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Sample records for reserve shutdown system

  1. 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)

  2. Control rod shutdown system

    International Nuclear Information System (INIS)

    Miyamoto, Yoshiyuki; Higashigawa, Yuichi.

    1996-01-01

    The present invention provides a control rod terminating system in a BWR type nuclear power plant, which stops an induction electric motor as rapidly as possible to terminate the control rods. Namely, the control rod stopping system controls reactor power by inserting/withdrawing control rods into a reactor by driving them by the induction electric motor. The system is provided with a control device for controlling the control rods and a control device for controlling the braking device. The control device outputs a braking operation signal for actuating the braking device during operation of the control rods to stop the operation of the control rods. Further, the braking device has at least two kinds of breaks, namely, a first and a second brakes. The two kinds of brakes are actuated by receiving the brake operation signals at different timings. The brake device is used also for keeping the control rods after the stopping. Even if a stopping torque of each of the breaks is small, different two kinds of brakes are operated at different timings thereby capable of obtaining a large stopping torque as a total. (I.S.)

  3. 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

  4. 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

  5. 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

  6. 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.

  7. Self-actuating reactor shutdown system

    Science.gov (United States)

    Barrus, Donald M.; Brummond, Willian A; Peterson, Leslie F.

    1988-01-01

    A control system for the automatic or self-actuated shutdown or "scram" of a nuclear reactor. The system is capable of initiating scram insertion by a signal from the plant protection system or by independent action directly sensing reactor conditions of low-flow or over-power. Self-actuation due to a loss of reactor coolant flow results from a decrease of pressure differential between the upper and lower ends of an absorber element. When the force due to this differential falls below the weight of the element, the element will fall by gravitational force to scram the reactor. Self-actuation due to high neutron flux is accomplished via a valve controlled by an electromagnet and a thermionic diode. In a reactor over-power, the diode will be heated to a change of state causing the electromagnet to be shorted thereby actuating the valve which provides the changed flow and pressure conditions required for scramming the absorber element.

  8. 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)

  9. 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)

  10. 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

  11. 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

  12. FPGA Implementation of the stepwise shutdown system

    International Nuclear Information System (INIS)

    Lotjonen, L.

    2012-01-01

    This report elaborates the design process of applications for field-programmable gate array (FPGA) devices. Brief introductions to EPGA technology and the design process are first given and then the design phases are walked through with the aid of a case study. FPGA is a programmable logic device that is programmed by the customer rather than the manufacturer. They are also usually re-programmable which enables updating their programming and otherwise modifying the design. There are also one-time programmable FPGAs that can be used when security issues require it. FPGA is said to be 'hardware designed like software', which means that the design process resembles software development but the end-product is considered a hardware application because the execution of the functions is entirely different from a microprocessor. This duality can give both the flexibility of software and the reliability of hardware. The FPGA design and verification and validation (V and V) methods for NPP safety systems have not yet matured because the technology is rather new in the field. Software development methods and standards can be used to some extent but the hardware aspects bring new challenges that cannot be tackled using purely software methods. International efforts are being made to development formal and consistent design and V and V methodology regulations for FPGA devices. A preventive safety function called Stepwise Shutdown System (SWS) was implemented on an Actel M1 IGLOO field-programmable gate array (FPGA) device. SWS is used to drive a process into a normal state if the process measurements deviate from the desired operating values. This can happen in case of process disturbances. The SWS implementation process from the requirements to the functional device is elaborated. The design is tested via simulation and hardware testing. The case study is to be further expanded as a part of a master's thesis. (orig.)

  13. FPGA Implementation of the stepwise shutdown system

    Energy Technology Data Exchange (ETDEWEB)

    Lotjonen, L.

    2012-07-01

    This report elaborates the design process of applications for field-programmable gate array (FPGA) devices. Brief introductions to EPGA technology and the design process are first given and then the design phases are walked through with the aid of a case study. FPGA is a programmable logic device that is programmed by the customer rather than the manufacturer. They are also usually re-programmable which enables updating their programming and otherwise modifying the design. There are also one-time programmable FPGAs that can be used when security issues require it. FPGA is said to be 'hardware designed like software', which means that the design process resembles software development but the end-product is considered a hardware application because the execution of the functions is entirely different from a microprocessor. This duality can give both the flexibility of software and the reliability of hardware. The FPGA design and verification and validation (V and V) methods for NPP safety systems have not yet matured because the technology is rather new in the field. Software development methods and stanfards can be used to some extent but the hardware aspects bring new challenges that cannot be tacled using purely software methods. International efforts are being made to development formal and consistent design and V and V methodology regulations for FPGA devices. A preventive safety function called Stepwise Shutdown System (SWS) was implemented on an Actel M1 IGLOO field-programmable gate array (FPGA) device. SWS is used to drive a process into a normal state if the process measurements deviate from the desired operating values. This can happen in case of process disturbances. The SWS implementation processfrom the reguirements to the functional device is elaborated. The design is tested via simulation and hardware testing. The case study is to be further expanded as a part of a master's thesis. (orig.)

  14. France: Reflections on the assessment of passive shutdown systems

    International Nuclear Information System (INIS)

    Baudrand, O.

    2015-01-01

    Passive shutdown systems (PSS) have been envisaged in the past project EFR developed in the 90’s. In practice, passive devices would have not replaced active shutdown systems. The PSS were proposed as a supplementary provision against core meltdown accident. The objective was to enhance the reliability of the emergency shutdown function by adding a completely independent and diversified “third shutdown system” (two active shutdown systems were envisaged in the basic design). In this frame, their efficiency was required essentially in case of postulated failure of the two active shutdown systems. It is to be noted that this approach is consistent with the required independence of the defense-in-depth levels. The IRSN considers that the shutdown system (I&C plus absorber rods and dedicated subassemblies) is of particular importance due to core physics typical of LMFRs. In relation to this, specific technical capabilities should be proven: - fast actuation and fall-down to cope with fast reactivity transients, - effectiveness under earthquake loading (insertion capability in case of core deformation), - actuation of the system in case of local subassembly fault (requires enhancement of detection for large cores), - effectiveness in case of partial core degradation In addition the shutdown system is needed to compensate for the positive coolant void effect (local or global void effect). Formally, the deterministic safety assessment of PSS should not be different from the one applied to active systems. But several questions arose when applying the standard assessment methods: - When a safety function is performed by active and passive systems, should the single failure criterion be applied to passive systems? - What kind of uncertainties should be explored in the performance analysis? - Are the qualification procedures different from those applicable to active systems? - How to ensure the sustainability of the performance of the PSS? Regarding the last point

  15. 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)

  16. Reactor protection and shut-down system

    International Nuclear Information System (INIS)

    Klar

    1980-01-01

    The reactor protection system being a part of the reactor safety system. The requirements on the reactor protection system are: high safety with regard to signal processing, high availability, self-reporting of faults etc. The functional sections of the reactor protection system are the analog section, the logic section and the generating of output signals. Description of the operation characteristics and of the extension of function. (orig.)

  17. Design Improvement Study for Passive Shutdown System of the PGSFR

    International Nuclear Information System (INIS)

    Lee, Jae-Han; Koo, Gyeong-Ho

    2014-01-01

    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) 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 design upgrade parametric study of a passive shutdown system, which consists of a thermal expansion device, an electromagnet, a secondary control rod assembly head, etc. The conceptual design values of each component are also suggested. Parametric calculations are performed to meet the performance requirements of the thermal expansion device and electromagnets. The maximum thermal expansion difference length of 3.6 mm is less than the target value of 5 mm, and the calculated electromagnet forces on the CRA are smaller than the target value of 800 N. An additional design improvement to increase the thermal expansion difference length of a thermal expansion device are necessary to meet the target value, and the electromagnetic force should be increased by an adjustment of the electromagnet design values such as supplied current, material permeability, etc. The design feasibility of the thermal expansion device as a passive concept will be verified based on these results

  18. Reliability modeling of Clinch River breeder reactor electrical shutdown systems

    International Nuclear Information System (INIS)

    Schatz, R.A.; Duetsch, K.L.

    1974-01-01

    The initial simulation of the probabilistic properties of the Clinch River Breeder Reactor Plant (CRBRP) electrical shutdown systems is described. A model of the reliability (and availability) of the systems is presented utilizing Success State and continuous-time, discrete state Markov modeling techniques as significant elements of an overall reliability assessment process capable of demonstrating the achievement of program goals. This model is examined for its sensitivity to safe/unsafe failure rates, sybsystem redundant configurations, test and repair intervals, monitoring by reactor operators; and the control exercised over system reliability by design modifications and the selection of system operating characteristics. (U.S.)

  19. 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)

  20. Modelling of liquid injection shutdown system (LISS) in ACR-1000

    International Nuclear Information System (INIS)

    Boubcher, M.; Colton, A.; Donnelly, J.V.

    2008-01-01

    Modelling of the Liquid Injection Shutdown System (LISS) in the ACR-1000 reactor core must account for the major phenomena that occur following its activation, namely the moderator hydraulics and core neutronics. The former requires modelling of the poison volumes, their time of entry into the reactor, and their propagation into the moderator after emission from the nozzle. The latter requires the reactivity worth of varying volumes and geometries of poisoned moderator fluid in order to simulate the reactivity effect of the injected poison. The time-dependent poison map is generated from hydraulic calculations, and then the neutronics data for standard geometries and concentrations is constructed using DRAGON. (author)

  1. Failure and Reliability Analysis for the Master Pump Shutdown System

    Energy Technology Data Exchange (ETDEWEB)

    BEVINS, R.R.

    2000-09-05

    The Master Pump Shutdown System (MPSS) will be installed in the 200 Areas of the Hanford Site to monitor and control the transfer of liquid waste between tank farms and between the 200 West and 200 East areas through the Cross-Site Transfer Line. The Safety Function provided by the MPSS is to shutdown any waste transfer process within or between tank farms if a waste leak should occur along the selected transfer route. The MPSS, which provides this Safety Class Function, is composed of Programmable Logic Controllers (PLCs), interconnecting wires, relays, Human to Machine Interfaces (HMI), and software. These components are defined as providing a Safety Class Function and will be designated in this report as MPSS/PLC. Input signals to the MPSS/PLC are provided by leak detection systems from each of the tank farm leak detector locations along the waste transfer route. The combination of the MPSS/PLC, leak detection system, and transfer pump controller system will be referred to as MPSS/SYS. The components addressed in this analysis are associated with the MPSS/SYS. The purpose of this failure and reliability analysis is to address the following design issues of the Project Development Specification (PDS) for the MPSS/SYS (HNF 2000a): (1) Single Component Failure Criterion, (2) System Status Upon Loss of Electrical Power, (3) Physical Separation of Safety Class cables, (4) Physical Isolation of Safety Class Wiring from General Service Wiring, and (5) Meeting the MPSS/PLC Option 1b (RPP 1999) Reliability estimate. The failure and reliability analysis examined the system on a component level basis and identified any hardware or software elements that could fail and/or prevent the system from performing its intended safety function.

  2. Bipolar square-wave current source for transient electromagnetic systems based on constant shutdown time.

    Science.gov (United States)

    Wang, Shilong; Yin, Changchun; Lin, Jun; Yang, Yu; Hu, Xueyan

    2016-03-01

    Cooperative work of multiple magnetic transmitting sources is a new trend in the development of transient electromagnetic system. The key is the bipolar current waves shutdown, concurrently in the inductive load. In the past, it was difficult to use the constant clamping voltage technique to realize the synchronized shutdown of currents with different peak values. Based on clamping voltage technique, we introduce a new controlling method with constant shutdown time. We use the rising time to control shutdown time and use low voltage power source to control peak current. From the viewpoint of the circuit energy loss, by taking the high-voltage capacitor bypass resistance and the capacitor of the passive snubber circuit into account, we establish the relationship between the rising time and the shutdown time. Since the switch is not ideal, we propose a new method to test the shutdown time by the low voltage, the high voltage and the peak current. Experimental results show that adjustment of the current rising time can precisely control the value of the clamp voltage. When the rising time is fixed, the shutdown time is unchanged. The error for shutdown time deduced from the energy consumption is less than 6%. The new controlling method on current shutdown proposed in this paper can be used in the cooperative work of borehole and ground transmitting system.

  3. Safety consideration and current trend in design of shutdown system of NPP

    International Nuclear Information System (INIS)

    Chandra, K.K.

    2011-01-01

    While reaping the benefit of nuclear energy issues related to nuclear safety shall be adequately addressed. Reactor Shutdown System plays a major role in ensuring safety in NPP by terminating any postulated reactivity excursion in the reactor core which is beyond the capability of regulating system to control and maintaining the reactor core to sub critical state with adequate margin. Shutdown system ensures this under all operating conditions with high degree of certainty. To achieve this objective design of shutdown system includes appropriate safety features whose adequacy is established through analysis, design verification and testing. Design shall be passively safe. Self actuating passive Shutdown systems are becoming popular because of their reliability. Objective of the paper is to describe the safety consideration and current trend in design of Shutdown System. (author)

  4. A pragmatic approach towards designing a second shutdown system for Tehran research reactor

    Directory of Open Access Journals (Sweden)

    Boustani Ehsan

    2016-01-01

    Full Text Available One second shutdown system is proposed for the Tehran Research Reactor to achieve the goal of higher safety in compliance with current operational requirements and regulations and improve the overall reliability of the reactor shutdown system. The proposed second shutdown system is a diverse, independent shutdown system compared to the existing rod based one that intends to achieve and maintain sub-criticality condition with an enough shutdown margin in many of abnormal situations. It is designed as much as practical based on neutron absorber solution injection into the existing core while the changes and interferences with the existing core structure are kept to a minimum. Core neutronic calculations were performed using MCNPX 2.6.0 and MTR_PC package for the current operational core equipped with the second shutdown system, and one experiment was conducted in the Tehran Research Reactor to test the neutronic calculations. A good agreement was seen between theoretical results and experimental ones. In addition, capability of the second shutdown system in the case of occurrence of design basis accident in the Tehran Research Reactor is demonstrated using PARET program.

  5. 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

  6. The Intelligent Safety System: could it introduce complex computing into CANDU shutdown systems

    International Nuclear Information System (INIS)

    Hall, J.A.; Hinds, H.W.; Pensom, C.F.; Barker, C.J.; Jobse, A.H.

    1984-07-01

    The Intelligent Safety System is a computerized shutdown system being developed at the Chalk River Nuclear Laboratories (CRNL) for future CANDU nuclear reactors. It differs from current CANDU shutdown systems in both the algorithm used and the size and complexity of computers required to implement the concept. This paper provides an overview of the project, with emphasis on the computing aspects. Early in the project several needs leading to an introduction of computing complexity were identified, and a computing system that met these needs was conceived. The current work at CRNL centers on building a laboratory demonstration of the Intelligent Safety System, and evaluating the reliability and testability of the concept. Some fundamental problems must still be addressed for the Intelligent Safety System to be acceptable to a CANDU owner and to the regulatory authorities. These are also discussed along with a description of how the Intelligent Safety System might solve these problems

  7. Experimental and analytical studies of a passive shutdown heat removal system for advanced LMRs

    International Nuclear Information System (INIS)

    Heineman, J.; Kraimer, M.; Lottes, P.; Pedersen, D.; Stewart, R.; Tessier, J.

    1988-01-01

    A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) is being used to investigate the heat transfer performance of the GE/PRISM and the RI/SAFR passive designs. This paper presents a description of the NSTF, the pretest analysis of the Radiant Reactor Vessel Auxiliary Cooling System (RVACS) in support of the GE/PRISM IFR concept, and experiment results for the RVACS simulation. Preliminary results show excellent agreement with predicted system performance

  8. Experimental and analytical studies of a passive shutdown heat removal system for advanced LMRs

    Energy Technology Data Exchange (ETDEWEB)

    Heineman, J.; Kraimer, M.; Lottes, P.; Pedersen, D.; Stewart, R.; Tessier, J.

    1988-01-01

    A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) is being used to investigate the heat transfer performance of the GE/PRISM and the RI/SAFR passive designs. This paper presents a description of the NSTF, the pretest analysis of the Radiant Reactor Vessel Auxiliary Cooling System (RVACS) in support of the GE/PRISM IFR concept, and experiment results for the RVACS simulation. Preliminary results show excellent agreement with predicted system performance.

  9. Development of a self-actuated shutdown system for a liquid-metal breeder reactor

    International Nuclear Information System (INIS)

    Cooper, M.H.; Tupper, R.B.; Bernard, A.M.

    1984-01-01

    A comprehensive development program for a Self-Actuated Shutdown System for a Liquid-Metal Fast Breeder Reactor has been completed. The development program included component tests of a temperature sensitive electromagnet, prototype test including the absorber in a sodium loop, accelerated life tests of the high temperature electric coils, and an irradiation test of a miniaturized coil and magnetic circuit materials. The results of these tests have demonstrated that the self-actuated shutdown system is sufficiently developed for application in the next generation Liquid-Metal Fast Breeder Reactor. (author)

  10. 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

  11. Access and Alarm Safety Systems - Activities for the 2012/2013 Long Shutdown

    CERN Document Server

    Grau, S; Ladzinski, T; Ninin, P; Nunes, R

    2011-01-01

    This paper presents the 2012/2013 long shutdown activities for the access, emergency evacuation, gas and fire detection systems. First, an overview of the required minimal annual maintenance and tests is presented; including the first feedback from the 9 weeks of the Technical Stop. Second, planned upgrades, new installations and consolidation activities, such as the R2E relocations and systems improvements, are discussed. For all these activities, the required resources are estimated, the constraints on other groups are listed, the associated risks analyzed and time estimation provided. The evaluation of the required resources takes into consideration the activities in the injector chain during the long shutdown.

  12. Technical Meeting on Passive Shutdown Systems for Liquid Metal-Cooled Fast Reactors. Working Material

    International Nuclear Information System (INIS)

    2015-01-01

    A major focus of the design of modern fast reactor systems is on inherent and passive safety. Specific systems to improve reactor safety performance during accidental transients have been developed in nearly all fast reactor programs, and a large number of proposed systems have reached various stages of maturity. This Technical Meeting on Passive Shutdown Systems for Fast Reactors, which was recommended by the Technical Working Group on Fast Reactors (TWG-FR), addressed Member States’ expressed need for information exchange on projects and programs in the field, as well as for the identification of priorities based on the analysis of technology gaps to be covered through R&D activities. This meeting was limited to shutdown systems only, and did not include other passive features such as natural circulation decay heat removal systems etc.; however the meeting catered to passive shutdown safety devices applicable to all types of fast neutron systems. It was agreed to initiate a new study and produce a Nuclear Energy Series (NES) Technical Report to collect information about the existing operational systems as well as innovative concepts under development. This will be a useful source for member states interested in gaining technical expertise to develop passive shutdown systems as well as to highlight the importance and development in this area

  13. 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

  14. 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

  15. 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)

  16. Preliminary aseismic analysis on bolts of driving mechanism in absorption sphere shutdown system

    International Nuclear Information System (INIS)

    Chen Feng; Li Tianjin; Zhang Zhengming; Huang Zhiyong; Bo Hanliang

    2012-01-01

    The absorption sphere shutdown system performs an important role in reactivity regulating and control. Driving mechanism is a set of key mechanical moving parts which is used to control falling of absorption spheres in absorption sphere shutdown system. It is about 5 m for driving mechanism with the slim structure, which is connected with the upper supported plate of metal reactor internals through storage vessel with bolts. Both the storage vessel and driving mechanism are equipment of seismic classification I. It is significant to calculate and check the bolts strength of driving mechanism. In this paper, complicate structure of driving mechanism was simplified to three variable cross sections and statically indeterminate problem was solved. The bolts at the bottom and on the top of the storage vessel were calculated and checked. The preliminary results indicate that the bolts strength is reliable and safe, and the supporting force at the most weak point of driving mechanism is as well obtained. (authors)

  17. Advances in the physics modelling of CANDU liquid injection shutdown systems

    International Nuclear Information System (INIS)

    Smith, H.J.; Robinson, R.; Guertin, C.

    1993-01-01

    The physics modelling of liquid poison injection shutdown systems in CANDU reactors accounts for the major phenomena taking place by combining the effects of both moderator hydraulics and neutronics. This paper describes the advances in the physics modelling of liquid poison injection shutdown systems (LISS), discusses some of the effects of the more realistic modelling, and briefly describes the automation methodology. Modifications to the LISS methodology have improved the realism of the physics modelling, showing that the previous methodology significantly overestimated energy deposition during the simulation of a loss of coolant transient in Bruce A, by overestimating the reactivity transient. Furthermore, the automation of the modelling process has reduced the time needed to carry put LISS evaluations to the same level as required for shutoff-rod evaluations, while at the same time minimizing the amount of input, and providing a method for tracing all files used, thus adding a level of quality assurance to the calculation. 5 refs., 11 figs

  18. 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

  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. Evolving the JET virtual reality system for delivering the JET EP2 shutdown remote handling tasks

    International Nuclear Information System (INIS)

    Williams, Adrian; Sanders, Stephen; Weder, Gerard; Bastow, Roger; Allan, Peter; Hazel, Stuart

    2011-01-01

    The quality, functionality and performance of the virtual reality (VR) system used at JET for preparation and implementation of remote handling (RH) operations has been progressively enhanced since its first use in the original JET remote handling shutdown in 1998. As preparation began for the JET EP2 (Enhanced Performance 2) shutdown it was recognised that the VR system being used was unable to cope with the increased functionality and the large number of 3D models needed to fully represent the JET in-vessel components and tooling planned for EP2. A bespoke VR software application was developed in collaboration with the OEM, which allowed enhancements to be made to the VR system to meet the requirements of JET remote handling in preparation for EP2. Performance improvements required to meet the challenges of EP2 could not be obtained from the development of the new VR software alone. New methodologies were also required to prepare source, CATIA models for use in the VR using a collection of 3D software packages. In collaboration with the JET drawing office, techniques were developed within CATIA using polygon reduction tools to reduce model size, while retaining surface detail at required user limits. This paper will discuss how these developments have played an essential part in facilitating EP2 remote handling task development and examine their impact during the EP2 shutdown.

  1. Reserves for shutdown/dismantling and disposal in nuclear technology. Theses and recommendations on reform options; Rueckstellungen fuer Stilllegung/Rueckbau und Entsorgung im Atombereich. Thesen und Empfehlungen zu Reformoptionen

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Bettina [Forum Oekologisch-Soziale Marktwirtschaft e.V. (FOeS), Berlin (Germany). Green Budget Germany (GBG)

    2012-04-11

    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.

  2. Control assembly for controlling a fuel cell system during shutdown and restart

    Science.gov (United States)

    Venkataraman, Ramki; Berntsen, George; Carlson, Glenn L.; Farooque, Mohammad; Beachy, Dan; Peterhans, Stefan; Bischoff, Manfred

    2010-06-15

    A fuel cell system and method in which the fuel cell system receives and an input oxidant gas and an input fuel gas, and in which a fuel processing assembly is provided and is adapted to at least humidify the input fuel gas which is to be supplied to the anode of the fuel cell of the system whose cathode receives the oxidant input gas via an anode oxidizing assembly which is adapted to couple the output of the anode of the fuel cell to the inlet of the cathode of the fuel cell during normal operation, shutdown and restart of the fuel cell system, and in which a control assembly is further provided and is adapted to respond to shutdown of the fuel cell system during which input fuel gas and input oxidant gas cease to be received by the fuel cell system, the control assembly being further adapted to, when the fuel cell system is shut down: control the fuel cell system so as to enable a purging gas to be able to flow through the fuel processing assembly to remove humidified fuel gas from the processing assembly and to enable a purging gas to be able to flow through the anode of the fuel cell.

  3. Requirements Analysis Study for Master Pump Shutdown System Project Development Specification [SEC 1 and 2

    International Nuclear Information System (INIS)

    BEVINS, R.R.

    2000-01-01

    This document has been updated during the definitive design portion of the first phase of the W-314 Project to capture additional software requirements and is planned to be updated during the second phase of the W-314 Project to cover the second phase of the Project's scope. The objective is to provide requirement traceability by recording the analysis/basis for the functional descriptions of the master pump shutdown system. This document identifies the sources of the requirements and/or how these were derived. Each requirement is validated either by quoting the source or an analysis process involving the required functionality, performance characteristics, operations input or engineering judgment

  4. Requirements Analysis Study for Master Pump Shutdown System Project Development Specification [SEC 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    BEVINS, R.R.

    2000-03-24

    This document has been updated during the definitive design portion of the first phase of the W-314 Project to capture additional software requirements and is planned to be updated during the second phase of the W-314 Project to cover the second phase of the Project's scope. The objective is to provide requirement traceability by recording the analysis/basis for the functional descriptions of the master pump shutdown system. This document identifies the sources of the requirements and/or how these were derived. Each requirement is validated either by quoting the source or an analysis process involving the required functionality, performance characteristics, operations input or engineering judgment.

  5. 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

  6. Skyline Reservation System

    Data.gov (United States)

    US Agency for International Development — Flight reservation application used for in-country flights by USAID and DoS staff in Afghanistan. The application is managed and maintained by the vendor and USAID...

  7. Brief account of the design philosophy for third Qinshan NPP shutdown safety system based on practical application

    International Nuclear Information System (INIS)

    Xiong Weihua

    2005-01-01

    Qinshan CANDU power plant is uses the Canadian proven CANDU6 nuclear power technology. It has two characteristic: 1. heavy water-as moderator and coolant; 2. natural uranium as the fuel and change fuel during normal operating. CANDU6 include four special safety system: the No.1 shutdown system (SDS No.1), the No.2 shutdown system (SDS No.2), the containment system, the emergency core cooling system (ECCS). QinShan CANDU power plant is the first commercial PHWR nuclear power plant in China. And some aspect is not similar to everybody. The intention of the article is to introduce the basic design and functions. (authors)

  8. Development of Risk Assessment Technology for Low Power, Shutdown and Digital I and C System

    International Nuclear Information System (INIS)

    Jang, Seung Cheol; Kang, Hyun Gook; Lim, Ho Gon; Park, Jin Hee; Kang, Dae Il; Eom, Heung Sub; Kim, Man Cheol; Lee, Ho Joong; Kim, Jae Whan; Ha, Jae Joo

    2007-06-01

    There are two technical areas to deal with in the project: the low power and shutdown probabilistic safety assessment (PSA), and the digital I and C PSA. The scope and contents of each area could be summarized as follows: The LPSD PSA Area Ο Quality improvement of the KSNP LPSD PSA model in the following four technical areas; human reliability analysis (HR), system analysis (SY), data analysis (DA) and accident sequence quantification (QU) Ο Development of the LPSD configuration risk management(CRM) model - Study on the methodology for developing a CRM model, so-called ASLOC (Autonomous Shutdown LOgic Creation) - Development of the LPSD CRM model for the units of Ulchin 3 and 4 The Digital I and C PSA Area Ο Development of impact model of ESF-CCS on plant risks - Unavailability analysis of ESF-CCS for APR-1400 - Digital plant risk models for evaluating core damage frequency (CDF) Ο Study on the methodologies for treating digital-specific problems in the digital I and C PSA - Study on the methodology for evaluating safety-critical SW reliability by BBN techniques, including a feasibility study of reliability growth model - Study on the methodology for the safety-critical network system by Markov chain

  9. Evolution of the ATLAS Distributed Computing system during the LHC Long shutdown

    CERN Document Server

    Campana, S; The ATLAS collaboration

    2014-01-01

    The ATLAS Distributed Computing project (ADC) was established in 2007 to develop and operate a framework, following the ATLAS computing model, to enable data storage, processing and bookkeeping on top of the WLCG distributed infrastructure. ADC development has always been driven by operations and this contributed to its success. The system has fulfilled the demanding requirements of ATLAS, daily consolidating worldwide up to 1PB of data and running more than 1.5 million payloads distributed globally, supporting almost one thousand concurrent distributed analysis users. Comprehensive automation and monitoring minimized the operational manpower required. The flexibility of the system to adjust to operational needs has been important to the success of the ATLAS physics program. The LHC shutdown in 2013-2015 affords an opportunity to improve the system in light of operational experience and scale it to cope with the demanding requirements of 2015 and beyond, most notably a much higher trigger rate and event pileu...

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  11. Requirements Analysis Study for Master Pump Shutdown System Project Development Specification

    International Nuclear Information System (INIS)

    BEVINS, R.R.

    2000-01-01

    This study is a requirements document that presents analysis for the functional description for the master pump shutdown system. This document identifies the sources of the requirements and/or how these were derived. Each requirement is validated either by quoting the source or an analysis process involving the required functionality, performance characteristics, operations input or engineering judgment. The requirements in this study apply to the first phase of the W314 Project. This document has been updated during the definitive design portion of the first phase of the W314 Project to capture additional software requirements and is planned to be updated during the second phase of the W314 Project to cover the second phase of the project's scope

  12. Requirements Analysis Study for Master Pump Shutdown System Project Development Specification [SEC 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    BEVINS, R.R.

    2000-09-20

    This study is a requirements document that presents analysis for the functional description for the master pump shutdown system. This document identifies the sources of the requirements and/or how these were derived. Each requirement is validated either by quoting the source or an analysis process involving the required functionality, performance characteristics, operations input or engineering judgment. The requirements in this study apply to the first phase of the W314 Project. This document has been updated during the definitive design portion of the first phase of the W314 Project to capture additional software requirements and is planned to be updated during the second phase of the W314 Project to cover the second phase of the project's scope.

  13. Fractional Reserve in Banking System

    OpenAIRE

    Valkonen, Maria

    2016-01-01

    This thesis is aimed to provide understanding of the role of the fractional reserve in the mod-ern banking system worldwide and particularly in Finland. The fractional reserve banking is used worldwide, but the benefits of this system are very disputable. On the one hand, experts say that the fractional reserve is a necessary instrument for the normal business and profit making. On the other hand, sceptics openly criticize the fractional reserve system and blame it for fiat money (money n...

  14. Optimum design for the primary cooling system in BWRs to control shutdown radiation dose rate

    International Nuclear Information System (INIS)

    Miki, Minoru; Saito, Tatsuya; Uchida, Shunsuke; Izumiya, Masakiyo.

    1982-01-01

    The reduction of radiation dose rate at the time of shutdown is an important task for smoothly performing the regular inspection and maintenance works in nuclear power plants as the number of those plants in operation has increased. Hitachi Ltd. has investigated the industrially applicable measures to reduce dose rate to suppress the exposure dose per year in 1100 MWe class BWR nuclear power plants below 200 Man-Rem. The exposure dose in normal checking works during a regular inspection is regarded to be macroscopically dependent on the dose rate of piping in recirculation system. Thus, it was found that the above target can be achieved by suppressing the dose rate on piping surface to 30 mR/h. For further reduction if iron crud and 60 Co ions contributing to the increase of dose rate, in addition to the oxygen injection into the feed water system and the duplicated condensate purification system, the use of corrosion-resistant steel and low cobalt material has been attempted. However, high temperature water to be filtrated can not be passed through the purification system because it employs ion exchange resin. Therefore, the optimum capacity is selected for the purification system in view of the reduction of dose rate and plant thermal efficiency. Hitachi Ltd. recommends the application of this system, considering the evaluation of contribution by the code predicting dose rate increase and estimating economy. The above measures will achieve the exposure dose target of 200 Man-Rem/year. (Wakatsuki, Y.)

  15. Development of Risk Assessment Technology for Low Power, Shutdown and Digital I and C Systems

    International Nuclear Information System (INIS)

    Jang, Seung Cheol; Kang, Hyung Gook; Lim, Ho Gon; Park, Jin Hee; Eom, Heung Sub; Kim, Tae Woon; Ha, Jae Joo

    2005-04-01

    There are two technical areas to deal with in the project; the low power and shutdown probabilistic safety assessment (PSA), and the digital I and C PSA. The scope and contents of each area could be summarized as follows: Quality assessment of a LPSD PSA model for a Korean Standard Nuclear Power Plant (KSNP), Quality improvement of the KSNP LPSD PSA model in the following four technical areas; plant operating status (POS), initiating event analysis, determination of success criteria, accident sequence analysis, Development of the LPSD risk management technologies, Unavailability analysis of Digital safety systems such as Digital Plant Protection System (DPPS) and Digital Engineered Safety Feature Actuation System (DESFAS), Impact analysis of the digital safety systems on plant risks throughout of the digital plant risk models for evaluating core damage frequency (CDF) and large early release frequency (LERF), Study on the methodologies for treating digital-specific problems in the digital I and C PSA such as reliability of safety-critical software, common cause failure (CCF) of digital components, fault coverage, etc

  16. An analysis of multiple particle settling for LMR backup shutdown systems

    International Nuclear Information System (INIS)

    Brock, R.W.

    1992-05-01

    Backup shutdown systems proposed for future LMRs may employ discreet absorber particles to provide the negative reactivity insertion. When actuated, these systems release a dense packing of particles from an out-of-core region to settle into an in-core region. The multiple particle settling behavior is analyzed by the method of continuity waves. This method provides predictions of the dynamic response of the system including the average particle velocity and volume fraction of particles vs. time. Although hindered settling problems have been previously analyzed using continuity wave theory, this application represents an extension of the theory to conditions of unrestrained settling. Typical cases are analyzed and numerical results are calculated based on a semi-empirical drift-flux model. For 1/4-inch diameter boron-carbide particles in hot liquid sodium, the unrestrained settling problem assumes a steady-state solution when the average volume fraction of particles is 0.295 and the average particle velocity is 26.0 cm/s

  17. 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.)

  18. Probabilistic cost-benefit seismic design criterion for a dedicated shutdown heat removal system

    International Nuclear Information System (INIS)

    Lee, Y.T.; Okrent, D.

    1985-01-01

    A probabilistic methodology is developed for assessing the risk reduction potential and cost-benefit tradeoff of a Dedicated Shutdown Heat Removal System (DSHRS) for a PWR as a function of its seismic design capability. The option of coping with a very small LOCA is included. The annual seismic risk of a plant and a similar hypothetical plant having a proposed DSHRS with various seismic strengths are computed. The difference in the annual seismic risks is the annual seismic risk reduction benefit for having the system. The present value of the future risk reduction benefit is then compared to the cost of building a DSHRS and the incremental seismic cost associated with building the system to withstand a stronger earthquake. A reactor like Zion was used for application of the method due to the availability of data. Studies were performed to investigate the sensitivity of the results to the assumed seismic hazard, probability of occurrence of seismic-induced accident initiating events, equipment seismic fragility, accident costs, and discount rate. The incremental seismic risk reduction benefit computed in these studies ranges from Dollar 207 million for a DSHRS with a median seismic capacity of 1.70g (i.e. 10 x SSE) in a new plant built at the site. The total cost of a DSHRS is crudely estimated to be Dollar 25 million or more, if it were built to withstand the current SSE of the plant (for which the system probably would have a median seismic capacicty of 0.85g or more due to various design and construction conservatisms). The cost associated with the seismic design aspect of such a system is estimated to be approximately Dollar 2.5 million and it may be doubled if the seismic design capability of the system is tripled. The cost/benefit results and their inherent large uncertainties are not definitive but indicate that probabilistic seismic design of a DSHRS should be examined in further detail. (orig.)

  19. Pilot Operation of Ex-core Neutron Sensors of Divers Shutdown System (DSS) Unit 2 Ignalina NPP

    International Nuclear Information System (INIS)

    Jakshtonis, Z.; Krivoshei, G.

    2006-01-01

    The Ignalina Safety Assessment, which was completed in December 1996, recommended the installation of a diverse shutdown system on the 2nd unit at Ignalina. During the PPR-2004 in the DSS project are created two independent shutdown systems by separating the absorber rods into two independent groups as follows: 1. One system (designated AZ) consists of the existing 24 BAZ rods and 49 AZ/BSM rods that together are used for reliable reactor shutdown (including Control and Protection System (CPS) circuit voiding accident). This system performs the emergency protection function. 2. The other system (designated BSM) comprises the remaining absorber rods and the 49 AZ/BSM rods. Thus 49 AZ/BSM rods are actuated from AZ initiating equipment as well as from BSM initiating equipment. The BSM system performs the normal reactor shutdown function and is able to ensure long-term maintenance of the reactor in the sub-critical state. Along with implementation of DSS was modernized existing Emergency Process Protection System, which was divided into two independent Sets of initiating equipment. The DSS is independent and diverse initiating equipment from the existing 1st Set equipment; with each set having its own independent in-core and ex-core sensors for measurement of neutron flux and process parameters. The 2nd Set of initiating equipment for measuring ex-core neutron flux, was modernized with new design of 4 Ex-Core detectors each have a single low level neutron flux detector and two high range neutron detectors. They are comprising: 1. A fission chamber which operates in pulse mode to cover the low flux levels. 2. A compensated ionisation chamber in current mode to operate at high flux level. This detector is doubled to give a measurement of the axial deviation. Two detectors are enough to produce the axial power deviation. The results of testing and analysis of pilot operation of ex-core neutron sensors of DSS will be shown on the Report. (author)

  20. Evolution of the ATLAS distributed computing system during the LHC long shutdown

    Science.gov (United States)

    Campana, S.; Atlas Collaboration

    2014-06-01

    The ATLAS Distributed Computing project (ADC) was established in 2007 to develop and operate a framework, following the ATLAS computing model, to enable data storage, processing and bookkeeping on top of the Worldwide LHC Computing Grid (WLCG) distributed infrastructure. ADC development has always been driven by operations and this contributed to its success. The system has fulfilled the demanding requirements of ATLAS, daily consolidating worldwide up to 1 PB of data and running more than 1.5 million payloads distributed globally, supporting almost one thousand concurrent distributed analysis users. Comprehensive automation and monitoring minimized the operational manpower required. The flexibility of the system to adjust to operational needs has been important to the success of the ATLAS physics program. The LHC shutdown in 2013-2015 affords an opportunity to improve the system in light of operational experience and scale it to cope with the demanding requirements of 2015 and beyond, most notably a much higher trigger rate and event pileup. We will describe the evolution of the ADC software foreseen during this period. This includes consolidating the existing Production and Distributed Analysis framework (PanDA) and ATLAS Grid Information System (AGIS), together with the development and commissioning of next generation systems for distributed data management (DDM/Rucio) and production (Prodsys-2). We will explain how new technologies such as Cloud Computing and NoSQL databases, which ATLAS investigated as R&D projects in past years, will be integrated in production. Finally, we will describe more fundamental developments such as breaking job-to-data locality by exploiting storage federations and caches, and event level (rather than file or dataset level) workload engines.

  1. Evolution of the ATLAS distributed computing system during the LHC long shutdown

    International Nuclear Information System (INIS)

    Campana, S

    2014-01-01

    The ATLAS Distributed Computing project (ADC) was established in 2007 to develop and operate a framework, following the ATLAS computing model, to enable data storage, processing and bookkeeping on top of the Worldwide LHC Computing Grid (WLCG) distributed infrastructure. ADC development has always been driven by operations and this contributed to its success. The system has fulfilled the demanding requirements of ATLAS, daily consolidating worldwide up to 1 PB of data and running more than 1.5 million payloads distributed globally, supporting almost one thousand concurrent distributed analysis users. Comprehensive automation and monitoring minimized the operational manpower required. The flexibility of the system to adjust to operational needs has been important to the success of the ATLAS physics program. The LHC shutdown in 2013-2015 affords an opportunity to improve the system in light of operational experience and scale it to cope with the demanding requirements of 2015 and beyond, most notably a much higher trigger rate and event pileup. We will describe the evolution of the ADC software foreseen during this period. This includes consolidating the existing Production and Distributed Analysis framework (PanDA) and ATLAS Grid Information System (AGIS), together with the development and commissioning of next generation systems for distributed data management (DDM/Rucio) and production (Prodsys-2). We will explain how new technologies such as Cloud Computing and NoSQL databases, which ATLAS investigated as R and D projects in past years, will be integrated in production. Finally, we will describe more fundamental developments such as breaking job-to-data locality by exploiting storage federations and caches, and event level (rather than file or dataset level) workload engines.

  2. LHC Detector Vacuum System Consolidation for Long Shutdown 1 (LS1) in 2013-2014

    CERN Document Server

    Gallilee, M; Cruikshank, P; Gallagher, J; Garion, C; Jimenez, J M; Kersevan, R; Kos, H; Leduc, L; Lepeule, P; Provot, N; Rambeau, H; Veness, R

    2012-01-01

    The LHC has ventured into unchartered territory for Particle Physics accelerators. A dedicated consolidation program is required between 2013 and 2014 to ensure optimal physics performance. The experiments, ALICE, ATLAS, CMS, and LHCb, will utilise this shutdown, along with the gained experience of three years of physics running, to make optimisations to their detectors. New vacuum technologies have been developed for the experimental areas, to be integrated during this first phase shutdown. These technologies include bellows, vacuum chambers and ion pumps in aluminium, new beryllium vacuum chambers, and composite mechanical supports. An overview of this first phase consolidation program for the LHC experiments is presented.

  3. Behavior of ruthenium in the case of shutdown of the cooling system of HLLW storage tanks

    International Nuclear Information System (INIS)

    Philippe, M.; Mercier, J.P.; Gue, J.P.

    1990-01-01

    The consequences of the failure of the cooling system of fission product storage tanks over a variable period were investigated as part of the safety analysis of the La Hague spent fuel reprocessing plant. Due to the considerable heat release, induced by the fission products, a prolonged shutdown of the tank cooling system could cause the progressive evaporation of the solutions to dryness, and culminate in the formation of volatile species of ruthenium and their release in the tank venting circuit. To determine the fraction of ruthenium likely to be transferred from the storage tanks in volatile or aerosol form during the failure, evaporation tests were conducted by evaporating samples of actual nitric acid solutions of fission products, obtained on the laboratory scale after the reprocessing of several kilograms of MOX fuels irradiated to 30,000 MWday.t -1 . A distillation apparatus was designed to operate with small volume solution samples, reproducing the heating conditions existing in the reprocessing plant within a storage tank for fission products. The main conclusions drawn from these experiments are as follows: - ruthenium is only volatilized in the final phase of evaporation, just before desiccation, - for a final temperature limited to 160 0 C, the total fraction of volatilized ruthenium reaches 12%, in the presence of H 2 0, HN0 3 , N0 x and 0 2 , the volatilized ruthenium recombines mainly in the form of ruthenium nitrosyl nitrates, or decomposes into ruthenium oxide on the walls of the apparatus. Assuming a heating power density of 10 W/liter of concentrate, and a perfectly adiabatic storage system, the minimum time required to reach dryness can be estimated at 90 h, allowing substantial time to take action to restore a cooling source

  4. Behavior of ruthenium in the case of shutdown of the cooling system of HLLW storage tanks

    International Nuclear Information System (INIS)

    Philippe, M.; Mercier, J.P.; Gue, J.P.

    1991-01-01

    The consequences of the failure of the cooling system of fission product storage tanks over a variable period were investigated as part of the safety analysis of the La Hague spent fuel reprocessing plant. Due to the considerable heat release, induced by the fission products, a prolonged shutdown of the tank cooling system could cause the progressive evaporation of the solutions to dryness, and culminate in the formation of volatile species of ruthenium and their release in the tank venting circuit. To determine the fraction of ruthenium likely to be transferred from the storage tanks in volatile or aerosol form during the failure, evaporation tests were conducted by evaporating samples of actual nitric acid solutions of fission products, obtained on the laboratory scale after the reprocessing of several kilograms of MOX fuels irradiated to 30,000 MW day·t -1 . A distillation apparatus was designed to operate with small-volume solution samples, reproducing the heating conditions existing in the reprocessing plant within a storage tank for fission products. The main conclusions drawn from these experiments are as follows: ruthenium is only volatilized in the final phase of evaporation, just before desiccation; for a final temperature limited to 160 degree C, the total fraction of volatilized ruthenium reaches 12%; in the presence of H 2 O, HNO 3 , NO x and O 2 , the volatilized ruthenium recombines mainly in the form of ruthenium nitrosyl nitrates, or decomposes into ruthenium oxide (probably RuO 2 ) on the walls of the apparatus. Assuming a heating power density of 10 W/liter of concentrate, and a perfectly adiabatic storage system, the minimum time required to reach dryness can be estimated at 90 h, allowing substantial time to take action to restore a cooling source

  5. Maintenance of shutdown system in the reactor core to minimize the radioactive waste generation

    International Nuclear Information System (INIS)

    Ponzoni Filho, P.; Fernandes, V.B.

    1988-01-01

    This paper recommends a modification on the actual strategy of going from Cold-Shutdown to Critical, that will save about 6000 liter of boric acid and 30,000 liters of demineralized water for each reactor criticalization. This strategy will reduce the radioactive waste disposal volume to only about 5% of what would be generated following the actual strategy. (author) [pt

  6. Behaviour of ruthenium in the case of shutdown of the cooling system of HLLW storage tanks

    International Nuclear Information System (INIS)

    Philippe, M.; Gue, J.P.; Mercier, J.P.

    1990-12-01

    The consequences of the failure of the cooling system of fission product storage tanks over a variable period were investigated as part of the safety analysis of the La Hague spent fuel reprocessing plant. Due to the considerable heat release, induced by the fission products, a prolonged shutdown of the tank cooling system could cause the progressive evaporation of the solutions to dryness, and culminate in the formation of volatile species of ruthenium and their release in the tank venting circuit. To determine the fraction of ruthenium likely to be transferred from the storage tanks in volatile or aerosol form during the failure, evaporation tests were conducted by evaporating samples of actual nitric acid solutions of fission products, obtained on the laboratory scale after the reprocessing of several kilograms of MOX fuels irradiated to 30.000 MW day ·t -1 . A distillation apparatus was designed to operate with small-volume solution samples, reproducing the heating conditions existing in the reprocessing plant within a storage tank for fission products. The main conclusions drawn from these experiments are as follows: - ruthenium is only volatilized in the final phase of evaporation, just before desiccation, - for a final temperature limited to 160 deg. C, the total fraction of volatilized ruthenium reaches 12%, - in the presence of H 2 O, HNO 3 , NO x and O 2 , the volatilized ruthenium recombines mainly in the form of ruthenium nitrosyl nitrates, or decomposes into ruthenium oxide (probably RuO 2 ) on the walls of the apparatus. Assuming a heating power density of 10 W/liter of concentrate, and a perfectly adiabatic storage system, the minimum time required to reach dryness can be estimated at 90 h, allowing substantial time to take action to restore a cooling source. It is probable that, in an industrial storage tank, the heat losses from the tank and the offgas discharge ducts will cause recondensation and internal reflux, which will commensurately delay

  7. 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...

  8. 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)

  9. Complex of technologies and prototype systems for eco-friendly shutdown of the power-generating, process, capacitive, and transport equipment

    Science.gov (United States)

    Smorodin, A. I.; Red'kin, V. V.; Frolov, Y. D.; Korobkov, A. A.; Kemaev, O. V.; Kulik, M. V.; Shabalin, O. V.

    2015-07-01

    A set of technologies and prototype systems for eco-friendly shutdown of the power-generating, process, capacitive, and transport equipment is offered. The following technologies are regarded as core technologies for the complex: cryogenic technology nitrogen for displacement of hydrogen from the cooling circuit of turbine generators, cryo blasting of the power units by dioxide granules, preservation of the shutdown power units by dehydrated air, and dismantling and severing of equipment and structural materials of power units. Four prototype systems for eco-friendly shutdown of the power units may be built on the basis of selected technologies: Multimode nitrogen cryogenic system with four subsystems, cryo blasting system with CO2 granules for thermal-mechanical and electrical equipment of power units, and compressionless air-drainage systems for drying and storage of the shutdown power units and cryo-gas system for general severing of the steam-turbine power units. Results of the research and pilot and demonstration tests of the operational units of the considered technological systems allow applying the proposed technologies and systems in the prototype systems for shutdown of the power-generating, process, capacitive, and transport equipment.

