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The Daya Bay reactor neutrino experiment

CERN Document Server

The Last Unknown Neutrino Mixing Angle $\\theta_{13}$ and the Daya Bay Experiment

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Howard A. Baldwin and Robert W. Freyman. (NASA-CR-138152) TELEMERY LINK FOR AN. 574-2179 9 ..... Baldwin, H.A., "Long Range Radio Tracking of ...

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... 15, 14, Robert Constable, Cornell University, NY, Building Interactive Digital Libraries of Formal Algorithmic Knowledge, Navy. ...

International Nuclear Information System (INIS)

From view on Organization Behavior theory, the concept, development and affecting factors of safety culture are introduced. The focuses are on the establishment, development and management practice for safety culture at Daya Bay NPP. A strong safety culture, also demonstrated, has contributed greatly to improving performance at Daya Bay

International Nuclear Information System (INIS)

The safety analysis checklist scope and the criteria of key parameters needed to be checked for Daya bay reload cycles are introduced. The INCORE code package was used for the safety evaluation of Daya bay unit 2 cycle 2. The method and the contents can not only be applicable for Daya Bay reload cycles but also for Qinshan 600 MW and Qinshan 300 MW reload cycles.

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Robert A. Martock. Cleveland State University, Cleveland, Ohio. Synthesis and Structural Characterization of a. Novel Indium Mercapto Derivative. [Clln(SCH. 2 ...

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W. Wayne Scott, Chattanooga State Technical Institute, 4501 Amnico Highway,. Chattanooga, Tennessee 3401. Robert L. Seale, University of Arizona, Tuscon, ...

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... accidentally released from a Soviet military laboratory (Meselson ... Robert Koch and Louis Pasteur worked to introduce ... species (eg, rat, mouse, dog, monkey) for ...

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... of Robert J. Braun, Jesse M. Jenson, and Daniel J. Thompson with plot establishment and field data collection. We ... ...

International Nuclear Information System (INIS)

The Daya Bay reactor neutrino experiment is located at the Daya Bay nuclear power plant in Shenzhen, China. The experiment deploys eight 'identical' antineutrino detectors to measure antineutrino fluxes from six 2.9 GWth reactor cores in three underground experimental halls at different distances. The target zone of the Daya Bay detector is filled with 20 t 0.1% Gd doped LAB liquid scintillator. The baseline uncorrelated detector uncertainty is ?0.38% using current experimental techniques. Daya Bay can reach a sensitivity of sin22?13<0.01 with baseline uncertainties after 3 years of data taking.

International Nuclear Information System (INIS)

The installation procedure, the fabrication, fitting up, positioning, adjustment and welding of piping, examinations, hydrostatics testing and insulation of piping for reactor primary circuit piping of Daya Bay Nuclear power Plant are briefly described.

International Nuclear Information System (INIS)

2002 p. 139 China Sun Haiying Ye Zhiqiang Bu Jianhua Guangdong Nuclear

International Nuclear Information System (INIS)

The Daya Bay reactor neutrino experiment is designed to study the disappearance of antineutrinos from the Daya Bay nuclear power plant in China. The goal of this experiment is to measure the remaining unknown neutrino mixing parameter ?13 with high precision: sin2(2?13)<0.01. The experiment is presently under construction and it is anticipated that data acquisition will begin in 2011.

International Nuclear Information System (INIS)

Based on the reliability analysis methods of FMEA and FTA, according to the result of ETA of PRA in Daya by NPP, the top events of the fault trees of reactor protection system and the success criteria were established. By using RISK-SPECTRUM procedure, the unavailability and the minimal cut-sets (MCS) of the fault trees were obtained. The results of analysis was put into the visual risk analysis software of Daya bay NPP as the support of data

International Nuclear Information System (INIS)

Daya Bay Nuclear Power Station is the largest joint-venture project which is also the largest commercial nuclear power plant currently under construction in China mainland. Organized and executed strictly in accordance with international standards, the Daya Bay project is seen as the first step taken by China in the development programme of large-capacity commercial nuclear power units.

International Nuclear Information System (INIS)

For the first time in China, Daya Bay Nuclear Power Station applied the advanced technology of worldwide commercial pressurized reactors to the in-core detectors, the leading excore six-chamber instrumentation for precise axial power distribution, and the related data processing. Described in this article are the neutron flux measurement in Daya Bay Nuclear Power Station, and the detailed data processing.

UK PubMed Central (United Kingdom)

Robert van Gulik was a respected Dutch sinologist and author who first translated a collection of traditional Chinese detective stories into English and then created additional fictional stories based...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Science and technology could be revolutionized by quantum computers, but building them from solid-state devices will not be easy. Robert W Keyes of IBM's research division outlines the challenges in scaling up the technology from lab experiments to practical devices. (U.K.)

UK PubMed Central (United Kingdom)

Pfister, Robert M. (Lamont Geological Observatory, Palisades, N.Y.), and Paul R. Burkholder. Numerical taxonomy of some bacteria isolated from Antarctic and tropical seawaters. J....Full Text Available

International Nuclear Information System (INIS)

Central in the paper are two results on the existence of 'economical' embeddings in a Euclidean space. The first result (Corollary 1.4) states the existence of an embedding with image intersecting the large-dimensional planes in sets of 'controllable' dimension. The second result (Corollary 1.6) proves the existence of maps such that each small-dimensional plane contains 'controllably' many points of the image. Well known results of Noebeling-Pontryagin, Roberts, Hurewicz, Boltyanskii, and Goodsell can be obtained as consequences of these results. Their infinite-dimensional version concerning an embedding in a Hilbert space is also established (Theorem 1.8).

