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Sample records for periodic startup shutdown

  1. 40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

  2. 40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during CISWI unit startups, shutdowns, or malfunctions. (b) Each...

  3. 40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

  4. 40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

  5. 40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

  6. 40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Performance Testing ...

  7. 40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

  8. 40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

  9. 40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

  10. 40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

  11. 40 CFR 60.2120 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... 1, 2001 Emission Limitations and Operating Limits § 60.2120 What happens during periods of startup... during CISWI unit startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3...

  12. 40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Malfunction, startup, and shutdown..., startup, and shutdown regulations. (a) The following regulations are disapproved because they would permit... malfunctions and/or fail to sufficiently limit startup and shutdown exemptions to those periods where it is...

  13. 40 CFR 63.2852 - What is a startup, shutdown, and malfunction plan?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true What is a startup, shutdown, and... Production Compliance Requirements § 63.2852 What is a startup, shutdown, and malfunction plan? You must...)(2) malfunction period, or the § 63.2850(c)(2) or (d)(2) initial startup period. The SSM plan must...

  14. Startup and shutdown of the PULSAR Tokamak Reactor

    International Nuclear Information System (INIS)

    Werley, K.A.; Bathke, C.G.

    1994-01-01

    Start-up conditions are examined for a pulsed tokamak reactor that uses only inductive plasma current drive for startup, burn and shutdown. A zero-dimensional (profile-averaged) model that describes plasma power and particle balance equations is used to study several aspects of plasma startup and shutdown, including optimization of the startup pathway tradeoff of auxiliary startup heating power versus startup time, volt-second consumtion, thermal stability and partial-power operations

  15. BWR startup and shutdown activity transport control

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.E., E-mail: sgarcia@epri.com [Electric Power Research Inst. (EPRI), Palo Alto, California (United States); Giannelli, J.F.; Jarvis, A.J., E-mail: jgiannelli@finetech.com, E-mail: ajarvis@finetech.com [Finetech, Inc., Parsippany, New Jersey (United States)

    2010-07-01

    This paper summarizes BWR industry experience on good practices for controlling the transport of corrosion product activity during shutdowns, particularly refueling outages, and for startup chemistry control to minimize IGSCC (intergranular stress corrosion cracking). For shutdown, overall goals are to minimize adverse impacts of crud bursts and the time required to remove activated corrosion products from the reactor coolant during the shutdown process prior to refueling, and to assist plants in predicting and controlling radiation exposure during outages. For startup, the overall goals are to highlight conditions during early heatup and startup when sources of reactor coolant oxidants are high, when there is a greater likelihood for chemical excursions associated with refueling outage work activities, and when hydrogen injection is not available to mitigate IGSCC due to system design limitations. BWR water chemistry has changed significantly in recent years with the adoption of hydrogen water chemistry, zinc addition and noble metal chemical applications. These processes have, in some instances, resulted in significant activity increases during shutdown evolutions, which together with reduced time for cleanup because of shorter outages, has consequently increased outage radiation exposure. A review several recent outages shows that adverse effects from these conditions can be minimized, leading to the set of good practice recommendations for shutdown chemistry control. Most plants lose the majority of their hydrogen availability hours during early startup because feedwater hydrogen injection systems were not originally designed to inject hydrogen below 20% power. Hydrogen availability has improved through modifications to inject hydrogen at lower power levels, some near 5%. However, data indicate that IGSCC is accelerated during early startup, when dissolved oxygen and hydrogen peroxide levels are high and reactor coolant temperatures are in the 300 to 400 {sup o

  16. Startup, Shutdown, & Malfunction (SSM) Emissions

    Science.gov (United States)

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  17. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  18. 40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Requirements for startups, shutdowns, and malfunctions. 63.310 Section 63.310 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Coke Oven Batteries § 63.310 Requirements for startups, shutdowns...

  19. 77 FR 73968 - Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards...

    Science.gov (United States)

    2012-12-12

    ...; FRL-9762-1] RIN 2060-AR62 Reconsideration of Certain New Source and Startup/Shutdown Issues: National... Source and Startup/Shutdown Issues: National Emission Standards for Hazardous Air Pollutants from Coal... November 30, 2012, proposed ``Reconsideration of Certain New Source and Startup/Shutdown Issues: National...

  20. Standardization of the time for the execution of HANARO start-up and shutdown procedures

    International Nuclear Information System (INIS)

    Choi, H. Y.; Lim, I. C.; Hwang, S. R.; Kang, T. J.; Youn, D. B.

    2003-01-01

    For the standardization of the time to execute HANARO start-up and shutdown procedures, code names were assigned to the individual procedures and the work time were investigated. The data recorded by the operators during start-up and shutdown were statistically analyzed. The analysis results will be used for the standardization of start-up and shutdown procedures and it will be reflected in the procedure document

  1. Startup, Shutdown, & Malfunction (SSM) Emissions at Industrial Facilities

    Science.gov (United States)

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  2. Kinetic analyses on startup and shutdown chemistry of BWR plant

    International Nuclear Information System (INIS)

    Domae, Masafumi; Fujiwara, Kazutoshi; Inagaki, Hiromitsu

    2012-09-01

    During startup and shutdown of Boiling Water Reactor (BWR) plants, temperature and dissolved oxygen (DO) concentration of reactor water change in a wide range. The changes result in variation of conductivity and pH of the reactor water. It has been speculated that the water chemistry change is due to dissolution of the oxides on fuel claddings and structural materials. However, detailed mechanism is not known. In the present paper, trend of recent water chemistry in several BWR plants during startup and shutdown is presented. Conductivity and pH are convenient indication of coolant purity. We tried to clarify the mechanism of the change in the conductivity and the pH value during startup and shutdown, based on the water chemistry data measured. In the water chemistry data, change in chromate concentration and Ni 2+ concentration is rather large. It is assumed that change in the chromate concentration and the Ni 2+ concentration results in the time variation of the conductivity and the pH value. It is reasonable to consider that the increase in the chromate concentration and the Ni 2+ concentration is ascribed to dissolution of Cr oxides and Ni oxides, respectively. A model of dissolution of the Cr oxides and the Ni oxides is proposed. A concept of finite inventory of the Cr oxides and the Ni oxides in the coolant system is introduced. The model is as follows. Chromate is generated by oxidation of the Cr oxides and the Cr dissolution rate depends on the DO concentration. The dissolution rate of chromate is in proportion to DO concentration, the inventory of Cr and difference between solubility limit and the chromate concentration. On the other hand, Ni 2+ is formed by dissolution of the Ni oxides, and DO is not necessary in this process. The dissolution rate of Ni 2+ is in proportion to the inventory of Ni and difference between solubility limit and the Ni 2+ concentration. Coolant is continuously purified, and the chromate concentration and the Ni 2+ concentration

  3. Evaluation of power behavior during startup and shutdown procedures of the IPR-R1 Triga Reactor

    International Nuclear Information System (INIS)

    Zangirolami, Dante M.; Mesquita, Amir Z.; Ferreira, Andrea V.

    2009-01-01

    The IPR-R1 nuclear reactor of Centro de Desenvolvimento da Tecnologia Nuclear - CDTN/CNEN is a TRIGA Mark I pool type reactor cooled by natural circulation of light water. In the IPR-R1, the power is measured by four nuclear channels, neutron-sensitive chambers, which are mounted around the reactor core: the Startup Channel for power indication during reactor startup; the Logarithmic Wide Range Power Monitoring Channel; the Linear Multi-Range Power Monitoring Channel and the Percent Power Safety Channel. A data acquisition system automatically does the monitoring and storage of all the reactor operational parameters including the reactor power. The startup procedure is manual and the time to reach the desired reactor power level is different on each irradiation which may introduces differences in induced activity of samples irradiated in different irradiations. In this work, the power evolution during startup and shutdown periods of IPR-R1 operation was evaluated and the mean values of reactor energy production in these operational phases were obtained. The analyses were performed on basis of the Linear Multi-Range Channel data. The results show that the sum of startup and shutdown periods corresponds to 1% of released energy for irradiations during 1h at 100kW. This value may be useful to correct experimental data in neutron activation experiments. (author)

  4. Optimization of startup and shutdown operation of simulated moving bed chromatographic processes.

    Science.gov (United States)

    Li, Suzhou; Kawajiri, Yoshiaki; Raisch, Jörg; Seidel-Morgenstern, Andreas

    2011-06-24

    This paper presents new multistage optimal startup and shutdown strategies for simulated moving bed (SMB) chromatographic processes. The proposed concept allows to adjust transient operating conditions stage-wise, and provides capability to improve transient performance and to fulfill product quality specifications simultaneously. A specially tailored decomposition algorithm is developed to ensure computational tractability of the resulting dynamic optimization problems. By examining the transient operation of a literature separation example characterized by nonlinear competitive isotherm, the feasibility of the solution approach is demonstrated, and the performance of the conventional and multistage optimal transient regimes is evaluated systematically. The quantitative results clearly show that the optimal operating policies not only allow to significantly reduce both duration of the transient phase and desorbent consumption, but also enable on-spec production even during startup and shutdown periods. With the aid of the developed transient procedures, short-term separation campaigns with small batch sizes can be performed more flexibly and efficiently by SMB chromatography. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. On the startup and shutdown of a tandem mirror reactor

    International Nuclear Information System (INIS)

    Chang, F.R.; DeCanio, F.T.; Fisher, J.L.; Madden, P.A.

    1979-01-01

    The startup and shutdown of a fusion reactor must be performed in such a way that the plasma remains MHD stable. In a tandem mirror the stability depends on a sufficiently high pressure ratio between the plugs and the central cell, of the order of 100. Control of the neutral beam input to the plugs by means of active feedback has been investigated to achieve an acceptable pressure ratio throughout the entire startup/shutdown transient. An algorithm to control the beam input power has been developed. The control law was subsequently tested in a tandem mirror simulation code. This paper describes the basic models incorporated in the simulation, as well as the derivation of the control algorithm. The simulation results are presented and the practicality of implementing the algorithm is discussed. 4 refs

  6. 78 FR 38001 - Reconsideration of Certain Startup/Shutdown Issues: National Emission Standards for Hazardous Air...

    Science.gov (United States)

    2013-06-25

    ..., FRL-9827-1] RIN 2060-AR62 Reconsideration of Certain Startup/Shutdown Issues: National Emission... published in the Federal Register the proposed rule, ``Reconsideration of Certain New Source and Startup....'' That proposal opened for reconsideration certain issues, including those related to startup and...

  7. Changing nuclear plant operating limits during startup and shutdown

    International Nuclear Information System (INIS)

    Arnold, E.C.; Carlson, R.W.; Ray, N.K.; Roarty, D.H.

    1990-01-01

    During startup and shutdown operation of pressurized water reactor (PWR) nuclear power plants, a low pressure decay heat removal system is used to maintain core cooling. During these phases of operation, there are numerous operating practices and design limits to meet special and sometimes conflicting requirements unique to these operations. This paper evaluates the impact and interdependencies of recent issues on plant operation and design

  8. Transient fission-product release during reactor shutdown and startup

    International Nuclear Information System (INIS)

    Hunt, C.E.L.; Lewis, B.J.; Dickson, L.W.

    1997-12-01

    Sweep-gas experiments performed at AECL's Chalk River Laboratories from 1979 to 1985 have been further analysed to determine the fraction of the gaseous fission-product inventory that is released on reactor shutdown and startup. Empirical equations were derived and applied to calculate the stable xenon release from companion fuel elements and from a well-documented experimental fuel bundle irradiated in the NRU reactor. The calculated gas release could be matched to the measured values within about a factor of two for an experimental irradiation with a burnup of 217 MWh/kgU. There was also limited information on the fraction of the radioactive iodine that was exposed, but not released, on reactor shutdown. An empirical equation is proposed for calculating this fraction. (author)

  9. Transient fission product release during reactor shutdown and startup

    International Nuclear Information System (INIS)

    Hunt, C.E.L.; Lewis, B.J.

    1995-01-01

    Sweep gas experiments performed at CRL from 1979 to 1985 have been analysed to determine the fraction of the fission product gas inventory that is released on reactor shutdown and startup. Empirical equations were derived and applied to calculate the xenon release from companion fuel elements and from a well documented experimental fuel bundle irradiated in the NRU reactor. The measured gas release could be matched to within about a factor of two for an experimental irradiation with a burnup of 217 MWh/kgU. (author)

  10. Development of Start-up and Shutdown Procedure for the HANARO Fuel Test Loop

    International Nuclear Information System (INIS)

    Park, S. K.; Sim, B. S.; Chi, D. Y.; Lee, J. M.; Lee, C. Y.; Ahn, S. H.

    2009-06-01

    A start-up and shutdown procedure for the HANARO fuel test loop has been developed. This is a facility for fuel and material irradiation tests. The facility provides experimental conditions similar to the normal operational pressures and temperatures of commercial PWR and CANDU plants. The normal operation modes of the HANARO fuel test loop are classified into loop shutdown, cold stand-by 1, cold stand-by 2, hot stand-by, and hot operation. The operation modes depend on the fission power of test fuels and the coolant temperature at the inlet of the in-pile test section. The HANARO must maintain a shutdown mode if the HANARO fuel test loop is loop shutdown, cold stand-by 1, cold stand-by 2, or hot stand-by. As the HANARO becomes power operation mode, the operation mode of the HANARO fuel test loop comes to hot operation from hot stand-by. The procedure for the HANARO fuel test loop consists of four main parts such as check of initial conditions, stat-up operation procedure, shutdown operation procedure, and check lists for operations. Several hot test operations ensure that the procedure is appropriate

  11. 77 FR 72294 - Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards...

    Science.gov (United States)

    2012-12-05

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 60 and 63 [EPA-HQ-OAR-2009-0234; EPA-HQ-OAR-2011-0044; FRL-9733-2] RIN 2060-AR62 Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric Utility Steam Generating...

  12. Lithium Hideout and Return in the CANDU Heat Transport System during Shutdown and Start-up

    International Nuclear Information System (INIS)

    Qiu, L.; Snaglewski, A.P.

    2012-09-01

    Lithium hydroxide is used to control the pH a (pH apparent) of the Heat Transport System (HTS) coolant in CANDU R reactors. The recommended range of the lithium concentration in the coolant is between 0.38 ppm (5.5x10 -5 m) and 0.60 ppm (8.7x10 -5 m) to minimize carbon steel corrosion in the HTS and magnetite deposition in the core during normal operation; this corresponds to pH a values between 10.2 and 10.4. Similar pH a and lithium concentrations should be maintained during shutdown and start-up. However, maintaining the pH a of the HTS coolant within specification during shutdown and start-up has been difficult for some CANDU stations, especially when the HTS is taken to a Low Level Drain State (LLDS), because of lithium hideout and return. This paper presents the results from lithium adsorption and desorption studies on iron oxides under relevant shutdown and start-up chemistry conditions performed to elucidate the mechanisms of the observed lithium hideout and return. The results show that lithium hideout and return are driven largely by changes in the solubility of magnetite as the HTS coolant chemistry changes during shutdown; changes in lithium concentration were inversely correlated with the solubility of magnetite. When the HTS system is de-pressurized and drained to a low coolant level, the ingress of air rapidly oxidizes the dissolved Fe (II) in the coolant, 2Fe +2 + 1 / 2 O 2 + 3 H 2 = 2FEOOH + 4 H + , resulting in the formation of lepidocrocite or maghemite, which have much lower solubilities but larger surface areas than does magnetite. The large surface area of the Fe (III) oxides can adsorb significant quantities of lithium from the coolant, leading to lithium hideout and a pH a decrease. During start-up, the chemistry of the coolant changes from oxidizing to reducing, and lepidocrocite and other Fe (III) oxides are reduced to Fe (II), gradually dissolving as their solubility increases with increasing temperature. The adsorbed lithium is released

  13. Modeling startup and shutdown transient of the microlinear piezo drive via ANSYS

    Science.gov (United States)

    Azin, A. V.; Bogdanov, E. P.; Rikkonen, S. V.; Ponomarev, S. V.; Khramtsov, A. M.

    2017-02-01

    The article describes the construction-design of the micro linear piezo drive intended for a peripheral cord tensioner in the reflecting surface shape regulator system for large-sized transformable spacecraft antenna reflectors. The research target -the development method of modeling startup and shutdown transient of the micro linear piezo drive. This method is based on application software package ANSYS. The method embraces a detailed description of the calculation stages to determine the operating characteristics of the designed piezo drive. Based on the numerical solutions, the time characteristics of the designed piezo drive are determined.

  14. Shutdown problems in large tokamaks

    International Nuclear Information System (INIS)

    Weldon, D.M.

    1978-01-01

    Some of the problems connected with a normal shutdown at the end of the burn phase (soft shutdown) and with a shutdown caused by disruptive instability (hard shutdown) have been considered. For a soft shutdown a cursory literature search was undertaken and methods for controlling the thermal wall loading were listed. Because shutdown computer codes are not widespread, some of the differences between start-up codes and shutdown codes were discussed along with program changes needed to change a start-up code to a shutdown code. For a hard shutdown, the major problems are large induced voltages in the ohmic-heating and equilibrium-field coils and high first wall erosion. A literature search of plasma-wall interactions was carried out. Phenomena that occur at the plasma-wall interface can be quite complicated. For example, material evaporated from the wall can form a virtual limiter or shield protecting the wall from major damage. Thermal gradients that occur during the interaction can produce currents whose associated magnetic field also helps shield the wall

  15. Comparing Non-Steady State Emissions under Start-Up and Shut-Down Operating Conditions with Steady State Emissions for Several Industrial Sectors: A Literature Review

    Directory of Open Access Journals (Sweden)

    Juwairia Obaid

    2017-02-01

    Full Text Available This study investigates the emissions of various industrial facilities under start-up, shut-down, and normal operations. The industries that have been investigated include power and/or heat generation, energy-from-waste generation, nuclear power generation, sulphuric acid production, ethylene production, petrochemical production, and waste incineration. The study investigated multiple facilities worldwide for each of these industrial categories. The different potential contaminants characteristic of each industry type have been investigated and the emissions of these contaminants under non-steady state have been compared to the steady state emissions. Where available, trends have been developed to identify the circumstances, i.e., the industrial sector and contaminant, under which the assessment and consideration of emissions from start-up and shut-down events is necessary for each industry. These trends differ by industrial sector and contaminant. For example, the study shows that sulphur dioxide (SO2 emissions should be assessed for the start-up operations of sulphuric acid production plants, but may not need to be assessed for the start-up operations of a conventional power generation facility. The trends developed as part of this research paper will help air permit applicants to effectively allocate their resources when assessing emissions related to non-steady state operations. Additionally, it will ensure that emissions are assessed for the worst-case scenario. This is especially important when emissions under start-up and shut-down operations have the potential to exceed enforceable emission limits. Thus, assessing emissions for the worst-case scenario can help in preventing the emissions from adversely impacting public health and the environment.

  16. WIMS-AECL/RFSP code validation of reactivity calculations following a long shutdown using the simple-cell history-based method

    International Nuclear Information System (INIS)

    Ardeshiri, F.; Donnelly, J.V.; Arsenault, B.

    1998-01-01

    The purpose of this analysis is to validate the Reactor Fuelling Simulation Program (RFSP) using the simple-cell model (SCM) history-based method in a startup simulation following a reactor shutdown period. This study is part of the validation work for history-based calculations, using the WIMS-AECL code with the ENDF/B-V library, and the SCM linked to the RFSP code. In this work, the RFSP code with the SCM history-based method was used to track a 1-year period of the Point Lepreau reactor operating history, that included a 12-day reactor shutdown and subsequent startup. Measured boron and gadolinium concentrations were used in the RFSP simulations, and the predicted values of core reactivity were compared to the reference (pre-shutdown) value. The discrepancies in core reactivity are shown to be better than ±2 milli-k at any time, and better than about ±0.5 milli-k towards the end of the startup transient. The results of this analysis also show that the calculated maximum channel and bundle powers are within an acceptable range during both the core-follow and the reactor startup simulations. (author)

  17. Loop Heat Pipe Startup Behaviors

    Science.gov (United States)

    Ku, Jentung

    2016-01-01

    A loop heat pipe must start successfully before it can commence its service. The startup transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe startup behaviors. Topics include the four startup scenarios, the initial fluid distribution between the evaporator and reservoir that determines the startup scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power startup, and methods to enhance the startup success. Also addressed are the pressure spike and pressure surge during the startup transient, and repeated cycles of loop startup and shutdown under certain conditions.

  18. 75 FR 26892 - Approval and Promulgation of Implementation Plans; Texas; Excess Emissions During Startup...

    Science.gov (United States)

    2010-05-13

    ... corrective action to avoid a malfunction, then the event is considered an unplanned maintenance activity or... Promulgation of Implementation Plans; Texas; Excess Emissions During Startup, Shutdown, Maintenance, and... Emissions Events and Scheduled Maintenance, Startup, and Shutdown Activities. This action proposes approval...

  19. Improvement of operational efficiency based on fast startup plant concepts

    Energy Technology Data Exchange (ETDEWEB)

    Grumann, Ulrich; Kurz, Harald; Meinecke, Gero; Pickard, Andreas

    2010-09-15

    The power generation sector is currently confronted with new challenges relating to the conservation of dwindling fuel reserves. At the same time we must reduce CO2 emissions in order to counteract global warming. This paper shows that power plant operation, which employs shutdowns during periods of low load demand coupled with the optimization of startup procedures are a key to reducing CO2 emissions and to conserving resources. The startup technology developed by Siemens also offers grid support in the event of naturally occurring failures of renewable energy sources. Additionally, plant profitability is improved due to the resulting savings in fuel.

  20. Impact of start-up and shut-down losses on the economic benefit of an integrated hybrid solar cavity receiver and combustor

    International Nuclear Information System (INIS)

    Lim, Jin Han; Hu, Eric; Nathan, Graham J.

    2016-01-01

    Highlights: • We present the benefits of integrating a solar cavity receiver and a combustor. • The hybrid solar receiver combustor is compared with its equivalent hybrid. • The start-up losses of the back-up boiler are calculated for a variable resource. • Levelized cost of electricity is reduced by up to 17%. • Fuel consumption is reduced by up to 31%. - Abstract: The impact of avoiding the start-up and shut-down losses of a solar thermal power plant by directly integrating the back-up boiler into a tubular solar-only cavity receiver is studied using a multiple time-step, piecewise-continuous model. A steady-state analytical model of the mass and energy flows through both this device and a solar-only cavity receiver reported previously are incorporated within a model of the solar power generating plant with storage. The performance of the Hybrid Solar Receiver Combustor (HSRC) is compared with an equivalent reference conventional hybrid solar thermal system employing a solar-only cavity receiver and a back-up boiler. The model accounts for start-up and shut-down losses of the boiler, threshold losses of the solar-only cavity receiver and the amount of trace heating required to avoid cooling of the heat transfer fluid. The model is implemented for a 12 month/five year time-series of historical Direct Normal Irradiation (DNI) at 1 h time-steps to account for the variability in the solar resource at four sites spanning Australia and the USA. A method to optimize the size of the heliostat field is also reported, based on the dumped fraction of solar power from the heliostat field. The Levelized Cost of Electricity (LCOE) for the HSRC configuration was estimated to be reduced by up to 17% relative to the equivalent conventional hybrid solar thermal system depending on the cost of the fuel, the storage capacity and the solar resource, while the fuel consumption was estimated to be reduced by some 12–31%.

  1. Deaerating operation during startup periods in Japanese BWRs

    International Nuclear Information System (INIS)

    Maeda, K.

    2002-01-01

    The IGSCC has been mitigated by application of effective countermeasures on water chemistry environment. Hydrogen water chemistry (HWC) has been implemented to reduce the reactor water dissolved oxygen concentration and electrochemical corrosion potential (ECP) during plant operation to reduced crack growth rate of in sensitized stainless steel. But the HWC has not been implemented during startup periods. The crack growth rate of sensitized stainless steel will increase obviously during startup period by increasing in temperature under high dissolved oxygen conditions [1]. The deaerating operation has been applied routinely in Japanese BWRs to reduce reactor water dissolved oxygen quickly and easily before plant startup [2,3]. The main condenser is vacuumed up before start in the deaerating operation. The reactor is connected with the main condenser by opening the main steam bypass valves or the main steam drain valves. The deaerating operation is started with keeping the reactor water temperature about 70 to 90 degrees centigrade. The deaerating operation will come to an end when the reactor water dissolved concentration will decrease below 200 ppb. This paper shows the procedure and actual results of deaerating operation. (authors)

  2. Numerical Investigation of Transient Flow in a Prototype Centrifugal Pump during Startup Period

    Science.gov (United States)

    Zhang, Yu-Liang; Zhu, Zu-Chao; Dou, Hua-Shu; Cui, Bao-Ling; Li, Yi; Zhou, Zhao-Zhong

    2017-05-01

    Transient performance of pumps during transient operating periods, such as startup and stopping, has drawn more and more attentions recently due to the growing engineering needs. During the startup period of a pump, the performance parameters such as the flow rate and head would vary significantly in a broad range. Therefore, it is very difficult to accurately specify the unsteady boundary conditions for a pump alone to solve the transient flow in the absence of experimental results. The closed-loop pipe system including a centrifugal pump is built to accomplish the self-coupling calculation. The three-dimensional unsteady incompressible viscous flow inside the passage of the pump during startup period is numerically simulated using the dynamic mesh method. Simulation results show that there are tiny fluctuations in the flow rate even under stable operating conditions and this can be attributed to influence of the rotor-stator interaction. At the very beginning of the startup, the rising speed of the flow rate is lower than that of the rotational speed. It is also found that it is not suitable to predict the transient performance of pumps using the calculation method of quasi-steady flow, especially at the earlier period of the startup.

  3. Characteristics of HTTR's startup physics tests

    International Nuclear Information System (INIS)

    Nojiri, N.; Nakano, M.; Takeuchi, M.; Pohl, P.; Yamashita, K.

    1997-01-01

    The High Temperature Engineering Test Reactor (HTTR) which is under construction by Japan Atomic Energy Research Institute (JAERI) is a graphite-moderated and helium gas-cooled reactor with an outlet temperature of 950 deg. C and a thermal output of 30MW. The first criticality is expected at the end of October 1997. The start-up physics tests (SPTs) are planned in the period from mid 1997 to the end of 1998. Characteristic items of the SPTs are: 1) Criticality approach; 2) Tests on a preliminary annual core; 3) Measurement of scram reactivity; 4) Excess reactivity test; 5) Measurements along with a 2-step-scram reactor shutdown procedure. (author)

  4. Safety analysis of Ignalina NPP during shutdown conditions

    International Nuclear Information System (INIS)

    Kaliatka, A.; Uspuras, E.

    2000-01-01

    The accident analysis for the Ignalina NPP with RBMK-1500 reactors at normal operating conditions and at minimum controlled power level (during startup of the reactor) has been performed in the frame of the project I n-Depth Safety Assessment of the Ignalina NPP , which was completed in 1996. However, the plant conditions during the reactor shutdown differ from conditions during reactor operation at full power (equipment status in protection systems, set points for actuation of safety and protection systems, etc.). Results of RELAP5 simulation of two worst initiating events during reactor shutdown - Pressure Header rupture in case of steam reactor cooldown as well as Pressure Header rupture in case of water reactor cooldown are discussed in the paper. Results of analysis shown that reactor are reliably cooled in both cases. Further analysis for all range of initial events during reactor shutdown and at shutdown conditions is recommended. (author)

  5. Influence of start-ups with fuel-oil on the operation of electrostatic precipitators in pulverised coal boilers

    Energy Technology Data Exchange (ETDEWEB)

    Navarrete, B.; Vilches, L.F.; Canadas, L.; Salvador, L. [University of Seville, Seville (Spain)

    2004-04-01

    This article describes the results of a series of tests carried out in a pilot fly ash electrostatic precipitation facility operating with real gases from a 550 MWe pulverized coal-fired power station. The main goal of these tests was to determine the effects of boiler start-ups on the performance of the electrostatic preciptator. The tests were carried out during start-ups of the power station boiler. All tests were carried out with the same fuel. An evaluation was made of the effects of the use of fuel-oil as auxillary fuel in start-ups and shut-downs of the boiler, and different electrostatic precipitators operation procedures were tested during start-ups and shut-downs. The results of the experiments made it possible to assess the relative importance of different variables on the possible deterioration of the efficiency of the precipitators. Also evaluated were operational modes that have demonstrated an improvement in the performance of the precipitators after the transient stage of these operations. As a result of this study, a number of important operational recommendations are made on boiler start-up and shut-down procedures.

  6. SEPRA - shutdown PSA for the OLKILUOTO nuclear power plant

    International Nuclear Information System (INIS)

    Himanen, R.

    1995-01-01

    The utility TVO has extended the PSA study to the analysis of refueling, shutdown and startup. The Shutdown Event PRA (SEPRA) was reported to the authority in September 1992. The study consists of the analysis of leaks and loss of decay heat removal in the planned shutdown conditions. Special studies were performed for the cold pressurization, for local criticality events, for heavy load transport and for the transients during startup and shutdown. A remarkable effort was put to identify risks, i.e. to the qualitative analysis. The regular preventive maintenance tasks in the refueling outages were analyzed and the important tasks were selected for further studies. Besides the severe core damage risk the utility was interested in less grave consequences, e.g. the economic risks, causing significant extension of outages. The plant specific screening of initiators consisted of a study on the incident history and of interviewing the plant personnel on selected tasks. A number of thermohydraulic calculations were carried out to support the analysis of accident sequences. The operator actions after an initiating event were verified with the operating staff. The annual core damage risk from the refueling outage is about one forth of the total annual risk. The modifications decreased significantly the core damage frequency. It is foreseen that the SEPRA will form a basis of the procedure enhancement for the low power states. (author) 5 figs., 1 tab., 10 refs

  7. Simulation of startup period of hydrogen isotope separation distillation column

    International Nuclear Information System (INIS)

    Sazonov, A.B.; Kagramanov, Z.G.; Magomedbekov, Eh.P.

    2003-01-01

    Kinetic procedure for the mathematical simulation of start-up regime of rectification columns for molecular hydrogen isotope separation was developed. Nonstationary state (start-up period) of separating column for rectification of multi-component mixture was calculated. Full information on equilibrium and kinetic physicochemical properties of components in separating mixtures was used for the calculations. Profile of concentration of components by height of column in task moment of time was calculated by means of differential equilibriums of nonstationary mass transfer. Calculated results of nonstationary state of column by the 2 m height, 30 mm diameter during separation of the mixture: 5 % protium, 70 % deuterium, 25 % tritium were illustrated [ru

  8. Primary circuit water chemistry during shutdown period at Kalinin NPP

    International Nuclear Information System (INIS)

    Gorbatenko, S.; Otchenashev, G.; Yurmanov, V.

    2005-01-01

    The primary circuit water chemistry feature at Kalinin NPP is using of special up-dated regime during the period of unit shutdown for refueling. The main objective of up-dated regime is removing from the circuit long time living corrosion products on SVO-2 ion exchange filters with the purpose of dose rates reduction from the equipment and in such a way reduction of maintenance personnel overexposure. (N.T.)

  9. Microbiology and performance of a methanogenic biofilm reactor during the start-up period.

    Science.gov (United States)

    Cresson, R; Dabert, P; Bernet, N

    2009-03-01

    To understand the interactions between anaerobic biofilm development and process performances during the start-up period of methanogenic biofilm reactor. Two methanogenic inverse turbulent bed reactors have been started and monitored for 81 days. Biofilm development (adhesion, growth, population dynamic) and characteristics (biodiversity, structure) were investigated using molecular tools (PCR-SSCP, FISH-CSLM). Identification of the dominant populations, in relation to process performances and to the present knowledge of their metabolic activities, was used to propose a global scheme of the degradation routes involved. The inoculum, which determines the microbial species present in the biofilm influences bioreactor performances during the start-up period. FISH observations revealed a homogeneous distribution of the Archaea and bacterial populations inside the biofilm. This study points out the link between biodiversity, functional stability and methanogenic process performances during start-up of anaerobic biofilm reactor. It shows that inoculum and substrate composition greatly influence biodiversity, physiology and structure of the biofilm. The combination of molecular techniques associated to a biochemical engineering approach is useful to get relevant information on the microbiology of a methanogenic growing biofilm, in relation with the start-up of the process.

  10. RECAP, Replacement Energy Cost for Short-Term Reactor Plant Shut-Down

    International Nuclear Information System (INIS)

    VanKuiken, J.C.; Daun, C.J.; Jusko, M.J.

    1995-01-01

    1 - Description of program or function: RECAP (Replacement Energy Cost Analysis Package) determines the replacement energy costs associated with short-term shutdowns or de-ratings of one or more nuclear reactors. Replacement energy cost refers to the change in generating-system production cost that results from shutting down a reactor. The cost calculations are based on the seasonal, unit-specific cost estimates for 1988-1991 for all 117 nuclear electricity-generating units in the U.S. RECAP is menu-driven, allowing the user to define specific case studies in terms of parameters such as the units to be included, the length and timing of the shutdown or de-rating period, the unit capacity factors, and the reference year for reporting cost results. In addition to simultaneous shutdown cases, more complicated situations, such as overlapping shutdown periods or shutdowns that occur in different years, can be examined through use of a present-worth calculation option. 2 - Method of solution: The user selects a set of units for analysis, defines a shutdown (or de-rating) period, and specifies any planned maintenance outages, delays in unit start-ups, or changes in default capacity factors. The program then determines which seasonal cost numbers to apply, estimates total and daily costs, and makes the appropriate adjustments for multiple outages if they are encountered. The change in production cost is determined from the difference between the total variable costs (variable fuel cost, variable operation and maintenance cost, and purchased energy cost) when the reactor is available for generation and when it is not. Changes in reference-year dollars are based on gross national product (GNP) price deflators or on optional use inputs. Once RECAP has completed the initial cost estimates for a case study (or series of case studies), present-worth analysis can be conducted using different reference-year dollars and discount rates, as specified by the user. The program uses

  11. Optimization of reactor coolant shutdown chemistry practices for crud inventory management

    International Nuclear Information System (INIS)

    Fellers, B.; Barnette, J.; Stevens, J.; Perkins, D.

    2002-01-01

    This report describes reactor coolant shutdown chemistry control practices at Comanche Peak Steam Electric Station (CPSES, TXU-Generation, USA). The shutdown evolution is managed from a process control perspective to achieve conditions most favorable to crud decomposition and to avoiding re-precipitation of metals. The report discusses the evolution of current industry practices and the necessity for greater emphasis on shutdown chemistry control in response to Axial Offset Anomaly and growth of ex-core radiation fields during outage conditions. Nuclear Industry experience with axial offset anomaly (AOA), radiation field growth and unexpected behavior of crud during reactor shutdowns has encouraged the refinement of chemistry control practices during plant shutdown and startup. The strong implication of nickel rich crud as a cause of AOA and unexpected crud behavior has resulted in a focus on nickel inventory management. The goals for Comanche Peak Steam Electric Station (CPSES) include maintaining solubility of metals and radioisotopes, maximizing nickel removal and effective cleanup with demineralizers. This paper provides results and lessons learned from long term efforts to optimize the shutdown process. (authors)

  12. Preliminary analyses for HTTR's start-up physics tests by Monte Carlo code MVP

    International Nuclear Information System (INIS)

    Nojiri, Naoki; Nakano, Masaaki; Ando, Hiroei; Fujimoto, Nozomu; Takeuchi, Mitsuo; Fujisaki, Shingo; Yamashita, Kiyonobu

    1998-08-01

    Analyses of start-up physics tests for High Temperature Engineering Test Reactor (HTTR) have been carried out by Monte Carlo code MVP based on continuous energy method. Heterogeneous core structures were modified precisely, such as the fuel compacts, fuel rods, coolant channels, burnable poisons, control rods, control rod insertion holes, reserved shutdown pellet insertion holes, gaps between graphite blocks, etc. Such precise modification of the core structures was difficult with diffusion calculation. From the analytical results, the followings were confirmed; The first criticality will be achieved around 16 fuel columns loaded. The reactivity at the first criticality can be controlled by only one control rod located at the center of the core with other fifteen control rods fully withdrawn. The excess reactivity, reactor shutdown margin and control rod criticality positions have been evaluated. These results were used for planning of the start-up physics tests. This report presents analyses of start-up physics tests for HTTR by MVP code. (author)

  13. Preliminary analyses for HTTR`s start-up physics tests by Monte Carlo code MVP

    Energy Technology Data Exchange (ETDEWEB)

    Nojiri, Naoki [Science and Technology Agency, Tokyo (Japan); Nakano, Masaaki; Ando, Hiroei; Fujimoto, Nozomu; Takeuchi, Mitsuo; Fujisaki, Shingo; Yamashita, Kiyonobu

    1998-08-01

    Analyses of start-up physics tests for High Temperature Engineering Test Reactor (HTTR) have been carried out by Monte Carlo code MVP based on continuous energy method. Heterogeneous core structures were modified precisely, such as the fuel compacts, fuel rods, coolant channels, burnable poisons, control rods, control rod insertion holes, reserved shutdown pellet insertion holes, gaps between graphite blocks, etc. Such precise modification of the core structures was difficult with diffusion calculation. From the analytical results, the followings were confirmed; The first criticality will be achieved around 16 fuel columns loaded. The reactivity at the first criticality can be controlled by only one control rod located at the center of the core with other fifteen control rods fully withdrawn. The excess reactivity, reactor shutdown margin and control rod criticality positions have been evaluated. These results were used for planning of the start-up physics tests. This report presents analyses of start-up physics tests for HTTR by MVP code. (author)

  14. Start-up performance of parabolic trough concentrating solar power plants

    DEFF Research Database (Denmark)

    Ferruzza, Davide; Topel, Monika; Basaran, Ibrahim

    2017-01-01

    Concentrating solar power plants, even though they can be integrated with thermal energy storage, are still subjected to cyclic start-up and shut-downs. As a consequence, in order to maximize their profitability and performance, the flexibility with respect to transient operations is essential...

  15. Reactor shutdown device

    International Nuclear Information System (INIS)

    Matsumiya, Hirohito; Endo, Hiroshi; Tsuboi, Yasushi.

    1993-01-01

    The present invention concerns a reactor shutdown device capable of suppressing change of a core insertion amount relative to temperature change during normal operation and having a great extension amount due to thermal expansion and high mechanical strength. A control rod main body is contained vertically movably in a guide tube disposed in a reactor core. An extension member extends upward from the upper end of a control rod main body and suspends the control rod main body. A shrinkable member intervenes at a midway of the extension member and is made shrinkable. A temperature sensitive member contains coolants at the inside and surrounds the shrinkable member. Thus, if the temperature of external coolants rises abruptly, the shrinkable member is extended by thermal expansion of the coolants in the temperature sensitive member. Upon usual reactor startup, the coolants in the temperature sensitive member cause no substantial thermal expansion by temperature elevation from a cold shutdown temperature to a rated power operation temperature, and the shrinkable member maintains its original state, so that the control rod main body is not inserted into the reactor core. However, upon abrupt temperature elevation, the control rod main body is inserted into the reactor core. (I.S.)

  16. Program of RA reactor start-up to nominal power

    International Nuclear Information System (INIS)

    1959-01-01

    The zero start-up program is followed by the program of RA reactor start-up to nominal power. This program is described in detail and includes the following measurements: radiation characteristics at the exit of the channels; gamma and fast neutron dose distribution in the reactor; influence of absorbers on the reactivity; temperature effect; absolute flux and calibration of ionization chambers; xenon effect; thermal and hydraulics; dosimetry around the reactor; neutron flux in the reactor core and in the reactor hall; heavy water level; thermal characteristics after shutdown. A list of measuring devices and instrumentation is included with the detailed action plan and list of responsible staff members

  17. Neutron flux monitoring with pre-startup channels in FBTR [Paper No.:E6

    International Nuclear Information System (INIS)

    Nagaraj, C.P.; Ramakrishnan, R.; Subha Rao, R.; Pillai, C.P.; Muralikrishan, G.; Raghavan, K.

    1993-01-01

    The pre-start up instrumentation system using boron lined proportional counters has been well designed and the counters have been rigorously tested. This system in conjunction with the regular start-up channels (with more than 3 decades overlap) covers the start up measurement range adequately and provides necessary indications, interlocks and trips on low count rate, high count rate and doubling time to ensure safety. The pre-startup channels have been operational. The reactor trip on LOG NO due to count rate on start-up channels less than 3 cps is automatically inhibited with the higher count rate obtained on the pre-startup channels. With this and log CRM readings from PSU well on scale has facilitated smooth and safe reactor start ups even with low shutdown count rates. (author). 5 figs

  18. Output of the type 4051 and 4061 period meters during startup transients

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1963-05-01

    The report describes a digital computer programme for the Ferranti Mercury computer. With this programme startup transients for the recently developed period meters Types 4051 and 4061 may be computed. The reactivity disturbances considered are steps and terminated ramps of reactivity. Due allowance is taken of the variable time constant which is a feature of these period meters. The reactor may be critical or subcritical initially as desired and the initial input time constant of the period meter may be zero or finite. Some representative transients obtained with the programme are presented and discussed. (author)

  19. User's guide of DETRAS system-2. Setup of DETRAS system and its startup

    International Nuclear Information System (INIS)

    Yamaguchi, Yukichi

    2007-01-01

    DETRAS system is a PWR reactor simulator system for operation training whose distinguished feature is that it can be operated from the remote place of the simulator site. The document which is the second one of a series of three volumes of the user's guide of DETRAS describes a startup procedure of the DETRAS system over the simulator area, the local network involving the simulator and then gives explanation about the procedure of remote access for startup and shutdown of the simulator outside of the simulator area. (author)

  20. 40 CFR 63.152 - General reporting and continuous records.

    Science.gov (United States)

    2010-07-01

    ... the compliance dates specified in § 63.100 of subpart F of this part. (1) The notification shall... quarter of the year. The first quarter begins on the compliance date specified in § 63.100 of subpart F... determining compliance. (1) Periods of startup, shutdown, or malfunction. During periods of startup, shutdown...

  1. Internal currents in PEMFC during start-up or shut-down

    Energy Technology Data Exchange (ETDEWEB)

    Maranzana, G.; Lottin, O.; Moyne, C.; Dillet, J.; Lamibrac, A.; Mainka, J.; Didierjean, S. [Nancy Univ. - CNRS (France). LEMTA

    2010-07-01

    Experiments show that the internal currents that occur during PEMFC start-up can reach up to 1 Acm{sup -2}. This is far more important than the expected order of magnitude of the current densities associated with carbon oxidation, which is only of a few mAcm{sup -2}. The predominant phenomenon that explains the internal currents is the charge and discharge of the double layer capacitances. A simple model with constant values of the electric parameters yields numerical results close to the experimental ones. It also explains the transient voltage rise (over the steady state open circuit voltage) that is sometimes observed experimentally shortly after the fuel cell start up. (orig.)

  2. Application of startup/core management code system to YGN 3 startup testing

    International Nuclear Information System (INIS)

    Chi, Sung Goo; Hah, Yung Joon; Doo, Jin Yong; Kim, Dae Kyum

    1995-01-01

    YGN 3 is the first nuclear power plant in Korea to use the fixed incore detector system for startup testing and core management. The startup/core management code system was developed from existing ABB-C-E codes and applied for YGN 3 startup testing, especially for physics and CPC(Core Protection Calculator)/COLSS (Core Operating Limit Supervisory System) related testing. The startup/core management code system consists of startup codes which include the CEBASE, CECOR, CEFAST and CEDOPS, and startup data reduction codes which include FLOWRATE, COREPERF, CALMET, and VARTAV. These codes were implemented on an HP/Apollo model 9000 series 400 workstation at the YGN 3 site and successfully applied to startup testing and core management. The startup codes made a great contribution in upgrading the reliability of test results and reducing the test period by taking and analyzing core data automatically. The data reduction code saved the manpower and time for test data reduction and decreased the chance for error in the analysis. It is expected that this code system will make similar contributions for reducing the startup testing duration of YGN 4 and UCN3,4

  3. Emissions Characterisation of residential pellet boilers during start-up and stop periods

    OpenAIRE

    Win, Kaung Myat; Paavilainen, Janne; Persson, Tomas

    2010-01-01

    In this study, gaseous emissions and particles are measured during start-up and stop periods for an over-fed boiler and an under-fed boiler. Both gaseous and particulate matter emissions are continuously measured in the laboratory. The measurement of gaseous emissions includes oxygen (O2), carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxide and (NO). The emissions rates are calculated from measured emissions concentrations and flue gas flow. The behaviours of the boilers during start-u...

  4. Quality assurance during preoperational testing and during startup operation

    International Nuclear Information System (INIS)

    Eisele, H.; Meyer, F.A.

    1980-01-01

    Rules and guidelines for the quality assurance. Quality assurance in the course of preoperational testing and the startup period: preoperational testing; hot functional test I; hot functional test II; initial making critical and zero power physics testing; power range testing. Startup documents: startup program; startup instructions; startup data sheet; startup sequence outlines; final startup reports. Advisory safety committee for nuclear startup. (orig./RW)

  5. 40 CFR 63.4312 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... occurred during a period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records required to show continuous... capture efficiency of 100 percent, as specified in § 63.4361(a). (5) For each capture system that is not a...

  6. 40 CFR 63.102 - General standards.

    Science.gov (United States)

    2010-07-01

    ... extent practical. The general duty to minimize emissions during a period of startup, shutdown, or... procedures (including the startup, shutdown, and malfunction plan required in § 63.6(e)(3)), review of... § 63.100(k) of this subpart. [59 FR 19454, Apr. 22, 1994, as amended at 60 FR 63626, Dec. 12, 1995; 61...

  7. 40 CFR 63.4530 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... occurred during a period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records required to show continuous... capture efficiency of 100 percent, as specified in § 63.4565(a). (5) For each capture system that is not a...

  8. 40 CFR 63.3512 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... occurred during a period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records required to show continuous... capture efficiency of 100 percent, as specified in § 63.3544(a). (5) For each capture system that is not a...

  9. Analysis of Gamma Dose Rate Caused by Corrosion Products inside the Containment Building of Yonngwang Nuclear Power Plant Unit 3 During Shutdown Period

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Wi Ho; Kim, Jae Cheon; Kim, Soon Young; Kim, Jong Kyung [Hanyang Univ., Seoul (Korea, Republic of)

    2005-07-01

    Occupational radiation exposure(ORE) of nuclear power plant(NPP) workers mainly occurs during the shutdown period. Major radioactive sources are the corrosion products released from the reactor coolant system(RCS). The corrosion products consist of circulating crud and deposited crud. Major radioactive corrosion products, {sup 58}Co and {sup 60}Co, are known to contribute approximately more than 70% of the total ORE. In this study, the corrosion products regarding cobalt were evaluated during the shutdown period, and gamma dose rates caused by them were calculated at the main working area inside the containment building of the Yonggwang NPP Unit 3.

  10. 40 CFR 63.4130 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records required to show continuous compliance with each... of 100 percent, as specified in § 63.4165(a). (5) For each capture system that is not a PTE, the data...

  11. 40 CFR 63.3930 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... record of whether the deviation occurred during a period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records... part 51 for a PTE and has a capture efficiency of 100 percent, as specified in § 63.3965(a). (5) For...

  12. 40 CFR 63.4930 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... record of whether the deviation occurred during a period of startup, shutdown, or malfunction. (2) The records in § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (3) The records... part 51 for a PTE and has a capture efficiency of 100 percent, as specified in § 63.4964(a). (5) For...

  13. Shutdown risk monitoring in TEPCO

    International Nuclear Information System (INIS)

    Sato, Hiroki; Masuda, Takahiro; Denda, Yasutaka; Yoneyama, Mitsuru; Imai, Shun-ichi; Miyata, Koichi

    2009-01-01

    At present, we are introducing risk monitors into our all three nuclear power stations; Fukushima Daiichi, Fukushima Daini and Kashiwazaki Kariwa, with technical support of TEPSYS. By monitoring shutdown risk of each unit, we are trying to optimize risks during outage inspection, and raising staff's awareness for reactor safety. This paper presents our recent shutdown risk monitoring activities in Fukushima Daiichi NPS. Shutdown risk monitoring has been carried out for the past five outages of Fukushima Daiichi NPS. Daily-changing shutdown risk is evaluated in the form of core damage frequency (CDF [/day/reactor]). We also examine high-risk point of outage plan if CDF is greater than the threshold at anytime of outage. The results are delivered to operational and maintenance staff before outage. The threshold value is set ten times as much as CDF of unit in operation. As CDF exceeds the threshold, we try to either change the system configuration, or let workers pay more attention to their works during the high-risk period. We already have some examples of outage plan modification to reduce CDF using the risk monitoring information. Greater number of station staff tends to pay more attention to shutdown risk thanks to these activities. (author)

  14. TRIGA forced shutdowns analysis

    International Nuclear Information System (INIS)

    Negut, Gheorghe; Laslau, Florica

    2008-01-01

    The need for improving the operation leads us to use new methods and strategies. Probabilistic safety assessments and statistical analysis provide insights useful for our reactor operation. This paper is dedicated to analysis of the forced shutdowns during the first reactor operation period, between 1980 to 1989. A forced shutdown data base was designed using data on forced shutdowns collected from the reactor operation logbooks. In order to sort out the forced shutdowns the records have the following fields: - current number, date, equipment failed, failure type (M for mechanical, E for electrical, D for irradiation device, U for human factor failure; - scram mode, SE for external scram, failure of reactor cooling circuits and/or irradiation devices, SR for reactor scram, exceeding of reactor nuclear parameters, SB for reactor scram by control rod drop, SM for manual scram required by the abnormal reactor status; - scram cause, giving more information on the forced shutdown. This data base was processed using DBase III. The data processing techniques are presented. To sort out the data, one of the criteria was the number of scrams per year, failure type, scram mode, etc. There are presented yearly scrams, total operation time in hours, total unavailable time, median unavailable time period, reactor availability A. There are given the formulae used to calculate the reactor operational parameters. There are shown the scrams per year in the 1980 to 1989 period, the reactor operation time per year, the reactor shutdown time per year and the operating time versus down time per year. Total number of scrams in the covered period was 643 which caused a reactor down time of 4282.25 hours. In a table the scrams as sorted on the failure type is shown. Summarising, this study emphasized some problems and difficulties which occurred during the TRIGA reactor operation at Pitesti. One main difficulty in creating this data base was the unstandardized scram record mode. Some times

  15. 40 CFR 63.3130 - What records must I keep?

