts/keV/kg/a is needed to achieve the required half-life sensitivity of at least 2 . 10 26 years. To reach this target, the detectors have to be operated in a highly pure environment, shielded from external radiation. Liquid scintillator is a promising candidate as a circum fluent replacement for the currently used lacquer. Next to the function as highly pure passivation material, liquid scintillator also acts as a neutron shield and active veto for external gammas. Within this thesis, the design, construction and assembly of a test set-up is described. The operation of four CdZnTe detectors after several years of storage in liquid scintillator is demonstrated. Next to extensive material compatibility tests prior to the assembly, the commissioning of the set-up and the characterization of the detectors are shown. Finally, results concerning the background reduction capability of liquid scintillator and the detection of cosmic muons are presented and compared to a Monte Carlo simulation.

  6. Operation of the tokamak fusion test reactor tritium systems during initial tritium experiments

    International Nuclear Information System (INIS)

    Anderson, J.L.; Gentile, C.; Kalish, M.; Kamperschroer, J.; Kozub, T.; LaMarche, P.; Murray, H.; Nagy, A.; Raftopoulos, S.; Rossmassler, R.; Sissingh, R.; Swanson, J.; Tulipano, F.; Viola, M.; Voorhees, D.; Walters, R.T.

    1995-01-01

    The high power D-T experiments on the tokamak fusion test reactor (TFTR) at the Princeton Plasma Physics Laboratory commenced in November 1993. During initial operation of the tritium systems a number of start-up problems surfaced and had to be corrected. These were corrected through a series of system modifications and upgrades and by repair of failed or inadequate components. Even as these operational concerns were being addressed, the tritium systems continued to support D-T operations on the tokamak. During the first six months of D-T operations more than 107kCi of tritium were processed successfully by the tritium systems. D-T experiments conducted at TFTR during this period provided significant new data. Fusion power in excess of 9MW was achieved in May 1994. This paper describes some of the early start-up issues, and reports on the operation of the tritium system and the tritium tracking and accounting system during the early phase of TFTR D-T experiments. (orig.)

  7. Power-Cooling-Mismatch Test Series Test PCM-7. Experiment operating specifications

    International Nuclear Information System (INIS)

    Sparks, D.T.; Smith, R.H.; Stanley, C.J.

    1979-02-01

    The experiment operating specifications for the Power-Cooling-Mismatch (PCM) Test PCM-7 to be conducted in the Power Burst Facility are described. The PCM Test Series was designed on the basis of a parametric evaluation of fuel behavior response with cladding temperature, rod internal pressure, time in film boiling, and test rod power being the variable parameters. The test matrix, defined in the PCM Experiment Requirements Document (ERD), encompasses a wide range of situations extending from pre-CHF (critical heat flux) PCMs to long duration operation in stable film boiling leading to rod failure

  8. Applying operating experience to design the CANDU 3 process

    International Nuclear Information System (INIS)

    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

  9. Applying operating experience to design the CANDU 3 process

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    International Nuclear Information System (INIS)

    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)

  11. Glass melter materials technical options for the French vitrification process and operations experience authors

    International Nuclear Information System (INIS)

    Bonniaud, R.; Roznad, L.; Demay, R.

    1986-09-01

    The French vitrification process for solidifying high-level radioactive waste which has been under industrial application since 1978, is mentioned briefly. This technique involves glass melting at 1,150 deg.C, using an induction heated metallic vessel. The molten glass pouring is controlled by a thermal gate, which is also heated by induction. Two types of vessel are in use. Both are remotely removable and disposable to permit replacement at regular intervals. The technical criteria (the materials used have to meet) are described. The behaviour of the materials has been investigated using the industrial experience gained in the AVM facility during 8 years of operation, as well as with operation of a prototype for the new vitrification facilities under construction at La Hague. A short description of the use of these materials is also presented

  12. Operating experience of vault type dry storage and its relevance to future storage needs

    International Nuclear Information System (INIS)

    Maxwell, E.O.; Deacon, D.