International Nuclear Information System (INIS)

Search for the value of ?13 mixing angle is of importance in understanding the lepton flavor mixing matrix, and in motivating future experiments to probe CP violation in the lepton sector. Among the present experimental approaches, reactor experiment can provide a clean laboratory for the ?13-measurement. The Daya Bay experiment will start civil construction this year at Daya Bay, Guangdong, China. The goal of this experiment is to reach a sensitivity in sin2 2?13 of < 0.01 at 90% C.L. by precisely measuring the disappearance and spectral distortion of reactor electron anti-neutrinos with multiple identical detectors at different baselines. The talk will present the current status and prospects of the experiment.

International Nuclear Information System (INIS)

The validation of the forecast model for early emergency response to nuclear accidents is evaluated by trace tests in atmosphere in Daya Bay nuclear power site. The simulation experiment of the Daya Bay nuclear power site shows that the particle spreading image and the time-integrated concentration distribution given by plume concentration prediction model can perform the variation of pathway of the pollutant transport, as well as the effects of topography on transport and diffusion of pollutants. The simulation of five trace tests in field shows that 59.1% of ratios between predicted results and observed results are within the range of 10, and 41% of ratios are within the range of 5 approximately. (authors)

International Nuclear Information System (INIS)

The author describes feasibility study on the scheme of disposing spent guide tubes at Daya Bay nuclear power plant, including scheme selection, packing cask design, disposal operation and technological process, budget estimation and safety evaluation. The research results show that the new scheme is feasible on technology, and reasonable on budget. If the scheme is adopted to dispose the spent guide tubes at Daya Bay nuclear power station, it can not only save large funds, but also accumulate experience on disposing non-compressible low and intermediate level solid radioactive wastes produced at nuclear power station for the country

International Nuclear Information System (INIS)

Unit one of Daya Bay, China's first nuclear power plant was officially opened in February 1994. The nuclear island has been built by Framatome and is an improved version of the Gravelines 5 and 6, 900MWe Pressurized Water Reactors. Extra seismic protection has been included because of greater earthquake risk. The heat exchanger capacity has also been increased as the sea cooling water can be at 30"oC. The technical specifications and details of the fuel loading are given. The technical assistance, management and training of Chinese personnel are discussed. Two further units may be built if Daya Bay 1 is successful. (UK).

International Nuclear Information System (INIS)

Investigations were carried out of radiation level around Daya Bay for three times since the construction and operation Daya bay Nuclear Power Station and Lingao Nuclear Power Station in Guangdong province in the period of 1988 to 2000. As shown by the investigation, the radiation levels both in the field and indoors remains unchanged by and large but slightly higher than before on the roads. Also this paper gives the analysis of variations in radiation levels form site to site and from time to time. It was shown that, for environmental ? radiation levels measurements, typical measuring sites have significant impact on the meaning results. (authors)

International Nuclear Information System (INIS)

The author describes the purpose, classification and main process of acceptance test of full scope simulator of Daya Bay Nuclear Power Plant, including the correction of non-conformance items which are discovered during the performance of acceptance tests. The results of the acceptance tests show that the model accepted by the full scope simulator of Daya Bay Nuclear Power Plant is fully able to cope with the simulation of normal transients and incidental transients and the performance of the simulator indeed compiled with the technical specifications which are defined n the relevant contracts.

CERN Document Server

We study the prospects of pinning down the effects of non-standard antineutrino interactions in the source and in the detector at the Daya Bay neutrino facility. It is well known that if the non-standard interactions in the detection process are of the same type as those in the production, their net effect can be subsumed into a mere shift in the measured value of the leptonic mixing angle theta_13. Relaxing this assumption, the ratio of the antineutrino spectra measured by the Daya Bay far and near detectors is distorted in a characteristic way, and good fits based on the standard oscillation hypothesis are no longer viable. We show that, under certain conditions, three years of Daya Bay running can be sufficient to provide a clear hint of non-standard neutrino physics.

International Nuclear Information System (INIS)

Presented here is the calculation of radionuclide concentration in gaseous effluents from the Daya Bay Nuclear Power Plant by using the Gaussian model, based on the analysis of the radionuclides in gaseous effluents and based on the measured wind field in the area of Guangdong province in November 2005. The calculating results about the relative concentration distribution of the radionuclides in Guangdong province, especially in Daya Bay, Shengzheng, Zhuhai and Guangzhou, are obtained. These results can provide reference data for the effect of radiation on the environment of Guangdong province under normal conditions of operation of the Daya Bay Nuclear Power Plant. It can also provide reference data for monitoring possible nuclear incidents in nuclear power plants. (authors)

International Nuclear Information System (INIS)

Weakly penetrating radiation monitoring and investigating with area monitors and individual dosimeters were carried out at Daya Bay nuclear power plant during its refueling outages. This paper introduces monitoring methods, measuring results, data analysis and assessment, presents some suggestions for monitoring plan and protection measures in the future as well. (authors)

International Nuclear Information System (INIS)

The authors report the individual monitoring data management system (IDOSE) at Daya Bay Nuclear Power Station. The components of the individual monitoring system, the design requirements of IDOSE, the characteristics and application of this computerized management system are mainly presented. Its application shows that IDOSE meets the requirements of the concerning occupational standards of the state and matches with the requirements of IAEA/ISOE.

International Nuclear Information System (INIS)

'Small radioactive source results in big accident' have occurred repeatedly in China and worldwide alike. Radioactive source management is one of the key activities for a nuclear power plant to maintain its good safety record and image to the public. From aspects of establishing the management system, centralized storage, periodic accounting, performing whole process control to the source usage and experience feedback etc., the author reports the practice and experience of radioactive source management in Daya Bay Nuclear Power Plant

International Nuclear Information System (INIS)

Daya Bay Nuclear Power Station has made a series of tries and efforts on radiation source control and benefited from them since it was put into commercial operation. Some of them were introduced from experience feedbacks of foreign nuclear power industry and others came from our own good practices

International Nuclear Information System (INIS)

Both the accuracy and real-time are quite strictly required for the RCS thermal-hydraulic model of the simulation of nuclear power station. So, a large amount of reasonable simplifications should be carried on. The author introduces the RCS thermal-hydraulic model of the full scope simulator of Daya Bay Nuclear Power Station, and emphasizes on the fundamental hypotheses and computation method of its kernel part--DEFI programme.