    Science.gov (United States)

    2010-07-01

    ... period of startup, shutdown, or malfunction. (h) The records required by § 63.6(e)(3)(iii) through (v) related to startup, shutdown, and malfunction. (i) For each capture system that is a PTE, the data and... appendix M to 40 CFR part 51 for a PTE and has a capture efficiency of 100 percent, as specified in § 63...

  16. Program of RA reactor start-up to nominal power; Program dizanja reaktora 'RA' na nominalnu snagu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1959-07-01

    The zero start-up program is followed by the program of RA reactor start-up to nominal power. This program is desed in detail and includes the following measurements: radiation characteristics at the exit of the channels; gamma and fast neutron dose distribution in the reactor; influence of absorbers on the reactivity; temperature effect; absolute flux and calibration of ionization chambers; xenon effect; thermal and hydraulics; dosimetry around the reactor; neutron flux in the reactor core and in the reactor hall; heavy water level; thermal characteristics after shutdown. A list of measuring devices and instrumentation is included with the detailed action plan and list of responsible staff members.

  17. SP-100 initial startup and restart control strategy

    International Nuclear Information System (INIS)

    Halfen, F.J.; Wong, K.K.; Switick, D.M.; Shukla, J.N.

    1992-01-01

    This paper reports that recent Generic Flight System (GFS) updates have necessitated revisions in the initial startup and restart control strategies. The design changes that have had the most impact on the control strategies are the addition of the Auxiliary Cooling and Thaw (ACT) system for preheating the lithium filled components, changes in the reactivity worths of the reflectors and safety-rods such that initial cold criticality is achieved with only a small amount of reflector movement following the withdrawal of the safety-rods, and the removal of the scram function from the reflectors. Revised control and operating strategies have been developed and tested using the SP-100 dynamic simulation model, ARIES-GFS. The change in the total reactivity worths of the reflectors and safety-rods has eliminated the need for the use of fast and slow reflector drive speeds during the initial on-orbit approach to criticality. The relatively fast removal of the safety-rods results in a near-critical condition so that the use of slow moving (single speed) reflector drives does not add significant time to achieve full power for the initial startup. The use of the ACT system (with its NaK trace-lines for preheating and auxiliary cooling) affects the main Thermoelectric Electro-Magnetic (TEM) pump startup and the time after a shutdown before freezing occurs in the main heat transfer systems

  18. The use of neutron sources in nuclear reactors start-up after long shutdown periods

    International Nuclear Information System (INIS)

    Ponzoni Filho, P.; Borges, J.B.

    1990-01-01

    The reasons for the use of neutron sources in nuclear reactors, the different kinds of sources used and the alternatives to obtain the required minimum neutron counts in the external source range detectors after long maintenance and refueling periods are presented and discussed. The paper presents a formulation based in physics principles and experimental data, to calculate the power and time of reactor operation required to increase the effective fluence of secondary neutron sources. The option of using actinides produced during operation of the reactor as an additional source of neutrons is also discussed in depth to allow similar calculations in other kinds of reactors. The re-utilization of primary sources is considered as a last option. (author)

  19. Enhancing Efficiency of Safeguards at Facilities that are Shutdown or Closed-Down, including those being Decommissioned

    Energy Technology Data Exchange (ETDEWEB)

    Moran, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stern, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Colley, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marzo, M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-12-15

    International Atomic Energy Agency (IAEA) safeguards involves verification activities at a wide range of facilities in a variety of operational phases (e.g., under construction, start-up, operating, shutdown, closed-down, and decommissioned). Safeguards optimization for each different facility type and operational phase is essential for the effectiveness of safeguards implementation. The IAEA’s current guidance regarding safeguards for the different facility types in the various lifecycle phases is provided in its Design Information Examination (DIE) and Verification (DIV) procedure. 1 Greater efficiency in safeguarding facilities that are shut down or closed down, including those being decommissioned, could allow the IAEA to use a greater portion of its effort to conduct other verification activities. Consequently, the National Nuclear Security Administration’s Office of International Nuclear Safeguards sponsored this study to evaluate whether there is an opportunity to optimize safeguards approaches for facilities that are shutdown or closed-down. The purpose of this paper is to examine existing safeguards approaches for shutdown and closed-down facilities, including facilities being decommissioned, and to seek to identify whether they may be optimized.

  20. 76 FR 80358 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Science.gov (United States)

    2011-12-23

    ..., no capital/startup costs, and $719,100 in operation and maintenance (O&M) costs. Changes in the... of any startup, shutdown, or malfunction in the operation of an affected facility, or any period... there are no new sources with reporting requirements, no capital/startup costs are incurred. The only...

  1. Physicochemical characteristics and microbial community evolution of biofilms during the start-up period in a moving bed biofilm reactor.

    Science.gov (United States)

    Zhu, Yan; Zhang, Yan; Ren, Hong-Qiang; Geng, Jin-Ju; Xu, Ke; Huang, Hui; Ding, Li-Li

    2015-03-01

    This study aimed to investigate biofilm properties evolution coupled with different ages during the start-up period in a moving bed biofilm reactor system. Physicochemical characteristics including adhesion force, extracellular polymeric substances (EPS), morphology as well as volatile solid and microbial community were studied. Results showed that the formation and development of biofilms exhibited four stages, including (I) initial attachment and young biofilm formation, (II) biofilms accumulation, (III) biofilm sloughing and updating, and (IV) biofilm maturation. During the whole start-up period, adhesion force was positively and significantly correlated with the contents of EPS, especially the content of polysaccharide. In addition, increased adhesion force and EPS were beneficial for biofilm retention. Gram-negative bacteria mainly including Sphaerotilus, Zoogloea and Haliscomenobacter were predominant in the initial stage. Actinobacteria was beneficial to resist sloughing. Furthermore, filamentous bacteria were dominant in maturation biofilm. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Startup and commissioning of pressurized water reactors

    International Nuclear Information System (INIS)

    Albert, L.J.; Gilbert, C.F.

    1983-05-01

    A critical phase of plant development is the test, startup, and commissioning period. The effort expended prior to commissioning has a definite effect on the reliability and continuing availability of the plant during its life. This paper describes a test, startup, and commissioning program for a pressurized water reactor (PWR) plant. This program commences with the completion of construction and continues through the turnover of equipment/systems to the owner's startup/ commissioning group. The paper addresses the organization of the test/startup group, planning and scheduling, test procedures and initial testing, staffing and certification of the test group, training of operators, and turnover to the owner

  3. Dioxins from medical waste incineration: Normal operation and transient conditions.

    Science.gov (United States)

    Chen, Tong; Zhan, Ming-xiu; Yan, Mi; Fu, Jian-ying; Lu, Sheng-yong; Li, Xiao-dong; Yan, Jian-hua; Buekens, Alfons

    2015-07-01

    Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are key pollutants in waste incineration. At present, incinerator managers and official supervisors focus only on emissions evolving during steady-state operation. Yet, these emissions may considerably be raised during periods of poor combustion, plant shutdown, and especially when starting-up from cold. Until now there were no data on transient emissions from medical (or hospital) waste incineration (MWI). However, MWI is reputed to engender higher emissions than those from municipal solid waste incineration (MSWI). The emission levels in this study recorded for shutdown and start-up, however, were significantly higher: 483 ± 184 ng Nm(-3) (1.47 ± 0.17 ng I-TEQ Nm(-3)) for shutdown and 735 ng Nm(-3) (7.73 ng I-TEQ Nm(-3)) for start-up conditions, respectively. Thus, the average (I-TEQ) concentration during shutdown is 2.6 (3.8) times higher than the average concentration during normal operation, and the average (I-TEQ) concentration during start-up is 4.0 (almost 20) times higher. So monitoring should cover the entire incineration cycle, including start-up, operation and shutdown, rather than optimised operation only. This suggestion is important for medical waste incinerators, as these facilities frequently start up and shut down, because of their small size, or of lacking waste supply. Forthcoming operation should shift towards much longer operating cycles, i.e., a single weekly start-up and shutdown. © The Author(s) 2015.

  4. Model based analysis of the time scales associated to pump start-ups

    Energy Technology Data Exchange (ETDEWEB)

    Dazin, Antoine, E-mail: antoine.dazin@lille.ensam.fr [Arts et métiers ParisTech/LML Laboratory UMR CNRS 8107, 8 bld Louis XIV, 59046 Lille cedex (France); Caignaert, Guy [Arts et métiers ParisTech/LML Laboratory UMR CNRS 8107, 8 bld Louis XIV, 59046 Lille cedex (France); Dauphin-Tanguy, Geneviève, E-mail: genevieve.dauphin-tanguy@ec-lille.fr [Univ Lille Nord de France, Ecole Centrale de Lille/CRISTAL UMR CNRS 9189, BP 48, 59651, Villeneuve d’Ascq cedex F 59000 (France)

    2015-11-15

    Highlights: • A dynamic model of a hydraulic system has been built. • Three periods in a pump start-up have been identified. • The time scales of each period have been estimated. • The parameters affecting the rapidity of a pump start-up have been explored. - Abstract: The paper refers to a non dimensional analysis of the behaviour of a hydraulic system during pump fast start-ups. The system is composed of a radial flow pump and its suction and delivery pipes. It is modelled using the bond graph methodology. The prediction of the model is validated by comparison to experimental results. An analysis of the time evolution of the terms acting on the total pump pressure is proposed. It allows for a decomposition of the start-up into three consecutive periods. The time scales associated with these periods are estimated. The effects of parameters (angular acceleration, final rotation speed, pipe length and resistance) affecting the start-up rapidity are then explored.

  5. Startup program after SGR and power increase

    International Nuclear Information System (INIS)

    Krajnc, B.; Dudas, M.; Spiler, J.; Novsak, M.

    2000-01-01

    NPP Krsko replaced steam generators during the outage 2000. Parallel with the steam generator replacement all required systems modifications to accommodate new steam generators into the existing plant (upper feed,..) and support plant power increase of 6.3%, have been implemented. During the years 1997 - 2000 all the required licensing, technical analyses and systems verifications to support such plant changes have been completed. One of the activities within this effort was also the preparation of a detailed Plant Startup Program, which was subject of licensing review and approval process. An integrated plant startup program was then developed based on the plant startup test program, performed regularly during plant startup after refueling and above-mentioned Plant Startup Program. These additional tests defined by the Startup Test Program have been required due to new steam generators, steam generator replacement and related modifications, and power increase from previous 1882 MWt to 2000 MWt. During the preparation period, a startup team was established and procedures were written. All procedures sensitive to the operation were validated on the plant specific simulator. This paper presents more about the Startup Test Program, analysis of its implementation, the results of some key tests as well as the lessons learned. (author)

  6. 40 CFR 63.4352 - How do I demonstrate continuous compliance with the emission limitations?

    Science.gov (United States)

    2010-07-01

    ..., the efficiency of the capture system is 100 percent, and you achieved the operating limits required by...) [Reserved] (h) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup... Administrator will determine whether deviations that occur during a period of startup, shutdown, or malfunction...

  7. Safety considerations for research reactors in extended shutdown

    International Nuclear Information System (INIS)

    2004-01-01

    According to the IAEA Research Reactor Database, in the last 20 years, 367 research reactors have been shut down. Of these, 109 have undergone decommissioning and the rest are in extended shutdown with no clear definition about their future. Still other research reactors are infrequently operated with no meaningful utilization programme. These two situations present concerns related to safety such as loss of corporate memory, personnel qualification, maintenance of components and systems and preparation and maintenance of documentation. There are many reasons to shut down a reactor; these may include: - the need to carry out modifications in the reactor systems; - the need for refurbishment to extend the lifetime of the reactor; - the need to repair reactor structures, systems, or components; - the need to remedy technical problems; - regulatory or public concerns; - local conflicts or wars; - political convenience; - the lack of resources. While any one of these reasons may lead to shutdown of a reactor, each will present unique problems to the reactor management. The large variations from one research reactor to the next also will contribute to the uniqueness of the problems. Any option that the reactor management adopts will affect the future of the facility. Options may include dealing with the cause of the shutdown and returning to normal operation, extending the shutdown period waiting a future decision, or decommissioning. Such options are carefully and properly analysed to ensure that the solution selected is the best in terms of reactor type and size, period of shutdown and legal, economic and social considerations. This publication provides information in support of the IAEA safety standards for research reactors

  8. Nuclear reactor unit shutdown planning

    International Nuclear Information System (INIS)

    Gardais, J.P.

    1994-01-01

    In order to optimize the reactor maintenance shutdown efficiency and the reactor availability, an audit had been performed on the shutdown organization at EDF: management, skills, methods and experience feedback have been evaluated; several improvement paths have been identified: project management, introduction of shutdown management professionals, shutdown permanent industrialization, and experience feedback engineering

  9. Process for start-up and slack period operation of fully charged boilers, e. g. of coal pressure gasification plants, and boiler system to carry out the process

    Energy Technology Data Exchange (ETDEWEB)

    Meyer-Kahrweg, H

    1978-10-19

    For the start-up and slack period of fully charged boilers hot water of e.g. 180/sup 0/C from a high pressure heater which is fed by a start-up boiler is used. In the first instance the boiler, its preheater and the vaporizer are filled with hot water from the start-up boiler until a medium water level is obtained. Subsequently water from the water separator is recycled through the preheater and the boiler by forced circulation and it is heated up to the hot water temperature by the start-up boiler. After the desired temperature has been reached the pressure combustion is ignited and the circulation through the preheater is interrupted by reversing to direct feed back. A considerable shortening of the start-up time is achieved because no heat is released to the condensation water in the boiler system as is done usually.

  10. Fire damp gas in a heavy water reactor; Praskavi gas u teskovodnom reaktoru

    Energy Technology Data Exchange (ETDEWEB)

    Nikolic, V D [Institute of Nuclear Sciences Boris Kidric, Reaktor RA, Vinca, Beograd (Yugoslavia)

    1963-07-01

    This document describes the process of fire damp gas creation in the reactor core and dependence of the gas percentage on the temperature, i.e. reactor power. It contains a detailed plan for measuring the the percent of fire damp gas at the RA reactor: before start-up, after longer shut-down periods, immediately after safety shutdown, periodically during operation campaign.

  11. Supplementary shutdown system of 220 MWe standard PHWR in India

    International Nuclear Information System (INIS)

    Muktibodh, U.C.

    1997-01-01

    The design objective of the shutdown system is to make the reactor subcritical and hold it in that state for an extended period of time. This objective must be realised under all anticipated operational occurrences and postulated abnormal conditions even during most reactive state of the core. PHWR design criteria for shutdown stipulates requirement of two independent diverse and fast acting shutdown systems, either of which acting alone should meet the above objectives. This requirement would normally call for a large number of reactivity mechanism penetrations into the calandria. From the point of view of space availability at the reactivity mechanism area on top of calandria, for the relatively small core of 220 MWe PHWRs, and ease of maintenance realisation of the total worth by either of the shutdown systems acting alone was difficult. To overcome this engineering constraint and at the same time to satisfy the design criteria, a unique approach to meet the reactivity demands for shutdown was adopted. The reactivity requirements of the shutdown consists of fast and slow reactivity changes. For the shutdown system of 220 MWe PHWRs, the approach of realizing fast reactivity changes with dual redundant, diverse, fast acting shutdown systems aided by a slow acting shutdown system to counter delayed reactivity changes was conceived. The supplementary slow acting shutdown system is called upon to act after actuation of either of the two redundant fast acting systems and is referred to as Liquid Poison Injection System (LPIS). The system adds bulk amount of neutron poison (boric acid), equivalent to 45 mk, directly into the moderator through two nozzles in calandria using pneumatic pressure. This paper describes the design of LPIS as envisaged for the standardised 220 MWe PHWRs. (author)

  12. Shutdown Safety in NEK

    International Nuclear Information System (INIS)

    Gluhak, Mario; Senegovic, Marko

    2014-01-01

    Industry performance analysis since 2004 has revealed that 23% of the events reported to WANO occurred during outage periods. Given the fact that a plant is in the outage only 5 percent of the time, this emphasizes the importance of shutdown safety and measures station staffs undertake to maintain effective barriers to safety margins during the outage. Back in 1990s, the industry adopted guidance to meet safety requirements by focusing on safety functions. Both WANO and INPO released various documents, reports and guidelines to help accomplish those requirements. However, in the last decade inadequate 'defence in depth' has led to several events affecting shutdown safety and challenging one of the most important nuclear safety principles: 'The special characteristics of nuclear technology are taken into account in all decisions and actions. Reactivity control, continuity of core cooling, and integrity of fission product barriers are valued as essential, distinguishing attributes of nuclear station work environment'. NEK has recognized the importance of 'defence in depth'Industry performance analysis since 2004 has revealed that 23% of the events reported to WANO occurred during outage periods. Given the fact that a plant is in the outage only 5 percent of the time, this emphasizes the importance of shutdown safety and measures station staffs undertake to maintain effective barriers to safety margins during the outage. Back in 1990s, the industry adopted guidance to meet safety requirements by focusing on safety functions. Both WANO and INPO released various documents, reports and guidelines to help accomplish those requirements. However, in the last decade inadequate 'defence in depth' has led to several events affecting shutdown safety and challenging one of the most important nuclear safety principles: 'The special characteristics of nuclear technology are taken into account in all decisions and actions. Reactivity

  13. CANDU passive shutdown systems

    Energy Technology Data Exchange (ETDEWEB)

    Hart, R S; Olmstead, R A [AECL CANDU, Sheridan Park Research Community, Mississauga, ON (Canada)

    1996-12-01

    CANDU incorporates two diverse, passive shutdown systems, independent of each other and from the reactor regulating system. Both shutdown systems function in the low pressure, low temperature, moderator which surrounds the fuel channels. The shutdown systems are functionally different, physically separate, and passive since the driving force for SDS1 is gravity and the driving force for SDS2 is stored energy. The physics of the reactor core itself ensures a degree of passive safety in that the relatively long prompt neutron generation time inherent in the design of CANDU reactors tend to retard power excursions and reduces the speed required for shutdown action, even for large postulated reactivity increases. All passive systems include a number of active components or initiators. Hence, an important aspect of passive systems is the inclusion of fail safe (activated by active component failure) operation. The mechanisms that achieve the fail safe action should be passive. Consequently the passive performance of the CANDU shutdown systems extends beyond their basic modes of operation to include fail safe operation based on natural phenomenon or stored energy. For example, loss of power to the SDS1 clutches results in the drop of the shutdown rods by gravity, loss of power or instrument air to the injection valves of SDS2 results in valve opening via spring action, and rigorous self checking of logic, data and timing by the shutdown systems computers assures a fail safe reactor trip through the collapse of a fluctuating magnetic field or the discharge of a capacitor. Event statistics from operating CANDU stations indicate a significant decrease in protection system faults that could lead to loss of production and elimination of protection system faults that could lead to loss of protection. This paper provides a comprehensive description of the passive shutdown systems employed by CANDU. (author). 4 figs, 3 tabs.

  14. Variation of the Effectiveness of Hydrogen Water Chemistry in a Boiling Water Reactor during Startup Operations

    International Nuclear Information System (INIS)

    Yeh, Tsung-Kuang; Wang, Mei-Ya

    2012-09-01

    For mitigating intergranular stress corrosion cracking (IGSCC) in an operating boiling water reactor (BWR), the technology of hydrogen water chemistry (HWC) aiming at coolant chemistry improvement has been adopted worldwide. However, the hydrogen injection system employed in this technology was designed to operate only at power levels greater than 30% of the rated power or at coolant temperatures of greater than 450 deg. F. This system is usually in an idle and standby mode during a startup operation. The coolant in a BWR during a cold shutdown normally contains a relatively high level of dissolved oxygen from intrusion of atmospheric air. Accordingly, the structural materials in the primary coolant circuit (PCC) of a BWR could be exposed to a strongly oxidizing environment for a short period of time during a subsequent startup operation. At some plants, the feasibility of hydrogen water chemistry during startup operations has been studied, and its effectiveness on suppressing SCC initiation was evaluated. It is technically difficult to directly procure water chemistry data at various locations of an operating reactor. Accordingly, the impact of startup operation on water chemistry in the PCC of a BWR operating under normal water chemistry (NWC) or HWC can only be theoretically evaluated through computer modelling. In this study, a well-developed computer code DEMACE was used to investigate the variations in redox species concentration and in electrochemical corrosion potential (ECP) of components in the PCC of a domestic BWR during startup operations in the presence of HWC. Simulations were carried out for [H2] FW s ranging from 0.0 to 2.0 parts per million (ppm) and for power levels ranging from 2.5% to 11.3% during startup operations. Our analyses indicated that for power levels with steam generation in the core, a higher power level would tend to promote a more oxidizing coolant environment for the structural components and therefore lead to less HWC

  15. Morphological study of biomass during the start-up period of a fixed-bed anaerobic reactor treating domestic sewage

    OpenAIRE

    Lima,Cláudio Antonio Andrade; Ribeiro,Rogers; Foresti,Eugenio; Zaiat,Marcelo

    2005-01-01

    This work focused on a morphological study of the microorganisms attached to polyurethane foam matrices in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor treating domestic sewage. The experiments consisted of monitoring the biomass colonization process of foam matrices in terms of the amount of retained biomass and the morphological characteristics of the cells attached to the support during the start-up period. Non-fluorescent rods and cocci were found to predominate in the p...

  16. Analysis of HFETR shut-down state caused by loss of off-site power supply

    International Nuclear Information System (INIS)

    Wang Jinghu

    1997-01-01

    During the last 15 years, there are more than 40 unplanned shut-downs caused by loss of off-site power in HFETR. Because HFETR is a special research reactor, the author describes the shut-down state as three period. The author also discusses the influence of the number of shut-down due to loss of off-site power supply on the reactor safety, and propose some suggestions and measures to reduce the effects

  17. Probabilistic analysis of 900 MWe PWR. Shutdown technical specifications

    International Nuclear Information System (INIS)

    Mattei, J.M.; Bars, G.

    1987-11-01

    During annual shutdown, preventive maintenance and modifications which are made on PWRs cause scheduled unavailabilities of equipment or systems which might harm the safety of the installation, in spite of the low level of decay heat during this period. The pumps in the auxiliary feedwater system, component cooling water system, service water system, the water injection arrays (LPIS, HPIS, CVCS), and the containment spray system may have scheduled unavailability, as well as the power supply of the electricity boards. The EDF utility is aware of the risks related to these situations for which accident procedures have been set up and hence has proposed limiting downtime for this equipment during the shutdown period, through technical specifications. The project defines the equipment required to ensure the functions important for safety during the various shutdown phases (criticality, water inventory, evacuation of decay heat, containment). In order to be able to judge the acceptability of these specifications, the IPSN, the technical support of the Service Central de Surete des Installations Nucleaires, has used probabilistic methodology to analyse the impact on the core melt probability of these specifications, for a French 900 MWe PWR

  18. Inventory of radioactive corrosion products on the primary surfaces and release during shutdown in Ringhals 2

    International Nuclear Information System (INIS)

    Aronsson, O.

    1994-01-01

    In Ringhals 2 a retrospective study using gamma scans of system surfaces, fuel crud sampling and reactor coolant analyses during operation and shutdown has been done. The data have been used to prepare a balance of activity inventory. The inventory has been fairly stable from 1986 to 1993, expressed as a gamma source term. The steam generator replacement in 1989 removed some 40-50% of the Co-60 inventory in the reactor system. After the steam generator replacement, the gamma source term has got an increasing contribution from Co-58, absolutely as well as relatively. The reason for this is probably the switch from high pH operation to modified pH operation. Corrosion from fresh alloy 690 surfaces in the new steam generators is probably another contributing factor. The inventory and production rate of Co-60 is decreasing over the years. It has also been found that clean-up of the reactor coolant during start-up, operation, and shutdown as well as the fuel pool during refuelling removes about the same amounts of Co-60. (author). 11 figs., 15 refs

  19. Open innovation and the comparison between startups and incumbent firms in Spain

    DEFF Research Database (Denmark)

    Gimenez Fernandez, Elena Maria; Beukel, Karin

    2017-01-01

    This study compares the open innovation strategy between startups and incumbent firms over a period of ten years (2004-2013). Using a sample of startups and incumbent Spanish firms, we find that they differ considerably, and that this has implications for management. Incumbent firms and startups...... differ in terms of their use of external cooperation activities as a source of innovation. The lack of financial and human resources of startups leads them to open their borders more than incumbent firms, and startups benefit from being flexible, as they have yet to implement routines. This boosts...... startups’ innovation performance....

  20. On the experience of the start-up measurements at the Temelin Unit 1 with TVSA-T fresh fuel loading. PowerPoint presentation

    International Nuclear Information System (INIS)

    Krajnov, Yu.A.; Kravchenko, A.A.; Pinegin, A.A.; Spirkin, E.I.; Tsyganov, S.V.; Molchanov, V.L.; Mecir, V.; Milisdoerfer, L.; Durdak, Z.

    2010-01-01

    The purpose was to demonstrate compliance with the core design parameters and safety analyses and assess the results against safety criteria (compare the true values with the limiting levels used in safety analysis), design criteria (compare the true and predicted values), and realization criteria (confirm the test realization based on an approved procedure and acquisition of data necessary for its evaluation). Theoretical data were obtained by the KASKAD method. The experimental equipment is described with focus on the Physics Startup Control Board. The following experimental results are described: first criticality; symmetry assessment; isothermal temperature coefficient and moderator temperature coefficient (ITC, MTC); single bank worth; differential and integral worth boron reactivity coefficients; and emergency shutdown efficiency. It is concluded that despite problems that occurred and were assessed during the start-up, the test results demonstrated acceptability of further operation; the start-up test results demonstrated compliance with core design parameters and safety analyses, and therefore the operation is safe. (P.A.)

  1. Start-up of a drinking water biofilter

    DEFF Research Database (Denmark)

    Ramsay, Loren; Søborg, Ditte; Breda, Inês Lousinha Ribeiro

    When virgin filter media is placed in drinking water biofilters, a start-up period of some months typically ensues. During this period, the necessary inorganic coating and bacterial community are established on the filter medium, after which the treated water complies with drinking water criteria...

  2. Business Startups: An analysis of selection and post-startup performance (Japanese)

    OpenAIRE

    YASUDA Takehiko

    2010-01-01

    This paper investigates how the pre-startup circumstances surrounding an entrepreneur, during the time when he or she decides to start a business, affects the post-startup performance. Based on the original dataset, sample selection models are estimated connecting nascent entrepreneurs' selection of a startup with actual entrepreneurs' performance post-startup. The results of this paper confirm that the individual attributes of nascent entrepreneurs, which make it easier (difficult) to decide...

  3. 40 CFR 60.4244 - What test methods and other procedures must I use if I am an owner or operator of a stationary SI...

    Science.gov (United States)

    2010-07-01

    ... 100 percent peak (or the highest achievable) load and according to the requirements in § 60.8 and... performance tests during periods of startup, shutdown, or malfunction, as specified in § 60.8(c). If your stationary SI internal combustion engine is non-operational, you do not need to startup the engine solely to...

  4. 40 CFR 60.482-1a - Standards: General.

    Science.gov (United States)

    2010-07-01

    ... startup. (b) Compliance with §§ 60.482-1a to 60.482-10a will be determined by review of records and... in VOC service only during startup and shutdown, excluding startup and shutdown between batches of... 100...

  5. Start-up of Rapsodie

    International Nuclear Information System (INIS)

    Pontier, R.

    1967-01-01

    After giving a general description of Rapsodie this report presents the conditions in which the start-up occurred and in which the tests were carried out. A chronological account is given of the operations and of the main events which occurred. The modifications made to the reactor during this period are described and a synthesis of the results obtained is presented. (author) [fr

  6. Experimental study on the start-up with dry gases from normal cell temperatures in self-humidified proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Kong, Im Mo; Jung, Aeri; Kim, Beom Jun; Baik, Kyung Don; Kim, Min Soo

    2015-01-01

    In this study, the start-up characteristics of PEMFCs (proton exchange membrane fuel cells) was investigated with dry gases from normal cell temperatures above 0 °C. Firstly, the effects of flow arrangements (co-flow and counter-flow) were evaluated at a starting cell temperature of 25 °C. Then, the start-up was successful in both arrangements, but it showed better performance with counter-flow. In addition, the hydrogen concentration was measured and it showed that hydrogen crossover contributes to the membrane hydration and the first phase of dry start-up. However, although the cell temperature rose above 45 °C after start-up form 25 °C with counter-flow arrangement, the restart-up after shut-down failed at a starting cell temperature of 45 °C regardless of flow arrangements. Considering the needs of restart-up, the available starting cell temperature should be improved. For this, after first sub-step of start-up process, relatively low flow rates were maintained to retain produced water without purge so that the membrane can be hydrated sufficiently. With this modified process, denominated as WSP (water storage process) in this study, the dry start-up became successful at a starting cell temperature of 45 °C and the cell performance was remarkably improved especially with counter-flow arrangement. - Highlights: • Start-up with dry gases from normal cell temperatures was investigated. • Counter-flow arrangement showed better performance over co-flow arrangement. • Water is produced by hydrogen crossover and its direct reaction with oxygen at cathode side. • It prevents the membrane dehydration and helps the start-up during the first phase of the process. • Available starting cell temperature and cell performance could be improved with WSP.

  7. Software Startups - A Research Agenda

    Directory of Open Access Journals (Sweden)

    Michael Unterkalmsteiner

    2016-10-01

    Full Text Available Software startup companies develop innovative, software-intensive products within limited time frames and with few resources, searching for sustainable and scalable business models. Software startups are quite distinct from traditional mature software companies, but also from micro-, small-, and medium-sized enterprises, introducing new challenges relevant for software engineering research. This paper's research agenda focuses on software engineering in startups, identifying, in particular, 70+ research questions in the areas of supporting startup engineering activities, startup evolution models and patterns, ecosystems and innovation hubs, human aspects in software startups, applying startup concepts in non-startup environments, and methodologies and theories for startup research. We connect and motivate this research agenda with past studies in software startup research, while pointing out possible future directions. While all authors of this research agenda have their main background in Software Engineering or Computer Science, their interest in software startups broadens the perspective to the challenges, but also to the opportunities that emerge from multi-disciplinary research. Our audience is therefore primarily software engineering researchers, even though we aim at stimulating collaborations and research that crosses disciplinary boundaries. We believe that with this research agenda we cover a wide spectrum of the software startup industry current needs.

  8. 40 CFR 60.334 - Monitoring of operations.

    Science.gov (United States)

    2010-07-01

    ..., the data acquisition and handling system must calculate and record the hourly NOX emissions in the...). Excess emissions shall be reported for all periods of unit operation, including startup, shutdown and...

  9. Management of the interfaces between construction and startup

    International Nuclear Information System (INIS)

    Anderson, W.R.; Beatty, D.C.

    1976-01-01

    Many papers have been presented, and many articles published on the various tasks of Nuclear Plant Design, Construction, Startup and Operations. Most of the presentations have been concerned with the complexities of the particular task being discussed. This is as it should be, since these areas are quite broad in themselves and deserve the full attention of the technology. Recently more attention is being directed to the interfaces between the classical portions of nuclear projects. The paper attempts to address just one of these areas: the interfaces between construction and startup. These interfaces have normally been addressed to the extent that engineering schedules, construction schedules, equipment deliveries and startup test schedules have been dovetailed graphically, or computerized, and periodically updated to reflect significant changes

  10. Start-up of a UASB effluent treatment plant on distillery wastewater ...

    African Journals Online (AJOL)

    This paper reports on the seasonal operation of a UASB treatment plant treating a distillery wastewater stream with particular focus on seasonal start-up conditions after the first process commissioning. The start-up period was typically one week before process stability could be achieved. It is recommended that the loading ...

  11. MODEL OF IT-STARTUPS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Ольга Андреевна КОЗИНА

    2017-03-01

    Full Text Available Decrease mortality of startups during first three years of existing is an important task of the economy of any country. It has been established that the existing methods of enterprise management have some disadvantages or limits for using in IT-startups management. Analysis of mortality reasons of startups in different stages of their life cycle has been carried out. The comparing of reasons why startups in different time intervals, in different areas of them functioning are failure showed that the run out of cash and the use of not viable business model have appeared mortality factors most often denoted by ex-leaders of startups. The model of startup management based on the lean startup model has been developed. Steps for the management of startups along first two stages of their life cycle were added. We noted that it is important to select set of static points and changeable points of startup during the process of formulation of the business model. Steps to reduce the number of iterations in the method of the lean startup are proposed.

  12. 40 CFR 63.6120 - What performance tests and other procedures must I use?

    Science.gov (United States)

    2010-07-01

    ... tests or compliance evaluations during periods of startup, shutdown, or malfunction. Performance tests must be conducted at high load, defined as 100 percent plus or minus 10 percent. (d) You must conduct...

  13. Startup development: strategic point of view

    OpenAIRE

    ZOPUNYAN Y.S.

    2015-01-01

    The article analyses different strategies of the startup development. The author considers such phases of the startup development as pre-startup, launch, post-startup. The author analyzes factors that affect startup development. The paper presents conclusions about key elements of startup's strategic development.

  14. Reactor shutdown device

    International Nuclear Information System (INIS)

    Inoue, Toyokazu.

    1982-01-01

    Purpose: To obtain a highly reliable reactor shutdown device capable of checking its function irrespective of the state whether shutdown or operation in a gas-cooled type reactor. Constitution: A hopper is disposed above a guide tube inserted into the reactor core and particulate neutron absorbers are contained in the hopper. An opening for falling particles is disposed to the bottom of the hopper in opposition to the upper end of the guide pipe and the opening is closed by a plug suspended by way of a weld line so as to be capable of dropping. A power source for supplying electrical current to the weld line is disposed. Accordingly, if the current is supplied to the weld line, the line is cut by welding to fall the plug so that the neutron-absorbing particles fall from the opening into the guide pipe to shutdown the reactor, whereby high reliability is obtained for the operation. (Seki, T.)

  15. 40 CFR 65.112 - Standards: Compressors.

    Science.gov (United States)

    2010-07-01

    ... the compressor stuffing box pressure at all times (except during periods of start-up, shutdown, or... process stream. (c) Barrier fluid system. The barrier fluid shall not be in light liquid service. Each...

  16. Tokamak reactor systems studies

    International Nuclear Information System (INIS)

    1992-01-01

    A summary of work completed on the ARIES project during this report period is given. The main areas of effort were: neutronics, shield optimization and design, safety, systems, startup and shutdown, and ripple loss

  17. Critical Incidents of Growth in Nordic eHealth Service Start-Ups

    Directory of Open Access Journals (Sweden)

    Martti Saarela

    2017-06-01

    Full Text Available Digitalisation can revolutionise healthcare delivery and provide new business opportunities for innovative start-ups. Start-up businesses in the healthcare service sector are a promising source of new employment and innovations. The start-up stage is the most critical period for the survival of a business, as decisions made during the early stages have a definitive influence on success. This study seeks to clarify the early development of eHealth service start-ups. To summarise the research problem, the authors ask the following question: What are the critical incidents related to the early development of eHealth service start-ups? The units of analysis in this study are 14 Nordic eHealth service start-ups located in Sweden and Finland. The Critical Incident Technique (CIT and semi-structured interviews were applied for data collection. The results are of interest to the public sector, which plays an essential role in healthcare as a service producer, but also as a creator of the business conditions of and opportunities for small businesses.

  18. Shutdown Chemistry Process Development for PWR Primary System

    Energy Technology Data Exchange (ETDEWEB)

    Sung, K.B. [Korea Electric Power Research Institute, Taejeon (Korea, Republic of)

    1997-12-31

    This study report presents the shutdown chemistry of PWR primary system to reduce and remove the radioactive corrosion products which were deposited on the nuclear fuel rods surface and the outside of core like steam generator channel head, RCS pipings etc. The major research results are the follows ; the deposition radioactive mechanism of corrosion products, the radiochemical composition, the condition of coolant chemistry to promote the dissolution of radioactive cobalt and nickel ferrite, the control method of dissolved hydrogen concentration in the coolant by the mechanical and chemical methods. The another part of study is to investigate the removal characteristics of corrosion product ions and particles by the demineralization system to suggest the method which the system could be operate effectively in shut-down purification period. (author). 19 refs., 25 figs., 48 tabs.

  19. Improvements of primary coolant shutdown chemistry and reactor coolant system cleanup

    International Nuclear Information System (INIS)

    Gaudard, G.; Gilles, B.; Mesnage, F.; Cattant, F.

    2002-01-01

    In the framework of a radiation exposure management program entitled >, EDF aims at decreasing the mass dosimetry of nuclear power plants workers. So, the annual dose per unit, which has improved from 2.44 m.Sv in 1991 to 1.08 in 2000, should target 0.8 mSv in the year 2005 term in order to meet the results of the best nuclear operators. One of the guidelines for irradiation source term reduction is the optimization of operation parameters, including reactor coolant system (RCS) chemistry in operation, RCS shutdown chemistry and RCS cleanup improvement. This paper presents the EDF strategy for the shutdown and start up RCS chemistry optimization. All the shutdown modes have been reviewed and for each of them, the chemical specifications will be fine tuned. A survey of some US PWRs shutdown practices has been conducted for an acid and reducing shutdown chemistry implementation test at one EDF unit. This survey shows that deviating from the EPRI recommended practice for acid and reducing shutdown chemistry is possible and that critical path impact can be minimized. The paper also presents some investigations about soluble and insoluble species behavior and characterization; the study focuses here on 110m Ag, 122 Sb, 124 Sb and iodine contamination. Concerning RCS cleanup improvement, the paper presents two studies. The first one highlights some limited design modifications that are either underway or planned, for an increased flow rate during the most critical periods of the shutdown. The second one focuses on the strategy EDF envisions for filters and resins selection criteria. Matching the study on contaminants behavior with the study of filters and resins selection criteria should allow improving the cleanup efficiency. (authors)

  20. 40 CFR 60.482-1 - Standards: General.

    Science.gov (United States)

    2010-07-01

    ... of initial startup. (b) Compliance with §§ 60.482-1 to 60.482-10 will be determined by review of... only during startup and shutdown, excluding startup and shutdown between batches of the same campaign... Three quarters Semiannually. 75 to 100 Monthly Quarterly Semiannually. (2) Pumps and valves that are...

  1. Shutdown and low-power operation at commercial nuclear power plants in the United States

    International Nuclear Information System (INIS)

    1993-09-01

    The report contains the results of the NRC Staff's evaluation of shutdown and low-power operations at US commercial nuclear power plants. The report describes studies conducted by the staff in the following areas: Operating experience related to shutdown and low-power operations, probabilistic risk assessment of shutdown and low-power conditions and utility programs for planning and conducting activities during periods the plant is shut down. The report also documents evaluations of a number of technical issues regarding shutdown and low-power operations performed by the staff, including the principal findings and conclusions. Potential new regulatory requirements are discussed, as well as potential changes in NRC programs. A draft report was issued for comment in February 1992. This report is the final version and includes the responses to the comments along with the staff regulatory analysis of potential new requirements

  2. FPGA based computation of average neutron flux and e-folding period for start-up range of reactors

    International Nuclear Information System (INIS)

    Ram, Rajit; Borkar, S.P.; Dixit, M.Y.; Das, Debashis

    2013-01-01

    Pulse processing instrumentation channels used for reactor applications, play a vital role to ensure nuclear safety in startup range of reactor operation and also during fuel loading and first approach to criticality. These channels are intended for continuous run time computation of equivalent reactor core neutron flux and e-folding period. This paper focuses only the computational part of these instrumentation channels which is implemented in single FPGA using 32-bit floating point arithmetic engine. The computations of average count rate, log of average count rate, log rate and reactor period are done in VHDL using digital circuit realization approach. The computation of average count rate is done using fully adaptive window size moving average method, while Taylor series expansion for logarithms is implemented in FPGA to compute log of count rate, log rate and reactor e-folding period. This paper describes the block diagrams of digital logic realization in FPGA and advantage of fully adaptive window size moving average technique over conventional fixed size moving average technique for pulse processing of reactor instrumentations. (author)

  3. Magnetic disconnect for secondary shutdown

    International Nuclear Information System (INIS)

    Lessor, D.L.

    1972-01-01

    A description is given of studies to develop a magnetic holding clutch in the control rod drive line as an alternate shutdown device for the FFTF. Results indicate that a three-phase disconnect, hold, and backup shutdown system can be designed to operate satisfactorily. (U.S.)

  4. An enhanced tokamak startup model

    Science.gov (United States)

    Goswami, Rajiv; Artaud, Jean-François

    2017-01-01

    The startup of tokamaks has been examined in the past in varying degree of detail. This phase typically involves the burnthrough of impurities and the subsequent rampup of plasma current. A zero-dimensional (0D) model is most widely used where the time evolution of volume averaged quantities determines the detailed balance between the input and loss of particle and power. But, being a 0D setup, these studies do not take into consideration the co-evolution of plasma size and shape, and instead assume an unchanging minor and major radius. However, it is known that the plasma position and its minor radius can change appreciably as the plasma evolves in time to fill in the entire available volume. In this paper, an enhanced model for the tokamak startup is introduced, which for the first time takes into account the evolution of plasma geometry during this brief but highly dynamic period by including realistic one-dimensional (1D) effects within the broad 0D framework. In addition the effect of runaway electrons (REs) has also been incorporated. The paper demonstrates that the inclusion of plasma cross section evolution in conjunction with REs plays an important role in the formation and development of tokamak startup. The model is benchmarked against experimental results from ADITYA tokamak.

  5. Optimal relations of the parameters ensuring safety during reactor start-up

    International Nuclear Information System (INIS)

    Yurkevich, G.P.

    2004-01-01

    Procedure and equations for the determination of optimal ratio between parameters allowing safe removal of reactor in critical state are suggested. Initial pulse frequency of pulsed start-up channel and power of neutron source are decreased by reduced rate of changing reactivity during automatic start-up, disposition of pulsed neutron detector in the range with neutron flux density to 5·10 12 s -1 cm -2 at standard power, separate signal of period for the use in chains of automatic start-up and emergency protection, reduction of pulses frequency of the start-up channel (the frequency is equal to 4000 c -1 ). Procedure and equations for the determination of optimal parameters are effected with the account of statistic character of pulsed detector frequency and false outlet signal [ru

  6. Does debt ceiling and government shutdown help in forecasting the us equity risk premium?

    Directory of Open Access Journals (Sweden)

    Aye Goodness C.

    2016-01-01

    Full Text Available This article evaluates the predictability of the equity risk premium in the United States by comparing the individual and complementary predictive power of macroeconomic variables and technical indicators using a comprehensive set of 16 economic and 14 technical predictors over a monthly out-ofsample period of 1995:01 to 2012:12 and an in-sample period of 1986:01- 1994:12. In order to do so we consider, in addition to the set of variables used in Christopher J. Neely et al. (2013 and using a more recent dataset, the forecasting ability of two other important variables namely government shutdown and debt ceiling. Our results show that one of the newly added variables namely government shutdown provides statistically significant out-of-sample predictive power over the equity risk premium relative to the historical average. Most of the variables, including government shutdown, also show significant economic gains for a risk averse investor especially during recessions.

  7. Estudio de las Startups

    OpenAIRE

    Rodríguez Reina, Cristina

    2016-01-01

    Este trabajo trata de analizar las pautas a la hora de poner en marcha una startup. Se explica el método que hay que seguir (Lean Startup), se expone una breve biografía de su autor, se muestran las distintas fases por las que atraviesa, las formas de financiación, así como una serie de puntos que servirán de ayuda para adentrarse en este mundo tan novedoso y hasta entonces tan poco conocido, como es el de la startups. Dentro del ámbito de las startups, se explicará el tema ...

  8. Proceedings of workshop on reactor shutdown system

    International Nuclear Information System (INIS)

    1997-03-01

    India has gained considerable experience in design, development, construction and operation of research and power reactors during the last four decades. Reactor shutdown system (RSS) is the most important engineered safety system of any reactor. A lot of technological developments have taken place to improve the reactor shutdown systems, particularly with advancement in reliability analysis and instrumentation and control. If the reactor is not shutdown, the fuel may melt, releasing radioactivity and possibly reactivity addition as in the case of Fast Breeder Reactor (FBR). Apart from radiological safety consequences, large investment has to be written off. The function of the RSS is to stop fission chain reaction and prevent breach of fuel. The design of RSS is multidisciplinary. It requires reactor physics analysis, design of absorber rods, drive mechanisms, safety logic to order shutdown and instrumentation to detect unsafe conditions. High reliability is essential and this requires two independent shutdown systems. This book contains the proceedings of the workshop on reactor shutdown system and papers relevant to INIS are indexed separately

  9. Start-up test of Fukushima Daini Nuclear Power Station Unit No.3

    International Nuclear Information System (INIS)

    Inomata, Toshio; Umezu, Akira; Kajikawa, Makoto; Koibuchi, Hiroshi; Netsu, Nobuhiko.

    1986-01-01

    In Unit 3 of the Fukushima Nuclear Power Station II (daini), a BWR power plant of output 1,100 MW, commercial operation was started in June 1985. Its start-up test was finished successfully in about nine months. That is, new equipments introduced were demonstration tested. Though the items of testing are increased, the start-up test took short time, resulting in construction period only 54.7 months of the Unit 3, the shortest in the world. During the test, there was no scramming other than the planned. Described are the following: an outline of the Unit 3, the items of its improvement and standardization, including the new equipments, preparations for the start-up test, the start-up test and its evaluation. (Mori, K.)

  10. Simulation of Darlington shutdown and regulation systems

    International Nuclear Information System (INIS)

    1986-10-01

    This report describes the development of a simulation of the Darlington Nuclear Generating Station shutdown and regulating systems, DARSIM. The DARSIM program simulates the spatial neutron dynamics, the regulation of the reactor power, and Shutdown System 1, SDS1, and Shutdown System 2, SDS2, software. The DARSIM program operates in the interactive simulation (INSIM) program environment

  11. Start-up strategies for thermophilic anaerobic digestion of pig manure

    International Nuclear Information System (INIS)

    Moset, V.; Bertolini, E.; Cerisuelo, A.; Cambra, M.; Olmos, A.; Cambra-López, M.

    2014-01-01

    Sludge physicochemical composition, methane (CH 4 ) yield, and methanogenic community structure and dynamics using quantitative real-time polymerase chain reaction were determined after start-up of anaerobic digestion of pig manure. Eight thermophilic continuous stirred anaerobic digesters were used during 126 days. Four management strategies were investigated: a feedless and a non-feedless period followed by a gradual or an abrupt addition of pig manure (two digesters per strategy). During the first 43 days, VFA (volatile fatty acids) accumulations and low CH 4 yield were observed in all digesters. After this period, digesters recovered their initial status being propionic acid the last parameter to be re-established. Non-feedless digesters with an abrupt addition of pig manure showed the best performances (lower VFA accumulation and higher CH 4 yield). Differences in microbial orders and dynamics, however, were less evident among treatments. Hydrogenotrophic methanogenesis, Methanomicrobiales first and Methanobacteriales second, was the dominant metabolic pathway in all digesters. Further research is needed to clarify the role and activity of hydrogenotrophic methanogens during the recovery start-up period and to identify the best molecular tools and methodologies to monitor microbial populations and dynamics reliably and accurately in anaerobic digesters. - Highlights: • Four start-up strategies for thermophilic anaerobic digestion of pig manure were tested. • Physicochemical composition, methane yield and methanogenic community were determined. • During the first 43 days, a decline in reactor's performance occurred. • The best start-up strategy was non-feedless with an abrupt addition of pig slurry. • Hydrogenotrophic methanogenesis was the dominant metabolic pathway

  12. 77 FR 65119 - Approval and Promulgation of Implementation Plans; Texas; Revisions to the New Source Review (NSR...

    Science.gov (United States)

    2012-10-25

    ...), Continuous Parameter Monitoring System (CPMS), and Predictive Emissions Monitoring System (PEMS). [cir... record (and in some cases report) emissions events, which include unscheduled maintenance, startup, and... shutdown activities'' with ``emissions from planned maintenance, startup, or shutdown activities,'' which...

  13. Identification of passive shutdown system parameters in a metal fueled LMR

    International Nuclear Information System (INIS)

    Vilim, R.B.

    1992-01-01

    This document discusses periodic testing of the passive shutdown system in a metal fueled liquid metal reactor which has been proposed as a Technical Specification requirement. In the approach to testing considered in this paper, perturbation experiments performed at normal operation are used to predict an envelope that bounds reactor response to flowrate, inlet temperature and external reactivity forcing functions. When the envelope for specific upsets lies within safety limits, one concludes that the passive shutdown system is operation properly for those upsets. Simulation results for the EBR-II reactor show that the response envelope for loss of flow and rod reactivity insertion events does indeed bound these events

  14. MODEL OF IT-STARTUPS MANAGEMENT

    OpenAIRE

    КОЗИНА, Ольга Андреевна; СТРАТИЕНКО, Наталия Константиновна

    2017-01-01

    Decrease mortality of startups during first three years of existing is an important task of the economy of any country. It has been established that the existing methods of enterprise management have some disadvantages or limits for using in IT-startups management. Analysis of mortality reasons of startups in different stages of their life cycle has been carried out. The comparing of reasons why startups in different time intervals, in different areas of them functioning are failure showed th...

  15. Safety shutdown separators

    Science.gov (United States)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

    2015-06-30

    The present invention pertains to electrochemical cells which comprise (a) an anode; (b) a cathode; (c) a solid porous separator, such as a polyolefin, xerogel, or inorganic oxide separator; and (d) a nonaqueous electrolyte, wherein the separator comprises a porous membrane having a microporous coating comprising polymer particles which have not coalesced to form a continuous film. This microporous coating on the separator acts as a safety shutdown layer that rapidly increases the internal resistivity and shuts the cell down upon heating to an elevated temperature, such as 110.degree. C. Also provided are methods for increasing the safety of an electrochemical cell by utilizing such separators with a safety shutdown layer.