    1982-01-01

    An outline description of the early passive cooled vault type dry stores for irradiated magnox fuel at the Wylfa Nuclear Power Station together with the valuable operating experience gained over many years. An outline description of the world's first air-cooled vault type dry store (350 Te) and comments on its construction and successful operation. A description of the basic principles that were used in the design of this store and how these principles have been developed for use on vault type storage systems for oxide fuel and vitrified waste. An examination of the basic parameters that the author's consider should be used to measure the adequacy of the many storage options currently being considered around the world is included in order that a better assessment of the various systems may be obtained

  13. Program of experiments for the operating phase of the Underground Research Laboratory

    International Nuclear Information System (INIS)

    Simmons, G.R.; Bilinsky, D.M.; Davison, C.C.; Gray, M.N.; Kjartanson, B.H.; Martin, C.D.; Peters, D.A.; Lang, P.A.

    1992-09-01

    The Underground Research Laboratory (URL) is one of the major research and development facilities that AECL Research has constructed in support of the Canadian Nuclear Fuel Waste Management Program. The URL is a unique geotechnical research facility constructed in previously undisturbed plutonic rock, which was well characterized before construction. The site evaluation and construction phases of the URL project have been completed and the operating phase is beginning. A program of operating phase experiments that address AECL's objectives for in situ testing has been selected. These experiments were subjected to an external peer review and a subsequent review by the URL Experiment Committee in 1989. The comments from the external peer review were incorporated into the experiment plans, and the revised experiments were accepted by the URL Experiment Committee. Summaries of both reviews are presented. The schedule for implementing the experiments and the quality assurance to be applied during implementation are also summarized. (Author) (9 refs., 11 figs.)

  14. CMS Data Transfer operations after the first years of LHC collisions

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    CMS experiment possesses distributed computing infrastructure and its performance heavily depends on the fast and smooth distribution of data between different CMS sites. Data must be transferred from the Tier-0 (CERN) to the Tier-1 for storing and archiving, and time and good quality are vital to avoid overflowing CERN storage buffers. At the same time, processed data has to be distributed from Tier-1 sites to all Tier-2 sites for physics analysis while MonteCarlo simulations synchronized back to Tier-1 sites for further archival. At the core of all transferring machinery is PhEDEx (Physics Experiment Data Export) data transfer system. It is very important to ensure reliable operation of the system, and the operational tasks comprise monitoring and debugging all transfer issues. Based on transfer quality information Site Readiness tool is used to create plans for resources utilization in the future. We review the operational procedures created to enforce reliable data delivery to CMS distributed sites all ov...

  15. [Laparoscopic adjustable gastric-banding treatment for morbid obesity our first year experience].

    Science.gov (United States)

    Iordache, N; Vizeteu, R; Iorgulescu, A; Zmeu, B; Iordache, M

    2003-01-01

    The authors present the results of a prospective study regarding their 1st year experience in laparoscopic adjustable gastric banding (LABG), which included 21 patients (5 males, 16 females), with an average age of 39 (between 20-53 years). The follow up was made at one and six months postoperative. The medium weight was 138 kg (between 95-172 kg), with a medium excess of body mass of 66.89 kg (extremes between 27.75 and 104 kg). The medium BMI (body mass index) was 48.9 (extremes: 34.5-66), 8 patients being superobese (BMI > 50). The average operating time was 120 min, all operations were finished laparosopically. Postoperative complications were: total disfagia (1 case), parietal suppuration (2 cases) and partial intragastric migration of the prosthesis (1 case). There were no deceased patients. The medium excess of body mass at 6 months after surgery was 46.57 (only 13 patients evaluated in this interval). After 6 months postoperative the comorbidities were healed at half of the patients. Although we do not benefit of a long time follow up, the favorable initial results permits us to state that LABG must find its place in the efforts of struggling against obesity and its consequences.

  16. Three Years of Experience of Wet Gas Allocation on Canyon Express

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Aditya; Hall, James; Letton, Winsor