International Nuclear Information System (INIS)

The fuel management study on 18-months fuel cycle project is introduced for Daya Bay Nuclear Power Station. Station from the selection of the objective of fuel management for 18-months cycle, the method used and the analysis done are explained in detail to reach the final loading pattern chosen

International Nuclear Information System (INIS)

The philosophy of work management in radiation protection puts emphasis on the following up and management of overall process from work selection, planning, preparation, implementation till experience feedback, and overall optimization of production and safety management. This paper reports practices and experiences of Daya Bay nuclear power plant in the implementation of the philosophy during operational radiation protection through the practical examples

British Library Electronic Table of Contents (United Kingdom)

We have designed a local trigger board for the Daya Bay reactor neutrino experiment, which is aimed to measure the neutrino mixing angle sin22?13 with a precision down to 1% level. The local trigger board processes both the total number of coincident photomultiplier tube (PMT) hits and the PMT energy sum to make trigger decisions. With this design, a high trigger probability is achieved to meet the system requirement. The design of the local trigger board is presented.

International Nuclear Information System (INIS)

The human causal factors for all human error licensing operational events on Daya Bay nuclear power station since 1993 to 2003 are categorized, the trend of these causal factors is analyzed. The emphasis is placed on analyzing the deficiencies on complying with and executing regulations and procedures. The results provide directional reference for nuclear power station to improve human performance. (author)

International Nuclear Information System (INIS)

The author reports briefly a noble gas leakage searching process in which a person was contaminated in Daya Bay NPP, the radionuclide causing contamination was ascertained as the daughter product of "8"8Kr, the "8"8Rb; By taking air contamination sampling and measuring the "8"8Rb concentration in the room, the leakage source was predetermined and the leakage rate of primary coolant was estimated

International Nuclear Information System (INIS)

A lot of recent experimental results show that cladding failure limits to the RCCA ejection accident will be changed because of the impact of the high irradiation on the fuel rod behavior in the reactor. The maximal assembly discharge burnup in Daya Bay unit 1 and 2 will reach up to 52 GMd/tU with 18 month fuel cycle. It is necessary to perform the specific RCCA ejection accident analysis for the high burnup fuel assembly in order to evaluate the maximal enthalpy in the fuel rods. There is no definite design limit of maximal enthalpy for high burnup assembly during the RCCA ejection accident. One could perform the rod ejection accident analysis for the high burnup assemblies and compare the analytical results with the specific experimental results. The RCCA ejection accident analysis for the high burnup assemblies for Daya Bay NPS has been performed based on the conventional methodology (2D-1D). For each anticipated cycle in ...

International Nuclear Information System (INIS)

The circulating cooling water flowrate of GNPS and LNPS is totally about 190 m"3/s. Both stations are located on the western coast of semi-closed Daya Bay. A lot of studies concerning thermal impact of GNPS and LNPS have been carried out since 1987, including mathematical model, physical model, on-site survey and satellite remote sensing, etc. This paper describes the hydrological features of Daya Bay and discharge characteristics of circulating water of GNPS and LNPS, estimates the actual thermal impact of GNPS and LNPS, and indicates that it is advantageous for the dilution of circulating water while the two discharge channels of GNPS and LNPS are combined together towards east

British Library Electronic Table of Contents (United Kingdom)

In the field of Living Probabilistic Safety Assessment (LPSA) the reliability data updating is an important factor. In risk analysis equipment failure data is needed to estimate the frequencies of events contributing to risk posed by a facility. Five years data of emergency diesel generator (EDG) of Daya Bay Nuclear Power Plant (NPP) has been studied in this paper. The data updating process has been done by using two methods, i.e., the classical method and Bayesian method. The aim of using these methods is to calculate the operational failure rate (@l) and demand failure probability (p). The results show that the operational failure rate is 1.7E-3 per hour and the demand failure probability is 2.4E-2 demand per day for Daya Bay NPP. By comparing the results obtain from classical and Bayesi...

CERN Document Server

A reactor-neutrino experiment, Daya Bay, has been proposed to determine the least-known neutrino mixing angle theta_13 using electron antineutrinos produced at the Daya Bay nuclear power complex in China. Daya Bay is an international collaboration with institutions from China, the United States, the Czech Republic, Hong Kong, Russia, and Taiwan. The experiment will use eight identical detectors deployed at three different locations optimized for monitoring the antineutrino rates from the six reactors and for detecting any rate deficit and spectral distortion near the first oscillation maximum. The overburden of the under ground experimental halls, connected with tunnels, ranges from about 250 to 900 meters-water-equivalent so that the cosmogenic background is small compared to the number of observed antineutrino events. Civil construction of tunnels and experimental facilities is planned to start in 2007, with detector ...

British Library Electronic Table of Contents (United Kingdom)

The search for the mixing angle Formula Not Shown , the last unknown angle in the neutrino mixing matrix, is one of the main priorities in the field of neutrino physics. By measuring Formula Not Shown to better than 0.01 at 90% C.L., the Daya Bay Reactor Neutrino Experiment has the highest sensitivity to this parameter among all the other experiments that are currently operating or under construction. The experiment consists of multiple identical detectors placed underground at different baselines from three groups of reactors, a configuration that minimizes systematic errors and cosmogenic backgrounds. The main aspects of the experiment, as well as its current status and future prospects, are reviewed.

CERN Document Server

The Daya Bay Reactor Neutrino Experiment is designed to determine the yet unknown neutrino mixing angle theta_13 by measuring the disappearance of electron antineutrinos from several nuclear reactor cores, using multiple underground detectors at different baselines to minimize systematic errors and to suppress the cosmogenic background. The civil construction has begun since October 2007, enabling first commissioning data in 2009, and full data taking will begin in late 2010. The planned sensitivity in sin^2 (2theta_13) of better than 0.01 at 90% CL will be achieved in three years of data-taking. I will present an overview and current status of the experiment.