  16. Influence of the feeding regime on the start-up and operation of the ...

    African Journals Online (AJOL)

    It was revealed that the feeding regime is an important factor in the successful start-up of the Anammox process. Nitrite concentration peaks at the beginning of a feeding period will lead to an unsuccessful start-up, while a slow input of nitrogen speeds up the process. Feeding regimes are less important in partial nitritation ...

  17. ORNL Isotopes Facilities Shutdown Program Plan

    International Nuclear Information System (INIS)

    Gibson, S.M.; Patton, B.D.; Sears, M.B.

    1990-10-01

    This plan presents the results of a technical and economic assessment for shutdown of the Oak Ridge National Laboratory (ORNL) isotopes production and distribution facilities. On December 11, 1989, the Department of Energy (DOE), Headquarters, in a memorandum addressed to DOE Oak Ridge Operations Office (DOE-ORO), gave instructions to prepare the ORNL isotopes production and distribution facilities, with the exception of immediate facility needs for krypton-85, tritium, and yttrium-90, for safe shutdown. In response to the memorandum, ORNL identified 17 facilities for shutdown. Each of these facilities is located within the ORNL complex with the exception of Building 9204-3, which is located at the Y-12 Weapons Production Plant. These facilities have been used extensively for the production of radioactive materials by the DOE Isotopes Program. They currently house a large inventory of radioactive materials. Over the years, these aging facilities have inherited the problems associated with storing and processing highly radioactive materials (i.e., facilities' materials degradation and contamination). During FY 1990, ORNL is addressing the requirements for placing these facilities into safe shutdown while maintaining the facilities under the existing maintenance and surveillance plan. The day-to-day operations associated with the surveillance and maintenance of a facility include building checks to ensure that building parameters are meeting the required operational safety requirements, performance of contamination control measures, and preventative maintenance on the facility and facility equipment. Shutdown implementation will begin in FY 1993, and shutdown completion will occur by the end of FY 1994

  18. Design philosophy of PFBR shutdown systems

    International Nuclear Information System (INIS)

    Rajan Babu, V.; Vijayashree, R.; Govindarajan, S.; Vaidyanathan, G.; Muralikrishna, G.; Shanmugam, T.K.; Chetal, S.C.; Raghavan, K.; Bhoje, S.B.

    1996-01-01

    This paper presents the overall design philosophy of shutdown system of 500 MWe Prototype Fast Breeder Reactor (PFBR). It discusses design criteria, parameters calling for safety action, different safety actions and the concepts conceived for shutdown systems. In tune with the philosophy of defence-in-depth, additional passive shutdown features, viz., Self Actuating Device (SADE) and Curie Point Magnetic (CPM) switch and protective feature like absorber rod Stroke Limiting Device (SLD) are contemplated. It also discusses about suitability of Gas Expansion Module (GEM) as one of the safety devices in PFBR. (author). 3 refs, 3 figs, 1 tab

  19. Recent operating experience during startup testing at latest 1100 MWe BWR-5 nuclear power plants

    International Nuclear Information System (INIS)

    Tanabe, Akira; Tateishi, Mizuo; Kajikawa, Makoto; Hayase, Yuichi.

    1986-01-01

    In June and September 1985, the latest two 1100 Mwe BWR-5 nuclear power plants started commercial operation about ten days earlier than initially expected without any unscheduled shutdown. These latest plants, 2F-3 and K-1, are characterized by an improved core with new 8 x 8 fuel assemblies, highly reliable control systems, advanced control room system and turbine steam full bypass system for full load rejection (2F3). This paper describes the following operating experiences gained during their startup testing. 1) Continuous operation at full load rejection. 2) Stable operation at natural circulating flow condition. 3) 31 and 23 hour short time start up operation. 4) 100-75-100 %, 1-8-1-14 hours daily load following operation. (author)

  20. Action plan during reactor shutdown in October 1965, Annex 5; Prilog br. 5 - Plan radova u toku stajanja reaktora u mesecu oktobru 1965. godine

    Energy Technology Data Exchange (ETDEWEB)

    Nikolic, M [Reaktor RA, Odelenje odrzavanja, Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

    1965-12-15

    The action plan of the division for reactor maintenance during reactor shutdown includes detailed list of tasks for mechanics, electronic and electrical equipment group during the reactor shutdown period in October 1965. It contains tasks for planned shutdown periods in September, August, July, May, April, March, and February 1965. [Serbo-Croat] Plan radova Odelenja odrzavanja reaktora RA za period stajanja reaktora u oktobru mesecu 1965. sadrzi detaljnu listu zadataka masinske grupe, elektro grupe i elektronske grupe. Ovaj prilog sadrzi i zadatke koji ce biti obavljeni tokom planiranih perioda kada je reaktor zaustavljen u septembru, avgustu, julu, junu, maju, aprilu, martu i februaru 1965.

  1. Acetate enhances startup of a H₂-producing microbial biocathode.

    Science.gov (United States)

    Jeremiasse, Adriaan W; Hamelers, Hubertus V M; Croese, Elsemiek; Buisman, Cees J N

    2012-03-01

    H(2) can be produced from organic matter with a microbial electrolysis cell (MEC). To decrease MEC capital costs, a cathode is needed that is made of low-cost material and produces H(2) at high rate. A microbial biocathode is a low-cost candidate, but suffers from a long startup and a low H(2) production rate. In this study, the effects of cathode potential and carbon source on microbial biocathode startup were investigated. Application of a more negative cathode potential did not decrease the startup time of the biocathode. If acetate instead of bicarbonate was used as carbon source, the biocathode started up more than two times faster. The faster startup was likely caused by a higher biomass yield for acetate than for bicarbonate, which was supported by thermodynamic calculations. To increase the H(2) production rate, a flow through biocathode fed with acetate was investigated. This biocathode produced 2.2 m(3) H(2) m(-3)  reactor day(-1) at a cathode potential of -0.7 V versus NHE, which was seven times that of a parallel flow biocathode of a previous study. Copyright © 2011 Wiley Periodicals, Inc.

  2. The use of digital computers in CANDU shutdown systems

    International Nuclear Information System (INIS)

    Gilbert, R.S.; Komorowski, C.W.

    1986-01-01

    This paper summarizes the application of computers in CANDU shutdown systems. A general description of systems that are already in service is presented along with a description of a fully computerized shutdown system which is scheduled to enter service in 1987. In reviewing the use of computers in the shutdown systems there are three functional areas where computers have been or are being applied. These are (i) shutdown system monitoring, (ii) parameter display and testing and (iii) shutdown initiation. In recent years various factors (References 1 and 2) have influenced the development and deployment of systems which have addressed two of these functions. At the present time a system is also being designed which addresses all of these areas in a comprehensive manner. This fully computerized shutdown system reflects the previous design, and licensing experience which was gained in earlier applications. Prior to describing the specific systems which have been designed a short summary of CANDU shutdown system characteristics is presented

  3. Strategies for the startup of methanogenic inverse fluidized-bed reactors using colonized particles.

    Science.gov (United States)

    Alvarado-Lassman, A; Sandoval-Ramos, A; Flores-Altamirano, M G; Vallejo-Cantú, N A; Méndez-Contreras, J M

    2010-05-01

    One of the inconveniences in the startup of methanogenic inverse fluidized-bed reactors (IFBRs) is the long period required for biofilm formation and stabilization of the system. Previous researchers have preferred to start up in batch mode to shorten stabilization times. Much less work has been done with continuous-mode startup for the IFBR configuration of reactors. In this study, we prepared two IFBRs with similar characteristics to compare startup times for batch- and continuous-operation modes. The reactors were inoculated with a small quantity of colonized particles and run for a period of 3 months, to establish the optimal startup strategy using synthetic media as a substrate (glucose as a source of carbon). After the startup stage, the continuous- and batch-mode reactors removed more than 80% of the chemical oxygen demand (COD) in 51 and 60 days of operation, respectively; however, at the end of the experiments, the continuous-mode reactor had more biomass attached to the support media than the batch-mode reactor. Both reactors developed fully covered support media, but only the continuous-mode reactor had methane yields close to the theoretical value that is typical of stable reactors. Then, a combined startup strategy was proposed, with industrial wastewater as the substrate, using a sequence of batch cycles followed by continuous operation, which allows stable operation at an organic loading rate of 20 g COD/L x d in 15 days. Using a fraction of colonized support as an inoculum presents advantages, with respect to previously reported strategies.

  4. Elementary calculation of the shutdown delay of a pile; Calcul elementaire de la periode d'extinction d'une pile

    Energy Technology Data Exchange (ETDEWEB)

    Yvon, J

    1949-04-01

    This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)

  5. Impact of reactor configuration on anammox process start-up: MBR versus SBR.

    Science.gov (United States)

    Tao, Yu; Gao, Da-Wen; Fu, Yuan; Wu, Wei-Min; Ren, Nan-Qi

    2012-01-01

    Anaerobic ammonium oxidation (anammox) is an energy saving biological nitrogen removal process which was limited to slow growth rate of anammox bacteria during start-up period. This study investigated the start-up of anammox process by a laboratory sequential batch reactor (SBR) for 218 days and subsequently modified the reactor as a membrane bioreactor (MBR) for 178 days. Modification of a SBR as MBR with installation of an external membrane module resulted in acceleration of specific anammox activity by 19 times. The acceleration of specific anammox activity with MBR was further confirmed by starting-up another MBR for a 242 day period. Molecular microbial analyses showed that Candidatus "Brocadia anammoxidans" and Candidatus "Kuenenia stuttgartiensis" were the dominant species in the inocula and biomass developed in the reactor. The start-up with MBR appeared to be more effective than SBR for the enrichment of anammox bacteria due to high sludge retention property of MBR configuration. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Reliability analysis of shutdown system

    International Nuclear Information System (INIS)

    Kumar, C. Senthil; John Arul, A.; Pal Singh, Om; Suryaprakasa Rao, K.

    2005-01-01

    This paper presents the results of reliability analysis of Shutdown System (SDS) of Indian Prototype Fast Breeder Reactor. Reliability analysis carried out using Fault Tree Analysis predicts a value of 3.5 x 10 -8 /de for failure of shutdown function in case of global faults and 4.4 x 10 -8 /de for local faults. Based on 20 de/y, the frequency of shutdown function failure is 0.7 x 10 -6 /ry, which meets the reliability target, set by the Indian Atomic Energy Regulatory Board. The reliability is limited by Common Cause Failure (CCF) of actuation part of SDS and to a lesser extent CCF of electronic components. The failure frequency of individual systems is -3 /ry, which also meets the safety criteria. Uncertainty analysis indicates a maximum error factor of 5 for the top event unavailability

  7. Startup activities of established Finnish companies

    OpenAIRE

    Saalasti, Sini

    2016-01-01

    Established companies have collaborated with startups for decades in order to enhance their capabilities in technology and innovation. However, in the recent years, the changes in the business environment have induced established companies to increase their collaboration with startups. Thus, startup activities of established companies have become a timely phenomenon. This study explores the startup activities of established companies by analyzing all the activity established companies conduct...

  8. Francis-99: Transient CFD simulation of load changes and turbine shutdown in a model sized high-head Francis turbine

    International Nuclear Information System (INIS)

    Mössinger, Peter; Jester-Zürker, Roland; Jung, Alexander

    2017-01-01

    With increasing requirements for hydropower plant operation due to intermittent renewable energy sources like wind and solar, numerical simulations of transient operations in hydraulic turbo machines become more important. As a continuation of the work performed for the first workshop which covered three steady operating conditions, in the present paper load changes and a shutdown procedure are investigated. The findings of previous studies are used to create a 360° model and compare measurements with simulation results for the operating points part load, high load and best efficiency. A mesh motion procedure is introduced, allowing to represent moving guide vanes for load changes from best efficiency to part load and high load. Additionally an automated re-mesh procedure is added for turbine shutdown to ensure reliable mesh quality during guide vane closing. All three transient operations are compared to PIV velocity measurements in the draft tube and pressure signals in the vaneless space. Simulation results of axial velocity distributions for all three steady operation points, during both load changes and for the shutdown correlated well with the measurement. An offset at vaneless space pressure is found to be a result of guide vane corrections for the simulation to ensure similar velocity fields. Short-time Fourier transformation indicating increasing amplitudes and frequencies at speed-no load conditions. Further studies will discuss the already measured start-up procedure and investigate the necessity to consider the hydraulic system dynamics upstream of the turbine by means of a 1D3D coupling between the 3D flow field and a 1D system model. (paper)

  9. Francis-99: Transient CFD simulation of load changes and turbine shutdown in a model sized high-head Francis turbine

    Science.gov (United States)

    Mössinger, Peter; Jester-Zürker, Roland; Jung, Alexander

    2017-01-01

    With increasing requirements for hydropower plant operation due to intermittent renewable energy sources like wind and solar, numerical simulations of transient operations in hydraulic turbo machines become more important. As a continuation of the work performed for the first workshop which covered three steady operating conditions, in the present paper load changes and a shutdown procedure are investigated. The findings of previous studies are used to create a 360° model and compare measurements with simulation results for the operating points part load, high load and best efficiency. A mesh motion procedure is introduced, allowing to represent moving guide vanes for load changes from best efficiency to part load and high load. Additionally an automated re-mesh procedure is added for turbine shutdown to ensure reliable mesh quality during guide vane closing. All three transient operations are compared to PIV velocity measurements in the draft tube and pressure signals in the vaneless space. Simulation results of axial velocity distributions for all three steady operation points, during both load changes and for the shutdown correlated well with the measurement. An offset at vaneless space pressure is found to be a result of guide vane corrections for the simulation to ensure similar velocity fields. Short-time Fourier transformation indicating increasing amplitudes and frequencies at speed-no load conditions. Further studies will discuss the already measured start-up procedure and investigate the necessity to consider the hydraulic system dynamics upstream of the turbine by means of a 1D3D coupling between the 3D flow field and a 1D system model.

  10. Sensitivity of BWR shutdown margin tests to local reactivity anomalies

    International Nuclear Information System (INIS)

    Cokinos, D.M.; Carew, J.F.

    1987-01-01

    Successful shutdown margin (SDM) demonstration is a required procedure in the startup of a newly configured boiling water reactor (BWR) core. In its most reactive condition throughout a cycle, a BWR core must be capable of being made subcritical by a specified margin with the highest worth control rod fully withdrawn and all other rods at their fully inserted positions. Two different methods are used to demonstrate SDM: (a) the adjacent-rod test and (b) the in-sequence test. In the adjacent-rod test, the strongest rod is fully withdrawn and an adjacent rod is withdrawn to reach criticality. In the in-sequence test, control rods spread throughout the core are withdrawn in a predetermined sequence of withdrawals. Larger than expected core k/sub eff/ values have been observed during the performance of BWR SDM tests. The purpose of the work summarized in this paper has been to investigated and quantify the sensitivity of both the adjacent-rod and in-sequence SDM tests to local reactivity anomalies. This was accomplished by introducing reactivity perturbations at selected four-bundle cell locations and by evaluating their effect on core reactivity in each of the two tests

  11. Maintenance, repair and operation (MRO) of shutdown facilities

    International Nuclear Information System (INIS)

    Kenny, S.

    2006-01-01

    What level of maintenance does one apply to a shutdown facility? Well it depends on who you ask. Operations staff sees facilities that have completed their useful life cycle as a cost drain while Decommissioning staff sees this as the start of a new life cycle. Based on the decommissioning plan for the particular facility the building could complete another full life cycle while under decommissioning whether it is in storage with surveillance mode or under active decommissioning. This paper will explore how you maintain a facility and systems for many years after its useful life until final decommissioning is completed. When a building is declared redundant, who looks after it until the final decommissioning end state is achieved? At the AECL, Chalk River Labs site the safe shutdown and turnover process is one key element that initiates the decommissioning process. The real trick is orchestrating maintenance, repair and operation plans for a facility that has been poorly invested in during its last years of useful life cycle. To add to that usually shutdowns are prolonged for many years beyond the expected turnover period. During this presentation I will cover what AECL is doing to ensure that the facilities are maintained in a proper state until final decommissioning can be completed. All facilities or systems travel through the same life cycle, design, construction, commissioning, operation, shutdown and demolition. As we all know, nuclear facilities add one more interesting twist to this life cycle called Decommissioning that lands between shutdown and demolition. As a facility nears the shutdown phase, operations staff loose interest in the facility and stop investing in upgrades, repairs and maintenance but continue to invest and focus on maximizing operations. Facility maintenance standards produced by the International Facility Maintenance Association (IFMA) based on a survey done every year state that 2.2% of the total operating costs for the site should be

  12. Failure of PWR-RHRS under cold shutdown conditions: Experimental results from the PKL test facility

    International Nuclear Information System (INIS)

    Mandl, R.M.; Umminger, K.J.; Logt, J.V.D.

    1991-01-01

    The Residual Heat Removal System (RHRS) of a PWR is designed to transfer thermal energy from the core after plant shutdown and maintain the plant in cold shutdown or refuelling conditions for extended periods of time. Initial reactor cooling after shutdown is achieved by dissipating heat through the steam generators (SGs) and discharging steam to the condenser by means of the Turbine Bypass System (TBS). When the reactor coolant temperature has dropped to about 160C and pressure has been reduced to 30 bar the RHRS is placed into operation. it reduces the coolant temperature to 50C within 20 hours after shutdown. The time margin for establishing alternate methods of heat removal following a failure of the RHRS depends on the Reactor Coolant System (RCS) temperature, the decay heat rate and the amount of RCS inventory. During some shutdown operations the RCS may be partially drained (e. g. to perform SG inspections). Decreased primary system inventory can significantly reduce the time available to recover the RHRS's function prior to bulk boiling and possible core uncovery. In the PKL test facility, which simulates a 1,300 MWe 4-loop PWR on a scale 1:145, a failure of RHRS under cold shutdown conditions was performed. This presentation gives a brief description of the test facility followed by the test objectives and results of this experiment

  13. Plasma shutdown device

    International Nuclear Information System (INIS)

    Hosogane, Nobuyuki; Nakayama, Takahide.

    1985-01-01

    Purpose: To prevent concentration of plasma currents to the plasma center upon plasma shutdown in a torus type thermonuclear device by the injection of fuels to the plasma center thereby prevent plasma disruption at the plasma center. Constitution: The plasma shutdown device comprises a plasma current measuring device that measures the current distribution of plasmas confined within a vacuum vessel and outputs a control signal for cooling the plasma center when the plasma currents concentrate to the plasma center and a fuel supply device that supplies fuels to the plasma center for cooling the center. The fuels are injected in the form of pellets into the plasmas. The direction and the velocity of the injection are set such that the pellets are ionized at the center of the plasmas. (Horiuchi, T.)

  14. II-1 General regulatory guide for staff on duty; II-1 Opsti pravilnik za rad dezurnog osoblja

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1960-07-01

    Personnel responsible for RA reactor operation is working in shifts. This regulatory guide describes in detail rights, tasks and responsibilities of each staff member in duty when operating the reactor under regular conditions, during start-up, during shutdown, during repair and maintenance shutdown periods. Rad reaktora odvija se po smenama. Ovaj pravilnik regulise prava, duznosti i odgovornost svakog od clanova tima u smeni pojedinacno u regularnim uslovima rada, prilikom remonta, u toku stajanja, dostizanja nominalne snage, zaustavljanja rada reaktora.

  15. 77 FR 4522 - National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources

    Science.gov (United States)

    2012-01-30

    ... During Periods of Startup, Shutdown and Malfunctions (SSM) VI. Requirements for Metal HAP Process Vents A. Definition of Metal HAP Process Vent B. Metal HAP Process Vent Standards VII. Technical Corrections and...: Chromium Compounds, Polyvinyl Chloride and Copolymers Production, Paint and Allied Coatings and Mercury...

  16. Preliminary considerations on the startup phase for the ASTRID core

    International Nuclear Information System (INIS)

    Mignot, G.

    2015-01-01

    This paper presents preliminary considerations on the startup phase for the ASTRID core, as well as an overview of the different steps before reaching the optimised equilibrium core. The start-up phase is assumed to cover the period between loading the dummy core into the reactor (for commissioning tests) and achieving the optimised equilibrium core. Four main stages are considered: a first stage of start-up tests before fuel core loading, a second stage related to zero power and power ramp-up tests, a third stage corresponding to the transition from the first core to the equilibrium contractual core, and the last stage to reach the optimised performance for the equilibrium core. In the two last stages, a sub-assembly surveillance plan based on post-irradiation examinations is taken into account. As this work is in its preliminary stages, the first scenarios shown for the start-up phase must not be considered as the ASTRID reference scenarios. The scenarios strongly depend on the assumptions considered in the analysis, whereas those discussed in this paper aim at outlining the content and the duration of the starting phases for the ASTRID core, which will be useful in subsequently assessing the core sub-assembly fabrication needs. Assumptions for the start-up phase will be updated in accordance with progress on the ASTRID core design development and core qualification programme. (author)

  17. Reactor shutdown system of prototype fast breeder reactor

    International Nuclear Information System (INIS)

    Govindarajan, S.; Singh, Om Pal; Kasinathan, N.; Paramasivan Pillai, C.; Arul, A.J.; Chetal, S.C.

    2002-01-01

    Full text: The shutdown system of PFBR is designed to assure a very high reliability by employing well known principles of redundancy, diversity and independence. The failure probability of the shutdown system limited to -6 / ry. Salient features of the shutdown system are: Two independent shutdown systems, each of them able to accommodate an additional single failure and made up of a trip system and an associated absorber rod group. Diversity between trip systems, rods and mechanisms. Initiation of SCRAM by two diverse physical parameters of the two shutdown systems for design events leading potentially to unacceptable conditions is the core. The first group of nine rods called control and safety rods (CSR) is used for both shutdown as well as power regulation. The second group consisting of three rods known as diverse safety rods (DSR) is used only for shutdown. Diversity between the two groups is ensured by varying the operating conditions of the electromagnets and the configurations of the mobile parts. The reactivity worth of the absorber rods have been chosen such that each group of rods would ensure cold shutdown on SCRAM even when the most reactive rod of the group fails to drop. Together the two groups ensure a shutdown margin of 5000 pcm. The speed and individual rod worth of the CSR is chosen from operational and safety considerations during reactor start up and raising of power. Required drop time of rods during SCRAM depends on the incident considered. For a severe reactivity incident of 3 $/s this has to be limited to 1s and is ensured by limiting electromagnet response time and facilitating drop by gravity. Design safety limits for core components have been determined and SCRAM parameters have been identified by plant dynamic analysis to restrict the temperatures of core components within the limits. The SCRAM parameters are distributed between the two systems appropriately. Fault tree analysis of the system has been carried out to determine the

  18. Light duty utility arm startup plan

    International Nuclear Information System (INIS)

    Barnes, G.A.

    1998-01-01

    This Startup Plan encompasses activities necessary to perform startup and operation of the LDUA in Facility Group 3 tanks and complete turnover to CPO. The activities discussed in this plan will occur prior to, and following the US Department Energy, Richland Operations Office Operational Readiness Review. This startup plan does not authorize or direct any specific field activities or authorize a change of configuration. As such, this startup plan need not be Unresolved Safety Question (USQ) screened

  19. Is there a lean future for global startups?

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2017-01-01

    This article integrates insights from the latest research on the lean startup entrepreneurial method, born-global firms, and global startups. It contributes to the clarification of terminology referring to the global aspects of startups, summarizes insights from previous literature focusing on gl......-based global startup research and practice. The analysis should benefit both researchers and practitioners in technology entrepreneurship, international entrepreneurship, and global innovation management.......This article integrates insights from the latest research on the lean startup entrepreneurial method, born-global firms, and global startups. It contributes to the clarification of terminology referring to the global aspects of startups, summarizes insights from previous literature focusing...... on global startups, and further substantiates the articulation of the need for considering the lean global startup as a new type of firm. The main message is that the lessons learned from the emergence of lean startup entrepreneurship offer a basis for promoting a similar lean phase in technology...

  20. Influence of temperature histories during reactor startup periods on microstructural evolution and mechanical properties of austenitic stainless steel irradiated with neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kasahara, Shigeki, E-mail: kasahara.shigeki@jaea.go.jp [Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Kitsunai, Yuji [Nippon Nuclear Fuel Development, 2163 Narita-cho, Oarai-machi, Higashi-ibaraki-gun, Ibaraki 311-1313 (Japan); Chimi, Yasuhiro [Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Chatani, Kazuhiro; Koshiishi, Masato [Nippon Nuclear Fuel Development, 2163 Narita-cho, Oarai-machi, Higashi-ibaraki-gun, Ibaraki 311-1313 (Japan); Nishiyama, Yutaka [Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

    2016-11-15

    This paper addresses influence of two different temperature profiles during startup periods in the Japan Materials Testing Reactor and a boiling water reactor upon microstructural evolution and mechanical properties of austenitic stainless steel irradiated with neutrons to about 1 dpa and 3 dpa. One of the temperature profiles was that the specimens experienced neutron irradiation in both reactors, under which the irradiation temperature transiently increased to 290 °C from room temperature with increasing reactor power during reactor startup periods. Another was that the specimens were pre-heated to about 150 °C prior to the irradiation to suppress the transient temperature increase. Tensile tests at 290 °C and Vickers hardness tests at room temperature were carried out, and their microstructures were observed by FEG-TEM. Difference of the temperature profiles was observed obviously in interstitial cluster formation, in particular, growth of Frank loops. Although influence of neutron irradiation involving transient temperature increase to 290 °C from room temperature on the yield strength and the Vickers hardness is buried in the trend curves of existing data, the influence was also found certainly in increment of in yield strength, existence of modest yield drop, and loss of strain hardening capacity and ductility. As a result, Frank loops, which were observed in austenitic stainless steel irradiated at doses of 1 dpa or more, seemed to have important implications regarding the interpretation of not irradiation hardening, but deformation of the austenitic stainless steel.

  1. LMFBR self-activated shutdown systems

    International Nuclear Information System (INIS)

    Sowa, E.S.; Barthold, W.P.; Eggen, D.T.; Huebotter, P.R.; Josephson, J.; Pizzica, P.A.; Turski, R.B.; van Erp, J.B.

    1976-01-01

    Self-actuated shutdown systems (SASSs), fully contained within the dimensions of a fuel subassembly and installed in the core in judiciously chosen locations, can provide an important additional safety feature for LMFBRs. If actuated by phenomena inherent to the system and its immediate environment, these systems can contribute considerably to the total reliability of the overall plant protection system, in particular as regards protection against human error. It was shown that this type of shutdown system is capable of inserting a substantial amount of negative reactivity into the core with a relatively small impact on plant performance. Furthermore, it was shown that a coolable geometry can be maintained in LMFBRs of current design for a wide spectrum of accident initiators, and for a range of response times and insertion rates which appear to be achievable within practical design limits. Experiments showed that Curie-point-operated devices have considerable promise for application in self-actuated shutdown systems, in particular as regards meeting the requirements of testability and resettability

  2. The role of relationships in start-up development

    DEFF Research Database (Denmark)

    Mattsson, Jan; Helmersson, Helge; Standing, Craig

    2017-01-01

    Relationships are important in the business start-up phase for a variety of reasons. Internal relationships can support knowledge exchange that determines the business model development and external relationships can facilitate a wide range of opportunities, support and insights. The paper explains...... the key relationships experienced by the founding team of a recently formed Swedish digital trading platform. Data were gathered through a self-reporting diary approach based on the Critical Incident Technique format and texts were analysed by the Pertex text-analytic software. The findings explain how...... important relationships were formed during the initial start-up period targeting international expansion. Interaction with early adopters enabled a rapid evolution of the business platform with the aim to build a community of users to support development....

  3. Start-up of anaerobic digestion of source-sorted organic municipal solid waste

    International Nuclear Information System (INIS)

    Maroun, Rania

    2004-01-01

    Municipal solid waste (MSW) disposal is a major environmental concern worldwide. Among the environmentally sound technologies for the treatment of MSW, composting in the form of anaerobic digestion (AD) appears as a suitable alternative that offers the advantage of rapid stabilization of organic matter, reduction in waste volume, production of methane, and minimal environmental impacts in comparison to land filling and incineration. Yet, although outstanding advances in anaerobic digestion of solid substrate have been made in the last 10 years, some development areas are lagging, including the fast and reliable process start-up in terms of type of inocula and overall start-up strategies. The present study investigates the start-up and operation of bench-scale anaerobic digesters treating the source-sorted organic fraction of municipal solid waste. The experimental program consisted of starting up two digesters in parallel. Three consecutive interventions in the start-up program were implemented to achieve steady state. Start-up was relatively slow indicating the seed obtained from an operating anaerobic wastewater treatment plant was not suitable. The use of cattle manure together with effluent dilution reduced the acclimation period (Author.)

  4. Fort St. Vrain Nuclear Generating Station. Semiannual operations report, January--June 1975

    International Nuclear Information System (INIS)

    1975-01-01

    The reactor was in start-up testing during this period. Information is presented concerning fuel and equipment performance; changes in facility design; procedures; testing; staff; licensed operator training; surveillance; power generation; maintenance; shutdowns, primary coolant chemistry; radiation exposure; fission product release; solid wastes; and radioactive effluents

  5. 40 CFR 63.1547 - Monitoring requirements.

    Science.gov (United States)

    2010-07-01

    ... paragraph (a) of this section. In no event shall the sensitivity be increased by more than 100 percent or... included in the calculation. (2) Alarms that occur during startup, shutdown, or malfunction shall not be included in the calculation if the condition is described in the startup, shutdown, and malfunction plan...

  6. SBWR core thermal hydraulic analysis during startup

    International Nuclear Information System (INIS)

    Lin, J.H.; Huang, R.L.; Sawyer, C.D.

    1993-01-01

    This paper reports on a thermal hydraulic analysis of the SIMPLIFIED BOILING WATER REACTOR (SBWR) during startup. The potential instability during a SBWR startup has drawn the attention of designers, researchers, and engineers. It has not been a concern for a Boiling Water Reactor (BWR) with forced recirculation; however, for SBWR with natural circulation the concern exists. The concern is about the possibility of a geysering mode oscillation during SBWR startup from a cold temperature and a low system pressure with a low natural circulation flow rate. A thermal hydraulic analysis of the SBWR is performed in simulation of the startup using the TRACG computer code. The temperature, pressure, and reactor power profiles of SBWR during the startup are presented. The results are compared with the data of a natural circulation boiling water reactor, the DODEWAARD plant, in which no instabilities have been observed during many startups. It is shown that a SBWR startup which follows proper procedures, geysering and other modes of oscillations can be avoided

  7. Lean start-up

    DEFF Research Database (Denmark)

    Rasmussen, Erik Stavnsager; Tanev, Stoyan

    2016-01-01

    The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The ma...... and the final business model. In other words: The start-up must first nail the problem together with the customers, then develop the solution and test, and then in the end scale it to a full-grown business model.......The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The main...

  8. Risks Associated with Shutdown in PWRs

    International Nuclear Information System (INIS)

    Grlicarev, I.

    1996-01-01

    The selected set of risks associated with reactor shutdown in PWRs are outlined and discussed (e. g. outage planning, residual heat removal capability, rapid boron dilution, containment integrity, fire protection). The contribution of different outage strategies to overall core damage risk during shutdown is assessed for a particular basic outage plan. The factors which increase or minimize the probability of reactor coolant boiling or core damage are analysed. (author)

  9. Is There a Lean Future for Global Startups?

    Directory of Open Access Journals (Sweden)

    Stoyan Tanev

    2017-05-01

    Full Text Available This article integrates insights from the latest research on the lean startup entrepreneurial method, born-global firms, and global startups. It contributes to the clarification of terminology referring to the global aspects of startups, summarizes insights from previous literature focusing on global startups, and further substantiates the articulation of the need for considering the lean global startup as a new type of firm. The main message is that the lessons learned from the emergence of lean startup entrepreneurship offer a basis for promoting a similar lean phase in technology-based global startup research and practice. The analysis should benefit both researchers and practitioners in technology entrepreneurship, international entrepreneurship, and global innovation management.

  10. 76 FR 54465 - Proposed Settlement Agreement, Clean Air Act Citizen Suit

    Science.gov (United States)

    2011-09-01

    ... (24) months after issuing a finding of failure to submit State Implementation Plans (``SIPs'') meeting...) at issue. No later than 15 business days following signature on each notice related to a proposed or... excess emissions from sources during periods of startup, shutdown, or malfunction (``SSM'') that may be...

  11. 40 CFR 63.8635 - What reports must I submit and when?

    Science.gov (United States)

    2010-07-01

    ...? 63.8635 Section 63.8635 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... reporting period into those that are due to startup, shutdown, control equipment problems, process problems... that is subject to the work practice standard specified in Table 3 to this subpart, and you use a fuel...

  12. Fusion reactor design studies

    International Nuclear Information System (INIS)

    Santarius, J.F.; Kulcinski, G.L.; Emmert, G.A.

    1991-01-01

    This progress report will give a detailed breakdown of the work accomplished for ARIES-III during the contract period, November 1, 1990 to October 31, 1991. The areas of effort discussed are: Neutronics; First-Wall; Shield; Safety; Systems; Startup and Shutdown; Energy Conversion; Ripple Loss; and Fuel Resources

  13. Start-up and stabilization of an Anammox process from a non-acclimatized sludge in CSTR.

    Science.gov (United States)

    Bagchi, Samik; Biswas, Rima; Nandy, Tapas

    2010-09-01

    Development of an Anammox (anaerobic ammonium oxidation) process using non-acclimatized sludge requires a long start-up period owing to the very slow growth rate of Anammox bacteria. This article addresses the issue of achieving a shorter start-up period for Anammox activity in a well-mixed continuously stirred tank reactor (CSTR) using non-acclimatized anaerobic sludge. Proper selection of enrichment conditions and low stirring speed of 30 +/- 5 rpm resulted in a shorter start-up period (82 days). Activity tests revealed the microbial community structure of Anammox micro-granules. Ammonia-oxidizing bacteria (AOB) were found on the surface and on the outer most layers of granules while nitrite-oxidizing bacteria (NOB) and Anammox bacteria were present inside. Fine-tuning of influent NO2(-)/NH4+ ratio allowed Anammox activity to be maintained when mixed microbial populations were present. The maximum nitrogen removal rate achieved in the system was 0.216 kg N/(m(3) day) with a maximum specific nitrogen removal rate of 0.434 g N/(g VSS day). During the study period, Anammox activity was not inhibited by pH changes and free ammonia toxicity.

  14. The physics of tokamak start-up

    International Nuclear Information System (INIS)

    Mueller, D.

    2013-01-01

    Tokamak start-up on present-day devices usually relies on inductively induced voltage from a central solenoid. In some cases, inductive startup is assisted with auxiliary power from electron cyclotron radio frequency heating. International Thermonuclear Experimental Reactor, the National Spherical Torus Experiment Upgrade and JT60, now under construction, will make use of the understanding gained from present-day devices to ensure successful start-up. Design of a spherical tokamak (ST) with DT capability for nuclear component testing would require an alternative to a central solenoid because the small central column in an ST has insufficient space to provide shielding for the insulators in the solenoid. Alternative start-up techniques such as induction using outer poloidal field coils, electron Bernstein wave start-up, coaxial helicity injection, and point source helicity injection have been used with success, but require demonstration of scaling to higher plasma current

  15. COMPUTING SERVICES DURING THE ANNUAL CERN SHUTDOWN

    CERN Multimedia

    2001-01-01

    As in previous years, computing services run by IT division will be left running unattended during the annual shutdown. The following points should be noted. No interruptions are scheduled for local and wide area networking and the ACB, e-mail and unix interactive services. Unix batch services will be available but without access to manually mounted tapes. Dedicated Engineering services, general purpose database services and the Helpdesk will be closed during this period. An operator service will be maintained and can be reached at extension 75011 or by Email to computer.operations@cern.ch. Users should be aware that, except where there are special arrangements, any major problems that develop during this period will most likely be resolved only after CERN has reopened. In particular, we cannot guarantee backups for Home Directory files (for Unix or Windows) or for email folders. Any changes that you make to your files during this period may be lost in the event of a disk failure. Please note that all t...

  16. DOES FAMILY SOCIAL SUPPORT AFFECT STARTUP BUSINESS ACTIVITIES?

    Directory of Open Access Journals (Sweden)

    Nurlaily F.

    2018-02-01

    Full Text Available In recent years, StartUp has shown a considerable progress in Indonesia. Although most of the StartUps are newly established companies in phase to find the right markets, the StartUps are expected to contribute to the economy and solve local problems. In Indonesia most of the StartUps are still in the idea stage. Therefore, they have no profit, loss, or even failure. It causes the StartUps to be difficult in gaining trust from investors. To overcome these problems, support from various parties is necessary for the development of StartUp activities. One of them is a support from family (Family Social Support. Previous studies have shown that family support contributes to the success of an entrepreneur. However, there has been no research on the relationship between family support with StartUp activities, especially in developing countries like Indonesia. This study examined the influence of family social support in the form of financial capital support, social capital, human capital, physical capital, and family cohesiveness on StartUp activities in Indonesia by using Poisson regression analysis. The results showed that family cohesiveness had a significant effect on the increase of StartUp activities.

  17. Startup methods for single-mode gyrotron operation

    International Nuclear Information System (INIS)

    Whaley, D.R.; Tran, M.Q.; Alberti, S.; Tran, T.M.; Antonsen, T.M. Jr.; Dubrovin, A.; Tran, C.

    1995-01-01

    Experimental results of startup studies on a 118 GHz TE 22,6 gyrotron are presented and compared with theory. The startup paths through the energy-velocity-pitch-angle plane are determined by the time evolution of the beam parameters during the startup phase. These startup paths are modified by changing the anode and cathode voltage rise from zero to their nominal values and are seen to determine the cavity oscillating mode. Experimental results show specifically that competition between the TE 22,6 and TE -19,7 mode can be completely eliminated by use of the proper startup method in a case where a typical triode startup results in oscillation in the competing TE -19,7 mode. These new results are shown to be in excellent agreement with the theory whose approach is general and therefore applicable to gyrotrons operating in any arbitrary cavity mode. (author) 3 figs., 4 refs

  18. Innovative Startup-Projects: Experience, Evaluation, Implementation Contradictions

    Directory of Open Access Journals (Sweden)

    Inshakov Maksim Olegovich

    2015-09-01

    Full Text Available Innovative companies in the conditions of global post-crisis economic recovery and increased economic activity become again a promising area for investments of large investment and venture capital funds, venture divisions of large transnational corporations, business angels and other private investors. This is confirmed by the data on the increase in the volume of venture capital market in the US and Europe and on a significant increase in the cost of the leading foreign and Russian start-up companies which are rated as of 2014 in the present article. The comparative analysis of the leading Russian and foreign start-ups showed the prevalence of companies engaged in the field of IT-Internet-Mobile and focused on the provision of various kinds of innovative services to consumers among the foreign participants of the rating. Among Russian startups-winners the companies of technological orientation (biological, medical, and “clean” technologies dominate. They reflect the increasing importance of start-ups in the innovative development of the Russian economy. Participation in such competitions and ratings is a favorable factor of promoting start-ups, increasing awareness of potential investors and consumers of start-up products. The importance of start-ups formation and the development of effective regional and national innovation systems update the studies related to the identification of the fundamental contradictions in the activities of Russian start-ups and to the development of recommendations for their resolution. The article identifies the key issues of economic, organizational, informational and marketing character causing the collapse of start-up projects in the Russian economy in modern conditions.

  19. The Upgrade of the CMS RPC System during the First LHC Long Shutdown

    CERN Document Server

    Tytgat, M.; Verwilligen, P.; Zaganidis, N.; Aleksandrov, A.; Genchev, V.; Iaydjiev, P.; Rodozov, M.; Shopova, M.; Sultanov, G.; Assran, Y.; Abbrescia, M.; Calabria, C.; Colaleo, A.; Iaselli, G.; Loddo, F.; Maggi, M.; Pugliese, G.; Benussi, L.; Bianco, S.; Caponero, M.; Colafranceschi, S.; Felli, F.; Piccolo, D.; Saviano, G.; Carrillo, C.; Berzano, U.; Gabusi, M.; Vitulo, P.; Kang, M.; Lee, K.S.; Park, S.K.; Shin, S.; Sharma, A.

    2012-01-01

    The CMS muon system includes in both the barrel and endcap region Resistive Plate Chambers (RPC). They mainly serve as trigger detectors and also improve the reconstruction of muon parameters. Over the years, the instantaneous luminosity of the Large Hadron Collider gradually increases. During the LHC Phase 1 (~first 10 years of operation) an ultimate luminosity is expected above its design value of 10^34/cm^2/s at 14 TeV. To prepare the machine and also the experiments for this, two long shutdown periods are scheduled for 2013-2014 and 2018-2019. The CMS Collaboration is planning several detector upgrades during these long shutdowns. In particular, the muon detection system should be able to maintain a low-pT threshold for an efficient Level-1 Muon Trigger at high particle rates. One of the measures to ensure this, is to extend the present RPC system with the addition of a 4th layer in both endcap regions. During the first long shutdown, these two new stations will be equipped in the region |eta|<1.6 with...

  20. Experience with after-shutdown decay heat removal - BWRs and PWRs

    International Nuclear Information System (INIS)

    Haugh, J.J.; Mollerus, F.J.; Booth, H.R.

    1992-01-01

    Boiling-water reactors (BWRs) and pressurized-water reactors (PWRs) make use of residual heat removal systems (RHRSs) during reactor shutdown. RHRS operational events involving an actual loss or significant degradation of an RHRS during shutdown heat removal are often prompted or aggravated by complex, changing plant conditions and by concurrent maintenance operations. Events involving loss of coolant inventory, loss of decay heat removal capability, or inadvertent pressurization while in cold shutdown have occurred. Because fewer automatic protective fetures are operative during cold shutdowns, both prevention and termination of events depend heavily on operator action. The preservation of RHRS cooling should be an important priority in all shutdown operations, particularly where there is substantial decay heat and a reduced water inventory. 13 refs., 3 figs., 4 tabs

  1. Preliminary Evaluation of Removing Used Nuclear Fuel From Nine Shutdown Sites

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, Steven J.; Best, Ralph; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul

    2013-04-30

    The Blue Ribbon Commission on America’s Nuclear Future identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses. In this report, a preliminary evaluation of removing used nuclear fuel from nine shutdown sites was conducted. The shutdown sites included Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion. At these sites a total of 7649 used nuclear fuel assemblies and a total of 2813.2 metric tons heavy metal (MTHM) of used nuclear fuel are contained in 248 storage canisters. In addition, 11 canisters containing greater-than-Class C (GTCC) low-level radioactive waste are stored at these sites. The evaluation was divided in four components: • characterization of the used nuclear fuel and GTCC low-level radioactive waste inventory at the shutdown sites • an evaluation of the onsite transportation conditions at the shutdown sites • an evaluation of the near-site transportation infrastructure and experience relevant to the shipping of transportation casks containing used nuclear fuel from the shutdown sites • an evaluation of the actions necessary to prepare for and remove used nuclear fuel and GTCC low-level radioactive waste from the shutdown sites. Using these evaluations the authors developed time sequences of activities and time durations for removing the used nuclear fuel and GTCC low-level radioactive waste from a single shutdown site, from three shutdown sites located close to each other, and from all nine shutdown sites.

  2. Startup methods for single-mode gyrotron operation

    International Nuclear Information System (INIS)

    Whaley, D.R.; Tran, M.Q.; Alberti, S.; Tran, T.M.; Antonsen, T.M.; Tran, C.

    1995-03-01

    Experimental results of startup studies on a 118 GHz TE 22,6 gyrotron are presented and compared with theory. The theoretical excitation regimes of competing modes are computed in the energy-velocity-pitch-angle plane near the operation point. The startup paths through the plane are determined by the time evolution of the beam parameters during the startup phase. These startup paths are modified by changing the anode and cathode voltage rise from zero to their nominal values and are seen to determine the cavity oscillating mode. Experimental results show specifically that competition between the TE 22,6 and TE -19,7 mode can be completely eliminated by using the proper startup method in a case where a typical triode startup results in oscillation in the competing TE -19,7 mode. These new results are shown to be in excellent agreement with theory whose approach is general and therefore applicable to gyrotrons operating in any arbitrary cavity mode. (author) 5 figs., 1 tab., 13 refs

  3. DOES FAMILY SOCIAL SUPPORT AFFECT STARTUP BUSINESS ACTIVITIES?

    OpenAIRE

    Nurlaily F.; Aini E.K.; Asmoro P.S.

    2018-01-01

    In recent years, StartUp has shown a considerable progress in Indonesia. Although most of the StartUps are newly established companies in phase to find the right markets, the StartUps are expected to contribute to the economy and solve local problems. In Indonesia most of the StartUps are still in the idea stage. Therefore, they have no profit, loss, or even failure. It causes the StartUps to be difficult in gaining trust from investors. To overcome these problems, support from various partie...

  4. Unit commitment solution using agglomerative and divisive cluster algorithm : an effective new methodology

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, N.M.; Reddy, K.R. [G. Narayanamma Inst. of Technology and Science, Hyderabad (India). Dept. of Electrical Engineering; Ramana, N.V. [JNTU College of Engineering, Jagityala (India). Dept. of Electrical Engineering

    2008-07-01

    Thermal power plants consist of several generating units with different generating capacities, fuel cost per MWH generated, minimum up/down times, and start-up or shut-down costs. The Unit Commitment (UC) problem in power systems involves determining the start-up and shut-down schedules of thermal generating units to meet forecasted load over a future short term for a period of one to seven days. This paper presented a new approach for the most complex UC problem using agglomerative and divisive hierarchical clustering. Euclidean costs, which are a measure of differences in fuel cost and start-up costs of any two units, were first calculated. Then, depending on the value of Euclidean costs, similar type of units were placed in a cluster. The proposed methodology has 2 individual algorithms. An agglomerative cluster algorithm is used while the load is increasing, and a divisive cluster algorithm is used when the load is decreasing. A search was conducted for an optimal solution for a minimal number of clusters and cluster data points. A standard ten-unit thermal unit power system was used to test and evaluate the performance of the method for a period of 24 hours. The new approach proved to be quite effective and satisfactory. 15 refs., 9 tabs., 5 figs.

  5. First LHC Shutdown: Coordination and Schedule Issues

    CERN Document Server

    Coupard, J; Grillot, S

    2010-01-01

    The first LHC shutdown started in fall 2008, just after the incident on the 19th of September 2008. In addition to the typical work of a shutdown, a large number of interventions, related to the “consolidation after the incident” were performed in the LHC loop. Moreover the amount of work increased during the shutdown, following the recommendations and conclusions of the different working groups in charge of the safety of the personnel and of the machine. This paper will give an overview of the work performed, the organization of the coordination, emphasizing the new safety risks (electrical and cryogenic), and how the interventions were implemented in order to ensure both the safety of personnel and a minimized time window.

  6. Evolution of shutdown mechanism for PHWRs

    International Nuclear Information System (INIS)

    Singh, Manjit; Govindarajan, G.

    1997-01-01

    In 500 MWe PHWR, there are two independent fast acting shutdown systems namely (1) mechanical shut-off rod system and (2) liquid poison injection system. Both systems are independently capable of keeping the reactor in sub-critical condition during long shutdown. Mechanical shut-off rod system being primary shutdown system calls for a very high reliability of operation as well as effectiveness, which are mainly governed by its ability to operate within a very short time and the magnitude of negative reactivity worth it can provide. Mechanical shut-off rods are normally parked above the core by shut-off rod drive mechanism. On receiving a scram signal, shut-off rods are released from the holding electromagnetic clutch and fall under gravity into the core. This paper discusses the salient features of mechanical shut-off rod system. A brief account of detailed design and development of sub-assemblies of shut-off rod drive mechanism is also presented. (author)

  7. A Fast Shutdown Technique for Large Tokamaks

    International Nuclear Information System (INIS)

    Fredrickson, E.; Schmidt, G.L.; Hill, K.; Jardin, S.C.

    1999-01-01

    A practical method is proposed for the fast shutdown of a large ignited tokamak. The method consists of injecting a rapid series of 30-50 deuterium pellets doped with a small ( 0.0005%) concentration of Krypton impurity, and simultaneously ramping the plasma current and shaping fields down over a period of several seconds using the poloidal field system. Detailed modeling with the Tokamak Simulation Code using a newly developed pellet mass deposition model shows that this method should terminate the discharge in a controlled and stable way without producing significant numbers of runaway electrons. A partial prototyping of this technique was accomplished in TFTR

  8. 40 CFR 61.09 - Notification of startup.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Notification of startup. 61.09 Section...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS General Provisions § 61.09 Notification of startup. (a) The owner or operator of each stationary source which has an initial startup after the effective...

  9. Development of pre-startup equipment for light water reactors

    International Nuclear Information System (INIS)

    Ram, Rajit; Borkar, S.P.; Dixit, M.Y.; Das, Debashis; Patil, R.K.

    2010-01-01

    Light water reactor (LWR) core typically has high excess reactivity as compared to Pressurized Heavy Water Reactor (PHWR). Unlike PHWR, where online refueling is done, LWR is operated for a long period to achieve maximum fuel burn-up before refueling. Since the reactivity is always reducing with burn-up of the core, the positions of control rods at criticality are always changing in a single direction, i.e. away from the core. Therefore it is possible to start the LWR even if the nuclear instrumentation is not online, provided the criticality position of control rods is known for previous operation. However, for the very first startup, the criticality position of control rods is required to be determined. A special nuclear instrumentation system, called Pre-startup equipment (PSE) is developed using two numbers of in-core detectors along with the processing electronics. The PSE enables operators to determine the criticality position of control rods for the first startup at zero power. The same equipment can also be used during loading of fuel assemblies. This paper discusses the features and architecture of PSE, its individual circuit blocks and specifications. (author)

  10. CANDU 6 liquid injection shutdown system waterhammer analysis using PTRAN

    International Nuclear Information System (INIS)

    Ko, Deuk Yoon; Kim, Eun Ki; Ko, Yong Sang; Park, Byung Ho; Kim, Seok Bum

    1996-06-01

    An in-core LOCA could result in flooding of the helium header in the liquid injection shutdown system. Flooding of the helium header will result in severe pressure transients (waterhammer) in the liquid injection shutdown system when the shutdown signal is initiated. To evaluate the impact of the dynamic effects of this event, a pressure transient analysis has been performed. This analysis is performed using PTRAN, which is a computer program based on the method of characteristics. The results of this analysis are used in the stress analysis of the piping and pipe supports to ensure that the liquid injection shutdown system can withstand the pressure transient loadings. This analysis report documents the results of waterhammer analysis performed for the liquid injection shutdown system for the Wolsung nuclear power plant unit 2, 3 and 4. 4 tabs., 11 figs., 15 refs. (Author)

  11. CANDU 6 liquid injection shutdown system waterhammer analysis using PTRAN

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Deuk Yoon; Kim, Eun Ki; Ko, Yong Sang; Park, Byung Ho; Kim, Seok Bum [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-06-01

    An in-core LOCA could result in flooding of the helium header in the liquid injection shutdown system. Flooding of the helium header will result in severe pressure transients (waterhammer) in the liquid injection shutdown system when the shutdown signal is initiated. To evaluate the impact of the dynamic effects of this event, a pressure transient analysis has been performed. This analysis is performed using PTRAN, which is a computer program based on the method of characteristics. The results of this analysis are used in the stress analysis of the piping and pipe supports to ensure that the liquid injection shutdown system can withstand the pressure transient loadings. This analysis report documents the results of waterhammer analysis performed for the liquid injection shutdown system for the Wolsung nuclear power plant unit 2, 3 and 4. 4 tabs., 11 figs., 15 refs. (Author).