    2005-07-01

    In September 2002, production was begun from the three fields that together form the Canyon Express System- King's Peak, Aconcagua, and Camden Hills. The 9 wells from these fields are connected to a pair of 12-inch flow lines carrying the commingled wet gas a distance of approximately 92 kilometers back to the Canyon Station platform for processing. At the 21st NSFMW in October 2003, an initial report was given on the status of Wet Gas Allocation for the Canyon Express project. As discussed in that paper, dual-differential, subsea wet gas meters were chosen for the task of allocating gas and liquids back to individual wells. However, since the gas from all three fields was very dry (Lockhart-Martinelli parameter less than 0.01) and because the operating pressures were quite high (250 bar), application of the dual-differential function of the meters yielded errors in both liquid and gas flow rates. Furthermore, as these problems were being uncovered, scale was beginning to collect inside some of the meters. Taken together, these problems produced system imbalances as great as 20%. To address the problems, one of the individual flow metering elements within each wet gas meter was chosen as the allocation meter, operating as a single-phase gas meter. After three years of operation of the Canyon Express Project, considerable experience has been accumulated. Since at the time it held the record for deep water hydrocarbon production, application of the technologies discussed here were challenging and required considerable flexibility. It is believed that the Canyon Express experiences will benefit future deep water flow metering projects. The knowledge acquired thus far is surveyed and summarized. The emphasis is on the technical aspects. (tk)

  17. Human Factors Engineering (HFE) insights for advanced reactors based upon operating experience

    International Nuclear Information System (INIS)

    Higgins, J.; Nasta, K.

    1997-01-01

    The NRC Human Factors Engineering Program Review Model (HFE PRM, NUREG-0711) was developed to support a design process review for advanced reactor design certification under 10CFR52. The HFE PRM defines ten fundamental elements of a human factors engineering program. An Operating Experience Review (OER) is one of these elements. The main purpose of an OER is to identify potential safety issues from operating plant experience and ensure that they are addressed in a new design. Broad-based experience reviews have typically been performed in the past by reactor designers. For the HFE PRM the intent is to have a more focussed OER that concentrates on HFE issues or experience that would be relevant to the human-system interface (HSI) design process for new advanced reactors. This document provides a detailed list of HFE-relevant operating experience pertinent to the HSI design process for advanced nuclear power plants. This document is intended to be used by NRC reviewers as part of the HFE PRM review process in determining the completeness of an OER performed by an applicant for advanced reactor design certification. 49 refs

  18. Review of electricity supply failures and plant improvements over 25 years operation of the Harwell materials test reactors

    International Nuclear Information System (INIS)

    Taylor, D.J.

    1986-01-01

    The evolution of the on-site electrical power sources is described, operational experience is reported and shortcomings are identified. Disturbances in the external power supplies to the reactors are listed for the past 25 years and failure probabilities are derived from this historical data. The 132 kV overhead supply to the Harwell site is identified as the source of nearly 90% of the disturbances. (author)

  19. Review of electricity supply failures and plant improvements over 25 years operation of the Harwell materials test reactors

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, D. J. [UKAEA Harwell (United Kingdom)

    1986-02-15

    The evolution of the on-site electrical power sources is described, operational experience is reported and shortcomings are identified. Disturbances in the external power supplies to the reactors are listed for the past 25 years and failure probabilities are derived from this historical data. The 132 kV overhead supply to the Harwell site is identified as the source of nearly 90% of the disturbances. (author)

  20. Contributions of the European Operating Experience Feedback Project to Support Regulatory Bodies

    International Nuclear Information System (INIS)

    Heitsch, M.

    2016-01-01

    Operating Experience Feedback (OEF) is one of the ways of improving the nuclear safety of operating nuclear power plants. The EC-Clearinghouse initiative was set up in 2008 to support nuclear regulatory authorities of EU Member States, but also Technical Support Organizations, international organizations and the broader nuclear community, to enhance nuclear safety. The differing regulatory regimes in the EU member countries and a significant diversity of the nuclear power plant (NPP) designs have been a challenge in the establishment of the European Clearinghouse. The European Clearinghouse is organized as a Network operated by a Central Office located at the Institute for Energy and Transport (IET) which is part of Joint Research Centre (JRC) of the European Commission. It gathers 17 European regulatory authorities and 3 major European Technical Support organizations (TSO). The Clearinghouse aims at providing lessons learned, recommendations and best practices from operational experience of NPPs based on support and commitment from the EU nuclear regulatory authorities. One of the objectives of the European Clearinghouse is to establish European best practices for the assessment of unusual events in NPPs. The paper will present the main activities of the European Clearinghouse. These include: • Topical studies providing in-depth assessment of selected topics important for the safe operation of NPPs. Statistical tools help to identify interesting subjects for these studies; • Quarterly reports on operating experience; • Training courses in the field of root cause analysis and event investigation; • Development, maintenance and population of a database for storage of operating experience related information; • Collaboration with international organizations such as IAEA and OECD/NEA on all aspects of OEF. All activities of the Clearinghouse initiative focus on providing an added value for nuclear regulation. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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.