International Nuclear Information System (INIS)

The author describes the Gamma -spectrum analysis results of "1"1"0"mAg, the method used, and the coincidence correction theory on which the analysis is based. The samples were placed at the upper end of the detector. The monitoring results of "1"1"0"mAg in the surrounding marine area from the beginning of operation of the Daya Bay nuclear power plant are reviewed as well. The results showed that "1"1"0"mAg traces were detected in some marine species. However, the concentrations observed are far below the National Standard limits

International Nuclear Information System (INIS)

This article discusses the Daya Bay nuclear power plant in-core flux thimble tube in-service inspection method and strategy. High light of the multiple frequency eddy current technology adopted including frequency and probe choice, standard design, data acquisition process are involved. The wear defect-growing trends are studied on base of the history data, which contribute to the in-service inspection strategy decision. (authors)

International Nuclear Information System (INIS)

This paper describes the design of PMT readout module for detector prototype of Daya Bay Reactor Neutrino Experiment. According to the design requirements of the readout module, the basic structure of the readout module is discussed. This paper also discusses how to realize the charge measurement and time measurement and data processing using a high performance FPGA. The DAQ system including three readout modules and one trigger module are well commissioned and doing data taking now. (authors)

International Nuclear Information System (INIS)

The scenario of the development of a new procedure for cutting out the broken protective wells for thermocouples inside the deep holes in the tube plate in the moisture re-heater (MSR) at Daya Bay nuclear power station is presented. Focused in the innovation and improvement of the self-made tools, the new procedure produced an effective method to cut out swing long inserts stuck inside the deep holes. (authors)

CERN Document Server

The near infrared (NIR) upgrade to the Robert Stobie Spectrograph (RSS) on the Southern African Large Telescope (SALT), RSS/NIR, extends the spectral coverage of all modes of the visible arm. The RSS/NIR is a low to medium resolution spectrograph with broadband imaging, spectropolarimetric, and Fabry-Perot imaging capabilities. The visible and NIR arms can be used simultaneously to extend spectral coverage from approximately 3200 A to 1.6 um. Both arms utilize high efficiency volume phase holographic gratings via articulating gratings and cameras. The NIR camera is designed around a 2048x2048 HAWAII-2RG detector housed in a cryogenic dewar. The Epps optical design of the camera consists of 6 spherical elements, providing sub-pixel rms image sizes of 7.5 +/- 1.0 um over all wavelengths and field angles. The exact long wavelength cutoff is yet to be determined in a detailed thermal analysis and will depend on the semi-warm instrument cooling scheme. Initial estimates ...

Energy Technology Data Exchange (ETDEWEB)

Universal Oil Products, Inc. (UOP) of Des Plaines, Illinois has contracted A.E. Roberts & Associates, Inc. (AERA) of Atlanta, Georgia to prepare a sensitivity analysis for the development of the Fluidized-bed Copper Oxide (FBCO) process. As proposed by AERA in September 1991, development of the FBCO process design for a 500 mega-watt (MW) unit was divided into three tasks: (1) Establishment of a Conceptual Design, (2) Conceptual Design, (3) Cost Analysis Task 1 determined the basis for a conceptual design for the 500 megawatt (MW) FBCO process. It was completed by AERA in September of 1992, and a report was submitted at that time {open_quotes}Establishment of the Design Basis for Application to a 500 MW Coal-fired Facility.{close_quotes} Task 2 gathered all pertinent data available to date and reviewed its applicability to the 500 MW FBCO process. Work on this task was carried out on a joint basis by the AERA team members: Roberts & ...

Energy Technology Data Exchange (ETDEWEB)

In October 1992, the US Department of Energy, Richland Field Office (RL) requested that Westinghouse Hanford Company (WHC) respond to a letter from EM-331 asking for completion of a survey of items in storage but not categorized as waste (Roberts 1992). The letter contained an attachment with instructions on how to fill out the attached form and what to exclude from the survey (Appendix A). This report is a summary of the information from the response issued to RL. This report primarily is for use in estimating future waste volumes that may have been overlooked because of the nature of their classification as material not categorized as waste (MNCAW) (i.e., not yet declared Waste).

CERN Document Server

In this paper, we first calculate the realistic Earth matter effects on the detection of type II supernova neutrinos at the Daya Bay reactor neutrino experiment which is currently under construction. It is found that the Earth matter effects depend on the neutrino incident angle \\theta, the neutrino mass hierarchy \\Delta m_{31}^{2}, the crossing probability at the high resonance region inside the supernova, P_H, the neutrino temperature, T_{\\alpha}, and the pinching parameter in the neutrino spectrum, \\eta_{\\alpha}. We give the expression for the dependence of P_H on the neutrino mixing angle \\theta_{13}. With this we obtain the relations between \\theta_{13} and the event numbers for various reaction channels of supernova neutrinos. Using these relations, we propose a possible way to measure \\theta_{13} smaller than 1.5^\\circ. Such a sensitivity cannot be achieved by the Daya Bay neutrino experiment (the sensitivity of the ...

International Nuclear Information System (INIS)

Electricite de France, (EDF) in the late sixties and China through 10. 5-year Plan adopted the same approach of standardized NPPs to benefit from the series effect and to increase and speed up self reliance and localization. This approach also allows to continuously gather the feedback from design, construction and operation and to use it to constantly improve future and present nuclear power plants, by optimizing design features, construction phase and generation performances for safety, quality, cost and schedule aspects. Daya Bay NPP put into commercial operation in 1994 is posting high level safety and operation results. At Ling Ao NPP Chinese engineers of LANPC, with the contribution of the Chinese industry, have efficiency and successfully managed engineering, construction and operation preparation. GNPJVC / LANPC and EDF are developing permanent and mutual experience feedback exchanges in all areas of engineering, maintenance and operation. The results of ...