  12. Device for the nuclear reactor automatic start-up and power control

    International Nuclear Information System (INIS)

    Nikiforov, B.N.; Volkov, A.V.; Ogon'kov, A.I.

    1978-01-01

    A description and flowsheet of a reactor start-up and power-control automatic device containing no nonlinear elements with a relay characteristic are presented. The device consists of two independent channels for measuring the physical power and time (period) constant of the reactor. Requirements for the device are considered, based on the condition of a minimum permissible number of a servomechanism operations due to fluctuations of an input signal which appear because of the statistical nature of processes taking place in the reactor. It is noted that the threshold amplifier used in the device allows a considerable decrease of the reactor start-up time

  13. Success and risk factors in the pre-startup phase

    OpenAIRE

    Thurik, Roy; Bosma, Niels; Gelderen, Marco

    2003-01-01

    textabstractWhy does one person actually succeed in starting a business, while a second person gives up? In order to answer this question, a sample of 517 nascent entrepreneurs (people in the process of setting up a business) was followed over a three year period. After this period, it was established that 195 efforts were successful and that 115 startup efforts were abandoned. Our research focuses on estimating the relative importance of a variety of approaches and variables in explaining pr...

  14. FFTF startup: status and results

    International Nuclear Information System (INIS)

    Noordhoff, B.H.; Moore, C.E.

    1980-03-01

    Startup testing on the Fast Flux Test Facility (FFTF) during the past three years has progressed beyond initial criticality toward the principal goal of power demonstration in 1980. An overview is presented of technical results to date and project plans to achieve power demonstration and complete the startup test program

  15. Simulation of SBWR startup transient and stability

    International Nuclear Information System (INIS)

    Cheng, H.S.; Khan, H.J.; Rohatgi, U.S.

    1998-01-01

    The Simplified Boiling Water Reactor (SBWR) designed by General Electric is a natural circulation reactor with enhanced safety features for potential accidents. It has a strong coupling between power and flow in the reactor core, hence the neutronic coupling with thermal-hydraulics is specially important. The potential geysering instability during the early part of a SBWR startup at low flow, low power and low pressure is of particular concern. The RAMONA-4B computer code developed at Brookhaven National Laboratory (BNL) for the SBWR has been used to simulate a SBWR startup transient and evaluate its stability, using a simplified four-channel representation of the reactor core for the thermal-hydraulics. This transient was run for 20,000 sec (5.56 hrs) in order to cover the essential aspect of the SBWR startup. The simulation showed that the SBWR startup was a very challenging event to analyze as it required accurate modeling of the thermal-hydraulics at low pressures. This analysis did not show any geysering instability during the startup, following the startup procedure as proposed by GE

  16. Study on secondary shutdown systems in Tehran research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jalali, H.R.; Fadaei, A.H., E-mail: Fadaei_amir@aut.ac.ir; Gharib, M.

    2015-09-15

    Highlights: • A study was undertaken to summarize the techniques for secondary shutdown systems (SSS). • Neutronic calculation performed for proposed systems as SSS. • Dumping the heavy water stored in the reflector vessel is capable to shut down reactor. • Neutronic and transient calculation was done for validating the selected SSS. • All calculation shown that this system has advantages in safety and neutron economy. - Abstract: One important safety aspect of any research reactor is the ability to shut down the reactor. Usually, research reactors, currently in operation, have a single shutdown system based on the simultaneous insertion of the all control rods into the reactor core through gravity. Nevertheless, the International Atomic Energy Agency currently recommends use of two shutdown systems which are fully independent from each other to guarantee secure shutdown when one of them fails. This work presents an investigative study into secondary shutdown systems, which will be an important safety component in the research reactor and will provide another alternative way to shut down the reactor emergently. As part of this project, a study was undertaken to summarize the techniques that are currently used at world-wide research reactors for recognizing available techniques to consider in research reactors. Removal of the reflector, removal of the fuels, change in critical shape of reactor core and insertion of neutron absorber between the core and reflector are selected as possible techniques in mentioned function. In the next step, a comparison is performed for these methods from neutronic aspects. Then, chosen method is studied from the transient behavior point of view. Tehran research reactor which is a 5 MW open-pool reactor selected as a case study and all calculations are carried out for it. It has 5 control rods which serve the purpose of both reactivity control and shutdown of reactor under abnormal condition. Results indicated that heavy

  17. CERN Vacuum-System Activities during the Long Shutdown 1: The LHC’s Injector Chain

    CERN Document Server

    Ferreira, J A

    2014-01-01

    During the long shutdown 1 (LS1), several maintenance, consolidation and upgrade activities have been carried out in LHC’s injector chain. Each machine has specific vacuum requirements and different history, which determine the present status of the vacuum components, their maintenance and consolidation needs. The present work presents the priorities agreed at the beginning of the LS1 period and their implementation. Of particular relevance are the interventions in radioactive controlled areas where several leaks due to stress corrosions stopped the operations in the past years. The strategy to reduce the collective dose is presented, in particular the use of remote controlled robots. An important part of the work performed during this period involves supporting other teams (acceptance tests, new equipment installation, etc.). Finally, as a result of the LS1 experience, a medium to long term strategy is depicted, focusing on the preparation of the next shutdown (LS2) and the integration of LINAC4 in the in...

  18. Criteria for remote shutdown for light water reactors

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    This Standard provides design criteria which require that: (1) specific controls and monitoring equipment shall be provided for achieving and maintaining the plant in a safe shutdown condition; (2) these controls be installed at a location (or locations) that is physically remote from the control room and cable spreading areas; (3) simultaneous control from both locations shall be prevented by administrative controls or devices for transfer of control from the control room to the remote location(s); and (4) the remote controls be used as defense-in-depth measure in addition to the control room shutdown controls and as a minimum shall provide for one complete channel of shutdown equipment

  19. CAREM-25 Reactor Second Shutdown System Consolidation Analysis

    International Nuclear Information System (INIS)

    Gimenez, Marcelo; Zanocco, Pablo; Schlamp, Miguel

    2000-01-01

    CAREM Reactor Second Shutdown System (SSS) injects boron into the primary circuit in case of First Shutdown System failure in order to stop the nuclear reaction and to maintain the core in a safe condition during cold shutdown.It also has another safety function which is to inject water in the primary system at any pressure in case of LOCA.Different system requirements are analyzed during a SSS spurious trip and LOCA's transients.Two different alternatives are presented for the stand by condition pressurized system, they are solid mode and hot water layer. Both cases fulfill the design requirements from the safety point of view

  20. Certificate for Safe Emergency Shutdown of Wind Turbines

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Svenstrup, Mikael; Pedersen, Andreas Søndergaard

    2013-01-01

    To avoid damage to a wind turbine in the case of a fault or a large wind gust, a detection scheme for emergency shutdown is developed. Specifically, the concept of a safety envelope is introduced. Within the safety envelope, the system can be shutdown without risking structural damage to the turb...

  1. Environmental mitigation for SCC initiation of BWR core internals by hydrogen injection during start-up

    International Nuclear Information System (INIS)

    Dozaki, K.; Abe, A.; Nagata, N.; Takiguchi, H.

    2004-01-01

    Hydrogen injection into the reactor water has been applied to many BWR power stations. Since hydrogen injected accelerates recombination of oxidant generated by water radiolysis, oxidant concentration, such as dissolved oxygen concentration in reactor water can be reduced. As the result of the reduction of oxidant concentration, Electrochemical Corrosion Potential (ECP) at the surface of structural material can be lowered. Lowered ECP moderates Stress Corrosion Cracking (SCC) sensitivity of structural materials, such as stainless steels. As usual, hydrogen injection system begins to work after the plant start-up is finished, when the condition of normal operation is established. Accordingly, Hydrogen Water Chemistry (HWC) does not cover all the period of plant operation. As far as SCC crack growth is considered, loss of HWC during plant start-up does not result in significant crack growth, because of duration of plant start-up is much shorter than that of plant normal operation, when HWC condition is being satisfied. However, the reactor water environment and load conditions during a plant start-up may contribute to the initiation of SCC. It is estimated that the core internals are subjected to the strain rate that may cause susceptibility to SCC initiation during start-up. Dissolved oxygen (DO) and hydrogen peroxide (H 2 O 2 ) has a peak, and ECP is in high levels during start-up. Therefore it is beneficial to perform hydrogen injection during start-up as well in order to suppress SCC initiation. We call it HWC During Start-up (HDS) here. (orig.)

  2. Lean Start-up in Established Companies

    DEFF Research Database (Denmark)

    Goduscheit, René Chester

    2018-01-01

    Lean start-up is an emergent perspective on how entrepreneurs can bring new products and services to the market. This approach challenges the dominant role of lengthy business plans, linear product development processes, and seeking complete overview of the potential of the new products....../services before market launch. Instead it suggests that start-ups could benefit from a ‘minimum-viable product’ approach where products and services are launched when they contain critical features. The emphasis in the lean start-up approach is on business models rather than the elaborate business plan...... at the companies (strategy meetings, development workshops etc.). The aim is to shed light on the implications for companies that seek to employ lean start-up. These implications will be aimed at aspects like innovation management, organizational structure, customer relations etc....

  3. Safety aspects of unplanned shutdowns and trips

    International Nuclear Information System (INIS)

    1986-05-01

    The issue of unplanned shutdowns and trips is receiving increased attention worldwide in view of its importance to plant safety and availability. There exists significant variation in the number of forced shutdowns for nuclear power plants of the same type operating worldwide. The reduction of the frequency of these events will have safety benefits in terms of reducing the frequency of plant transients and the challenges to the safety systems, and the risks of possible incidents. This report provides an insight into the causes of unplanned shutdowns experienced in operating nuclear power plants worldwide, the good practices that have been found effective in minimizing their occurrence, and the measures that have been taken to reduce these events. Specific information on the experiences, approaches and practices of some countries in dealing with this issue is presented in Appendix A

  4. Start-up simulations of the PULSAR pulsed tokamak reactor

    International Nuclear Information System (INIS)

    Werley, K.A.; Bathke, C.G.

    1993-01-01

    Start-up conditions are examined for a pulsed tokamak reactor that uses only inductively driven plasma current (and bootstrap current). A zero-dimensional (profile-averaged) model containing plasma power and particle balance equations is used to study several aspects of plasma start-up, including: (1) optimization of the start-up pathway; (2) tradeoffs of auxiliary start-up heating power versus start-up time; (3) volt-second consumption; (4) thermal stability of the operating point; (5) estimates of the diverter heat flux and temperature during the start-up transient; (6) the sensitivity of the available operating space to allowed values of the H confinement factor; and (7) partial-power operations

  5. Reliability Centered Maintenance (RCM) Methodology and Application to the Shutdown Cooling System for APR-1400 Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Faragalla, Mohamed M.; Emmanuel, Efenji; Alhammadi, Ibrahim; Awwal, Arigi M.; Lee, Yong Kwan [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2016-10-15

    Shutdown Cooling System (SCS) is a safety-related system that is used in conjunction with the Main Steam and Main or Auxiliary Feedwater Systems to reduce the temperature of the Reactor Coolant System (RCS) in post shutdown periods from the hot shutdown operating temperature to the refueling temperature. In this paper RCM methodology is applied to (SCS). RCM analysis is performed based on evaluation of Failure Modes Effects and Criticality Analysis (FME and CA) on the component, system and plant. The Logic Tree Analysis (LTA) is used to determine the optimum maintenance tasks. The main objectives of RCM is the safety, preserve the System function, the cost-effective maintenance of the plant components and increase the reliability and availability value. The RCM methodology is useful for improving the equipment reliability by strengthening the management of equipment condition, and leads to a significant decrease in the number of periodical maintenance, extended maintenance cycle, longer useful life of equipment, and decrease in overall maintenance cost. It also focuses on the safety of the system by assigning criticality index to the various components and further selecting maintenance activities based on the risk of failure involved. Therefore, it can be said that RCM introduces a maintenance plan designed for maximum safety in an economical manner and making the system more reliable. For the SCP, increasing the number of condition monitoring tasks will improve the availability of the SCP. It is recommended to reduce the number of periodic maintenance activities.

  6. University Start-ups: A Better Business Model

    Science.gov (United States)

    Dehn, J.; Webley, P. W.

    2015-12-01

    Many universities look to start-up companies as a way to attract faculty, supporting research and students as traditional federal sources become harder to come by. University affiliated start-up companies can apply for a broader suite of grants, as well as market their services to a broad customer base. Often university administrators see this as a potential panacea, but national statistics show this is not the case. Rarely do universities profit significantly from their start-ups. With a success rates of around 20%, most start-ups end up costing the university money as well as faculty-time. For the faculty, assuming they want to continue in academia, a start-up is often unattractive because it commonly leads out of academia. Running a successful business as well as maintaining a strong teaching and research load is almost impossible to do at the same time. Most business models and business professionals work outside of academia, and the models taught in business schools do not merge well in a university environment. To mitigate this a new business model is proposed where university start-ups are aligned with the academic and research missions of the university. A university start-up must work within the university, directly support research and students, and the work done maintaining the business be recognized as part of the faculty member's university obligations. This requires a complex conflict of interest management plan and for the companies to be non-profit in order to not jeopardize the university's status. This approach may not work well for all universities, but would be ideal for many to conserve resources and ensure a harmonious relationship with their start-ups and faculty.

  7. Perspectives on Low Power and Shutdown Risk

    International Nuclear Information System (INIS)

    Camp, Allen L.; Whitehead, Donnie W.; Wheeler, Timothy A.; Lehner, John; Chu, Tsong-Lun; Lois, Erasmai; Drouin, Mary

    2000-01-01

    This paper presents results from a program sponsored by the US Nuclear Regulatory Commission to examine the risks from low power and shutdown operations. Significant progress has been made by the industry in reducing such risks; however, important operational events continue to occur. Current perceptions of low power and shutdown risks are discussed in the paper along with an assessment of the current methods for understanding important events and quantifying their associated risk

  8. Ageing significantly at Temelin start-up process

    International Nuclear Information System (INIS)

    Brumovsky, M.; Zdarek, J.; Hahn, J.

    2002-01-01

    Full text: NPP Temelin is a unique case in Plant Life Management Programme application as it is now only in the period of start-up and thus all measures can be easily prepared and implemented in advance based on the experience of similar plants already in operation. Detailed analyses of potential damaging mechanisms as well as of initial conditions and properties of main components have been already done. Regarding this analysis, several measures have been prepared and put into operation: List of important parameters to be measured, saved and periodically analysed have been prepared - some of these parameters are measured in the framework of standard I and C system; new sets of sensors were installed for some additional ones; Special software for on-line evaluation of stress/temperature conditions and subsequently also fatigue damage in some chosen parts (with flow stratification etc.) have been installed and during reactor start-up tests have been checked; Surveillance specimen programme for reactor pressure vessel material monitoring was modified for better and fuller characterisation of material changes during operation; Ex-vessel neutron flux measurement has been established as a part of surveillance specimen programme. The whole Plant Life Management Programme is governed by a special PLIM Group in the plant with necessary links and responsibilities and rules with other necessary plant departments. (author)

  9. Growth Hacking for Startups : How Growth Hacking can utilised for growing startups

    OpenAIRE

    Lee, Jin

    2016-01-01

    In the era of start-ups, many failed to put out their prototypes or products to the market due to lack of funds or experience in marketing. Growth Hacking is a tool that start-ups can benefit from if they learn what Growth Hacking is and how to implement it. The aim of this thesis is to explore what Growth Hacking is and how to implement it for the commissioner CubiCasa Oy. A couple of Growth Hacking tactics are used for CubiCasa Oy and the process of implementation and findings are rec...

  10. Italy: Analysis of Solutions for Passively Actuated Safety Shutdown Devices

    International Nuclear Information System (INIS)

    Burgazzi, L.

    2015-01-01

    This article looks at different special shutdown systems specifically engineered for prevention of severe accidents, to be implemented on Fast Reactors, with main focus on the investigation of the performance of the self-actuated shutdown systems in Sodium Fast Reactors. The passive shut-down systems are designed to shut-down system only by inherent passive reactivity feedback mechanism, under unprotected accident conditions, implying failure of reactor protection system. They are conceived to be self-actuated without any signal elaboration, since the actuation of the system is triggered by the effects induced by the transient like material dilatation, in case of overheating of the coolant for instance, according to Fast Reactor design to meet the safety requirements

  11. Using dew points to estimate savings during a planned cooling shutdown

    Science.gov (United States)

    Friedlein, Matthew T.; Changnon, David; Musselman, Eric; Zielinski, Jeff

    2005-12-01

    In an effort to save money during the summer of 2003, Northern Illinois University (NIU) administrators instituted a four-day working week and stopped air conditioning buildings for the three-day weekends (Friday through Sunday). Shutting down the air conditioning systems caused a noticeable drop in electricity usage for that part of the campus that features in our study, with estimated total electricity savings of 1,268,492 kilowatt-hours or 17% of the average usage during that eight-week period. NIU's air conditioning systems, which relied on evaporative cooling to function, were sensitive to dew point levels. Greatest savings during the shutdown period occurred on days with higher dew points. An examination of the regional dew point climatology (1959 2003) indicated that the average summer daily dew point for 2003 was 14.9°C (58.8°F), which fell in the lowest 20% of the distribution. Based on the relationship between daily average dew points and electrical usage, a predictive model that could estimate electrical daily savings was created. This model suggests that electrical savings related to any future three-day shutdowns over summer could be much greater in more humid summers. Studies like this demonstrate the potential value of applying climatological information and of integrating this information into practical decision-making.

  12. Reactor Shutdown Mechanism by Top-mounted Hydraulic System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Haun; Cho, Yeong Garp; Choi, Myoung Hwan; Lee, Jin Haeng; Huh, Hyung; Kim, Jong In [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    There are two types of reactor shutdown mechanisms in HANARO. One is the mechanism driven by a hydraulic system, and the other is driven by a stepping motor. In HANARO, there are four Control Rod Drive Mechanisms (CRDMs) with an individual step motor and four Shutoff (SO) Units with an individual hydraulic system located at the top of reactor pool. The absorber rods in SO units are poised at the top of the core by the hydraulic force during normal operation. The rods of SO units drop by gravity as the first reactor showdown mechanism when a trip is commended by the reactor protection system (RPS). The rods in CRDMs also drop by gravity together as a redundant shutdown mechanism. When a trip is commended by the reactor regulating system (RRS), the absorber rods of CRDM only drop; while the absorber rods of SO units stay at the top of the core by the hydraulic system. The reactivity control mechanisms of in JRTR, one of the new research reactor with plate type fuels, consist of four CRDMs driven by an individual step motor and two second shutdown drive mechanisms (SSDMs) driven by an individual hydraulic system as shown in Fig. 1. The CRDMs act as the first reactor shutdown mechanism and reactor regulating as well. The top-mounted SSDM driven by the hydraulic system for the JRTR is under design in KAERI. The SSDM provides an alternate and independent means of reactor shutdown. The second shutdown rods (SSRs) of the SSDM are poised at the top of the core by the hydraulic system during the normal operation and drop by gravity for the reactor trip. Based on the proven technology of the design, operation and maintenance for HANARO, the SSDM for the JRTR has been optimized by the design improvement from the experience and test. This paper aims for the introduction of the SSDM in the process of the basic design. The major differences of the shutdown mechanisms by the hydraulic system are compared between HANARO and JRTR, and the design features, system, structure and

  13. Experience in the Kola NPP start-up works

    International Nuclear Information System (INIS)

    Zakharov, S.I.; Omel'chuk, V.V.; Bodrukhin, Yu.M.

    1984-01-01

    Main stages and peculiar features of maintenance and start-up works at WWER-440 type reactor NPPs described. Remarks revealed during complex equipment testing, physical and power start-up will be useful for arrangement of maintenance and start-up works at newly built NPPs

  14. An attempt for economic estimate of the shutdown of uranium production

    International Nuclear Information System (INIS)

    Jonchev, L.

    1997-01-01

    Uranium ore has been obtained since the end of 30s till 1992. No measures for protection of the environment and restricting the risk for the population during the production have been taken. Among the three possible models of shutting down the most inexpedient from economic point of view has been applied . It meant that the beginning of closing down took place far behind ceasing the production itself and the expenses for restoration were as big as fourteen times more in comparison to the two ones. The investments for prospecting and preparing new resources were lost. The whole process was made extremely inefficiently and unprofessionally. Because of the sudden closing down of production activities there was no enough time for gathering, processing and analyzing of necessary data, even the radioecological and hydro-ecological evaluations were doubtfully reliable. The shutdown of uranium production as worldwide practice takes place considering ALARA (As Low As Reasonably Achievable) principle. The aim is to achieve maximum possible results by minimum investments taking into account the radioecological risk, socially accounted for and psychologically conditioned expenses. There is no statement of the radioecological risk in the preliminary evaluations of the uranium mines in Bulgaria. The investment funds for the period 1992-1996 were about 2.1 bill. leva, (equally allocated for each year) which was about 46.5 mil. US$. Because of inflation process the investments crucially decreased during the last years when most capital-intensive activities had to be carried out - the engineering shutdown and land-reclamations procedures. The biggest share of investments (about 30 mil. US$) was for environmental status maintenance, 2.5 times less (about 13 mil. US$) - for technical shutdown and only 2.1 mil. US$ - for land reclamation. The investments for the shutdown process referred to the whole production obtained were only 2.5 US$/kg U 3 O 8 while the most effective model

  15. Energy losses on tokamak startup

    International Nuclear Information System (INIS)

    Murray, J.G.; Rothe, K.E.; Bronner, G.

    1983-01-01

    During the startup of a tokamak reactor using poloidal field (PF) coils to induce plasma currents, the conducting structures carry induced currents. The associated energy losses in the circuits must be provided by the startup coils and the PF system. This paper provides quantitative and comparitive values for the energies required as a function of the thickness or resistivity of the torus shells

  16. Downstream passage and impact of turbine shutdowns on survival of silver American Eels at five hydroelectric dams on the Shenandoah River

    Science.gov (United States)

    Eyler, Sheila; Welsh, Stuart A.; Smith, David R.; Rockey, Mary

    2016-01-01

    Hydroelectric dams impact the downstream migrations of silver American Eels Anguilla rostrata via migratory delays and turbine mortality. A radiotelemetry study of American Eels was conducted to determine the impacts of five run-of-the-river hydroelectric dams located over a 195-km stretch of the Shenandoah River, Virginia–West Virginia, during fall 2007–summer 2010. Overall, 96 radio-tagged individuals (mean TL = 85.4 cm) migrated downstream past at least one dam during the study. Most American Eels passed dams relatively quickly; over half (57.9%) of the dam passage events occurred within 1 h of reaching a dam, and most (81.3%) occurred within 24 h of reaching the dam. Two-thirds of the dam passage events occurred via spill, and the remaining passage events were through turbines. Migratory delays at dams were shorter and American Eels were more likely to pass via spill over the dam during periods of high river discharge than during low river discharge. The extent of delay in migration did not differ between the passage routes (spill versus turbine). Twenty-eight American Eels suffered turbine-related mortality, which occurred at all five dams. Mortality rates for eels passing through turbines ranged from 15.8% to 40.7% at individual dams. Overall project-specific mortality rates (with all passage routes combined) ranged from 3.0% to 14.3%. To protect downstream-migrating American Eels, nighttime turbine shutdowns (1800–0600 hours) were implemented during September 15–December 15. Fifty percent of all downstream passage events in the study occurred during the turbine shutdown period. Implementation of the seasonal turbine shutdown period reduced cumulative mortality from 63.3% to 37.3% for American Eels passing all five dams. Modifying the turbine shutdown period to encompass more dates in the spring and linking the shutdowns to environmental conditions could provide greater protection to downstream-migrating American Eels.

  17. Ignited tokamak devices with ohmic-heating dominated startup

    International Nuclear Information System (INIS)

    Cohn, D.R.; Bromberg, L.; Jassby, D.L.

    1986-01-01

    Startup of tokamaks such that the auxiliary heating power is significantly less than the ohmic heating power at all times during heating to ignition can be referred to as ''Ohmic-heating dominated startup.'' Operation in this mode could increase the certainty of heating to ignition since energy confinement during startup may be described by present scaling laws for ohmic heating. It could also reduce substantially the auxiliary heating power (the required power may be quite large for auxiliary-heating dominated startup). These advantages might be realized without the potentially demanding requirements for pure ohmic heating to ignition. In this paper the authors discuss the requirements for ohmic-heating dominated startup and present illustrative design parameters for compact experiment ignition devices that use high performance copper magnets

  18. Editorial: Startups (February 2010

    Directory of Open Access Journals (Sweden)

    Dru Lavigne

    2010-01-01

    Full Text Available Bob Sutor, Vice President of the Open Source and Linux division at IBM, recently stated that "there doesn't seem to be very many good guides about the nuts and bolts of starting an open source business". He speculates that one reason is that "there is no one way to start and run a business that involves open source". The authors in this issue of the OSBR are serial entrepreneurs, startup founders, and professionals who provide services to and interact daily with startups.

  19. COMPUTING SERVICES DURING THE ANNUAL CERN SHUTDOWN

    CERN Multimedia

    2000-01-01

    As in previous years, computing services run by IT division will be left running unattended during the annual shutdown. The following points should be noted. No interruptions are scheduled for local and wide area networking and the ACB, e-mail and unix interactive services. Maintenance work is scheduled for the NICE home directory servers and the central Web servers. Users must, therefore, expect service interruptions. Unix batch services will be available but without access to HPSS or to manually mounted tapes. Dedicated Engineering services, general purpose database services and the Helpdesk will be closed during this period. An operator service will be maintained and can be reached at extension 75011 or by email to: computer.operations@cern.ch Users should be aware that, except where there are special arrangements, any major problems that develop during this period will most likely be resolved only after CERN has reopened. In particular, we cannot guarantee backups for Home Directory files for eithe...

  20. Stabilization and shutdown of Oak Ridge National Laboratory's Radioisotopes Production Facility

    International Nuclear Information System (INIS)

    Eversole, R.E.

    1992-01-01

    The Oak Ridge National Laboratory (ORNL) has been involved in the production and distribution of a variety of radioisotopes for medical, scientific and industrial applications since the late 1940s. Production of these materials was concentrated in a number of facilities primarily built in the 1950s and 1960s. Due to the age and deteriorating condition of these facilities, it was determined in 1989 that it would not be cost effective to upgrade these facilities to bring them into compliance with contemporary environmental, safety and health standards. The US Department of Energy (DOE) instructed ORNL to halt the production of isotopes in these facilities and maintain the facilities in safe standby condition while preparing a stabilization and shutdown plan. The goal was to place the former isotope production facilities in a radiologically and industrially safe condition to allow a 5-year deferral of the initiation of environmental restoration (ER) activities. In response to DOE's instructions, ORNL identified 17 facilities for shutdown, addressed the shutdown requirements for each facility, and prepared and implemented a three-phase, 4-year plan for shutdown of the facilities. The Isotopes Facilities Shutdown Program (IFSP) office was created to execute the stabilization and shutdown plan. The program is entering its third year in which the actual shutdown of the facilities is initiated. Accomplishments to date have included consolidation of all isotopes inventory into one facility, DOE approval of the IFSP Environmental Assessment (EA), and implementation of a detailed management plan for the shutdown of the facilities

  1. Entrepreneurial patent management in pharmaceutical startups.

    Science.gov (United States)

    Holgersson, Marcus; Phan, Tai; Hedner, Thomas

    2016-07-01

    Startups fill an increasingly important role as innovators in the pharmaceutical industry, and patenting is typically central to their success. This article aims to explore patent management in pharmaceutical startups. The results show that startups need to deal with several challenges related to patenting and an 'entrepreneurial' approach to patent management is called for. Resource constraints, venture capital provision, exits and other conditions and events must be readily considered in the patent management process to build a successful pharmaceutical venture, something that could benefit the pharmaceutical industry as a whole. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Guidelines for e-Startup Promotion Strategy

    Directory of Open Access Journals (Sweden)

    Valerio De Simone

    2015-04-01

    Full Text Available Abstract Startup businesses have always played an important role in the global economy, but recently their importance has grown significantly. For this reason, governments around the world have amended regulation and created incentives to encourage their development. However, statistics show that startups have an extremely high mortality rate, often due to a lack of strategic planning, wrong marketing investments or inefficient resource allocation. The purpose of this paper is to propose a decision-driven tool which will enable the creation of a successful promotional strategy. The proposed strategy is a three-stage process allowing startups to gradually eliminate non-optimal advertising formats. The first stage focuses on the analysis of the e-market where the startup operates. The second stage is dedicated to the economic environment that the new company will face relative to its available resources. Its aim is to reject overly expensive advertising formats by linking costs to availability of funds. The third and last stage is a cost effectiveness analysis, allowing the entrepreneur to identify the best advertising formats and using an impact-factor as a proxy of effectiveness. The proposed methodology has been applied to the case of an Italian early-stage startup for validation.

  3. Formation and removal of dioxins in a MSWI during different operating periods

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.C.; Hwang, J.F. [Center for Environmental, Safety, and Health Technology, Industrial Technology Research Institute, Hsin-Chu (Taiwan). Environmental Health and Air Pollution Division; Chang, M.B.; Chi, K.H. [National Central University, Chungli (Taiwan). Graduate Inst. of Environmental Engineering

    2004-09-15

    There was little literature to report the dioxin emission concentrations and characteristics during start-up and burndown periods. This research aims to establish the databases of dioxin concentrations in the flue gas and evaluate the dioxin removal efficiencies by air pollution control devices (APCDs) at different operating periods (during start-up, normal operating and burn down periods).

  4. 20 CFR 632.254 - Program startup.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Program startup. 632.254 Section 632.254 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INDIAN AND NATIVE AMERICAN EMPLOYMENT AND TRAINING PROGRAMS Summer Youth Employment and Training Programs § 632.254 Program startup...

  5. Shutdown cooling temperature perturbation test for analysis of potential flow blockages

    International Nuclear Information System (INIS)

    Handbury, J.; Newman, C.; Shynot, T.

    1996-01-01

    This paper details the methods and results of the 'shutdown cooling test' in October 1995. This novel test was conducted at PLGS while the reactor was shutdown and shutdown cooling (SDC) waster was recirculating to find potential channel blockages resulting from the introduction of wood debris. This test discovered most of the channels that contained major wood and metal debris. (author)

  6. Dampak Mentoring Pada Keberhasilan Start-Up Business: Studi Kasus Pada Start-Up Business di Indonesia [Mentoring the Impact of Success of a Start-Up Business: A Case Study of a Start-Up Business in Indonesia

    Directory of Open Access Journals (Sweden)

    Christina Yanita Setyawati

    2016-10-01

    Full Text Available Entrepreneurship is a highly developed science today, as well as in the world of education in Indonesia. Teaching entrepreneurship at the university level, especially at some universities in Surabaya, the second largest city in Indonesia, shows the positive impact that there were 74.03% of start-up businesses that survived and thrived in 2014. Based on the previous observation, some business start-ups are accompanied by a mentor. Mentoring is a process of forming and maintaining lasting relationships that develop intensively among seniors with juniors. The mentoring function includes career and psychosocial functions. The main purpose of this research is to study the relationship between mentoring and the success of a start-up business. This study is a quantitative descriptive study using a random sampling method to obtain 100 samples. The tool used to collect data was a questionnaire. The methodology used to analyze the quantitative description to test the hypothesis. The results of this study indicate that mentoring influences the success of a start-up business that was owned by university students in Surabaya, Indonesia by 32% and 78% was influenced by other variables.

  7. Electricity-market price and nuclear power plant shutdown: Evidence from California

    International Nuclear Information System (INIS)

    Woo, C.K.; Ho, T.; Zarnikau, J.; Olson, A.; Jones, R.; Chait, M.; Horowitz, I.; Wang, J.

    2014-01-01

    Japan's Fukushima nuclear disaster, triggered by the March 11, 2011 earthquake, has led to calls for shutting down existing nuclear plants. To maintain resource adequacy for a grid's reliable operation, one option is to expand conventional generation, whose marginal unit is typically fueled by natural-gas. Two timely and relevant questions thus arise for a deregulated wholesale electricity market: (1) what is the likely price increase due to a nuclear plant shutdown? and (2) what can be done to mitigate the price increase? To answer these questions, we perform a regression analysis of a large sample of hourly real-time electricity-market price data from the California Independent System Operator (CAISO) for the 33-month sample period of April 2010–December 2012. Our analysis indicates that the 2013 shutdown of the state's San Onofre plant raised the CAISO real-time hourly market prices by $6/MWH to $9/MWH, and that the price increases could have been offset by a combination of demand reduction, increasing solar generation, and increasing wind generation. - Highlights: • Japan's disaster led to calls for shutting down existing nuclear plants. • We perform a regression analysis of California's real-time electricity-market prices. • We estimate that the San Onofre plant shutdown has raised the market prices by $6/MWH to $9/MWH. • The price increases could be offset by demand reduction and renewable generation increase

  8. The accidents during shutdown conditions Temelin NPP

    International Nuclear Information System (INIS)

    Sykora, M.; Mlady, O.

    1996-01-01

    Two parallel activities oriented for the accidents during shutdown conditions are performed at Temelin NPP: Development of symptom based emergency operating procedures (EOPs) applicable for the accidents which could occur during operational modes 1 through 4; independent evaluation of plant safety as part of the Temelin Shutdown probabilistic assessment to define the accidents which could occur during mode 5 and 6 for which the EOPs must be extended. Both these activities are in progress now because Temelin plant is still in the construction phase

  9. ECRH-assisted start-up in ITER

    International Nuclear Information System (INIS)

    Lloyd, B.; Carolan, P.G.; Warrick, C.D.

    1996-07-01

    In ITER, the electric field applied for ionisation and to ramp up the plasma current may be limited to ∼ 0.3 V/m. In this case, based on established theories of the avalanche process, it is shown that ohmic breakdown in ITER is only possible over a narrow range of pressure and magnetic error field. Therefore, ECRH may be necessary to provide robust and reliable start-up. ECRH can ensure prompt breakdown over a wide range of prefill pressure and error field and can also give control over the initial time and location of breakdown. For ECRH-assisted start-up in ITER, the power and pulse length requirements are essentially determined by the need to ensure burnthrough, i.e. complete ionisation of hydrogen and the transition to high ionisation states of impurities. A 0-D code (with inclusion of some 1-D effects) has been developed to analyse burnthrough in ITER. The 0-D simulations indicate that control of the deuterium density is the key factor for ensuring successful start-up in ITER, where the effects of neutral screening and dynamic fuelling by the ex-plasma volume are also crucial. It is concluded that without ECRH, successful start-up will only be possible over a very restricted range of parameters but 3MW of absorbed ECRH power will ensure reasonably robust start-up for a broad range of conditions with beryllium impurity. In the case of carbon impurity, even with an absorbed ECRH power of 5MW one may be restricted to low prefill pressure and/or low carbon concentration for successful start-up. (Author)

  10. Fluid shut-down system for a nuclear reactor

    International Nuclear Information System (INIS)

    Barclay, F.W.; Frey, J.R.; Wilson, J.N.; Besant, R.W.

    1975-01-01

    A nuclear reactor shut-down system is described which comprises a fluidic vortex valve for releasably maintaining a liquid neutron poison outside of the reactor core, the poison being contained by a reservoir and biased by pressure for flow into poison tubes within the reactor. The upper ends of the poison tubes communicate with the supply port of the vortex valve. A continuous gas flow into the control port maintains normal controlled operation. Shut-down is effected by interruption of the control input. One embodiment comprises three groups of poison tubes and one vortex valve associated with each group wherein shut-down is effected by poison release in two out of the three groups. Preferably, each vortex valve comprises three control ports which operate on a ''voting'' or two-out-of-three basis. (Official Gazette)

  11. Retrofit of AECL CAN6 seals into the Pickering shutdown cooling pumps

    International Nuclear Information System (INIS)

    Rhodes, D.; Metcalfe, R.; Brown, G.

    1997-01-01

    The existing mechanical seals in the shutdown cooling (SDC) pumps at the eight-unit Pickering Nuclear Generating Station have caused as least seven forced outages in the last fifteen years. The SDC pumps were originally intended to run only during shutdowns, mostly at low pressure, except for short periods during routine testing of SDC isolation valves while the plant is operating at full pressure to verify that the emergency core injection system is available. Unfortunately, in practice, some SDC pumps must be run much more frequently than this to prevent overheating or freezing of components in the system while the plant is at power. This more severe service has decreased seal lifetime from about 8000 running hours to about 3000 running hours. Rather than tackling the difficult task of eliminating on-power running of the pumps, Pickering decided to install a more robust seal design that could withstand this. Through the process of competitive tender, AECL's CAN6 seal was chosen. This seal has a successful history in similarly demanding conditions in boiling water reactors in the USA. To supplement this and demonstrate there would be no 'surprises,' a 2000-hour test program was conducted. Testing consisted of simulating all the expected conditions, plus some special tests under abnormal conditions. This has given assurance that the seal will operate reliably in the Pickering shutdown cooling pumps. (author)

  12. Retrofit of AECL CAN6 seals into the Pickering shutdown cooling pumps

    International Nuclear Information System (INIS)

    Rhodes, D.; Metcalfe, R.; Brown, G.; Kiameh, P.; Burchett, P.

    1997-01-01

    The existing mechanical seals in the shutdown cooling (SDC) pumps at the eight-unit Pickering Nuclear Generating Station have caused at least seven forced outages in the last fifteen years. The SDC pumps were originally intended to run only during shutdowns, mostly at low pressure, except for short periods during routine testing of SDC isolation valves while the plant is operating at full pressure to verify that the emergency core injection system is available. Unfortunately, in practice, some SDC pumps must be run much more frequently than this to prevent overheating or freezing of components in the system while the plant is at power. This more severe service has decreased seal lifetime from about 8000 running hours to about 3000 running hours. Rather than tackling the difficult task of eliminating on-power running of the pumps, Pickering decided to install a more robust seal design that could withstand this. Through the process of competitive tender, AECL's CAN6 seal was chosen. This seal has a successful history in similarly demanding conditions in boiling water reactors in the USA. To supplement this and demonstrate there would be no 'surprises,' a 2000-hour test program was conducted. Testing consisted of simulating all the expected conditions, plus some special tests under abnormal conditions. This has given assurance that the seal will operate reliably in the Pickering shutdown cooling pumps. (author)

  13. Research nuclear reactor start-up simulator

    International Nuclear Information System (INIS)

    Sofo Haro, M.; Cantero, P.

    2009-01-01

    This work presents the design and FPGA implementation of a research nuclear reactor start-up simulator. Its aim is to generate a set of signals that allow replacing the neutron detector for stimulated signals, to feed the measurement electronic of the start-up channels, to check its operation, together with the start-up security logic. The simulator presented can be configured on three independent channels and adjust the shape of the output pulses. Furthermore, each channel can be configured in 'rate' mode, where you can specify the growth rate of the pulse frequency in %/s. Result and details of the implementation on FPGA of the different functional blocks are given. (author)

  14. Thermal hydraulic behavior of SCWR sliding pressure startup

    International Nuclear Information System (INIS)

    Fu Shengwei; Zhou Chong; Xu Zhihong; Yang Yanhua

    2011-01-01

    The modification to ATHLET-SC code is introduced in this paper, which realizes the simulation of trans-critical transients using two-phase model. With the modified code, the thermal-hydraulic dynamic behavior of the mixed SCWR core during the startup process is simulated. The startup process is similar to the design of SCLWR-H sliding pressure startup. The results show that maximum temperature of cladding-surface does not exceed 650℃ in the whole startup process, and the sudden change of water properties in the trans-critical transients will not cause harmful influence to the heat transfer of the fuel cladding. (authors)

  15. Predicting start-up success with machine learning

    OpenAIRE

    Bento, Francisco Ramadas da Silva Ribeiro

    2018-01-01

    Start-ups are becoming the motor that moves our economy. Google, Apple, or more recently Airbnb and Uber are companies with tremendous impact in worldwide economy, social interactions and government. Over the past decade, both in the US and Europe, there has been an exponential growth in start-up formation. Thus, it seems a relevant challenge understanding what makes this type of high-risk ventures successful and as such, attractive to investors and entrepreneurs. Success for a start-up is de...

  16. Industry shutdown rates and permanent layoffs: evidence from firm-worker matched data

    Directory of Open Access Journals (Sweden)

    Kim P. Huynh

    2017-06-01

    Full Text Available Abstract Firm shutdown creates a turbulent situation for workers as it leads directly to layoffs for its workers. An additional consideration is whether a firm’s shutdown within an industry creates turbulence for workers at other continuing firms. Using data drawn from the Longitudinal Worker File, a Canadian firm-worker matched employment database, we investigate the impact of industry shutdown rates on workers at continuing firm. This paper exploits variation in shutdown rates across industries and within an industry over time to explain the rate of permanent layoffs and the growth of workers’ earnings. We find an increase in industry shutdown rates increases the probability of permanent layoffs and decreases earnings growth for workers at continuing firms.

  17. A import??ncia do mapeamento de processos em uma startup

    OpenAIRE

    Neves, Ana Carolina Coelho

    2016-01-01

    O artigo aborda a import??ncia de mapeamento de processos em uma startup. Com base no referencial te??rico sobre empreendedorismo, cen??rios, startups e mapeamento de processos, identificou-se a import??ncia do mapeamento de processos para as startups. Os objetivos de identificar se as startups possuem mapeamento de processo; identificar em qual momento de ciclo de vida uma startup deve desenvolver um mapeamento de processo; e identificar se o mapeamento de processos gera melhoria para uma st...

  18. Experience from start-ups of the first ANITA Mox plants.

    Science.gov (United States)

    Christensson, M; Ekström, S; Andersson Chan, A; Le Vaillant, E; Lemaire, R

    2013-01-01

    ANITA™ Mox is a new one-stage deammonification Moving-Bed Biofilm Reactor (MBBR) developed for partial nitrification to nitrite and autotrophic N-removal from N-rich effluents. This deammonification process offers many advantages such as dramatically reduced oxygen requirements, no chemical oxygen demand requirement, lower sludge production, no pre-treatment or requirement of chemicals and thereby being an energy and cost efficient nitrogen removal process. An innovative seeding strategy, the 'BioFarm concept', has been developed in order to decrease the start-up time of new ANITA Mox installations. New ANITA Mox installations are started with typically 3-15% of the added carriers being from the 'BioFarm', with already established anammox biofilm, the rest being new carriers. The first ANITA Mox plant, started up in 2010 at Sjölunda wastewater treatment plant (WWTP) in Malmö, Sweden, proved this seeding concept, reaching an ammonium removal rate of 1.2 kgN/m³ d and approximately 90% ammonia removal within 4 months from start-up. This first ANITA Mox plant is also the BioFarm used for forthcoming installations. Typical features of this first installation were low energy consumption, 1.5 kW/NH4-N-removed, low N₂O emissions, started up at Sundets WWTP in Växjö, Sweden, reached full capacity with more than 90% ammonia removal within 2 months from start-up. By applying a nitrogen loading strategy to the reactor that matches the capacity of the seeding carriers, more than 80% nitrogen removal could be obtained throughout the start-up period.

  19. DISP: Optimizations towards Scalable MPI Startup

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Huansong [Florida State University, Tallahassee; Pophale, Swaroop S [ORNL; Gorentla Venkata, Manjunath [ORNL; Yu, Weikuan [Florida State University, Tallahassee

    2016-01-01

    Despite the popularity of MPI for high performance computing, the startup of MPI programs faces a scalability challenge as both the execution time and memory consumption increase drastically at scale. We have examined this problem using the collective modules of Cheetah and Tuned in Open MPI as representative implementations. Previous improvements for collectives have focused on algorithmic advances and hardware off-load. In this paper, we examine the startup cost of the collective module within a communicator and explore various techniques to improve its efficiency and scalability. Accordingly, we have developed a new scalable startup scheme with three internal techniques, namely Delayed Initialization, Module Sharing and Prediction-based Topology Setup (DISP). Our DISP scheme greatly benefits the collective initialization of the Cheetah module. At the same time, it helps boost the performance of non-collective initialization in the Tuned module. We evaluate the performance of our implementation on Titan supercomputer at ORNL with up to 4096 processes. The results show that our delayed initialization can speed up the startup of Tuned and Cheetah by an average of 32.0% and 29.2%, respectively, our module sharing can reduce the memory consumption of Tuned and Cheetah by up to 24.1% and 83.5%, respectively, and our prediction-based topology setup can speed up the startup of Cheetah by up to 80%.

  20. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.

    2013-09-30

    This report fulfills the M2 milestone M2FT-13PN0912022, “Stranded Sites De-Inventorying Report.” In January 2013, the U.S. Department of Energy (DOE) issued the Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste (DOE 2013). Among the elements contained in this strategy is an initial focus on accepting used nuclear fuel from shutdown reactor sites. This focus is consistent with the recommendations of the Blue Ribbon Commission on America’s Nuclear Future, which identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses (BRC 2012). Shutdown sites are defined as those commercial nuclear power reactor sites where the nuclear power reactors have been shut down and the site has been decommissioned or is undergoing decommissioning. In this report, a preliminary evaluation of removing used nuclear fuel from 12 shutdown sites was conducted. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. These sites have no other operating nuclear power reactors at their sites and have also notified the U.S. Nuclear Regulatory Commission that their reactors have permanently ceased power operations and that nuclear fuel has been permanently removed from their reactor vessels. Shutdown reactors at sites having other operating reactors are not included in this evaluation.

  1. A Study on Fire Ignition Frequency of UCN 3 during Shutdown

    International Nuclear Information System (INIS)

    Kim, Kilyoo; Kang, DaeIl; Jang, Seung-Cheol

    2014-01-01

    A fire ignition frequency of UCN 3 during shutdown, i.e., during POS 3, 4, 5, 6 was calculated by using the new fire PSA method suggested in NUREG/CR-7114. As the fire ignition frequency during full power is calculated by the fixed ignition source and the transient ignition source, the one during shutdown is also calculated by the fixed and the transient ignition source. Since the fixed ignition source was already verified through the walkdown although the walkdown is for the fixed ignition source during full power, additional walkdown for the one during shutdown is not necessary. In the paper, how the fire ignition frequency of UCN 3 during shutdown was calculated is described. A fire ignition frequency of UCN 3 during shutdown, i.e., during POS 3, 4, 5, 6 was calculated by using the new fire PSA method suggested in NUREG/CR-7114. We make the transient ignition fire frequency of each BIN vary according to the daily work order of each POS

  2. Effect of the Modification of the Start-Up Sequence on the Thermal Stresses for a Microgas Turbine

    Directory of Open Access Journals (Sweden)

    Oscar Tenango-Pirin

    2016-01-01

    Full Text Available Microgas turbines (MGT are an alternative for small-scale energy production; however, their small size becomes a drawback since it enhances the heat transfer among their components. Moreover, heat transfer drives to temperature gradients which become higher during transient cycles like start-up. The influence of different start-up curves on temperature and thermal stresses of a microgas turbine was investigated. Stationary and rotational blades of the turbine were numerically simulated using CFD and FEM commercial codes. Conjugated heat transfer cases were solved for obtaining heat transfer from fluid toward the blades. Changes of temperature gradients within the blades during the start-ups were calculated under transient state with boundary conditions according to each curve to assess accurate thermal stresses calculations. Results showed that the modification of the start-up curves had an impact on the thermal stresses levels and on the time when highest stresses appeared on each component. Furthermore, zones highly stressed were located near the constraints of blades where thermal strains are restricted. It was also found that the curve that had a warming period at the beginning of the start-up allowed reducing the peaks of stresses making it more feasible and safer for the turbine start-up operation.

  3. On Startups and Doublethink

    DEFF Research Database (Denmark)

    Egan-Wyer, Carys; Muhr, Sara L.; Rehn, Alf

    2018-01-01

    a reaction to a perceived outrage or a power imbalance, but isin itselfa constitutive part of contemporary entrepreneurship,particularly as this is culturally constructed. We study this paradox, where a discourse of resistance becomes a productive part of entrepreneurial culture, by way of a case study...... of a successful startup. We analyze the manner in which people working in the startup utilize ‘doublethink’ to portray the organization both as resistance to an assumed, more corporate, ‘Other’ and also as a budding corporation unto itself. By doing so, we highlight how a discourse of resistance works as a value...

  4. Operating and maintenance experience of Dhruva secondary shutdown system

    International Nuclear Information System (INIS)

    Sharma, U.L.; Bharathan, R.

    1997-01-01

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

  5. Start-up period investigation of pilot-scale submerged membrane electro-bioreactor (SMEBR) treating raw municipal wastewater.