  3. Operational plans for life science payloads - From experiment selection through postflight reporting

    Science.gov (United States)

    Mccollum, G. W.; Nelson, W. G.; Wells, G. W.

    1976-01-01

    Key features of operational plans developed in a study of the Space Shuttle era life science payloads program are presented. The data describes the overall acquisition, staging, and integration of payload elements, as well as program implementation methods and mission support requirements. Five configurations were selected as representative payloads: (a) carry-on laboratories - medical emphasis experiments, (b) mini-laboratories - medical/biology experiments, (c) seven-day dedicated laboratories - medical/biology experiments, (d) 30-day dedicated laboratories - Regenerative Life Support Evaluation (RLSE) with selected life science experiments, and (e) Biomedical Experiments Scientific Satellite (BESS) - extended duration primate (Type I) and small vertebrate (Type II) missions. The recommended operational methods described in the paper are compared to the fundamental data which has been developed in the life science Spacelab Mission Simulation (SMS) test series. Areas assessed include crew training, experiment development and integration, testing, data-dissemination, organization interfaces, and principal investigator working relationships.

  4. Experiment Operating Specification for the Semiscale MOD-2C feedwater and steam line break experiment series. Appendix S-FS-6 and 7

    International Nuclear Information System (INIS)

    Boucher, T.J.; Owca, W.A.

    1985-05-01

    This document is the Semiscale MOD-2C feedwater and steam line break experiment series Experiment Operating Specification Appendix for tests S-FS-6 and S-FS-7. Test S-FS-6 is the third test in the series and simulates a 100% break in a steam generator bottom feedwater line downstream of the check valve accompanied by compounding factors (such as check valve failure, loss-of-offsite power at SIS and SIS delayed until low steam generator pressure signal). The test is terminated after plant stabilization and recovery procedures including unaffected loop steam and feed, pressurizer heater operation, pressurizer auxiliary spray operation, and normal charging/letdown operation. Test S-FS-7 is the fourth test in the series and simulates a 14.3% break in a steam generator bottom feedwater line downstream of the check valve, accompanied by compounding factors. The test is terminated after plant stabilization procedures including unaffected loop steam and feed, pressurizer heater operation, and normal charging/letdown operation. The test was followed by an affected loop secondary refill after isolating the break. The Appendix contains information on the major fluid systems, initial experiment conditions, experiment boundary conditions, and sequence of experiment events. Also included is a discussion of the scaling criteria and philosophy used to develop the experiment initial and boundary conditions and system configuration

  5. The Component Operational Experience Degradation and Ageing Program (CODAP). Review and lessons learned (2011-2014)

    International Nuclear Information System (INIS)

    Dragea, Tudor; Riznic, Jovica R.

    2015-01-01

    The structural integrity of piping systems is crucial to continuous and safe operation of nuclear power plants. Across all designs, the pressure boundary and its related piping and components, form one of the many levels of defense in the continuous and safe operation of a nuclear power plant. It is therefore necessary to identify, understand, evaluate and catalogue all of the various degradation mechanisms and failures that affect various piping systems and components across all nuclear power plants (NPP's). This need was first recognized in 1994 by the Swedish Nuclear Power Inspectorate (SKI) which launched a five-year Research and Development (R and D) project to explore the viability of creating an international pipe failure database (SKI-PIPE) (Riznic, 2007). The project was considered to be very successful and in 2002, the Organization for Economic Co-operation and Development (OECD) Pipe Failure Data Exchange (OPDE) was created. OPDE was operated under the umbrella of the OECD Nuclear Energy Agency (NEA) and was created in order to produce an international database on the piping service experience applicable to commercial nuclear power plants. After the successful completion of OPDE, the OECD, as well as other international members, agreed to participate in OPDE's successor: the Component Operational Experience Degradation and Ageing Program (CODAP). The objective of CODAP is to collect information on all possible events related to the failure and degradation of passive metallic components in NPP's. With CODAP winding down to the completion of its first phase in December 2014, this report will focus on the conclusions and the lessons learned throughout the many years of CODAP's implementation. There are currently 14 countries participating in CODAP, many of whom are industry leaders (France, Canada, U.S.A., Germany, Japan, Korea etc.). This cooperation on an international scale provides a library of OPerational EXperience (OPEX) for all participating NPP