  10. A Study on the Risk Reduction Effect by MLCS (Mid-loop Level Control System) of EUAPR using the Low-Power and Shutdown PSA Result

    International Nuclear Information System (INIS)

    Lee, Keunsung; Choi, Sunmi; Kim, Eden

    2016-01-01

    The EU-APR design has been developed in order to expand and diversify the global nuclear power market of APR1400. For the improvement of shutdown risk for the EUAPR, the mid-loop level control system (MLCS) is considered during mid-loop operation for the EU-APR, which is not incorporated into SKN 3 and 4 (APR1400 Type) in Korea. Commonly, the risk associated with the NPP can be identified through the PSA. Thus, this paper discusses the low power and shutdown (LPSD) risk reduction effect by MLCS using the Low-Power and Shutdown PSA Result. LPSD level 1 PSA models for EU-APR have been developed. The risk reduction effect by MLCS is discussed. Because the loss of shutdown cooling function during mid-loop is one of the most vulnerable events, the MLCS have a significant influence on CDF in LPSD PSA. The shutdown risk of domestic power plants would likely be reduced if the MLCS is adopted in all operating NPPs in Korea during the mid-loop operation. It is expected that this work will contribute to reduce shutdown risk of domestic power plants

  11. The application and design of distributed control system in reactor shutdown system of Qinshan phase III

    International Nuclear Information System (INIS)

    Su Guoquan; Liu Wangtian; Yu Yijun; Xiong Weihua

    2006-03-01

    The design, commissioning and running of the reactor trip parameter monitoring system used in Qinshan Phase III are introduced. The applying technology of Distributed Control System realized trip parameter monitoring and realized the function of trip parameters quick data acquisitioning, transferring, saving, alarm, query. The applying of trip parameters monitoring system improved the abilities of plant status monitoring and event analyzing, and increased the security and economy of nuclear power plant. (authors)

  12. Federal Reserve System Semiannual Regulatory Agenda

    Science.gov (United States)

    2010-12-20

    ... [The Regulatory Plan and Unified Agenda of Federal Regulatory and Deregulatory Actions] [Federal Reserve System Semiannual Regulatory Agenda ] Part XXI Federal Reserve System Semiannual Regulatory Agenda... Flexibility Agenda AGENCY: Board of Governors of the Federal Reserve System. ACTION: Semiannual regulatory...

  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. Reactor shutdown method

    International Nuclear Information System (INIS)

    Nishino, Yoshitaka; Sawa, Toshio; Matsumoto, Takayuki; Osumi, Katsumi; Usui, Naoshi.

    1991-01-01

    A device for injecting a hydrogen gas, a chelating agent or a reducing agent is disposed in a reactor water recycling system. Upon reactor shutdown, the hydrogen gas, the chelating agent or the reducing agent is injected to primary coolants. With such a procedure, radioactive ions formed by the dissolution of oxide layers at the surface of pipelines and equipments in a reactor water recycling system and a reactor water cleanup system are removed from the primary coolants by a reactor water cleanup device. Accordingly, since the dose rate at the surface of the pipelines can be reduced, the operator's radiation dose can be reduced upon periodical inspection for a power plant. Further, the inner pressure of the reactor is kept higher than the saturated steam pressure at the reactor water temperature to suppress boiling of the reactor water. This can suppress the peeling of cruds deposited to the surface of the fuel cladding tube. (I.N.)

  15. Technical Specification action statements requiring shutdown. A risk perspective with application to the RHR/SSW systems of a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Mankamo, T. [Avaplan Oy, Espoo (Finland); Kim, I.S.; Samanta, P.K. [Brookhaven National Lab., Upton, NY (United States)

    1993-11-01

    When safety systems fail during power operation, the limiting conditions for operation (LCOs) and associated action statements of technical specifications typically require that the plant be shut down within the limits of allowed outage time (AOT). However, when a system needed to remove decay heat, such as the residual heat removal (RHR) system, is inoperable or degraded, shutting down the plant may not necessarily be preferable, from a risk perspective, to continuing power operation over a usual repair time, giving priority to the repairs. The risk impact of the basic operational alternatives, i.e., continued operation or shutdown, was evaluated for failures in the RHR and standby service water (SSW) systems of a boiling-water reactor (BWR) nuclear power plant. A complete or partial failure of the SSW system fails or degrades not only the RHR system but other front-line safety systems supported by the SSW system. This report presents the methodology to evaluate the risk impact of LCOs and associated AOT; the results of risk evaluation from its application to the RHR and SSW systems of a BWR; the findings from the risk-sensitivity analyses to identify alternative operational policies; and the major insights and recommendations to improve the technical specifications action statements.

  16. Experience in ultrasonic gap measurement between calandria tubes and liquid injection shutdown systems nozzles in Bruce Nuclear Generating Station

    International Nuclear Information System (INIS)

    Abucay, R.C.; Mahil, K.S.; Goszczynski, J.J.

    1995-01-01

    The gaps between calandria tubes (CT) and Liquid Injection Shutdown System (LISS) nozzles at the Bruce Nuclear Generating Station ''A'' (Bruce A) are known to decrease with time due to radiation induced creep/sag of the calandria tubes. If this gap decreases to a point where the calandria tubes come into contact with the LISS nozzle, the calandria tubes could fail as a result of fretting damage. Proximity measurements were needed to verify the analytical models and ensure that CT/LISS nozzle contact does not occur earlier than predicted. The technique used was originally developed at Ontario Hydro Technologies (formerly Ontario Hydro Research Division) in the late seventies and put into practical use by Research and Productivity Council (RPC) of New Brunswick, who carried out similar measurements at Point Lepreau NGS in 1989 and 1991. The gap measurement was accomplished y inserting an inspection probe, containing four ultrasonic transducers (2 to measure gaps and 2 to check for probe tilt) and a Fredericks electrolytic potentiometer as a probe rotational sensor, inside LISS Nozzle number-sign 7. The ultrasonic measurements were fed to a system computer that was programmed to convert the readings into fully compensated gaps, taking into account moderator heavy water temperature and probe tilt. Since the measured gaps were found to be generally larger than predicted, the time to CT/LISS nozzle contact is now being re-evaluated and the planned LISS nozzle replacement will likely be deferred, resulting in considerable savings

  17. Reactor shutdown device

    International Nuclear Information System (INIS)

    Masuda, Hiroyuki.

    1983-01-01

    Purpose : To provide a reactor shutdown device suitable to the low temperature shutdown of a heavy water-moderated type nuclear reactor and capable of ensuring an adequate shutdown margin. Constitution : Xenon reactivity is calculated based on the detection signals for reactor neutrons, the temperature reactivity is calculated based on the temperature of the moderators and of the coolants and, further, poisons in the moderators are detected. Injection amount of the poisons is calculated based on the result of the calculation and the detection, and the calculated amount of poisons is injected into the moderators. (Kamimura, M.)

  18. Reservation system with graphical user interface

    KAUST Repository

    Mohamed, Mahmoud A. Abdelhamid

    2012-01-05

    Techniques for providing a reservation system are provided. The techniques include displaying a scalable visualization object, wherein the scalable visualization object comprises an expanded view element of the reservation system depicting information in connection with a selected interval of time and a compressed view element of the reservation system depicting information in connection with one or more additional intervals of time, maintaining a visual context between the expanded view and the compressed view within the visualization object, and enabling a user to switch between the expanded view and the compressed view to facilitate use of the reservation system.

  19. Shutdown of the River Water System at the Savannah River Site: Draft environmental impact statement

    International Nuclear Information System (INIS)

    1996-11-01

    This environmental impact statement (EIS) evaluates alternative approaches to and environmental impacts of shutting down the River Water System at the Savannah River Site (SRS). Five production reactors were operated at the site.to support these facilities, the River Water System was constructed to provide cooling water to pass through heat exchangers to absorb heat from the reactor core in each of the five reactor areas (C, K, L, P, and R). The DOE Savannah River Strategic Plan directs the SRS to find ways to reduce operating costs and to determine what site infrastructure it must maintain and what infrastructure is surplus. The River Water System has been identified as a potential surplus facility. Three alternatives to reduce the River Water System operating costs are evaluated in this EIS. In addition to the No-Action Alternative, which consists of continuing to operate the River Water System, this EIS examines one alternative (the Preferred Alternative) to shut down and maintain the River Water System in a standby condition until DOE determines that a standby condition is no longer necessary, and one alternative to shut down and deactivate the River Water System. The document provides background information and introduces the River Water System at the SRS; sets forth the purpose and need for DOE action; describes the alternatives DOE is considering; describes the environment at the SRS and in the surrounding area potentially affected by the alternatives addressed and provides a detailed assessment of the potential environmental impacts of the alternatives; and identifies regulatory requirements and evaluates their applicability to the alternatives considered

  20. Influence of nuclear power plants shutdown period in operation of hydrothermic systems

    International Nuclear Information System (INIS)

    Coelho, J.; Pacheco, R.L.; Zuern, H.H.

    1986-01-01

    The impact of the outage need of nuclear power plants for refuelling and maintenance during a critical hydrological period is analysed. The feature of lengthening the useful life of the reactor core charge with resulting reduction in usable power allows certain flexibility in postponing the refuelling and maintenance outage to less critical periods, which reflects on the system reliability performance indices. Simulations with a stochastic energy production model have been made by computing the loss of load probability of a hypothetical power system containing a nuclear power plant under the conditions described above. (Author) [pt

  1. In reactor measurements, modeling and assessments to predict liquid injection shutdown system nozzle to Calandria tube time to contact

    International Nuclear Information System (INIS)

    Kirstein, K.; Kalenchuk, D.

    2011-01-01

    Over the past few years there has been an expanding effort to assess the potential for Calandria Tubes (CTs) coming into contact with Liquid Injection Shutdown System (LISS) Nozzles to ensure continued contact-free operation as required by CSA N285.4. LISS Nozzles (LINs), which run perpendicular to and between rows of fuel channels, sag at a slower rate than the fuel channels. As a result certain LINs may come in contact with CTs above them. The CT/LIN gaps can be predicted from calculated CT sag, LIN sag and a number of component and installation tolerances. This method however results in very conservative predictions when compared to measurements, confirmed with the in reactor measurements initiated in 2000, when gaps were successfully measured the first time using images obtained from a camera-assisted measurement tool inserted into the calandria. To reduce the conservatism of the CT/LIN gap predictions, statistical CT/LIN gap models are used instead. They are derived from a comparison between calculated gaps based on nominal dimensions and the visual image based measured gaps. These reactor specific (typically 95% confidence level) CT/LIN gap models account for all uncertainties and deviations from nominal values. Prediction error margins reduce as more in-reactor gap measurements become available. Each year more measurements are being made using this standardized visual CT/LIN proximity method. The subsequently prepared reactor-specific models have been used to provide time to contact for every channel above the LINs at these stations. In a number of cases it has been used to demonstrate that the reactor can be operated to its end of life before refurbishment with no predicted contact, or specific at-risk channels have been identified for which appropriate remedial actions could be implemented in a planned manner. (author)

  2. High Cycle Thermal Fatigue Analysis for a Mixing Tee in Safety Injection and Shutdown Cooling System of SKN Unit 3 and 4 Power Plant

    International Nuclear Information System (INIS)

    Yang, Kyeong Jin; Lee, Dong Jae; Kim, Dae Soo; Huh, Man Gil

    2011-01-01

    Safety Injection and Shutdown Cooling system (SISC) in a nuclear power plant has an important role of core cooling during plant shutdown and on emergency conditions. A heat exchanger on the SISC removes the heat energy generated in the reactor core during shutdown cooling event. Mixing tee placed on downstream of the heat exchanger designates a Tshaped branch connection where the hot flow passed through the by-pass line mixes with the flow passed through the heat exchanger, and due to the characteristics of fluid with bad heat conductivity, the flow develops a mixing zone in a distance from the mixing tee. The pipe wall in the mixing zone experiences the thermal oscillation of high cycle, and therefore is in a state of the high cycle thermal fatigue loadings. In this work, performed is the high cycle thermal fatigue analysis for a mixing tee under the prescribed thermal loadings in a mixing zone. Using the evaluation guide established by JSME, JSME S017- 2003 which has evaluation procedure composing of the four steps, we evaluate the fatigue integrity of the mixing tee of which the results show that the mixing tee satisfies the fatigue integrity in the last step (fourth) of four steps of evaluation procedure where the fatigue usage factor, U was calculated and then compared with the well known criterion, U<1. Representative results of the fatigue analysis are also discussed

  3. 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.

  4. U.S. Federal Reserve Systems

    Data.gov (United States)

    Department of Homeland Security — This dataset is comprised of forty-five entities that are part of the United States Federal Reserve System according to the United States Department of Treasury. The...

  5. Reserve valuation in electric power systems

    Science.gov (United States)

    Ruiz, Pablo Ariel

    Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

  6. Study on Online Hotel Reservation Systems

    OpenAIRE

    Alleweldt, Frank; Tonner, Klaus; McDonald, Marc

    2009-01-01

    This study, conducted by Civic Consulting, looks at both pre-contractual and contractual matters concerning online hotel reservation systems, examines relevant Community rules, identifies gaps and, where needed, discusses possible policy options. Key conclusions The study shows that the impact of Community law on online hotel

  7. Your Money and the Federal Reserve System.

    Science.gov (United States)

    Federal Reserve Bank of Minneapolis, Minn.

    The booklet explores various roles which money has played throughout history and examines the relationship between money and the Federal Reserve System. The major objective is to increase understanding of the performance of various functions such as making money work as a medium of exchange and as a measure of value and of storing value for future…

  8. 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.)

  9. Analysis of the dynamic behaviour of the PEC shutdown system. Pt. 1. Experimental tests; Pt. 2. Validation of the numerical analysis

    International Nuclear Information System (INIS)

    Bonacina, G.; Franchioni, G.; Zola, M.; Maresca, G.; Martelli, A.

    1988-01-01

    This technical report deals with the experimental research carried out in 1984-1985 by the Dynamic Tests Department of ISMES, Bergamo, Italy, on a mock-up of the Drive Mechanism - Control Rod System (Shutdown Mechanism) of the PEC Sodium Cooled Fast Reactor. The research was sponsored by Ansaldo Divisione NIRA, Genova, Italy, with the cooperation of ENEA, Bologna, Italy, in the frame of the experimental activities in support of the PEC seismic verification. The first part of the report illustrates some aspects particularly related to the experimental details of the research, such as: criteria for the simulation of the actual environment, design of the test rig, tests design, instrumentation and equipment, criteria for test data processing and so on. The second part deals with some aspects of the seismic tests carried out by ISMES on a full scale mock-up of the Drive Mechanism and Control Rod (Shutdown System) of the PEC fast reactor, and the calculations performed by NIRA in order to reproduce the results of these tests, showing the possibility to use the model pointed out, with only a few modifications, to determine the stress level of the mechanism and the scramability of the rod in the reactor. Some comparisons between experimental and numerical results are shown, and the scramability of the rod is demonstrated for different seismic motions. 15 refs, 52 figs

  10. 46 CFR 111.33-7 - Alarms and shutdowns.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

  11. 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

  12. Method for calculating the forces and deformations in the fast reactor fuel assembly accounting for the effects of reactor control system elements and shutdown

    International Nuclear Information System (INIS)

    Likhachev, Yu.I.; Vashlyaev, Yu.N.; Kravchenko, I.N.

    1980-01-01

    Methods for calculating deformations and interaction forces of heat-generating assemblies (HGA) of fast reactor core with account for the effect of control and protection system (CPS) elements at the reactor operation and change of interaction efforts between HGA at the reactor shutdown, are described. The results of testing the suggested methods on example of estimate of HGA behaviour of the BN-350 reactor are presented. For estimating the effect of CPS elements on HGA bending the sector model has been used. It is assumed that HGA deformation inside each sector is independent of HGA deformation of other sectors. A higher calculation accuracy is attained by means of laying out of sectors into regions of preferable influence of emergency protection elements and compensating packets. When determining deformation and interaction efforts between HGA caused by temperature change in the course of shutdown it is supposed that the HGA deformation is purely elastic. The methods described are realized in the form of ABRI-CPS and ABRI-HOL programs written in FORTRAN for the BESM-6 computer. The results of HGA calculations of the BN-350 reactor core show that CPS elements decrease contact efforts in the middle of the central packet, increase contact efforts in the peak of the central packet, increase contact efforts in the peaks of packets from the eight row to the periphery and increase contact efforts in the middles of packets from the 5th to 9th row [ru

  13. 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.)

  14. Shutdown Policies for MEMS-Based Storage Devices -- Analytical Models

    NARCIS (Netherlands)

    Khatib, M.G.; Engelen, Johannes Bernardus Charles; Hartel, Pieter H.

    MEMS-based storage devices should be energy ecient for deployment in mobile systems. Since MEMS-based storage devices have a moving me- dia sled, they should be shut down during periods of inactivity. However, shutdown costs energy, limiting the applicability of aggressive shutdown decisions. The

  15. The Chernobyl plant shutdown

    International Nuclear Information System (INIS)

    2000-12-01

    The Chernobylsk-1 reactor, operational in september 1977 has been stopped in november 1996; the Chernobylsk-2 reactor started in november 1978 is out of order since 1991 following a fire. The Chernobylsk-3 reactor began in 1981. During the last three years it occurs several maintenance operations that stop it. In june 2000, the Ukrainian authorities decided to stop it definitively on the 15. of december (2000). This file handles the subject. it is divided in four chapters: the first one gives the general context of the plant shutdown, the second chapter studies the supporting projects to stop definitively the nuclear plant, the third chapter treats the question of the sarcophagus, and the fourth and final chapter studies the consequences of the accident and the contaminated territories. (N.C.)

  16. 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.

  17. ORAM and shutdown PRA comparison study

    International Nuclear Information System (INIS)

    He, W.G.; Hilsmeier, Todd; Carrier, Tom

    2000-01-01

    A comparison study between results obtained from an Outage Risk Assessment and Management (ORAM) model and a shutdown Probabilistic Risk Analysis (PRA) model was conducted. The purpose of the study was to provide useful risk information for better outage planning by focusing resources and contingency plans on risk significant configurations. The comparison study used selected configurations from the 8th refueling outage of the Hope Creek Generation Station (HCGS), a Boiling Water Reactor (BWR). A total of Eleven configurations were compared. Three configurations were selected to evaluate the impact of the Service Water System during the early stage of a refueling outage. (There are existing studies suggesting that the designed redundancy of Service Water Systems is needed during the early stage of a shutdown.) Four configurations were selected because they were deemed risk significant by the ORAM analysis. (For configurations deemed risk significant by ORAM results, compensatory actions have been taken and contingency plans have been developed to mitigate potential deviations from the configuration. The shutdown PRA was used to evaluate the necessity and effectiveness of these contingency plans and compensatory actions.) To increase the comparison population, an additional four configurations were randomly selected. Thus, a total of 15 configurations were evaluated by the shutdown PRA, and a total of 11 configurations were studied by the ORAM. (author)

  18. Social aspects of reactor shutdowns

    International Nuclear Information System (INIS)

    Breton, A.

    1984-01-01

    Analysis of the problems caused by the sudden change of personnel working in nuclear power plant when shutdowns occured: reception and security of the exterior interveners, organization and logistics, radiosafety, planning of the team works, etc.. [fr

  19. 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.

  20. A Bayesian reliability study on motorized valves for the emergency core cooling, heat transport isolation and shutdown cooling systems at Gentilly-2 Nuclear Generating Station

    International Nuclear Information System (INIS)

    Smith, J.E.; Rennick, D.F.; Nainer, A.

    1996-01-01

    The objective of this is to examine operational data on 32 motorized valves in the emergency core cooling, shutdown cooling and heat transport isolation systems and determine if the evidence would support a reduction in testing frequency of these valves. The methodology used is to examine the data which has accumulated on motorized valve failures since Gentilly-2 first entered service, compare these data with similar data from other sources, and determine whether the evidence indicate that demand-based, wear out type failure mechanisms play a significant role in the recorded failures. The statistical data are then updated, using a Bayesian updating procedure, to obtain revised time based failure rates and demand based probabilities of failure on demand for the motorized valves. The revised failure rates and probabilities are then applied to the fault tree models for the systems of interest to determine what effects there would be, with the current test intervals and with extended test intervals, on the probability of failure of the systems. (author)

  1. 46 CFR 153.296 - Emergency shutdown stations.

    Science.gov (United States)

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.296 Emergency shutdown stations. (a) Each tankship must have at...

  2. Changing the VP Reserve Readiness System to Match the Crew-Coordination Requirements of Reserve Aircrews

    National Research Council Canada - National Science Library

    Woods, William

    1997-01-01

    .... The current VP readiness system promotes long-term, fixed crews with TACNUC rules. Adhering to these crew composition rules can cause considerable scheduling difficulties for reserve squadrons...

  3. 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)

  4. Definition and means of maintaining the supply ventilation system seismic shutdown portion of the PFP safety envelope. Revision 2

    International Nuclear Information System (INIS)

    Keck, R.D.

    1995-01-01

    This report describes the modifications to the ventilation system for the Plutonium Finishing Plant. Topics discussed in this report include; system functional requirements, evaluations of equipment, a list of drawings showing the safety envelope boundaries; list of safety envelope equipment, functional requirements for individual safety envelope equipment, and a list of the operational, maintenance and surveillance procedures necessary to operate and maintain the system equipment

  5. Technical Assessment: WRAP 1 HVAC Passive Shutdown

    International Nuclear Information System (INIS)

    Ball, D.E.; Nash, C.R.; Stroup, J.L.

    1993-01-01

    As the result of careful interpretation of DOE Order 6430.lA and other DOE Orders, the HVAC system for WRAP 1 has been greatly simplified. The HVAC system is now designed to safely shut down to Passive State if power fails for any reason. The fans cease functioning, allowing the Zone 1 and Zone 2 HVAC Confinement Systems to breathe with respect to atmospheric pressure changes. Simplifying the HVAC system avoided overdesign. Construction costs were reduced by eliminating unnecessary equipment. This report summarizes work that was done to define the criteria, physical concepts, and operational experiences that lead to the passive shutdown design for WRAP 1 confinement HVAC systems

  6. Technical Assessment: WRAP 1 HVAC Passive Shutdown

    Energy Technology Data Exchange (ETDEWEB)

    Ball, D.E.; Nash, C.R.; Stroup, J.L.

    1993-08-12

    As the result of careful interpretation of DOE Order 6430.lA and other DOE Orders, the HVAC system for WRAP 1 has been greatly simplified. The HVAC system is now designed to safely shut down to Passive State if power fails for any reason. The fans cease functioning, allowing the Zone 1 and Zone 2 HVAC Confinement Systems to breathe with respect to atmospheric pressure changes. Simplifying the HVAC system avoided overdesign. Construction costs were reduced by eliminating unnecessary equipment. This report summarizes work that was done to define the criteria, physical concepts, and operational experiences that lead to the passive shutdown design for WRAP 1 confinement HVAC systems.

  7. Confirmation of shutdown cooling effects

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Kotaro, E-mail: ksato@nelted.co.jp; Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro [Nuclear Engineering, Limited, 1-3-7 Tosabori Nishi-ku, Osaka-shi, Osaka 550-0001 (Japan)

    2015-12-31

    After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO{sub 2} fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO{sub 2} and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

  8. Confirmation of shutdown cooling effects

    Science.gov (United States)

    Sato, Kotaro; Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro

    2015-12-01

    After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO2 fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO2 and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

  9. Transient Flows in a Pipe System with Pump Shut-Down and the Simultaneous Closing of a Spherical Valve

    Science.gov (United States)

    Zhang, Zh.

    2016-11-01

    Because of the limited value of the wave propagation speed in water the propagation of a pressure surge in transient flows can be tracked in the time series. This enables both the pressure head and the flow velocity in pipe flows to be determined as a function of both the coordinate along the pipe and the time. The propagation of the pressure surge includes both wave transmission and reflection. The latter occurs where the flow section is changed. The wave tracking method has been demonstrated as highly accurate and subsequently was applied to much more complex hydraulic systems, in which the pump is shut off and the spherical valve is simultaneously progressively closed. A combined four-quadrant characteristic of the pump and a spherical valve has been worked out, with which the computational procedure for the transient flow in the complex system could be significantly simplified. It has been demonstrated that not only the pressure surge in the hydraulic system but also the rotational speed of the pump could be satisfactorily computed. The computational algorithm has been demonstrated as quite simple, so that all calculations could be performed simply by means of the Microsoft Excel module.

  10. Nuclear safeguards and nuclear shutdowns

    International Nuclear Information System (INIS)

    Worthington, J.D.

    1976-01-01

    The issues involved in the California nuclear initiative (Proposition 15) are described. Some of the characteristics of the anti-nuclear lobby are outlined. Some do's and don'ts for the nuclear group are listed. The nuclear shutdown effort was concentrated on the safeguards and high-level waste disposal issues

  11. Automatic Robot Safety Shutdown System

    Science.gov (United States)

    Lirette, M.

    1985-01-01

    Robot turned off if acceleration exceeds preset value. Signals from accelerometer on robot arm pass through filter and amplifier, eliminating high-frequency noise and hydraulic-pump pulsations. Data digitized and processed in computer. Unit controls other machines that perform repetitive movements, including rotary tables, tracked vehicles, conveyor lines, and elevators.

  12. 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

  13. 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

  14. Effects of different international fiscal systems on reserves reporting

    International Nuclear Information System (INIS)

    McMichael, C.L.

    1996-01-01

    The effects of international fiscal systems on oil and gas reserves evaluation and reporting, was reviewed. The movement in reserves estimates with changing technical, political and economic conditions, was described. Difficulties associated with the evaluation and booking of reserves is largely due to the confusing duplication of terms. For example, explorationists refer to reserves as an undrilled prospect, while engineers refer to them as producing property. The financial analyst refers to reserves of a company, while governments refer to the reserves of the country. The importance of defining reserves with full knowledge of the specific regulations that govern the reporting of reserves externally, and the internal reporting requirements for business planning purposes, was stressed. 2 refs

  15. Reactor shutdown delays medical procedures

    Science.gov (United States)

    Gwynne, Peter

    2008-01-01

    A longer-than-expected maintenance shutdown of the Canadian nuclear reactor that produces North America's entire supply of molybdenum-99 - from which the radioactive isotopes technetium-99 and iodine-131 are made - caused delays to the diagnosis and treatment of thousands of seriously ill patients last month. Technetium-99 is a key component of nuclear-medicine scans, while iodine-131 is used to treat cancer and other diseases of the thyroid. Production eventually resumed, but only after the Canadian government had overruled the Canadian Nuclear Safety Commission (CNSC), which was still concerned about the reactor's safety.

  16. 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...

  17. Oak Ridge Research reactor shutdown maintenance and surveillance

    International Nuclear Information System (INIS)

    Coleman, G.H.; Laughlin, D.L.

    1991-05-01

    The Department of Energy ordered the Oak Ridge Research Reactor to be placed in permanent shutdown on July 14, 1987. The paper outlines routine maintenance activities and surveillance tests performed April through September, 1990, on the reactor instrumentation and controls, process system, and the gaseous waste filter system. Preparations are being made to transfer the facility to the Remedial Action Program. 6 tabs

  18. Classification system of the mineral reserves and resources of Ukraine

    International Nuclear Information System (INIS)

    Lovinyukov, V.I.

    1998-01-01

    This paper describes the system used to classify the resources and reserves of all minerals and fuels in Ukraine. The classification system is part of an official procedure determined by the Ukrainian State Commission on Reserves. Following preparation of resource estimates the results are registered with the State, which maintains an official inventory of all mineral resources. This paper compares the Ukrainian system to, and finds it compatible with the United Nations International Framework of resource classification. The UN system is based on economics of production and mineability. (author)

  19. The FY2014 Government Shutdown: Economic Effects

    Science.gov (United States)

    2013-11-01

    11 Jeffrey Jones, “U.S. Economic Confidence Continues to Slide Amid Shutdown,” Gallup Economy, October 15... Sachs initially predicted that the shutdown would reduce quarterly growth by 0.2 percentage points per week of its duration. After DOD recalled...furloughed workers, Goldman Sachs reduced its estimate to 0.14 percentage points per week for the remainder of the shutdown.32 They predicted that

  20. Wind power variability and power system reserves in South Africa

    DEFF Research Database (Denmark)

    Sørensen, Poul Ejnar; Litong-Palima, Marisciel; Hahmann, Andrea N.

    2017-01-01

    Variable renewable generation, primarily from wind and solar, introduces new uncertainties in the operation of power systems. This paper describes and applies a method to quantify how wind power development will affect the use of short-term automatic reserves in the future South African power...... system. The study uses a scenario for wind power development in South Africa, based on information from the South African transmission system operator (Eskom) and the Department of Energy. The scenario foresees 5% wind power penetration by 2025. Time series for wind power production and forecasts...... are simulated, and the duration curves for wind power ramp rates and wind power forecast errors are applied to assess the use of reserves due to wind power variability. The main finding is that the 5% wind power penetration in 2025 will increase the use of short-term automatic reserves by approximately 2%....

  1. 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

  2. Intelligent Lane Reservation System for Highway(s)

    OpenAIRE

    Dobre, Ciprian

    2012-01-01

    Highways tend to get congested because of the increase in the number of cars travelling on them. There are two solutions to this. The first one, which is also expensive, consists in building new highways to support the traffic. A much cheaper alternative consists in the introduction of advanced intelligent traffic control systems to manage traffic and increase the efficiency of the already existing highways. Intelligent lane reservation system for highways (ILRSH) is such a software control s...

  3. 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

    important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. Additional conclusions from this evaluation include: The 13 shutdown sites use designs from 4 different suppliers involving 11 different (horizontal and vertical) dry storage systems that would require the use of 9 different transportation cask designs to remove the SNF and GTCC waste from the shutdown sites. Although some changes to transportation certificates of compliance will be required, the SNF at the initial 9 shutdown sites (Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion) is in dual purpose dry storage canisters that can be transported, including a small amount of high-burnup fuel. Most sites indicated that 2-3 years of advance time would be required for its preparations before shipments could begin. Some sites could be ready in less time. As additional sites such as Fort Calhoun, Clinton, Quad Cities, Pilgrim, Oyster Creek, and Diablo Canyon shut down, these sites will be included in updates to the evaluation.

  4. User's guide for the Uranium Ore Reserve Calculation System (URAD)

    International Nuclear Information System (INIS)

    1988-12-01

    The URAD (Uranium Reserves and Data) system consists of four computer programs designed to facilitate the evaluation of uranium ore reserves analysis and the handling of basic uranium assay data. URAD is designed specifically as a training tool for anyone unfamiliar with the methodology, data requirements, and/or general computer applications in the field of uranium ore reserves analysis. However, it can effectively be used in a 'production' environment involving considerable amounts of data. The resulting programs are written in Microsoft FORTRAN (Version 3.1) and may be run on any IBM-compatible microcomputer under DOS 2.1 (or later). Only a basic working knowledge of DOS 2.1 is needed to maintain the system and run the programs. This guide includes the overview of the URAD system, the review of sample data and a complete description of the file structure and sample type formats of the basic sample data files. Program URDAT explains the initial processing of the primary UDAT files to obtain standard output listings and gamma-log interpretations of radiometric data, and to create intermediate UDAT files which are used by the ore reserves programs - RESUV, ORSAC, and SCOR. Figs and tabs

  5. Technical Specification action statements requiring shutdown

    International Nuclear Information System (INIS)

    Mankamo, T.; Kim, I.S.; Samanta, P.K.

    1993-11-01

    When safety systems fail during power operation, the limiting conditions for operation (LCOs) and associated action statements of technical specifications typically require that the plant be shut down within the limits of allowed outage time (AOT). However, when a system needed to remove decay heat, such as the residual heat removal (RHR) system, is inoperable or degraded, shutting down the plant may not necessarily be preferable, from a risk perspective, to continuing power operation over a usual repair time, giving priority to the repairs. The risk impact of the basic operational alternatives, i.e., continued operation or shutdown, was evaluated for failures in the RHR and standby service water (SSW) systems of a boiling-water reactor (BWR) nuclear power plant. A complete or partial failure of the SSW system fails or degrades not only the RHR system but other front-line safety systems supported by the SSW system. This report presents the methodology to evaluate the risk impact of LCOs and associated AOT; the results of risk evaluation from its application to the RHR and SSW systems of a BWR; the findings from the risk-sensitivity analyses to identify alternative operational policies; and the major insights and recommendations to improve the technical specifications action statements

  6. 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

  7. Primary reserve studies for high wind power penetrated systems

    DEFF Research Database (Denmark)

    Das, Kaushik; Altin, Müfit; Hansen, Anca Daniela

    2015-01-01

    load shedding. The impact of low inertia caused due to displacement of conventional generators by wind penetration on the power system frequency is investigated in this paper. The possibilities of improving frequency with increase in primary reserve supplied from conventional generators are analyzed....... This paper further explores the capabilities of wind turbines to provide support during underfrequency to prevent load shedding. Maximum wind penetration possible without causing load shedding following a large disturbance is also investigated....

  8. SCPR: Secure Crowdsourcing-Based Parking Reservation System

    Directory of Open Access Journals (Sweden)

    Changsheng Wan

    2017-01-01

    Full Text Available The crowdsourcing-based parking reservation system is a new computing paradigm, where private owners can rent their parking spots out. Security is the main concern for parking reservation systems. However, current schemes cannot provide user privacy protection for drivers and have no key agreement functions, resulting in a lot of security problems. Moreover, current schemes are typically based on the time-consuming bilinear pairing and not suitable for real-time applications. To solve these security and efficiency problems, we present a novel security protocol with user privacy called SCPR. Similar to protocols of this field, SCPR can authenticate drivers involved in the parking reservation system. However, different from other well-known approaches, SCPR uses pseudonyms instead of real identities for providing user privacy protection for drivers and designs a novel pseudonym-based key agreement protocol. Finally, to reduce the time cost, SCPR designs several novel cryptographic algorithms based on the algebraic signature technique. By doing so, SCPR can satisfy a number of security requirements and enjoy high efficiency. Experimental results show SCPR is feasible for real world applications.

  9. Wind Farms’ Spatial Distribution Effect on Power System Reserves Requirements

    DEFF Research Database (Denmark)

    Sørensen, Poul Ejnar; Cutululis, Nicolaos Antonio

    2010-01-01

    The wind power development during last millennium was typically based on small wind turbines dispersed over large areas, leading to a significant smoothing of the wind power fluctuations in a power system balancing area. The present development goes towards much larger wind farms, concentrated...... in smaller areas, which causes the total wind power fluctuations in power system areas to increase significantly. The impact of future large wind farms spatial distribution with respect to the power system reserve requirements is analyzed in this paper. For this purpose, Correlated Wind (CorWind) power time...... series simulation model developed to simulate wind power variability over a large area is used. As a study case, two scenarios for short term offshore wind power development in the West Danish power system region are used. The first scenario assumes that all the wind farms are built in the region...

  10. 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

  11. 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)

  12. National monetary policy by regional design: the evolving role of the Federal Reserve banks in Federal Reserve System policy

    OpenAIRE

    David C. Wheelock

    1999-01-01

    This paper examines the history of Federal Reserve Bank input into Federal Reserve System monetary policymaking. From the Fed's founding in 1914 through the Great Depression, the Reserve Banks held the balance of power. Dissatisfaction with the Fed's performance, however, led to a wholesale reorganization in 1935 that greatly enhanced the authority of the Federal Reserve Board, but retained a role for the Federal Banks through the membership of their presidents on the FOMC, as well as in sett...

  13. 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

  14. The deep hydrogeologic flow system underlying the Oak Ridge Reservation

    International Nuclear Information System (INIS)

    Nativ, R.; Hunley, A.E.

    1993-07-01

    The deep hydrogeologic system underlying the Oak Ridge Reservation contains some areas contaminated with radionuclides, heavy metals, nitrates, and organic compounds. The groundwater at that depth is saline and has previously been considered stagnant. On the basis of existing and newly collected data, the nature of flow of the saline groundwater and its potential discharge into shallow, freshwater systems was assessed. Data used for this purpose included (1) spatial and temporal pressures and hydraulic heads measured in the deep system, (2) hydraulic parameters of the formations in question, (3) spatial temperature variations, and (4) spatial and temporal chemical and isotopic composition of the saline groundwater. In addition, chemical analyses of brine in adjacent areas in Tennessee, Kentucky, Ohio, Pennsylvania, and West Virginia were compared with the deep water underlying the reservation to help assess the origin of the brine. Preliminary conclusions suggest that the saline water contained at depth is old but not isolated (in terms of recharge and discharge) from the overlying active and freshwater-bearing units. The confined water (along with dissolved solutes) moves along open fractures (or man-made shortcuts) at relatively high velocity into adjacent, more permeable units. Groundwater volumes involved in this flow probably are small

  15. 40 CFR 63.1111 - Startup, shutdown, and malfunction.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures for...

  16. 77 FR 60107 - National Estuarine Research Reserve System

    Science.gov (United States)

    2012-10-02

    .... The Rookery Bay Reserve takes an integrated approach to management, linking research, education... catastrophic change events. The Reserve's Environmental Learning Center provides excellent visitor education... Kachemak Bay Reserve takes an integrated approach to management by linking research, education, and...

  17. Development and study of a control and reactor shutdown device for FBR-type reactors with a modified open core

    International Nuclear Information System (INIS)

    Goswami, S.

    1983-01-01

    The doctoral thesis at hand presents a newly designed control and shutdown device to be used for output control and fast shutdown of modified open core FBR-type reactors. The task was the design of a new control and shutdown device having economic and operation advantages, using reactor components time-tested under reactor conditions. This control and shutdown device was adapted to the specific needs concerning dimensions and design. The actuation is based on the magnetic-jack principle, which has been upgraded for the purpose. The principle is now combined with pneumatic acceleration. The improvements mainly concern a smaller number of piece parts and system simplification. (orig./RW) [de

  18. Evaluation of the safety margins during shutdown for NPP Krsko

    International Nuclear Information System (INIS)

    Bencik, V.; Sadek, S.; Bajs, T.

    2004-01-01

    In the paper the results of RELAP5/mod3.3 calculations of critical parameters during shutdown for NPP Krsko are presented. Conservative evaluations have been performed at NPP Krsko to determine the minimum configuration of systems required for the safe shutdown operation. Critical parameters in these evaluations are defined as the time to start of the boiling and the time of the core dry-out. In order to have better insight into the available margins, the best estimate code RELAP5/mod3.3 has been used to calculate the same parameters. The analyzed transient is the loss of the Residual Heat Removal (RHR) system, which is used to remove decay heat during shutdown conditions. Several configurations that include open and closed Reactor Coolant System (RCS) were considered in the evaluation. The RELAP5/mod3.3 analysis of the loss of the RHR system has been performed for the following cases: 1) RCS closed and water solid, 2) RCS closed and partially drained, 3) Pressurizer manway open, Steam Generator (SG) U tubes partially drained, 4) Pressurizer and SG manways open, SG U tubes completely drained, 5) Pressurizer manway open, SGs drained, SG nozzle dams installed and 6) SG nozzle dams installed, pressurizer manway open, 1 inch break at RHR pump discharge in the loop with pressurizer. Both RHR trains were assumed in operation prior to start of the transient. The maximum average steady state temperature for all analyzed cases was limited to 333 K. (author)

  19. 78 FR 53732 - National Estuarine Research Reserve System

    Science.gov (United States)

    2013-08-30

    ... including climate change, threats to reserve resources and ecological functions, watershed development, and... reserve to serve as a model site for sustainable community stewardship. Notable changes in the revised... facility development to support reserve operations. The Grand Bay Reserve takes an integrated approach to...

  20. 78 FR 26617 - National Estuarine Research Reserve System

    Science.gov (United States)

    2013-05-07

    ... including climate change, threats to reserve resources and ecological functions, watershed development, and... reserve to serve as a model site for sustainable community stewardship. Notable changes in the revised... facility development to support reserve operations. The Grand Bay Reserve takes an integrated approach to...

  1. 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.

  2. 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

    visits. Every site was found to have at least one off-site transportation mode option for removing its UNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. Additional conclusions from this evaluation include: The 12 shutdown sites use designs from 4 different suppliers involving 9 different (horizontal and vertical) dry storage systems that would require the use of 8 different transportation cask designs to remove the UNF and GTCC waste from the shutdown sites; Although there are common aspects, each site has some unique features and/or conditions; Although some regulatory actions will be required, all UNF at the initial 9 shutdown sites (Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion) is in licensed systems that can be transported, including a small amount of high-burnup fuel; Each site indicated that 2-3 years of advance time would be required for its preparations before shipments could begin; Most sites have more than one transportation option, e.g., rail, barge, or heavy haul truck, as well as constraints and preferences. It is expected that additional site visits will be conducted to add to the information presented in the evaluation.

  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. Structure and Functions of the Federal Reserve System

    National Research Council Canada - National Science Library

    Smale, Pauline

    2005-01-01

    .... The Federal Reserve formulates the nation's monetary policy, supervises and regulates banks, and provides a variety of financial services to depository financial institutions and the federal government...

  5. The 2013 US Government Shutdown (#Shutdown) and health: an emerging role for social media.

    Science.gov (United States)

    Merchant, Raina M; Ha, Yoonhee P; Wong, Charlene A; Schwartz, H Andrew; Sap, Maarten; Ungar, Lyle H; Asch, David A

    2014-12-01

    In October 2013, multiple United States (US) federal health departments and agencies posted on Twitter, "We're sorry, but we will not be tweeting or responding to @replies during the shutdown. We'll be back as soon as possible!" These "last tweets" and the millions of responses they generated revealed social media's role as a forum for sharing and discussing information rapidly. Social media are now among the few dominant communication channels used today. We used social media to characterize the public discourse and sentiment about the shutdown. The 2013 shutdown represented an opportunity to explore the role social media might play in events that could affect health.

  6. 75 FR 65613 - National Estuarine Research Reserve System

    Science.gov (United States)

    2010-10-26

    ... reserve; and the plans for future land acquisition and facility development to support reserve operations... decision makers; and added significant monitoring of emergent marsh vegetation, invasive species, water... headquarters building with a 4500 square foot structure to support research, stewardship, and the coastal...

  7. 75 FR 49887 - National Estuarine Research Reserve System

    Science.gov (United States)

    2010-08-16

    ... marsh, cobble beaches, and both hard and soft substrate submerged lands. The island is considered a... salt marsh habitat. The 128 acre Ballard Property on Prudence Island consists of forested land with... the reserve; and the plans for future land acquisition and facility development to support reserve...

  8. Control and shutdown mechanism operating experience of TAPS

    International Nuclear Information System (INIS)

    Bhasin, B.K.; Upadhyaya, T.C.

    1997-01-01

    Tarapur Atomic Power Station is one of the oldest operating GE, BWR units in the world. There are two independent types of reactivity control mechanisms to shutdown the reactor, namely fast acting CRD system and the slow acting liquid poison system in the event of any abnormal situations. The fast acting CRD system is also capable of maneuvering the reactor power. An effort is made here to highlight the features of these control mechanisms. This paper also describes valuable operating experiences and challenges faced in maintaining its availability and reliability. (author)

  9. Acceptability of local boiling during shutdown heat removal

    International Nuclear Information System (INIS)

    Dunn, F.E.

    1985-01-01

    Failures in the shutdown heat removal system of an LMFBR might lead to flow stagnation and coolant boiling in the reactor core. At normal operating power, the onset of sodium boiling will lead to film dryout and melting of the cladding and fuel within a few seconds. On the other hand, both calculations and currently available experimental data indicate that at neat fluxes corresponding to decay heat power levels, boiling leads to improved heat removal; and it limits the temperature rise in the fuel pins. Therefore, when setting criteria for decay heat removal systems, there is no reason to preclude sodium boiling per se because of heat removal considerations

  10. Quality assurance program plan fuel supply shutdown project

    International Nuclear Information System (INIS)

    Metcalf, I.L.

    1998-01-01

    This Quality Assurance Program plan (QAPP) describes how the Fuel Supply Shutdown (FSS) project organization implements the quality assurance requirements of HNF-MP-599, Project Hanford Quality Assurance Program Description (QAPD) and the B and W Hanford Company Quality Assurance Program Plan (QAPP), FSP-MP-004. The QAPP applies to facility structures, systems, and components and to activities (e.g., design, procurement, testing, operations, maintenance, etc.) that could affect structures, systems, and components. This QAPP also provides a roadmap of applicable Project Hanford Policies and Procedures (PHPP) which may be utilized by the FSS project organization to implement the requirements of this QAPP

  11. APT Blanket System Loss-of-Flow Accident (LOFA) Analysis Based on Initial Conceptual Design - Case 1: with Beam Shutdown and Active RHR

    International Nuclear Information System (INIS)

    Hamm, L.L.

    1998-01-01

    This report is one of a series of reports that document normal operation and accident simulations for the Accelerator Production of Tritium (APT) blanket heat removal system. These simulations were performed for the Preliminary Safety Analysis Report

  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. 75 FR 59696 - National Estuarine Research Reserve System

    Science.gov (United States)

    2010-09-28

    ... for future land acquisition and facility development to support reserve operations. The objectives... management plan calls for a boundary expansion of 156 acres. The lands consist of one 128 acre parcel on the... acre Dyer Island. Dyer Island habitats include coastal brush, salt marsh, cobble beaches, and both hard...

  14. 76 FR 16620 - National Estuarine Research Reserve System

    Science.gov (United States)

    2011-03-24

    ... plans for future land acquisition and facility development to support reserve operations. The objectives... information to key decisionmakers; and added significant monitoring of emergent marsh vegetation, water... maritime forest, coastal shrub, wetlands, tidal marshes and sand beaches. The property provides important...

  15. 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

  16. Petroleum reserves and undiscovered resources in the total petroleum systems of Iraq: Reserve growth and production implications

    Science.gov (United States)

    Verma, M.K.; Ahlbrandt, T.S.; Al-Gailani, M.

    2004-01-01

    Iraq is one of the world's most petroleum-rich countries and, in the future, it could become one of the main producers. Iraq's petroleum resources are estimated to be 184 billion barrels, which include oil and natural gas reserves, and undiscovered resources. With its proved (or remaining) reserves of 113 billion barrels of oil (BBO) as of January 2003, Iraq ranks second to Saudi Arabia with 259 BBO in the Middle East. Iraq's proved reserves of 110 trillion cubic feet of gas (TCFG) rank tenth in the world. In addition to known reserves, the combined undiscovered hydrocarbon potential for the three Total Petroleum Systems (Paleozoic, Jurassic, and Cretaceous/Tertiary) in Iraq is estimated to range from 14 to 84 BBO (45 BBO at the mean), and 37 to 227 TCFG (120 TCFG at the mean). Additionally, of the 526 known prospective structures, some 370 remain undrilled. Petroleum migration models and associated geological and geochemical studies were used to constrain the undiscovered resource estimates of Iraq. Based on a criterion of recoverable reserves of between 1 and 5 BBO for a giant field, and more than 5 BBO for a super-giant, Iraq has 6 super-giant and 11 giant fields, accounting for 88% of its recoverable reserves, which include proved reserves and cumulative production. Of the 28 producing fields, 22 have recovery factors that range from 15 to 42% with an overall average of less than 30%. The recovery factor can be increased with water injection, improved and enhanced oil recovery methods (IOR and EOR) in various reservoirs, thus potentially increasing Iraq's reserves by an additional 50 to 70 BBO. Reserve growth is a significant factor that has been observed, to some extent, in nearly all Iraqi oil fields. Historically, producing fields have shown an average growth of 1.6 fold (or 60%) in their recoverable reserves over a 20-year period (1981-2001). With periodic assessments of reservoirs, application of available technology, and an upgrading of facilities

  17. Oak Ridge Research Reactor shutdown maintenance and surveillance

    International Nuclear Information System (INIS)

    Coleman, G.H.; Laughlin, D.L.