    Science.gov (United States)

    Hasan, Shadi W; Elektorowicz, Maria; Oleszkiewicz, Jan A

    2014-02-01

    Submerged membrane electro-bioreactor (SMEBR) is a new hybrid technology for wastewater treatment employing electrical field and microfiltration in a nutrient-removing activated sludge process. A pilot SMEBR system was located at the wastewater treatment plant in the City of l'Assomption (Quebec, Canada) with the objective of investigating the start-up period performance under variable organic loadings and environmental conditions with respect to effluent quality, membrane fouling, and sludge properties. The pilot SMEBR facility was fed with the raw de-gritted municipal wastewater. At steady state operation, the removal efficiencies of ammonia (as NH3(+)-N), phosphorus (as PO4(3-)-P), and COD were 99%, 99%, and 92%, respectively. No substantial increase in the monitored transmembrane pressure as 0.02kPad(-1) was reported. The time necessary to filter 100mL of the sludge sample has decreased by 78% after treatment whilst the sludge volume index averaged 119mLg(-1). Energy requirements were in the range of 1.1-1.6kWhm(-3) of wastewater. It was concluded that the SMEBR is a very competitive technology when compared to conventional membrane systems as it can enhance treatment performance to an appreciable extent, remove phosphorus and reduce fouling. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  6. Business Incubators - the savior of startups? : An exploratory study on knowledge acquisition in a business incubator from a startup perspective

    OpenAIRE

    Pettersson, Beatrice; Götsén, Anna

    2016-01-01

    Startups play a vital role in economic development, however, have a high rate of failure, partly due to insufficient knowledge resources. A business incubator is an institution aimed to assist startups with services and resources in order to facilitate their development. There is, however, a gap in previous research regarding knowledge flows and acquisition in business incubators. Furthermore, few scholars have conducted research from the startup perspective in this context. This study, there...

  7. Řízení rozvoje start-up společnosti

    OpenAIRE

    Paluch, Juraj

    2013-01-01

    Thesis deals with startup companies and their development methodology. The main aim is to present a model of startup company development. Within the theoretical part successful and unsuccessful businesses are analyzed and selected approaches to the development of startup companies are explained. In practical part, based on the findings a model for startup company development is proposed.

  8. Aloittelevan start-up yrittäjän opas rahoitukseen

    OpenAIRE

    Lamminsalo, Matti

    2015-01-01

    Opinnäytetyö käsittelee start-up rahoitusta ja siihen liittyviä toimintamalleja. Opinnäytetyön tuloksena on syntynyt opaskirja: Aloittelevan start-up yrittäjän opas rahoitukseen. Research about start-up ecosystem with investment aspect. As a result guidebook for start-up investment and how to raise a fund was writen.

  9. Shutdown chemistry optimization at Maanshan NPP

    International Nuclear Information System (INIS)

    Sun Yuanlung; Chuang Benjamin; Su Kouhwa; Kao Jueiting

    2009-01-01

    At Maanshan PWRs, a significant piping radiation buildup caused by crud burst from fuel surface in the beginning of RFO used to be blamed as a contribution to high personal exposures during outage. Therefore, several modifications on shutdown chemistry procedures such as, early lithium removal, rapid boration, dissolved hydrogen removal, extended RCP operation, and maintaining maximum let down flow, have been consecutively conducted since no.1RFO-16, 2006. The important operational and chemical parameters of modified shutdown chemistry procedures adopted in no.2 RFO-17, 2008 and superiority in low reading (2 mSv/hr) from let down heat exchangers area radiation monitor over 11mSv/hr of no.1 RFO-16 at the same area will be addressed in this paper. At the end of no.2 RFO-17, low personal exposures of 765 man-mSv (TLD)verified the absence of crud burst during shutdown chemistry process and broke records of Maanshan NPP as well. Even with a new job on PZR pre-emptive dissimilar weld overlay which exhausting 17.37% of total 797 man-mSv(TLD) in the latest no.1 RFO-18, 659 man-mSv (TLD) made another record low in the history of Maanshan. (author)

  10. Start-up Costs, Taxes and Innovative Entrepreneurship

    NARCIS (Netherlands)

    P. Darnihamedani (Pourya); J.H. Block (Jörn); S.J.A. Hessels (Jolanda); A. Simonyan (Aram)

    2015-01-01

    markdownabstract__Abstract__ Prior research suggests that start-up costs and taxes negatively influence entry into entrepreneurship. Yet, no distinction is made regarding the type of entrepreneurship, particularly innovative versus non-innovative entrepreneurship. Start-up costs, being one-off

  11. Start-up analysis for marketing strategy.

    Science.gov (United States)

    Griffith, M J; Baloff, N

    1984-01-01

    The complex start-up effect on utilization of health care services is too often overlooked or underestimated by marketing planners, leading to a range of negative consequences for both the users of services and the provider organization. Start-up analysis allows accurate estimation of these utilization effects for coordinated strategic planning among marketing finance, and operations.

  12. Tokamak start-up with electron-cyclotron heating

    International Nuclear Information System (INIS)

    Holly, D.J.; Prager, S.C.; Shepard, D.A.; Sprott, J.C.

    1981-01-01

    Experiments are described in which the start-up voltage in a tokamak is reduced by about a factor of two by the use of a modest amount of electron cyclotron resonance heating power for pre-ionization. The solution of the zero-dimensional start-up equations indicates that the effect is due to the high initial density which increases the rate at which the conductivity increases in the neutral-dominated initial plasma. The effect extrapolates favourably to larger tokamaks. A 50% reduction in the start-up volt-second requirement and impurity reflux is also observed. (author)

  13. Tokamak start-up with electron-cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Holly, D J; Prager, S C; Shepard, D A; Sprott, J C [Wisconsin Univ., Madison (USA)

    1981-11-01

    Experiments are described in which the start-up voltage in a tokamak is reduced by about a factor of two by the use of a modest amount of electron cyclotron resonance heating power for pre-ionization. The solution of the zero-dimensional start-up equations indicates that the effect is due to the high initial density which increases the rate at which the conductivity increases in the neutral-dominated initial plasma. The effect extrapolates favourably to larger tokamaks. A 50% reduction in the start-up volt-second requirement and impurity reflux is also observed.

  14. Letter report seismic shutdown system failure mode and effect analysis

    International Nuclear Information System (INIS)

    KECK, R.D.

    1999-01-01

    The Supply Ventilation System Seismic Shutdown ensures that the 234-52 building supply fans, the dry air process fans and vertical development calciner are shutdown following a seismic event. This evaluates the failure modes and determines the effects of the failure modes

  15. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, Steven J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Best, Ralph E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ross, Steven B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buxton, Kenneth A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); England, Jeffery L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McConnell, Paul E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Massaro, Lawrence M. [Fermi Research Alliance (FRA), Batavia, IL (United States); Jensen, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-30

    A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power plant sites was performed. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, and Vermont Yankee. The evaluation was divided into four components: Characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory A description of the on-site infrastructure at the shutdown sites An evaluation of the near-site transportation infrastructure and transportation experience at the shutdown sites An evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. The primary sources for the inventory of SNF and GTCC waste were the U.S. Department of Energy (DOE) spent nuclear fuel inventory database, industry publications such as StoreFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of on-site infrastructure and near-site transportation infrastructure and experience included information collected during site visits, information provided by managers at the shutdown sites, Facility Interface Data Sheets compiled for DOE in 2005, Services Planning Documents prepared for DOE in 1993 and 1994, industry publications such as Radwaste Solutions, and Google Earth. State staff, State Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative have participated in nine of the shutdown site visits. Every shutdown site was found to have at least one off-site transportation mode option for removing its SNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an

  16. Start-Up of a Pulsed Beam Free Electron Laser (FEL) Oscillator

    Science.gov (United States)

    1983-04-01

    By slightly increasing the frequency of the R.F. accelerating field, Wacc during the start-up period, i.e., decreasing the beam pulse separation, the...levels. The required fractional increase in Wacc is 16L 1- 6L2 1/Lbow 10 - 6 for the parameters of ref. (3,4). The same 6 effect may also be realized

  17. Inspection maintenance and planning of shutdown in thermal electric generating plants

    International Nuclear Information System (INIS)

    Dezordi, W.L.; Correa, D.A.; Kina, M.

    1984-01-01

    The schedule shutdown of an industrial plant and, more specifically, of an electrical generating station, is becoming increasingly important. The major parameters to be taken into account for the planning of such a shutdown are basically of economic-financial nature such as costs of the related services (materials, equipment, manpower, etc), loss of revenue caused by the station's shutdown as well as by the station availability, and other requirements expected from it by the Load Dispatch and consumers. Improving the equipment's performances and the station's availability are the fundamental objectives to be strived for. The authors present in this paper, in an abridged form, the planning tools used for thermal electric generating plants shutdowns for inspections, maintenance and design changes implementation. (Author) [pt

  18. 77 FR 75198 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

    Science.gov (United States)

    2012-12-19

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0299] Standard Format and Content for Post-Shutdown... regulatory guide (DG), DG-1272, ``Standard Format and Content for Post-shutdown Decommissioning Activities... Content for Post-shutdown Decommissioning Activities Report,'' which was issued in July 2000. DG-1271...

  19. 76 FR 81998 - Methodology for Low Power/Shutdown Fire PRA

    Science.gov (United States)

    2011-12-29

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0295] Methodology for Low Power/Shutdown Fire PRA AGENCY..., ``Methodology for Low Power/Shutdown Fire PRA--Draft Report for Comment.'' DATES: Submit comments by March 01... risk assessment (PRA) method for quantitatively analyzing fire risk in commercial nuclear power plants...

  20. Shutdowns/scrams at BWRs reported under new 1984 LER rule

    International Nuclear Information System (INIS)

    Mays, G.T.

    1985-01-01

    Operating experience data from nuclear power plants are essential for safety and reliability analyses. The Licensee Event Reports (LERs), submitted to the NRC by nuclear power plant utilities, contain much of this data. One of the significant aspects of the new LER rule includes the requirement to report all plant shutdowns whereas prior to 1984, not all shutdowns were reported as LERs. This paper reviews the shutdowns and scrams occurring during the first six months of 1984 at BWRs as reported under the new LER rule. The review focused on systems involved, causes, and personnel interactions

  1. 77 FR 68119 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Science.gov (United States)

    2012-11-15

    ..., which includes $497,092 in labor costs, no capital/startup costs, and $100,800 in operation and... maintain records of the occurrence and duration of any startup, shutdown, or malfunction in the operation...

  2. Genetic Counselors in Startup Companies: Redefining the Genetic Counselor Role.

    Science.gov (United States)

    Rabideau, Marina M; Wong, Kenny; Gordon, Erynn S; Ryan, Lauren

    2016-08-01

    Genetic counselors (GCs) have recently begun moving into non-clinic based roles in increasing numbers. A relatively new role for GCs is working for startup companies. Startups are newly established companies in the phase of developing and researching new scalable businesses. This article explores the experiences of four GCs working at different startup companies and aims to provide resources for GCs interested in learning more about these types of roles. The article describes startup culture, including a relatively flat organizational structure, quick product iterations, and flexibility, among other unique cultural characteristics. Financial considerations are described, including how to understand and evaluate a company's financial status, along with a brief explanation of alternate forms of compensation including stock options and equity. Specifically, the article details the uncertainties and rewards of working in a fast-paced startup environment that affords opportunities to try new roles and use the genetic counseling skill set in new ways. This article aims to aid GCs in determining whether a startup environment would be a good fit, learning how to evaluate a specific startup, and understanding how to market themselves for positions at startups.

  3. Comparison between MBR and SBR on Anammox start-up process from the conventional activated sludge.

    Science.gov (United States)

    Wang, Tao; Zhang, Hanmin; Gao, Dawen; Yang, Fenglin; Zhang, Guangyi

    2012-10-01

    Anammox start-up performances from the conventional activated sludge were compared between a MBR and SBR. Both the reactors successfully started up Anammox process. The start-up period in the MBR (59 days) was notably shorter than that in the SBR (101 days), and the max nitrogen (NH(4)(+)+NO(2)(-)) removal capacity of 345.2 mg N L(-1) d(-1) in the MBR was also higher than that of 292.0 mg N L(-1) d(-1) in the SBR. FISH analysis showed that Anammox bacteria predominated in both reactors. Phylogenetic analysis further disclosed that the MBR had the better biodiversity of Anammox bacteria and gained a higher ecological stability. Generally, the results showed that MBR exhibited a more excellent performance for Anammox start-up. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  4. Alternative Shutdown Panel. Amaraz Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Saenz de Santa Maria Valin, J.

    2016-07-01

    Between 2010 and 2014 the Nuclear Power Plant of Almaraz conducted one of the most complex projects in its history: The installation of an Alternative Shutdown Panel with the capability to stop the plant in case of fire in the Control room or in the Cable room. This project represented a great economic and organizational effort for the plant, but at the same time has been a great improvement in the safety of the installation, which was demonstrated by the achievement of a major milestone in the history of Almaraz: The actual shutdown from outside of the Control room. (Author)

  5. Training simulator for advanced gas-cooled reactor (AGR) shutdown sequence equipment

    International Nuclear Information System (INIS)

    Shankland, J.P.; Nixon, G.L.

    1978-01-01

    Successful shutdown of nuclear plant is of prime importance for both safety and economic reasons and large sums of money are spent on equipment to make shutdowns fully automatic, thus removing the possibility of operator errors. While this aim can largely be realized, one must consider the possibility of automatic equipment or plant failures when operators are required to take manual action, and off-line training facilities should be available to operating staff to minimize the risk of incorrect actions being taken. This paper presents the practice adopted at Hunterston 'B' Nuclear Power Station to solve this problem and concerns the computer-based training simulator for the Reactor Shutdown Sequence Equipment (RSSE) which was commissioned in January 1977. The plant associated with shutdown is briefly described and the reasoning which shows the need for a simulator is outlined. The paper also gives details of the comprehensive facilities available on the simulator and goes on to describe the form that shutdown training takes and the experience gained at this time. (author)

  6. Briu: A Coffee Roasting Startup

    OpenAIRE

    Beck, Maximilian

    2015-01-01

    The purpose of this study is to examine the German coffee market and its appropriateness as a new market to enter for the startup Company Briu. The company has been continuously growing since its initial start. The Chilean Coffee startup has since then looked for new markets opportunities in Europe. Their favored market is Germany. The research conducted in this paper is supposed to reveal the market its suitability for the company its expansion. The following key areas are assessed in order ...

  7. Dampak Mentoring Pada Keberhasilan Start-Up Business: Studi Kasus Pada Start-Up Business di Indonesia [Mentoring the Impact of Success of a Start-Up Business: A Case Study of a Start-Up Business in Indonesia

    OpenAIRE

    Christina Yanita Setyawati

    2016-01-01

    Entrepreneurship is a highly developed science today, as well as in the world of education in Indonesia. Teaching entrepreneurship at the university level, especially at some universities in Surabaya, the second largest city in Indonesia, shows the positive impact that there were 74.03% of start-up businesses that survived and thrived in 2014. Based on the previous observation, some business start-ups are accompanied by a mentor. Mentoring is a process of forming and maintaining lasting relat...

  8. 77 FR 10576 - Methodology for Low Power/Shutdown Fire PRA

    Science.gov (United States)

    2012-02-22

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0295] Methodology for Low Power/Shutdown Fire PRA AGENCY.../Shutdown Fire PRA.'' In response to request from members of the public, the NRC is extending the public... risk assessment (PRA) method for quantitatively analyzing fire risk in commercial nuclear power plants...

  9. V2I-based startup assistance system at signalized intersections

    Directory of Open Access Journals (Sweden)

    Jianqiang Wang

    2015-08-01

    Full Text Available Traffic delays are caused by unskilled vehicle operation and driver distraction during the startup process at signalized intersections. To address this issue, we propose a V2I-based driver assistance system that can acquire the current traffic signal status and provide drivers with startup assistance. This article presents the proposed system’s architecture and an assistance algorithm, which contains two types of driver assistance methods: startup prompting and automatic startup control. The automatic startup control method, based on fuzzy logic control, is validated in simulation tests. We also implement startup prompting using a prototype system and validate its performance in field tests. The test results suggest that the proposed assistance algorithm can help drivers start up their vehicles with less delay, which will significantly improve traffic efficiency.

  10. Development of self-actuated shutdown system using curie point electromagnet

    International Nuclear Information System (INIS)

    Kim, Tae Ryong; Park, Jin Ho

    1999-01-01

    An innovative concept for a passive reactor shutdown system, so called self-actuated shutdown system (SASS), is inevitably required for the inherent safety in liquid metal reactor, which is designed with the totally different concept from the usual reactor shutdown system in LWR. SASS using Curie point electromagnet (CPEM) was selected as the passive reactor shutdown system for KALIMER (Korea Advanced Liquid Metal Reactor). A mock-up of the SASS was designed, fabricated and tested. From the test it was confirmed that the mockup was self-actuated at the Curie point of the temperature sensing material used in the mockup. An articulated control rod was also fabricated and assembled with the CPEM to confirm that the control rod can be inserted into core even when the control rod guide tube is deformed due to earthquake. The operability of SASS in the actual sodium environment should be confirmed in the future. All the design and test data will be applied to the KALIMER design. (author)

  11. Design of shutdown system no.2 liquid poison injection system for 500 MWe PHWR

    International Nuclear Information System (INIS)

    Bhatnagar, S.; Balasubrahmanian, A.K.; Pillai, A.V.

    1997-01-01

    Defence in depth and two group system concepts form the basic design philosophy for the shutdown systems. There are two independent, diverse and fast acting shutdown systems provided for the 500 MWe PHWR. The design is based on fail-safe principle, sufficient component redundancy and on-line testing. Liquid poison injection system, as shutdown system 2, is newly developed for the 500 MWe PHWRs. The system operates by rapidly injecting gadolinium nitrate solution into bulk moderator using stored helium pressure thereby inserting negative reactivity. A high pressure helium supply tank which provides the energy for system actuation, is connected, through an array of fast acting valves in series-parallel arrangement, to the individual poison tanks storing gadolinium nitrate solution. The valves, belonging to three different channels of reactor Protection System 2, are the only active components in the system. The valves are fail safe and are periodically tested on-line without actually firing the system. The system comprising of in-core assemblies and the external process system has been engineered. Experimental work is being carried out by BARC for design validation and data generation. This paper describes the conceptual development, design basis, design parameters and detailed engineering of the system. (author)

  12. Morphological study of biomass during the start-up period of a fixed-bed anaerobic reactor treating domestic sewage

    Directory of Open Access Journals (Sweden)

    Cláudio Antonio Andrade Lima

    2005-09-01

    Full Text Available This work focused on a morphological study of the microorganisms attached to polyurethane foam matrices in a horizontal-flow anaerobic immobilized biomass (HAIB reactor treating domestic sewage. The experiments consisted of monitoring the biomass colonization process of foam matrices in terms of the amount of retained biomass and the morphological characteristics of the cells attached to the support during the start-up period. Non-fluorescent rods and cocci were found to predominate in the process of attachment to the polyurethane foam surface. From the 10th week of operation onwards, an increase was observed in the morphological diversity, mainly due to rods, cocci, and Methanosaeta-like archaeal cells. Hydrodynamic problems, such as bed clogging and channeling occurred in the fixed-bed reactor, mainly due to the production of extracellular polymeric substances and their accumulation in the interstices of the bed causing a gradual deterioration of its performance, which eventually led to the system's collapse. These results demonstrated the importance and usefulness of monitoring the dynamics of the formation of biofilm during the start-up period of HAIB reactors, since it allowed the identification of operational problems.Este trabalho apresenta um estudo morfológico de microrganismos aderidos à espuma de poliuretano em reator anaeróbio horizontal de leito fixo (RAHLF, aplicado ao tratamento de esgoto sanitário. O processo de colonização do suporte pela biomassa anaeróbia e as características morfológicas das células aderidas foram monitorados durante o período de partida do reator. Bacilos e cocos não fluorescentes foram predominantes no processo de aderência direta à espuma de poliuretano. Aumento na diversidade biológica foi observado a partir da 10ª semana de operação do reator, com predominância de bacilos, cocos e arqueas metanogênicas semelhantes a Methanosaeta. Problemas hidrodinâmicos, tais como formação de

  13. Cone penetrometer demonstration standard startup review checklist

    International Nuclear Information System (INIS)

    KRIEG, S.A.

    1998-01-01

    Startup readiness for the Cone Penetrometer Demonstration in AX Tank Farm will be verified through the application of a Standard Startup Review Checklist. This is a listing of those items essential to demonstrating readiness to start the Cone Penetrometer Demonstration in AX Tank Farm

  14. Annual report on experimental operations and maintenances of mock-up model test facility with a full-scale reaction tube for HTTR hydrogen production system in 2003 fiscal year (Contract research)

    International Nuclear Information System (INIS)

    Hayashi, Koji; Morisaki, Norihiro; Ohashi, Hirofumi; Kato, Michio; Aita, Hideki; Takeda, Tetsuaki; Nishihara, Tetsuo; Inaba, Yoshitomo; Takada, Shoji; Inagaki, Yoshiyuki

    2006-03-01

    This is a report on the experimental operations and maintenances of the mock-up test facility with a full-scale reaction tube for the HTTR hydrogen production system in 2003 fiscal year. The fourth and fifth experimental test operations were performed, from May to July and from October to December in 2003, for the following tests; (a) start-up and shutdown operation test, (b) process change test, (c) continuous hydrogen-production test and (d) chemical reaction shutdown test. From the results, a long time-range stability of the hydrogen production system was confirmed, a behavior of the helium-gas cooling system, consists of steam generator and radiator; during chemical reaction shutdown, was understood, and so on. Periodic inspections on boiler equipment and high-pressure gas production facilities were performed from end of July 2003. This report is summarized on outlines and results of the tests, outlines and results of the periodic inspections, and operation records of the mock-up test facility. (author)

  15. 40 CFR 63.1656 - Performance testing, test methods, and compliance demonstrations.

    Science.gov (United States)

    2010-07-01

    ... startup, shutdown, and malfunction in the calculation if the condition is described in the startup... of the sum of alarm times to the total operating time multiplied by 100. [64 FR 27458, May 20, 1999...

  16. Start-up Funding via Equity Crowdfunding in Germany

    DEFF Research Database (Denmark)

    Angerer, Martin; Brem, Alexander; Kraus, Sascha

    2017-01-01

    Entrepreneurs often struggle to find sufficient funding for their start-ups. A relatively new way for companies to attract capital is via an internet platform, locating investors who in return receive something in return for their ventures. Equity crowdfunding is one of several types of crowdfund......Entrepreneurs often struggle to find sufficient funding for their start-ups. A relatively new way for companies to attract capital is via an internet platform, locating investors who in return receive something in return for their ventures. Equity crowdfunding is one of several types...... of crowdfunding, and is also known as crowdinvesting in the German-speaking realm. This article predominantly advances the scientific knowledge regarding the success factors of equity crowdfunding for German start-ups. The study conducted nine qualitative interviews with start-ups and crowdinvesting platforms....... Its first result is that German start-ups select crowdinvesting because (1) it is a funding opportunity and (2) it has an expected marketing effect. To organize the results of relevant success factors, the Crowdinvesting Success Model was designed by the researchers. This supports German entrepreneurs...

  17. 30 CFR 57.8534 - Shutdown or failure of auxiliary fans.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shutdown or failure of auxiliary fans. 57.8534... Ventilation Underground Only § 57.8534 Shutdown or failure of auxiliary fans. (a) Auxiliary fans installed and... fan maintenance or fan adjustments where air quality is maintained in compliance with the applicable...

  18. PSA for the shutdown mode for nuclear power plants

    International Nuclear Information System (INIS)

    1994-06-01

    The meeting, which was attended by more than 75 participants from 20 countries, provided a broad discussion forum where all the currently active major shutdown PSA programmes were reviewed. The meeting also addressed the issues related to actual performance of shutdown PSA studies as well as insight gained from the studies. This document, which was prepared during the TCM, contains the results of extensive discussions which were held in specific working groups. The papers presented at the meeting provide a comprehensive overview of the state of the art of shutdown risk assessment and remedial measures taken to reduce the risk in outages. It is hoped that this document will be very useful to all individuals with interest in increasing safety during outages at NPPs. Refs, figs and tabs

  19. New Solutions to the Funding Dilemma of Technology Startups

    Directory of Open Access Journals (Sweden)

    Ali Kousari

    2011-05-01

    Full Text Available This article explores the current funding challenges facing technology startups and describes new models based on smaller investments and collective action. First, the advantages and disadvantages of traditional startup funding models are presented, with an emphasis on venture capital and angel investment. Next, an overview of existing seed funds, or seed accelerators, shows how entrepreneurs can leverage this approach to access subsequent rounds of funding and create successful ventures. Then, an overview of crowd funding is provided, including examples of companies that have adopted this approach to funding startups and their founders. Finally, the article presents the basis of a new approach that uses crowd funding as means of attracting investors to collectives. In these business ecosystems, startups are exposed to less risk and investors can benefit from attractive returns by investing in these promising startups.

  20. Core shutdown report: Subcycle K-14.1

    International Nuclear Information System (INIS)

    Gough, S.T.

    1992-05-01

    When a reactor is shut down, there is a set of rules that must be followed to guarantee that the reactor remains in a safe shutdown state. Some of these rules involve the cooling of heat generating assemblies before, during, and after charge-discharge (C ampersand D) operations. These rules ensure that C ampersand D operations will not endanger the integrity of the fuel or targets by allowing them to overheat. DPSOL 105-1225, Assembly Discharge and Forced Cooling Requirements, is the primary operations procedure that governs these cooling rules. The specific shutdown cooling limits that are input into this procedure are contained within this report

  1. Fast Startup of Semi-Pilot-Scale Anaerobic Digestion of Food Waste Acid Hydrolysate for Biogas Production.

    Science.gov (United States)

    Huang, Chao; Zhao, Cheng; Guo, Hai-Jun; Wang, Can; Luo, Mu-Tan; Xiong, Lian; Li, Hai-Long; Chen, Xue-Fang; Chen, Xin-De

    2017-12-27

    In this study, a fast startup of semi-pilot-scale anaerobic digestion of food waste acid hydrolysate for biogas production was carried out for the first time. During the period of fast startup, more than 85% of chemical oxygen demand (COD) can be degraded, and even more than 90% of COD can be degraded during the later stage of anaerobic digestion. During this anaerobic digestion process, the biogas yield, the methane yield, and the CH 4 content in biogas were 0.542 ± 0.056 m 3 /kg COD consumption , 0.442 ± 0.053 m 3 /kg COD consumption , and 81.52 ± 3.05%, respectively, and these values were high and stable. Besides, the fermentation pH was very stable, in which no acidification was observed during the anaerobic digestion process (outlet pH was 7.26 ± 0.05 for the whole anaerobic digestion). Overall, the startup of this anaerobic digestion can be completed in a short period (the system can be stable 2 days after the substrate was pumped into the bioreactor), and anaerobic digestion of food waste acid hydrolysate is feasible and attractive for industrial treatment of food waste and biogas production.

  2. Tokamak reactor startup power

    International Nuclear Information System (INIS)

    Weldon, D.M.; Murray, J.G.

    1983-01-01

    Tokamak startup with ohmic heating (OH)-induced voltages requires rather large voltages and power supplies. On present machines, with no radiofrequency (rf)-assist provisions, hundreds of volts have been specified for their designs. With the addition of electron cyclotron resonant heating (ECRH) assist, the design requirements have been lowered. To obtain information on the cost and complexity associated with this ECRH-assisted, OH-pulsed startup voltage for ignition-type machines, a trade-off study was completed. The Fusion Engineering Device (FED) configuration was selected as a model because information was available on the structure. The data obtained are applicable to all tokamaks of this general size and complexity, such as the Engineering Test Reactor

  3. The process of the start-up of a PWR nuclear power plant in the USA

    International Nuclear Information System (INIS)

    Rana, B.S.

    1977-01-01

    The procedure is described of putting into full operation the William B. Mc Guire nuclear power plant with two PWR reactors with an output of 2x3,411 MWt (2x1,220 MWe) supplied to the Duke Power Co. lock, stock and barrel. The basic specifications are shown of units I and II and the organization of start-up activities is described. The time schedule of preoperational and start-up tests is shown and testing is reviewed preceding the first fuel charge. Also described are tests related to the first start-up of a unit comprising the period of the first fuel charge, the initial critical state, low-power tests and tests with power gradually increased. In tests of the individual systems and components of the unit, operating regulations are verified and, if required, renewed, or new regulations are introduced. (B.S.)

  4. The Ecosystem of Startups as a Component of the Innovation Ecosystem

    Directory of Open Access Journals (Sweden)

    Sytnik Natalia I.

    2017-08-01

    Full Text Available The article analyzes the current theoretical perceptions of the ecosystem of startups and presents the author’s own vision of this entity. It has been proposed to consider the ecosystem of startups as a subsystem of the innovation ecosystem, which aims at creating innovative products and services by startup companies. The ecosystem of startups is an open dynamic system in which the backbone subject is a startup company at various stages of the life cycle. The sustenance subjects in an ecosystem are the organizations, associations and individuals that cause impacts, to varying degrees, on the establishing or development of startups. The activities of the subjects are carried out in the following directions: public regulation, financing, training, information, and infrastructure support for startups. The ecosystem consists of a number of economic, material-and-technical, market, and socio-cultural factors that directly or indirectly influence the actions of the subjects. The vital activity of the ecosystem of startups is maintained by the active interaction of the subjects, connected by a network of internal links with the environment and between themselves.

  5. 1-D hybrid code for FRM start-up

    International Nuclear Information System (INIS)

    Stark, R.A.; Miley, G.H.

    1982-01-01

    A one-D hybrid has been developed to study the start-up of the FRM via neutral-beam injection. The code uses a multi-group numerical model originally developed by J. Willenberg to describe fusion product dynamics in a solenoidal plasma. Earlier we described such a model for use in determining self-consistent ion currents and magnetic fields in FRM start-up. However, consideration of electron dynamics during start-up indicate that the electron current will oppose the injected ion current and may even foil the attempt to achieve reversal. For this reason, we have combined the multi-group ion (model) with a fluid treatment for electron dynamics to form the hybrid code FROST (Field Reversed One-dimensional STart-up). The details of this merger, along with sample results of operation of FROST, are given

  6. Model checking the FlexRay startup phase

    NARCIS (Netherlands)

    Cranen, S.

    2012-01-01

    This report describes a discrete-time model of the startup phase of a FlexRay network. The startup behaviour of this network is analysed in the presence of several faults. It is shown that in certain cases a faulty node can prevent the network from communicating altogether. One previously unknown

  7. Management of refuelling, modifications and accidental shut-down of nuclear power plant

    International Nuclear Information System (INIS)

    1996-01-01

    This document is the appendix of HAF 0300 (91) 'Code on the Safety of Nuclear Power Plant Operation', which was promulgated by the National Nuclear Safety Administration (NNSA) on March 2, 1994, and has the same legal effect. This appendix is applicable to establish the administrative management procedures for refuelling, modifications and accidental shut-down in the period of operation of pressurized water thermal neutron reactor of nuclear power plants. The NNSA shall be responsible for interpretation of this document

  8. Start-up phase assessment of a UASB-Septic tank system treating domestic septage

    International Nuclear Information System (INIS)

    Ali, M.; Al-Saed, R.; Mahmoud, N.

    2007-01-01

    About 65% of the annual domestic waste water in Palestine is currently collected in cesspits, where inadequate disposal might cause cumulative public health risks and annual environmental degradation. This research presents the preliminary results for the start-up period of a pilot-scale UASB-septic tank system treating domestic septage of Birzet town. Under different operational conditions, the performance of the pretreatment system for the removal of organic matter and nutrients was evaluated. Initial results showed that organic pollutants removal was mainly due to biophysical processes including sedimentation and microbial degradation. During start-up phase, the system attained removal efficiency for COD total of about 80% compared to removal for COD col, and COD dis of 71% and 43% respectively. Similarly, the continuous operation mode demonstrated that the system was quite effective in removing organic pollutants. Operational experience from the initial results revealed that seeding the USAB reactor with activated sludge during the start up period was not practical. Finally, the advantage of USAB-septic tank application appeared to be achievable if adequate system operation and control over a long monitoring period were maintained. (author)

  9. Pulse counting period meter output during startup transients

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1962-12-01

    The time response of a period meter whose input signal comes from a pulse counting channel may be calculated using a Ferranti Mercury autocode programme details of which are given. The period meter considered is the type for which the logarithmic characteristic is approximated by several diode pump circuits. The input excitation is a terminated ramp of reactivity. Other reactivity inputs may be treated. In particular the step change of reactivity may be used as the input excitation. Allowance is made for the effective time constants of the diode pump circuits and the period meter. The programme may be used for instrument assessment and for safety and operations studies on reactors which use this type of period meter. An example of the use of the programme is given. (author)

  10. The Alternative Design Features for Safety Enhancement in Shutdown Operation

    International Nuclear Information System (INIS)

    Oh, Hae Cheol; Kim, Myung Ki; Chung, Bag Soon; Seo, Mi Ro

    2009-01-01

    PSA can be used to confirm that the new plant design is complied with the applicable safety goals, and to select among the alternate design options. A shutdown PSA provides insight for outage planning schedule, outage management practices, and design modifications. Considering the results of both LPSD PSA studies and operating experiences for low power and shutdown, the improvements can be proposed to reduce the high risk contribution. The improvements/enhancements during shutdown operation may be divided into categories such as hardware, administrative management, and operational procedure. This paper presents on an example how the risk related to an accidental situation can be reduced, focusing the hardware design changes for the newly designed NPPs

  11. Start-up of Rapsodie; Le demarrage de Rapsodie

    Energy Technology Data Exchange (ETDEWEB)

    Pontier, R [Commissariat a l' Energie Atomique, 13 - Cadarache (France). Centre d' Etudes Nucleaires

    1967-07-01

    After giving a general description of Rapsodie this report presents the conditions in which the start-up occurred and in which the tests were carried out. A chronological account is given of the operations and of the main events which occurred. The modifications made to the reactor during this period are described and a synthesis of the results obtained is presented. (author) [French] Apres avoir donne de RAPSODIE une description tres generale, ce rapport expose le cadre dans lequel ont ete effectues le demarrage et les essais de l'installation, fait un historique du deroulement des operations et des principaux evenements qui sont intervenus, indique les modifications apportees au reacteur au cours de cette periode et presente une synthese des resultats obtenus. (auteur)

  12. Evaluation of slow shutdown system flux detectors in Point Lepreau Generating Station - I: dynamic response characterization

    Energy Technology Data Exchange (ETDEWEB)

    Anghel, V.N.P. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Comeau, D. [New Brunswick Power Nuclear, Point Lepreau, New Brunswick (Canada); McKay, J.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Taylor, D. [New Brunswick Power Nuclear, Point Lepreau, New Brunswick (Canada)

    2009-07-01

    CANDU reactors are protected against reactor overpower by two independent shutdown systems: Shut Down System 1 and 2 (SDS1 and SDS2). At the Point Lepreau Generating Station (PLGS), the shutdown systems can be actuated by measurements of the neutron flux by Platinum-clad Inconel In-Core Flux Detectors (ICFDs). These detectors have a complex dynamic behaviour, characterized by 'prompt' and 'delayed' components with respect to immediate changes in the in-core neutron flux. The dynamic response components need to be determined accurately in order to evaluate the effectiveness of the detectors for actuating the shutdown systems. The amplitudes of the prompt and the delayed components of individual detectors were estimated over a period of several years by comparison of archived detector response data with the computed local neutron flux evolution for SDS1 and SDS2 reactor trips. This was achieved by custom-designed algorithms. The results of this analysis show that the dynamic response of the detectors changes with irradiation, with the SDS2 detectors having 'prompt' signal components that decreased significantly with irradiation. Some general conclusions about detector aging effects are also drawn. (author)

  13. Study of methodology for low power/shutdown fire PSA

    International Nuclear Information System (INIS)

    Yan Zhen; Li Zhaohua; Li Lin; Song Lei

    2014-01-01

    As a risk assessment technology based on probability, the fire PSA is accepted abroad by nuclear industry in its application in the risk assessment for nuclear power plants. Based on the industry experience, the fire-induced impact on the plant safety during low power and shutdown operation cannot be neglected, therefore fire PSA can be used to assess the corresponding fire risk. However, there is no corresponding domestic guidance/standard as well as accepted analysis methodology up to date. Through investigating the latest evolvement on fire PSA during low power and shutdown operation, and integrating its characteristic with the corresponding engineering experience, an engineering methodology to evaluate the fire risk during low power and shutdown operation for nuclear power plant is established in this paper. In addition, an analysis demonstration as an example is given. (authors)

  14. Fusion reactors: physics and technology. Annual progress report

    International Nuclear Information System (INIS)

    Conn, R.W.

    1983-08-01

    Fusion reactors are designed to operate at full power and generally at steady state. Yet experience shows the load variations, licensing constraints, and frequent sub-system failures often require a plant to operate at fractions of rated power. The aim of this study has been to assess the technology problems and design implications of startup and fractional power operation on fusion reactors. The focus of attention has been tandem mirror reactors (TMR) and we have concentrated on the plasma and blanket engineering for startup and fractional power operation. In this report, we first discuss overall problems of startup, shutdown and staged power operation and their influence on TMR design. We then present a detailed discussion of the plasma physics associated with TMR startup and various means of achieving staged power operation. We then turn to the issue of instrumentation and safety controls for fusion reactors. Finally we discuss the limits on transient power variations during startup and shutdown of Li 17 Pb 83 cooled blankets

  15. Surface-to-surface biofilm transfer: a quick and reliable startup strategy for mixed culture microbial fuel cells.

    Science.gov (United States)

    Vogl, Andreas; Bischof, Franz; Wichern, Marc

    2016-01-01

    The startup of microbial fuel cells (MFCs) is known to be prone to failure or result in erratic performance impeding the research. The aim of this study was to advise a quick launch strategy for laboratory-scale MFCs that ensures steady operation performance in a short period of time. Different startup strategies were investigated and compared with membraneless single chamber MFCs. A direct surface-to-surface biofilm transfer (BFT) in an operating MFC proved to be the most efficient method. It provided steady power densities of 163 ± 13 mWm(-2) 4 days after inoculation compared to 58 ± 15 mWm(-2) after 30 days following a conventional inoculation approach. The in situ BFT eliminates the need for microbial acclimation during startup and reduces performance fluctuations caused by shifts in microbial biodiversity. Anaerobic pretreatment of the substrate and addition of suspended enzymes from an operating MFC into the new MFC proved to have a beneficial effect on startup and subsequent operation. Polarization methods were applied to characterize the startup phase and the steady state operation in terms of power densities, internal resistance and power overshoot during biofilm maturation. Applying this method a well-working MFC can be multiplied into an array of identically performing MFCs.

  16. Updating of the program for simulation of Darlington shutdown and regulation systems

    International Nuclear Information System (INIS)

    1988-07-01

    This report describes the current status of the developments of a simulation of the Darlington Nuclear Generating Station shutdown and regulating systems, DARSIM done under contract to the Atomic Energy Control Board (AECB). The DARSIM program simulates the spatial neutron dynamics, the regulation of the reactor power, and shutdown system 1 and shutdown system 2 software. The DARSIM program operates in the interactive simulation program environment. DARSIM was installed on the APOLLO computer at the AECB and a version for an IBM-PC was also provided for the exclusive use of the AECB. Shutdown system software was updated to incorporate the latest revisions in the functional specifications. Additional developments have been provided to assist in the use and interpretation of the DARSIM results

  17. Start-up analysis of INET-5 MW district heating prototype reactor

    International Nuclear Information System (INIS)

    Li Tianshu

    1991-09-01

    The main features and thermohydraulic design parameters of the INET-5 MW reactor (INET: Institute of Nuclear Technology of Tsinghua University, Beijing) are presented. The start-up process and the effect of thermohydraulic instability on start-up process have been analyzed. The main obstacle of start-up process of INET-5 MW reactor is to pass the instability region from 1 atm to normal operation condition. For avoiding instability, the start-up process should be divided into two steps. The results of three different start-up proposals calculated by DACOL code are given and compared. The possibility of instabilities for each proposal has been checked. The checked results show that there is no instability during start-up of the three proposals. So, it is supposed that the INET-5 MW reactor can safely and stably reach the operation conditions. Finally, some conclusions about the effect of instability on start-up in boiling mode of INET-5MW reactor are given

  18. Impact of entrepreneurship policies on opportunity to startup

    Directory of Open Access Journals (Sweden)

    Ali Davari

    2017-09-01

    Full Text Available During the previous decades, policy makers have formulated policies for developing entrepreneurship in different countries in order to decrease unemployment and poverty toward sustainable development. Some of these policies include encouraging people to be an entrepreneur, opportunity creation, educating new skills to entrepreneurs and so on. In recent years an appropriate context has been formed for entrepreneurship development in Iran and some programs have been executed. Therefore, formulating appropriate frameworks to guide Iranian government in this way is a necessity. This paper evaluates the impact of entrepreneurship policies on opportunity to startup in Iran. The results of path analysis indicate that supportive financial and non-financial actions influence positively on opportunity to startup. In addition, education and culture also influence positively on opportunity to startup. Finally, legislation also positively influences on opportunity to startup.

  19. Backup passive reactivity shutdown systems

    International Nuclear Information System (INIS)

    Ashurko, Yu.M.; Kuznetsov, L.A.

    1996-01-01

    The paper reviews self-actuated shutdown systems (SASSs) for liquid metal-cooled fast reactors (LMFRs). Principles of operation are described, advantages and drawbacks analyzed, and prospects for application in advanced fast reactors examined. Ways to improve reactor self-protection via reactivity feedback amplification and related problems are discussed. (author). 9 refs, 12 figs

  20. Backup passive reactivity shutdown systems

    Energy Technology Data Exchange (ETDEWEB)

    Ashurko, Yu M; Kuznetsov, L A [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1996-12-01

    The paper reviews self-actuated shutdown systems (SASSs) for liquid metal-cooled fast reactors (LMFRs). Principles of operation are described, advantages and drawbacks analyzed, and prospects for application in advanced fast reactors examined. Ways to improve reactor self-protection via reactivity feedback amplification and related problems are discussed. (author). 9 refs, 12 figs.

  1. An analysis of the sliding pressure start-up of SCWR

    International Nuclear Information System (INIS)

    Wang, F.; Yang, J.; Li, H.; Zhang, Y.; Zhang, J.; Shan, J.; Gou, J.; Zhang, B.; Chen, C.

    2012-01-01

    In this paper, the preliminary sliding pressure start-up system and scheme of supercritical water-cooled reactor in CGNPC (CGN-SCWR) were proposed. Thermal-hydraulic behavior in start-up procedures was analyzed in detail by employing advanced reactor subchannel analysis software ATHAS. The maximum cladding temperature (MCT for short) and core power of fuel assembly during the whole start-up process were investigated comparatively. The results show that the recommended start-up scheme meets the design requirements from the perspective of thermal-hydraulic. (authors)

  2. Control device for start-up of reactor depressurization system

    International Nuclear Information System (INIS)

    Suzuki, Hiroshi; Saito, Minoru; Oda, Shingo; Miura, Satoshi; Hashimoto, Koji; Tate, Hitoshi; Fujii, Kazunobu

    1998-01-01

    The present invention concerns are emergency reactor core cooling system (ECCS) of a BWR type reactor and provides a control device for start-up of an automatic depressurization system. Namely, the device has an object of preventing erroneous opening of a main steam escape safety value when testing a start-up signal circuit of an automatic depressurization system for testing the automatic depressurization system. A start-up signal circuit receives both signals of a reactor container pressure high signal and a reactor pressure vessel water level low signal and outputs an automatic start-up signal for compulsorily opening a main steam escape safety valve automatically. A test switch having a self-holding circuit is disposed to a central control chamber. A test signal circuit is disposed for preventing transfer of an erroneous start-up signal to the main steam escape safety valve due to a simulation signal during output test signals by the test switch. (I.S.)

  3. Risk impact of BWR technical specifications requirements during shutdown

    International Nuclear Information System (INIS)

    Staple, B.D.; Kirk, H.K.; Yakle, J.

    1994-10-01

    This report presents an application of probabilistic models and risk based criteria for determining the risk impact of the Limiting Conditions of Operations (LCOs) in the Technical Specifications (TSs) of a boiling water reactor during shutdown. This analysis studied the risk impact of the current requirements of Allowed Outage Times (AOTs) and Surveillance Test Intervals (STIs) in eight Plant Operational States (POSs) which encompass power operations, shutdown, and refueling. This report also discusses insights concerning TS action statements

  4. Loss-of-benefits analysis for nuclear power plant shutdowns: methodology and illustrative case study

    International Nuclear Information System (INIS)

    Peerenboom, J.P.; Buehring, W.A.; Guziel, K.A.

    1983-11-01

    A framework for loss-of-benefits analysis and a taxomony for identifying and categorizing the effects of nuclear power plant shutdowns or accidents are presented. The framework consists of three fundamental steps: (1) characterizing the shutdown; (2) identifying benefits lost as a result of the shutdown; and (3) quantifying effects. A decision analysis approach to regulatory decision making is presented that explicitly considers the loss of benefits. A case study of a hypothetical reactor shutdown illustrates one key loss of benefits: net replacement energy costs (i.e., change in production costs). Sensitivity studies investigate the responsiveness of case study results to changes in nuclear capacity factor, load growth, fuel price escalation, and discount rate. The effects of multiple reactor shutdowns on production costs are also described

  5. Effect of dc-power-system reliability on reactor-shutdown cooling

    International Nuclear Information System (INIS)

    Kolaczkowski, A.M.; Baranowsky, P.W.; Hickman, J.W.

    1981-01-01

    The DC power systems in a nuclear power plant provide control and motive power to valves, instrumentation, emergency diesel generators, and many other components and systems during all phases of plant operation including abnormal shutdowns and accident situations. A specific area of concern is the adequacy of the minimum design requirements for DC power systems, particularly with regard to multiple and common cause failures. This concern relates to the application of the single failure criterion for assuring a reliable DC power supply which may be required for the functionability of shutdown cooling systems. The results are presented of a reliability based study performed to assess the adequacy of DC power supply design requirements for currently operating light water reactors with particular attention to shutdown cooling requirements

  6. Post Fire Safe Shutdown Analysis Using a Fault Tree Logic Model

    International Nuclear Information System (INIS)

    Yim, Hyun Tae; Park, Jun Hyun

    2005-01-01

    Every nuclear power plant should have its own fire hazard analysis including the fire safe shutdown analysis. A safe shutdown (SSD) analysis is performed to demonstrate the capability of the plant to safely shut down for a fire in any given area. The basic assumption is that there will be fire damage to all cables and equipment located within a common fire area. When evaluating the SSD capabilities of the plant, based on a review of the systems, equipment and cables within each fire area, it should be determined which shutdown paths are either unaffected or least impacted by a postulated fire within the fire area. Instead of seeking a success path for safe shutdown given all cables and equipment damaged by a fire, there can be an alternative approach to determine the SSD capability: fault tree analysis. This paper introduces the methodology for fire SSD analysis using a fault tree logic model

  7. Decision Enhancement Services for Small and Medium Enterprise Start-Ups in Uganda

    NARCIS (Netherlands)

    Sol, H G; Basaza, Habinka; Sprague, Ralph H.

    2012-01-01

    While start-up firms create a substantial economic impact on most economies, the failure rate of start-up firms seems to remain high due to inadequate agile decision services. Deciding to start-up mining Small and Medium Enterprises (SME) is a challenging task in Uganda. Research on SME start-up

  8. Automated start-up of EBR-II

    International Nuclear Information System (INIS)

    Kisner, R.A.

    1989-01-01

    Oak Ridge National Laboratory (ORNL) and Argonne National Laboratory (ANL) are undertaking a joint project to develop control philosophies, strategies, and algorithms for computer control of the start-up mode of the Experimental Breeder Reactor II (EBR-II). The major objective of this project is to show that advanced liquid-metal reactor (LMR) plants can be operated from low power to full power using computer control. Development of an automated control system with this objective in view will help resolve specific issues and provide proof through demonstration that automatic control for plant start-up is feasible. This paper describes the approach that will be used to develop such a system and some of the features it is expected to have. Structured, rule-based methods, which will provide start-up capability from a variety of initial plant conditions and degrees of equipment operability, will be used for accomplishing mode changes during plant start-up. Several innovative features will be incorporated such as signal, command, and strategy validation to maximize reliability, flexibility to accommodate a wide range of plant conditions, and overall utility. Continuous control design will utilize figures of merit to evaluate how well the controller meets the mission requirements. The operator interface will have unique ''look ahead'' features to let the operator see what will happen next. 15 refs., 7 figs., 1 tab

  9. Strategies, Uncertainty and Performance of Small Business Startups

    NARCIS (Netherlands)

    A.M. van Gelderen (Marco); M. Frese (Michael); A.R. Thurik (Roy)

    2000-01-01

    textabstractPersonal strategies of owners/founders of small business startups are related to performance and to environmental uncertainty. This is done using a longitudinal data set of some 50 Dutch startups. The results suggest a dynamic process between strategy and performance. A discrimination is

  10. TIBER engineering test reactor (ETR) startup scenarios

    International Nuclear Information System (INIS)

    Blackfield, D.T.; Perkins, L.J.

    1987-01-01

    A time-dependent Tokamak Systems Code (TTSC) has been developed and used to examine various inductively driven startup scenarios for the TIBER reactor. Radially averaged particle and energy balance equations are solved. In addition, time varying currents in the PF and OH coils are determined from MHD equilibrium and volt-seconds considerations. Less than 20 MW of auxiliary power deposited in the electrons is required to obtain steady-state operations. For this scenario, less than 10% of the total volt-seconds capability is consumed during startup and the currents in the PF and OH coils do not appear to exceed stress limits. For every volt-second saved during startup, the burn time can be extended 14 seconds. 4 refs., 6 figs., 3 tabs

  11. Reliability of Offshore Wind Turbine Drivetrains based on Measured Shut-down Events

    DEFF Research Database (Denmark)

    Natarajan, Anand; Buhl, Thomas

    2015-01-01

    by initiating blade pitching to feather and also sometimes using the generator torqueas a brake mechanism. The shutdowns due to wind speed variation nearcut-out are predicted using an Inverse First Order Reliability Model(IFORM) whereby an expected annual frequency of normal shutdownsat cut-out is put forth...... normal operation and with shutdowns. The maximum coefficient of variation (CoV) due to varying wind conditions was found on the low speed shaft torsion, but the shutdowns by themselves were not seento significantly change the fatigue loads....