  6. Annual report of operation management in nuclear power stations, fiscal year 1985

    International Nuclear Information System (INIS)

    1986-09-01

    Twenty years have elapsed since the first practical nuclear reactor in Japan started the operation. In the generated power in fiscal year 1985, that of nuclear power stations for the first time overtook that of thermal power stations, and now the age of nuclear power as the main and oil power as the subordinate has begun. As of the end of fiscal year 1985, there were 32 nuclear power plants in operation, having total output capacity of 24.521 million kW. In fiscal year 1985, nuclear power plants generated about 159 billion kWh, which is about 26 % of electric power supply. As to the capacity factor, 76 % was attained in fiscal year 1985, and this is ranked in the top group of LWR-operating countries in the world. It showed that the Japanese technology of nuclear power generation is at the top level in the world. However, in order to increase nuclear power generation and to accomplish the role of main electric power source hereafter, it is necessary to further increase the reliability and economical efficiency. The list of nuclear power stations in Japan, the state of operation of nuclear power stations, the state of accidents and troubles, the state of regular inspection, the management of radioactive wastes and the radiation exposure of workers in nuclear power stations, the operational management and others are reported. (Kako, I.)

  7. Operational Experience with the ATLAS Pixel Detector

    CERN Document Server

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Operational experience of the upgraded LHC injection kicker magnets during Run 2 and future plans

    Science.gov (United States)

    Barnes, M. J.; Adraktas, A.; Bregliozzi, G.; Goddard, B.; Ducimetière, L.; Salvant, B.; Sestak, J.; Vega Cid, L.; Weterings, W.; Vallgren, C. Yin

    2017-07-01

    During Run 1 of the LHC, one of the injection kicker magnets caused occasional operational delays due to beam induced heating with high bunch intensity and short bunch lengths. In addition, there were also sporadic issues with vacuum activity and electrical flashover of the injection kickers. An extensive program of studies was launched and significant upgrades were carried out during Long Shutdown 1 (LS 1). These upgrades included a new design of beam screen to reduce both beam coupling impedance of the kicker magnet and the electric field associated with the screen conductors, hence decreasing the probability of electrical breakdown in this region. This paper presents operational experience of the injection kicker magnets during the first years of Run 2 of the LHC, including a discussion of faults and kicker magnet issues that limited LHC operation. In addition, in light of these issues, plans for further upgrades are briefly discussed.

  10. Operating experience with a VMEbus multiprocessor system for data acquisition and reduction in nuclear physics

    International Nuclear Information System (INIS)

    Kutt, P.H.; Balamuth, D.P.

    1989-01-01

    A multiprocessor system based on commercially available VMEbus components has been developed for the acquisition and reduction of event-mode data in nuclear physics experiments. The system contains seven 68000 CPU's and 14 MB of memory. A minimal operating system handles data transfer and task allocation, and a compiler for a specially designed event analysis language produces code for the processors. The system has been in operation for four years at the University of Pennsylvania Tandem Accelerator Laboratory. Computation rates over 3 times that of a MicroVAX II have been achieved at a fraction of the cost. The use of WORM optical disks for event recording allows the processing for gigabyte data sets without operator intervention. A more powerful system is being planned which will make use of recently developed RISC processors to obtain an order of magnitude increase in computing power per node

  11. Operating Experiences of a Loss of Voltage Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    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. The first Italian superconducting fault current limiter: Results of the field testing experience after one year operation

    International Nuclear Information System (INIS)

    Martini, L; Bocchi, M; Ascade, M; Valzasina, A; Rossi, V; Angeli, G; Ravetta, C

    2014-01-01

    Ricerca sul Sistema Energetico S.p.A. (RSE) has been gaining a relevant experience in the simulation, design and installation of resistive-type Superconducting Fault Current Limiter (SFCL) devices for more than five years in the framework of a R and D national project funded by the Ricerca di Sistema (RdS). The most recent outcome of this research activity is the installation of a resistive-type BSCCO-based 9 kV / 3.4 MVA SFCL device in a single feeder branch of the Medium Voltage (MV) distribution network managed by A2A Reti Elettriche S.p.A (A2A) in the Milano area. This installation represents the first SFCL successfully installed in Italy. In this paper, we report on the main outcomes after a more than 1-year long steady-state field testing activity. The design of an upgraded device to be installed in the same substation has already been initiated: the new SFCL will allow to protect four different feeders, therefore implying a device upgrade up to 15.6 MVA.