International Nuclear Information System (INIS)

The design boron concentration of the Boron Injection Tank (BIT) in Daya Bay Nuclear Power Station is 21000 #mu#g/g. The BIT should operate under high temperature to avoid boron crystallization, causing higher evaporation, frequent water makeup, higher deposition and pipe blockage to decrease the operability of the safety injection system. The author proposes to decrease the boron concentration in BIT from 21000 #mu#g/g to 7000 #mu#g/g to solve the existing problem. The safety analyses (core DNBR and containment response) are conducted and other impacts are evaluated for the BIT reduction. The analysis results show that the core DNBR meets the safety criterion and the containment pressure is within the design value for the steam line rupture accident after the BIT reduction. The feasibility study report of Daya bay BIT reduction has been approved by NNSA. The site implementation of BIT reduction has been finished successfully

International Nuclear Information System (INIS)

Daya Bay NPP has been operating safely and stably over 10 years since 1994, and its' seismic analysis of nuclear island was in accordance with the approaches in RCC-G standard for the model M310, in which the Simplified Impedance Matrix Method (SIMM) was employed for the consideration of SSI. Thanks to the rapid progress being made in upgrading the evaluation technology and the capability of data processing systems, methods and software tools for the SSI analysis have experienced significant development all over the world. Focused on the model of reactor building of the Daya Bay NPP, in his paper the more sophisticated 3D half-space continuum impedance method based on the Green functions is used to analyze the functions of the soil, and then the seismic responses of the coupled SSI system are calculated and compared with the corresponding design values. It demonstrates that the design method provides a set of conservatively safe results. The ...

International Nuclear Information System (INIS)

Compared with that of Daya Bay Nuclear Power Plant, the reactor power of QS-II Nuclear Power Plant is decreased and the primary coolant system is changed from three loops to two loops. Thereby the related systems were re-designed, and corresponding tests and engineering validation were carried out. Results of preliminary operation indicate that it is successful. The author describes the design modifications, features and corresponding tests of some systems, reflecting the successful incorporation of engineering and testing, and revealing the capability to develop nuclear power and design the large or medium sized commercial NPP on Self-Reliance in China

International Nuclear Information System (INIS)

Collection, analysis and quantification of human factor data are important compositions of human reliability analysis (HRA) and probabilistic risk assessment (PRA). Various human factor databases have been set up, but there are comparatively little human factor data management systems which can be uses for collection, classification, analysis, calculation and predication of the human factor data. Therefore, the human factor data management system for Daya Bay NPP is developed, with the following three modules and four databases: original data module, computing module, introduced data module, and basic database, other data source of the plant, external database and introduced database. The foundational problems about human factor data and the systemic structure and function are described. The data structure in the database is also discussed, because it is of the most importance in the system

British Library Electronic Table of Contents (United Kingdom)

Changes in cell density and cyst flux of Alexandrium tamarense, paralytic shellfish poisoning (PSP) toxin contents in shellfishes, and environmental parameters were measured in two stations in Daya Bay, South China Sea from March 2005 to July 2006. Vegetative cells of A. tamarense occurred sporadically; however, they presented abundantly during the winter months. Meanwhile, cyst flux reached its maximum level just following the peak abundance of motile cells. The PSP contents in shellfish were generally low, but higher in winter with the maximum of 14,015 @mg STX equiv./kg. The majority of toxins were found in digestive glands, with a maximum of 66,227 @mg STX equiv./kg. There were significant positive relationships between toxin level and vegetative cell density and cyst flux. This indica...

International Nuclear Information System (INIS)

The author applies the GO methodology to reliability analysis of the offsite power supply system of Daya Bay NPP. The direct quantitative calculation formulas of the stable reliability target of the system with shared signals and the dynamic calculation formulas of the state probability for the unit with two states are derived. The method to solve the fault event sets of the system is also presented and all the fault event sets of the outer power supply system and their failure probability are obtained. The resumption reliability of the offsite power supply system after the stability failure of the power net is also calculated. The result shows that the GO methodology is very simple and useful in the stable and dynamic reliability analysis of the repairable system

CERN Document Server

In this paper, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about $\\theta_{13}$ smaller than $1.5^\\circ$ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.

CERN Document Server

Several new reactor neutrino experiments are being considered to measure the parameter theta-13. The current plans for Angra, Braidwood, Daya Bay, KASKA and KR2DET are reviewed. A case is made that, together with Double-CHOOZ, a future world program should include at least three such experiments.

CERN Document Server

The "texture zero mass matrices" for the quarks and leptons describe very well the flavor mixing of the quarks and leptons. We can calculate the angles of the unitarity triangle. We expect the angle alpha of the unitarity triangle to be 90 degrees. The masses of the neutrinos can be calculated - they are very small, the largest neutrino mass is 0.05 eV. We calculated the matrix element of the mixing matrix, relevant for the reactor mixing angle. It can be measured in the near future in the DAYA BAY experiment.

British Library Electronic Table of Contents (United Kingdom)

Objectification theory contends that women are socialized to view their body as an object to be evaluated by others (Fredickson and Roberts 1997). In contrast, pregnancy may be a time that women are more attuned to their body?s functionality. Extending objectification theory, we investigate relationships among body surveillance, awareness and appreciation of body functionality, depressive symptoms, and prenatal health behaviors among an on-line sample of 156 predominantly White, middle-class pregnant women from throughout the U.S recruited through maternity stores, message boards, listservs, and snowballing techniques. We examine whether higher levels of awareness and appreciation of body functionality may attenuate, and thereby possibly protect women from the negative effects of high body...