    1990-10-01

    The Department of Energy ordered the Oak Ridge Research Center Reactor to be placed in permanent shutdown on July 14, 1987. Maintenance activities, both mechanical and instrument, were essentially routine in nature. The performance of the instrumentation for the facility was satisfactory, and maintenance required is provided. The performance of the process system was satisfactory, and maintenance required is indicated. The results of efficiency tests of the various gaseous-waste filters have been summarized and preparations for transfer of the facility to the remedial action program is also indicated

  18. A Sanctuary for Science: The Hastings Natural History Reservation and the Origins of the University of California's Natural Reserve System.

    Science.gov (United States)

    Alagona, Peter S

    2012-01-01

    In 1937 Joseph Grinnell founded the University of California's (U.C.) first biological field station, the Hastings Natural History Reservation. Hastings became a center for field biology on the West Coast, and by 1960 it was serving as a model for the creation of additional U.C. reserves. Today, the U.C. Natural Reserve System (NRS) is the largest and most diverse network of university-based biological field stations in the world, with 36 sites covering more than 135,000 acres. This essay examines the founding of the Hastings Reservation, and asks how it managed to grow and develop, in the 1940s and 1950s, during a time of declining support for natural history research. It shows how faculty and staff courted the support of key institutional allies, presented themselves as the guardians of a venerable tradition in nature study, and emphasized the station's capacity to document ecological change and inform environmental policy and management. In the years since, Hastings and other U.C. reserves have played crucial roles in California environmental politics. Biological field stations in the post-war era deserve more attention not only from historians of biology, but also from environmental historians and other scholars interested in the role of science in society.

  19. 25 CFR 226.28 - Shutdown, abandonment, and plugging of wells.

    Science.gov (United States)

    2010-04-01

    ... production of oil and/or gas has been demonstrated to the satisfaction of the Superintendent. Lessee shall... OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Cessation of Operations § 226.28 Shutdown, abandonment... well. The method of conditioning such well shall be subject to the approval of the Superintendent. (b...

  20. Global shutdown dose rate maps for a DEMO conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Leichtle, D., E-mail: dieter.leichtle@f4e.europa.eu [Karlsruhe Institute of Technology KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Pereslavtsev, P. [Karlsruhe Institute of Technology KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Sanz, J.; Catalan, J.P.; Juarez, R. [Universidad Nacional de Educación a Distancia(UNED), E.T.S. Ingenieros Industriales, C/ Juan del Rosal 12, 28040 Madrid (Spain)

    2015-10-15

    Highlights: • Application of R2S-method on high-resolution full torus sector mesh for DEMO. • Absorbed dose rates after shutdown for a variely of RH equipment at typical locations. • Idenification of radiation levels at several port based locations. - Abstract: For the calculations of highly reliable shutdown dose rate (SDR) maps in fusion devices like a DEMO plant, the Rigorous-2-step (R2S) method is nowadays routinely applied using high-resolution decay gamma sources from initial high-resolution neutron flux meshes activating all materials in the system. This approach has been utilized in the present paper with the objective to provide SDR results relevant for RH systems of a conceptual DEMO design developed in the EU. The primary objective was to assess specific locations of interest for RH equipment inside the vessel and along the extension of maintenance ports. To this end, a provisional DEMO MCNP model has been used, featuring HCLL-type blankets, tungsten/copper divertor, manifolds, vacuum vessel with ports and toroidal field coils. The operational scenario assumed 2.1 GW fusion power and a life-time of 20 years with plant availability of 30%, where removable parts will be extracted after 5.2 years. Results of absorbed dose rate distributions for several relevant materials are presented and discussed in terms of the different contributions from the various activated components.

  1. Evolution of Shutdown Chemistry During Refueling Outage 9 in Yonggwang Unit 4

    International Nuclear Information System (INIS)

    Reactor coolant shutdown chemistry seeks to solubilize corrosion products generated during the operating cycle and remove them via demineralization. This process is induced by proper control of chemistry during the shutdown process and releases elevated levels of radioactivity into the bulk coolant. The solubilization of these radionuclides is significant in that it makes it easier for the radionuclides to be transported to the demineralizer, thereby minimizing the activation of deposited corrosion products and the release of already activated species. For many years, PWR plants have sought to optimize the interplay between shutdown chemistry and plant equipment, often modifying both. Numerous strategies have been developed to reduce radiation fields, personnel exposure, and outage durations. Optimization of shutdown chemistry practices becomes increasingly important due to the current industry interest in safety and plant availability. This paper deals with the evaluation results of shutdown chemistry at Yonggwang unit 4 Refueling 9 for optimizing plant practices. The data gathered by electronic dosimeters and ISOCS (In-Situ Object Counting System) device were also discussed in this paper

  2. Development of Abnormal Operating Strategies for Station Blackout in Shutdown Operating Mode in Pressurized Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Duk-Joo; Lee, Seung-Chan; Sung, Je-Joong; Ha, Sang-Jun [KHNP CRI, Daejeon (Korea, Republic of); Hwang, Su-Hyun [FNC Tech. Co., Yongin (Korea, Republic of)

    2016-10-15

    Loss of all AC power is classified as one of multiple failure accident by regulatory guide of Korean accident management program. Therefore we need develop strategies for the abnormal operating procedure both of power operating and shutdown mode. This paper developed abnormal operating guideline for loss of all AC power by analysis of accident scenario in pressurized water reactor. This paper analyzed the loss of ultimate heat sink (LOUHS) in shutdown operating mode and developed the operating strategy of the abnormal procedure. Also we performed the analysis of limiting scenarios that operator actions are not taken in shutdown LOUHS. Therefore, we verified the plant behavior and decided operator action to taken in time in order to protect the fuel of core with safety. From the analysis results of LOUHS, the fuel of core maintained without core uncovery for 73 minutes respectively for opened RCS states after the SBO occurred. Therefore, operator action for the emergency are required to take in 73 minutes for opened RCS state. Strategy is to cooldown by using spent fuel pool cooling system. This method required to change the plant design in some plant. In RCS boundary closed state, first abnormal operating strategy in shutdown LOUHS is first abnormal operating strategy in shutdown LOUHS is to remove the residual heat of core by steam dump flow and auxiliary feedwater of SG.

  3. Hazard Classification for Fuel Supply Shutdown Facility

    International Nuclear Information System (INIS)

    BENECKE, M.W.

    2000-01-01

    Final hazard classification for the 300 Area N Reactor fuel storage facility resulted in the assignment of Nuclear Facility Hazard Category 3 for the uranium metal fuel and feed material storage buildings (303-A, 303-B, 303-G, 3712, and 3716). Radiological for the residual uranium and thorium oxide storage building and an empty former fuel storage building that may be used for limited radioactive material storage in the future (303-K/3707-G, and 303-E), and Industrial for the remainder of the Fuel Supply Shutdown buildings (303-F/311 Tank Farm, 303-M, 313-S, 333, 334 and Tank Farm, 334-A, and MO-052)

  4. Improving Deterministic Reserve Requirements for Security Constrained Unit Commitment and Scheduling Problems in Power Systems

    Science.gov (United States)

    Wang, Fengyu

    Traditional deterministic reserve requirements rely on ad-hoc, rule of thumb methods to determine adequate reserve in order to ensure a reliable unit commitment. Since congestion and uncertainties exist in the system, both the quantity and the location of reserves are essential to ensure system reliability and market efficiency. The modeling of operating reserves in the existing deterministic reserve requirements acquire the operating reserves on a zonal basis and do not fully capture the impact of congestion. The purpose of a reserve zone is to ensure that operating reserves are spread across the network. Operating reserves are shared inside each reserve zone, but intra-zonal congestion may block the deliverability of operating reserves within a zone. Thus, improving reserve policies such as reserve zones may improve the location and deliverability of reserve. As more non-dispatchable renewable resources are integrated into the grid, it will become increasingly difficult to predict the transfer capabilities and the network congestion. At the same time, renewable resources require operators to acquire more operating reserves. With existing deterministic reserve requirements unable to ensure optimal reserve locations, the importance of reserve location and reserve deliverability will increase. While stochastic programming can be used to determine reserve by explicitly modelling uncertainties, there are still scalability as well as pricing issues. Therefore, new methods to improve existing deterministic reserve requirements are desired. One key barrier of improving existing deterministic reserve requirements is its potential market impacts. A metric, quality of service, is proposed in this thesis to evaluate the price signal and market impacts of proposed hourly reserve zones. Three main goals of this thesis are: 1) to develop a theoretical and mathematical model to better locate reserve while maintaining the deterministic unit commitment and economic dispatch

  5. Preventing the Shut-Down: Embodied Critical Care in a Teacher Educator's Practice

    Science.gov (United States)

    Trout, Muffet; Basford, Letitia

    2016-01-01

    This article explores the practice of one teacher educator to understand how she mitigates student resistance to prevent what we call "the shut-down" when teaching mostly White students about systemic forms of oppression. Engaging students in conversations about oppression does not in itself disrupt systems of power and privilege in…

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

    International Nuclear Information System (INIS)

    Mueller, C.J.

    1987-01-01

    The uncertainty in predicting the effectiveness of inherent shutdown (ISD) in innovative designs 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 ISD; (2) the approximation of representing all such ATWS events by a selected set of ''generic scenarios''; and (3) the inability to exactly calculate the core response to the selected generic scenarios. In this summary, the methodology and associated results of work used to establish probabilities of failure of inherent shutdown of innovative LMRs to the unprotected loss-of-flow (LOF) accident are discussed

  7. Support method for solving an optimal xenon shutdown problem

    International Nuclear Information System (INIS)

    Dung, L.C.

    1992-01-01

    Since the discovering of the maximum principle by Pontriagin in 1956, methods for solving optimal control problems have been developed fast. There are the efforts to solve an optimal problem of transient process in a nuclear reactor using its ideas. However, the classical maximum principle does not show how to construct an optimal control or suboptimal control with a given exactness. We exploit mainly in the present work the ideas of the support method proposed by Gabasov and Kirillova for linear systems, in order to solve an optimal control problem for non-linear systems. The constructive maximum principle for non-linear dynamic systems with controllable structure received by us in this paper is new result. The ε - maximum principle is used for receiving an 7-phase ε - optimal control of optimal xenon shutdown problem. (author)

  8. The Reserve Component Automation System (RCAS) -- A Case Study in the Evolution of an Information Management System

    National Research Council Canada - National Science Library

    Brady, George

    1998-01-01

    The Reserve Component Automation System (RCAS) is a Wide Area/Local Area Network system designed to provide automation support for the Reserve Components' mobilization management and sustaining-base operations...

  9. Order concerning a nuclear reactor shutdown

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Judgment of the State Administrative Court of Baden Wuerttemberg in head notes including: The authority of the Minister-President to give general guidelines includes the right to issue single directives; in matters of prime political significance he can take measures to realize such aims. - It is no extraneous consideration for the supervisory board under atomic energy law to point out in an order concerning a nuclear reactor shutdown that the disallowed operation of a nuclear plant conflicts with the obligation of the state to provide protection and constitutes a penal offence. Further a discourse on the assignment of discretionary powers under Paragraph 19 Section 3 Clause 2 No. 3 of the Atomic Energy Law. (HSCH) [de

  10. 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...

  11. The Shutdown Dissociation Scale (Shut-D)

    Science.gov (United States)

    Schalinski, Inga; Schauer, Maggie; Elbert, Thomas

    2015-01-01

    The evolutionary model of the defense cascade by Schauer and Elbert (2010) provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages “fright,” “flag,” and “faint,” we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D) was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity). A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups) from healthy controls. The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding. PMID:25976478

  12. The Shutdown Dissociation Scale (Shut-D

    Directory of Open Access Journals (Sweden)

    Inga Schalinski

    2015-05-01

    Full Text Available The evolutionary model of the defense cascade by Schauer and Elbert (2010 provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages “fright,” “flag,” and “faint,” we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity.A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups from healthy controls.The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding.

  13. Estimation of Uncertainles in Gas-Condensate Systems Reserves by Monte Carlo Simulation

    OpenAIRE

    Nagy Stanislaw; Siemek Jakub

    2004-01-01

    In the paper, an impact of improper condensate sampling on calculation of gas and condensate reserves of gas-condensate system is presented. The paper discusses probabilistic methods in reserves estimation (proven, possible, probable). The Peng-Robinson equation of state (EOS) has been used to calculations of phase properties. Sensitivity of CGR during recombination of stream process on liquid and gas reserves has been shown. The large error in estimation of condensate reserve has been obtain...

  14. The management of the state reserving system in the aspect of the regional economic security supporting

    Directory of Open Access Journals (Sweden)

    Aleksandr Yefimovich Zemskov

    2011-06-01

    Full Text Available This paper reviews the role of the state material reserve system to ensure economic security of the region. A classification of reserves ensuring economic security of the region was elaborated. A scheme of systematic and structural representation of the state material reserve in order to improve the economic security of the region was suggested. Optimization of operational control of the territorial offices, factories, and settlements of custody within the framework of the state material reserve is one of the most effective instruments to enhance the functioning of the whole system. To solve the problem of technological processes optimization of products acquisition and storage in manufacturings, plants and points of consignment storage of the state material reserve, a static economic-mathematical model was developed. The results can be used to develop appropriate computer systems for support of effective management decisions in the system of state of material reserve.

  15. Reliability/Cost Evaluation on Power System connected with Wind Power for the Reserve Estimation

    DEFF Research Database (Denmark)

    Lee, Go-Eun; Cha, Seung-Tae; Shin, Je-Seok

    2012-01-01

    Wind power is ideally a renewable energy with no fuel cost, but has a risk to reduce reliability of the whole system because of uncertainty of the output. If the reserve of the system is increased, the reliability of the system may be improved. However, the cost would be increased. Therefore...... the reserve needs to be estimated considering the trade-off between reliability and economic aspects. This paper suggests a methodology to estimate the appropriate reserve, when wind power is connected to the power system. As a case study, when wind power is connected to power system of Korea, the effects...

  16. The Army Selected Reserve Dental Readiness System (ASDRS): Historical Overview, Assessment and Recommendations

    Science.gov (United States)

    2012-05-28

    and the benefits of obtaining dental sealants . 2) Information on how to sign up for the TDP insurance program to achieve maximum dental health...The Army Selected Reserve Dental Readiness System (ASDRS): Historical Overview, Assessment and Recommendations by Colonel...Paper 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER The Army Selected Reserve Dental Readiness System (ASDRS

  17. What's working, what's not: The monitoring and reporting system for Tasmania's national parks and reserves

    Science.gov (United States)

    Glenys Jones

    2015-01-01

    This paper describes the Australian State of Tasmania's management effectiveness Monitoring and Reporting System for national parks and reserves. This jurisdictional performance measurement system is designed to provide all interested parties with reliable factual information and measured evidence about reserve management achievements, progress and challenges. Key...

  18. Estimation of Uncertainles in Gas-Condensate Systems Reserves by Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Nagy Stanislaw

    2004-09-01

    Full Text Available In the paper, an impact of improper condensate sampling on calculation of gas and condensate reserves of gas-condensate system is presented. The paper discusses probabilistic methods in reserves estimation (proven, possible, probable. The Peng-Robinson equation of state (EOS has been used to calculations of phase properties. Sensitivity of CGR during recombination of stream process on liquid and gas reserves has been shown. The large error in estimation of condensate reserve has been obtained. The impact of CGR error on the vapor phase reserve is small.

  19. 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

  20. Final shutdown of Chinon A2

    International Nuclear Information System (INIS)

    Dumont, J.; Pouzac, J.P.

    1987-01-01

    In order to gain a better grasp of the condition of the Chinon plant at shutdown and the problems its operator might have had to deal with had the plant been kept in operation, the authors review: the history of the plant; its technological design; the main problems encountered during its lifetime and how these were solved. In the first instance, the operator took stock of the technical problems which could have affected the safety of the plant or restricted availability in the short and medium term. The analysis did not point to any serious problems for the five years ahead. The periodic economic review of electricity generating capacity carried out in 1983 the Direction de la Production et du Transport d'Electricite de France showed that the optimal date for decommissioning Chinon A2 was July 1985. The fact that this coincided exactly with the transfer date for personnel in this neighbouring units B3 and B4 (2x900 MWe - PWR) was the additional deciding factor for decommissioning in 1985. Taking the decision early enough enabled the operator to optimise the use both of fuel and of reactor staff. The authors then discuss the disposal options for the plant [fr

  1. 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...

  2. Nuclear reactor shutdown control rod assembly

    International Nuclear Information System (INIS)

    Bilibin, K.

    1988-01-01

    This patent describes a nuclear reactor having a reactor core and a reactor coolant flowing therethrough, a temperature responsive, self-actuated nuclear reactor shutdown control rod assembly, comprising: an upper drive line terminating at its lower end with a substantially cylindrical wall member having inner and outer surfaces; a lower drive line having a lower end adapted to be attached to a neutron absorber; a ring movable disposed about the outer surface of the wall member of the upper drive line; thermal actuation means adapted to be in heat exchange relationship with coolant in an associated reactor core and in contact with the ring, and balls located within the openings in the upper drive line. When reactor coolant approaches a predetermined design temperature the actuation means moves the ring sufficiently so that the balls move radially out from the recess and into the space formed by the second portion of the ring thereby removing the vertical support for the lower drive line such that the lower drive line moves downwardly and inserts an associated neutron absorber into an associated reactor core resulting in automatic reduction of reactor power

  3. Theoretical and methodological approaches to the diagnosis of the region's state material reservation system status

    Directory of Open Access Journals (Sweden)

    Aleksandr Anatol'evich Kuklin

    2011-09-01

    Full Text Available This paper reviews the structural components of the state reserve theory with elements of decomposition and tools for studies in separate directions. The system of state material reserve, which includes the following components: economy - people - natural environment - is a necessary and sufficient reserve for their operation and development which is having the ability to respond to short-, medium- and long-term fluctuations in the economy and consider the risks of adverse factors appliance. It was determined that a necessary and sufficient reserve for the operation and development of the region is a major factor in ensuring its economic security. A method of diagnostics for the state material reserve system within the economic security of the region is presented and described. The approbation of the methodological apparatus for the assessment of the state material reserve by the example on the Ural Federal District was done.

  4. 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

  5. Analysis of shutdown and aftercooling cycles of the A-1 nuclear power plant

    International Nuclear Information System (INIS)

    Mueller, V.; Vopatril, M.

    1977-01-01

    A new concept is described of the emergency shut-down and after-cooling of the A-1 reactor based on the elimination of pressure shock and minimization of thermal shock. After-cooling is effected by all circulators which had not been defective before shut-down. During shut-down the pumps run at reduced speed. A diesel generator is used as a self-contained power supply. The after-cooling is classified into three types depending on the machinery power consumption, i.e., normal, emergency and super-emergency. The selection of the power supply and the after-cooling conditions proceeds automatically. A mathematical model is described of A-1 reactor behaviour during different accidents requiring the shut-down and after-cooling. Computer programmes are briefly indicated for the analysis of transients in the primary coolant circuit (ZVJE-73-23, SHOCK A-1), for the analysis of transients resulting from a neutron power controller failure or from a circulator failure (HAZARD), for the analysis of after-cooling processes (DENDEL), and programme SAULIS as an auxiliary programme for processing the results and for the print-out of the DENDEL programme. Steady-state parameters before the failure were found as initial conditions for the calculation of transients. The mathematical model was solved using a system of three computer programmes linked by interprogramme communication. The analysis is described of the cooperation of reactor safety circuits and of the automatic equipment for the reduction of thermal shock in the primary coolant circuit, as is the analysis of reactor accidents related to reactor control and to the safety circuits. Theoretical results are compared with experimental values obtained during the experimental A-1 reactor shut-down and after-cooling. The accuracy of the calculated value for the cooling gas temperature at the central and marginal channel outputs is -10 to +15% during the first 30 s of after-cooling. (J.P.)

  6. 77 FR 65533 - Proposed Information Collection; Comment Request; National Estuarine Research Reserve System...

    Science.gov (United States)

    2012-10-29

    ...) Science Collaborative was created in 2009 to put Reserve-based science to work for coastal communities... Collection; Comment Request; National Estuarine Research Reserve System Science Collaborative Evaluation... funded by the NERRS Science Collaborative are designed to bring the intended users of the science into...

  7. Sensorless Reserved Power Control Strategy for Two-Stage Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    Due to still increasing penetration level of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A reserved power control, where the active power from the PV panels is reserved during operation, is required for grid...

  8. 12 CFR 208.3 - Application and conditions for membership in the Federal Reserve System.

    Science.gov (United States)

    2010-01-01

    ...—(1) Availability of expedited treatment. The expedited membership procedures described in paragraph... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Application and conditions for membership in... GOVERNORS OF THE FEDERAL RESERVE SYSTEM MEMBERSHIP OF STATE BANKING INSTITUTIONS IN THE FEDERAL RESERVE...

  9. Robust Allocation of Reserve Policies for a Multiple-Cell Based Power System

    DEFF Research Database (Denmark)

    Hu, Junjie; Lan, Tian; Heussen, Kai

    2018-01-01

    This paper applies a robust optimization technique for coordinating reserve allocations in multiple-cell based power systems. The linear decision rules (LDR)-based policies were implemented to achieve the reserve robustness, and consist of a nominal power schedule with a series of linear modifica...... in real time operation to make a trade off....

  10. The impact of residential demand response on the costs of a fossil-free system reserve

    DEFF Research Database (Denmark)

    Katz, Jonas; Balyk, Olexandr; Hevia Koch, Pablo Alejandro

    2016-01-01

    In order to achieve a better understanding of the system value of residential demand response, we study the potential impact of flexible demand on the costs of system reserves in a fossil-free electricity supply. Comparing these costs with traditional means of regulation our analysis aims...... to contribute to determining the least-cost options for regulation in a fossil-free power system. We extend an existing energy system model with demand response and reserve modelling and analyse the impact for the case of Denmark in 2035 to reflect a system based on renewable resources for electricity...

  11. 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.

  12. Balancing reserves within a decarbonized European electricity system in 2050. From market developments to model insights

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Casimir [German Institute for Economic Research (DIW Berlin), Berlin (Germany). Dept. of Energy, Transportation, Environment; Univ. of Technology, Berlin (Germany). Workgroup for Infrastructure Policy (WIP)

    2017-03-30

    This paper expands the discussion about future balancing reserve provision to the long-term perspective of 2050. Most pathways for a transformation towards a decarbonized electricity sector rely on very high shares of fluctuating renewables. This can be a challenge for the provision of balancing reserves, although their influence on the balancing cost is unclear. Apart from the transformation of the generation portfolio, various technical and regulatory developments within the balancing framework might further influence balancing costs: i) dynamic dimensioning of balancing reserves, ii) provision by fluctuating renewables or new (battery) storage technologies, and iii) exchange of balancing reserves between balancing zones. The first part of this paper discusses and transforms these developments into quantitative scenario definitions. The second part applies these scenarios to dynELMOD (dynamic Electricity Model), an investment model of the European electricity system that is extended to include balancing reserve provision. In contrast to other models applied in most papers on balancing reserves, this model is capable of evaluating the interdependencies between developments in balancing reserve provision and high shares of fluctuating renewables jointly. The results show that balancing reserve cost can be kept at current levels for a renewable electricity system until 2050, when using a dynamic reserve sizing horizon. Apart from the sizing horizon, storage capacity withholding duration and additional balancing demand from RES are the main driver of balancing costs. Renewables participation in balancing provision is mainly important for negative reserves, while storages play an important role for the provision of positive reserves. However, only on very few occasions, additional storage investments are required for balancing reserve provision, as most of the time sufficient storage capacities are available in the electricity system.

  13. A Sensorless Power Reserve Control Strategy for Two-Stage Grid-Connected PV Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    Due to the still increasing penetration of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A power reserve control, where namely the active power from the PV panels is reserved during operation, is required for grid...... to achieve the power reserve. In this method, the solar irradiance and temperature measurements that have been used in conventional power reserve control schemes to estimate the available PV power are not required, and thereby being a sensorless approach with reduced cost. Experimental tests have been...

  14. Impacts of Contingency Reserve on Nodal Price and Nodal Reliability Risk in Deregulated Power Systems

    DEFF Research Database (Denmark)

    Zhao, Qian; Wang, Peng; Goel, Lalit

    2013-01-01

    The deregulation of power systems allows customers to participate in power market operation. In deregulated power systems, nodal price and nodal reliability are adopted to represent locational operation cost and reliability performance. Since contingency reserve (CR) plays an important role...... and CR allocation. Customers' nodal unit commitment risk and nodal energy interruption have been evaluated through contingency analysis. Customers' reliability cost including reserve service cost and energy interruption cost have also been evaluated....

  15. 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.

  16. Experimental and analytical studies of passive shutdown heat removal from advanced LMRs [liquid metal reactors

    International Nuclear Information System (INIS)

    Pedersen, D.; Heineman, J.; Stewart, R.; Anderson, T.; Lottes, P.; Tessier, J.

    1988-01-01

    A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) has investigated the heat transfer performance of the GE/PRISM passive design. This initial series of experiments simulates the air-side geometry of the PRISM Radiant Reactor Vessel Auxiliary Cooling System (RVACS). The NSTF operates in either a uniform heat flux mode and a uniform temperature mode at the air/guard vessel interface. Analysis of the RVACS performance data indicates excellent agreement with pretest analytical predictions. Correlation analysis presents the heat transfer data in a form suitable for use in LMR design and verification of analytical studies

  17. Measurement of the power trasient and valve closing time, for the zone control system, during a programmed shutdown in August 1989 and its relation with the class IV partial loss event occurred on 27/12/88 in CNE (Embalse nuclear power plant)

    International Nuclear Information System (INIS)

    Paz, A.O. de; Moreno, C.A.; Vinez, J.C.

    1990-01-01

    A description is made of a number of measurements performed during the programmed shutdown on Embalse nuclear power plant (CNE) (August 1989) to validate the existance of a reactivity insertion owing to the emptying of the liquid zone control system. In the event occurred on 27/12/88 when there was a partial loss Cl IV. Once the existance of this contribution was confirmed, the pertinent corrective measures were taken and the test was repeated to verify the effectiveness of the latter. The temporal evolution of a number of neutronic variables and process variables of the liquid zone system were stored in an IBM-PC XT equipped with analog-to-digital converters, for later analysis. (Author) [es

  18. Safety analysis code 'COOLTMP' for assessment of PHT cooling under reactor shutdown conditions

    International Nuclear Information System (INIS)

    Krishna Kumar, P.; Hajela, S.; Datta, D.; Malhotra, P.K.

    2006-01-01

    The thermal energy generated by the reactor core is removed by the Primary Heat Transport (PHT) System when the reactor is under normal operation, by operation of the primary circulation pumps and steam generators. However, when the reactor is shutdown, the decay heat removal is done by the Shut Down (S/D) Cooling heat exchangers and pumps of lower capacity. In the event of loss/stoppage of circulation of PHT under such a situation, the bulk of the decay heat generated will be distributed to the moderator system, end shield system and through the feeders to the feeder cabinet/FM vault environment. However, the PHT inventory in the channel will be heated up because of loss of flow in the channel. The code COOLTMP has been developed to estimate the temperature of PHT following a loss/stoppage of circulation, when the reactor is under shutdown condition. It predicts the increase in the PHT temperature with time for hot channel, average channel or a specific channel under such a condition. It also calculates the apportionment of the decay heat to different heat sinks, viz. moderator, end shield and FM Vault. This computation is required when the plant is required to be under shutdown for doing some maintenance job on the PHT system, feeders or channels where the S/D cooling system has to be stopped and in some cases the headers have to be drained. At that time such a calculation gives whether the peak PHT temperature, or the time available to reach such a temperature, as obtained, is acceptable to carry out such a job. Hence, the schedule of the maintenance job can be decided. This code has been validated for RAPS and MAPS and used extensively for predicting PHT temperature after reactor shutdown to obtain regulatory clearances to stop forced circulation with and without header filled. (author)

  19. The analysis of pressurizer safety valve stuck open accident for low power and shutdown PSA

    International Nuclear Information System (INIS)

    Lim, Ho Gon; Park, Jin Hee; Jang, Seong Chul; Kim, Tae Woon

    2005-01-01

    The PSV (Pressurizer Safety Valve) popping test carried out practically in the early phase of a refueling outage has a little possibility of triggering a test-induced LOCA due to a PSV not fully closed or stuck open. According to a KSNP (Korea Standard Nuclear Power Plant) low power and shutdown PSA (Probabilistic Safety Assessment), the failure of a HPSI (High Pressure Safety Injection) following a PSV stuck open was identified as a dominant accident sequence with a significant contribution to low power and shutdown risks. In this study, we aim to investigate the consequences of the NPP for the various accident sequences following the PSV stuck open as an initiating event through the thermal-hydraulic system code calculations. Also, we search the accident mitigation method for the sequence of HPSI failure, then, the applicability of the method is verified by the simulations using T/H system code

  20. Liberating and regulating of active effect reserves in the Norwegian power system

    International Nuclear Information System (INIS)

    Bakken, Bjoern H.

    2000-01-01

    This report is a summary of the work done in the project ''Active reserves and current control of the effect situation'' in the period 1997 - 99. The project is one of the 7 partial projects in the project '' Operational safety planning and control'' in the Norges forskningsraad's (The Research Council of Norway) EFFEKT program. The aim of the project has been to study and test methods for liberating and regulating active reserves in the Norwegian power system. Traditionally Norway has been rich in effect reserves but in the present deregulated system it will no longer obvious that these reserves are available as the micro economy is more focussed upon in an increasingly pressured operational situation. In the recent years the margins between the available generator effects and the systems maximum load have become increasingly smaller. With the various problems discussed in this report in mind, recommendations may be given with respect to specific measures in order to improve the systems operator possibilities for current control of the effect situation as well as recommendations regarding interesting concepts that ought to be continued in new research projects. The systems operators have implemented some of the proposed measures while others are being studied further. The following specific measures are proposed to the systems operators: 1) To implements graphical survey of the production and the reported reserves in the systems operator EMS tool. 2) To implement tools of the type ''gradual load flow'' in order to prepare possible regulations in critical periods. 3) Reserved instantaneous reserves are introduced as a systems service. 4) The systems operator can reserve effect up to the operational time. 5) Introduce incentives in order to activate the end user more strongly in the ''RK'' market. 5) To modify the methodology corresponding to ''Simultaneous load'' for forecasting bottlenecks in future operation weeks. 6) The systems service ''ramping'' is

  1. A Bilevel Model for Participation of a Storage System in Energy and Reserve Markets

    DEFF Research Database (Denmark)

    Nasrolahpour, Ehsan; Kazempour, Jalal; Zareipour, Hamidreza

    2017-01-01

    We develop a decision-making tool based on a bilevel complementarity model for a merchant price-maker energy storage system to determine the most beneficial trading actions in pool-based markets, including day-ahead (as joint energy and reserve markets) and balancing settlements. The uncertainty...... as reserve commitment (as one of the ancillary services), whereas its balancing product is the energy deployed from the committed reserve. The proposed model captures the interactions of different markets and their impacts on the functioning of the storage system. It also provides an insight for storage...... of net load deviation in real-time is incorporated into the model using a set of scenarios generated from the available forecast in the day-ahead. The objective of this energy storage system is to maximize its expected profit. The day-ahead products of energy storage system include energy as well...

  2. Effects of Computer Reservation System in the Operations of Travel Agencies

    Directory of Open Access Journals (Sweden)

    Sevillia S. Felicen

    2016-11-01

    Full Text Available In travel industry, the main tool used is the computerized booking systems and now known as Global Distribution Systems or GDS. This paper aimed to determine the effect of using Computer Reservation System among Travel Agencies in terms of technical, human and financial aspect. This will help the Internship office to include the identified travel agencies in their linkages where the students will be deployed for internship. The result of this study will also be helpful and can be utilized in the course travel and tour operations with computer reservation system. The descriptive method of research was used with managers and users/staff of 20 travel agencies as participants of the study. Questionnaire was used as main data gathering instrument utilizing percentage, frequency and weighted mean as statistical tool. Abacus System is the computer reservation system used by all travel agencies in Batangas. All travel agencies offered services such as domestic and international hotel reservation, domestic and international ticketing and package tour. The CRS can connect guest to all forms of travel; it has installed built in system security features that can improve agency’s efficiency and productivity.

  3. Impact of marine reserve on maximum sustainable yield in a traditional prey-predator system

    Science.gov (United States)

    Paul, Prosenjit; Kar, T. K.; Ghorai, Abhijit

    2018-01-01

    Multispecies fisheries management requires managers to consider the impact of fishing activities on several species as fishing impacts both targeted and non-targeted species directly or indirectly in several ways. The intended goal of traditional fisheries management is to achieve maximum sustainable yield (MSY) from the targeted species, which on many occasions affect the targeted species as well as the entire ecosystem. Marine reserves are often acclaimed as the marine ecosystem management tool. Few attempts have been made to generalize the ecological effects of marine reserve on MSY policy. We examine here how MSY and population level in a prey-predator system are affected by the low, medium and high reserve size under different possible scenarios. Our simulation works shows that low reserve area, the value of MSY for prey exploitation is maximum when both prey and predator species have fast movement rate. For medium reserve size, our analysis revealed that the maximum value of MSY for prey exploitation is obtained when prey population has fast movement rate and predator population has slow movement rate. For high reserve area, the maximum value of MSY for prey's exploitation is very low compared to the maximum value of MSY for prey's exploitation in case of low and medium reserve. On the other hand, for low and medium reserve area, MSY for predator exploitation is maximum when both the species have fast movement rate.

  4. Economic-environmental energy and reserve scheduling of smart distribution systems: A multiobjective mathematical programming approach

    International Nuclear Information System (INIS)

    Zakariazadeh, Alireza; Jadid, Shahram; Siano, Pierluigi

    2014-01-01

    Highlights: • Environmental/economical scheduling of energy and reserve. • Simultaneous participation of loads in both energy and reserve scheduling. • Aggregate wind generation and demand uncertainties in a stochastic model. • Stochastic scheduling of energy and reserve in a distribution system. • Demand response providers’ participation in energy and reserve scheduling. - Abstract: In this paper a stochastic multi-objective economical/environmental operational scheduling method is proposed to schedule energy and reserve in a smart distribution system with high penetration of wind generation. The proposed multi-objective framework, based on augmented ε-constraint method, is used to minimize the total operational costs and emissions and to generate Pareto-optimal solutions for the energy and reserve scheduling problem. Moreover, fuzzy decision making process is employed to extract one of the Pareto-optimal solutions as the best compromise non-dominated solution. The wind power and demand forecast errors are considered in this approach and the reserve can be furnished by the main grid as well as distributed generators and responsive loads. The consumers participate in both energy and reserve markets using various demand response programs. In order to facilitate small and medium loads participation in demand response programs, a Demand Response Provider (DRP) aggregates offers for load reduction. In order to solve the proposed optimization model, the Benders decomposition technique is used to convert the large scale mixed integer non-linear problem into mixed-integer linear programming and non-linear programming problems. The effectiveness of the proposed scheduling approach is verified on a 41-bus distribution test system over a 24-h period

  5. SNR 2 core dynamics and shut-down signals in a protected loss-of-flow incident

    International Nuclear Information System (INIS)

    Kleefeldt, K.

    1982-01-01

    The dynamic behavior of a 1300 MWe Core during a loss-of-flow incident has been analyzed by use of the SAS3D code for a given pump coast down characteristic and constant core inlet temperature. Emphasis was placed on the questions: How fast and via which monitored parameters can the incident be recognized by the reactor protection system. What is the tolerable time span for the shut-down action without exceeding safety limits. Key prameters and limit values as well as conceivable reactivity feed-back effects are discussed. The result is, that three out of four choosen monitored parameters are capable of initiating a shut-down action in time. In addition, the amount of shut-down reactivity required for a successful scram was briefly investigated

  6. Regulatory and backfit analysis: Unresolved safety issue A-45, shutdown decay heat removal requirements

    International Nuclear Information System (INIS)

    1988-11-01

    All light water reactors require decay heat to be removed subsequent to reactor shutdown. Interruption of the decay heat removal function could lead to severe consequences. Concerns about the reliability of the systems and components that assist in the decay heat removal process and the potentially severe consequences of a complete loss of decay heat removal resulted in establishing the requirements for decay heat removal as an unresolved safety issue (USI) designated USI A-45, ''Shutdown Decay Heat Removal Requirements.'' This report presents the regulatory analysis for USI A-45. It includes (1) a summary of the issue, (2) the proposed technical resolution, (3) alternative resolutions considered by the Nuclear Regulatory Commission, (4) an assessment of the benefits and costs of all alternatives considered, and (5) the decision rationale. 23 refs., 9 figs., 39 tabs

  7. Management of individual and collective dosimetry at Fessenheim nuclear plant. Evaluation after refueling shutdown

    International Nuclear Information System (INIS)

    Lamarre, D.; Waller, A.

    1980-01-01

    The principle of dosimetry management chosen by Fessenheim nuclear power station was originally consisted of two phases: - an automatic acquisition of individual doses realized by stylodosimeter readers; - a deferred data processing by computer. The whole system has not been used during the shutdown for the first refuelling of unit number one in view of encountered difficulties with perfecting of automatic readers prototype, this last phase has been replaced by a manual acquisition of doses. The dosimetry data processing has two main objects: - supervision of individual dosimetry for people who work in the nuclear power station; - knowledge of doses assigned for each working and equipment. Moreover, a first dosimetric result of the shutdown for refuelling of unit number one, enables to notice the workings which doses are the most important and written in percentage of total doses: regulatory controls: about 19%; - steam generators working: 16%; - working decontamination and making health physics screen (lock chamber) 10% [fr

  8. Analysis of failure dependent test, repair and shutdown strategies for redundant trains

    International Nuclear Information System (INIS)

    Uryasev, S.; Samanta, P.

    1994-09-01

    Failure-dependent testing implies a test of a redundant components (or trains) when failure of one component has been detected. The purpose of such testing is to detect any common cause failures (CCFs) of multiple components so that a corrective action such as repair or plant shutdown can be taken to reduce the residence time of multiple failures, given a failure has been detected. This type of testing focuses on reducing the conditional risk of CCFs. Formulas for calculating the conditional failure probability of a two train system with different test, repair and shutdown strategies are developed. A methodology is presented with an example calculation showing the risk-effectiveness of failure-dependent strategies for emergency diesel generators (EDGs) in nuclear power plants (NPPs)

  9. 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)

  10. Cost estimates of operating onsite spent fuel pools after final reactor shutdown

    International Nuclear Information System (INIS)

    Rod, S.R.

    1991-08-01

    This report presents estimates of the annual costs of operating spent fuel pools at nuclear power stations after the final shutdown of one or more onsite reactors. Its purpose is to provide basic spent fuel storage cost information for use in evaluating DOE's reference nuclear waste management system, as well as alternate systems. The basic model of an independent spent fuel storage installation (ISFSI) used in this study was based on General Electric Corporation's Morris Operation and was modified to reflect mean storage capabilities at an unspecified, or ''generic,'' US reactor site. Cost data for the model came from several sources, including both operating and shutdown nuclear power stations and existing ISFSIs. Duke Power Company has estimated ISFSI costs based on existing spent fuel storage costs at its nuclear power stations. Similarly, nuclear material handling facilities such as the Morris Operation, the West Valley Demonstration Project, and the retired Humbolt Bay nuclear power station have compiled spent fuel storage cost data based on years of operating experience. Consideration was given to the following factors that would cause operating costs to vary among pools: (1) The number of spent fuel pools at a given reactor site; (2) the number of operating and shutdown reactors onsite; (3) geographic location; and (4) pool storage capacity. 10 ref., 6 figs., 7 tabs

  11. 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)

  12. Application of PSA to reduce frequency of unplanned shutdown of the reactor

    International Nuclear Information System (INIS)

    Tanipanichskul, P.

    1988-08-01

    The relative importance of all the operating and safety systems of the reactor TRR-1/M1 as well as the major failure modes of the systems are pointed out. The average unavailability of the reactor is 3·3 E-2 per cycle of operation which is in the range value of the actual reactor shutdown recorded during normal operation. Some guidance for annual maintenance and also suggestions for system development to increase safety systems reliability are determined. PSA was applied to improve the safety systems reliability of an operating research reactor. Refs, tabs

  13. Integration of Lithium-Ion Battery Storage Systems in Hydroelectric Plants for Supplying Primary Control Reserve

    Directory of Open Access Journals (Sweden)

    Fabio Bignucolo

    2017-01-01

    Full Text Available The ever-growing diffusion of renewables as electrical generation sources is forcing the electrical power system to face new and challenging regulation problems to preserve grid stability. Among these, the primary control reserve is reckoned to be one of the most important issues, since the introduction of generators based on renewable energies and interconnected through static converters, if relieved from the primary reserve contribution, reduces both the system inertia and the available power reserve in case of network events involving frequency perturbations. In this scenario, renewable plants such as hydroelectric run-of-river generators could be required to provide the primary control reserve ancillary service. In this paper, the integration between a multi-unit run-of-river power plant and a lithium-ion based battery storage system is investigated, suitably accounting for the ancillary service characteristics as required by present grid codes. The storage system is studied in terms of maximum economic profitability, taking into account its operating constraints. Dynamic simulations are carried out within the DIgSILENT PowerFactory 2016 software environment in order to analyse the plant response in case of network frequency contingencies, comparing the pure hydroelectric plant with the hybrid one, in which the primary reserve is partially or completely supplied by the storage system. Results confirm that the battery storage system response to frequency perturbations is clearly faster and more accurate during the transient phase compared to a traditional plant, since time delays due to hydraulic and mechanical regulations are overpassed. A case study, based on data from an existing hydropower plant and referring to the Italian context in terms of operational constraints and ancillary service remuneration, is presented.

  14. Adequacy of operating reserves for power systems in future european wind power scenarios

    DEFF Research Database (Denmark)

    Das, Kaushik; Litong-Palima, Marisciel; Maule, Petr

    2015-01-01

    operating reserves. To study the effects of these imbalances, anticipated wind scenarios for European power systems are modelled for 2020 and 2030. Wind power forecasts for different time scales and real-time available wind power are modelled. Based on these studies, this paper qualitatively analyzes......Wind power generation is expected to increase in Europe by large extent in future. This will increase variability and uncertainty in power systems. Imbalances caused due to uncertainty in wind power forecast can trigger frequency instability in the system. These imbalances are handled using...... the adequacy of primary and secondary reserves requirements for future European power systems. This paper also discusses the challenges due to the uncertainty in wind power forecasts and their possible solutions for wind installation scenarios for 2020 and 2030....

  15. 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.

  16. 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

  17. Assessment of operation reserves in hydrothermal electric systems with high wind generation

    NARCIS (Netherlands)

    Ramos, Andres; Rivier, Michel; García-González, Javier; Latorre, Jesus M.; Morales Espana, G.

    2016-01-01

    In this paper, we propose a method to analyze the amount of operation reserves procured in a system based on two stages. The first stage is a detailed hourly unit commitment and the second stage is a simulation model with a shorter time period. The method is applied to the Spanish hydrothermal

  18. The Career Job Reservation System. Is the Issuance System Best Serving the Needs of the Air Force?

    Science.gov (United States)

    1990-04-01

    AD-A241 065 (i AIR WAR COLLEGE RESEARCH REPORT THE CAREER JOB RESERVATION SYSTEM- IS THE ISSUANCE SYSTEM BEST SERVING THE NEEDS OF THE AIR FORCE... THE NEEDS OF THE AIR FORCE? by Ernest V. Marshall Lieutenant Colonel, USAF A DEFENSE ANALYTICAL STUDY SUBMITTED TO THE FACULTY IN FULFILLMENT OF THE...EXECUTIVE SUMMARY TITLE: The Career Job Reservation (CJR) Sy3tem--Is it serving the needs of the Air Force? AUTHOR: Ernest V. Marshall, Licutenant

  19. The Army Selected Reserve Dental Readiness System: overview, assessment, and recommendations.

    Science.gov (United States)

    Honey, James R

    2013-06-01

    The Army Selected Reserve Dental Readiness System (ASDRS) is a key dental program directed by the Assistant Secretary of the Army (Manpower & Reserve Affairs) starting in fiscal year 09. The Army National Guard and Army Reserve have steadily implemented ASDRS over the past 3 years as a means to improve the historically abysmal dental readiness of the Army Reserve Component (RC). Dental readiness is essential for sustaining an Army RC Operational Force. ASDRS is a tool for RC commanders to provide contract dental readiness care in support of over 558 thousand nonmobilized Selected Reserve Citizen-Soldiers dispersed throughout the 54 states and U.S. territories, at home station before alert, and if necessary after alert (throughout the Army force generation cycle). This article examines the status of ASDRS implementation, assesses its effectiveness in improving Army RC Dental Readiness, and provides Army leadership recommendations regarding the following focus areas: (1) command emphasis, (2) program execution, and (3) synergy with the Military Health System and Department of Veterans Affairs. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

  20. Reservation Application System Of Private Lesson At Easyspeak Denpasar Based On Web And Android

    Directory of Open Access Journals (Sweden)

    Ferry yudhitama putra

    2016-06-01

    Full Text Available Abstract— English Private lessons institutes are now widely facilitates a person to develop English skills in speaking and writing. Currently the service users private lessons English book private lessons manually, that is by coming directly to the place as well as through the telephone service, but with the operator even then still have difficulties in user validation that requires a long time. To facilitate the user in terms of the reservation, then the system will be built based on web and Android. Development of private lessons reservation application built with PHP and Java programming language using CodeIgniter framework on the web side , while on the Android using Eclipse tools , and MySQL as database storage media . Applications reservation private lessons has several functions to make a reservation time and tutor can be done by the student of Easyspeak and on the side of the tutor application can provide information about the student will be taught , as well as on the side of the operator to provide ease in setting booking private lessons because it computerized not manually as before. Applications reservation private lessons are also equipped with a reminder or reminders are made on the side of Android apps , using alarmmanager system.

  1. Myocardial flow reserve in patients with a systemic right ventricle after atrial switch repair.

    Science.gov (United States)

    Singh, T P; Humes, R A; Muzik, O; Kottamasu, S; Karpawich, P P; Di Carli, M F

    2001-06-15

    The purpose of this study was to assess myocardial blood flow (MBF) and flow reserve in systemic right ventricles (RV) in long-term survivors of the Mustard operation. There is a high prevalence of systemic RV dysfunction and impaired exercise performance in long-term survivors of the Mustard operation. A mismatch between myocardial blood supply and systemic ventricular work demand has been proposed as a potential mechanism. We assessed MBF at rest and during intravenous adenosine hyperemia in 11 long-term survivors of a Mustard repair (age 18+/-5 years, median age at repair 0.7 years, follow-up after repair 17+/-5 years) and 13 healthy control subjects (age 23+/-7 years), using N-13 ammonia and positron emission tomography imaging. There was no difference in basal MBF between the systemic RV of survivors of the Mustard operation and the systemic left ventricle (LV) of healthy control subjects (0.80+/-0.19 vs. 0.74+/-0.15 ml/g/min, respectively, p = NS). However, the hyperemic flows were significantly lower in systemic RVs than they were in systemic LVs (2.34+/-0.0.69 vs. 3.44+/-0.62 ml/g/min respectively, p LVs (2.93+/-0.63 vs. 4.74+/-1.09, respectively, p < 0.01). Myocardial flow reserve is impaired in systemic RVs in survivors of the Mustard operation. This may contribute to systemic ventricular dysfunction in these patients.