  13. Two 850 MW turbines on daily cycling, design and operating experience

    Energy Technology Data Exchange (ETDEWEB)

    Stodieck, W; Straetz, A [Maschinenfabrik Augsburg-Nuernberg (M.A.N.) A.G., Nuernberg (Germany, F.R.)

    1979-02-01

    When Pennsylvania Power and Light Company (PPandL) of Allentown, U.S.A. signed a contract in 1970 with M.A.N. for the supply of two 850 MW turbines as part of extension of its existing coal-fired power station at Martins Creek by two oil-fired units, continuous base load operation was planned for the initial years. After about ten years both units should have been curbed to low load operation at night and completely shutdown at weekends. Then in 1973 when the oil crisis led to fuel prices which proved the operation of both units uneconomic the way they were planned for the initial years, all conditions were given to operate both turbines on a daily cycling basis from their commissioning day on. This was due to the installation of quality equipment for the improvement of thermal performance.

  14. Operating experience with the Fermilab 500-GeV accelerator

    International Nuclear Information System (INIS)

    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

  15. Best Practices in the Management of an Operating Experience Programme at Nuclear Power Plants

    International Nuclear Information System (INIS)

    2010-08-01

    The IAEA Fundamental Safety Principles (IAEA Safety Standards Series No. SF-1) state the need for operating organizations to establish a programme for the feedback and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, lessons learned are disseminated to the staff of the organization and to the relevant national and international organizations and corrective actions are effectively implemented. In IAEA Operational Safety Review Team (OSART) and Peer Review of the effectiveness of the Operational Safety Performance Experience Review (PROSPER) missions, weaknesses in the management of operating experience (OE) programmes have been identified as one of the root causes of the recurrence of events. This publication has been developed to provide advice and assistance to nuclear installation managers and related institutions, including contractors and support organizations, to strengthen and enhance the management of their OE processes. In this publication, a number of barriers to the successful management of an OE programme have been identified. Managers are encouraged to review and evaluate these barriers with a view to identifying and eliminating them within their own organizations

  16. Selection of operations staff, qualifications and experience

    International Nuclear Information System (INIS)

    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

  17. Operating years 1993 through 1995 power purchases

    International Nuclear Information System (INIS)

    1991-12-01

    Bonneville Power Administration (BPA) is obligated to supply electric power to its contractual customers. Based on a forecast of growing customer loads and assuming Critical Period water conditions in the Columbia River Basin, BPA is planning to meet a firm energy deficit during the four operating years (OY) 1992 through 1995, i.e., August 1991 through July 1995. BPA has executed several power purchase agreements to cover the projected OY 1992 deficit. The proposed action is to extend two existing one-year power purchase agreements for an additional three years to cover the four-year Critical Period energy deficit. The extension of these two one-year power purchase agreements would: (1) increase BPA's firm energy load-carrying capability; (2) allow BPA to meet its firm energy contractual commitments over the remaining three years of the four-year Critical Period from August 1, 1992, to July 31, 1995; (3) provide flexibility for BPA's use of hydroelectric resources over the Critical Period; and (4) increase system reliability. Under Critical Period water conditions, absent the proposed action, projected loads would exceed the capability of the Federal power system to serve those loads. The purpose of BPA's proposed action is to assure consistency with its statutory responsibilities, including those found in the Pacific Northwest Electric Power Planning and Conservation Act (Northwest Power Act)

  18. Experience from the construction and operation of Tarapur and Rajasthan Nuclear Power Stations

    International Nuclear Information System (INIS)

    Shah, J.C.; Pardiwala, T.F.; Kothare, V.V.; Rao, M.H.P.; Nanjundeswaran, K.