  12. Nuclear plant startup support problems experienced by B and W

    International Nuclear Information System (INIS)

    Spangler, W.H.; Phinney, J.D.

    1976-01-01

    There have now been enough nuclear power plants brought on line for the industry to recognize some of the problems that will occur during startup. Schedules are not being met; startup costs to both the utilities and the suppliers are excessive and unpredictable, and in some cases reliability has suffered. Manpower planning is difficult at best. Earlier and more accurate scheduling and planning are the most significant candidates for improvement. Greater attention to the startup organization and how it is to function is also a key. The organization should probably be designed with the specific startup task in mind

  13. Analysis of solutions for passively activated safety shutdown devices for SFR

    International Nuclear Information System (INIS)

    Burgazzi, Luciano

    2013-01-01

    Highlights: • Innovative systems for emergency shut down of fast reactors are proposed. • The concepts of inherent and passive safety are put forward. • The relative analysis in terms of safety and reliability is presented. • A comparative assessment among the concepts is performed. • Path forward is tracked. -- Abstract: In order to enhance the inherent safety of fast reactors, innovative reactivity control systems have been proposed for intrinsic ultimate shut-down instead of conventional scram rods, to cope with the potential consequences of severe unprotected transient accidents, such as an energetic core disruptive accident, as in case of sodium fast reactors. The passive shut-down systems are designed to shut-down system only by inherent passive reactivity feedback mechanism, under unprotected accident conditions, implying failure of reactor protection system. They are conceived to be self-actuated without any signal elaboration, since the actuation of the system is triggered by the effects induced by the transient like material dilatation, in case of overheating of the coolant for instance, according to fast reactor design to meet the safety requirements. This article looks at different special shutdown systems specifically engineered for prevention of severe accidents, to be implemented on fast reactors, with main focus on the investigation of the performance of the self-actuated shutdown systems in sodium fast reactors

  14. Intellectual property and financing strategies for technology startups

    CERN Document Server

    Halt, Jr , Gerald B; Stiles, Amber R; Fesnak, Robert

    2017-01-01

    This book offers a comprehensive, easy to understand guide for startup entities and developing companies, providing insight on the various sources of funding that are available, how these funding sources are useful at each stage of a company’s development, and offers a comprehensive intellectual property strategy that parallels each stage of development. The IP strategies offered in this book take into consideration the goals that most startups and companies have at each stage of development, as well as the limitations that exist at each stage (i.e., limited available resources earmarked for intellectual property asset development), and provides solutions that startups and companies can implement to maximize their return on intellectual property investments. This book also includes a number of descriptive examples, case studies and scenarios to illustrate the topics discussed, and is intended for use by startups and companies across all industries. Readers will garner an appreciation for the value that inte...

  15. Nuclear reactor shutdown system

    International Nuclear Information System (INIS)

    Mangus, J.D.; Cooper, M.H.

    1982-01-01

    An improved nuclear reactor shutdown system is described comprising a temperature sensitive device connected to control the electric power supply to a magnetic latch holding a body of a neutron absorbing material. The temperature sensitive device is exposed to the reactor coolant so that when the reactor coolant temperature rises above a specific level, the temperature sensitive device will cause deenergization of the magnetic latch to allow the body of neutron absorbing material to enter the reactor core. (author)

  16. Software development methodologies and practices in startups:systematic literature review

    OpenAIRE

    Tegegne, E. (Esubalew)

    2018-01-01

    Abstract Startups are newly created companies with little or no operating history and with limited resources and markets. Software startup are aiming to develop cutting edge software products under highly uncertain conditions, overcoming fast-growing markets under multiple influences. The significance of startups for economic development is growing in software business due to their ability to quickly create innovative techn...

  17. Investigation of cool down processes in a NPP turbine of the K-1000-60/1500 type

    International Nuclear Information System (INIS)

    Pereverzev, D.A.; Lebedev, A.G.; Palej, V.A.

    1985-01-01

    Methods of mathematical simulation were used to investigate cooling-off dynamics of separate NPP turbine parts of the K-1000-60/1500 type during shutdowns of different duration. Investigations indicated that a flange section of horizontal external casing joint in the steam inlet zone of the intermediate pressure casing is a main place limiting duration of turbine starting regime. When strengthening thermal protection of branch pipes, turbine start-up time (after shutdown during 72-168 h) can be reduced by 0.25-0.3 h; if also pick-ups are isolated than reduction of start-up duration will constitute 0.5-0.7 h. During shutdowns of shorter duration all critical assemblies will not limit in practice time of starting regime

  18. Internetové start-up projekty a jejich rizika

    OpenAIRE

    Sládek, Pavel

    2014-01-01

    The goal of this thesis is to analyse the field of the Internet startups and to find out what trends and risks are associated with their development and launching. The first chapter of this thesis summarizes the main changes in recent years and the methodologies that are the most often used in developing of startups. The work also reflects a problem connected with financing, such as investor interest in emerging projects. Then there is explained how startup investing works and what opportunit...

  19. Product innovation and commercialization in lean global start-ups

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager; Zijdemans, Erik

    2015-01-01

    The paper examines the distinctive characteristics of product innovation and commercialization in Lean Global Start-up (LGS) – new technology firms which have adopted a lean and global path from or near to their inception. It suggests an uncertainty vs risk framework which allows integrating two...... research streams – Born Global (BG) firms and lean start-ups. In addition to its integrative theoretical value, the paper offers insights for lean start-up managers dealing with the challenges of a global start....

  20. Automatic start-up system of nuclear reactor based on sequence control technology

    International Nuclear Information System (INIS)

    Zhang Yao; Zhang Dafa; Peng Huaqing

    2009-01-01

    A conceptive design of an automatic start-up system based on the sequence control for the nuclear reactors is given in this paper, so as to solve the problems during the start-up process, such as the long operation time, low automatic control level and high accident rate. The start-up process and its requirements are analyzed in detail at first. Then,the principle, the architecture, the key technologies of the automatic start-up system of nuclear reactors are designed and discussed. With the designed system, the automatic start-up of the nuclear reactor can be realized,the work load of the operator can be reduced,and the safety and efficiency of the nuclear power plant during its start-up can be improved. (authors)

  1. BWR shutdown analyzer using artificial intelligence (AI) techniques

    International Nuclear Information System (INIS)

    Cain, D.G.

    1986-01-01

    A prototype alarm system for detecting abnormal reactor shutdowns based on artificial intelligence technology is described. The system incorporates knowledge about Boiling Water Reactor (BWR) plant design and component behavior, as well as knowledge required to distinguish normal, abnormal, and ATWS accident conditions. The system was developed using a software tool environment for creating knowledge-based applications on a LISP machine. To facilitate prototype implementation and evaluation, a casual simulation of BWR shutdown sequences was developed and interfaced with the alarm system. An intelligent graphics interface for execution and control is described. System performance considerations and general observations relating to artificial intelligence application to nuclear power plant problems are provided

  2. Shortening start-up and an extension of the power unit load range

    Directory of Open Access Journals (Sweden)

    Taler Jan

    2017-01-01

    Full Text Available A power plant with additional water pressure tanks was proposed. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters was determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the off-peak night hours, water heated to the nominal temperature in low-pressure regenerative heaters is directed from the feed water tank to pressure tanks. The water accumulated during the night is used to feed the boiler during the period of peak demand for electricity. Pressure accumulators are proposed to be used for the rapid start-up of the boiler from a cold state. The evaporator of the boiler is filled at the beginning of start-up with hot water from the accumulators. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. The tanks may also be used to ensure a sudden increase in the electric power of the unit that is operating in the automatic system of frequency and power control (in Polish: ARCM.

  3. Probabilities of inherent shutdown of unprotected events in innovative liquid metal reactors

    International Nuclear Information System (INIS)

    Mueller, C.J.; Wade, D.C.

    1988-01-01

    The uncertainty in predicting the effectiveness of inherent shutdown in innovative liquid metal cooled reactors with metallic fuel results from three broad contributing areas of uncertainty: (1) the inability to exactly predict the frequency of ATWS events with potential to challenge the safety systems and require inherent shutdown; (2) the approximation of representing all such events by a selected set of ''generic scenarios''; and (3) the inability to exactly calculate the core response to the selected generic scenarios. This paper discusses the work being done to address each of these contributing areas, identifies the design and research approaches being used at Argonne National Laboratory to reducing the key contributions to uncertainties in inherent shutdown, and presents results. The conditional probabilities (given ATWS initiation) of achieving temperatures capable of defeating inherent shutdown are shown to range from /approximately/0.1% to negligible for current designs

  4. Start-up of NPP Krsko; Pokusno obratovanje NE Krsko

    Energy Technology Data Exchange (ETDEWEB)

    Spiler, J; Aralica, J [Nuklearna elektrana Krsko, Krsko (Yugoslavia)

    1984-07-01

    The report describes a review of start-up program and its realisation. There are also described some more significant start-up results with their evaluation. The most significant operation criteria are compared between NPP Krsko and other similar plants in the world. The comparison shows that after the first contractors and operation personnel efforts have been accomplished, our first nuclear power plant is a safe and reliable source of electric power. At the end there are listed NPP Krsko start-up recommendations and experience. (author)

  5. The Bulgaria before shut-down of next two blocks

    International Nuclear Information System (INIS)

    Dobak, D.

    2005-01-01

    The Ministry of Trade and Industry of United Kingdom in the frame of realization of programmes for the Middle and East Europe in the area of nuclear energetics during October 5 - 7, 2005 in Kozloduj has organized the Second International Conference on the theme 'Liquidation, social and economic changes'. In this paper author informs about Kozloduj NPP and plans for shut-down of this NPP as well as consequences of the shut-down. One of them the increase of unemployment and social impact for this region are presented

  6. Primary shutdown system monitoring unit for nuclear power plants

    International Nuclear Information System (INIS)

    Khan, Tahir Kamal; Balasubramanian, R.; Agilandaeswari, K.

    2013-01-01

    Shut off rods made up of neutron absorbing material are used as Primary Shutdown System. To reduce the power of the reactor under certain abnormal operating conditions, these rods must go down into the core within a specified time. Any malfunctioning in the movement of rods cannot be tolerated and Secondary Shutdown System (SSS) must be actuated within stipulated time to reduce the reactor power. A special safety critical, hardwired electronics unit has been designed to detect failure of PSS Shut off rods movements and generate trip signals for initiating SSS. (author)

  7. On line test of trip channels and actuators in primary shutdown system for RAPP-3,4/KAIGA-1,2 reactors

    International Nuclear Information System (INIS)

    Pramanik, M.; Gupta, P.K.; Ravi Prakash

    1997-01-01

    Several types of system design and logic arrangements have been used for reactor shutdown systems to avoid the possibility that a single failure within the trip channels/shutdown system actuators can prevent a shutdown system actuation. The trip channels and the logic arrangements associated with the shutdown systems use redundancy to allow them to continue to operate successfully even after having a certain number of failures. A periodic test is thus needed to detect and repair/replace failed elements to prevent accumulation and eventual system failure. The test must be capable of detecting the first failure. The design initiates shutdown system actuation by deenergising the logic relays and turning off the power to the final electrical actuators. Thus, the systems are fail safe with respect to loss of electrical power to the instruments, logic channels and the actuators. Several system/logic arrangements are used to reduce the chances of spurious actuation caused by the loss of a single power supply and other single failures. In general, the systems use coincidence of instrument channel trips and have separate power supplies for the individual instrument channel and dual power supplies where a single final control element is used. These features also permit on line test of instrument channels and logic train. On line test detects component failures not found by other means. The test determines whether gross failure has occurred rather than perform a calibration. As far as practicable the whole channel from sensors to logic and final control element is to be tested. (author)

  8. Dynamics and Control During Start-Up of Energy Integrated Distillation Column

    DEFF Research Database (Denmark)

    of the inherent effects of process integration upon a start-up procedure. In particular the effect of energy recycle upon the possible start-up sequence, and the effect of using an actuator for control purposes, i.e. the heat pump, which in itself requires significant start-up time. The experimental application...

  9. Effect of non-condensable gas on startup of a loop thermosyphon

    International Nuclear Information System (INIS)

    He, Jiang; Lin, Guiping; Bai, Lizhan; Miao, Jianyin; Zhang, Hongxing; Wang, Lu

    2013-01-01

    Non-condensable gas (NCG) generated inside two-phase heat transfer devices can adversely affect the thermal performance and limit the lifetime of such devices. In this work, experimental investigation of the effect of NCG on the startup of an ammonia-stainless steel loop thermosyphon was conducted. In the experiment, nitrogen was injected into the loop thermosyphon as NCG. The effect of NCG inventory on the startup behavior was investigated by adjusting the injected amount of nitrogen. The experimental results reveal that NCG prolongs the startup time and increases the startup liquid superheat and temperature overshoot; the more NCG exists in the loop thermosyphon, the higher the liquid superheat and temperature overshoot. When NCG is present in the system, boiling usually occurs in the evaporator before startup, but it does not mean the system will start up instantly, which differs from the conditions without NCG. Under all the conditions, increasing the heat load can effectively shorten the startup time but leads to a large temperature overshoot; forced convection cooling of the condenser has almost no effect on shortening the startup time especially for large NCG inventory situations, but it can effectively limit the temperature overshoot. For large NCG inventory situations, the loop thermosyphon can start up at a small heat load (5 W) or even without a heat load when the condenser is cooled by forced convection of ethanol. No failed start-ups occurred during any of the tests. (authors)

  10. Startup analysis for a high temperature gas loaded heat pipe

    Science.gov (United States)

    Sockol, P. M.

    1973-01-01

    A model for the rapid startup of a high-temperature gas-loaded heat pipe is presented. A two-dimensional diffusion analysis is used to determine the rate of energy transport by the vapor between the hot and cold zones of the pipe. The vapor transport rate is then incorporated in a simple thermal model of the startup of a radiation-cooled heat pipe. Numerical results for an argon-lithium system show that radial diffusion to the cold wall can produce large vapor flow rates during a rapid startup. The results also show that startup is not initiated until the vapor pressure p sub v in the hot zone reaches a precise value proportional to the initial gas pressure p sub i. Through proper choice of p sub i, startup can be delayed until p sub v is large enough to support a heat-transfer rate sufficient to overcome a thermal load on the heat pipe.

  11. Cold start-up condition model for heat recovery steam generators

    International Nuclear Information System (INIS)

    Sindareh-Esfahani, Peyman; Habibi-Siyahposh, Ehsan; Saffar-Avval, Majid; Ghaffari, Ali; Bakhtiari-Nejad, Firooz

    2014-01-01

    A dynamic modeling of Heat Recovery Steam Generator (HRSG) during cold start-up operation in Combined Cycle Power Plant (CCPP) is introduced. In order to characterize the essential dynamic behavior of the HRSG during cold start-up; Dynamic equations of all HRSG's components are developed based on energy and mass balances. To describe precisely the operation of HRSG; a method based on nonlinear estimated functions for thermodynamic properties is applied to estimate the model parameters. Model parameters are evaluated by a designed algorithm based on Genetic Algorithm (GA). A wide set of experimental data is used to validate HRSG model during cold start-up operation. The simulation results show the reliability and validity of the developed model for cold start-up operation. - Highlights: •Presenting a mathematical model for HRSGs cold start-up based on energy and mass balances. •A designed parameter identification algorithm based on GA is presented. •Application of experimental data in order to model and validate simulation results

  12. Skill Heterogeneity in Startups and its Development over Time

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Müller, Bettina

    2015-01-01

    We study how startup teams are assembled in terms of team member human capital characteristics. To this end, we derive a statistically motivated benchmark for new venture team heterogeneity in terms of observed team member characteristics to generate stylized facts about team member diversity...... at startup and how it evolves as the new venture matures. We use the population of Danish startups that were established in 1998 and track them until 2001. Main findings are that teams are relatively more homogeneous at startup compared to our benchmark, indicating that difficulties associated with workforce...... heterogeneity (like affective conflict or coordination cost) as well as “homophily” (people’s inclination to bound with others with similar characteristics) may overweigh the benefits of heterogeneity. While workforce heterogeneity does increase over time, the increase is smaller compared to our benchmark...

  13. Rapid startup of thermophilic anaerobic digester to remove tetracycline and sulfonamides resistance genes from sewage sludge.

    Science.gov (United States)

    Xu, Rui; Yang, Zhao-Hui; Wang, Qing-Peng; Bai, Yang; Liu, Jian-Bo; Zheng, Yue; Zhang, Yan-Ru; Xiong, Wei-Ping; Ahmad, Kito; Fan, Chang-Zheng

    2018-01-15

    Spread of antibiotic resistance genes (ARGs) originating from sewage sludge is highlighted as an eminent health threat. This study established a thermophilic anaerobic digester using one-step startup strategy to quickly remove tetracycline and sulfonamides resistance genes from sewage sludge. At least 20days were saved in the startup period from mesophilic to thermophilic condition. Based on the results of 16S rDNA amplicons sequencing and predicted metagenomic method, the successful startup largely relied on the fast colonization of core thermophilic microbial population (e.g. Firmicutes, Proteobacteria, Actinobacteria). Microbial metabolic gene pathways for substrate degradation and methane production was also increased by one-step mode. In addition, real-time quantitative PCR approach revealed that most targeted tetracycline and sulfonamides resistance genes ARGs (sulI, tetA, tetO, tetX) were substantially removed during thermophilic digestion (removal efficiency>80%). Network analysis showed that the elimination of ARGs was attributed to the decline of their horizontal (intI1 item) and vertical (potential hosts) transfer-related elements under high-temperature. This research demonstrated that rapid startup thermophilic anaerobic digestion of wastewater solids would be a suitable technology for reducing quantities of various ARGs. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. 40 CFR 63.4371 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... meet the data acquisition and availability requirements of this subpart, used to sample, condition (if... limit, or operating limit, or work practice standard in this subpart during startup, shutdown, or... substrate. Startup, initial means the first time equipment is brought online in a facility. Surface...

  15. Multi-unit shutdown due to boiler feedwater chemical excursion

    International Nuclear Information System (INIS)

    Diebel, M.E.

    1991-01-01

    Ontario Hydro's Bruce Nuclear Generating Station 'B' consists of four 935 W CANDU units located on the east shore of Lake Huron in the province of Ontario, Canada. On July 25 and 26, 1989 three of the four operating units were shutdown due to boiler feedwater chemical excursions initiated by a process upset in the Water Treatment Plant that provides demineralized make-up water to all four units. The chemicals that escaped from an ion exchange vessel during a routine regeneration very quickly spread through the condensate make-up system and into the boiler feedwater systems. This resulted in boiler sulfate levels exceeding shutdown limits. A total of 260 GWH of electrical generation was unexpectedly made unavailable to the grid at a time of peak seasonal demand. This event exposed several unforeseen deficiencies and vulnerabilities in the automatic demineralized water make-up quality protection scheme, system designs, operating procedures and the ability of operating personnel to recognize and appropriately respond to such an event. The combination of these factors contributed towards turning a minor system upset into a major multi-unit shutdown. This paper provides the details of the actual event initiation in the Water Treatment Plant and describes the sequence of events that led to the eventual shutdown of three units and near shutdown of the fourth. The design inadequacies, procedural deficiencies and operating personnel responses and difficulties are described. The process of recovering from this event, the flushing out of system piping, boilers and the feedwater train is covered as well as our experiences with setting up supplemental demineralized water supplies including trucking in water and the use of rental trailer mounted demineralizing systems. System design, procedural and operational changes that have been made and that are still being worked on in response to this event are described. The latest evidence of the effect of this event on boiler tube

  16. University Knowledge Spillovers & Regional Start-up Rates

    DEFF Research Database (Denmark)

    Hellerstedt, Karin; Wennberg, Karl; Frederiksen, Lars

    2014-01-01

    how characteristics of the economic and political milieu within each region influence the ratio of firm births. We find that knowledge spillovers from universities and firm-based R&D strongly affect the start-up rates for both high-tech firms and knowledge-intensive services firms. Further, the start......This chapter investigates how regional start-up rates in the knowledge-intensive services and high-tech industries are influenced by knowledge spillovers from both universities and firm-based R&D activities. Integrating insights from economic geography and organizational ecology into the literature......-up rate of knowledge-intensive service firms is tied more strongly to the supply of university educated individuals and the political regulatory regime within the municipality than start-ups in high-tech industries. This suggests that knowledge-intensive service-start-ups are more susceptible to both...

  17. Optimized dispatch in a first-principles concentrating solar power production model

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Michael J.; Newman, Alexandra M.; Hamilton, William T.; Braun, Robert J.

    2017-10-01

    Concentrating solar power towers, which include a steam-Rankine cycle with molten salt thermal energy storage, is an emerging technology whose maximum effectiveness relies on an optimal operational and dispatch policy. Given parameters such as start-up and shut-down penalties, expected electricity price profiles, solar availability, and system interoperability requirements, this paper seeks a profit-maximizing solution that determines start-up and shut-down times for the power cycle and solar receiver, and the times at which to dispatch stored and instantaneous quantities of energy over a 48-h horizon at hourly fidelity. The mixed-integer linear program (MIP) is subject to constraints including: (i) minimum and maximum rates of start-up and shut-down, (ii) energy balance, including energetic state of the system as a whole and its components, (iii) logical rules governing the operational modes of the power cycle and solar receiver, and (iv) operational consistency between time periods. The novelty in this work lies in the successful integration of a dispatch optimization model into a detailed techno-economic analysis tool, specifically, the National Renewable Energy Laboratory's System Advisor Model (SAM). The MIP produces an optimized operating strategy, historically determined via a heuristic. Using several market electricity pricing profiles, we present comparative results for a system with and without dispatch optimization, indicating that dispatch optimization can improve plant profitability by 5-20% and thereby alter the economics of concentrating solar power technology. While we examine a molten salt power tower system, this analysis is equally applicable to the more mature concentrating solar parabolic trough system with thermal energy storage.

  18. Dynamics and Control During Start-up of Energy Integrated Distillation Column

    DEFF Research Database (Denmark)

    Eden, Mario Richard; Koggersbøl, Arne; Hallager, L.

    2000-01-01

    of the inherent effects of process integration upon a start-up procedure. In particular the effect of energy recycle upon the possible start-up sequence, and the effect of using an actuator f or control purposes, i.e. the heat pump, which in itself requires significant start-up time. The experimental application...

  19. 78 FR 73753 - Partnerships; Start-Up Expenditures; Organization and Syndication Fees

    Science.gov (United States)

    2013-12-09

    ... deduct start-up expenditures in the taxable year in which the active trade or business begins. The amount... begins. All start-up expenditures that relate to the active trade or business are considered in...(b) to amortize start-up expenditures for the taxable year in which the active trade or business to...

  20. Shutdown risk management applied at Philadelphia Electric Company

    International Nuclear Information System (INIS)

    Dagan, William J.; True, Douglas E.; Wilson, Thomas; Truax, William

    2004-01-01

    The development and implementation of an effective risk management program requires basic risk or safety knowledge and the conversion of such information into effective management tools. ERIN Engineering and Research, Inc., under contract to the Electric Power Research Institute, has developed an effective program. Outage Risk Assessment and Management (ORAM), to provide plant and management personnel with understandable results of shutdown risk studies. With this tool, the impact of plans and decision options can be readily determined and displayed for the decision maker. This paper describes these methods and their application to the Limerick Nuclear Station of Philadelphia Electric Company. It also sets forth a broader application of these methods to include support of management decisions at-power and following forced outages. The result is an integrated risk management framework which can allow management and technical personnel to utilize readily available and understandable risk insights to optimize each activity. This paper addresses the resolution of several key issues in detail: How was the ORAM risk management method employed to represent the existing plant shutdown procedures and policies? How did the ORAM risk management method enhance the decision-making ability of the outage management staff? How was the ORAM software efficiently integrated with the outage scheduling software? How is quantitative risk information generated and used for outage planning and control? The ORAM risk management philosophy utilizes a series of colors to depict various risk configurations. Each such configuration has associated with it clear guidance. By modifying the conditions existing in the plant it is possible to impact the type of risk being encountered as well as the guidance which is appropriate for that period. In addition, the duration of a particular configuration can be effectively managed to reduce the overall risk impact. These are achieved with minimal

  1. Probabilistic safety assessments of nuclear power plants for low power and shutdown modes

    International Nuclear Information System (INIS)

    2000-03-01

    Within the past several years the results of nuclear power plant operating experience and performance of probabilistic safety assessments (PSAs) for low power and shutdown operating modes have revealed that the risk from operating modes other than full power may contribute significantly to the overall risk from plant operations. These early results have led to an increased focus on safety during low power and shutdown operating modes and to an increased interest of many plant operators in performing shutdown and low power PSAs. This publication was developed to provide guidance and insights on the performance of PSA for shutdown and low power operating modes. The preparation of this publication was initiated in 1994. Two technical consultants meetings were conducted in 1994 and one in February 1999 in support of the development of this report

  2. Startup method for natural convection type nuclear reactor

    International Nuclear Information System (INIS)

    Utsuno, Hideaki.

    1993-01-01

    In a nuclear reactor started by natural convection, no sufficient stability margin can be ensured upon start up. Then, in the present invention, a deaerating operation is conducted before start-up of the reactor, then control rods are withdrawn after conducting the deaerating operation and temperature and pressure are raised by nuclear heating, to obtain a rated power. As a result, reactor power and subcooling at the inlet of the reactor core are within a range of lower than a geysering forming region, thereby enabling to prevent occurence of geysering inherent to the start-up of operation in a natural convection state, shorten the start-up time, as well as remove oxygen dissolved in coolants. (N.H.)

  3. Startup of a high-temperature reactor cooled and moderated by supercritical-pressure light water

    International Nuclear Information System (INIS)

    Yi, Tin Tin; Ishiwatari, Yuki; Koshizuka, Seiichi; Oka, Yoshiaki

    2003-01-01

    The startup schemes of high-temperature reactors cooled and moderated by supercritical pressure light water (SCLWR-H) with square lattice and descending flow type water rods are studied by thermal-hydraulic analysis. In this study, two kinds of startup systems are investigated. In the constant pressure startup system, the reactor starts at a supercritical pressure. A flash tank and pressure reducing valves are necessary. The flash tank is designed so that the moisture content in the steam is less than 0.1%. In sliding pressure startup system, the reactor starts at a subcritical pressure. A steam-water separator and a drain tank are required for two-phase flow at startup. The separator is designed by referring to the water separator used in supercritical fossil-fired power plants. The maximum cladding surface temperature during the power-raising phase of startup is restricted not to exceed the rated value of 620degC. The minimum feedwater flow rate is 25% for constant pressure startup and 35% for sliding pressure startup system. It is found that both constant pressure startup system and sliding pressure startup system are feasible in SCLWR-H from the thermal hydraulic point of view. The core outlet temperature as high as 500degC can be achieved in the present design of SCLWR-H. Since the feedwater flow rate of SCLWR-H (1190 kg/s) is lower than that of the previous SCR designs the weight of the component required for startup is reduced. The sliding pressure startup system is better than constant pressure startup system in order to reduce the required component weight (and hence material expenditure) and to simplify the startup plant system. (author)

  4. Optimal test intervals for shutdown systems for the Cernavoda nuclear power station

    International Nuclear Information System (INIS)

    Negut, Gh.; Laslau, F.

    1993-01-01

    Cernavoda nuclear power station required a complete PSA study. As a part of this study, an important goal to enhance the effectiveness of the plant operation is to establish optimal test intervals for the important engineering safety systems. The paper presents, briefly, the current methods to optimize the test intervals. For this reason it was used Vesely methods to establish optimal test intervals and Frantic code to survey the influence of the test intervals on system availability. The applications were done on the Shutdown System no. 1, a shutdown system provided whit solid rods and on Shutdown System no. 2 provided with injecting poison. The shutdown systems receive nine total independent scram signals that dictate the test interval. Fault trees for the both safety systems were developed. For the fault tree solutions an original code developed in our Institute was used. The results, intended to be implemented in the technical specifications for test and operation of Cernavoda NPS are presented

  5. The shutdown reactor: Optimizing spent fuel storage cost

    International Nuclear Information System (INIS)

    Pennington, C.W.

    1995-01-01

    Several studies have indicated that the most prudent way to store fuel at a shutdown reactor site safely and economically is through the use of a dry storage facility licensed under 10CFR72. While such storage is certainly safe, is it true that the dry ISFSI represents the safest and most economical approach for the utility? While no one is really able to answer that question definitely, as yet, Holtec has studied this issue for some time and believes that both an economic and safety case can be made for an optimization strategy that calls for the use of both wet and dry ISFSI storage of spent fuel at some plants. For the sake of brevity, this paper summarizes some of Holtec's findings with respect to the economics of maintaining some fuel in wet storage at a shutdown reactor. The safety issue, or more importantly the perception of safety of spent fuel in wet storage, still varies too much with the eye of the beholder, and until a more rigorous presentation of safety analyses can be made in a regulatory setting, it is not practically useful to argue about how many angels can sit on the head of a safety-related pin. Holtec is prepared to present such analyses, but this does not appear to be the proper venue. Thus, this paper simply looks at certain economic elements of a wet ISFSI at a shutdown reactor to make a prima facie case that wet storage has some attractiveness at a shutdown reactor and should not be rejected out of hand. Indeed, an optimization study at certain plants may well show the economic vitality of keeping some fuel in the pool and converting the NRC licensing coverage from 10CFR50 to 10CFR72. If the economics look attractive, then the safety issue may be confronted with a compelling interest

  6. Start-Up Funding Intentions Among Nascent Nonprofit Entrepreneurs: An Exploratory Investigation

    Directory of Open Access Journals (Sweden)

    Fredrik O. Andersson

    2018-04-01

    Full Text Available This paper explores the start-up funding intentions of nascent nonprofit entrepreneurs, i.e., individuals in the process of creating a new formal nonprofit organization. The main questions being examined are from which sources nascent nonprofit entrepreneurs anticipate to obtain start-up funding from, how much start-up funding nascent nonprofit entrepreneurs anticipate they will need to formally launch their new nonprofit, and if there are any differences in funding intentions among nascent nonprofit entrepreneurs with and without previous start-up experience. The results from a survey of 103 nascent nonprofit entrepreneurs in Kansas City are presented and contrasted with existing research on funding of new nonprofit organizations. The results show an apparent preference for start-up funding from philanthropic grants and private donations, along with personal contributions of the founder(s.

  7. Plasma startup patterns in tokamak reactors

    International Nuclear Information System (INIS)

    Maki, Koichi; Tone, Tatsuzo.

    1983-01-01

    Plasma startup patterns are studied from the viewpoint of net power loss represented by the total power loss less the α-particle heating power. The existence is shown of a critical temperature of plasma at which the net power loss becomes independent of plasma density. Observations are made which indicate that the net power loss decreases with lowering plasma density in the range below the critical temperature and vice versa, whether governed by empirical or trapped-ion scaling laws. A startup pattern is presented which minimizes the net power loss during startup, and which prescribes that: (1) The plasma density should be kept as low as possible until the plasma is heated up to the critical temperature; (2) thereafter, the plasma density should be increased to its steady state value while retaining the critical temperature; and (3) finally, with the density kept constant, the temperature should be further raised to its steady state value. The net power loss at critical temperature represents the lower limit of heating power required to bring the plasma to steady state in tokamak reactors. (author)

  8. Periodic safety analyses; Les essais periodiques

    Energy Technology Data Exchange (ETDEWEB)

    Gouffon, A; Zermizoglou, R

    1990-12-01

    The IAEA Safety Guide 50-SG-S8 devoted to 'Safety Aspects of Foundations of Nuclear Power Plants' indicates that operator of a NPP should establish a program for inspection of safe operation during construction, start-up and service life of the plant for obtaining data needed for estimating the life time of structures and components. At the same time the program should ensure that the safety margins are appropriate. Periodic safety analysis are an important part of the safety inspection program. Periodic safety reports is a method for testing the whole system or a part of the safety system following the precise criteria. Periodic safety analyses are not meant for qualification of the plant components. Separate analyses are devoted to: start-up, qualification of components and materials, and aging. All these analyses are described in this presentation. The last chapter describes the experience obtained for PWR-900 and PWR-1300 units from 1986-1989.

  9. Startup Report for Ground Water Extraction, Treatment, and Recharge System

    National Research Council Canada - National Science Library

    Lamb, Steve

    1997-01-01

    The document presents startup procedures, observations and measurements conducted during the startup of the Groundwater Extraction, Treatment and Recharge System, built for the 162nd Fighter Wing, Air...

  10. Investigation of the K-500-65/3000 turbine and its foundation defopmation

    International Nuclear Information System (INIS)

    Gluzshtejn, Yu.O.; Gurevich, G.I.; Zarkovskij, Yu.V.; Mikheev, Yu.I.; Ustavich, G.A.; Tyshchuk, O.L.; Cherepanov, D.A.; Chesheva, I.N.

    1984-01-01

    At the Leningrad NPP during the seren-year period four K-50a-65/3000 turbine and their foundation deformation measurements have been performed by means of a high accuracy geometric levelling. Determined are: settling values and values of residual deformations of the lower foundation plate, thermal deformations of the upper foundation structure under different turbine operation conditions, turbine shafting bearing shafting at the horizontal joint level; horizontal time required for shafting bearing stabilization upon shut-down and start-up of the turbine. Tne turbine foundation columns elongation has been determined with accuracy of 0.05-0.06 mm and 0.06-0.08 mm at the shut-down or operating turbine, respectively. For levelling a leveller has been applied, the accuracy of measurement of relative height of which is equal to 0.03 mm at the 6 m collimating ray length. The measurement accuracy is decreasing at the operating turbine up to 0.04-0.05 mm. As a result of measurements it has been revealed that relative bearing shifting occurs during the first 8-10 days after shut-down and 4-5 days after start-up and reach 2.5 and 2.0 mm, respectively. In addition, shafting bearing centers shifting has been determined at the operating and shut-down turbine. The conclusion is drawn that the number of problems of shafting bearing alignment of high power turbines arising during their mounting, operation and maintenance, one may succeed in solving by means of high accuracy geometric levelling

  11. MCR2S unstructured mesh capabilities for use in shutdown dose rate analysis

    International Nuclear Information System (INIS)

    Eade, T.; Stonell, D.; Turner, A.

    2015-01-01

    Highlights: • Advancements in shutdown dose rate calculations will be needed as fusion moves from experimental reactors to full scale demonstration reactors in order to ensure the safety of personnel. • The MCR2S shutdown dose rate tool has been modified to allow shutdown dose rates calculations using an unstructured mesh. • The unstructured mesh capability of MCR2S was used on three shutdown dose rate models, a simple sphere, the ITER computational benchmark and the DEMO computational benchmark. • The results showed a reasonable agreement between an unstructured mesh approach and the CSG approach and highlighted the need to carefully choose the unstructured mesh resolution. - Abstract: As nuclear fusion progresses towards a sustainable energy source and the power of tokamak devices increases, a greater understanding of the radiation fields will be required. As well as on-load radiation fields, off-load or shutdown radiation field are an important consideration for the safety and economic viability of a commercial fusion reactor. Previously codes such as MCR2S have been written in order to predict the shutdown dose rates within, and in regions surrounding, a fusion reactor. MCR2S utilises a constructive solid geometry (CSG) model and a superimposed structured mesh to calculate 3-D maps of the shutdown dose rate. A new approach to MCR2S calculations is proposed and implemented using a single unstructured mesh to replace both the CSG model and the superimposed structured mesh. This new MCR2S approach has been demonstrated on three models of increasing complexity. These models were: a sphere, the ITER computational shutdown dose rate benchmark and the DEMO computational shutdown dose rate benchmark. In each case the results were compared to MCR2S calculations performed using MCR2S with CSG geometry and a superimposed structured mesh. It was concluded that the results from the unstructured mesh implementation of MCR2S compared well to the CSG structured mesh

  12. 40 CFR 63.4581 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... total equipment that may be required to meet the data acquisition and availability requirements of this... standard in this subpart during startup, shutdown, or malfunction, regardless of whether or not such... de minimis manner. Responsible official means responsible official as defined in 40 CFR 70.2. Startup...

  13. 40 CFR 63.998 - Recordkeeping requirements.

    Science.gov (United States)

    2010-07-01

    ... and calculates the hourly averages through the use of a computerized data acquisition system. (iv) A... thereof), resulting in cessation of the emissions to which the monitoring applies; and (iii) Startups... section. (A) The daily average value during any startup, shutdown, or malfunction shall not be considered...

  14. 40 CFR 63.3176 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... monitoring system (CPMS) means the total equipment that may be required to meet the data acquisition and... this subpart during startup, shutdown, or malfunction, regardless of whether or not such failure is... area immediately preceding or immediately following the spray booth. Startup, initial means the first...

  15. On line testing of shutdown system

    International Nuclear Information System (INIS)

    Ramnath, S.; Swaminathan, P.; Sreenivasan, P.

    1997-01-01

    For ensuring high reliability and availability, safety related Instrumentation channels are triplicated. Solid state electronics can fail in safe or unsafe mode. Hence, it is necessary to supervise the safety related Instrumentation channels from sensor to final shutdown system. Microprocessor/ Microcontroller/ ASIC based online supervision systems are detailed in this paper. (author)

  16. 78 FR 38739 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

    Science.gov (United States)

    2013-06-27

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0299] Standard Format and Content for Post-Shutdown Decommissioning Activities Report AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide; issuance..., ``Standard Format and Content for Post-shutdown Decommissioning Activities Report.'' This guide describes a...

  17. The Lean and Global Start-up

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager

    For several decades researchers have studied start-up companies with a focus on international markets, suppliers and networks from their inception and on companies that are establishing new, agile business models. This has resulted in two streams of research: The Born Global and International New...... Ventures research and research with a focus on the Lean Start-up company. It is our intention in this paper to give a short presentation of the two research streams and show how they can be merged into one with a focus on newly established technology oriented firms that are lean and global from...

  18. Startup operation of Browns Ferry's 1152-MW nuclear units

    International Nuclear Information System (INIS)

    Calhoun, J.R.; Green, H.J.; Beers, R.B.

    1975-01-01

    An overview is presented of startup operation for the Browns Ferry-1 reactor, and comparisons are made with the startup of Browns Ferry-2. Included are comments on the selection of the BWR type steam supply system, reactor fueling, problems encountered, and plant availability

  19. Start-up and incremental practice expenses for behavior change interventions in primary care.

    Science.gov (United States)

    Dodoo, Martey S; Krist, Alex H; Cifuentes, Maribel; Green, Larry A

    2008-11-01

    If behavior-change services are to be offered routinely in primary care practices, providers must be appropriately compensated. Estimating what is spent by practices in providing such services is a critical component of establishing appropriate payment and was the objective of this study. In-practice expenditure data were collected for ten different interventions, using a standardized instrument in 29 practices nested in ten practice-based research networks across the U.S. during 2006-2007. The data were analyzed using standard templates to create credible estimates of the expenses incurred for both the start-up period and the implementation phase of the interventions. Average monthly start-up expenses were $1860 per practice (SE=$455). Most start-up expenditures were for staff training. Average monthly incremental costs were $58 ($15 for provision of direct care [SE=$5]; $43 in overhead [SE=$17]) per patient participant. The bulk of the intervention expenditures was spent on the recruitment and screening of patient participants. Primary care practices must spend money to address their patients' unhealthy behaviors--at least $1860 to initiate systematic approaches and $58 monthly per participating patient to implement the approaches routinely. Until primary care payment systems incorporate these expenses, it is unlikely that these services will be readily available.

  20. Selected safety-related occurrences reported in May and June 1977

    International Nuclear Information System (INIS)

    Casto, W.R.

    1977-01-01

    The following occurrences are reviewed because of their uniqueness and/or general interest: (1) short reactor periods have occurred at Quad Cities 1 during shutdown margin tests; (2) loss of instrument air caused damage to reactor coolant-pump seals at a pressurized-water reactor (PWR); (3) a power-distribution anomaly occurred because of a failure of burnable poison rods at St. Lucie 1; (4) short reactor periods have occurred at some boiling-water reactors (BWRs) during startups at peak xenon; and (5) surging in the feedwater flow caused pipe vibrations at Beaver Valley 1

  1. Agile metodologies use for software development in Slovenian start-ups

    OpenAIRE

    Kašnik, Matic

    2014-01-01

    The thesis presents and describes the use of agile methodologies which are being used by Slovenian tech start-up companies. It describes the basic features, advantages and disadvantages of various agile methodologies such as Scrum, extreme programming, lean start-up and method Kanban. We made a review of the most used agile methodologies in Slovenian technology start-up companies. In particular, we focus on variety of tools, technics and approaches used by the development teams and where do t...

  2. The Rationality and Irrationality of Financing Green Start-Ups

    Directory of Open Access Journals (Sweden)

    Linda Bergset

    2015-11-01

    Full Text Available Green start-ups contribute towards a transition to a more sustainable economy by developing sustainable and environmentally friendly innovation and bringing it to the market. Due to specific product/service characteristics, entrepreneurial motivation and company strategies that might differ from that of other start-ups, these companies might struggle even more than usual with access to finance in the early stages. This conceptual paper seeks to explain these challenges through the theoretical lenses of entrepreneurial finance and behavioural finance. While entrepreneurial finance theory contributes to a partial understanding of green start-up finance, behavioural finance is able to solve a remaining explanatory deficit produced by entrepreneurial finance theory. Although some behavioural finance theorists are suggesting that the current understanding of economic rationality underlying behavioural finance research is inadequate, most scholars have not yet challenged these assumptions, which constrict a comprehensive and realistic description of the reality of entrepreneurial finance in green start-ups. The aim of the paper is thus, first, to explore the specifics of entrepreneurial finance in green start-ups and, second, to demonstrate the need for a more up-to-date conception of rationality in behavioural finance theory in order to enable realistic empirical research in this field.

  3. Multi-Objective Optimization of Start-up Strategy for Pumped Storage Units

    Directory of Open Access Journals (Sweden)

    Jinjiao Hou

    2018-05-01

    Full Text Available This paper proposes a multi-objective optimization method for the start-up strategy of pumped storage units (PSU for the first time. In the multi-objective optimization method, the speed rise time and the overshoot during the process of the start-up are taken as the objectives. A precise simulation platform is built for simulating the transient process of start-up, and for calculating the objectives based on the process. The Multi-objective Particle Swarm Optimization algorithm (MOPSO is adopted to optimize the widely applied start-up strategies based on one-stage direct guide vane control (DGVC, and two-stage DGVC. Based on the Pareto Front obtained, a multi-objective decision-making method based on the relative objective proximity is used to sort the solutions in the Pareto Front. Start-up strategy optimization for a PSU of a pumped storage power station in Jiangxi Province in China is conducted in experiments. The results show that: (1 compared with the single objective optimization, the proposed multi-objective optimization of start-up strategy not only greatly shortens the speed rise time and the speed overshoot, but also makes the speed curve quickly stabilize; (2 multi-objective optimization of strategy based on two-stage DGVC achieves better solution for a quick and smooth start-up of PSU than that of the strategy based on one-stage DGVC.

  4. Start-up test of the prototype heavy water reactor 'FUGEN', (1)

    International Nuclear Information System (INIS)

    Ando, Hideki; Kawahara, Toshio

    1982-01-01

    The advanced thermal prototype reactor ''Fugen'' is a heavy water-moderated, boiling light water-cooled power reactor with electric output of 165 MW, which has been developed since 1966 as a national project. The start-up test was begun in March, 1978, being scheduled for about one year, and in March, 1979, it passed the final pre-use inspection and began the full scale operation. In this paper, the result of the start-up test of Fugen is reported. From the experience of the start-up test of Fugen, the following matters are important for the execution of start-up test. 1) Exact testing plan and work schedule, 2) the organization to perform the test, 3) the rapid evaluation of test results and the reflection to next testing plan, and 4) the reflection of test results to rated operation, regular inspection and so on. In the testing plan, the core characteristics peculiar to Fugen, and the features of heavy water-helium system, control system and other equipment were added to the contents of the start-up test of BWRs. The items of the start-up test were reactor physics test, plant equipment performance test, plant dynamic characteristic test, chemical and radiation measurement, and combined test. The organization to perform the start-up test, and the progress and the results of the test are reported. (Kako, I.)

  5. Start-Up Size Strategy and Risk Management: Impact on New Venture Performance

    OpenAIRE

    André van Stel; Andrew Burke; José Maria Millán; Concepcion Roman

    2013-01-01

    Start-up size is a key strategic decision for entrepreneurs. Should entrepreneurs start up close to minimum efficient scale or should they take less risks and start-up on a smaller scale? Previously, this strategic decision appeared to be one of simply making a choice between a higher risk/reward larger start-up versus a lower risk/reward smaller scale start-up. However, recent research on the relationship between risk management and performance (Burke, 2009) indicates that in situations of g...

  6. CV activities on the LHC complex during the long shutdown

    CERN Document Server

    Deleval, S; Body, Y; Obrecht, M; Moccia, S; Peon, G

    2011-01-01

    The presentation gives an overview of the major projects and work foreseen to be performed during next long shutdown on cooling and ventilation plants. Several projects are needed following the experience of the last years when LHC was running, in particular the modifications in the water cooling circuits presently in overflow. Some other projects are linked to the CV consolidation plan. Finally, most of the work shall be done to respond to additional requests: SR buildings air conditioning, the need to be able to clean and maintain the LHC cooling towers without a complete stop of cooling circuits, the upgrade of the air conditioning of the CCC rack room cooling etc. For all these activities, the author will detail constraints and the impact on the schedule and on the operation of the plants that will however need to run for most of the shutdown duration. The consequence of postponing the long shutdown from 2012 to 2013 will be also covered.

  7. Producing an Assistant Guide for Haaga-Helia StartUp School

    OpenAIRE

    Averina, Maria

    2016-01-01

    This product-oriented thesis was commissioned by the StartUp School (SUS), a program of Haaga-Helia University of Applied Sciences that supports Haaga-Helia students to become entrepreneurs. The StartUp School offers Haaga-Helia students a six-month assistant trainee position. Consequently, every half a year there is a new assistant at the StartUp School. The commissioning party was lacking an essential tool to introduce work tasks to new assistant interns. The objective of the thesis was...

  8. TRACG-CFD analysis of ESBWR reactor water cleanup shutdown cooling system mixing coefficient

    International Nuclear Information System (INIS)

    Gallardo, J.; Marquino, W.; Mistreanu, A.; Yang, J.

    2015-09-01

    The ESBWR is a 1520 nominal [M We] Generation III+ natural circulation boiling water reactor designed to high levels of safety utilizing features that have been successfully used before in operating BWRs, as well as standard features common to A BWR. In September of 2014, the US NRC has certified the ESBWR design for use in the USA. The RWCU/Sdc is an auxiliary system for the ESBWR nuclear island. Basic functions it performs include purifying the reactor coolant during normal operation and shutdown and providing shutdown cooling and cooldown to cold shutdown conditions. The performance of the RWCU system during shutdown cooling is directly related to the temperature of the water removed through the outlets, which is coupled with the vessel and F W temperatures through a thermal mixing coefficient. The complex three-dimensional (3-D) geometry of the BWR downcomer and lower plenum has a great impact on the flow mixing. Only a fine mesh technique like CFD can predict the 3-D temperature distribution in the RPV during shutdown and provide the RWCU/Sdc system inlet temperature. Plant shutdown is an unsteady event by nature and was modeled as a succession of CFD steady-state simulations. It is required to establish the mixing coefficient (which is a function of the heat balance and the core flow) during the operation of the RWCU system in the multiple shutdown cooling modes, and therefore a range of core flows needs to be estimated using quasi steady states obtained with TRACG. The lower end of that range is obtained from a system with minimal power decay heat and core flow; while the higher end corresponds to the power at the beginning of RWCU/Sdc operation when the cooldown is transferred to the RWCU/Sdc after the initial depressurization via the turbine bypass valves. Because the ESBWR RWCU/Sdc return and suction designs provide good mixing, the uniform mixing energy balance was found to be an adequate alternative for deriving the mixing coefficient. The CFD mass flow

  9. TRACG-CFD analysis of ESBWR reactor water cleanup shutdown cooling system mixing coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, J. [UNAM, Facultad de Ingenieria, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Marquino, W.; Mistreanu, A.; Yang, J., E-mail: euqrop@hotmail.com [General Electric Hitachi Nuclear Energy, Wilmington, 28401 North Carolina (United States)

    2015-09-15

    The ESBWR is a 1520 nominal [M We] Generation III+ natural circulation boiling water reactor designed to high levels of safety utilizing features that have been successfully used before in operating BWRs, as well as standard features common to A BWR. In September of 2014, the US NRC has certified the ESBWR design for use in the USA. The RWCU/Sdc is an auxiliary system for the ESBWR nuclear island. Basic functions it performs include purifying the reactor coolant during normal operation and shutdown and providing shutdown cooling and cooldown to cold shutdown conditions. The performance of the RWCU system during shutdown cooling is directly related to the temperature of the water removed through the outlets, which is coupled with the vessel and F W temperatures through a thermal mixing coefficient. The complex three-dimensional (3-D) geometry of the BWR downcomer and lower plenum has a great impact on the flow mixing. Only a fine mesh technique like CFD can predict the 3-D temperature distribution in the RPV during shutdown and provide the RWCU/Sdc system inlet temperature. Plant shutdown is an unsteady event by nature and was modeled as a succession of CFD steady-state simulations. It is required to establish the mixing coefficient (which is a function of the heat balance and the core flow) during the operation of the RWCU system in the multiple shutdown cooling modes, and therefore a range of core flows needs to be estimated using quasi steady states obtained with TRACG. The lower end of that range is obtained from a system with minimal power decay heat and core flow; while the higher end corresponds to the power at the beginning of RWCU/Sdc operation when the cooldown is transferred to the RWCU/Sdc after the initial depressurization via the turbine bypass valves. Because the ESBWR RWCU/Sdc return and suction designs provide good mixing, the uniform mixing energy balance was found to be an adequate alternative for deriving the mixing coefficient. The CFD mass flow

  10. 40 CFR 63.4181 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... may be required to meet the data acquisition and availability requirements of this subpart used to... subpart during startup, shutdown, or malfunction regardless of whether or not such failure is permitted by.... Responsible official means responsible official as defined in 40 CFR 70.2. Startup, initial means the first...