  2. 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)

  3. 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.)

  4. 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

  5. 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

  6. Basis for Interim Operation for Fuel Supply Shutdown Facility

    International Nuclear Information System (INIS)

    BENECKE, M.W.

    2003-01-01

    This document establishes the Basis for Interim Operation (BIO) for the Fuel Supply Shutdown Facility (FSS) as managed by the 300 Area Deactivation Project (300 ADP) organization in accordance with the requirements of the Project Hanford Management Contract procedure (PHMC) HNF-PRO-700, ''Safety Analysis and Technical Safety Requirements''. A hazard classification (Benecke 2003a) has been prepared for the facility in accordance with DOE-STD-1027-92 resulting in the assignment of Hazard Category 3 for FSS Facility buildings that store N Reactor fuel materials (303-B, 3712, and 3716). All others are designated Industrial buildings. It is concluded that the risks associated with the current and planned operational mode of the FSS Facility (uranium storage, uranium repackaging and shipment, cleanup, and transition activities, etc.) are acceptable. The potential radiological dose and toxicological consequences for a range of credible uranium storage building have been analyzed using Hanford accepted methods. Risk Class designations are summarized for representative events in Table 1.6-1. Mitigation was not considered for any event except the random fire event that exceeds predicted consequences based on existing source and combustible loading because of an inadvertent increase in combustible loading. For that event, a housekeeping program to manage transient combustibles is credited to reduce the probability. An additional administrative control is established to protect assumptions regarding source term by limiting inventories of fuel and combustible materials. Another is established to maintain the criticality safety program. Additional defense-in-depth controls are established to perform fire protection system testing, inspection, and maintenance to ensure predicted availability of those systems, and to maintain the radiological control program. It is also concluded that because an accidental nuclear criticality is not credible based on the low uranium enrichment

  7. Electric Drive Discrete Control System with Automatic Switching-On Reserve for Autonomous Settlement

    Directory of Open Access Journals (Sweden)

    Tsytovich L.I.

    2015-08-01

    Full Text Available The paper aims at developing of control the water supply system’s electric drives for autonomous settlement. The system provides automatic switching to a reserve control channel at refusal of any of the functional elements of the working regulation channel. Usually, such systems have a test signal generator and analyzer to system response to their impact. This result to an increase in the structural redundancy of the system, increase its cost and increase the requirements for the staff qualification. A specific feature of the system is its ability to self-diagnosis of catastrophic malfunctions of scheme’s components and an automatic switching-on the reserve control channels, without applying any test signals to the whole complex of electrical equipment. Multi-zone integrating regulator with frequency-pulse-width modulation realizes this technical solution. Control system structure and signals timing diagrams are presented. The construction principle of adaptive interval-code synchronization device with improved noise stability to control the voltage regulators serving for smooth start-up of asynchronous motors of water pumps is considered as well. Such solution allowing increase noise stability and reliability work of the system in conditions of limited power electrical networks, which is characteristic for the autonomous settlements. The article may be of interest to specialists in the field of power electronics and information electronics, electric drives and process automation.

  8. Method of disposing of shut-down nuclear power plants

    International Nuclear Information System (INIS)

    Gaiser, H.

    1984-01-01

    A shut-down atomic power plant or a section thereof, particularly the nuclear reactor, is disposed of by sinking it to below ground level by constructing a caisson with cutting edges from the foundations of said plant or section or by excavating a pit therebelow

  9. Safety and regulation aspects of nuclear facilities shutdown

    International Nuclear Information System (INIS)

    Clement, B.

    1977-01-01

    Technical dispositions that safety authorities will accept after shutdown of a nuclear installation and reglementation to use are examined. The different solutions from surveillance and maintenance, after removal of fissile materials and radioactive fluids, to dismantling are discussed especially for reactors. In each case the best solution has to be studied to ensure protection of public health and environment [fr

  10. 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

  11. System-Level Value of a Gas Engine Power Plant in Electricity and Reserve Production

    Directory of Open Access Journals (Sweden)

    Antti Alahäivälä

    2017-07-01

    Full Text Available Power systems require a certain amount of flexibility to meet varying demand and to be able to cope with unexpected events, and this requirement is expected to increase with the emergence of variable power generation. In this paper, we focus on gas engine power plant technology and the beneficial influence its flexible operation can have on a power system. The study introduces the concept of a combined-cycle gas engine power plant (CCGE, which comprises a combination of several gas-fired combustion engines and a steam turbine. The operation of CCGE is then comprehensively analyzed in electricity and reserve production in the South African power system and compared with combined-cycle gas turbine (CCGT technology. Even though CCGE is a form of technology that has already been commercialized, it is rarely considered as a source of flexibility in the academic research. That is the notion providing the motivation for this study. Our core contribution is to show that the flexibility of CCGE can be valuable in power systems. The methodology is based on the unit-level model of the studied system and the solving of a day-ahead unit commitment problem for each day of the simulated 11-year period. The simulation studies reveal how a CCGE is able to offer system flexibility to follow hourly load variations and capacity to provide reserve power effectively.

  12. Study of Demand as Frequency Controlled Reserve in Nordic Power System

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    This paper investigates the efficacy of Demand Frequency Reserve (DFR) in Nordic power system. Heat pump, due to its switching flexibility, less disturbing impacts to customers and promising future in application, is used to represent DFR in the study. Thermodynamics of the heat pump unit...... Transmission System Operator (TSO). Accordingly, two case scenarios are designed for the contingency and normal operation, respectively. The simulation models are implemented in RTDS, by means of which the Hardware In the Loop (HIL) test of the developed frequency response device (SmartBox) is carried out....

  13. Reorienting India's financial system: In conversation with Dr Duvvuri Subbarao, Governor, Reserve Bank of India

    Directory of Open Access Journals (Sweden)

    Vivek Moorthy

    2012-06-01

    Full Text Available Confronted by a slowing economy, the Reserve Bank of India has undertaken steps to revive it. These measures, however, run the risk of worsening current high levels of inflation. This paper examines certain aspects of India's financial system that have contributed to this situation. It argues that unduly low yields on Government bonds have prevented a healthy financial system from developing, with adverse impact upon inflation and other macroeconomic outcomes. It suggests that India should focus far more on domestic, and less on external, financial liberalisation. Specifically, yields on non-market borrowing, such as Provident Fund deposits, should be benchmarked to a low frequency measure of consumer price inflation.

  14. Oak Ridge reactor shutdown maintenance and surveillance quarterly report, July, August, and September 1989

    International Nuclear Information System (INIS)

    Hamrick, T.P.; Coleman, G.H.; Laughlin, D.L.

    1990-06-01

    The Department of Energy ordered the Oak Ridge Reactor to be placed in permanent shutdown on July 14, 1987. Maintenance activities, both mechanical and instrument, were essentially routine in nature. Shutdown activities are discussed for this reporting period

  15. Utility Test Results of a 2-Megawatt, 10-Second Reserve-Power System

    Energy Technology Data Exchange (ETDEWEB)

    BALL,GREG J.; NORRIS,BENJAMIN L.

    1999-10-01

    This report documents the 1996 evaluation by Pacific Gas and Electric Company of an advanced reserve-power system capable of supporting 2 MW of load for 10 seconds. The system, developed under a DOE Cooperative Agreement with AC Battery Corporation of East Troy, Wisconsin, contains battery storage that enables industrial facilities to ''ride through'' momentary outages. The evaluation consisted of tests of system performance using a wide variety of load types and operating conditions. The tests, which included simulated utility outages and voltage sags, demonstrated that the system could provide continuous power during utility outages and other disturbances and that it was compatible with a variety of load types found at industrial customer sites.

  16. Effect of the Online Game Shutdown Policy on Internet Use, Internet Addiction, and Sleeping Hours in Korean Adolescents.

    Science.gov (United States)

    Choi, Jiyun; Cho, Hyunseok; Lee, Seungmin; Kim, Juyeong; Park, Eun-Cheol

    2018-02-09

    Internet addiction has emerged as a major public health problem worldwide. In November 2011, the South Korean government implemented an online game shutdown policy, lasting from 12:00 to 6:00 am, as a means of preventing Internet addiction in adolescents aged 15 or below. This study analyzed the effect of this shutdown policy on adolescent Internet use, addiction, and sleeping hours. We analyzed data collected from the Korea Youth Risk Behavior Web-based Survey from 2011 to 2015. Respondents were divided into two groups by age: aged 15 or below (male = 76,048, female = 66,281) and aged 16 or above (male = 52,568, female = 49,060). A difference-in-difference analysis was used to evaluate the effect of this shutdown policy. In 2012, which is immediately following policy enforcement, daily amount of Internet use (in minutes) decreased more in adolescents affected by the policy (i.e., the aged 15 or below group). However, it steadily increased in 2013, 2014, 2015, and showed no meaningful long-term improvements 4 years after policy implementation (-3.648 minutes in 2012 [p = .001], -3.204 minutes in 2013 [p = .011], -1.140 minutes in 2014 [p = .384], and 2.190 minutes in 2015 [p = .107]). The shutdown policy did not alter Internet addiction or sleeping hours. Interestingly, female adolescents, adolescents with low academic performance, and adolescents with low exercise levels exhibited comparatively stronger and longer lasting initial declines in Internet usage. The shutdown policy had practically insignificant effects in reducing Internet use for target adolescents. Thus, policymakers aiming to reduce or prevent Internet addiction should use different strategies. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  17. 77 FR 73968 - Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards...

    Science.gov (United States)

    2012-12-12

    ... AGENCY 40 CFR Parts 60 and 63 RIN 2060-AR62 Reconsideration of Certain New Source and Startup/Shutdown... ``Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards for Hazardous Air... November 30, 2012, proposed ``Reconsideration of Certain New Source and Startup/Shutdown Issues: National...

  18. Type and timing of childhood maltreatment and severity of shutdown dissociation in patients with schizophrenia spectrum disorder.

    Directory of Open Access Journals (Sweden)

    Inga Schalinski

    Full Text Available Dissociation, particularly the shutting down of sensory, motor and speech systems, has been proposed to emerge in susceptible individuals as a defensive response to traumatic stress. In contrast, other individuals show signs of hyperarousal to acute threat. A key question is whether exposure to particular types of stressful events during specific stages of development can program an individual to have a strong dissociative response to subsequent stressors. Vulnerability to ongoing shutdown dissociation was assessed in 75 inpatients (46 M/29 F, M = 31 ± 10 years old with schizophrenia spectrum disorder and related to number of traumatic events experienced or witnessed during childhood or adulthood. The Maltreatment and Abuse Chronology of Exposure (MACE scale was used to collect retrospective recall of exposure to ten types of maltreatment during each year of childhood. Severity of shutdown dissociation was related to number of childhood but not adult traumatic events. Random forest regression with conditional trees indicated that type and timing of childhood maltreatment could predictably account for 31% of the variance (p < 0.003 in shutdown dissociation, with peak vulnerability occurring at 13-14 years of age and with exposure to emotional neglect followed by various forms of emotional abuse. These findings suggest that there may be windows of vulnerability to the development of shutdown dissociation. Results support the hypothesis that experienced events are more important than witnessed events, but challenge the hypothesis that "life-threatening" events are a critical determinant.

  19. A socio-environmental monitoring system for a UNESCO biosphere reserve.

    Science.gov (United States)

    Lowell, Kim

    2017-11-03

    To identify potentially critical changes in an area's ongoing ability to produce multiple ecosystem services, a monitoring system was designed and implemented for the Mornington Peninsula and Westernport Biosphere Reserve in southeast Australia. The system is underpinned by an "environmental vital signs" (EVS) approach that was adopted to provide early warning of critical changes in human and natural characteristics of the area. The six themes monitored are non-coastal water, land including vegetation, biodiversity, natural heritage, built environment (including human population and economic activity), and coasts. These are monitored for the entire area, and each of its five constituent town council areas. After a critical change in any of these is identified, further investigation is required to identify causal factors and, if required, determine an appropriate response. The system relies on data available from external (third-party) organisations to monitor the natural and human characteristics of the area that were important in its designation as a UNESCO biosphere reserve. Strengths and weaknesses associated with the use of third-party data are discussed. These include adoption of baseline years and data reporting periods for different factors, costs, and data quality.

  20. Fundamentals of Using Battery Energy Storage Systems to Provide Primary Control Reserves in Germany

    Directory of Open Access Journals (Sweden)

    Alexander Zeh

    2016-09-01

    Full Text Available The application of stationary battery storage systems to German electrical grids can help with various storage services. This application requires controlling the charge and discharge power of such a system. For example, photovoltaic (PV home storage, uninterruptible power supply, and storage systems for providing ancillary services such as primary control reserves (PCRs represent battery applications with positive profitability. Because PCRs are essential for stabilizing grid frequency and maintaining a robust electrical grid, German transmission system operators (TSOs released strict regulations in August 2015 for providing PCRs with battery storage systems as part of regulating the International Grid Control Cooperation (IGCC region in Europe. These regulations focused on the permissible state of charge (SoC of the battery during nominal and extreme conditions. The concomitant increased capacity demand oversizing may result in a significant profitability reduction, which can be attenuated only by using an optimal parameterization of the control algorithm for energy management of the storage systems. In this paper, the sizing optimization is achieved and a recommendation for a control algorithm that includes the appropriate parameters for the requirements in the German market is given. Furthermore, the storage cost is estimated, including battery aging simulations for different aging parameter sets to allow for a realistic profitability calculation.

  1. Agent-Based Modelling and Simulation to Assess the Impact of Parking Reservation System

    Directory of Open Access Journals (Sweden)

    Xun-You Ni

    2017-01-01

    Full Text Available With the increasing popularity of smart phones, Parking Reservation System (PRS becomes practical to reduce the travel time in cruising for vacant spaces. The aim of this study is to assess the impact of PRS explicitly. This paper was started with analyzing the processes of cruising for vacant spaces and making parking reservation decisions. The vehicles were divided into two categories: the intelligent vehicles and the regular ones. Only the intelligent vehicles have the ability to make a parking reservation beforehand, while the regular ones have to cruise for vacant spaces. All involved components were treated as different agents, including vehicles, parking lots, network, and management center. Based on this, agent-based simulation was introduced to evaluate the performances of the scenarios with different penetration rates. The simulation results indicate the average travel time increases with the improvement of the penetration rates for the regular vehicles. The assessment method presented in this study would assist in promoting the performances of PRS in urban areas.

  2. Carbon stock assessment of two agroforestry systems in a tropical forest reserve in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Lasco, R.D.; Sales, R.F.; Estrella, R.; Saplaco, S.R.; Castillo, A.S.A.; Cruz, R.V.O.; Pulhin, F.B. [University of Philippines Los Banos, Laguna (Philippines). College of Forestry & Natural Resources Environmental Forestry Programme

    2001-07-01

    Carbon dioxide is the most abundant greenhouse gas (GHG) that causes global warming. Thus, land uses such as an agroforestry system have a significant role in moderating climate change since they can be sources and sinks of carbon. The aim of the study was to generate data on the carbon stocks of two agroforestry systems, specifically a Gmelina arborea-Theobroma cacao multistorey system and an alley cropping system with Gliricidia sepium hedges at the agroforestry research and demonstration area inside a forest reserve in Southern Luzon, Philippines. The multistorey system had a mean biomass of 258 Mg C ha{sup -1} and a carbon density of 185 Mg C ha{sup -1}. Carbon was stored in the various pools in the following order of magnitude: soil > tree biomass (above-ground) > necromass > understorey vegetation > roots. The Gliricidia hedgerow had a biomass density of 3.8 Mg C ha{sup -1}; total carbon density was 93 Mg C ha{sup -1}, of which 92 Mg C ha{sup -1} was in the soil.

  3. 235U Holdup Measurement Program in support of facility shutdown

    International Nuclear Information System (INIS)

    Thomason, R.S.; Griffin, J.C.; Lien, O.G.; McElroy, R.D.

    1991-01-01

    In 1989, the Department of Energy directed shutdown of an enriched uranium processing facility at Savannah River Site. As part of the shutdown requirements, deinventory and cleanout of process equipment and nondestructive measurement of the remaining 235 U holdup were required. The holdup measurements had safeguards, accountability, and nuclear criticality safety significance; therefore, a technically defensible and well-documented holdup measurement program was needed. Appropriate standards were fabricated, measurement techniques were selected, and an aggressive schedule was followed. Early in the program, offsite experts reviewed the measurement program, and their recommendations were adopted. Contact and far-field methods were used for most measurements, but some process equipment required special attention. All holdup measurements were documented, and each report was subjected to internal peer review. Some measured values were checked against values obtained by other methods; agreement was generally good

  4. Investigating Power System Primary and Secondary Reserve Interaction under High Wind Power Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingchen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tan, Jin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Krad, Ibrahim [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yang, Rui [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gevorgian, Vahan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ela, Erik [Electric Power Research Inst. (EPRI), Knoxville, TN (United States)

    2016-12-01

    Power system frequency needs to be maintained close to its nominal value at all times to successfully balance load and generation and maintain system reliability. Adequate primary frequency response and secondary frequency response are the primary forces to correct an energy imbalance at the second-to-minute level. As wind energy becomes a larger portion of the world's energy portfolio, there is an increased need for wind to provide frequency response. This paper addresses one of the major concerns about using wind for frequency regulation: the unknown factor of the interaction between primary and secondary reserves. The lack of a commercially available tool to model this has limited the energy industry's understanding of when the depletion of primary reserves will impact the performance of secondary response or vice versa. This paper investigates the issue by developing a multi-area frequency response integration tool with combined primary and secondary capabilities. The simulation is conducted in close coordination with economical energy scheduling scenarios to ensure credible simulation results.

  5. 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.

  6. Uncertainty reduction requirements in cores designed for passive reactivity shutdown

    International Nuclear Information System (INIS)

    Wade, D.C.

    1988-01-01

    The first purpose of this paper is to describe the changed focus of neutronics accuracy requirements existing in the current US advanced LMR development program where passive shutdown is a major design goal. The second purpose is to provide the background and rationale which supports the selection of a formal data fitting methodology as the means for the application of critical experiment measurements to meet these accuracy needs. 6 refs., 1 fig., 2 tabs

  7. COMPUTING SERVICES DURING THE ANNUAL CERN SHUTDOWN

    CERN Multimedia

    1999-01-01

    CERN will close on Friday 17th December at 17:30, and will reopen on Monday 3rd January at 08:30. As in recent years the Computing Services provided by IT Division will remain available as of Friday 17th at 17:30 but running unattended. The exceptions are the database and dedicated engineering services, which will not be available following agreement with their user communities.This year, however, is rather special because of the Y2K issue and as such an interruption is scheduled.This was decided in order to ensure that services are not affected by any unforeseen Y2K bugs at a time when support is not easily available, and to ensure that all systems can be started cleanly in the year 2000. All user services will be closed at 18:00 on Wednesday 29th December after which backups will be taken overnight, then checked and the systems closed down. NO Computing Services will be available again until CERN reopens at 08:30 on Monday 3rd January. The only exceptions are the networking infrastructure, and the email gat...

  8. LHC Report: finalizing the shutdown activities

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    The maintenance work and other activities scheduled for the LHC technical stop have now been completed and the electrical, quality assurance and powering tests are in full swing.   These hardware tests, or hardware re-commissioning as it is known in the CERN Control Centre, are complete for Sectors 5-6 and 6-7. The re-commissioning process is almost complete in Sectors 7-8 and 8-1, but a problem with the emergency stop safety system last week, and the failure of a turbine in the cryogenic plant at Point 8, mean that the final part of the re-commissioning for these two sectors has been delayed and will be completed this week. Preparations for the re-commissioning in the other 4 sectors are going well, and everything is on schedule for the LHC to restart with beam as planned on 18 February. At the SPS, all the technical stop work and magnet changes have been completed and the machine has been handed over to the Operations Group for the usual set of hardware tests and preparations for beam operation. ...

  9. 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.

  10. Environmental Assessment for Type III Fuel Hydrant System at Grissom Air Reserve Base

    Science.gov (United States)

    2011-10-01

    emissions from  architectural  coatings and asphalt paving operations. Emissions of all criteria pollutants    Grissom Air Reserve Base  3‐7  October 2011...3.4 CULTURAL RESOURCES 3.4.1 EVALUATION CRITERIA Cultural resources include archaeological resources, historic  architectural  or engineering...potable water distribution  system (GARB 2007).    Drinking water is sampled periodically by  bioenvironmental  engineering personnel at various locations

  11. Mineral Resource Information System for Field Lab in the Osage Mineral Reservation Estate

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, H.B.; Johnson, William I.

    1999-04-27

    The Osage Mineral Reservation Estate is located in Osage County, Oklahoma. Minerals on the Estate are owned by members of the Osage Tribe who are shareholders in the Estate. The Estate is administered by the Osage Agency, Branch of Minerals, operated by the U.S. Bureau of Indian Affairs (BIA). Oil, natural gas, casinghead gas, and other minerals (sand, gravel, limestone, and dolomite) are exploited by lessors. Operators may obtain from the Branch of Minerals and the Osage Mineral Estate Tribal Council leases to explore and exploit oil, gas, oil and gas, and other minerals on the Estate. Operators pay a royalty on all minerals exploited and sold from the Estate. A mineral Resource Information system was developed for this project to evaluate the remaining hydrocarbon resources located on the Estate. Databases on Microsoft Excel spreadsheets of operators, leases, and production were designed for use in conjunction with an evaluation spreadsheet for estimating the remaining hydrocarbons on the Estate.

  12. Simulation of the regional groundwater-flow system of the Menominee Indian Reservation, Wisconsin

    Science.gov (United States)

    Juckem, Paul F.; Dunning, Charles P.

    2015-01-01

    A regional, two-dimensional, steady-state groundwater-flow model was developed to simulate the groundwater-flow system and groundwater/surface-water interactions within the Menominee Indian Reservation. The model was developed by the U.S. Geological Survey (USGS), in cooperation with the Menominee Indian Tribe of Wisconsin, to contribute to the fundamental understanding of the region’s hydrogeology. The objectives of the regional model were to improve understanding of the groundwater-flow system, including groundwater/surface-water interactions, and to develop a tool suitable for evaluating the effects of potential regional water-management programs. The computer code GFLOW was used because of the ease with which the model can simulate groundwater/surface-water interactions, provide a framework for simulating regional groundwater-flow systems, and be refined in a stepwise fashion to incorporate new data and simulate groundwater-flow patterns at multiple scales. Simulations made with the regional model reproduce groundwater levels and stream base flows representative of recent conditions (1970–2013) and illustrate groundwater-flow patterns with maps of (1) the simulated water table and groundwater-flow directions, (2) probabilistic areas contributing recharge to high-capacity pumped wells, and (3) estimation of the extent of infiltrated wastewater from treatment lagoons.

  13. Carbon sequestration and nutrient reserves under differen t land use systems

    Directory of Open Access Journals (Sweden)

    Maria Ivanilda Aguiar

    2014-02-01

    Full Text Available This study evaluated the contribution of agroforestry (AFS and traditional systems to carbon sequestration and nutrient reserves in plants, litter and soil. The study was carried out in the semiarid region of Brazil in a long-term experiment on an experimental farm of the goat and sheep section of the Brazilian Agricultural Research Corporation (Embrapa. Two agroforestry systems were investigated: agrosilvopastoral (ASP and forest-pasture areas (SP as well as traditional agriculture management (TM, two areas left fallow after TM (six fallow years - F6 and nine fallow years - F9 and one area of preserved Caatinga vegetation (CAT. Soil, litter and plants were sampled from all areas and the contents of C, N, P, K, Ca and Mg per compartment determined. The AFS (ASP and SP had higher nutrient stocks than the traditional and intermediate stocks compared to the preserved Caatinga. In the ASP, a relevant part of the nutrients extracted by crops is returned to the system by constant inputs of litter, weeding of herbaceous vegetation and cutting of the legume crops. After fallow periods of six and nine years, carbon and nutrient stocks in the compartments soil, litter and herbaceous plants were similar to those of the preserved Caatinga (CAT, but still lower than under natural conditions in the woody vegetation.

  14. Water quality data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP), 1996 - 1998 (NODC Accession 0000789)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality data in 22 reserves in the United States and...

  15. Improving the action requirements of technical specifications: A risk-comparison of continued operation and plant shutdown

    International Nuclear Information System (INIS)

    Kim, I.S.; Samanta, P.K.

    1994-01-01

    When the systems needed to remove decay heat are inoperable or degraded, the risk of shutting down the plant may be comparable to, or even higher than, that of continuing power operation with the equipment inoperable while giving priority to repairs. This concern arises because the plant may not have sufficient capability for removing decay heat during the shutdown. However, Technical Specifications (TSs) often require ''immediate'' shutdown of the plant. In this paper, the authors present risk-based analyses of the various operational policy alternatives available in such situations, with an example application to the standby service water (SSW) system of a BWR. These analyses can be used to define risk-effective requirements for those standby safety systems under discussion

  16. Modelling the fluid structure interaction produced by a waterhammer during shutdown of high-pressure pumps

    International Nuclear Information System (INIS)

    Erath, W.; Nowotny, B.; Maetz, J.

    1999-01-01

    Measurements of an experiment in a pipe system with pump shutdown and valve closing have been performed in the nuclear power plant KRB II (Gundremmingen, Germany). Comparative calculations of fluid and structure including interaction show an excellent agreement with the measured results. Theory and implementation of the fluid structure interaction (FSI) and the results of the comparison are described. The following measurements have been compared with calculations: (1) experiments in Delft, Netherlands to analyse the FSI; and (2) experiment with pump shutdown and valve closing in the nuclear power plant KRB II has been performed. It turns out, that the consideration of the FSI is necessary for an exact calculation of 'soft' piping systems. It has significant application in current waterhammer problems. For example, water column closure, vapour collapse, check valve slamming continues to create waterhammers in the energy industry. An important consequence of the FSI is mostly a significant increase of the effective structural damping. This mitigates - so far in all KED's calculations the FSI has taken into account - an amplification of pipe movements due to pressure waves in resonance with structural eigenvalues. To investigate the integrity of pipe systems pipe stresses are calculated. Taking FSI into account they are reduced by 10-40% in the actual case. (orig.)

  17. 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...

  18. 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...

  19. 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...

  20. Evaluation of Costs for Procuring Reserve Capacity under Deregulated Power System using Multi-Agent Model

    Science.gov (United States)

    Suzuki, Satoshi; Kita, Hiroyuki; Tanaka, Eiichi; Hasegawa, Jun

    In this paper, we assume 2 models for securing reserve capacity. One is “Commitment-based Security Model” and the other is “Reserve Market-based Security Model”. In Commitment-based security model, ISO commits procurement of reserve energy to a particular generation company. Meanwhile, in Reserve market-based security model, ISO procures reserve energy through reserve market. The main object of this research is to investigate which model will be preferable for the viewpoint of consumer's cost. To compare these models, two things are considered in this paper. One is bidding behavior of agents which bids to energy market and reserve market. To consider this, Q-Learning of multi-agent model is used. Also, the Unit Commitment (UC) is considered to calculate generation cost. This is to calculate the cost for securing reserve power more precisely.

  1. Watersheds of the Oak Ridge Reservation in a geographic information system

    International Nuclear Information System (INIS)

    Tauxe, J.

    1998-05-01

    This work develops a comprehensive set of watershed definitions for the entire Oak Ridge Reservation and surrounding area. A stream-ordering system is defined based upon the method proposed by Strahler (1952) and using 1:24,000 scale US Geological Survey (USGS) topographic maps and the locally standard S-16A Map (USGS 1987) as sources for topographic contours and locations of streams as recommended by the Natural Resources Conservation Service (NRCS 1995). For each ordered stream, a contributing watershed or catchment area is delineated and digitized into a geographic information system (GIS), generating over 900 watershed polygons of various orders. This new dataset complements a growing database of georeferenced environmental and cultural data which exist for the Oak Ridge area and are routinely used for socioeconomic and environmental analyses. Because these watersheds are now available in a GIS format, they may be used in a variety of hydrologic analyses, including rainfall/runoff modeling, development of geomorphological parameters, and the modeling of contaminant transport in surface waters. An understanding of the relationships of watersheds to sources of contamination and to administrative and political boundaries is also essential in land use planning and the organization of environmental restoration and waste management activities

  2. Spinning reserve quantification by a stochastic–probabilistic scheme for smart power systems with high wind penetration

    International Nuclear Information System (INIS)

    Khazali, Amirhossein; Kalantar, Mohsen

    2015-01-01

    Highlights: • A stochastic–probabilistic approach is proposed for spinning reserve quantification. • A new linearized formulation integrating reliability metrics is presented. • The framework manages the reserve provided by responsive loads and storage systems. • The proposed method is capable of detaching the spinning reserve for different uses. - Abstract: This paper introduces a novel spinning reserve quantification scheme based on a hybrid stochastic–probabilistic approach for smart power systems including high penetration of wind generation. In this research the required spinning reserve is detached into two main parts. The first part of the reserve is procured to overcome imbalances between load and generation in the system. The second part of the required spinning reserve is scheduled according to the probability of unit outages. In order to overcome uncertainties caused by wind generation and load forecasting errors different scenarios of wind generation and load uncertainties are generated. For each scenario the reserve deployed by different components are taken account as the first part of the required reserve which is used to overcome imbalances. The second part of the required reserve is based on reliability constraints. The total expected energy not supplied (TEENS) is the reliability criterion which determines the second part of the required spinning reserve to overcome unit outage possibilities. This formulation permits the independent system operator to purchase the two different types of reserve with different prices. The introduced formulation for reserve quantification is also capable of managing and detaching the reserve provided by responsive loads and energy storage devices. The problem is formulated as a mixed integer linear programming (MILP) problem including linearized formulations for reliability metrics. Obtained results show the efficiency of the proposed approach compared with the conventional stochastic and deterministic

  3. Study on the performance of the Particle Identification Detectors at LHCb after the LHC First Long Shutdown (LS1)

    CERN Document Server

    Fontana, Marianna

    2016-01-01

    During the First Long Shutdown (LS1), the LHCb experiment has introduced major modification in the data-processing procedure and modified part of the detector to deal with the increased energy and the increased heavy-hadron production cross-section. In this contribution we review the performance of the particle identification detectors at LHCb, Rich, Calorimeters, and Muon system, after the LS1

  4. 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. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Massaro, Lawrence M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jensen, Philip J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-30

    A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power reactor sites was conducted. 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: (1) characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory, (2) a description of the on-site infrastructure and conditions relevant to transportation of SNF and GTCC waste, (3) an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing SNF and GTCC waste, including identification of gaps in information, and (4) an evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. Every 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 important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. It is expected that additional site visits will be conducted to add to the information presented in the evaluation.

  5. Shutdown channels and fitted interlocks in atomic reactors

    International Nuclear Information System (INIS)

    Furet, J.; Landauer, C.

    1968-01-01

    This catalogue consists of tables (one per reactor) giving the following information: number and type of detectors, range of the shutdown channels, nature of the associated electronics, thresholds setting off the alarms, fitted interlocks. These cards have been drawn up with a view to an examination of the reactors safety by the 'Reactor Safety Sub-Commission', they take into account the latest decisions. The reactors involved in this review are: Azur, Cabri, Castor-Pollux, Cesar-Marius-2, Edf-2, EL3, EL4, Eole, G1, G2-G3, Harmonie, Isis, Masurca, Melusine, Minerve, Osiris, Pegase, Peggy, PAT, Rapsodie, SENA, Siloe, Siloette, Triton-Nereide, and Ulysse. (authors) [fr

  6. 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

  7. The String Shutdown Report December 97 - March 98

    CERN Document Server

    Casas-Cubillos, J; Favre, G; Herzog, R; Jacquemod, A; Missiaen, D; Saban, R; Struik, M

    1998-01-01

    The main reason for the shutdown was the installation of a tube containing a prototype auxiliary bus-bars cable. This tube runs in one of the beam tube apertures of the String from the front of MB1 to the rear of MB3 and is hydraulically connected to the cold mass of MB3. A ceramic leak tight feed-through was installed, for the first time in operational conditions, to route the signal wires for the temperature sensors and the voltage taps out of the 1.9 K helium bath. Leaks in the beam-screen capillary had prevented the connection of the beam screens to the cooling circuit. The opportunity of t his shutdown was taken to install a cryogenically cooled beam-screen in the other aperture of MB3. In addition, the calibration of temperature and positioning sensors took place. The SRB had to be re moved to install the long tube and the lines carrying cryogens had to be cut, therefore a pressure test and a leak test had to be carried-out.

  8. Evolution of the ATLAS Distributed Computing during the LHC long shutdown

    CERN Document Server

    Campana, S; The ATLAS collaboration

    2013-01-01

    The ATLAS Distributed Computing project (ADC) was established in 2007 to develop and operate a framework, following the ATLAS computing model, to enable data storage, processing and bookkeeping on top of the WLCG distributed infrastructure. ADC development has always been driven by operations and this contributed to its success. The system has fulfilled the demanding requirements of ATLAS, daily consolidating worldwide up to 1PB of data and running more than 1.5 million payloads distributed globally, supporting almost one thousand concurrent distributed analysis users. Comprehensive automation and monitoring minimized the operational manpower required. The flexibility of the system to adjust to operational needs has been important to the success of the ATLAS physics program. The LHC shutdown in 2013-2015 affords an opportunity to improve the system in light of operational experience and scale it to cope with the demanding requirements of 2015 and beyond, most notably a much higher trigger rate and event pileu...

  9. Performance of Resistive Plate Chambers installed during the first long shutdown of the CMS experiment

    CERN Document Server

    Shopova, M.; Aleksandrov, A.; Hadjiiska, R.; Iaydjiev, P.; Sultanov, G.; Rodozov, M.; Stoykova, S.; Assran, Y.; Sayed, A.; Radi, A.; Aly, S.; Singh, G.; Abbrescia, M.; Iaselli, G.; Maggi, M.; Pugliese, G.; Verwilligen, P.; Van Doninck, W.; Colafranceschi, S.; Sharma, A.; Benussi, L.; Bianco, S.; Piccolo, D.; Primavera, F.; Cimmino, A.; Crucy, S.; Rios, A.A.O.; Tytgat, M.; Zaganidis, N.; Gul, M.; Fagot, A.; Bhatnagar, V.; Singh, J.; Kumari, R.; Mehta, A.; Ahmad, A.; Awan, I.M.; Shahzad, H.; Hoorani, H.; Asghar, M.I.; Muhammad, S.; Ahmed, W.; Shah, M.A.; Cho, S.W.; Choi, S.Y.; Hong, B.; Kang, M.H.; Lee, K.S.; Lim, J.H.; Park, S.K.; Kim, M.S.; Laktineh, I.B.; Lagarde, F.; Gouzevitch, M.; Grenier, G.; Pedraza, I.; Bernardino, S. Carpinteyro; Estrada, C. Uribe; Carrillo Moreno, S.; Valencia, F. Vazquez; Pant, L.M.; Buontempo, S.; Cavallo, N.; Fabozzi, F.; Orso, I.; Lista, L.; Meola, S.; Merola, M.; Paolucci, P.; Thyssen, F.; Lanza, G.; Esposito, M.; Braghieri, A.; Magnani, A.; Riccardi, C.; Salvini, P.; Vai, I.; Vitulo, P.; Montagna, P.; Ban, Y.; Qian, S.J.; Choi, M.; Choi, Y.; Goh, J.; Kim, D.; Dimitrov, A.; Litov, L.; Petkov, P.; Pavlov, B.; Bagaturia, I.; Lomidze, D.; Avila, C.; Cabrera, A.; Sanabria, J.C.; Crotty, I.; Vaitkus, J.

    2016-01-01

    The CMS experiment, located at the CERN Large Hadron Collider, has a redundant muon system composed by three different detector technologies: Cathode Strip Chambers (in the forward regions), Drift Tubes (in the central region) and Resistive Plate Chambers (both its central and forward regions). All three are used for muon reconstruction and triggering. During the first long shutdown (LS1) of the LHC (2013-2014) the CMS muon system has been upgraded with 144 newly installed RPCs on the forth forward stations. The new chambers ensure and enhance the muon trigger efficiency in the high luminosity conditions of the LHC Run2. The chambers have been successfully installed and commissioned. The system has been run successfully and experimental data has been collected and analyzed. The performance results of the newly installed RPCs will be presented.

  10. Accident Tolerant Reactor Shutdown for NTP Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In brief, USNC's accident submersion safe drums are control drums where a small amount of fuel is added opposite to the neutron absorber and the drums impinge on the...

  11. Identification of Human-induced Initiating Event in the Low and Shutdown operation by using CESA method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Chan; Kim, Jong Hyun [KEPCO International nuclear Graduate School, Ulsan (Korea, Republic of)

    2014-08-15

    This paper suggests a procedure to identify human-induced initiating events during low and shutdown state in Nuclear Power Plant (NPP). Human-induced initiating events, also called Category B actions in human reliability analysis (HRA), are operator actions that may lead directly to initiating events either by themselves or in combination with equipment failures. Most of conventional probabilistic safety analyses (PSAs) typically assume that the frequency of initiating events also includes the probability of human-induced initiating events. However, some regulatory documents require Category B actions to be specifically analyzed and quantified in the PSA. In addition, a NUREG report also addresses that an explicit modeling of Category B actions could potentially lead to important insights for human performance on safety. However, there is no standard procedure to identify Category B actions which are either recommended by regulations or widely used in the PSA. This paper develops a systematic procedure to identify the Category B actions for the shutdown and low power. The procedure includes several steps to derive operator actions that may lead to initiating events in the low and shutdown stage. Those steps are the selection of initiating events to be analyzed, the selection of systems or components, the screening of unlikely operating actions, and quantification of initiating events. The procedure also suggests the detailed activity of each step such as the information required, screening rules, and output of steps. Finally, the applicability of the suggested approach is also investigated to show its feasibility.

  12. Two examples of digital computing devices used in equipments important to safety: the CONTROBLOC and emergency shutdown of the reactor SUPERPHENIX

    International Nuclear Information System (INIS)

    Bouchez, H.; Gendrin, M.; Percin de

    1986-01-01

    The paper describes the use of digital computing devices for periodically checking for failures in the equipments important to safety. Two examples of such approaches are presented: the safety programmable automation CONTROBLOCK and the emergency shutdown system by which rods fall for SUPERPHENIX reactor

  13. CORAL and COOL during the LHC long shutdown

    CERN Multimedia

    Valassi, A; Dykstra, D; Goyal, N; Salnikov, A; Trentadue, R; Wache, M

    2013-01-01

    CORAL and COOL are two software packages used by the LHC experiments for managing detector conditions and other types of data using relational database technologies. They have been developed and maintained within the LCG Persistency Framework, a common project of the CERN IT department with ATLAS, CMS and LHCb. This presentation reports on the status of CORAL and COOL at the time of CHEP2013, covering the new features and enhancements in both packages, as well as the changes and improvements in the software process infrastructure. It also reviews the usage of the software in the experiments and the outlook for ongoing and future activities during the LHC long shutdown (LS1) and beyond.

  14. High level waste facilities - Continuing operation or orderly shutdown

    International Nuclear Information System (INIS)

    Decker, L.A.

    1998-04-01

    Two options for Environmental Impact Statement No action alternatives describe operation of the radioactive liquid waste facilities at the Idaho Chemical Processing Plant at the Idaho National Engineering and Environmental Laboratory. The first alternative describes continued operation of all facilities as planned and budgeted through 2020. Institutional control for 100 years would follow shutdown of operational facilities. Alternatively, the facilities would be shut down in an orderly fashion without completing planned activities. The facilities and associated operations are described. Remaining sodium bearing liquid waste will be converted to solid calcine in the New Waste Calcining Facility (NWCF) or will be left in the waste tanks. The calcine solids will be stored in the existing Calcine Solids Storage Facilities (CSSF). Regulatory and cost impacts are discussed

  15. 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...

  16. 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...

  17. 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 ...

  18. 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...

  19. 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...

  20. 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...

  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. Transient Analysis of Station Blackout While Shutdown for OPR1000 Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Su Hyun; Kim, Min Hwa [FNC Technology Co., Yongin (Korea, Republic of); Yoon, Duk Joo; Lee, Seung Chan [KHNP, Daejeon (Korea, Republic of)

    2016-10-15

    Some studies have been performed to support and provide useful insights for operator guidelines to maintain critical safety functions during a Station Blackout (SBO) or ELAP event for shutdown modes. Shutdown SBO Guideline has been issued to provide instructions for responding to a SBO, including an ELAP, while shutdown with SIAS (Safety Injection Actuation Signal) blocked and fuel in the reactor vessel. The thermal-hydraulic transient analysis using RELAP5/Mod3.3 code was performed to provide insights for shutdown SBO for OPR1000 NPP. It will be helpful for developing a strategy to cope with shutdown SBO for OPR1000 NPP. The thermal-hydraulic transient analysis was performed to provide insights for shutdown SBO. For Shutdown State A, if SG ADV is opened by operator manual action within 4,000 sec, then 6 hour is available to avoid core uncovery and damage. 6 hour is sufficient time for operator to prepare the secondary external injection. For Shutdown State C, if RWST gravity feed is provided by operator manual action within 4,000 sec, then 24 hour is available to avoid core uncovery and damage. 24 hour is sufficient time for operator to prepare the primary external injection or refill RWST. This calculation results can be directly applied to the development of Plant Specific Technical Guide (PSTG) for OPR1000 NPP.

  3. 76 FR 81998 - Methodology for Low Power/Shutdown Fire PRA

    Science.gov (United States)

    2011-12-29

    ... COMMISSION Methodology for Low Power/Shutdown Fire PRA AGENCY: Nuclear Regulatory Commission. ACTION: Draft... public comment a draft NUREG/CR, NUREG/CR-7114, Revision 0, ``Methodology for Low Power/Shutdown Fire PRA...-2011-0295. Discussion The draft NUREG presents a probabilistic risk assessment (PRA) method for...

  4. 77 FR 10576 - Methodology for Low Power/Shutdown Fire PRA

    Science.gov (United States)

    2012-02-22

    ... COMMISSION Methodology for Low Power/Shutdown Fire PRA AGENCY: Nuclear Regulatory Commission. ACTION: Draft... Draft NUREG/CR-7114, Revision 0, ``Methodology for Low Power/Shutdown Fire PRA.'' In response to request...-2011-0295. Discussion The draft NUREG presents a probabilistic risk assessment (PRA) method for...

  5. Variation of Loads on Offshore Wind Turbine Drivetrains During Measured Shutdown Events

    DEFF Research Database (Denmark)

    Natarajan, Anand

    2016-01-01

    -megawatt wind turbine located at an offshore wind farm are correlated with corresponding observations of shutdowns on surrounding wind turbines. The observed wind turbines have multiple shutdowns at high mean wind speeds due to wind speed variations near cut-out. Through the use of an Inverse First Order...

  6. Shielding optimisation of the ITER ICH&CD antenna for shutdown dose rate

    International Nuclear Information System (INIS)

    Turner, Andrew; Leichtle, Dieter; Lamalle, Philippe; Levesy, Bruno; Meunier, Lionel; Polunovskiy, Eduard; Sartori, Roberta; Shannon, Mark

    2015-01-01

    Highlights: • Neutronics analysis on the ITER ICH&CD system conducted to reduce shutdown dose rate. • Several designs for shielding the port plug gaps were modelled. • Shielding significantly reduced interspace dose rate but still exceed project requirements. • Design optimisation of the ICH port is continuing. • Significant contributions from other ports require an integrated modelling approach. - Abstract: The Ion Cyclotron Heating and Current Drive (ICH&CD) system will reside in ITER equatorial port plugs 13 and 15. Shutdown dose rates (SDDR) within the port interspace are required to be less than 100 μSv/h at 10 6 s cooling. A significant contribution to the SDDR results from neutrons streaming down gaps around the port frame, and the mitigation of this streaming is the main subject of these analyses. An updated MCNP model of the antenna was created and integrated into an ITER reference model. Shielding plates were defined in the port gaps, and scoping studies conducted to assess their effectiveness in several configurations, based on which a front dog-leg arrangement was selected for high resolution 3-D activation analysis using MCR2S. It was concluded that the selected configuration reduced the SDDR from ∼500 μSv/h to 220 μSv/h but were still in excess of dose rate requirements. Approximately 30% of this was due to cross-talk from neighbouring ports. In addition, increased dose rates were observed in the port interspace along the lines of sight of the removable vacuum transmission lines. Design optimisation is continuing, however an integrated approach is needed with regard to ITER port plug design and the shielding of surrounding systems.

  7. Shielding optimisation of the ITER ICH&CD antenna for shutdown dose rate

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: andrew.turner@ccfe.ac.uk [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Leichtle, Dieter [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Lamalle, Philippe; Levesy, Bruno [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St., Paul-lez-Durance (France); Meunier, Lionel [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Polunovskiy, Eduard [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St., Paul-lez-Durance (France); Sartori, Roberta [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain); Shannon, Mark [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2015-10-15

    Highlights: • Neutronics analysis on the ITER ICH&CD system conducted to reduce shutdown dose rate. • Several designs for shielding the port plug gaps were modelled. • Shielding significantly reduced interspace dose rate but still exceed project requirements. • Design optimisation of the ICH port is continuing. • Significant contributions from other ports require an integrated modelling approach. - Abstract: The Ion Cyclotron Heating and Current Drive (ICH&CD) system will reside in ITER equatorial port plugs 13 and 15. Shutdown dose rates (SDDR) within the port interspace are required to be less than 100 μSv/h at 10{sup 6} s cooling. A significant contribution to the SDDR results from neutrons streaming down gaps around the port frame, and the mitigation of this streaming is the main subject of these analyses. An updated MCNP model of the antenna was created and integrated into an ITER reference model. Shielding plates were defined in the port gaps, and scoping studies conducted to assess their effectiveness in several configurations, based on which a front dog-leg arrangement was selected for high resolution 3-D activation analysis using MCR2S. It was concluded that the selected configuration reduced the SDDR from ∼500 μSv/h to 220 μSv/h but were still in excess of dose rate requirements. Approximately 30% of this was due to cross-talk from neighbouring ports. In addition, increased dose rates were observed in the port interspace along the lines of sight of the removable vacuum transmission lines. Design optimisation is continuing, however an integrated approach is needed with regard to ITER port plug design and the shielding of surrounding systems.

  8. Aggregation of flexible domestic heat pumps for the provision of reserve in power systems

    OpenAIRE

    Georges, Emeline; Quoilin, Sylvain; Mathieu, Sébastien; Lemort, Vincent

    2017-01-01

    The integration of renewable energy sources in the electricity production mix has an important impact on the management of the electricity grid, due to their intermittency. In particular, there is a rising need for flexibility, both on the supply and demand sides. This paper assesses the amount of flexibility that could be reserved from a set of flexible residential heat pumps in a given geographical area. It addresses the problem of a load aggregator controlling a set of heat pumps used to p...

  9. Increasing efficiency of TPP fuel suply system due to LNG usage as a reserve fuel

    Science.gov (United States)

    Zhigulina, E. V.; Khromchenkov, V. G.; Mischner, J.; Yavorovsky, Y. V.