    1977-01-01

    India's experience in construction and operation of nuclear power stations so far covers two BWR and four PHWR Units in three power stations. Two more PHWR units are at an early stage of construction. The twin unit Tarapur Station (2x210 MWe BWR) was built as a turnkey project which restricted participation of Indian engineers in design and construction considerably. The contrasting approach adopted for Rajasthan Station (2x220 MWe PHWR) involved Indian personnel and contractors fully in construction and commissioning, with Canadians providing supervisory assistance in Rajasthan I and essentially consultative help for Rajasthan II. Subsequent stations are wholly Indian efforts. Tarapur went into commercial operation in 1969, 60 months after breaking of ground. Construction was essentially uneventful, major problems faced being stress corrosion induced cracks in the reactor lining and complete change of steam generator tubes. In its seven years of operations, Tarapur has faced several problems mainly arising from rather early designs, indifferent fuel performance, constraints of twin-unit approach and operations in an inadequately developed grid system apart from those generally stemming from assimilation of an advanced technology in a developing country. The Station has undergone six refuellings during this period. Most of the problems have been overcome by design changes, system augmentations and experience and the Station operation since mid 1974 have generally been steady at around 90% of the rated capacity. Construction of Rajasthan I at a remote and isolated site proceeded relatively slowly. Local availability of skilled and semi-skilled manpower was poor, affecting construction. Inadequate roads impeded movements of overdimensioned components. Observing strict Quality Assurance standards required several major rectifications at site. Rajasthan I went on line in 1973 after overcoming major turbine bearing problems during commissioning. Since then, while

  19. TFTR neutral beam D-T gas injection system operational experiences of the first two years

    International Nuclear Information System (INIS)

    Oldaker, M.E.; Lawson, J.E.; Stevenson, T.N.; Kamperschroer, J.H.

    1995-01-01

    The TFTR Neutral Beam Tritium Gas Injection System (TGIS) has successfully performed tritium operations since December 1993. TGIS operation has been reliable, with no leaks to the secondary containment to date. Notable operational problems include throughput leaks on fill, exit and piezoelectric valves. Repair of a TGIS requires replacement of the assembly, involving TFTR downtime and extensive purging, since the TGIS assembly is highly contaminated with residual tritium, and is located within secondary containment. Modifications to improve reliability and operating range include adjustable reverse bias voltage to the piezoelectric valves, timing and error calculation changes to tune the PLC and hardwired timing control, and exercising piezoelectric valves without actually pulsing gas prior to use after extended inactivity. A pressure sensor failure required the development of an open loop piezoelectric valve drive control scheme, using a simple voltage ramp to partially compensate for declining plenum pressure. Replacement of TGIS's have been performed, maintaining twelve system tritium capability as part of scheduled project maintenance activity

  20. Mortality in perforated duodenal ulcer depends upon pre-operative risk: a retrospective 10-year study.

    LENUS (Irish Health Repository)

    Larkin, J O

    2012-01-31

    INTRODUCTION: Most patients presenting with acutely perforated duodenal ulcer undergo operation, but conservative treatment may be indicated when an ulcer has spontaneously sealed with minimal\\/localised peritoneal irritation or when the patient\\'s premorbid performance status is poor. We retrospectively reviewed our experience with operative and conservative management of perforated duodenal ulcers over a 10-year period and analysed outcome according to American Society of Anesthesiologists (ASA) score. METHODS: The records of all patients presenting with perforated duodenal ulcer to the Department of Surgery, Mayo General Hospital, between January 1998 and December 2007 were reviewed. Age, gender, co-morbidity, ASA-score, clinical presentation, mode of management, operative procedures, morbidity and mortality were considered. RESULTS: Of 76 patients included, 48 (44 operative, 4 conservative) were ASA I-III, with no mortality irrespective of treatment. Amongst 28 patients with ASA-score IV\\/V, mortality was 54.5% (6\\/11) following operative management and 52.9% (9\\/17) with conservative management. CONCLUSION: In patients with a perforated duodenal ulcer and ASA-score I-III, postoperative outcome is uniformly favourable. We recommend these patients have repair with peritoneal lavage performed, routinely followed postoperatively by empirical triple therapy. Given that mortality is equivalent between ASA IV\\/V patients whether managed operatively or conservatively, we suggest that both management options are equally justifiable.