Energy Technology Data Exchange (ETDEWEB)

We present sufficient conditions that imply duality for the algebras of local observables in all Abelian sectors of all locally normal, irreducible representations of a field algebra if twisted duality obtains in one of these representations. It is verified that the Yukawa/sub 2/ model satisfies these conditions, yielding the first proof of duality for the observable algebra in all coherent charge sectors in this model. This paper also constitutes the first verification of the assumptions of the axiomatic study of the structure of superselection sectors by Doplicher, Haag and Roberts in an interacting model with nontrivial sectors. The existence of normal product states for the free Fermi field algebra and, thus, the verification of the funnel property for the associated net of local algebras are demonstrated.

Science.gov (United States)

Since The Meaning of Evolution (1992), Robert J. Richards has argued that modern evolutionary theory is rooted in late 18th-century Romantic science. The publication of The Tragic Sense of Life (2009) provides a fitting occasion to evaluate how this perspective revises the standard history of biological thought. This essay focuses on three aspects of Richards's attempt to rehabilitate the reputation of German Naturphilosophie: (1) the identification of Romantic strains in Charles Darwin's portrait of evolutionary history; (2) the demonstration that any attempt to treat Ernst Haeckel as a "pseudo-Darwinian" inevitably renders Darwin himself a "pseudo-Darwinian"; and (3) the denial of Haeckel's alleged responsibility for the rise of Nazi racial hygiene. This article examines Richards's case for clearing Haeckel's name, as well as the subsequent (slanderous) charge from Daniel Gasman that Richards is guilty of whitewashing the Haeckelian roots of the Holocaust. ...

International Nuclear Information System (INIS)

Stretch-out operation mode can deepen the reactor burnup when the boron concentration is near 0 mg/L, in which the additional reactivity is introduced by the reducing of the moderator temperature and the decreasing of the load. Stretch-out is used in many nuclear power plants all over the world. The first stretch-out operation has been used for the first time in China. As a specific operation mode, which outruns the original reactor core design, the related and specialized design argument and safety analysis is required. As a consequence of the continuous or stepwise reduction of load and moderator temperature, the neurotic measurement system and the reactor control and protection system parameters should be modified specially. Based on the schedule of the electricity production, the first stretch-out operation had been carried out from March 12 to March 21 2003. It successfully avoided the overlapping between 209 and 109 inspection shutdowns in Daya Bay Nuclear ...

International Nuclear Information System (INIS)

With the practice of 10 years safe operation, Daya Bay Nuclear Power Station has established and continuously improved the management system for radiation protection and optimization (ALARA) which contains 3 basic requirements: all workers are trained, all employees are engaged in totally, and work management is implemented for the whole process. At the same time, strong efforts have been made to build the 'infrastructure' as a platform for its effective operation. This article introduces the contents and characteristics of the system and basic experiences of its effective implementation. In order to implement the management system effectively, it is necessary for NPPs to strengthen the responsibility system for radiation protection and the leading role of the radiation protection personnel, especially the role of technical support and supervision during the work with high radiation risk, emphasize the organic combination and actively mutual action with the safe ...

International Nuclear Information System (INIS)

In this paper, an investigation was performed on a failure pressure vessel, which was as an anti-freezing heater for General Gas Storage and Distribution (SGZ) system. Evident and serious deformation was observed on the body of the vessel. A metallurgical investigation was conducted to establish the mechanism and cause of deformation of the anti-freezing heater at Daya Bay PWR station in China. The investigation, which was performed on specimens cut from the most serious area deformed of the vessel, included macroscopic examination and microscopy examination. The results of the examinations showed that some lamellar pearlite in the microstructure were already spheroidized. It was confirmed that the vessel was operated at high temperature. Stress analysis for the vessel was conducted. And it was confirmed that, in ideal conditions, the vessel would be deformed at around 420 C. The overall results of the investigation showed that the failure of the protected ...

International Nuclear Information System (INIS)

Based on a detailed analysis of the inter-relationship in the current, voltage, electromagnetic torque and ratio of the difference between the speed of rotor and the speed of rotary magnetic field to the later in the motor, the root cause was point out, which leads to the protection fuses' failure of the motor in the starting stage, which drives the turbine-generator set to rotate at low speed before its startup. Two solutions to avoid the situation are proposed, too. (authors)

CERN Document Server

We study non-standard interactions (NSIs) at reactor neutrino experiments, and in particular, the mimicking effects on \\theta_13. We present generic formulas for oscillation probabilities including NSIs from sources and detectors. Instructive mappings between the fundamental leptonic mixing parameters and the effective leptonic mixing parameters are established. In addition, NSI corrections to the mixing angles \\theta_13 and \\theta_12 are discussed in detailed. Finally, we show that, even for a vanishing \\theta_13, an oscillation phenomenon may still be observed in future short baseline reactor neutrino experiments, such as Double Chooz and Daya Bay, due to the existences of NSIs.

International Nuclear Information System (INIS)

Based on the practical condition of the plant and in reference to advanced management experiences worldwide, Daya Bay Nuclear Power Plant has established its own peculiar management system for radiation protection management and ALARA implementation. The characteristics of the system are: radiation protection training to all workers, active involvement of all managers and staffs, and whole process safety control to maintenance activities. The management philosophy of 'workers are responsible for their own radiation safety' is adopted in the plant. A strict, formalized and systematic whole staff radiation protection training, evaluation, authorization and periodically refreshing mechanism had been established and executed in the plant. In the organizational point of view, the responsibilities of line managers were specified in plant procedures, ALARA coordination organization on plant level and for specific activities were established. Meanwhile, the plant ...

International Nuclear Information System (INIS)

Objective: To survey the data for the state of health in the ambient residents of Daya Bay Nuclear Power Plant, and provide the background data to evaluate the state of health affected by fallout of nuclear power plant. Methods: The datas were collected by a radiation epidemiology. The investigation was carried out in the area within 20 km of radius from Daya Bay Nuclear' Power Plant, and the subjects who had lived there for three years or longer before January. 1,1993 and covered by the Household Registry were recruited to a cohort. Results: The mortality rate of overall cancer (per 100 000 PYr) was 88.57 (the standard mortality rate was 79.77 ), the mortality rate of leukemia (per 100 000 PYr) was 3.24 (the standard mortality rate was 2.94), the palpation rate of the goiter in 7-14 years old was 8.34%(9.69% in B ultrasonic), the morbidity rate of newborn's defect (per 100 00 P) was 82.33. The mortality of all cancers or leukemia was similar ...