    2017-11-01

    The paper is devoted to the analysis of fuel economy efficiency increase possibility at thermal power plants (TPP) due to the transition from the use of black oil as a reserve fuel to liquefied natural gas (LNG) produced at the very station. The work represents the technical solution that allows to generate, to store and to use LNG as the reserve fuel TPP. The annual amounts of black oil and natural gas that are needed to ensure the reliable operation of several power plants in Russia were assessed. Some original schemes of the liquefied natural gas production and storing as alternative reserve fuel generated by means of application of expansion turbines are proposed. The simulation results of the expansion process for two compositions of natural gas with different contents of high-boiling fractions are presented. The dependences of the condensation outlet and power generation from the flow initial parameters and from the natural gas composition are obtained and analysed. It was shown that the choice of a particular circuit design depends primarily on the specific natural gas composition. The calculations have proved the effectiveness and the technical ability to use liquefied natural gas as a backup fuel at reconstructed and newly designed gas power station.

  10. Water quality, meteorological, and nutrient data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP), 1994 - 2005 (NODC Accession 0019215)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality, meteorological, and nutrient data in 25...

  11. Replacement energy, capacity, and reliability costs for permanent nuclear reactor shutdowns

    International Nuclear Information System (INIS)

    VanKuiken, J.C., Buehring, W.A.; Hamilton, S.; Kavicky, J.A.; Cavallo, J.D.; Veselka, T.D.; Willing, D.L.

    1993-10-01

    Average replacement power costs are estimated for potential permanent shutdowns of nuclear electricity-generating units. Replacement power costs are considered to include replacement energy, capacity, and reliability cost components. These estimates were developed to assist the US Nuclear Regulatory Commission in evaluating regulatory issues that potentially affect changes in serious reactor accident frequencies. Cost estimates were derived from long-term production-cost and capacity expansion simulations of pooled utility-system operations. Factors that affect replacement power cost, such as load growth, replacement sources of generation, and capital costs for replacement capacity, were treated in the analysis. Costs are presented for a representative reactor and for selected subcategories of reactors, based on estimates for 112 individual reactors

  12. 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 ...

  13. Endothelial and non-endothelial coronary blood flow reserve and left ventricular dysfunction in systemic hypertension

    Directory of Open Access Journals (Sweden)

    Aloísio Marchi Rocha

    2009-04-01

    Full Text Available OBJECTIVES: We evaluated the impairment of endothelium-dependent and endothelium-independent coronary blood flow reserve after administration of intracoronary acetylcholine and adenosine, and its association with hypertensive cardiac disease. INTRODUCTION: Coronary blood flow reserve reduction has been proposed as a mechanism for the progression of compensated left ventricular hypertrophy to ventricular dysfunction. METHODS: Eighteen hypertensive patients with normal epicardial coronary arteries on angiography were divided into two groups according to left ventricular fractional shortening (FS. Group 1 (FS >0.25: n=8, FS=0.29 ± 0.03; Group 2 (FS <0.25: n=10, FS= 0.17 ± 0.03. RESULTS: Baseline coronary blood flow was similar in both groups (Group 1: 80.15 ± 26.41 mL/min, Group 2: 100.09 ± 21.51 mL/min, p=NS. In response to adenosine, coronary blood flow increased to 265.1 ± 100.2 mL/min in Group 1 and to 300.8 ± 113.6 mL/min (p <0.05 in Group 2. Endothelium-independent coronary blood flow reserve was similar in both groups (Group 1: 3.31 ± 0.68 and Group 2: 2.97 ± 0.80, p=NS. In response to acetylcholine, coronary blood flow increased to 156.08 ± 36.79 mL/min in Group 1 and to 177.8 ± 83.6 mL/min in Group 2 (p <0.05. Endothelium-dependent coronary blood flow reserve was similar in the two groups (Group 1: 2.08 ± 0.74 and group Group 2: 1.76 ± 0.61, p=NS. Peak acetylcholine/peak adenosine coronary blood flow response (Group 1: 0.65 ± 0.27 and Group 2: 0.60 ± 0.17 and minimal coronary vascular resistance (Group 1: 0.48 ± 0.21 mmHg/mL/min and Group 2: 0.34 ± 0.12 mmHg/mL/min were similar in both groups (p= NS. Casual diastolic blood pressure and end-systolic left ventricular stress were independently associated with FS. CONCLUSIONS: In our hypertensive patients, endothelium-dependent and endothelium-independent coronary blood flow reserve vasodilator administrations had similar effects in patients with either normal or decreased left

  14. 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.

  15. Shutdown dose rate analysis with CAD geometry, Cartesian/tetrahedral mesh, and advanced variance reduction

    International Nuclear Information System (INIS)

    Biondo, Elliott D.; Davis, Andrew; Wilson, Paul P.H.

    2016-01-01

    Highlights: • A CAD-based shutdown dose rate analysis workflow has been implemented. • Cartesian and superimposed tetrahedral mesh are fully supported. • Biased and unbiased photon source sampling options are available. • Hybrid Monte Carlo/deterministic techniques accelerate photon transport. • The workflow has been validated with the FNG-ITER benchmark problem. - Abstract: In fusion energy systems (FES) high-energy neutrons born from burning plasma activate system components to form radionuclides. The biological dose rate that results from photons emitted by these radionuclides after shutdown—the shutdown dose rate (SDR)—must be quantified for maintenance planning. This can be done using the Rigorous Two-Step (R2S) method, which involves separate neutron and photon transport calculations, coupled by a nuclear inventory analysis code. The geometric complexity and highly attenuating configuration of FES motivates the use of CAD geometry and advanced variance reduction for this analysis. An R2S workflow has been created with the new capability of performing SDR analysis directly from CAD geometry with Cartesian or tetrahedral meshes and with biased photon source sampling, enabling the use of the Consistent Adjoint Driven Importance Sampling (CADIS) variance reduction technique. This workflow has been validated with the Frascati Neutron Generator (FNG)-ITER SDR benchmark using both Cartesian and tetrahedral meshes and both unbiased and biased photon source sampling. All results are within 20.4% of experimental values, which constitutes satisfactory agreement. Photon transport using CADIS is demonstrated to yield speedups as high as 8.5·10 5 for problems using the FNG geometry.

  16. Shutdown dose rate contribution from diagnostics in ITER upper port 18

    Energy Technology Data Exchange (ETDEWEB)

    Cheon, M.S., E-mail: munseong@nfri.re.kr [National Fusion Research Institute, Daejeon (Korea, Republic of); Pak, S.; An, Y.H.; Seon, C.R.; Lee, H.G. [National Fusion Research Institute, Daejeon (Korea, Republic of); Bertalot, L.; Krasilnikov, V. [ITER Organization, St Paul-lez-Durance (France); Zvonkov, A. [Agency ITER-RF, Moscow (Russian Federation)

    2016-11-01

    Highlights: • The Shutdown Dose Rate in the interspace of ITER upper port 18 was evaluated. • VUV spectrometer is the dominant contributor to the average SDR. • The existence and size of the blanket cooling pipes impacts significantly on SDR. - Abstract: D-T operation of ITER plasma will produce high-energy fusion neutrons those can activate materials around the place where human-access is necessary. The interspace of the diagnostic port is one of the area where human-access is necessary for the maintenance of diagnostic systems installed at the port, so it is important to evaluate a dose rate of the interspace area in order to comply with ALARA principle. The shutdown dose rate (SDR) in the interspace of ITER upper port 18 was evaluated by the Direct 1-Step (D1S) method using MCNP5 code. This port contains three diagnostics: Vacuum Ultra-Violet (VUV) Spectrometer, Neutron Activation System (NAS), and Upper Vertical Neutron Camera (UVNC). The contribution of each diagnostic in the port was evaluated by running separate upper port MCNP models those contain individual diagnostic only, and the total dose rate contribution was evaluated with the model which was fully integrated with all the diagnostics. The effect of the opening around the upper port plug and of the other ports was also investigated. The purpose of this assessment is to provide the shielding design basis for the preliminary design of the diagnostic integration in the port. The method and result of the calculation will be presented in this paper.

  17. Shutdown dose rate analysis with CAD geometry, Cartesian/tetrahedral mesh, and advanced variance reduction

    Energy Technology Data Exchange (ETDEWEB)

    Biondo, Elliott D., E-mail: biondo@wisc.edu; Davis, Andrew, E-mail: davisa@engr.wisc.edu; Wilson, Paul P.H., E-mail: wilsonp@engr.wisc.edu

    2016-05-15

    Highlights: • A CAD-based shutdown dose rate analysis workflow has been implemented. • Cartesian and superimposed tetrahedral mesh are fully supported. • Biased and unbiased photon source sampling options are available. • Hybrid Monte Carlo/deterministic techniques accelerate photon transport. • The workflow has been validated with the FNG-ITER benchmark problem. - Abstract: In fusion energy systems (FES) high-energy neutrons born from burning plasma activate system components to form radionuclides. The biological dose rate that results from photons emitted by these radionuclides after shutdown—the shutdown dose rate (SDR)—must be quantified for maintenance planning. This can be done using the Rigorous Two-Step (R2S) method, which involves separate neutron and photon transport calculations, coupled by a nuclear inventory analysis code. The geometric complexity and highly attenuating configuration of FES motivates the use of CAD geometry and advanced variance reduction for this analysis. An R2S workflow has been created with the new capability of performing SDR analysis directly from CAD geometry with Cartesian or tetrahedral meshes and with biased photon source sampling, enabling the use of the Consistent Adjoint Driven Importance Sampling (CADIS) variance reduction technique. This workflow has been validated with the Frascati Neutron Generator (FNG)-ITER SDR benchmark using both Cartesian and tetrahedral meshes and both unbiased and biased photon source sampling. All results are within 20.4% of experimental values, which constitutes satisfactory agreement. Photon transport using CADIS is demonstrated to yield speedups as high as 8.5·10{sup 5} for problems using the FNG geometry.

  18. An investigation of scramming the outer shutdown rods of the ANS with no reversal of flow in the manifold inlet lines

    International Nuclear Information System (INIS)

    Morsk, K.

    1992-10-01

    This report provides calculations and calculation checks on the outer shutdown system, consisting of eight shutdown rods located on the outside of the core. The function of the system is to scram the reactor, or to break the chain reaction of the fission process. The shutdown rods are clad with a neutron-absorbing material (i.e., hafnium) to achieve scram. During normal operation, the outer shutdown rods (Fig. 1) are in a nonscram, withdrawn position. This means that they are not close enough to the core to absorb a significant number of the neutrons that cause the fission process. In the case of a malfunction or an emergency, the outer control rods are moved to a position near the core. The outer shutdown system is operated with the use of springs and hydraulics. During normal operation, a constant flow of heavy water is circulated through the reflector vessel. A part of this flow provides a pressure high enough to keep the rods in their withdrawn or upper position, a nonscram status. If any signs of abnormal operation occur, the valves in the hydraulic system cut off the flow, and the springs push the rods into the scram position, stopping the chain reaction. Once the flow is restarted, the rods can be withdrawn to the nonscram position. Calculations of the mass of the outer control rod, the scram spring data, and the hydraulic pressure to hold the rods in the withdrawn position have been checked. In the case of a malfunction of the flow/pressure relief valves, a calculation was needed to show that the scram time would not exceed the time allowed. The scram time has been determined based on different values of the rod insertion length and the outside radius of the annulus was calculated. The effective force pushing the rod into the scram position, the rate of acceleration, and the actual scram time was then determined

  19. Combined assessment of attentional reserve and cognitive-motor effort under various levels of challenge with a dry EEG system.

    Science.gov (United States)

    Gentili, Rodolphe J; Jaquess, Kyle J; Shuggi, Isabelle M; Shaw, Emma P; Oh, Hyuk; Lo, Li-Chuan; Tan, Ying Ying; Domingues, Clayton A; Blanco, Justin A; Rietschel, Jeremy C; Miller, Matthew W; Hatfield, Bradley D

    2018-02-09

    A novel ERP approach was proposed to index variations in mental workload, particularly in attentional reserve, which is complementary to EEG spectral content thought to reflect mental effort. To our knowledge, no study has assessed mental effort and attentional reserve simultaneously in EEG gel-based and, importantly, dry systems, which are particularly well suited for real-world settings. Therefore, by systematically considering ERP, EEG spectral, and importantly the combination of both, this study examined if a small set of dry EEG electrodes could detect changes in both spectral and ERP metrics to assess the mental workload under various challenges with a similar fidelity to their gel-based counterparts in a laboratory setting. By employing both EEG gel-based and dry systems, the ERP and spectral markers were computed while participants executed a visuomotor task under three levels of challenge. For both EEG systems, more challenging levels of difficulty were associated with concomitant changes in ERP amplitude, and spectral power reflected a reduction of the attentional reserve and an increase in cognitive-motor effort, respectively. Those variations in attentional reserve and cognitive-motor effort collectively indexed mental workload with nearly identical fidelity for both gel-based and dry EEG systems. These findings promise to assess the mental workload in situations where the use of dry EEG systems could be advantageously employed to examine human cognitive-motor performance. © 2018 Society for Psychophysiological Research.

  20. Sizing of an Energy Storage System for Grid Inertial Response and Primary Frequency Reserve

    DEFF Research Database (Denmark)

    Knap, Vaclav; Chaudhary, Sanjay Kumar; Stroe, Daniel Loan

    2016-01-01

    event in the power system with a high penetration of wind power. An energy storage system (ESS) might be a viable solution for providing inertial response and primary frequency regulation. A methodology has been presented here for the sizing of the ESS in terms of required power and energy. It describes......Large-scale integration of renewable energy sources in power system leads to the replacement of conventional power plants (CPPs) and consequently challenges in power system reliability and security are introduced. This study is focused on improving the grid frequency response after a contingency...... the contribution of the ESS to the grid, in terms of inertial constant and droop. The methodology is applied to a 12-bus grid model with high wind power penetration. The estimated ESS size for inertial response and primary frequency regulation services are validated through real-time simulations. Moreover...

  1. Study of double phases corium atmosphere fission product time. Evolution after a nuclear reactor emergency shutdown by using Phado code

    International Nuclear Information System (INIS)

    Tsilanizara, A.; Diop, C.M.; Nimal, J.C.; Nimal, B.; Maro, D.

    1994-01-01

    This paper deals with the PHADO code which is a part of the ESCADRE (French system of accident analysis codes for Water Reactors). The objectives of ESCADRE system is to characterize (quantitatively, qualitatively) for all the accident duration, the fission products behaviour and to define and evaluate the means for severe accident mitigation and management (limitation of core degradation and containment failure). The PHADO code treats the fission products aspects in the corium and in the atmosphere: mass, concentration, activity, residual gamma and beta decay heating for any cooling time after the emergency shutdown. (TEC)

  2. 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...

  3. 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...

  4. 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...

  5. Best estimate analysis of the thermal expansion scenario during shutdown in a PWR

    International Nuclear Information System (INIS)

    Macian, R.; Nechvatal, L.

    2001-01-01

    In this paper we examine the consequences following the hypothetical failure of the Residual Heat Removal (RHR) system during the shutdown operating mode in a Pressurized Water Reactor (PWR). If the RHR system decay heat removal capability cannot be ensured, then the decay heat released in the core will heat up the Reactor Coolant System (RCS) inventory and will cause it to expand. If the thermal expansion is such that the entire RCS becomes ''water-solid'', that is, completely filled with water, then further expansion will result in a rapid increase of the RCS pressure. Such a situation could threaten the integrity of the RCS pressure boundary and lead to a dangerous break in the primary system or in the lines of the systems connected to it, e.g. RHR system. The pressure increase can be arrested by the opening of the pressurizer relief valves (PORVs) or, in those PWRs in which the RHR system is not isolated after it fails, by the opening of the pressure relief valve in the RHR system line. The purpose of the analyses presented in this paper is to determine whether mitigating measures, such as the opening of only one of the PORV and the RHR relief valve, are capable of preventing a fast pressure increase. (author)

  6. Analysis of Multiserver Queueing System with Opportunistic Occupation and Reservation of Servers

    Directory of Open Access Journals (Sweden)

    Bin Sun

    2014-01-01

    Full Text Available We consider a multiserver queueing system with two input flows. Type-1 customers have preemptive priority and are lost during arrival only if all servers are occupied by type-1 customers. If all servers are occupied, but some provide service to type-2 customers, service of type-2 customer is terminated and type-1 customer occupies the server. If the number of busy servers is less than the threshold M during type-2 customer arrival epoch, this customer is accepted. Otherwise, it is lost or becomes a retrial customer. It will retry to obtain service. Type-2 customer whose service is terminated is lost or moves to the pool of retrial customers. The service time is exponentially distributed with the rate dependent on the customer’s type. Such queueing system is suitable for modeling cognitive radio. Type-1 customers are interpreted as requests generated by primary users. Type-2 customers are generated by secondary or cognitive users. The problem of optimal choice of the threshold M is the subject of this paper. Behavior of the system is described by the multidimensional Markov chain. Its generator, ergodicity condition, and stationary distribution are given. The system performance measures are obtained. The numerical results show the effectiveness of considered admission control.

  7. Using Guided Local Search for Adaptive Resource Reservation in Large-scale Embedded Systems

    NARCIS (Netherlands)

    ter Braak, T.D.

    2014-01-01

    To maintain a predictable execution environment, an embedded system must ensure that applications are, in advance, provided with sufficient resources to process tasks, exchange information and to control peripherals. The problem of assigning tasks to processing elements with limited resources, and

  8. Adjustment of the Kompleks Titan-2 monitoring computerized system at the Rovno NPP third unit

    International Nuclear Information System (INIS)

    Zigaev, B.P.

    1987-01-01

    Information signal origin and processing processes in the monitoring computerized system 'Komplex Titan-2' at the Rovno NPP third unit are considered. The system exercises control over the following production equipment parameters: the state of keys of control of lock fittings, mechanisms, regulators, reserve mechanism automatic shut-down circuit; the state of lock fittings, mechanisms, regulators, reserve mechanism automated switching on; parameter deviation from permissible values; interlock operation; protection system state; the state of autonomous units and devices

  9. 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

  10. Quality of the current low power and shutdown PSA practice

    International Nuclear Information System (INIS)

    Jang, Seung Cheol; Park, Jin Hee; Lim, Ho Gon; Kim, Tae Woon

    2004-01-01

    A probabilistic safety assessment (PSA) for the low-power and shutdown (LPSD) modes in a Korea standard nuclear power plant (KSNP) has been performed for the purpose of estimating the LPSD risk and identifying the vulnerabilities of LPSD operations. Both the operational experience and PSA results indicate that the risks from LPSD operations could be comparable with those from power operations. However, the application of the LPSD risk insights to risk-informed decision making has been slow to be adopted in practice. It is largely due to the question of whether the current LPSD PSA practice is appropriate for application to risk-informed decision making or not. Such a question has to do with the quality of the current LPSD PSA practice. In this paper, we have performed self-assessment of the KSNP LPSD PSA quality based on the ANS Standard (draft as of 13 Sep. 2002). The aims of the work are to find the LPSD PSA technical areas insufficient for application to risk-informed decision making and to efficiently allocate the limited research resources to improve the LPSD PSA model quality. Many useful findings regarding the current LPSD PSA quality are presented in this paper

  11. Energy of the LHC after the 2013-2014 shutdown

    International Nuclear Information System (INIS)

    Todesco, E.; Lorin, C.; Bajko, M.

    2012-01-01

    In 2008 all the LHC main dipole circuits were trained to 5 TeV, two sectors to 6 TeV, and one sector was pushed up to 6.6 TeV. In the 5-6 TeV range, a few quenches were needed to retrain the LHC dipoles, and none for the quadrupoles. On the other hand, in the 6- 7 TeV range a larger than expected number of quenches was observed in the main dipoles. Using this limited set of data, tentative estimates were given to guess the number of quenches needed to reach nominal energy. After three years, the only additional experimental data are the retraining of the magnets individually tested at SM18, either coming from the spares or from the 3-4 sector. After presenting this additional information, we will consider the different scenarios that can be envisaged to train the LHC main magnets after the Long Shut-down 1 (LS1), the expected energy, the impact on the commissioning time and the associated risk. (authors)

  12. HEART RATE VARIABILITY AS THE ADAPTATION RESERVE INDICATOR OF CARDIOVASCULAR SYSTEM

    Directory of Open Access Journals (Sweden)

    Aksana Kotava

    2014-12-01

    Full Text Available Background: The efectiveness of the vegetative regulation action might be controlled by the method of heart rate variability (HRV, which has been very popularly used over the last 10 years worldwide. The analysis of many clinical studies indicates that the severity of the disease might be controlled using the method of HRV. Material and methods: All the experimental and controlled group participants, which consisted of healthy students with none sports experience, underwent the examination according to the 5-minute standard protocol of HRV. In addition, all the examinees performed a bicycle stress test. After the bicycle stress test, some additional tests of HRV were also carried out. Results: It was found that some signifcant diferences, between the group of sportsmen and the group of patients, exist. The parasympathetic activity of LF is maximum in athletes and tends to decrease in patients with cardiovascular pathologies. The decreases of the activity of the vasomotor centre was noticed in both study groups. The sympathetic system activity was the lowest in athletes. Conclusions: At the high depression of the vegetative regulation, any signifcant load (physical or psycho-emotional indicates cardiovascular instability which remains beyond the capacity of adaptation. The higher the variability, the more stable the CVS is to the external loads. A sharp decrease of the variability, such as the heart vegetative innervations, causes deteriorating quality of the regulatory mechanisms and, as a result, the risk of cardiovascular diseases increases. Keywords: heart rate variability, deterministic and stochastic loads, cardiovascular system

  13. Thermal-hydraulic calculations using MARS code applied to low power and shutdown probabilistic safety assessment in a PWR

    International Nuclear Information System (INIS)

    Son, Young-Seok; Shin, Jee-Young; Lim, Ho-Gon; Park, Jin-Hee; Jang, Seung-Cheol

    2005-01-01

    The methods developed for full-power probabilistic safety assessment, including thermal-hydraulic methods, have been widely applied to low power and shutdown conditions. Experience from current low power and shutdown probabilistic safety assessments, however, indicates that the thermal-hydraulic methods developed for full-power probabilistic safety assessments are not always reliable when applied to low power and shutdown conditions and consequently may yield misleading and inaccurate risk insights. To increase the usefulness of the low power and shutdown risk insights, the current methods and tools used for thermal-hydraulic calculations should be examined to ascertain whether they function effectively for low power and shutdown conditions. In this study, a platform for relatively detailed thermal-hydraulic calculations applied to low power and shutdown conditions in a pressurized water reactor was developed based on the best estimate thermal-hydraulic analysis code, MARS2.1. To confirm the applicability of the MARS platform to low power and shutdown conditions, many thermal-hydraulic analyses were performed for the selected topic, i.e. the loss of shutdown cooling events for various plant operating states at the Korean standard nuclear power plant. The platform developed in this study can deal effectively with low power and shutdown conditions, as well as assist the accident sequence analysis in low power and shutdown probabilistic safety assessments by providing fundamental data. Consequently, the resulting analyses may yield more realistic and accurate low power and shutdown risk insights

  14. 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

  15. Despite the Shutdown, Rescheduled NIH Research Festival Brings Science to the Forefront | Poster

    Science.gov (United States)

    By Andrea Frydl, Contributing Writer Although it was delayed by almost a month because of the federal shutdown, the NIH Research Festival still took place at the NIH Clinical Center in Bethesda, Md., and attendance was high.

  16. Environmental consequences of a power plant shut-down: a three-dimensional water quality model of Dublin Bay.

    Science.gov (United States)

    Bedri, Zeinab; Bruen, Michael; Dowley, Aodh; Masterson, Bartholomew

    2013-06-15

    A hydro-environmental model is used to investigate the effect of cessation of thermal discharges from a power plant on the bathing water quality of Dublin Bay. Before closing down, cooling water from the plant was mixed with sewage effluent prior to its discharge, creating a warmer, less-saline buoyant pollutant plume that adversely affects the water quality of Dublin Bay. The model, calibrated to data from the period prior to the power-plant shut-down (Scenario1), assessed the water quality following its shut-down under two scenarios; (i) Scenario2: continued abstraction of water to dilute sewage effluents before discharge, and (ii) Scnenario3: sewage effluents are discharged directly into the Estuary. Comparison between scenarios was based on distribution of Escherichia coli (E. coli), a main bathing quality indicator. Scenarios1 and 2, showed almost similar E. coli distribution patterns while Scenario3 displayed significantly higher E. coli concentrations due to the increased stratification caused by the lack of prior dilution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Long-Term Reserve Expansion of Power Systems With High Wind Power Penetration Using Universal Generating Function Methods

    DEFF Research Database (Denmark)

    DING, YI; Wang, Peng; Goel, Lalit

    2010-01-01

    from long term planning point of view utilizing universal generating function (UGF) methods. The reliability models of wind farms and conventional generators are represented as the correspondin UGFs and the special operators for these UGFs are defined to evaluate the customer and the system...... reliabilities. The effect of transmission network on customer reliabilities is also considered in the system UGF. The power output models of wind turbine generators in a wind farm considering wind speed correlation and un-correlation are developed, respectively. A reliability-based reserve expansion method...

  18. Risk-based evaluation of Allowed Outage Times (AOTs) considering risk of shutdown

    International Nuclear Information System (INIS)

    Mankamo, T.; Kim, I.S.; Samanta, P.K.

    1992-01-01

    When safety systems fail during power operation, Technical Specifications (TS) usually limit the repair within Allowed Outage Time (AOT). If the repair cannot be completed within the AOT, or no AOT is allowed, the plant is required to be shut down for the repair. However, if the capability to remove decay heat is degraded, shutting down the plant with the need to operate the affected decay-heat removal systems may impose a substantial risk compared to continued power operation over a usual repair time. Thus, defining a proper AOT in such situations can be considered as a risk-comparison between the repair in frill power state with a temporarily increased level of risk, and the altemative of shutting down the plant for the repair in zero power state with a specific associated risk. The methodology of the risk-comparison approach, with a due consideration of the shutdown risk, has been further developed and applied to the AOT considerations of residual heat removal and standby service water systems of a boiling water reactor (BWR) plant. Based on the completed work, several improvements to the TS requirements for the systems studied can be suggested

  19. Current status of experimental breeder reactor-II [EBR-II] shutdown planning

    International Nuclear Information System (INIS)

    McDermott, M. D.; Griffin, C. D.; Michelbacher, J. A.; Earle, O. K.

    2000-01-01

    The Experimental Breeder Reactor--II (EBR-II) at Argonne National Laboratory--West (ANL-W) in Idaho, was shutdown in September, 1994 as mandated by the US Department of Energy. This sodium cooled reactor had been in service since 1964, and was to be placed in an industrially and radiologically safe condition for ultimate decommissioning. The deactivation of a liquid metal reactor presents unique concerns. The first major task associated with the project was the removal of all fueled assemblies. In addition, sodium must be drained from systems and processed for ultimate disposal. Residual quantities of sodium remaining in systems must be deactivated or inerted to preclude future hazards associated with pyrophoricity and generation of potentially explosive hydrogen gas. A Sodium Process Facility was designed and constructed to react the elemental sodium from the EBR-II primary and secondary systems to sodium hydroxide for disposal. This facility has a design capacity to allow the reaction of the complete inventory of sodium at ANL-W in less than two years. Additional quantities of sodium from the Fermi-1 reactor are also being treated at the Sodium Process Facility. The sodium environment and the EBR-II configuration, combined with the radiation and contamination associated with thirty years of reactor operation, posed problems specific to liquid metal reactor deactivation. The methods being developed and implemented at EBR-II can be applied to other similar situations in the US and abroad

  20. Understanding the hydrologic impacts of wastewater treatment plant discharge to shallow groundwater: Before and after plant shutdown

    Science.gov (United States)

    Hubbard, Laura E.; Keefe, Steffanie H.; Kolpin, Dana W.; Barber, Larry B.; Duris, Joseph W.; Hutchinson, Kasey J.; Bradley, Paul M.

    2016-01-01

    Effluent-impacted surface water has the potential to transport not only water, but wastewater-derived contaminants to shallow groundwater systems. To better understand the effects of effluent discharge on in-stream and near-stream hydrologic conditions in wastewater-impacted systems, water-level changes were monitored in hyporheic-zone and shallow-groundwater piezometers in a reach of Fourmile Creek adjacent to and downstream of the Ankeny (Iowa, USA) wastewater treatment plant (WWTP). Water-level changes were monitored from approximately 1.5 months before to 0.5 months after WWTP closure. Diurnal patterns in WWTP discharge were closely mirrored in stream and shallow-groundwater levels immediately upstream and up to 3 km downstream of the outfall, indicating that such discharge was the primary control on water levels before shutdown. The hydrologic response to WWTP shutdown was immediately observed throughout the study reach, verifying the far-reaching hydraulic connectivity and associated contaminant transport risk. The movement of WWTP effluent into alluvial aquifers has implications for potential WWTP-derived contamination of shallow groundwater far removed from the WWTP outfall.

  1. Spent fuel acceptance scenarios devoted to shutdown reactors: A preliminary analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wood, T.W.; Plummer, A.M.; Dippold, D.G.; Short, S.M. (Pacific Northwest Lab., Richland, WA (USA); Battelle Memorial Inst., Columbus, OH (USA). Office of Transportation Systems and Planning; Pacific Northwest Lab., Richland, WA (USA))

    1989-10-01

    Spent fuel acceptance schedules and the allocation of federal acceptance capacity among commercial nuclear power reactors have important operational and cost consequences for reactor operators. Alternative allocation schemes were investigated to some extent in DOE's MRS Systems Study. The current study supplements these analyses for a class of acceptance schemes in which the acceptance capacity of the federal radioactive waste management system is allocated principally to shutdown commercial power reactors, and extends the scope of analysis to include considerations of at-reactor cask loading rates. The operational consequences of these schemes for power reactors, as measured in terms of quantity of spent fuel storage requirement above storage pool capacities and number of years of pool operations after last discharge, are estimated, as are the associated utility costs. This study does not attempt to examine the inter-utility equity considerations involved in departures from the current oldest-fuel-first (OFF) allocation rule as specified in the Standard Contract for Disposal of Spent Nuclear Fuel and/or High-Level Radioactive Waste.'' In the sense that the alternative allocations are more economically efficient than OFF, however, they approximate the allocations that could result from free exchange of acceptance rights among utilities. Such a process would result in the preservation of inter-utility equity. 13 refs., 9 figs., 9 tabs.

  2. Shutdown decay heat removal analysis: Plant case studies and special issues: Summary report

    International Nuclear Information System (INIS)

    Ericson, D.M. Jr.; Cramond, W.R.; Sanders, G.A.; Hatch, S.W.

    1989-04-01

    Shutdown Decay Heat Removal Requirements has been designated as Unresolved Safety Issue (USI) A-45. The overall objectives of the USI A-45 program were to evaluate the safety adequacy of decay heat removal (DHR) systems in existing light water reactor nuclear power plants and to assess the value and impact (benefit-cost) of alternative measures for improving the overall reliability of the DHR function. To provide the technical data required to meet these objectives a program was developed that examined the state of DHR system reliability in a sample of existing plants. This program identified potential vulnerabilities and identified and established the feasibility of potential measures to improve the reliability of the DHR function. A value/impact (V/I) analysis of the more promising of such measures was conducted and documented. This report summarizes those studies. In addition, because of the evolving nature of V/I analyses in support of regulation, a number of supporting studies related to appropriate procedures and measures for the V/I analyses were also conducted. These studies are also summarized herein. This report only summarizes findings of technical studies performed by Sandia National Laboratories as part of the program to resolve this issue. 46 refs., 7 figs., 124 tabs

  3. The impact of salpingectomy and single-dose systemic methotrexate treatments on ovarian reserve in ectopic pregnancy.

    Science.gov (United States)

    Sahin, Cagdas; Taylan, Enes; Akdemir, Ali; Ozgurel, Banu; Taskıran, Dilek; Ergenoglu, Ahmet M

    2016-10-01

    To investigate the effects of salpingectomy and methotrexate treatments on ovarian reserve in ectopic pregnancy. In this prospective study, a total of 131 patients with ectopic pregnancy were divided into 3 groups of methotrexate (MTX) only (Group-1, n: 55), salpingectomy only (Group-2, n: 61), and salpingectomy following MTX (Group-3, n: 15). Pretreatment and post-treatment anti-Müllerian hormone (AMH) levels were evaluated. Significant differences in AMH levels were detected between group 1 and group 2 (2.52±1.28 vs. 1.96±1.66, p=0.043), and group 1 and group 3 (2.52±1.28 vs. 1.77±0.76, p=0.035) at one month postoperative. However, these differences disappeared at the 3rd postoperative month. When AMH levels were compared within the same group, postoperative one month AMH levels were significantly lower than the preoperative AMH levels only in group 3 (p=0.03). However, this difference also disappeared at the 3rd postoperative month. Systemic single-dose methotrexate treatment, unilateral salpingectomy, and salpingectomy following methotrexate administration in ectopic pregnancy were reassuring based on pretreatment and post-treatment AMH levels. Current medical and surgical treatment approaches do not have an obvious negative effect on ovarian reserve. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Shutdown dose rate analysis of European test blanket modules shields in ITER Equatorial Port #16

    Energy Technology Data Exchange (ETDEWEB)

    Juárez, Rafael, E-mail: rjuarez@ind.uned.es [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain); Sauvan, Patrick; Perez, Lucia [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain); Panayotov, Dobromir; Vallory, Joelle; Zmitko, Milan; Poitevin, Yves [Fusion for Energy (F4E), Torres Diagonal Litoral B3, Josep Pla 2, Barcelona 08019 (Spain); Sanz, Javier [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain)

    2016-11-01

    Highlights: • Nuclear analysis for European TBMs and shields, in ITER Equatorial Port #16, has been conducted in support of the ‘Concept Design Review’ from ITER. • The objective of the work is the characterization of the Shutdown Dose Rates at Equatorial Port #16 interspace. • The role played by the TBM and TBM shields, the equatorial port gaps and the vacuum vessel permeation, in terms of neutron flux transmission is assessed. • The role played by the TBM, TBM shields, Port Plug Frame, Pipe Forest and the machine in terms of activation is also investigated. - Abstract: ‘Fusion for Energy’ (F4E) is designing, developing, and implementing the European Helium-Cooled Lead-Lithium (HCLL) and Helium-Cooled Pebble-Bed (HCPB) Test Blanket Systems (TBSs) for ITER (Nuclear Facility INB-174). An essential element of the Conceptual Design Review (CDR) of these TBSs is the demonstration of capability of Test Blanket Modules (TBM) and their shields to fulfil their function and comply with the design requirements. One of the TBM shields highly relevant design aspects is the project target for shutdown dose rates (SDDR) in the interspace. We investigated two functions of the TBMs and TBM shields—the neutron flux attenuation along the shields, and the reduction of the activation of the components contributing to SDDR. It is shown that TBMs and TBM shields reduce significantly the neutron flux in the port plug (PP). In terms of neutron flux attenuation, the TBM shield provides sufficient neutron flux reduction, being responsible for 5 × 10{sup 6} n/cm{sup 2} s at port interspace, while the EPP gaps and BSM gaps are responsible for 5 × 10{sup 7} n/cm{sup 2} s each. When considering closed upper, lower and lateral neighbour equatorial ports (thus, excluding the cross-talk between ports), a SDDR of 121 μSv/h averaged near the port closure flange was obtained, out of which, only 4 μSv/h are due to the activation of TBMs and TBM shields. Maximum SDDR in the range

  5. Synthesis of the IRSN report on the management of safety and radiological protection of PWRs in unit shutdown. Opinion related to the management by Electricite de France (EDF) of the safety and radiological protection of pressurized water reactors in unit shutdown

    International Nuclear Information System (INIS)

    2013-01-01

    A first report by the IRSN addresses the following topics: implementation of the organisation framework of shutdowns in nuclear power plants, constraints of the multi-year planning of unit shutdown campaigns, protection of the unit shutdown preparation phase, reliability of the initial planning of unit shutdown activities, promotion of the commitment of the shutdown preparation by the new shutdown pilots, the shutdown steering, shutdown performance, return on experience. The issue of external vulnerabilities is also addressed in the conclusion. After mails sent by the ASN, the document contains the opinion issued by the permanent group of experts for nuclear reactors on this management of safety and radiological protection of PWRs in case of unit shutdown. The authors comment the shutdown preparation, the shutdown steering, and the management of organisational changes

  6. Reactivity control system of the high temperature engineering test reactor

    International Nuclear Information System (INIS)

    Tachibana, Yukio; Sawahata, Hiroaki; Iyoku, Tatsuo; Nakazawa, Toshio

    2004-01-01

    The reactivity control system of the high temperature engineering test reactor (HTTR) consists of a control rod system and a reserve shutdown system. During normal operation, reactivity is controlled by the control rod system, which consists of 32 control rods (16 pairs) and 16 control rod drive mechanisms except for the case when the center control rods are removed to perform an irradiation test. In an unlikely event that the control rods fail to be inserted, reserve shutdown system is provided to insert pellets of neutron-absorbing material into the core. Alloy 800H is chosen for the metallic parts of the control rods. Because the maximum temperature of the control rods reaches about 900 deg. C at reactor scrams, structural design guideline and design material data on Alloy 800H are needed for the high temperature design. The design guideline for the HTTR control rod is based on ASME Code Case N-47-21. Design material data is also determined and shown in this paper. Observing the guideline, temperature and stress analysis were conducted; it can be confirmed that the target life of the control rods of 5 years can be achieved. Various tests conducted for the control rod system and the reserve shutdown system are also described

  7. Securing the Future of Seversk and Zheleznogorsk After Reactor Shutdown. Conference Handbook

    International Nuclear Information System (INIS)

    Hund, Gretchen; Stein, Steven L.

    2005-01-01

    Seversk and Zheleznogorsk, two Russian closed nuclear cities, are home to the last three operating plutonium production reactors in Russia. The reactors are now scheduled for shutdown. Closing these reactors presents the world community with a significant nonproliferation achievement, but at the same time poses environmental, economic, and security challenges for the local communities. This conference is an opportunity for the international community to provide crucial support to facilitate these aspects of the plutonium reactor shutdown. Projects proposed complement the reactor shutdown process or assist with worker transition from plutonium production to nonweapons-related careers. Switzerland graciously offered to host the conference with the participation of both the Federal Atomic Energy Agency, Russian Federation and the United States Department of Energy. The one-and-a-half day event was held in Spiez, Switzerland, 8-9 February 2005. Dr. Alec Baer of Switzerland moderated the conference

  8. Experimental Breeder Reactor II inherent shutdown and heat removal tests - test results and analysis

    International Nuclear Information System (INIS)

    Planchon, H.P.; Singer, R.M.; Mohr, D.; Feldman, E.E.; Chang, L.K.; Betten, P.R.

    1985-01-01

    A test program is being conducted to demonstrate that a power producing Liquid Metal Reactor (LMR) can passively remove shutdown heat by natural convection; passively reduce power in response to a loss of reactor flow and passively reduce power in response to a loss of the balance of plant heat sink. Measurements and pretest predictions confirm that natural convection is a reliable, predictable method of shutdown heat removal and suggest that safety-related pumps or pony motors are not necessary for safe, shutdown heat removal in a LMR. Measurements from tests in which reactor flow and heat rejection to the balance of plant were perturbed show that reactivity feedbacks can passively control power and temperature. This data is a basis for additional tests including a complete loss-of-flow without scram and a complete loss of heat sink without scram

  9. 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

  10. 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

  11. Dynamic Analysis of a Floating Vertical Axis Wind Turbine Under Emergency Shutdown Using Hydrodynamic Brake

    DEFF Research Database (Denmark)

    Wang, K.; Hansen, Martin Otto Laver; Moan, T.

    2014-01-01

    Emergency shutdown is always a challenge for an operating vertical axis wind turbine. A 5-MW vertical axis wind turbine with a Darrieus rotor mounted on a semi-submersible support structure was examined in this study. Coupled non-linear aero-hydro-servo-elastic simulations of the floating vertical...... axis wind turbine were carried out for emergency shutdown cases over a range of environmental conditions based on correlated wind and wave data. When generator failure happens, a brake should be applied to stop the acceleration of the rotor to prevent the rotor from overspeeding and subsequent disaster...

  12. 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

  13. Causes of extended shutdown state of 'RA' research reactor in Vinca Institute

    International Nuclear Information System (INIS)

    Pesic, M.; Kolundzija, V.; Ljubenov, V.; Cupac, S.

    2001-01-01

    This paper describes the causes and reasons for extended shutdown state of RA research reactor in the 'Vinca' Institute of Nuclear Sciences. Technical and legal matters that led to decision to stop RA reactor operation in 1984 and further problems related to maintenance and preparation for continuation of operation are given. Influence of nuclear policy of Yugoslav government and the 'Vinca' Institute at prolongation of the reactor shutdown state, as consequence of changing of nuclear programme in the country and the world are discussed and underlined. An overview of the legislation in the field of nuclear safety and regulatory control of radiation sources and radioactive materials in Yugoslavia is presented. (author)

  14. Lack of activation of renal functional reserve predicts the risk of significant renal involvement in systemic sclerosis.

    Science.gov (United States)

    Livi, Riccardo; Guiducci, Serena; Perfetto, Federico; Ciuti, Gabriele; Grifoni, Elisa; Conforti, Letizia; Galluccio, Felice; Moggi Pignone, Alberto; Matucci Cerinic, Marco

    2011-11-01

    To evaluate if defective activation of renal functional reserve (RFR) in systemic sclerosis (SSc) without clinical signs of renal involvement predicts the risk of developing clinically relevant renal damage. Twenty-eight normotensive SSc patients with normal renal function and no urinary abnormalities were submitted to an intravenous amino acid load to activate RFR. Nineteen patients (six with diffuse cutaneous SSc (dcSSc)) had an RFR activation defect, while nine (two with dcSSc) showed normal RFR. All patients were followed up for 5 years, with periodic evaluation of renal function, urinary protein excretion and systemic blood pressure (BP). At admission, patients with normal RFR had lower BP than those with abnormal RFR; no age, disease duration or creatinine clearance (CCr) differences were found. Five years later, patients with abnormal RFR showed, with respect to basal values, a significantly higher CCr reduction than patients with normal RFR (mean percent decrease 15.4 ± 9.5 vs 2.6 ± 3.8, pRFR, 13 (68.4%) showed a CCr reduction of ≥ 2 ml/min/year, with a final CCr of ≤ 70 ml/min in eight cases; two patients developed microalbuminuria and 10 grade 1 or 2 systemic hypertension. Significant CCr reduction rates were found in eight patients with high BP and in five patients who remained normotensive. No patient with normal RFR had proteinuria or high BP during follow-up. Lack of RFR activation is an early sign of renal involvement in SSc, and is a harbinger of an increased risk of developing renal insufficiency and systemic hypertension.

  15. Biomarkers of monitoring and functional reserve of physiological systems over time in HIV: expert opinions for effective secondary prevention.

    Science.gov (United States)

    Andreoni, Massimo; Mussi, Chiara; Bellagamba, Rita; Di Campli, Francesco; Montinaro, Vincenzo; Babiloni, Claudio

    2018-01-01

    HIV-positive individuals are more vulnerable to poor health than HIV-negative individuals. This vulnerability is characterized by a higher risk of several common, age-related health problems, even after adjustment for established risk factors. This expert opinion report aims at identifying the optimal biomarkers for monitoring the structural integrity and function of physiological systems at risk across aging in HIV-seropositive subjects. These biomarkers, readily available locally and relatively cost-effective for clinicians in primary and secondary care, should allow early detection of the first preclinical structural and functional changes in renal, brain, cardiovascular, and skeleton systems or apparatus in HIV subjects across aging. A particular interest of this report is the definition of the concept of biomarker of the "organ functional reserve". This definition emphasizes the fact that some biomarkers for monitoring the molecular, structural and functional integrity of a given organ reflect a level of impairment that is basically irremediable despite effective pharmacological or nonpharmacological intervention.

  16. Diagnostic performance of a novel cadmium-zinc-telluride gamma camera system assessed using fractional flow reserve.

    Science.gov (United States)

    Tanaka, Hirokazu; Chikamori, Taishiro; Tanaka, Nobuhiro; Hida, Satoshi; Igarashi, Yuko; Yamashita, Jun; Ogawa, Masashi; Shiba, Chie; Usui, Yasuhiro; Yamashina, Akira

    2014-01-01

    Although the novel cadmium-zinc-telluride (CZT) camera system provides excellent image quality, its diagnostic value using thallium-201 as assessed on coronary angiography (CAG) and fractional flow reserve (FFR) has not been validated. METHODS AND RESULTS: To evaluate the diagnostic accuracy of the CZT ultrafast camera system (Discovery NM 530c), 95 patients underwent stress thallium-201 single-photon emission computed tomography (SPECT) and then CAG within 3 months. Image acquisition was performed in the supine and prone positions after stress for 5 and 3 min, respectively, and in the supine position at rest for 10 min. Significant stenosis was defined as ≥90% diameter narrowing on visual estimation, or a lesion with <90% and ≥50% stenosis and FFR ≤0.75. To detect individual coronary stenosis, the respective sensitivity, specificity, and accuracy were 90%, 64%, and 78% for left anterior descending coronary artery stenosis, 78%, 84%, and 81% for left circumflex stenosis, and 83%, 47%, and 60% for right coronary artery (RCA) stenosis. The combination of prone and supine imaging had a higher specificity for RCA disease than supine imaging alone (65% vs. 47%), with an improvement in accuracy from 60% to 72%. Using thallium-201 with short acquisition time, combined with prone imaging, CZT SPECT had a high diagnostic yield in detecting significant coronary stenosis as assessed using FFR.

  17. Medical surveillance of nuclear power plant workers during reactor shutdown using whole-body counting and excretion analysis

    International Nuclear Information System (INIS)

    Le Roux-Desmis, C.

    1987-01-01

    After a review of radioactivity basis and radiation protection principles, the various aspects of medical surveillance of nuclear power plant workers during reactor shutdown, are presented. Internal contamination incidents that happened during 1986-1987 shutdown of Paluel reactor are exposed. Internal contamination levels are evaluated using whole-body counting and radionuclide determination in feces and urine and compared with dose limits [fr

  18. 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...

  19. 46 CFR 38.15-20 - Remote shutdowns-TB/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Remote shutdowns-TB/ALL. 38.15-20 Section 38.15-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS LIQUEFIED FLAMMABLE GASES Special Requirements § 38.15-20 Remote shutdowns—TB/ALL. (a) All machinery associated with cargo loading, unloading, or...

  20. Estimation of shutdown heat generation rates in GHARR-1 due to ...

    African Journals Online (AJOL)

    Fission products decay power and residual fission power generated after shutdown of Ghana Research Reactor-1 (GHARR-1) by reactivity insertion accident were estimated by solution of the decay and residual heat equations. A Matlab program code was developed to simulate the heat generation rates by fission product ...

  1. Risk contribution from low power, shutdown, and other operational modes beyond full power

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, D.W.; Brown, T.D. [Sandia National Labs., Albuquerque, NM (United States); Chu, T.L.; Pratt, W.T. [Brookhaven National Lab., Upton, NY (United States); Robinson, R.C. Jr.

    1994-10-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (pressurized water reactor) and Grand Gulf (boiling water reactor), were selected for study. The program consisted of two parallel projects performed by Brookhaven National Laboratory (Surry) and Sandia National Laboratories (Grand Gulf).

  2. 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...

  3. 77 FR 72294 - Reconsideration of Certain New Source and Startup/Shutdown Issues: National Emission Standards...

    Science.gov (United States)

    2012-12-05

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 60 and 63 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...