  11. 40 CFR 63.4981 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... monitoring system (CPMS) means the total equipment that may be required to meet the data acquisition and... limit, or work practice standard in this subpart during startup, shutdown, or malfunction, regardless of... CFR 70.2. Startup, initial means the first time equipment is brought online in a facility. Surface...

  12. Republic of Korea: Design Study for Passive Shutdown System of the PGSFR

    International Nuclear Information System (INIS)

    Lee, J.H.

    2015-01-01

    There have been no experiences of implementing a passive shutdown system in operating or operated SFRs around the world. However, new SFRs are considered to adopt a self-actuated shutdown system (SASS) in the future to provide an alternate means of passively shutting down the reactor. The Prototype Gen-IV SFR (PGSFR) developed by KAERI also adopts this system for the same reason. This passive shutdown design concept is combined with a group of secondary control rod drive mechanisms (SCRDM). The system automatically releases the control rod assembly (CRA) around the set temperature, and then drops the CRA by gravity without any external control signals and any actuating power in an emergency of the reactor. This paper describes the parametric design study of a passive shutdown system, which consists of a thermal expansion device, an electromagnet, and a secondary control rod assembly head. The conceptual design values of each component are also suggested. Parametric calculations are performed to check the suitability of the performance requirements of the thermal expansion device and electromagnets

  13. Fuel Supply Shutdown Facility Interim Operational Safety Requirements

    International Nuclear Information System (INIS)

    BENECKE, M.W.

    2000-01-01

    The Interim Operational Safety Requirements for the Fuel Supply Shutdown (FSS) Facility define acceptable conditions, safe boundaries, bases thereof, and management of administrative controls to ensure safe operation of the facility

  14. Porovnanie slovenského a českého start-up ekosystému

    OpenAIRE

    Pipasová, Jaroslava

    2017-01-01

    This master thesis deals with the comparison of startup ecosystems in the Czech Republic and Slovakia. The goal is to discover which of these two countries has more developed startup ecosystem. The first chapter aims to define startup and illustrates its importance and development in both countries. The second chapter analyzes the characteristic of startup ecosystem, startup financing and supporting institutions in the 2 countries. The final chapter contains a comparison of the startup ecosys...

  15. Preliminary experiment of non-induced plasma current startup on SUNIST spherical tokamak

    International Nuclear Information System (INIS)

    He Yexi; Zhang Liang; Xie Lifeng; Tang Yi; Yang Xuanzong; Fu Hongjun

    2005-01-01

    Non-inductive plasma current startup is an important motivation on the SUNIST spherical tokamak. In this experiment, a 100 kW, 2.45 GHz magnetron microwave system has been applied to the plasma current startup. Besides the toroidal field, a vertical field was applied to generate a preliminary toroidal plasma current without action of the central solenoid. As the evidence of the plasma current startup by the vertical field drift effect, the direction of the plasma current is changed with the changing direction of the vertical field during ECR startup discharge. We have also observed the plasma current maximum by scanning the vertical field in both directions. Additionally, we have used electrode discharge to assist the ECR current startup. (author)

  16. Startup transient simulation for natural circulation boiling water reactors in PUMA facility

    International Nuclear Information System (INIS)

    Kuran, S.; Xu, Y.; Sun, X.; Cheng, L.; Yoon, H.J.; Revankar, S.T.; Ishii, M.; Wang, W.

    2006-01-01

    In view of the importance of instabilities that may occur at low-pressure and -flow conditions during the startup of natural circulation boiling water reactors, startup simulation experiments were performed in the Purdue University Multi-Dimensional Integral Test Assembly (PUMA) facility. The simulations used pressure scaling and followed the startup procedure of a typical natural circulation boiling water reactor. Two simulation experiments were performed for the reactor dome pressures ranging from 55 kPa to 1 MPa, where the instabilities may occur. The experimental results show the signature of condensation-induced oscillations during the single-phase-to-two-phase natural circulation transition. The results also suggest that a rational startup procedure is needed to overcome the startup instabilities in natural circulation boiling water reactor designs

  17. Optimization of operation conditions for the startup of aerobic granular sludge reactors biologically removing carbon, nitrogen, and phosphorous.

    Science.gov (United States)

    Lochmatter, Samuel; Holliger, Christof

    2014-08-01

    The transformation of conventional flocculent sludge to aerobic granular sludge (AGS) biologically removing carbon, nitrogen and phosphorus (COD, N, P) is still a main challenge in startup of AGS sequencing batch reactors (AGS-SBRs). On the one hand a rapid granulation is desired, on the other hand good biological nutrient removal capacities have to be maintained. So far, several operation parameters have been studied separately, which makes it difficult to compare their impacts. We investigated seven operation parameters in parallel by applying a Plackett-Burman experimental design approach with the aim to propose an optimized startup strategy. Five out of the seven tested parameters had a significant impact on the startup duration. The conditions identified to allow a rapid startup of AGS-SBRs with good nutrient removal performances were (i) alternation of high and low dissolved oxygen phases during aeration, (ii) a settling strategy avoiding too high biomass washout during the first weeks of reactor operation, (iii) adaptation of the contaminant load in the early stage of the startup in order to ensure that all soluble COD was consumed before the beginning of the aeration phase, (iv) a temperature of 20 °C, and (v) a neutral pH. Under such conditions, it took less than 30 days to produce granular sludge with high removal performances for COD, N, and P. A control run using this optimized startup strategy produced again AGS with good nutrient removal performances within four weeks and the system was stable during the additional operation period of more than 50 days. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Procedure of determination of the nuclear reactor start-up power

    International Nuclear Information System (INIS)

    Brandt, K.D.; Griese, K.; Guehne, F.

    1985-01-01

    The invention has been aimed at a determination of the thermal reactor power during the start-up period and the commissioning resp. preferably under an extremely low thermal power in a range from 0.001 to 1%. In addition to it also the power range up to 100% shall be covered. The external gamma-ray flux density as a function of the thermal reactor power is measured in several overlapping partial measuring ranges. A suitable measuring device transforms the input signals into an electrically measured quantity proportional to the reactor power

  19. Quel contrôle de gestion pour les startups ?

    OpenAIRE

    Meyssonnier , François

    2015-01-01

    Une étude de huit PME fondées sur la science permet d’identifier les spécificités du contrôle de gestion des startups. Dans les startups émergentes le dirigeant n’utilise que des linéaments de contrôle de gestion essentiellement pour développer son approche cognitive du business model. Dans les startups en croissance le contrôle de gestion a un rôle de garde-fou et les outils de pilotage de la performance sont utilisés essentiellement de façon interactive et pour la prévision. Les principaux ...

  20. Reliability analysis of self-actuated shutdown system

    International Nuclear Information System (INIS)

    Itooka, S.; Kumasaka, K.; Okabe, A.; Satoh, K.; Tsukui, Y.

    1991-01-01

    An analytical study was performed for the reliability of a self-actuated shutdown system (SASS) under the unprotected loss of flow (ULOF) event in a typical loop-type liquid metal fast breeder reactor (LMFBR) by the use of the response surface Monte Carlo analysis method. Dominant parameters for the SASS, such as Curie point characteristics, subassembly outlet coolant temperature, electromagnetic surface condition, etc., were selected and their probability density functions (PDFs) were determined by the design study information and experimental data. To get the response surface function (RSF) for the maximum coolant temperature, transient analyses of ULOF were performed by utilizing the experimental design method in the determination of analytical cases. Then, the RSF was derived by the multi-variable regression analysis. The unreliability of the SASS was evaluated as a probability that the maximum coolant temperature exceeded an acceptable level, employing the Monte Carlo calculation using the above PDFs and RSF. In this study, sensitivities to the dominant parameter were compared. The dispersion of subassembly outlet coolant temperature near the SASS-was found to be one of the most sensitive parameters. Fault tree analysis was performed using this value for the SASS in order to evaluate the shutdown system reliability. As a result of this study, the effectiveness of the SASS on the reliability improvement in the LMFBR shutdown system was analytically confirmed. This study has been performed as a part of joint research and development projects for DFBR under the sponsorship of the nine Japanese electric power companies, Electric Power Development Company and the Japan Atomic Power Company. (author)

  1. 78 FR 49553 - Three Mile Island, Unit 2; Post Shutdown Decommissioning Activities Report

    Science.gov (United States)

    2013-08-14

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 50-320; NRC-2013-0183] Three Mile Island, Unit 2; Post Shutdown Decommissioning Activities Report AGENCY: Nuclear Regulatory Commission. ACTION: Notice of receipt... Shutdown Decommissioning Activity Report (PSDAR) for Three Mile Island, Unit 2 (TMI-2). The PSDAR provides...

  2. A Sales Execution Strategy Guide for Technology Startups

    Directory of Open Access Journals (Sweden)

    Ian Gilbert

    2011-10-01

    Full Text Available The majority of startups fail to consider sales execution as part of their overall strategy. This article demonstrates how a sales execution strategy can help a company take a product or service to market more efficiently and effectively by focusing on the customers that are key to generating revenue. Combined with techniques for recruiting effectively and measuring sales outcomes, a sales execution strategy helps technology startups exceed growth aspirations and potentially reduce or even eliminate the requirement for external investment. In this article, we first describe the focus of assistance currently given to startups and the reasons why sales execution strategies are often overlooked. Next, we outline recommendations for developing, implementing, and supporting a sales execution strategy. Finally, we summarize the key points presented in the article.

  3. Performance evaluation of startup for a yeast membrane bioreactor (MBRy) treating landfill leachate.

    Science.gov (United States)

    Amaral, Míriam C S; Gomes, Rosimeire F; Brasil, Yara L; Oliveira, Sílvia M A; Moravia, Wagner G

    2017-12-06

    The startup process of a membrane bioreactor inoculated with yeast biomass (Saccharomyces cerevisiae) and used in the treatment of landfill leachate was evaluated. The yeast membrane bioreactor (MBRy) was inoculated with an exogenous inoculum, a granulated active dry commercial bakers' yeast. The MBRy was successfully started up with a progressive increase in the landfill leachate percentage in the MBRy feed and the use of Sabouraud Dextrose Broth. The membrane plays an important role in the startup phase because of its full biomass retention and removal of organic matter. MBRy is a suitable and promising process to treat recalcitrant landfill leachate. After the acclimation period, the COD and NH 3 removal efficiency reached values of 72 ± 3% and 39 ± 2% respectively. MBRy shows a low membrane-fouling potential. The membrane fouling was influenced by soluble microbial products, extracellular polymeric substances, sludge particle size, and colloidal dissolved organic carbon.

  4. Elementary calculation of the shutdown delay of a pile

    International Nuclear Information System (INIS)

    Yvon, J.

    1949-04-01

    This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)

  5. Assessment on Startup Ramp Rate and Threshold Power of OPR1000

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kiyoung; Kim, Yongbae; Cha, Gyunho; Kim, Yongdeog [Korea Hydro and Nuclear Power Co., Ltd., Daejeon (Korea, Republic of)

    2014-05-15

    This paper summarizes PCI assessment according to several startup ramp rates and threshold power assessment of OPR1000. The definition of threshold power is maximum value in power range that can increase startup ramp rate rapidly. FALCON code is used for PCI assessment and it is analyzed for once-burned fuel because it is the most sensitive to PCI failure. The objective of the PCI analysis is to assess the cladding stress state under various power ramp conditions at the peak power node location. The PCI analyses were conducted for the once-burned fuel from the start of the second cycle to plant power 100%. This paper presents both the PCI analysis according to startup ramp rates and threshold power assessment result like below. · The more startup ramp rate is increased, the more PCI failure probability is decreased in low power range (≤ 40%). · PCI failure is not occurred even though startup ramp rate is 10%/hr until the plant power reaches 55%.

  6. Assessment on Startup Ramp Rate and Threshold Power of OPR1000

    International Nuclear Information System (INIS)

    Kim, Kiyoung; Kim, Yongbae; Cha, Gyunho; Kim, Yongdeog

    2014-01-01

    This paper summarizes PCI assessment according to several startup ramp rates and threshold power assessment of OPR1000. The definition of threshold power is maximum value in power range that can increase startup ramp rate rapidly. FALCON code is used for PCI assessment and it is analyzed for once-burned fuel because it is the most sensitive to PCI failure. The objective of the PCI analysis is to assess the cladding stress state under various power ramp conditions at the peak power node location. The PCI analyses were conducted for the once-burned fuel from the start of the second cycle to plant power 100%. This paper presents both the PCI analysis according to startup ramp rates and threshold power assessment result like below. · The more startup ramp rate is increased, the more PCI failure probability is decreased in low power range (≤ 40%). · PCI failure is not occurred even though startup ramp rate is 10%/hr until the plant power reaches 55%

  7. 75 FR 39247 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Science.gov (United States)

    2010-07-08

    ... the occurrence and duration of any startup, shutdown, or malfunction in the operation of an affected... collection of information is estimated to average 100.5 hours per response. Burden means the total time... Total Annual Cost: $597,254, which includes $465,654 in labor costs, $0 in capital/startup costs, and...

  8. Interdisciplinarity in Tech Startups Development – Case Study of ‘Unistartapp’ Project

    Directory of Open Access Journals (Sweden)

    Kopera Sebastian

    2018-03-01

    Full Text Available Empirical data as well as scientific reports confirm that startups require diverse, in-house competencies in order to achieve market success. However, while technology-related competencies are usually brought to new tech ventures by their founders, there is a significant deficiency of market- and management-related competencies, which is reflected in the statistics of common startup failure reasons. In this context, a question arises: how interdisciplinarity of knowledge and competencies can be built into the very core of tech startups? The text addresses this question by zeroing in on the role of universities in this process. In the first part, the specificity of tech startups is analyzed. The next chapter overviews the hitherto academy-related startup education environment together with its shortcomings as far as interdisciplinarity is concerned. Finally, the case study of innovative and interdisciplinary academic ecosystem, which was built and tested within the project UniStartApp, is presented and discussed together with related lessons learned. The text is concluded with final remarks on challenges involved in embedding interdisciplinarity into startup education ecosystem.

  9. Reload safety evaluation of boron dilution accident related to shutdown margin proportional to boron concentration

    International Nuclear Information System (INIS)

    Zee, Sung Kyun; Lee, Ki Bog; Song, Jae Woong

    1993-06-01

    This report investigates the efficient safety evaluation method and analysis procedure on Boron Dilution Accident(BDA) under the proportional shutdown margin to boron concentration. Also investigated are problems caused by applying this shutdown margin limit. Through this investigation, the safety of Kori-3 Cycle-8, Yonggwang-2 Cycle-7, Kori-4 Cycle-8 and Yonggwang-1 Cycle-8 with respect to BDA is verified. In order to satisfy the shutdown margin requirement in the Technical Specifications, it is shown that the High Flux Alarm at Shutdown Setting for Kori-4 Cycle-8 and Yonggwang-1 Cycle-8 at Mode 5 should be set at 2 or the Technical Specification should be revised. (Author)

  10. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, Steven J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Best, Ralph E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ross, Steven B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buxton, Kenneth A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); England, Jeffery L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McConnell, Paul E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Massaro, Lawrence M. [Federal Railroad Administration (FRA) (United States); Jensen, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-10-01

    This report presents a preliminary evaluation of removing used nuclear fuel (UNF) from 12 shutdown nuclear power plant sites. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites are Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. The evaluation was divided into four components: characterization of the UNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory; a description of the on-site infrastructure and conditions relevant to transportation of UNF and GTCC waste; an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing UNF and GTCC waste, including identification of gaps in information; and, an evaluation of the actions necessary to prepare for and remove UNF and GTCC waste. The primary sources for the inventory of UNF and GTCC waste are the U.S. Department of Energy (DOE) RW-859 used nuclear fuel inventory database, industry sources such as StoreFUEL and SpentFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of site and near-site transportation infrastructure and experience included observations and information collected during visits to the Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion sites; information provided by managers at the shutdown sites; Facility Interface Data Sheets compiled for DOE in 2005; Services Planning Documents prepared for DOE in 1993 and 1994; industry publications such as Radwaste Solutions; and Google Earth. State and Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative participated in six of the shutdown site

  11. Team Heterogeneity in Startups and its Development over Time

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Müller, Bettina

    We investigate the workforce heterogeneity of startups with respect to education, age and wages. Our explorative study uses data on the population of 1,614 Danish firms founded in 1998. We track these firms until 2001 which enables us to analyze changes in workforce composition over time. Such a ......We investigate the workforce heterogeneity of startups with respect to education, age and wages. Our explorative study uses data on the population of 1,614 Danish firms founded in 1998. We track these firms until 2001 which enables us to analyze changes in workforce composition over time....... Our result holds both for non-knowledge-based and, to a lesser extent, knowledge-based startups. This seems surprising since a vast management literature advocates heterogeneous teams. The difficulties associated with workforce heterogeneity (like affective conflict or coordination cost) as well...... as “homophily” (people’s inclination to bound with others with similar characteristics) hence appear to generally overweigh the benefits of heterogeneity (like greater variety in perspectives or more creativity). We also document that workforces become more heterogeneous over time startups add workers...

  12. New start-up channels and multichannel analyzer at the RB reactor; Novi start-up kanali i videkanalni analizator na reaktoru Rb

    Energy Technology Data Exchange (ETDEWEB)

    Sotic, O; Markovic, H; Vranic, S; Dimitrijevic, Z; Pesic, M [Boris Kidric Institute of Nuclear Sciences Vinca, Beograd (Yugoslavia)

    1978-01-15

    New start-up channels and a multichannel analyzer were purchased in 1977 for the RB reactor. Both start-up channels contain BF{sub 3} neutron detectors, preamplifier, amplifier, single-channel analyzer, scaler, ratemeter, control unit, recording instrument. This document contains detailed technical description of these devices as well as characteristics of the multichannel analyzer which is being tested and will be used for measuring irradiation in the vicinity of the reactor.

  13. The geography of new firm formation: Evidence from independent start-ups and new subsidiaries in the Netherlands

    NARCIS (Netherlands)

    Bosma, N.; van Stel, A.; Suddle, K.

    2008-01-01

    This paper investigates to what extent determinants of the rate of independent start-ups and the rate of new subsidiaries are different. Using a regional database for the Netherlands over the period 1988-2002, we investigate the impact of two types of agglomeration effects, localization and

  14. Strategies for Reducing the Start-up Operation of Microbial Electrochemical Treatments of Urban Wastewater

    Directory of Open Access Journals (Sweden)

    Zulema Borjas

    2015-12-01

    Full Text Available Microbial electrochemical technologies (METs constitute the core of a number of emerging technologies with a high potential for treating urban wastewater due to a fascinating reaction mechanism—the electron transfer between bacteria and electrodes to transform metabolism into electrical current. In the current work, we focus on the model electroactive microorganism Geobacter sulfurreducens to explore both the design of new start-up procedures and electrochemical operations. Our chemostat-grown plug and play cells, were able to reduce the start-up period by 20-fold while enhancing chemical oxygen demand (COD removal by more than 6-fold during this period. Moreover, a filter-press based bioreactor was successfully tested for both acetate-supplemented synthetic wastewater and real urban wastewater. This proof-of-concept pre-pilot treatment included a microbial electrolysis cell (MEC followed in time by a microbial fuel cell (MFC to finally generate electrical current of ca. 20 A·m−2 with a power of 10 W·m−2 while removing 42 g COD day−1·m−2. The effective removal of acetate suggests a potential use of this modular technology for treating acetogenic wastewater where Geobacter sulfurreducens outcompetes other organisms.

  15. Electron cyclotron resonance heating assisted plasma startup in the Tore Supra tokamak

    International Nuclear Information System (INIS)

    Bucalossi, J.; Hertout, P.; Lennholm, M.; Saint-Laurent, F.; Bouquey, F.; Darbos, C.; Traisnel, E.

    2009-04-01

    ECRH assisted plasma startup at fundamental resonance is investigated in Tore Supra in view of ITER operation. ECRH pre-ionisation is found to be very efficient allowing plasma initiation in a wide range of pre-fill pressure compared to ohmic startup. Reliable assisted startup has been achieved at the ITER reference toroidal electric field (0.3 V/m) with 160 kW of ECRH. Resonance location scan indicates that the plasma is initiated at the resonance location and that the plasma current channel position had to be real-time controlled since the very beginning of the discharge to obtain robust plasma startup. (authors)

  16. Novel start-up circuit with enhanced power-up characteristic for bandgap references

    DEFF Research Database (Denmark)

    Tuan Vu, Cao; Wisland, Dag T.; Lande, Tor Sverre

    This paper presents a new start-up circuit for low-power bandgap reference (BGR) voltage generators. The BGR is designed for providing a stable 0.3 V power supply for application in low power wireless sensor nodes. The BGR has an enhanced power-up characteristic and demonstrates a reduction...... of the total stand-by current. Simulated results confirm that the proposed start-up circuit does not affect the performance of the BGR even though the supply voltage (VDD) is higher and has more stable power-up characteristic than the conventional start-up circuits. The new start-up circuit is designed with 65...

  17. Extending reactor time-to-poison and reducing poison shutdown time by pre-shutdown power alterations

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, Edward

    1963-10-15

    Manipulation of reactor power prior to shutdown and increasing the time- to-poison a sufficient amount to enable the required maintenance work to be completed and the reactor immediately restarted are discussed. The method employed in the NRU Reactor to gain the maximum timeto-poison with the least production loss is outlined. The method is based on intuition and is described by means of an analog of the iodine--xenon equations rather than the equations themselves. (C.E.S.)

  18. 77 FR 70750 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Science.gov (United States)

    2012-11-27

    ... occurrence and duration of any startup, shutdown, or malfunction in the operation of an affected facility or..., and annually. Estimated Total Annual Hour Burden: 100,854. Estimated Total Annual Cost: $10,802,579, which includes $9,765,779 in labor costs, no capital/startup costs, and $1,036,800 in operation and...

  19. Development of advanced automatic operation system for nuclear ship. 1. Perfect automatic normal operation

    International Nuclear Information System (INIS)

    Nakazawa, Toshio; Yabuuti, Noriaki; Takahashi, Hiroki; Shimazaki, Junya

    1999-02-01

    Development of operation support system such as automatic operating system and anomaly diagnosis systems of nuclear reactor is very important in practical nuclear ship because of a limited number of operators and severe conditions in which receiving support from others in a case of accident is very difficult. The goal of development of the operation support systems is to realize the perfect automatic control system in a series of normal operation from the reactor start-up to the shutdown. The automatic control system for the normal operation has been developed based on operating experiences of the first Japanese nuclear ship 'Mutsu'. Automation technique was verified by 'Mutsu' plant data at manual operation. Fully automatic control of start-up and shutdown operations was achieved by setting the desired value of operation and the limiting value of parameter fluctuation, and by making the operation program of the principal equipment such as the main coolant pump and the heaters. This report presents the automatic operation system developed for the start-up and the shutdown of reactor and the verification of the system using the Nuclear Ship Engineering Simulator System. (author)

  20. Factors influencing performance within startup assistance organizations

    Directory of Open Access Journals (Sweden)

    Ceaușu Ioana

    2017-07-01

    Full Text Available Startup assistance organizations, and especially business accelerators have gained a lot of traction in the last years, captioning not only the attention of the public, but most importantly that of investors and other stakeholders. It has become a challenge for many all around the world to develop such programs, but many have failed or did not have their expected results, meaning medium to long-term sustainable and profitable alumni start-ups. As high amounts of resources, both human and financial, are being invested in the design and development of such programs, it is important to understand what sets apart the successful business acceleration programs from the ones that fail. The current paper is reviewing the up-to-date theoretical literature and studies on the matter at hand, in order to identify the most relevant factors influencing startup assistance organizations’ performance. The objective behind identifying these factors is to get a better understanding of best practices of such successful programs and set the basis for future research regarding the development of a set of metrics for more accurately measuring their performance.

  1. Trends vs. reactor size of passive reactivity shutdown and control performance

    International Nuclear Information System (INIS)

    Wade, D.C.; Fujita, E.K.

    1988-01-01

    The focus of the US advanced reactor program since the cancellation of CRBR has been on inherent safety and cost reduction. The notion is to so design the reactor that in the event of an off normal condition, it brings itself to a safe shutdown condition and removes decay heat by reliance on ''inherent processes'' i.e., without reliance on devices requiring switching and outside sources of power. Such a reactor design would offer the potential to eliminate costly ''Engineered Safety Features,'' to lower capital costs, and to assuage public unease concerning reactor safety. For LMR concepts, the goal of passive reactivity shutdown has been approached in the US by designing the reactors for favorable relationships among the power, power/flow, and inlet temperature coefficients of reactivity, for high internal conversion ratio (yielding small burnup control swing), and for a primary pump coastdown time appropriately matched to the delayed neutron hold back of power decay upon negative reactivity input. The use of sodium bonded metallic fuel pins has facilitated the achievement of the passive shutdown design goals as a consequence of their high thermal conductivity and high effective heavy metal density. Alternately, core designs based on derated oxide pins may be able to achieve the passive shutdown features at the cost of larger core volume and increased initial fissile inventory. 8 refs., 12 figs., 1 tab

  2. Seismic qualification of SPX1 shutdown systems - tests and calculations

    International Nuclear Information System (INIS)

    Brochard, D.; Buland, P.

    1988-01-01

    The SUPERPHENIX 1 shutdown system is composed of two main systems: the Complementary Shutdown System SAC (Systeme d'Arret Complementaire) and the Primary Shutdown System (SCP) (Systeme de Commande Principal). In case of a seismic event, the insertability of the different shutdown systems has to be demonstrated. Tests have been performed on the SAC and have shown that this system was not sensitive to the seismic excitation (the drop time increases of 10% at SSE level). For the SCP, as an analytical demonstration was felt difficult to achieve, it was decided to perform a full scale testing program. These tests have been performed for the two types of SCP which are present in Superphenix: SCP 1 (Creusot Loire design), SCP 2 (Novatome design). As there was no existing facility in France to test this kind of slender structure (21 metres high) a new facility named VESUBIE was designed and installed in an existing pit located at the Saclay nuclear research center. The objectives of the tests were the following: to demonstrate insertability of control rod; to demonstrate absence of seismic induced damage to the SCP; to measure increase of scram time; to measure seismic induced stresses; to obtain data for code correlation. After completion of the tests, measurements have been correlated with results obtained from a non-linear finite element model. Time history correlations were achieved for SCP 1. Afterwards a calculation was performed in hot condition to find if there was some effect of temperature on SCP seismic response. 2 refs, 8 figs

  3. The Core Interaction of Platforms: How Startups Connect Users and Producers

    Directory of Open Access Journals (Sweden)

    Heidi M. E. Korhonen

    2017-09-01

    Full Text Available The platform economy is disrupting innovation while presenting both opportunities and challenges for startups. Platforms support value creation between multiple participant groups, and this operationalization of an ecosystem’s value co-creation represents the “core interaction” of a platform. This article focuses on that core interaction and studies how startups connect producers and users in value-creating core interaction through digital platforms. The study is based on an analysis of 29 cases of platform startups interviewed at a leading European startup event. The studied startups were envisioning even millions of users and hundreds or thousands of producers co-creating value on their platforms. In such platform businesses, our results highlight the importance of attracting a large user pool, providing novel services to those users, offering a new market for producers, supporting the core interaction in various ways, and utilizing elements of the platform canvas – an adaptation of the business model canvas, which we have accommodated for platform-based business models – to accomplish these goals.

  4. Statement on the first research on digital startups in Poland

    Directory of Open Access Journals (Sweden)

    Agnieszka Skala

    2016-10-01

    Full Text Available The objective of the paper is to present the results of the first study of Polish startups’ ecosystem as the first stage of a larger study of digital economy landscape in Poland. The first estimate of the number of Polish startups amounts to 2400 entities. The publication presents the first survey Polish startups that marks the beginning of cyclical studies on enterprises belonging to the digital economy in Poland. The study was conducted among 423 entities using an in-house questionnaire prepared based on the author’s own knowledge. Results are discussed. Startups most often consider themselves software producers who follow the SaaS model and operate in the following industries: mobile apps, e-commerce and Internet services. Nearly one in three startups achieve 50% annual revenue growth, while in one-fifth such growth exceeds 100%. Almost two thirds of Polish startups are financed exclusively from own funds. It is necessary to repeat and deepen the study in order to determining the significance of the digital industry in the economy of Poland and the CEE region. The originality of this work lies in taking this subject for the first time in Polish literature and in elaborating the proposition of a “startup” term’s definition.

  5. 40 CFR 63.1111 - Startup, shutdown, and malfunction.

    Science.gov (United States)

    2010-07-01

    ... corrective action taken to restore malfunctioning process and air pollution control equipment to its normal... such affected source (including associated air pollution control equipment and CPMS) in a manner consistent with safety and good air pollution control practices for minimizing emissions to the extent...

  6. Evaluation of reactivity shutdown margin for nuclear fuel reload optimization

    International Nuclear Information System (INIS)

    Wong, Hing-Ip; Maldonado, G.I.

    1995-01-01

    The FORMOSA-P code is a nuclear fuel management optimization package that combines simulated annealing (SA) and nodal generalized perturbation theory (GPT). Recent studies at Electricite de France (EdF-Clamart) have produced good results for power-peaking minimizations under multiple limiting control rod configurations. However, since the reactivity shutdown margin is not explicitly treated as an objective or constraint function, then any optimal loading patterns (LPs) are not guaranteed to yield an adequate shutdown margin (SDM). This study describes the implementation of the SDM calculation within a FORMOSA-P optimization. Maintaining all additional computational requirements to a minimum was a key consideration

  7. An eigenexpansion technique for modelling plasma start-up

    International Nuclear Information System (INIS)

    Pillsbury, R.D.

    1989-01-01

    An algorithm has been developed and implemented in a computer program that allows the estimation of PF coil voltages required to start-up an axisymmetric plasma in a tokamak in the presence of eddy currents in toroidally continuous conducting structures. The algorithm makes use of an eigen-expansion technique to solve the lumped parameter circuit loop voltage equations associated with the PF coils and passive (conducting) structures. An example of start-up for CIT (Compact Ignition Tokamak) is included

  8. Digital Innovations: Startup Marketing Strategy for Global Growth

    OpenAIRE

    Gröhn, Hanna

    2017-01-01

    This thesis discusses the relatively new phenomena of innovative digital products created by startup companies, who often must scale globally fast, before the volatile trends or the fierce competition of the digital marketspace take over. International entry itself is no longer the issue, but rather standing out in the crowd while balancing resources and flexibility. The focus is on how startups can induce global growth and tackle structural obstacles by means of marketing strategy. The t...

  9. 40 CFR 60.2953 - What information must I submit prior to initial startup?

    Science.gov (United States)

    2010-07-01

    ... initial startup? 60.2953 Section 60.2953 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... initial startup? You must submit the information specified in paragraphs (a) through (e) of this section prior to initial startup. (a) The type(s) of waste to be burned. (b) The maximum design waste burning...

  10. 40 CFR 60.2195 - What information must I submit prior to initial startup?

    Science.gov (United States)

    2010-07-01

    ... initial startup? 60.2195 Section 60.2195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY..., 2001 Recordkeeping and Reporting § 60.2195 What information must I submit prior to initial startup? You... startup. (a) The type(s) of waste to be burned. (b) The maximum design waste burning capacity. (c) The...

  11. The Emergence of the Lean Global Startup as a New Type of Firm

    Directory of Open Access Journals (Sweden)

    Erik Stavnsager Rasmussen

    2015-11-01

    Full Text Available This article contributes to the interplay between international entrepreneurship, innovation networks, and early internationalization research by emphasizing the need to conceptualize and introduce a new type of firm: the lean global startup. It discussed two different paths in linking the lean startup and born-global internationalization strategies. The first path refers to generic lean startups that have undertaken a rapid internationalization strategy (i.e., lean-to-global startups. The second path refers to startups that have started operating on global scale since their inception and adopted the lean startup approach by seamlessly synergizing their global and lean product development activities. The article emphasizes several aspects that could be used as part of the theoretical foundation for conceptualizing lean global startups as a special new type of firm: i the emergent nature of their business models, including the challenges of partnership development on a global scale; ii the inherently relational nature of the global resource allocation processes; iii the integration of the entrepreneurial, effectuation, and global marketing perspectives; iv the need to deal with a high degree of uncertainty, including the uncertainty associated with cross-border business operations; and v linking the ex-ante characteristics of lean startups with the ex-post characteristics of born-global firms in order to develop a technology adoption marketing perspective that considers the “crossing the chasm” process as a successful entry into a global market niche.

  12. Component failures that lead to manual shutdowns

    International Nuclear Information System (INIS)

    1979-01-01

    The data for this report are taken from a population of thirty-five LWRs, al of which differ appreciably in size, design, and age. Appendix A provides a graphical display of the number of manual shutdowns per operating year as a function of plant age, with the frequency adjusted to reflect plant availability

  13. Start-up procedure

    International Nuclear Information System (INIS)

    Marchl, A.; Krebs, W.D.; Aleite, W.

    1975-01-01

    The start-up procedure will be shown on a pressurized water reactor, although most of the activities will occur similarly in other reactor types. The commissioning time can be divided into 5 sections, the phases A to E together lasting 26 months. Subsequently there are a test run of one month and the handling-over of the plant to the operator. A survey of the commissioning sections with several important main events is shown. (orig./TK) [de

  14. How Types of Organisational Culture Shapes Successful Start-ups within Malaysia

    OpenAIRE

    Kuah, Shen Yang

    2016-01-01

    Start-ups is the new wave of firms which are now mushrooming around Malaysia. However, as this wave is still at its infancy the success rate of start-ups in Malaysia is extremely low. It has been long established that organisational culture does indeed effect the performance of a firm, however there haven’t been any reports on the effect of organisational culture on the success of start-ups. The objective of this report is to investigate how different types of organisational cultures contribu...

  15. Software for physical start-up console

    International Nuclear Information System (INIS)

    Arbet, L.; Suchy, R.

    1991-01-01

    The physical start-up console comprises an PC AT-based control unit equipped with an 80386 processor, and information input/output units. The basic functions to be fulfilled by the control unit software include data acquisition related to the following parameters: neutron physics properties of the reactor core (neutron fluxes recorded by ionization chambers and reactivity recorded by a digital reactimeter), positions of the reactor core control elements (by the digital position meter) and reactor core control measurements, and technological quantities requisite for evaluating physical start-up tests. The measured and calculated data are shown on the control unit display. The setup of the data acquisition system and of user programs is dealt with, and characteristics of the user processes are briefly described. (Z.S.)

  16. Impacts of reactivity feedback uncertainties on inherent shutdown in innovative designs

    International Nuclear Information System (INIS)

    Mueller, C.J.

    1986-01-01

    The concept of inherent shutdown is emphasized in the approach to the design of innovative, small pool-type liquid-metal reactors (LMRs). This paper reports an evaluation of reactivity feedback uncertainties used in the analyses of anticipated transients without scram for innovative LMRs, and the associated impacts on safety margins and inherent shutdown success probabilities on unprotected loss-of-flow (LOF) events. It then assesses the ultimate importance of these uncertainties on LOF and transient overpower events in evolving metal and oxide innovative designs

  17. Impacts of reactivity feedback uncertainties on inherent shutdown in innovative designs

    International Nuclear Information System (INIS)

    Mueller, C.J.

    1986-01-01

    The concept of ''inherent shutdown'' is emphasized in the approach to the design of innovative, small pool-type liquid metal reactors (LMRs). This paper reports an evaluation of reactivity feedback uncertainties used in the analyses of anticipated transients without scram (ATWS) for innovative LMRs, and the associated impacts on safety margins and inherent shutdown success probabilities on unprotected loss-of-flow (LOF) events. It then assesses the ultimate importance of these uncertainties on LOF and transient overpower (TOP) events in evolving metal and oxide innovative designs

  18. Analytic method study of point-reactor kinetic equation when cold start-up

    International Nuclear Information System (INIS)

    Zhang Fan; Chen Wenzhen; Gui Xuewen

    2008-01-01

    The reactor cold start-up is a process of inserting reactivity by lifting control rod discontinuously. Inserting too much reactivity will cause short-period and may cause an overpressure accident in the primary loop. It is therefore very important to understand the rule of neutron density variation and to find out the relationships among the speed of lifting control rod, and the duration and speed of neutron density response. It is also helpful for the operators to grasp the rule in order to avoid a start-up accident. This paper starts with one-group delayed neutron point-reactor kinetics equations and provides their analytic solution when reactivity is introduced by lifting control rods discontinuously. The analytic expression is validated by comparison with practical data. It is shown that the analytic solution agrees well with numerical solution. Using this analytical solution, the relationships among neutron density response with the speed of lifting control rod and its duration are also studied. By comparing the results with those under the condition of step inserted reactivity, useful conclusions are drawn

  19. 26 CFR 1.195-1T - Election to amortize start-up expenditures (temporary).

    Science.gov (United States)

    2010-04-01

    ... business, or $5,000 (reduced (but not below zero) by the amount by which the start-up expenditures exceed... beginning with the month in which the active trade or business begins. All start-up expenditures that relate to the active trade or business are considered in determining whether the start-up expenditures...

  20. Organising a conference? Think about what you can do for start-ups!

    CERN Multimedia

    David Mazur

    2016-01-01

    ICTR-PHE 2016 welcomed 16 exhibitors and sponsors as part of its industrial exhibition. If you have ever (co-)organised a large scientific conference, you almost certainly have your own list of major industrial actors who could be interested in becoming exhibitors or sponsors.   The six start-ups present at ICTR-PHE 2016 – Oncoradiomics, Colnec Health, Dixit Solutions, e-Learning4Health, I-See Computing and SmART Scientific Solutions (not pictured). (Image: Salvatore Fiore) ICTR-PHE has shown that scientific conferences can have a catalysing role in transforming young start-ups and spin-off companies into the key industrial players of tomorrow. A special start-up corner was provided in the industrial exhibition, where small stands were made available for a modest fee to start-ups and spin-off companies in fields relevant to the conference theme, together with a 5-minute timeslot for a pitch to the audience. Six start-ups, from the Netherlands, Italy and France...

  1. Procurement principles and vendor management in technological start-up companies

    OpenAIRE

    Jakobsson, Charlotta

    2016-01-01

    Denna studie är kopplad till direkta inköp inom teknologiska startup företag. Målet med studien är att undersöka vilka direktupphandlingsmetoder teknologiska startup företag använder sig avsamt att få reda på hur de sköter sina leverantörförhållanden. Ett vidare mål är att och på basis av resultaten ta fram inköpsrekommendationer för företagen och för Salusfin. Forskningen är begränsad till teknologiska startup företag samt deras direktupphandlings aktiviteter, och kan inte med säkerhet gener...

  2. Operational readiness review for the Waste Experimental Reduction Facility. Final report

    International Nuclear Information System (INIS)

    1993-11-01

    An Operational Readiness Review (ORR) at the Idaho National Engineering Laboratory's (INEL's) Waste Experimental Reduction Facility (WERF) was conducted by EG ampersand G Idaho, Inc., to verify the readiness of WERF to resume operations following a shutdown and modification period of more than two years. It is the conclusion of the ORR Team that, pending satisfactory resolution of all pre-startup findings, WERF has achieved readiness to resume unrestricted operations within the approved safety basis. ORR appraisal forms are included in this report

  3. H. B. Robinson Plant, Unit 2. Annual operating report for 1976

    International Nuclear Information System (INIS)

    1977-01-01

    The unit achieved a good performance record through the year, experiencing only short duration shutdowns or power reductions. Information is presented concerning operations, maintenance, shutdowns, and occupational radiation exposures. In November there was a scheduled refueling lasting 40 days. After a start-up physics test program, the unit achieved 100 percent power on December 22, 1976

  4. Start-up processes’ efficiency of turbine jet engines

    Directory of Open Access Journals (Sweden)

    Jankowski Antoni

    2016-12-01

    Full Text Available The paper presents diagnoses of example start-up processes of drive units built in military aircraft operated in the Dęblin's “School of Eaglets” during the flight. The significance of this process is very important, especially from the point of view of flight safety, especially as it concerns the training aircraft, on which officer cadets-candidates for pilots are trained. The diagnosis of the start-up process was conducted using data from on-board flight recorders recorded during a flight training, whose aim was an emergency launch of particular drive units, and with the help of the so-called phase mapping of the selected operating parameters of the particular flight drive systems. The standard diagram of typical start-up systems was shown, while presenting their base subassemblies. At the end, the obtained results and the main problems that need intervention were commented, as well as further preventive activities were proposed.

  5. Accident sequence analysis for a BWR [Boiling Water Reactor] during low power and shutdown operations

    International Nuclear Information System (INIS)

    Whitehead, D.W.; Hake, T.M.

    1990-01-01

    Most previous Probabilistic Risk Assessments have excluded consideration of accidents initiated in low power and shutdown modes of operation. A study of the risk associated with operation in low power and shutdown is being performed at Sandia National Laboratories for a US Boiling Water Reactor (BWR). This paper describes the proposed methodology for the analysis of the risk associated with the operation of a BWR during low power and shutdown modes and presents preliminary information resulting from the application of the methodology. 2 refs., 2 tabs

  6. [Start-up grants for young scientists in German medical universities : Can the clinical scientist be saved?

    Science.gov (United States)

    Pabst, R; Linke, P B; Neudeck, N B A; Schmiel, M; Ernst, S B

    2016-12-01

    German medical faculties currently have severe financial problems. There is the conflict between financing teaching medical students, inpatient and outpatient costs and supporting basic and applied research. Young postdocs can apply for a grant to start research projects to establish techniques on publishing data as a basis for applying for grants from the German Research Foundation or foundations with a critical review system. Successful applicants from the years 1998-2011 were asked to answer a questionnaire. The annual number of applications ranged from 28 to 96 per year. Within the first period of our analysis ranging from 1998 to 2004, a mean number of 69.5 % ± 14.0 % of submitted grant applications were approved annually in comparison to an average approval of 30.9 % ± 11 % in the years 2006-2001. In total 353 projects were funded with a mean amount of money for a project of approximately 18,640 EUR. The mean amount of external grant money following the start-up period was 7.2 times the money initially spent. That is an excellent return of investment. There were no differences between applicants from the department of surgery or department of internal medicine. In the meantime, 56 % of men and 42 % of women have achieved the academic degree university lecturer (privatdozent). Furthermore, 71 % of the participants evaluated this start-up research as supportive for their postdoctoral qualification (habilitation). The program for initial investment for young postdocs by internal start-up grants is overall successful.

  7. Advanced automation concepts applied to Experimental Breeder Reactor-II startup

    International Nuclear Information System (INIS)

    Berkan, R.C.; Upadhyaya, B.R.; Bywater, R.L.

    1991-08-01

    The major objective of this work is to demonstrate through simulations that advanced liquid-metal reactor plants can be operated from low power by computer control. Development of an automatic control system with this objective will help resolve specific issues and provide proof through demonstration that automatic control for plant startup is feasible. This paper presents an advanced control system design for startup of the Experimental Breeder Reactor-2 (EBR-2) located at Idaho Falls, Idaho. The design incorporates recent methods in nonlinear control with advanced diagnostics techniques such as neural networks to form an integrated architecture. The preliminary evaluations are obtained in a simulated environment by a low-order, valid nonlinear model. Within the framework of phase 1 research, the design includes an inverse dynamics controller, a fuzzy controller, and an artificial neural network controller. These three nonlinear control modules are designed to follow the EBR-2 startup trajectories in a multi-input/output regime. They are coordinated by a supervisory routine to yield a fault-tolerant, parallel operation. The control system operates in three modes: manual, semiautomatic, and fully automatic control. The simulation results of the EBR-2 startup transients proved the effectiveness of the advanced concepts. The work presented in this paper is a preliminary feasibility analysis and does not constitute a final design of an automated startup control system for EBR-2. 14 refs., 43 figs

  8. Loss of shutdown cooling during degassing in Doel 1

    International Nuclear Information System (INIS)

    1996-01-01

    The presentation describes loss of shutdown cooling event during degassing in Doel 1 reactor, including description of Doel 1 features,status of plant prior to incident, event sequence and incident causes

  9. Established Companies meet Start-ups : Case: A service to research developing business models in start-up hot spots around the globe

    OpenAIRE

    Eisenblätter, Simon

    2016-01-01

    This thesis presents a business model with the aim to improve conversation between traditional companies and newly established start-ups. The assumption that such conversation can be facilitated by scouting for innovation in start-up hot spots around the world, will be discussed throughout the paper. The purpose of this work is to lay out a plan which can be presented to a first range of possible customers, with the goal of negotiating a trial cooperation. Before introducing the busi...

  10. Comparison of Qualitative and Quantitative Risk Results for Shutdown Operation

    International Nuclear Information System (INIS)

    Oh, Hae Cheol; Kim, Myung Ki; Chung, Bag Soon; Seo, Mi Ro; Hong, Sung Yull

    2006-01-01

    The Defense-In-Depth philosophy is a fundamental concept of nuclear safety. The objective of Defense-In- Depth (DID) evaluation is to assess the level of Defense- In-Depth maintained during the various plant maintenance activities. Especially for shutdown and outage operations, the Defense-In-Depth might be challenged due to the reduction in redundancy and diversity resulting from the maintenance. The qualitative defense-in-depth evaluation using deterministic trees such as SFAT (Safety Function Assessment Tree), can provide 'Safety' related information on the levels of defense-in-depth according to the plant configuration including the levels of redundancy and diversity. For the more reasonable color decision of SFAT, it is necessary to identify the risk impact of degradation of redundancy and diversity of mitigation systems. The probabilistic safety analysis for the shutdown status can provide risk information related on the degradation of redundancy and diversity level for the safety functions during outage. Insights from the both methods for the plant status can be the same or different. The results of DID approach and PSA for the shutdown state are compared in this paper

  11. LHC Report: The shutdown work nearing completion

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    The work planned for the LHC injector chain during the winter shutdown is nearing completion. The PS Booster (PSB) and PS will be closed to access next week, and the control of machine access will be transferred to the CERN Control Centre in preparation for the resumption of machine operation. Hardware tests are being performed in all the machines.   Tests are under way in the LHC tunnel. The technical teams are putting the finishing touches to the work planned for the winter shutdown. At the Linac2, the PS Booster and the PS, work will be completed next week and hardware tests will be carried out soon after. POPS, the new powering system for the PS, will be commissioned for the first time in the coming days after the necessary preliminary tests have been carried out. At the SPS, various magnets have been replaced over recent weeks and the performance tests on the main power supply and other hardware tests will be able to start shortly. After that, the machine will be ready for operation with b...

  12. Evaluation of reactivity shutdown margin for nuclear fuel reload optimization

    International Nuclear Information System (INIS)

    Engrand, P.; Wong, H. I.; Maldonado, G.I.

    1996-01-01

    The FORMOSA-P code is a nuclear fuel management optimization package which combines simulated annealing (SA) and nodal generalized perturbation theory (GPT). Recent studies at Electricite de France have produced good results for power peaking minimizations under multiple limiting control rod configurations. However, since the reactivity shutdown margin is not explicitly treated as an objective or constraint function, then any optimal loading patterns (LPs) are not guaranteed to yield an adequate shutdown margin (SDM). This study describes the implementation of the SDM calculation within a FORMOSA-P optimization. Maintaining all additional computational requirements to a minimum was a key consideration. (authors). 4 refs., 2 figs

  13. Impact of shutdown risk on risk-based assessment of technical specifications

    International Nuclear Information System (INIS)

    Deriot, S.

    1992-10-01

    This paper describes the current work performed by the Research and Development Division of EDF concerning risk-based assessment of Operating Technical Specifications (OTS). The current risk-based assessment of OTS at EDF is presented. Then, the level 1 Probabilistic Safety Assessment of unit 3 of the Paluel nuclear power station (called PSA 1300) is described. It is fully computerized and takes into account the risk in shutdown states. A case study is presented. It shows that the fact of considering shutdown risk suggests that the current OTS should be modified

  14. Tricon hardware controller implementation of CANDU nuclear power plant shutdown system

    International Nuclear Information System (INIS)

    Zahedi, P.

    2007-01-01

    This paper introduces the implementation of logic functions associated with the shutdown systems of CANDU nuclear power plants. The experimental aspects of this work include development of control program embedded in shutdown systems of CANDU based NPPs. A physical test environment is designed to simulate the measurements of in-core flux detector (ICFD) and ion chamber (I/C) signals. The programmable logic used in this experimentation provides Triple Modular Redundant (TMR) architecture as well as a voting mechanism used upon execution of control program on each independent channel. (author)

  15. 77 FR 77074 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Science.gov (United States)

    2012-12-31

    ... records of the occurrence and duration of any startup, shutdown, or malfunction in the operation of an... units with a heat input capacity from fuels combusted in the unit of greater than 29 MW (100 million Btu...,544,313, which includes $155,639,313 in labor costs, $9,000,000 in capital/startup costs, and $25,905...

  16. Comparing the Entrepreneurial Ecosystems for Technology Startups in Bangalore and Hyderabad, India

    Directory of Open Access Journals (Sweden)

    M H Bala Subrahmanya

    2017-07-01

    Full Text Available Technology startups are gaining increasing attention from policy makers the world over because they are seen as a means of encouraging innovations, spurring the development of new products and services, and generating employment. Technology startups tend to thrive when inserted in a conducive entrepreneurial ecosystem. Therefore, ecosystem promotion is being given increasing policy support. However, the emergence and structure of entrepreneurial ecosystems for technology startups have hardly been traced and examined in detail. In India, Bangalore occupies a unique position in the startup world, and Hyderabad is fast emerging as one of the promising startup hubs in the country. Given this background, we set out to explore and examine the structure, evolution, and growth of ecosystems for technology startups in the context of Bangalore and Hyderabad. Both the ecosystems emerged due to the initial foundation laid in the form of government–industry–academia triple helix and their interactions leading to the emergence of a modern industrial cluster followed by an information technology and biotechnology cluster, which then led to R&D cluster serving both the cities. These three clusters together, gradually and steadily, facilitated an entrepreneurial ecosystem for technology startups to emerge. The ecosystem operates within the triple helix model and has a nucleus with two outer layers: i an inner layer of primary (indispensable factors and ii an outer layer of supplementary (secondary factors. Through the analysis of the experiences of Bangalore and Hyderabad and their ecosystem evolution, its structure, and components, we derive key lessons for others within and beyond India.