International Nuclear Information System (INIS)

The paper introduces the disposal procedures of the old reactor pressure vessel head. Reactor pressure vessel (RPV) heads were replaced successfully in Daya Bay Nuclear Power Plant. The on-site treatment and disposal of replaced heads was thereafter implemented. This is the first time in China for large size radioactive article disposal. To guarantee the safety of old head treatment, issues of radiation protection have to be taken into account. Dose rate distribution of the old head surface and radioactivity were initially calculated according to the operation history and the neutron flux rate of the reactor. Shielding calculation and package design was thereafter worked out based on the data obtained from the old head, e.g. neutron flux, sorts of nuclides, radioactivity and dose rates. Shielding package was afterwards manufactured in special factories and transported to Daya Bay NPP site by truck and ship. The shielding package was designed ...

International Nuclear Information System (INIS)

This paper reports on pumped storage plants which have become an effective way for some utility companies that derive power from hydroelectric facilities to economically store baseload energy during off-peak hours for use during peak hourly demands. According to the Electric Power Research Institute (EPRI) in Palo Alto, Calif., 36 of these plants provide approximately 20 gigawatts, or about 3 percent of U.S. generating capacity. During peak-demand periods, utilities are often stretched beyond their capacity to provide power and must therefore purchase it from neighboring utilities. Building new baseload power plants, typically nuclear or coal-fired facilities that run 24 hours per day seven days a week, is expensive, about $1500 per kilowatt, according to Robert Schainker, program manager for energy storage at the EPRI. Schainker the that building peaking plants at $400 per kilowatt, which run a few hours a day on gas or oil fuel, is less costly than building ...

Energy Technology Data Exchange (ETDEWEB)

Flow-curve characteristics of the heat-resistant steels X 20 CrMoV 12.1 and alloy 800 (X5NiCrTiAl32.20) were measured by tensile and compression tests at temperatures between room temperature and 800 C and strain rates {epsilon}{<=}10 s{sup -1} in connection with microstructure investigations (dislocation content, carbide precipitation) by TEM and X-ray diffraction analysis (XDA). Modelling the deformation behaviour of the steels in terms of the microstructure development indicates that it cannot be explained in a simple manner. The flow curves {sigma}={sigma}({epsilon}, {epsilon}, T) lie, in general, between those predicted by the Kocks-Mecking-Estrin model and a modified (i.e. two-parameter) Roberts model. Because of the less complicated nature of the deformation process the correspondence of experiment and modelling is more satisfying in the case of the material X 20 CrMoV 12.1. (orig.) 26 refs.

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT. The morphology, morphogenesis, and phylogeny of Diophrys parappendiculata n. sp., a large marine ciliate isolated from the coastal waters of Daya Bay, southern China, were investigated. This new species is characterized by a combination of its large size, appendiculata-pattern of ciliature, and bipartite adoral zone of membranelles. The main stages of morphogenesis during binary fission were also recorded and described. Comparisons of morphological characteristics with similar congeners support the validity of the new species. The small subunit rRNA gene sequence of D. parappendiculata is 96.3-99.94% similar to those of four other congeners; it differs in four nucleotides from that of Diophrys appendiculata (i.e. structural similarity was 99.94%). Phylogenetic analysis indicates ...

British Library Electronic Table of Contents (United Kingdom)

Samples of two seawater farmed fish (crimson snapper (Lutjanus erythopterus) and snubnose pompano (Trachinotus blochii)), water, air, sediment, fish feed, macroalgae and phytoplankton were collected from two estuarine bays (Daya Bay and Hailing Bay) in South China. The concentrations of persistent halogenated compounds (PHCs) including polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and polychlorinated biphenyls (PCBs) varied widely with the different sample matrices under investigation. The compositional patterns in fish, fish feed, macroalgae and phytoplankton, as well as the good correlations between the abundances of p,pprime-DDT and BDE-209 and their metabolites (i.e., p,pprime-DDD and p,pprime-DDE for p,pprime-DDT and BDE-47 for BDE-209) in fish indicated the occurr...

CERN Document Server

We discuss first the flavor mixing of the quarks, using the texture zero mass matrices. Then we study a similar model for the mass matrices of the leptons. We are able to relate the mass eigenvalues of the charged leptons and of the neutrinos to the mixing angles and can predict the masses of the neutrinos. We find a normal hierarchy - the masses are 0.004 eV, 0.01 eV and 0.05 eV. The atmospheric mixing angle is given by the mass ratios of the charged leptons and the neutrinos. we find about 40 degrees, consistent with the experiments. The mixing element, connecting the first neutrino wit the electron, is predicted to be 0.05. This prediction can soon be checked by the Daya Bay experiment.

Energy Technology Data Exchange (ETDEWEB)

This paper presents an overview of research conducted with the support of the Australian Institute of Nuclear Science and Engineering, at the University of Melbourne, School of Earth Sciences, Radiochemical Neutron Activation Laboratory. The primary objective of this research is to realize the high potential of the platinum group elements (PGE) and gold to the solution of petrogenetic problems, the study of magma generation and magmatic processes in mafic/ultramafic rock suites, as tracers in hydrothermal ore formation. The PGEs (Os, Ru, Ir, Pt, Pd and Rh) are among the least abundant of all elements on earth with unique properties such as high melting points, high electrical and thermal conductivity, high density, strength and toughness as alloys. They exhibit both siderophile and chalcophile characteristics and are valuable tools in providing information about magmatic processes, in particular S-saturation, as well as crystal fractionation trends. Two distinct groups of PGEs are ...