  4. SCAR - Post-Accident Simulator SIPA with safety analysis code CATHARE-2 and PWR cold shutdown state simulation

    International Nuclear Information System (INIS)

    Farvacque, M.; Faydide, B.; Dufeil, Ph.; Raimond, E.

    2003-01-01

    The use of Cathare in the simulators of pressurized water reactors has been effective since the beginning of the nineties. Scar project is the second stage of the Cathare strategy for the simulators, its main objective is the extension of the field of simulation to the accident situations in cold shutdown states. Work was carried out in 3 major areas: modelling, optimization and integration in the simulator. Throughout the project, the developments were part of a 3 stages validation strategy: -) elementary tests of the developments of new model on the N4 (1450 MW PWR); -) analytical tests and systems to ensure non regression of the validation of the physical laws of the Cathare code during the modifications carried out within the optimization stage; and -) overall tests of the SIPA-CP1 (900 MW PWR) simulator, controlled automatically by programmed scenarios including the transients which are carried out in PWR, the transients of the Regulatory Guides and the accident transients

  5. Fire protection of safe shutdown capability at commercial nuclear power plants

    International Nuclear Information System (INIS)

    Sullivan, K.

    1993-01-01

    The comprehensive industrial safety standards and codes that exist today have evolved from lessons learned through past experience, research results, and improvements in technological capabilities. The current requirements for fire safety features of commercial nuclear power stations operated in the US are a notable example of this practice. Although fire protection has always been an important design requirement, from the aftermath of a serious fire that occurred in 1975 at the Browns Ferry plant, it was learned that the life safety and property protection concerns of the major fire insurance underwriters may not sufficiently encompass nuclear safety issues, particularly with regard to the potential for fire damage to result in the common mode failure of redundant trains of systems, and components important to the safe shutdown of the reactor. Following its investigations into the Browns Ferry fire, the Nuclear Regulatory Commission (NRC) promulgated guidance documents, which ultimately developed into mandatory regulations, necessary to assure the implementation of a fire protection program that would address nuclear safety concerns. The new criteria that evolved, contain prescriptive design features, as well as personnel and administrative requirements the Commission determined to be necessary to provide a defense-in-depth level of protection against the hazards of fire and its associated effects on safety related equipment. These criteria are primarily contained in Appendix R of Title 10 to the Code of Federal Regulations (10 CFR 50). Since 1983, various members of the Department of Nuclear Energy (DNE) at Brookhaven National Laboratory (BNL) have provided technical assistance to the Nuclear Regulatory Commission (NRC) in support of its evaluations of fire protection features implemented at commercial nuclear power stations operated in the US. This paper presents a discussion of the insights gained by the author during his active participation in this area

  6. Chlorophyll a and turbidity patterns over coral reefs systems of La Parguera Natural Reserve,Puerto Rico

    Directory of Open Access Journals (Sweden)

    Ernesto Otero

    2005-05-01

    Full Text Available Studies of temporal and spatial changes in phytoplankton biomass and turbidity provide essential information on coral reef ecosystem function and health.Fluctuation of phytoplankton biomass responds to several factors including nutrient inputs,both anthropogenic and natural,while turbidity is mostly affected by sediment resuspension or transport from terrestrial systems.These parameters can be used as sentinels of significant environmental factors "modifying "coral reef systems.A chlorophyll a concentration (Chl a and turbidity (Turbin situ logger was installed at 10 stations from June 4 to July 7,2003 in La Parguera Natural Reserve (Southwestern Puerto Ricoto assess short-term temporal and geographic variation in patterns of phytoplankton biomass and turbidity at pre-selected sites as part of an interdisciplinary long-term study.Average station Chl a variation was 0.17-1.12 µg l -1 and 0.2-23.4 NTU for Turb.Results indicate that the western near-coastal stations had higher levels of Turb and Chl a .The easternmost mid shelf station,Romero reef,was similar to coastal stations probably due to nutrient and suspended sediment inputs from a source external to our study area to the east,Guánica Bay.Comparisons between different sampling days indicate significant differences between days for most stations suggesting that one-time discrete sampling may not be representative of average water column conditions and illustrate the dynamic nature of coral reef systems.Further work is warranted to assess seasonal changes that integrate short-term (dailyvariability in both Turb and Chl a .Los estudios sobre cambios temporales y espaciales de biomasa fitoplanctónica y de urbidad, proveen información esencial sobre la función y salud de los sistemas arrecifales.Fluctuaciones de la biomasa de fitoplancton responden a factores como entradas de nutrientes de fuentes antropogénicas y/o naturales,mientras que la turbidez responde mayormente a la resuspensi

  7. Establishing a Commercial Reserve Imagery Fleet Obtaining Surge Imagery Capacity from Commercial Remote Sensing Satellite Systems During Crisis

    National Research Council Canada - National Science Library

    Rider, Douglas

    2000-01-01

    .... Congress directed the National Reconnaissance Office and National Imagery and Mapping Agency to investigate commercial satellite imaging systems as a supplement to national reconnaissance systems...

  8. Benchmark Analysis of EBR-II Shutdown Heat Removal Tests

    International Nuclear Information System (INIS)

    2017-08-01

    This publication presents the results and main achievements of an IAEA coordinated research project to verify and validate system and safety codes used in the analyses of liquid metal thermal hydraulics and neutronics phenomena in sodium cooled fast reactors. The publication will be of use to the researchers and professionals currently working on relevant fast reactors programmes. In addition, it is intended to support the training of the next generation of analysts and designers through international benchmark exercises

  9. Shut-down conditions, emergency cooling and essential services

    International Nuclear Information System (INIS)

    Belda, W.

    1977-01-01

    1) Introduction: Summary of system technology and reactor protection equipment. 2) Definitions. 3) LOCA: a) blowdown and refilling phase; b) jet and reaction forces; c) flow and heat transfer behavior in the core; d) behavior of the heater rods; e) core melting. 4) Protection against and during LOCA: a) general measures; b) break of a primary coolant pipe; c) break of a small pipe; d) break of a secondary pipe. (orig.) [de

  10. Shutdown-functionalized nonwoven separator with improved thermal and electrochemical properties for lithium-ion batteries

    Science.gov (United States)

    Kim, Youngkwon; Lee, Won-Yeol; Kim, Ki Jae; Yu, Ji-Sang; Kim, Young-Jun

    2016-02-01

    A shutdown-functionalized nonwoven separator (SFNS) with improved thermal and electrochemical stabilities is prepared by a simple dip coating method for use in lithium-ion battery (LiB) applications. The SFNS shows thermal stability at 200 °C, while providing shutdown functionality at approximately 140 °C, similar to commercial porous polyethylene separators. The surface-coated polymer prevents leakage current problems and in addition, shows air permeability values similar to that of bare nonwoven separators, while maintaining a thickness of about 20 μm, which is a desired attribute of effective separators for LiBs. The SFNS also shows increased electrolyte uptake and higher conductivity, compared to a bare polyethylene separator. Therefore, a cell with the SFNS exhibits higher discharge capacity and better cycle property than that with a porous polyethylene separator. These results suggest that SFNS is an effective separator for high-performance LiBs.

  11. Design, construction, operation, shutdown and surveillance of repositories for solid radioactive wastes in shallow ground

    International Nuclear Information System (INIS)

    1984-01-01

    This report is a part of the IAEA publications under its Programme on Underground Disposal of Radioactive Wastes and is addressed to administrative and technical authorities and specialists who consider the shallow-ground disposal of low- and intermediate-level solid radioactive wastes of short half-lives. The report emphasizes the technological aspects, however it briefly discusses the safety philosophy and regulatory considerations too. The design, construction, operation, shutdown and surveillance of the repositories in shallow ground are considered in some detail, paying special attention to their interrelated aspects. In particular, a review is given of the following aspects: main design and construction considerations in relation to the natural features of the site; design and construction aspects during the repository development process; activities related to operational and post-operational stages of the repository; major steps in repository operation and essential activities in shutdown and operational and post-operational surveillance

  12. Shutdown Dose Rate Analysis for the long-pulse D-D Operation Phase in KSTAR

    Directory of Open Access Journals (Sweden)

    Park Jin Hun

    2017-01-01

    Full Text Available KSTAR is a medium size fully superconducting tokamak. The deuterium-deuterium (D-D reaction in the KSTAR tokamak generates neutrons with a peak yield of 3.5x1016 per second through a pulse operation of 100 seconds. The effect of neutron generation from full D-D high power KSTAR operation mode to the machine, such as activation, shutdown dose rate, and nuclear heating, are estimated for an assurance of safety during operation, maintenance, and machine upgrade. The nuclear heating of the in-vessel components, and neutron activation of the surrounding materials have been investigated. The dose rates during operation and after shutdown of KSTAR have been calculated by a 3D CAD model of KSTAR with the Monte Carlo code MCNP5 (neutron flux and decay photon, the inventory code FISPACT (activation and decay photon and the FENDL 2.1 nuclear data library.

  13. Containment closure time following loss of cooling under shutdown conditions of YGN units 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Seul, Kwang Won; Bang, Young Seok; Kim, Se Won; Kim, Hho Jung [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    1998-12-31

    The YGN Units 3 and 4 plant conditions during shutdown operation were reviewed to identify the possible event scenarios following the loss of shutdown cooling. The thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior. From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determine the containment closure time to prevent the uncontrolled release of fission products to atmosphere. These data provide useful information to the abnormal procedure to cope with the event. 6 refs., 7 figs., 2 tabs. (Author)

  14. 76 FR 2085 - National Estuarine Research Reserve System; North Inlet-Winyah Bay, SC and San Francisco Bay, CA...

    Science.gov (United States)

    2011-01-12

    ... research programs of the reserve; and the plans for future land acquisition and facility development to...; and added significant monitoring of emergent marsh vegetation, invasive species, water quality, and... headquarters building with a 4,500 square foot structure to support research, stewardship, and the coastal...

  15. A Feasibility Study of Sustainable Distributed Generation Technologies to Improve the electrical System on the Duck Valley Reservation

    Energy Technology Data Exchange (ETDEWEB)

    Herman Atkins, Shoshone-Paiute; Mark Hannifan, New West Technologies

    2005-06-30

    A range of sustainable energy options were assessed for feasibility in addressing chronic electric grid reliability problems at Duck Valley IR. Wind power and building energy efficiency were determined to have the most merit, with the Duck Valley Tribes now well positioned to pursue large scale wind power development for on- and off-reservation sales.

  16. Power-system-wide analysis of the benefits of reserve provision from solar photovoltaics in South Africa

    CSIR Research Space (South Africa)

    Bischof-Niemz, T

    2016-06-01

    Full Text Available Reserve provision from standalone solar photovoltaic (PV) power plants has to date not been adopted in practice but has been conceptualised by a number of authors for variable renewable energy (RE) power plants like solar PV and wind. The authors...

  17. 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

  18. Primary loop conditioning and design constraints of Li-Pb cooled tandem mirror reactors during start-up/shutdown operations

    International Nuclear Information System (INIS)

    Taghavi, K.; Ghoniem, N.M.

    1984-01-01

    Engineering considerations during start-up/shutdown operations, and during transients induced by power level variations are considered in this paper. Flooding of cold blanket modules with hot Li-Pb results in severe strain transients that may lead to fatigue failure. The entire primary system, including blanket modules, must therefore be pre-conditoned. We first analyze, and present results of design, for a pre-heat system for the Mirror Advanced Reactor Study (MARS). The pre-heat system is based on helium gas pre-heating for the primary piping and blanket modules. Operational transients induced by partial power variations, or by loss of fusion power are then considered. It is found that the response of the primary loop system is dictated by how fast pumps can accommodate power fluctuations. Pump transients are modeled with a focus on the time dependent power balance through the pump system. Time constants for a representative pump are also derived. Finally, the situation of a total loss of pump power is investigated. In this case, natural circulation due to boyancy pressure differences is shown to be sufficient for the removal of decay afterheat immediately after a loss of pump power. (orig.)

  19. Comparisons of RELAP5-3D Analyses to Experimental Data from the Natural Convection Shutdown Heat Removal Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Bucknor, Matthew; Hu, Rui; Lisowski, Darius; Kraus, Adam

    2016-04-17

    The Reactor Cavity Cooling System (RCCS) is an important passive safety system being incorporated into the overall safety strategy for high temperature advanced reactor concepts such as the High Temperature Gas- Cooled Reactors (HTGR). The Natural Convection Shutdown Heat Removal Test Facility (NSTF) at Argonne National Laboratory (Argonne) reflects a 1/2-scale model of the primary features of one conceptual air-cooled RCCS design. The project conducts ex-vessel, passive heat removal experiments in support of Department of Energy Office of Nuclear Energy’s Advanced Reactor Technology (ART) program, while also generating data for code validation purposes. While experiments are being conducted at the NSTF to evaluate the feasibility of the passive RCCS, parallel modeling and simulation efforts are ongoing to support the design, fabrication, and operation of these natural convection systems. Both system-level and high fidelity computational fluid dynamics (CFD) analyses were performed to gain a complete understanding of the complex flow and heat transfer phenomena in natural convection systems. This paper provides a summary of the RELAP5-3D NSTF model development efforts and provides comparisons between simulation results and experimental data from the NSTF. Overall, the simulation results compared favorably to the experimental data, however, further analyses need to be conducted to investigate any identified differences.

  20. Reliability of functioning and reserves of system, controlling movements with different coordination structure of special health group girl students in physical education process

    Directory of Open Access Journals (Sweden)

    A.A. Pryimakov

    2017-04-01

    Full Text Available Purpose: to study reliability of functioning and reserves of system, controlling movements with different coordination structure of special health group girl students (low health level in physical education process. Material: in the research special health group girl students (n=136, age 17-19 participated. They were divided into 2 groups - control and experimental. The program, directed to increase reliability and reserves of system controlling movements, was realized. It was based on physical exercises of complicated coordination with novelty elements, which were fulfilled under musical accompaniment. The research continued one academic year. Results: in girl students with health problems we registered higher differential thresholds, when reproducing local movements in complicated conditions. They used visual and hearing feedback channels for informing brain’s programming areas about made mistakes. They were worse teachable in training accurate movements. These girl students have less expressed compensation reserves under impact of hindering factors and interferences. It can be interpreted as non-specific crisscross negative response to motor functional system in case of health problems. All these determine reduction of reserve potentials of motor control system. Conclusions: The main reserve potentials’ criteria of control over different coordination structure movements are: quickness of passing to program mechanism of fine movements’ regulation in stable conditions of functioning; power and effectiveness of compensatory reactions, ensuring interference immunity of system, controlling movements under interfering factors; reliability of maintaining movements’ qualitative parameters in optimal range under interfering factors; reduction of sensor interconnections in stable functioning conditions.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. 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

  3. A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels

    Science.gov (United States)

    Xu, Ming; Jiao, Yan; Li, Xiaoming; Cao, Qingfeng; Wang, Xiaoyang

    2015-01-01

    This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations. PMID:26147663

  4. Gullies and dry-valley systems of Kazan as a territorial reserve for the development of the city

    Science.gov (United States)

    Safina, G. R.; Fedorova, V. A.; Medvedeva, R. A.

    2018-01-01

    The article considers possibilities of the use of gully systems of Kazan as a possible resource for territorial development. The city has extensively formed gully and dry valley networks located in different parts of the city. Multi-temporal analysis of cartographic material showed that currently there is an active development of gully systems especially in the central historical part of the city due to the technical capabilities and investment attractiveness. The nature of interaction of gully-dry valley systems and the city is of an overwhelming type.

  5. Application of Systems Engineering to U.S. Department of Energy Privatization Project Selection at the Hanford Nuclear Reservation

    International Nuclear Information System (INIS)

    Layman, John Scott

    1999-01-01

    The privatization efforts at the U.S. Department of Energy's Hanford Nuclear Reservation have been very successful primarily due to a disciplined process for project selection and execution. Early in the development of Privatization at Hanford, the Department of Energy determined that a disciplined alternatives generation and analysis (AGA) process would furnish the candidate projects with the best probability for success. Many factors had to be considered in the selection of projects. Westinghouse Hanford Company was assigned to develop this process and facilitate the selection of the first round of candidate privatization projects. Team members for the AGA process were assembled from all concerned organizations and skill groups. Among the selection criteria were legal, financial and technical considerations which had to be weighed

  6. Power generation scheduling. A free market based procedure with reserve constraints included

    International Nuclear Information System (INIS)

    Huse, Einar Staale

    1998-01-01

    This thesis deals with the short-term scheduling of electric power generation in a competitive market. This involves determination of start-ups and shut-downs, and production levels of all units in all hours of the optimization period, considering unit characteristics and system restrictions. The unit characteristics and restrictions handled are minimum and maximum production levels, fuel cost function, start-up costs, minimum up time and minimum down time. The system restrictions handled are power balance (supply equals demand in all hours) and spinning reserve requirement. The thesis has two main contributions: (1) A new organization of an hourly electric power market that simultaneously sets the price of both energy and reserve power is proposed. A power exchange is used as a trading place for electricity. Its responsibility is to balance supply and demand bids and to secure enough spinning reserve. Routines for bidding and market clearing are developed. (2) A computer programme that simulates the proposed electricity market has been implemented. The program can also be used as a new method for solving the single owner generation scheduling problem. Simulations show that the performance of the program is excellent. Simulations also show that it is possible to obtain efficient schedules through the proposed electricity market. 37 refs., 20 figs., 15 tabs

  7. Power generation scheduling. A free market based procedure with reserve constraints included

    Energy Technology Data Exchange (ETDEWEB)

    Huse, Einar Staale

    1998-12-31

    This thesis deals with the short-term scheduling of electric power generation in a competitive market. This involves determination of start-ups and shut-downs, and production levels of all units in all hours of the optimization period, considering unit characteristics and system restrictions. The unit characteristics and restrictions handled are minimum and maximum production levels, fuel cost function, start-up costs, minimum up time and minimum down time. The system restrictions handled are power balance (supply equals demand in all hours) and spinning reserve requirement. The thesis has two main contributions: (1) A new organization of an hourly electric power market that simultaneously sets the price of both energy and reserve power is proposed. A power exchange is used as a trading place for electricity. Its responsibility is to balance supply and demand bids and to secure enough spinning reserve. Routines for bidding and market clearing are developed. (2) A computer programme that simulates the proposed electricity market has been implemented. The program can also be used as a new method for solving the single owner generation scheduling problem. Simulations show that the performance of the program is excellent. Simulations also show that it is possible to obtain efficient schedules through the proposed electricity market. 37 refs., 20 figs., 15 tabs.

  8. Water quality, meteorological, and nutrient data collected by the the National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) from January 1, 1995 to August 1, 2011 (NODC Accession 0052765)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Estuarine Research Reserve System's System-wide Monitoring Program (NERRS SWMP) collected water quality, meteorological, and nutrient data in 26...

  9. Two computational approaches for Monte Carlo based shutdown dose rate calculation with applications to the JET fusion machine

    International Nuclear Information System (INIS)

    Petrizzi, L.; Batistoni, P.; Migliori, S.; Chen, Y.; Fischer, U.; Pereslavtsev, P.; Loughlin, M.; Secco, A.

    2003-01-01

    In deuterium-deuterium (D-D) and deuterium-tritium (D-T) fusion plasmas neutrons are produced causing activation of JET machine components. For safe operation and maintenance it is important to be able to predict the induced activation and the resulting shut down dose rates. This requires a suitable system of codes which is capable of simulating both the neutron induced material activation during operation and the decay gamma radiation transport after shut-down in the proper 3-D geometry. Two methodologies to calculate the dose rate in fusion devices have been developed recently and applied to fusion machines, both using the MCNP Monte Carlo code. FZK has developed a more classical approach, the rigorous 2-step (R2S) system in which MCNP is coupled to the FISPACT inventory code with an automated routing. ENEA, in collaboration with the ITER Team, has developed an alternative approach, the direct 1 step method (D1S). Neutron and decay gamma transport are handled in one single MCNP run, using an ad hoc cross section library. The intention was to tightly couple the neutron induced production of a radio-isotope and the emission of its decay gammas for an accurate spatial distribution and a reliable calculated statistical error. The two methods have been used by the two Associations to calculate the dose rate in five positions of JET machine, two inside the vacuum chamber and three outside, at cooling times between 1 second and 1 year after shutdown. The same MCNP model and irradiation conditions have been assumed. The exercise has been proposed and financed in the frame of the Fusion Technological Program of the JET machine. The scope is to supply the designers with the most reliable tool and data to calculate the dose rate on fusion machines. Results showed that there is a good agreement: the differences range between 5-35%. The next step to be considered in 2003 will be an exercise in which the comparison will be done with dose-rate data from JET taken during and

  10. Development of Information and Knowledge Architectures and an Associated Framework and Methodology for System Management of a Global Reserve Currency

    Science.gov (United States)

    Cardullo, Mario W.

    2013-01-01

    The global financial system appears to be heading for a major financial crisis. This crisis is being driven by a growing global debt. This crisis is not limited to nations that are heavily in debt such as Greece, Spain, Portugal, Ireland, Italy or Cyprus but to such others as the United States. While there has been a great deal of emphasis on…

  11. Shutdown potential adjustment of modified carbene adducts as additives for lithium ion battery electrolytes

    Science.gov (United States)

    Janssen, Pia; Streipert, Benjamin; Krafft, Roman; Murmann, Patrick; Wagner, Ralf; Lewis-Alleyne, Lesley; Röschenthaler, Gerd-Volker; Winter, Martin; Cekic-Laskovic, Isidora

    2017-11-01

    To improve the intrinsic safety of lithium ion batteries (LIBs) by preventing cells from a thermal runaway, we studied two carbene adduct electrolyte additives. The recently synthesized compounds (1,3-dimethylimidazolidin-2-μm-trifluoroborate (NHC-BF3) and 1,3-dimethylimidazolidin-2-μm-tetrafluorotrifluoromethylphosphate (NHC-PF4CF3)) were investigated on LiNi1/3Co1/3Mn1/3O2 (NMC111) electrodes in Li metal and Li-ion cell setups as overcharge protection shutdown additives in 1M LiPF6 in EC:DEC (3:7, by wt.) electrolyte. By varying the NHC-ligand (-BF3, -PF5, -PF4CF3) in the molecule, the shutdown potential of the investigated carbene adduct electrolyte additives can be tailored for specific applications with different cut-off potentials. NHC-BF3 was identified as a promising candidate for the application with NMC111 electrodes up to 4.4 V vs. Li/Li+, whereas the carbene adduct NHC-PF4CF3 is ideal for the high-voltage application with the NMC-based electrode up to 4.6 V vs. Li/Li+. Next to electrochemical investigations in NMC111/Li and NMC111/graphite cells, Atomic Force Microscopy (AFM) and X-Ray Photoelectron Spectroscopy (XPS) were performed to verify the presence of a decomposition layer on the cathode, responsible for the shutdown effect. Furthermore, it has been proven that the investigated electrolyte additives have no influence on the cell performance under normal conditions in both, Li metal and Li-ion cell setups.

  12. PSA-operations synergism for the advanced test reactor shutdown operations PSA

    International Nuclear Information System (INIS)

    Atkinson, S.A.

    1996-01-01

    The Advanced Test Reactor (ATR) Probabilistic Safety Assessment (PSA) for shutdown operations, cask handling, and canal draining is a successful example of the importance of good PSA-operations synergism for achieving a realistic and accepted assessment of the risks and for achieving desired risk reduction and safety improvement in a best and cost-effective manner. The implementation of the agreed-upon upgrades and improvements resulted in the reductions of the estimated mean frequency for core or canal irradiated fuel uncovery events, a total reduction in risk by a factor of nearly 1000 to a very low and acceptable risk level for potentially severe events

  13. CMS DAQ current and future hardware upgrades up to post Long Shutdown 3 (LS3) times

    CERN Document Server

    Racz, Attila; Behrens, Ulf; Branson, James; Chaze, Olivier; Cittolin, Sergio; Contescu, Cristian; da Silva Gomes, Diego; Darlea, Georgiana-Lavinia; Deldicque, Christian; Demiragli, Zeynep; Dobson, Marc; Doualot, Nicolas; Erhan, Samim; Fulcher, Jonathan Richard; Gigi, Dominique; Gladki, Maciej; Glege, Frank; Gomez-Ceballos, Guillelmo; Hegeman, Jeroen; Holzner, Andre; Janulis, Mindaugas; Lettrich, Michael; Meijers, Frans; Meschi, Emilio; Mommsen, Remigius K; Morovic, Srecko; O'Dell, Vivian; Orn, Samuel Johan; Orsini, Luciano; Papakrivopoulos, Ioannis; Paus, Christoph; Petrova, Petia; Petrucci, Andrea; Pieri, Marco; Rabady, Dinyar; Reis, Thomas; Sakulin, Hannes; Schwick, Christoph; Simelevicius, Dainius; Vazquez Velez, Cristina; Vougioukas, Michail; Zejdl, Petr

    2017-01-01

    Following the first LHC collisions seen and recorded by CMS in 2009, the DAQ hardware went through a major upgrade during LS1 (2013- 2014) and new detectors have been connected during 2015-2016 and 2016-2017 winter shutdowns. Now, LS2 (2019-2020) and LS3 (2024-mid 2026) are actively being prepared. This paper shows how CMS DAQ hardware has evolved from the beginning and will continue to evolve in order to meet the future challenges posed by High Luminosity LHC (HL-LHC) and the CMS detector evolution. In particular, post LS3 DAQ architectures are focused upon.

  14. Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1: Analysis of core damage frequency from internal fire events for Plant Operational State 5 during a refueling outage. Volume 3

    International Nuclear Information System (INIS)

    Lambright, J.; Yakle, J.

    1994-07-01

    This report, Volume 3, presents the details of the analysis of core damage frequency due to fire during shutdown Plant Operational State 5 at the Grand Gulf Nuclear Station. Insights from previous fire analyses (Peach Bottom, Surry, LaSalle) were used to the greatest extent possible in this analysis. The fire analysis was fully integrated utilizing the same event trees and fault trees that were used in the internal events analysis. In assessing shutdown risk due to fire at Grand Gulf, a detailed screening was performed which included the following elements: (a) Computer-aided vital area analysis; (b) Plant inspections; (c) Credit for automatic fire protection systems; (d) Recovery of random failures; (e) Detailed fire propagation modeling. This screening process revealed that all plant areas had a negligible (<1.0E-8 per year) contribution to fire-induced core damage frequency

  15. System-Level Operational and Adequacy Impact Assessment of Photovoltaic and Distributed Energy Storage, with Consideration of Inertial Constraints, Dynamic Reserve and Interconnection Flexibility

    Directory of Open Access Journals (Sweden)

    Lingxi Zhang

    2017-07-01

    Full Text Available The growing penetration of solar photovoltaic (PV systems requires a fundamental understanding of its impact at a system-level. Furthermore, distributed energy storage (DES technologies, such as batteries, are attracting great interest owing to their ability to provide support to systems with large-scale renewable generation, such as PV. In this light, the system-level impacts of PV and DES are assessed from both operational and adequacy perspectives. Different control strategies for DES are proposed, namely: (1 centralised, to support system operation in the presence of increasing requirements on system ramping and frequency control; and (2 decentralised, to maximise the harnessing of solar energy from individual households while storing electricity generated by PV panels to provide system capacity on request. The operational impacts are assessed by deploying a multi-service unit commitment model with consideration of inertial constraints, dynamic reserve allocation, and interconnection flexibility, while the impacts on adequacy of supply are analysed by assessing the capacity credit of PV and DES through different metrics. The models developed are then applied to different future scenarios for the Great Britain power system, whereby an electricity demand increase due to electrification is also considered. The numerical results highlight the importance of interconnectors to provide flexibility. On the other hand, provision of reserves, as opposed to energy arbitrage, from DES that are integrated into system operation is seen as the most effective contribution to improve system performance, which in turn also decreases the role of interconnectors. DES can also contribute to providing system capacity, but to an extent that is limited by their individual and aggregated energy availability under different control strategies.

  16. Safe shutdown of Defense Program facilities at the Mound Plant, Miamisburg, Ohio

    International Nuclear Information System (INIS)

    Anderson, H.F.; Bantz, P.D.; Luthy, D.F.

    1996-01-01

    The Mound Plant was one of several production sites in the US Department of Energy's Defense Programs (DP) Weapons Complex. As a result of the downsizing of the weapons program, certain operations at Mound are being transferred to other DOE sites and the DP buildings at Mound are being shutdown. The objectives of the program are to reduce the hazardous and financial liabilities to DOE and to foster the reuse of facilities for economic development. The overall program is described. The process began with the categorization of excess DP buildings into three groups depending on their anticipated future use. The draft DOE/EM-60 Acceptance Criteria were used to develop a detailed shutdown checklist as the foundation of the process. The overall program budget, schedule, ad options for disposition of materials and components is presented. Accomplishments in FY94 and FY95 are described. By the end of FY95, all excess energetic materials and components, all excess chemicals (from non-radiation areas) and significant amounts of radioactive materials have been removed from the site. By the end of FY95, 47 of the 72 buildings in the program have been taken through all ten of the draft EM-60 acceptance criteria. Lessons learned, based on experience at Mound to date, are summarized

  17. Dynamic Response of AP1000 Nuclear Island Due to Safe Shutdown Earthquake Loading

    Directory of Open Access Journals (Sweden)

    Gan Buntara S.

    2017-01-01

    Full Text Available AP1000 is a standard nuclear power plant developed by Westinghouse and its partners by using an advanced passive safety feature. Among the five principle building structures, namely the nuclear island, turbine building, annex building, diesel generator building and radwaste building, the safety of the nuclear island building is the most concerned. This paper investigates the dynamic response of the nuclear island building of the AP1000 plant subjected to safe shutdown earthquake loadings. A finite element model for the building, which is assumed to be built in a hard-rock base, is developed and its dynamic response is computed with the aid of the commercial finite element package ANSYS. The dynamic characteristics, including the natural frequencies, the vibration modes, and the time histories for displacements, velocities, and accelerations of the building are obtained for two typical safe shutdown earthquakes, El Centro and Kobe earthquakes. The dynamic behavior of the building due to the earthquakes and its safety is examined and highlighted.

  18. A scoping evaluation of severe accidents at Surry and Grand Gulf Nuclear Power Plants resulting from earthquakes during shutdown conditions

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Davis, P.R.

    1991-01-01

    This report explores the likelihood of seismic-initiated core damage accidents during refueling shutdown conditions at two nuclear power plants, Surry Unit I and Grand Gulf Unit 1. The effort is scoping in character, and has been performed primarily to establish if a potential problem exists sufficient to justify a more rigorous and more quantitative evaluation. A summary is presented of the important conclusions that have been reached. The most important conclusion is that the core-damage frequencies for earthquake-initiated accidents during shutdown at both Surry Unit I and Grand Gulf Unit I are found to be low in absolute terms. The reasons for this are that in their ability to respond to earthquakes during shutdowns, the plants both have large seismic capacities, well above their design-basis levels; and also that both sites enjoy among the lowest seismic hazards of any LWR sites in the US

  19. 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

  20. Calculation of balancing reserves incorporating wind power into the Hydro-Quebec system over the time horizon of 1 to 48 hours

    Energy Technology Data Exchange (ETDEWEB)

    Menemenlis, N.; Huneault, M. [IREQ, Varennes, QC (Canada); Bourret, J. [Hydro-Quebec Distribution, Montreal, QC (Canada). Dir. Approvisionnement en Electricite; Robitaille, A. [Hydro-Quebec Production, Montreal, PQ (Canada). Dir. Planification de la Production Eolienne

    2009-07-01

    Hydro-Quebec (HQ), the main electricity provider in Quebec, Canada, serves a peak load of 37000 MW, 95% provided by hydroelectric generation. It is in the process of incorporating 3000 MW of wind power into its system, reaching 4000 MW by the year 2015. As wind power generation is accompanied by inherent uncertainties, HQ plans to revise its balancing reserves in order to mitigate the consequences of inherent prediction errors. To this end, HQ has put forward a novel methodology calculating the level of these balancing reserves, over the time horizon of 1-48 hours, based on the risk that the load will exceed the committed generation capacity. The methodology, reported in this paper, requires as input the statistical characteristics of the load and wind generation forecast errors and of the generation outages. The implementation details of this methodology as well as discussion of the nature of the results are given. (orig.)

  1. Spins, Stalls, and Shutdowns: Pitfalls of Qualitative Policing and Security Research

    Directory of Open Access Journals (Sweden)

    Randy K. Lippert

    2015-11-01

    Full Text Available This article explores key elements of qualitative research on policing and security agencies, including barriers encountered and strategies to prevent them. While it is oft-assumed that policing/security agencies are difficult to access due to their clandestine or bureaucratic nature, this article demonstrates this is not necessarily the case, as access was gained for three distinct qualitative research projects. Yet, access and subsequent research were not without pitfalls, which we term security spins, security stalls, and security shutdowns. We illustrate how each was encountered and argue these pitfalls are akin to researchers falling into risk categories, not unlike those used by policing/security agents in their work. Before concluding we discuss methodological strategies for scholars to avoid these pitfalls and to advance research that critically interrogates the immense policing/security realm. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1601108

  2. LS1 “First Long Shutdown of LHC and its Injector Chains”

    CERN Multimedia

    Foraz, K; Barberan, M; Bernardini, M; Coupard, J; Gilbert, N; Hay, D; Mataguez, S; McFarlane, D

    2014-01-01

    The LHC and its Injectors were stopped in February 2013, in order to maintain, consolidate and upgrade the different equipment of the accelerator chain, with the goal of achieving LHC operation at the design energy of 14 TeV in the centre-of-mass. Prior to the start of this First Long Shutdown (LS1), a major effort of preparation was performed in order to optimize the schedule and the use of resources across the different machines, with the aim of resuming LHC physics in early 2015. The rest of the CERN complex will restart beam operation in the second half of 2014. This paper presents the schedule of the LS1, describes the organizational set-up for the coordination of the works, the main activities, the different main milestones, which have been achieved so far, and the decisions taken in order to mitigate the issues encountered.

  3. Monitoring the risk of loss of heat sink during plant shutdowns at Bruce Generating Station 'A'

    International Nuclear Information System (INIS)

    Krishnan, K.S.; Mancuso, F.; Vecchiarelli, D.

    1996-01-01

    A relatively simple loss of shutdown heat sink fault tree model has been developed and used during unit outages at Bruce Nuclear Generation Station 'A' to assess, from a risk and reliability perspective, alternative heat sink strategies and to aid in decisions on allowable outage configurations. The model is adjusted to reflect the various unit configurations planned during a specific outage, and identifies events and event combinations leading to loss of fuel cooling. The calculated failure frequencies are compared to the limits consistent with corporate and international public safety goals. The importance measures generated by the interrogation of the fault tree model for each outage configuration are also used to reschedule configurations with high fuel damage frequency later into the outage and to control the configurations with relatively high probability of fuel damage to short intervals at the most appropriate time into the outage. (author)

  4. Main approaches to choice of decontamination methods in case of nuclear power plant shutdown

    International Nuclear Information System (INIS)

    Tarasov, V.M.; Syrkus, M.N.

    1991-01-01

    Selection criteria for optimal decontamination technology in case of nuclear power plant shutdown are considered. It is shown that technology evaluation from the viewpoint of observance of required precautionary measures is performed during the first stage of operation followed by analysis of process operational characteristics. The next stage relates to risk analysis of equipment, technological process and structure failures. The selection process is followed then according to criteria of decontamination duration, complexity level of control process and availability of qualified personnel, as well as complexity and composition of radioactive waste conditioning. Further follows decontamination technology evaluation from the viewpoint of its impact on personnal health and enviroment. Cost-benefit ratio resulting from introduction of technologies under consideration are determined at the final stage

  5. Selection of equipment for safe shutdown in the event of earthquake

    International Nuclear Information System (INIS)

    Romano Gomez, J.; Perez Alcaniz, T.; Esteban Barriendos, M.

    1993-01-01

    This paper presents the work carried out at the Almaraz Nuclear Power Plant for selecting equipment that contributes to reactor safe shutdown in the event of earthquake. The objective was to comply with the requirements defined by the US NRC in Generic Letter 87-02, 'Verification of Seismic Adequacy of Mechanical and Electrical Equipment in Operating Reactors'. The analysis framework and the method applied followed the generic procedures prepared by the Seismic Qualification Utility Group of which Almaraz NPP is a member, along with other Spanish power plants. The equipment selected shall be subjected to the Application Programme of the above-mentioned Generic Letter. The aim has been to cover the objectives of the programme and, at the same time, to ensure compatibility with plant operating procedures. (author)

  6. Production and Quality Assurance of Main Busbar Interconnection Splices during the LHC 2008-2009 Shutdown.

    CERN Document Server

    Bertinelli, F; Dalin, J-M; Fessia, P; Flora, R H; Heck, S; Pfeffer, H; Prin, H; Scheuerlein, C; Thonet, P; Tock, J-P; Williams, L

    2011-01-01

    The main busbar interconnection splices of the Large Hadron Collider are assembled by inductive soldering of the Rutherford type cables and the copper profiles of the stabilizer. Following the September 2008 incident, the assembly process and the quality assurance have been improved, with new measurement and diagnostics methods introduced. In the 2008-2009 shutdown the resistance both in the superconducting and in the normal conducting states have been the focus for improvements. The introduction of gamma radiography has allowed the visualization of voids between cable and stabilizer. It is now known that during the standard soldering heating cycle solder is lost from the busbar extremities adjacent to the splice profiles, leaving parts of the cable in poor contact with the stabilizer. A room temperature resistance measurement has been introduced as a simple, non-destructive test to measure the electrical continuity of the splice in its normal conducting state. An ultrasonic test has been performed systematic...

  7. The Chernobyl plant shutdown; L'arret de la centrale de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    The Chernobylsk-1 reactor, operational in september 1977 has been stopped in november 1996; the Chernobylsk-2 reactor started in november 1978 is out of order since 1991 following a fire. The Chernobylsk-3 reactor began in 1981. During the last three years it occurs several maintenance operations that stop it. In june 2000, the Ukrainian authorities decided to stop it definitively on the 15. of december (2000). This file handles the subject. it is divided in four chapters: the first one gives the general context of the plant shutdown, the second chapter studies the supporting projects to stop definitively the nuclear plant, the third chapter treats the question of the sarcophagus, and the fourth and final chapter studies the consequences of the accident and the contaminated territories. (N.C.)

  8. 46 CFR 32.50-35 - Remote manual shutdown for internal combustion engine driven cargo pump on tank vessels-TB/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Remote manual shutdown for internal combustion engine... for Cargo Handling § 32.50-35 Remote manual shutdown for internal combustion engine driven cargo pump on tank vessels—TB/ALL. (a) Any tank vessel which is equipped with an internal combustion engine...

  9. Risk contribution from low power, shutdown, and other operational modes beyond full power

    International Nuclear Information System (INIS)

    Whitehead, D.W.; Brown, T.D.; Chu, T.L.; Pratt, W.T.

    1995-01-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power and comparing estimated core damage frequencies, important accident sequences, and other qualitative and quantitative results with full power accidents as assessed in NUREG-1150. The scope included a Level 3 probabilistic risk assessment (PRA) for traditional internal events and a Level 1 PRA on fire, flooding, and seismically induced core damage sequences. A phased approach was used in Level 1. In Phase 1 the concept of plant operational states (POSs) was developed to provide a better representation of the plant as it transitions from power to nonpower operation. This included a coarse screening analysis of all POSs to identify vulnerable plant configurations, to characterize (on a high, medium, or low basis) potential frequencies of core damage accidents, and to provide a foundation for a detailed Phase 2 analysis. In Phase 2, selected POSs from both Grand Gulf and Surry were chosen for detailed analysis. For Grand Gulf, POS 5 (approximately cold shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage was selected. For Surry, three POSs representing the time the plant spends in midloop operation were chosen for analysis. These included POS 6 and POS 10 of a refueling outage and POS 6 of a drained maintenance outage. Level 1 and Level 2/3 results from both the Surry and Grand Gulf analyses are presented

  10. Simulation of runaway electron generation during plasma shutdown by impurity injection

    Energy Technology Data Exchange (ETDEWEB)

    Feher, Tamas

    2011-03-15

    Disruptions are dangerous instabilities in tokamaks that should be avoided or mitigated. One possible disruption mitigation method is to inject impurities into the plasma to shut it down in a controlled way. Runaway Electrons (REs) can be generated after the plasma is cooled down by the impurities and these electrons can damage the tokamak. In this work a simulation code is developed to investigate different disruption mitigation scenarios. The response of the bulk plasma, more precisely the temperature evolution of electrons, deuterium and impurity ions are described by energy balance equations in a 1D cylindrical plasma model. The induction and resistive diffusion of electric field is calculated. RE generation rates are used to calculate the runaway current. The Dreicer, hot-tail and avalanche effect is taken into account and a simple model for RE losses is also included. RE generation is studied in JET-like plasmas during pellet injection. Carbon pellets cause effective cooling but these scenarios are prone to runaway generation. A mixture of argon and deuterium gas could be used for safe shutdown without RE generation. In ITER the hot-tail RE generation process becomes important, and the simulation is therefore extended to take this into account. Shutdown scenarios with different concentration of neon and argon impurities were tested in ITER-like plasmas. To simplify the problem the impurity injection into the plasma is not modeled in these cases, only the response of the bulk plasma. The avalanche process cannot be suppressed in a simple way and would produce high runaway current. It can be avoided if some runaway loss phenomenon is included in the simulations, like diffusion due to magnetic perturbations

  11. Risk contribution from low power, shutdown, and other operational modes beyond full power

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, D.W.; Brown, T.D. [Sandia National Labs., Albuquerque, NM (United States); Chu, T.L. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1995-04-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power and comparing estimated core damage frequencies, important accident sequences, and other qualitative and quantitative results with full power accidents as assessed in NUREG-1150. The scope included a Level 3 probabilistic risk assessment (PRA) for traditional internal events and a Level 1 PRA on fire, flooding, and seismically induced core damage sequences. A phased approach was used in Level 1. In Phase 1 the concept of plant operational states (POSs) was developed to provide a better representation of the plant as it transitions from power to nonpower operation. This included a coarse screening analysis of all POSs to identify vulnerable plant configurations, to characterize (on a high, medium, or low basis) potential frequencies of core damage accidents, and to provide a foundation for a detailed Phase 2 analysis. In Phase 2, selected POSs from both Grand Gulf and Surry were chosen for detailed analysis. For Grand Gulf, POS 5 (approximately cold shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage was selected. For Surry, three POSs representing the time the plant spends in midloop operation were chosen for analysis. These included POS 6 and POS 10 of a refueling outage and POS 6 of a drained maintenance outage. Level 1 and Level 2/3 results from both the Surry and Grand Gulf analyses are presented.

  12. Risk contribution from low power, shutdown, and other operational modes beyond full power

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, D.W.; Brown, T.D.; Chu, T.L.; Pratt, W.T.

    1995-01-01

    During 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low power and shutdown operations. Two plants, Surry (a pressurized water reactor) and Grand Gulf (a boiling water reactor), were selected for study by Brookhaven National Laboratory and Sandia National Laboratories, respectively. The program objectives included assessing the risks of severe accidents initiated during plant operational states other than full power and comparing estimated core damage frequencies, important accident sequences, and other qualitative and quantitative results with full power accidents as assessed in NUREG-1150. The scope included a Level 3 probabilistic risk assessment (PRA) for traditional internal events and a Level 1 PRA on fire, flooding, and seismically induced core damage sequences. A phased approach was used in Level 1. In Phase 1 the concept of plant operational states (POSs) was developed to provide a better representation of the plant as it transitions from power to nonpower operation. This included a coarse screening analysis of all POSs to identify vulnerable plant configurations, to characterize (on a high, medium, or low basis) potential frequencies of core damage accidents, and to provide a foundation for a detailed Phase 2 analysis. In Phase 2, selected POSs from both Grand Gulf and Surry were chosen for detailed analysis. For Grand Gulf, POS 5 (approximately cold shutdown as defined by Grand Gulf Technical Specifications) during a refueling outage was selected. For Surry, three POSs representing the time the plant spends in midloop operation were chosen for analysis. These included POS 6 and POS 10 of a refueling outage and POS 6 of a drained maintenance outage. Level 1 and Level 2/3 results from both the Surry and Grand Gulf analyses are presented.

  13. Report of a consultants meeting on accidents during shutdown conditions for WWER nuclear power plants. Extrabudgetary programme on the safety of WWER NPPs

    International Nuclear Information System (INIS)

    1996-07-01

    The main objectives of the meeting were to exchange information on the operational occurrences, studies performed and countermeasures taken for the accidents during shutdown for WWERs, and to define the necessity and directions of the further activities which may promote the improvement of WWER safety under shutdown conditions. The consultants have discussed some aspects concerning vulnerability of safety functions during shutdown conditions, several steps required to performed accident analysis and selected operational aspects for shutdown conditions. The discussion was supported by an evaluation of selected operational occurrences. The consultants have agreed that the discussion during the meeting in major parts is relevant to all the WWER designs (i.e. WWER-1000, WWER-440/213 and WWER-440/230). As for the plant conditions, the consultants have agreed to bound the discussion mainly by the cold shutdown and refuelling modes. Refs, figs, tabs

  14. Estimation of the economic impact of temperature changes induced by a shutdown of the thermohaline circulation: an application of FUND

    NARCIS (Netherlands)

    Link, P.M.; Tol, R.S.J.

    2011-01-01

    The integrated assessment model FUND 2.8n is applied in an assessment to estimate the magnitude of the general market and non-market impacts of temperature changes caused by a possible shutdown of the thermohaline circulation (THC). The monetized impacts of this change in environmental conditions

  15. 78 FR 79709 - Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown...

    Science.gov (United States)

    2013-12-31

    ...] [FR Doc No: 2013-31317] NUCLEAR REGULATORY COMMISSION [Docket No. 50-302; NRC-2013-0283] Duke Energy Florida, Inc., Crystal River Unit 3 Nuclear Generating Plant Post-Shutdown Decommissioning Activities Report AGENCY: Nuclear Regulatory Commission (NRC). ACTION: Notice of receipt; availability; public...

  16. Verification and validation of the R2Smesh approach for the calculation of high resolution shutdown dose rate distributions

    Czech Academy of Sciences Publication Activity Database

    Majerle, Mitja; Leichtle, D.; Fischer, U.; Serikov, A.

    2012-01-01

    Roč. 87, 5-6 (2012), s. 443-447 ISSN 0920-3796 Institutional support: RVO:61389005 Keywords : MCNP * FISPACT * shutdown dose rate Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 0.842, year: 2012

  17. The deep hydrogeologic flow system underlying the Oak Ridge Reservation -- Assessing the potential for active groundwater flow and origin of the brine

    Energy Technology Data Exchange (ETDEWEB)

    Nativ, R. [Hebrew Univ. of Jerusalem (Israel). Dept. of Soil and Water Sciences; Halleran, A.; Hunley, A. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.

    1997-08-01

    The deep hydrogeologic system underlying the Oak Ridge Reservation (ORR) contains contaminants such as radionuclides, heavy metals, nitrates, and organic compounds. The groundwater in the deep system is saline and has been considered to be stagnant in previous studies. This study was designed to address the following questions: is groundwater in the deep system stagnant; is contaminant migration controlled by diffusion only or is advection a viable mechanism; where are the potential outlet points? On the basis of existing and newly collected data, the nature of saline groundwater flow and potential discharge into shallow, freshwater systems was assessed. Data used for this purpose included (1) spatial and temporal pressures and hydraulic heads measured in the deep system, (2) hydraulic parameters of the formations in question, (3) spatial and temporal temperature variations at depth, and (4) spatial and temporal chemical and isotopic composition of the saline groundwater. The observations suggest that the saline water contained at depth is old but not isolated (in terms of recharge and discharge) from the overlying active, freshwater-bearing units. Influx of recent water does occur. Groundwater volumes involved in this flow are likely to be small. The origin of the saline groundwater was assessed by using existing and newly acquired chemical and isotopic data. The proposed model that best fits the data is modification of residual brine from which halite has been precipitated. Other models, such as ultrafiltration and halite dissolution, were also evaluated.