  17. Activity Based Startup Plan for Prototype Vertical Denitration Calciner

    International Nuclear Information System (INIS)

    SUTTER, C.S.

    1999-01-01

    Testing activation on the Prototype Vertical Denitration Calciner at PFP were suspended in January 1997 due to the hold on fissile material handling in the facility. The restart of testing activities will require a review through an activity based startup process based upon Integrated Safety Management (ISM) principles to verify readiness. The Activity Based Startup Plan for the Prototype vertical Denitration Calciner has been developed for this process

  18. Reserves for shutdown/dismantling and disposal in nuclear technology. Theses and recommendations on reform options

    International Nuclear Information System (INIS)

    Meyer, Bettina

    2012-01-01

    The study on reserves for shutdown, dismantling and disposal of nuclear facilities covers the following topics: cost for shutdown, dismantling and disposal and amount and transparency of nuclear reserves, solution by y stock regulated by public law for long-term liabilities, and improvement of the protection in the event of insolvency for the remaining EVU reserves for short- and intermediate-term liabilities. The appendix includes estimations and empirical values for the cost of shutdown and dismantling, estimation of disposal costs, and a summary of Swiss studies on dismantling and disposal and transfer to Germany.

  19. Fuel supply shutdown facility interim operational safety requirements

    International Nuclear Information System (INIS)

    Besser, R.L.; Brehm, J.R.; Benecke, M.W.; Remaize, J.A.

    1995-01-01

    These Interim Operational Safety Requirements (IOSR) for the Fuel Supply Shutdown (FSS) facility define acceptable conditions, safe boundaries, bases thereof, and management or administrative controls to ensure safe operation. The IOSRs apply to the fuel material storage buildings in various modes (operation, storage, surveillance)

  20. 300 Area fuel supply shutdown facility hazards assessment

    International Nuclear Information System (INIS)

    Campbell, L.R.

    1998-01-01

    This document establishes the technical basis in support of Emergency Planning activities for the 300 Area Fuel Supply Shutdown Facilities on the Hanford Site. Through this document, the technical basis for the development of facility specific Emergency Action Levels and Emergency Planning Zone, is demonstrated

  1. Consideration of a non-baked start-up of a synchrotron light source

    International Nuclear Information System (INIS)

    Hori, Y.; Kobayashi, M.

    1996-01-01

    Vacuum baking of large complex uhv devices, such as synchrotron light sources, requires both careful design and consideration of potential problems regarding the operation and maintenance of the device. Intense synchrotron irradiation can be utilized for degassing; it is indeed necessary to achieve the required operating pressure in most light sources. To examine a non-baked start-up, the outgassing of non-baked chambers by SR irradiation was measured. Also, a non-baked start-up was carried out at the Photon Factory ring. Both results demonstrate the feasibility of a non-baked start-up of a light source. The experiments and results are described, together with several other problems which must be solved for a non-baked start-up. (Author)

  2. Controlled shutdown of a fuel cell

    Science.gov (United States)

    Clingerman, Bruce J.; Keskula, Donald H.

    2002-01-01

    A method is provided for the shutdown of a fuel cell system to relieve system overpressure while maintaining air compressor operation, and corresponding vent valving and control arrangement. The method and venting arrangement are employed in a fuel cell system, for instance a vehicle propulsion system, comprising, in fluid communication, an air compressor having an outlet for providing air to the system, a combustor operative to provide combustor exhaust to the fuel processor.

  3. Simulating fission product transients via the history-based local-parameter methodology

    International Nuclear Information System (INIS)

    Jenkins, D.A.; Rouben, B.; Salvatore, M.

    1993-01-01

    This paper describes the fission-product-calculation capacity of the history-based local-parameter methodology for evaluating lattice properties for use in core-tracking calculations in CANDU reactors. In addition to taking into account the individual past history of each bundles flux/power level, fuel temperature, and coolant density and temperature that the bundle has seen during its stay in the core, the latest refinement of the history-based method provides the capability of fission-product-drivers. It allows the bundle-specific concentrations of the three basic groups of saturating fission products to be calculated in steady state or following a power transient, including long shutdowns. The new capability is illustrated by simulating the startup period following a typical long-shutdown, starting from a snapshot in the Point Lepreau operating history. 9 refs., 7 tabs

  4. The start-up processes of academic spin-offs and non-academic ventures

    OpenAIRE

    Roininen, Sari

    2006-01-01

    New and small firms are important for the national economic growth, and hence there is a growing interest among policy makers and researchers in understanding the start-up processes among new ventures in order to facilitate more new venture creations. Prior research addressing new ventures' start-up processes focus mainly on the individual behind the venture or different activities in the start-up process. The overall purpose of this study is to increase the understanding of new venture s...

  5. From Jam to Start-up

    DEFF Research Database (Denmark)

    Bering Kjæhr, Emil; Lyngbye Hvid Jensen, Jane; Schoenau-Fog, Henrik

    2015-01-01

    the foundation for new start-up companies. There are, however, an even larger group of very creative and innovative games and artifacts with great potential that go unpublished. This potentially leads to a loss of entrepreneurial opportunities and ultimately the jobs and careers such games could have fostered...

  6. Innovative start-ups and young entrepreneurs: Definition of venturem capital and findings from Switzerland

    Directory of Open Access Journals (Sweden)

    Simon Zaby

    2017-02-01

    Full Text Available This paper aims to investigate success factors of innovative start-up firms from the perspective of young start-up managers. Which key factors did they experience before and since the foundation of their company? The experience from the quite young Swiss start-up scene pro-vides important insights to entrepreneurs and policy-makers in emerging countries that cur-rently face the necessity of building up a start-up environment. One part of the data has been collected by the author, the other part originates from the Swiss Venture Capital Database (total sample size: 306. The results show a significant role of venture capital financing for the success of innovative start-ups. Interestingly, this is to some extent because the start-ups see various additional benefits from venture capitalists involved in their firm. Thus, the findings shed new light on a proper definition of venture capital that should not solely focus on the flow of funds.

  7. Self-actuated shutdown system for a commercial size LMFBR. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dupen, C.F.G.

    1978-08-01

    A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility and reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power.

  8. Prevention device for rapid reactor core shutdown in BWR type reactors

    International Nuclear Information System (INIS)

    Koshi, Yuji; Karatsu, Hiroyuki.

    1986-01-01

    Purpose: To surely prevent rapid shutdown of a nuclear reactor upon partial load interruption due to rapid increase in the system frequency. Constitution: If a partial load interruption greater than the sum of the turbine by-pass valve capacity and the load setting bias portion is applied in a BWR type power plant, the amount of main steams issued from the reactor is decreased, the thermal input/output balance of the reactor is lost, the reactor pressure is increased, the void is collapsed, the neutron fluxes are increased and the reactor power rises to generate rapid reactor shutdown. In view of the above, the turbine speed signal is compared with a speed setting value in a recycling flowrate control device and the recycling pump is controlled to decrease the recycling flowrate in order to compensate the increase in the neutron fluxes accompanying the reactor power up. In this way, transient changes in the reactor core pressure and the neutron fluxes are kept within a setting point for the rapid reactor shutdown operation thereby enabling to continue the plant operation. (Horiuchi, T.)

  9. Self-actuated shutdown system for a commercial size LMFBR. Final report

    International Nuclear Information System (INIS)

    Dupen, C.F.G.

    1978-08-01

    A Self-Actuated Shutdown System (SASS) is defined as a reactor shutdown system in which sensors, release mechanisms and neutron absorbers are contained entirely within the reactor core structure, where they respond inherently to abnormal local process conditions, by shutting down the reactor, independently of the plant protection system (PPS). It is argued that a SASS, having a response time similar to that of the PPS, would so reduce the already very low probability of a failure-to-scram event that costly design features, derived from core disruptive accident analysis, could be eliminated. However, the thrust of the report is the feasibility and reliability of the in-core SASS hardware to achieve sufficiently rapid shutdown. A number of transient overpower and transient undercooling-responsive systems were investigated leading to the selection of a primary candidate and a backup concept. During a transient undercooling event, the recommended device is triggered by the associated rate of change of pressure, whereas the alternate concept responds to the reduction in core pressure drop and requires calibration and adjustment by the operators to accommodate changes in reactor power

  10. Reload Startup Physics Tests for Tianwan Nuclear Power station

    International Nuclear Information System (INIS)

    Yang Xiaoqiang; Li Wenshuang; Li Youyi; Yao Jinguo; Li Zaipeng Jiangsu

    2010-01-01

    This paper briefly describes the test purposes, test items, test schedules and test equipment's for reload startup physics test's on Unit 1 and 2 of Tianwan Nuclear Power station. Then, an overview of the previous thrice tests and evaluations on the tests results are presented. In the end, the paper shows the development and work direction of optimization project for reload startup physics tests on Unit 1 and 2 of Tianwan Nuclear Power station. (Authors)

  11. Startup and mode competition in a 420 GHz gyrotron

    Science.gov (United States)

    Qixiang Zhao, A.; Sheng Yu, B.; Tianzhong Zhang, C.

    2017-09-01

    In the experiments of a 420 GHz second-harmonic gyrotron, it is found that the electron beam voltage and current ranges for single mode operation of TE17.4 are slightly narrower than those in the simulation. To explain this phenomenon, the startup scenario has been investigated with special emphasis on mode competition. The calculations indicate that the decreases of the operating ranges are caused by the voltage overshoot in the startup scenario.

  12. Site investigations, design, construction, operation, shutdown and surveillance of repositories for low- and intermediate-level radioactive wastes in rock cavities

    International Nuclear Information System (INIS)

    1984-01-01

    The report provides an overview and technical guidelines for considerations and for activities to be undertaken for safety assessment, site investigations, design, construction, operation, shutdown and surveillance of repositories for the disposal of low- and intermediate-level radioactive wastes in rock cavities. A generalized sequence of investigations is introduced which proceeds through region and site selection to the stage where the site is confirmed by detailed geoscientific investigations as being suitable for a waste repository. The different procedures and somewhat specific investigative needs with respect to existing mines are dealt with separately. General design, as well as specific requirements with respect to the different stages of design and construction, are dealt with. A review of activities related to the operational and post-operational stages of repositories in rock cavities is presented. The report describes in general terms the procedures related to different stages of disposal operation; also the conditions for shutdown together with essential shutdown and sealing activities and the related safety assessment requirements. Guidance is also given on the surveillance programme which will allow for inspection, testing, maintenance and security of a disposal facility during the operational phase, as well as for the post-operational stage for periods determined as necessary by the national authorities

  13. Effects of entrepreneurial orientation on start-up success: A gender perspective

    Directory of Open Access Journals (Sweden)

    Daisy Mui Hung Kee

    2018-06-01

    Full Text Available This paper examines the extent to which gender influences on the practice of Entrepreneurial Orien-tation (EO on Start-up Success. This study was conducted among Spin-off and Symbiosis Com-pany (SSC from all sectors in Peninsular Malaysia. Despite the remarkable research on EO and Start-up firms, there is a missing link on how gender provides different perspectives of EO practic-es among SSC, especially in Malaysia. A total of 120 SSC was chosen and the results show that EO was statistically related to Start-up Success and unveiled the magnitude of change that gender possesses in improving the relationship between EO practice and Start-up Success. The major implication of this study presents the unique contribution of gender in motivating SSC owners to engage in EO. Also, the difference of gender perceptions in business provides a variety of untapped opportunities in terms of entrepreneurial-related practices as different gender perceived different needs and capabilities. Future research is suggested to explore this phenomenon more extensively and develop a comprehensive model for the gender analysis. In brief, the discussion in this paper would help to strengthen the body of knowledge on Entrepreneurship and act as a future reference on SSC, EO, and Start-up Success.

  14. Double stage dry-wet-fermentation - start-up of a pilot biogas plant

    International Nuclear Information System (INIS)

    Buschmann, Jeannette; Busch, Gunter; Burkhardt, Marko

    2009-01-01

    The Brandenburg University of Technology (BTU) has developed a double stage dry-wet fermentation process for fast and safe anaerobic degradation. Originally designed for treatment of organic wastes, this process allows using a wide variety of solid biodegradable materials. The dividing of hydrolysis and methanation in this process, allows an optimization of the different steps of biogas generation separately. The main advantages of the process are the optimum process control, an extremely stable process operation and a high gas productivity and quality. Compared to conventional processes, the retention times within the percolation stage (hydrolysis) are reduced considerably. In cooperation with the engineering and consulting company GICON, the technology was qualified further to an industrial scale. In 2007 a pilot plant, and, simultaneously, an industrial plant were built by GICON based on this double stage technology. Based on practical experience from the operation of laboratory fermentation plants, the commissioning of the pilot plant was planned, controlled and monitored by our institution. The start-up of a biogas plant of this type focuses mainly on the inoculation the of methane reactor. The growth of microbial populations and generation of a stable biocenosis within the methane reactor is essential and affects the duration of starting period as well as the methanation efficiency a long time afterwards. This paper concerns with start-up of a pilot biogas plant and discusses particular occurrences and effects during this period. (author)

  15. Plant operational states analysis in low power and shutdown PSA

    International Nuclear Information System (INIS)

    He Jiandong; Qiu Yongping; Zhang Qinfang; An Hongzhen; Li Maolin

    2013-01-01

    The purpose of Plant Operational States (POS) analysis is to disperse the continuous and dynamic process of low power and shutdown operation, which is the basis of developing event tree models for accident sequence analysis. According to the design of a 300 MW Nuclear Power Plant Project, operating experience and procedures of the reference plant, a detailed POS analysis is carried out based on relative criteria. Then, several kinds of POS are obtained, and the duration of each POS is calculated according to the operation records of the reference plant. The POS analysis is an important element in low power and shutdown PSA. The methodology and contents provide reference for POS analysis. (authors)

  16. Three Mile Island Startup program and its contributions to plant performance

    International Nuclear Information System (INIS)

    Brill, R.A.; Barton, J.J.

    1976-01-01

    The General Public Utilities Service Corporation Startup Organization provided a specialized group for startup testing, coordination, and management of the Three Mile Island Unit No. 1 nuclear power plant. This organization conducted an extensive test program which contributed to Three Mile Island's high first year plant availability

  17. Using low frequency and intensity ultrasound to enhance start-up and operation performance of Anammox process inoculated with the conventional sludge.

    Science.gov (United States)

    Wang, Tao; Zhang, Diandian; Sun, Yating; Zhou, Shanshan; Li, Lin; Shao, Jingjing

    2018-04-01

    A lab-scale ultrasound enhancing Anammox reactor (R1) was established and irradiated once a week by ultrasound with the optimal parameter (frequency of 25 kHz, intensity of 0.2 W cm -2 and exposure time of 3 min) obtained by batch experiments. R1 and the controlled Anammox reactor (R2) without exposure to the ultrasound were operated in parallel. The start-up period of Anammox process (53 days) in R1 was shorter than that (61 days) in R2. The nitrogen loading-enhancing period (day 53-day 135) in R1 was also shorter than that (day 61-day 151) in R2. At the end of the nitrogen loading-enhancing period, NLR (0.76 kg N m -3  d -1 ) and NRR (0.68 kg N m -3  d -1 ) of R1 were both higher than NLR (0.66 kg N m -3  d -1 ) and NRR (0.56 kg N m -3  d -1 ) of R2. Moreover, The stability of Anammox process in R1 was better than that in R2. The results demonstrated that the periodical irradiation of ultrasound enhanced the start-up and operational performance of Anammox reactor. Microbial community analysis indicated that the ultrasound accelerated the microbial succession from some other bacteria to Anammox bacteria so that shorten the start-up period of Anammox process from the conventional activated sludge. It also indicated that the ultrasound strengthened the competitive advantage of Candidatus Kuenenia stuttgartiensis in Anammox bacteria of the mature sludge so as to enhance the nitrogen removal performance of the Anammox reactor under the operation condition of high nitrogen loading. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. >venture>: Support for Early Stage Start-ups and Potential Entrepreneurs.

    Science.gov (United States)

    Kauz, Lukas

    2014-12-01

    >venture>, the leading Swiss-wide business plan competition, is an ideal partner for young start-ups and entrepreneurs. For the upcoming tenth anniversary edition the competition will receive an update. Building upon a successful base of the past nine editions and equipped with contemporary networking events and more know-how transferring seminars, >venture> will fit even better into the Swiss start-up ecosystem.

  19. MECANISMOS DE GERAÇÃO DE EMPREENDIMENTOS: AS ACELERADORAS DE START-UPS NO BRASIL

    Directory of Open Access Journals (Sweden)

    Amanda Luiza Soares Silva

    2018-03-01

    Full Text Available Aceleradoras de Start-ups são consideradas mecanismos de geração de empreendimentos. O objetivo geral do estudo é caracterizar as aceleradoras participantes do Programa Nacional de Aceleração de Start-upsStart-up Brasil. Os principais resultados obtidos foram: perfil das start-ups selecionadas pelas aceleradoras, start-ups em áreas como educação, Tecnologia da Informação e Comunicação – TIC, saúde, economia criativa, entre outras; informações sobre a aceleradora, tais como locais de aceleração (Brasil, Estados Unidos da América – EUA e Suécia e quantidade de start-ups entre 3 e 130 em diversos estágios (pré-aceleradas, em aceleração, aceleradas e no portfólio; o investimento por start-up pode variar entre R$20.000,00 e R$3.000.000,00 e a participação acionária de 1%-40%, dependendo da aceleradora e de seus investidores internos e externos; e, as metodologias de aceleração possuem aspectos como mentoria, visitas técnicas em outros países, eventos, acesso a capital, networking e gestão de portfólios.

  20. 40 CFR 63.8266 - What definitions apply to this subpart?

    Science.gov (United States)

    2010-07-01

    ... data acquisition and availability requirements of this subpart, used to sample, condition (if... operating limit) or work practice standard in this subpart during startup, shutdown, or malfunction...

  1. Strategic Management: Business Model Canvas for Start-Up Company

    OpenAIRE

    Sonninen, Anna

    2016-01-01

    Thesis is written about development of Kakunpala as a Start-Up Company, because development processes and ideas are the key factors for future success of the company. The aim of this thesis is to understand Strategic Management of the Company and Development processes,by using the SWOT analysis before and after development and by applying Business Model Canvas template to the Start-Up Company, and by describing Customer Journey: what relations Kakunpala has with clients and its processes...

  2. Reactor shutdown device

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Kiyoshi; Aono, Hidehiro [Hitachi Ltd., Tokyo (Japan); Fujita, Kaoru; Ishikawa, Tsuyoshi

    1996-02-20

    The present invention concerns a reactor shutdown device of a LMFBR type reactor, and provides a magnetic circuit having a sharp changing property of holding force relative to temperature change. Namely, a magnetic bridge is attached to a portion of the magnetic circuit. Then, required conditions are satisfied. Alternatively, even if the temperature dependent change of magnetic saturation of a temperature sensing alloy itself is somewhat moderated, the holding force from an erroneous dropping preventive temperature to a separating temperature can be abruptly reduced while keeping the holding force at a temperature lower than the erroneous dropping preventive temperature. Provision of the magnetic bridge increases the temperature dependent change of the holding force of the entire magnetic circuit. As a result, margin for the design of the temperature sensing alloy is extended. Actual design is enabled, and the range for selecting the temperature sensing alloy can be enlarged. (I.S.).

  3. Reactor shutdown device

    International Nuclear Information System (INIS)

    Harada, Kiyoshi; Aono, Hidehiro; Fujita, Kaoru; Ishikawa, Tsuyoshi.

    1996-01-01

    The present invention concerns a reactor shutdown device of a LMFBR type reactor, and provides a magnetic circuit having a sharp changing property of holding force relative to temperature change. Namely, a magnetic bridge is attached to a portion of the magnetic circuit. Then, required conditions are satisfied. Alternatively, even if the temperature dependent change of magnetic saturation of a temperature sensing alloy itself is somewhat moderated, the holding force from an erroneous dropping preventive temperature to a separating temperature can be abruptly reduced while keeping the holding force at a temperature lower than the erroneous dropping preventive temperature. Provision of the magnetic bridge increases the temperature dependent change of the holding force of the entire magnetic circuit. As a result, margin for the design of the temperature sensing alloy is extended. Actual design is enabled, and the range for selecting the temperature sensing alloy can be enlarged. (I.S.)

  4. Safe shutdown analysis for submerged equipment inside containment

    International Nuclear Information System (INIS)

    Song, Dong Soo; Lee, Seung Chan; Yoon, Duk Joo; Ha, Sang Jun

    2017-01-01

    The purpose of the paper is to analyze internal flooding effects on the submerged safety-related components inside containment building. Safe shutdown analysis has been performed based on the criteria, assumptions and guideline provided in ANSI/ANS-56.11-1988 and ANSI/ANS-58.11-1988. Flooding can be postulated from a failure of several systems located inside the containment. Loss of coolant accident (LOCA), Feed water line break (FWLB), and other pipe breaks/cracks are assumed. The worst case flooding scenario is a large break LOCA. The maximum flood level for a large break LOCA is calculated based on the combined inventory of the reactor coolant system, the three accumulators, the boron injection tank (BIT), the chemical additive tank (CAT), and the refueling water storage tank (RWST) flooding the containment. The maximum flood level that could occur from all of the water which is available in containment is 2.3 m from the base elevation. A detailed flooding analysis for the components has been performed to demonstrate that internal flooding resulting from a postulated initiating event does not cause the loss of equipment required to achieve and maintain safe shutdown of the plant, emergency core cooling capability, or equipment whose failure could result in unacceptable offsite radiological consequences. The flood height can be calculated as h = (dh/dt) x (t-t 0 ) + h 0 , where h = time dependent flood height and subscript 0 means the initial value and height slope dh/dt. In summary, the submerged components inside containment are acceptable because they complete the mission of safety injection (SI) prior to submeregency or have no safe shutdown function including containment isolation during an accident. (author)

  5. Lean and global technology start-ups

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager; Zijdemans, Erik

    2015-01-01

    In this paper the authors introduce the concept of Lean Global Start-up (LGS) as a way of emphasizing the impossibility for new technology start-ups to deal separately with business development, innovation and early internationalization. For a newly established technology firm the task of being...... global and innovative at the same time should be seen as one process. The paper has two components – an introductory conceptual part and an empirical part that should be considered as basis for the preliminary validation of the conceptual insights. The research sample includes six firms – three from...... Canada and three from Denmark. The firms have had significant problems with the complexity, uncertainties and risks of being innovative on a global scale. They have however found ways of addressing these problems by a disciplined knowledge sharing and IP protection strategy and the efficient use...

  6. Smart or Diverse Start-up Teams?

    DEFF Research Database (Denmark)

    Hoogendoorn, Sander; Parker, Simon C.; Van Praag, Mirjam

    2017-01-01

    This paper explores the relationship between cognitive abilities and team performance in a start-up setting. We argue that performance in this setting hinges on three tasks: opportunity recognition, problem solving, and implementation. We theorize that cognitive ability at the individual level has...... others can be assigned to tasks that impose a greater cognitive load (problem solving or opportunity recognition). We present the results of a field experiment in which 573 students in 49 teams started up and managed real companies. We ensured exogenous variation in—otherwise random—team composition...... by assigning students to teams based on their measured cognitive abilities. Each team performed a variety of tasks, often involving complex decision making. The key result of the experiment is that the performance of start-up teams first increases and then decreases with ability dispersion. Strikingly, average...

  7. The management of large cabling campaigns during the Long Shutdown 1 of LHC

    CERN Document Server

    Meroli, Stefano; Formenti, Fabio; Frans, Marten; Guillaume, Jean Claude; Ricci, Daniel

    2014-01-01

    The Large Hadron Collider at CERN entered into its first 18 month-long shutdown period in February 2013. During this period the entire CERN accelerator complex will undergo major consolidation and upgrade works, preparing the machines for LHC operation at nominal energy (7 TeV/beam). One of the most challenging activities concerns the cabling infrastructure (copper and optical fibre cables) serving the CERN data acquisition, networking and control systems. About 1000 kilometres of cables, distributed in different machine areas, will be installed, representing an investment of about 15 MCHF. This implies an extraordinary challenge in terms of project management, including resource and activity planning, work execution and quality control. The preparation phase of this project started well before its implementation, by defining technical solutions and setting financial plans for staff recruitment and material supply. Enhanced task coordination was further implemented by deploying selected competences to form a ...

  8. Assessment of the plasma start-up in Wendelstein 7-X with neutral beam injection

    International Nuclear Information System (INIS)

    Gradic, D.; Dinklage, A.; Brakel, R.; McNeely, P.; Rust, N.; Wolf, R.; Osakabe, M.

    2015-01-01

    Plasma start-up by neutral beam injection was investigated for stellarators. A zero-dimensional collisional model was extended to evaluate the temporal evolution of the plasma start-up in a confining toroidal magnetic field. Inclusion of different beam energy components indicated a substantial effect due to the energy dependence of beam–gas collisions. Additional collision processes and particle equations were considered to simulate the plasma start-up in helium–hydrogen mixtures. The isotope effect between operation with hydrogen and deuterium beams was also investigated. As a major objective the conditions necessary for a plasma start-up with neutral beams in W7-X have been examined. The assessed beam configuration in W7-X was found not to allow plasma start-up by neutral beam injection alone. The model has been validated for experimental data from W7-AS and Large Helical Device. Quantitative predictions of this study show that the ratio of the beam–plasma interaction length and the plasma volume is an essential quantity for the successful plasma start-up with neutral beams. (paper)

  9. Reliability assessment of PARR-1 renovated I and C system startup channel-b

    Energy Technology Data Exchange (ETDEWEB)

    Qamar, M.A.; Habib, M.A.; Iqbal, M.

    1991-11-20

    The report covers the reliability assessment of the startup channel-B of the PARR-1 renovated instrumentation and Control. For startup channel-A, a separate report (DNSRP-10(7)/88) was prepared in 1988. As the modules are of different origins in both the channels, a separate calculation was necessary. In the report the overall unreliability of the startup channel has been calculated by considering 1 out of 2 operation mode. In the assessment, the reliability calculations for the channel has been performed using similar assumptions as used in the authors' report on startup channel-A. For the analysis the Component Count Method (CCM) was applied. Comparison of results for channel-A and channel-B were made.

  10. An analysis of reactivity prediction during the reactor start-up process

    International Nuclear Information System (INIS)

    Bajgl, Josef; Krysl, Vaclav; Svarny, Jiri

    2015-01-01

    The different VVER-440 core fuel loadings subcriticality evaluations are performed during the start-up process by boron dilution or control assembly withdrawn by macrocode MOBY-DICK calculations. The dynamic reactivity and quasicritical reactivity are compared and sensitivity of reactivity prediction at the low boundary of start-up interval (ρ = -0,01) has been provided on the basis of different modelling of ionization chamber (IC) response calculation. Special attention is paid to the impact of power distribution and spontaneous fission distribution form factor on IC response correction during control assembly movement. Precision and robustness of different corrections of IC signal processing in real core start-up processed IC signals was evaluated.

  11. Accelerating Research Innovation by Adopting the Lean Startup Paradigm

    Directory of Open Access Journals (Sweden)

    Kaisa Still

    2017-05-01

    Full Text Available Converting scientific expertise into marketable products and services is playing an increasingly important role in the launching of new ventures, the growth of existing firms, and the creation of new jobs. In this article, we explore how the lean startup paradigm, which validates the market for a product with a business model that can sustain subsequent scaling, has led to a new process model to accelerate innovation. We then apply this paradigm to the context of research at universities and other research organizations. The article is based on the assumption that the organizational context matters, and it shows how a deeper understanding of the research context could enable an acceleration of the innovation process. We complement theoretical examples with a case example from VTT Technical Research Institute of Finland. Our findings show that many of the concepts from early-acceleration phases – and the lean startup paradigm – can also be relevant in innovation discussions within the research context. However, the phase of value-proposition discovery is less adequately addressed, and that of growth discovery, with its emphasis on building on a scalable, sustainable business does not seem to be addressed with the presented innovation approaches from the research context. Hence, the entrepreneurial activities at the research context differ from those in startups and internal startups in established organizations.

  12. Analysis of activation and shutdown contact dose rate for EAST neutral beam port

    Science.gov (United States)

    Chen, Yuqing; Wang, Ji; Zhong, Guoqiang; Li, Jun; Wang, Jinfang; Xie, Yahong; Wu, Bin; Hu, Chundong

    2017-12-01

    For the safe operation and maintenance of neutral beam injector (NBI), specific activity and shutdown contact dose rate of the sample material SS316 are estimated around the experimental advanced superconducting tokamak (EAST) neutral beam port. Firstly, the neutron emission intensity is calculated by TRANSP code while the neutral beam is co-injected to EAST. Secondly, the neutron activation and shutdown contact dose rates for the neutral beam sample materials SS316 are derived by the Monte Carlo code MCNP and the inventory code FISPACT-2007. The simulations indicate that the primary radioactive nuclides of SS316 are 58Co and 54Mn. The peak contact dose rate is 8.52 × 10-6 Sv/h after EAST shutdown one second. That is under the International Thermonuclear Experimental Reactor (ITER) design values 1 × 10-5 Sv/h.

  13. Predictive modelling for startup and investor relationship based on crowdfunding platform data

    Science.gov (United States)

    Alamsyah, Andry; Buono Asto Nugroho, Tri

    2018-03-01

    Crowdfunding platform is a place where startup shows off publicly their idea for the purpose to get their project funded. Crowdfunding platform such as Kickstarter are becoming popular today, it provides the efficient way for startup to get funded without liabilities, it also provides variety project category that can be participated. There is an available safety procedure to ensure achievable low-risk environment. The startup promoted project must accomplish their funded goal target. If they fail to reach the target, then there is no investment activity take place. It motivates startup to be more active to promote or disseminate their project idea and it also protect investor from losing money. The study objective is to predict the successfulness of proposed project and mapping investor trend using data mining framework. To achieve the objective, we proposed 3 models. First model is to predict whether a project is going to be successful or failed using K-Nearest Neighbour (KNN). Second model is to predict the number of successful project using Artificial Neural Network (ANN). Third model is to map the trend of investor in investing the project using K-Means clustering algorithm. KNN gives 99.04% model accuracy, while ANN best configuration gives 16-14-1 neuron layers and 0.2 learning rate, and K-Means gives 6 best separation clusters. The results of those models can help startup or investor to make decision regarding startup investment.

  14. Help Wanted: Exploring the Value of Entrepreneurial Mentoring at Start-Up

    Science.gov (United States)

    Brodie, Jacqueline; Van Saane, Sebastiaan Huib; Osowska, Renata

    2017-01-01

    The purpose of the research presented in this article was to investigate the added value of mentoring for entrepreneurs during the start-up phase. This small-scale exploratory research focused on five start-up entrepreneurs in Scotland to determine the entrepreneurs' perceptions regarding the "added" value of their mentoring support. To…

  15. Startup of a Joule-heated glass melter with a graphite slurry

    International Nuclear Information System (INIS)

    Allen, T.L.; Porter, M.A.; Routt, K.R.

    1984-01-01

    Startup of a Joule-heated glass melter using a graphite slurry as a conducting medium was demonstrated. This technique can be used for the initial startup and for the restart of a melter used for vitrifying high-level radioactive waste. Theory, physical property data, and a demonstration test are reported

  16. Navigating the Interface between Design Education and Fashion Business Start-up

    Science.gov (United States)

    Mills, Colleen E.

    2012-01-01

    Purpose: The purpose of this paper is to address the interface between design education and business start-up in the designer fashion industry (DFI) and provide a new framework for reflecting on ways to improve design education and graduates' business start-up preparedness. Design/methodology/approach: This interpretive study employed…

  17. Effects of shutdown chemistry on steam generator radiation levels at Point Beach Unit 2. Interim report

    International Nuclear Information System (INIS)

    Kormuth, J.W.

    1982-05-01

    A refueling shutdown chemistry test was conducted at a PWR, Point Beach Unit 2. The objective was to yield reactor coolant chemistry data during the cooldown/shutdown process which might establish a relationship between shutdown chemistry and its effects on steam generator radiation fields. Of particular concern were the effects of the presence of hydrogen in the coolant as contrasted to an oxygenated coolant. Analysis of reactor coolant samples showed a rapid soluble release (spike) in Co-58, Co-60, and nickel caused by oxygenation of the coolant. The measurement of radioisotope specific activities indicates that the material undergoing dissolution during the shutdown originated from different sources which had varying histories of activation. The test program developed no data which would support theories that oxygenation of the coolant while the steam generators are full of water contributes to increased steam generator radiation levels

  18. Building Dynamic Capabilities in Web Startups: An Empirical Study of Norwegian Web Startups

    OpenAIRE

    Sahlen, Martin Abelson; Gran-Jansen, Sigurd; Rygh, Mathias

    2014-01-01

    Purpose: This thesis explores how web startups operating in a crowded, fast-moving and highly competitive marketplace can gain competitive advantage through building dynamic capabilities and what these capabilities consist of. Design/methodology/approach: Firstly, insight was obtained through reviewing key themes within classic resource based theory and entrepreneurship theory. Newer empirical research on entrepreneurial success factors, as well as popular science and advice given by expert w...

  19. GUERRILLA MARKETING : A creative marketing method for start-ups

    OpenAIRE

    Zujewska, Barbara

    2014-01-01

    The objective of this thesis work was to introduce guerrilla marketing as a valuable marketing method for small and medium size startup companies. The thesis presents the theoretical studies on the subject based on literature and case studies. The practical use of the theory is demonstrated in the marketing plan based on guerrilla marketing approach. The marketing plan was written based on the example of an existing startup company, mCASH. The company is located in Oslo, Norway. The thesis...

  20. Power in a startup's relationships with its established partners : Interactions between structural and behavioural power

    NARCIS (Netherlands)

    Oukes, Tamara; von Raesfeld Meijer, Ariane; Groen, Aard

    2017-01-01

    Power plays a key role in the relationships between startups and established organisations. Yet researchers have devoted little attention to the startup's perspective on power in such relationships. To study startups' view on power, a useful starting point is their structural power, but this also

  1. The Impact of Digitalization on the Speed of Internationalization of Lean Global Startups

    Directory of Open Access Journals (Sweden)

    Michael Neubert

    2018-05-01

    Full Text Available Lean global startups need to internationalize early and fast. The digitalization of new foreign market development helps them to more efficiently identify new market opportunities in global markets. With this approach, they are saving resources while developing the most attractive markets. This article examines how lean global startups develop new foreign markets more rapidly due to digitalization. Thus, the aim is to understand the impact of digitalization on speed of internationalization of lean global startups. The study addresses a gap in the scholarly literature and a practical need to evaluate new foreign markets and business opportunities more quickly and more regularly and to understand what helps lean global startups react more quickly to opportunities and threats with respect to changing market attractiveness. Furthermore, it outlines why and how digitalization is important throughout the internationalization process. The research followed a multiple case-study design using different sources of evidence, including 73 interviews with senior managers of lean global startups. The findings reveal that digitalization allows lean global startups to increase decision-making efficiency and to optimize strategies and processes for evaluating international markets. The findings suggest that lean global startups can benefit from the use of digital technologies by applying a more efficient foreign market development process with regular reviews and a reduced workflow, by faster mediation between local market realities and strategic goals, by analyzing all foreign markets instead of just a sample of them, and by optimizing decision-making processes including the ability to make long-term, strategic decisions due to better market information.

  2. Start-up Success in a Small Island State: A Study among Entrepreneurs in Malta

    Directory of Open Access Journals (Sweden)

    Leonie Baldacchino

    2008-05-01

    Full Text Available This study focuses on entrepreneurs in the small island state of Malta and investigates whether starting up and running an enterprise is facilitated or hindered by being in a small island environment. Specifically it asks (1 whether being on a small island, on the periphery of a major market facilitates or hinders entrepreneurship and start-up success; (2 whether Malta’s cultural context and enterprise environment affect entrepreneurship and start-up success; (3 what the key success factors among Maltese start-ups are; and (4 how are creativity and innovation reflected in Maltese start-ups. Qualitative research among 13 start-ups is supported by telephone-based research among a sample of 90 respondents. Findings contribute to the pool of business expertise and context-specific information from small island states that is often missing from the international literature.

  3. Preliminary review of critical shutdown heat removal items for common cause failure susceptibility on LMFBR's. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Allard, L.T.; Elerath, J.G.

    1976-02-01

    This document presents a common cause failure analysis for Critical LMFBR Shutdown Heat Removal Systems. The report is intended to outline a systematic approach to defining areas with significant potential for common causes of failure, and ultimately provide inputs to the reliability prediction model. A preliminary evaluation of postulatd single initiating causes resulting in multiple failures of LMFBR-SHRS items is presented in Appendix C. This document will be periodically updated to reflect new information and activity.

  4. First physical start-up for the first pulsed reactor in China

    International Nuclear Information System (INIS)

    Huang Wenlou; Tan Rilin; Xie Yuqi; Chai Songshan; Li Yingfa; He Qianming; Zhou Bin

    1993-01-01

    The characteristics and the test results of initial loading fuel and first physical start-up for the first pulsed reactor in China (PRC-1) are described. Safe measure to ensure safety of first physical start-up are also described. The experiments show that performances of PRC-1 are in accord with design requirements

  5. Leadership toward Creativity in Virtual Work in a Start-Up Context

    Science.gov (United States)

    Humala, Iris Annukka

    2015-01-01

    Purpose: This paper aims to better understand how to lead toward creativity in virtual work in a start-up context. Design/methodology/approach: The study investigates the participants' experiences about the learning challenges in leadership toward creativity in virtual work in a start-up company and the meanings attributed to their experiences,…

  6. Solenoid-free plasma startup in NSTX using transient CHI

    International Nuclear Information System (INIS)

    Raman, R.; Jarboe, T.R.; Nelson, B.A.; Mueller, D.; Bell, M.G.; Bell, R.; Gates, D.; Gerhardt, S.; Hosea, J.; Kaita, R.; Kugel, H.; LeBlanc, B.; Menard, J.; Ono, M.; Paul, S.; Roquemore, L.; Maingi, R.; Maqueda, R.; Nagata, M.; Sabbagh, S.

    2009-01-01

    Experiments in NSTX have now demonstrated the coupling of toroidal plasmas produced by the technique of coaxial helicity injection (CHI) to inductive sustainment and ramp-up of the toroidal plasma current. In these discharges, the central Ohmic transformer was used to apply an inductive loop voltage to discharges with a toroidal current of about 100 kA created by CHI. The coupled discharges have ramped up to >700 kA and transitioned into an H-mode demonstrating compatibility of this startup method with conventional operation. The electron temperature in the coupled discharges reached over 800 eV and the resulting plasma had low inductance, which is preferred for long-pulse high-performance discharges. These results from NSTX in combination with the previously obtained record 160 kA non-inductively generated startup currents in an ST or tokamak in NSTX demonstrate that CHI is a viable solenoid-free plasma startup method for future STs and tokamaks.

  7. Inherently safe SNR shutdown system with Curie point controlled sensor/switch unit

    International Nuclear Information System (INIS)

    Mueller, K.; Norajitra, P.; Reiser, H.

    1987-02-01

    Inherent shutdown due to increase in the sodium temperature at the core outlet is triggered by interruption of the current supply to the electromagnet coupling of absorber elements via curie point controlled sensor/switch units. These switches are arranged above suitable fuel element positions and spatially independent of the shutdown elements. Compared with other similar systems very short response times are achieved. A prototype switch unit has already undergone extensive testing. These tests have confirmed that switching takes place in a very narrow temperature range. (orig./HP) [de

  8. Mathematical modeling and analysis of heat pipe start-up from the frozen state

    International Nuclear Information System (INIS)

    Jang, J.H.; Faghri, A.; Chang, W.S.; Mahefkey, E.T.

    1989-08-01

    The start-up process of a frozen heat pipe is described and a complete mathematical model for the start-up of the frozen heat pipe is developed based on the existing experimental data, which is simplified and solved numerically. The two-dimensional transient model for the wall and wick is coupled with the one-dimensional transient model for the vapor flow when vaporization and condensation occur at the interface. A parametric study is performed to examine the effect of the boundary specification at the surface of the outer wall on the successful start-up from the frozen state. For successful start-up, the boundary specification at the outer wall surface must melt the working substance in the condenser before dry-out takes place in the evaporator

  9. Urbanization and start-up rates in different geographies: Belgium, the Netherlands and Sweden

    OpenAIRE

    Hans, Lianne; Koster, Sierdjan

    2017-01-01

    This study addresses the mediating role of settlement patterns in the relationship between urbanization and start-up activity. Places do not operate in a vacuum and to understand the effect of 'own' density on start-up patterns, we need to account for the urban spillovers or borrowed size that they may experience from other places nearby. The results can explain the empirical ambiguity in the relationship between urbanization and start-up patterns: the relationship between urbanization and st...

  10. The Impact of Start-up Grants on Firm Performance in Estonia

    Directory of Open Access Journals (Sweden)

    Siret Vildo

    2013-01-01

    Full Text Available As in economic theory start-up enterprises have been seen as important sources of growth, the government support measures to enterprises have been a common practice around the world for decades. As the governmental support to enterprises is often of a considerable amount of money there is a need to assess its efficiency. In the present article we study the impact of Estonian start-up grants distributed in 2002 and 2003 on various indicators of firm performance with econometric methods, namely propensity score matching. We use the data from the Estonian Business Register in order to study the impact of start-up grants on various economic indicators like the number of employees, turnover, equity, fixed assets and firm survival. The results showed that the start-up grants proved to affect positively the number of employed people and turnover, yet the impact on productivity was negative. One implication of the study is that it is difficult to achieve different goals to the same extent with a single governmental grant

  11. Start-up of plasma current by electron Bernstein wave

    International Nuclear Information System (INIS)

    Maekawa, Takashi; Tanaka, Hitoshi; Uehide, Masaki

    2009-01-01

    Electron cyclotron current drive by electron Bernstein (EB) waves for the start-up and ramp-up of toroidal plasma current with no central solenoid in tokamaks is discussed. It is shown that high N// EB waves have ability to ramp-up the current against the counter voltage from self-induction, where N// is the parallel refractive index to the magnetic field, and they are especially suitable for initial current start-up phase where the bulk electron temperature is low enough to ensure high N// EB waves. (author)

  12. Female Hires and the Success of Start-up Firms

    OpenAIRE

    Weber, Andrea; Zulehner, Christine

    2009-01-01

    In this paper we investigate the relationship between females among the first hires of start-up companies and business success. Our results show that firms with female first hires have a higher share of female workers at the end of the first year after entry. Further, we find that firms with female first hires are more successful and stay longer in the market. We conclude that our results support the hypothesis that gender-diversity in leading positions is an advantage for start-up firms.

  13. Seismic design margin evaluation of systems and equipment required for safe shutdown of North Anna, Units 1 and 2, following an SSE (safe-shutdown earthquake) event. Technical report

    International Nuclear Information System (INIS)

    Desai, K.D.

    1981-06-01

    The Advisory Committee on Reactor Safeguards recommended that the NRC staff review in detail the capability and available seismic design margin of fluid systems and equipment used in North Anna, Units 1 and 2 to achieve safe shutdown following a site-design safe-shutdown earthquake (SSE). The staff conducted a series of plant visits and meetings with the licensee to view and discuss the seismic design methodology used for systems, equipment and their supports. The report is a description and evaluation of the seismic design criteria, design conservatisms and seismic design margin for North Anna, Units 1 and 2

  14. Substantiation of operation limits of reactivity insertion during WWER-1000 reactors start-up; Obosnovanie ehkspluatatsionnykh predelov vvoda reaktivnosti pri puske reaktorov WWER-1000

    Energy Technology Data Exchange (ETDEWEB)

    Boev, I; Sabitov, A; Sal` kov, V; Sudarev, O; Yakovlev, A [ATOMTECHENERGO RF, Novovoronezh (Russian Federation)

    1996-12-31

    The methods and programmes used to define the tolerable rate of reactivity insertion during WWER-1000 start-up are presented. They include calculation of the neutron source power in the core during the sub-critical stage and calculation of the relative neutron density and reactor period during the critical stage. The need for optimisation and regulation of tolerable rates is discussed along with the tool parameters affecting the reactivity during start-up. The possibility of increasing the feed rate of pure condensate into the first loop during the time needed to reach critical stage is justified. 4 refs., 3 tabs.

  15. Tokamak startup with electron cyclotron heating

    International Nuclear Information System (INIS)

    Holly, D.J.; Prager, S.C.; Shepard, D.A.; Sprott, J.C.

    1980-04-01

    Experiments are described in which the startup voltage in a tokamak is reduced by approx. 60% by the use of a modest amount of electron cyclotron resonance heating power for preionization. A 50% reduction in volt-second requirement and impurity reflux are also observed

  16. Tokamak startup with electron cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Holly, D J; Prager, S C; Shepard, D A; Sprott, J C

    1980-04-01

    Experiments are described in which the startup voltage in a tokamak is reduced by approx. 60% by the use of a modest amount of electron cyclotron resonance heating power for preionization. A 50% reduction in volt-second requirement and impurity reflux are also observed.

  17. Rapid establishment of thermophilic anaerobic microbial community during the one-step startup of thermophilic anaerobic digestion from a mesophilic digester.

    Science.gov (United States)

    Tian, Zhe; Zhang, Yu; Li, Yuyou; Chi, Yongzhi; Yang, Min

    2015-02-01

    The purpose of this study was to explore how fast the thermophilic anaerobic microbial community could be established during the one-step startup of thermophilic anaerobic digestion from a mesophilic digester. Stable thermophilic anaerobic digestion was achieved within 20 days from a mesophilic digester treating sewage sludge by adopting the one-step startup strategy. The succession of archaeal and bacterial populations over a period of 60 days after the temperature increment was followed by using 454-pyrosequencing and quantitative PCR. After the increase of temperature, thermophilic methanogenic community was established within 11 days, which was characterized by the fast colonization of Methanosarcina thermophila and two hydrogenotrophic methanogens (Methanothermobacter spp. and Methanoculleus spp.). At the same time, the bacterial community was dominated by Fervidobacterium, whose relative abundance rapidly increased from 0 to 28.52 % in 18 days, followed by other potential thermophilic genera, such as Clostridium, Coprothermobacter, Anaerobaculum and EM3. The above result demonstrated that the one-step startup strategy could allow the rapid establishment of the thermophilic anaerobic microbial community. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Study on ECH-assisted start-up using trapped particle configuration in KSTAR and application to ITER

    Science.gov (United States)

    Lee, Jeongwon; Kim, Jayhyun; An, YoungHwa; Yoo, Min-Gu; Hwang, Y. S.; Na, Yong-Su

    2017-12-01

    ECH-assisted start-up using trapped particle configuration (TPC) is firstly studied in a superconducting, conventional tokamak, KSTAR. First, improved and efficient start-up using TPC than conventional field null configuration (FNC) is achieved by enhanced pre-ionization plasma quality. TPC shows the broader operation window in terms of the poloidal field quality and the deuterium prefill pressure than that of FNC. Surprisingly the particle trapping enhances the plasma start-up performance even with much lower particle trapping ratio than that of spherical torus. Reliability of TPC with low trapping ratio is investigated by 0D plasma evolution code, TECHP0D. Second, the characteristics of TPC start-up are explored with experiments and modellings. Two kind of start-up failure conditions are identified by the magnetic pitch and prefill pressure scan experiments: (i) low ionization rate; and (ii) low density condition. These experimental observation has consistency with TECHP0D modeling result. Finally, reliable ITER-relevant low toroidal electric field start-up using TPC is achieved with drastically improved success rate of start-up in KSTAR. In this experiments, validity of the ITER-like toroidally inclined ECH/ECCD injection is also expected. Time dependent ITER start-up scenario using TPC is proposed and the superiority of it than FNC is discussed.

  19. An Integrated Start-Up Method for Pumped Storage Units Based on a Novel Artificial Sheep Algorithm

    Directory of Open Access Journals (Sweden)

    Zanbin Wang

    2018-01-01

    Full Text Available Pumped storage units (PSUs are an important storage tool for power systems containing large-scale renewable energy, and the merit of rapid start-up enable PSUs to modulate and stabilize the power system. In this paper, PSU start-up strategies have been studied and a new integrated start-up method has been proposed for the purpose of achieving swift and smooth start-up. A two-phase closed-loop startup strategy, composed of switching Proportion Integration (PI and Proportion Integration Differentiation (PID controller is designed, and an integrated optimization scheme is proposed for a synchronous optimization of the parameters in the strategy. To enhance the optimization performance, a novel meta-heuristic called Artificial Sheep Algorithm (ASA is proposed and applied to solve the optimization task after a sufficient verification with seven popular meta-heuristic algorithms and 13 typical benchmark functions. Simulation model has been built for a China’s PSU and comparative experiments are conducted to evaluate the proposed integrated method. Results show that the start-up performance could be significantly improved on both indices on overshoot and start-up, and up to 34%-time consumption has been reduced under different working condition. The significant improvements on start-up of PSU is interesting and meaning for further application on real unit.

  20. Start-up emissions from residential down-draught wood log boilers

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, E. (Luleaa Univ. of Technology (Sweden). Energy Technology Centre in Piteaa), Email: esbjorn.pettersson@ltu.se

    2009-07-01

    Start-up emissions can be substantial and even dominating in real use. There are few published investigations regarding the relative importance of different parameters on the start-up emissions. It has though recently been stated that for down-draught boilers, best results are achieved if the wood charge is ignited fairly close to the secondary chamber. The objective of the experimental work was to evaluate the effect of different fuel and design parameters on the start-up emissions, using experimental design which enables a direct comparison between different parameters, using three levels of preheating of secondary air, electric preheating of primary air, different moisture and size of the start wood as well as different amounts of birch bark, which was used to spread the fire during the start. The boiler did not use a bypass damper and the full fuel charge was added before igniting the start wood through an ignition door situated slightly above the grate. The only significant results for the four parameters were that smaller and drier start wood gave lower start-up emissions. Extra amount of birch bark gave the same result. The most important parameters are the fuel parameters, which mean that the result is generally applicable. (orig.)