Energy Technology Data Exchange (ETDEWEB)

Waste management, like many other issues, has experienced major milestones. In 1971, the Calvert Cliff's decision resulted in an entirely different approach to the consideration of environmental impact analysis in reactor siting. The accidents at Three Mile Island and Chernobyl have had profound effects on nuclear power plant design. The high-level waste repository program has had many similar experiences that have modified the course of events. The management of radioactive, hazardous chemical and mixed waste in all of the facilities of the Oak Ridge Operations (ORO) Office of the Department of Energy (DOE) took on an entirely different meaning in 1984. On April 13, 1984, Federal Judge Robert Taylor said that DOE should proceed 'with all deliberate speed' to bring the Y-12 plant into compliance with the Resource Conservation and Recovery Act and the Clean Water Act. This decision resulted from a suit brought by the Legal Environmental ...

International Nuclear Information System (INIS)

For the recruitment, training and position qualification of the simulator instructors and feedback of training effect, the management approaches are formulated in 'The System for Simulator Training and Licensing Examination of Daya Bay Nuclear Power Station Operators'. The concrete requirements on the professional knowledge, work experience and foreign language ability of a simulator instructor are put forward. The process of instructor training is designed. The training items include the trainer training, pedagogy training, time management training, operation activities training during outage of unit, 'shadow' training and on-the-jot training on simulator courses. Job rotation is realized between simulator instructor and licensing personnel on site. New simulator instructor must pass the qualification identification. After a duration of 2 years, re-qualification has to be carried out. On the basis of the operator training method introduced from EDF (electricite De ...

CERN Document Server

We study the impact of very light sterile neutrinos (Delta m^2_new around 1 to 10 times 10^(-2) eV^2, sin^2 2theta_new<10^(-1)) on upcoming theta_13-driven reactor antineutrino experiments like Double-CHOOZ and Daya Bay. Oscillations driven by these vales of Delta m^2_new affect data in the near and far detectors differently and hence potentially modify the capability of these experimental setups to constrain and measure sin^2 2theta_13. We find that the hypothesis theta_new different from zero negatively impacts one's ability to either place an upper bound on sin^2 2theta_13 in the advent of no oscillation signal or measure sin^2 2theta_13 if a theta_13-driven signal is observed. The impact of sterile neutrino effects, however, depends significantly on one's ability to measure the recoil positron energy spectrum. If sin^2 2theta_new is larger than 10^(-2), upcoming theta_13-driven reactor antineutrino experiments should be able to measure sin^2 2theta_new and ...

CERN Document Server

Very soon a new generation of reactor and accelerator neutrino oscillation experiments - Double Chooz, Daya Bay, Reno and T2K - will seek for oscillation signals generated by the mixing parameter theta_13. The knowledge of this angle is a fundamental milestone to optimize further experiments aimed at detecting CP violation in the neutrino sector. Leptonic CP violation is a key phenomenon that has profound implications in particle physics and cosmology but it is clearly out of reach for the aforementioned experiments. Since late 90's, a world-wide activity is in progress to design facilities that can access CP violation in neutrino oscillation and perform high precision measurements of the lepton counterpart of the Cabibbo-Kobayashi-Maskawa matrix. In this paper the status of these studies will be summarized, focusing on the options that are best suited to exploit existing European facilities (firstly CERN and the INFN Gran Sasso Laboratories) or technologies where ...

British Library Electronic Table of Contents (United Kingdom)

Concentrations of trace metals were determined in water, sediment, fish feed and two species of farmed fish, pompano and snapper, collected from Daya Bay and Hailing Bay of South China in July 2007 and January 2008. Total average concentrations of Cu, Pb, Zn, Cd, Cr, Hg and As were 1.6, 2.7, 27.3, 0.025, 0.62, 0.18 and 0.59?g/gdrywt in pompano and 1.5, 2.6, 23.6, 0.020, 0.55, 0.22 and 0.53?g/gdrywt in snapper. In general, the concentrations of all target metals except Hg were positively correlated with lipid contents whereas negative correlations were observed between the metal concentrations and fish body weights. Model calculation indicated that dietary uptake of Zn and Cd predominate their accumulation in snapper, accounting for 99.9% and 98.2% of the total inputs. Risk ...

International Nuclear Information System (INIS)

During the last ten years, the U.S. Nuclear Regulatory Commission and the U.S. nuclear utilities have been developing methods and requirements for risk-informed applications making use of probabilistic risk assessments (PRA) of nuclear power plants. Early in this process, it became clear that the existing PRAs were done with different objectives and methodologies by different analysts. For uniformity and consistency in future risk-informed applications, industry consensus standards on probabilistic risk assessments were deemed to be essential. Currently, the following standards have been published or under preparation: - ASME RA-S-2002: 'Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications', Addendum C, March 2005. - ANSI/ANS-58.21-2003 'External-Events PRA Methodology' March 2003. - ANS-58.22 'Low Power and Shutdown PRA Standard'. - ANS-58.23 'Fire PRA Methodology Standard'. - ANS Level 2 and Level 3 PRA Standards. The ASME Standard specifies the ...

International Nuclear Information System (INIS)

Development and deployment of small-scale nuclear power reactors and their maintenance, monitoring, and control are part of the mission under the Small Modular Reactor (SMR) program. The objectives of this NERI-consortium research project are to investigate, develop, and validate advanced methods for sensing, controlling, monitoring, diagnosis, and prognosis of these reactors, and to demonstrate the methods with application to one of the proposed integral pressurized water reactors (IPWR). For this project, the IPWR design by Westinghouse, the International Reactor Secure and Innovative (IRIS), has been used to demonstrate the techniques developed under this project. The research focuses on three topical areas with the following objectives. Objective 1 - Develop and apply simulation capabilities and sensitivity/uncertainty analysis methods to address sensor deployment analysis and small grid stability issues. Objective 2 - Develop and test an autonomous and fault-tolerant control ...