  18. Scalability of the natural convection shutdown heat removal test facility (NSTF) data to VHTR/NGNP RCCS designs

    International Nuclear Information System (INIS)

    Vilim, R.B.; Feldman, E.E.

    2007-01-01

    Passive safety in the Very High Temperature Reactor (VHTR) is strongly dependent on the thermal performance of the Reactor Cavity Cooling System (RCCS). Scaled experiments performed in the Natural Shutdown Test Facility (NSTF) are to provide data for assessing and/or improving computer code models for RCCS phenomena. Design studies and safety analyses that are to support licensing of the VHTR will rely on these models to achieve a high degree of certainty in predicted design heat removal rate. To guide in the selection and development of an appropriate set of experiments a scaling analysis has been performed for the air-cooled RCCS option. The goals were to (1) determine the phenomena that dominate the behavior of the RCCS, (2) determine the general conditions that must be met so that these phenomena and their relative importance are preserved in the experiments, (3) identify constraints specific to the NSTF that potentially might prevent exact similitude, and (4) then to indicate how the experiments can be scaled to prevent distortions in the phenomena of interest. The phenomena identified as important to RCCS operation were also the subject of a recent PIRT study. That work and the present work collectively indicate that the main phenomena influencing RCCS heat removal capability are (1) radiation heat transport from the vessel to the air ducts, (2) the integral effects of momentum and heat transfer in the air duct, (3) buoyancy at the wall inside the air duct giving rise to mixed convection, and (4) multidimensional effects inside the air duct caused by non-uniform circumferential heat flux and non-circular geometry

  19. Fractional Reserve Banking: Some Quibbles

    OpenAIRE

    Bagus, Philipp; Howden, David

    2010-01-01

    We explore several unaddressed issues in George Selgin’s (1988) claim that the best monetary system to maintain monetary equilibrium is a fractional reserve free banking one. The claim that adverse clearing balances would limit credit expansion in a fractional reserve free banking system is more troublesome than previously reckoned. Both lengthened clearing periods and interbank agreements render credit expansion unrestrained. “The theory of free banking” confuses increases in money held with...

  20. Shutdown dose rate analysis for the European TBM system in ITER

    Czech Academy of Sciences Publication Activity Database

    Pereslavtsev, P.; Fischer, U.; Grosse, D.; Leichtle, D.; Majerle, Mitja

    2012-01-01

    Roč. 87, 5/6 (2012), s. 493-497 ISSN 0920-3796. [10th International Symposium on Fusion Nuclear Technology (ISFNT). Portland, Oregon, 11.09.2011-16.09.2011] Institutional research plan: CEZ:AV0Z10480505 Keywords : ITER * test blanket module * dose rate * neutron streaming Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.842, year: 2012 http://ac.els-cdn.com/S0920379612000087/1-s2.0-S0920379612000087-main.pdf?_tid=5dbc1c80-9d09-11e2-b0cd-00000aab0f02&acdnat=1365067612_87a914bcde868dedc633d192db7d6b7b

  1. Perspectives of the use of experience of preparation of reserve in cyclic disciplines in the system of the long-term training in team games

    Directory of Open Access Journals (Sweden)

    Maksimenko I.G.

    2012-06-01

    Full Text Available Purpose of work to define approaches to the construction of long-term preparation of reserve in cyclic disciplines. Also to ground perspective directions of their use in a training process in the playing types of sport. Questioning, conversations and questionnaires of leading specialists (17 trainers and sportsmen is conducted (80 athletes. It is marked that one of lacks of the traditional system of preparation of sportsmen is the insufficient providing of training process information technologies. It is set that in the cyclic types of sport the sharp is enough there is a problem of planning of loadings in macrocycle of training of young sportsmen. It is rotined that to the features of construction of training process in cyclic kinds it is necessary to take application of individual approach. The possible ways of decision of problem of optimization of long-term training of reserve are presented in sporting games. Attention is accented on the necessity of realization in practice of theoretical positions which are related to all of the stages of the long-term training.

  2. Evaluating Steam Generator Tubing Corrosion through Shutdown Nickel and Cobalt Releases

    International Nuclear Information System (INIS)

    Marks, Chuck; Little, Mike; Krull, Peter; Dennis Hussey; Kenny Epperson

    2012-09-01

    During power operation in PWRs, steam generator tubing corrodes. In PWRs with nickel alloy steam generator tubing this leads to the release of nickel into the coolant. While not structurally significant, this process leads to corrosion product deposition on the fuel surfaces that can threaten fuel integrity, provide a site for boron precipitation, and, through activation and subsequent release, lead to increased out-of-core radiation fields. During shutdown, decreases in temperature and pH and an increase in the oxidation potential lead to dissolution of some corrosion products from the core. This work evaluated the masses of corrosion products released during shutdown as a proxy for steam generator tubing corrosion rates. The masses were evaluated for trends with time (e.g., the number of cycles) and for the influence of design and operating features such as tubing manufacturer, plant design (e.g., three loop versus four loop), and operating chemistry program. This project utilized the EPRI PWR Chemistry Monitoring and Assessment database. Data from over 20 units, many over several cycles, were assessed. The focus was on corrosion product release from Alloy 690TT tubing and all data were from units that had replaced steam generators. Data were analyzed using models developed from corrosion rate test data reported in the literature with a heavy reliance on data from the EDF BOREAL testing. The most striking result of this analysis was a clear division between plants that exhibited corrosion with a falling rate (i.e., following an exponential decay as has been observed, for example, in the BOREAL testing) and those that showed a constant corrosion rate, sustained for many outages. This difference appears to be most closely correlated with the manufacturer of the tubing. Within the two distinct plant groups (decaying corrosion rate and constant corrosion rate), details of the trends were evaluated for correlation with zinc addition history, plant type, and operating

  3. Common characterization of variability and forecast errors of variable energy sources and their mitigation using reserves in power system integration studies

    Energy Technology Data Exchange (ETDEWEB)

    Menemenlis, N.; Huneault, M. [IREQ, Varennes, QC (Canada); Robitaille, A. [Dir. Plantif. de la Production Eolienne, Montreal, QC (Canada). HQ Production; Holttinen, H. [VTT Technical Research Centre of Finland, VTT (Finland)

    2012-07-01

    This In this paper we define and characterize the two random variables, variability and forecast error, over which uncertainty in power systems operations is characterized and mitigated. We show that the characterization of both these variables can be carried out with the same mathematical tools. Furthermore, this common characterization of random variables lends itself to a common methodology for the calculation of non-contingency reserves required to mitigate their effects. A parallel comparison of these two variables demonstrates similar inherent statistical properties. They depend on imminent conditions, evolve with time and can be asymmetric. Correlation is an important factor when aggregating individual wind farm characteristics in forming the distribution of the total wind generation for imminent conditions. (orig.)

  4. Cognitive reserve in aging.

    Science.gov (United States)

    Tucker, A M; Stern, Y

    2011-06-01

    Cognitive reserve explains why those with higher IQ, education, occupational attainment, or participation in leisure activities evidence less severe clinical or cognitive changes in the presence of age-related or Alzheimer's disease pathology. Specifically, the cognitive reserve hypothesis is that individual differences in how tasks are processed provide reserve against brain pathology. Cognitive reserve may allow for more flexible strategy usage, an ability thought to be captured by executive functions tasks. Additionally, cognitive reserve allows individuals greater neural efficiency, greater neural capacity, and the ability for compensation via the recruitment of additional brain regions. Taking cognitive reserve into account may allow for earlier detection and better characterization of age-related cognitive changes and Alzheimer's disease. Importantly, cognitive reserve is not fixed but continues to evolve across the lifespan. Thus, even late-stage interventions hold promise to boost cognitive reserve and thus reduce the prevalence of Alzheimer's disease and other age-related problems.

  5. 40 CFR 63.9306 - What are my continuous parameter monitoring system (CPMS) installation, operation, and...

    Science.gov (United States)

    2010-07-01

    ... device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect...) Automatic shutdown system. Use an automatic shutdown system in which the engine testing operation is stopped...

  6. Biosphere reserves: Attributes for success.

    Science.gov (United States)

    Van Cuong, Chu; Dart, Peter; Hockings, Marc

    2017-03-01

    Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to the development of a new strategy in 1995 (the Seville Strategy) to enhance the operation of the network of reserves. An evaluation of effectiveness of management of the biosphere reserve network was called for as part of this strategy. Expert opinion was assembled through a Delphi Process to identify successful and less successful reserves and investigate common factors influencing success or failure. Ninety biosphere reserves including sixty successful and thirty less successful reserves in 42 countries across all five Man and the Biosphere Program regions were identified. Most successful sites are the post-Seville generation while the majority of unsuccessful sites are pre-Seville that are managed as national parks and have not been amended to conform to the characteristics that are meant to define a biosphere reserve. Stakeholder participation and collaboration, governance, finance and resources, management, and awareness and communication are the most influential factors in the success or failure of the biosphere reserves. For success, the biosphere reserve concept needs to be clearly understood and applied through landscape zoning. Designated reserves then need a management system with inclusive good governance, strong participation and collaboration, adequate finance and human resource allocation and stable and responsible management and implementation. All rather obvious but it is difficult to achieve without commitment to the biosphere reserve concept by the governance authorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. The Probabilistic Safety Analysis during low power and shutdown, framework to improve safety; El APS a baja potencia en parada, marco para la mejora de la seguridad

    Energy Technology Data Exchange (ETDEWEB)

    Nos, V.

    2014-02-01

    Historically Probabilistic Safety Analysis (PSA) has been focused exclusively at full power operation, nevertheless, operational experience has revealed that events occurred during low power and shutdown can also present threats for the safety of the plant. Through qualitative assessment (NUMARC 91-06) about the configuration in shutdown have been internationally accepted, the benefits of Low Power and Shutdown PSA have been demonstrated as fundamental framework of quantitative understanding for improving safety and risk management in the above mentioned operative conditions of the plant. (Author)

  8. Program of social protection for Chornobyl nuclear power plant staff and Slavutich town residents in the aftermath of the plant shutdown

    International Nuclear Information System (INIS)

    Komarov, V.A.

    2001-01-01

    In order to solve social issues related to ChNPP shutdown, the Ukrainian Government approved 'Program of Social Protection for Chornobyl Nuclear Power Plant Staff and Slavutich Town Residents in Aftermath of Plant Shutdown' on 29 November 2000. The Program Objective is to ensure social protection and support of well being of ChNPP staff and Slavutich town residents after the plant shutdown. Preserve and develop town infrastructure. Create compensatory jobs; efficiently manage human resources; provide social allowances and guarantees to the ChNPP staff that is being released, and Slavutich town residents

  9. Corrosion product behaviour in the Loviisa nuclear power plant primary coolant: measures taken to lower radiation levels by modified shutdown procedures

    International Nuclear Information System (INIS)

    Jaernstroem, R.T.

    1983-01-01

    The primary circuit chemistry of the Loviisa nuclear power plant differs in some respects from the concepts commonly used in PWRs. In general, Loviisa 1, which is now in its sixth cycle, and Loviisa 2, which is in its second refuelling and maintenance shutdown (October 1982), are very clean compared with several other PWRs and it seems to be possible to keep the radiation levels low and even reduce them by using correct chemistry during operation; the shutdown conditions seem to have great influence on this matter. These modified shutdown conditions and their influence on radiation levels, dose rates and radwaste buildup are discussed. (author)

  10. Estimation of reactor pool water temperature after shutdown in JRR-3M

    International Nuclear Information System (INIS)

    Yagi, Masahiro; Sato, Mitsugu; Kakefuda, Kazuhiro

    1999-01-01

    The reactor pool water temperature increasing by the decay heat was estimated by calculation. The reactor pool water temperature was calculated by increased enthalpy that was estimated by the reactor decay heat, the heat released from the reactor biological shielding concrete, reactor pool water surface, the heat conduction from the canal and the core inlet piping. These results of calculation were compared with the past measured data. As the results of estimation, after the JRR-3M shutdown, the calculated reactor pool temperature first increased sharply. This is because the decay heat was the major contribution. And then, rate of increased reactor pool temperature decreased. This is because the ratio of heat released from reactor biological shielding concrete and core inlet piping to the decay heat increased. Besides, the calculated reactor pool water temperature agreed with the past measured data in consequence of correcting the decay heat and the released heat. The corrected coefficient k 1 of decay heat was 0.74 - 0.80. And the corrected coefficient k 2 of heat released from the reactor biological shielding concrete was 3.5 - 4.5. (author)

  11. Procedure of Active Residual Heat Removal after Emergency Shutdown of High-Temperature-Gas-Cooled Reactor

    Directory of Open Access Journals (Sweden)

    Xingtuan Yang

    2014-01-01

    Full Text Available After emergency shutdown of high-temperature-gas-cooled reactor, the residual heat of the reactor core should be removed. As the natural circulation process spends too long period of time to be utilized, an active residual heat removal procedure is needed, which makes use of steam generator and start-up loop. During this procedure, the structure of steam generator may suffer cold/heat shock because of the sudden load of coolant or hot helium at the first few minutes. Transient analysis was carried out based on a one-dimensional mathematical model for steam generator and steam pipe of start-up loop to achieve safety and reliability. The results show that steam generator should be discharged and precooled; otherwise, boiling will arise and introduce a cold shock to the boiling tubes and tube sheet when coolant began to circulate prior to the helium. Additionally, in avoiding heat shock caused by the sudden load of helium, the helium circulation should be restricted to start with an extreme low flow rate; meanwhile, the coolant of steam generator (water should have flow rate as large as possible. Finally, a four-step procedure with precooling process of steam generator was recommended; sensitive study for the main parameters was conducted.

  12. Time Delay for the Initiation of an Emergency Shutdown at the Peruvian Nuclear Reactor RP-10

    International Nuclear Information System (INIS)

    Ramon, A.; Ovalle, E.; Canaza, D.; Salazar, A.; Zapata, A.; Felix, J.; Arrieta, R.; Vela, M.

    2008-01-01

    In this paper we show the measurement of the time delay for the initiation of an emergency shutdown state at the RP-10 Reactor. This time delay is the one corresponding to the delay between the detection of a signal of any fixed limit and the start of a protective action to get the reactor in a safety state. The experimental method used is based on monitoring two signals in an oscilloscope, one signal is the elected initiate event and the other is the de-energizing of electromagnets of the security bars. The time delay for each safety and control rods, was measured for seven energizing current values in a range of 36 - 52 mA. The results showed that the minimum value is (84 ± 1.26) ms and the maximum is (108 ± 1.60) ms. In all cases it is noted that, the delay time is less than the limit values prefixed down in the reactor safety report. (authors)

  13. Time Delay for the Initiation of an Emergency Shutdown at the Peruvian Nuclear Reactor RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Ramon, A.; Ovalle, E.; Canaza, D.; Salazar, A.; Zapata, A.; Felix, J.; Arrieta, R.; Vela, M. [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru)

    2008-07-01

    In this paper we show the measurement of the time delay for the initiation of an emergency shutdown state at the RP-10 Reactor. This time delay is the one corresponding to the delay between the detection of a signal of any fixed limit and the start of a protective action to get the reactor in a safety state. The experimental method used is based on monitoring two signals in an oscilloscope, one signal is the elected initiate event and the other is the de-energizing of electromagnets of the security bars. The time delay for each safety and control rods, was measured for seven energizing current values in a range of 36 - 52 mA. The results showed that the minimum value is (84 {+-} 1.26) ms and the maximum is (108 {+-} 1.60) ms. In all cases it is noted that, the delay time is less than the limit values prefixed down in the reactor safety report. (authors)

  14. Summary of Information Presented at an NRC-Sponsored Low-Power Shutdown Public Workshop, April 27, 1999, Rockville, Maryland

    International Nuclear Information System (INIS)

    Wheeler, Timothy A.; Whitehead, Donnie W.; Lois, Erasmia

    1999-01-01

    This report summarizes a public workshop that was held on April 27, 1999, in Rockville, Maryland. The workshop was conducted as part of the US Nuclear Regulatory Commission's (NRC) efforts to further develop its understanding of the risks associated with low power and shutdown operations at US nuclear power plants. A sufficient understanding of such risks is required to support decision-making for risk-informed regulation, in particular Regulatory Guide 1.174, and the development of a consensus standard. During the workshop the NRC staff discussed and requested feedback from the public (including representatives of the nuclear industry, state governments, consultants, private industry, and the media) on the risk associated with low-power and shutdown operations

  15. Human reliability analysis in low power and shut-down probabilistic safety assessment: Outcomes of an international initiative

    Directory of Open Access Journals (Sweden)

    Manna Giustino

    2012-01-01

    Full Text Available Since the beginning of the nuclear power generation, human performance has been a very important factor in all phases of the plant lifecycle: design, commissioning, operation, maintenance, surveillance, modification, and decommissioning. This aspect has been confirmed by the operating experience. A workshop was organized by the IAEA and the Joint Research Centre of the European Commission, on Harmonization of low power and shutdown probabilistic safety assessment for WWER nuclear power plants. One of the major objectives of the Workshop was to provide a comparison of the approaches and results of human reliability analyses for WWER 440 and WWER 1000, and gain insights for future application of human reliability analyses in Low Power and Shutdown scenarios. This paper provides the insights and conclusions of the workshops concerning human reliability analyses and human factors.

  16. Summary of Information Presented at an NRC-Sponsored Low-Power Shutdown Public Workshop, April 27, 1999, Rockville, Maryland

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, Timothy A.; Whitehead, Donnie W.; Lois, Erasmia

    1999-07-01

    This report summarizes a public workshop that was held on April 27, 1999, in Rockville, Maryland. The workshop was conducted as part of the US Nuclear Regulatory Commission's (NRC) efforts to further develop its understanding of the risks associated with low power and shutdown operations at US nuclear power plants. A sufficient understanding of such risks is required to support decision-making for risk-informed regulation, in particular Regulatory Guide 1.174, and the development of a consensus standard. During the workshop the NRC staff discussed and requested feedback from the public (including representatives of the nuclear industry, state governments, consultants, private industry, and the media) on the risk associated with low-power and shutdown operations.

  17. Design Report for the ½ Scale Air-Cooled RCCS Tests in the Natural convection Shutdown heat removal Test Facility (NSTF)

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, D. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Farmer, M. T. [Argonne National Lab. (ANL), Argonne, IL (United States); Lomperski, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Kilsdonk, D. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Bremer, N. [Argonne National Lab. (ANL), Argonne, IL (United States); Aeschlimann, R. W. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-06-01

    The Natural convection Shutdown heat removal Test Facility (NSTF) is a large scale thermal hydraulics test facility that has been built at Argonne National Laboratory (ANL). The facility was constructed in order to carry out highly instrumented experiments that can be used to validate the performance of passive safety systems for advanced reactor designs. The facility has principally been designed for testing of Reactor Cavity Cooling System (RCCS) concepts that rely on natural convection cooling for either air or water-based systems. Standing 25-m in height, the facility is able to supply up to 220 kW at 21 kW/m2 to accurately simulate the heat fluxes at the walls of a reactor pressure vessel. A suite of nearly 400 data acquisition channels, including a sophisticated fiber optic system for high density temperature measurements, guides test operations and provides data to support scaling analysis and modeling efforts. Measurements of system mass flow rate, air and surface temperatures, heat flux, humidity, and pressure differentials, among others; are part of this total generated data set. The following report provides an introduction to the top level-objectives of the program related to passively safe decay heat removal, a detailed description of the engineering specifications, design features, and dimensions of the test facility at Argonne. Specifications of the sensors and their placement on the test facility will be provided, along with a complete channel listing of the data acquisition system.

  18. When should fractional flow reserve be performed to assess the significance of borderline coronary artery lesions: Derivation of a simplified scoring system.

    Science.gov (United States)

    Matar, Fadi A; Falasiri, Shayan; Glover, Charles B; Khaliq, Asma; Leung, Calvin C; Mroue, Jad; Ebra, George

    2016-11-01

    To derive a simplified scoring system (SSS) that can assist in selecting patients who would benefit from the application of fractional flow reserve (FFR). Angiographers base decisions to perform FFR on their interpretation of % diameter stenosis (DS), which is subject to variability. Recent studies have shown that the amount of myocardium at jeopardy is an important factor in determining the degree of hemodynamic compromise. We conducted a retrospective multivariable analysis to identify independent predictors of hemodynamic compromise in 289 patients with 317 coronary vessels undergoing FFR. A SSS was derived using the odds ratios as a weighted factor. The receiver operator characteristics curve was used to identify the optimal cutoff (≥3) to discern a functionally significant lesion (FFR≤0.8). Male gender, left anterior descending artery apical wrap, disease proximal to lesion, minimal lumen diameter and % DS predicted abnormal FFR (≤0.8) and lesion location in the left circumflex predicted a normal FFR. Using a cutoff score of ≥3 on the SSS, a specificity of 90.4% (95% CI: 83.0-95.3) and a sensitivity of 38.0% (95% CI: 31.5-44.9) was generated with a positive predictive value of 89.0% (95% CI: 80.7%-94.6%) and negative predictive value of 41.6% (95% CI: 35.1%-48.3%). The decision to use FFR should be based not only on the % DS but also the size of the myocardial mass jeopardized. A score of ≥3 on the SSS should prompt further investigation with a pressure wire. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Østergaard, Jacob; Togeby, Mikael

    2011-01-01

    Relying on generation side alone is deemed insufficient to fulfill the system balancing needs for future Danish power system, where a 50% wind penetration is outlined by the government for year 2025. This paper investigates using the electricity demand as frequency controlled reserve (DFR) as a new...... balancing measure, which has a high potential and can provide many advantages. Firstly, the background of the research is reviewed, including conventional power system reserves and the electricity demand side potentials. Subsequently, the control logics and corresponding design considerations for the DFR...

  20. PUMA code simulation of recovery power transients after a short shutdown of the Embalse nuclear power plant

    International Nuclear Information System (INIS)

    Villar, Javier; Pomerantz, Marcelo E.

    2003-01-01

    A simulation of recovery power transients after a short shutdown on Embalse nuclear power plant equilibrium core with slightly enriched uranium fuel was performed in order to know the response of the reactor under such conditions. Also, comparison against the same event in a natural uranium core were done. No significant restrictions were found in operating with enriched fuel in the conditions of the analyzed event and in fact, slightly differences arose with natural uranium fuels. (author)

  1. Firefighter safety for PV systems: Overview of future requirements and protection systems

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Sera, Dezso; Blaabjerg, Frede

    2013-01-01

    for operators during maintenance or fire-fighting. One of the solutions is individual module shutdown by short-circuiting or disconnecting each PV module from the PV string. However, currently no standards have been adopted either for implementing or testing these methods, or doing an evaluation of the module...... shutdown procedures. This paper gives an overview on the most recent fire - and firefighter safety requirements for PV systems, with focus on system and module shutdown systems. Several solutions are presented, analyzed and compared by considering a number of essential characteristics, including...... their transient behavior, components' voltage stress and conduction losses....

  2. Demand as frequency controlled reserve

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Togeby, M.; OEstergaard, J.

    2008-09-15

    Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

  3. Shutdown dose rates at ITER equatorial ports considering radiation cross-talk from torus cryopump lower port

    Energy Technology Data Exchange (ETDEWEB)

    Juárez, Rafael, E-mail: rjuarez@ind.uned.es [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain); Pampin, Raul [F4E, Torres Diagonal Litoral B3, Josep Pla 2, Barcelona 08019 (Spain); Levesy, Bruno [ITER Organization, 13115 Route de Vinon sur Verdon, St Paul Lez Durance (France); Moro, Fabio [ENEA, Via Enrico Fermi 45, Frascati, Rome (Italy); Suarez, Alejandro [ITER Organization, 13115 Route de Vinon sur Verdon, St Paul Lez Durance (France); Sanz, Javier [Departamento de Ingeniería Energética, ETSII-UNED, Calle Juan del Rosal 12, Madrid 28040 (Spain)

    2015-11-15

    Shutdown dose rates for planned maintenance purposes is an active research field in ITER. In this work the radiation (neutron and gamma) cross-talk between ports in the most conservative case foreseen in ITER is investigated: the presence of a torus cryopump lower port, mostly empty for pumping efficiency reasons. There will be six of those ports: #4, #6, #10, #12, #16 and #18. The equatorial ports placed above them will receive a significant amount of additional radiation affecting the shutdown dose rates during in situ maintenance activities inside the cryostat, and particularly in the port interspace area. In this study a general situation to all the equatorial ports placed above torus cryopump lower ports is considered: a generic diagnostics equatorial port placed above the torus cryopump lower port (LP#4). In terms of shutdown dose rates at equatorial port interspace after 10{sup 6} s of cooling time, 405 μSv/h has been obtained, of which 160 μSv/h (40%) are exclusively due to radiation cross-talk from a torus cryopump lower port. Equatorial port activation due to only “local neutrons” contributes 166 μSv/h at port interspace, showing that radiation cross-talk from such a lower port is a phenomenon comparable in magnitude to the neutron leakage though the equatorial port plug.

  4. 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.

  5. Demand Response Spinning Reserve Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H.; Nelson-Hoffman, Janine; Torres, Carlos; Hirth,Scott; Yinger, Bob; Kueck, John; Kirby, Brendan; Bernier, Clark; Wright,Roger; Barat, A.; Watson, David S.

    2007-05-01

    The Demand Response Spinning Reserve project is a pioneeringdemonstration of how existing utility load-management assets can providean important electricity system reliability resource known as spinningreserve. Using aggregated demand-side resources to provide spinningreserve will give grid operators at the California Independent SystemOperator (CAISO) and Southern California Edison (SCE) a powerful, newtool to improve system reliability, prevent rolling blackouts, and lowersystem operating costs.

  6. 40 CFR 63.4967 - What are the requirements for continuous parameter monitoring system installation, operation, and...

    Science.gov (United States)

    2010-07-01

    ... device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect...) Automatic shutdown system. Use an automatic shutdown system in which the coating operation is stopped when...

  7. 40 CFR 63.4768 - What are the requirements for continuous parameter monitoring system installation, operation, and...

    Science.gov (United States)

    2010-07-01

    ... device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect...) Automatic shutdown system. Use an automatic shutdown system in which the coating operation is stopped when...

  8. COGNITIVE RESERVE IN AGING

    Science.gov (United States)

    Tucker, Adrienne M.; Stern, Yaakov

    2011-01-01

    Cognitive reserve explains why those with higher IQ, education, occupational attainment, or participation in leisure activities evidence less severe clinical or cognitive changes in the presence of age-related or Alzheimer’s disease pathology. Specifically, the cognitive reserve hypothesis is that individual differences in how tasks are processed provide reserve against brain pathology. Cognitive reserve may allow for more flexible strategy usage, an ability thought to be captured by executive functions tasks. Additionally, cognitive reserve allows individuals greater neural efficiency, greater neural capacity, and the ability for compensation via the recruitment of additional brain regions. Taking cognitive reserve into account may allow for earlier detection and better characterization of age-related cognitive changes and Alzheimer’s disease. Importantly, cognitive reserve is not fixed but continues to evolve across the lifespan. Thus, even late-stage interventions hold promise to boost cognitive reserve and thus reduce the prevalence of Alzheimer’s disease and other age-related problems. PMID:21222591

  9. HYDROCARBONS RESERVES IN VENEZUELA

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Cruz, D.J.

    2007-07-01

    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  10. A Geographical Information System Based Approach for Integrated Strategies of Tick Surveillance and Control in the Peri-Urban Natural Reserve of Monte Pellegrino (Palermo, Southern Italy).

    Science.gov (United States)

    Torina, Alessandra; Blanda, Valeria; Blanda, Marcellocalogero; Auteri, Michelangelo; La Russa, Francesco; Scimeca, Salvatore; D'Agostino, Rosalia; Disclafani, Rosaria; Villari, Sara; Currò, Vittoria; Caracappa, Santo

    2018-02-27

    Ticks (Acari: Ixodidae) are bloodsucking arthropods involved in pathogen transmission in animals and humans. Tick activity depends on various ecological factors such as vegetation, hosts, and temperature. The aim of this study was to analyse the spatial/temporal distribution of ticks in six sites within a peri-urban area of Palermo (Natural Reserve of Monte Pellegrino) and correlate it with field data using Geographical Information System (GIS) data. A total of 3092 ticks were gathered via dragging method from June 2012 to May 2014. The species collected were: Ixodes ventalloi (46.09%), Hyalomma lusitanicum (19.99%), Rhipicephalus sanguineus (17.34%), Rhipicephalus pusillus (16.11%), Haemaphisalis sulcata (0.36%), Dermacentor marginatus (0.10%), and Rhipicephalus turanicus (0.03%). GIS analysis revealed environmental characteristics of each site, and abundance of each tick species was analysed in relation to time (monthly trend) and space (site-specific abundance). A relevant presence of I. ventalloi in site 2 and H. lusitanicum in site 5 was observed, suggesting the possible exposure of animals and humans to tick-borne pathogens. Our study shows the importance of surveillance of ticks in peri-urban areas and the useful implementation of GIS analysis in vector ecology; studies on temporal and spatial distribution of ticks correlated to GIS-based ecological analysis represent an integrated strategy for decision support in public health.

  11. Site Characterization Report ORGDP Diffusion Facilities Permanent Shutdown K-700 Power House and K-27 Switch Yard/Switch House

    Energy Technology Data Exchange (ETDEWEB)

    Thomas R.J., Blanchard R.D.

    1988-06-13

    The K-700 Power House area, initially built to supply power to the K-25 gaseous diffusion plant was shutdown and disassembled in the 1960s. This shutdown was initiated by TVA supplying economical power to the diffusion plant complex. As a result of world wide over production of enriched, reactor grade U{sup 235}, the K-27 switch yard and switch house area was placed in standby in 1985. Subsequently, as the future production requirements decreased, the cost of production increased and the separation technologies for other processes improved, the facility was permanently shutdown in December, 1987. This Site Characterization Report is a part of the FY-88 engineering Feasibility Study for placing ORGDP Gaseous Diffusion Process facilities in 'Permanent Shutdown'. It is sponsored by the Department of Energy through Virgil Lowery of Headquarters--Enrichment and through Don Cox of ORO--Enrichment Operations. The primary purpose of these building or site characterization reports is to document, quantify, and map the following potential problems: Asbestos; PCB containing fluids; Oils, coolants, and chemicals; and External contamination. With the documented quantification of the concerns (problems) the Engineering Feasibility Study will then proceed with examining the potential solutions. For this study, permanent shutdown is defined as the securing and/or conditioning of each facility to provide 20 years of safe service with minimal expenditures and, where feasible, also serving DOE's needs for long-term warehousing or other such low-risk use. The K-700 power house series of buildings were either masonry construction or a mix of masonry and wood. The power generating equipment was removed and sold as salvage in the mid 1960s but the buildings and auxiliary equipment were left intact. The nine ancillary buildings in the power house area use early in the Manhattan Project for special research projects, were left intact minus the original special equipment

  12. Combined effects of global warming and an Atlantic meridional overturning circulation shutdown on West African and European climate

    Science.gov (United States)

    Brown, M. G.; Vizy, E. K.; Cook, K. H.

    2011-12-01

    We investigate the effects of an Atlantic meridional overturning circulation (AMOC) shutdown, for example, due to an influx of fresh water from Arctic ice sheet melting, in combination with global warming (Intergovernmental Panel on Climate Change's A2 business as normal emissions scenario) on West African and European climate. Shutdown of the AMOC by the end of this century is generally seen as possible but not likely, but Arctic ice is melting more quickly than predicted by global models, and the consequences for climate may be severe and the changes abrupt. A regional climate model with 90-km grid spacing is used to conduct a series of present day and future AMOC shutdown simulations. The present-day control initial surface and lateral boundary conditions are derived from the present day National Center for Environmental Prediction reanalysis 2 (NCEP2). For the future runs we use coupled atmosphere-ocean GCM anomalies generated from the Intergovernmental Panel on Climate Change's Assessment Report 4 (IPCC AR4) A2 business as normal emission scenario experiment and apply them directly to the present day control boundary conditions. An idealized SSTA is derived and applied to the present day SSTs based upon coupled atmosphere/ocean GCM water hosing experiments that force a shutdown of the AMOC, but placed in the context of under global warming, In both the boreal spring and summer months, cooling in the eastern Atlantic due to the AMOC shutdown causes an eastward extension of the North Atlantic subtropical high over Europe and rainfall rates decrease markedly throughout most of Europe. In May and June, rainfall rates decrease by 50-80% over Sahelian Africa as a secondary response to the eastern Atlantic cool SSTs, as dry air is advected southward, associated with enhanced northerly flow. In contrast, the atmospheric response to the SSTA in the North Atlantic over Europe and West Africa is decoupled during the boreal summer months; rainfall over Europe continues to

  13. Ovarian reserve parameters

    DEFF Research Database (Denmark)

    Bentzen, J G; Forman, Julie Lyng; Pinborg, Anja

    2012-01-01

    2-5 of the menstrual cycle or during withdrawal bleeding, blood sampling and transvaginal sonography was performed. After adjusting for age, ovarian reserve parameters were lower among users than among non-users of hormonal contraception: serum AMH concentration by 29.8% (95% CI 19.9 to 38...... was observed between duration of hormonal-contraception use and ovarian reserve parameters. No dose-response relation was found between the dose of ethinyloestradiol and AMH or AFC. This study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, AMH...... concentration and AFC may not retain their accuracy as predictors of ovarian reserve in women using hormonal contraception. Serum anti-Müllerian hormone (AMH) concentration is an indirect marker of the number of small follicles in the ovary and thereby the ovarian reserve. The AMH concentration is now widely...

  14. Interpretations of de-orbit, deactivation, and shutdown guidelines applicable to GEO satellites

    Science.gov (United States)

    Honda, L.; Perkins, J.; Sun, Sheng

    As the population of space debris in orbit around the Earth grows, the probability for catastrophic collisions increases. Many agencies such as the IADC, FCC, and UN have proposed space debris mitigation guidelines or recommendations. For example, a minimum increase in perigee altitude of 235km + (1000 Cr A / m) where Cr is the solar radiation pressure coefficient, A/m is the aspect area to dry mass ratio, and 235 km is the sum of the upper altitude of the geostationary orbit (GEO) protected region (200 km) and the maximum descent of a re-orbited spacecraft due to lunar-solar & geopotential perturbations (35 km) with an eccentricity less than or equal to 0.003. While this particular recommendation is reasonably straightforward, the assumptions an operator chooses may change the result by 25 km. Other recommendations are more ambiguous. For example, once the space vehicle has been de-orbited to the required altitude, all on-board stored energy sources must be discharged by venting propellants and pressurants, discharging batteries and disabling the ability to charge them, and performing other appropriate measures. “ Vented” is not usually defined. In addition, the broadcasting capability of the spacecraft must be disabled. Boeing and its customers are working together to devise de-orbit and deactivation sequences that meet the spirit of the recommendations. This paper derives and proposes a generic minimum deorbit altitude, appropriate depletion and venting pressures based on tank design, propellant and pressurant type, and an acceptable shutdown procedure and final configuration that avoid interference with those still in the GEO belt well into the future. The goal of this paper is to open a dialogue with the global community to establish reasonable guidelines that are straightforward, safe, and achievable before an absolute requirement is set.

  15. Plant Operation Station for HTR-PM Low Power and Shutdown operation Probabilistic safety analysis

    International Nuclear Information System (INIS)

    Liu Tao; Tong Jiejuan

    2014-01-01

    Full range Probabilistic safety analysis (PSA) is one of key conditions for nuclear power plant (NPP) licensing according to the requirement of nuclear safety regulatory authority. High Temperature Gas Cooled Reactor Pebble-bed Module (HTR-PM) has developed construction design and prepared for the charging license application. So after the normal power operation PSA submitted for review, the Low power and Shutdown operation Probabilistic safety analysis (LSPSA) also begin. The results of LSPSA will together with prior normal power PSA results to demonstrate the safety level of HTR-PM NPP Plant Operation Station (POS) is one of important terms in LSPSA. The definition of POS lays the foundation for LSPSA modeling. POS provides initial and boundary conditions for the following event tree and fault tree model development. The aim of this paper is to describe the state-of-the-art of POS definition for HTR-PM LSPSA. As for the first attempt to the high temperature gas cooled reactor module plant, the methodology and procedure of POS definition refers to the LWR LSPSA guidance, and adds to plant initial status analysis due to the HTR-PM characteristics. A specific set of POS grouping vectors is investigate and suggested for HTR-PM NPP, which reflects the characteristics of plant modularization and on-line refueling. As a result, seven POSs are given according to the grouping vectors at the end of the paper. They will be used to the LSPSA modelling and adjusted if necessary. The papers ’work may provide reference to the analogous NPP LSPSA. (author)

  16. Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit 1. Volume 5: Analysis of core damage frequency from seismic events during mid-loop operations

    Energy Technology Data Exchange (ETDEWEB)

    Budnitz, R.J. [Future Resources Associates, Inc., Berkeley, CA (United States); Davis, P.R. [PRD Consulting (United States); Ravindra, M.K.; Tong, W.H. [EQE International, Inc., Irvine, CA (United States)

    1994-08-01

    In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1) and the other at Sandia National Laboratories studying a boiling water reactor (Grand Gulf). Both the Brookhaven and Sandia projects have examined only accidents initiated by internal plant faults--so-called ``internal initiators.`` This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling shutdown conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. This report covers the seismic analysis at Surry Unit 1. All of the many systems modeling assumptions, component non-seismic failure rates, and human error rates that were used in the internal-initiator study at Surry have been adopted here, so that the results of the two studies can be as comparable as possible. Both the Brookhaven study and this study examine only two shutdown plant operating states (POSs) during refueling outages at Surry, called POS 6 and POS 10, which represent mid-loop operation before and after refueling, respectively. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POSs 6 and 10. The results of the analysis are that the core-damage frequency of earthquake-initiated accidents during refueling outages in POS 6 and POS 10 is found to be low in absolute terms, less than 10{sup {minus}6}/year.

  17. Evaluation of potential severe accidents during low power and shutdown operations at Surry, Unit 1. Volume 5: Analysis of core damage frequency from seismic events during mid-loop operations

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Davis, P.R.; Ravindra, M.K.; Tong, W.H.

    1994-08-01

    In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1) and the other at Sandia National Laboratories studying a boiling water reactor (Grand Gulf). Both the Brookhaven and Sandia projects have examined only accidents initiated by internal plant faults--so-called ''internal initiators.'' This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling shutdown conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. This report covers the seismic analysis at Surry Unit 1. All of the many systems modeling assumptions, component non-seismic failure rates, and human error rates that were used in the internal-initiator study at Surry have been adopted here, so that the results of the two studies can be as comparable as possible. Both the Brookhaven study and this study examine only two shutdown plant operating states (POSs) during refueling outages at Surry, called POS 6 and POS 10, which represent mid-loop operation before and after refueling, respectively. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POSs 6 and 10. The results of the analysis are that the core-damage frequency of earthquake-initiated accidents during refueling outages in POS 6 and POS 10 is found to be low in absolute terms, less than 10 -6 /year

  18. Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Volume 5: Analysis of core damage frequency from seismic events for plant operational state 5 during a refueling outage

    Energy Technology Data Exchange (ETDEWEB)

    Budnitz, R.J. [Future Resources Associates, Inc., Berkeley, CA (United States); Davis, P.R. [PRD Consulting (United States); Ravindra, M.K.; Tong, W.H. [EQE International, Inc., Irvine, CA (United States)

    1994-08-01

    In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Sandia National Laboratories studying a boiling water reactor (Grand Gulf), and the other at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1). Both the Sandia and Brookhaven projects have examined only accidents initiated by internal plant faults---so-called ``internal initiators.`` This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling outage conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. This report covers the seismic analysis at Grand Gulf. All of the many systems modeling assumptions, component non-seismic failure rates, and human effort rates that were used in the internal-initiator study at Grand Gulf have been adopted here, so that the results of the study can be as comparable as possible. Both the Sandia study and this study examine only one shutdown plant operating state (POS) at Grand Gulf, namely POS 5 representing cold shutdown during a refueling outage. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POS 5. The results of the analysis are that the core-damage frequency for earthquake-initiated accidents during refueling outages in POS 5 is found to be quite low in absolute terms, less than 10{sup {minus}7}/year.

  19. Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Volume 5: Analysis of core damage frequency from seismic events for plant operational state 5 during a refueling outage

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Davis, P.R.; Ravindra, M.K.; Tong, W.H.

    1994-08-01

    In 1989 the US Nuclear Regulatory Commission (NRC) initiated an extensive program to examine carefully the potential risks during low-power and shutdown operations. The program included two parallel projects, one at Sandia National Laboratories studying a boiling water reactor (Grand Gulf), and the other at Brookhaven National Laboratory studying a pressurized water reactor (Surry Unit 1). Both the Sandia and Brookhaven projects have examined only accidents initiated by internal plant faults---so-called ''internal initiators.'' This project, which has explored the likelihood of seismic-initiated core damage accidents during refueling outage conditions, is complementary to the internal-initiator analyses at Brookhaven and Sandia. This report covers the seismic analysis at Grand Gulf. All of the many systems modeling assumptions, component non-seismic failure rates, and human effort rates that were used in the internal-initiator study at Grand Gulf have been adopted here, so that the results of the study can be as comparable as possible. Both the Sandia study and this study examine only one shutdown plant operating state (POS) at Grand Gulf, namely POS 5 representing cold shutdown during a refueling outage. This analysis has been limited to work analogous to a level-1 seismic PRA, in which estimates have been developed for the core-damage frequency from seismic events during POS 5. The results of the analysis are that the core-damage frequency for earthquake-initiated accidents during refueling outages in POS 5 is found to be quite low in absolute terms, less than 10 -7 /year

  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. Handbook on loss reserving

    CERN Document Server

    Schmidt, Klaus; Schnaus, Anja

    2016-01-01

    This handbook presents the basic aspects of actuarial loss reserving. Besides the traditional methods, it also includes a description of more recent ones and a discussion of certain problems occurring in actuarial practice, like inflation, scarce data, large claims, slow loss development, the use of market statistics, the need for simulation techniques and the task of calculating best estimates and ranges of future losses. In property and casualty insurance the provisions for payment obligations from losses that have occurred but have not yet been settled usually constitute the largest item on the liabilities side of an insurer's balance sheet. For this reason, the determination and evaluation of these loss reserves is of considerable economic importance for every property and casualty insurer. Actuarial students, academics as well as practicing actuaries will benefit from this overview of the most important actuarial methods of loss reserving by developing an understanding of the underlying stochastic models...

  2. Lithium reserves and resources

    International Nuclear Information System (INIS)

    Evans, R.K.

    1978-01-01

    As a result of accelerating research efforts in the fields of secondary batteries and thermonuclear power generation, concern has been expressed in certain quarters regarding the availability, in sufficient quantities, of lithium. As part of a recent study by the National Research Council on behalf of the Energy Research and Development Administration, a subpanel was formed to consider the outlook for lithium. Principal areas of concern were reserves, resources and the 'surplus' available for energy applications after allowing for the growth in current lithium applications. Reserves and resources were categorized into four classes ranging from fully proved reserves to resources which are probably dependent upon the marketing of co-products to become economically attractive. Because of the proprietary nature of data on beneficiation and processing recoveries, the tonnages of available lithium are expressed in terms of plant feed. However, highly conservative assumptions have been made concerning mining recoveries and these go a considerable way to accounting for total losses. Western World reserves and resources of all classes are estimated at 10.6 million tonnes Li of which 3.5 million tonnes Li are located in the United States. Current United States capacity, virtually equivalent to Western World capacity, is 4700 tonnes Li and production in 1976 approximated to 3500 tonnes Li. Production for current applications is expected to grow to approx. 10,000 tonnes in year 2000 and 13,000 tonnes a decade later. The massive excess of reserves and resources over that necessary to support conventional requirements has limited the amount of justifiable exploration expenditures; on the last occasion, there was a a major increase in demand (by the USAEA) reserves and capacity were increased rapidly. There are no foreseeable reasons why this shouldn't happen again when the need is clear. (author)

  3. Generic event trees and the treatment of dependencies and non-proceduralized actions in a low power and shutdown Probabilistic Risk Assessment

    International Nuclear Information System (INIS)

    Forester, J.; Yakle, J.; Whitehead, D.; Darby, J.

    1993-01-01

    Sandia National Laboratories was tasked by the US Nuclear Regulatory Commission to perform a Probabilistic Risk Assessment (PRA) of a boiling water reactor (BWR) during low power and shutdown (LP ampersand S) conditions. The plant chosen for the study was Grand Gulf Nuclear Station (GGNS), a BWR 6. In performing the analysis, it was found that in comparison with full-power PRAs, the low decay heat levels present during LP ampersand S conditions result in a relatively large number of ways by which cooling can be provided to the core. In addition, because of the less stringent requirements imposed on system configurations possible is large and the availability of plant systems is more difficult to specify. These aspects of the LP ampersand S environment led to the development and use of ''generic'' event trees in performing the analysis. The use of ''generic'' event trees, in turn, had a significant impact on the nature of the human reliability analysis (HRA) that was performed. This paper describes the development of the event trees for the LP ampersand S PRA and important aspects of the resulting HRA

  4. Spinning Reserve From Responsive Loads

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, B.J.

    2003-04-08

    Responsive load is the most underutilized reliability resource available to the power system today. It is currently not used at all to provide spinning reserve. Historically there were good reasons for this, but recent technological advances in communications and controls have provided new capabilities and eliminated many of the old obstacles. North American Electric Reliability Council (NERC), Federal Energy Regulatory Commission (FERC), Northeast Power Coordinating Council (NPCC), New York State Reliability Council (NYSRC), and New York Independent System Operator (NYISO) rules are beginning to recognize these changes and are starting to encourage responsive load provision of reliability services. The Carrier ComfortChoice responsive thermostats provide an example of these technological advances. This is a technology aimed at reducing summer peak demand through central control of residential and small commercial air-conditioning loads. It is being utilized by Long Island Power Authority (LIPA), Consolidated Edison (ConEd), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E). The technology is capable of delivering even greater response in the faster spinning reserve time frame (while still providing peak reduction). Analysis of demand reduction testing results from LIPA during the summer of 2002 provides evidence to back up this claim. It also demonstrates that loads are different from generators and that the conventional wisdom, which advocates for starting with large loads as better ancillary service providers, is flawed. The tempting approach of incrementally adapting ancillary service requirements, which were established when generators were the only available resources, will not work. While it is easier for most generators to provide replacement power and non-spinning reserve (the slower response services) than it is to supply spinning reserve (the fastest service), the opposite is true for many loads. Also, there is more financial

  5. SUIKERBOSRAND NATURE RESERVE

    African Journals Online (AJOL)

    Suikerbosrand Nature Reserve and fts educational facilities are run by the Transvaal. Division of. Nature Conservation. ... tion and the education facilities provided. The former are utilized mainly by the general public ... artist Paul Bosman (already reviewed in the EEASA newsletter). The co-founders of the Foundation are.

  6. Session 7: Reserve

    International Nuclear Information System (INIS)

    Bailey, R.; Crockford, G.

    2001-01-01

    The reserve session was devoted to some issues that came up through the workshop, which were grouped into three main areas: The Global Accelerator Network, Problems of stress and how to get organized to minimize them, What should an operations group be responsible for? This paper summarizes the discussions that took place. (author)

  7. School Shootings Stun Reservation

    Science.gov (United States)

    Borja, Rhea R.; Cavanagh, Sean

    2005-01-01

    This article deals with the impact brought by the school shootings at Red Lake Indian Reservation in Minnesota to the school community. A deeply troubled 16-year-old student shot and killed seven other people and himself at a high school. The nation's deadliest school attack since the 1999 slayings at Colorado's suburban Columbine High School took…

  8. SUIKERBOSRAND NATURE RESERVE

    African Journals Online (AJOL)

    reserve, the total length being 66 km with six overnight huts. There are also the BokmakiePie. Nature Troil. and the Cheetah Interpretive Troil. which can be used by day visitors. The former has two loops, one of 10 km and another of 17 km. The. Cheetah Troil. is much shorter and various points of interest are interpreted en ...

  9. Calculation analysis of the radiation characteristics of the Ch NPP Unit 1 reactor structures after the final shutdown

    International Nuclear Information System (INIS)

    Burlakov, E.V.; Bylkin, B.K.; Garin, E.V.; Davydova, G.B.; Zverkov, Yu.A.; Krayushkin, A.V.; Neretin, Yu.A.; Nosovskij, A.V.; Sejda, V.A.; Skripov, A.E.; Tushev, D.V.

    2000-01-01

    The article deals with the ways of assessing RBMK structures radiation parameters, which can in future serve as a basis for work on the tasks related to planning and actual decommissioning of Power Units with RBMK reactors. It gives the main results of the calculation analysis of the radiation characteristics of the elements of the Ch NPP Unit 1 reactor structures at the final Unit shutdown stage. The article also gives a forecast of their changes as the time passes, up to 150 years of the reactor cooling. The article describes the methodology and the results of the analysis carried out. 8 refs., 3 tab., 4 figs

  10. Revisiting the analysis of passive plasma shutdown during an ex-vessel loss of coolant accident in ITER blanket

    International Nuclear Information System (INIS)

    Rivas, J.C.; Dies, J.; Fajarnés, X.

    2015-01-01

    Highlights: • We have repeated the safety analysis for the hypothesis of passive plasma shutdown for beryllium evaporation during an ex-vessel LOCA of ITER first wall, with AINA code. • We have performed a sensitivity analysis over some key parameters that represents uncertainties in physics and engineering, to identify cliff edge effects. • The obtained results for the 500 MW inductive scenario, with an ex-vessel LOCA affecting a third of first wall surface are similar to those of previous studies and point to the possibility of a passive plasma shutdown during this safety case, before a serious damage is inflicted to the ITER wall. • The sensitivity analysis revealed a new scenario potentially damaging for the first wall if we increase fusion power and time delay for impurity transport, and decrease fraction of affected first wall area and initial beryllium fraction in plasma. • After studying the 700 MW inductive scenario, with an ex-vessel LOCA affecting 10% of first wall surface, with 0.5% of Be in plasma and a time delay twice the energy confinement time, it was found that affected area of first wall would melt before a passive plasma shutdown occurs. - Abstract: In this contribution, the analysis of passive safety during an ex-vessel loss of coolant accident (LOCA) in the first wall/shield blanket of ITER has been studied with AINA safety code. In the past, this case has been studied using robust safety arguments, based on simple 0D models for plasma balance equations and 1D models for wall heat transfer. The conclusion was that, after first wall heating up due to the loss of all coolant, the beryllium evaporation in the wall surface would induce a growing impurity flux into core plasma that finally would end in a passive shut down of the discharge. The analysis of plasma-wall transients in this work is based in results from AINA code simulations. AINA (Analyses of IN vessel Accidents) code is a safety code developed at Fusion Energy Engineering

  11. 40 CFR 63.4168 - What are the requirements for continuous parameter monitoring system installation, operation, and...

    Science.gov (United States)

    2010-07-01

    ... divert the emissions away from the add-on control device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key... the monitor will indicate valve position. (iv) Automatic shutdown system. Use an automatic shutdown...

  12. Phytoplankton Biomass Distribution and Identification of Productive Habitats Within the Galapagos Marine Reserve by MODIS, a Surface Acquisition System, and In-Situ Measurements

    Science.gov (United States)

    The Galapagos Marine Reserve (GMR) is one of the most diverse ecosystems in the world. Phytoplankton are the base of the ecosystem food chain for many higher trophic organisms, so identifying phytoplankton biomass distribution is the first step in understanding the dynamic envir...

  13. Should the United States Marine Corps Refine Its System of Active Component Enlisted Recruitment in Order to Target the Needs of Select Marine Corps Reserve Units?

    Science.gov (United States)

    2012-03-23

    on its investment by not establishing a connection between the AC recruiting missions and the needs of the proximal reserve units. By establishing this...which encourages the continuum of service. The end result of this transition is an opportunity to better meet the needs of the AC and the RC, while

  14. The Strategic Petroleum Reserve

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The Strategic Petroleum Reserve program was set into motion by the 1975 Energy Policy and Conservation Act (EPCA). By 1990, 590 million barrels of oil had been placed in storage. Salt domes along the Gulf Coast offered ideal storage. Both sweet'' and sour'' crude oil have been acquired using various purchase options. Drawdown, sale, and distribution of the oil would proceed according to guidelines set by EPCA in the event of a severe energy supply disruption. (SM)

  15. [Hypertrophy and coronary reserve].

    Science.gov (United States)

    Motz, W; Scheler, S

    2008-12-01

    Left ventricular hypertrophy represents the structural mechanism of adaptation of the left ventricle as the answer of a chronic pressure overload in arterial hypertension. Initially an increment in left ventricular wall thickness occurs. In this stadium of "concentric hypertrophy" LV systolic wall stress, LV ejection fraction and myocardial oxygen consumption per weight unit myocardium remain unchanged. In the further time course of disease LV dilatation will be present. In this phase of "excentric hypertrophy" LV systolic wall stress and myocardial oxygen consumption per weight unit myocardium rise and LV ejection fraction decreases. Patients with arterial hypertension frequently complain of angina pectoris. Angina pectoris and the positive exercise tolerance test or the positive myocardial scintigraphy are the consequence of the impaired coronary flow reserve. The coronary flow reserve is diminished due to structural and functional changes of the coronary circulation. ACE-inhibitors and AT1-receptor blockers cause a significant improvement of coronary flow reserve and regression of both left ventricular hypertrophy and myocardial fibrosis.

  16. Facing the nuclear power phaseout - Swedish experiences of enterprise shutdown and organisational development

    International Nuclear Information System (INIS)

    Lundqvist, K.

    1998-02-01

    The aim of this study is to make an overview of problems and experiences connected to decommissioning and organisational changes of Swedish enterprises and public agencies from a safety perspective. The central point is the view of decommissioning of nuclear power plants as a process of change. In practice decommissioning includes both downsizing and organisational development. The question is which problems can arise and which strategy of change is most adequate from the standpoint of safety. The report starts with a summary of the most important experiences of the process of decommissioning of enterprises during the sixties to eighties concerning the consequences for the individuals and the labour market. After that follows the main results from earlier investigations of shut-down of nuclear power plants regarding the staff. The restructuring and downsizing of the public sector during the nineties have given rise to a large amount of material on staffing issues. The knowledge and experiences drawn from the organisational change processes of Swedish working life during the nineties are then summarised. At last some conclusions for decommissioning of nuclear power plants are discussed. The period before and after the termination of power generation is connected with great strain. The vulnerability of the staff increases and the faith in management can easily be destroyed, which can affect safety and the decommissioning work. The feeling of security increases if the staff continuously is kept informed and within certain limits can influence the course of events. A learning strategy is preferable in comparison to an expert oriented strategy because it is impossible to gain complete control over the technically and socially complex process of decommissioning. Instead of detailed and central planning of the process it will be safer to work in a participative way and to include all the staff in the preparations from the very beginning. By a learning way of working is

  17. Electrospun Nanofibers for Sandwiched Polyimide/Poly (vinylidene fluoride)/Polyimide Separators with the Thermal Shutdown Function

    International Nuclear Information System (INIS)

    Wu, Dezhi; Shi, Chuan; Huang, Shaohua; Qiu, Xiaochun; Wang, Huan; Zhan, Zhan; Zhang, Peng; Zhao, Jinbao; Sun, Daoheng; Lin, Liwei

    2015-01-01

    Nanofibers fabricated by the electrospinning process have been used to construct sandwich-type Polyimide/Poly (vinylidene fluoride)/Polyimide (PI/PVDF/PI) separators with the thermal shutdown function for lithium ion batteries. This architecture uses the good thermal stability of PI as the top and bottom structure layers. Under high temperature operations, the middle layer made of PVDF nanofibers can melt and form a pore-free film to shut down the battery operation. The electrolyte uptake and ionic conductivity of the PI/PVDF/PI separator are superior to those of commercial polyolefin separators at 476% and 3.46 mS cm −1 , respectively, resulting better battery performances in terms of impedance, discharge capacity and cycle life. Under high temperature treatments above 170 °C, the self-shutdown function of the PI/PVDF/PI has been observed within 10 minutes, which could serve as the safety mechanism to defend the thermal runaway issue of lithium ion batteries. The effects of heating temperature and different time on the morphologies of each layer and electrolyte uptake of the separator are characterized as well

  18. Fractional Reserve Banking

    OpenAIRE

    Andreasen, Niels; Bjerregaard, Mads; Lund, Jonas; Olsen, Ove Bitsch; Rasmussen, Andreas Dalgas

    2012-01-01

    Projektet er bygget op omkring kritisk realisme, som er det gennemgående videnskabelige fundament til undersøgelsen af hvilke strukturelle grunde der er til finansiel ustabilitet i Danmark. Projektet går i dybden med Fractional Reserve Banking og incitamentsstrukturen i banksystemet. Vi bevæger os både på det makro- og mikroøkonomiske niveau i analysen. På makro niveau bruger vi den østrigske skole om konjunktur teori (The Positive Theory of the Cycle). På mikro niveau arbejder vi med princip...

  19. Reserve evaluation of minerals at NUCLEBRAS

    International Nuclear Information System (INIS)

    Marques, J.P.M.; Guerra, P.A.G.; Vinha, C.A.G. da

    1980-10-01

    The method used for the reserve evaluation of minerals, particularly of uranium, as used worldwide, and specially at NUCLEBRAS is described. This is done through a series of procedures envolving basic definitions, reserve evaluation methods (conventional, statistical and geoestatistical), data management, use of computer systems, classification and evaluation of reserves. (Author) [pt

  20. Human Reliability Analysis. Applicability of the HRA-concept in maintenance shutdown; Analys av maensklig tillfoerlitlighet. HRA-begreppets tillaempbarhet vid revisionsavstaellning

    Energy Technology Data Exchange (ETDEWEB)

    Obenius, Aino (MTO Psykologi AB, Stockholm (SE))

    2007-08-15

    Probabilistic Safety Analysis (PSA) is performed for Swedish nuclear power plants in order to make predictions and improvements of system safety. The analysis of the Three Mile Island and Chernobyl accidents contributed to broaden the approach to nuclear power plant safety. A system perspective focusing on the interaction between aspects of Man, Technology and Organization (MTO) emerged in addition to the development of Human Factors knowledge. To take the human influence on the technical system into consideration when performing PSAs, a Human Reliability Analysis (HRA) is performed. PSA is performed for different stages and plant operating states, and the current state of Swedish analyses is Low power and Shutdown (LPSD), also called Shutdown PSA (SPSA). The purpose of this master's thesis is to describe methods and basic models used when analysing human reliability for the LPSD state. The following questions are at issue: 1. How can the LPSD state be characterised and defined? 2. What is important to take into consideration when performing a LPSD HRA? 3. How can human behaviour be modelled for a LPSD risk analysis? 4. According to available empirical material, how are the questions above treated in performed analysis of human operation during LPSD? 5. How does the result of the questions above affect the way methods for analysis of LPSD could and/or should be developed? The procedure of this project has mainly consisted of literature studies of available theory for modelling of human behaviour and risk analysis of the LPSD state. This study regards analysis of planned outages when maintenance, fuel change, tests and inspections are performed. The outage period is characterised by planned maintenance activities performed in rotating 3-shifts, around the clock, as well as many of the persons performing work tasks on the plant being external contractors. The working conditions are characterised by stress due to heat, radiation and physically demanding or

  1. 76 FR 64250 - Reserve Requirements of Depository Institutions: Reserves Simplification and Private Sector...

    Science.gov (United States)

    2011-10-18

    ... D; Docket No. R-1433] RIN No. 7100 AD 83 Reserve Requirements of Depository Institutions: Reserves Simplification and Private Sector Adjustment Factor AGENCY: Board of Governors of the Federal Reserve System... public comment on proposed amendments to Regulation D, Reserve Requirements of Depository Institutions...

  2. 48 CFR 4.501 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false [Reserved] 4.501 Section 4.501 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Electronic Commerce in Contracting 4.501 [Reserved...

  3. Are uranium reserves adequate?

    International Nuclear Information System (INIS)

    Anon.

    2006-01-01

    Against a backdrop of growing concerns about global warming and geopolitical pressures on fossil energies, especially natural gas and oil, interest in nuclear power has revived considerably. Conscious of its addiction to oil and reeling from a series of gigantic blackouts, the United States, in the words of its president, must 'aggressively move forward with the construction of nuclear power plants'. Some European countries have approved new power plant construction (Finland and France), while the more reserved ones (Belgium, Germany and Sweden) have begun to show a change in attitude. Asia, meanwhile, is host to the planet's largest number of potential nuclear construction projects in this first half of the 21. century. All these signs point to a sharp rise in uranium consumption, the basic fuel for these plants. But are there enough resources to support a nuclear revival on a planetary scale? The publication of the Red Book on uranium in late May 2006 was an opportunity for Thierry Dujardin, Deputy Director of Science and Development at the OECD's Nuclear Energy Agency, to take stock of resources. He gives his opinion in this paper

  4. Internet-based reservation system (Internet-based control of timers for building technical services) - Final report; Internetbasiertes Reservationssystem (Internetbasierte Einstellung von Zeitsteuerungen haustechnischer Anlagen) - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Huber, A.; Woodtli, M.

    2008-07-01

    A common measure to save energy in buildings is the adjustment of the operating time of the building service facilities to the busy time of the building (i.e. lowering period). For lack of better resources, the general lowering periods in irregularly occupied buildings often are reduced to a minimum or the adjustment of the operating time is completely missing. In order to adjust the operating time optimally to the actual busy time, an internet-based booking system has been developed, which allows users to register a room assignment online. This booking system is linked with the building service facilities. This ensure the optimal setting of the lowering periods and therefore allows saving energy. The technical implementation resulted from a programmable logic controller (PLC) that can be accessed via a web browser. Temperature offset boxes have been added as interface between the PLC and the existing facilities in order that the system is applicable in existing buildings too. The booking system has been installed in two test objects and has also been successfully tested with the responsible staff (caretaker, real estate management). The booking system may be contemplated online: http://www.hetag.ch. (author)

  5. An analysis of operational experience during low power and shutdown and a plan for addressing human reliability assessment issues

    International Nuclear Information System (INIS)

    Barriere, M.; Luckas, W.; Whitehead, D.; Ramey-Smith, A.

    1994-06-01

    Recent nuclear power plant events (e.g. Chernobyl, Diablo Canyon, and Vogtle) and US Nuclear Regulatory Commission (NRC) reports (e.g. NUREG-1449) have led to concerns regarding human reliability during low power and shutdown (LP ampersand S) conditions and limitations of human reliability analysis (HRA) methodologies in adequately representing the LP ampersand S environment. As a result of these concerns, the NRC initiated two parallel research projects to assess the influence of LP ampersand S conditions on human reliability through an analysis of operational experience at pressurized water reactors (PWRs) an boiling water reactors (BWRs). These research projects, performed by Brookhaven National Laboratory for PWRS, and Sandia National Laboratories for BWRs, identified unique aspects of human performance during LP ampersand S conditions and provided a program plan for research and development necessary to improve existing HRA methodologies. This report documents the results of the analysis of LP ampersand S operating experience and describes the improved HRA program plan

  6. Summary report of already published guidance on L2 PSA for external hazards, shutdown states, spent fuel storage

    International Nuclear Information System (INIS)

    Dirksen, Gerben; Sauvage, Estelle

    2014-01-01

    This report (deliverable D40.2 of the project ASAMPSA-E) proposes a review of the existing guidance with relevance to ASAMPSA-E PSA Level 2 topics (external hazards, shutdown states, spent fuel pool). As a complement of this task, the deliverable D40.2 tries to identify any potential missing guidance for the development of an extended PSA level 2, and any sources of knowledge beyond existing guidance which might help generating extended PSA level 2. Based on this approach the last section provides a summary compilation which identifies possibilities for completing existing guidelines (especially the guidance developed in the previous ASAMPSA2 project) and/or creating new guidelines for extended PSA Level 2. (authors)

  7. The application of knowledge management and TRIZ for solving the safe shutdown capability of fire alarms in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chia-Nan; Chen, Hsin-Po; Hsueh, Ming-Hsien; Chin, Fong-Li [National Kaohsiung Univ. of Applied Sciences, Kaohsiung City, Taiwan (China). Dept. of Industrial Engineering and Management

    2017-11-15

    The Fukushima nuclear disaster in 2011 has raised widespread concern over the safety of nuclear power plants. This study employed knowledge management in conjunction with the Teoriya Resheniya Izobreatatelskih Zadatch (TRIZ) method in the formulation of a database to facilitate the evaluation of post-fire safe shutdown capability with the aim of safeguarding nuclear facilities in the event of fire. The proposed approach is meant to bring facilities in line with US Nuclear Regulatory Commission (NRC) standards. When implemented in a case study of an Asian nuclear power plant, our method proved highly effective in the detection of 22 cables that fell short of regulatory requirements, thereby reducing 850,000 paths to 0. This study could serve as reference for industry and academia in the development of systematic approaches to the upgrading of nuclear power plants.

  8. Modeling long-term risk to environmental and human systems at the Hanford Nuclear Reservation: Scope and findings from the initial model

    International Nuclear Information System (INIS)

    Scott, Michael J.; Brandt, Charles A.; Bunn, Amoret L.; Engel, David W.; Eslinger, Paul W.; Miley, Terri B.; Napier, Bruce A.; Prendergast-Kennedy, Ellen L.; Nieves, Leslie A.

    2005-01-01

    The Groundwater/Vadose Zone (GW/VZ) Integration Project at the U.S. Department of Energy's Hanford Site in Washington state is currently developing the tools and supporting data to assess the cumulative impact to human and ecological health and the region's economy and cultures from waste that will remain at the Hanford Site after the site closes. This integrated system of new and legacy models and data is known as the System Assessment Capability (SAC). The environmental transport modules of the SAC modeling system provide estimates of contaminant concentrations from Hanford Site sources in a time-dependent manner in the vadose zone, groundwater, and the Columbia River and its associated sediments. The Risk/Impact Module uses these estimates of media- and time-specific concentrations to estimate potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and the cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in environmental transport on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show successful linking of codes and very small long-term risks for the 10 radionuclides and chemicals evaluated

  9. Observations and insights from the Grand Gulf Low Power and Shutdown Study of POS 5 during a refueling outage

    International Nuclear Information System (INIS)

    Whitehead, D.W.

    1998-01-01

    With the completion of the documentation of the results from the Grand Gulf Nuclear Power Plant Low Power and Shutdown (LP and S) Project funded by the US Nuclear Regulatory Commission, detailed probabilistic risk assessment (PRA) information from a boiling water reactor for a specific time period in LP and S conditions became available for examination. This paper summarizes why LP and S conditions should be examined and how the particular operational state was selected. It also summarizes observations and insights extracted from an examination of: (1) results in the LP and S documentation, (2) the specific models and assumptions used in the LP and S analyses, (3) selected results from the full power analysis, (4) the experience of the analysts who performed the original LP and S study, and (5) results from sensitivity calculations to help determine the impact that model assumptions and data values had on the results from the original LP and S analysis. Observations and insights on core damage frequency and aggregate risk (early fatalities and total latent cancer fatalities) associated with operations during plant operational state 5 (i.e., basically cold shutdown as defined by Technical Specifications) during a refueling outage for traditional internal events are provided. In addition, a discussion of similarities and differences between full power accidents and accidents during LP and S conditions is provided. As part of this discussion, core damage frequency and risks results are presented on a per hour and per calendar year basis, allowing alternative perspectives on both the core damage frequency and risk associated with these two operational states

  10. Defence-in-depth strategy of fire protection and its relevance after final shutdown (by the example of Germany)

    Energy Technology Data Exchange (ETDEWEB)

    Beesen, Michael; Ernst, Benjamin; Fischer, Guenter [TUeV SUeD Industrie Service GmbH (Germany)

    2015-12-15

    Nuclear power plants (NPP) are protected against internal and external fires by a fire protection defence-in-depth concept including the following precautionary measures: operational, structural and equipment related fire protection measures as well as manual fire fighting. The fire protection measures are designed in consideration of fires to be expected (from fire loads permanently and temporarily present together with potential ignition sources) in order to prevent a violation of both the protection goals of public law and the nuclear protection goals / radiological safety objectives in case of internal and external fires. The aspect ''What is the future significance of the fire protection defence-in-depth concept?'' needs to be considered with regard to the situation following the final shutdown. From our point of view as a TSO (technical safety organization) both the non-nuclear protection goals (e.g. prevent occurrence of a fire; ensure escape and rescue of humans) as well as the nuclear ones have to be ensured after final shutdown of a nuclear plant. The protection goals of public law will almost completely remain after the plant has stopped commercial operation while the nuclear safety objectives will be stepwise reduced in consideration of the decommissioning status until the end of the nuclear supervision. Nevertheless, the fire protection concept must clearly specify those fire protection measures that are necessary to ensure the plants' safety. The situation on site regularly needs to be under examination to check if the fire protection concept covers all conditions to be considered and if the existing fire protection measures are sufficient or if an adaption is necessary.

  11. Diagnostic Performance of a Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography System With Low-Dose Technetium-99m as Assessed by Fractional Flow Reserve.

    Science.gov (United States)

    Chikamori, Taishiro; Hida, Satoshi; Tanaka, Nobuhiro; Igarashi, Yuko; Yamashita, Jun; Shiba, Chie; Murata, Naotaka; Hoshino, Kou; Hokama, Yohei; Yamashina, Akira

    2016-04-25

    Although stress single-photon emission computed tomography (SPECT) using a cadmium-zinc-telluride (CZT) camera facilitates radiation dose reduction, only a few studies have evaluated its diagnostic accuracy in Japanese patients by applying fractional flow reserve (FFR) measurements. We prospectively evaluated 102 consecutive patients with suspected or known coronary artery disease with a low-dose stress/rest protocol ((99m)Tc radiotracer 185/370 MBq) using CZT SPECT. Within 3 months, coronary angiography was performed and a significant stenosis was defined as ≥90% diameter narrowing on visual estimation, or as a lesion of <90% and ≥ 50% stenosis with FFR ≤0.80. To detect individual coronary stenosis, the respective sensitivity, specificity, and accuracy were 86%, 75%, and 82% for left anterior descending artery stenosis, 76%, 81%, and 79% for left circumflex artery stenosis, and 87%, 92%, and 90% for right coronary artery stenosis. When limited to 92 intermediate stenotic lesions in which FFR was measured, stress SPECT showed 77% sensitivity, 91% specificity, and 84% accuracy, whereas the diagnostic value decreased to 52% sensitivity, 68% specificity, and 58% accuracy based only on visual estimation of ≥75% diameter narrowing. CZT SPECT demonstrated a good diagnostic yield in detecting hemodynamically significant coronary stenoses as assessed by FFR, even when using a low-dose (99m)Tc protocol with an effective dose ≤5 mSv. (Circ J 2016; 80: 1217-1224).

  12. Elevated pulmonary arterial and systemic plasma aldosterone levels associate with impaired cardiac reserve capacity during exercise in left ventricular systolic heart failure patients: A pilot study.

    Science.gov (United States)

    Maron, Bradley A; Stephens, Thomas E; Farrell, Laurie A; Oldham, William M; Loscalzo, Joseph; Leopold, Jane A; Lewis, Gregory D

    2016-03-01

    Elevated levels of aldosterone are a modifiable contributor to clinical worsening in heart failure with reduced ejection fraction (HFrEF). Endothelin-1 (ET-1), which is increased in HFrEF, induces pulmonary endothelial aldosterone synthesis in vitro. However, whether transpulmonary aldosterone release occurs in humans or aldosterone relates to functional capacity in HFrEF is not known. Therefore, we aimed to characterize ET-1 and transpulmonary aldosterone levels in HFrEF and determine if aldosterone levels relate to peak volume of oxygen uptake (pVO2). Data from 42 consecutive HFrEF patients and 18 controls referred for invasive cardiopulmonary exercise testing were analyzed retrospectively. Radial ET-1 levels (median [interquartile range]) were higher in HFrEF patients compared with controls (17.5 [11.5-31.4] vs 11.5 [4.4-19.0] pg/ml, p = 0.04). A significant ET-1 transpulmonary gradient (pulmonary arterial [PA] - radial arterial levels) was present in HFrEF (p reserve capacity in HFrEF. Published by Elsevier Inc.

  13. Cardiovascular involvement and manifestations of systemic Chikungunya virus infection: A systematic review [version 2; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    María Fernanda Alvarez

    2017-05-01

    Full Text Available Background: In the last three years, chikungunya virus disease has been spreading, affecting particularly the Americas, producing more than two million cases. In this setting, not only new disease-related epidemiological patterns have been found, but also new clinical findings have been reported by different research groups. These include findings on the cardiovascular system, including clinical, electrocardiographic and echocardiographic alterations. No previous systemic reviews have been found in major databases about it. Methods: We performed a systematic review looking for reports about cardiovascular compromise during chikungunya disease. Cardiac compromise is not so common in isolated episodes; but countries where chikungunya virus is an epidemic should be well informed about this condition. We used 6 bibliographical databases as resources: Medline/Pubmed, Embase, ScienceDirect, ClinicalKey, Ovid and SciELO. Dengue reports on cardiovascular compromise were included as well, to compare both arbovirus’ organic compromises. Articles that delved mainly into the rheumatic articular and cutaneous complications were not considered, as they were not in line with the purpose of this study. The type of articles included were reviews, meta-analyses, case-controls, cohort studies, case reports and case series. This systematic review does not reach or performed a meta-analysis. Results: Originally based on 737 articles, our reviewed selected 40 articles with 54.2% at least mentioning CHIKV cardiovascular compromise within the systemic compromise. Cardiovascular manifestations can be considered common and have been reported in France, India, Sri Lanka, Malaysia, Colombia, Venezuela and USA, including mainly, but no limited to: hypotension, shock and circulatory collapse, Raynaud phenomenon, arrhythmias, murmurs, myocarditis, dilated cardiomyopathy, congestive insufficiency, heart failure and altered function profile (Troponins, CPK. Conclusions

  14. 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.

  15. Inverse Modeling of the Natural State of the Geysers Valley Hydrothermal System (kronotsky Nature Reserve, Kamchatka) Preceding of the Giant Landslide

    Science.gov (United States)

    Kiryukhin, A. V.

    2011-12-01

    On June 3, 2007, a catastrophic Giant landslide took place in the Geysers Valley, Kamchatka. It occurred synchronously with a steam explosion and was then transformed into a debris mudflow. Within a few minutes, 20 mln m3 of rocks were shifted 2 km downstream the Geysernaya river, which created a dam with Podprudnoe lake behind, and buried more than 23 geysers. The 20-30 m deep Podprudnoe lake started to inject cold water into the remaining part of the Geysers Valley hydrothermal system. The objectives of the present study are to integrate available hydrogeological data to develop 3D thermal hydrodynamic (chemical) models to deduce a mechanism for the formation hydrothermal system and its response to changing recharge/discharge conditions after the Giant landslide of June 3, 2007, and to understand triggers of such catastrophic events to be able to forecast future ones. TOUGH2-EOS3 software was used. EOS3 (equation of state 3) module is capable of describing two-phase (liquid+gas) two-component (water+air) unsaturated zone conditions prevalent in the elevated parts of the Geysers Valley. Modeling runs were completed in order to explore the possible timing of the Geysers Valley formation. Modeling different scenarios shows, that the formation of Geysers Valley hydrothermal system took from 20,000 to 30,000 years in terms of temperature distributions and discharge flowrates, and meteoric recharge took place on the outcrops of Mt. Geysernaya rhyolite extrusion on the right bank of Geysernaya river. Model analysis shows wide high pressure two-phase zone at a depth of 150-250 m between steam vent, backing Giant landslide of June 3, 2007 and geyser Velikan, which are conditions of potential steam explosion, if steam pressure transmits to shallower levels. Inverse modeling capabilities of iTOUGH2-EOS3 were used to estimate upflow rate, reservoir permeability and productivity indexes of 39 most significant hot springs based on their flowrates data. Model parameters are

  16. A eukaryotic-acquired gene by a biotrophic phytopathogen allows prolonged survival on the host by counteracting the shut-down of plant photosynthesis

    KAUST Repository

    Garavaglia, Betiana S.

    2010-01-28

    Xanthomonas citri pv. citri, the bacteria responsible for citrus canker posses a biological active plant natriuretic peptide (PNP)-like protein, not present in any other bacteria. PNPs are a class of extracellular, systemically mobile peptides that elicit a number of plant responses important in homeostasis and growth. Previously, we showed that a Xanthomonas citri pv. citri mutant lacking the PNP-like protein XacPNP produced more necrotic lesions in citrus leaves than wild type infections and suggested a role for XacPNP in the regulation of host homeostasis. Here we have analyzed the proteome modifications observed in citrus leaves infected with the wild type and XacPNP deletion mutant bacteria. While both of them cause downregulation of enzymes related to photosynthesis as well as chloroplastic ribosomal proteins, proteins related to defense responses are up-regulated. However, leaves infiltrated with the XacPNP deletion mutant show a more pronounced decrease in photosynthetic proteins while no reduction in defense related proteins as compared to the wild-type pathogen. This suggests that XacPNP serves the pathogen to maintain host photosynthetic efficiency during pathogenesis. The results from the proteomics analyses are consistent with our chlorophyll fluorescence data and transcript analyses of defense genes that show a more marked reduction in photosynthesis in the mutant but no difference in the induction of genes diagnostic for biotic-stress responses. We therefore conclude that XacPNP counteracts the shut-down of host photosynthesis during infection and in that way maintains the tissue in better conditions, suggesting that the pathogen has adapted a host gene to modify its natural host and render it a better reservoir for prolonged bacterial survival and thus for further colonization. 2010 Garavaglia et al.

  17. Cardiovascular involvement and manifestations of systemic Chikungunya virus infection: A systematic review [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    María Fernanda Alvarez

    2017-03-01

    Full Text Available Background: In the last three years, chikungunya virus disease has been spreading, affecting particularly the Americas, producing more than two million cases. In this setting, not only new disease-related epidemiological patterns have been found, but also new clinical findings have been reported by different research groups. These include findings on the cardiovascular system, including clinical, electrocardiographic and echocardiographic alterations. Methods: We performed a systematic review looking for reports about cardiovascular compromise during chikungunya disease. Cardiac compromise is not so common in isolated episodes; but countries where chikungunya virus is an epidemic should be well informed about this condition. We used 6 bibliographical databases as resources: Medline/Pubmed, Embase, ScienceDirect, ClinicalKey, Ovid and SciELO. Dengue reports on cardiovascular affectation were included as well, to compare both arbovirus’ organic affectations. Articles that delved mainly into the rheumatic articular and cutaneous complications were not considered, as they were not in line with the purpose of this study. The type of articles included were reviews, meta-analyses, case-controls, cohort studies, case reports and case series. Results: Originally based on 737 articles, our reviewed selected 40 articles with 54.2% at least mentioning CHIKV cardiovascular compromise within the systemic affectation. Cardiovascular manifestations can be considered common and have been reported in France, India, Sri Lanka, Malaysia, Colombia, Venezuela and USA, including mainly, but no limited to: hypotension, shock and circulatory collapse, Raynaud phenomenon, arrhythmias, murmurs, myocarditis, dilated cardiomyopathy, congestive insufficiency, heart failure and altered function profile (Troponins, CPK. Conclusions: Physicians should be encouraged to keep divulgating reports on the cardiovascular involvement of chikungunya virus disease, to raise awareness

  18. A PRA case study of extended long term decay heat removal for shutdown risk assessment

    International Nuclear Information System (INIS)

    Roglans, J.; Ragland, W.A.; Hill, D.J.

    1992-01-01

    A Probabilistic Risk Assessment (PRA) of the Experimental Breeder Reactor II (EBR-II), a Department of Energy (DOE) Category A research reactor, has recently been completed at Argonne National Laboratory (ANL). The results of this PRA have shown that the decay heat removal system for EBR-II is extremely robust and reliable. In addition, the methodology used demonstrates how the actions of other systems not normally used for actions of other systems not normally used for decay heat removal can be used to expand the mission time of the decay heat removal system and further increase its reliability. The methodology may also be extended to account for the impact of non-safety systems in enhancing the reliability of other dedicated safety systems

  19. 12 CFR 614.4710 - [Reserved

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false [Reserved] 614.4710 Section 614.4710 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4710 [Reserved] ...

  20. Unsteady-Flow Modeling for Emergency Shutdown of the CAP Canal

    OpenAIRE

    Clemmens, Bert; Wahlin, Brian; Shapiro, Marcus; Dent, Patrick

    2016-01-01

    The Central Arizona Project (CAP) is designed to bring about 1.9 ML of Colorado River water per year to Maricopa, Pima, and Pinal counties in Arizona. CAP carries water from the Colorado River at Lake Havasu toTucson. The CAP canal system is a 540 km long system of conveyance system aqueducts, tunnels, pumping plants,pipelines and a large reservoir (just north of Phoenix, AZ). Water is pumped uphill from the Colorado River. This study was conducted for the Hayden-Rhodes Aqueduct of the Centra...

  1. Seismic monitoring system replacement at Temelin plant

    International Nuclear Information System (INIS)

    Baltus, R.; Palusamy, S.S.

    1996-01-01

    The VVER-1000 plants under construction at Temelin (Czech Republic) were designed with an automatic reactor trip system triggered on seismic peak accelerations. Within the plant I and C upgrade, Westinghouse designed a digital Seismic Monitoring System to be integrated in an Artificial Intelligence based Diagnostic and Monitoring System. The system meets the requirements of the emerging standards prepared by the US NRC on the basis of EPRI studies, which recommend a detailed data evaluation and a pre-shutdown plant inspection before orderly shutdown, if required, rather than immediate emergency shutdown. The paper presents the arguments about automatic trip, as discussed in an IAEA meeting attended by expert consultants from Japan, Russia, US and Eastern and Western Europe. It describes the system installed at Temelin, including the plant specific criteria for OBE exceedance. Finally it presents the capabilities and limitations of the integration into an overall Diagnostic and Monitoring System

  2. Computerized reserves assessment improves colliery planning. [Poland

    Energy Technology Data Exchange (ETDEWEB)

    Pozor, L.; Wrobel, R.

    1984-01-01

    The authors describe systems developed in Poland for the computerised assessment of coal reserves. The Zasoby system calculates coal reserves and evaluates selected natural properties of seams within the boundaries of an arbitrary mining property, based entirely on exploratory borehole data. The IOS-10 system is based on the Polish data bank for bituminous coal deposits. It is not suitable for use in mine design procedures, but is widely used for the statistical recording of reserves in areas currently being worked. The major part of the paper is devoted to a description of the Geo-3 system, used for the computation of reserves in prospective areas from borehole data, as well as in active mining areas or partially worked-out deposits. The computation method is explained and examples of the results obtained are given.

  3. 48 CFR 9904.404-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.404-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.404-10 [Reserved] ...

  4. 48 CFR 9904.401-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.401-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.401-10 [Reserved] ...

  5. 48 CFR 9904.400 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.400 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.400 [Reserved] ...

  6. 48 CFR 9904.402-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.402-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.402-10 [Reserved] ...

  7. 48 CFR 9904.405-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.405-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.405-10 [Reserved] ...

  8. 48 CFR 9904.407-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.407-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.407-10 [Reserved] ...

  9. 48 CFR 9904.408-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.408-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.408-10 [Reserved] ...

  10. 48 CFR 9904.406-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.406-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.406-10 [Reserved] ...

  11. 48 CFR 9904.403-10 - [Reserved

    Science.gov (United States)

    2010-10-01

    ... Section 9904.403-10 Federal Acquisition Regulations System COST ACCOUNTING STANDARDS BOARD, OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.403-10 [Reserved] ...

  12. CMS RPC commissioning of the existing detector during the long shutdown

    Science.gov (United States)

    Cimmino, A.; Ban, Y.; Cai, J.; Li, Q.; Liu, S.; Qian, S.; Wang, D.; Xu, Z.; Zhang, F.; Choi, Y.; Kim, D.; Goh, J.; Choi, S.; Hong, B.; Kang, J. W.; Kang, M.; Kwon, J. H.; Lee, K. S.; Lee, S. K.; Park, S. K.; Pant, L. M.; Mohanty, A. K.; Chudasama, R.; Singh, J. B.; Bhatnagar, V.; Mehta, A.; Kumar, R.; Cauwenbergh, S.; Costantini, S.; Crucy, S.; Fagot, A.; Garcia, G.; Ocampo, A.; Poyraz, D.; Salva, S.; Thyssen, F.; Tytgat, M.; Zaganidis, N.; Doninck, W. V.; Cabrera, A.; Chaparro, L.; Gomez, J. P.; Gomez, B.; Sanabria, J. C.; Avila, C.; Ahmad, A.; Muhammad, S.; Shoaib, M.; Hoorani, H.; Awan, I.; Ali, I.; Ahmed, W.; Asghar, M. I.; Shahzad, H.; Sayed, A.; Ibrahim, A.; Aly, S.; Assran, Y.; Radi, A.; Elkafrawy, T.; Sharma, A.; Colafranceschi, S.; Abbrescia, M.; Calabria, C.; Colaleo, A.; Iaselli, G.; Loddo, F.; Maggi, M.; Nuzzo, S.; Pugliese, G.; Radogna, R.; Venditti, R.; Verwilligen, P.; Benussi, L.; Bianco, S.; Piccolo, D.; Paolucci, P.; Buontempo, S.; Cavallo, N.; Merola, M.; Fabozzi, F.; Iorio, O. M.; Braghieri, A.; Montagna, P.; Riccardi, C.; Salvini, P.; Vitulo, P.; Vai, I.; Magnani, A.; Dimitrov, A.; Litov, L.; Pavlov, B.; Petkov, P.; Aleksandrov, A.; Genchev, V.; Iaydjiev, P.; Rodozov, M.; Sultanov, G.; Vutova, M.; Stoykova, S.; Hadjiiska, R.; Ibargüen, H. S.; Morales, M. I. P.; Bernardino, S. C.; Bagaturia, I.; Tsamalaidze, Z.; Crotty, I.; Kim, M. S.

    2014-10-01

    February 1 th 2013 marked the end of the first period of running of the Large Hadron Collider (LHC) and the start of a two-year break from operation (LS1) aimed at consolidating both the accelerator as well as the detectors. By the end of LS1, the LHC is expected to provide collisions at 13 Tev. While, by 2020, the ultimate instantaneous luminosity is expected to be 1034/cm2/s. To prepare for this scenario, the Resistive Plate Chamber system at the CMS experiment is planning several detector maintainance and consolidation interventions. These include High Voltage and Low Voltage system reparations, gas leak identification and reparation, signal channel connectivity and functionality. Commissioning and upgrade plans for the existing CMS RPC system are presented here.

  13. Demand for International Reserves in Turkey

    Directory of Open Access Journals (Sweden)

    Yimaz Sinem

    2014-06-01

    Full Text Available Having an important place in the international monetary system, international reserves held by central bank usually reflect country’s economic strength in terms of international finance and trade. There are many reasons for holding international reserves by central banks such as financing the deficit in the balance of payment, managing the monetary and exchange rate policies, minimizing the negative effects of external shocks and reducing the cost of borrowing. Continuously changing and diversifying characteristics of these reasons affect the demand for reserves depending to the economic conditions of the country. Over the last ten years, there has been a tremendous increase in international reserves held by Turkish Central Bank. From 2002 to 2012, the reserves of the bank have risen from 20 billion dollars to 96 billion dollars, showing an increase more than four times. This sudden and huge increase in the foreign reserves drove us to determine and investigate the factors which induce the Turkish Central Bank to hold high level of reserves. Thus, the purpose of this study is to estimate and analyze the demand for international reserves held by central banks using the buffer stock model in the case of Turkey. The data used in the study is monthly and cover the period of 1990:03-2012:10. The buffer stock model was econometrically estimated by using the OLS method for three different models. Our findings indicate that the opportunity cost affected reserve demand much stronger than the reserve volatility in Turkish case.

  14. Integrity, safety and efficiency in LNG transfer: impact of emergency shutdown and release operations

    NARCIS (Netherlands)

    Bokhorst, E. van; Driessen, F.P.G.; Nennie, E.D.; Remans, D.; Smeulers, J.P.M.

    2013-01-01

    Caused by the global increase of demand for natural gas the interest in offshore liquefaction, transport and re-gasification grows rapidly. The installations that are presently developed are in essence copies of the onshore systems that are already many years in operation. However, the fact that the

  15. CAREM-25: Residual heat removal system

    International Nuclear Information System (INIS)

    Arvia, Roberto P.; Coppari, Norberto R.; Gomez de Soler, Susana M.; Ramilo, Lucia B.

    2000-01-01

    The objective of this work was the definition and consolidation of the residual heat removal system for the CAREM 25 reactor. The function of this system is cool down the primary circuit, removing the core decay heat from hot stand-by to cold shutdown and during refueling. In addition, this system heats the primary water from the cold shutdown condition to hot stand-by condition during the reactor start up previous to criticality. The system has been designed according to the requirements of the standards: ANSI/ANS 51.1 'Nuclear safety criteria for the design of stationary PWR plants'; ANSI/ANS 58.11 'Design criteria for safe shutdown following selected design basis events in light water reactors' and ANSI/ANS 58.9 'Single failure criteria for light water reactor safety-related fluid systems'. The suggested design fulfills the required functions and design criteria standards. (author)

  16. Federal Reserve System Semiannual Regulatory Agenda

    Science.gov (United States)

    2010-04-26

    .... DATES: Comments about the form or content of the agenda may be submitted any time during the next 6... prohibit certain payments to mortgage brokers and loan officers that are based on the loan's terms and... compensation received. New rules regarding eligibility restrictions and disclosures for credit insurance and...

  17. The State Council's decision interpreting the provisions of the mining code about mine shutdowns

    International Nuclear Information System (INIS)

    Couderc, G.; Sanvee, S.

    2004-01-01

    In line with the special police powers granted by article 77 of the Mining Code, administrative authorities may issue orders to a mine operator to undertake measures for ensuring public safety and security and for reinforcing the solidity of public and private buildings. When major risks to the security of goods and persons crop up following warrants for executing such orders, administrative authorities can step in once again and either take, till the expiration of mining rights, new measures, or else order, when risks of cave-ins have been identified, an operator to set up and run the equipment necessary for supervising and preventing these risks until these duties are transferred to the state. However a decision by the State Council on 22 October 2003 formulates a reservation: if the administration has not used the procedure for definitively shutting down a mine to identify all risks and to order the operator the measures for ensuring security in line with all known risks, then the administration itself will carry the responsibility for implementing such measures. (authors)

  18. New Czechoslovak detector of leaking condenser tubes usable in both shutdown and reduced output operation of power unit

    International Nuclear Information System (INIS)

    Matal, O.; Klinga, J.; Varvarovsky, F.; Zachar, J.; Fratric, D.

    1986-01-01

    The main reason for penetration of undesirable admixtures from cooling water in the condensate is the inleakage of steam turbine condensers. Briefly assessed are the means and methods of detecting and locating condenser leaks used in the world and in power facilities in Czechoslovakia. Equipment was developed based on measuring the difference between the pressure in a temporarily closed condenser tube and ambient pressure, for leak testing of condenser tubes during operation and during shutdown of WWER-440 units. Two types of the equipment were tested in practice. Type VUEZ-PHN 85P meets the requirements of objective leak tests and those of leak location in condenser tubes and of leak detection in tube expansion in the tube plates of WWER-440 unit condensers, this as concerns sensitivity, the objectivity of results, the cost of tests, and minimal losses of power during the test. Type VUEZ-PHN 85P can be used for leak location in all tube type heat exchangers with access to tube outlets in which under- or overpressure can be achieved in the space between the tubes relative to ambient pressure during the test. (Z.M.) 5 figs., 4 tabs., 11 refs

  19. Inactivating the spindle checkpoint kinase Bub1 during embryonic development results in a global shutdown of proliferation

    Directory of Open Access Journals (Sweden)

    Taylor Stephen S

    2009-09-01

    Full Text Available Abstract Background Bub1 is a component of the spindle assembly checkpoint, a surveillance mechanism that maintains chromosome stability during M-phase. Bub1 is essential during the early stages of embryogenesis, with homozygous BUB1-null mice dying shortly after day E3.5. Bub1 is also required later during embryogenesis; inactivation of BUB1 on day E10.5 appears to rapidly block all further development. However, the mechanism(s responsible for this phenotype remain unclear. Findings Here we show that inactivating BUB1 on day E10.5 stalls embryogenesis within 48 hours. This is accompanied by a global shutdown of proliferation, widespread apoptosis and haemorrhaging. Conclusion Our results suggest that Bub1 is required throughout the developing embryo for cellular proliferation. Therefore, Bub1 has been shown to be essential in all scenarios analyzed thus far in mice: proliferation of cultured fibroblasts, spermatogenesis, oogenesis and both early and late embryonic development. This likely reflects the fact that Bub1 has dual functions during mitosis, being required for both SAC function and chromosome alignment.

  20. Shutdown channels and fitted interlocks in atomic reactors; Chaines de securite et verrouillages installes sur les piles atomiques

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J.; Landauer, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    This catalogue consists of tables (one per reactor) giving the following information: number and type of detectors, range of the shutdown channels, nature of the associated electronics, thresholds setting off the alarms, fitted interlocks. These cards have been drawn up with a view to an examination of the reactors safety by the 'Reactor Safety Sub-Commission', they take into account the latest decisions. The reactors involved in this review are: Azur, Cabri, Castor-Pollux, Cesar-Marius-2, Edf-2, EL3, EL4, Eole, G1, G2-G3, Harmonie, Isis, Masurca, Melusine, Minerve, Osiris, Pegase, Peggy, PAT, Rapsodie, SENA, Siloe, Siloette, Triton-Nereide, and Ulysse. (authors) [French] Ce catalogue est compose d'un ensemble de tableaux (a raison de un tableau par pile) donnant les renseignements suivants: nombre et nature des detecteurs, dynamique des chaines, nature de l'electronique associee, seuils provoquant des actions de securite, verrouillages installes. Ces fiches ont ete etablies en vue de l'examen de la securite des piles par la 'Sous-Commission de Surete des Piles', et tiennent compte des decisions de celle-ci. Les reacteurs concernes sont: Azur, Cabri, Cator-Pollux, Cesar-Marius-2, Edf-2, EL3, EL4, Eole, G1, G2-G3, Harmonie, Isis, Masurca, Melusine, Minerve, Osiris, Pegase, Peggy, PAT, Rapsodie, SENA, Siloe, Siloette, Triton-Nereide, et Ulysse. (auteurs)